/* Needed for the definition of va_list */
+
+/*
+** Make sure we can call this stuff from C++.
+*/
+#if 0
+extern "C" {
+#endif
+
+
+/*
+** Add the ability to override 'extern'
+*/
+#ifndef SQLITE_EXTERN
+# define SQLITE_EXTERN extern
+#endif
+
+#ifndef SQLITE_API
+# define SQLITE_API
+#endif
+
+
+/*
+** These no-op macros are used in front of interfaces to mark those
+** interfaces as either deprecated or experimental. New applications
+** should not use deprecated interfaces - they are support for backwards
+** compatibility only. Application writers should be aware that
+** experimental interfaces are subject to change in point releases.
+**
+** These macros used to resolve to various kinds of compiler magic that
+** would generate warning messages when they were used. But that
+** compiler magic ended up generating such a flurry of bug reports
+** that we have taken it all out and gone back to using simple
+** noop macros.
+*/
+#define SQLITE_DEPRECATED
+#define SQLITE_EXPERIMENTAL
+
+/*
+** Ensure these symbols were not defined by some previous header file.
+*/
+#ifdef SQLITE_VERSION
+# undef SQLITE_VERSION
+#endif
+#ifdef SQLITE_VERSION_NUMBER
+# undef SQLITE_VERSION_NUMBER
+#endif
+
+/*
+** CAPI3REF: Compile-Time Library Version Numbers
+**
+** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
+** evaluates to a string literal that is the SQLite version in the
+** format "X.Y.Z" where X is the major version number (always 3 for
+** SQLite3) and Y is the minor version number and Z is the release number.)^
+** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
+** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
+** numbers used in [SQLITE_VERSION].)^
+** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
+** be larger than the release from which it is derived. Either Y will
+** be held constant and Z will be incremented or else Y will be incremented
+** and Z will be reset to zero.
+**
+** Since version 3.6.18, SQLite source code has been stored in the
+** Fossil configuration management
+** system. ^The SQLITE_SOURCE_ID macro evaluates to
+** a string which identifies a particular check-in of SQLite
+** within its configuration management system. ^The SQLITE_SOURCE_ID
+** string contains the date and time of the check-in (UTC) and an SHA1
+** hash of the entire source tree.
+**
+** See also: [sqlite3_libversion()],
+** [sqlite3_libversion_number()], [sqlite3_sourceid()],
+** [sqlite_version()] and [sqlite_source_id()].
+*/
+#define SQLITE_VERSION "3.8.5"
+#define SQLITE_VERSION_NUMBER 3008005
+#define SQLITE_SOURCE_ID "2014-06-04 14:06:34 b1ed4f2a34ba66c29b130f8d13e9092758019212"
+
+/*
+** CAPI3REF: Run-Time Library Version Numbers
+** KEYWORDS: sqlite3_version, sqlite3_sourceid
+**
+** These interfaces provide the same information as the [SQLITE_VERSION],
+** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
+** but are associated with the library instead of the header file. ^(Cautious
+** programmers might include assert() statements in their application to
+** verify that values returned by these interfaces match the macros in
+** the header, and thus insure that the application is
+** compiled with matching library and header files.
+**
+**
+** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
+** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
+** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
+**
)^
+**
+** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
+** macro. ^The sqlite3_libversion() function returns a pointer to the
+** to the sqlite3_version[] string constant. The sqlite3_libversion()
+** function is provided for use in DLLs since DLL users usually do not have
+** direct access to string constants within the DLL. ^The
+** sqlite3_libversion_number() function returns an integer equal to
+** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
+** a pointer to a string constant whose value is the same as the
+** [SQLITE_SOURCE_ID] C preprocessor macro.
+**
+** See also: [sqlite_version()] and [sqlite_source_id()].
+*/
+SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
+SQLITE_API const char *sqlite3_libversion(void);
+SQLITE_API const char *sqlite3_sourceid(void);
+SQLITE_API int sqlite3_libversion_number(void);
+
+/*
+** CAPI3REF: Run-Time Library Compilation Options Diagnostics
+**
+** ^The sqlite3_compileoption_used() function returns 0 or 1
+** indicating whether the specified option was defined at
+** compile time. ^The SQLITE_ prefix may be omitted from the
+** option name passed to sqlite3_compileoption_used().
+**
+** ^The sqlite3_compileoption_get() function allows iterating
+** over the list of options that were defined at compile time by
+** returning the N-th compile time option string. ^If N is out of range,
+** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
+** prefix is omitted from any strings returned by
+** sqlite3_compileoption_get().
+**
+** ^Support for the diagnostic functions sqlite3_compileoption_used()
+** and sqlite3_compileoption_get() may be omitted by specifying the
+** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
+**
+** See also: SQL functions [sqlite_compileoption_used()] and
+** [sqlite_compileoption_get()] and the [compile_options pragma].
+*/
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
+SQLITE_API const char *sqlite3_compileoption_get(int N);
+#endif
+
+/*
+** CAPI3REF: Test To See If The Library Is Threadsafe
+**
+** ^The sqlite3_threadsafe() function returns zero if and only if
+** SQLite was compiled with mutexing code omitted due to the
+** [SQLITE_THREADSAFE] compile-time option being set to 0.
+**
+** SQLite can be compiled with or without mutexes. When
+** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
+** are enabled and SQLite is threadsafe. When the
+** [SQLITE_THREADSAFE] macro is 0,
+** the mutexes are omitted. Without the mutexes, it is not safe
+** to use SQLite concurrently from more than one thread.
+**
+** Enabling mutexes incurs a measurable performance penalty.
+** So if speed is of utmost importance, it makes sense to disable
+** the mutexes. But for maximum safety, mutexes should be enabled.
+** ^The default behavior is for mutexes to be enabled.
+**
+** This interface can be used by an application to make sure that the
+** version of SQLite that it is linking against was compiled with
+** the desired setting of the [SQLITE_THREADSAFE] macro.
+**
+** This interface only reports on the compile-time mutex setting
+** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
+** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
+** can be fully or partially disabled using a call to [sqlite3_config()]
+** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
+** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
+** sqlite3_threadsafe() function shows only the compile-time setting of
+** thread safety, not any run-time changes to that setting made by
+** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
+** is unchanged by calls to sqlite3_config().)^
+**
+** See the [threading mode] documentation for additional information.
+*/
+SQLITE_API int sqlite3_threadsafe(void);
+
+/*
+** CAPI3REF: Database Connection Handle
+** KEYWORDS: {database connection} {database connections}
+**
+** Each open SQLite database is represented by a pointer to an instance of
+** the opaque structure named "sqlite3". It is useful to think of an sqlite3
+** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
+** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
+** and [sqlite3_close_v2()] are its destructors. There are many other
+** interfaces (such as
+** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
+** [sqlite3_busy_timeout()] to name but three) that are methods on an
+** sqlite3 object.
+*/
+typedef struct sqlite3 sqlite3;
+
+/*
+** CAPI3REF: 64-Bit Integer Types
+** KEYWORDS: sqlite_int64 sqlite_uint64
+**
+** Because there is no cross-platform way to specify 64-bit integer types
+** SQLite includes typedefs for 64-bit signed and unsigned integers.
+**
+** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
+** The sqlite_int64 and sqlite_uint64 types are supported for backwards
+** compatibility only.
+**
+** ^The sqlite3_int64 and sqlite_int64 types can store integer values
+** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
+** sqlite3_uint64 and sqlite_uint64 types can store integer values
+** between 0 and +18446744073709551615 inclusive.
+*/
+#ifdef SQLITE_INT64_TYPE
+ typedef SQLITE_INT64_TYPE sqlite_int64;
+ typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
+#elif defined(_MSC_VER) || defined(__BORLANDC__)
+ typedef __int64 sqlite_int64;
+ typedef unsigned __int64 sqlite_uint64;
+#else
+ typedef long long int sqlite_int64;
+ typedef unsigned long long int sqlite_uint64;
+#endif
+typedef sqlite_int64 sqlite3_int64;
+typedef sqlite_uint64 sqlite3_uint64;
+
+/*
+** If compiling for a processor that lacks floating point support,
+** substitute integer for floating-point.
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define double sqlite3_int64
+#endif
+
+/*
+** CAPI3REF: Closing A Database Connection
+**
+** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
+** for the [sqlite3] object.
+** ^Calls to sqlite3_close() and sqlite3_close_v2() return SQLITE_OK if
+** the [sqlite3] object is successfully destroyed and all associated
+** resources are deallocated.
+**
+** ^If the database connection is associated with unfinalized prepared
+** statements or unfinished sqlite3_backup objects then sqlite3_close()
+** will leave the database connection open and return [SQLITE_BUSY].
+** ^If sqlite3_close_v2() is called with unfinalized prepared statements
+** and unfinished sqlite3_backups, then the database connection becomes
+** an unusable "zombie" which will automatically be deallocated when the
+** last prepared statement is finalized or the last sqlite3_backup is
+** finished. The sqlite3_close_v2() interface is intended for use with
+** host languages that are garbage collected, and where the order in which
+** destructors are called is arbitrary.
+**
+** Applications should [sqlite3_finalize | finalize] all [prepared statements],
+** [sqlite3_blob_close | close] all [BLOB handles], and
+** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
+** with the [sqlite3] object prior to attempting to close the object. ^If
+** sqlite3_close_v2() is called on a [database connection] that still has
+** outstanding [prepared statements], [BLOB handles], and/or
+** [sqlite3_backup] objects then it returns SQLITE_OK but the deallocation
+** of resources is deferred until all [prepared statements], [BLOB handles],
+** and [sqlite3_backup] objects are also destroyed.
+**
+** ^If an [sqlite3] object is destroyed while a transaction is open,
+** the transaction is automatically rolled back.
+**
+** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
+** must be either a NULL
+** pointer or an [sqlite3] object pointer obtained
+** from [sqlite3_open()], [sqlite3_open16()], or
+** [sqlite3_open_v2()], and not previously closed.
+** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
+** argument is a harmless no-op.
+*/
+SQLITE_API int sqlite3_close(sqlite3*);
+SQLITE_API int sqlite3_close_v2(sqlite3*);
+
+/*
+** The type for a callback function.
+** This is legacy and deprecated. It is included for historical
+** compatibility and is not documented.
+*/
+typedef int (*sqlite3_callback)(void*,int,char**, char**);
+
+/*
+** CAPI3REF: One-Step Query Execution Interface
+**
+** The sqlite3_exec() interface is a convenience wrapper around
+** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
+** that allows an application to run multiple statements of SQL
+** without having to use a lot of C code.
+**
+** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
+** semicolon-separate SQL statements passed into its 2nd argument,
+** in the context of the [database connection] passed in as its 1st
+** argument. ^If the callback function of the 3rd argument to
+** sqlite3_exec() is not NULL, then it is invoked for each result row
+** coming out of the evaluated SQL statements. ^The 4th argument to
+** sqlite3_exec() is relayed through to the 1st argument of each
+** callback invocation. ^If the callback pointer to sqlite3_exec()
+** is NULL, then no callback is ever invoked and result rows are
+** ignored.
+**
+** ^If an error occurs while evaluating the SQL statements passed into
+** sqlite3_exec(), then execution of the current statement stops and
+** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
+** is not NULL then any error message is written into memory obtained
+** from [sqlite3_malloc()] and passed back through the 5th parameter.
+** To avoid memory leaks, the application should invoke [sqlite3_free()]
+** on error message strings returned through the 5th parameter of
+** of sqlite3_exec() after the error message string is no longer needed.
+** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
+** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
+** NULL before returning.
+**
+** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
+** routine returns SQLITE_ABORT without invoking the callback again and
+** without running any subsequent SQL statements.
+**
+** ^The 2nd argument to the sqlite3_exec() callback function is the
+** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
+** callback is an array of pointers to strings obtained as if from
+** [sqlite3_column_text()], one for each column. ^If an element of a
+** result row is NULL then the corresponding string pointer for the
+** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
+** sqlite3_exec() callback is an array of pointers to strings where each
+** entry represents the name of corresponding result column as obtained
+** from [sqlite3_column_name()].
+**
+** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
+** to an empty string, or a pointer that contains only whitespace and/or
+** SQL comments, then no SQL statements are evaluated and the database
+** is not changed.
+**
+** Restrictions:
+**
+**
+** - The application must insure that the 1st parameter to sqlite3_exec()
+** is a valid and open [database connection].
+**
- The application must not close the [database connection] specified by
+** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
+**
- The application must not modify the SQL statement text passed into
+** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
+**
+*/
+SQLITE_API int sqlite3_exec(
+ sqlite3*, /* An open database */
+ const char *sql, /* SQL to be evaluated */
+ int (*callback)(void*,int,char**,char**), /* Callback function */
+ void *, /* 1st argument to callback */
+ char **errmsg /* Error msg written here */
+);
+
+/*
+** CAPI3REF: Result Codes
+** KEYWORDS: SQLITE_OK {error code} {error codes}
+** KEYWORDS: {result code} {result codes}
+**
+** Many SQLite functions return an integer result code from the set shown
+** here in order to indicate success or failure.
+**
+** New error codes may be added in future versions of SQLite.
+**
+** See also: [SQLITE_IOERR_READ | extended result codes],
+** [sqlite3_vtab_on_conflict()] [SQLITE_ROLLBACK | result codes].
+*/
+#define SQLITE_OK 0 /* Successful result */
+/* beginning-of-error-codes */
+#define SQLITE_ERROR 1 /* SQL error or missing database */
+#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
+#define SQLITE_PERM 3 /* Access permission denied */
+#define SQLITE_ABORT 4 /* Callback routine requested an abort */
+#define SQLITE_BUSY 5 /* The database file is locked */
+#define SQLITE_LOCKED 6 /* A table in the database is locked */
+#define SQLITE_NOMEM 7 /* A malloc() failed */
+#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
+#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
+#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
+#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
+#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
+#define SQLITE_FULL 13 /* Insertion failed because database is full */
+#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
+#define SQLITE_PROTOCOL 15 /* Database lock protocol error */
+#define SQLITE_EMPTY 16 /* Database is empty */
+#define SQLITE_SCHEMA 17 /* The database schema changed */
+#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
+#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
+#define SQLITE_MISMATCH 20 /* Data type mismatch */
+#define SQLITE_MISUSE 21 /* Library used incorrectly */
+#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
+#define SQLITE_AUTH 23 /* Authorization denied */
+#define SQLITE_FORMAT 24 /* Auxiliary database format error */
+#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
+#define SQLITE_NOTADB 26 /* File opened that is not a database file */
+#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
+#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
+#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
+#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
+/* end-of-error-codes */
+
+/*
+** CAPI3REF: Extended Result Codes
+** KEYWORDS: {extended error code} {extended error codes}
+** KEYWORDS: {extended result code} {extended result codes}
+**
+** In its default configuration, SQLite API routines return one of 26 integer
+** [SQLITE_OK | result codes]. However, experience has shown that many of
+** these result codes are too coarse-grained. They do not provide as
+** much information about problems as programmers might like. In an effort to
+** address this, newer versions of SQLite (version 3.3.8 and later) include
+** support for additional result codes that provide more detailed information
+** about errors. The extended result codes are enabled or disabled
+** on a per database connection basis using the
+** [sqlite3_extended_result_codes()] API.
+**
+** Some of the available extended result codes are listed here.
+** One may expect the number of extended result codes will increase
+** over time. Software that uses extended result codes should expect
+** to see new result codes in future releases of SQLite.
+**
+** The SQLITE_OK result code will never be extended. It will always
+** be exactly zero.
+*/
+#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
+#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
+#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
+#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
+#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
+#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
+#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
+#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
+#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
+#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
+#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
+#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
+#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
+#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
+#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
+#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
+#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
+#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
+#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
+#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
+#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
+#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
+#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
+#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
+#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
+#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
+#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
+#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
+#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
+#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
+#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
+#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
+#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
+#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
+#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
+#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
+#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
+#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
+#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
+#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
+#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
+#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
+#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
+#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
+#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
+#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
+#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
+#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
+#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
+#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
+#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
+#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
+
+/*
+** CAPI3REF: Flags For File Open Operations
+**
+** These bit values are intended for use in the
+** 3rd parameter to the [sqlite3_open_v2()] interface and
+** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
+*/
+#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
+#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
+#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
+#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
+#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
+#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
+#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
+#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
+#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
+#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
+#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
+
+/* Reserved: 0x00F00000 */
+
+/*
+** CAPI3REF: Device Characteristics
+**
+** The xDeviceCharacteristics method of the [sqlite3_io_methods]
+** object returns an integer which is a vector of these
+** bit values expressing I/O characteristics of the mass storage
+** device that holds the file that the [sqlite3_io_methods]
+** refers to.
+**
+** The SQLITE_IOCAP_ATOMIC property means that all writes of
+** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
+** mean that writes of blocks that are nnn bytes in size and
+** are aligned to an address which is an integer multiple of
+** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
+** that when data is appended to a file, the data is appended
+** first then the size of the file is extended, never the other
+** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
+** information is written to disk in the same order as calls
+** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
+** after reboot following a crash or power loss, the only bytes in a
+** file that were written at the application level might have changed
+** and that adjacent bytes, even bytes within the same sector are
+** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
+** flag indicate that a file cannot be deleted when open. The
+** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
+** read-only media and cannot be changed even by processes with
+** elevated privileges.
+*/
+#define SQLITE_IOCAP_ATOMIC 0x00000001
+#define SQLITE_IOCAP_ATOMIC512 0x00000002
+#define SQLITE_IOCAP_ATOMIC1K 0x00000004
+#define SQLITE_IOCAP_ATOMIC2K 0x00000008
+#define SQLITE_IOCAP_ATOMIC4K 0x00000010
+#define SQLITE_IOCAP_ATOMIC8K 0x00000020
+#define SQLITE_IOCAP_ATOMIC16K 0x00000040
+#define SQLITE_IOCAP_ATOMIC32K 0x00000080
+#define SQLITE_IOCAP_ATOMIC64K 0x00000100
+#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
+#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
+#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
+#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
+#define SQLITE_IOCAP_IMMUTABLE 0x00002000
+
+/*
+** CAPI3REF: File Locking Levels
+**
+** SQLite uses one of these integer values as the second
+** argument to calls it makes to the xLock() and xUnlock() methods
+** of an [sqlite3_io_methods] object.
+*/
+#define SQLITE_LOCK_NONE 0
+#define SQLITE_LOCK_SHARED 1
+#define SQLITE_LOCK_RESERVED 2
+#define SQLITE_LOCK_PENDING 3
+#define SQLITE_LOCK_EXCLUSIVE 4
+
+/*
+** CAPI3REF: Synchronization Type Flags
+**
+** When SQLite invokes the xSync() method of an
+** [sqlite3_io_methods] object it uses a combination of
+** these integer values as the second argument.
+**
+** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
+** sync operation only needs to flush data to mass storage. Inode
+** information need not be flushed. If the lower four bits of the flag
+** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
+** If the lower four bits equal SQLITE_SYNC_FULL, that means
+** to use Mac OS X style fullsync instead of fsync().
+**
+** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
+** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
+** settings. The [synchronous pragma] determines when calls to the
+** xSync VFS method occur and applies uniformly across all platforms.
+** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
+** energetic or rigorous or forceful the sync operations are and
+** only make a difference on Mac OSX for the default SQLite code.
+** (Third-party VFS implementations might also make the distinction
+** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
+** operating systems natively supported by SQLite, only Mac OSX
+** cares about the difference.)
+*/
+#define SQLITE_SYNC_NORMAL 0x00002
+#define SQLITE_SYNC_FULL 0x00003
+#define SQLITE_SYNC_DATAONLY 0x00010
+
+/*
+** CAPI3REF: OS Interface Open File Handle
+**
+** An [sqlite3_file] object represents an open file in the
+** [sqlite3_vfs | OS interface layer]. Individual OS interface
+** implementations will
+** want to subclass this object by appending additional fields
+** for their own use. The pMethods entry is a pointer to an
+** [sqlite3_io_methods] object that defines methods for performing
+** I/O operations on the open file.
+*/
+typedef struct sqlite3_file sqlite3_file;
+struct sqlite3_file {
+ const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
+};
+
+/*
+** CAPI3REF: OS Interface File Virtual Methods Object
+**
+** Every file opened by the [sqlite3_vfs.xOpen] method populates an
+** [sqlite3_file] object (or, more commonly, a subclass of the
+** [sqlite3_file] object) with a pointer to an instance of this object.
+** This object defines the methods used to perform various operations
+** against the open file represented by the [sqlite3_file] object.
+**
+** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
+** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
+** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
+** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
+** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
+** to NULL.
+**
+** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
+** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
+** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
+** flag may be ORed in to indicate that only the data of the file
+** and not its inode needs to be synced.
+**
+** The integer values to xLock() and xUnlock() are one of
+**
+** - [SQLITE_LOCK_NONE],
+**
- [SQLITE_LOCK_SHARED],
+**
- [SQLITE_LOCK_RESERVED],
+**
- [SQLITE_LOCK_PENDING], or
+**
- [SQLITE_LOCK_EXCLUSIVE].
+**
+** xLock() increases the lock. xUnlock() decreases the lock.
+** The xCheckReservedLock() method checks whether any database connection,
+** either in this process or in some other process, is holding a RESERVED,
+** PENDING, or EXCLUSIVE lock on the file. It returns true
+** if such a lock exists and false otherwise.
+**
+** The xFileControl() method is a generic interface that allows custom
+** VFS implementations to directly control an open file using the
+** [sqlite3_file_control()] interface. The second "op" argument is an
+** integer opcode. The third argument is a generic pointer intended to
+** point to a structure that may contain arguments or space in which to
+** write return values. Potential uses for xFileControl() might be
+** functions to enable blocking locks with timeouts, to change the
+** locking strategy (for example to use dot-file locks), to inquire
+** about the status of a lock, or to break stale locks. The SQLite
+** core reserves all opcodes less than 100 for its own use.
+** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
+** Applications that define a custom xFileControl method should use opcodes
+** greater than 100 to avoid conflicts. VFS implementations should
+** return [SQLITE_NOTFOUND] for file control opcodes that they do not
+** recognize.
+**
+** The xSectorSize() method returns the sector size of the
+** device that underlies the file. The sector size is the
+** minimum write that can be performed without disturbing
+** other bytes in the file. The xDeviceCharacteristics()
+** method returns a bit vector describing behaviors of the
+** underlying device:
+**
+**
+** - [SQLITE_IOCAP_ATOMIC]
+**
- [SQLITE_IOCAP_ATOMIC512]
+**
- [SQLITE_IOCAP_ATOMIC1K]
+**
- [SQLITE_IOCAP_ATOMIC2K]
+**
- [SQLITE_IOCAP_ATOMIC4K]
+**
- [SQLITE_IOCAP_ATOMIC8K]
+**
- [SQLITE_IOCAP_ATOMIC16K]
+**
- [SQLITE_IOCAP_ATOMIC32K]
+**
- [SQLITE_IOCAP_ATOMIC64K]
+**
- [SQLITE_IOCAP_SAFE_APPEND]
+**
- [SQLITE_IOCAP_SEQUENTIAL]
+**
+**
+** The SQLITE_IOCAP_ATOMIC property means that all writes of
+** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
+** mean that writes of blocks that are nnn bytes in size and
+** are aligned to an address which is an integer multiple of
+** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
+** that when data is appended to a file, the data is appended
+** first then the size of the file is extended, never the other
+** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
+** information is written to disk in the same order as calls
+** to xWrite().
+**
+** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
+** in the unread portions of the buffer with zeros. A VFS that
+** fails to zero-fill short reads might seem to work. However,
+** failure to zero-fill short reads will eventually lead to
+** database corruption.
+*/
+typedef struct sqlite3_io_methods sqlite3_io_methods;
+struct sqlite3_io_methods {
+ int iVersion;
+ int (*xClose)(sqlite3_file*);
+ int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
+ int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
+ int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
+ int (*xSync)(sqlite3_file*, int flags);
+ int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
+ int (*xLock)(sqlite3_file*, int);
+ int (*xUnlock)(sqlite3_file*, int);
+ int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
+ int (*xFileControl)(sqlite3_file*, int op, void *pArg);
+ int (*xSectorSize)(sqlite3_file*);
+ int (*xDeviceCharacteristics)(sqlite3_file*);
+ /* Methods above are valid for version 1 */
+ int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
+ int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
+ void (*xShmBarrier)(sqlite3_file*);
+ int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
+ /* Methods above are valid for version 2 */
+ int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
+ int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
+ /* Methods above are valid for version 3 */
+ /* Additional methods may be added in future releases */
+};
+
+/*
+** CAPI3REF: Standard File Control Opcodes
+**
+** These integer constants are opcodes for the xFileControl method
+** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
+** interface.
+**
+** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
+** opcode causes the xFileControl method to write the current state of
+** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
+** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
+** into an integer that the pArg argument points to. This capability
+** is used during testing and only needs to be supported when SQLITE_TEST
+** is defined.
+**
+** - [[SQLITE_FCNTL_SIZE_HINT]]
+** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
+** layer a hint of how large the database file will grow to be during the
+** current transaction. This hint is not guaranteed to be accurate but it
+** is often close. The underlying VFS might choose to preallocate database
+** file space based on this hint in order to help writes to the database
+** file run faster.
+**
+**
- [[SQLITE_FCNTL_CHUNK_SIZE]]
+** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
+** extends and truncates the database file in chunks of a size specified
+** by the user. The fourth argument to [sqlite3_file_control()] should
+** point to an integer (type int) containing the new chunk-size to use
+** for the nominated database. Allocating database file space in large
+** chunks (say 1MB at a time), may reduce file-system fragmentation and
+** improve performance on some systems.
+**
+**
- [[SQLITE_FCNTL_FILE_POINTER]]
+** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
+** to the [sqlite3_file] object associated with a particular database
+** connection. See the [sqlite3_file_control()] documentation for
+** additional information.
+**
+**
- [[SQLITE_FCNTL_SYNC_OMITTED]]
+** No longer in use.
+**
+**
- [[SQLITE_FCNTL_SYNC]]
+** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
+** sent to the VFS immediately before the xSync method is invoked on a
+** database file descriptor. Or, if the xSync method is not invoked
+** because the user has configured SQLite with
+** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
+** of the xSync method. In most cases, the pointer argument passed with
+** this file-control is NULL. However, if the database file is being synced
+** as part of a multi-database commit, the argument points to a nul-terminated
+** string containing the transactions master-journal file name. VFSes that
+** do not need this signal should silently ignore this opcode. Applications
+** should not call [sqlite3_file_control()] with this opcode as doing so may
+** disrupt the operation of the specialized VFSes that do require it.
+**
+**
- [[SQLITE_FCNTL_COMMIT_PHASETWO]]
+** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
+** and sent to the VFS after a transaction has been committed immediately
+** but before the database is unlocked. VFSes that do not need this signal
+** should silently ignore this opcode. Applications should not call
+** [sqlite3_file_control()] with this opcode as doing so may disrupt the
+** operation of the specialized VFSes that do require it.
+**
+**
- [[SQLITE_FCNTL_WIN32_AV_RETRY]]
+** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
+** retry counts and intervals for certain disk I/O operations for the
+** windows [VFS] in order to provide robustness in the presence of
+** anti-virus programs. By default, the windows VFS will retry file read,
+** file write, and file delete operations up to 10 times, with a delay
+** of 25 milliseconds before the first retry and with the delay increasing
+** by an additional 25 milliseconds with each subsequent retry. This
+** opcode allows these two values (10 retries and 25 milliseconds of delay)
+** to be adjusted. The values are changed for all database connections
+** within the same process. The argument is a pointer to an array of two
+** integers where the first integer i the new retry count and the second
+** integer is the delay. If either integer is negative, then the setting
+** is not changed but instead the prior value of that setting is written
+** into the array entry, allowing the current retry settings to be
+** interrogated. The zDbName parameter is ignored.
+**
+**
- [[SQLITE_FCNTL_PERSIST_WAL]]
+** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
+** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
+** write ahead log and shared memory files used for transaction control
+** are automatically deleted when the latest connection to the database
+** closes. Setting persistent WAL mode causes those files to persist after
+** close. Persisting the files is useful when other processes that do not
+** have write permission on the directory containing the database file want
+** to read the database file, as the WAL and shared memory files must exist
+** in order for the database to be readable. The fourth parameter to
+** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
+** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
+** WAL mode. If the integer is -1, then it is overwritten with the current
+** WAL persistence setting.
+**
+**
- [[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
+** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
+** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
+** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
+** xDeviceCharacteristics methods. The fourth parameter to
+** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
+** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
+** mode. If the integer is -1, then it is overwritten with the current
+** zero-damage mode setting.
+**
+**
- [[SQLITE_FCNTL_OVERWRITE]]
+** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
+** a write transaction to indicate that, unless it is rolled back for some
+** reason, the entire database file will be overwritten by the current
+** transaction. This is used by VACUUM operations.
+**
+**
- [[SQLITE_FCNTL_VFSNAME]]
+** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
+** all [VFSes] in the VFS stack. The names are of all VFS shims and the
+** final bottom-level VFS are written into memory obtained from
+** [sqlite3_malloc()] and the result is stored in the char* variable
+** that the fourth parameter of [sqlite3_file_control()] points to.
+** The caller is responsible for freeing the memory when done. As with
+** all file-control actions, there is no guarantee that this will actually
+** do anything. Callers should initialize the char* variable to a NULL
+** pointer in case this file-control is not implemented. This file-control
+** is intended for diagnostic use only.
+**
+**
- [[SQLITE_FCNTL_PRAGMA]]
+** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
+** file control is sent to the open [sqlite3_file] object corresponding
+** to the database file to which the pragma statement refers. ^The argument
+** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
+** pointers to strings (char**) in which the second element of the array
+** is the name of the pragma and the third element is the argument to the
+** pragma or NULL if the pragma has no argument. ^The handler for an
+** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
+** of the char** argument point to a string obtained from [sqlite3_mprintf()]
+** or the equivalent and that string will become the result of the pragma or
+** the error message if the pragma fails. ^If the
+** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
+** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
+** file control returns [SQLITE_OK], then the parser assumes that the
+** VFS has handled the PRAGMA itself and the parser generates a no-op
+** prepared statement. ^If the [SQLITE_FCNTL_PRAGMA] file control returns
+** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
+** that the VFS encountered an error while handling the [PRAGMA] and the
+** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
+** file control occurs at the beginning of pragma statement analysis and so
+** it is able to override built-in [PRAGMA] statements.
+**
+**
- [[SQLITE_FCNTL_BUSYHANDLER]]
+** ^The [SQLITE_FCNTL_BUSYHANDLER]
+** file-control may be invoked by SQLite on the database file handle
+** shortly after it is opened in order to provide a custom VFS with access
+** to the connections busy-handler callback. The argument is of type (void **)
+** - an array of two (void *) values. The first (void *) actually points
+** to a function of type (int (*)(void *)). In order to invoke the connections
+** busy-handler, this function should be invoked with the second (void *) in
+** the array as the only argument. If it returns non-zero, then the operation
+** should be retried. If it returns zero, the custom VFS should abandon the
+** current operation.
+**
+**
- [[SQLITE_FCNTL_TEMPFILENAME]]
+** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
+** to have SQLite generate a
+** temporary filename using the same algorithm that is followed to generate
+** temporary filenames for TEMP tables and other internal uses. The
+** argument should be a char** which will be filled with the filename
+** written into memory obtained from [sqlite3_malloc()]. The caller should
+** invoke [sqlite3_free()] on the result to avoid a memory leak.
+**
+**
- [[SQLITE_FCNTL_MMAP_SIZE]]
+** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
+** maximum number of bytes that will be used for memory-mapped I/O.
+** The argument is a pointer to a value of type sqlite3_int64 that
+** is an advisory maximum number of bytes in the file to memory map. The
+** pointer is overwritten with the old value. The limit is not changed if
+** the value originally pointed to is negative, and so the current limit
+** can be queried by passing in a pointer to a negative number. This
+** file-control is used internally to implement [PRAGMA mmap_size].
+**
+**
- [[SQLITE_FCNTL_TRACE]]
+** The [SQLITE_FCNTL_TRACE] file control provides advisory information
+** to the VFS about what the higher layers of the SQLite stack are doing.
+** This file control is used by some VFS activity tracing [shims].
+** The argument is a zero-terminated string. Higher layers in the
+** SQLite stack may generate instances of this file control if
+** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
+**
+**
- [[SQLITE_FCNTL_HAS_MOVED]]
+** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
+** pointer to an integer and it writes a boolean into that integer depending
+** on whether or not the file has been renamed, moved, or deleted since it
+** was first opened.
+**
+**
- [[SQLITE_FCNTL_WIN32_SET_HANDLE]]
+** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
+** opcode causes the xFileControl method to swap the file handle with the one
+** pointed to by the pArg argument. This capability is used during testing
+** and only needs to be supported when SQLITE_TEST is defined.
+**
+**
+*/
+#define SQLITE_FCNTL_LOCKSTATE 1
+#define SQLITE_GET_LOCKPROXYFILE 2
+#define SQLITE_SET_LOCKPROXYFILE 3
+#define SQLITE_LAST_ERRNO 4
+#define SQLITE_FCNTL_SIZE_HINT 5
+#define SQLITE_FCNTL_CHUNK_SIZE 6
+#define SQLITE_FCNTL_FILE_POINTER 7
+#define SQLITE_FCNTL_SYNC_OMITTED 8
+#define SQLITE_FCNTL_WIN32_AV_RETRY 9
+#define SQLITE_FCNTL_PERSIST_WAL 10
+#define SQLITE_FCNTL_OVERWRITE 11
+#define SQLITE_FCNTL_VFSNAME 12
+#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
+#define SQLITE_FCNTL_PRAGMA 14
+#define SQLITE_FCNTL_BUSYHANDLER 15
+#define SQLITE_FCNTL_TEMPFILENAME 16
+#define SQLITE_FCNTL_MMAP_SIZE 18
+#define SQLITE_FCNTL_TRACE 19
+#define SQLITE_FCNTL_HAS_MOVED 20
+#define SQLITE_FCNTL_SYNC 21
+#define SQLITE_FCNTL_COMMIT_PHASETWO 22
+#define SQLITE_FCNTL_WIN32_SET_HANDLE 23
+
+/*
+** CAPI3REF: Mutex Handle
+**
+** The mutex module within SQLite defines [sqlite3_mutex] to be an
+** abstract type for a mutex object. The SQLite core never looks
+** at the internal representation of an [sqlite3_mutex]. It only
+** deals with pointers to the [sqlite3_mutex] object.
+**
+** Mutexes are created using [sqlite3_mutex_alloc()].
+*/
+typedef struct sqlite3_mutex sqlite3_mutex;
+
+/*
+** CAPI3REF: OS Interface Object
+**
+** An instance of the sqlite3_vfs object defines the interface between
+** the SQLite core and the underlying operating system. The "vfs"
+** in the name of the object stands for "virtual file system". See
+** the [VFS | VFS documentation] for further information.
+**
+** The value of the iVersion field is initially 1 but may be larger in
+** future versions of SQLite. Additional fields may be appended to this
+** object when the iVersion value is increased. Note that the structure
+** of the sqlite3_vfs object changes in the transaction between
+** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
+** modified.
+**
+** The szOsFile field is the size of the subclassed [sqlite3_file]
+** structure used by this VFS. mxPathname is the maximum length of
+** a pathname in this VFS.
+**
+** Registered sqlite3_vfs objects are kept on a linked list formed by
+** the pNext pointer. The [sqlite3_vfs_register()]
+** and [sqlite3_vfs_unregister()] interfaces manage this list
+** in a thread-safe way. The [sqlite3_vfs_find()] interface
+** searches the list. Neither the application code nor the VFS
+** implementation should use the pNext pointer.
+**
+** The pNext field is the only field in the sqlite3_vfs
+** structure that SQLite will ever modify. SQLite will only access
+** or modify this field while holding a particular static mutex.
+** The application should never modify anything within the sqlite3_vfs
+** object once the object has been registered.
+**
+** The zName field holds the name of the VFS module. The name must
+** be unique across all VFS modules.
+**
+** [[sqlite3_vfs.xOpen]]
+** ^SQLite guarantees that the zFilename parameter to xOpen
+** is either a NULL pointer or string obtained
+** from xFullPathname() with an optional suffix added.
+** ^If a suffix is added to the zFilename parameter, it will
+** consist of a single "-" character followed by no more than
+** 11 alphanumeric and/or "-" characters.
+** ^SQLite further guarantees that
+** the string will be valid and unchanged until xClose() is
+** called. Because of the previous sentence,
+** the [sqlite3_file] can safely store a pointer to the
+** filename if it needs to remember the filename for some reason.
+** If the zFilename parameter to xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file. ^Whenever the
+** xFilename parameter is NULL it will also be the case that the
+** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
+**
+** The flags argument to xOpen() includes all bits set in
+** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
+** or [sqlite3_open16()] is used, then flags includes at least
+** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
+** If xOpen() opens a file read-only then it sets *pOutFlags to
+** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
+**
+** ^(SQLite will also add one of the following flags to the xOpen()
+** call, depending on the object being opened:
+**
+**
+** - [SQLITE_OPEN_MAIN_DB]
+**
- [SQLITE_OPEN_MAIN_JOURNAL]
+**
- [SQLITE_OPEN_TEMP_DB]
+**
- [SQLITE_OPEN_TEMP_JOURNAL]
+**
- [SQLITE_OPEN_TRANSIENT_DB]
+**
- [SQLITE_OPEN_SUBJOURNAL]
+**
- [SQLITE_OPEN_MASTER_JOURNAL]
+**
- [SQLITE_OPEN_WAL]
+**
)^
+**
+** The file I/O implementation can use the object type flags to
+** change the way it deals with files. For example, an application
+** that does not care about crash recovery or rollback might make
+** the open of a journal file a no-op. Writes to this journal would
+** also be no-ops, and any attempt to read the journal would return
+** SQLITE_IOERR. Or the implementation might recognize that a database
+** file will be doing page-aligned sector reads and writes in a random
+** order and set up its I/O subsystem accordingly.
+**
+** SQLite might also add one of the following flags to the xOpen method:
+**
+**
+** - [SQLITE_OPEN_DELETEONCLOSE]
+**
- [SQLITE_OPEN_EXCLUSIVE]
+**
+**
+** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
+** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP databases and their journals, transient
+** databases, and subjournals.
+**
+** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** with the [SQLITE_OPEN_CREATE] flag, which are both directly
+** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
+** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
+** SQLITE_OPEN_CREATE, is used to indicate that file should always
+** be created, and that it is an error if it already exists.
+** It is not used to indicate the file should be opened
+** for exclusive access.
+**
+** ^At least szOsFile bytes of memory are allocated by SQLite
+** to hold the [sqlite3_file] structure passed as the third
+** argument to xOpen. The xOpen method does not have to
+** allocate the structure; it should just fill it in. Note that
+** the xOpen method must set the sqlite3_file.pMethods to either
+** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
+** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
+** element will be valid after xOpen returns regardless of the success
+** or failure of the xOpen call.
+**
+** [[sqlite3_vfs.xAccess]]
+** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
+** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
+** to test whether a file is at least readable. The file can be a
+** directory.
+**
+** ^SQLite will always allocate at least mxPathname+1 bytes for the
+** output buffer xFullPathname. The exact size of the output buffer
+** is also passed as a parameter to both methods. If the output buffer
+** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
+** handled as a fatal error by SQLite, vfs implementations should endeavor
+** to prevent this by setting mxPathname to a sufficiently large value.
+**
+** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
+** interfaces are not strictly a part of the filesystem, but they are
+** included in the VFS structure for completeness.
+** The xRandomness() function attempts to return nBytes bytes
+** of good-quality randomness into zOut. The return value is
+** the actual number of bytes of randomness obtained.
+** The xSleep() method causes the calling thread to sleep for at
+** least the number of microseconds given. ^The xCurrentTime()
+** method returns a Julian Day Number for the current date and time as
+** a floating point value.
+** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
+** Day Number multiplied by 86400000 (the number of milliseconds in
+** a 24-hour day).
+** ^SQLite will use the xCurrentTimeInt64() method to get the current
+** date and time if that method is available (if iVersion is 2 or
+** greater and the function pointer is not NULL) and will fall back
+** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
+**
+** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
+** are not used by the SQLite core. These optional interfaces are provided
+** by some VFSes to facilitate testing of the VFS code. By overriding
+** system calls with functions under its control, a test program can
+** simulate faults and error conditions that would otherwise be difficult
+** or impossible to induce. The set of system calls that can be overridden
+** varies from one VFS to another, and from one version of the same VFS to the
+** next. Applications that use these interfaces must be prepared for any
+** or all of these interfaces to be NULL or for their behavior to change
+** from one release to the next. Applications must not attempt to access
+** any of these methods if the iVersion of the VFS is less than 3.
+*/
+typedef struct sqlite3_vfs sqlite3_vfs;
+typedef void (*sqlite3_syscall_ptr)(void);
+struct sqlite3_vfs {
+ int iVersion; /* Structure version number (currently 3) */
+ int szOsFile; /* Size of subclassed sqlite3_file */
+ int mxPathname; /* Maximum file pathname length */
+ sqlite3_vfs *pNext; /* Next registered VFS */
+ const char *zName; /* Name of this virtual file system */
+ void *pAppData; /* Pointer to application-specific data */
+ int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
+ int flags, int *pOutFlags);
+ int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
+ int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
+ int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
+ void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
+ void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
+ void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
+ void (*xDlClose)(sqlite3_vfs*, void*);
+ int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
+ int (*xSleep)(sqlite3_vfs*, int microseconds);
+ int (*xCurrentTime)(sqlite3_vfs*, double*);
+ int (*xGetLastError)(sqlite3_vfs*, int, char *);
+ /*
+ ** The methods above are in version 1 of the sqlite_vfs object
+ ** definition. Those that follow are added in version 2 or later
+ */
+ int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
+ /*
+ ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
+ ** Those below are for version 3 and greater.
+ */
+ int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
+ sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
+ const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
+ /*
+ ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
+ ** New fields may be appended in figure versions. The iVersion
+ ** value will increment whenever this happens.
+ */
+};
+
+/*
+** CAPI3REF: Flags for the xAccess VFS method
+**
+** These integer constants can be used as the third parameter to
+** the xAccess method of an [sqlite3_vfs] object. They determine
+** what kind of permissions the xAccess method is looking for.
+** With SQLITE_ACCESS_EXISTS, the xAccess method
+** simply checks whether the file exists.
+** With SQLITE_ACCESS_READWRITE, the xAccess method
+** checks whether the named directory is both readable and writable
+** (in other words, if files can be added, removed, and renamed within
+** the directory).
+** The SQLITE_ACCESS_READWRITE constant is currently used only by the
+** [temp_store_directory pragma], though this could change in a future
+** release of SQLite.
+** With SQLITE_ACCESS_READ, the xAccess method
+** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
+** currently unused, though it might be used in a future release of
+** SQLite.
+*/
+#define SQLITE_ACCESS_EXISTS 0
+#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
+#define SQLITE_ACCESS_READ 2 /* Unused */
+
+/*
+** CAPI3REF: Flags for the xShmLock VFS method
+**
+** These integer constants define the various locking operations
+** allowed by the xShmLock method of [sqlite3_io_methods]. The
+** following are the only legal combinations of flags to the
+** xShmLock method:
+**
+**
+** - SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
+**
- SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
+**
- SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
+**
- SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
+**
+**
+** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
+** was given no the corresponding lock.
+**
+** The xShmLock method can transition between unlocked and SHARED or
+** between unlocked and EXCLUSIVE. It cannot transition between SHARED
+** and EXCLUSIVE.
+*/
+#define SQLITE_SHM_UNLOCK 1
+#define SQLITE_SHM_LOCK 2
+#define SQLITE_SHM_SHARED 4
+#define SQLITE_SHM_EXCLUSIVE 8
+
+/*
+** CAPI3REF: Maximum xShmLock index
+**
+** The xShmLock method on [sqlite3_io_methods] may use values
+** between 0 and this upper bound as its "offset" argument.
+** The SQLite core will never attempt to acquire or release a
+** lock outside of this range
+*/
+#define SQLITE_SHM_NLOCK 8
+
+
+/*
+** CAPI3REF: Initialize The SQLite Library
+**
+** ^The sqlite3_initialize() routine initializes the
+** SQLite library. ^The sqlite3_shutdown() routine
+** deallocates any resources that were allocated by sqlite3_initialize().
+** These routines are designed to aid in process initialization and
+** shutdown on embedded systems. Workstation applications using
+** SQLite normally do not need to invoke either of these routines.
+**
+** A call to sqlite3_initialize() is an "effective" call if it is
+** the first time sqlite3_initialize() is invoked during the lifetime of
+** the process, or if it is the first time sqlite3_initialize() is invoked
+** following a call to sqlite3_shutdown(). ^(Only an effective call
+** of sqlite3_initialize() does any initialization. All other calls
+** are harmless no-ops.)^
+**
+** A call to sqlite3_shutdown() is an "effective" call if it is the first
+** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
+** an effective call to sqlite3_shutdown() does any deinitialization.
+** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
+**
+** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
+** is not. The sqlite3_shutdown() interface must only be called from a
+** single thread. All open [database connections] must be closed and all
+** other SQLite resources must be deallocated prior to invoking
+** sqlite3_shutdown().
+**
+** Among other things, ^sqlite3_initialize() will invoke
+** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
+** will invoke sqlite3_os_end().
+**
+** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
+** ^If for some reason, sqlite3_initialize() is unable to initialize
+** the library (perhaps it is unable to allocate a needed resource such
+** as a mutex) it returns an [error code] other than [SQLITE_OK].
+**
+** ^The sqlite3_initialize() routine is called internally by many other
+** SQLite interfaces so that an application usually does not need to
+** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
+** calls sqlite3_initialize() so the SQLite library will be automatically
+** initialized when [sqlite3_open()] is called if it has not be initialized
+** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
+** compile-time option, then the automatic calls to sqlite3_initialize()
+** are omitted and the application must call sqlite3_initialize() directly
+** prior to using any other SQLite interface. For maximum portability,
+** it is recommended that applications always invoke sqlite3_initialize()
+** directly prior to using any other SQLite interface. Future releases
+** of SQLite may require this. In other words, the behavior exhibited
+** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
+** default behavior in some future release of SQLite.
+**
+** The sqlite3_os_init() routine does operating-system specific
+** initialization of the SQLite library. The sqlite3_os_end()
+** routine undoes the effect of sqlite3_os_init(). Typical tasks
+** performed by these routines include allocation or deallocation
+** of static resources, initialization of global variables,
+** setting up a default [sqlite3_vfs] module, or setting up
+** a default configuration using [sqlite3_config()].
+**
+** The application should never invoke either sqlite3_os_init()
+** or sqlite3_os_end() directly. The application should only invoke
+** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
+** interface is called automatically by sqlite3_initialize() and
+** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
+** implementations for sqlite3_os_init() and sqlite3_os_end()
+** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
+** When [custom builds | built for other platforms]
+** (using the [SQLITE_OS_OTHER=1] compile-time
+** option) the application must supply a suitable implementation for
+** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
+** implementation of sqlite3_os_init() or sqlite3_os_end()
+** must return [SQLITE_OK] on success and some other [error code] upon
+** failure.
+*/
+SQLITE_API int sqlite3_initialize(void);
+SQLITE_API int sqlite3_shutdown(void);
+SQLITE_API int sqlite3_os_init(void);
+SQLITE_API int sqlite3_os_end(void);
+
+/*
+** CAPI3REF: Configuring The SQLite Library
+**
+** The sqlite3_config() interface is used to make global configuration
+** changes to SQLite in order to tune SQLite to the specific needs of
+** the application. The default configuration is recommended for most
+** applications and so this routine is usually not necessary. It is
+** provided to support rare applications with unusual needs.
+**
+** The sqlite3_config() interface is not threadsafe. The application
+** must insure that no other SQLite interfaces are invoked by other
+** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
+** may only be invoked prior to library initialization using
+** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
+** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
+** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
+** Note, however, that ^sqlite3_config() can be called as part of the
+** implementation of an application-defined [sqlite3_os_init()].
+**
+** The first argument to sqlite3_config() is an integer
+** [configuration option] that determines
+** what property of SQLite is to be configured. Subsequent arguments
+** vary depending on the [configuration option]
+** in the first argument.
+**
+** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
+** ^If the option is unknown or SQLite is unable to set the option
+** then this routine returns a non-zero [error code].
+*/
+SQLITE_API int sqlite3_config(int, ...);
+
+/*
+** CAPI3REF: Configure database connections
+**
+** The sqlite3_db_config() interface is used to make configuration
+** changes to a [database connection]. The interface is similar to
+** [sqlite3_config()] except that the changes apply to a single
+** [database connection] (specified in the first argument).
+**
+** The second argument to sqlite3_db_config(D,V,...) is the
+** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
+** that indicates what aspect of the [database connection] is being configured.
+** Subsequent arguments vary depending on the configuration verb.
+**
+** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
+** the call is considered successful.
+*/
+SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Memory Allocation Routines
+**
+** An instance of this object defines the interface between SQLite
+** and low-level memory allocation routines.
+**
+** This object is used in only one place in the SQLite interface.
+** A pointer to an instance of this object is the argument to
+** [sqlite3_config()] when the configuration option is
+** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
+** By creating an instance of this object
+** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
+** during configuration, an application can specify an alternative
+** memory allocation subsystem for SQLite to use for all of its
+** dynamic memory needs.
+**
+** Note that SQLite comes with several [built-in memory allocators]
+** that are perfectly adequate for the overwhelming majority of applications
+** and that this object is only useful to a tiny minority of applications
+** with specialized memory allocation requirements. This object is
+** also used during testing of SQLite in order to specify an alternative
+** memory allocator that simulates memory out-of-memory conditions in
+** order to verify that SQLite recovers gracefully from such
+** conditions.
+**
+** The xMalloc, xRealloc, and xFree methods must work like the
+** malloc(), realloc() and free() functions from the standard C library.
+** ^SQLite guarantees that the second argument to
+** xRealloc is always a value returned by a prior call to xRoundup.
+**
+** xSize should return the allocated size of a memory allocation
+** previously obtained from xMalloc or xRealloc. The allocated size
+** is always at least as big as the requested size but may be larger.
+**
+** The xRoundup method returns what would be the allocated size of
+** a memory allocation given a particular requested size. Most memory
+** allocators round up memory allocations at least to the next multiple
+** of 8. Some allocators round up to a larger multiple or to a power of 2.
+** Every memory allocation request coming in through [sqlite3_malloc()]
+** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
+** that causes the corresponding memory allocation to fail.
+**
+** The xInit method initializes the memory allocator. For example,
+** it might allocate any require mutexes or initialize internal data
+** structures. The xShutdown method is invoked (indirectly) by
+** [sqlite3_shutdown()] and should deallocate any resources acquired
+** by xInit. The pAppData pointer is used as the only parameter to
+** xInit and xShutdown.
+**
+** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
+** the xInit method, so the xInit method need not be threadsafe. The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either. For all other methods, SQLite
+** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
+** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
+** it is by default) and so the methods are automatically serialized.
+** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
+** methods must be threadsafe or else make their own arrangements for
+** serialization.
+**
+** SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+*/
+typedef struct sqlite3_mem_methods sqlite3_mem_methods;
+struct sqlite3_mem_methods {
+ void *(*xMalloc)(int); /* Memory allocation function */
+ void (*xFree)(void*); /* Free a prior allocation */
+ void *(*xRealloc)(void*,int); /* Resize an allocation */
+ int (*xSize)(void*); /* Return the size of an allocation */
+ int (*xRoundup)(int); /* Round up request size to allocation size */
+ int (*xInit)(void*); /* Initialize the memory allocator */
+ void (*xShutdown)(void*); /* Deinitialize the memory allocator */
+ void *pAppData; /* Argument to xInit() and xShutdown() */
+};
+
+/*
+** CAPI3REF: Configuration Options
+** KEYWORDS: {configuration option}
+**
+** These constants are the available integer configuration options that
+** can be passed as the first argument to the [sqlite3_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued. Applications
+** should check the return code from [sqlite3_config()] to make sure that
+** the call worked. The [sqlite3_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+**
+** [[SQLITE_CONFIG_SINGLETHREAD]] - SQLITE_CONFIG_SINGLETHREAD
+** - There are no arguments to this option. ^This option sets the
+** [threading mode] to Single-thread. In other words, it disables
+** all mutexing and puts SQLite into a mode where it can only be used
+** by a single thread. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to change the [threading mode] from its default
+** value of Single-thread and so [sqlite3_config()] will return
+** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
+** configuration option.
+**
+** [[SQLITE_CONFIG_MULTITHREAD]] - SQLITE_CONFIG_MULTITHREAD
+** - There are no arguments to this option. ^This option sets the
+** [threading mode] to Multi-thread. In other words, it disables
+** mutexing on [database connection] and [prepared statement] objects.
+** The application is responsible for serializing access to
+** [database connections] and [prepared statements]. But other mutexes
+** are enabled so that SQLite will be safe to use in a multi-threaded
+** environment as long as no two threads attempt to use the same
+** [database connection] at the same time. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to set the Multi-thread [threading mode] and
+** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
+** SQLITE_CONFIG_MULTITHREAD configuration option.
+**
+** [[SQLITE_CONFIG_SERIALIZED]] - SQLITE_CONFIG_SERIALIZED
+** - There are no arguments to this option. ^This option sets the
+** [threading mode] to Serialized. In other words, this option enables
+** all mutexes including the recursive
+** mutexes on [database connection] and [prepared statement] objects.
+** In this mode (which is the default when SQLite is compiled with
+** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
+** to [database connections] and [prepared statements] so that the
+** application is free to use the same [database connection] or the
+** same [prepared statement] in different threads at the same time.
+** ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to set the Serialized [threading mode] and
+** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
+** SQLITE_CONFIG_SERIALIZED configuration option.
+**
+** [[SQLITE_CONFIG_MALLOC]] - SQLITE_CONFIG_MALLOC
+** - ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure. The argument specifies
+** alternative low-level memory allocation routines to be used in place of
+** the memory allocation routines built into SQLite.)^ ^SQLite makes
+** its own private copy of the content of the [sqlite3_mem_methods] structure
+** before the [sqlite3_config()] call returns.
+**
+** [[SQLITE_CONFIG_GETMALLOC]] - SQLITE_CONFIG_GETMALLOC
+** - ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
+** structure is filled with the currently defined memory allocation routines.)^
+** This option can be used to overload the default memory allocation
+** routines with a wrapper that simulations memory allocation failure or
+** tracks memory usage, for example.
+**
+** [[SQLITE_CONFIG_MEMSTATUS]] - SQLITE_CONFIG_MEMSTATUS
+** - ^This option takes single argument of type int, interpreted as a
+** boolean, which enables or disables the collection of memory allocation
+** statistics. ^(When memory allocation statistics are disabled, the
+** following SQLite interfaces become non-operational:
+**
+** - [sqlite3_memory_used()]
+**
- [sqlite3_memory_highwater()]
+**
- [sqlite3_soft_heap_limit64()]
+**
- [sqlite3_status()]
+**
)^
+** ^Memory allocation statistics are enabled by default unless SQLite is
+** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
+** allocation statistics are disabled by default.
+**
+**
+** [[SQLITE_CONFIG_SCRATCH]] - SQLITE_CONFIG_SCRATCH
+** - ^This option specifies a static memory buffer that SQLite can use for
+** scratch memory. There are three arguments: A pointer an 8-byte
+** aligned memory buffer from which the scratch allocations will be
+** drawn, the size of each scratch allocation (sz),
+** and the maximum number of scratch allocations (N). The sz
+** argument must be a multiple of 16.
+** The first argument must be a pointer to an 8-byte aligned buffer
+** of at least sz*N bytes of memory.
+** ^SQLite will use no more than two scratch buffers per thread. So
+** N should be set to twice the expected maximum number of threads.
+** ^SQLite will never require a scratch buffer that is more than 6
+** times the database page size. ^If SQLite needs needs additional
+** scratch memory beyond what is provided by this configuration option, then
+** [sqlite3_malloc()] will be used to obtain the memory needed.
+**
+** [[SQLITE_CONFIG_PAGECACHE]] - SQLITE_CONFIG_PAGECACHE
+** - ^This option specifies a static memory buffer that SQLite can use for
+** the database page cache with the default page cache implementation.
+** This configuration should not be used if an application-define page
+** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
+** There are three arguments to this option: A pointer to 8-byte aligned
+** memory, the size of each page buffer (sz), and the number of pages (N).
+** The sz argument should be the size of the largest database page
+** (a power of two between 512 and 32768) plus a little extra for each
+** page header. ^The page header size is 20 to 40 bytes depending on
+** the host architecture. ^It is harmless, apart from the wasted memory,
+** to make sz a little too large. The first
+** argument should point to an allocation of at least sz*N bytes of memory.
+** ^SQLite will use the memory provided by the first argument to satisfy its
+** memory needs for the first N pages that it adds to cache. ^If additional
+** page cache memory is needed beyond what is provided by this option, then
+** SQLite goes to [sqlite3_malloc()] for the additional storage space.
+** The pointer in the first argument must
+** be aligned to an 8-byte boundary or subsequent behavior of SQLite
+** will be undefined.
+**
+** [[SQLITE_CONFIG_HEAP]] - SQLITE_CONFIG_HEAP
+** - ^This option specifies a static memory buffer that SQLite will use
+** for all of its dynamic memory allocation needs beyond those provided
+** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
+** There are three arguments: An 8-byte aligned pointer to the memory,
+** the number of bytes in the memory buffer, and the minimum allocation size.
+** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
+** to using its default memory allocator (the system malloc() implementation),
+** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
+** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
+** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
+** allocator is engaged to handle all of SQLites memory allocation needs.
+** The first pointer (the memory pointer) must be aligned to an 8-byte
+** boundary or subsequent behavior of SQLite will be undefined.
+** The minimum allocation size is capped at 2**12. Reasonable values
+** for the minimum allocation size are 2**5 through 2**8.
+**
+** [[SQLITE_CONFIG_MUTEX]] - SQLITE_CONFIG_MUTEX
+** - ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure. The argument specifies
+** alternative low-level mutex routines to be used in place
+** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
+** content of the [sqlite3_mutex_methods] structure before the call to
+** [sqlite3_config()] returns. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** the entire mutexing subsystem is omitted from the build and hence calls to
+** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
+** return [SQLITE_ERROR].
+**
+** [[SQLITE_CONFIG_GETMUTEX]] - SQLITE_CONFIG_GETMUTEX
+** - ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure. The
+** [sqlite3_mutex_methods]
+** structure is filled with the currently defined mutex routines.)^
+** This option can be used to overload the default mutex allocation
+** routines with a wrapper used to track mutex usage for performance
+** profiling or testing, for example. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** the entire mutexing subsystem is omitted from the build and hence calls to
+** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
+** return [SQLITE_ERROR].
+**
+** [[SQLITE_CONFIG_LOOKASIDE]] - SQLITE_CONFIG_LOOKASIDE
+** - ^(This option takes two arguments that determine the default
+** memory allocation for the lookaside memory allocator on each
+** [database connection]. The first argument is the
+** size of each lookaside buffer slot and the second is the number of
+** slots allocated to each database connection.)^ ^(This option sets the
+** default lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
+** verb to [sqlite3_db_config()] can be used to change the lookaside
+** configuration on individual connections.)^
+**
+** [[SQLITE_CONFIG_PCACHE2]] - SQLITE_CONFIG_PCACHE2
+** - ^(This option takes a single argument which is a pointer to
+** an [sqlite3_pcache_methods2] object. This object specifies the interface
+** to a custom page cache implementation.)^ ^SQLite makes a copy of the
+** object and uses it for page cache memory allocations.
+**
+** [[SQLITE_CONFIG_GETPCACHE2]] - SQLITE_CONFIG_GETPCACHE2
+** - ^(This option takes a single argument which is a pointer to an
+** [sqlite3_pcache_methods2] object. SQLite copies of the current
+** page cache implementation into that object.)^
+**
+** [[SQLITE_CONFIG_LOG]] - SQLITE_CONFIG_LOG
+** - The SQLITE_CONFIG_LOG option is used to configure the SQLite
+** global [error log].
+** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
+** function with a call signature of void(*)(void*,int,const char*),
+** and a pointer to void. ^If the function pointer is not NULL, it is
+** invoked by [sqlite3_log()] to process each logging event. ^If the
+** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
+** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
+** passed through as the first parameter to the application-defined logger
+** function whenever that function is invoked. ^The second parameter to
+** the logger function is a copy of the first parameter to the corresponding
+** [sqlite3_log()] call and is intended to be a [result code] or an
+** [extended result code]. ^The third parameter passed to the logger is
+** log message after formatting via [sqlite3_snprintf()].
+** The SQLite logging interface is not reentrant; the logger function
+** supplied by the application must not invoke any SQLite interface.
+** In a multi-threaded application, the application-defined logger
+** function must be threadsafe.
+**
+** [[SQLITE_CONFIG_URI]] - SQLITE_CONFIG_URI
+**
- ^(This option takes a single argument of type int. If non-zero, then
+** URI handling is globally enabled. If the parameter is zero, then URI handling
+** is globally disabled.)^ ^If URI handling is globally enabled, all filenames
+** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
+** specified as part of [ATTACH] commands are interpreted as URIs, regardless
+** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
+** connection is opened. ^If it is globally disabled, filenames are
+** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
+** database connection is opened. ^(By default, URI handling is globally
+** disabled. The default value may be changed by compiling with the
+** [SQLITE_USE_URI] symbol defined.)^
+**
+** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]]
- SQLITE_CONFIG_COVERING_INDEX_SCAN
+**
- ^This option takes a single integer argument which is interpreted as
+** a boolean in order to enable or disable the use of covering indices for
+** full table scans in the query optimizer. ^The default setting is determined
+** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
+** if that compile-time option is omitted.
+** The ability to disable the use of covering indices for full table scans
+** is because some incorrectly coded legacy applications might malfunction
+** when the optimization is enabled. Providing the ability to
+** disable the optimization allows the older, buggy application code to work
+** without change even with newer versions of SQLite.
+**
+** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
+**
- SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
+**
- These options are obsolete and should not be used by new code.
+** They are retained for backwards compatibility but are now no-ops.
+**
+**
+** [[SQLITE_CONFIG_SQLLOG]]
+** - SQLITE_CONFIG_SQLLOG
+**
- This option is only available if sqlite is compiled with the
+** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
+** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
+** The second should be of type (void*). The callback is invoked by the library
+** in three separate circumstances, identified by the value passed as the
+** fourth parameter. If the fourth parameter is 0, then the database connection
+** passed as the second argument has just been opened. The third argument
+** points to a buffer containing the name of the main database file. If the
+** fourth parameter is 1, then the SQL statement that the third parameter
+** points to has just been executed. Or, if the fourth parameter is 2, then
+** the connection being passed as the second parameter is being closed. The
+** third parameter is passed NULL In this case. An example of using this
+** configuration option can be seen in the "test_sqllog.c" source file in
+** the canonical SQLite source tree.
+**
+** [[SQLITE_CONFIG_MMAP_SIZE]]
+** - SQLITE_CONFIG_MMAP_SIZE
+**
- ^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
+** that are the default mmap size limit (the default setting for
+** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
+** ^The default setting can be overridden by each database connection using
+** either the [PRAGMA mmap_size] command, or by using the
+** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
+** cannot be changed at run-time. Nor may the maximum allowed mmap size
+** exceed the compile-time maximum mmap size set by the
+** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
+** ^If either argument to this option is negative, then that argument is
+** changed to its compile-time default.
+**
+** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
+**
- SQLITE_CONFIG_WIN32_HEAPSIZE
+**
- ^This option is only available if SQLite is compiled for Windows
+** with the [SQLITE_WIN32_MALLOC] pre-processor macro defined.
+** SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
+** that specifies the maximum size of the created heap.
+**
+*/
+#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
+#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
+#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
+#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
+#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
+#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
+#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
+#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
+#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
+/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
+#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
+#define SQLITE_CONFIG_PCACHE 14 /* no-op */
+#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
+#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
+#define SQLITE_CONFIG_URI 17 /* int */
+#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
+#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
+#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
+#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
+#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
+#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
+
+/*
+** CAPI3REF: Database Connection Configuration Options
+**
+** These constants are the available integer configuration options that
+** can be passed as the second argument to the [sqlite3_db_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued. Applications
+** should check the return code from [sqlite3_db_config()] to make sure that
+** the call worked. ^The [sqlite3_db_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+**
+** - SQLITE_DBCONFIG_LOOKASIDE
+** - ^This option takes three additional arguments that determine the
+** [lookaside memory allocator] configuration for the [database connection].
+** ^The first argument (the third parameter to [sqlite3_db_config()] is a
+** pointer to a memory buffer to use for lookaside memory.
+** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
+** may be NULL in which case SQLite will allocate the
+** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
+** size of each lookaside buffer slot. ^The third argument is the number of
+** slots. The size of the buffer in the first argument must be greater than
+** or equal to the product of the second and third arguments. The buffer
+** must be aligned to an 8-byte boundary. ^If the second argument to
+** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
+** rounded down to the next smaller multiple of 8. ^(The lookaside memory
+** configuration for a database connection can only be changed when that
+** connection is not currently using lookaside memory, or in other words
+** when the "current value" returned by
+** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
+** Any attempt to change the lookaside memory configuration when lookaside
+** memory is in use leaves the configuration unchanged and returns
+** [SQLITE_BUSY].)^
+**
+** - SQLITE_DBCONFIG_ENABLE_FKEY
+** - ^This option is used to enable or disable the enforcement of
+** [foreign key constraints]. There should be two additional arguments.
+** The first argument is an integer which is 0 to disable FK enforcement,
+** positive to enable FK enforcement or negative to leave FK enforcement
+** unchanged. The second parameter is a pointer to an integer into which
+** is written 0 or 1 to indicate whether FK enforcement is off or on
+** following this call. The second parameter may be a NULL pointer, in
+** which case the FK enforcement setting is not reported back.
+**
+** - SQLITE_DBCONFIG_ENABLE_TRIGGER
+** - ^This option is used to enable or disable [CREATE TRIGGER | triggers].
+** There should be two additional arguments.
+** The first argument is an integer which is 0 to disable triggers,
+** positive to enable triggers or negative to leave the setting unchanged.
+** The second parameter is a pointer to an integer into which
+** is written 0 or 1 to indicate whether triggers are disabled or enabled
+** following this call. The second parameter may be a NULL pointer, in
+** which case the trigger setting is not reported back.
+**
+**
+*/
+#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
+#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
+#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
+
+
+/*
+** CAPI3REF: Enable Or Disable Extended Result Codes
+**
+** ^The sqlite3_extended_result_codes() routine enables or disables the
+** [extended result codes] feature of SQLite. ^The extended result
+** codes are disabled by default for historical compatibility.
+*/
+SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
+
+/*
+** CAPI3REF: Last Insert Rowid
+**
+** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
+** has a unique 64-bit signed
+** integer key called the [ROWID | "rowid"]. ^The rowid is always available
+** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
+** names are not also used by explicitly declared columns. ^If
+** the table has a column of type [INTEGER PRIMARY KEY] then that column
+** is another alias for the rowid.
+**
+** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the
+** most recent successful [INSERT] into a rowid table or [virtual table]
+** on database connection D.
+** ^Inserts into [WITHOUT ROWID] tables are not recorded.
+** ^If no successful [INSERT]s into rowid tables
+** have ever occurred on the database connection D,
+** then sqlite3_last_insert_rowid(D) returns zero.
+**
+** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
+** method, then this routine will return the [rowid] of the inserted
+** row as long as the trigger or virtual table method is running.
+** But once the trigger or virtual table method ends, the value returned
+** by this routine reverts to what it was before the trigger or virtual
+** table method began.)^
+**
+** ^An [INSERT] that fails due to a constraint violation is not a
+** successful [INSERT] and does not change the value returned by this
+** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
+** and INSERT OR ABORT make no changes to the return value of this
+** routine when their insertion fails. ^(When INSERT OR REPLACE
+** encounters a constraint violation, it does not fail. The
+** INSERT continues to completion after deleting rows that caused
+** the constraint problem so INSERT OR REPLACE will always change
+** the return value of this interface.)^
+**
+** ^For the purposes of this routine, an [INSERT] is considered to
+** be successful even if it is subsequently rolled back.
+**
+** This function is accessible to SQL statements via the
+** [last_insert_rowid() SQL function].
+**
+** If a separate thread performs a new [INSERT] on the same
+** database connection while the [sqlite3_last_insert_rowid()]
+** function is running and thus changes the last insert [rowid],
+** then the value returned by [sqlite3_last_insert_rowid()] is
+** unpredictable and might not equal either the old or the new
+** last insert [rowid].
+*/
+SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
+
+/*
+** CAPI3REF: Count The Number Of Rows Modified
+**
+** ^This function returns the number of database rows that were changed
+** or inserted or deleted by the most recently completed SQL statement
+** on the [database connection] specified by the first parameter.
+** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
+** or [DELETE] statement are counted. Auxiliary changes caused by
+** triggers or [foreign key actions] are not counted.)^ Use the
+** [sqlite3_total_changes()] function to find the total number of changes
+** including changes caused by triggers and foreign key actions.
+**
+** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
+** are not counted. Only real table changes are counted.
+**
+** ^(A "row change" is a change to a single row of a single table
+** caused by an INSERT, DELETE, or UPDATE statement. Rows that
+** are changed as side effects of [REPLACE] constraint resolution,
+** rollback, ABORT processing, [DROP TABLE], or by any other
+** mechanisms do not count as direct row changes.)^
+**
+** A "trigger context" is a scope of execution that begins and
+** ends with the script of a [CREATE TRIGGER | trigger].
+** Most SQL statements are
+** evaluated outside of any trigger. This is the "top level"
+** trigger context. If a trigger fires from the top level, a
+** new trigger context is entered for the duration of that one
+** trigger. Subtriggers create subcontexts for their duration.
+**
+** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
+** not create a new trigger context.
+**
+** ^This function returns the number of direct row changes in the
+** most recent INSERT, UPDATE, or DELETE statement within the same
+** trigger context.
+**
+** ^Thus, when called from the top level, this function returns the
+** number of changes in the most recent INSERT, UPDATE, or DELETE
+** that also occurred at the top level. ^(Within the body of a trigger,
+** the sqlite3_changes() interface can be called to find the number of
+** changes in the most recently completed INSERT, UPDATE, or DELETE
+** statement within the body of the same trigger.
+** However, the number returned does not include changes
+** caused by subtriggers since those have their own context.)^
+**
+** See also the [sqlite3_total_changes()] interface, the
+** [count_changes pragma], and the [changes() SQL function].
+**
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_changes()] is running then the value returned
+** is unpredictable and not meaningful.
+*/
+SQLITE_API int sqlite3_changes(sqlite3*);
+
+/*
+** CAPI3REF: Total Number Of Rows Modified
+**
+** ^This function returns the number of row changes caused by [INSERT],
+** [UPDATE] or [DELETE] statements since the [database connection] was opened.
+** ^(The count returned by sqlite3_total_changes() includes all changes
+** from all [CREATE TRIGGER | trigger] contexts and changes made by
+** [foreign key actions]. However,
+** the count does not include changes used to implement [REPLACE] constraints,
+** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
+** count does not include rows of views that fire an [INSTEAD OF trigger],
+** though if the INSTEAD OF trigger makes changes of its own, those changes
+** are counted.)^
+** ^The sqlite3_total_changes() function counts the changes as soon as
+** the statement that makes them is completed (when the statement handle
+** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
+**
+** See also the [sqlite3_changes()] interface, the
+** [count_changes pragma], and the [total_changes() SQL function].
+**
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_total_changes()] is running then the value
+** returned is unpredictable and not meaningful.
+*/
+SQLITE_API int sqlite3_total_changes(sqlite3*);
+
+/*
+** CAPI3REF: Interrupt A Long-Running Query
+**
+** ^This function causes any pending database operation to abort and
+** return at its earliest opportunity. This routine is typically
+** called in response to a user action such as pressing "Cancel"
+** or Ctrl-C where the user wants a long query operation to halt
+** immediately.
+**
+** ^It is safe to call this routine from a thread different from the
+** thread that is currently running the database operation. But it
+** is not safe to call this routine with a [database connection] that
+** is closed or might close before sqlite3_interrupt() returns.
+**
+** ^If an SQL operation is very nearly finished at the time when
+** sqlite3_interrupt() is called, then it might not have an opportunity
+** to be interrupted and might continue to completion.
+**
+** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
+** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
+** that is inside an explicit transaction, then the entire transaction
+** will be rolled back automatically.
+**
+** ^The sqlite3_interrupt(D) call is in effect until all currently running
+** SQL statements on [database connection] D complete. ^Any new SQL statements
+** that are started after the sqlite3_interrupt() call and before the
+** running statements reaches zero are interrupted as if they had been
+** running prior to the sqlite3_interrupt() call. ^New SQL statements
+** that are started after the running statement count reaches zero are
+** not effected by the sqlite3_interrupt().
+** ^A call to sqlite3_interrupt(D) that occurs when there are no running
+** SQL statements is a no-op and has no effect on SQL statements
+** that are started after the sqlite3_interrupt() call returns.
+**
+** If the database connection closes while [sqlite3_interrupt()]
+** is running then bad things will likely happen.
+*/
+SQLITE_API void sqlite3_interrupt(sqlite3*);
+
+/*
+** CAPI3REF: Determine If An SQL Statement Is Complete
+**
+** These routines are useful during command-line input to determine if the
+** currently entered text seems to form a complete SQL statement or
+** if additional input is needed before sending the text into
+** SQLite for parsing. ^These routines return 1 if the input string
+** appears to be a complete SQL statement. ^A statement is judged to be
+** complete if it ends with a semicolon token and is not a prefix of a
+** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
+** string literals or quoted identifier names or comments are not
+** independent tokens (they are part of the token in which they are
+** embedded) and thus do not count as a statement terminator. ^Whitespace
+** and comments that follow the final semicolon are ignored.
+**
+** ^These routines return 0 if the statement is incomplete. ^If a
+** memory allocation fails, then SQLITE_NOMEM is returned.
+**
+** ^These routines do not parse the SQL statements thus
+** will not detect syntactically incorrect SQL.
+**
+** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
+** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
+** automatically by sqlite3_complete16(). If that initialization fails,
+** then the return value from sqlite3_complete16() will be non-zero
+** regardless of whether or not the input SQL is complete.)^
+**
+** The input to [sqlite3_complete()] must be a zero-terminated
+** UTF-8 string.
+**
+** The input to [sqlite3_complete16()] must be a zero-terminated
+** UTF-16 string in native byte order.
+*/
+SQLITE_API int sqlite3_complete(const char *sql);
+SQLITE_API int sqlite3_complete16(const void *sql);
+
+/*
+** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
+**
+** ^This routine sets a callback function that might be invoked whenever
+** an attempt is made to open a database table that another thread
+** or process has locked.
+**
+** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
+** is returned immediately upon encountering the lock. ^If the busy callback
+** is not NULL, then the callback might be invoked with two arguments.
+**
+** ^The first argument to the busy handler is a copy of the void* pointer which
+** is the third argument to sqlite3_busy_handler(). ^The second argument to
+** the busy handler callback is the number of times that the busy handler has
+** been invoked for this locking event. ^If the
+** busy callback returns 0, then no additional attempts are made to
+** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
+** ^If the callback returns non-zero, then another attempt
+** is made to open the database for reading and the cycle repeats.
+**
+** The presence of a busy handler does not guarantee that it will be invoked
+** when there is lock contention. ^If SQLite determines that invoking the busy
+** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
+** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
+** Consider a scenario where one process is holding a read lock that
+** it is trying to promote to a reserved lock and
+** a second process is holding a reserved lock that it is trying
+** to promote to an exclusive lock. The first process cannot proceed
+** because it is blocked by the second and the second process cannot
+** proceed because it is blocked by the first. If both processes
+** invoke the busy handlers, neither will make any progress. Therefore,
+** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
+** will induce the first process to release its read lock and allow
+** the second process to proceed.
+**
+** ^The default busy callback is NULL.
+**
+** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
+** when SQLite is in the middle of a large transaction where all the
+** changes will not fit into the in-memory cache. SQLite will
+** already hold a RESERVED lock on the database file, but it needs
+** to promote this lock to EXCLUSIVE so that it can spill cache
+** pages into the database file without harm to concurrent
+** readers. ^If it is unable to promote the lock, then the in-memory
+** cache will be left in an inconsistent state and so the error
+** code is promoted from the relatively benign [SQLITE_BUSY] to
+** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
+** forces an automatic rollback of the changes. See the
+**
+** CorruptionFollowingBusyError wiki page for a discussion of why
+** this is important.
+**
+** ^(There can only be a single busy handler defined for each
+** [database connection]. Setting a new busy handler clears any
+** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
+** will also set or clear the busy handler.
+**
+** The busy callback should not take any actions which modify the
+** database connection that invoked the busy handler. Any such actions
+** result in undefined behavior.
+**
+** A busy handler must not close the database connection
+** or [prepared statement] that invoked the busy handler.
+*/
+SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
+
+/*
+** CAPI3REF: Set A Busy Timeout
+**
+** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
+** for a specified amount of time when a table is locked. ^The handler
+** will sleep multiple times until at least "ms" milliseconds of sleeping
+** have accumulated. ^After at least "ms" milliseconds of sleeping,
+** the handler returns 0 which causes [sqlite3_step()] to return
+** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
+**
+** ^Calling this routine with an argument less than or equal to zero
+** turns off all busy handlers.
+**
+** ^(There can only be a single busy handler for a particular
+** [database connection] any any given moment. If another busy handler
+** was defined (using [sqlite3_busy_handler()]) prior to calling
+** this routine, that other busy handler is cleared.)^
+*/
+SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
+
+/*
+** CAPI3REF: Convenience Routines For Running Queries
+**
+** This is a legacy interface that is preserved for backwards compatibility.
+** Use of this interface is not recommended.
+**
+** Definition: A result table is memory data structure created by the
+** [sqlite3_get_table()] interface. A result table records the
+** complete query results from one or more queries.
+**
+** The table conceptually has a number of rows and columns. But
+** these numbers are not part of the result table itself. These
+** numbers are obtained separately. Let N be the number of rows
+** and M be the number of columns.
+**
+** A result table is an array of pointers to zero-terminated UTF-8 strings.
+** There are (N+1)*M elements in the array. The first M pointers point
+** to zero-terminated strings that contain the names of the columns.
+** The remaining entries all point to query results. NULL values result
+** in NULL pointers. All other values are in their UTF-8 zero-terminated
+** string representation as returned by [sqlite3_column_text()].
+**
+** A result table might consist of one or more memory allocations.
+** It is not safe to pass a result table directly to [sqlite3_free()].
+** A result table should be deallocated using [sqlite3_free_table()].
+**
+** ^(As an example of the result table format, suppose a query result
+** is as follows:
+**
+**
+** Name | Age
+** -----------------------
+** Alice | 43
+** Bob | 28
+** Cindy | 21
+**
+**
+** There are two column (M==2) and three rows (N==3). Thus the
+** result table has 8 entries. Suppose the result table is stored
+** in an array names azResult. Then azResult holds this content:
+**
+**
+** azResult[0] = "Name";
+** azResult[1] = "Age";
+** azResult[2] = "Alice";
+** azResult[3] = "43";
+** azResult[4] = "Bob";
+** azResult[5] = "28";
+** azResult[6] = "Cindy";
+** azResult[7] = "21";
+**
)^
+**
+** ^The sqlite3_get_table() function evaluates one or more
+** semicolon-separated SQL statements in the zero-terminated UTF-8
+** string of its 2nd parameter and returns a result table to the
+** pointer given in its 3rd parameter.
+**
+** After the application has finished with the result from sqlite3_get_table(),
+** it must pass the result table pointer to sqlite3_free_table() in order to
+** release the memory that was malloced. Because of the way the
+** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
+** function must not try to call [sqlite3_free()] directly. Only
+** [sqlite3_free_table()] is able to release the memory properly and safely.
+**
+** The sqlite3_get_table() interface is implemented as a wrapper around
+** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
+** to any internal data structures of SQLite. It uses only the public
+** interface defined here. As a consequence, errors that occur in the
+** wrapper layer outside of the internal [sqlite3_exec()] call are not
+** reflected in subsequent calls to [sqlite3_errcode()] or
+** [sqlite3_errmsg()].
+*/
+SQLITE_API int sqlite3_get_table(
+ sqlite3 *db, /* An open database */
+ const char *zSql, /* SQL to be evaluated */
+ char ***pazResult, /* Results of the query */
+ int *pnRow, /* Number of result rows written here */
+ int *pnColumn, /* Number of result columns written here */
+ char **pzErrmsg /* Error msg written here */
+);
+SQLITE_API void sqlite3_free_table(char **result);
+
+/*
+** CAPI3REF: Formatted String Printing Functions
+**
+** These routines are work-alikes of the "printf()" family of functions
+** from the standard C library.
+**
+** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
+** results into memory obtained from [sqlite3_malloc()].
+** The strings returned by these two routines should be
+** released by [sqlite3_free()]. ^Both routines return a
+** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
+** memory to hold the resulting string.
+**
+** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
+** the standard C library. The result is written into the
+** buffer supplied as the second parameter whose size is given by
+** the first parameter. Note that the order of the
+** first two parameters is reversed from snprintf().)^ This is an
+** historical accident that cannot be fixed without breaking
+** backwards compatibility. ^(Note also that sqlite3_snprintf()
+** returns a pointer to its buffer instead of the number of
+** characters actually written into the buffer.)^ We admit that
+** the number of characters written would be a more useful return
+** value but we cannot change the implementation of sqlite3_snprintf()
+** now without breaking compatibility.
+**
+** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
+** guarantees that the buffer is always zero-terminated. ^The first
+** parameter "n" is the total size of the buffer, including space for
+** the zero terminator. So the longest string that can be completely
+** written will be n-1 characters.
+**
+** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
+**
+** These routines all implement some additional formatting
+** options that are useful for constructing SQL statements.
+** All of the usual printf() formatting options apply. In addition, there
+** is are "%q", "%Q", and "%z" options.
+**
+** ^(The %q option works like %s in that it substitutes a nul-terminated
+** string from the argument list. But %q also doubles every '\'' character.
+** %q is designed for use inside a string literal.)^ By doubling each '\''
+** character it escapes that character and allows it to be inserted into
+** the string.
+**
+** For example, assume the string variable zText contains text as follows:
+**
+**
+** char *zText = "It's a happy day!";
+**
+**
+** One can use this text in an SQL statement as follows:
+**
+**
+** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
+** sqlite3_exec(db, zSQL, 0, 0, 0);
+** sqlite3_free(zSQL);
+**
+**
+** Because the %q format string is used, the '\'' character in zText
+** is escaped and the SQL generated is as follows:
+**
+**
+** INSERT INTO table1 VALUES('It''s a happy day!')
+**
+**
+** This is correct. Had we used %s instead of %q, the generated SQL
+** would have looked like this:
+**
+**
+** INSERT INTO table1 VALUES('It's a happy day!');
+**
+**
+** This second example is an SQL syntax error. As a general rule you should
+** always use %q instead of %s when inserting text into a string literal.
+**
+** ^(The %Q option works like %q except it also adds single quotes around
+** the outside of the total string. Additionally, if the parameter in the
+** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
+** single quotes).)^ So, for example, one could say:
+**
+**
+** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
+** sqlite3_exec(db, zSQL, 0, 0, 0);
+** sqlite3_free(zSQL);
+**
+**
+** The code above will render a correct SQL statement in the zSQL
+** variable even if the zText variable is a NULL pointer.
+**
+** ^(The "%z" formatting option works like "%s" but with the
+** addition that after the string has been read and copied into
+** the result, [sqlite3_free()] is called on the input string.)^
+*/
+SQLITE_API char *sqlite3_mprintf(const char*,...);
+SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
+SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
+SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
+
+/*
+** CAPI3REF: Memory Allocation Subsystem
+**
+** The SQLite core uses these three routines for all of its own
+** internal memory allocation needs. "Core" in the previous sentence
+** does not include operating-system specific VFS implementation. The
+** Windows VFS uses native malloc() and free() for some operations.
+**
+** ^The sqlite3_malloc() routine returns a pointer to a block
+** of memory at least N bytes in length, where N is the parameter.
+** ^If sqlite3_malloc() is unable to obtain sufficient free
+** memory, it returns a NULL pointer. ^If the parameter N to
+** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
+** a NULL pointer.
+**
+** ^Calling sqlite3_free() with a pointer previously returned
+** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
+** that it might be reused. ^The sqlite3_free() routine is
+** a no-op if is called with a NULL pointer. Passing a NULL pointer
+** to sqlite3_free() is harmless. After being freed, memory
+** should neither be read nor written. Even reading previously freed
+** memory might result in a segmentation fault or other severe error.
+** Memory corruption, a segmentation fault, or other severe error
+** might result if sqlite3_free() is called with a non-NULL pointer that
+** was not obtained from sqlite3_malloc() or sqlite3_realloc().
+**
+** ^(The sqlite3_realloc() interface attempts to resize a
+** prior memory allocation to be at least N bytes, where N is the
+** second parameter. The memory allocation to be resized is the first
+** parameter.)^ ^ If the first parameter to sqlite3_realloc()
+** is a NULL pointer then its behavior is identical to calling
+** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
+** ^If the second parameter to sqlite3_realloc() is zero or
+** negative then the behavior is exactly the same as calling
+** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
+** ^sqlite3_realloc() returns a pointer to a memory allocation
+** of at least N bytes in size or NULL if sufficient memory is unavailable.
+** ^If M is the size of the prior allocation, then min(N,M) bytes
+** of the prior allocation are copied into the beginning of buffer returned
+** by sqlite3_realloc() and the prior allocation is freed.
+** ^If sqlite3_realloc() returns NULL, then the prior allocation
+** is not freed.
+**
+** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
+** is always aligned to at least an 8 byte boundary, or to a
+** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
+** option is used.
+**
+** In SQLite version 3.5.0 and 3.5.1, it was possible to define
+** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
+** implementation of these routines to be omitted. That capability
+** is no longer provided. Only built-in memory allocators can be used.
+**
+** Prior to SQLite version 3.7.10, the Windows OS interface layer called
+** the system malloc() and free() directly when converting
+** filenames between the UTF-8 encoding used by SQLite
+** and whatever filename encoding is used by the particular Windows
+** installation. Memory allocation errors were detected, but
+** they were reported back as [SQLITE_CANTOPEN] or
+** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
+**
+** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
+** must be either NULL or else pointers obtained from a prior
+** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
+** not yet been released.
+**
+** The application must not read or write any part of
+** a block of memory after it has been released using
+** [sqlite3_free()] or [sqlite3_realloc()].
+*/
+SQLITE_API void *sqlite3_malloc(int);
+SQLITE_API void *sqlite3_realloc(void*, int);
+SQLITE_API void sqlite3_free(void*);
+
+/*
+** CAPI3REF: Memory Allocator Statistics
+**
+** SQLite provides these two interfaces for reporting on the status
+** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
+** routines, which form the built-in memory allocation subsystem.
+**
+** ^The [sqlite3_memory_used()] routine returns the number of bytes
+** of memory currently outstanding (malloced but not freed).
+** ^The [sqlite3_memory_highwater()] routine returns the maximum
+** value of [sqlite3_memory_used()] since the high-water mark
+** was last reset. ^The values returned by [sqlite3_memory_used()] and
+** [sqlite3_memory_highwater()] include any overhead
+** added by SQLite in its implementation of [sqlite3_malloc()],
+** but not overhead added by the any underlying system library
+** routines that [sqlite3_malloc()] may call.
+**
+** ^The memory high-water mark is reset to the current value of
+** [sqlite3_memory_used()] if and only if the parameter to
+** [sqlite3_memory_highwater()] is true. ^The value returned
+** by [sqlite3_memory_highwater(1)] is the high-water mark
+** prior to the reset.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
+
+/*
+** CAPI3REF: Pseudo-Random Number Generator
+**
+** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
+** select random [ROWID | ROWIDs] when inserting new records into a table that
+** already uses the largest possible [ROWID]. The PRNG is also used for
+** the build-in random() and randomblob() SQL functions. This interface allows
+** applications to access the same PRNG for other purposes.
+**
+** ^A call to this routine stores N bytes of randomness into buffer P.
+** ^If N is less than one, then P can be a NULL pointer.
+**
+** ^If this routine has not been previously called or if the previous
+** call had N less than one, then the PRNG is seeded using randomness
+** obtained from the xRandomness method of the default [sqlite3_vfs] object.
+** ^If the previous call to this routine had an N of 1 or more then
+** the pseudo-randomness is generated
+** internally and without recourse to the [sqlite3_vfs] xRandomness
+** method.
+*/
+SQLITE_API void sqlite3_randomness(int N, void *P);
+
+/*
+** CAPI3REF: Compile-Time Authorization Callbacks
+**
+** ^This routine registers an authorizer callback with a particular
+** [database connection], supplied in the first argument.
+** ^The authorizer callback is invoked as SQL statements are being compiled
+** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
+** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
+** points during the compilation process, as logic is being created
+** to perform various actions, the authorizer callback is invoked to
+** see if those actions are allowed. ^The authorizer callback should
+** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
+** specific action but allow the SQL statement to continue to be
+** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
+** rejected with an error. ^If the authorizer callback returns
+** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
+** then the [sqlite3_prepare_v2()] or equivalent call that triggered
+** the authorizer will fail with an error message.
+**
+** When the callback returns [SQLITE_OK], that means the operation
+** requested is ok. ^When the callback returns [SQLITE_DENY], the
+** [sqlite3_prepare_v2()] or equivalent call that triggered the
+** authorizer will fail with an error message explaining that
+** access is denied.
+**
+** ^The first parameter to the authorizer callback is a copy of the third
+** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
+** to the callback is an integer [SQLITE_COPY | action code] that specifies
+** the particular action to be authorized. ^The third through sixth parameters
+** to the callback are zero-terminated strings that contain additional
+** details about the action to be authorized.
+**
+** ^If the action code is [SQLITE_READ]
+** and the callback returns [SQLITE_IGNORE] then the
+** [prepared statement] statement is constructed to substitute
+** a NULL value in place of the table column that would have
+** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
+** return can be used to deny an untrusted user access to individual
+** columns of a table.
+** ^If the action code is [SQLITE_DELETE] and the callback returns
+** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
+** [truncate optimization] is disabled and all rows are deleted individually.
+**
+** An authorizer is used when [sqlite3_prepare | preparing]
+** SQL statements from an untrusted source, to ensure that the SQL statements
+** do not try to access data they are not allowed to see, or that they do not
+** try to execute malicious statements that damage the database. For
+** example, an application may allow a user to enter arbitrary
+** SQL queries for evaluation by a database. But the application does
+** not want the user to be able to make arbitrary changes to the
+** database. An authorizer could then be put in place while the
+** user-entered SQL is being [sqlite3_prepare | prepared] that
+** disallows everything except [SELECT] statements.
+**
+** Applications that need to process SQL from untrusted sources
+** might also consider lowering resource limits using [sqlite3_limit()]
+** and limiting database size using the [max_page_count] [PRAGMA]
+** in addition to using an authorizer.
+**
+** ^(Only a single authorizer can be in place on a database connection
+** at a time. Each call to sqlite3_set_authorizer overrides the
+** previous call.)^ ^Disable the authorizer by installing a NULL callback.
+** The authorizer is disabled by default.
+**
+** The authorizer callback must not do anything that will modify
+** the database connection that invoked the authorizer callback.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
+** statement might be re-prepared during [sqlite3_step()] due to a
+** schema change. Hence, the application should ensure that the
+** correct authorizer callback remains in place during the [sqlite3_step()].
+**
+** ^Note that the authorizer callback is invoked only during
+** [sqlite3_prepare()] or its variants. Authorization is not
+** performed during statement evaluation in [sqlite3_step()], unless
+** as stated in the previous paragraph, sqlite3_step() invokes
+** sqlite3_prepare_v2() to reprepare a statement after a schema change.
+*/
+SQLITE_API int sqlite3_set_authorizer(
+ sqlite3*,
+ int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
+ void *pUserData
+);
+
+/*
+** CAPI3REF: Authorizer Return Codes
+**
+** The [sqlite3_set_authorizer | authorizer callback function] must
+** return either [SQLITE_OK] or one of these two constants in order
+** to signal SQLite whether or not the action is permitted. See the
+** [sqlite3_set_authorizer | authorizer documentation] for additional
+** information.
+**
+** Note that SQLITE_IGNORE is also used as a [SQLITE_ROLLBACK | return code]
+** from the [sqlite3_vtab_on_conflict()] interface.
+*/
+#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
+#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
+
+/*
+** CAPI3REF: Authorizer Action Codes
+**
+** The [sqlite3_set_authorizer()] interface registers a callback function
+** that is invoked to authorize certain SQL statement actions. The
+** second parameter to the callback is an integer code that specifies
+** what action is being authorized. These are the integer action codes that
+** the authorizer callback may be passed.
+**
+** These action code values signify what kind of operation is to be
+** authorized. The 3rd and 4th parameters to the authorization
+** callback function will be parameters or NULL depending on which of these
+** codes is used as the second parameter. ^(The 5th parameter to the
+** authorizer callback is the name of the database ("main", "temp",
+** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
+** is the name of the inner-most trigger or view that is responsible for
+** the access attempt or NULL if this access attempt is directly from
+** top-level SQL code.
+*/
+/******************************************* 3rd ************ 4th ***********/
+#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
+#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
+#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
+#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
+#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
+#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
+#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
+#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
+#define SQLITE_DELETE 9 /* Table Name NULL */
+#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
+#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
+#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
+#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
+#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
+#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
+#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
+#define SQLITE_DROP_VIEW 17 /* View Name NULL */
+#define SQLITE_INSERT 18 /* Table Name NULL */
+#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
+#define SQLITE_READ 20 /* Table Name Column Name */
+#define SQLITE_SELECT 21 /* NULL NULL */
+#define SQLITE_TRANSACTION 22 /* Operation NULL */
+#define SQLITE_UPDATE 23 /* Table Name Column Name */
+#define SQLITE_ATTACH 24 /* Filename NULL */
+#define SQLITE_DETACH 25 /* Database Name NULL */
+#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
+#define SQLITE_REINDEX 27 /* Index Name NULL */
+#define SQLITE_ANALYZE 28 /* Table Name NULL */
+#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
+#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
+#define SQLITE_FUNCTION 31 /* NULL Function Name */
+#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
+#define SQLITE_COPY 0 /* No longer used */
+#define SQLITE_RECURSIVE 33 /* NULL NULL */
+
+/*
+** CAPI3REF: Tracing And Profiling Functions
+**
+** These routines register callback functions that can be used for
+** tracing and profiling the execution of SQL statements.
+**
+** ^The callback function registered by sqlite3_trace() is invoked at
+** various times when an SQL statement is being run by [sqlite3_step()].
+** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
+** SQL statement text as the statement first begins executing.
+** ^(Additional sqlite3_trace() callbacks might occur
+** as each triggered subprogram is entered. The callbacks for triggers
+** contain a UTF-8 SQL comment that identifies the trigger.)^
+**
+** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
+** the length of [bound parameter] expansion in the output of sqlite3_trace().
+**
+** ^The callback function registered by sqlite3_profile() is invoked
+** as each SQL statement finishes. ^The profile callback contains
+** the original statement text and an estimate of wall-clock time
+** of how long that statement took to run. ^The profile callback
+** time is in units of nanoseconds, however the current implementation
+** is only capable of millisecond resolution so the six least significant
+** digits in the time are meaningless. Future versions of SQLite
+** might provide greater resolution on the profiler callback. The
+** sqlite3_profile() function is considered experimental and is
+** subject to change in future versions of SQLite.
+*/
+SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
+ void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
+
+/*
+** CAPI3REF: Query Progress Callbacks
+**
+** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
+** function X to be invoked periodically during long running calls to
+** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
+** database connection D. An example use for this
+** interface is to keep a GUI updated during a large query.
+**
+** ^The parameter P is passed through as the only parameter to the
+** callback function X. ^The parameter N is the approximate number of
+** [virtual machine instructions] that are evaluated between successive
+** invocations of the callback X. ^If N is less than one then the progress
+** handler is disabled.
+**
+** ^Only a single progress handler may be defined at one time per
+** [database connection]; setting a new progress handler cancels the
+** old one. ^Setting parameter X to NULL disables the progress handler.
+** ^The progress handler is also disabled by setting N to a value less
+** than 1.
+**
+** ^If the progress callback returns non-zero, the operation is
+** interrupted. This feature can be used to implement a
+** "Cancel" button on a GUI progress dialog box.
+**
+** The progress handler callback must not do anything that will modify
+** the database connection that invoked the progress handler.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+*/
+SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
+
+/*
+** CAPI3REF: Opening A New Database Connection
+**
+** ^These routines open an SQLite database file as specified by the
+** filename argument. ^The filename argument is interpreted as UTF-8 for
+** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
+** order for sqlite3_open16(). ^(A [database connection] handle is usually
+** returned in *ppDb, even if an error occurs. The only exception is that
+** if SQLite is unable to allocate memory to hold the [sqlite3] object,
+** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
+** object.)^ ^(If the database is opened (and/or created) successfully, then
+** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
+** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
+** an English language description of the error following a failure of any
+** of the sqlite3_open() routines.
+**
+** ^The default encoding for the database will be UTF-8 if
+** sqlite3_open() or sqlite3_open_v2() is called and
+** UTF-16 in the native byte order if sqlite3_open16() is used.
+**
+** Whether or not an error occurs when it is opened, resources
+** associated with the [database connection] handle should be released by
+** passing it to [sqlite3_close()] when it is no longer required.
+**
+** The sqlite3_open_v2() interface works like sqlite3_open()
+** except that it accepts two additional parameters for additional control
+** over the new database connection. ^(The flags parameter to
+** sqlite3_open_v2() can take one of
+** the following three values, optionally combined with the
+** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
+** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
+**
+**
+** ^(- [SQLITE_OPEN_READONLY]
+** - The database is opened in read-only mode. If the database does not
+** already exist, an error is returned.
)^
+**
+** ^(- [SQLITE_OPEN_READWRITE]
+** - The database is opened for reading and writing if possible, or reading
+** only if the file is write protected by the operating system. In either
+** case the database must already exist, otherwise an error is returned.
)^
+**
+** ^(- [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
+** - The database is opened for reading and writing, and is created if
+** it does not already exist. This is the behavior that is always used for
+** sqlite3_open() and sqlite3_open16().
)^
+**
+**
+** If the 3rd parameter to sqlite3_open_v2() is not one of the
+** combinations shown above optionally combined with other
+** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
+** then the behavior is undefined.
+**
+** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
+** opens in the multi-thread [threading mode] as long as the single-thread
+** mode has not been set at compile-time or start-time. ^If the
+** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
+** in the serialized [threading mode] unless single-thread was
+** previously selected at compile-time or start-time.
+** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
+** eligible to use [shared cache mode], regardless of whether or not shared
+** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
+** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
+** participate in [shared cache mode] even if it is enabled.
+**
+** ^The fourth parameter to sqlite3_open_v2() is the name of the
+** [sqlite3_vfs] object that defines the operating system interface that
+** the new database connection should use. ^If the fourth parameter is
+** a NULL pointer then the default [sqlite3_vfs] object is used.
+**
+** ^If the filename is ":memory:", then a private, temporary in-memory database
+** is created for the connection. ^This in-memory database will vanish when
+** the database connection is closed. Future versions of SQLite might
+** make use of additional special filenames that begin with the ":" character.
+** It is recommended that when a database filename actually does begin with
+** a ":" character you should prefix the filename with a pathname such as
+** "./" to avoid ambiguity.
+**
+** ^If the filename is an empty string, then a private, temporary
+** on-disk database will be created. ^This private database will be
+** automatically deleted as soon as the database connection is closed.
+**
+** [[URI filenames in sqlite3_open()]] URI Filenames
+**
+** ^If [URI filename] interpretation is enabled, and the filename argument
+** begins with "file:", then the filename is interpreted as a URI. ^URI
+** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
+** set in the fourth argument to sqlite3_open_v2(), or if it has
+** been enabled globally using the [SQLITE_CONFIG_URI] option with the
+** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
+** As of SQLite version 3.7.7, URI filename interpretation is turned off
+** by default, but future releases of SQLite might enable URI filename
+** interpretation by default. See "[URI filenames]" for additional
+** information.
+**
+** URI filenames are parsed according to RFC 3986. ^If the URI contains an
+** authority, then it must be either an empty string or the string
+** "localhost". ^If the authority is not an empty string or "localhost", an
+** error is returned to the caller. ^The fragment component of a URI, if
+** present, is ignored.
+**
+** ^SQLite uses the path component of the URI as the name of the disk file
+** which contains the database. ^If the path begins with a '/' character,
+** then it is interpreted as an absolute path. ^If the path does not begin
+** with a '/' (meaning that the authority section is omitted from the URI)
+** then the path is interpreted as a relative path.
+** ^On windows, the first component of an absolute path
+** is a drive specification (e.g. "C:").
+**
+** [[core URI query parameters]]
+** The query component of a URI may contain parameters that are interpreted
+** either by SQLite itself, or by a [VFS | custom VFS implementation].
+** SQLite interprets the following three query parameters:
+**
+**
+** - vfs: ^The "vfs" parameter may be used to specify the name of
+** a VFS object that provides the operating system interface that should
+** be used to access the database file on disk. ^If this option is set to
+** an empty string the default VFS object is used. ^Specifying an unknown
+** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
+** present, then the VFS specified by the option takes precedence over
+** the value passed as the fourth parameter to sqlite3_open_v2().
+**
+**
- mode: ^(The mode parameter may be set to either "ro", "rw",
+** "rwc", or "memory". Attempting to set it to any other value is
+** an error)^.
+** ^If "ro" is specified, then the database is opened for read-only
+** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
+** third argument to sqlite3_open_v2(). ^If the mode option is set to
+** "rw", then the database is opened for read-write (but not create)
+** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
+** been set. ^Value "rwc" is equivalent to setting both
+** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
+** set to "memory" then a pure [in-memory database] that never reads
+** or writes from disk is used. ^It is an error to specify a value for
+** the mode parameter that is less restrictive than that specified by
+** the flags passed in the third parameter to sqlite3_open_v2().
+**
+**
- cache: ^The cache parameter may be set to either "shared" or
+** "private". ^Setting it to "shared" is equivalent to setting the
+** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
+** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
+** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
+** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
+** a URI filename, its value overrides any behavior requested by setting
+** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
+**
+**
- psow: ^The psow parameter may be "true" (or "on" or "yes" or
+** "1") or "false" (or "off" or "no" or "0") to indicate that the
+** [powersafe overwrite] property does or does not apply to the
+** storage media on which the database file resides. ^The psow query
+** parameter only works for the built-in unix and Windows VFSes.
+**
+**
- nolock: ^The nolock parameter is a boolean query parameter
+** which if set disables file locking in rollback journal modes. This
+** is useful for accessing a database on a filesystem that does not
+** support locking. Caution: Database corruption might result if two
+** or more processes write to the same database and any one of those
+** processes uses nolock=1.
+**
+**
- immutable: ^The immutable parameter is a boolean query
+** parameter that indicates that the database file is stored on
+** read-only media. ^When immutable is set, SQLite assumes that the
+** database file cannot be changed, even by a process with higher
+** privilege, and so the database is opened read-only and all locking
+** and change detection is disabled. Caution: Setting the immutable
+** property on a database file that does in fact change can result
+** in incorrect query results and/or [SQLITE_CORRUPT] errors.
+** See also: [SQLITE_IOCAP_IMMUTABLE].
+**
+**
+**
+** ^Specifying an unknown parameter in the query component of a URI is not an
+** error. Future versions of SQLite might understand additional query
+** parameters. See "[query parameters with special meaning to SQLite]" for
+** additional information.
+**
+** [[URI filename examples]] URI filename examples
+**
+**
+** URI filenames | Results
+** |
---|
file:data.db |
+** Open the file "data.db" in the current directory.
+** |
file:/home/fred/data.db
+** file:///home/fred/data.db
+** file://localhost/home/fred/data.db |
+** Open the database file "/home/fred/data.db".
+** |
file://darkstar/home/fred/data.db |
+** An error. "darkstar" is not a recognized authority.
+** |
+** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
+** | Windows only: Open the file "data.db" on fred's desktop on drive
+** C:. Note that the %20 escaping in this example is not strictly
+** necessary - space characters can be used literally
+** in URI filenames.
+** |
file:data.db?mode=ro&cache=private |
+** Open file "data.db" in the current directory for read-only access.
+** Regardless of whether or not shared-cache mode is enabled by
+** default, use a private cache.
+** |
file:/home/fred/data.db?vfs=unix-dotfile |
+** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
+** that uses dot-files in place of posix advisory locking.
+** |
file:data.db?mode=readonly |
+** An error. "readonly" is not a valid option for the "mode" parameter.
+** |
+**
+** ^URI hexadecimal escape sequences (%HH) are supported within the path and
+** query components of a URI. A hexadecimal escape sequence consists of a
+** percent sign - "%" - followed by exactly two hexadecimal digits
+** specifying an octet value. ^Before the path or query components of a
+** URI filename are interpreted, they are encoded using UTF-8 and all
+** hexadecimal escape sequences replaced by a single byte containing the
+** corresponding octet. If this process generates an invalid UTF-8 encoding,
+** the results are undefined.
+**
+** Note to Windows users: The encoding used for the filename argument
+** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
+** codepage is currently defined. Filenames containing international
+** characters must be converted to UTF-8 prior to passing them into
+** sqlite3_open() or sqlite3_open_v2().
+**
+** Note to Windows Runtime users: The temporary directory must be set
+** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
+** features that require the use of temporary files may fail.
+**
+** See also: [sqlite3_temp_directory]
+*/
+SQLITE_API int sqlite3_open(
+ const char *filename, /* Database filename (UTF-8) */
+ sqlite3 **ppDb /* OUT: SQLite db handle */
+);
+SQLITE_API int sqlite3_open16(
+ const void *filename, /* Database filename (UTF-16) */
+ sqlite3 **ppDb /* OUT: SQLite db handle */
+);
+SQLITE_API int sqlite3_open_v2(
+ const char *filename, /* Database filename (UTF-8) */
+ sqlite3 **ppDb, /* OUT: SQLite db handle */
+ int flags, /* Flags */
+ const char *zVfs /* Name of VFS module to use */
+);
+
+/*
+** CAPI3REF: Obtain Values For URI Parameters
+**
+** These are utility routines, useful to VFS implementations, that check
+** to see if a database file was a URI that contained a specific query
+** parameter, and if so obtains the value of that query parameter.
+**
+** If F is the database filename pointer passed into the xOpen() method of
+** a VFS implementation when the flags parameter to xOpen() has one or
+** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
+** P is the name of the query parameter, then
+** sqlite3_uri_parameter(F,P) returns the value of the P
+** parameter if it exists or a NULL pointer if P does not appear as a
+** query parameter on F. If P is a query parameter of F
+** has no explicit value, then sqlite3_uri_parameter(F,P) returns
+** a pointer to an empty string.
+**
+** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
+** parameter and returns true (1) or false (0) according to the value
+** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
+** value of query parameter P is one of "yes", "true", or "on" in any
+** case or if the value begins with a non-zero number. The
+** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
+** query parameter P is one of "no", "false", or "off" in any case or
+** if the value begins with a numeric zero. If P is not a query
+** parameter on F or if the value of P is does not match any of the
+** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
+**
+** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
+** 64-bit signed integer and returns that integer, or D if P does not
+** exist. If the value of P is something other than an integer, then
+** zero is returned.
+**
+** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
+** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
+** is not a database file pathname pointer that SQLite passed into the xOpen
+** VFS method, then the behavior of this routine is undefined and probably
+** undesirable.
+*/
+SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
+SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
+SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
+
+
+/*
+** CAPI3REF: Error Codes And Messages
+**
+** ^The sqlite3_errcode() interface returns the numeric [result code] or
+** [extended result code] for the most recent failed sqlite3_* API call
+** associated with a [database connection]. If a prior API call failed
+** but the most recent API call succeeded, the return value from
+** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
+** interface is the same except that it always returns the
+** [extended result code] even when extended result codes are
+** disabled.
+**
+** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
+** text that describes the error, as either UTF-8 or UTF-16 respectively.
+** ^(Memory to hold the error message string is managed internally.
+** The application does not need to worry about freeing the result.
+** However, the error string might be overwritten or deallocated by
+** subsequent calls to other SQLite interface functions.)^
+**
+** ^The sqlite3_errstr() interface returns the English-language text
+** that describes the [result code], as UTF-8.
+** ^(Memory to hold the error message string is managed internally
+** and must not be freed by the application)^.
+**
+** When the serialized [threading mode] is in use, it might be the
+** case that a second error occurs on a separate thread in between
+** the time of the first error and the call to these interfaces.
+** When that happens, the second error will be reported since these
+** interfaces always report the most recent result. To avoid
+** this, each thread can obtain exclusive use of the [database connection] D
+** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
+** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
+** all calls to the interfaces listed here are completed.
+**
+** If an interface fails with SQLITE_MISUSE, that means the interface
+** was invoked incorrectly by the application. In that case, the
+** error code and message may or may not be set.
+*/
+SQLITE_API int sqlite3_errcode(sqlite3 *db);
+SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
+SQLITE_API const char *sqlite3_errmsg(sqlite3*);
+SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
+SQLITE_API const char *sqlite3_errstr(int);
+
+/*
+** CAPI3REF: SQL Statement Object
+** KEYWORDS: {prepared statement} {prepared statements}
+**
+** An instance of this object represents a single SQL statement.
+** This object is variously known as a "prepared statement" or a
+** "compiled SQL statement" or simply as a "statement".
+**
+** The life of a statement object goes something like this:
+**
+**
+** - Create the object using [sqlite3_prepare_v2()] or a related
+** function.
+**
- Bind values to [host parameters] using the sqlite3_bind_*()
+** interfaces.
+**
- Run the SQL by calling [sqlite3_step()] one or more times.
+**
- Reset the statement using [sqlite3_reset()] then go back
+** to step 2. Do this zero or more times.
+**
- Destroy the object using [sqlite3_finalize()].
+**
+**
+** Refer to documentation on individual methods above for additional
+** information.
+*/
+typedef struct sqlite3_stmt sqlite3_stmt;
+
+/*
+** CAPI3REF: Run-time Limits
+**
+** ^(This interface allows the size of various constructs to be limited
+** on a connection by connection basis. The first parameter is the
+** [database connection] whose limit is to be set or queried. The
+** second parameter is one of the [limit categories] that define a
+** class of constructs to be size limited. The third parameter is the
+** new limit for that construct.)^
+**
+** ^If the new limit is a negative number, the limit is unchanged.
+** ^(For each limit category SQLITE_LIMIT_NAME there is a
+** [limits | hard upper bound]
+** set at compile-time by a C preprocessor macro called
+** [limits | SQLITE_MAX_NAME].
+** (The "_LIMIT_" in the name is changed to "_MAX_".))^
+** ^Attempts to increase a limit above its hard upper bound are
+** silently truncated to the hard upper bound.
+**
+** ^Regardless of whether or not the limit was changed, the
+** [sqlite3_limit()] interface returns the prior value of the limit.
+** ^Hence, to find the current value of a limit without changing it,
+** simply invoke this interface with the third parameter set to -1.
+**
+** Run-time limits are intended for use in applications that manage
+** both their own internal database and also databases that are controlled
+** by untrusted external sources. An example application might be a
+** web browser that has its own databases for storing history and
+** separate databases controlled by JavaScript applications downloaded
+** off the Internet. The internal databases can be given the
+** large, default limits. Databases managed by external sources can
+** be given much smaller limits designed to prevent a denial of service
+** attack. Developers might also want to use the [sqlite3_set_authorizer()]
+** interface to further control untrusted SQL. The size of the database
+** created by an untrusted script can be contained using the
+** [max_page_count] [PRAGMA].
+**
+** New run-time limit categories may be added in future releases.
+*/
+SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
+
+/*
+** CAPI3REF: Run-Time Limit Categories
+** KEYWORDS: {limit category} {*limit categories}
+**
+** These constants define various performance limits
+** that can be lowered at run-time using [sqlite3_limit()].
+** The synopsis of the meanings of the various limits is shown below.
+** Additional information is available at [limits | Limits in SQLite].
+**
+**
+** [[SQLITE_LIMIT_LENGTH]] ^(- SQLITE_LIMIT_LENGTH
+** - The maximum size of any string or BLOB or table row, in bytes.
- )^
+**
+** [[SQLITE_LIMIT_SQL_LENGTH]] ^(
- SQLITE_LIMIT_SQL_LENGTH
+** - The maximum length of an SQL statement, in bytes.
)^
+**
+** [[SQLITE_LIMIT_COLUMN]] ^(- SQLITE_LIMIT_COLUMN
+** - The maximum number of columns in a table definition or in the
+** result set of a [SELECT] or the maximum number of columns in an index
+** or in an ORDER BY or GROUP BY clause.
)^
+**
+** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(- SQLITE_LIMIT_EXPR_DEPTH
+** - The maximum depth of the parse tree on any expression.
)^
+**
+** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(- SQLITE_LIMIT_COMPOUND_SELECT
+** - The maximum number of terms in a compound SELECT statement.
)^
+**
+** [[SQLITE_LIMIT_VDBE_OP]] ^(- SQLITE_LIMIT_VDBE_OP
+** - The maximum number of instructions in a virtual machine program
+** used to implement an SQL statement. This limit is not currently
+** enforced, though that might be added in some future release of
+** SQLite.
)^
+**
+** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(- SQLITE_LIMIT_FUNCTION_ARG
+** - The maximum number of arguments on a function.
)^
+**
+** [[SQLITE_LIMIT_ATTACHED]] ^(- SQLITE_LIMIT_ATTACHED
+** - The maximum number of [ATTACH | attached databases].)^
+**
+** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
+** ^(- SQLITE_LIMIT_LIKE_PATTERN_LENGTH
+** - The maximum length of the pattern argument to the [LIKE] or
+** [GLOB] operators.
)^
+**
+** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
+** ^(- SQLITE_LIMIT_VARIABLE_NUMBER
+** - The maximum index number of any [parameter] in an SQL statement.)^
+**
+** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(
- SQLITE_LIMIT_TRIGGER_DEPTH
+** - The maximum depth of recursion for triggers.
)^
+**
+*/
+#define SQLITE_LIMIT_LENGTH 0
+#define SQLITE_LIMIT_SQL_LENGTH 1
+#define SQLITE_LIMIT_COLUMN 2
+#define SQLITE_LIMIT_EXPR_DEPTH 3
+#define SQLITE_LIMIT_COMPOUND_SELECT 4
+#define SQLITE_LIMIT_VDBE_OP 5
+#define SQLITE_LIMIT_FUNCTION_ARG 6
+#define SQLITE_LIMIT_ATTACHED 7
+#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
+#define SQLITE_LIMIT_VARIABLE_NUMBER 9
+#define SQLITE_LIMIT_TRIGGER_DEPTH 10
+
+/*
+** CAPI3REF: Compiling An SQL Statement
+** KEYWORDS: {SQL statement compiler}
+**
+** To execute an SQL query, it must first be compiled into a byte-code
+** program using one of these routines.
+**
+** The first argument, "db", is a [database connection] obtained from a
+** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
+** [sqlite3_open16()]. The database connection must not have been closed.
+**
+** The second argument, "zSql", is the statement to be compiled, encoded
+** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
+** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
+** use UTF-16.
+**
+** ^If the nByte argument is less than zero, then zSql is read up to the
+** first zero terminator. ^If nByte is non-negative, then it is the maximum
+** number of bytes read from zSql. ^When nByte is non-negative, the
+** zSql string ends at either the first '\000' or '\u0000' character or
+** the nByte-th byte, whichever comes first. If the caller knows
+** that the supplied string is nul-terminated, then there is a small
+** performance advantage to be gained by passing an nByte parameter that
+** is equal to the number of bytes in the input string including
+** the nul-terminator bytes as this saves SQLite from having to
+** make a copy of the input string.
+**
+** ^If pzTail is not NULL then *pzTail is made to point to the first byte
+** past the end of the first SQL statement in zSql. These routines only
+** compile the first statement in zSql, so *pzTail is left pointing to
+** what remains uncompiled.
+**
+** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
+** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
+** to NULL. ^If the input text contains no SQL (if the input is an empty
+** string or a comment) then *ppStmt is set to NULL.
+** The calling procedure is responsible for deleting the compiled
+** SQL statement using [sqlite3_finalize()] after it has finished with it.
+** ppStmt may not be NULL.
+**
+** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
+** otherwise an [error code] is returned.
+**
+** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
+** recommended for all new programs. The two older interfaces are retained
+** for backwards compatibility, but their use is discouraged.
+** ^In the "v2" interfaces, the prepared statement
+** that is returned (the [sqlite3_stmt] object) contains a copy of the
+** original SQL text. This causes the [sqlite3_step()] interface to
+** behave differently in three ways:
+**
+**
+** -
+** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
+** always used to do, [sqlite3_step()] will automatically recompile the SQL
+** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
+** retries will occur before sqlite3_step() gives up and returns an error.
+**
+**
+** -
+** ^When an error occurs, [sqlite3_step()] will return one of the detailed
+** [error codes] or [extended error codes]. ^The legacy behavior was that
+** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
+** and the application would have to make a second call to [sqlite3_reset()]
+** in order to find the underlying cause of the problem. With the "v2" prepare
+** interfaces, the underlying reason for the error is returned immediately.
+**
+**
+** -
+** ^If the specific value bound to [parameter | host parameter] in the
+** WHERE clause might influence the choice of query plan for a statement,
+** then the statement will be automatically recompiled, as if there had been
+** a schema change, on the first [sqlite3_step()] call following any change
+** to the [sqlite3_bind_text | bindings] of that [parameter].
+** ^The specific value of WHERE-clause [parameter] might influence the
+** choice of query plan if the parameter is the left-hand side of a [LIKE]
+** or [GLOB] operator or if the parameter is compared to an indexed column
+** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
+**
+**
+*/
+SQLITE_API int sqlite3_prepare(
+ sqlite3 *db, /* Database handle */
+ const char *zSql, /* SQL statement, UTF-8 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const char **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare_v2(
+ sqlite3 *db, /* Database handle */
+ const char *zSql, /* SQL statement, UTF-8 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const char **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare16(
+ sqlite3 *db, /* Database handle */
+ const void *zSql, /* SQL statement, UTF-16 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const void **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare16_v2(
+ sqlite3 *db, /* Database handle */
+ const void *zSql, /* SQL statement, UTF-16 encoded */
+ int nByte, /* Maximum length of zSql in bytes. */
+ sqlite3_stmt **ppStmt, /* OUT: Statement handle */
+ const void **pzTail /* OUT: Pointer to unused portion of zSql */
+);
+
+/*
+** CAPI3REF: Retrieving Statement SQL
+**
+** ^This interface can be used to retrieve a saved copy of the original
+** SQL text used to create a [prepared statement] if that statement was
+** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
+*/
+SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Determine If An SQL Statement Writes The Database
+**
+** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
+** and only if the [prepared statement] X makes no direct changes to
+** the content of the database file.
+**
+** Note that [application-defined SQL functions] or
+** [virtual tables] might change the database indirectly as a side effect.
+** ^(For example, if an application defines a function "eval()" that
+** calls [sqlite3_exec()], then the following SQL statement would
+** change the database file through side-effects:
+**
+**
+** SELECT eval('DELETE FROM t1') FROM t2;
+**
+**
+** But because the [SELECT] statement does not change the database file
+** directly, sqlite3_stmt_readonly() would still return true.)^
+**
+** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
+** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
+** since the statements themselves do not actually modify the database but
+** rather they control the timing of when other statements modify the
+** database. ^The [ATTACH] and [DETACH] statements also cause
+** sqlite3_stmt_readonly() to return true since, while those statements
+** change the configuration of a database connection, they do not make
+** changes to the content of the database files on disk.
+*/
+SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Determine If A Prepared Statement Has Been Reset
+**
+** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
+** [prepared statement] S has been stepped at least once using
+** [sqlite3_step(S)] but has not run to completion and/or has not
+** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
+** interface returns false if S is a NULL pointer. If S is not a
+** NULL pointer and is not a pointer to a valid [prepared statement]
+** object, then the behavior is undefined and probably undesirable.
+**
+** This interface can be used in combination [sqlite3_next_stmt()]
+** to locate all prepared statements associated with a database
+** connection that are in need of being reset. This can be used,
+** for example, in diagnostic routines to search for prepared
+** statements that are holding a transaction open.
+*/
+SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Dynamically Typed Value Object
+** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
+**
+** SQLite uses the sqlite3_value object to represent all values
+** that can be stored in a database table. SQLite uses dynamic typing
+** for the values it stores. ^Values stored in sqlite3_value objects
+** can be integers, floating point values, strings, BLOBs, or NULL.
+**
+** An sqlite3_value object may be either "protected" or "unprotected".
+** Some interfaces require a protected sqlite3_value. Other interfaces
+** will accept either a protected or an unprotected sqlite3_value.
+** Every interface that accepts sqlite3_value arguments specifies
+** whether or not it requires a protected sqlite3_value.
+**
+** The terms "protected" and "unprotected" refer to whether or not
+** a mutex is held. An internal mutex is held for a protected
+** sqlite3_value object but no mutex is held for an unprotected
+** sqlite3_value object. If SQLite is compiled to be single-threaded
+** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
+** or if SQLite is run in one of reduced mutex modes
+** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
+** then there is no distinction between protected and unprotected
+** sqlite3_value objects and they can be used interchangeably. However,
+** for maximum code portability it is recommended that applications
+** still make the distinction between protected and unprotected
+** sqlite3_value objects even when not strictly required.
+**
+** ^The sqlite3_value objects that are passed as parameters into the
+** implementation of [application-defined SQL functions] are protected.
+** ^The sqlite3_value object returned by
+** [sqlite3_column_value()] is unprotected.
+** Unprotected sqlite3_value objects may only be used with
+** [sqlite3_result_value()] and [sqlite3_bind_value()].
+** The [sqlite3_value_blob | sqlite3_value_type()] family of
+** interfaces require protected sqlite3_value objects.
+*/
+typedef struct Mem sqlite3_value;
+
+/*
+** CAPI3REF: SQL Function Context Object
+**
+** The context in which an SQL function executes is stored in an
+** sqlite3_context object. ^A pointer to an sqlite3_context object
+** is always first parameter to [application-defined SQL functions].
+** The application-defined SQL function implementation will pass this
+** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
+** [sqlite3_aggregate_context()], [sqlite3_user_data()],
+** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
+** and/or [sqlite3_set_auxdata()].
+*/
+typedef struct sqlite3_context sqlite3_context;
+
+/*
+** CAPI3REF: Binding Values To Prepared Statements
+** KEYWORDS: {host parameter} {host parameters} {host parameter name}
+** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
+**
+** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
+** literals may be replaced by a [parameter] that matches one of following
+** templates:
+**
+**
+** - ?
+**
- ?NNN
+**
- :VVV
+**
- @VVV
+**
- $VVV
+**
+**
+** In the templates above, NNN represents an integer literal,
+** and VVV represents an alphanumeric identifier.)^ ^The values of these
+** parameters (also called "host parameter names" or "SQL parameters")
+** can be set using the sqlite3_bind_*() routines defined here.
+**
+** ^The first argument to the sqlite3_bind_*() routines is always
+** a pointer to the [sqlite3_stmt] object returned from
+** [sqlite3_prepare_v2()] or its variants.
+**
+** ^The second argument is the index of the SQL parameter to be set.
+** ^The leftmost SQL parameter has an index of 1. ^When the same named
+** SQL parameter is used more than once, second and subsequent
+** occurrences have the same index as the first occurrence.
+** ^The index for named parameters can be looked up using the
+** [sqlite3_bind_parameter_index()] API if desired. ^The index
+** for "?NNN" parameters is the value of NNN.
+** ^The NNN value must be between 1 and the [sqlite3_limit()]
+** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
+**
+** ^The third argument is the value to bind to the parameter.
+** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
+** is ignored and the end result is the same as sqlite3_bind_null().
+**
+** ^(In those routines that have a fourth argument, its value is the
+** number of bytes in the parameter. To be clear: the value is the
+** number of bytes in the value, not the number of characters.)^
+** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** is negative, then the length of the string is
+** the number of bytes up to the first zero terminator.
+** If the fourth parameter to sqlite3_bind_blob() is negative, then
+** the behavior is undefined.
+** If a non-negative fourth parameter is provided to sqlite3_bind_text()
+** or sqlite3_bind_text16() then that parameter must be the byte offset
+** where the NUL terminator would occur assuming the string were NUL
+** terminated. If any NUL characters occur at byte offsets less than
+** the value of the fourth parameter then the resulting string value will
+** contain embedded NULs. The result of expressions involving strings
+** with embedded NULs is undefined.
+**
+** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
+** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
+** string after SQLite has finished with it. ^The destructor is called
+** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
+** sqlite3_bind_text(), or sqlite3_bind_text16() fails.
+** ^If the fifth argument is
+** the special value [SQLITE_STATIC], then SQLite assumes that the
+** information is in static, unmanaged space and does not need to be freed.
+** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
+** SQLite makes its own private copy of the data immediately, before
+** the sqlite3_bind_*() routine returns.
+**
+** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
+** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
+** (just an integer to hold its size) while it is being processed.
+** Zeroblobs are intended to serve as placeholders for BLOBs whose
+** content is later written using
+** [sqlite3_blob_open | incremental BLOB I/O] routines.
+** ^A negative value for the zeroblob results in a zero-length BLOB.
+**
+** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
+** for the [prepared statement] or with a prepared statement for which
+** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
+** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
+** routine is passed a [prepared statement] that has been finalized, the
+** result is undefined and probably harmful.
+**
+** ^Bindings are not cleared by the [sqlite3_reset()] routine.
+** ^Unbound parameters are interpreted as NULL.
+**
+** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
+** [error code] if anything goes wrong.
+** ^[SQLITE_RANGE] is returned if the parameter
+** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
+**
+** See also: [sqlite3_bind_parameter_count()],
+** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
+SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
+SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
+SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
+SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
+SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
+SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
+SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
+SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
+
+/*
+** CAPI3REF: Number Of SQL Parameters
+**
+** ^This routine can be used to find the number of [SQL parameters]
+** in a [prepared statement]. SQL parameters are tokens of the
+** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
+** placeholders for values that are [sqlite3_bind_blob | bound]
+** to the parameters at a later time.
+**
+** ^(This routine actually returns the index of the largest (rightmost)
+** parameter. For all forms except ?NNN, this will correspond to the
+** number of unique parameters. If parameters of the ?NNN form are used,
+** there may be gaps in the list.)^
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_name()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Name Of A Host Parameter
+**
+** ^The sqlite3_bind_parameter_name(P,N) interface returns
+** the name of the N-th [SQL parameter] in the [prepared statement] P.
+** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** respectively.
+** In other words, the initial ":" or "$" or "@" or "?"
+** is included as part of the name.)^
+** ^Parameters of the form "?" without a following integer have no name
+** and are referred to as "nameless" or "anonymous parameters".
+**
+** ^The first host parameter has an index of 1, not 0.
+**
+** ^If the value N is out of range or if the N-th parameter is
+** nameless, then NULL is returned. ^The returned string is
+** always in UTF-8 encoding even if the named parameter was
+** originally specified as UTF-16 in [sqlite3_prepare16()] or
+** [sqlite3_prepare16_v2()].
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_count()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
+
+/*
+** CAPI3REF: Index Of A Parameter With A Given Name
+**
+** ^Return the index of an SQL parameter given its name. ^The
+** index value returned is suitable for use as the second
+** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
+** is returned if no matching parameter is found. ^The parameter
+** name must be given in UTF-8 even if the original statement
+** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_count()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
+
+/*
+** CAPI3REF: Reset All Bindings On A Prepared Statement
+**
+** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
+** the [sqlite3_bind_blob | bindings] on a [prepared statement].
+** ^Use this routine to reset all host parameters to NULL.
+*/
+SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Number Of Columns In A Result Set
+**
+** ^Return the number of columns in the result set returned by the
+** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
+** statement that does not return data (for example an [UPDATE]).
+**
+** See also: [sqlite3_data_count()]
+*/
+SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Column Names In A Result Set
+**
+** ^These routines return the name assigned to a particular column
+** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
+** interface returns a pointer to a zero-terminated UTF-8 string
+** and sqlite3_column_name16() returns a pointer to a zero-terminated
+** UTF-16 string. ^The first parameter is the [prepared statement]
+** that implements the [SELECT] statement. ^The second parameter is the
+** column number. ^The leftmost column is number 0.
+**
+** ^The returned string pointer is valid until either the [prepared statement]
+** is destroyed by [sqlite3_finalize()] or until the statement is automatically
+** reprepared by the first call to [sqlite3_step()] for a particular run
+** or until the next call to
+** sqlite3_column_name() or sqlite3_column_name16() on the same column.
+**
+** ^If sqlite3_malloc() fails during the processing of either routine
+** (for example during a conversion from UTF-8 to UTF-16) then a
+** NULL pointer is returned.
+**
+** ^The name of a result column is the value of the "AS" clause for
+** that column, if there is an AS clause. If there is no AS clause
+** then the name of the column is unspecified and may change from
+** one release of SQLite to the next.
+*/
+SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
+SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
+
+/*
+** CAPI3REF: Source Of Data In A Query Result
+**
+** ^These routines provide a means to determine the database, table, and
+** table column that is the origin of a particular result column in
+** [SELECT] statement.
+** ^The name of the database or table or column can be returned as
+** either a UTF-8 or UTF-16 string. ^The _database_ routines return
+** the database name, the _table_ routines return the table name, and
+** the origin_ routines return the column name.
+** ^The returned string is valid until the [prepared statement] is destroyed
+** using [sqlite3_finalize()] or until the statement is automatically
+** reprepared by the first call to [sqlite3_step()] for a particular run
+** or until the same information is requested
+** again in a different encoding.
+**
+** ^The names returned are the original un-aliased names of the
+** database, table, and column.
+**
+** ^The first argument to these interfaces is a [prepared statement].
+** ^These functions return information about the Nth result column returned by
+** the statement, where N is the second function argument.
+** ^The left-most column is column 0 for these routines.
+**
+** ^If the Nth column returned by the statement is an expression or
+** subquery and is not a column value, then all of these functions return
+** NULL. ^These routine might also return NULL if a memory allocation error
+** occurs. ^Otherwise, they return the name of the attached database, table,
+** or column that query result column was extracted from.
+**
+** ^As with all other SQLite APIs, those whose names end with "16" return
+** UTF-16 encoded strings and the other functions return UTF-8.
+**
+** ^These APIs are only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
+**
+** If two or more threads call one or more of these routines against the same
+** prepared statement and column at the same time then the results are
+** undefined.
+**
+** If two or more threads call one or more
+** [sqlite3_column_database_name | column metadata interfaces]
+** for the same [prepared statement] and result column
+** at the same time then the results are undefined.
+*/
+SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Declared Datatype Of A Query Result
+**
+** ^(The first parameter is a [prepared statement].
+** If this statement is a [SELECT] statement and the Nth column of the
+** returned result set of that [SELECT] is a table column (not an
+** expression or subquery) then the declared type of the table
+** column is returned.)^ ^If the Nth column of the result set is an
+** expression or subquery, then a NULL pointer is returned.
+** ^The returned string is always UTF-8 encoded.
+**
+** ^(For example, given the database schema:
+**
+** CREATE TABLE t1(c1 VARIANT);
+**
+** and the following statement to be compiled:
+**
+** SELECT c1 + 1, c1 FROM t1;
+**
+** this routine would return the string "VARIANT" for the second result
+** column (i==1), and a NULL pointer for the first result column (i==0).)^
+**
+** ^SQLite uses dynamic run-time typing. ^So just because a column
+** is declared to contain a particular type does not mean that the
+** data stored in that column is of the declared type. SQLite is
+** strongly typed, but the typing is dynamic not static. ^Type
+** is associated with individual values, not with the containers
+** used to hold those values.
+*/
+SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Evaluate An SQL Statement
+**
+** After a [prepared statement] has been prepared using either
+** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
+** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
+** must be called one or more times to evaluate the statement.
+**
+** The details of the behavior of the sqlite3_step() interface depend
+** on whether the statement was prepared using the newer "v2" interface
+** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
+** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
+** new "v2" interface is recommended for new applications but the legacy
+** interface will continue to be supported.
+**
+** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
+** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
+** ^With the "v2" interface, any of the other [result codes] or
+** [extended result codes] might be returned as well.
+**
+** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
+** database locks it needs to do its job. ^If the statement is a [COMMIT]
+** or occurs outside of an explicit transaction, then you can retry the
+** statement. If the statement is not a [COMMIT] and occurs within an
+** explicit transaction then you should rollback the transaction before
+** continuing.
+**
+** ^[SQLITE_DONE] means that the statement has finished executing
+** successfully. sqlite3_step() should not be called again on this virtual
+** machine without first calling [sqlite3_reset()] to reset the virtual
+** machine back to its initial state.
+**
+** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
+** is returned each time a new row of data is ready for processing by the
+** caller. The values may be accessed using the [column access functions].
+** sqlite3_step() is called again to retrieve the next row of data.
+**
+** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
+** violation) has occurred. sqlite3_step() should not be called again on
+** the VM. More information may be found by calling [sqlite3_errmsg()].
+** ^With the legacy interface, a more specific error code (for example,
+** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
+** can be obtained by calling [sqlite3_reset()] on the
+** [prepared statement]. ^In the "v2" interface,
+** the more specific error code is returned directly by sqlite3_step().
+**
+** [SQLITE_MISUSE] means that the this routine was called inappropriately.
+** Perhaps it was called on a [prepared statement] that has
+** already been [sqlite3_finalize | finalized] or on one that had
+** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
+** be the case that the same database connection is being used by two or
+** more threads at the same moment in time.
+**
+** For all versions of SQLite up to and including 3.6.23.1, a call to
+** [sqlite3_reset()] was required after sqlite3_step() returned anything
+** other than [SQLITE_ROW] before any subsequent invocation of
+** sqlite3_step(). Failure to reset the prepared statement using
+** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
+** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began
+** calling [sqlite3_reset()] automatically in this circumstance rather
+** than returning [SQLITE_MISUSE]. This is not considered a compatibility
+** break because any application that ever receives an SQLITE_MISUSE error
+** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
+** can be used to restore the legacy behavior.
+**
+** Goofy Interface Alert: In the legacy interface, the sqlite3_step()
+** API always returns a generic error code, [SQLITE_ERROR], following any
+** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
+** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
+** specific [error codes] that better describes the error.
+** We admit that this is a goofy design. The problem has been fixed
+** with the "v2" interface. If you prepare all of your SQL statements
+** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
+** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
+** then the more specific [error codes] are returned directly
+** by sqlite3_step(). The use of the "v2" interface is recommended.
+*/
+SQLITE_API int sqlite3_step(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Number of columns in a result set
+**
+** ^The sqlite3_data_count(P) interface returns the number of columns in the
+** current row of the result set of [prepared statement] P.
+** ^If prepared statement P does not have results ready to return
+** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
+** interfaces) then sqlite3_data_count(P) returns 0.
+** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
+** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
+** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
+** will return non-zero if previous call to [sqlite3_step](P) returned
+** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
+** where it always returns zero since each step of that multi-step
+** pragma returns 0 columns of data.
+**
+** See also: [sqlite3_column_count()]
+*/
+SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Fundamental Datatypes
+** KEYWORDS: SQLITE_TEXT
+**
+** ^(Every value in SQLite has one of five fundamental datatypes:
+**
+**
+** - 64-bit signed integer
+**
- 64-bit IEEE floating point number
+**
- string
+**
- BLOB
+**
- NULL
+**
)^
+**
+** These constants are codes for each of those types.
+**
+** Note that the SQLITE_TEXT constant was also used in SQLite version 2
+** for a completely different meaning. Software that links against both
+** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
+** SQLITE_TEXT.
+*/
+#define SQLITE_INTEGER 1
+#define SQLITE_FLOAT 2
+#define SQLITE_BLOB 4
+#define SQLITE_NULL 5
+#ifdef SQLITE_TEXT
+# undef SQLITE_TEXT
+#else
+# define SQLITE_TEXT 3
+#endif
+#define SQLITE3_TEXT 3
+
+/*
+** CAPI3REF: Result Values From A Query
+** KEYWORDS: {column access functions}
+**
+** These routines form the "result set" interface.
+**
+** ^These routines return information about a single column of the current
+** result row of a query. ^In every case the first argument is a pointer
+** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
+** that was returned from [sqlite3_prepare_v2()] or one of its variants)
+** and the second argument is the index of the column for which information
+** should be returned. ^The leftmost column of the result set has the index 0.
+** ^The number of columns in the result can be determined using
+** [sqlite3_column_count()].
+**
+** If the SQL statement does not currently point to a valid row, or if the
+** column index is out of range, the result is undefined.
+** These routines may only be called when the most recent call to
+** [sqlite3_step()] has returned [SQLITE_ROW] and neither
+** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
+** If any of these routines are called after [sqlite3_reset()] or
+** [sqlite3_finalize()] or after [sqlite3_step()] has returned
+** something other than [SQLITE_ROW], the results are undefined.
+** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
+** are called from a different thread while any of these routines
+** are pending, then the results are undefined.
+**
+** ^The sqlite3_column_type() routine returns the
+** [SQLITE_INTEGER | datatype code] for the initial data type
+** of the result column. ^The returned value is one of [SQLITE_INTEGER],
+** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
+** returned by sqlite3_column_type() is only meaningful if no type
+** conversions have occurred as described below. After a type conversion,
+** the value returned by sqlite3_column_type() is undefined. Future
+** versions of SQLite may change the behavior of sqlite3_column_type()
+** following a type conversion.
+**
+** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
+** the string to UTF-8 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
+**
+** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
+** the string to UTF-16 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes16() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
+**
+** ^The values returned by [sqlite3_column_bytes()] and
+** [sqlite3_column_bytes16()] do not include the zero terminators at the end
+** of the string. ^For clarity: the values returned by
+** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
+** bytes in the string, not the number of characters.
+**
+** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
+** even empty strings, are always zero-terminated. ^The return
+** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
+**
+** ^The object returned by [sqlite3_column_value()] is an
+** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
+** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
+** If the [unprotected sqlite3_value] object returned by
+** [sqlite3_column_value()] is used in any other way, including calls
+** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
+** or [sqlite3_value_bytes()], then the behavior is undefined.
+**
+** These routines attempt to convert the value where appropriate. ^For
+** example, if the internal representation is FLOAT and a text result
+** is requested, [sqlite3_snprintf()] is used internally to perform the
+** conversion automatically. ^(The following table details the conversions
+** that are applied:
+**
+**
+**
+** Internal Type | Requested Type | Conversion
+**
+** |
---|
NULL | INTEGER | Result is 0
+** |
NULL | FLOAT | Result is 0.0
+** |
NULL | TEXT | Result is a NULL pointer
+** |
NULL | BLOB | Result is a NULL pointer
+** |
INTEGER | FLOAT | Convert from integer to float
+** |
INTEGER | TEXT | ASCII rendering of the integer
+** |
INTEGER | BLOB | Same as INTEGER->TEXT
+** |
FLOAT | INTEGER | [CAST] to INTEGER
+** |
FLOAT | TEXT | ASCII rendering of the float
+** |
FLOAT | BLOB | [CAST] to BLOB
+** |
TEXT | INTEGER | [CAST] to INTEGER
+** |
TEXT | FLOAT | [CAST] to REAL
+** |
TEXT | BLOB | No change
+** |
BLOB | INTEGER | [CAST] to INTEGER
+** |
BLOB | FLOAT | [CAST] to REAL
+** |
BLOB | TEXT | Add a zero terminator if needed
+** |
+**
)^
+**
+** The table above makes reference to standard C library functions atoi()
+** and atof(). SQLite does not really use these functions. It has its
+** own equivalent internal routines. The atoi() and atof() names are
+** used in the table for brevity and because they are familiar to most
+** C programmers.
+**
+** Note that when type conversions occur, pointers returned by prior
+** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
+** sqlite3_column_text16() may be invalidated.
+** Type conversions and pointer invalidations might occur
+** in the following cases:
+**
+**
+** - The initial content is a BLOB and sqlite3_column_text() or
+** sqlite3_column_text16() is called. A zero-terminator might
+** need to be added to the string.
+** - The initial content is UTF-8 text and sqlite3_column_bytes16() or
+** sqlite3_column_text16() is called. The content must be converted
+** to UTF-16.
+** - The initial content is UTF-16 text and sqlite3_column_bytes() or
+** sqlite3_column_text() is called. The content must be converted
+** to UTF-8.
+**
+**
+** ^Conversions between UTF-16be and UTF-16le are always done in place and do
+** not invalidate a prior pointer, though of course the content of the buffer
+** that the prior pointer references will have been modified. Other kinds
+** of conversion are done in place when it is possible, but sometimes they
+** are not possible and in those cases prior pointers are invalidated.
+**
+** The safest and easiest to remember policy is to invoke these routines
+** in one of the following ways:
+**
+**
+** - sqlite3_column_text() followed by sqlite3_column_bytes()
+** - sqlite3_column_blob() followed by sqlite3_column_bytes()
+** - sqlite3_column_text16() followed by sqlite3_column_bytes16()
+**
+**
+** In other words, you should call sqlite3_column_text(),
+** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
+** into the desired format, then invoke sqlite3_column_bytes() or
+** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
+** to sqlite3_column_text() or sqlite3_column_blob() with calls to
+** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
+** with calls to sqlite3_column_bytes().
+**
+** ^The pointers returned are valid until a type conversion occurs as
+** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
+** [sqlite3_finalize()] is called. ^The memory space used to hold strings
+** and BLOBs is freed automatically. Do not pass the pointers returned
+** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
+** [sqlite3_free()].
+**
+** ^(If a memory allocation error occurs during the evaluation of any
+** of these routines, a default value is returned. The default value
+** is either the integer 0, the floating point number 0.0, or a NULL
+** pointer. Subsequent calls to [sqlite3_errcode()] will return
+** [SQLITE_NOMEM].)^
+*/
+SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
+SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
+SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
+SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
+
+/*
+** CAPI3REF: Destroy A Prepared Statement Object
+**
+** ^The sqlite3_finalize() function is called to delete a [prepared statement].
+** ^If the most recent evaluation of the statement encountered no errors
+** or if the statement is never been evaluated, then sqlite3_finalize() returns
+** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
+** sqlite3_finalize(S) returns the appropriate [error code] or
+** [extended error code].
+**
+** ^The sqlite3_finalize(S) routine can be called at any point during
+** the life cycle of [prepared statement] S:
+** before statement S is ever evaluated, after
+** one or more calls to [sqlite3_reset()], or after any call
+** to [sqlite3_step()] regardless of whether or not the statement has
+** completed execution.
+**
+** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
+**
+** The application must finalize every [prepared statement] in order to avoid
+** resource leaks. It is a grievous error for the application to try to use
+** a prepared statement after it has been finalized. Any use of a prepared
+** statement after it has been finalized can result in undefined and
+** undesirable behavior such as segfaults and heap corruption.
+*/
+SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Reset A Prepared Statement Object
+**
+** The sqlite3_reset() function is called to reset a [prepared statement]
+** object back to its initial state, ready to be re-executed.
+** ^Any SQL statement variables that had values bound to them using
+** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
+** Use [sqlite3_clear_bindings()] to reset the bindings.
+**
+** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
+** back to the beginning of its program.
+**
+** ^If the most recent call to [sqlite3_step(S)] for the
+** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
+** or if [sqlite3_step(S)] has never before been called on S,
+** then [sqlite3_reset(S)] returns [SQLITE_OK].
+**
+** ^If the most recent call to [sqlite3_step(S)] for the
+** [prepared statement] S indicated an error, then
+** [sqlite3_reset(S)] returns an appropriate [error code].
+**
+** ^The [sqlite3_reset(S)] interface does not change the values
+** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
+*/
+SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Create Or Redefine SQL Functions
+** KEYWORDS: {function creation routines}
+** KEYWORDS: {application-defined SQL function}
+** KEYWORDS: {application-defined SQL functions}
+**
+** ^These functions (collectively known as "function creation routines")
+** are used to add SQL functions or aggregates or to redefine the behavior
+** of existing SQL functions or aggregates. The only differences between
+** these routines are the text encoding expected for
+** the second parameter (the name of the function being created)
+** and the presence or absence of a destructor callback for
+** the application data pointer.
+**
+** ^The first parameter is the [database connection] to which the SQL
+** function is to be added. ^If an application uses more than one database
+** connection then application-defined SQL functions must be added
+** to each database connection separately.
+**
+** ^The second parameter is the name of the SQL function to be created or
+** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
+** representation, exclusive of the zero-terminator. ^Note that the name
+** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
+** ^Any attempt to create a function with a longer name
+** will result in [SQLITE_MISUSE] being returned.
+**
+** ^The third parameter (nArg)
+** is the number of arguments that the SQL function or
+** aggregate takes. ^If this parameter is -1, then the SQL function or
+** aggregate may take any number of arguments between 0 and the limit
+** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
+** parameter is less than -1 or greater than 127 then the behavior is
+** undefined.
+**
+** ^The fourth parameter, eTextRep, specifies what
+** [SQLITE_UTF8 | text encoding] this SQL function prefers for
+** its parameters. The application should set this parameter to
+** [SQLITE_UTF16LE] if the function implementation invokes
+** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
+** implementation invokes [sqlite3_value_text16be()] on an input, or
+** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
+** otherwise. ^The same SQL function may be registered multiple times using
+** different preferred text encodings, with different implementations for
+** each encoding.
+** ^When multiple implementations of the same function are available, SQLite
+** will pick the one that involves the least amount of data conversion.
+**
+** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
+** to signal that the function will always return the same result given
+** the same inputs within a single SQL statement. Most SQL functions are
+** deterministic. The built-in [random()] SQL function is an example of a
+** function that is not deterministic. The SQLite query planner is able to
+** perform additional optimizations on deterministic functions, so use
+** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
+**
+** ^(The fifth parameter is an arbitrary pointer. The implementation of the
+** function can gain access to this pointer using [sqlite3_user_data()].)^
+**
+** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
+** pointers to C-language functions that implement the SQL function or
+** aggregate. ^A scalar SQL function requires an implementation of the xFunc
+** callback only; NULL pointers must be passed as the xStep and xFinal
+** parameters. ^An aggregate SQL function requires an implementation of xStep
+** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
+** SQL function or aggregate, pass NULL pointers for all three function
+** callbacks.
+**
+** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
+** then it is destructor for the application data pointer.
+** The destructor is invoked when the function is deleted, either by being
+** overloaded or when the database connection closes.)^
+** ^The destructor is also invoked if the call to
+** sqlite3_create_function_v2() fails.
+** ^When the destructor callback of the tenth parameter is invoked, it
+** is passed a single argument which is a copy of the application data
+** pointer which was the fifth parameter to sqlite3_create_function_v2().
+**
+** ^It is permitted to register multiple implementations of the same
+** functions with the same name but with either differing numbers of
+** arguments or differing preferred text encodings. ^SQLite will use
+** the implementation that most closely matches the way in which the
+** SQL function is used. ^A function implementation with a non-negative
+** nArg parameter is a better match than a function implementation with
+** a negative nArg. ^A function where the preferred text encoding
+** matches the database encoding is a better
+** match than a function where the encoding is different.
+** ^A function where the encoding difference is between UTF16le and UTF16be
+** is a closer match than a function where the encoding difference is
+** between UTF8 and UTF16.
+**
+** ^Built-in functions may be overloaded by new application-defined functions.
+**
+** ^An application-defined function is permitted to call other
+** SQLite interfaces. However, such calls must not
+** close the database connection nor finalize or reset the prepared
+** statement in which the function is running.
+*/
+SQLITE_API int sqlite3_create_function(
+ sqlite3 *db,
+ const char *zFunctionName,
+ int nArg,
+ int eTextRep,
+ void *pApp,
+ void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+ void (*xFinal)(sqlite3_context*)
+);
+SQLITE_API int sqlite3_create_function16(
+ sqlite3 *db,
+ const void *zFunctionName,
+ int nArg,
+ int eTextRep,
+ void *pApp,
+ void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+ void (*xFinal)(sqlite3_context*)
+);
+SQLITE_API int sqlite3_create_function_v2(
+ sqlite3 *db,
+ const char *zFunctionName,
+ int nArg,
+ int eTextRep,
+ void *pApp,
+ void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+ void (*xFinal)(sqlite3_context*),
+ void(*xDestroy)(void*)
+);
+
+/*
+** CAPI3REF: Text Encodings
+**
+** These constant define integer codes that represent the various
+** text encodings supported by SQLite.
+*/
+#define SQLITE_UTF8 1
+#define SQLITE_UTF16LE 2
+#define SQLITE_UTF16BE 3
+#define SQLITE_UTF16 4 /* Use native byte order */
+#define SQLITE_ANY 5 /* Deprecated */
+#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
+
+/*
+** CAPI3REF: Function Flags
+**
+** These constants may be ORed together with the
+** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
+** to [sqlite3_create_function()], [sqlite3_create_function16()], or
+** [sqlite3_create_function_v2()].
+*/
+#define SQLITE_DETERMINISTIC 0x800
+
+/*
+** CAPI3REF: Deprecated Functions
+** DEPRECATED
+**
+** These functions are [deprecated]. In order to maintain
+** backwards compatibility with older code, these functions continue
+** to be supported. However, new applications should avoid
+** the use of these functions. To help encourage people to avoid
+** using these functions, we are not going to tell you what they do.
+*/
+#ifndef SQLITE_OMIT_DEPRECATED
+SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
+SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
+ void*,sqlite3_int64);
+#endif
+
+/*
+** CAPI3REF: Obtaining SQL Function Parameter Values
+**
+** The C-language implementation of SQL functions and aggregates uses
+** this set of interface routines to access the parameter values on
+** the function or aggregate.
+**
+** The xFunc (for scalar functions) or xStep (for aggregates) parameters
+** to [sqlite3_create_function()] and [sqlite3_create_function16()]
+** define callbacks that implement the SQL functions and aggregates.
+** The 3rd parameter to these callbacks is an array of pointers to
+** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
+** each parameter to the SQL function. These routines are used to
+** extract values from the [sqlite3_value] objects.
+**
+** These routines work only with [protected sqlite3_value] objects.
+** Any attempt to use these routines on an [unprotected sqlite3_value]
+** object results in undefined behavior.
+**
+** ^These routines work just like the corresponding [column access functions]
+** except that these routines take a single [protected sqlite3_value] object
+** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
+**
+** ^The sqlite3_value_text16() interface extracts a UTF-16 string
+** in the native byte-order of the host machine. ^The
+** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
+** extract UTF-16 strings as big-endian and little-endian respectively.
+**
+** ^(The sqlite3_value_numeric_type() interface attempts to apply
+** numeric affinity to the value. This means that an attempt is
+** made to convert the value to an integer or floating point. If
+** such a conversion is possible without loss of information (in other
+** words, if the value is a string that looks like a number)
+** then the conversion is performed. Otherwise no conversion occurs.
+** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
+**
+** Please pay particular attention to the fact that the pointer returned
+** from [sqlite3_value_blob()], [sqlite3_value_text()], or
+** [sqlite3_value_text16()] can be invalidated by a subsequent call to
+** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
+** or [sqlite3_value_text16()].
+**
+** These routines must be called from the same thread as
+** the SQL function that supplied the [sqlite3_value*] parameters.
+*/
+SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
+SQLITE_API double sqlite3_value_double(sqlite3_value*);
+SQLITE_API int sqlite3_value_int(sqlite3_value*);
+SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
+SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
+SQLITE_API int sqlite3_value_type(sqlite3_value*);
+SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
+
+/*
+** CAPI3REF: Obtain Aggregate Function Context
+**
+** Implementations of aggregate SQL functions use this
+** routine to allocate memory for storing their state.
+**
+** ^The first time the sqlite3_aggregate_context(C,N) routine is called
+** for a particular aggregate function, SQLite
+** allocates N of memory, zeroes out that memory, and returns a pointer
+** to the new memory. ^On second and subsequent calls to
+** sqlite3_aggregate_context() for the same aggregate function instance,
+** the same buffer is returned. Sqlite3_aggregate_context() is normally
+** called once for each invocation of the xStep callback and then one
+** last time when the xFinal callback is invoked. ^(When no rows match
+** an aggregate query, the xStep() callback of the aggregate function
+** implementation is never called and xFinal() is called exactly once.
+** In those cases, sqlite3_aggregate_context() might be called for the
+** first time from within xFinal().)^
+**
+** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
+** when first called if N is less than or equal to zero or if a memory
+** allocate error occurs.
+**
+** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
+** determined by the N parameter on first successful call. Changing the
+** value of N in subsequent call to sqlite3_aggregate_context() within
+** the same aggregate function instance will not resize the memory
+** allocation.)^ Within the xFinal callback, it is customary to set
+** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
+** pointless memory allocations occur.
+**
+** ^SQLite automatically frees the memory allocated by
+** sqlite3_aggregate_context() when the aggregate query concludes.
+**
+** The first parameter must be a copy of the
+** [sqlite3_context | SQL function context] that is the first parameter
+** to the xStep or xFinal callback routine that implements the aggregate
+** function.
+**
+** This routine must be called from the same thread in which
+** the aggregate SQL function is running.
+*/
+SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
+
+/*
+** CAPI3REF: User Data For Functions
+**
+** ^The sqlite3_user_data() interface returns a copy of
+** the pointer that was the pUserData parameter (the 5th parameter)
+** of the [sqlite3_create_function()]
+** and [sqlite3_create_function16()] routines that originally
+** registered the application defined function.
+**
+** This routine must be called from the same thread in which
+** the application-defined function is running.
+*/
+SQLITE_API void *sqlite3_user_data(sqlite3_context*);
+
+/*
+** CAPI3REF: Database Connection For Functions
+**
+** ^The sqlite3_context_db_handle() interface returns a copy of
+** the pointer to the [database connection] (the 1st parameter)
+** of the [sqlite3_create_function()]
+** and [sqlite3_create_function16()] routines that originally
+** registered the application defined function.
+*/
+SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
+
+/*
+** CAPI3REF: Function Auxiliary Data
+**
+** These functions may be used by (non-aggregate) SQL functions to
+** associate metadata with argument values. If the same value is passed to
+** multiple invocations of the same SQL function during query execution, under
+** some circumstances the associated metadata may be preserved. An example
+** of where this might be useful is in a regular-expression matching
+** function. The compiled version of the regular expression can be stored as
+** metadata associated with the pattern string.
+** Then as long as the pattern string remains the same,
+** the compiled regular expression can be reused on multiple
+** invocations of the same function.
+**
+** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
+** associated by the sqlite3_set_auxdata() function with the Nth argument
+** value to the application-defined function. ^If there is no metadata
+** associated with the function argument, this sqlite3_get_auxdata() interface
+** returns a NULL pointer.
+**
+** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
+** argument of the application-defined function. ^Subsequent
+** calls to sqlite3_get_auxdata(C,N) return P from the most recent
+** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
+** NULL if the metadata has been discarded.
+** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
+** SQLite will invoke the destructor function X with parameter P exactly
+** once, when the metadata is discarded.
+** SQLite is free to discard the metadata at any time, including:
+** - when the corresponding function parameter changes, or
+**
- when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
+** SQL statement, or
+**
- when sqlite3_set_auxdata() is invoked again on the same parameter, or
+**
- during the original sqlite3_set_auxdata() call when a memory
+** allocation error occurs.
)^
+**
+** Note the last bullet in particular. The destructor X in
+** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
+** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
+** should be called near the end of the function implementation and the
+** function implementation should not make any use of P after
+** sqlite3_set_auxdata() has been called.
+**
+** ^(In practice, metadata is preserved between function calls for
+** function parameters that are compile-time constants, including literal
+** values and [parameters] and expressions composed from the same.)^
+**
+** These routines must be called from the same thread in which
+** the SQL function is running.
+*/
+SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
+SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
+
+
+/*
+** CAPI3REF: Constants Defining Special Destructor Behavior
+**
+** These are special values for the destructor that is passed in as the
+** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
+** argument is SQLITE_STATIC, it means that the content pointer is constant
+** and will never change. It does not need to be destroyed. ^The
+** SQLITE_TRANSIENT value means that the content will likely change in
+** the near future and that SQLite should make its own private copy of
+** the content before returning.
+**
+** The typedef is necessary to work around problems in certain
+** C++ compilers.
+*/
+typedef void (*sqlite3_destructor_type)(void*);
+#define SQLITE_STATIC ((sqlite3_destructor_type)0)
+#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
+
+/*
+** CAPI3REF: Setting The Result Of An SQL Function
+**
+** These routines are used by the xFunc or xFinal callbacks that
+** implement SQL functions and aggregates. See
+** [sqlite3_create_function()] and [sqlite3_create_function16()]
+** for additional information.
+**
+** These functions work very much like the [parameter binding] family of
+** functions used to bind values to host parameters in prepared statements.
+** Refer to the [SQL parameter] documentation for additional information.
+**
+** ^The sqlite3_result_blob() interface sets the result from
+** an application-defined function to be the BLOB whose content is pointed
+** to by the second parameter and which is N bytes long where N is the
+** third parameter.
+**
+** ^The sqlite3_result_zeroblob() interfaces set the result of
+** the application-defined function to be a BLOB containing all zero
+** bytes and N bytes in size, where N is the value of the 2nd parameter.
+**
+** ^The sqlite3_result_double() interface sets the result from
+** an application-defined function to be a floating point value specified
+** by its 2nd argument.
+**
+** ^The sqlite3_result_error() and sqlite3_result_error16() functions
+** cause the implemented SQL function to throw an exception.
+** ^SQLite uses the string pointed to by the
+** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
+** as the text of an error message. ^SQLite interprets the error
+** message string from sqlite3_result_error() as UTF-8. ^SQLite
+** interprets the string from sqlite3_result_error16() as UTF-16 in native
+** byte order. ^If the third parameter to sqlite3_result_error()
+** or sqlite3_result_error16() is negative then SQLite takes as the error
+** message all text up through the first zero character.
+** ^If the third parameter to sqlite3_result_error() or
+** sqlite3_result_error16() is non-negative then SQLite takes that many
+** bytes (not characters) from the 2nd parameter as the error message.
+** ^The sqlite3_result_error() and sqlite3_result_error16()
+** routines make a private copy of the error message text before
+** they return. Hence, the calling function can deallocate or
+** modify the text after they return without harm.
+** ^The sqlite3_result_error_code() function changes the error code
+** returned by SQLite as a result of an error in a function. ^By default,
+** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
+** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
+**
+** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
+** error indicating that a string or BLOB is too long to represent.
+**
+** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
+** error indicating that a memory allocation failed.
+**
+** ^The sqlite3_result_int() interface sets the return value
+** of the application-defined function to be the 32-bit signed integer
+** value given in the 2nd argument.
+** ^The sqlite3_result_int64() interface sets the return value
+** of the application-defined function to be the 64-bit signed integer
+** value given in the 2nd argument.
+**
+** ^The sqlite3_result_null() interface sets the return value
+** of the application-defined function to be NULL.
+**
+** ^The sqlite3_result_text(), sqlite3_result_text16(),
+** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
+** set the return value of the application-defined function to be
+** a text string which is represented as UTF-8, UTF-16 native byte order,
+** UTF-16 little endian, or UTF-16 big endian, respectively.
+** ^SQLite takes the text result from the application from
+** the 2nd parameter of the sqlite3_result_text* interfaces.
+** ^If the 3rd parameter to the sqlite3_result_text* interfaces
+** is negative, then SQLite takes result text from the 2nd parameter
+** through the first zero character.
+** ^If the 3rd parameter to the sqlite3_result_text* interfaces
+** is non-negative, then as many bytes (not characters) of the text
+** pointed to by the 2nd parameter are taken as the application-defined
+** function result. If the 3rd parameter is non-negative, then it
+** must be the byte offset into the string where the NUL terminator would
+** appear if the string where NUL terminated. If any NUL characters occur
+** in the string at a byte offset that is less than the value of the 3rd
+** parameter, then the resulting string will contain embedded NULs and the
+** result of expressions operating on strings with embedded NULs is undefined.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces
+** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
+** function as the destructor on the text or BLOB result when it has
+** finished using that result.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
+** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
+** assumes that the text or BLOB result is in constant space and does not
+** copy the content of the parameter nor call a destructor on the content
+** when it has finished using that result.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces
+** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
+** then SQLite makes a copy of the result into space obtained from
+** from [sqlite3_malloc()] before it returns.
+**
+** ^The sqlite3_result_value() interface sets the result of
+** the application-defined function to be a copy the
+** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
+** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
+** so that the [sqlite3_value] specified in the parameter may change or
+** be deallocated after sqlite3_result_value() returns without harm.
+** ^A [protected sqlite3_value] object may always be used where an
+** [unprotected sqlite3_value] object is required, so either
+** kind of [sqlite3_value] object can be used with this interface.
+**
+** If these routines are called from within the different thread
+** than the one containing the application-defined function that received
+** the [sqlite3_context] pointer, the results are undefined.
+*/
+SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
+SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
+SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
+SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
+SQLITE_API void sqlite3_result_null(sqlite3_context*);
+SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
+SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
+
+/*
+** CAPI3REF: Define New Collating Sequences
+**
+** ^These functions add, remove, or modify a [collation] associated
+** with the [database connection] specified as the first argument.
+**
+** ^The name of the collation is a UTF-8 string
+** for sqlite3_create_collation() and sqlite3_create_collation_v2()
+** and a UTF-16 string in native byte order for sqlite3_create_collation16().
+** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
+** considered to be the same name.
+**
+** ^(The third argument (eTextRep) must be one of the constants:
+**
+** - [SQLITE_UTF8],
+**
- [SQLITE_UTF16LE],
+**
- [SQLITE_UTF16BE],
+**
- [SQLITE_UTF16], or
+**
- [SQLITE_UTF16_ALIGNED].
+**
)^
+** ^The eTextRep argument determines the encoding of strings passed
+** to the collating function callback, xCallback.
+** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
+** force strings to be UTF16 with native byte order.
+** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
+** on an even byte address.
+**
+** ^The fourth argument, pArg, is an application data pointer that is passed
+** through as the first argument to the collating function callback.
+**
+** ^The fifth argument, xCallback, is a pointer to the collating function.
+** ^Multiple collating functions can be registered using the same name but
+** with different eTextRep parameters and SQLite will use whichever
+** function requires the least amount of data transformation.
+** ^If the xCallback argument is NULL then the collating function is
+** deleted. ^When all collating functions having the same name are deleted,
+** that collation is no longer usable.
+**
+** ^The collating function callback is invoked with a copy of the pArg
+** application data pointer and with two strings in the encoding specified
+** by the eTextRep argument. The collating function must return an
+** integer that is negative, zero, or positive
+** if the first string is less than, equal to, or greater than the second,
+** respectively. A collating function must always return the same answer
+** given the same inputs. If two or more collating functions are registered
+** to the same collation name (using different eTextRep values) then all
+** must give an equivalent answer when invoked with equivalent strings.
+** The collating function must obey the following properties for all
+** strings A, B, and C:
+**
+**
+** - If A==B then B==A.
+**
- If A==B and B==C then A==C.
+**
- If A<B THEN B>A.
+**
- If A<B and B<C then A<C.
+**
+**
+** If a collating function fails any of the above constraints and that
+** collating function is registered and used, then the behavior of SQLite
+** is undefined.
+**
+** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
+** with the addition that the xDestroy callback is invoked on pArg when
+** the collating function is deleted.
+** ^Collating functions are deleted when they are overridden by later
+** calls to the collation creation functions or when the
+** [database connection] is closed using [sqlite3_close()].
+**
+** ^The xDestroy callback is not called if the
+** sqlite3_create_collation_v2() function fails. Applications that invoke
+** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
+** check the return code and dispose of the application data pointer
+** themselves rather than expecting SQLite to deal with it for them.
+** This is different from every other SQLite interface. The inconsistency
+** is unfortunate but cannot be changed without breaking backwards
+** compatibility.
+**
+** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
+*/
+SQLITE_API int sqlite3_create_collation(
+ sqlite3*,
+ const char *zName,
+ int eTextRep,
+ void *pArg,
+ int(*xCompare)(void*,int,const void*,int,const void*)
+);
+SQLITE_API int sqlite3_create_collation_v2(
+ sqlite3*,
+ const char *zName,
+ int eTextRep,
+ void *pArg,
+ int(*xCompare)(void*,int,const void*,int,const void*),
+ void(*xDestroy)(void*)
+);
+SQLITE_API int sqlite3_create_collation16(
+ sqlite3*,
+ const void *zName,
+ int eTextRep,
+ void *pArg,
+ int(*xCompare)(void*,int,const void*,int,const void*)
+);
+
+/*
+** CAPI3REF: Collation Needed Callbacks
+**
+** ^To avoid having to register all collation sequences before a database
+** can be used, a single callback function may be registered with the
+** [database connection] to be invoked whenever an undefined collation
+** sequence is required.
+**
+** ^If the function is registered using the sqlite3_collation_needed() API,
+** then it is passed the names of undefined collation sequences as strings
+** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
+** the names are passed as UTF-16 in machine native byte order.
+** ^A call to either function replaces the existing collation-needed callback.
+**
+** ^(When the callback is invoked, the first argument passed is a copy
+** of the second argument to sqlite3_collation_needed() or
+** sqlite3_collation_needed16(). The second argument is the database
+** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
+** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
+** sequence function required. The fourth parameter is the name of the
+** required collation sequence.)^
+**
+** The callback function should register the desired collation using
+** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
+** [sqlite3_create_collation_v2()].
+*/
+SQLITE_API int sqlite3_collation_needed(
+ sqlite3*,
+ void*,
+ void(*)(void*,sqlite3*,int eTextRep,const char*)
+);
+SQLITE_API int sqlite3_collation_needed16(
+ sqlite3*,
+ void*,
+ void(*)(void*,sqlite3*,int eTextRep,const void*)
+);
+
+#ifdef SQLITE_HAS_CODEC
+/*
+** Specify the key for an encrypted database. This routine should be
+** called right after sqlite3_open().
+**
+** The code to implement this API is not available in the public release
+** of SQLite.
+*/
+SQLITE_API int sqlite3_key(
+ sqlite3 *db, /* Database to be rekeyed */
+ const void *pKey, int nKey /* The key */
+);
+SQLITE_API int sqlite3_key_v2(
+ sqlite3 *db, /* Database to be rekeyed */
+ const char *zDbName, /* Name of the database */
+ const void *pKey, int nKey /* The key */
+);
+
+/*
+** Change the key on an open database. If the current database is not
+** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
+** database is decrypted.
+**
+** The code to implement this API is not available in the public release
+** of SQLite.
+*/
+SQLITE_API int sqlite3_rekey(
+ sqlite3 *db, /* Database to be rekeyed */
+ const void *pKey, int nKey /* The new key */
+);
+SQLITE_API int sqlite3_rekey_v2(
+ sqlite3 *db, /* Database to be rekeyed */
+ const char *zDbName, /* Name of the database */
+ const void *pKey, int nKey /* The new key */
+);
+
+/*
+** Specify the activation key for a SEE database. Unless
+** activated, none of the SEE routines will work.
+*/
+SQLITE_API void sqlite3_activate_see(
+ const char *zPassPhrase /* Activation phrase */
+);
+#endif
+
+#ifdef SQLITE_ENABLE_CEROD
+/*
+** Specify the activation key for a CEROD database. Unless
+** activated, none of the CEROD routines will work.
+*/
+SQLITE_API void sqlite3_activate_cerod(
+ const char *zPassPhrase /* Activation phrase */
+);
+#endif
+
+/*
+** CAPI3REF: Suspend Execution For A Short Time
+**
+** The sqlite3_sleep() function causes the current thread to suspend execution
+** for at least a number of milliseconds specified in its parameter.
+**
+** If the operating system does not support sleep requests with
+** millisecond time resolution, then the time will be rounded up to
+** the nearest second. The number of milliseconds of sleep actually
+** requested from the operating system is returned.
+**
+** ^SQLite implements this interface by calling the xSleep()
+** method of the default [sqlite3_vfs] object. If the xSleep() method
+** of the default VFS is not implemented correctly, or not implemented at
+** all, then the behavior of sqlite3_sleep() may deviate from the description
+** in the previous paragraphs.
+*/
+SQLITE_API int sqlite3_sleep(int);
+
+/*
+** CAPI3REF: Name Of The Folder Holding Temporary Files
+**
+** ^(If this global variable is made to point to a string which is
+** the name of a folder (a.k.a. directory), then all temporary files
+** created by SQLite when using a built-in [sqlite3_vfs | VFS]
+** will be placed in that directory.)^ ^If this variable
+** is a NULL pointer, then SQLite performs a search for an appropriate
+** temporary file directory.
+**
+** It is not safe to read or modify this variable in more than one
+** thread at a time. It is not safe to read or modify this variable
+** if a [database connection] is being used at the same time in a separate
+** thread.
+** It is intended that this variable be set once
+** as part of process initialization and before any SQLite interface
+** routines have been called and that this variable remain unchanged
+** thereafter.
+**
+** ^The [temp_store_directory pragma] may modify this variable and cause
+** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
+** the [temp_store_directory pragma] always assumes that any string
+** that this variable points to is held in memory obtained from
+** [sqlite3_malloc] and the pragma may attempt to free that memory
+** using [sqlite3_free].
+** Hence, if this variable is modified directly, either it should be
+** made NULL or made to point to memory obtained from [sqlite3_malloc]
+** or else the use of the [temp_store_directory pragma] should be avoided.
+**
+** Note to Windows Runtime users: The temporary directory must be set
+** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
+** features that require the use of temporary files may fail. Here is an
+** example of how to do this using C++ with the Windows Runtime:
+**
+**
+** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
+** TemporaryFolder->Path->Data();
+** char zPathBuf[MAX_PATH + 1];
+** memset(zPathBuf, 0, sizeof(zPathBuf));
+** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
+** NULL, NULL);
+** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
+**
+*/
+SQLITE_API char *sqlite3_temp_directory;
+
+/*
+** CAPI3REF: Name Of The Folder Holding Database Files
+**
+** ^(If this global variable is made to point to a string which is
+** the name of a folder (a.k.a. directory), then all database files
+** specified with a relative pathname and created or accessed by
+** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
+** to be relative to that directory.)^ ^If this variable is a NULL
+** pointer, then SQLite assumes that all database files specified
+** with a relative pathname are relative to the current directory
+** for the process. Only the windows VFS makes use of this global
+** variable; it is ignored by the unix VFS.
+**
+** Changing the value of this variable while a database connection is
+** open can result in a corrupt database.
+**
+** It is not safe to read or modify this variable in more than one
+** thread at a time. It is not safe to read or modify this variable
+** if a [database connection] is being used at the same time in a separate
+** thread.
+** It is intended that this variable be set once
+** as part of process initialization and before any SQLite interface
+** routines have been called and that this variable remain unchanged
+** thereafter.
+**
+** ^The [data_store_directory pragma] may modify this variable and cause
+** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
+** the [data_store_directory pragma] always assumes that any string
+** that this variable points to is held in memory obtained from
+** [sqlite3_malloc] and the pragma may attempt to free that memory
+** using [sqlite3_free].
+** Hence, if this variable is modified directly, either it should be
+** made NULL or made to point to memory obtained from [sqlite3_malloc]
+** or else the use of the [data_store_directory pragma] should be avoided.
+*/
+SQLITE_API char *sqlite3_data_directory;
+
+/*
+** CAPI3REF: Test For Auto-Commit Mode
+** KEYWORDS: {autocommit mode}
+**
+** ^The sqlite3_get_autocommit() interface returns non-zero or
+** zero if the given database connection is or is not in autocommit mode,
+** respectively. ^Autocommit mode is on by default.
+** ^Autocommit mode is disabled by a [BEGIN] statement.
+** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
+**
+** If certain kinds of errors occur on a statement within a multi-statement
+** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
+** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
+** transaction might be rolled back automatically. The only way to
+** find out whether SQLite automatically rolled back the transaction after
+** an error is to use this function.
+**
+** If another thread changes the autocommit status of the database
+** connection while this routine is running, then the return value
+** is undefined.
+*/
+SQLITE_API int sqlite3_get_autocommit(sqlite3*);
+
+/*
+** CAPI3REF: Find The Database Handle Of A Prepared Statement
+**
+** ^The sqlite3_db_handle interface returns the [database connection] handle
+** to which a [prepared statement] belongs. ^The [database connection]
+** returned by sqlite3_db_handle is the same [database connection]
+** that was the first argument
+** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
+** create the statement in the first place.
+*/
+SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Return The Filename For A Database Connection
+**
+** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
+** associated with database N of connection D. ^The main database file
+** has the name "main". If there is no attached database N on the database
+** connection D, or if database N is a temporary or in-memory database, then
+** a NULL pointer is returned.
+**
+** ^The filename returned by this function is the output of the
+** xFullPathname method of the [VFS]. ^In other words, the filename
+** will be an absolute pathname, even if the filename used
+** to open the database originally was a URI or relative pathname.
+*/
+SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
+
+/*
+** CAPI3REF: Determine if a database is read-only
+**
+** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
+** of connection D is read-only, 0 if it is read/write, or -1 if N is not
+** the name of a database on connection D.
+*/
+SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
+
+/*
+** CAPI3REF: Find the next prepared statement
+**
+** ^This interface returns a pointer to the next [prepared statement] after
+** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
+** then this interface returns a pointer to the first prepared statement
+** associated with the database connection pDb. ^If no prepared statement
+** satisfies the conditions of this routine, it returns NULL.
+**
+** The [database connection] pointer D in a call to
+** [sqlite3_next_stmt(D,S)] must refer to an open database
+** connection and in particular must not be a NULL pointer.
+*/
+SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Commit And Rollback Notification Callbacks
+**
+** ^The sqlite3_commit_hook() interface registers a callback
+** function to be invoked whenever a transaction is [COMMIT | committed].
+** ^Any callback set by a previous call to sqlite3_commit_hook()
+** for the same database connection is overridden.
+** ^The sqlite3_rollback_hook() interface registers a callback
+** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
+** ^Any callback set by a previous call to sqlite3_rollback_hook()
+** for the same database connection is overridden.
+** ^The pArg argument is passed through to the callback.
+** ^If the callback on a commit hook function returns non-zero,
+** then the commit is converted into a rollback.
+**
+** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
+** return the P argument from the previous call of the same function
+** on the same [database connection] D, or NULL for
+** the first call for each function on D.
+**
+** The commit and rollback hook callbacks are not reentrant.
+** The callback implementation must not do anything that will modify
+** the database connection that invoked the callback. Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the commit
+** or rollback hook in the first place.
+** Note that running any other SQL statements, including SELECT statements,
+** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
+** the database connections for the meaning of "modify" in this paragraph.
+**
+** ^Registering a NULL function disables the callback.
+**
+** ^When the commit hook callback routine returns zero, the [COMMIT]
+** operation is allowed to continue normally. ^If the commit hook
+** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
+** ^The rollback hook is invoked on a rollback that results from a commit
+** hook returning non-zero, just as it would be with any other rollback.
+**
+** ^For the purposes of this API, a transaction is said to have been
+** rolled back if an explicit "ROLLBACK" statement is executed, or
+** an error or constraint causes an implicit rollback to occur.
+** ^The rollback callback is not invoked if a transaction is
+** automatically rolled back because the database connection is closed.
+**
+** See also the [sqlite3_update_hook()] interface.
+*/
+SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
+SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
+
+/*
+** CAPI3REF: Data Change Notification Callbacks
+**
+** ^The sqlite3_update_hook() interface registers a callback function
+** with the [database connection] identified by the first argument
+** to be invoked whenever a row is updated, inserted or deleted in
+** a rowid table.
+** ^Any callback set by a previous call to this function
+** for the same database connection is overridden.
+**
+** ^The second argument is a pointer to the function to invoke when a
+** row is updated, inserted or deleted in a rowid table.
+** ^The first argument to the callback is a copy of the third argument
+** to sqlite3_update_hook().
+** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
+** or [SQLITE_UPDATE], depending on the operation that caused the callback
+** to be invoked.
+** ^The third and fourth arguments to the callback contain pointers to the
+** database and table name containing the affected row.
+** ^The final callback parameter is the [rowid] of the row.
+** ^In the case of an update, this is the [rowid] after the update takes place.
+**
+** ^(The update hook is not invoked when internal system tables are
+** modified (i.e. sqlite_master and sqlite_sequence).)^
+** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
+**
+** ^In the current implementation, the update hook
+** is not invoked when duplication rows are deleted because of an
+** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
+** invoked when rows are deleted using the [truncate optimization].
+** The exceptions defined in this paragraph might change in a future
+** release of SQLite.
+**
+** The update hook implementation must not do anything that will modify
+** the database connection that invoked the update hook. Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the update hook.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** ^The sqlite3_update_hook(D,C,P) function
+** returns the P argument from the previous call
+** on the same [database connection] D, or NULL for
+** the first call on D.
+**
+** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
+** interfaces.
+*/
+SQLITE_API void *sqlite3_update_hook(
+ sqlite3*,
+ void(*)(void *,int ,char const *,char const *,sqlite3_int64),
+ void*
+);
+
+/*
+** CAPI3REF: Enable Or Disable Shared Pager Cache
+**
+** ^(This routine enables or disables the sharing of the database cache
+** and schema data structures between [database connection | connections]
+** to the same database. Sharing is enabled if the argument is true
+** and disabled if the argument is false.)^
+**
+** ^Cache sharing is enabled and disabled for an entire process.
+** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
+** sharing was enabled or disabled for each thread separately.
+**
+** ^(The cache sharing mode set by this interface effects all subsequent
+** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
+** Existing database connections continue use the sharing mode
+** that was in effect at the time they were opened.)^
+**
+** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
+** successfully. An [error code] is returned otherwise.)^
+**
+** ^Shared cache is disabled by default. But this might change in
+** future releases of SQLite. Applications that care about shared
+** cache setting should set it explicitly.
+**
+** This interface is threadsafe on processors where writing a
+** 32-bit integer is atomic.
+**
+** See Also: [SQLite Shared-Cache Mode]
+*/
+SQLITE_API int sqlite3_enable_shared_cache(int);
+
+/*
+** CAPI3REF: Attempt To Free Heap Memory
+**
+** ^The sqlite3_release_memory() interface attempts to free N bytes
+** of heap memory by deallocating non-essential memory allocations
+** held by the database library. Memory used to cache database
+** pages to improve performance is an example of non-essential memory.
+** ^sqlite3_release_memory() returns the number of bytes actually freed,
+** which might be more or less than the amount requested.
+** ^The sqlite3_release_memory() routine is a no-op returning zero
+** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** See also: [sqlite3_db_release_memory()]
+*/
+SQLITE_API int sqlite3_release_memory(int);
+
+/*
+** CAPI3REF: Free Memory Used By A Database Connection
+**
+** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
+** memory as possible from database connection D. Unlike the
+** [sqlite3_release_memory()] interface, this interface is in effect even
+** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
+** omitted.
+**
+** See also: [sqlite3_release_memory()]
+*/
+SQLITE_API int sqlite3_db_release_memory(sqlite3*);
+
+/*
+** CAPI3REF: Impose A Limit On Heap Size
+**
+** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
+** soft limit on the amount of heap memory that may be allocated by SQLite.
+** ^SQLite strives to keep heap memory utilization below the soft heap
+** limit by reducing the number of pages held in the page cache
+** as heap memory usages approaches the limit.
+** ^The soft heap limit is "soft" because even though SQLite strives to stay
+** below the limit, it will exceed the limit rather than generate
+** an [SQLITE_NOMEM] error. In other words, the soft heap limit
+** is advisory only.
+**
+** ^The return value from sqlite3_soft_heap_limit64() is the size of
+** the soft heap limit prior to the call, or negative in the case of an
+** error. ^If the argument N is negative
+** then no change is made to the soft heap limit. Hence, the current
+** size of the soft heap limit can be determined by invoking
+** sqlite3_soft_heap_limit64() with a negative argument.
+**
+** ^If the argument N is zero then the soft heap limit is disabled.
+**
+** ^(The soft heap limit is not enforced in the current implementation
+** if one or more of following conditions are true:
+**
+**
+** - The soft heap limit is set to zero.
+**
- Memory accounting is disabled using a combination of the
+** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
+** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
+**
- An alternative page cache implementation is specified using
+** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
+**
- The page cache allocates from its own memory pool supplied
+** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
+** from the heap.
+**
)^
+**
+** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
+** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
+** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
+** the soft heap limit is enforced on every memory allocation. Without
+** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
+** when memory is allocated by the page cache. Testing suggests that because
+** the page cache is the predominate memory user in SQLite, most
+** applications will achieve adequate soft heap limit enforcement without
+** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** The circumstances under which SQLite will enforce the soft heap limit may
+** changes in future releases of SQLite.
+*/
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
+
+/*
+** CAPI3REF: Deprecated Soft Heap Limit Interface
+** DEPRECATED
+**
+** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
+** interface. This routine is provided for historical compatibility
+** only. All new applications should use the
+** [sqlite3_soft_heap_limit64()] interface rather than this one.
+*/
+SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
+
+
+/*
+** CAPI3REF: Extract Metadata About A Column Of A Table
+**
+** ^This routine returns metadata about a specific column of a specific
+** database table accessible using the [database connection] handle
+** passed as the first function argument.
+**
+** ^The column is identified by the second, third and fourth parameters to
+** this function. ^The second parameter is either the name of the database
+** (i.e. "main", "temp", or an attached database) containing the specified
+** table or NULL. ^If it is NULL, then all attached databases are searched
+** for the table using the same algorithm used by the database engine to
+** resolve unqualified table references.
+**
+** ^The third and fourth parameters to this function are the table and column
+** name of the desired column, respectively. Neither of these parameters
+** may be NULL.
+**
+** ^Metadata is returned by writing to the memory locations passed as the 5th
+** and subsequent parameters to this function. ^Any of these arguments may be
+** NULL, in which case the corresponding element of metadata is omitted.
+**
+** ^(
+**
+** Parameter | Output Type | Description
+**
+** |
---|
5th | const char* | Data type
+** |
6th | const char* | Name of default collation sequence
+** |
7th | int | True if column has a NOT NULL constraint
+** |
8th | int | True if column is part of the PRIMARY KEY
+** |
9th | int | True if column is [AUTOINCREMENT]
+** |
+**
)^
+**
+** ^The memory pointed to by the character pointers returned for the
+** declaration type and collation sequence is valid only until the next
+** call to any SQLite API function.
+**
+** ^If the specified table is actually a view, an [error code] is returned.
+**
+** ^If the specified column is "rowid", "oid" or "_rowid_" and an
+** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
+** parameters are set for the explicitly declared column. ^(If there is no
+** explicitly declared [INTEGER PRIMARY KEY] column, then the output
+** parameters are set as follows:
+**
+**
+** data type: "INTEGER"
+** collation sequence: "BINARY"
+** not null: 0
+** primary key: 1
+** auto increment: 0
+**
)^
+**
+** ^(This function may load one or more schemas from database files. If an
+** error occurs during this process, or if the requested table or column
+** cannot be found, an [error code] is returned and an error message left
+** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
+**
+** ^This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
+*/
+SQLITE_API int sqlite3_table_column_metadata(
+ sqlite3 *db, /* Connection handle */
+ const char *zDbName, /* Database name or NULL */
+ const char *zTableName, /* Table name */
+ const char *zColumnName, /* Column name */
+ char const **pzDataType, /* OUTPUT: Declared data type */
+ char const **pzCollSeq, /* OUTPUT: Collation sequence name */
+ int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
+ int *pPrimaryKey, /* OUTPUT: True if column part of PK */
+ int *pAutoinc /* OUTPUT: True if column is auto-increment */
+);
+
+/*
+** CAPI3REF: Load An Extension
+**
+** ^This interface loads an SQLite extension library from the named file.
+**
+** ^The sqlite3_load_extension() interface attempts to load an
+** [SQLite extension] library contained in the file zFile. If
+** the file cannot be loaded directly, attempts are made to load
+** with various operating-system specific extensions added.
+** So for example, if "samplelib" cannot be loaded, then names like
+** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
+** be tried also.
+**
+** ^The entry point is zProc.
+** ^(zProc may be 0, in which case SQLite will try to come up with an
+** entry point name on its own. It first tries "sqlite3_extension_init".
+** If that does not work, it constructs a name "sqlite3_X_init" where the
+** X is consists of the lower-case equivalent of all ASCII alphabetic
+** characters in the filename from the last "/" to the first following
+** "." and omitting any initial "lib".)^
+** ^The sqlite3_load_extension() interface returns
+** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+** ^If an error occurs and pzErrMsg is not 0, then the
+** [sqlite3_load_extension()] interface shall attempt to
+** fill *pzErrMsg with error message text stored in memory
+** obtained from [sqlite3_malloc()]. The calling function
+** should free this memory by calling [sqlite3_free()].
+**
+** ^Extension loading must be enabled using
+** [sqlite3_enable_load_extension()] prior to calling this API,
+** otherwise an error will be returned.
+**
+** See also the [load_extension() SQL function].
+*/
+SQLITE_API int sqlite3_load_extension(
+ sqlite3 *db, /* Load the extension into this database connection */
+ const char *zFile, /* Name of the shared library containing extension */
+ const char *zProc, /* Entry point. Derived from zFile if 0 */
+ char **pzErrMsg /* Put error message here if not 0 */
+);
+
+/*
+** CAPI3REF: Enable Or Disable Extension Loading
+**
+** ^So as not to open security holes in older applications that are
+** unprepared to deal with [extension loading], and as a means of disabling
+** [extension loading] while evaluating user-entered SQL, the following API
+** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
+**
+** ^Extension loading is off by default.
+** ^Call the sqlite3_enable_load_extension() routine with onoff==1
+** to turn extension loading on and call it with onoff==0 to turn
+** it back off again.
+*/
+SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
+
+/*
+** CAPI3REF: Automatically Load Statically Linked Extensions
+**
+** ^This interface causes the xEntryPoint() function to be invoked for
+** each new [database connection] that is created. The idea here is that
+** xEntryPoint() is the entry point for a statically linked [SQLite extension]
+** that is to be automatically loaded into all new database connections.
+**
+** ^(Even though the function prototype shows that xEntryPoint() takes
+** no arguments and returns void, SQLite invokes xEntryPoint() with three
+** arguments and expects and integer result as if the signature of the
+** entry point where as follows:
+**
+**
+** int xEntryPoint(
+** sqlite3 *db,
+** const char **pzErrMsg,
+** const struct sqlite3_api_routines *pThunk
+** );
+**
)^
+**
+** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
+** point to an appropriate error message (obtained from [sqlite3_mprintf()])
+** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
+** is NULL before calling the xEntryPoint(). ^SQLite will invoke
+** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
+** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
+** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
+**
+** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
+** on the list of automatic extensions is a harmless no-op. ^No entry point
+** will be called more than once for each database connection that is opened.
+**
+** See also: [sqlite3_reset_auto_extension()]
+** and [sqlite3_cancel_auto_extension()]
+*/
+SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
+
+/*
+** CAPI3REF: Cancel Automatic Extension Loading
+**
+** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
+** initialization routine X that was registered using a prior call to
+** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
+** routine returns 1 if initialization routine X was successfully
+** unregistered and it returns 0 if X was not on the list of initialization
+** routines.
+*/
+SQLITE_API int sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
+
+/*
+** CAPI3REF: Reset Automatic Extension Loading
+**
+** ^This interface disables all automatic extensions previously
+** registered using [sqlite3_auto_extension()].
+*/
+SQLITE_API void sqlite3_reset_auto_extension(void);
+
+/*
+** The interface to the virtual-table mechanism is currently considered
+** to be experimental. The interface might change in incompatible ways.
+** If this is a problem for you, do not use the interface at this time.
+**
+** When the virtual-table mechanism stabilizes, we will declare the
+** interface fixed, support it indefinitely, and remove this comment.
+*/
+
+/*
+** Structures used by the virtual table interface
+*/
+typedef struct sqlite3_vtab sqlite3_vtab;
+typedef struct sqlite3_index_info sqlite3_index_info;
+typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
+typedef struct sqlite3_module sqlite3_module;
+
+/*
+** CAPI3REF: Virtual Table Object
+** KEYWORDS: sqlite3_module {virtual table module}
+**
+** This structure, sometimes called a "virtual table module",
+** defines the implementation of a [virtual tables].
+** This structure consists mostly of methods for the module.
+**
+** ^A virtual table module is created by filling in a persistent
+** instance of this structure and passing a pointer to that instance
+** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
+** ^The registration remains valid until it is replaced by a different
+** module or until the [database connection] closes. The content
+** of this structure must not change while it is registered with
+** any database connection.
+*/
+struct sqlite3_module {
+ int iVersion;
+ int (*xCreate)(sqlite3*, void *pAux,
+ int argc, const char *const*argv,
+ sqlite3_vtab **ppVTab, char**);
+ int (*xConnect)(sqlite3*, void *pAux,
+ int argc, const char *const*argv,
+ sqlite3_vtab **ppVTab, char**);
+ int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
+ int (*xDisconnect)(sqlite3_vtab *pVTab);
+ int (*xDestroy)(sqlite3_vtab *pVTab);
+ int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
+ int (*xClose)(sqlite3_vtab_cursor*);
+ int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
+ int argc, sqlite3_value **argv);
+ int (*xNext)(sqlite3_vtab_cursor*);
+ int (*xEof)(sqlite3_vtab_cursor*);
+ int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
+ int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
+ int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
+ int (*xBegin)(sqlite3_vtab *pVTab);
+ int (*xSync)(sqlite3_vtab *pVTab);
+ int (*xCommit)(sqlite3_vtab *pVTab);
+ int (*xRollback)(sqlite3_vtab *pVTab);
+ int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
+ void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
+ void **ppArg);
+ int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
+ /* The methods above are in version 1 of the sqlite_module object. Those
+ ** below are for version 2 and greater. */
+ int (*xSavepoint)(sqlite3_vtab *pVTab, int);
+ int (*xRelease)(sqlite3_vtab *pVTab, int);
+ int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
+};
+
+/*
+** CAPI3REF: Virtual Table Indexing Information
+** KEYWORDS: sqlite3_index_info
+**
+** The sqlite3_index_info structure and its substructures is used as part
+** of the [virtual table] interface to
+** pass information into and receive the reply from the [xBestIndex]
+** method of a [virtual table module]. The fields under **Inputs** are the
+** inputs to xBestIndex and are read-only. xBestIndex inserts its
+** results into the **Outputs** fields.
+**
+** ^(The aConstraint[] array records WHERE clause constraints of the form:
+**
+** column OP expr
+**
+** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
+** stored in aConstraint[].op using one of the
+** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
+** ^(The index of the column is stored in
+** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
+** expr on the right-hand side can be evaluated (and thus the constraint
+** is usable) and false if it cannot.)^
+**
+** ^The optimizer automatically inverts terms of the form "expr OP column"
+** and makes other simplifications to the WHERE clause in an attempt to
+** get as many WHERE clause terms into the form shown above as possible.
+** ^The aConstraint[] array only reports WHERE clause terms that are
+** relevant to the particular virtual table being queried.
+**
+** ^Information about the ORDER BY clause is stored in aOrderBy[].
+** ^Each term of aOrderBy records a column of the ORDER BY clause.
+**
+** The [xBestIndex] method must fill aConstraintUsage[] with information
+** about what parameters to pass to xFilter. ^If argvIndex>0 then
+** the right-hand side of the corresponding aConstraint[] is evaluated
+** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
+** is true, then the constraint is assumed to be fully handled by the
+** virtual table and is not checked again by SQLite.)^
+**
+** ^The idxNum and idxPtr values are recorded and passed into the
+** [xFilter] method.
+** ^[sqlite3_free()] is used to free idxPtr if and only if
+** needToFreeIdxPtr is true.
+**
+** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
+** the correct order to satisfy the ORDER BY clause so that no separate
+** sorting step is required.
+**
+** ^The estimatedCost value is an estimate of the cost of a particular
+** strategy. A cost of N indicates that the cost of the strategy is similar
+** to a linear scan of an SQLite table with N rows. A cost of log(N)
+** indicates that the expense of the operation is similar to that of a
+** binary search on a unique indexed field of an SQLite table with N rows.
+**
+** ^The estimatedRows value is an estimate of the number of rows that
+** will be returned by the strategy.
+**
+** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
+** structure for SQLite version 3.8.2. If a virtual table extension is
+** used with an SQLite version earlier than 3.8.2, the results of attempting
+** to read or write the estimatedRows field are undefined (but are likely
+** to included crashing the application). The estimatedRows field should
+** therefore only be used if [sqlite3_libversion_number()] returns a
+** value greater than or equal to 3008002.
+*/
+struct sqlite3_index_info {
+ /* Inputs */
+ int nConstraint; /* Number of entries in aConstraint */
+ struct sqlite3_index_constraint {
+ int iColumn; /* Column on left-hand side of constraint */
+ unsigned char op; /* Constraint operator */
+ unsigned char usable; /* True if this constraint is usable */
+ int iTermOffset; /* Used internally - xBestIndex should ignore */
+ } *aConstraint; /* Table of WHERE clause constraints */
+ int nOrderBy; /* Number of terms in the ORDER BY clause */
+ struct sqlite3_index_orderby {
+ int iColumn; /* Column number */
+ unsigned char desc; /* True for DESC. False for ASC. */
+ } *aOrderBy; /* The ORDER BY clause */
+ /* Outputs */
+ struct sqlite3_index_constraint_usage {
+ int argvIndex; /* if >0, constraint is part of argv to xFilter */
+ unsigned char omit; /* Do not code a test for this constraint */
+ } *aConstraintUsage;
+ int idxNum; /* Number used to identify the index */
+ char *idxStr; /* String, possibly obtained from sqlite3_malloc */
+ int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
+ int orderByConsumed; /* True if output is already ordered */
+ double estimatedCost; /* Estimated cost of using this index */
+ /* Fields below are only available in SQLite 3.8.2 and later */
+ sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
+};
+
+/*
+** CAPI3REF: Virtual Table Constraint Operator Codes
+**
+** These macros defined the allowed values for the
+** [sqlite3_index_info].aConstraint[].op field. Each value represents
+** an operator that is part of a constraint term in the wHERE clause of
+** a query that uses a [virtual table].
+*/
+#define SQLITE_INDEX_CONSTRAINT_EQ 2
+#define SQLITE_INDEX_CONSTRAINT_GT 4
+#define SQLITE_INDEX_CONSTRAINT_LE 8
+#define SQLITE_INDEX_CONSTRAINT_LT 16
+#define SQLITE_INDEX_CONSTRAINT_GE 32
+#define SQLITE_INDEX_CONSTRAINT_MATCH 64
+
+/*
+** CAPI3REF: Register A Virtual Table Implementation
+**
+** ^These routines are used to register a new [virtual table module] name.
+** ^Module names must be registered before
+** creating a new [virtual table] using the module and before using a
+** preexisting [virtual table] for the module.
+**
+** ^The module name is registered on the [database connection] specified
+** by the first parameter. ^The name of the module is given by the
+** second parameter. ^The third parameter is a pointer to
+** the implementation of the [virtual table module]. ^The fourth
+** parameter is an arbitrary client data pointer that is passed through
+** into the [xCreate] and [xConnect] methods of the virtual table module
+** when a new virtual table is be being created or reinitialized.
+**
+** ^The sqlite3_create_module_v2() interface has a fifth parameter which
+** is a pointer to a destructor for the pClientData. ^SQLite will
+** invoke the destructor function (if it is not NULL) when SQLite
+** no longer needs the pClientData pointer. ^The destructor will also
+** be invoked if the call to sqlite3_create_module_v2() fails.
+** ^The sqlite3_create_module()
+** interface is equivalent to sqlite3_create_module_v2() with a NULL
+** destructor.
+*/
+SQLITE_API int sqlite3_create_module(
+ sqlite3 *db, /* SQLite connection to register module with */
+ const char *zName, /* Name of the module */
+ const sqlite3_module *p, /* Methods for the module */
+ void *pClientData /* Client data for xCreate/xConnect */
+);
+SQLITE_API int sqlite3_create_module_v2(
+ sqlite3 *db, /* SQLite connection to register module with */
+ const char *zName, /* Name of the module */
+ const sqlite3_module *p, /* Methods for the module */
+ void *pClientData, /* Client data for xCreate/xConnect */
+ void(*xDestroy)(void*) /* Module destructor function */
+);
+
+/*
+** CAPI3REF: Virtual Table Instance Object
+** KEYWORDS: sqlite3_vtab
+**
+** Every [virtual table module] implementation uses a subclass
+** of this object to describe a particular instance
+** of the [virtual table]. Each subclass will
+** be tailored to the specific needs of the module implementation.
+** The purpose of this superclass is to define certain fields that are
+** common to all module implementations.
+**
+** ^Virtual tables methods can set an error message by assigning a
+** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
+** take care that any prior string is freed by a call to [sqlite3_free()]
+** prior to assigning a new string to zErrMsg. ^After the error message
+** is delivered up to the client application, the string will be automatically
+** freed by sqlite3_free() and the zErrMsg field will be zeroed.
+*/
+struct sqlite3_vtab {
+ const sqlite3_module *pModule; /* The module for this virtual table */
+ int nRef; /* NO LONGER USED */
+ char *zErrMsg; /* Error message from sqlite3_mprintf() */
+ /* Virtual table implementations will typically add additional fields */
+};
+
+/*
+** CAPI3REF: Virtual Table Cursor Object
+** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
+**
+** Every [virtual table module] implementation uses a subclass of the
+** following structure to describe cursors that point into the
+** [virtual table] and are used
+** to loop through the virtual table. Cursors are created using the
+** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
+** by the [sqlite3_module.xClose | xClose] method. Cursors are used
+** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
+** of the module. Each module implementation will define
+** the content of a cursor structure to suit its own needs.
+**
+** This superclass exists in order to define fields of the cursor that
+** are common to all implementations.
+*/
+struct sqlite3_vtab_cursor {
+ sqlite3_vtab *pVtab; /* Virtual table of this cursor */
+ /* Virtual table implementations will typically add additional fields */
+};
+
+/*
+** CAPI3REF: Declare The Schema Of A Virtual Table
+**
+** ^The [xCreate] and [xConnect] methods of a
+** [virtual table module] call this interface
+** to declare the format (the names and datatypes of the columns) of
+** the virtual tables they implement.
+*/
+SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
+
+/*
+** CAPI3REF: Overload A Function For A Virtual Table
+**
+** ^(Virtual tables can provide alternative implementations of functions
+** using the [xFindFunction] method of the [virtual table module].
+** But global versions of those functions
+** must exist in order to be overloaded.)^
+**
+** ^(This API makes sure a global version of a function with a particular
+** name and number of parameters exists. If no such function exists
+** before this API is called, a new function is created.)^ ^The implementation
+** of the new function always causes an exception to be thrown. So
+** the new function is not good for anything by itself. Its only
+** purpose is to be a placeholder function that can be overloaded
+** by a [virtual table].
+*/
+SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
+
+/*
+** The interface to the virtual-table mechanism defined above (back up
+** to a comment remarkably similar to this one) is currently considered
+** to be experimental. The interface might change in incompatible ways.
+** If this is a problem for you, do not use the interface at this time.
+**
+** When the virtual-table mechanism stabilizes, we will declare the
+** interface fixed, support it indefinitely, and remove this comment.
+*/
+
+/*
+** CAPI3REF: A Handle To An Open BLOB
+** KEYWORDS: {BLOB handle} {BLOB handles}
+**
+** An instance of this object represents an open BLOB on which
+** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
+** ^Objects of this type are created by [sqlite3_blob_open()]
+** and destroyed by [sqlite3_blob_close()].
+** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
+** can be used to read or write small subsections of the BLOB.
+** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
+*/
+typedef struct sqlite3_blob sqlite3_blob;
+
+/*
+** CAPI3REF: Open A BLOB For Incremental I/O
+**
+** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
+** in row iRow, column zColumn, table zTable in database zDb;
+** in other words, the same BLOB that would be selected by:
+**
+**
+** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
+**
)^
+**
+** ^If the flags parameter is non-zero, then the BLOB is opened for read
+** and write access. ^If it is zero, the BLOB is opened for read access.
+** ^It is not possible to open a column that is part of an index or primary
+** key for writing. ^If [foreign key constraints] are enabled, it is
+** not possible to open a column that is part of a [child key] for writing.
+**
+** ^Note that the database name is not the filename that contains
+** the database but rather the symbolic name of the database that
+** appears after the AS keyword when the database is connected using [ATTACH].
+** ^For the main database file, the database name is "main".
+** ^For TEMP tables, the database name is "temp".
+**
+** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
+** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
+** to be a null pointer.)^
+** ^This function sets the [database connection] error code and message
+** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
+** functions. ^Note that the *ppBlob variable is always initialized in a
+** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
+** regardless of the success or failure of this routine.
+**
+** ^(If the row that a BLOB handle points to is modified by an
+** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
+** then the BLOB handle is marked as "expired".
+** This is true if any column of the row is changed, even a column
+** other than the one the BLOB handle is open on.)^
+** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
+** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
+** ^(Changes written into a BLOB prior to the BLOB expiring are not
+** rolled back by the expiration of the BLOB. Such changes will eventually
+** commit if the transaction continues to completion.)^
+**
+** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
+** the opened blob. ^The size of a blob may not be changed by this
+** interface. Use the [UPDATE] SQL command to change the size of a
+** blob.
+**
+** ^The [sqlite3_blob_open()] interface will fail for a [WITHOUT ROWID]
+** table. Incremental BLOB I/O is not possible on [WITHOUT ROWID] tables.
+**
+** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
+** and the built-in [zeroblob] SQL function can be used, if desired,
+** to create an empty, zero-filled blob in which to read or write using
+** this interface.
+**
+** To avoid a resource leak, every open [BLOB handle] should eventually
+** be released by a call to [sqlite3_blob_close()].
+*/
+SQLITE_API int sqlite3_blob_open(
+ sqlite3*,
+ const char *zDb,
+ const char *zTable,
+ const char *zColumn,
+ sqlite3_int64 iRow,
+ int flags,
+ sqlite3_blob **ppBlob
+);
+
+/*
+** CAPI3REF: Move a BLOB Handle to a New Row
+**
+** ^This function is used to move an existing blob handle so that it points
+** to a different row of the same database table. ^The new row is identified
+** by the rowid value passed as the second argument. Only the row can be
+** changed. ^The database, table and column on which the blob handle is open
+** remain the same. Moving an existing blob handle to a new row can be
+** faster than closing the existing handle and opening a new one.
+**
+** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
+** it must exist and there must be either a blob or text value stored in
+** the nominated column.)^ ^If the new row is not present in the table, or if
+** it does not contain a blob or text value, or if another error occurs, an
+** SQLite error code is returned and the blob handle is considered aborted.
+** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
+** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
+** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
+** always returns zero.
+**
+** ^This function sets the database handle error code and message.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
+
+/*
+** CAPI3REF: Close A BLOB Handle
+**
+** ^Closes an open [BLOB handle].
+**
+** ^Closing a BLOB shall cause the current transaction to commit
+** if there are no other BLOBs, no pending prepared statements, and the
+** database connection is in [autocommit mode].
+** ^If any writes were made to the BLOB, they might be held in cache
+** until the close operation if they will fit.
+**
+** ^(Closing the BLOB often forces the changes
+** out to disk and so if any I/O errors occur, they will likely occur
+** at the time when the BLOB is closed. Any errors that occur during
+** closing are reported as a non-zero return value.)^
+**
+** ^(The BLOB is closed unconditionally. Even if this routine returns
+** an error code, the BLOB is still closed.)^
+**
+** ^Calling this routine with a null pointer (such as would be returned
+** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
+*/
+SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
+
+/*
+** CAPI3REF: Return The Size Of An Open BLOB
+**
+** ^Returns the size in bytes of the BLOB accessible via the
+** successfully opened [BLOB handle] in its only argument. ^The
+** incremental blob I/O routines can only read or overwriting existing
+** blob content; they cannot change the size of a blob.
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()]. Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+*/
+SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
+
+/*
+** CAPI3REF: Read Data From A BLOB Incrementally
+**
+** ^(This function is used to read data from an open [BLOB handle] into a
+** caller-supplied buffer. N bytes of data are copied into buffer Z
+** from the open BLOB, starting at offset iOffset.)^
+**
+** ^If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
+** less than zero, [SQLITE_ERROR] is returned and no data is read.
+** ^The size of the blob (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
+**
+** ^An attempt to read from an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].
+**
+** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
+** Otherwise, an [error code] or an [extended error code] is returned.)^
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()]. Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+**
+** See also: [sqlite3_blob_write()].
+*/
+SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
+
+/*
+** CAPI3REF: Write Data Into A BLOB Incrementally
+**
+** ^This function is used to write data into an open [BLOB handle] from a
+** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
+** into the open BLOB, starting at offset iOffset.
+**
+** ^If the [BLOB handle] passed as the first argument was not opened for
+** writing (the flags parameter to [sqlite3_blob_open()] was zero),
+** this function returns [SQLITE_READONLY].
+**
+** ^This function may only modify the contents of the BLOB; it is
+** not possible to increase the size of a BLOB using this API.
+** ^If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is written. ^If N is
+** less than zero [SQLITE_ERROR] is returned and no data is written.
+** The size of the BLOB (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
+**
+** ^An attempt to write to an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
+** before the [BLOB handle] expired are not rolled back by the
+** expiration of the handle, though of course those changes might
+** have been overwritten by the statement that expired the BLOB handle
+** or by other independent statements.
+**
+** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
+** Otherwise, an [error code] or an [extended error code] is returned.)^
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()]. Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+**
+** See also: [sqlite3_blob_read()].
+*/
+SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
+
+/*
+** CAPI3REF: Virtual File System Objects
+**
+** A virtual filesystem (VFS) is an [sqlite3_vfs] object
+** that SQLite uses to interact
+** with the underlying operating system. Most SQLite builds come with a
+** single default VFS that is appropriate for the host computer.
+** New VFSes can be registered and existing VFSes can be unregistered.
+** The following interfaces are provided.
+**
+** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
+** ^Names are case sensitive.
+** ^Names are zero-terminated UTF-8 strings.
+** ^If there is no match, a NULL pointer is returned.
+** ^If zVfsName is NULL then the default VFS is returned.
+**
+** ^New VFSes are registered with sqlite3_vfs_register().
+** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
+** ^The same VFS can be registered multiple times without injury.
+** ^To make an existing VFS into the default VFS, register it again
+** with the makeDflt flag set. If two different VFSes with the
+** same name are registered, the behavior is undefined. If a
+** VFS is registered with a name that is NULL or an empty string,
+** then the behavior is undefined.
+**
+** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
+** ^(If the default VFS is unregistered, another VFS is chosen as
+** the default. The choice for the new VFS is arbitrary.)^
+*/
+SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
+SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
+SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
+
+/*
+** CAPI3REF: Mutexes
+**
+** The SQLite core uses these routines for thread
+** synchronization. Though they are intended for internal
+** use by SQLite, code that links against SQLite is
+** permitted to use any of these routines.
+**
+** The SQLite source code contains multiple implementations
+** of these mutex routines. An appropriate implementation
+** is selected automatically at compile-time. ^(The following
+** implementations are available in the SQLite core:
+**
+**
+** - SQLITE_MUTEX_PTHREADS
+**
- SQLITE_MUTEX_W32
+**
- SQLITE_MUTEX_NOOP
+**
)^
+**
+** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
+** that does no real locking and is appropriate for use in
+** a single-threaded application. ^The SQLITE_MUTEX_PTHREADS and
+** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
+** and Windows.
+**
+** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
+** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
+** implementation is included with the library. In this case the
+** application must supply a custom mutex implementation using the
+** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
+** before calling sqlite3_initialize() or any other public sqlite3_
+** function that calls sqlite3_initialize().)^
+**
+** ^The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. ^If it returns NULL
+** that means that a mutex could not be allocated. ^SQLite
+** will unwind its stack and return an error. ^(The argument
+** to sqlite3_mutex_alloc() is one of these integer constants:
+**
+**
+** - SQLITE_MUTEX_FAST
+**
- SQLITE_MUTEX_RECURSIVE
+**
- SQLITE_MUTEX_STATIC_MASTER
+**
- SQLITE_MUTEX_STATIC_MEM
+**
- SQLITE_MUTEX_STATIC_MEM2
+**
- SQLITE_MUTEX_STATIC_PRNG
+**
- SQLITE_MUTEX_STATIC_LRU
+**
- SQLITE_MUTEX_STATIC_LRU2
+**
)^
+**
+** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
+** cause sqlite3_mutex_alloc() to create
+** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
+** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
+** The mutex implementation does not need to make a distinction
+** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
+** not want to. ^SQLite will only request a recursive mutex in
+** cases where it really needs one. ^If a faster non-recursive mutex
+** implementation is available on the host platform, the mutex subsystem
+** might return such a mutex in response to SQLITE_MUTEX_FAST.
+**
+** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
+** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
+** a pointer to a static preexisting mutex. ^Six static mutexes are
+** used by the current version of SQLite. Future versions of SQLite
+** may add additional static mutexes. Static mutexes are for internal
+** use by SQLite only. Applications that use SQLite mutexes should
+** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
+** SQLITE_MUTEX_RECURSIVE.
+**
+** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
+** returns a different mutex on every call. ^But for the static
+** mutex types, the same mutex is returned on every call that has
+** the same type number.
+**
+** ^The sqlite3_mutex_free() routine deallocates a previously
+** allocated dynamic mutex. ^SQLite is careful to deallocate every
+** dynamic mutex that it allocates. The dynamic mutexes must not be in
+** use when they are deallocated. Attempting to deallocate a static
+** mutex results in undefined behavior. ^SQLite never deallocates
+** a static mutex.
+**
+** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. ^If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
+** upon successful entry. ^(Mutexes created using
+** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
+** In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter.)^ ^(If the same thread tries to enter any other
+** kind of mutex more than once, the behavior is undefined.
+** SQLite will never exhibit
+** such behavior in its own use of mutexes.)^
+**
+** ^(Some systems (for example, Windows 95) do not support the operation
+** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
+** will always return SQLITE_BUSY. The SQLite core only ever uses
+** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
+**
+** ^The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. ^(The behavior
+** is undefined if the mutex is not currently entered by the
+** calling thread or is not currently allocated. SQLite will
+** never do either.)^
+**
+** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
+** sqlite3_mutex_leave() is a NULL pointer, then all three routines
+** behave as no-ops.
+**
+** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
+*/
+SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
+SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
+
+/*
+** CAPI3REF: Mutex Methods Object
+**
+** An instance of this structure defines the low-level routines
+** used to allocate and use mutexes.
+**
+** Usually, the default mutex implementations provided by SQLite are
+** sufficient, however the user has the option of substituting a custom
+** implementation for specialized deployments or systems for which SQLite
+** does not provide a suitable implementation. In this case, the user
+** creates and populates an instance of this structure to pass
+** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
+** Additionally, an instance of this structure can be used as an
+** output variable when querying the system for the current mutex
+** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
+**
+** ^The xMutexInit method defined by this structure is invoked as
+** part of system initialization by the sqlite3_initialize() function.
+** ^The xMutexInit routine is called by SQLite exactly once for each
+** effective call to [sqlite3_initialize()].
+**
+** ^The xMutexEnd method defined by this structure is invoked as
+** part of system shutdown by the sqlite3_shutdown() function. The
+** implementation of this method is expected to release all outstanding
+** resources obtained by the mutex methods implementation, especially
+** those obtained by the xMutexInit method. ^The xMutexEnd()
+** interface is invoked exactly once for each call to [sqlite3_shutdown()].
+**
+** ^(The remaining seven methods defined by this structure (xMutexAlloc,
+** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
+** xMutexNotheld) implement the following interfaces (respectively):
+**
+**
+** - [sqlite3_mutex_alloc()]
+** - [sqlite3_mutex_free()]
+** - [sqlite3_mutex_enter()]
+** - [sqlite3_mutex_try()]
+** - [sqlite3_mutex_leave()]
+** - [sqlite3_mutex_held()]
+** - [sqlite3_mutex_notheld()]
+**
)^
+**
+** The only difference is that the public sqlite3_XXX functions enumerated
+** above silently ignore any invocations that pass a NULL pointer instead
+** of a valid mutex handle. The implementations of the methods defined
+** by this structure are not required to handle this case, the results
+** of passing a NULL pointer instead of a valid mutex handle are undefined
+** (i.e. it is acceptable to provide an implementation that segfaults if
+** it is passed a NULL pointer).
+**
+** The xMutexInit() method must be threadsafe. ^It must be harmless to
+** invoke xMutexInit() multiple times within the same process and without
+** intervening calls to xMutexEnd(). Second and subsequent calls to
+** xMutexInit() must be no-ops.
+**
+** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
+** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
+** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
+** memory allocation for a fast or recursive mutex.
+**
+** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
+** called, but only if the prior call to xMutexInit returned SQLITE_OK.
+** If xMutexInit fails in any way, it is expected to clean up after itself
+** prior to returning.
+*/
+typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
+struct sqlite3_mutex_methods {
+ int (*xMutexInit)(void);
+ int (*xMutexEnd)(void);
+ sqlite3_mutex *(*xMutexAlloc)(int);
+ void (*xMutexFree)(sqlite3_mutex *);
+ void (*xMutexEnter)(sqlite3_mutex *);
+ int (*xMutexTry)(sqlite3_mutex *);
+ void (*xMutexLeave)(sqlite3_mutex *);
+ int (*xMutexHeld)(sqlite3_mutex *);
+ int (*xMutexNotheld)(sqlite3_mutex *);
+};
+
+/*
+** CAPI3REF: Mutex Verification Routines
+**
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
+** are intended for use inside assert() statements. ^The SQLite core
+** never uses these routines except inside an assert() and applications
+** are advised to follow the lead of the core. ^The SQLite core only
+** provides implementations for these routines when it is compiled
+** with the SQLITE_DEBUG flag. ^External mutex implementations
+** are only required to provide these routines if SQLITE_DEBUG is
+** defined and if NDEBUG is not defined.
+**
+** ^These routines should return true if the mutex in their argument
+** is held or not held, respectively, by the calling thread.
+**
+** ^The implementation is not required to provide versions of these
+** routines that actually work. If the implementation does not provide working
+** versions of these routines, it should at least provide stubs that always
+** return true so that one does not get spurious assertion failures.
+**
+** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
+** the routine should return 1. This seems counter-intuitive since
+** clearly the mutex cannot be held if it does not exist. But
+** the reason the mutex does not exist is because the build is not
+** using mutexes. And we do not want the assert() containing the
+** call to sqlite3_mutex_held() to fail, so a non-zero return is
+** the appropriate thing to do. ^The sqlite3_mutex_notheld()
+** interface should also return 1 when given a NULL pointer.
+*/
+#ifndef NDEBUG
+SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
+#endif
+
+/*
+** CAPI3REF: Mutex Types
+**
+** The [sqlite3_mutex_alloc()] interface takes a single argument
+** which is one of these integer constants.
+**
+** The set of static mutexes may change from one SQLite release to the
+** next. Applications that override the built-in mutex logic must be
+** prepared to accommodate additional static mutexes.
+*/
+#define SQLITE_MUTEX_FAST 0
+#define SQLITE_MUTEX_RECURSIVE 1
+#define SQLITE_MUTEX_STATIC_MASTER 2
+#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
+#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
+#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
+#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
+#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
+#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
+#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
+
+/*
+** CAPI3REF: Retrieve the mutex for a database connection
+**
+** ^This interface returns a pointer the [sqlite3_mutex] object that
+** serializes access to the [database connection] given in the argument
+** when the [threading mode] is Serialized.
+** ^If the [threading mode] is Single-thread or Multi-thread then this
+** routine returns a NULL pointer.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
+
+/*
+** CAPI3REF: Low-Level Control Of Database Files
+**
+** ^The [sqlite3_file_control()] interface makes a direct call to the
+** xFileControl method for the [sqlite3_io_methods] object associated
+** with a particular database identified by the second argument. ^The
+** name of the database is "main" for the main database or "temp" for the
+** TEMP database, or the name that appears after the AS keyword for
+** databases that are added using the [ATTACH] SQL command.
+** ^A NULL pointer can be used in place of "main" to refer to the
+** main database file.
+** ^The third and fourth parameters to this routine
+** are passed directly through to the second and third parameters of
+** the xFileControl method. ^The return value of the xFileControl
+** method becomes the return value of this routine.
+**
+** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
+** a pointer to the underlying [sqlite3_file] object to be written into
+** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER
+** case is a short-circuit path which does not actually invoke the
+** underlying sqlite3_io_methods.xFileControl method.
+**
+** ^If the second parameter (zDbName) does not match the name of any
+** open database file, then SQLITE_ERROR is returned. ^This error
+** code is not remembered and will not be recalled by [sqlite3_errcode()]
+** or [sqlite3_errmsg()]. The underlying xFileControl method might
+** also return SQLITE_ERROR. There is no way to distinguish between
+** an incorrect zDbName and an SQLITE_ERROR return from the underlying
+** xFileControl method.
+**
+** See also: [SQLITE_FCNTL_LOCKSTATE]
+*/
+SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
+
+/*
+** CAPI3REF: Testing Interface
+**
+** ^The sqlite3_test_control() interface is used to read out internal
+** state of SQLite and to inject faults into SQLite for testing
+** purposes. ^The first parameter is an operation code that determines
+** the number, meaning, and operation of all subsequent parameters.
+**
+** This interface is not for use by applications. It exists solely
+** for verifying the correct operation of the SQLite library. Depending
+** on how the SQLite library is compiled, this interface might not exist.
+**
+** The details of the operation codes, their meanings, the parameters
+** they take, and what they do are all subject to change without notice.
+** Unlike most of the SQLite API, this function is not guaranteed to
+** operate consistently from one release to the next.
+*/
+SQLITE_API int sqlite3_test_control(int op, ...);
+
+/*
+** CAPI3REF: Testing Interface Operation Codes
+**
+** These constants are the valid operation code parameters used
+** as the first argument to [sqlite3_test_control()].
+**
+** These parameters and their meanings are subject to change
+** without notice. These values are for testing purposes only.
+** Applications should not use any of these parameters or the
+** [sqlite3_test_control()] interface.
+*/
+#define SQLITE_TESTCTRL_FIRST 5
+#define SQLITE_TESTCTRL_PRNG_SAVE 5
+#define SQLITE_TESTCTRL_PRNG_RESTORE 6
+#define SQLITE_TESTCTRL_PRNG_RESET 7
+#define SQLITE_TESTCTRL_BITVEC_TEST 8
+#define SQLITE_TESTCTRL_FAULT_INSTALL 9
+#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
+#define SQLITE_TESTCTRL_PENDING_BYTE 11
+#define SQLITE_TESTCTRL_ASSERT 12
+#define SQLITE_TESTCTRL_ALWAYS 13
+#define SQLITE_TESTCTRL_RESERVE 14
+#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
+#define SQLITE_TESTCTRL_ISKEYWORD 16
+#define SQLITE_TESTCTRL_SCRATCHMALLOC 17
+#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
+#define SQLITE_TESTCTRL_EXPLAIN_STMT 19
+#define SQLITE_TESTCTRL_NEVER_CORRUPT 20
+#define SQLITE_TESTCTRL_VDBE_COVERAGE 21
+#define SQLITE_TESTCTRL_BYTEORDER 22
+#define SQLITE_TESTCTRL_LAST 22
+
+/*
+** CAPI3REF: SQLite Runtime Status
+**
+** ^This interface is used to retrieve runtime status information
+** about the performance of SQLite, and optionally to reset various
+** highwater marks. ^The first argument is an integer code for
+** the specific parameter to measure. ^(Recognized integer codes
+** are of the form [status parameters | SQLITE_STATUS_...].)^
+** ^The current value of the parameter is returned into *pCurrent.
+** ^The highest recorded value is returned in *pHighwater. ^If the
+** resetFlag is true, then the highest record value is reset after
+** *pHighwater is written. ^(Some parameters do not record the highest
+** value. For those parameters
+** nothing is written into *pHighwater and the resetFlag is ignored.)^
+** ^(Other parameters record only the highwater mark and not the current
+** value. For these latter parameters nothing is written into *pCurrent.)^
+**
+** ^The sqlite3_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
+** This routine is threadsafe but is not atomic. This routine can be
+** called while other threads are running the same or different SQLite
+** interfaces. However the values returned in *pCurrent and
+** *pHighwater reflect the status of SQLite at different points in time
+** and it is possible that another thread might change the parameter
+** in between the times when *pCurrent and *pHighwater are written.
+**
+** See also: [sqlite3_db_status()]
+*/
+SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
+
+
+/*
+** CAPI3REF: Status Parameters
+** KEYWORDS: {status parameters}
+**
+** These integer constants designate various run-time status parameters
+** that can be returned by [sqlite3_status()].
+**
+**
+** [[SQLITE_STATUS_MEMORY_USED]] ^(- SQLITE_STATUS_MEMORY_USED
+** - This parameter is the current amount of memory checked out
+** using [sqlite3_malloc()], either directly or indirectly. The
+** figure includes calls made to [sqlite3_malloc()] by the application
+** and internal memory usage by the SQLite library. Scratch memory
+** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
+** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
+** this parameter. The amount returned is the sum of the allocation
+** sizes as reported by the xSize method in [sqlite3_mem_methods].
)^
+**
+** [[SQLITE_STATUS_MALLOC_SIZE]] ^(- SQLITE_STATUS_MALLOC_SIZE
+** - This parameter records the largest memory allocation request
+** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
+** internal equivalents). Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.
+** The value written into the *pCurrent parameter is undefined.
)^
+**
+** [[SQLITE_STATUS_MALLOC_COUNT]] ^(- SQLITE_STATUS_MALLOC_COUNT
+** - This parameter records the number of separate memory allocations
+** currently checked out.
)^
+**
+** [[SQLITE_STATUS_PAGECACHE_USED]] ^(- SQLITE_STATUS_PAGECACHE_USED
+** - This parameter returns the number of pages used out of the
+** [pagecache memory allocator] that was configured using
+** [SQLITE_CONFIG_PAGECACHE]. The
+** value returned is in pages, not in bytes.
)^
+**
+** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
+** ^(- SQLITE_STATUS_PAGECACHE_OVERFLOW
+** - This parameter returns the number of bytes of page cache
+** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
+** buffer and where forced to overflow to [sqlite3_malloc()]. The
+** returned value includes allocations that overflowed because they
+** where too large (they were larger than the "sz" parameter to
+** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
+** no space was left in the page cache.
)^
+**
+** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(- SQLITE_STATUS_PAGECACHE_SIZE
+** - This parameter records the largest memory allocation request
+** handed to [pagecache memory allocator]. Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.
+** The value written into the *pCurrent parameter is undefined.
)^
+**
+** [[SQLITE_STATUS_SCRATCH_USED]] ^(- SQLITE_STATUS_SCRATCH_USED
+** - This parameter returns the number of allocations used out of the
+** [scratch memory allocator] configured using
+** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
+** in bytes. Since a single thread may only have one scratch allocation
+** outstanding at time, this parameter also reports the number of threads
+** using scratch memory at the same time.
)^
+**
+** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(- SQLITE_STATUS_SCRATCH_OVERFLOW
+** - This parameter returns the number of bytes of scratch memory
+** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
+** buffer and where forced to overflow to [sqlite3_malloc()]. The values
+** returned include overflows because the requested allocation was too
+** larger (that is, because the requested allocation was larger than the
+** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
+** slots were available.
+**
)^
+**
+** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(- SQLITE_STATUS_SCRATCH_SIZE
+** - This parameter records the largest memory allocation request
+** handed to [scratch memory allocator]. Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.
+** The value written into the *pCurrent parameter is undefined.
)^
+**
+** [[SQLITE_STATUS_PARSER_STACK]] ^(- SQLITE_STATUS_PARSER_STACK
+** - This parameter records the deepest parser stack. It is only
+** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].
)^
+**
+**
+** New status parameters may be added from time to time.
+*/
+#define SQLITE_STATUS_MEMORY_USED 0
+#define SQLITE_STATUS_PAGECACHE_USED 1
+#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
+#define SQLITE_STATUS_SCRATCH_USED 3
+#define SQLITE_STATUS_SCRATCH_OVERFLOW 4
+#define SQLITE_STATUS_MALLOC_SIZE 5
+#define SQLITE_STATUS_PARSER_STACK 6
+#define SQLITE_STATUS_PAGECACHE_SIZE 7
+#define SQLITE_STATUS_SCRATCH_SIZE 8
+#define SQLITE_STATUS_MALLOC_COUNT 9
+
+/*
+** CAPI3REF: Database Connection Status
+**
+** ^This interface is used to retrieve runtime status information
+** about a single [database connection]. ^The first argument is the
+** database connection object to be interrogated. ^The second argument
+** is an integer constant, taken from the set of
+** [SQLITE_DBSTATUS options], that
+** determines the parameter to interrogate. The set of
+** [SQLITE_DBSTATUS options] is likely
+** to grow in future releases of SQLite.
+**
+** ^The current value of the requested parameter is written into *pCur
+** and the highest instantaneous value is written into *pHiwtr. ^If
+** the resetFlg is true, then the highest instantaneous value is
+** reset back down to the current value.
+**
+** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
+** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
+*/
+SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for database connections
+** KEYWORDS: {SQLITE_DBSTATUS options}
+**
+** These constants are the available integer "verbs" that can be passed as
+** the second argument to the [sqlite3_db_status()] interface.
+**
+** New verbs may be added in future releases of SQLite. Existing verbs
+** might be discontinued. Applications should check the return code from
+** [sqlite3_db_status()] to make sure that the call worked.
+** The [sqlite3_db_status()] interface will return a non-zero error code
+** if a discontinued or unsupported verb is invoked.
+**
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(- SQLITE_DBSTATUS_LOOKASIDE_USED
+** - This parameter returns the number of lookaside memory slots currently
+** checked out.
)^
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(- SQLITE_DBSTATUS_LOOKASIDE_HIT
+** - This parameter returns the number malloc attempts that were
+** satisfied using lookaside memory. Only the high-water value is meaningful;
+** the current value is always zero.)^
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
+** ^(
- SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
+** - This parameter returns the number malloc attempts that might have
+** been satisfied using lookaside memory but failed due to the amount of
+** memory requested being larger than the lookaside slot size.
+** Only the high-water value is meaningful;
+** the current value is always zero.)^
+**
+** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
+** ^(
- SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
+** - This parameter returns the number malloc attempts that might have
+** been satisfied using lookaside memory but failed due to all lookaside
+** memory already being in use.
+** Only the high-water value is meaningful;
+** the current value is always zero.)^
+**
+** [[SQLITE_DBSTATUS_CACHE_USED]] ^(
- SQLITE_DBSTATUS_CACHE_USED
+** - This parameter returns the approximate number of of bytes of heap
+** memory used by all pager caches associated with the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
+**
+** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(
- SQLITE_DBSTATUS_SCHEMA_USED
+** - This parameter returns the approximate number of of bytes of heap
+** memory used to store the schema for all databases associated
+** with the connection - main, temp, and any [ATTACH]-ed databases.)^
+** ^The full amount of memory used by the schemas is reported, even if the
+** schema memory is shared with other database connections due to
+** [shared cache mode] being enabled.
+** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
+**
+** [[SQLITE_DBSTATUS_STMT_USED]] ^(
- SQLITE_DBSTATUS_STMT_USED
+** - This parameter returns the approximate number of of bytes of heap
+** and lookaside memory used by all prepared statements associated with
+** the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(- SQLITE_DBSTATUS_CACHE_HIT
+** - This parameter returns the number of pager cache hits that have
+** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
+** is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(- SQLITE_DBSTATUS_CACHE_MISS
+** - This parameter returns the number of pager cache misses that have
+** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
+** is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(- SQLITE_DBSTATUS_CACHE_WRITE
+** - This parameter returns the number of dirty cache entries that have
+** been written to disk. Specifically, the number of pages written to the
+** wal file in wal mode databases, or the number of pages written to the
+** database file in rollback mode databases. Any pages written as part of
+** transaction rollback or database recovery operations are not included.
+** If an IO or other error occurs while writing a page to disk, the effect
+** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
+** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
+**
+**
+** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(- SQLITE_DBSTATUS_DEFERRED_FKS
+** - This parameter returns zero for the current value if and only if
+** all foreign key constraints (deferred or immediate) have been
+** resolved.)^ ^The highwater mark is always 0.
+**
+**
+*/
+#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
+#define SQLITE_DBSTATUS_CACHE_USED 1
+#define SQLITE_DBSTATUS_SCHEMA_USED 2
+#define SQLITE_DBSTATUS_STMT_USED 3
+#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
+#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
+#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
+#define SQLITE_DBSTATUS_CACHE_HIT 7
+#define SQLITE_DBSTATUS_CACHE_MISS 8
+#define SQLITE_DBSTATUS_CACHE_WRITE 9
+#define SQLITE_DBSTATUS_DEFERRED_FKS 10
+#define SQLITE_DBSTATUS_MAX 10 /* Largest defined DBSTATUS */
+
+
+/*
+** CAPI3REF: Prepared Statement Status
+**
+** ^(Each prepared statement maintains various
+** [SQLITE_STMTSTATUS counters] that measure the number
+** of times it has performed specific operations.)^ These counters can
+** be used to monitor the performance characteristics of the prepared
+** statements. For example, if the number of table steps greatly exceeds
+** the number of table searches or result rows, that would tend to indicate
+** that the prepared statement is using a full table scan rather than
+** an index.
+**
+** ^(This interface is used to retrieve and reset counter values from
+** a [prepared statement]. The first argument is the prepared statement
+** object to be interrogated. The second argument
+** is an integer code for a specific [SQLITE_STMTSTATUS counter]
+** to be interrogated.)^
+** ^The current value of the requested counter is returned.
+** ^If the resetFlg is true, then the counter is reset to zero after this
+** interface call returns.
+**
+** See also: [sqlite3_status()] and [sqlite3_db_status()].
+*/
+SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for prepared statements
+** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
+**
+** These preprocessor macros define integer codes that name counter
+** values associated with the [sqlite3_stmt_status()] interface.
+** The meanings of the various counters are as follows:
+**
+**
+** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] - SQLITE_STMTSTATUS_FULLSCAN_STEP
+** - ^This is the number of times that SQLite has stepped forward in
+** a table as part of a full table scan. Large numbers for this counter
+** may indicate opportunities for performance improvement through
+** careful use of indices.
+**
+** [[SQLITE_STMTSTATUS_SORT]] - SQLITE_STMTSTATUS_SORT
+** - ^This is the number of sort operations that have occurred.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance through careful use of indices.
+**
+** [[SQLITE_STMTSTATUS_AUTOINDEX]] - SQLITE_STMTSTATUS_AUTOINDEX
+** - ^This is the number of rows inserted into transient indices that
+** were created automatically in order to help joins run faster.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance by adding permanent indices that do not
+** need to be reinitialized each time the statement is run.
+**
+** [[SQLITE_STMTSTATUS_VM_STEP]] - SQLITE_STMTSTATUS_VM_STEP
+** - ^This is the number of virtual machine operations executed
+** by the prepared statement if that number is less than or equal
+** to 2147483647. The number of virtual machine operations can be
+** used as a proxy for the total work done by the prepared statement.
+** If the number of virtual machine operations exceeds 2147483647
+** then the value returned by this statement status code is undefined.
+**
+**
+*/
+#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
+#define SQLITE_STMTSTATUS_SORT 2
+#define SQLITE_STMTSTATUS_AUTOINDEX 3
+#define SQLITE_STMTSTATUS_VM_STEP 4
+
+/*
+** CAPI3REF: Custom Page Cache Object
+**
+** The sqlite3_pcache type is opaque. It is implemented by
+** the pluggable module. The SQLite core has no knowledge of
+** its size or internal structure and never deals with the
+** sqlite3_pcache object except by holding and passing pointers
+** to the object.
+**
+** See [sqlite3_pcache_methods2] for additional information.
+*/
+typedef struct sqlite3_pcache sqlite3_pcache;
+
+/*
+** CAPI3REF: Custom Page Cache Object
+**
+** The sqlite3_pcache_page object represents a single page in the
+** page cache. The page cache will allocate instances of this
+** object. Various methods of the page cache use pointers to instances
+** of this object as parameters or as their return value.
+**
+** See [sqlite3_pcache_methods2] for additional information.
+*/
+typedef struct sqlite3_pcache_page sqlite3_pcache_page;
+struct sqlite3_pcache_page {
+ void *pBuf; /* The content of the page */
+ void *pExtra; /* Extra information associated with the page */
+};
+
+/*
+** CAPI3REF: Application Defined Page Cache.
+** KEYWORDS: {page cache}
+**
+** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
+** register an alternative page cache implementation by passing in an
+** instance of the sqlite3_pcache_methods2 structure.)^
+** In many applications, most of the heap memory allocated by
+** SQLite is used for the page cache.
+** By implementing a
+** custom page cache using this API, an application can better control
+** the amount of memory consumed by SQLite, the way in which
+** that memory is allocated and released, and the policies used to
+** determine exactly which parts of a database file are cached and for
+** how long.
+**
+** The alternative page cache mechanism is an
+** extreme measure that is only needed by the most demanding applications.
+** The built-in page cache is recommended for most uses.
+**
+** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
+** internal buffer by SQLite within the call to [sqlite3_config]. Hence
+** the application may discard the parameter after the call to
+** [sqlite3_config()] returns.)^
+**
+** [[the xInit() page cache method]]
+** ^(The xInit() method is called once for each effective
+** call to [sqlite3_initialize()])^
+** (usually only once during the lifetime of the process). ^(The xInit()
+** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
+** The intent of the xInit() method is to set up global data structures
+** required by the custom page cache implementation.
+** ^(If the xInit() method is NULL, then the
+** built-in default page cache is used instead of the application defined
+** page cache.)^
+**
+** [[the xShutdown() page cache method]]
+** ^The xShutdown() method is called by [sqlite3_shutdown()].
+** It can be used to clean up
+** any outstanding resources before process shutdown, if required.
+** ^The xShutdown() method may be NULL.
+**
+** ^SQLite automatically serializes calls to the xInit method,
+** so the xInit method need not be threadsafe. ^The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either. All other methods must be threadsafe
+** in multithreaded applications.
+**
+** ^SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+**
+** [[the xCreate() page cache methods]]
+** ^SQLite invokes the xCreate() method to construct a new cache instance.
+** SQLite will typically create one cache instance for each open database file,
+** though this is not guaranteed. ^The
+** first parameter, szPage, is the size in bytes of the pages that must
+** be allocated by the cache. ^szPage will always a power of two. ^The
+** second parameter szExtra is a number of bytes of extra storage
+** associated with each page cache entry. ^The szExtra parameter will
+** a number less than 250. SQLite will use the
+** extra szExtra bytes on each page to store metadata about the underlying
+** database page on disk. The value passed into szExtra depends
+** on the SQLite version, the target platform, and how SQLite was compiled.
+** ^The third argument to xCreate(), bPurgeable, is true if the cache being
+** created will be used to cache database pages of a file stored on disk, or
+** false if it is used for an in-memory database. The cache implementation
+** does not have to do anything special based with the value of bPurgeable;
+** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
+** never invoke xUnpin() except to deliberately delete a page.
+** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
+** false will always have the "discard" flag set to true.
+** ^Hence, a cache created with bPurgeable false will
+** never contain any unpinned pages.
+**
+** [[the xCachesize() page cache method]]
+** ^(The xCachesize() method may be called at any time by SQLite to set the
+** suggested maximum cache-size (number of pages stored by) the cache
+** instance passed as the first argument. This is the value configured using
+** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
+** parameter, the implementation is not required to do anything with this
+** value; it is advisory only.
+**
+** [[the xPagecount() page cache methods]]
+** The xPagecount() method must return the number of pages currently
+** stored in the cache, both pinned and unpinned.
+**
+** [[the xFetch() page cache methods]]
+** The xFetch() method locates a page in the cache and returns a pointer to
+** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
+** The pBuf element of the returned sqlite3_pcache_page object will be a
+** pointer to a buffer of szPage bytes used to store the content of a
+** single database page. The pExtra element of sqlite3_pcache_page will be
+** a pointer to the szExtra bytes of extra storage that SQLite has requested
+** for each entry in the page cache.
+**
+** The page to be fetched is determined by the key. ^The minimum key value
+** is 1. After it has been retrieved using xFetch, the page is considered
+** to be "pinned".
+**
+** If the requested page is already in the page cache, then the page cache
+** implementation must return a pointer to the page buffer with its content
+** intact. If the requested page is not already in the cache, then the
+** cache implementation should use the value of the createFlag
+** parameter to help it determined what action to take:
+**
+**
+** createFlag | Behavior when page is not already in cache
+** |
---|
0 | Do not allocate a new page. Return NULL.
+** |
1 | Allocate a new page if it easy and convenient to do so.
+** Otherwise return NULL.
+** |
2 | Make every effort to allocate a new page. Only return
+** NULL if allocating a new page is effectively impossible.
+** |
+**
+** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
+** will only use a createFlag of 2 after a prior call with a createFlag of 1
+** failed.)^ In between the to xFetch() calls, SQLite may
+** attempt to unpin one or more cache pages by spilling the content of
+** pinned pages to disk and synching the operating system disk cache.
+**
+** [[the xUnpin() page cache method]]
+** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
+** as its second argument. If the third parameter, discard, is non-zero,
+** then the page must be evicted from the cache.
+** ^If the discard parameter is
+** zero, then the page may be discarded or retained at the discretion of
+** page cache implementation. ^The page cache implementation
+** may choose to evict unpinned pages at any time.
+**
+** The cache must not perform any reference counting. A single
+** call to xUnpin() unpins the page regardless of the number of prior calls
+** to xFetch().
+**
+** [[the xRekey() page cache methods]]
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument. If the cache
+** previously contains an entry associated with newKey, it must be
+** discarded. ^Any prior cache entry associated with newKey is guaranteed not
+** to be pinned.
+**
+** When SQLite calls the xTruncate() method, the cache must discard all
+** existing cache entries with page numbers (keys) greater than or equal
+** to the value of the iLimit parameter passed to xTruncate(). If any
+** of these pages are pinned, they are implicitly unpinned, meaning that
+** they can be safely discarded.
+**
+** [[the xDestroy() page cache method]]
+** ^The xDestroy() method is used to delete a cache allocated by xCreate().
+** All resources associated with the specified cache should be freed. ^After
+** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
+** handle invalid, and will not use it with any other sqlite3_pcache_methods2
+** functions.
+**
+** [[the xShrink() page cache method]]
+** ^SQLite invokes the xShrink() method when it wants the page cache to
+** free up as much of heap memory as possible. The page cache implementation
+** is not obligated to free any memory, but well-behaved implementations should
+** do their best.
+*/
+typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
+struct sqlite3_pcache_methods2 {
+ int iVersion;
+ void *pArg;
+ int (*xInit)(void*);
+ void (*xShutdown)(void*);
+ sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
+ void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+ int (*xPagecount)(sqlite3_pcache*);
+ sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+ void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
+ void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
+ unsigned oldKey, unsigned newKey);
+ void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+ void (*xDestroy)(sqlite3_pcache*);
+ void (*xShrink)(sqlite3_pcache*);
+};
+
+/*
+** This is the obsolete pcache_methods object that has now been replaced
+** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
+** retained in the header file for backwards compatibility only.
+*/
+typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
+struct sqlite3_pcache_methods {
+ void *pArg;
+ int (*xInit)(void*);
+ void (*xShutdown)(void*);
+ sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
+ void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+ int (*xPagecount)(sqlite3_pcache*);
+ void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+ void (*xUnpin)(sqlite3_pcache*, void*, int discard);
+ void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
+ void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+ void (*xDestroy)(sqlite3_pcache*);
+};
+
+
+/*
+** CAPI3REF: Online Backup Object
+**
+** The sqlite3_backup object records state information about an ongoing
+** online backup operation. ^The sqlite3_backup object is created by
+** a call to [sqlite3_backup_init()] and is destroyed by a call to
+** [sqlite3_backup_finish()].
+**
+** See Also: [Using the SQLite Online Backup API]
+*/
+typedef struct sqlite3_backup sqlite3_backup;
+
+/*
+** CAPI3REF: Online Backup API.
+**
+** The backup API copies the content of one database into another.
+** It is useful either for creating backups of databases or
+** for copying in-memory databases to or from persistent files.
+**
+** See Also: [Using the SQLite Online Backup API]
+**
+** ^SQLite holds a write transaction open on the destination database file
+** for the duration of the backup operation.
+** ^The source database is read-locked only while it is being read;
+** it is not locked continuously for the entire backup operation.
+** ^Thus, the backup may be performed on a live source database without
+** preventing other database connections from
+** reading or writing to the source database while the backup is underway.
+**
+** ^(To perform a backup operation:
+**
+** - sqlite3_backup_init() is called once to initialize the
+** backup,
+**
- sqlite3_backup_step() is called one or more times to transfer
+** the data between the two databases, and finally
+**
- sqlite3_backup_finish() is called to release all resources
+** associated with the backup operation.
+**
)^
+** There should be exactly one call to sqlite3_backup_finish() for each
+** successful call to sqlite3_backup_init().
+**
+** [[sqlite3_backup_init()]] sqlite3_backup_init()
+**
+** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
+** [database connection] associated with the destination database
+** and the database name, respectively.
+** ^The database name is "main" for the main database, "temp" for the
+** temporary database, or the name specified after the AS keyword in
+** an [ATTACH] statement for an attached database.
+** ^The S and M arguments passed to
+** sqlite3_backup_init(D,N,S,M) identify the [database connection]
+** and database name of the source database, respectively.
+** ^The source and destination [database connections] (parameters S and D)
+** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
+** an error.
+**
+** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
+** returned and an error code and error message are stored in the
+** destination [database connection] D.
+** ^The error code and message for the failed call to sqlite3_backup_init()
+** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
+** [sqlite3_errmsg16()] functions.
+** ^A successful call to sqlite3_backup_init() returns a pointer to an
+** [sqlite3_backup] object.
+** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
+** sqlite3_backup_finish() functions to perform the specified backup
+** operation.
+**
+** [[sqlite3_backup_step()]] sqlite3_backup_step()
+**
+** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
+** the source and destination databases specified by [sqlite3_backup] object B.
+** ^If N is negative, all remaining source pages are copied.
+** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
+** are still more pages to be copied, then the function returns [SQLITE_OK].
+** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
+** from source to destination, then it returns [SQLITE_DONE].
+** ^If an error occurs while running sqlite3_backup_step(B,N),
+** then an [error code] is returned. ^As well as [SQLITE_OK] and
+** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
+** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
+**
+** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
+**
+** - the destination database was opened read-only, or
+**
- the destination database is using write-ahead-log journaling
+** and the destination and source page sizes differ, or
+**
- the destination database is an in-memory database and the
+** destination and source page sizes differ.
+**
)^
+**
+** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
+** the [sqlite3_busy_handler | busy-handler function]
+** is invoked (if one is specified). ^If the
+** busy-handler returns non-zero before the lock is available, then
+** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
+** sqlite3_backup_step() can be retried later. ^If the source
+** [database connection]
+** is being used to write to the source database when sqlite3_backup_step()
+** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
+** case the call to sqlite3_backup_step() can be retried later on. ^(If
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
+** [SQLITE_READONLY] is returned, then
+** there is no point in retrying the call to sqlite3_backup_step(). These
+** errors are considered fatal.)^ The application must accept
+** that the backup operation has failed and pass the backup operation handle
+** to the sqlite3_backup_finish() to release associated resources.
+**
+** ^The first call to sqlite3_backup_step() obtains an exclusive lock
+** on the destination file. ^The exclusive lock is not released until either
+** sqlite3_backup_finish() is called or the backup operation is complete
+** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
+** sqlite3_backup_step() obtains a [shared lock] on the source database that
+** lasts for the duration of the sqlite3_backup_step() call.
+** ^Because the source database is not locked between calls to
+** sqlite3_backup_step(), the source database may be modified mid-way
+** through the backup process. ^If the source database is modified by an
+** external process or via a database connection other than the one being
+** used by the backup operation, then the backup will be automatically
+** restarted by the next call to sqlite3_backup_step(). ^If the source
+** database is modified by the using the same database connection as is used
+** by the backup operation, then the backup database is automatically
+** updated at the same time.
+**
+** [[sqlite3_backup_finish()]] sqlite3_backup_finish()
+**
+** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
+** application wishes to abandon the backup operation, the application
+** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
+** ^The sqlite3_backup_finish() interfaces releases all
+** resources associated with the [sqlite3_backup] object.
+** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
+** active write-transaction on the destination database is rolled back.
+** The [sqlite3_backup] object is invalid
+** and may not be used following a call to sqlite3_backup_finish().
+**
+** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
+** sqlite3_backup_step() errors occurred, regardless or whether or not
+** sqlite3_backup_step() completed.
+** ^If an out-of-memory condition or IO error occurred during any prior
+** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
+** sqlite3_backup_finish() returns the corresponding [error code].
+**
+** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
+** is not a permanent error and does not affect the return value of
+** sqlite3_backup_finish().
+**
+** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]]
+** sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+**
+** ^Each call to sqlite3_backup_step() sets two values inside
+** the [sqlite3_backup] object: the number of pages still to be backed
+** up and the total number of pages in the source database file.
+** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
+** retrieve these two values, respectively.
+**
+** ^The values returned by these functions are only updated by
+** sqlite3_backup_step(). ^If the source database is modified during a backup
+** operation, then the values are not updated to account for any extra
+** pages that need to be updated or the size of the source database file
+** changing.
+**
+** Concurrent Usage of Database Handles
+**
+** ^The source [database connection] may be used by the application for other
+** purposes while a backup operation is underway or being initialized.
+** ^If SQLite is compiled and configured to support threadsafe database
+** connections, then the source database connection may be used concurrently
+** from within other threads.
+**
+** However, the application must guarantee that the destination
+** [database connection] is not passed to any other API (by any thread) after
+** sqlite3_backup_init() is called and before the corresponding call to
+** sqlite3_backup_finish(). SQLite does not currently check to see
+** if the application incorrectly accesses the destination [database connection]
+** and so no error code is reported, but the operations may malfunction
+** nevertheless. Use of the destination database connection while a
+** backup is in progress might also also cause a mutex deadlock.
+**
+** If running in [shared cache mode], the application must
+** guarantee that the shared cache used by the destination database
+** is not accessed while the backup is running. In practice this means
+** that the application must guarantee that the disk file being
+** backed up to is not accessed by any connection within the process,
+** not just the specific connection that was passed to sqlite3_backup_init().
+**
+** The [sqlite3_backup] object itself is partially threadsafe. Multiple
+** threads may safely make multiple concurrent calls to sqlite3_backup_step().
+** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+** APIs are not strictly speaking threadsafe. If they are invoked at the
+** same time as another thread is invoking sqlite3_backup_step() it is
+** possible that they return invalid values.
+*/
+SQLITE_API sqlite3_backup *sqlite3_backup_init(
+ sqlite3 *pDest, /* Destination database handle */
+ const char *zDestName, /* Destination database name */
+ sqlite3 *pSource, /* Source database handle */
+ const char *zSourceName /* Source database name */
+);
+SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
+SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
+
+/*
+** CAPI3REF: Unlock Notification
+**
+** ^When running in shared-cache mode, a database operation may fail with
+** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
+** individual tables within the shared-cache cannot be obtained. See
+** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
+** ^This API may be used to register a callback that SQLite will invoke
+** when the connection currently holding the required lock relinquishes it.
+** ^This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
+**
+** See Also: [Using the SQLite Unlock Notification Feature].
+**
+** ^Shared-cache locks are released when a database connection concludes
+** its current transaction, either by committing it or rolling it back.
+**
+** ^When a connection (known as the blocked connection) fails to obtain a
+** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
+** identity of the database connection (the blocking connection) that
+** has locked the required resource is stored internally. ^After an
+** application receives an SQLITE_LOCKED error, it may call the
+** sqlite3_unlock_notify() method with the blocked connection handle as
+** the first argument to register for a callback that will be invoked
+** when the blocking connections current transaction is concluded. ^The
+** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
+** call that concludes the blocking connections transaction.
+**
+** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
+** there is a chance that the blocking connection will have already
+** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
+** If this happens, then the specified callback is invoked immediately,
+** from within the call to sqlite3_unlock_notify().)^
+**
+** ^If the blocked connection is attempting to obtain a write-lock on a
+** shared-cache table, and more than one other connection currently holds
+** a read-lock on the same table, then SQLite arbitrarily selects one of
+** the other connections to use as the blocking connection.
+**
+** ^(There may be at most one unlock-notify callback registered by a
+** blocked connection. If sqlite3_unlock_notify() is called when the
+** blocked connection already has a registered unlock-notify callback,
+** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
+** called with a NULL pointer as its second argument, then any existing
+** unlock-notify callback is canceled. ^The blocked connections
+** unlock-notify callback may also be canceled by closing the blocked
+** connection using [sqlite3_close()].
+**
+** The unlock-notify callback is not reentrant. If an application invokes
+** any sqlite3_xxx API functions from within an unlock-notify callback, a
+** crash or deadlock may be the result.
+**
+** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
+** returns SQLITE_OK.
+**
+** Callback Invocation Details
+**
+** When an unlock-notify callback is registered, the application provides a
+** single void* pointer that is passed to the callback when it is invoked.
+** However, the signature of the callback function allows SQLite to pass
+** it an array of void* context pointers. The first argument passed to
+** an unlock-notify callback is a pointer to an array of void* pointers,
+** and the second is the number of entries in the array.
+**
+** When a blocking connections transaction is concluded, there may be
+** more than one blocked connection that has registered for an unlock-notify
+** callback. ^If two or more such blocked connections have specified the
+** same callback function, then instead of invoking the callback function
+** multiple times, it is invoked once with the set of void* context pointers
+** specified by the blocked connections bundled together into an array.
+** This gives the application an opportunity to prioritize any actions
+** related to the set of unblocked database connections.
+**
+** Deadlock Detection
+**
+** Assuming that after registering for an unlock-notify callback a
+** database waits for the callback to be issued before taking any further
+** action (a reasonable assumption), then using this API may cause the
+** application to deadlock. For example, if connection X is waiting for
+** connection Y's transaction to be concluded, and similarly connection
+** Y is waiting on connection X's transaction, then neither connection
+** will proceed and the system may remain deadlocked indefinitely.
+**
+** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
+** detection. ^If a given call to sqlite3_unlock_notify() would put the
+** system in a deadlocked state, then SQLITE_LOCKED is returned and no
+** unlock-notify callback is registered. The system is said to be in
+** a deadlocked state if connection A has registered for an unlock-notify
+** callback on the conclusion of connection B's transaction, and connection
+** B has itself registered for an unlock-notify callback when connection
+** A's transaction is concluded. ^Indirect deadlock is also detected, so
+** the system is also considered to be deadlocked if connection B has
+** registered for an unlock-notify callback on the conclusion of connection
+** C's transaction, where connection C is waiting on connection A. ^Any
+** number of levels of indirection are allowed.
+**
+** The "DROP TABLE" Exception
+**
+** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
+** always appropriate to call sqlite3_unlock_notify(). There is however,
+** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
+** SQLite checks if there are any currently executing SELECT statements
+** that belong to the same connection. If there are, SQLITE_LOCKED is
+** returned. In this case there is no "blocking connection", so invoking
+** sqlite3_unlock_notify() results in the unlock-notify callback being
+** invoked immediately. If the application then re-attempts the "DROP TABLE"
+** or "DROP INDEX" query, an infinite loop might be the result.
+**
+** One way around this problem is to check the extended error code returned
+** by an sqlite3_step() call. ^(If there is a blocking connection, then the
+** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
+** the special "DROP TABLE/INDEX" case, the extended error code is just
+** SQLITE_LOCKED.)^
+*/
+SQLITE_API int sqlite3_unlock_notify(
+ sqlite3 *pBlocked, /* Waiting connection */
+ void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
+ void *pNotifyArg /* Argument to pass to xNotify */
+);
+
+
+/*
+** CAPI3REF: String Comparison
+**
+** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
+** and extensions to compare the contents of two buffers containing UTF-8
+** strings in a case-independent fashion, using the same definition of "case
+** independence" that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_stricmp(const char *, const char *);
+SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
+
+/*
+** CAPI3REF: String Globbing
+*
+** ^The [sqlite3_strglob(P,X)] interface returns zero if string X matches
+** the glob pattern P, and it returns non-zero if string X does not match
+** the glob pattern P. ^The definition of glob pattern matching used in
+** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
+** SQL dialect used by SQLite. ^The sqlite3_strglob(P,X) function is case
+** sensitive.
+**
+** Note that this routine returns zero on a match and non-zero if the strings
+** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
+*/
+SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
+
+/*
+** CAPI3REF: Error Logging Interface
+**
+** ^The [sqlite3_log()] interface writes a message into the [error log]
+** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
+** ^If logging is enabled, the zFormat string and subsequent arguments are
+** used with [sqlite3_snprintf()] to generate the final output string.
+**
+** The sqlite3_log() interface is intended for use by extensions such as
+** virtual tables, collating functions, and SQL functions. While there is
+** nothing to prevent an application from calling sqlite3_log(), doing so
+** is considered bad form.
+**
+** The zFormat string must not be NULL.
+**
+** To avoid deadlocks and other threading problems, the sqlite3_log() routine
+** will not use dynamically allocated memory. The log message is stored in
+** a fixed-length buffer on the stack. If the log message is longer than
+** a few hundred characters, it will be truncated to the length of the
+** buffer.
+*/
+SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
+
+/*
+** CAPI3REF: Write-Ahead Log Commit Hook
+**
+** ^The [sqlite3_wal_hook()] function is used to register a callback that
+** will be invoked each time a database connection commits data to a
+** [write-ahead log] (i.e. whenever a transaction is committed in
+** [journal_mode | journal_mode=WAL mode]).
+**
+** ^The callback is invoked by SQLite after the commit has taken place and
+** the associated write-lock on the database released, so the implementation
+** may read, write or [checkpoint] the database as required.
+**
+** ^The first parameter passed to the callback function when it is invoked
+** is a copy of the third parameter passed to sqlite3_wal_hook() when
+** registering the callback. ^The second is a copy of the database handle.
+** ^The third parameter is the name of the database that was written to -
+** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
+** is the number of pages currently in the write-ahead log file,
+** including those that were just committed.
+**
+** The callback function should normally return [SQLITE_OK]. ^If an error
+** code is returned, that error will propagate back up through the
+** SQLite code base to cause the statement that provoked the callback
+** to report an error, though the commit will have still occurred. If the
+** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
+** that does not correspond to any valid SQLite error code, the results
+** are undefined.
+**
+** A single database handle may have at most a single write-ahead log callback
+** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
+** previously registered write-ahead log callback. ^Note that the
+** [sqlite3_wal_autocheckpoint()] interface and the
+** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
+** those overwrite any prior [sqlite3_wal_hook()] settings.
+*/
+SQLITE_API void *sqlite3_wal_hook(
+ sqlite3*,
+ int(*)(void *,sqlite3*,const char*,int),
+ void*
+);
+
+/*
+** CAPI3REF: Configure an auto-checkpoint
+**
+** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
+** [sqlite3_wal_hook()] that causes any database on [database connection] D
+** to automatically [checkpoint]
+** after committing a transaction if there are N or
+** more frames in the [write-ahead log] file. ^Passing zero or
+** a negative value as the nFrame parameter disables automatic
+** checkpoints entirely.
+**
+** ^The callback registered by this function replaces any existing callback
+** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
+** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
+** configured by this function.
+**
+** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
+** from SQL.
+**
+** ^Every new [database connection] defaults to having the auto-checkpoint
+** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
+** pages. The use of this interface
+** is only necessary if the default setting is found to be suboptimal
+** for a particular application.
+*/
+SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
+
+/*
+** CAPI3REF: Checkpoint a database
+**
+** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
+** on [database connection] D to be [checkpointed]. ^If X is NULL or an
+** empty string, then a checkpoint is run on all databases of
+** connection D. ^If the database connection D is not in
+** [WAL | write-ahead log mode] then this interface is a harmless no-op.
+**
+** ^The [wal_checkpoint pragma] can be used to invoke this interface
+** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
+** [wal_autocheckpoint pragma] can be used to cause this interface to be
+** run whenever the WAL reaches a certain size threshold.
+**
+** See also: [sqlite3_wal_checkpoint_v2()]
+*/
+SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
+
+/*
+** CAPI3REF: Checkpoint a database
+**
+** Run a checkpoint operation on WAL database zDb attached to database
+** handle db. The specific operation is determined by the value of the
+** eMode parameter:
+**
+**
+** - SQLITE_CHECKPOINT_PASSIVE
-
+** Checkpoint as many frames as possible without waiting for any database
+** readers or writers to finish. Sync the db file if all frames in the log
+** are checkpointed. This mode is the same as calling
+** sqlite3_wal_checkpoint(). The busy-handler callback is never invoked.
+**
+**
- SQLITE_CHECKPOINT_FULL
-
+** This mode blocks (calls the busy-handler callback) until there is no
+** database writer and all readers are reading from the most recent database
+** snapshot. It then checkpoints all frames in the log file and syncs the
+** database file. This call blocks database writers while it is running,
+** but not database readers.
+**
+**
- SQLITE_CHECKPOINT_RESTART
-
+** This mode works the same way as SQLITE_CHECKPOINT_FULL, except after
+** checkpointing the log file it blocks (calls the busy-handler callback)
+** until all readers are reading from the database file only. This ensures
+** that the next client to write to the database file restarts the log file
+** from the beginning. This call blocks database writers while it is running,
+** but not database readers.
+**
+**
+** If pnLog is not NULL, then *pnLog is set to the total number of frames in
+** the log file before returning. If pnCkpt is not NULL, then *pnCkpt is set to
+** the total number of checkpointed frames (including any that were already
+** checkpointed when this function is called). *pnLog and *pnCkpt may be
+** populated even if sqlite3_wal_checkpoint_v2() returns other than SQLITE_OK.
+** If no values are available because of an error, they are both set to -1
+** before returning to communicate this to the caller.
+**
+** All calls obtain an exclusive "checkpoint" lock on the database file. If
+** any other process is running a checkpoint operation at the same time, the
+** lock cannot be obtained and SQLITE_BUSY is returned. Even if there is a
+** busy-handler configured, it will not be invoked in this case.
+**
+** The SQLITE_CHECKPOINT_FULL and RESTART modes also obtain the exclusive
+** "writer" lock on the database file. If the writer lock cannot be obtained
+** immediately, and a busy-handler is configured, it is invoked and the writer
+** lock retried until either the busy-handler returns 0 or the lock is
+** successfully obtained. The busy-handler is also invoked while waiting for
+** database readers as described above. If the busy-handler returns 0 before
+** the writer lock is obtained or while waiting for database readers, the
+** checkpoint operation proceeds from that point in the same way as
+** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
+** without blocking any further. SQLITE_BUSY is returned in this case.
+**
+** If parameter zDb is NULL or points to a zero length string, then the
+** specified operation is attempted on all WAL databases. In this case the
+** values written to output parameters *pnLog and *pnCkpt are undefined. If
+** an SQLITE_BUSY error is encountered when processing one or more of the
+** attached WAL databases, the operation is still attempted on any remaining
+** attached databases and SQLITE_BUSY is returned to the caller. If any other
+** error occurs while processing an attached database, processing is abandoned
+** and the error code returned to the caller immediately. If no error
+** (SQLITE_BUSY or otherwise) is encountered while processing the attached
+** databases, SQLITE_OK is returned.
+**
+** If database zDb is the name of an attached database that is not in WAL
+** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. If
+** zDb is not NULL (or a zero length string) and is not the name of any
+** attached database, SQLITE_ERROR is returned to the caller.
+*/
+SQLITE_API int sqlite3_wal_checkpoint_v2(
+ sqlite3 *db, /* Database handle */
+ const char *zDb, /* Name of attached database (or NULL) */
+ int eMode, /* SQLITE_CHECKPOINT_* value */
+ int *pnLog, /* OUT: Size of WAL log in frames */
+ int *pnCkpt /* OUT: Total number of frames checkpointed */
+);
+
+/*
+** CAPI3REF: Checkpoint operation parameters
+**
+** These constants can be used as the 3rd parameter to
+** [sqlite3_wal_checkpoint_v2()]. See the [sqlite3_wal_checkpoint_v2()]
+** documentation for additional information about the meaning and use of
+** each of these values.
+*/
+#define SQLITE_CHECKPOINT_PASSIVE 0
+#define SQLITE_CHECKPOINT_FULL 1
+#define SQLITE_CHECKPOINT_RESTART 2
+
+/*
+** CAPI3REF: Virtual Table Interface Configuration
+**
+** This function may be called by either the [xConnect] or [xCreate] method
+** of a [virtual table] implementation to configure
+** various facets of the virtual table interface.
+**
+** If this interface is invoked outside the context of an xConnect or
+** xCreate virtual table method then the behavior is undefined.
+**
+** At present, there is only one option that may be configured using
+** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
+** may be added in the future.
+*/
+SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Virtual Table Configuration Options
+**
+** These macros define the various options to the
+** [sqlite3_vtab_config()] interface that [virtual table] implementations
+** can use to customize and optimize their behavior.
+**
+**
+** - SQLITE_VTAB_CONSTRAINT_SUPPORT
+**
- Calls of the form
+** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
+** where X is an integer. If X is zero, then the [virtual table] whose
+** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
+** support constraints. In this configuration (which is the default) if
+** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
+** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
+** specified as part of the users SQL statement, regardless of the actual
+** ON CONFLICT mode specified.
+**
+** If X is non-zero, then the virtual table implementation guarantees
+** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
+** any modifications to internal or persistent data structures have been made.
+** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
+** is able to roll back a statement or database transaction, and abandon
+** or continue processing the current SQL statement as appropriate.
+** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
+** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
+** had been ABORT.
+**
+** Virtual table implementations that are required to handle OR REPLACE
+** must do so within the [xUpdate] method. If a call to the
+** [sqlite3_vtab_on_conflict()] function indicates that the current ON
+** CONFLICT policy is REPLACE, the virtual table implementation should
+** silently replace the appropriate rows within the xUpdate callback and
+** return SQLITE_OK. Or, if this is not possible, it may return
+** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
+** constraint handling.
+**
+*/
+#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
+
+/*
+** CAPI3REF: Determine The Virtual Table Conflict Policy
+**
+** This function may only be called from within a call to the [xUpdate] method
+** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
+** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
+** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
+** of the SQL statement that triggered the call to the [xUpdate] method of the
+** [virtual table].
+*/
+SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
+
+/*
+** CAPI3REF: Conflict resolution modes
+**
+** These constants are returned by [sqlite3_vtab_on_conflict()] to
+** inform a [virtual table] implementation what the [ON CONFLICT] mode
+** is for the SQL statement being evaluated.
+**
+** Note that the [SQLITE_IGNORE] constant is also used as a potential
+** return value from the [sqlite3_set_authorizer()] callback and that
+** [SQLITE_ABORT] is also a [result code].
+*/
+#define SQLITE_ROLLBACK 1
+/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
+#define SQLITE_FAIL 3
+/* #define SQLITE_ABORT 4 // Also an error code */
+#define SQLITE_REPLACE 5
+
+
+
+/*
+** Undo the hack that converts floating point types to integer for
+** builds on processors without floating point support.
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# undef double
+#endif
+
+#if 0
+} /* End of the 'extern "C"' block */
+#endif
+#endif /* _SQLITE3_H_ */
+
+/*
+** 2010 August 30
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+*/
+
+#ifndef _SQLITE3RTREE_H_
+#define _SQLITE3RTREE_H_
+
+
+#if 0
+extern "C" {
+#endif
+
+typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
+typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
+
+/* The double-precision datatype used by RTree depends on the
+** SQLITE_RTREE_INT_ONLY compile-time option.
+*/
+#ifdef SQLITE_RTREE_INT_ONLY
+ typedef sqlite3_int64 sqlite3_rtree_dbl;
+#else
+ typedef double sqlite3_rtree_dbl;
+#endif
+
+/*
+** Register a geometry callback named zGeom that can be used as part of an
+** R-Tree geometry query as follows:
+**
+** SELECT ... FROM WHERE MATCH $zGeom(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+ sqlite3 *db,
+ const char *zGeom,
+ int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
+ void *pContext
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the first
+** argument to callbacks registered using rtree_geometry_callback().
+*/
+struct sqlite3_rtree_geometry {
+ void *pContext; /* Copy of pContext passed to s_r_g_c() */
+ int nParam; /* Size of array aParam[] */
+ sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */
+ void *pUser; /* Callback implementation user data */
+ void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
+};
+
+/*
+** Register a 2nd-generation geometry callback named zScore that can be
+** used as part of an R-Tree geometry query as follows:
+**
+** SELECT ... FROM WHERE MATCH $zQueryFunc(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_query_callback(
+ sqlite3 *db,
+ const char *zQueryFunc,
+ int (*xQueryFunc)(sqlite3_rtree_query_info*),
+ void *pContext,
+ void (*xDestructor)(void*)
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the
+** argument to scored geometry callback registered using
+** sqlite3_rtree_query_callback().
+**
+** Note that the first 5 fields of this structure are identical to
+** sqlite3_rtree_geometry. This structure is a subclass of
+** sqlite3_rtree_geometry.
+*/
+struct sqlite3_rtree_query_info {
+ void *pContext; /* pContext from when function registered */
+ int nParam; /* Number of function parameters */
+ sqlite3_rtree_dbl *aParam; /* value of function parameters */
+ void *pUser; /* callback can use this, if desired */
+ void (*xDelUser)(void*); /* function to free pUser */
+ sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */
+ unsigned int *anQueue; /* Number of pending entries in the queue */
+ int nCoord; /* Number of coordinates */
+ int iLevel; /* Level of current node or entry */
+ int mxLevel; /* The largest iLevel value in the tree */
+ sqlite3_int64 iRowid; /* Rowid for current entry */
+ sqlite3_rtree_dbl rParentScore; /* Score of parent node */
+ int eParentWithin; /* Visibility of parent node */
+ int eWithin; /* OUT: Visiblity */
+ sqlite3_rtree_dbl rScore; /* OUT: Write the score here */
+};
+
+/*
+** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
+*/
+#define NOT_WITHIN 0 /* Object completely outside of query region */
+#define PARTLY_WITHIN 1 /* Object partially overlaps query region */
+#define FULLY_WITHIN 2 /* Object fully contained within query region */
+
+
+#if 0
+} /* end of the 'extern "C"' block */
+#endif
+
+#endif /* ifndef _SQLITE3RTREE_H_ */
+
+
+/************** End of sqlite3.h *********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+
+/*
+** Include the configuration header output by 'configure' if we're using the
+** autoconf-based build
+*/
+#ifdef _HAVE_SQLITE_CONFIG_H
+#include "config.h"
+#endif
+
+/************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/
+/************** Begin file sqliteLimit.h *************************************/
+/*
+** 2007 May 7
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file defines various limits of what SQLite can process.
+*/
+
+/*
+** The maximum length of a TEXT or BLOB in bytes. This also
+** limits the size of a row in a table or index.
+**
+** The hard limit is the ability of a 32-bit signed integer
+** to count the size: 2^31-1 or 2147483647.
+*/
+#ifndef SQLITE_MAX_LENGTH
+# define SQLITE_MAX_LENGTH 1000000000
+#endif
+
+/*
+** This is the maximum number of
+**
+** * Columns in a table
+** * Columns in an index
+** * Columns in a view
+** * Terms in the SET clause of an UPDATE statement
+** * Terms in the result set of a SELECT statement
+** * Terms in the GROUP BY or ORDER BY clauses of a SELECT statement.
+** * Terms in the VALUES clause of an INSERT statement
+**
+** The hard upper limit here is 32676. Most database people will
+** tell you that in a well-normalized database, you usually should
+** not have more than a dozen or so columns in any table. And if
+** that is the case, there is no point in having more than a few
+** dozen values in any of the other situations described above.
+*/
+#ifndef SQLITE_MAX_COLUMN
+# define SQLITE_MAX_COLUMN 2000
+#endif
+
+/*
+** The maximum length of a single SQL statement in bytes.
+**
+** It used to be the case that setting this value to zero would
+** turn the limit off. That is no longer true. It is not possible
+** to turn this limit off.
+*/
+#ifndef SQLITE_MAX_SQL_LENGTH
+# define SQLITE_MAX_SQL_LENGTH 1000000000
+#endif
+
+/*
+** The maximum depth of an expression tree. This is limited to
+** some extent by SQLITE_MAX_SQL_LENGTH. But sometime you might
+** want to place more severe limits on the complexity of an
+** expression.
+**
+** A value of 0 used to mean that the limit was not enforced.
+** But that is no longer true. The limit is now strictly enforced
+** at all times.
+*/
+#ifndef SQLITE_MAX_EXPR_DEPTH
+# define SQLITE_MAX_EXPR_DEPTH 1000
+#endif
+
+/*
+** The maximum number of terms in a compound SELECT statement.
+** The code generator for compound SELECT statements does one
+** level of recursion for each term. A stack overflow can result
+** if the number of terms is too large. In practice, most SQL
+** never has more than 3 or 4 terms. Use a value of 0 to disable
+** any limit on the number of terms in a compount SELECT.
+*/
+#ifndef SQLITE_MAX_COMPOUND_SELECT
+# define SQLITE_MAX_COMPOUND_SELECT 500
+#endif
+
+/*
+** The maximum number of opcodes in a VDBE program.
+** Not currently enforced.
+*/
+#ifndef SQLITE_MAX_VDBE_OP
+# define SQLITE_MAX_VDBE_OP 25000
+#endif
+
+/*
+** The maximum number of arguments to an SQL function.
+*/
+#ifndef SQLITE_MAX_FUNCTION_ARG
+# define SQLITE_MAX_FUNCTION_ARG 127
+#endif
+
+/*
+** The maximum number of in-memory pages to use for the main database
+** table and for temporary tables. The SQLITE_DEFAULT_CACHE_SIZE
+*/
+#ifndef SQLITE_DEFAULT_CACHE_SIZE
+# define SQLITE_DEFAULT_CACHE_SIZE 2000
+#endif
+#ifndef SQLITE_DEFAULT_TEMP_CACHE_SIZE
+# define SQLITE_DEFAULT_TEMP_CACHE_SIZE 500
+#endif
+
+/*
+** The default number of frames to accumulate in the log file before
+** checkpointing the database in WAL mode.
+*/
+#ifndef SQLITE_DEFAULT_WAL_AUTOCHECKPOINT
+# define SQLITE_DEFAULT_WAL_AUTOCHECKPOINT 1000
+#endif
+
+/*
+** The maximum number of attached databases. This must be between 0
+** and 62. The upper bound on 62 is because a 64-bit integer bitmap
+** is used internally to track attached databases.
+*/
+#ifndef SQLITE_MAX_ATTACHED
+# define SQLITE_MAX_ATTACHED 10
+#endif
+
+
+/*
+** The maximum value of a ?nnn wildcard that the parser will accept.
+*/
+#ifndef SQLITE_MAX_VARIABLE_NUMBER
+# define SQLITE_MAX_VARIABLE_NUMBER 999
+#endif
+
+/* Maximum page size. The upper bound on this value is 65536. This a limit
+** imposed by the use of 16-bit offsets within each page.
+**
+** Earlier versions of SQLite allowed the user to change this value at
+** compile time. This is no longer permitted, on the grounds that it creates
+** a library that is technically incompatible with an SQLite library
+** compiled with a different limit. If a process operating on a database
+** with a page-size of 65536 bytes crashes, then an instance of SQLite
+** compiled with the default page-size limit will not be able to rollback
+** the aborted transaction. This could lead to database corruption.
+*/
+#ifdef SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_MAX_PAGE_SIZE
+#endif
+#define SQLITE_MAX_PAGE_SIZE 65536
+
+
+/*
+** The default size of a database page.
+*/
+#ifndef SQLITE_DEFAULT_PAGE_SIZE
+# define SQLITE_DEFAULT_PAGE_SIZE 1024
+#endif
+#if SQLITE_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_DEFAULT_PAGE_SIZE
+# define SQLITE_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
+#endif
+
+/*
+** Ordinarily, if no value is explicitly provided, SQLite creates databases
+** with page size SQLITE_DEFAULT_PAGE_SIZE. However, based on certain
+** device characteristics (sector-size and atomic write() support),
+** SQLite may choose a larger value. This constant is the maximum value
+** SQLite will choose on its own.
+*/
+#ifndef SQLITE_MAX_DEFAULT_PAGE_SIZE
+# define SQLITE_MAX_DEFAULT_PAGE_SIZE 8192
+#endif
+#if SQLITE_MAX_DEFAULT_PAGE_SIZE>SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_MAX_DEFAULT_PAGE_SIZE
+# define SQLITE_MAX_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
+#endif
+
+
+/*
+** Maximum number of pages in one database file.
+**
+** This is really just the default value for the max_page_count pragma.
+** This value can be lowered (or raised) at run-time using that the
+** max_page_count macro.
+*/
+#ifndef SQLITE_MAX_PAGE_COUNT
+# define SQLITE_MAX_PAGE_COUNT 1073741823
+#endif
+
+/*
+** Maximum length (in bytes) of the pattern in a LIKE or GLOB
+** operator.
+*/
+#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
+# define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
+#endif
+
+/*
+** Maximum depth of recursion for triggers.
+**
+** A value of 1 means that a trigger program will not be able to itself
+** fire any triggers. A value of 0 means that no trigger programs at all
+** may be executed.
+*/
+#ifndef SQLITE_MAX_TRIGGER_DEPTH
+# define SQLITE_MAX_TRIGGER_DEPTH 1000
+#endif
+
+/************** End of sqliteLimit.h *****************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+
+/* Disable nuisance warnings on Borland compilers */
+#if defined(__BORLANDC__)
+#pragma warn -rch /* unreachable code */
+#pragma warn -ccc /* Condition is always true or false */
+#pragma warn -aus /* Assigned value is never used */
+#pragma warn -csu /* Comparing signed and unsigned */
+#pragma warn -spa /* Suspicious pointer arithmetic */
+#endif
+
+/* Needed for various definitions... */
+#ifndef _GNU_SOURCE
+# define _GNU_SOURCE
+#endif
+
+#if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
+# define _BSD_SOURCE
+#endif
+
+/*
+** Include standard header files as necessary
+*/
+#ifdef HAVE_STDINT_H
+#include
+#endif
+#ifdef HAVE_INTTYPES_H
+#include
+#endif
+
+/*
+** The following macros are used to cast pointers to integers and
+** integers to pointers. The way you do this varies from one compiler
+** to the next, so we have developed the following set of #if statements
+** to generate appropriate macros for a wide range of compilers.
+**
+** The correct "ANSI" way to do this is to use the intptr_t type.
+** Unfortunately, that typedef is not available on all compilers, or
+** if it is available, it requires an #include of specific headers
+** that vary from one machine to the next.
+**
+** Ticket #3860: The llvm-gcc-4.2 compiler from Apple chokes on
+** the ((void*)&((char*)0)[X]) construct. But MSVC chokes on ((void*)(X)).
+** So we have to define the macros in different ways depending on the
+** compiler.
+*/
+#if defined(__PTRDIFF_TYPE__) /* This case should work for GCC */
+# define SQLITE_INT_TO_PTR(X) ((void*)(__PTRDIFF_TYPE__)(X))
+# define SQLITE_PTR_TO_INT(X) ((int)(__PTRDIFF_TYPE__)(X))
+#elif !defined(__GNUC__) /* Works for compilers other than LLVM */
+# define SQLITE_INT_TO_PTR(X) ((void*)&((char*)0)[X])
+# define SQLITE_PTR_TO_INT(X) ((int)(((char*)X)-(char*)0))
+#elif defined(HAVE_STDINT_H) /* Use this case if we have ANSI headers */
+# define SQLITE_INT_TO_PTR(X) ((void*)(intptr_t)(X))
+# define SQLITE_PTR_TO_INT(X) ((int)(intptr_t)(X))
+#else /* Generates a warning - but it always works */
+# define SQLITE_INT_TO_PTR(X) ((void*)(X))
+# define SQLITE_PTR_TO_INT(X) ((int)(X))
+#endif
+
+/*
+** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
+** 0 means mutexes are permanently disable and the library is never
+** threadsafe. 1 means the library is serialized which is the highest
+** level of threadsafety. 2 means the library is multithreaded - multiple
+** threads can use SQLite as long as no two threads try to use the same
+** database connection at the same time.
+**
+** Older versions of SQLite used an optional THREADSAFE macro.
+** We support that for legacy.
+*/
+#if !defined(SQLITE_THREADSAFE)
+# if defined(THREADSAFE)
+# define SQLITE_THREADSAFE THREADSAFE
+# else
+# define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
+# endif
+#endif
+
+/*
+** Powersafe overwrite is on by default. But can be turned off using
+** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
+*/
+#ifndef SQLITE_POWERSAFE_OVERWRITE
+# define SQLITE_POWERSAFE_OVERWRITE 1
+#endif
+
+/*
+** The SQLITE_DEFAULT_MEMSTATUS macro must be defined as either 0 or 1.
+** It determines whether or not the features related to
+** SQLITE_CONFIG_MEMSTATUS are available by default or not. This value can
+** be overridden at runtime using the sqlite3_config() API.
+*/
+#if !defined(SQLITE_DEFAULT_MEMSTATUS)
+# define SQLITE_DEFAULT_MEMSTATUS 1
+#endif
+
+/*
+** Exactly one of the following macros must be defined in order to
+** specify which memory allocation subsystem to use.
+**
+** SQLITE_SYSTEM_MALLOC // Use normal system malloc()
+** SQLITE_WIN32_MALLOC // Use Win32 native heap API
+** SQLITE_ZERO_MALLOC // Use a stub allocator that always fails
+** SQLITE_MEMDEBUG // Debugging version of system malloc()
+**
+** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
+** assert() macro is enabled, each call into the Win32 native heap subsystem
+** will cause HeapValidate to be called. If heap validation should fail, an
+** assertion will be triggered.
+**
+** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
+** the default.
+*/
+#if defined(SQLITE_SYSTEM_MALLOC) \
+ + defined(SQLITE_WIN32_MALLOC) \
+ + defined(SQLITE_ZERO_MALLOC) \
+ + defined(SQLITE_MEMDEBUG)>1
+# error "Two or more of the following compile-time configuration options\
+ are defined but at most one is allowed:\
+ SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
+ SQLITE_ZERO_MALLOC"
+#endif
+#if defined(SQLITE_SYSTEM_MALLOC) \
+ + defined(SQLITE_WIN32_MALLOC) \
+ + defined(SQLITE_ZERO_MALLOC) \
+ + defined(SQLITE_MEMDEBUG)==0
+# define SQLITE_SYSTEM_MALLOC 1
+#endif
+
+/*
+** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
+** sizes of memory allocations below this value where possible.
+*/
+#if !defined(SQLITE_MALLOC_SOFT_LIMIT)
+# define SQLITE_MALLOC_SOFT_LIMIT 1024
+#endif
+
+/*
+** We need to define _XOPEN_SOURCE as follows in order to enable
+** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
+** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
+** it.
+*/
+#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
+# define _XOPEN_SOURCE 600
+#endif
+
+/*
+** NDEBUG and SQLITE_DEBUG are opposites. It should always be true that
+** defined(NDEBUG)==!defined(SQLITE_DEBUG). If this is not currently true,
+** make it true by defining or undefining NDEBUG.
+**
+** Setting NDEBUG makes the code smaller and faster by disabling the
+** assert() statements in the code. So we want the default action
+** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
+** is set. Thus NDEBUG becomes an opt-in rather than an opt-out
+** feature.
+*/
+#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
+# define NDEBUG 1
+#endif
+#if defined(NDEBUG) && defined(SQLITE_DEBUG)
+# undef NDEBUG
+#endif
+
+/*
+** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
+*/
+#if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
+# define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
+#endif
+
+/*
+** The testcase() macro is used to aid in coverage testing. When
+** doing coverage testing, the condition inside the argument to
+** testcase() must be evaluated both true and false in order to
+** get full branch coverage. The testcase() macro is inserted
+** to help ensure adequate test coverage in places where simple
+** condition/decision coverage is inadequate. For example, testcase()
+** can be used to make sure boundary values are tested. For
+** bitmask tests, testcase() can be used to make sure each bit
+** is significant and used at least once. On switch statements
+** where multiple cases go to the same block of code, testcase()
+** can insure that all cases are evaluated.
+**
+*/
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE void sqlite3Coverage(int);
+# define testcase(X) if( X ){ sqlite3Coverage(__LINE__); }
+#else
+# define testcase(X)
+#endif
+
+/*
+** The TESTONLY macro is used to enclose variable declarations or
+** other bits of code that are needed to support the arguments
+** within testcase() and assert() macros.
+*/
+#if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
+# define TESTONLY(X) X
+#else
+# define TESTONLY(X)
+#endif
+
+/*
+** Sometimes we need a small amount of code such as a variable initialization
+** to setup for a later assert() statement. We do not want this code to
+** appear when assert() is disabled. The following macro is therefore
+** used to contain that setup code. The "VVA" acronym stands for
+** "Verification, Validation, and Accreditation". In other words, the
+** code within VVA_ONLY() will only run during verification processes.
+*/
+#ifndef NDEBUG
+# define VVA_ONLY(X) X
+#else
+# define VVA_ONLY(X)
+#endif
+
+/*
+** The ALWAYS and NEVER macros surround boolean expressions which
+** are intended to always be true or false, respectively. Such
+** expressions could be omitted from the code completely. But they
+** are included in a few cases in order to enhance the resilience
+** of SQLite to unexpected behavior - to make the code "self-healing"
+** or "ductile" rather than being "brittle" and crashing at the first
+** hint of unplanned behavior.
+**
+** In other words, ALWAYS and NEVER are added for defensive code.
+**
+** When doing coverage testing ALWAYS and NEVER are hard-coded to
+** be true and false so that the unreachable code they specify will
+** not be counted as untested code.
+*/
+#if defined(SQLITE_COVERAGE_TEST)
+# define ALWAYS(X) (1)
+# define NEVER(X) (0)
+#elif !defined(NDEBUG)
+# define ALWAYS(X) ((X)?1:(assert(0),0))
+# define NEVER(X) ((X)?(assert(0),1):0)
+#else
+# define ALWAYS(X) (X)
+# define NEVER(X) (X)
+#endif
+
+/*
+** Return true (non-zero) if the input is a integer that is too large
+** to fit in 32-bits. This macro is used inside of various testcase()
+** macros to verify that we have tested SQLite for large-file support.
+*/
+#define IS_BIG_INT(X) (((X)&~(i64)0xffffffff)!=0)
+
+/*
+** The macro unlikely() is a hint that surrounds a boolean
+** expression that is usually false. Macro likely() surrounds
+** a boolean expression that is usually true. These hints could,
+** in theory, be used by the compiler to generate better code, but
+** currently they are just comments for human readers.
+*/
+#define likely(X) (X)
+#define unlikely(X) (X)
+
+/************** Include hash.h in the middle of sqliteInt.h ******************/
+/************** Begin file hash.h ********************************************/
+/*
+** 2001 September 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the header file for the generic hash-table implementation
+** used in SQLite.
+*/
+#ifndef _SQLITE_HASH_H_
+#define _SQLITE_HASH_H_
+
+/* Forward declarations of structures. */
+typedef struct Hash Hash;
+typedef struct HashElem HashElem;
+
+/* A complete hash table is an instance of the following structure.
+** The internals of this structure are intended to be opaque -- client
+** code should not attempt to access or modify the fields of this structure
+** directly. Change this structure only by using the routines below.
+** However, some of the "procedures" and "functions" for modifying and
+** accessing this structure are really macros, so we can't really make
+** this structure opaque.
+**
+** All elements of the hash table are on a single doubly-linked list.
+** Hash.first points to the head of this list.
+**
+** There are Hash.htsize buckets. Each bucket points to a spot in
+** the global doubly-linked list. The contents of the bucket are the
+** element pointed to plus the next _ht.count-1 elements in the list.
+**
+** Hash.htsize and Hash.ht may be zero. In that case lookup is done
+** by a linear search of the global list. For small tables, the
+** Hash.ht table is never allocated because if there are few elements
+** in the table, it is faster to do a linear search than to manage
+** the hash table.
+*/
+struct Hash {
+ unsigned int htsize; /* Number of buckets in the hash table */
+ unsigned int count; /* Number of entries in this table */
+ HashElem *first; /* The first element of the array */
+ struct _ht { /* the hash table */
+ int count; /* Number of entries with this hash */
+ HashElem *chain; /* Pointer to first entry with this hash */
+ } *ht;
+};
+
+/* Each element in the hash table is an instance of the following
+** structure. All elements are stored on a single doubly-linked list.
+**
+** Again, this structure is intended to be opaque, but it can't really
+** be opaque because it is used by macros.
+*/
+struct HashElem {
+ HashElem *next, *prev; /* Next and previous elements in the table */
+ void *data; /* Data associated with this element */
+ const char *pKey; int nKey; /* Key associated with this element */
+};
+
+/*
+** Access routines. To delete, insert a NULL pointer.
+*/
+SQLITE_PRIVATE void sqlite3HashInit(Hash*);
+SQLITE_PRIVATE void *sqlite3HashInsert(Hash*, const char *pKey, int nKey, void *pData);
+SQLITE_PRIVATE void *sqlite3HashFind(const Hash*, const char *pKey, int nKey);
+SQLITE_PRIVATE void sqlite3HashClear(Hash*);
+
+/*
+** Macros for looping over all elements of a hash table. The idiom is
+** like this:
+**
+** Hash h;
+** HashElem *p;
+** ...
+** for(p=sqliteHashFirst(&h); p; p=sqliteHashNext(p)){
+** SomeStructure *pData = sqliteHashData(p);
+** // do something with pData
+** }
+*/
+#define sqliteHashFirst(H) ((H)->first)
+#define sqliteHashNext(E) ((E)->next)
+#define sqliteHashData(E) ((E)->data)
+/* #define sqliteHashKey(E) ((E)->pKey) // NOT USED */
+/* #define sqliteHashKeysize(E) ((E)->nKey) // NOT USED */
+
+/*
+** Number of entries in a hash table
+*/
+/* #define sqliteHashCount(H) ((H)->count) // NOT USED */
+
+#endif /* _SQLITE_HASH_H_ */
+
+/************** End of hash.h ************************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include parse.h in the middle of sqliteInt.h *****************/
+/************** Begin file parse.h *******************************************/
+#define TK_SEMI 1
+#define TK_EXPLAIN 2
+#define TK_QUERY 3
+#define TK_PLAN 4
+#define TK_BEGIN 5
+#define TK_TRANSACTION 6
+#define TK_DEFERRED 7
+#define TK_IMMEDIATE 8
+#define TK_EXCLUSIVE 9
+#define TK_COMMIT 10
+#define TK_END 11
+#define TK_ROLLBACK 12
+#define TK_SAVEPOINT 13
+#define TK_RELEASE 14
+#define TK_TO 15
+#define TK_TABLE 16
+#define TK_CREATE 17
+#define TK_IF 18
+#define TK_NOT 19
+#define TK_EXISTS 20
+#define TK_TEMP 21
+#define TK_LP 22
+#define TK_RP 23
+#define TK_AS 24
+#define TK_WITHOUT 25
+#define TK_COMMA 26
+#define TK_ID 27
+#define TK_INDEXED 28
+#define TK_ABORT 29
+#define TK_ACTION 30
+#define TK_AFTER 31
+#define TK_ANALYZE 32
+#define TK_ASC 33
+#define TK_ATTACH 34
+#define TK_BEFORE 35
+#define TK_BY 36
+#define TK_CASCADE 37
+#define TK_CAST 38
+#define TK_COLUMNKW 39
+#define TK_CONFLICT 40
+#define TK_DATABASE 41
+#define TK_DESC 42
+#define TK_DETACH 43
+#define TK_EACH 44
+#define TK_FAIL 45
+#define TK_FOR 46
+#define TK_IGNORE 47
+#define TK_INITIALLY 48
+#define TK_INSTEAD 49
+#define TK_LIKE_KW 50
+#define TK_MATCH 51
+#define TK_NO 52
+#define TK_KEY 53
+#define TK_OF 54
+#define TK_OFFSET 55
+#define TK_PRAGMA 56
+#define TK_RAISE 57
+#define TK_RECURSIVE 58
+#define TK_REPLACE 59
+#define TK_RESTRICT 60
+#define TK_ROW 61
+#define TK_TRIGGER 62
+#define TK_VACUUM 63
+#define TK_VIEW 64
+#define TK_VIRTUAL 65
+#define TK_WITH 66
+#define TK_REINDEX 67
+#define TK_RENAME 68
+#define TK_CTIME_KW 69
+#define TK_ANY 70
+#define TK_OR 71
+#define TK_AND 72
+#define TK_IS 73
+#define TK_BETWEEN 74
+#define TK_IN 75
+#define TK_ISNULL 76
+#define TK_NOTNULL 77
+#define TK_NE 78
+#define TK_EQ 79
+#define TK_GT 80
+#define TK_LE 81
+#define TK_LT 82
+#define TK_GE 83
+#define TK_ESCAPE 84
+#define TK_BITAND 85
+#define TK_BITOR 86
+#define TK_LSHIFT 87
+#define TK_RSHIFT 88
+#define TK_PLUS 89
+#define TK_MINUS 90
+#define TK_STAR 91
+#define TK_SLASH 92
+#define TK_REM 93
+#define TK_CONCAT 94
+#define TK_COLLATE 95
+#define TK_BITNOT 96
+#define TK_STRING 97
+#define TK_JOIN_KW 98
+#define TK_CONSTRAINT 99
+#define TK_DEFAULT 100
+#define TK_NULL 101
+#define TK_PRIMARY 102
+#define TK_UNIQUE 103
+#define TK_CHECK 104
+#define TK_REFERENCES 105
+#define TK_AUTOINCR 106
+#define TK_ON 107
+#define TK_INSERT 108
+#define TK_DELETE 109
+#define TK_UPDATE 110
+#define TK_SET 111
+#define TK_DEFERRABLE 112
+#define TK_FOREIGN 113
+#define TK_DROP 114
+#define TK_UNION 115
+#define TK_ALL 116
+#define TK_EXCEPT 117
+#define TK_INTERSECT 118
+#define TK_SELECT 119
+#define TK_VALUES 120
+#define TK_DISTINCT 121
+#define TK_DOT 122
+#define TK_FROM 123
+#define TK_JOIN 124
+#define TK_USING 125
+#define TK_ORDER 126
+#define TK_GROUP 127
+#define TK_HAVING 128
+#define TK_LIMIT 129
+#define TK_WHERE 130
+#define TK_INTO 131
+#define TK_INTEGER 132
+#define TK_FLOAT 133
+#define TK_BLOB 134
+#define TK_VARIABLE 135
+#define TK_CASE 136
+#define TK_WHEN 137
+#define TK_THEN 138
+#define TK_ELSE 139
+#define TK_INDEX 140
+#define TK_ALTER 141
+#define TK_ADD 142
+#define TK_TO_TEXT 143
+#define TK_TO_BLOB 144
+#define TK_TO_NUMERIC 145
+#define TK_TO_INT 146
+#define TK_TO_REAL 147
+#define TK_ISNOT 148
+#define TK_END_OF_FILE 149
+#define TK_ILLEGAL 150
+#define TK_SPACE 151
+#define TK_UNCLOSED_STRING 152
+#define TK_FUNCTION 153
+#define TK_COLUMN 154
+#define TK_AGG_FUNCTION 155
+#define TK_AGG_COLUMN 156
+#define TK_UMINUS 157
+#define TK_UPLUS 158
+#define TK_REGISTER 159
+
+/************** End of parse.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+#include
+#include
+#include
+#include
+#include
+
+/*
+** If compiling for a processor that lacks floating point support,
+** substitute integer for floating-point
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define double sqlite_int64
+# define float sqlite_int64
+# define LONGDOUBLE_TYPE sqlite_int64
+# ifndef SQLITE_BIG_DBL
+# define SQLITE_BIG_DBL (((sqlite3_int64)1)<<50)
+# endif
+# define SQLITE_OMIT_DATETIME_FUNCS 1
+# define SQLITE_OMIT_TRACE 1
+# undef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
+# undef SQLITE_HAVE_ISNAN
+#endif
+#ifndef SQLITE_BIG_DBL
+# define SQLITE_BIG_DBL (1e99)
+#endif
+
+/*
+** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
+** afterward. Having this macro allows us to cause the C compiler
+** to omit code used by TEMP tables without messy #ifndef statements.
+*/
+#ifdef SQLITE_OMIT_TEMPDB
+#define OMIT_TEMPDB 1
+#else
+#define OMIT_TEMPDB 0
+#endif
+
+/*
+** The "file format" number is an integer that is incremented whenever
+** the VDBE-level file format changes. The following macros define the
+** the default file format for new databases and the maximum file format
+** that the library can read.
+*/
+#define SQLITE_MAX_FILE_FORMAT 4
+#ifndef SQLITE_DEFAULT_FILE_FORMAT
+# define SQLITE_DEFAULT_FILE_FORMAT 4
+#endif
+
+/*
+** Determine whether triggers are recursive by default. This can be
+** changed at run-time using a pragma.
+*/
+#ifndef SQLITE_DEFAULT_RECURSIVE_TRIGGERS
+# define SQLITE_DEFAULT_RECURSIVE_TRIGGERS 0
+#endif
+
+/*
+** Provide a default value for SQLITE_TEMP_STORE in case it is not specified
+** on the command-line
+*/
+#ifndef SQLITE_TEMP_STORE
+# define SQLITE_TEMP_STORE 1
+# define SQLITE_TEMP_STORE_xc 1 /* Exclude from ctime.c */
+#endif
+
+/*
+** GCC does not define the offsetof() macro so we'll have to do it
+** ourselves.
+*/
+#ifndef offsetof
+#define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
+#endif
+
+/*
+** Macros to compute minimum and maximum of two numbers.
+*/
+#define MIN(A,B) ((A)<(B)?(A):(B))
+#define MAX(A,B) ((A)>(B)?(A):(B))
+
+/*
+** Check to see if this machine uses EBCDIC. (Yes, believe it or
+** not, there are still machines out there that use EBCDIC.)
+*/
+#if 'A' == '\301'
+# define SQLITE_EBCDIC 1
+#else
+# define SQLITE_ASCII 1
+#endif
+
+/*
+** Integers of known sizes. These typedefs might change for architectures
+** where the sizes very. Preprocessor macros are available so that the
+** types can be conveniently redefined at compile-type. Like this:
+**
+** cc '-DUINTPTR_TYPE=long long int' ...
+*/
+#ifndef UINT32_TYPE
+# ifdef HAVE_UINT32_T
+# define UINT32_TYPE uint32_t
+# else
+# define UINT32_TYPE unsigned int
+# endif
+#endif
+#ifndef UINT16_TYPE
+# ifdef HAVE_UINT16_T
+# define UINT16_TYPE uint16_t
+# else
+# define UINT16_TYPE unsigned short int
+# endif
+#endif
+#ifndef INT16_TYPE
+# ifdef HAVE_INT16_T
+# define INT16_TYPE int16_t
+# else
+# define INT16_TYPE short int
+# endif
+#endif
+#ifndef UINT8_TYPE
+# ifdef HAVE_UINT8_T
+# define UINT8_TYPE uint8_t
+# else
+# define UINT8_TYPE unsigned char
+# endif
+#endif
+#ifndef INT8_TYPE
+# ifdef HAVE_INT8_T
+# define INT8_TYPE int8_t
+# else
+# define INT8_TYPE signed char
+# endif
+#endif
+#ifndef LONGDOUBLE_TYPE
+# define LONGDOUBLE_TYPE long double
+#endif
+typedef sqlite_int64 i64; /* 8-byte signed integer */
+typedef sqlite_uint64 u64; /* 8-byte unsigned integer */
+typedef UINT32_TYPE u32; /* 4-byte unsigned integer */
+typedef UINT16_TYPE u16; /* 2-byte unsigned integer */
+typedef INT16_TYPE i16; /* 2-byte signed integer */
+typedef UINT8_TYPE u8; /* 1-byte unsigned integer */
+typedef INT8_TYPE i8; /* 1-byte signed integer */
+
+/*
+** SQLITE_MAX_U32 is a u64 constant that is the maximum u64 value
+** that can be stored in a u32 without loss of data. The value
+** is 0x00000000ffffffff. But because of quirks of some compilers, we
+** have to specify the value in the less intuitive manner shown:
+*/
+#define SQLITE_MAX_U32 ((((u64)1)<<32)-1)
+
+/*
+** The datatype used to store estimates of the number of rows in a
+** table or index. This is an unsigned integer type. For 99.9% of
+** the world, a 32-bit integer is sufficient. But a 64-bit integer
+** can be used at compile-time if desired.
+*/
+#ifdef SQLITE_64BIT_STATS
+ typedef u64 tRowcnt; /* 64-bit only if requested at compile-time */
+#else
+ typedef u32 tRowcnt; /* 32-bit is the default */
+#endif
+
+/*
+** Estimated quantities used for query planning are stored as 16-bit
+** logarithms. For quantity X, the value stored is 10*log2(X). This
+** gives a possible range of values of approximately 1.0e986 to 1e-986.
+** But the allowed values are "grainy". Not every value is representable.
+** For example, quantities 16 and 17 are both represented by a LogEst
+** of 40. However, since LogEst quantaties are suppose to be estimates,
+** not exact values, this imprecision is not a problem.
+**
+** "LogEst" is short for "Logarithmic Estimate".
+**
+** Examples:
+** 1 -> 0 20 -> 43 10000 -> 132
+** 2 -> 10 25 -> 46 25000 -> 146
+** 3 -> 16 100 -> 66 1000000 -> 199
+** 4 -> 20 1000 -> 99 1048576 -> 200
+** 10 -> 33 1024 -> 100 4294967296 -> 320
+**
+** The LogEst can be negative to indicate fractional values.
+** Examples:
+**
+** 0.5 -> -10 0.1 -> -33 0.0625 -> -40
+*/
+typedef INT16_TYPE LogEst;
+
+/*
+** Macros to determine whether the machine is big or little endian,
+** and whether or not that determination is run-time or compile-time.
+**
+** For best performance, an attempt is made to guess at the byte-order
+** using C-preprocessor macros. If that is unsuccessful, or if
+** -DSQLITE_RUNTIME_BYTEORDER=1 is set, then byte-order is determined
+** at run-time.
+*/
+#ifdef SQLITE_AMALGAMATION
+SQLITE_PRIVATE const int sqlite3one = 1;
+#else
+SQLITE_PRIVATE const int sqlite3one;
+#endif
+#if (defined(i386) || defined(__i386__) || defined(_M_IX86) || \
+ defined(__x86_64) || defined(__x86_64__) || defined(_M_X64) || \
+ defined(_M_AMD64) || defined(_M_ARM) || defined(__x86) || \
+ defined(__arm__)) && !defined(SQLITE_RUNTIME_BYTEORDER)
+# define SQLITE_BYTEORDER 1234
+# define SQLITE_BIGENDIAN 0
+# define SQLITE_LITTLEENDIAN 1
+# define SQLITE_UTF16NATIVE SQLITE_UTF16LE
+#endif
+#if (defined(sparc) || defined(__ppc__)) \
+ && !defined(SQLITE_RUNTIME_BYTEORDER)
+# define SQLITE_BYTEORDER 4321
+# define SQLITE_BIGENDIAN 1
+# define SQLITE_LITTLEENDIAN 0
+# define SQLITE_UTF16NATIVE SQLITE_UTF16BE
+#endif
+#if !defined(SQLITE_BYTEORDER)
+# define SQLITE_BYTEORDER 0 /* 0 means "unknown at compile-time" */
+# define SQLITE_BIGENDIAN (*(char *)(&sqlite3one)==0)
+# define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
+# define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
+#endif
+
+/*
+** Constants for the largest and smallest possible 64-bit signed integers.
+** These macros are designed to work correctly on both 32-bit and 64-bit
+** compilers.
+*/
+#define LARGEST_INT64 (0xffffffff|(((i64)0x7fffffff)<<32))
+#define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
+
+/*
+** Round up a number to the next larger multiple of 8. This is used
+** to force 8-byte alignment on 64-bit architectures.
+*/
+#define ROUND8(x) (((x)+7)&~7)
+
+/*
+** Round down to the nearest multiple of 8
+*/
+#define ROUNDDOWN8(x) ((x)&~7)
+
+/*
+** Assert that the pointer X is aligned to an 8-byte boundary. This
+** macro is used only within assert() to verify that the code gets
+** all alignment restrictions correct.
+**
+** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
+** underlying malloc() implemention might return us 4-byte aligned
+** pointers. In that case, only verify 4-byte alignment.
+*/
+#ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
+# define EIGHT_BYTE_ALIGNMENT(X) ((((char*)(X) - (char*)0)&3)==0)
+#else
+# define EIGHT_BYTE_ALIGNMENT(X) ((((char*)(X) - (char*)0)&7)==0)
+#endif
+
+/*
+** Disable MMAP on platforms where it is known to not work
+*/
+#if defined(__OpenBSD__) || defined(__QNXNTO__)
+# undef SQLITE_MAX_MMAP_SIZE
+# define SQLITE_MAX_MMAP_SIZE 0
+#endif
+
+/*
+** Default maximum size of memory used by memory-mapped I/O in the VFS
+*/
+#ifdef __APPLE__
+# include
+# if TARGET_OS_IPHONE
+# undef SQLITE_MAX_MMAP_SIZE
+# define SQLITE_MAX_MMAP_SIZE 0
+# endif
+#endif
+#ifndef SQLITE_MAX_MMAP_SIZE
+# if defined(__linux__) \
+ || defined(_WIN32) \
+ || (defined(__APPLE__) && defined(__MACH__)) \
+ || defined(__sun)
+# define SQLITE_MAX_MMAP_SIZE 0x7fff0000 /* 2147418112 */
+# else
+# define SQLITE_MAX_MMAP_SIZE 0
+# endif
+# define SQLITE_MAX_MMAP_SIZE_xc 1 /* exclude from ctime.c */
+#endif
+
+/*
+** The default MMAP_SIZE is zero on all platforms. Or, even if a larger
+** default MMAP_SIZE is specified at compile-time, make sure that it does
+** not exceed the maximum mmap size.
+*/
+#ifndef SQLITE_DEFAULT_MMAP_SIZE
+# define SQLITE_DEFAULT_MMAP_SIZE 0
+# define SQLITE_DEFAULT_MMAP_SIZE_xc 1 /* Exclude from ctime.c */
+#endif
+#if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
+# undef SQLITE_DEFAULT_MMAP_SIZE
+# define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
+#endif
+
+/*
+** Only one of SQLITE_ENABLE_STAT3 or SQLITE_ENABLE_STAT4 can be defined.
+** Priority is given to SQLITE_ENABLE_STAT4. If either are defined, also
+** define SQLITE_ENABLE_STAT3_OR_STAT4
+*/
+#ifdef SQLITE_ENABLE_STAT4
+# undef SQLITE_ENABLE_STAT3
+# define SQLITE_ENABLE_STAT3_OR_STAT4 1
+#elif SQLITE_ENABLE_STAT3
+# define SQLITE_ENABLE_STAT3_OR_STAT4 1
+#elif SQLITE_ENABLE_STAT3_OR_STAT4
+# undef SQLITE_ENABLE_STAT3_OR_STAT4
+#endif
+
+/*
+** An instance of the following structure is used to store the busy-handler
+** callback for a given sqlite handle.
+**
+** The sqlite.busyHandler member of the sqlite struct contains the busy
+** callback for the database handle. Each pager opened via the sqlite
+** handle is passed a pointer to sqlite.busyHandler. The busy-handler
+** callback is currently invoked only from within pager.c.
+*/
+typedef struct BusyHandler BusyHandler;
+struct BusyHandler {
+ int (*xFunc)(void *,int); /* The busy callback */
+ void *pArg; /* First arg to busy callback */
+ int nBusy; /* Incremented with each busy call */
+};
+
+/*
+** Name of the master database table. The master database table
+** is a special table that holds the names and attributes of all
+** user tables and indices.
+*/
+#define MASTER_NAME "sqlite_master"
+#define TEMP_MASTER_NAME "sqlite_temp_master"
+
+/*
+** The root-page of the master database table.
+*/
+#define MASTER_ROOT 1
+
+/*
+** The name of the schema table.
+*/
+#define SCHEMA_TABLE(x) ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
+
+/*
+** A convenience macro that returns the number of elements in
+** an array.
+*/
+#define ArraySize(X) ((int)(sizeof(X)/sizeof(X[0])))
+
+/*
+** Determine if the argument is a power of two
+*/
+#define IsPowerOfTwo(X) (((X)&((X)-1))==0)
+
+/*
+** The following value as a destructor means to use sqlite3DbFree().
+** The sqlite3DbFree() routine requires two parameters instead of the
+** one parameter that destructors normally want. So we have to introduce
+** this magic value that the code knows to handle differently. Any
+** pointer will work here as long as it is distinct from SQLITE_STATIC
+** and SQLITE_TRANSIENT.
+*/
+#define SQLITE_DYNAMIC ((sqlite3_destructor_type)sqlite3MallocSize)
+
+/*
+** When SQLITE_OMIT_WSD is defined, it means that the target platform does
+** not support Writable Static Data (WSD) such as global and static variables.
+** All variables must either be on the stack or dynamically allocated from
+** the heap. When WSD is unsupported, the variable declarations scattered
+** throughout the SQLite code must become constants instead. The SQLITE_WSD
+** macro is used for this purpose. And instead of referencing the variable
+** directly, we use its constant as a key to lookup the run-time allocated
+** buffer that holds real variable. The constant is also the initializer
+** for the run-time allocated buffer.
+**
+** In the usual case where WSD is supported, the SQLITE_WSD and GLOBAL
+** macros become no-ops and have zero performance impact.
+*/
+#ifdef SQLITE_OMIT_WSD
+ #define SQLITE_WSD const
+ #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
+ #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
+SQLITE_API int sqlite3_wsd_init(int N, int J);
+SQLITE_API void *sqlite3_wsd_find(void *K, int L);
+#else
+ #define SQLITE_WSD
+ #define GLOBAL(t,v) v
+ #define sqlite3GlobalConfig sqlite3Config
+#endif
+
+/*
+** The following macros are used to suppress compiler warnings and to
+** make it clear to human readers when a function parameter is deliberately
+** left unused within the body of a function. This usually happens when
+** a function is called via a function pointer. For example the
+** implementation of an SQL aggregate step callback may not use the
+** parameter indicating the number of arguments passed to the aggregate,
+** if it knows that this is enforced elsewhere.
+**
+** When a function parameter is not used at all within the body of a function,
+** it is generally named "NotUsed" or "NotUsed2" to make things even clearer.
+** However, these macros may also be used to suppress warnings related to
+** parameters that may or may not be used depending on compilation options.
+** For example those parameters only used in assert() statements. In these
+** cases the parameters are named as per the usual conventions.
+*/
+#define UNUSED_PARAMETER(x) (void)(x)
+#define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)
+
+/*
+** Forward references to structures
+*/
+typedef struct AggInfo AggInfo;
+typedef struct AuthContext AuthContext;
+typedef struct AutoincInfo AutoincInfo;
+typedef struct Bitvec Bitvec;
+typedef struct CollSeq CollSeq;
+typedef struct Column Column;
+typedef struct Db Db;
+typedef struct Schema Schema;
+typedef struct Expr Expr;
+typedef struct ExprList ExprList;
+typedef struct ExprSpan ExprSpan;
+typedef struct FKey FKey;
+typedef struct FuncDestructor FuncDestructor;
+typedef struct FuncDef FuncDef;
+typedef struct FuncDefHash FuncDefHash;
+typedef struct IdList IdList;
+typedef struct Index Index;
+typedef struct IndexSample IndexSample;
+typedef struct KeyClass KeyClass;
+typedef struct KeyInfo KeyInfo;
+typedef struct Lookaside Lookaside;
+typedef struct LookasideSlot LookasideSlot;
+typedef struct Module Module;
+typedef struct NameContext NameContext;
+typedef struct Parse Parse;
+typedef struct PrintfArguments PrintfArguments;
+typedef struct RowSet RowSet;
+typedef struct Savepoint Savepoint;
+typedef struct Select Select;
+typedef struct SelectDest SelectDest;
+typedef struct SrcList SrcList;
+typedef struct StrAccum StrAccum;
+typedef struct Table Table;
+typedef struct TableLock TableLock;
+typedef struct Token Token;
+typedef struct Trigger Trigger;
+typedef struct TriggerPrg TriggerPrg;
+typedef struct TriggerStep TriggerStep;
+typedef struct UnpackedRecord UnpackedRecord;
+typedef struct VTable VTable;
+typedef struct VtabCtx VtabCtx;
+typedef struct Walker Walker;
+typedef struct WhereInfo WhereInfo;
+typedef struct With With;
+
+/*
+** Defer sourcing vdbe.h and btree.h until after the "u8" and
+** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
+** pointer types (i.e. FuncDef) defined above.
+*/
+/************** Include btree.h in the middle of sqliteInt.h *****************/
+/************** Begin file btree.h *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite B-Tree file
+** subsystem. See comments in the source code for a detailed description
+** of what each interface routine does.
+*/
+#ifndef _BTREE_H_
+#define _BTREE_H_
+
+/* TODO: This definition is just included so other modules compile. It
+** needs to be revisited.
+*/
+#define SQLITE_N_BTREE_META 10
+
+/*
+** If defined as non-zero, auto-vacuum is enabled by default. Otherwise
+** it must be turned on for each database using "PRAGMA auto_vacuum = 1".
+*/
+#ifndef SQLITE_DEFAULT_AUTOVACUUM
+ #define SQLITE_DEFAULT_AUTOVACUUM 0
+#endif
+
+#define BTREE_AUTOVACUUM_NONE 0 /* Do not do auto-vacuum */
+#define BTREE_AUTOVACUUM_FULL 1 /* Do full auto-vacuum */
+#define BTREE_AUTOVACUUM_INCR 2 /* Incremental vacuum */
+
+/*
+** Forward declarations of structure
+*/
+typedef struct Btree Btree;
+typedef struct BtCursor BtCursor;
+typedef struct BtShared BtShared;
+
+
+SQLITE_PRIVATE int sqlite3BtreeOpen(
+ sqlite3_vfs *pVfs, /* VFS to use with this b-tree */
+ const char *zFilename, /* Name of database file to open */
+ sqlite3 *db, /* Associated database connection */
+ Btree **ppBtree, /* Return open Btree* here */
+ int flags, /* Flags */
+ int vfsFlags /* Flags passed through to VFS open */
+);
+
+/* The flags parameter to sqlite3BtreeOpen can be the bitwise or of the
+** following values.
+**
+** NOTE: These values must match the corresponding PAGER_ values in
+** pager.h.
+*/
+#define BTREE_OMIT_JOURNAL 1 /* Do not create or use a rollback journal */
+#define BTREE_MEMORY 2 /* This is an in-memory DB */
+#define BTREE_SINGLE 4 /* The file contains at most 1 b-tree */
+#define BTREE_UNORDERED 8 /* Use of a hash implementation is OK */
+
+SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
+#if SQLITE_MAX_MMAP_SIZE>0
+SQLITE_PRIVATE int sqlite3BtreeSetMmapLimit(Btree*,sqlite3_int64);
+#endif
+SQLITE_PRIVATE int sqlite3BtreeSetPagerFlags(Btree*,unsigned);
+SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
+SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree*,int);
+SQLITE_PRIVATE u32 sqlite3BtreeLastPage(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeSecureDelete(Btree*,int);
+SQLITE_PRIVATE int sqlite3BtreeGetReserve(Btree*);
+#if defined(SQLITE_HAS_CODEC) || defined(SQLITE_DEBUG)
+SQLITE_PRIVATE int sqlite3BtreeGetReserveNoMutex(Btree *p);
+#endif
+SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *, int);
+SQLITE_PRIVATE int sqlite3BtreeGetAutoVacuum(Btree *);
+SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree*,int);
+SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree*, const char *zMaster);
+SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree*, int);
+SQLITE_PRIVATE int sqlite3BtreeCommit(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeRollback(Btree*,int);
+SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree*,int);
+SQLITE_PRIVATE int sqlite3BtreeCreateTable(Btree*, int*, int flags);
+SQLITE_PRIVATE int sqlite3BtreeIsInTrans(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeIsInReadTrans(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeIsInBackup(Btree*);
+SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
+SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *pBtree);
+SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *pBtree, int iTab, u8 isWriteLock);
+SQLITE_PRIVATE int sqlite3BtreeSavepoint(Btree *, int, int);
+
+SQLITE_PRIVATE const char *sqlite3BtreeGetFilename(Btree *);
+SQLITE_PRIVATE const char *sqlite3BtreeGetJournalname(Btree *);
+SQLITE_PRIVATE int sqlite3BtreeCopyFile(Btree *, Btree *);
+
+SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *);
+
+/* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
+** of the flags shown below.
+**
+** Every SQLite table must have either BTREE_INTKEY or BTREE_BLOBKEY set.
+** With BTREE_INTKEY, the table key is a 64-bit integer and arbitrary data
+** is stored in the leaves. (BTREE_INTKEY is used for SQL tables.) With
+** BTREE_BLOBKEY, the key is an arbitrary BLOB and no content is stored
+** anywhere - the key is the content. (BTREE_BLOBKEY is used for SQL
+** indices.)
+*/
+#define BTREE_INTKEY 1 /* Table has only 64-bit signed integer keys */
+#define BTREE_BLOBKEY 2 /* Table has keys only - no data */
+
+SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree*, int, int*);
+SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int, int*);
+SQLITE_PRIVATE int sqlite3BtreeClearTableOfCursor(BtCursor*);
+SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree*, int);
+
+SQLITE_PRIVATE void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
+SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
+
+SQLITE_PRIVATE int sqlite3BtreeNewDb(Btree *p);
+
+/*
+** The second parameter to sqlite3BtreeGetMeta or sqlite3BtreeUpdateMeta
+** should be one of the following values. The integer values are assigned
+** to constants so that the offset of the corresponding field in an
+** SQLite database header may be found using the following formula:
+**
+** offset = 36 + (idx * 4)
+**
+** For example, the free-page-count field is located at byte offset 36 of
+** the database file header. The incr-vacuum-flag field is located at
+** byte offset 64 (== 36+4*7).
+*/
+#define BTREE_FREE_PAGE_COUNT 0
+#define BTREE_SCHEMA_VERSION 1
+#define BTREE_FILE_FORMAT 2
+#define BTREE_DEFAULT_CACHE_SIZE 3
+#define BTREE_LARGEST_ROOT_PAGE 4
+#define BTREE_TEXT_ENCODING 5
+#define BTREE_USER_VERSION 6
+#define BTREE_INCR_VACUUM 7
+#define BTREE_APPLICATION_ID 8
+
+/*
+** Values that may be OR'd together to form the second argument of an
+** sqlite3BtreeCursorHints() call.
+*/
+#define BTREE_BULKLOAD 0x00000001
+
+SQLITE_PRIVATE int sqlite3BtreeCursor(
+ Btree*, /* BTree containing table to open */
+ int iTable, /* Index of root page */
+ int wrFlag, /* 1 for writing. 0 for read-only */
+ struct KeyInfo*, /* First argument to compare function */
+ BtCursor *pCursor /* Space to write cursor structure */
+);
+SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
+SQLITE_PRIVATE void sqlite3BtreeCursorZero(BtCursor*);
+
+SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
+ BtCursor*,
+ UnpackedRecord *pUnKey,
+ i64 intKey,
+ int bias,
+ int *pRes
+);
+SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor*, int*);
+SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
+ const void *pData, int nData,
+ int nZero, int bias, int seekResult);
+SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor*, int *pRes);
+SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor*, int *pRes);
+SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor*, int *pRes);
+SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor*);
+SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int *pRes);
+SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor*, i64 *pSize);
+SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
+SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor*, u32 *pAmt);
+SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor*, u32 *pAmt);
+SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
+SQLITE_PRIVATE int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);
+
+SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
+SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
+
+SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
+SQLITE_PRIVATE void sqlite3BtreeIncrblobCursor(BtCursor *);
+SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);
+SQLITE_PRIVATE int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
+SQLITE_PRIVATE void sqlite3BtreeCursorHints(BtCursor *, unsigned int mask);
+SQLITE_PRIVATE int sqlite3BtreeIsReadonly(Btree *pBt);
+
+#ifndef NDEBUG
+SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor*);
+#endif
+
+#ifndef SQLITE_OMIT_BTREECOUNT
+SQLITE_PRIVATE int sqlite3BtreeCount(BtCursor *, i64 *);
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
+SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
+#endif
+
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3BtreeCheckpoint(Btree*, int, int *, int *);
+#endif
+
+/*
+** If we are not using shared cache, then there is no need to
+** use mutexes to access the BtShared structures. So make the
+** Enter and Leave procedures no-ops.
+*/
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3BtreeEnter(Btree*);
+SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3*);
+#else
+# define sqlite3BtreeEnter(X)
+# define sqlite3BtreeEnterAll(X)
+#endif
+
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
+SQLITE_PRIVATE int sqlite3BtreeSharable(Btree*);
+SQLITE_PRIVATE void sqlite3BtreeLeave(Btree*);
+SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor*);
+SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor*);
+SQLITE_PRIVATE void sqlite3BtreeLeaveAll(sqlite3*);
+#ifndef NDEBUG
+ /* These routines are used inside assert() statements only. */
+SQLITE_PRIVATE int sqlite3BtreeHoldsMutex(Btree*);
+SQLITE_PRIVATE int sqlite3BtreeHoldsAllMutexes(sqlite3*);
+SQLITE_PRIVATE int sqlite3SchemaMutexHeld(sqlite3*,int,Schema*);
+#endif
+#else
+
+# define sqlite3BtreeSharable(X) 0
+# define sqlite3BtreeLeave(X)
+# define sqlite3BtreeEnterCursor(X)
+# define sqlite3BtreeLeaveCursor(X)
+# define sqlite3BtreeLeaveAll(X)
+
+# define sqlite3BtreeHoldsMutex(X) 1
+# define sqlite3BtreeHoldsAllMutexes(X) 1
+# define sqlite3SchemaMutexHeld(X,Y,Z) 1
+#endif
+
+
+#endif /* _BTREE_H_ */
+
+/************** End of btree.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include vdbe.h in the middle of sqliteInt.h ******************/
+/************** Begin file vdbe.h ********************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Header file for the Virtual DataBase Engine (VDBE)
+**
+** This header defines the interface to the virtual database engine
+** or VDBE. The VDBE implements an abstract machine that runs a
+** simple program to access and modify the underlying database.
+*/
+#ifndef _SQLITE_VDBE_H_
+#define _SQLITE_VDBE_H_
+/* #include */
+
+/*
+** A single VDBE is an opaque structure named "Vdbe". Only routines
+** in the source file sqliteVdbe.c are allowed to see the insides
+** of this structure.
+*/
+typedef struct Vdbe Vdbe;
+
+/*
+** The names of the following types declared in vdbeInt.h are required
+** for the VdbeOp definition.
+*/
+typedef struct Mem Mem;
+typedef struct SubProgram SubProgram;
+
+/*
+** A single instruction of the virtual machine has an opcode
+** and as many as three operands. The instruction is recorded
+** as an instance of the following structure:
+*/
+struct VdbeOp {
+ u8 opcode; /* What operation to perform */
+ signed char p4type; /* One of the P4_xxx constants for p4 */
+ u8 opflags; /* Mask of the OPFLG_* flags in opcodes.h */
+ u8 p5; /* Fifth parameter is an unsigned character */
+ int p1; /* First operand */
+ int p2; /* Second parameter (often the jump destination) */
+ int p3; /* The third parameter */
+ union { /* fourth parameter */
+ int i; /* Integer value if p4type==P4_INT32 */
+ void *p; /* Generic pointer */
+ char *z; /* Pointer to data for string (char array) types */
+ i64 *pI64; /* Used when p4type is P4_INT64 */
+ double *pReal; /* Used when p4type is P4_REAL */
+ FuncDef *pFunc; /* Used when p4type is P4_FUNCDEF */
+ CollSeq *pColl; /* Used when p4type is P4_COLLSEQ */
+ Mem *pMem; /* Used when p4type is P4_MEM */
+ VTable *pVtab; /* Used when p4type is P4_VTAB */
+ KeyInfo *pKeyInfo; /* Used when p4type is P4_KEYINFO */
+ int *ai; /* Used when p4type is P4_INTARRAY */
+ SubProgram *pProgram; /* Used when p4type is P4_SUBPROGRAM */
+ int (*xAdvance)(BtCursor *, int *);
+ } p4;
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
+ char *zComment; /* Comment to improve readability */
+#endif
+#ifdef VDBE_PROFILE
+ u32 cnt; /* Number of times this instruction was executed */
+ u64 cycles; /* Total time spent executing this instruction */
+#endif
+#ifdef SQLITE_VDBE_COVERAGE
+ int iSrcLine; /* Source-code line that generated this opcode */
+#endif
+};
+typedef struct VdbeOp VdbeOp;
+
+
+/*
+** A sub-routine used to implement a trigger program.
+*/
+struct SubProgram {
+ VdbeOp *aOp; /* Array of opcodes for sub-program */
+ int nOp; /* Elements in aOp[] */
+ int nMem; /* Number of memory cells required */
+ int nCsr; /* Number of cursors required */
+ int nOnce; /* Number of OP_Once instructions */
+ void *token; /* id that may be used to recursive triggers */
+ SubProgram *pNext; /* Next sub-program already visited */
+};
+
+/*
+** A smaller version of VdbeOp used for the VdbeAddOpList() function because
+** it takes up less space.
+*/
+struct VdbeOpList {
+ u8 opcode; /* What operation to perform */
+ signed char p1; /* First operand */
+ signed char p2; /* Second parameter (often the jump destination) */
+ signed char p3; /* Third parameter */
+};
+typedef struct VdbeOpList VdbeOpList;
+
+/*
+** Allowed values of VdbeOp.p4type
+*/
+#define P4_NOTUSED 0 /* The P4 parameter is not used */
+#define P4_DYNAMIC (-1) /* Pointer to a string obtained from sqliteMalloc() */
+#define P4_STATIC (-2) /* Pointer to a static string */
+#define P4_COLLSEQ (-4) /* P4 is a pointer to a CollSeq structure */
+#define P4_FUNCDEF (-5) /* P4 is a pointer to a FuncDef structure */
+#define P4_KEYINFO (-6) /* P4 is a pointer to a KeyInfo structure */
+#define P4_MEM (-8) /* P4 is a pointer to a Mem* structure */
+#define P4_TRANSIENT 0 /* P4 is a pointer to a transient string */
+#define P4_VTAB (-10) /* P4 is a pointer to an sqlite3_vtab structure */
+#define P4_MPRINTF (-11) /* P4 is a string obtained from sqlite3_mprintf() */
+#define P4_REAL (-12) /* P4 is a 64-bit floating point value */
+#define P4_INT64 (-13) /* P4 is a 64-bit signed integer */
+#define P4_INT32 (-14) /* P4 is a 32-bit signed integer */
+#define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
+#define P4_SUBPROGRAM (-18) /* P4 is a pointer to a SubProgram structure */
+#define P4_ADVANCE (-19) /* P4 is a pointer to BtreeNext() or BtreePrev() */
+
+/* Error message codes for OP_Halt */
+#define P5_ConstraintNotNull 1
+#define P5_ConstraintUnique 2
+#define P5_ConstraintCheck 3
+#define P5_ConstraintFK 4
+
+/*
+** The Vdbe.aColName array contains 5n Mem structures, where n is the
+** number of columns of data returned by the statement.
+*/
+#define COLNAME_NAME 0
+#define COLNAME_DECLTYPE 1
+#define COLNAME_DATABASE 2
+#define COLNAME_TABLE 3
+#define COLNAME_COLUMN 4
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+# define COLNAME_N 5 /* Number of COLNAME_xxx symbols */
+#else
+# ifdef SQLITE_OMIT_DECLTYPE
+# define COLNAME_N 1 /* Store only the name */
+# else
+# define COLNAME_N 2 /* Store the name and decltype */
+# endif
+#endif
+
+/*
+** The following macro converts a relative address in the p2 field
+** of a VdbeOp structure into a negative number so that
+** sqlite3VdbeAddOpList() knows that the address is relative. Calling
+** the macro again restores the address.
+*/
+#define ADDR(X) (-1-(X))
+
+/*
+** The makefile scans the vdbe.c source file and creates the "opcodes.h"
+** header file that defines a number for each opcode used by the VDBE.
+*/
+/************** Include opcodes.h in the middle of vdbe.h ********************/
+/************** Begin file opcodes.h *****************************************/
+/* Automatically generated. Do not edit */
+/* See the mkopcodeh.awk script for details */
+#define OP_Function 1 /* synopsis: r[P3]=func(r[P2@P5]) */
+#define OP_Savepoint 2
+#define OP_AutoCommit 3
+#define OP_Transaction 4
+#define OP_SorterNext 5
+#define OP_PrevIfOpen 6
+#define OP_NextIfOpen 7
+#define OP_Prev 8
+#define OP_Next 9
+#define OP_AggStep 10 /* synopsis: accum=r[P3] step(r[P2@P5]) */
+#define OP_Checkpoint 11
+#define OP_JournalMode 12
+#define OP_Vacuum 13
+#define OP_VFilter 14 /* synopsis: iplan=r[P3] zplan='P4' */
+#define OP_VUpdate 15 /* synopsis: data=r[P3@P2] */
+#define OP_Goto 16
+#define OP_Gosub 17
+#define OP_Return 18
+#define OP_Not 19 /* same as TK_NOT, synopsis: r[P2]= !r[P1] */
+#define OP_InitCoroutine 20
+#define OP_EndCoroutine 21
+#define OP_Yield 22
+#define OP_HaltIfNull 23 /* synopsis: if r[P3]=null halt */
+#define OP_Halt 24
+#define OP_Integer 25 /* synopsis: r[P2]=P1 */
+#define OP_Int64 26 /* synopsis: r[P2]=P4 */
+#define OP_String 27 /* synopsis: r[P2]='P4' (len=P1) */
+#define OP_Null 28 /* synopsis: r[P2..P3]=NULL */
+#define OP_SoftNull 29 /* synopsis: r[P1]=NULL */
+#define OP_Blob 30 /* synopsis: r[P2]=P4 (len=P1) */
+#define OP_Variable 31 /* synopsis: r[P2]=parameter(P1,P4) */
+#define OP_Move 32 /* synopsis: r[P2@P3]=r[P1@P3] */
+#define OP_Copy 33 /* synopsis: r[P2@P3+1]=r[P1@P3+1] */
+#define OP_SCopy 34 /* synopsis: r[P2]=r[P1] */
+#define OP_ResultRow 35 /* synopsis: output=r[P1@P2] */
+#define OP_CollSeq 36
+#define OP_AddImm 37 /* synopsis: r[P1]=r[P1]+P2 */
+#define OP_MustBeInt 38
+#define OP_RealAffinity 39
+#define OP_Permutation 40
+#define OP_Compare 41 /* synopsis: r[P1@P3] <-> r[P2@P3] */
+#define OP_Jump 42
+#define OP_Once 43
+#define OP_If 44
+#define OP_IfNot 45
+#define OP_Column 46 /* synopsis: r[P3]=PX */
+#define OP_Affinity 47 /* synopsis: affinity(r[P1@P2]) */
+#define OP_MakeRecord 48 /* synopsis: r[P3]=mkrec(r[P1@P2]) */
+#define OP_Count 49 /* synopsis: r[P2]=count() */
+#define OP_ReadCookie 50
+#define OP_SetCookie 51
+#define OP_OpenRead 52 /* synopsis: root=P2 iDb=P3 */
+#define OP_OpenWrite 53 /* synopsis: root=P2 iDb=P3 */
+#define OP_OpenAutoindex 54 /* synopsis: nColumn=P2 */
+#define OP_OpenEphemeral 55 /* synopsis: nColumn=P2 */
+#define OP_SorterOpen 56
+#define OP_OpenPseudo 57 /* synopsis: P3 columns in r[P2] */
+#define OP_Close 58
+#define OP_SeekLT 59
+#define OP_SeekLE 60
+#define OP_SeekGE 61
+#define OP_SeekGT 62
+#define OP_Seek 63 /* synopsis: intkey=r[P2] */
+#define OP_NoConflict 64 /* synopsis: key=r[P3@P4] */
+#define OP_NotFound 65 /* synopsis: key=r[P3@P4] */
+#define OP_Found 66 /* synopsis: key=r[P3@P4] */
+#define OP_NotExists 67 /* synopsis: intkey=r[P3] */
+#define OP_Sequence 68 /* synopsis: r[P2]=cursor[P1].ctr++ */
+#define OP_NewRowid 69 /* synopsis: r[P2]=rowid */
+#define OP_Insert 70 /* synopsis: intkey=r[P3] data=r[P2] */
+#define OP_Or 71 /* same as TK_OR, synopsis: r[P3]=(r[P1] || r[P2]) */
+#define OP_And 72 /* same as TK_AND, synopsis: r[P3]=(r[P1] && r[P2]) */
+#define OP_InsertInt 73 /* synopsis: intkey=P3 data=r[P2] */
+#define OP_Delete 74
+#define OP_ResetCount 75
+#define OP_IsNull 76 /* same as TK_ISNULL, synopsis: if r[P1]==NULL goto P2 */
+#define OP_NotNull 77 /* same as TK_NOTNULL, synopsis: if r[P1]!=NULL goto P2 */
+#define OP_Ne 78 /* same as TK_NE, synopsis: if r[P1]!=r[P3] goto P2 */
+#define OP_Eq 79 /* same as TK_EQ, synopsis: if r[P1]==r[P3] goto P2 */
+#define OP_Gt 80 /* same as TK_GT, synopsis: if r[P1]>r[P3] goto P2 */
+#define OP_Le 81 /* same as TK_LE, synopsis: if r[P1]<=r[P3] goto P2 */
+#define OP_Lt 82 /* same as TK_LT, synopsis: if r[P1]=r[P3] goto P2 */
+#define OP_SorterCompare 84 /* synopsis: if key(P1)!=rtrim(r[P3],P4) goto P2 */
+#define OP_BitAnd 85 /* same as TK_BITAND, synopsis: r[P3]=r[P1]&r[P2] */
+#define OP_BitOr 86 /* same as TK_BITOR, synopsis: r[P3]=r[P1]|r[P2] */
+#define OP_ShiftLeft 87 /* same as TK_LSHIFT, synopsis: r[P3]=r[P2]<>r[P1] */
+#define OP_Add 89 /* same as TK_PLUS, synopsis: r[P3]=r[P1]+r[P2] */
+#define OP_Subtract 90 /* same as TK_MINUS, synopsis: r[P3]=r[P2]-r[P1] */
+#define OP_Multiply 91 /* same as TK_STAR, synopsis: r[P3]=r[P1]*r[P2] */
+#define OP_Divide 92 /* same as TK_SLASH, synopsis: r[P3]=r[P2]/r[P1] */
+#define OP_Remainder 93 /* same as TK_REM, synopsis: r[P3]=r[P2]%r[P1] */
+#define OP_Concat 94 /* same as TK_CONCAT, synopsis: r[P3]=r[P2]+r[P1] */
+#define OP_SorterData 95 /* synopsis: r[P2]=data */
+#define OP_BitNot 96 /* same as TK_BITNOT, synopsis: r[P1]= ~r[P1] */
+#define OP_String8 97 /* same as TK_STRING, synopsis: r[P2]='P4' */
+#define OP_RowKey 98 /* synopsis: r[P2]=key */
+#define OP_RowData 99 /* synopsis: r[P2]=data */
+#define OP_Rowid 100 /* synopsis: r[P2]=rowid */
+#define OP_NullRow 101
+#define OP_Last 102
+#define OP_SorterSort 103
+#define OP_Sort 104
+#define OP_Rewind 105
+#define OP_SorterInsert 106
+#define OP_IdxInsert 107 /* synopsis: key=r[P2] */
+#define OP_IdxDelete 108 /* synopsis: key=r[P2@P3] */
+#define OP_IdxRowid 109 /* synopsis: r[P2]=rowid */
+#define OP_IdxLE 110 /* synopsis: key=r[P3@P4] */
+#define OP_IdxGT 111 /* synopsis: key=r[P3@P4] */
+#define OP_IdxLT 112 /* synopsis: key=r[P3@P4] */
+#define OP_IdxGE 113 /* synopsis: key=r[P3@P4] */
+#define OP_Destroy 114
+#define OP_Clear 115
+#define OP_ResetSorter 116
+#define OP_CreateIndex 117 /* synopsis: r[P2]=root iDb=P1 */
+#define OP_CreateTable 118 /* synopsis: r[P2]=root iDb=P1 */
+#define OP_ParseSchema 119
+#define OP_LoadAnalysis 120
+#define OP_DropTable 121
+#define OP_DropIndex 122
+#define OP_DropTrigger 123
+#define OP_IntegrityCk 124
+#define OP_RowSetAdd 125 /* synopsis: rowset(P1)=r[P2] */
+#define OP_RowSetRead 126 /* synopsis: r[P3]=rowset(P1) */
+#define OP_RowSetTest 127 /* synopsis: if r[P3] in rowset(P1) goto P2 */
+#define OP_Program 128
+#define OP_Param 129
+#define OP_FkCounter 130 /* synopsis: fkctr[P1]+=P2 */
+#define OP_FkIfZero 131 /* synopsis: if fkctr[P1]==0 goto P2 */
+#define OP_MemMax 132 /* synopsis: r[P1]=max(r[P1],r[P2]) */
+#define OP_Real 133 /* same as TK_FLOAT, synopsis: r[P2]=P4 */
+#define OP_IfPos 134 /* synopsis: if r[P1]>0 goto P2 */
+#define OP_IfNeg 135 /* synopsis: if r[P1]<0 goto P2 */
+#define OP_IfZero 136 /* synopsis: r[P1]+=P3, if r[P1]==0 goto P2 */
+#define OP_AggFinal 137 /* synopsis: accum=r[P1] N=P2 */
+#define OP_IncrVacuum 138
+#define OP_Expire 139
+#define OP_TableLock 140 /* synopsis: iDb=P1 root=P2 write=P3 */
+#define OP_VBegin 141
+#define OP_VCreate 142
+#define OP_ToText 143 /* same as TK_TO_TEXT */
+#define OP_ToBlob 144 /* same as TK_TO_BLOB */
+#define OP_ToNumeric 145 /* same as TK_TO_NUMERIC */
+#define OP_ToInt 146 /* same as TK_TO_INT */
+#define OP_ToReal 147 /* same as TK_TO_REAL */
+#define OP_VDestroy 148
+#define OP_VOpen 149
+#define OP_VColumn 150 /* synopsis: r[P3]=vcolumn(P2) */
+#define OP_VNext 151
+#define OP_VRename 152
+#define OP_Pagecount 153
+#define OP_MaxPgcnt 154
+#define OP_Init 155 /* synopsis: Start at P2 */
+#define OP_Noop 156
+#define OP_Explain 157
+
+
+/* Properties such as "out2" or "jump" that are specified in
+** comments following the "case" for each opcode in the vdbe.c
+** are encoded into bitvectors as follows:
+*/
+#define OPFLG_JUMP 0x0001 /* jump: P2 holds jmp target */
+#define OPFLG_OUT2_PRERELEASE 0x0002 /* out2-prerelease: */
+#define OPFLG_IN1 0x0004 /* in1: P1 is an input */
+#define OPFLG_IN2 0x0008 /* in2: P2 is an input */
+#define OPFLG_IN3 0x0010 /* in3: P3 is an input */
+#define OPFLG_OUT2 0x0020 /* out2: P2 is an output */
+#define OPFLG_OUT3 0x0040 /* out3: P3 is an output */
+#define OPFLG_INITIALIZER {\
+/* 0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01,\
+/* 8 */ 0x01, 0x01, 0x00, 0x00, 0x02, 0x00, 0x01, 0x00,\
+/* 16 */ 0x01, 0x01, 0x04, 0x24, 0x01, 0x04, 0x05, 0x10,\
+/* 24 */ 0x00, 0x02, 0x02, 0x02, 0x02, 0x00, 0x02, 0x02,\
+/* 32 */ 0x00, 0x00, 0x20, 0x00, 0x00, 0x04, 0x05, 0x04,\
+/* 40 */ 0x00, 0x00, 0x01, 0x01, 0x05, 0x05, 0x00, 0x00,\
+/* 48 */ 0x00, 0x02, 0x02, 0x10, 0x00, 0x00, 0x00, 0x00,\
+/* 56 */ 0x00, 0x00, 0x00, 0x11, 0x11, 0x11, 0x11, 0x08,\
+/* 64 */ 0x11, 0x11, 0x11, 0x11, 0x02, 0x02, 0x00, 0x4c,\
+/* 72 */ 0x4c, 0x00, 0x00, 0x00, 0x05, 0x05, 0x15, 0x15,\
+/* 80 */ 0x15, 0x15, 0x15, 0x15, 0x00, 0x4c, 0x4c, 0x4c,\
+/* 88 */ 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x00,\
+/* 96 */ 0x24, 0x02, 0x00, 0x00, 0x02, 0x00, 0x01, 0x01,\
+/* 104 */ 0x01, 0x01, 0x08, 0x08, 0x00, 0x02, 0x01, 0x01,\
+/* 112 */ 0x01, 0x01, 0x02, 0x00, 0x00, 0x02, 0x02, 0x00,\
+/* 120 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x0c, 0x45, 0x15,\
+/* 128 */ 0x01, 0x02, 0x00, 0x01, 0x08, 0x02, 0x05, 0x05,\
+/* 136 */ 0x05, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x04,\
+/* 144 */ 0x04, 0x04, 0x04, 0x04, 0x00, 0x00, 0x00, 0x01,\
+/* 152 */ 0x00, 0x02, 0x02, 0x01, 0x00, 0x00,}
+
+/************** End of opcodes.h *********************************************/
+/************** Continuing where we left off in vdbe.h ***********************/
+
+/*
+** Prototypes for the VDBE interface. See comments on the implementation
+** for a description of what each of these routines does.
+*/
+SQLITE_PRIVATE Vdbe *sqlite3VdbeCreate(Parse*);
+SQLITE_PRIVATE int sqlite3VdbeAddOp0(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp1(Vdbe*,int,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
+SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp, int iLineno);
+SQLITE_PRIVATE void sqlite3VdbeAddParseSchemaOp(Vdbe*,int,char*);
+SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe*, u32 addr, int P1);
+SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2);
+SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3);
+SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe*, u8 P5);
+SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
+SQLITE_PRIVATE void sqlite3VdbeChangeToNoop(Vdbe*, int addr);
+SQLITE_PRIVATE int sqlite3VdbeDeletePriorOpcode(Vdbe*, u8 op);
+SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
+SQLITE_PRIVATE void sqlite3VdbeSetP4KeyInfo(Parse*, Index*);
+SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe*, int);
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
+SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeClearObject(sqlite3*,Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,Parse*);
+SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
+SQLITE_PRIVATE int sqlite3VdbeCurrentAddr(Vdbe*);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3VdbeAssertMayAbort(Vdbe *, int);
+#endif
+SQLITE_PRIVATE void sqlite3VdbeResetStepResult(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeRewind(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
+SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe*);
+SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
+SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
+SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
+SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe*, int, u8);
+SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe*, int);
+#ifndef SQLITE_OMIT_TRACE
+SQLITE_PRIVATE char *sqlite3VdbeExpandSql(Vdbe*, const char*);
+#endif
+
+SQLITE_PRIVATE void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
+SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*,int);
+SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo *, char *, int, char **);
+
+typedef int (*RecordCompare)(int,const void*,UnpackedRecord*,int);
+SQLITE_PRIVATE RecordCompare sqlite3VdbeFindCompare(UnpackedRecord*);
+
+#ifndef SQLITE_OMIT_TRIGGER
+SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
+#endif
+
+/* Use SQLITE_ENABLE_COMMENTS to enable generation of extra comments on
+** each VDBE opcode.
+**
+** Use the SQLITE_ENABLE_MODULE_COMMENTS macro to see some extra no-op
+** comments in VDBE programs that show key decision points in the code
+** generator.
+*/
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
+SQLITE_PRIVATE void sqlite3VdbeComment(Vdbe*, const char*, ...);
+# define VdbeComment(X) sqlite3VdbeComment X
+SQLITE_PRIVATE void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
+# define VdbeNoopComment(X) sqlite3VdbeNoopComment X
+# ifdef SQLITE_ENABLE_MODULE_COMMENTS
+# define VdbeModuleComment(X) sqlite3VdbeNoopComment X
+# else
+# define VdbeModuleComment(X)
+# endif
+#else
+# define VdbeComment(X)
+# define VdbeNoopComment(X)
+# define VdbeModuleComment(X)
+#endif
+
+/*
+** The VdbeCoverage macros are used to set a coverage testing point
+** for VDBE branch instructions. The coverage testing points are line
+** numbers in the sqlite3.c source file. VDBE branch coverage testing
+** only works with an amalagmation build. That's ok since a VDBE branch
+** coverage build designed for testing the test suite only. No application
+** should ever ship with VDBE branch coverage measuring turned on.
+**
+** VdbeCoverage(v) // Mark the previously coded instruction
+** // as a branch
+**
+** VdbeCoverageIf(v, conditional) // Mark previous if conditional true
+**
+** VdbeCoverageAlwaysTaken(v) // Previous branch is always taken
+**
+** VdbeCoverageNeverTaken(v) // Previous branch is never taken
+**
+** Every VDBE branch operation must be tagged with one of the macros above.
+** If not, then when "make test" is run with -DSQLITE_VDBE_COVERAGE and
+** -DSQLITE_DEBUG then an ALWAYS() will fail in the vdbeTakeBranch()
+** routine in vdbe.c, alerting the developer to the missed tag.
+*/
+#ifdef SQLITE_VDBE_COVERAGE
+SQLITE_PRIVATE void sqlite3VdbeSetLineNumber(Vdbe*,int);
+# define VdbeCoverage(v) sqlite3VdbeSetLineNumber(v,__LINE__)
+# define VdbeCoverageIf(v,x) if(x)sqlite3VdbeSetLineNumber(v,__LINE__)
+# define VdbeCoverageAlwaysTaken(v) sqlite3VdbeSetLineNumber(v,2);
+# define VdbeCoverageNeverTaken(v) sqlite3VdbeSetLineNumber(v,1);
+# define VDBE_OFFSET_LINENO(x) (__LINE__+x)
+#else
+# define VdbeCoverage(v)
+# define VdbeCoverageIf(v,x)
+# define VdbeCoverageAlwaysTaken(v)
+# define VdbeCoverageNeverTaken(v)
+# define VDBE_OFFSET_LINENO(x) 0
+#endif
+
+#endif
+
+/************** End of vdbe.h ************************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include pager.h in the middle of sqliteInt.h *****************/
+/************** Begin file pager.h *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite page cache
+** subsystem. The page cache subsystem reads and writes a file a page
+** at a time and provides a journal for rollback.
+*/
+
+#ifndef _PAGER_H_
+#define _PAGER_H_
+
+/*
+** Default maximum size for persistent journal files. A negative
+** value means no limit. This value may be overridden using the
+** sqlite3PagerJournalSizeLimit() API. See also "PRAGMA journal_size_limit".
+*/
+#ifndef SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT
+ #define SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT -1
+#endif
+
+/*
+** The type used to represent a page number. The first page in a file
+** is called page 1. 0 is used to represent "not a page".
+*/
+typedef u32 Pgno;
+
+/*
+** Each open file is managed by a separate instance of the "Pager" structure.
+*/
+typedef struct Pager Pager;
+
+/*
+** Handle type for pages.
+*/
+typedef struct PgHdr DbPage;
+
+/*
+** Page number PAGER_MJ_PGNO is never used in an SQLite database (it is
+** reserved for working around a windows/posix incompatibility). It is
+** used in the journal to signify that the remainder of the journal file
+** is devoted to storing a master journal name - there are no more pages to
+** roll back. See comments for function writeMasterJournal() in pager.c
+** for details.
+*/
+#define PAGER_MJ_PGNO(x) ((Pgno)((PENDING_BYTE/((x)->pageSize))+1))
+
+/*
+** Allowed values for the flags parameter to sqlite3PagerOpen().
+**
+** NOTE: These values must match the corresponding BTREE_ values in btree.h.
+*/
+#define PAGER_OMIT_JOURNAL 0x0001 /* Do not use a rollback journal */
+#define PAGER_MEMORY 0x0002 /* In-memory database */
+
+/*
+** Valid values for the second argument to sqlite3PagerLockingMode().
+*/
+#define PAGER_LOCKINGMODE_QUERY -1
+#define PAGER_LOCKINGMODE_NORMAL 0
+#define PAGER_LOCKINGMODE_EXCLUSIVE 1
+
+/*
+** Numeric constants that encode the journalmode.
+*/
+#define PAGER_JOURNALMODE_QUERY (-1) /* Query the value of journalmode */
+#define PAGER_JOURNALMODE_DELETE 0 /* Commit by deleting journal file */
+#define PAGER_JOURNALMODE_PERSIST 1 /* Commit by zeroing journal header */
+#define PAGER_JOURNALMODE_OFF 2 /* Journal omitted. */
+#define PAGER_JOURNALMODE_TRUNCATE 3 /* Commit by truncating journal */
+#define PAGER_JOURNALMODE_MEMORY 4 /* In-memory journal file */
+#define PAGER_JOURNALMODE_WAL 5 /* Use write-ahead logging */
+
+/*
+** Flags that make up the mask passed to sqlite3PagerAcquire().
+*/
+#define PAGER_GET_NOCONTENT 0x01 /* Do not load data from disk */
+#define PAGER_GET_READONLY 0x02 /* Read-only page is acceptable */
+
+/*
+** Flags for sqlite3PagerSetFlags()
+*/
+#define PAGER_SYNCHRONOUS_OFF 0x01 /* PRAGMA synchronous=OFF */
+#define PAGER_SYNCHRONOUS_NORMAL 0x02 /* PRAGMA synchronous=NORMAL */
+#define PAGER_SYNCHRONOUS_FULL 0x03 /* PRAGMA synchronous=FULL */
+#define PAGER_SYNCHRONOUS_MASK 0x03 /* Mask for three values above */
+#define PAGER_FULLFSYNC 0x04 /* PRAGMA fullfsync=ON */
+#define PAGER_CKPT_FULLFSYNC 0x08 /* PRAGMA checkpoint_fullfsync=ON */
+#define PAGER_CACHESPILL 0x10 /* PRAGMA cache_spill=ON */
+#define PAGER_FLAGS_MASK 0x1c /* All above except SYNCHRONOUS */
+
+/*
+** The remainder of this file contains the declarations of the functions
+** that make up the Pager sub-system API. See source code comments for
+** a detailed description of each routine.
+*/
+
+/* Open and close a Pager connection. */
+SQLITE_PRIVATE int sqlite3PagerOpen(
+ sqlite3_vfs*,
+ Pager **ppPager,
+ const char*,
+ int,
+ int,
+ int,
+ void(*)(DbPage*)
+);
+SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager);
+SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);
+
+/* Functions used to configure a Pager object. */
+SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u32*, int);
+SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
+SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
+SQLITE_PRIVATE void sqlite3PagerSetMmapLimit(Pager *, sqlite3_int64);
+SQLITE_PRIVATE void sqlite3PagerShrink(Pager*);
+SQLITE_PRIVATE void sqlite3PagerSetFlags(Pager*,unsigned);
+SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
+SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *, int);
+SQLITE_PRIVATE int sqlite3PagerGetJournalMode(Pager*);
+SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager*);
+SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *, i64);
+SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager*);
+
+/* Functions used to obtain and release page references. */
+SQLITE_PRIVATE int sqlite3PagerAcquire(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);
+#define sqlite3PagerGet(A,B,C) sqlite3PagerAcquire(A,B,C,0)
+SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno);
+SQLITE_PRIVATE void sqlite3PagerRef(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerUnref(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerUnrefNotNull(DbPage*);
+
+/* Operations on page references. */
+SQLITE_PRIVATE int sqlite3PagerWrite(DbPage*);
+SQLITE_PRIVATE void sqlite3PagerDontWrite(DbPage*);
+SQLITE_PRIVATE int sqlite3PagerMovepage(Pager*,DbPage*,Pgno,int);
+SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage*);
+SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *);
+SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *);
+
+/* Functions used to manage pager transactions and savepoints. */
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager*, int*);
+SQLITE_PRIVATE int sqlite3PagerBegin(Pager*, int exFlag, int);
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager*);
+SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager, const char *zMaster);
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
+SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
+SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
+SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
+SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager);
+
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3PagerCheckpoint(Pager *pPager, int, int*, int*);
+SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager);
+SQLITE_PRIVATE int sqlite3PagerWalCallback(Pager *pPager);
+SQLITE_PRIVATE int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen);
+SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager);
+#endif
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+SQLITE_PRIVATE int sqlite3PagerWalFramesize(Pager *pPager);
+#endif
+
+/* Functions used to query pager state and configuration. */
+SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager*);
+SQLITE_PRIVATE int sqlite3PagerRefcount(Pager*);
+SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager*);
+SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager*, int);
+SQLITE_PRIVATE const sqlite3_vfs *sqlite3PagerVfs(Pager*);
+SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager*);
+SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager*);
+SQLITE_PRIVATE int sqlite3PagerNosync(Pager*);
+SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
+SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager*);
+SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *, int, int, int *);
+SQLITE_PRIVATE void sqlite3PagerClearCache(Pager *);
+SQLITE_PRIVATE int sqlite3SectorSize(sqlite3_file *);
+
+/* Functions used to truncate the database file. */
+SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager*,Pgno);
+
+#if defined(SQLITE_HAS_CODEC) && !defined(SQLITE_OMIT_WAL)
+SQLITE_PRIVATE void *sqlite3PagerCodec(DbPage *);
+#endif
+
+/* Functions to support testing and debugging. */
+#if !defined(NDEBUG) || defined(SQLITE_TEST)
+SQLITE_PRIVATE Pgno sqlite3PagerPagenumber(DbPage*);
+SQLITE_PRIVATE int sqlite3PagerIswriteable(DbPage*);
+#endif
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int *sqlite3PagerStats(Pager*);
+SQLITE_PRIVATE void sqlite3PagerRefdump(Pager*);
+ void disable_simulated_io_errors(void);
+ void enable_simulated_io_errors(void);
+#else
+# define disable_simulated_io_errors()
+# define enable_simulated_io_errors()
+#endif
+
+#endif /* _PAGER_H_ */
+
+/************** End of pager.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include pcache.h in the middle of sqliteInt.h ****************/
+/************** Begin file pcache.h ******************************************/
+/*
+** 2008 August 05
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the sqlite page cache
+** subsystem.
+*/
+
+#ifndef _PCACHE_H_
+
+typedef struct PgHdr PgHdr;
+typedef struct PCache PCache;
+
+/*
+** Every page in the cache is controlled by an instance of the following
+** structure.
+*/
+struct PgHdr {
+ sqlite3_pcache_page *pPage; /* Pcache object page handle */
+ void *pData; /* Page data */
+ void *pExtra; /* Extra content */
+ PgHdr *pDirty; /* Transient list of dirty pages */
+ Pager *pPager; /* The pager this page is part of */
+ Pgno pgno; /* Page number for this page */
+#ifdef SQLITE_CHECK_PAGES
+ u32 pageHash; /* Hash of page content */
+#endif
+ u16 flags; /* PGHDR flags defined below */
+
+ /**********************************************************************
+ ** Elements above are public. All that follows is private to pcache.c
+ ** and should not be accessed by other modules.
+ */
+ i16 nRef; /* Number of users of this page */
+ PCache *pCache; /* Cache that owns this page */
+
+ PgHdr *pDirtyNext; /* Next element in list of dirty pages */
+ PgHdr *pDirtyPrev; /* Previous element in list of dirty pages */
+};
+
+/* Bit values for PgHdr.flags */
+#define PGHDR_DIRTY 0x002 /* Page has changed */
+#define PGHDR_NEED_SYNC 0x004 /* Fsync the rollback journal before
+ ** writing this page to the database */
+#define PGHDR_NEED_READ 0x008 /* Content is unread */
+#define PGHDR_REUSE_UNLIKELY 0x010 /* A hint that reuse is unlikely */
+#define PGHDR_DONT_WRITE 0x020 /* Do not write content to disk */
+
+#define PGHDR_MMAP 0x040 /* This is an mmap page object */
+
+/* Initialize and shutdown the page cache subsystem */
+SQLITE_PRIVATE int sqlite3PcacheInitialize(void);
+SQLITE_PRIVATE void sqlite3PcacheShutdown(void);
+
+/* Page cache buffer management:
+** These routines implement SQLITE_CONFIG_PAGECACHE.
+*/
+SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *, int sz, int n);
+
+/* Create a new pager cache.
+** Under memory stress, invoke xStress to try to make pages clean.
+** Only clean and unpinned pages can be reclaimed.
+*/
+SQLITE_PRIVATE void sqlite3PcacheOpen(
+ int szPage, /* Size of every page */
+ int szExtra, /* Extra space associated with each page */
+ int bPurgeable, /* True if pages are on backing store */
+ int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
+ void *pStress, /* Argument to xStress */
+ PCache *pToInit /* Preallocated space for the PCache */
+);
+
+/* Modify the page-size after the cache has been created. */
+SQLITE_PRIVATE void sqlite3PcacheSetPageSize(PCache *, int);
+
+/* Return the size in bytes of a PCache object. Used to preallocate
+** storage space.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSize(void);
+
+/* One release per successful fetch. Page is pinned until released.
+** Reference counted.
+*/
+SQLITE_PRIVATE int sqlite3PcacheFetch(PCache*, Pgno, int createFlag, PgHdr**);
+SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr*);
+
+SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr*); /* Remove page from cache */
+SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr*); /* Make sure page is marked dirty */
+SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr*); /* Mark a single page as clean */
+SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache*); /* Mark all dirty list pages as clean */
+
+/* Change a page number. Used by incr-vacuum. */
+SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr*, Pgno);
+
+/* Remove all pages with pgno>x. Reset the cache if x==0 */
+SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache*, Pgno x);
+
+/* Get a list of all dirty pages in the cache, sorted by page number */
+SQLITE_PRIVATE PgHdr *sqlite3PcacheDirtyList(PCache*);
+
+/* Reset and close the cache object */
+SQLITE_PRIVATE void sqlite3PcacheClose(PCache*);
+
+/* Clear flags from pages of the page cache */
+SQLITE_PRIVATE void sqlite3PcacheClearSyncFlags(PCache *);
+
+/* Discard the contents of the cache */
+SQLITE_PRIVATE void sqlite3PcacheClear(PCache*);
+
+/* Return the total number of outstanding page references */
+SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache*);
+
+/* Increment the reference count of an existing page */
+SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr*);
+
+SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr*);
+
+/* Return the total number of pages stored in the cache */
+SQLITE_PRIVATE int sqlite3PcachePagecount(PCache*);
+
+#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
+/* Iterate through all dirty pages currently stored in the cache. This
+** interface is only available if SQLITE_CHECK_PAGES is defined when the
+** library is built.
+*/
+SQLITE_PRIVATE void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *));
+#endif
+
+/* Set and get the suggested cache-size for the specified pager-cache.
+**
+** If no global maximum is configured, then the system attempts to limit
+** the total number of pages cached by purgeable pager-caches to the sum
+** of the suggested cache-sizes.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *, int);
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *);
+#endif
+
+/* Free up as much memory as possible from the page cache */
+SQLITE_PRIVATE void sqlite3PcacheShrink(PCache*);
+
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/* Try to return memory used by the pcache module to the main memory heap */
+SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int);
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE void sqlite3PcacheStats(int*,int*,int*,int*);
+#endif
+
+SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
+
+#endif /* _PCACHE_H_ */
+
+/************** End of pcache.h **********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+
+/************** Include os.h in the middle of sqliteInt.h ********************/
+/************** Begin file os.h **********************************************/
+/*
+** 2001 September 16
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This header file (together with is companion C source-code file
+** "os.c") attempt to abstract the underlying operating system so that
+** the SQLite library will work on both POSIX and windows systems.
+**
+** This header file is #include-ed by sqliteInt.h and thus ends up
+** being included by every source file.
+*/
+#ifndef _SQLITE_OS_H_
+#define _SQLITE_OS_H_
+
+/*
+** Attempt to automatically detect the operating system and setup the
+** necessary pre-processor macros for it.
+*/
+/************** Include os_setup.h in the middle of os.h *********************/
+/************** Begin file os_setup.h ****************************************/
+/*
+** 2013 November 25
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains pre-processor directives related to operating system
+** detection and/or setup.
+*/
+#ifndef _OS_SETUP_H_
+#define _OS_SETUP_H_
+
+/*
+** Figure out if we are dealing with Unix, Windows, or some other operating
+** system.
+**
+** After the following block of preprocess macros, all of SQLITE_OS_UNIX,
+** SQLITE_OS_WIN, and SQLITE_OS_OTHER will defined to either 1 or 0. One of
+** the three will be 1. The other two will be 0.
+*/
+#if defined(SQLITE_OS_OTHER)
+# if SQLITE_OS_OTHER==1
+# undef SQLITE_OS_UNIX
+# define SQLITE_OS_UNIX 0
+# undef SQLITE_OS_WIN
+# define SQLITE_OS_WIN 0
+# else
+# undef SQLITE_OS_OTHER
+# endif
+#endif
+#if !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_OTHER)
+# define SQLITE_OS_OTHER 0
+# ifndef SQLITE_OS_WIN
+# if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || \
+ defined(__MINGW32__) || defined(__BORLANDC__)
+# define SQLITE_OS_WIN 1
+# define SQLITE_OS_UNIX 0
+# else
+# define SQLITE_OS_WIN 0
+# define SQLITE_OS_UNIX 1
+# endif
+# else
+# define SQLITE_OS_UNIX 0
+# endif
+#else
+# ifndef SQLITE_OS_WIN
+# define SQLITE_OS_WIN 0
+# endif
+#endif
+
+#endif /* _OS_SETUP_H_ */
+
+/************** End of os_setup.h ********************************************/
+/************** Continuing where we left off in os.h *************************/
+
+/* If the SET_FULLSYNC macro is not defined above, then make it
+** a no-op
+*/
+#ifndef SET_FULLSYNC
+# define SET_FULLSYNC(x,y)
+#endif
+
+/*
+** The default size of a disk sector
+*/
+#ifndef SQLITE_DEFAULT_SECTOR_SIZE
+# define SQLITE_DEFAULT_SECTOR_SIZE 4096
+#endif
+
+/*
+** Temporary files are named starting with this prefix followed by 16 random
+** alphanumeric characters, and no file extension. They are stored in the
+** OS's standard temporary file directory, and are deleted prior to exit.
+** If sqlite is being embedded in another program, you may wish to change the
+** prefix to reflect your program's name, so that if your program exits
+** prematurely, old temporary files can be easily identified. This can be done
+** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
+**
+** 2006-10-31: The default prefix used to be "sqlite_". But then
+** Mcafee started using SQLite in their anti-virus product and it
+** started putting files with the "sqlite" name in the c:/temp folder.
+** This annoyed many windows users. Those users would then do a
+** Google search for "sqlite", find the telephone numbers of the
+** developers and call to wake them up at night and complain.
+** For this reason, the default name prefix is changed to be "sqlite"
+** spelled backwards. So the temp files are still identified, but
+** anybody smart enough to figure out the code is also likely smart
+** enough to know that calling the developer will not help get rid
+** of the file.
+*/
+#ifndef SQLITE_TEMP_FILE_PREFIX
+# define SQLITE_TEMP_FILE_PREFIX "etilqs_"
+#endif
+
+/*
+** The following values may be passed as the second argument to
+** sqlite3OsLock(). The various locks exhibit the following semantics:
+**
+** SHARED: Any number of processes may hold a SHARED lock simultaneously.
+** RESERVED: A single process may hold a RESERVED lock on a file at
+** any time. Other processes may hold and obtain new SHARED locks.
+** PENDING: A single process may hold a PENDING lock on a file at
+** any one time. Existing SHARED locks may persist, but no new
+** SHARED locks may be obtained by other processes.
+** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks.
+**
+** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a
+** process that requests an EXCLUSIVE lock may actually obtain a PENDING
+** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to
+** sqlite3OsLock().
+*/
+#define NO_LOCK 0
+#define SHARED_LOCK 1
+#define RESERVED_LOCK 2
+#define PENDING_LOCK 3
+#define EXCLUSIVE_LOCK 4
+
+/*
+** File Locking Notes: (Mostly about windows but also some info for Unix)
+**
+** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
+** those functions are not available. So we use only LockFile() and
+** UnlockFile().
+**
+** LockFile() prevents not just writing but also reading by other processes.
+** A SHARED_LOCK is obtained by locking a single randomly-chosen
+** byte out of a specific range of bytes. The lock byte is obtained at
+** random so two separate readers can probably access the file at the
+** same time, unless they are unlucky and choose the same lock byte.
+** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range.
+** There can only be one writer. A RESERVED_LOCK is obtained by locking
+** a single byte of the file that is designated as the reserved lock byte.
+** A PENDING_LOCK is obtained by locking a designated byte different from
+** the RESERVED_LOCK byte.
+**
+** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
+** which means we can use reader/writer locks. When reader/writer locks
+** are used, the lock is placed on the same range of bytes that is used
+** for probabilistic locking in Win95/98/ME. Hence, the locking scheme
+** will support two or more Win95 readers or two or more WinNT readers.
+** But a single Win95 reader will lock out all WinNT readers and a single
+** WinNT reader will lock out all other Win95 readers.
+**
+** The following #defines specify the range of bytes used for locking.
+** SHARED_SIZE is the number of bytes available in the pool from which
+** a random byte is selected for a shared lock. The pool of bytes for
+** shared locks begins at SHARED_FIRST.
+**
+** The same locking strategy and
+** byte ranges are used for Unix. This leaves open the possiblity of having
+** clients on win95, winNT, and unix all talking to the same shared file
+** and all locking correctly. To do so would require that samba (or whatever
+** tool is being used for file sharing) implements locks correctly between
+** windows and unix. I'm guessing that isn't likely to happen, but by
+** using the same locking range we are at least open to the possibility.
+**
+** Locking in windows is manditory. For this reason, we cannot store
+** actual data in the bytes used for locking. The pager never allocates
+** the pages involved in locking therefore. SHARED_SIZE is selected so
+** that all locks will fit on a single page even at the minimum page size.
+** PENDING_BYTE defines the beginning of the locks. By default PENDING_BYTE
+** is set high so that we don't have to allocate an unused page except
+** for very large databases. But one should test the page skipping logic
+** by setting PENDING_BYTE low and running the entire regression suite.
+**
+** Changing the value of PENDING_BYTE results in a subtly incompatible
+** file format. Depending on how it is changed, you might not notice
+** the incompatibility right away, even running a full regression test.
+** The default location of PENDING_BYTE is the first byte past the
+** 1GB boundary.
+**
+*/
+#ifdef SQLITE_OMIT_WSD
+# define PENDING_BYTE (0x40000000)
+#else
+# define PENDING_BYTE sqlite3PendingByte
+#endif
+#define RESERVED_BYTE (PENDING_BYTE+1)
+#define SHARED_FIRST (PENDING_BYTE+2)
+#define SHARED_SIZE 510
+
+/*
+** Wrapper around OS specific sqlite3_os_init() function.
+*/
+SQLITE_PRIVATE int sqlite3OsInit(void);
+
+/*
+** Functions for accessing sqlite3_file methods
+*/
+SQLITE_PRIVATE int sqlite3OsClose(sqlite3_file*);
+SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
+SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
+SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file*, i64 size);
+SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file*, int);
+SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
+SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file*, int);
+SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file*, int);
+SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut);
+SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file*,int,void*);
+SQLITE_PRIVATE void sqlite3OsFileControlHint(sqlite3_file*,int,void*);
+#define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
+SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
+SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
+SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int);
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64, int, void **);
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *, i64, void *);
+
+
+/*
+** Functions for accessing sqlite3_vfs methods
+*/
+SQLITE_PRIVATE int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
+SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
+SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut);
+SQLITE_PRIVATE int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
+SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *, int, char *);
+SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *, void *, const char *))(void);
+SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *, void *);
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
+SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
+SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *, int);
+SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *, sqlite3_int64*);
+
+/*
+** Convenience functions for opening and closing files using
+** sqlite3_malloc() to obtain space for the file-handle structure.
+*/
+SQLITE_PRIVATE int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
+SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *);
+
+#endif /* _SQLITE_OS_H_ */
+
+/************** End of os.h **************************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+/************** Include mutex.h in the middle of sqliteInt.h *****************/
+/************** Begin file mutex.h *******************************************/
+/*
+** 2007 August 28
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains the common header for all mutex implementations.
+** The sqliteInt.h header #includes this file so that it is available
+** to all source files. We break it out in an effort to keep the code
+** better organized.
+**
+** NOTE: source files should *not* #include this header file directly.
+** Source files should #include the sqliteInt.h file and let that file
+** include this one indirectly.
+*/
+
+
+/*
+** Figure out what version of the code to use. The choices are
+**
+** SQLITE_MUTEX_OMIT No mutex logic. Not even stubs. The
+** mutexes implemention cannot be overridden
+** at start-time.
+**
+** SQLITE_MUTEX_NOOP For single-threaded applications. No
+** mutual exclusion is provided. But this
+** implementation can be overridden at
+** start-time.
+**
+** SQLITE_MUTEX_PTHREADS For multi-threaded applications on Unix.
+**
+** SQLITE_MUTEX_W32 For multi-threaded applications on Win32.
+*/
+#if !SQLITE_THREADSAFE
+# define SQLITE_MUTEX_OMIT
+#endif
+#if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP)
+# if SQLITE_OS_UNIX
+# define SQLITE_MUTEX_PTHREADS
+# elif SQLITE_OS_WIN
+# define SQLITE_MUTEX_W32
+# else
+# define SQLITE_MUTEX_NOOP
+# endif
+#endif
+
+#ifdef SQLITE_MUTEX_OMIT
+/*
+** If this is a no-op implementation, implement everything as macros.
+*/
+#define sqlite3_mutex_alloc(X) ((sqlite3_mutex*)8)
+#define sqlite3_mutex_free(X)
+#define sqlite3_mutex_enter(X)
+#define sqlite3_mutex_try(X) SQLITE_OK
+#define sqlite3_mutex_leave(X)
+#define sqlite3_mutex_held(X) ((void)(X),1)
+#define sqlite3_mutex_notheld(X) ((void)(X),1)
+#define sqlite3MutexAlloc(X) ((sqlite3_mutex*)8)
+#define sqlite3MutexInit() SQLITE_OK
+#define sqlite3MutexEnd()
+#define MUTEX_LOGIC(X)
+#else
+#define MUTEX_LOGIC(X) X
+#endif /* defined(SQLITE_MUTEX_OMIT) */
+
+/************** End of mutex.h ***********************************************/
+/************** Continuing where we left off in sqliteInt.h ******************/
+
+
+/*
+** Each database file to be accessed by the system is an instance
+** of the following structure. There are normally two of these structures
+** in the sqlite.aDb[] array. aDb[0] is the main database file and
+** aDb[1] is the database file used to hold temporary tables. Additional
+** databases may be attached.
+*/
+struct Db {
+ char *zName; /* Name of this database */
+ Btree *pBt; /* The B*Tree structure for this database file */
+ u8 safety_level; /* How aggressive at syncing data to disk */
+ Schema *pSchema; /* Pointer to database schema (possibly shared) */
+};
+
+/*
+** An instance of the following structure stores a database schema.
+**
+** Most Schema objects are associated with a Btree. The exception is
+** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.
+** In shared cache mode, a single Schema object can be shared by multiple
+** Btrees that refer to the same underlying BtShared object.
+**
+** Schema objects are automatically deallocated when the last Btree that
+** references them is destroyed. The TEMP Schema is manually freed by
+** sqlite3_close().
+*
+** A thread must be holding a mutex on the corresponding Btree in order
+** to access Schema content. This implies that the thread must also be
+** holding a mutex on the sqlite3 connection pointer that owns the Btree.
+** For a TEMP Schema, only the connection mutex is required.
+*/
+struct Schema {
+ int schema_cookie; /* Database schema version number for this file */
+ int iGeneration; /* Generation counter. Incremented with each change */
+ Hash tblHash; /* All tables indexed by name */
+ Hash idxHash; /* All (named) indices indexed by name */
+ Hash trigHash; /* All triggers indexed by name */
+ Hash fkeyHash; /* All foreign keys by referenced table name */
+ Table *pSeqTab; /* The sqlite_sequence table used by AUTOINCREMENT */
+ u8 file_format; /* Schema format version for this file */
+ u8 enc; /* Text encoding used by this database */
+ u16 flags; /* Flags associated with this schema */
+ int cache_size; /* Number of pages to use in the cache */
+};
+
+/*
+** These macros can be used to test, set, or clear bits in the
+** Db.pSchema->flags field.
+*/
+#define DbHasProperty(D,I,P) (((D)->aDb[I].pSchema->flags&(P))==(P))
+#define DbHasAnyProperty(D,I,P) (((D)->aDb[I].pSchema->flags&(P))!=0)
+#define DbSetProperty(D,I,P) (D)->aDb[I].pSchema->flags|=(P)
+#define DbClearProperty(D,I,P) (D)->aDb[I].pSchema->flags&=~(P)
+
+/*
+** Allowed values for the DB.pSchema->flags field.
+**
+** The DB_SchemaLoaded flag is set after the database schema has been
+** read into internal hash tables.
+**
+** DB_UnresetViews means that one or more views have column names that
+** have been filled out. If the schema changes, these column names might
+** changes and so the view will need to be reset.
+*/
+#define DB_SchemaLoaded 0x0001 /* The schema has been loaded */
+#define DB_UnresetViews 0x0002 /* Some views have defined column names */
+#define DB_Empty 0x0004 /* The file is empty (length 0 bytes) */
+
+/*
+** The number of different kinds of things that can be limited
+** using the sqlite3_limit() interface.
+*/
+#define SQLITE_N_LIMIT (SQLITE_LIMIT_TRIGGER_DEPTH+1)
+
+/*
+** Lookaside malloc is a set of fixed-size buffers that can be used
+** to satisfy small transient memory allocation requests for objects
+** associated with a particular database connection. The use of
+** lookaside malloc provides a significant performance enhancement
+** (approx 10%) by avoiding numerous malloc/free requests while parsing
+** SQL statements.
+**
+** The Lookaside structure holds configuration information about the
+** lookaside malloc subsystem. Each available memory allocation in
+** the lookaside subsystem is stored on a linked list of LookasideSlot
+** objects.
+**
+** Lookaside allocations are only allowed for objects that are associated
+** with a particular database connection. Hence, schema information cannot
+** be stored in lookaside because in shared cache mode the schema information
+** is shared by multiple database connections. Therefore, while parsing
+** schema information, the Lookaside.bEnabled flag is cleared so that
+** lookaside allocations are not used to construct the schema objects.
+*/
+struct Lookaside {
+ u16 sz; /* Size of each buffer in bytes */
+ u8 bEnabled; /* False to disable new lookaside allocations */
+ u8 bMalloced; /* True if pStart obtained from sqlite3_malloc() */
+ int nOut; /* Number of buffers currently checked out */
+ int mxOut; /* Highwater mark for nOut */
+ int anStat[3]; /* 0: hits. 1: size misses. 2: full misses */
+ LookasideSlot *pFree; /* List of available buffers */
+ void *pStart; /* First byte of available memory space */
+ void *pEnd; /* First byte past end of available space */
+};
+struct LookasideSlot {
+ LookasideSlot *pNext; /* Next buffer in the list of free buffers */
+};
+
+/*
+** A hash table for function definitions.
+**
+** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
+** Collisions are on the FuncDef.pHash chain.
+*/
+struct FuncDefHash {
+ FuncDef *a[23]; /* Hash table for functions */
+};
+
+/*
+** Each database connection is an instance of the following structure.
+*/
+struct sqlite3 {
+ sqlite3_vfs *pVfs; /* OS Interface */
+ struct Vdbe *pVdbe; /* List of active virtual machines */
+ CollSeq *pDfltColl; /* The default collating sequence (BINARY) */
+ sqlite3_mutex *mutex; /* Connection mutex */
+ Db *aDb; /* All backends */
+ int nDb; /* Number of backends currently in use */
+ int flags; /* Miscellaneous flags. See below */
+ i64 lastRowid; /* ROWID of most recent insert (see above) */
+ i64 szMmap; /* Default mmap_size setting */
+ unsigned int openFlags; /* Flags passed to sqlite3_vfs.xOpen() */
+ int errCode; /* Most recent error code (SQLITE_*) */
+ int errMask; /* & result codes with this before returning */
+ u16 dbOptFlags; /* Flags to enable/disable optimizations */
+ u8 autoCommit; /* The auto-commit flag. */
+ u8 temp_store; /* 1: file 2: memory 0: default */
+ u8 mallocFailed; /* True if we have seen a malloc failure */
+ u8 dfltLockMode; /* Default locking-mode for attached dbs */
+ signed char nextAutovac; /* Autovac setting after VACUUM if >=0 */
+ u8 suppressErr; /* Do not issue error messages if true */
+ u8 vtabOnConflict; /* Value to return for s3_vtab_on_conflict() */
+ u8 isTransactionSavepoint; /* True if the outermost savepoint is a TS */
+ int nextPagesize; /* Pagesize after VACUUM if >0 */
+ u32 magic; /* Magic number for detect library misuse */
+ int nChange; /* Value returned by sqlite3_changes() */
+ int nTotalChange; /* Value returned by sqlite3_total_changes() */
+ int aLimit[SQLITE_N_LIMIT]; /* Limits */
+ struct sqlite3InitInfo { /* Information used during initialization */
+ int newTnum; /* Rootpage of table being initialized */
+ u8 iDb; /* Which db file is being initialized */
+ u8 busy; /* TRUE if currently initializing */
+ u8 orphanTrigger; /* Last statement is orphaned TEMP trigger */
+ } init;
+ int nVdbeActive; /* Number of VDBEs currently running */
+ int nVdbeRead; /* Number of active VDBEs that read or write */
+ int nVdbeWrite; /* Number of active VDBEs that read and write */
+ int nVdbeExec; /* Number of nested calls to VdbeExec() */
+ int nExtension; /* Number of loaded extensions */
+ void **aExtension; /* Array of shared library handles */
+ void (*xTrace)(void*,const char*); /* Trace function */
+ void *pTraceArg; /* Argument to the trace function */
+ void (*xProfile)(void*,const char*,u64); /* Profiling function */
+ void *pProfileArg; /* Argument to profile function */
+ void *pCommitArg; /* Argument to xCommitCallback() */
+ int (*xCommitCallback)(void*); /* Invoked at every commit. */
+ void *pRollbackArg; /* Argument to xRollbackCallback() */
+ void (*xRollbackCallback)(void*); /* Invoked at every commit. */
+ void *pUpdateArg;
+ void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
+#ifndef SQLITE_OMIT_WAL
+ int (*xWalCallback)(void *, sqlite3 *, const char *, int);
+ void *pWalArg;
+#endif
+ void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
+ void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
+ void *pCollNeededArg;
+ sqlite3_value *pErr; /* Most recent error message */
+ union {
+ volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
+ double notUsed1; /* Spacer */
+ } u1;
+ Lookaside lookaside; /* Lookaside malloc configuration */
+#ifndef SQLITE_OMIT_AUTHORIZATION
+ int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
+ /* Access authorization function */
+ void *pAuthArg; /* 1st argument to the access auth function */
+#endif
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+ int (*xProgress)(void *); /* The progress callback */
+ void *pProgressArg; /* Argument to the progress callback */
+ unsigned nProgressOps; /* Number of opcodes for progress callback */
+#endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ int nVTrans; /* Allocated size of aVTrans */
+ Hash aModule; /* populated by sqlite3_create_module() */
+ VtabCtx *pVtabCtx; /* Context for active vtab connect/create */
+ VTable **aVTrans; /* Virtual tables with open transactions */
+ VTable *pDisconnect; /* Disconnect these in next sqlite3_prepare() */
+#endif
+ FuncDefHash aFunc; /* Hash table of connection functions */
+ Hash aCollSeq; /* All collating sequences */
+ BusyHandler busyHandler; /* Busy callback */
+ Db aDbStatic[2]; /* Static space for the 2 default backends */
+ Savepoint *pSavepoint; /* List of active savepoints */
+ int busyTimeout; /* Busy handler timeout, in msec */
+ int nSavepoint; /* Number of non-transaction savepoints */
+ int nStatement; /* Number of nested statement-transactions */
+ i64 nDeferredCons; /* Net deferred constraints this transaction. */
+ i64 nDeferredImmCons; /* Net deferred immediate constraints */
+ int *pnBytesFreed; /* If not NULL, increment this in DbFree() */
+
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+ /* The following variables are all protected by the STATIC_MASTER
+ ** mutex, not by sqlite3.mutex. They are used by code in notify.c.
+ **
+ ** When X.pUnlockConnection==Y, that means that X is waiting for Y to
+ ** unlock so that it can proceed.
+ **
+ ** When X.pBlockingConnection==Y, that means that something that X tried
+ ** tried to do recently failed with an SQLITE_LOCKED error due to locks
+ ** held by Y.
+ */
+ sqlite3 *pBlockingConnection; /* Connection that caused SQLITE_LOCKED */
+ sqlite3 *pUnlockConnection; /* Connection to watch for unlock */
+ void *pUnlockArg; /* Argument to xUnlockNotify */
+ void (*xUnlockNotify)(void **, int); /* Unlock notify callback */
+ sqlite3 *pNextBlocked; /* Next in list of all blocked connections */
+#endif
+};
+
+/*
+** A macro to discover the encoding of a database.
+*/
+#define ENC(db) ((db)->aDb[0].pSchema->enc)
+
+/*
+** Possible values for the sqlite3.flags.
+*/
+#define SQLITE_VdbeTrace 0x00000001 /* True to trace VDBE execution */
+#define SQLITE_InternChanges 0x00000002 /* Uncommitted Hash table changes */
+#define SQLITE_FullFSync 0x00000004 /* Use full fsync on the backend */
+#define SQLITE_CkptFullFSync 0x00000008 /* Use full fsync for checkpoint */
+#define SQLITE_CacheSpill 0x00000010 /* OK to spill pager cache */
+#define SQLITE_FullColNames 0x00000020 /* Show full column names on SELECT */
+#define SQLITE_ShortColNames 0x00000040 /* Show short columns names */
+#define SQLITE_CountRows 0x00000080 /* Count rows changed by INSERT, */
+ /* DELETE, or UPDATE and return */
+ /* the count using a callback. */
+#define SQLITE_NullCallback 0x00000100 /* Invoke the callback once if the */
+ /* result set is empty */
+#define SQLITE_SqlTrace 0x00000200 /* Debug print SQL as it executes */
+#define SQLITE_VdbeListing 0x00000400 /* Debug listings of VDBE programs */
+#define SQLITE_WriteSchema 0x00000800 /* OK to update SQLITE_MASTER */
+#define SQLITE_VdbeAddopTrace 0x00001000 /* Trace sqlite3VdbeAddOp() calls */
+#define SQLITE_IgnoreChecks 0x00002000 /* Do not enforce check constraints */
+#define SQLITE_ReadUncommitted 0x0004000 /* For shared-cache mode */
+#define SQLITE_LegacyFileFmt 0x00008000 /* Create new databases in format 1 */
+#define SQLITE_RecoveryMode 0x00010000 /* Ignore schema errors */
+#define SQLITE_ReverseOrder 0x00020000 /* Reverse unordered SELECTs */
+#define SQLITE_RecTriggers 0x00040000 /* Enable recursive triggers */
+#define SQLITE_ForeignKeys 0x00080000 /* Enforce foreign key constraints */
+#define SQLITE_AutoIndex 0x00100000 /* Enable automatic indexes */
+#define SQLITE_PreferBuiltin 0x00200000 /* Preference to built-in funcs */
+#define SQLITE_LoadExtension 0x00400000 /* Enable load_extension */
+#define SQLITE_EnableTrigger 0x00800000 /* True to enable triggers */
+#define SQLITE_DeferFKs 0x01000000 /* Defer all FK constraints */
+#define SQLITE_QueryOnly 0x02000000 /* Disable database changes */
+#define SQLITE_VdbeEQP 0x04000000 /* Debug EXPLAIN QUERY PLAN */
+
+
+/*
+** Bits of the sqlite3.dbOptFlags field that are used by the
+** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
+** selectively disable various optimizations.
+*/
+#define SQLITE_QueryFlattener 0x0001 /* Query flattening */
+#define SQLITE_ColumnCache 0x0002 /* Column cache */
+#define SQLITE_GroupByOrder 0x0004 /* GROUPBY cover of ORDERBY */
+#define SQLITE_FactorOutConst 0x0008 /* Constant factoring */
+/* not used 0x0010 // Was: SQLITE_IdxRealAsInt */
+#define SQLITE_DistinctOpt 0x0020 /* DISTINCT using indexes */
+#define SQLITE_CoverIdxScan 0x0040 /* Covering index scans */
+#define SQLITE_OrderByIdxJoin 0x0080 /* ORDER BY of joins via index */
+#define SQLITE_SubqCoroutine 0x0100 /* Evaluate subqueries as coroutines */
+#define SQLITE_Transitive 0x0200 /* Transitive constraints */
+#define SQLITE_OmitNoopJoin 0x0400 /* Omit unused tables in joins */
+#define SQLITE_Stat3 0x0800 /* Use the SQLITE_STAT3 table */
+#define SQLITE_AdjustOutEst 0x1000 /* Adjust output estimates using WHERE */
+#define SQLITE_AllOpts 0xffff /* All optimizations */
+
+/*
+** Macros for testing whether or not optimizations are enabled or disabled.
+*/
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+#define OptimizationDisabled(db, mask) (((db)->dbOptFlags&(mask))!=0)
+#define OptimizationEnabled(db, mask) (((db)->dbOptFlags&(mask))==0)
+#else
+#define OptimizationDisabled(db, mask) 0
+#define OptimizationEnabled(db, mask) 1
+#endif
+
+/*
+** Return true if it OK to factor constant expressions into the initialization
+** code. The argument is a Parse object for the code generator.
+*/
+#define ConstFactorOk(P) ((P)->okConstFactor)
+
+/*
+** Possible values for the sqlite.magic field.
+** The numbers are obtained at random and have no special meaning, other
+** than being distinct from one another.
+*/
+#define SQLITE_MAGIC_OPEN 0xa029a697 /* Database is open */
+#define SQLITE_MAGIC_CLOSED 0x9f3c2d33 /* Database is closed */
+#define SQLITE_MAGIC_SICK 0x4b771290 /* Error and awaiting close */
+#define SQLITE_MAGIC_BUSY 0xf03b7906 /* Database currently in use */
+#define SQLITE_MAGIC_ERROR 0xb5357930 /* An SQLITE_MISUSE error occurred */
+#define SQLITE_MAGIC_ZOMBIE 0x64cffc7f /* Close with last statement close */
+
+/*
+** Each SQL function is defined by an instance of the following
+** structure. A pointer to this structure is stored in the sqlite.aFunc
+** hash table. When multiple functions have the same name, the hash table
+** points to a linked list of these structures.
+*/
+struct FuncDef {
+ i16 nArg; /* Number of arguments. -1 means unlimited */
+ u16 funcFlags; /* Some combination of SQLITE_FUNC_* */
+ void *pUserData; /* User data parameter */
+ FuncDef *pNext; /* Next function with same name */
+ void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
+ void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
+ void (*xFinalize)(sqlite3_context*); /* Aggregate finalizer */
+ char *zName; /* SQL name of the function. */
+ FuncDef *pHash; /* Next with a different name but the same hash */
+ FuncDestructor *pDestructor; /* Reference counted destructor function */
+};
+
+/*
+** This structure encapsulates a user-function destructor callback (as
+** configured using create_function_v2()) and a reference counter. When
+** create_function_v2() is called to create a function with a destructor,
+** a single object of this type is allocated. FuncDestructor.nRef is set to
+** the number of FuncDef objects created (either 1 or 3, depending on whether
+** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
+** member of each of the new FuncDef objects is set to point to the allocated
+** FuncDestructor.
+**
+** Thereafter, when one of the FuncDef objects is deleted, the reference
+** count on this object is decremented. When it reaches 0, the destructor
+** is invoked and the FuncDestructor structure freed.
+*/
+struct FuncDestructor {
+ int nRef;
+ void (*xDestroy)(void *);
+ void *pUserData;
+};
+
+/*
+** Possible values for FuncDef.flags. Note that the _LENGTH and _TYPEOF
+** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG. There
+** are assert() statements in the code to verify this.
+*/
+#define SQLITE_FUNC_ENCMASK 0x003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
+#define SQLITE_FUNC_LIKE 0x004 /* Candidate for the LIKE optimization */
+#define SQLITE_FUNC_CASE 0x008 /* Case-sensitive LIKE-type function */
+#define SQLITE_FUNC_EPHEM 0x010 /* Ephemeral. Delete with VDBE */
+#define SQLITE_FUNC_NEEDCOLL 0x020 /* sqlite3GetFuncCollSeq() might be called */
+#define SQLITE_FUNC_LENGTH 0x040 /* Built-in length() function */
+#define SQLITE_FUNC_TYPEOF 0x080 /* Built-in typeof() function */
+#define SQLITE_FUNC_COUNT 0x100 /* Built-in count(*) aggregate */
+#define SQLITE_FUNC_COALESCE 0x200 /* Built-in coalesce() or ifnull() */
+#define SQLITE_FUNC_UNLIKELY 0x400 /* Built-in unlikely() function */
+#define SQLITE_FUNC_CONSTANT 0x800 /* Constant inputs give a constant output */
+
+/*
+** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
+** used to create the initializers for the FuncDef structures.
+**
+** FUNCTION(zName, nArg, iArg, bNC, xFunc)
+** Used to create a scalar function definition of a function zName
+** implemented by C function xFunc that accepts nArg arguments. The
+** value passed as iArg is cast to a (void*) and made available
+** as the user-data (sqlite3_user_data()) for the function. If
+** argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
+**
+** VFUNCTION(zName, nArg, iArg, bNC, xFunc)
+** Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
+**
+** AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
+** Used to create an aggregate function definition implemented by
+** the C functions xStep and xFinal. The first four parameters
+** are interpreted in the same way as the first 4 parameters to
+** FUNCTION().
+**
+** LIKEFUNC(zName, nArg, pArg, flags)
+** Used to create a scalar function definition of a function zName
+** that accepts nArg arguments and is implemented by a call to C
+** function likeFunc. Argument pArg is cast to a (void *) and made
+** available as the function user-data (sqlite3_user_data()). The
+** FuncDef.flags variable is set to the value passed as the flags
+** parameter.
+*/
+#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
+ {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
+ SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
+#define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
+ {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
+ SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
+#define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
+ {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
+ SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName, 0, 0}
+#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
+ {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
+ pArg, 0, xFunc, 0, 0, #zName, 0, 0}
+#define LIKEFUNC(zName, nArg, arg, flags) \
+ {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
+ (void *)arg, 0, likeFunc, 0, 0, #zName, 0, 0}
+#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
+ {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
+ SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal,#zName,0,0}
+
+/*
+** All current savepoints are stored in a linked list starting at
+** sqlite3.pSavepoint. The first element in the list is the most recently
+** opened savepoint. Savepoints are added to the list by the vdbe
+** OP_Savepoint instruction.
+*/
+struct Savepoint {
+ char *zName; /* Savepoint name (nul-terminated) */
+ i64 nDeferredCons; /* Number of deferred fk violations */
+ i64 nDeferredImmCons; /* Number of deferred imm fk. */
+ Savepoint *pNext; /* Parent savepoint (if any) */
+};
+
+/*
+** The following are used as the second parameter to sqlite3Savepoint(),
+** and as the P1 argument to the OP_Savepoint instruction.
+*/
+#define SAVEPOINT_BEGIN 0
+#define SAVEPOINT_RELEASE 1
+#define SAVEPOINT_ROLLBACK 2
+
+
+/*
+** Each SQLite module (virtual table definition) is defined by an
+** instance of the following structure, stored in the sqlite3.aModule
+** hash table.
+*/
+struct Module {
+ const sqlite3_module *pModule; /* Callback pointers */
+ const char *zName; /* Name passed to create_module() */
+ void *pAux; /* pAux passed to create_module() */
+ void (*xDestroy)(void *); /* Module destructor function */
+};
+
+/*
+** information about each column of an SQL table is held in an instance
+** of this structure.
+*/
+struct Column {
+ char *zName; /* Name of this column */
+ Expr *pDflt; /* Default value of this column */
+ char *zDflt; /* Original text of the default value */
+ char *zType; /* Data type for this column */
+ char *zColl; /* Collating sequence. If NULL, use the default */
+ u8 notNull; /* An OE_ code for handling a NOT NULL constraint */
+ char affinity; /* One of the SQLITE_AFF_... values */
+ u8 szEst; /* Estimated size of this column. INT==1 */
+ u8 colFlags; /* Boolean properties. See COLFLAG_ defines below */
+};
+
+/* Allowed values for Column.colFlags:
+*/
+#define COLFLAG_PRIMKEY 0x0001 /* Column is part of the primary key */
+#define COLFLAG_HIDDEN 0x0002 /* A hidden column in a virtual table */
+
+/*
+** A "Collating Sequence" is defined by an instance of the following
+** structure. Conceptually, a collating sequence consists of a name and
+** a comparison routine that defines the order of that sequence.
+**
+** If CollSeq.xCmp is NULL, it means that the
+** collating sequence is undefined. Indices built on an undefined
+** collating sequence may not be read or written.
+*/
+struct CollSeq {
+ char *zName; /* Name of the collating sequence, UTF-8 encoded */
+ u8 enc; /* Text encoding handled by xCmp() */
+ void *pUser; /* First argument to xCmp() */
+ int (*xCmp)(void*,int, const void*, int, const void*);
+ void (*xDel)(void*); /* Destructor for pUser */
+};
+
+/*
+** A sort order can be either ASC or DESC.
+*/
+#define SQLITE_SO_ASC 0 /* Sort in ascending order */
+#define SQLITE_SO_DESC 1 /* Sort in ascending order */
+
+/*
+** Column affinity types.
+**
+** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
+** 't' for SQLITE_AFF_TEXT. But we can save a little space and improve
+** the speed a little by numbering the values consecutively.
+**
+** But rather than start with 0 or 1, we begin with 'a'. That way,
+** when multiple affinity types are concatenated into a string and
+** used as the P4 operand, they will be more readable.
+**
+** Note also that the numeric types are grouped together so that testing
+** for a numeric type is a single comparison.
+*/
+#define SQLITE_AFF_TEXT 'a'
+#define SQLITE_AFF_NONE 'b'
+#define SQLITE_AFF_NUMERIC 'c'
+#define SQLITE_AFF_INTEGER 'd'
+#define SQLITE_AFF_REAL 'e'
+
+#define sqlite3IsNumericAffinity(X) ((X)>=SQLITE_AFF_NUMERIC)
+
+/*
+** The SQLITE_AFF_MASK values masks off the significant bits of an
+** affinity value.
+*/
+#define SQLITE_AFF_MASK 0x67
+
+/*
+** Additional bit values that can be ORed with an affinity without
+** changing the affinity.
+**
+** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
+** It causes an assert() to fire if either operand to a comparison
+** operator is NULL. It is added to certain comparison operators to
+** prove that the operands are always NOT NULL.
+*/
+#define SQLITE_JUMPIFNULL 0x08 /* jumps if either operand is NULL */
+#define SQLITE_STOREP2 0x10 /* Store result in reg[P2] rather than jump */
+#define SQLITE_NULLEQ 0x80 /* NULL=NULL */
+#define SQLITE_NOTNULL 0x88 /* Assert that operands are never NULL */
+
+/*
+** An object of this type is created for each virtual table present in
+** the database schema.
+**
+** If the database schema is shared, then there is one instance of this
+** structure for each database connection (sqlite3*) that uses the shared
+** schema. This is because each database connection requires its own unique
+** instance of the sqlite3_vtab* handle used to access the virtual table
+** implementation. sqlite3_vtab* handles can not be shared between
+** database connections, even when the rest of the in-memory database
+** schema is shared, as the implementation often stores the database
+** connection handle passed to it via the xConnect() or xCreate() method
+** during initialization internally. This database connection handle may
+** then be used by the virtual table implementation to access real tables
+** within the database. So that they appear as part of the callers
+** transaction, these accesses need to be made via the same database
+** connection as that used to execute SQL operations on the virtual table.
+**
+** All VTable objects that correspond to a single table in a shared
+** database schema are initially stored in a linked-list pointed to by
+** the Table.pVTable member variable of the corresponding Table object.
+** When an sqlite3_prepare() operation is required to access the virtual
+** table, it searches the list for the VTable that corresponds to the
+** database connection doing the preparing so as to use the correct
+** sqlite3_vtab* handle in the compiled query.
+**
+** When an in-memory Table object is deleted (for example when the
+** schema is being reloaded for some reason), the VTable objects are not
+** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
+** immediately. Instead, they are moved from the Table.pVTable list to
+** another linked list headed by the sqlite3.pDisconnect member of the
+** corresponding sqlite3 structure. They are then deleted/xDisconnected
+** next time a statement is prepared using said sqlite3*. This is done
+** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
+** Refer to comments above function sqlite3VtabUnlockList() for an
+** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
+** list without holding the corresponding sqlite3.mutex mutex.
+**
+** The memory for objects of this type is always allocated by
+** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
+** the first argument.
+*/
+struct VTable {
+ sqlite3 *db; /* Database connection associated with this table */
+ Module *pMod; /* Pointer to module implementation */
+ sqlite3_vtab *pVtab; /* Pointer to vtab instance */
+ int nRef; /* Number of pointers to this structure */
+ u8 bConstraint; /* True if constraints are supported */
+ int iSavepoint; /* Depth of the SAVEPOINT stack */
+ VTable *pNext; /* Next in linked list (see above) */
+};
+
+/*
+** Each SQL table is represented in memory by an instance of the
+** following structure.
+**
+** Table.zName is the name of the table. The case of the original
+** CREATE TABLE statement is stored, but case is not significant for
+** comparisons.
+**
+** Table.nCol is the number of columns in this table. Table.aCol is a
+** pointer to an array of Column structures, one for each column.
+**
+** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
+** the column that is that key. Otherwise Table.iPKey is negative. Note
+** that the datatype of the PRIMARY KEY must be INTEGER for this field to
+** be set. An INTEGER PRIMARY KEY is used as the rowid for each row of
+** the table. If a table has no INTEGER PRIMARY KEY, then a random rowid
+** is generated for each row of the table. TF_HasPrimaryKey is set if
+** the table has any PRIMARY KEY, INTEGER or otherwise.
+**
+** Table.tnum is the page number for the root BTree page of the table in the
+** database file. If Table.iDb is the index of the database table backend
+** in sqlite.aDb[]. 0 is for the main database and 1 is for the file that
+** holds temporary tables and indices. If TF_Ephemeral is set
+** then the table is stored in a file that is automatically deleted
+** when the VDBE cursor to the table is closed. In this case Table.tnum
+** refers VDBE cursor number that holds the table open, not to the root
+** page number. Transient tables are used to hold the results of a
+** sub-query that appears instead of a real table name in the FROM clause
+** of a SELECT statement.
+*/
+struct Table {
+ char *zName; /* Name of the table or view */
+ Column *aCol; /* Information about each column */
+ Index *pIndex; /* List of SQL indexes on this table. */
+ Select *pSelect; /* NULL for tables. Points to definition if a view. */
+ FKey *pFKey; /* Linked list of all foreign keys in this table */
+ char *zColAff; /* String defining the affinity of each column */
+#ifndef SQLITE_OMIT_CHECK
+ ExprList *pCheck; /* All CHECK constraints */
+#endif
+ LogEst nRowLogEst; /* Estimated rows in table - from sqlite_stat1 table */
+ int tnum; /* Root BTree node for this table (see note above) */
+ i16 iPKey; /* If not negative, use aCol[iPKey] as the primary key */
+ i16 nCol; /* Number of columns in this table */
+ u16 nRef; /* Number of pointers to this Table */
+ LogEst szTabRow; /* Estimated size of each table row in bytes */
+ u8 tabFlags; /* Mask of TF_* values */
+ u8 keyConf; /* What to do in case of uniqueness conflict on iPKey */
+#ifndef SQLITE_OMIT_ALTERTABLE
+ int addColOffset; /* Offset in CREATE TABLE stmt to add a new column */
+#endif
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ int nModuleArg; /* Number of arguments to the module */
+ char **azModuleArg; /* Text of all module args. [0] is module name */
+ VTable *pVTable; /* List of VTable objects. */
+#endif
+ Trigger *pTrigger; /* List of triggers stored in pSchema */
+ Schema *pSchema; /* Schema that contains this table */
+ Table *pNextZombie; /* Next on the Parse.pZombieTab list */
+};
+
+/*
+** Allowed values for Table.tabFlags.
+*/
+#define TF_Readonly 0x01 /* Read-only system table */
+#define TF_Ephemeral 0x02 /* An ephemeral table */
+#define TF_HasPrimaryKey 0x04 /* Table has a primary key */
+#define TF_Autoincrement 0x08 /* Integer primary key is autoincrement */
+#define TF_Virtual 0x10 /* Is a virtual table */
+#define TF_WithoutRowid 0x20 /* No rowid used. PRIMARY KEY is the key */
+
+
+/*
+** Test to see whether or not a table is a virtual table. This is
+** done as a macro so that it will be optimized out when virtual
+** table support is omitted from the build.
+*/
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+# define IsVirtual(X) (((X)->tabFlags & TF_Virtual)!=0)
+# define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
+#else
+# define IsVirtual(X) 0
+# define IsHiddenColumn(X) 0
+#endif
+
+/* Does the table have a rowid */
+#define HasRowid(X) (((X)->tabFlags & TF_WithoutRowid)==0)
+
+/*
+** Each foreign key constraint is an instance of the following structure.
+**
+** A foreign key is associated with two tables. The "from" table is
+** the table that contains the REFERENCES clause that creates the foreign
+** key. The "to" table is the table that is named in the REFERENCES clause.
+** Consider this example:
+**
+** CREATE TABLE ex1(
+** a INTEGER PRIMARY KEY,
+** b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
+** );
+**
+** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
+** Equivalent names:
+**
+** from-table == child-table
+** to-table == parent-table
+**
+** Each REFERENCES clause generates an instance of the following structure
+** which is attached to the from-table. The to-table need not exist when
+** the from-table is created. The existence of the to-table is not checked.
+**
+** The list of all parents for child Table X is held at X.pFKey.
+**
+** A list of all children for a table named Z (which might not even exist)
+** is held in Schema.fkeyHash with a hash key of Z.
+*/
+struct FKey {
+ Table *pFrom; /* Table containing the REFERENCES clause (aka: Child) */
+ FKey *pNextFrom; /* Next FKey with the same in pFrom. Next parent of pFrom */
+ char *zTo; /* Name of table that the key points to (aka: Parent) */
+ FKey *pNextTo; /* Next with the same zTo. Next child of zTo. */
+ FKey *pPrevTo; /* Previous with the same zTo */
+ int nCol; /* Number of columns in this key */
+ /* EV: R-30323-21917 */
+ u8 isDeferred; /* True if constraint checking is deferred till COMMIT */
+ u8 aAction[2]; /* ON DELETE and ON UPDATE actions, respectively */
+ Trigger *apTrigger[2];/* Triggers for aAction[] actions */
+ struct sColMap { /* Mapping of columns in pFrom to columns in zTo */
+ int iFrom; /* Index of column in pFrom */
+ char *zCol; /* Name of column in zTo. If NULL use PRIMARY KEY */
+ } aCol[1]; /* One entry for each of nCol columns */
+};
+
+/*
+** SQLite supports many different ways to resolve a constraint
+** error. ROLLBACK processing means that a constraint violation
+** causes the operation in process to fail and for the current transaction
+** to be rolled back. ABORT processing means the operation in process
+** fails and any prior changes from that one operation are backed out,
+** but the transaction is not rolled back. FAIL processing means that
+** the operation in progress stops and returns an error code. But prior
+** changes due to the same operation are not backed out and no rollback
+** occurs. IGNORE means that the particular row that caused the constraint
+** error is not inserted or updated. Processing continues and no error
+** is returned. REPLACE means that preexisting database rows that caused
+** a UNIQUE constraint violation are removed so that the new insert or
+** update can proceed. Processing continues and no error is reported.
+**
+** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
+** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
+** same as ROLLBACK for DEFERRED keys. SETNULL means that the foreign
+** key is set to NULL. CASCADE means that a DELETE or UPDATE of the
+** referenced table row is propagated into the row that holds the
+** foreign key.
+**
+** The following symbolic values are used to record which type
+** of action to take.
+*/
+#define OE_None 0 /* There is no constraint to check */
+#define OE_Rollback 1 /* Fail the operation and rollback the transaction */
+#define OE_Abort 2 /* Back out changes but do no rollback transaction */
+#define OE_Fail 3 /* Stop the operation but leave all prior changes */
+#define OE_Ignore 4 /* Ignore the error. Do not do the INSERT or UPDATE */
+#define OE_Replace 5 /* Delete existing record, then do INSERT or UPDATE */
+
+#define OE_Restrict 6 /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
+#define OE_SetNull 7 /* Set the foreign key value to NULL */
+#define OE_SetDflt 8 /* Set the foreign key value to its default */
+#define OE_Cascade 9 /* Cascade the changes */
+
+#define OE_Default 10 /* Do whatever the default action is */
+
+
+/*
+** An instance of the following structure is passed as the first
+** argument to sqlite3VdbeKeyCompare and is used to control the
+** comparison of the two index keys.
+**
+** Note that aSortOrder[] and aColl[] have nField+1 slots. There
+** are nField slots for the columns of an index then one extra slot
+** for the rowid at the end.
+*/
+struct KeyInfo {
+ u32 nRef; /* Number of references to this KeyInfo object */
+ u8 enc; /* Text encoding - one of the SQLITE_UTF* values */
+ u16 nField; /* Number of key columns in the index */
+ u16 nXField; /* Number of columns beyond the key columns */
+ sqlite3 *db; /* The database connection */
+ u8 *aSortOrder; /* Sort order for each column. */
+ CollSeq *aColl[1]; /* Collating sequence for each term of the key */
+};
+
+/*
+** An instance of the following structure holds information about a
+** single index record that has already been parsed out into individual
+** values.
+**
+** A record is an object that contains one or more fields of data.
+** Records are used to store the content of a table row and to store
+** the key of an index. A blob encoding of a record is created by
+** the OP_MakeRecord opcode of the VDBE and is disassembled by the
+** OP_Column opcode.
+**
+** This structure holds a record that has already been disassembled
+** into its constituent fields.
+**
+** The r1 and r2 member variables are only used by the optimized comparison
+** functions vdbeRecordCompareInt() and vdbeRecordCompareString().
+*/
+struct UnpackedRecord {
+ KeyInfo *pKeyInfo; /* Collation and sort-order information */
+ u16 nField; /* Number of entries in apMem[] */
+ i8 default_rc; /* Comparison result if keys are equal */
+ u8 isCorrupt; /* Corruption detected by xRecordCompare() */
+ Mem *aMem; /* Values */
+ int r1; /* Value to return if (lhs > rhs) */
+ int r2; /* Value to return if (rhs < lhs) */
+};
+
+
+/*
+** Each SQL index is represented in memory by an
+** instance of the following structure.
+**
+** The columns of the table that are to be indexed are described
+** by the aiColumn[] field of this structure. For example, suppose
+** we have the following table and index:
+**
+** CREATE TABLE Ex1(c1 int, c2 int, c3 text);
+** CREATE INDEX Ex2 ON Ex1(c3,c1);
+**
+** In the Table structure describing Ex1, nCol==3 because there are
+** three columns in the table. In the Index structure describing
+** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
+** The value of aiColumn is {2, 0}. aiColumn[0]==2 because the
+** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
+** The second column to be indexed (c1) has an index of 0 in
+** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
+**
+** The Index.onError field determines whether or not the indexed columns
+** must be unique and what to do if they are not. When Index.onError=OE_None,
+** it means this is not a unique index. Otherwise it is a unique index
+** and the value of Index.onError indicate the which conflict resolution
+** algorithm to employ whenever an attempt is made to insert a non-unique
+** element.
+*/
+struct Index {
+ char *zName; /* Name of this index */
+ i16 *aiColumn; /* Which columns are used by this index. 1st is 0 */
+ LogEst *aiRowLogEst; /* From ANALYZE: Est. rows selected by each column */
+ Table *pTable; /* The SQL table being indexed */
+ char *zColAff; /* String defining the affinity of each column */
+ Index *pNext; /* The next index associated with the same table */
+ Schema *pSchema; /* Schema containing this index */
+ u8 *aSortOrder; /* for each column: True==DESC, False==ASC */
+ char **azColl; /* Array of collation sequence names for index */
+ Expr *pPartIdxWhere; /* WHERE clause for partial indices */
+ KeyInfo *pKeyInfo; /* A KeyInfo object suitable for this index */
+ int tnum; /* DB Page containing root of this index */
+ LogEst szIdxRow; /* Estimated average row size in bytes */
+ u16 nKeyCol; /* Number of columns forming the key */
+ u16 nColumn; /* Number of columns stored in the index */
+ u8 onError; /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
+ unsigned idxType:2; /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
+ unsigned bUnordered:1; /* Use this index for == or IN queries only */
+ unsigned uniqNotNull:1; /* True if UNIQUE and NOT NULL for all columns */
+ unsigned isResized:1; /* True if resizeIndexObject() has been called */
+ unsigned isCovering:1; /* True if this is a covering index */
+#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
+ int nSample; /* Number of elements in aSample[] */
+ int nSampleCol; /* Size of IndexSample.anEq[] and so on */
+ tRowcnt *aAvgEq; /* Average nEq values for keys not in aSample */
+ IndexSample *aSample; /* Samples of the left-most key */
+#endif
+};
+
+/*
+** Allowed values for Index.idxType
+*/
+#define SQLITE_IDXTYPE_APPDEF 0 /* Created using CREATE INDEX */
+#define SQLITE_IDXTYPE_UNIQUE 1 /* Implements a UNIQUE constraint */
+#define SQLITE_IDXTYPE_PRIMARYKEY 2 /* Is the PRIMARY KEY for the table */
+
+/* Return true if index X is a PRIMARY KEY index */
+#define IsPrimaryKeyIndex(X) ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)
+
+/*
+** Each sample stored in the sqlite_stat3 table is represented in memory
+** using a structure of this type. See documentation at the top of the
+** analyze.c source file for additional information.
+*/
+struct IndexSample {
+ void *p; /* Pointer to sampled record */
+ int n; /* Size of record in bytes */
+ tRowcnt *anEq; /* Est. number of rows where the key equals this sample */
+ tRowcnt *anLt; /* Est. number of rows where key is less than this sample */
+ tRowcnt *anDLt; /* Est. number of distinct keys less than this sample */
+};
+
+/*
+** Each token coming out of the lexer is an instance of
+** this structure. Tokens are also used as part of an expression.
+**
+** Note if Token.z==0 then Token.dyn and Token.n are undefined and
+** may contain random values. Do not make any assumptions about Token.dyn
+** and Token.n when Token.z==0.
+*/
+struct Token {
+ const char *z; /* Text of the token. Not NULL-terminated! */
+ unsigned int n; /* Number of characters in this token */
+};
+
+/*
+** An instance of this structure contains information needed to generate
+** code for a SELECT that contains aggregate functions.
+**
+** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
+** pointer to this structure. The Expr.iColumn field is the index in
+** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
+** code for that node.
+**
+** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
+** original Select structure that describes the SELECT statement. These
+** fields do not need to be freed when deallocating the AggInfo structure.
+*/
+struct AggInfo {
+ u8 directMode; /* Direct rendering mode means take data directly
+ ** from source tables rather than from accumulators */
+ u8 useSortingIdx; /* In direct mode, reference the sorting index rather
+ ** than the source table */
+ int sortingIdx; /* Cursor number of the sorting index */
+ int sortingIdxPTab; /* Cursor number of pseudo-table */
+ int nSortingColumn; /* Number of columns in the sorting index */
+ int mnReg, mxReg; /* Range of registers allocated for aCol and aFunc */
+ ExprList *pGroupBy; /* The group by clause */
+ struct AggInfo_col { /* For each column used in source tables */
+ Table *pTab; /* Source table */
+ int iTable; /* Cursor number of the source table */
+ int iColumn; /* Column number within the source table */
+ int iSorterColumn; /* Column number in the sorting index */
+ int iMem; /* Memory location that acts as accumulator */
+ Expr *pExpr; /* The original expression */
+ } *aCol;
+ int nColumn; /* Number of used entries in aCol[] */
+ int nAccumulator; /* Number of columns that show through to the output.
+ ** Additional columns are used only as parameters to
+ ** aggregate functions */
+ struct AggInfo_func { /* For each aggregate function */
+ Expr *pExpr; /* Expression encoding the function */
+ FuncDef *pFunc; /* The aggregate function implementation */
+ int iMem; /* Memory location that acts as accumulator */
+ int iDistinct; /* Ephemeral table used to enforce DISTINCT */
+ } *aFunc;
+ int nFunc; /* Number of entries in aFunc[] */
+};
+
+/*
+** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
+** Usually it is 16-bits. But if SQLITE_MAX_VARIABLE_NUMBER is greater
+** than 32767 we have to make it 32-bit. 16-bit is preferred because
+** it uses less memory in the Expr object, which is a big memory user
+** in systems with lots of prepared statements. And few applications
+** need more than about 10 or 20 variables. But some extreme users want
+** to have prepared statements with over 32767 variables, and for them
+** the option is available (at compile-time).
+*/
+#if SQLITE_MAX_VARIABLE_NUMBER<=32767
+typedef i16 ynVar;
+#else
+typedef int ynVar;
+#endif
+
+/*
+** Each node of an expression in the parse tree is an instance
+** of this structure.
+**
+** Expr.op is the opcode. The integer parser token codes are reused
+** as opcodes here. For example, the parser defines TK_GE to be an integer
+** code representing the ">=" operator. This same integer code is reused
+** to represent the greater-than-or-equal-to operator in the expression
+** tree.
+**
+** If the expression is an SQL literal (TK_INTEGER, TK_FLOAT, TK_BLOB,
+** or TK_STRING), then Expr.token contains the text of the SQL literal. If
+** the expression is a variable (TK_VARIABLE), then Expr.token contains the
+** variable name. Finally, if the expression is an SQL function (TK_FUNCTION),
+** then Expr.token contains the name of the function.
+**
+** Expr.pRight and Expr.pLeft are the left and right subexpressions of a
+** binary operator. Either or both may be NULL.
+**
+** Expr.x.pList is a list of arguments if the expression is an SQL function,
+** a CASE expression or an IN expression of the form " IN (, ...)".
+** Expr.x.pSelect is used if the expression is a sub-select or an expression of
+** the form " IN (SELECT ...)". If the EP_xIsSelect bit is set in the
+** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
+** valid.
+**
+** An expression of the form ID or ID.ID refers to a column in a table.
+** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
+** the integer cursor number of a VDBE cursor pointing to that table and
+** Expr.iColumn is the column number for the specific column. If the
+** expression is used as a result in an aggregate SELECT, then the
+** value is also stored in the Expr.iAgg column in the aggregate so that
+** it can be accessed after all aggregates are computed.
+**
+** If the expression is an unbound variable marker (a question mark
+** character '?' in the original SQL) then the Expr.iTable holds the index
+** number for that variable.
+**
+** If the expression is a subquery then Expr.iColumn holds an integer
+** register number containing the result of the subquery. If the
+** subquery gives a constant result, then iTable is -1. If the subquery
+** gives a different answer at different times during statement processing
+** then iTable is the address of a subroutine that computes the subquery.
+**
+** If the Expr is of type OP_Column, and the table it is selecting from
+** is a disk table or the "old.*" pseudo-table, then pTab points to the
+** corresponding table definition.
+**
+** ALLOCATION NOTES:
+**
+** Expr objects can use a lot of memory space in database schema. To
+** help reduce memory requirements, sometimes an Expr object will be
+** truncated. And to reduce the number of memory allocations, sometimes
+** two or more Expr objects will be stored in a single memory allocation,
+** together with Expr.zToken strings.
+**
+** If the EP_Reduced and EP_TokenOnly flags are set when
+** an Expr object is truncated. When EP_Reduced is set, then all
+** the child Expr objects in the Expr.pLeft and Expr.pRight subtrees
+** are contained within the same memory allocation. Note, however, that
+** the subtrees in Expr.x.pList or Expr.x.pSelect are always separately
+** allocated, regardless of whether or not EP_Reduced is set.
+*/
+struct Expr {
+ u8 op; /* Operation performed by this node */
+ char affinity; /* The affinity of the column or 0 if not a column */
+ u32 flags; /* Various flags. EP_* See below */
+ union {
+ char *zToken; /* Token value. Zero terminated and dequoted */
+ int iValue; /* Non-negative integer value if EP_IntValue */
+ } u;
+
+ /* If the EP_TokenOnly flag is set in the Expr.flags mask, then no
+ ** space is allocated for the fields below this point. An attempt to
+ ** access them will result in a segfault or malfunction.
+ *********************************************************************/
+
+ Expr *pLeft; /* Left subnode */
+ Expr *pRight; /* Right subnode */
+ union {
+ ExprList *pList; /* op = IN, EXISTS, SELECT, CASE, FUNCTION, BETWEEN */
+ Select *pSelect; /* EP_xIsSelect and op = IN, EXISTS, SELECT */
+ } x;
+
+ /* If the EP_Reduced flag is set in the Expr.flags mask, then no
+ ** space is allocated for the fields below this point. An attempt to
+ ** access them will result in a segfault or malfunction.
+ *********************************************************************/
+
+#if SQLITE_MAX_EXPR_DEPTH>0
+ int nHeight; /* Height of the tree headed by this node */
+#endif
+ int iTable; /* TK_COLUMN: cursor number of table holding column
+ ** TK_REGISTER: register number
+ ** TK_TRIGGER: 1 -> new, 0 -> old
+ ** EP_Unlikely: 1000 times likelihood */
+ ynVar iColumn; /* TK_COLUMN: column index. -1 for rowid.
+ ** TK_VARIABLE: variable number (always >= 1). */
+ i16 iAgg; /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
+ i16 iRightJoinTable; /* If EP_FromJoin, the right table of the join */
+ u8 op2; /* TK_REGISTER: original value of Expr.op
+ ** TK_COLUMN: the value of p5 for OP_Column
+ ** TK_AGG_FUNCTION: nesting depth */
+ AggInfo *pAggInfo; /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
+ Table *pTab; /* Table for TK_COLUMN expressions. */
+};
+
+/*
+** The following are the meanings of bits in the Expr.flags field.
+*/
+#define EP_FromJoin 0x000001 /* Originated in ON or USING clause of a join */
+#define EP_Agg 0x000002 /* Contains one or more aggregate functions */
+#define EP_Resolved 0x000004 /* IDs have been resolved to COLUMNs */
+#define EP_Error 0x000008 /* Expression contains one or more errors */
+#define EP_Distinct 0x000010 /* Aggregate function with DISTINCT keyword */
+#define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
+#define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
+#define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
+#define EP_Collate 0x000100 /* Tree contains a TK_COLLATE operator */
+#define EP_Generic 0x000200 /* Ignore COLLATE or affinity on this tree */
+#define EP_IntValue 0x000400 /* Integer value contained in u.iValue */
+#define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
+#define EP_Skip 0x001000 /* COLLATE, AS, or UNLIKELY */
+#define EP_Reduced 0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
+#define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
+#define EP_Static 0x008000 /* Held in memory not obtained from malloc() */
+#define EP_MemToken 0x010000 /* Need to sqlite3DbFree() Expr.zToken */
+#define EP_NoReduce 0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
+#define EP_Unlikely 0x040000 /* unlikely() or likelihood() function */
+#define EP_Constant 0x080000 /* Node is a constant */
+
+/*
+** These macros can be used to test, set, or clear bits in the
+** Expr.flags field.
+*/
+#define ExprHasProperty(E,P) (((E)->flags&(P))!=0)
+#define ExprHasAllProperty(E,P) (((E)->flags&(P))==(P))
+#define ExprSetProperty(E,P) (E)->flags|=(P)
+#define ExprClearProperty(E,P) (E)->flags&=~(P)
+
+/* The ExprSetVVAProperty() macro is used for Verification, Validation,
+** and Accreditation only. It works like ExprSetProperty() during VVA
+** processes but is a no-op for delivery.
+*/
+#ifdef SQLITE_DEBUG
+# define ExprSetVVAProperty(E,P) (E)->flags|=(P)
+#else
+# define ExprSetVVAProperty(E,P)
+#endif
+
+/*
+** Macros to determine the number of bytes required by a normal Expr
+** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
+** and an Expr struct with the EP_TokenOnly flag set.
+*/
+#define EXPR_FULLSIZE sizeof(Expr) /* Full size */
+#define EXPR_REDUCEDSIZE offsetof(Expr,iTable) /* Common features */
+#define EXPR_TOKENONLYSIZE offsetof(Expr,pLeft) /* Fewer features */
+
+/*
+** Flags passed to the sqlite3ExprDup() function. See the header comment
+** above sqlite3ExprDup() for details.
+*/
+#define EXPRDUP_REDUCE 0x0001 /* Used reduced-size Expr nodes */
+
+/*
+** A list of expressions. Each expression may optionally have a
+** name. An expr/name combination can be used in several ways, such
+** as the list of "expr AS ID" fields following a "SELECT" or in the
+** list of "ID = expr" items in an UPDATE. A list of expressions can
+** also be used as the argument to a function, in which case the a.zName
+** field is not used.
+**
+** By default the Expr.zSpan field holds a human-readable description of
+** the expression that is used in the generation of error messages and
+** column labels. In this case, Expr.zSpan is typically the text of a
+** column expression as it exists in a SELECT statement. However, if
+** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
+** of the result column in the form: DATABASE.TABLE.COLUMN. This later
+** form is used for name resolution with nested FROM clauses.
+*/
+struct ExprList {
+ int nExpr; /* Number of expressions on the list */
+ struct ExprList_item { /* For each expression in the list */
+ Expr *pExpr; /* The list of expressions */
+ char *zName; /* Token associated with this expression */
+ char *zSpan; /* Original text of the expression */
+ u8 sortOrder; /* 1 for DESC or 0 for ASC */
+ unsigned done :1; /* A flag to indicate when processing is finished */
+ unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
+ unsigned reusable :1; /* Constant expression is reusable */
+ union {
+ struct {
+ u16 iOrderByCol; /* For ORDER BY, column number in result set */
+ u16 iAlias; /* Index into Parse.aAlias[] for zName */
+ } x;
+ int iConstExprReg; /* Register in which Expr value is cached */
+ } u;
+ } *a; /* Alloc a power of two greater or equal to nExpr */
+};
+
+/*
+** An instance of this structure is used by the parser to record both
+** the parse tree for an expression and the span of input text for an
+** expression.
+*/
+struct ExprSpan {
+ Expr *pExpr; /* The expression parse tree */
+ const char *zStart; /* First character of input text */
+ const char *zEnd; /* One character past the end of input text */
+};
+
+/*
+** An instance of this structure can hold a simple list of identifiers,
+** such as the list "a,b,c" in the following statements:
+**
+** INSERT INTO t(a,b,c) VALUES ...;
+** CREATE INDEX idx ON t(a,b,c);
+** CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
+**
+** The IdList.a.idx field is used when the IdList represents the list of
+** column names after a table name in an INSERT statement. In the statement
+**
+** INSERT INTO t(a,b,c) ...
+**
+** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
+*/
+struct IdList {
+ struct IdList_item {
+ char *zName; /* Name of the identifier */
+ int idx; /* Index in some Table.aCol[] of a column named zName */
+ } *a;
+ int nId; /* Number of identifiers on the list */
+};
+
+/*
+** The bitmask datatype defined below is used for various optimizations.
+**
+** Changing this from a 64-bit to a 32-bit type limits the number of
+** tables in a join to 32 instead of 64. But it also reduces the size
+** of the library by 738 bytes on ix86.
+*/
+typedef u64 Bitmask;
+
+/*
+** The number of bits in a Bitmask. "BMS" means "BitMask Size".
+*/
+#define BMS ((int)(sizeof(Bitmask)*8))
+
+/*
+** A bit in a Bitmask
+*/
+#define MASKBIT(n) (((Bitmask)1)<<(n))
+#define MASKBIT32(n) (((unsigned int)1)<<(n))
+
+/*
+** The following structure describes the FROM clause of a SELECT statement.
+** Each table or subquery in the FROM clause is a separate element of
+** the SrcList.a[] array.
+**
+** With the addition of multiple database support, the following structure
+** can also be used to describe a particular table such as the table that
+** is modified by an INSERT, DELETE, or UPDATE statement. In standard SQL,
+** such a table must be a simple name: ID. But in SQLite, the table can
+** now be identified by a database name, a dot, then the table name: ID.ID.
+**
+** The jointype starts out showing the join type between the current table
+** and the next table on the list. The parser builds the list this way.
+** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
+** jointype expresses the join between the table and the previous table.
+**
+** In the colUsed field, the high-order bit (bit 63) is set if the table
+** contains more than 63 columns and the 64-th or later column is used.
+*/
+struct SrcList {
+ int nSrc; /* Number of tables or subqueries in the FROM clause */
+ u32 nAlloc; /* Number of entries allocated in a[] below */
+ struct SrcList_item {
+ Schema *pSchema; /* Schema to which this item is fixed */
+ char *zDatabase; /* Name of database holding this table */
+ char *zName; /* Name of the table */
+ char *zAlias; /* The "B" part of a "A AS B" phrase. zName is the "A" */
+ Table *pTab; /* An SQL table corresponding to zName */
+ Select *pSelect; /* A SELECT statement used in place of a table name */
+ int addrFillSub; /* Address of subroutine to manifest a subquery */
+ int regReturn; /* Register holding return address of addrFillSub */
+ int regResult; /* Registers holding results of a co-routine */
+ u8 jointype; /* Type of join between this able and the previous */
+ unsigned notIndexed :1; /* True if there is a NOT INDEXED clause */
+ unsigned isCorrelated :1; /* True if sub-query is correlated */
+ unsigned viaCoroutine :1; /* Implemented as a co-routine */
+ unsigned isRecursive :1; /* True for recursive reference in WITH */
+#ifndef SQLITE_OMIT_EXPLAIN
+ u8 iSelectId; /* If pSelect!=0, the id of the sub-select in EQP */
+#endif
+ int iCursor; /* The VDBE cursor number used to access this table */
+ Expr *pOn; /* The ON clause of a join */
+ IdList *pUsing; /* The USING clause of a join */
+ Bitmask colUsed; /* Bit N (1<" clause */
+ Index *pIndex; /* Index structure corresponding to zIndex, if any */
+ } a[1]; /* One entry for each identifier on the list */
+};
+
+/*
+** Permitted values of the SrcList.a.jointype field
+*/
+#define JT_INNER 0x0001 /* Any kind of inner or cross join */
+#define JT_CROSS 0x0002 /* Explicit use of the CROSS keyword */
+#define JT_NATURAL 0x0004 /* True for a "natural" join */
+#define JT_LEFT 0x0008 /* Left outer join */
+#define JT_RIGHT 0x0010 /* Right outer join */
+#define JT_OUTER 0x0020 /* The "OUTER" keyword is present */
+#define JT_ERROR 0x0040 /* unknown or unsupported join type */
+
+
+/*
+** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
+** and the WhereInfo.wctrlFlags member.
+*/
+#define WHERE_ORDERBY_NORMAL 0x0000 /* No-op */
+#define WHERE_ORDERBY_MIN 0x0001 /* ORDER BY processing for min() func */
+#define WHERE_ORDERBY_MAX 0x0002 /* ORDER BY processing for max() func */
+#define WHERE_ONEPASS_DESIRED 0x0004 /* Want to do one-pass UPDATE/DELETE */
+#define WHERE_DUPLICATES_OK 0x0008 /* Ok to return a row more than once */
+#define WHERE_OMIT_OPEN_CLOSE 0x0010 /* Table cursors are already open */
+#define WHERE_FORCE_TABLE 0x0020 /* Do not use an index-only search */
+#define WHERE_ONETABLE_ONLY 0x0040 /* Only code the 1st table in pTabList */
+#define WHERE_AND_ONLY 0x0080 /* Don't use indices for OR terms */
+#define WHERE_GROUPBY 0x0100 /* pOrderBy is really a GROUP BY */
+#define WHERE_DISTINCTBY 0x0200 /* pOrderby is really a DISTINCT clause */
+#define WHERE_WANT_DISTINCT 0x0400 /* All output needs to be distinct */
+#define WHERE_SORTBYGROUP 0x0800 /* Support sqlite3WhereIsSorted() */
+
+/* Allowed return values from sqlite3WhereIsDistinct()
+*/
+#define WHERE_DISTINCT_NOOP 0 /* DISTINCT keyword not used */
+#define WHERE_DISTINCT_UNIQUE 1 /* No duplicates */
+#define WHERE_DISTINCT_ORDERED 2 /* All duplicates are adjacent */
+#define WHERE_DISTINCT_UNORDERED 3 /* Duplicates are scattered */
+
+/*
+** A NameContext defines a context in which to resolve table and column
+** names. The context consists of a list of tables (the pSrcList) field and
+** a list of named expression (pEList). The named expression list may
+** be NULL. The pSrc corresponds to the FROM clause of a SELECT or
+** to the table being operated on by INSERT, UPDATE, or DELETE. The
+** pEList corresponds to the result set of a SELECT and is NULL for
+** other statements.
+**
+** NameContexts can be nested. When resolving names, the inner-most
+** context is searched first. If no match is found, the next outer
+** context is checked. If there is still no match, the next context
+** is checked. This process continues until either a match is found
+** or all contexts are check. When a match is found, the nRef member of
+** the context containing the match is incremented.
+**
+** Each subquery gets a new NameContext. The pNext field points to the
+** NameContext in the parent query. Thus the process of scanning the
+** NameContext list corresponds to searching through successively outer
+** subqueries looking for a match.
+*/
+struct NameContext {
+ Parse *pParse; /* The parser */
+ SrcList *pSrcList; /* One or more tables used to resolve names */
+ ExprList *pEList; /* Optional list of result-set columns */
+ AggInfo *pAggInfo; /* Information about aggregates at this level */
+ NameContext *pNext; /* Next outer name context. NULL for outermost */
+ int nRef; /* Number of names resolved by this context */
+ int nErr; /* Number of errors encountered while resolving names */
+ u8 ncFlags; /* Zero or more NC_* flags defined below */
+};
+
+/*
+** Allowed values for the NameContext, ncFlags field.
+*/
+#define NC_AllowAgg 0x01 /* Aggregate functions are allowed here */
+#define NC_HasAgg 0x02 /* One or more aggregate functions seen */
+#define NC_IsCheck 0x04 /* True if resolving names in a CHECK constraint */
+#define NC_InAggFunc 0x08 /* True if analyzing arguments to an agg func */
+#define NC_PartIdx 0x10 /* True if resolving a partial index WHERE */
+
+/*
+** An instance of the following structure contains all information
+** needed to generate code for a single SELECT statement.
+**
+** nLimit is set to -1 if there is no LIMIT clause. nOffset is set to 0.
+** If there is a LIMIT clause, the parser sets nLimit to the value of the
+** limit and nOffset to the value of the offset (or 0 if there is not
+** offset). But later on, nLimit and nOffset become the memory locations
+** in the VDBE that record the limit and offset counters.
+**
+** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
+** These addresses must be stored so that we can go back and fill in
+** the P4_KEYINFO and P2 parameters later. Neither the KeyInfo nor
+** the number of columns in P2 can be computed at the same time
+** as the OP_OpenEphm instruction is coded because not
+** enough information about the compound query is known at that point.
+** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
+** for the result set. The KeyInfo for addrOpenEphm[2] contains collating
+** sequences for the ORDER BY clause.
+*/
+struct Select {
+ ExprList *pEList; /* The fields of the result */
+ u8 op; /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
+ u16 selFlags; /* Various SF_* values */
+ int iLimit, iOffset; /* Memory registers holding LIMIT & OFFSET counters */
+ int addrOpenEphm[2]; /* OP_OpenEphem opcodes related to this select */
+ u64 nSelectRow; /* Estimated number of result rows */
+ SrcList *pSrc; /* The FROM clause */
+ Expr *pWhere; /* The WHERE clause */
+ ExprList *pGroupBy; /* The GROUP BY clause */
+ Expr *pHaving; /* The HAVING clause */
+ ExprList *pOrderBy; /* The ORDER BY clause */
+ Select *pPrior; /* Prior select in a compound select statement */
+ Select *pNext; /* Next select to the left in a compound */
+ Expr *pLimit; /* LIMIT expression. NULL means not used. */
+ Expr *pOffset; /* OFFSET expression. NULL means not used. */
+ With *pWith; /* WITH clause attached to this select. Or NULL. */
+};
+
+/*
+** Allowed values for Select.selFlags. The "SF" prefix stands for
+** "Select Flag".
+*/
+#define SF_Distinct 0x0001 /* Output should be DISTINCT */
+#define SF_Resolved 0x0002 /* Identifiers have been resolved */
+#define SF_Aggregate 0x0004 /* Contains aggregate functions */
+#define SF_UsesEphemeral 0x0008 /* Uses the OpenEphemeral opcode */
+#define SF_Expanded 0x0010 /* sqlite3SelectExpand() called on this */
+#define SF_HasTypeInfo 0x0020 /* FROM subqueries have Table metadata */
+ /* 0x0040 NOT USED */
+#define SF_Values 0x0080 /* Synthesized from VALUES clause */
+ /* 0x0100 NOT USED */
+#define SF_NestedFrom 0x0200 /* Part of a parenthesized FROM clause */
+#define SF_MaybeConvert 0x0400 /* Need convertCompoundSelectToSubquery() */
+#define SF_Recursive 0x0800 /* The recursive part of a recursive CTE */
+#define SF_Compound 0x1000 /* Part of a compound query */
+
+
+/*
+** The results of a SELECT can be distributed in several ways, as defined
+** by one of the following macros. The "SRT" prefix means "SELECT Result
+** Type".
+**
+** SRT_Union Store results as a key in a temporary index
+** identified by pDest->iSDParm.
+**
+** SRT_Except Remove results from the temporary index pDest->iSDParm.
+**
+** SRT_Exists Store a 1 in memory cell pDest->iSDParm if the result
+** set is not empty.
+**
+** SRT_Discard Throw the results away. This is used by SELECT
+** statements within triggers whose only purpose is
+** the side-effects of functions.
+**
+** All of the above are free to ignore their ORDER BY clause. Those that
+** follow must honor the ORDER BY clause.
+**
+** SRT_Output Generate a row of output (using the OP_ResultRow
+** opcode) for each row in the result set.
+**
+** SRT_Mem Only valid if the result is a single column.
+** Store the first column of the first result row
+** in register pDest->iSDParm then abandon the rest
+** of the query. This destination implies "LIMIT 1".
+**
+** SRT_Set The result must be a single column. Store each
+** row of result as the key in table pDest->iSDParm.
+** Apply the affinity pDest->affSdst before storing
+** results. Used to implement "IN (SELECT ...)".
+**
+** SRT_EphemTab Create an temporary table pDest->iSDParm and store
+** the result there. The cursor is left open after
+** returning. This is like SRT_Table except that
+** this destination uses OP_OpenEphemeral to create
+** the table first.
+**
+** SRT_Coroutine Generate a co-routine that returns a new row of
+** results each time it is invoked. The entry point
+** of the co-routine is stored in register pDest->iSDParm
+** and the result row is stored in pDest->nDest registers
+** starting with pDest->iSdst.
+**
+** SRT_Table Store results in temporary table pDest->iSDParm.
+** SRT_Fifo This is like SRT_EphemTab except that the table
+** is assumed to already be open. SRT_Fifo has
+** the additional property of being able to ignore
+** the ORDER BY clause.
+**
+** SRT_DistFifo Store results in a temporary table pDest->iSDParm.
+** But also use temporary table pDest->iSDParm+1 as
+** a record of all prior results and ignore any duplicate
+** rows. Name means: "Distinct Fifo".
+**
+** SRT_Queue Store results in priority queue pDest->iSDParm (really
+** an index). Append a sequence number so that all entries
+** are distinct.
+**
+** SRT_DistQueue Store results in priority queue pDest->iSDParm only if
+** the same record has never been stored before. The
+** index at pDest->iSDParm+1 hold all prior stores.
+*/
+#define SRT_Union 1 /* Store result as keys in an index */
+#define SRT_Except 2 /* Remove result from a UNION index */
+#define SRT_Exists 3 /* Store 1 if the result is not empty */
+#define SRT_Discard 4 /* Do not save the results anywhere */
+#define SRT_Fifo 5 /* Store result as data with an automatic rowid */
+#define SRT_DistFifo 6 /* Like SRT_Fifo, but unique results only */
+#define SRT_Queue 7 /* Store result in an queue */
+#define SRT_DistQueue 8 /* Like SRT_Queue, but unique results only */
+
+/* The ORDER BY clause is ignored for all of the above */
+#define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)
+
+#define SRT_Output 9 /* Output each row of result */
+#define SRT_Mem 10 /* Store result in a memory cell */
+#define SRT_Set 11 /* Store results as keys in an index */
+#define SRT_EphemTab 12 /* Create transient tab and store like SRT_Table */
+#define SRT_Coroutine 13 /* Generate a single row of result */
+#define SRT_Table 14 /* Store result as data with an automatic rowid */
+
+/*
+** An instance of this object describes where to put of the results of
+** a SELECT statement.
+*/
+struct SelectDest {
+ u8 eDest; /* How to dispose of the results. On of SRT_* above. */
+ char affSdst; /* Affinity used when eDest==SRT_Set */
+ int iSDParm; /* A parameter used by the eDest disposal method */
+ int iSdst; /* Base register where results are written */
+ int nSdst; /* Number of registers allocated */
+ ExprList *pOrderBy; /* Key columns for SRT_Queue and SRT_DistQueue */
+};
+
+/*
+** During code generation of statements that do inserts into AUTOINCREMENT
+** tables, the following information is attached to the Table.u.autoInc.p
+** pointer of each autoincrement table to record some side information that
+** the code generator needs. We have to keep per-table autoincrement
+** information in case inserts are down within triggers. Triggers do not
+** normally coordinate their activities, but we do need to coordinate the
+** loading and saving of autoincrement information.
+*/
+struct AutoincInfo {
+ AutoincInfo *pNext; /* Next info block in a list of them all */
+ Table *pTab; /* Table this info block refers to */
+ int iDb; /* Index in sqlite3.aDb[] of database holding pTab */
+ int regCtr; /* Memory register holding the rowid counter */
+};
+
+/*
+** Size of the column cache
+*/
+#ifndef SQLITE_N_COLCACHE
+# define SQLITE_N_COLCACHE 10
+#endif
+
+/*
+** At least one instance of the following structure is created for each
+** trigger that may be fired while parsing an INSERT, UPDATE or DELETE
+** statement. All such objects are stored in the linked list headed at
+** Parse.pTriggerPrg and deleted once statement compilation has been
+** completed.
+**
+** A Vdbe sub-program that implements the body and WHEN clause of trigger
+** TriggerPrg.pTrigger, assuming a default ON CONFLICT clause of
+** TriggerPrg.orconf, is stored in the TriggerPrg.pProgram variable.
+** The Parse.pTriggerPrg list never contains two entries with the same
+** values for both pTrigger and orconf.
+**
+** The TriggerPrg.aColmask[0] variable is set to a mask of old.* columns
+** accessed (or set to 0 for triggers fired as a result of INSERT
+** statements). Similarly, the TriggerPrg.aColmask[1] variable is set to
+** a mask of new.* columns used by the program.
+*/
+struct TriggerPrg {
+ Trigger *pTrigger; /* Trigger this program was coded from */
+ TriggerPrg *pNext; /* Next entry in Parse.pTriggerPrg list */
+ SubProgram *pProgram; /* Program implementing pTrigger/orconf */
+ int orconf; /* Default ON CONFLICT policy */
+ u32 aColmask[2]; /* Masks of old.*, new.* columns accessed */
+};
+
+/*
+** The yDbMask datatype for the bitmask of all attached databases.
+*/
+#if SQLITE_MAX_ATTACHED>30
+ typedef sqlite3_uint64 yDbMask;
+#else
+ typedef unsigned int yDbMask;
+#endif
+
+/*
+** An SQL parser context. A copy of this structure is passed through
+** the parser and down into all the parser action routine in order to
+** carry around information that is global to the entire parse.
+**
+** The structure is divided into two parts. When the parser and code
+** generate call themselves recursively, the first part of the structure
+** is constant but the second part is reset at the beginning and end of
+** each recursion.
+**
+** The nTableLock and aTableLock variables are only used if the shared-cache
+** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
+** used to store the set of table-locks required by the statement being
+** compiled. Function sqlite3TableLock() is used to add entries to the
+** list.
+*/
+struct Parse {
+ sqlite3 *db; /* The main database structure */
+ char *zErrMsg; /* An error message */
+ Vdbe *pVdbe; /* An engine for executing database bytecode */
+ int rc; /* Return code from execution */
+ u8 colNamesSet; /* TRUE after OP_ColumnName has been issued to pVdbe */
+ u8 checkSchema; /* Causes schema cookie check after an error */
+ u8 nested; /* Number of nested calls to the parser/code generator */
+ u8 nTempReg; /* Number of temporary registers in aTempReg[] */
+ u8 isMultiWrite; /* True if statement may modify/insert multiple rows */
+ u8 mayAbort; /* True if statement may throw an ABORT exception */
+ u8 hasCompound; /* Need to invoke convertCompoundSelectToSubquery() */
+ u8 okConstFactor; /* OK to factor out constants */
+ int aTempReg[8]; /* Holding area for temporary registers */
+ int nRangeReg; /* Size of the temporary register block */
+ int iRangeReg; /* First register in temporary register block */
+ int nErr; /* Number of errors seen */
+ int nTab; /* Number of previously allocated VDBE cursors */
+ int nMem; /* Number of memory cells used so far */
+ int nSet; /* Number of sets used so far */
+ int nOnce; /* Number of OP_Once instructions so far */
+ int nOpAlloc; /* Number of slots allocated for Vdbe.aOp[] */
+ int iFixedOp; /* Never back out opcodes iFixedOp-1 or earlier */
+ int ckBase; /* Base register of data during check constraints */
+ int iPartIdxTab; /* Table corresponding to a partial index */
+ int iCacheLevel; /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
+ int iCacheCnt; /* Counter used to generate aColCache[].lru values */
+ int nLabel; /* Number of labels used */
+ int *aLabel; /* Space to hold the labels */
+ struct yColCache {
+ int iTable; /* Table cursor number */
+ i16 iColumn; /* Table column number */
+ u8 tempReg; /* iReg is a temp register that needs to be freed */
+ int iLevel; /* Nesting level */
+ int iReg; /* Reg with value of this column. 0 means none. */
+ int lru; /* Least recently used entry has the smallest value */
+ } aColCache[SQLITE_N_COLCACHE]; /* One for each column cache entry */
+ ExprList *pConstExpr;/* Constant expressions */
+ Token constraintName;/* Name of the constraint currently being parsed */
+ yDbMask writeMask; /* Start a write transaction on these databases */
+ yDbMask cookieMask; /* Bitmask of schema verified databases */
+ int cookieValue[SQLITE_MAX_ATTACHED+2]; /* Values of cookies to verify */
+ int regRowid; /* Register holding rowid of CREATE TABLE entry */
+ int regRoot; /* Register holding root page number for new objects */
+ int nMaxArg; /* Max args passed to user function by sub-program */
+#ifndef SQLITE_OMIT_SHARED_CACHE
+ int nTableLock; /* Number of locks in aTableLock */
+ TableLock *aTableLock; /* Required table locks for shared-cache mode */
+#endif
+ AutoincInfo *pAinc; /* Information about AUTOINCREMENT counters */
+
+ /* Information used while coding trigger programs. */
+ Parse *pToplevel; /* Parse structure for main program (or NULL) */
+ Table *pTriggerTab; /* Table triggers are being coded for */
+ int addrCrTab; /* Address of OP_CreateTable opcode on CREATE TABLE */
+ int addrSkipPK; /* Address of instruction to skip PRIMARY KEY index */
+ u32 nQueryLoop; /* Est number of iterations of a query (10*log2(N)) */
+ u32 oldmask; /* Mask of old.* columns referenced */
+ u32 newmask; /* Mask of new.* columns referenced */
+ u8 eTriggerOp; /* TK_UPDATE, TK_INSERT or TK_DELETE */
+ u8 eOrconf; /* Default ON CONFLICT policy for trigger steps */
+ u8 disableTriggers; /* True to disable triggers */
+
+ /************************************************************************
+ ** Above is constant between recursions. Below is reset before and after
+ ** each recursion. The boundary between these two regions is determined
+ ** using offsetof(Parse,nVar) so the nVar field must be the first field
+ ** in the recursive region.
+ ************************************************************************/
+
+ int nVar; /* Number of '?' variables seen in the SQL so far */
+ int nzVar; /* Number of available slots in azVar[] */
+ u8 iPkSortOrder; /* ASC or DESC for INTEGER PRIMARY KEY */
+ u8 bFreeWith; /* True if pWith should be freed with parser */
+ u8 explain; /* True if the EXPLAIN flag is found on the query */
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ u8 declareVtab; /* True if inside sqlite3_declare_vtab() */
+ int nVtabLock; /* Number of virtual tables to lock */
+#endif
+ int nAlias; /* Number of aliased result set columns */
+ int nHeight; /* Expression tree height of current sub-select */
+#ifndef SQLITE_OMIT_EXPLAIN
+ int iSelectId; /* ID of current select for EXPLAIN output */
+ int iNextSelectId; /* Next available select ID for EXPLAIN output */
+#endif
+ char **azVar; /* Pointers to names of parameters */
+ Vdbe *pReprepare; /* VM being reprepared (sqlite3Reprepare()) */
+ const char *zTail; /* All SQL text past the last semicolon parsed */
+ Table *pNewTable; /* A table being constructed by CREATE TABLE */
+ Trigger *pNewTrigger; /* Trigger under construct by a CREATE TRIGGER */
+ const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
+ Token sNameToken; /* Token with unqualified schema object name */
+ Token sLastToken; /* The last token parsed */
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+ Token sArg; /* Complete text of a module argument */
+ Table **apVtabLock; /* Pointer to virtual tables needing locking */
+#endif
+ Table *pZombieTab; /* List of Table objects to delete after code gen */
+ TriggerPrg *pTriggerPrg; /* Linked list of coded triggers */
+ With *pWith; /* Current WITH clause, or NULL */
+};
+
+/*
+** Return true if currently inside an sqlite3_declare_vtab() call.
+*/
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+ #define IN_DECLARE_VTAB 0
+#else
+ #define IN_DECLARE_VTAB (pParse->declareVtab)
+#endif
+
+/*
+** An instance of the following structure can be declared on a stack and used
+** to save the Parse.zAuthContext value so that it can be restored later.
+*/
+struct AuthContext {
+ const char *zAuthContext; /* Put saved Parse.zAuthContext here */
+ Parse *pParse; /* The Parse structure */
+};
+
+/*
+** Bitfield flags for P5 value in various opcodes.
+*/
+#define OPFLAG_NCHANGE 0x01 /* Set to update db->nChange */
+#define OPFLAG_LASTROWID 0x02 /* Set to update db->lastRowid */
+#define OPFLAG_ISUPDATE 0x04 /* This OP_Insert is an sql UPDATE */
+#define OPFLAG_APPEND 0x08 /* This is likely to be an append */
+#define OPFLAG_USESEEKRESULT 0x10 /* Try to avoid a seek in BtreeInsert() */
+#define OPFLAG_CLEARCACHE 0x20 /* Clear pseudo-table cache in OP_Column */
+#define OPFLAG_LENGTHARG 0x40 /* OP_Column only used for length() */
+#define OPFLAG_TYPEOFARG 0x80 /* OP_Column only used for typeof() */
+#define OPFLAG_BULKCSR 0x01 /* OP_Open** used to open bulk cursor */
+#define OPFLAG_P2ISREG 0x02 /* P2 to OP_Open** is a register number */
+#define OPFLAG_PERMUTE 0x01 /* OP_Compare: use the permutation */
+
+/*
+ * Each trigger present in the database schema is stored as an instance of
+ * struct Trigger.
+ *
+ * Pointers to instances of struct Trigger are stored in two ways.
+ * 1. In the "trigHash" hash table (part of the sqlite3* that represents the
+ * database). This allows Trigger structures to be retrieved by name.
+ * 2. All triggers associated with a single table form a linked list, using the
+ * pNext member of struct Trigger. A pointer to the first element of the
+ * linked list is stored as the "pTrigger" member of the associated
+ * struct Table.
+ *
+ * The "step_list" member points to the first element of a linked list
+ * containing the SQL statements specified as the trigger program.
+ */
+struct Trigger {
+ char *zName; /* The name of the trigger */
+ char *table; /* The table or view to which the trigger applies */
+ u8 op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT */
+ u8 tr_tm; /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
+ Expr *pWhen; /* The WHEN clause of the expression (may be NULL) */
+ IdList *pColumns; /* If this is an UPDATE OF trigger,
+ the is stored here */
+ Schema *pSchema; /* Schema containing the trigger */
+ Schema *pTabSchema; /* Schema containing the table */
+ TriggerStep *step_list; /* Link list of trigger program steps */
+ Trigger *pNext; /* Next trigger associated with the table */
+};
+
+/*
+** A trigger is either a BEFORE or an AFTER trigger. The following constants
+** determine which.
+**
+** If there are multiple triggers, you might of some BEFORE and some AFTER.
+** In that cases, the constants below can be ORed together.
+*/
+#define TRIGGER_BEFORE 1
+#define TRIGGER_AFTER 2
+
+/*
+ * An instance of struct TriggerStep is used to store a single SQL statement
+ * that is a part of a trigger-program.
+ *
+ * Instances of struct TriggerStep are stored in a singly linked list (linked
+ * using the "pNext" member) referenced by the "step_list" member of the
+ * associated struct Trigger instance. The first element of the linked list is
+ * the first step of the trigger-program.
+ *
+ * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
+ * "SELECT" statement. The meanings of the other members is determined by the
+ * value of "op" as follows:
+ *
+ * (op == TK_INSERT)
+ * orconf -> stores the ON CONFLICT algorithm
+ * pSelect -> If this is an INSERT INTO ... SELECT ... statement, then
+ * this stores a pointer to the SELECT statement. Otherwise NULL.
+ * target -> A token holding the quoted name of the table to insert into.
+ * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
+ * this stores values to be inserted. Otherwise NULL.
+ * pIdList -> If this is an INSERT INTO ... () VALUES ...
+ * statement, then this stores the column-names to be
+ * inserted into.
+ *
+ * (op == TK_DELETE)
+ * target -> A token holding the quoted name of the table to delete from.
+ * pWhere -> The WHERE clause of the DELETE statement if one is specified.
+ * Otherwise NULL.
+ *
+ * (op == TK_UPDATE)
+ * target -> A token holding the quoted name of the table to update rows of.
+ * pWhere -> The WHERE clause of the UPDATE statement if one is specified.
+ * Otherwise NULL.
+ * pExprList -> A list of the columns to update and the expressions to update
+ * them to. See sqlite3Update() documentation of "pChanges"
+ * argument.
+ *
+ */
+struct TriggerStep {
+ u8 op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
+ u8 orconf; /* OE_Rollback etc. */
+ Trigger *pTrig; /* The trigger that this step is a part of */
+ Select *pSelect; /* SELECT statment or RHS of INSERT INTO .. SELECT ... */
+ Token target; /* Target table for DELETE, UPDATE, INSERT */
+ Expr *pWhere; /* The WHERE clause for DELETE or UPDATE steps */
+ ExprList *pExprList; /* SET clause for UPDATE. */
+ IdList *pIdList; /* Column names for INSERT */
+ TriggerStep *pNext; /* Next in the link-list */
+ TriggerStep *pLast; /* Last element in link-list. Valid for 1st elem only */
+};
+
+/*
+** The following structure contains information used by the sqliteFix...
+** routines as they walk the parse tree to make database references
+** explicit.
+*/
+typedef struct DbFixer DbFixer;
+struct DbFixer {
+ Parse *pParse; /* The parsing context. Error messages written here */
+ Schema *pSchema; /* Fix items to this schema */
+ int bVarOnly; /* Check for variable references only */
+ const char *zDb; /* Make sure all objects are contained in this database */
+ const char *zType; /* Type of the container - used for error messages */
+ const Token *pName; /* Name of the container - used for error messages */
+};
+
+/*
+** An objected used to accumulate the text of a string where we
+** do not necessarily know how big the string will be in the end.
+*/
+struct StrAccum {
+ sqlite3 *db; /* Optional database for lookaside. Can be NULL */
+ char *zBase; /* A base allocation. Not from malloc. */
+ char *zText; /* The string collected so far */
+ int nChar; /* Length of the string so far */
+ int nAlloc; /* Amount of space allocated in zText */
+ int mxAlloc; /* Maximum allowed string length */
+ u8 useMalloc; /* 0: none, 1: sqlite3DbMalloc, 2: sqlite3_malloc */
+ u8 accError; /* STRACCUM_NOMEM or STRACCUM_TOOBIG */
+};
+#define STRACCUM_NOMEM 1
+#define STRACCUM_TOOBIG 2
+
+/*
+** A pointer to this structure is used to communicate information
+** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
+*/
+typedef struct {
+ sqlite3 *db; /* The database being initialized */
+ char **pzErrMsg; /* Error message stored here */
+ int iDb; /* 0 for main database. 1 for TEMP, 2.. for ATTACHed */
+ int rc; /* Result code stored here */
+} InitData;
+
+/*
+** Structure containing global configuration data for the SQLite library.
+**
+** This structure also contains some state information.
+*/
+struct Sqlite3Config {
+ int bMemstat; /* True to enable memory status */
+ int bCoreMutex; /* True to enable core mutexing */
+ int bFullMutex; /* True to enable full mutexing */
+ int bOpenUri; /* True to interpret filenames as URIs */
+ int bUseCis; /* Use covering indices for full-scans */
+ int mxStrlen; /* Maximum string length */
+ int neverCorrupt; /* Database is always well-formed */
+ int szLookaside; /* Default lookaside buffer size */
+ int nLookaside; /* Default lookaside buffer count */
+ sqlite3_mem_methods m; /* Low-level memory allocation interface */
+ sqlite3_mutex_methods mutex; /* Low-level mutex interface */
+ sqlite3_pcache_methods2 pcache2; /* Low-level page-cache interface */
+ void *pHeap; /* Heap storage space */
+ int nHeap; /* Size of pHeap[] */
+ int mnReq, mxReq; /* Min and max heap requests sizes */
+ sqlite3_int64 szMmap; /* mmap() space per open file */
+ sqlite3_int64 mxMmap; /* Maximum value for szMmap */
+ void *pScratch; /* Scratch memory */
+ int szScratch; /* Size of each scratch buffer */
+ int nScratch; /* Number of scratch buffers */
+ void *pPage; /* Page cache memory */
+ int szPage; /* Size of each page in pPage[] */
+ int nPage; /* Number of pages in pPage[] */
+ int mxParserStack; /* maximum depth of the parser stack */
+ int sharedCacheEnabled; /* true if shared-cache mode enabled */
+ /* The above might be initialized to non-zero. The following need to always
+ ** initially be zero, however. */
+ int isInit; /* True after initialization has finished */
+ int inProgress; /* True while initialization in progress */
+ int isMutexInit; /* True after mutexes are initialized */
+ int isMallocInit; /* True after malloc is initialized */
+ int isPCacheInit; /* True after malloc is initialized */
+ int nRefInitMutex; /* Number of users of pInitMutex */
+ sqlite3_mutex *pInitMutex; /* Mutex used by sqlite3_initialize() */
+ void (*xLog)(void*,int,const char*); /* Function for logging */
+ void *pLogArg; /* First argument to xLog() */
+#ifdef SQLITE_ENABLE_SQLLOG
+ void(*xSqllog)(void*,sqlite3*,const char*, int);
+ void *pSqllogArg;
+#endif
+#ifdef SQLITE_VDBE_COVERAGE
+ /* The following callback (if not NULL) is invoked on every VDBE branch
+ ** operation. Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
+ */
+ void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx); /* Callback */
+ void *pVdbeBranchArg; /* 1st argument */
+#endif
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+ int (*xTestCallback)(int); /* Invoked by sqlite3FaultSim() */
+#endif
+ int bLocaltimeFault; /* True to fail localtime() calls */
+};
+
+/*
+** This macro is used inside of assert() statements to indicate that
+** the assert is only valid on a well-formed database. Instead of:
+**
+** assert( X );
+**
+** One writes:
+**
+** assert( X || CORRUPT_DB );
+**
+** CORRUPT_DB is true during normal operation. CORRUPT_DB does not indicate
+** that the database is definitely corrupt, only that it might be corrupt.
+** For most test cases, CORRUPT_DB is set to false using a special
+** sqlite3_test_control(). This enables assert() statements to prove
+** things that are always true for well-formed databases.
+*/
+#define CORRUPT_DB (sqlite3Config.neverCorrupt==0)
+
+/*
+** Context pointer passed down through the tree-walk.
+*/
+struct Walker {
+ int (*xExprCallback)(Walker*, Expr*); /* Callback for expressions */
+ int (*xSelectCallback)(Walker*,Select*); /* Callback for SELECTs */
+ void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
+ Parse *pParse; /* Parser context. */
+ int walkerDepth; /* Number of subqueries */
+ union { /* Extra data for callback */
+ NameContext *pNC; /* Naming context */
+ int i; /* Integer value */
+ SrcList *pSrcList; /* FROM clause */
+ struct SrcCount *pSrcCount; /* Counting column references */
+ } u;
+};
+
+/* Forward declarations */
+SQLITE_PRIVATE int sqlite3WalkExpr(Walker*, Expr*);
+SQLITE_PRIVATE int sqlite3WalkExprList(Walker*, ExprList*);
+SQLITE_PRIVATE int sqlite3WalkSelect(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3WalkSelectExpr(Walker*, Select*);
+SQLITE_PRIVATE int sqlite3WalkSelectFrom(Walker*, Select*);
+
+/*
+** Return code from the parse-tree walking primitives and their
+** callbacks.
+*/
+#define WRC_Continue 0 /* Continue down into children */
+#define WRC_Prune 1 /* Omit children but continue walking siblings */
+#define WRC_Abort 2 /* Abandon the tree walk */
+
+/*
+** An instance of this structure represents a set of one or more CTEs
+** (common table expressions) created by a single WITH clause.
+*/
+struct With {
+ int nCte; /* Number of CTEs in the WITH clause */
+ With *pOuter; /* Containing WITH clause, or NULL */
+ struct Cte { /* For each CTE in the WITH clause.... */
+ char *zName; /* Name of this CTE */
+ ExprList *pCols; /* List of explicit column names, or NULL */
+ Select *pSelect; /* The definition of this CTE */
+ const char *zErr; /* Error message for circular references */
+ } a[1];
+};
+
+/*
+** Assuming zIn points to the first byte of a UTF-8 character,
+** advance zIn to point to the first byte of the next UTF-8 character.
+*/
+#define SQLITE_SKIP_UTF8(zIn) { \
+ if( (*(zIn++))>=0xc0 ){ \
+ while( (*zIn & 0xc0)==0x80 ){ zIn++; } \
+ } \
+}
+
+/*
+** The SQLITE_*_BKPT macros are substitutes for the error codes with
+** the same name but without the _BKPT suffix. These macros invoke
+** routines that report the line-number on which the error originated
+** using sqlite3_log(). The routines also provide a convenient place
+** to set a debugger breakpoint.
+*/
+SQLITE_PRIVATE int sqlite3CorruptError(int);
+SQLITE_PRIVATE int sqlite3MisuseError(int);
+SQLITE_PRIVATE int sqlite3CantopenError(int);
+#define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
+#define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
+#define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
+
+
+/*
+** FTS4 is really an extension for FTS3. It is enabled using the
+** SQLITE_ENABLE_FTS3 macro. But to avoid confusion we also all
+** the SQLITE_ENABLE_FTS4 macro to serve as an alisse for SQLITE_ENABLE_FTS3.
+*/
+#if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
+# define SQLITE_ENABLE_FTS3
+#endif
+
+/*
+** The ctype.h header is needed for non-ASCII systems. It is also
+** needed by FTS3 when FTS3 is included in the amalgamation.
+*/
+#if !defined(SQLITE_ASCII) || \
+ (defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_AMALGAMATION))
+# include
+#endif
+
+/*
+** The following macros mimic the standard library functions toupper(),
+** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
+** sqlite versions only work for ASCII characters, regardless of locale.
+*/
+#ifdef SQLITE_ASCII
+# define sqlite3Toupper(x) ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
+# define sqlite3Isspace(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
+# define sqlite3Isalnum(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
+# define sqlite3Isalpha(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
+# define sqlite3Isdigit(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
+# define sqlite3Isxdigit(x) (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
+# define sqlite3Tolower(x) (sqlite3UpperToLower[(unsigned char)(x)])
+#else
+# define sqlite3Toupper(x) toupper((unsigned char)(x))
+# define sqlite3Isspace(x) isspace((unsigned char)(x))
+# define sqlite3Isalnum(x) isalnum((unsigned char)(x))
+# define sqlite3Isalpha(x) isalpha((unsigned char)(x))
+# define sqlite3Isdigit(x) isdigit((unsigned char)(x))
+# define sqlite3Isxdigit(x) isxdigit((unsigned char)(x))
+# define sqlite3Tolower(x) tolower((unsigned char)(x))
+#endif
+
+/*
+** Internal function prototypes
+*/
+#define sqlite3StrICmp sqlite3_stricmp
+SQLITE_PRIVATE int sqlite3Strlen30(const char*);
+#define sqlite3StrNICmp sqlite3_strnicmp
+
+SQLITE_PRIVATE int sqlite3MallocInit(void);
+SQLITE_PRIVATE void sqlite3MallocEnd(void);
+SQLITE_PRIVATE void *sqlite3Malloc(int);
+SQLITE_PRIVATE void *sqlite3MallocZero(int);
+SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3*, int);
+SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3*, int);
+SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3*,const char*);
+SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3*,const char*, int);
+SQLITE_PRIVATE void *sqlite3Realloc(void*, int);
+SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
+SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *, void *, int);
+SQLITE_PRIVATE void sqlite3DbFree(sqlite3*, void*);
+SQLITE_PRIVATE int sqlite3MallocSize(void*);
+SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3*, void*);
+SQLITE_PRIVATE void *sqlite3ScratchMalloc(int);
+SQLITE_PRIVATE void sqlite3ScratchFree(void*);
+SQLITE_PRIVATE void *sqlite3PageMalloc(int);
+SQLITE_PRIVATE void sqlite3PageFree(void*);
+SQLITE_PRIVATE void sqlite3MemSetDefault(void);
+SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void);
+
+/*
+** On systems with ample stack space and that support alloca(), make
+** use of alloca() to obtain space for large automatic objects. By default,
+** obtain space from malloc().
+**
+** The alloca() routine never returns NULL. This will cause code paths
+** that deal with sqlite3StackAlloc() failures to be unreachable.
+*/
+#ifdef SQLITE_USE_ALLOCA
+# define sqlite3StackAllocRaw(D,N) alloca(N)
+# define sqlite3StackAllocZero(D,N) memset(alloca(N), 0, N)
+# define sqlite3StackFree(D,P)
+#else
+# define sqlite3StackAllocRaw(D,N) sqlite3DbMallocRaw(D,N)
+# define sqlite3StackAllocZero(D,N) sqlite3DbMallocZero(D,N)
+# define sqlite3StackFree(D,P) sqlite3DbFree(D,P)
+#endif
+
+#ifdef SQLITE_ENABLE_MEMSYS3
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
+#endif
+#ifdef SQLITE_ENABLE_MEMSYS5
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
+#endif
+
+
+#ifndef SQLITE_MUTEX_OMIT
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void);
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3NoopMutex(void);
+SQLITE_PRIVATE sqlite3_mutex *sqlite3MutexAlloc(int);
+SQLITE_PRIVATE int sqlite3MutexInit(void);
+SQLITE_PRIVATE int sqlite3MutexEnd(void);
+#endif
+
+SQLITE_PRIVATE int sqlite3StatusValue(int);
+SQLITE_PRIVATE void sqlite3StatusAdd(int, int);
+SQLITE_PRIVATE void sqlite3StatusSet(int, int);
+
+#ifndef SQLITE_OMIT_FLOATING_POINT
+SQLITE_PRIVATE int sqlite3IsNaN(double);
+#else
+# define sqlite3IsNaN(X) 0
+#endif
+
+/*
+** An instance of the following structure holds information about SQL
+** functions arguments that are the parameters to the printf() function.
+*/
+struct PrintfArguments {
+ int nArg; /* Total number of arguments */
+ int nUsed; /* Number of arguments used so far */
+ sqlite3_value **apArg; /* The argument values */
+};
+
+#define SQLITE_PRINTF_INTERNAL 0x01
+#define SQLITE_PRINTF_SQLFUNC 0x02
+SQLITE_PRIVATE void sqlite3VXPrintf(StrAccum*, u32, const char*, va_list);
+SQLITE_PRIVATE void sqlite3XPrintf(StrAccum*, u32, const char*, ...);
+SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3*,const char*, ...);
+SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
+SQLITE_PRIVATE char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
+#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
+SQLITE_PRIVATE void sqlite3DebugPrintf(const char*, ...);
+#endif
+#if defined(SQLITE_TEST)
+SQLITE_PRIVATE void *sqlite3TestTextToPtr(const char*);
+#endif
+
+/* Output formatting for SQLITE_TESTCTRL_EXPLAIN */
+#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
+SQLITE_PRIVATE void sqlite3ExplainBegin(Vdbe*);
+SQLITE_PRIVATE void sqlite3ExplainPrintf(Vdbe*, const char*, ...);
+SQLITE_PRIVATE void sqlite3ExplainNL(Vdbe*);
+SQLITE_PRIVATE void sqlite3ExplainPush(Vdbe*);
+SQLITE_PRIVATE void sqlite3ExplainPop(Vdbe*);
+SQLITE_PRIVATE void sqlite3ExplainFinish(Vdbe*);
+SQLITE_PRIVATE void sqlite3ExplainSelect(Vdbe*, Select*);
+SQLITE_PRIVATE void sqlite3ExplainExpr(Vdbe*, Expr*);
+SQLITE_PRIVATE void sqlite3ExplainExprList(Vdbe*, ExprList*);
+SQLITE_PRIVATE const char *sqlite3VdbeExplanation(Vdbe*);
+#else
+# define sqlite3ExplainBegin(X)
+# define sqlite3ExplainSelect(A,B)
+# define sqlite3ExplainExpr(A,B)
+# define sqlite3ExplainExprList(A,B)
+# define sqlite3ExplainFinish(X)
+# define sqlite3VdbeExplanation(X) 0
+#endif
+
+
+SQLITE_PRIVATE void sqlite3SetString(char **, sqlite3*, const char*, ...);
+SQLITE_PRIVATE void sqlite3ErrorMsg(Parse*, const char*, ...);
+SQLITE_PRIVATE int sqlite3Dequote(char*);
+SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char*, int);
+SQLITE_PRIVATE int sqlite3RunParser(Parse*, const char*, char **);
+SQLITE_PRIVATE void sqlite3FinishCoding(Parse*);
+SQLITE_PRIVATE int sqlite3GetTempReg(Parse*);
+SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse*,int);
+SQLITE_PRIVATE int sqlite3GetTempRange(Parse*,int);
+SQLITE_PRIVATE void sqlite3ReleaseTempRange(Parse*,int,int);
+SQLITE_PRIVATE void sqlite3ClearTempRegCache(Parse*);
+SQLITE_PRIVATE Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
+SQLITE_PRIVATE Expr *sqlite3Expr(sqlite3*,int,const char*);
+SQLITE_PRIVATE void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
+SQLITE_PRIVATE Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
+SQLITE_PRIVATE Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
+SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
+SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse*, Expr*);
+SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3*, Expr*);
+SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
+SQLITE_PRIVATE void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
+SQLITE_PRIVATE void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
+SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3*, ExprList*);
+SQLITE_PRIVATE int sqlite3Init(sqlite3*, char**);
+SQLITE_PRIVATE int sqlite3InitCallback(void*, int, char**, char**);
+SQLITE_PRIVATE void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
+SQLITE_PRIVATE void sqlite3ResetAllSchemasOfConnection(sqlite3*);
+SQLITE_PRIVATE void sqlite3ResetOneSchema(sqlite3*,int);
+SQLITE_PRIVATE void sqlite3CollapseDatabaseArray(sqlite3*);
+SQLITE_PRIVATE void sqlite3BeginParse(Parse*,int);
+SQLITE_PRIVATE void sqlite3CommitInternalChanges(sqlite3*);
+SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse*,Select*);
+SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *, int);
+SQLITE_PRIVATE Index *sqlite3PrimaryKeyIndex(Table*);
+SQLITE_PRIVATE i16 sqlite3ColumnOfIndex(Index*, i16);
+SQLITE_PRIVATE void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
+SQLITE_PRIVATE void sqlite3AddColumn(Parse*,Token*);
+SQLITE_PRIVATE void sqlite3AddNotNull(Parse*, int);
+SQLITE_PRIVATE void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
+SQLITE_PRIVATE void sqlite3AddCheckConstraint(Parse*, Expr*);
+SQLITE_PRIVATE void sqlite3AddColumnType(Parse*,Token*);
+SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse*,ExprSpan*);
+SQLITE_PRIVATE void sqlite3AddCollateType(Parse*, Token*);
+SQLITE_PRIVATE void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
+SQLITE_PRIVATE int sqlite3ParseUri(const char*,const char*,unsigned int*,
+ sqlite3_vfs**,char**,char **);
+SQLITE_PRIVATE Btree *sqlite3DbNameToBtree(sqlite3*,const char*);
+SQLITE_PRIVATE int sqlite3CodeOnce(Parse *);
+
+#ifdef SQLITE_OMIT_BUILTIN_TEST
+# define sqlite3FaultSim(X) SQLITE_OK
+#else
+SQLITE_PRIVATE int sqlite3FaultSim(int);
+#endif
+
+SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32);
+SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec*, u32);
+SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec*, u32);
+SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec*, u32, void*);
+SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec*);
+SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec*);
+SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int,int*);
+
+SQLITE_PRIVATE RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
+SQLITE_PRIVATE void sqlite3RowSetClear(RowSet*);
+SQLITE_PRIVATE void sqlite3RowSetInsert(RowSet*, i64);
+SQLITE_PRIVATE int sqlite3RowSetTest(RowSet*, int iBatch, i64);
+SQLITE_PRIVATE int sqlite3RowSetNext(RowSet*, i64*);
+
+SQLITE_PRIVATE void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);
+
+#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
+SQLITE_PRIVATE int sqlite3ViewGetColumnNames(Parse*,Table*);
+#else
+# define sqlite3ViewGetColumnNames(A,B) 0
+#endif
+
+SQLITE_PRIVATE void sqlite3DropTable(Parse*, SrcList*, int, int);
+SQLITE_PRIVATE void sqlite3CodeDropTable(Parse*, Table*, int, int);
+SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3*, Table*);
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+SQLITE_PRIVATE void sqlite3AutoincrementBegin(Parse *pParse);
+SQLITE_PRIVATE void sqlite3AutoincrementEnd(Parse *pParse);
+#else
+# define sqlite3AutoincrementBegin(X)
+# define sqlite3AutoincrementEnd(X)
+#endif
+SQLITE_PRIVATE void sqlite3Insert(Parse*, SrcList*, Select*, IdList*, int);
+SQLITE_PRIVATE void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
+SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
+SQLITE_PRIVATE int sqlite3IdListIndex(IdList*,const char*);
+SQLITE_PRIVATE SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
+SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
+SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
+ Token*, Select*, Expr*, IdList*);
+SQLITE_PRIVATE void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
+SQLITE_PRIVATE int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
+SQLITE_PRIVATE void sqlite3SrcListShiftJoinType(SrcList*);
+SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse*, SrcList*);
+SQLITE_PRIVATE void sqlite3IdListDelete(sqlite3*, IdList*);
+SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3*, SrcList*);
+SQLITE_PRIVATE Index *sqlite3AllocateIndexObject(sqlite3*,i16,int,char**);
+SQLITE_PRIVATE Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
+ Expr*, int, int);
+SQLITE_PRIVATE void sqlite3DropIndex(Parse*, SrcList*, int);
+SQLITE_PRIVATE int sqlite3Select(Parse*, Select*, SelectDest*);
+SQLITE_PRIVATE Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
+ Expr*,ExprList*,u16,Expr*,Expr*);
+SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3*, Select*);
+SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse*, SrcList*);
+SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, int);
+SQLITE_PRIVATE void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
+#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
+SQLITE_PRIVATE Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
+#endif
+SQLITE_PRIVATE void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
+SQLITE_PRIVATE void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
+SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
+SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo*);
+SQLITE_PRIVATE u64 sqlite3WhereOutputRowCount(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsDistinct(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsOrdered(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsSorted(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereContinueLabel(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereBreakLabel(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereOkOnePass(WhereInfo*, int*);
+SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
+SQLITE_PRIVATE void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCacheStore(Parse*, int, int, int);
+SQLITE_PRIVATE void sqlite3ExprCachePush(Parse*);
+SQLITE_PRIVATE void sqlite3ExprCachePop(Parse*);
+SQLITE_PRIVATE void sqlite3ExprCacheRemove(Parse*, int, int);
+SQLITE_PRIVATE void sqlite3ExprCacheClear(Parse*);
+SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse*, int, int);
+SQLITE_PRIVATE void sqlite3ExprCode(Parse*, Expr*, int);
+SQLITE_PRIVATE void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
+SQLITE_PRIVATE void sqlite3ExprCodeAtInit(Parse*, Expr*, int, u8);
+SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
+SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse*, Expr*, int);
+SQLITE_PRIVATE void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprCodeExprList(Parse*, ExprList*, int, u8);
+#define SQLITE_ECEL_DUP 0x01 /* Deep, not shallow copies */
+#define SQLITE_ECEL_FACTOR 0x02 /* Factor out constant terms */
+SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
+SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
+SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3*,const char*, const char*);
+SQLITE_PRIVATE Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
+SQLITE_PRIVATE Table *sqlite3LocateTableItem(Parse*,int isView,struct SrcList_item *);
+SQLITE_PRIVATE Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
+SQLITE_PRIVATE void sqlite3Vacuum(Parse*);
+SQLITE_PRIVATE int sqlite3RunVacuum(char**, sqlite3*);
+SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3*, Token*);
+SQLITE_PRIVATE int sqlite3ExprCompare(Expr*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList*, ExprList*, int);
+SQLITE_PRIVATE int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
+SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
+SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
+SQLITE_PRIVATE int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
+SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse*);
+SQLITE_PRIVATE void sqlite3PrngSaveState(void);
+SQLITE_PRIVATE void sqlite3PrngRestoreState(void);
+SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3*,int);
+SQLITE_PRIVATE void sqlite3CodeVerifySchema(Parse*, int);
+SQLITE_PRIVATE void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
+SQLITE_PRIVATE void sqlite3BeginTransaction(Parse*, int);
+SQLITE_PRIVATE void sqlite3CommitTransaction(Parse*);
+SQLITE_PRIVATE void sqlite3RollbackTransaction(Parse*);
+SQLITE_PRIVATE void sqlite3Savepoint(Parse*, int, Token*);
+SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *);
+SQLITE_PRIVATE void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
+SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr*);
+SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
+SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*);
+SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr*, int*);
+SQLITE_PRIVATE int sqlite3ExprCanBeNull(const Expr*);
+SQLITE_PRIVATE int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
+SQLITE_PRIVATE int sqlite3IsRowid(const char*);
+SQLITE_PRIVATE void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
+SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
+SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
+SQLITE_PRIVATE void sqlite3ResolvePartIdxLabel(Parse*,int);
+SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
+ u8,u8,int,int*);
+SQLITE_PRIVATE void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
+SQLITE_PRIVATE int sqlite3OpenTableAndIndices(Parse*, Table*, int, int, u8*, int*, int*);
+SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse*, int, int);
+SQLITE_PRIVATE void sqlite3MultiWrite(Parse*);
+SQLITE_PRIVATE void sqlite3MayAbort(Parse*);
+SQLITE_PRIVATE void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
+SQLITE_PRIVATE void sqlite3UniqueConstraint(Parse*, int, Index*);
+SQLITE_PRIVATE void sqlite3RowidConstraint(Parse*, int, Table*);
+SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
+SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
+SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
+SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3*,IdList*);
+SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3*,Select*,int);
+SQLITE_PRIVATE void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
+SQLITE_PRIVATE FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
+SQLITE_PRIVATE void sqlite3RegisterBuiltinFunctions(sqlite3*);
+SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(void);
+SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void);
+SQLITE_PRIVATE int sqlite3SafetyCheckOk(sqlite3*);
+SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3*);
+SQLITE_PRIVATE void sqlite3ChangeCookie(Parse*, int);
+
+#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
+SQLITE_PRIVATE void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
+#endif
+
+#ifndef SQLITE_OMIT_TRIGGER
+SQLITE_PRIVATE void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
+ Expr*,int, int);
+SQLITE_PRIVATE void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
+SQLITE_PRIVATE void sqlite3DropTrigger(Parse*, SrcList*, int);
+SQLITE_PRIVATE void sqlite3DropTriggerPtr(Parse*, Trigger*);
+SQLITE_PRIVATE Trigger *sqlite3TriggersExist(Parse *, Table*, int, ExprList*, int *pMask);
+SQLITE_PRIVATE Trigger *sqlite3TriggerList(Parse *, Table *);
+SQLITE_PRIVATE void sqlite3CodeRowTrigger(Parse*, Trigger *, int, ExprList*, int, Table *,
+ int, int, int);
+SQLITE_PRIVATE void sqlite3CodeRowTriggerDirect(Parse *, Trigger *, Table *, int, int, int);
+ void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
+SQLITE_PRIVATE void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
+ Select*,u8);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, u8);
+SQLITE_PRIVATE TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
+SQLITE_PRIVATE void sqlite3DeleteTrigger(sqlite3*, Trigger*);
+SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
+SQLITE_PRIVATE u32 sqlite3TriggerColmask(Parse*,Trigger*,ExprList*,int,int,Table*,int);
+# define sqlite3ParseToplevel(p) ((p)->pToplevel ? (p)->pToplevel : (p))
+#else
+# define sqlite3TriggersExist(B,C,D,E,F) 0
+# define sqlite3DeleteTrigger(A,B)
+# define sqlite3DropTriggerPtr(A,B)
+# define sqlite3UnlinkAndDeleteTrigger(A,B,C)
+# define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I)
+# define sqlite3CodeRowTriggerDirect(A,B,C,D,E,F)
+# define sqlite3TriggerList(X, Y) 0
+# define sqlite3ParseToplevel(p) p
+# define sqlite3TriggerColmask(A,B,C,D,E,F,G) 0
+#endif
+
+SQLITE_PRIVATE int sqlite3JoinType(Parse*, Token*, Token*, Token*);
+SQLITE_PRIVATE void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
+SQLITE_PRIVATE void sqlite3DeferForeignKey(Parse*, int);
+#ifndef SQLITE_OMIT_AUTHORIZATION
+SQLITE_PRIVATE void sqlite3AuthRead(Parse*,Expr*,Schema*,SrcList*);
+SQLITE_PRIVATE int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
+SQLITE_PRIVATE void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
+SQLITE_PRIVATE void sqlite3AuthContextPop(AuthContext*);
+SQLITE_PRIVATE int sqlite3AuthReadCol(Parse*, const char *, const char *, int);
+#else
+# define sqlite3AuthRead(a,b,c,d)
+# define sqlite3AuthCheck(a,b,c,d,e) SQLITE_OK
+# define sqlite3AuthContextPush(a,b,c)
+# define sqlite3AuthContextPop(a) ((void)(a))
+#endif
+SQLITE_PRIVATE void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
+SQLITE_PRIVATE void sqlite3Detach(Parse*, Expr*);
+SQLITE_PRIVATE void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
+SQLITE_PRIVATE int sqlite3FixSrcList(DbFixer*, SrcList*);
+SQLITE_PRIVATE int sqlite3FixSelect(DbFixer*, Select*);
+SQLITE_PRIVATE int sqlite3FixExpr(DbFixer*, Expr*);
+SQLITE_PRIVATE int sqlite3FixExprList(DbFixer*, ExprList*);
+SQLITE_PRIVATE int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
+SQLITE_PRIVATE int sqlite3AtoF(const char *z, double*, int, u8);
+SQLITE_PRIVATE int sqlite3GetInt32(const char *, int*);
+SQLITE_PRIVATE int sqlite3Atoi(const char*);
+SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *pData, int nChar);
+SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *pData, int nByte);
+SQLITE_PRIVATE u32 sqlite3Utf8Read(const u8**);
+SQLITE_PRIVATE LogEst sqlite3LogEst(u64);
+SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst,LogEst);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double);
+#endif
+SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst);
+
+/*
+** Routines to read and write variable-length integers. These used to
+** be defined locally, but now we use the varint routines in the util.c
+** file. Code should use the MACRO forms below, as the Varint32 versions
+** are coded to assume the single byte case is already handled (which
+** the MACRO form does).
+*/
+SQLITE_PRIVATE int sqlite3PutVarint(unsigned char*, u64);
+SQLITE_PRIVATE int sqlite3PutVarint32(unsigned char*, u32);
+SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *, u64 *);
+SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *, u32 *);
+SQLITE_PRIVATE int sqlite3VarintLen(u64 v);
+
+/*
+** The header of a record consists of a sequence variable-length integers.
+** These integers are almost always small and are encoded as a single byte.
+** The following macros take advantage this fact to provide a fast encode
+** and decode of the integers in a record header. It is faster for the common
+** case where the integer is a single byte. It is a little slower when the
+** integer is two or more bytes. But overall it is faster.
+**
+** The following expressions are equivalent:
+**
+** x = sqlite3GetVarint32( A, &B );
+** x = sqlite3PutVarint32( A, B );
+**
+** x = getVarint32( A, B );
+** x = putVarint32( A, B );
+**
+*/
+#define getVarint32(A,B) \
+ (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
+#define putVarint32(A,B) \
+ (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
+ sqlite3PutVarint32((A),(B)))
+#define getVarint sqlite3GetVarint
+#define putVarint sqlite3PutVarint
+
+
+SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
+SQLITE_PRIVATE void sqlite3TableAffinity(Vdbe*, Table*, int);
+SQLITE_PRIVATE char sqlite3CompareAffinity(Expr *pExpr, char aff2);
+SQLITE_PRIVATE int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
+SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr);
+SQLITE_PRIVATE int sqlite3Atoi64(const char*, i64*, int, u8);
+SQLITE_PRIVATE void sqlite3Error(sqlite3*, int, const char*,...);
+SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
+SQLITE_PRIVATE u8 sqlite3HexToInt(int h);
+SQLITE_PRIVATE int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
+
+#if defined(SQLITE_TEST)
+SQLITE_PRIVATE const char *sqlite3ErrName(int);
+#endif
+
+SQLITE_PRIVATE const char *sqlite3ErrStr(int);
+SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse);
+SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
+SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
+SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*);
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
+SQLITE_PRIVATE Expr *sqlite3ExprSkipCollate(Expr*);
+SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *, CollSeq *);
+SQLITE_PRIVATE int sqlite3CheckObjectName(Parse *, const char *);
+SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *, int);
+SQLITE_PRIVATE int sqlite3AddInt64(i64*,i64);
+SQLITE_PRIVATE int sqlite3SubInt64(i64*,i64);
+SQLITE_PRIVATE int sqlite3MulInt64(i64*,i64);
+SQLITE_PRIVATE int sqlite3AbsInt32(int);
+#ifdef SQLITE_ENABLE_8_3_NAMES
+SQLITE_PRIVATE void sqlite3FileSuffix3(const char*, char*);
+#else
+# define sqlite3FileSuffix3(X,Y)
+#endif
+SQLITE_PRIVATE u8 sqlite3GetBoolean(const char *z,int);
+
+SQLITE_PRIVATE const void *sqlite3ValueText(sqlite3_value*, u8);
+SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value*, u8);
+SQLITE_PRIVATE void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8,
+ void(*)(void*));
+SQLITE_PRIVATE void sqlite3ValueSetNull(sqlite3_value*);
+SQLITE_PRIVATE void sqlite3ValueFree(sqlite3_value*);
+SQLITE_PRIVATE sqlite3_value *sqlite3ValueNew(sqlite3 *);
+SQLITE_PRIVATE char *sqlite3Utf16to8(sqlite3 *, const void*, int, u8);
+SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, Expr *, u8, u8, sqlite3_value **);
+SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
+#ifndef SQLITE_AMALGAMATION
+SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
+SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
+SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
+SQLITE_PRIVATE const Token sqlite3IntTokens[];
+SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;
+SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
+#ifndef SQLITE_OMIT_WSD
+SQLITE_PRIVATE int sqlite3PendingByte;
+#endif
+#endif
+SQLITE_PRIVATE void sqlite3RootPageMoved(sqlite3*, int, int, int);
+SQLITE_PRIVATE void sqlite3Reindex(Parse*, Token*, Token*);
+SQLITE_PRIVATE void sqlite3AlterFunctions(void);
+SQLITE_PRIVATE void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
+SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *, int *);
+SQLITE_PRIVATE void sqlite3NestedParse(Parse*, const char*, ...);
+SQLITE_PRIVATE void sqlite3ExpirePreparedStatements(sqlite3*);
+SQLITE_PRIVATE int sqlite3CodeSubselect(Parse *, Expr *, int, int);
+SQLITE_PRIVATE void sqlite3SelectPrep(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
+SQLITE_PRIVATE int sqlite3ResolveExprNames(NameContext*, Expr*);
+SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
+SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
+SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
+SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
+SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
+SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
+SQLITE_PRIVATE char sqlite3AffinityType(const char*, u8*);
+SQLITE_PRIVATE void sqlite3Analyze(Parse*, Token*, Token*);
+SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler*);
+SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
+SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
+SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3*,Index*);
+SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
+SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3*, int);
+SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
+SQLITE_PRIVATE void sqlite3MinimumFileFormat(Parse*, int, int);
+SQLITE_PRIVATE void sqlite3SchemaClear(void *);
+SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
+SQLITE_PRIVATE int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
+SQLITE_PRIVATE void sqlite3KeyInfoUnref(KeyInfo*);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE int sqlite3KeyInfoIsWriteable(KeyInfo*);
+#endif
+SQLITE_PRIVATE int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
+ void (*)(sqlite3_context*,int,sqlite3_value **),
+ void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
+ FuncDestructor *pDestructor
+);
+SQLITE_PRIVATE int sqlite3ApiExit(sqlite3 *db, int);
+SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *);
+
+SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum*, char*, int, int);
+SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum*,const char*,int);
+SQLITE_PRIVATE void sqlite3StrAccumAppendAll(StrAccum*,const char*);
+SQLITE_PRIVATE void sqlite3AppendSpace(StrAccum*,int);
+SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum*);
+SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum*);
+SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest*,int,int);
+SQLITE_PRIVATE Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
+
+SQLITE_PRIVATE void sqlite3BackupRestart(sqlite3_backup *);
+SQLITE_PRIVATE void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
+
+#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
+SQLITE_PRIVATE void sqlite3AnalyzeFunctions(void);
+SQLITE_PRIVATE int sqlite3Stat4ProbeSetValue(Parse*,Index*,UnpackedRecord**,Expr*,u8,int,int*);
+SQLITE_PRIVATE void sqlite3Stat4ProbeFree(UnpackedRecord*);
+#endif
+
+/*
+** The interface to the LEMON-generated parser
+*/
+SQLITE_PRIVATE void *sqlite3ParserAlloc(void*(*)(size_t));
+SQLITE_PRIVATE void sqlite3ParserFree(void*, void(*)(void*));
+SQLITE_PRIVATE void sqlite3Parser(void*, int, Token, Parse*);
+#ifdef YYTRACKMAXSTACKDEPTH
+SQLITE_PRIVATE int sqlite3ParserStackPeak(void*);
+#endif
+
+SQLITE_PRIVATE void sqlite3AutoLoadExtensions(sqlite3*);
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+SQLITE_PRIVATE void sqlite3CloseExtensions(sqlite3*);
+#else
+# define sqlite3CloseExtensions(X)
+#endif
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3TableLock(Parse *, int, int, u8, const char *);
+#else
+ #define sqlite3TableLock(v,w,x,y,z)
+#endif
+
+#ifdef SQLITE_TEST
+SQLITE_PRIVATE int sqlite3Utf8To8(unsigned char*);
+#endif
+
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+# define sqlite3VtabClear(Y)
+# define sqlite3VtabSync(X,Y) SQLITE_OK
+# define sqlite3VtabRollback(X)
+# define sqlite3VtabCommit(X)
+# define sqlite3VtabInSync(db) 0
+# define sqlite3VtabLock(X)
+# define sqlite3VtabUnlock(X)
+# define sqlite3VtabUnlockList(X)
+# define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
+# define sqlite3GetVTable(X,Y) ((VTable*)0)
+#else
+SQLITE_PRIVATE void sqlite3VtabClear(sqlite3 *db, Table*);
+SQLITE_PRIVATE void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
+SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, Vdbe*);
+SQLITE_PRIVATE int sqlite3VtabRollback(sqlite3 *db);
+SQLITE_PRIVATE int sqlite3VtabCommit(sqlite3 *db);
+SQLITE_PRIVATE void sqlite3VtabLock(VTable *);
+SQLITE_PRIVATE void sqlite3VtabUnlock(VTable *);
+SQLITE_PRIVATE void sqlite3VtabUnlockList(sqlite3*);
+SQLITE_PRIVATE int sqlite3VtabSavepoint(sqlite3 *, int, int);
+SQLITE_PRIVATE void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
+SQLITE_PRIVATE VTable *sqlite3GetVTable(sqlite3*, Table*);
+# define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
+#endif
+SQLITE_PRIVATE void sqlite3VtabMakeWritable(Parse*,Table*);
+SQLITE_PRIVATE void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
+SQLITE_PRIVATE void sqlite3VtabFinishParse(Parse*, Token*);
+SQLITE_PRIVATE void sqlite3VtabArgInit(Parse*);
+SQLITE_PRIVATE void sqlite3VtabArgExtend(Parse*, Token*);
+SQLITE_PRIVATE int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
+SQLITE_PRIVATE int sqlite3VtabCallConnect(Parse*, Table*);
+SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
+SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *, VTable *);
+SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
+SQLITE_PRIVATE void sqlite3InvalidFunction(sqlite3_context*,int,sqlite3_value**);
+SQLITE_PRIVATE sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
+SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
+SQLITE_PRIVATE int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
+SQLITE_PRIVATE void sqlite3ParserReset(Parse*);
+SQLITE_PRIVATE int sqlite3Reprepare(Vdbe*);
+SQLITE_PRIVATE void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
+SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
+SQLITE_PRIVATE int sqlite3TempInMemory(const sqlite3*);
+SQLITE_PRIVATE const char *sqlite3JournalModename(int);
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
+SQLITE_PRIVATE int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
+#endif
+#ifndef SQLITE_OMIT_CTE
+SQLITE_PRIVATE With *sqlite3WithAdd(Parse*,With*,Token*,ExprList*,Select*);
+SQLITE_PRIVATE void sqlite3WithDelete(sqlite3*,With*);
+SQLITE_PRIVATE void sqlite3WithPush(Parse*, With*, u8);
+#else
+#define sqlite3WithPush(x,y,z)
+#define sqlite3WithDelete(x,y)
+#endif
+
+/* Declarations for functions in fkey.c. All of these are replaced by
+** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
+** key functionality is available. If OMIT_TRIGGER is defined but
+** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
+** this case foreign keys are parsed, but no other functionality is
+** provided (enforcement of FK constraints requires the triggers sub-system).
+*/
+#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
+SQLITE_PRIVATE void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
+SQLITE_PRIVATE void sqlite3FkDropTable(Parse*, SrcList *, Table*);
+SQLITE_PRIVATE void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
+SQLITE_PRIVATE int sqlite3FkRequired(Parse*, Table*, int*, int);
+SQLITE_PRIVATE u32 sqlite3FkOldmask(Parse*, Table*);
+SQLITE_PRIVATE FKey *sqlite3FkReferences(Table *);
+#else
+ #define sqlite3FkActions(a,b,c,d,e,f)
+ #define sqlite3FkCheck(a,b,c,d,e,f)
+ #define sqlite3FkDropTable(a,b,c)
+ #define sqlite3FkOldmask(a,b) 0
+ #define sqlite3FkRequired(a,b,c,d) 0
+#endif
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE void sqlite3FkDelete(sqlite3 *, Table*);
+SQLITE_PRIVATE int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
+#else
+ #define sqlite3FkDelete(a,b)
+ #define sqlite3FkLocateIndex(a,b,c,d,e)
+#endif
+
+
+/*
+** Available fault injectors. Should be numbered beginning with 0.
+*/
+#define SQLITE_FAULTINJECTOR_MALLOC 0
+#define SQLITE_FAULTINJECTOR_COUNT 1
+
+/*
+** The interface to the code in fault.c used for identifying "benign"
+** malloc failures. This is only present if SQLITE_OMIT_BUILTIN_TEST
+** is not defined.
+*/
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+SQLITE_PRIVATE void sqlite3BeginBenignMalloc(void);
+SQLITE_PRIVATE void sqlite3EndBenignMalloc(void);
+#else
+ #define sqlite3BeginBenignMalloc()
+ #define sqlite3EndBenignMalloc()
+#endif
+
+#define IN_INDEX_ROWID 1
+#define IN_INDEX_EPH 2
+#define IN_INDEX_INDEX_ASC 3
+#define IN_INDEX_INDEX_DESC 4
+SQLITE_PRIVATE int sqlite3FindInIndex(Parse *, Expr *, int*);
+
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+SQLITE_PRIVATE int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
+SQLITE_PRIVATE int sqlite3JournalSize(sqlite3_vfs *);
+SQLITE_PRIVATE int sqlite3JournalCreate(sqlite3_file *);
+SQLITE_PRIVATE int sqlite3JournalExists(sqlite3_file *p);
+#else
+ #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
+ #define sqlite3JournalExists(p) 1
+#endif
+
+SQLITE_PRIVATE void sqlite3MemJournalOpen(sqlite3_file *);
+SQLITE_PRIVATE int sqlite3MemJournalSize(void);
+SQLITE_PRIVATE int sqlite3IsMemJournal(sqlite3_file *);
+
+#if SQLITE_MAX_EXPR_DEPTH>0
+SQLITE_PRIVATE void sqlite3ExprSetHeight(Parse *pParse, Expr *p);
+SQLITE_PRIVATE int sqlite3SelectExprHeight(Select *);
+SQLITE_PRIVATE int sqlite3ExprCheckHeight(Parse*, int);
+#else
+ #define sqlite3ExprSetHeight(x,y)
+ #define sqlite3SelectExprHeight(x) 0
+ #define sqlite3ExprCheckHeight(x,y)
+#endif
+
+SQLITE_PRIVATE u32 sqlite3Get4byte(const u8*);
+SQLITE_PRIVATE void sqlite3Put4byte(u8*, u32);
+
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+SQLITE_PRIVATE void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
+SQLITE_PRIVATE void sqlite3ConnectionUnlocked(sqlite3 *db);
+SQLITE_PRIVATE void sqlite3ConnectionClosed(sqlite3 *db);
+#else
+ #define sqlite3ConnectionBlocked(x,y)
+ #define sqlite3ConnectionUnlocked(x)
+ #define sqlite3ConnectionClosed(x)
+#endif
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3ParserTrace(FILE*, char *);
+#endif
+
+/*
+** If the SQLITE_ENABLE IOTRACE exists then the global variable
+** sqlite3IoTrace is a pointer to a printf-like routine used to
+** print I/O tracing messages.
+*/
+#ifdef SQLITE_ENABLE_IOTRACE
+# define IOTRACE(A) if( sqlite3IoTrace ){ sqlite3IoTrace A; }
+SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe*);
+SQLITE_PRIVATE void (*sqlite3IoTrace)(const char*,...);
+#else
+# define IOTRACE(A)
+# define sqlite3VdbeIOTraceSql(X)
+#endif
+
+/*
+** These routines are available for the mem2.c debugging memory allocator
+** only. They are used to verify that different "types" of memory
+** allocations are properly tracked by the system.
+**
+** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
+** the MEMTYPE_* macros defined below. The type must be a bitmask with
+** a single bit set.
+**
+** sqlite3MemdebugHasType() returns true if any of the bits in its second
+** argument match the type set by the previous sqlite3MemdebugSetType().
+** sqlite3MemdebugHasType() is intended for use inside assert() statements.
+**
+** sqlite3MemdebugNoType() returns true if none of the bits in its second
+** argument match the type set by the previous sqlite3MemdebugSetType().
+**
+** Perhaps the most important point is the difference between MEMTYPE_HEAP
+** and MEMTYPE_LOOKASIDE. If an allocation is MEMTYPE_LOOKASIDE, that means
+** it might have been allocated by lookaside, except the allocation was
+** too large or lookaside was already full. It is important to verify
+** that allocations that might have been satisfied by lookaside are not
+** passed back to non-lookaside free() routines. Asserts such as the
+** example above are placed on the non-lookaside free() routines to verify
+** this constraint.
+**
+** All of this is no-op for a production build. It only comes into
+** play when the SQLITE_MEMDEBUG compile-time option is used.
+*/
+#ifdef SQLITE_MEMDEBUG
+SQLITE_PRIVATE void sqlite3MemdebugSetType(void*,u8);
+SQLITE_PRIVATE int sqlite3MemdebugHasType(void*,u8);
+SQLITE_PRIVATE int sqlite3MemdebugNoType(void*,u8);
+#else
+# define sqlite3MemdebugSetType(X,Y) /* no-op */
+# define sqlite3MemdebugHasType(X,Y) 1
+# define sqlite3MemdebugNoType(X,Y) 1
+#endif
+#define MEMTYPE_HEAP 0x01 /* General heap allocations */
+#define MEMTYPE_LOOKASIDE 0x02 /* Might have been lookaside memory */
+#define MEMTYPE_SCRATCH 0x04 /* Scratch allocations */
+#define MEMTYPE_PCACHE 0x08 /* Page cache allocations */
+#define MEMTYPE_DB 0x10 /* Uses sqlite3DbMalloc, not sqlite_malloc */
+
+#endif /* _SQLITEINT_H_ */
+
+/************** End of sqliteInt.h *******************************************/
+/************** Begin file global.c ******************************************/
+/*
+** 2008 June 13
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains definitions of global variables and contants.
+*/
+
+/* An array to map all upper-case characters into their corresponding
+** lower-case character.
+**
+** SQLite only considers US-ASCII (or EBCDIC) characters. We do not
+** handle case conversions for the UTF character set since the tables
+** involved are nearly as big or bigger than SQLite itself.
+*/
+SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[] = {
+#ifdef SQLITE_ASCII
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
+ 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
+ 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
+ 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 97, 98, 99,100,101,102,103,
+ 104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,
+ 122, 91, 92, 93, 94, 95, 96, 97, 98, 99,100,101,102,103,104,105,106,107,
+ 108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,
+ 126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
+ 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,
+ 162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,
+ 180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,
+ 198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
+ 216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,
+ 234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,
+ 252,253,254,255
+#endif
+#ifdef SQLITE_EBCDIC
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 0x */
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, /* 1x */
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, /* 2x */
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, /* 3x */
+ 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, /* 4x */
+ 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, /* 5x */
+ 96, 97, 66, 67, 68, 69, 70, 71, 72, 73,106,107,108,109,110,111, /* 6x */
+ 112, 81, 82, 83, 84, 85, 86, 87, 88, 89,122,123,124,125,126,127, /* 7x */
+ 128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143, /* 8x */
+ 144,145,146,147,148,149,150,151,152,153,154,155,156,157,156,159, /* 9x */
+ 160,161,162,163,164,165,166,167,168,169,170,171,140,141,142,175, /* Ax */
+ 176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191, /* Bx */
+ 192,129,130,131,132,133,134,135,136,137,202,203,204,205,206,207, /* Cx */
+ 208,145,146,147,148,149,150,151,152,153,218,219,220,221,222,223, /* Dx */
+ 224,225,162,163,164,165,166,167,168,169,232,203,204,205,206,207, /* Ex */
+ 239,240,241,242,243,244,245,246,247,248,249,219,220,221,222,255, /* Fx */
+#endif
+};
+
+/*
+** The following 256 byte lookup table is used to support SQLites built-in
+** equivalents to the following standard library functions:
+**
+** isspace() 0x01
+** isalpha() 0x02
+** isdigit() 0x04
+** isalnum() 0x06
+** isxdigit() 0x08
+** toupper() 0x20
+** SQLite identifier character 0x40
+**
+** Bit 0x20 is set if the mapped character requires translation to upper
+** case. i.e. if the character is a lower-case ASCII character.
+** If x is a lower-case ASCII character, then its upper-case equivalent
+** is (x - 0x20). Therefore toupper() can be implemented as:
+**
+** (x & ~(map[x]&0x20))
+**
+** Standard function tolower() is implemented using the sqlite3UpperToLower[]
+** array. tolower() is used more often than toupper() by SQLite.
+**
+** Bit 0x40 is set if the character non-alphanumeric and can be used in an
+** SQLite identifier. Identifiers are alphanumerics, "_", "$", and any
+** non-ASCII UTF character. Hence the test for whether or not a character is
+** part of an identifier is 0x46.
+**
+** SQLite's versions are identical to the standard versions assuming a
+** locale of "C". They are implemented as macros in sqliteInt.h.
+*/
+#ifdef SQLITE_ASCII
+SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[256] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 00..07 ........ */
+ 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, /* 08..0f ........ */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 10..17 ........ */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 18..1f ........ */
+ 0x01, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00, 0x00, /* 20..27 !"#$%&' */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 28..2f ()*+,-./ */
+ 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, /* 30..37 01234567 */
+ 0x0c, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 38..3f 89:;<=>? */
+
+ 0x00, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x02, /* 40..47 @ABCDEFG */
+ 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, /* 48..4f HIJKLMNO */
+ 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, /* 50..57 PQRSTUVW */
+ 0x02, 0x02, 0x02, 0x00, 0x00, 0x00, 0x00, 0x40, /* 58..5f XYZ[\]^_ */
+ 0x00, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x22, /* 60..67 `abcdefg */
+ 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, /* 68..6f hijklmno */
+ 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, /* 70..77 pqrstuvw */
+ 0x22, 0x22, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00, /* 78..7f xyz{|}~. */
+
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 80..87 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 88..8f ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 90..97 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* 98..9f ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* a0..a7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* a8..af ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* b0..b7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* b8..bf ........ */
+
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* c0..c7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* c8..cf ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* d0..d7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* d8..df ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* e0..e7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* e8..ef ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, /* f0..f7 ........ */
+ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40 /* f8..ff ........ */
+};
+#endif
+
+#ifndef SQLITE_USE_URI
+# define SQLITE_USE_URI 0
+#endif
+
+#ifndef SQLITE_ALLOW_COVERING_INDEX_SCAN
+# define SQLITE_ALLOW_COVERING_INDEX_SCAN 1
+#endif
+
+/*
+** The following singleton contains the global configuration for
+** the SQLite library.
+*/
+SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config = {
+ SQLITE_DEFAULT_MEMSTATUS, /* bMemstat */
+ 1, /* bCoreMutex */
+ SQLITE_THREADSAFE==1, /* bFullMutex */
+ SQLITE_USE_URI, /* bOpenUri */
+ SQLITE_ALLOW_COVERING_INDEX_SCAN, /* bUseCis */
+ 0x7ffffffe, /* mxStrlen */
+ 0, /* neverCorrupt */
+ 128, /* szLookaside */
+ 500, /* nLookaside */
+ {0,0,0,0,0,0,0,0}, /* m */
+ {0,0,0,0,0,0,0,0,0}, /* mutex */
+ {0,0,0,0,0,0,0,0,0,0,0,0,0},/* pcache2 */
+ (void*)0, /* pHeap */
+ 0, /* nHeap */
+ 0, 0, /* mnHeap, mxHeap */
+ SQLITE_DEFAULT_MMAP_SIZE, /* szMmap */
+ SQLITE_MAX_MMAP_SIZE, /* mxMmap */
+ (void*)0, /* pScratch */
+ 0, /* szScratch */
+ 0, /* nScratch */
+ (void*)0, /* pPage */
+ 0, /* szPage */
+ 0, /* nPage */
+ 0, /* mxParserStack */
+ 0, /* sharedCacheEnabled */
+ /* All the rest should always be initialized to zero */
+ 0, /* isInit */
+ 0, /* inProgress */
+ 0, /* isMutexInit */
+ 0, /* isMallocInit */
+ 0, /* isPCacheInit */
+ 0, /* nRefInitMutex */
+ 0, /* pInitMutex */
+ 0, /* xLog */
+ 0, /* pLogArg */
+#ifdef SQLITE_ENABLE_SQLLOG
+ 0, /* xSqllog */
+ 0, /* pSqllogArg */
+#endif
+#ifdef SQLITE_VDBE_COVERAGE
+ 0, /* xVdbeBranch */
+ 0, /* pVbeBranchArg */
+#endif
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+ 0, /* xTestCallback */
+#endif
+ 0 /* bLocaltimeFault */
+};
+
+/*
+** Hash table for global functions - functions common to all
+** database connections. After initialization, this table is
+** read-only.
+*/
+SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
+
+/*
+** Constant tokens for values 0 and 1.
+*/
+SQLITE_PRIVATE const Token sqlite3IntTokens[] = {
+ { "0", 1 },
+ { "1", 1 }
+};
+
+
+/*
+** The value of the "pending" byte must be 0x40000000 (1 byte past the
+** 1-gibabyte boundary) in a compatible database. SQLite never uses
+** the database page that contains the pending byte. It never attempts
+** to read or write that page. The pending byte page is set assign
+** for use by the VFS layers as space for managing file locks.
+**
+** During testing, it is often desirable to move the pending byte to
+** a different position in the file. This allows code that has to
+** deal with the pending byte to run on files that are much smaller
+** than 1 GiB. The sqlite3_test_control() interface can be used to
+** move the pending byte.
+**
+** IMPORTANT: Changing the pending byte to any value other than
+** 0x40000000 results in an incompatible database file format!
+** Changing the pending byte during operating results in undefined
+** and dileterious behavior.
+*/
+#ifndef SQLITE_OMIT_WSD
+SQLITE_PRIVATE int sqlite3PendingByte = 0x40000000;
+#endif
+
+/*
+** Properties of opcodes. The OPFLG_INITIALIZER macro is
+** created by mkopcodeh.awk during compilation. Data is obtained
+** from the comments following the "case OP_xxxx:" statements in
+** the vdbe.c file.
+*/
+SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[] = OPFLG_INITIALIZER;
+
+/************** End of global.c **********************************************/
+/************** Begin file ctime.c *******************************************/
+/*
+** 2010 February 23
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements routines used to report what compile-time options
+** SQLite was built with.
+*/
+
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+
+
+/*
+** An array of names of all compile-time options. This array should
+** be sorted A-Z.
+**
+** This array looks large, but in a typical installation actually uses
+** only a handful of compile-time options, so most times this array is usually
+** rather short and uses little memory space.
+*/
+static const char * const azCompileOpt[] = {
+
+/* These macros are provided to "stringify" the value of the define
+** for those options in which the value is meaningful. */
+#define CTIMEOPT_VAL_(opt) #opt
+#define CTIMEOPT_VAL(opt) CTIMEOPT_VAL_(opt)
+
+#ifdef SQLITE_32BIT_ROWID
+ "32BIT_ROWID",
+#endif
+#ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
+ "4_BYTE_ALIGNED_MALLOC",
+#endif
+#ifdef SQLITE_CASE_SENSITIVE_LIKE
+ "CASE_SENSITIVE_LIKE",
+#endif
+#ifdef SQLITE_CHECK_PAGES
+ "CHECK_PAGES",
+#endif
+#ifdef SQLITE_COVERAGE_TEST
+ "COVERAGE_TEST",
+#endif
+#ifdef SQLITE_DEBUG
+ "DEBUG",
+#endif
+#ifdef SQLITE_DEFAULT_LOCKING_MODE
+ "DEFAULT_LOCKING_MODE=" CTIMEOPT_VAL(SQLITE_DEFAULT_LOCKING_MODE),
+#endif
+#if defined(SQLITE_DEFAULT_MMAP_SIZE) && !defined(SQLITE_DEFAULT_MMAP_SIZE_xc)
+ "DEFAULT_MMAP_SIZE=" CTIMEOPT_VAL(SQLITE_DEFAULT_MMAP_SIZE),
+#endif
+#ifdef SQLITE_DISABLE_DIRSYNC
+ "DISABLE_DIRSYNC",
+#endif
+#ifdef SQLITE_DISABLE_LFS
+ "DISABLE_LFS",
+#endif
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+ "ENABLE_ATOMIC_WRITE",
+#endif
+#ifdef SQLITE_ENABLE_CEROD
+ "ENABLE_CEROD",
+#endif
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+ "ENABLE_COLUMN_METADATA",
+#endif
+#ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT
+ "ENABLE_EXPENSIVE_ASSERT",
+#endif
+#ifdef SQLITE_ENABLE_FTS1
+ "ENABLE_FTS1",
+#endif
+#ifdef SQLITE_ENABLE_FTS2
+ "ENABLE_FTS2",
+#endif
+#ifdef SQLITE_ENABLE_FTS3
+ "ENABLE_FTS3",
+#endif
+#ifdef SQLITE_ENABLE_FTS3_PARENTHESIS
+ "ENABLE_FTS3_PARENTHESIS",
+#endif
+#ifdef SQLITE_ENABLE_FTS4
+ "ENABLE_FTS4",
+#endif
+#ifdef SQLITE_ENABLE_ICU
+ "ENABLE_ICU",
+#endif
+#ifdef SQLITE_ENABLE_IOTRACE
+ "ENABLE_IOTRACE",
+#endif
+#ifdef SQLITE_ENABLE_LOAD_EXTENSION
+ "ENABLE_LOAD_EXTENSION",
+#endif
+#ifdef SQLITE_ENABLE_LOCKING_STYLE
+ "ENABLE_LOCKING_STYLE=" CTIMEOPT_VAL(SQLITE_ENABLE_LOCKING_STYLE),
+#endif
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+ "ENABLE_MEMORY_MANAGEMENT",
+#endif
+#ifdef SQLITE_ENABLE_MEMSYS3
+ "ENABLE_MEMSYS3",
+#endif
+#ifdef SQLITE_ENABLE_MEMSYS5
+ "ENABLE_MEMSYS5",
+#endif
+#ifdef SQLITE_ENABLE_OVERSIZE_CELL_CHECK
+ "ENABLE_OVERSIZE_CELL_CHECK",
+#endif
+#ifdef SQLITE_ENABLE_RTREE
+ "ENABLE_RTREE",
+#endif
+#if defined(SQLITE_ENABLE_STAT4)
+ "ENABLE_STAT4",
+#elif defined(SQLITE_ENABLE_STAT3)
+ "ENABLE_STAT3",
+#endif
+#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
+ "ENABLE_UNLOCK_NOTIFY",
+#endif
+#ifdef SQLITE_ENABLE_UPDATE_DELETE_LIMIT
+ "ENABLE_UPDATE_DELETE_LIMIT",
+#endif
+#ifdef SQLITE_HAS_CODEC
+ "HAS_CODEC",
+#endif
+#ifdef SQLITE_HAVE_ISNAN
+ "HAVE_ISNAN",
+#endif
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ "HOMEGROWN_RECURSIVE_MUTEX",
+#endif
+#ifdef SQLITE_IGNORE_AFP_LOCK_ERRORS
+ "IGNORE_AFP_LOCK_ERRORS",
+#endif
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+ "IGNORE_FLOCK_LOCK_ERRORS",
+#endif
+#ifdef SQLITE_INT64_TYPE
+ "INT64_TYPE",
+#endif
+#ifdef SQLITE_LOCK_TRACE
+ "LOCK_TRACE",
+#endif
+#if defined(SQLITE_MAX_MMAP_SIZE) && !defined(SQLITE_MAX_MMAP_SIZE_xc)
+ "MAX_MMAP_SIZE=" CTIMEOPT_VAL(SQLITE_MAX_MMAP_SIZE),
+#endif
+#ifdef SQLITE_MAX_SCHEMA_RETRY
+ "MAX_SCHEMA_RETRY=" CTIMEOPT_VAL(SQLITE_MAX_SCHEMA_RETRY),
+#endif
+#ifdef SQLITE_MEMDEBUG
+ "MEMDEBUG",
+#endif
+#ifdef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
+ "MIXED_ENDIAN_64BIT_FLOAT",
+#endif
+#ifdef SQLITE_NO_SYNC
+ "NO_SYNC",
+#endif
+#ifdef SQLITE_OMIT_ALTERTABLE
+ "OMIT_ALTERTABLE",
+#endif
+#ifdef SQLITE_OMIT_ANALYZE
+ "OMIT_ANALYZE",
+#endif
+#ifdef SQLITE_OMIT_ATTACH
+ "OMIT_ATTACH",
+#endif
+#ifdef SQLITE_OMIT_AUTHORIZATION
+ "OMIT_AUTHORIZATION",
+#endif
+#ifdef SQLITE_OMIT_AUTOINCREMENT
+ "OMIT_AUTOINCREMENT",
+#endif
+#ifdef SQLITE_OMIT_AUTOINIT
+ "OMIT_AUTOINIT",
+#endif
+#ifdef SQLITE_OMIT_AUTOMATIC_INDEX
+ "OMIT_AUTOMATIC_INDEX",
+#endif
+#ifdef SQLITE_OMIT_AUTORESET
+ "OMIT_AUTORESET",
+#endif
+#ifdef SQLITE_OMIT_AUTOVACUUM
+ "OMIT_AUTOVACUUM",
+#endif
+#ifdef SQLITE_OMIT_BETWEEN_OPTIMIZATION
+ "OMIT_BETWEEN_OPTIMIZATION",
+#endif
+#ifdef SQLITE_OMIT_BLOB_LITERAL
+ "OMIT_BLOB_LITERAL",
+#endif
+#ifdef SQLITE_OMIT_BTREECOUNT
+ "OMIT_BTREECOUNT",
+#endif
+#ifdef SQLITE_OMIT_BUILTIN_TEST
+ "OMIT_BUILTIN_TEST",
+#endif
+#ifdef SQLITE_OMIT_CAST
+ "OMIT_CAST",
+#endif
+#ifdef SQLITE_OMIT_CHECK
+ "OMIT_CHECK",
+#endif
+#ifdef SQLITE_OMIT_COMPLETE
+ "OMIT_COMPLETE",
+#endif
+#ifdef SQLITE_OMIT_COMPOUND_SELECT
+ "OMIT_COMPOUND_SELECT",
+#endif
+#ifdef SQLITE_OMIT_CTE
+ "OMIT_CTE",
+#endif
+#ifdef SQLITE_OMIT_DATETIME_FUNCS
+ "OMIT_DATETIME_FUNCS",
+#endif
+#ifdef SQLITE_OMIT_DECLTYPE
+ "OMIT_DECLTYPE",
+#endif
+#ifdef SQLITE_OMIT_DEPRECATED
+ "OMIT_DEPRECATED",
+#endif
+#ifdef SQLITE_OMIT_DISKIO
+ "OMIT_DISKIO",
+#endif
+#ifdef SQLITE_OMIT_EXPLAIN
+ "OMIT_EXPLAIN",
+#endif
+#ifdef SQLITE_OMIT_FLAG_PRAGMAS
+ "OMIT_FLAG_PRAGMAS",
+#endif
+#ifdef SQLITE_OMIT_FLOATING_POINT
+ "OMIT_FLOATING_POINT",
+#endif
+#ifdef SQLITE_OMIT_FOREIGN_KEY
+ "OMIT_FOREIGN_KEY",
+#endif
+#ifdef SQLITE_OMIT_GET_TABLE
+ "OMIT_GET_TABLE",
+#endif
+#ifdef SQLITE_OMIT_INCRBLOB
+ "OMIT_INCRBLOB",
+#endif
+#ifdef SQLITE_OMIT_INTEGRITY_CHECK
+ "OMIT_INTEGRITY_CHECK",
+#endif
+#ifdef SQLITE_OMIT_LIKE_OPTIMIZATION
+ "OMIT_LIKE_OPTIMIZATION",
+#endif
+#ifdef SQLITE_OMIT_LOAD_EXTENSION
+ "OMIT_LOAD_EXTENSION",
+#endif
+#ifdef SQLITE_OMIT_LOCALTIME
+ "OMIT_LOCALTIME",
+#endif
+#ifdef SQLITE_OMIT_LOOKASIDE
+ "OMIT_LOOKASIDE",
+#endif
+#ifdef SQLITE_OMIT_MEMORYDB
+ "OMIT_MEMORYDB",
+#endif
+#ifdef SQLITE_OMIT_OR_OPTIMIZATION
+ "OMIT_OR_OPTIMIZATION",
+#endif
+#ifdef SQLITE_OMIT_PAGER_PRAGMAS
+ "OMIT_PAGER_PRAGMAS",
+#endif
+#ifdef SQLITE_OMIT_PRAGMA
+ "OMIT_PRAGMA",
+#endif
+#ifdef SQLITE_OMIT_PROGRESS_CALLBACK
+ "OMIT_PROGRESS_CALLBACK",
+#endif
+#ifdef SQLITE_OMIT_QUICKBALANCE
+ "OMIT_QUICKBALANCE",
+#endif
+#ifdef SQLITE_OMIT_REINDEX
+ "OMIT_REINDEX",
+#endif
+#ifdef SQLITE_OMIT_SCHEMA_PRAGMAS
+ "OMIT_SCHEMA_PRAGMAS",
+#endif
+#ifdef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
+ "OMIT_SCHEMA_VERSION_PRAGMAS",
+#endif
+#ifdef SQLITE_OMIT_SHARED_CACHE
+ "OMIT_SHARED_CACHE",
+#endif
+#ifdef SQLITE_OMIT_SUBQUERY
+ "OMIT_SUBQUERY",
+#endif
+#ifdef SQLITE_OMIT_TCL_VARIABLE
+ "OMIT_TCL_VARIABLE",
+#endif
+#ifdef SQLITE_OMIT_TEMPDB
+ "OMIT_TEMPDB",
+#endif
+#ifdef SQLITE_OMIT_TRACE
+ "OMIT_TRACE",
+#endif
+#ifdef SQLITE_OMIT_TRIGGER
+ "OMIT_TRIGGER",
+#endif
+#ifdef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
+ "OMIT_TRUNCATE_OPTIMIZATION",
+#endif
+#ifdef SQLITE_OMIT_UTF16
+ "OMIT_UTF16",
+#endif
+#ifdef SQLITE_OMIT_VACUUM
+ "OMIT_VACUUM",
+#endif
+#ifdef SQLITE_OMIT_VIEW
+ "OMIT_VIEW",
+#endif
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+ "OMIT_VIRTUALTABLE",
+#endif
+#ifdef SQLITE_OMIT_WAL
+ "OMIT_WAL",
+#endif
+#ifdef SQLITE_OMIT_WSD
+ "OMIT_WSD",
+#endif
+#ifdef SQLITE_OMIT_XFER_OPT
+ "OMIT_XFER_OPT",
+#endif
+#ifdef SQLITE_PERFORMANCE_TRACE
+ "PERFORMANCE_TRACE",
+#endif
+#ifdef SQLITE_PROXY_DEBUG
+ "PROXY_DEBUG",
+#endif
+#ifdef SQLITE_RTREE_INT_ONLY
+ "RTREE_INT_ONLY",
+#endif
+#ifdef SQLITE_SECURE_DELETE
+ "SECURE_DELETE",
+#endif
+#ifdef SQLITE_SMALL_STACK
+ "SMALL_STACK",
+#endif
+#ifdef SQLITE_SOUNDEX
+ "SOUNDEX",
+#endif
+#ifdef SQLITE_SYSTEM_MALLOC
+ "SYSTEM_MALLOC",
+#endif
+#ifdef SQLITE_TCL
+ "TCL",
+#endif
+#if defined(SQLITE_TEMP_STORE) && !defined(SQLITE_TEMP_STORE_xc)
+ "TEMP_STORE=" CTIMEOPT_VAL(SQLITE_TEMP_STORE),
+#endif
+#ifdef SQLITE_TEST
+ "TEST",
+#endif
+#if defined(SQLITE_THREADSAFE)
+ "THREADSAFE=" CTIMEOPT_VAL(SQLITE_THREADSAFE),
+#endif
+#ifdef SQLITE_USE_ALLOCA
+ "USE_ALLOCA",
+#endif
+#ifdef SQLITE_WIN32_MALLOC
+ "WIN32_MALLOC",
+#endif
+#ifdef SQLITE_ZERO_MALLOC
+ "ZERO_MALLOC"
+#endif
+};
+
+/*
+** Given the name of a compile-time option, return true if that option
+** was used and false if not.
+**
+** The name can optionally begin with "SQLITE_" but the "SQLITE_" prefix
+** is not required for a match.
+*/
+SQLITE_API int sqlite3_compileoption_used(const char *zOptName){
+ int i, n;
+ if( sqlite3StrNICmp(zOptName, "SQLITE_", 7)==0 ) zOptName += 7;
+ n = sqlite3Strlen30(zOptName);
+
+ /* Since ArraySize(azCompileOpt) is normally in single digits, a
+ ** linear search is adequate. No need for a binary search. */
+ for(i=0; i=0 && NaDb[] (or -1) */
+ u8 nullRow; /* True if pointing to a row with no data */
+ u8 rowidIsValid; /* True if lastRowid is valid */
+ u8 deferredMoveto; /* A call to sqlite3BtreeMoveto() is needed */
+ Bool isEphemeral:1; /* True for an ephemeral table */
+ Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */
+ Bool isTable:1; /* True if a table requiring integer keys */
+ Bool isOrdered:1; /* True if the underlying table is BTREE_UNORDERED */
+ sqlite3_vtab_cursor *pVtabCursor; /* The cursor for a virtual table */
+ i64 seqCount; /* Sequence counter */
+ i64 movetoTarget; /* Argument to the deferred sqlite3BtreeMoveto() */
+ i64 lastRowid; /* Rowid being deleted by OP_Delete */
+ VdbeSorter *pSorter; /* Sorter object for OP_SorterOpen cursors */
+
+ /* Cached information about the header for the data record that the
+ ** cursor is currently pointing to. Only valid if cacheStatus matches
+ ** Vdbe.cacheCtr. Vdbe.cacheCtr will never take on the value of
+ ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
+ ** the cache is out of date.
+ **
+ ** aRow might point to (ephemeral) data for the current row, or it might
+ ** be NULL.
+ */
+ u32 cacheStatus; /* Cache is valid if this matches Vdbe.cacheCtr */
+ u32 payloadSize; /* Total number of bytes in the record */
+ u32 szRow; /* Byte available in aRow */
+ u32 iHdrOffset; /* Offset to next unparsed byte of the header */
+ const u8 *aRow; /* Data for the current row, if all on one page */
+ u32 aType[1]; /* Type values for all entries in the record */
+ /* 2*nField extra array elements allocated for aType[], beyond the one
+ ** static element declared in the structure. nField total array slots for
+ ** aType[] and nField+1 array slots for aOffset[] */
+};
+typedef struct VdbeCursor VdbeCursor;
+
+/*
+** When a sub-program is executed (OP_Program), a structure of this type
+** is allocated to store the current value of the program counter, as
+** well as the current memory cell array and various other frame specific
+** values stored in the Vdbe struct. When the sub-program is finished,
+** these values are copied back to the Vdbe from the VdbeFrame structure,
+** restoring the state of the VM to as it was before the sub-program
+** began executing.
+**
+** The memory for a VdbeFrame object is allocated and managed by a memory
+** cell in the parent (calling) frame. When the memory cell is deleted or
+** overwritten, the VdbeFrame object is not freed immediately. Instead, it
+** is linked into the Vdbe.pDelFrame list. The contents of the Vdbe.pDelFrame
+** list is deleted when the VM is reset in VdbeHalt(). The reason for doing
+** this instead of deleting the VdbeFrame immediately is to avoid recursive
+** calls to sqlite3VdbeMemRelease() when the memory cells belonging to the
+** child frame are released.
+**
+** The currently executing frame is stored in Vdbe.pFrame. Vdbe.pFrame is
+** set to NULL if the currently executing frame is the main program.
+*/
+typedef struct VdbeFrame VdbeFrame;
+struct VdbeFrame {
+ Vdbe *v; /* VM this frame belongs to */
+ VdbeFrame *pParent; /* Parent of this frame, or NULL if parent is main */
+ Op *aOp; /* Program instructions for parent frame */
+ Mem *aMem; /* Array of memory cells for parent frame */
+ u8 *aOnceFlag; /* Array of OP_Once flags for parent frame */
+ VdbeCursor **apCsr; /* Array of Vdbe cursors for parent frame */
+ void *token; /* Copy of SubProgram.token */
+ i64 lastRowid; /* Last insert rowid (sqlite3.lastRowid) */
+ int nCursor; /* Number of entries in apCsr */
+ int pc; /* Program Counter in parent (calling) frame */
+ int nOp; /* Size of aOp array */
+ int nMem; /* Number of entries in aMem */
+ int nOnceFlag; /* Number of entries in aOnceFlag */
+ int nChildMem; /* Number of memory cells for child frame */
+ int nChildCsr; /* Number of cursors for child frame */
+ int nChange; /* Statement changes (Vdbe.nChanges) */
+};
+
+#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
+
+/*
+** A value for VdbeCursor.cacheValid that means the cache is always invalid.
+*/
+#define CACHE_STALE 0
+
+/*
+** Internally, the vdbe manipulates nearly all SQL values as Mem
+** structures. Each Mem struct may cache multiple representations (string,
+** integer etc.) of the same value.
+*/
+struct Mem {
+ sqlite3 *db; /* The associated database connection */
+ char *z; /* String or BLOB value */
+ double r; /* Real value */
+ union {
+ i64 i; /* Integer value used when MEM_Int is set in flags */
+ int nZero; /* Used when bit MEM_Zero is set in flags */
+ FuncDef *pDef; /* Used only when flags==MEM_Agg */
+ RowSet *pRowSet; /* Used only when flags==MEM_RowSet */
+ VdbeFrame *pFrame; /* Used when flags==MEM_Frame */
+ } u;
+ int n; /* Number of characters in string value, excluding '\0' */
+ u16 flags; /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
+ u8 enc; /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
+#ifdef SQLITE_DEBUG
+ Mem *pScopyFrom; /* This Mem is a shallow copy of pScopyFrom */
+ void *pFiller; /* So that sizeof(Mem) is a multiple of 8 */
+#endif
+ void (*xDel)(void *); /* If not null, call this function to delete Mem.z */
+ char *zMalloc; /* Dynamic buffer allocated by sqlite3_malloc() */
+};
+
+/* One or more of the following flags are set to indicate the validOK
+** representations of the value stored in the Mem struct.
+**
+** If the MEM_Null flag is set, then the value is an SQL NULL value.
+** No other flags may be set in this case.
+**
+** If the MEM_Str flag is set then Mem.z points at a string representation.
+** Usually this is encoded in the same unicode encoding as the main
+** database (see below for exceptions). If the MEM_Term flag is also
+** set, then the string is nul terminated. The MEM_Int and MEM_Real
+** flags may coexist with the MEM_Str flag.
+*/
+#define MEM_Null 0x0001 /* Value is NULL */
+#define MEM_Str 0x0002 /* Value is a string */
+#define MEM_Int 0x0004 /* Value is an integer */
+#define MEM_Real 0x0008 /* Value is a real number */
+#define MEM_Blob 0x0010 /* Value is a BLOB */
+#define MEM_AffMask 0x001f /* Mask of affinity bits */
+#define MEM_RowSet 0x0020 /* Value is a RowSet object */
+#define MEM_Frame 0x0040 /* Value is a VdbeFrame object */
+#define MEM_Undefined 0x0080 /* Value is undefined */
+#define MEM_Cleared 0x0100 /* NULL set by OP_Null, not from data */
+#define MEM_TypeMask 0x01ff /* Mask of type bits */
+
+
+/* Whenever Mem contains a valid string or blob representation, one of
+** the following flags must be set to determine the memory management
+** policy for Mem.z. The MEM_Term flag tells us whether or not the
+** string is \000 or \u0000 terminated
+*/
+#define MEM_Term 0x0200 /* String rep is nul terminated */
+#define MEM_Dyn 0x0400 /* Need to call Mem.xDel() on Mem.z */
+#define MEM_Static 0x0800 /* Mem.z points to a static string */
+#define MEM_Ephem 0x1000 /* Mem.z points to an ephemeral string */
+#define MEM_Agg 0x2000 /* Mem.z points to an agg function context */
+#define MEM_Zero 0x4000 /* Mem.i contains count of 0s appended to blob */
+#ifdef SQLITE_OMIT_INCRBLOB
+ #undef MEM_Zero
+ #define MEM_Zero 0x0000
+#endif
+
+/*
+** Clear any existing type flags from a Mem and replace them with f
+*/
+#define MemSetTypeFlag(p, f) \
+ ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
+
+/*
+** Return true if a memory cell is not marked as invalid. This macro
+** is for use inside assert() statements only.
+*/
+#ifdef SQLITE_DEBUG
+#define memIsValid(M) ((M)->flags & MEM_Undefined)==0
+#endif
+
+/*
+** Each auxilliary data pointer stored by a user defined function
+** implementation calling sqlite3_set_auxdata() is stored in an instance
+** of this structure. All such structures associated with a single VM
+** are stored in a linked list headed at Vdbe.pAuxData. All are destroyed
+** when the VM is halted (if not before).
+*/
+struct AuxData {
+ int iOp; /* Instruction number of OP_Function opcode */
+ int iArg; /* Index of function argument. */
+ void *pAux; /* Aux data pointer */
+ void (*xDelete)(void *); /* Destructor for the aux data */
+ AuxData *pNext; /* Next element in list */
+};
+
+/*
+** The "context" argument for a installable function. A pointer to an
+** instance of this structure is the first argument to the routines used
+** implement the SQL functions.
+**
+** There is a typedef for this structure in sqlite.h. So all routines,
+** even the public interface to SQLite, can use a pointer to this structure.
+** But this file is the only place where the internal details of this
+** structure are known.
+**
+** This structure is defined inside of vdbeInt.h because it uses substructures
+** (Mem) which are only defined there.
+*/
+struct sqlite3_context {
+ FuncDef *pFunc; /* Pointer to function information. MUST BE FIRST */
+ Mem s; /* The return value is stored here */
+ Mem *pMem; /* Memory cell used to store aggregate context */
+ CollSeq *pColl; /* Collating sequence */
+ Vdbe *pVdbe; /* The VM that owns this context */
+ int iOp; /* Instruction number of OP_Function */
+ int isError; /* Error code returned by the function. */
+ u8 skipFlag; /* Skip skip accumulator loading if true */
+ u8 fErrorOrAux; /* isError!=0 or pVdbe->pAuxData modified */
+};
+
+/*
+** An Explain object accumulates indented output which is helpful
+** in describing recursive data structures.
+*/
+struct Explain {
+ Vdbe *pVdbe; /* Attach the explanation to this Vdbe */
+ StrAccum str; /* The string being accumulated */
+ int nIndent; /* Number of elements in aIndent */
+ u16 aIndent[100]; /* Levels of indentation */
+ char zBase[100]; /* Initial space */
+};
+
+/* A bitfield type for use inside of structures. Always follow with :N where
+** N is the number of bits.
+*/
+typedef unsigned bft; /* Bit Field Type */
+
+/*
+** An instance of the virtual machine. This structure contains the complete
+** state of the virtual machine.
+**
+** The "sqlite3_stmt" structure pointer that is returned by sqlite3_prepare()
+** is really a pointer to an instance of this structure.
+**
+** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
+** any virtual table method invocations made by the vdbe program. It is
+** set to 2 for xDestroy method calls and 1 for all other methods. This
+** variable is used for two purposes: to allow xDestroy methods to execute
+** "DROP TABLE" statements and to prevent some nasty side effects of
+** malloc failure when SQLite is invoked recursively by a virtual table
+** method function.
+*/
+struct Vdbe {
+ sqlite3 *db; /* The database connection that owns this statement */
+ Op *aOp; /* Space to hold the virtual machine's program */
+ Mem *aMem; /* The memory locations */
+ Mem **apArg; /* Arguments to currently executing user function */
+ Mem *aColName; /* Column names to return */
+ Mem *pResultSet; /* Pointer to an array of results */
+ Parse *pParse; /* Parsing context used to create this Vdbe */
+ int nMem; /* Number of memory locations currently allocated */
+ int nOp; /* Number of instructions in the program */
+ int nCursor; /* Number of slots in apCsr[] */
+ u32 magic; /* Magic number for sanity checking */
+ char *zErrMsg; /* Error message written here */
+ Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */
+ VdbeCursor **apCsr; /* One element of this array for each open cursor */
+ Mem *aVar; /* Values for the OP_Variable opcode. */
+ char **azVar; /* Name of variables */
+ ynVar nVar; /* Number of entries in aVar[] */
+ ynVar nzVar; /* Number of entries in azVar[] */
+ u32 cacheCtr; /* VdbeCursor row cache generation counter */
+ int pc; /* The program counter */
+ int rc; /* Value to return */
+ u16 nResColumn; /* Number of columns in one row of the result set */
+ u8 errorAction; /* Recovery action to do in case of an error */
+ u8 minWriteFileFormat; /* Minimum file format for writable database files */
+ bft explain:2; /* True if EXPLAIN present on SQL command */
+ bft inVtabMethod:2; /* See comments above */
+ bft changeCntOn:1; /* True to update the change-counter */
+ bft expired:1; /* True if the VM needs to be recompiled */
+ bft runOnlyOnce:1; /* Automatically expire on reset */
+ bft usesStmtJournal:1; /* True if uses a statement journal */
+ bft readOnly:1; /* True for statements that do not write */
+ bft bIsReader:1; /* True for statements that read */
+ bft isPrepareV2:1; /* True if prepared with prepare_v2() */
+ bft doingRerun:1; /* True if rerunning after an auto-reprepare */
+ int nChange; /* Number of db changes made since last reset */
+ yDbMask btreeMask; /* Bitmask of db->aDb[] entries referenced */
+ yDbMask lockMask; /* Subset of btreeMask that requires a lock */
+ int iStatement; /* Statement number (or 0 if has not opened stmt) */
+ u32 aCounter[5]; /* Counters used by sqlite3_stmt_status() */
+#ifndef SQLITE_OMIT_TRACE
+ i64 startTime; /* Time when query started - used for profiling */
+#endif
+ i64 iCurrentTime; /* Value of julianday('now') for this statement */
+ i64 nFkConstraint; /* Number of imm. FK constraints this VM */
+ i64 nStmtDefCons; /* Number of def. constraints when stmt started */
+ i64 nStmtDefImmCons; /* Number of def. imm constraints when stmt started */
+ char *zSql; /* Text of the SQL statement that generated this */
+ void *pFree; /* Free this when deleting the vdbe */
+#ifdef SQLITE_ENABLE_TREE_EXPLAIN
+ Explain *pExplain; /* The explainer */
+ char *zExplain; /* Explanation of data structures */
+#endif
+ VdbeFrame *pFrame; /* Parent frame */
+ VdbeFrame *pDelFrame; /* List of frame objects to free on VM reset */
+ int nFrame; /* Number of frames in pFrame list */
+ u32 expmask; /* Binding to these vars invalidates VM */
+ SubProgram *pProgram; /* Linked list of all sub-programs used by VM */
+ int nOnceFlag; /* Size of array aOnceFlag[] */
+ u8 *aOnceFlag; /* Flags for OP_Once */
+ AuxData *pAuxData; /* Linked list of auxdata allocations */
+};
+
+/*
+** The following are allowed values for Vdbe.magic
+*/
+#define VDBE_MAGIC_INIT 0x26bceaa5 /* Building a VDBE program */
+#define VDBE_MAGIC_RUN 0xbdf20da3 /* VDBE is ready to execute */
+#define VDBE_MAGIC_HALT 0x519c2973 /* VDBE has completed execution */
+#define VDBE_MAGIC_DEAD 0xb606c3c8 /* The VDBE has been deallocated */
+
+/*
+** Function prototypes
+*/
+SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
+void sqliteVdbePopStack(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor*);
+#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
+SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, Op*);
+#endif
+SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
+SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(Vdbe*, int, int);
+
+int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
+SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
+SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
+SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
+SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *, int);
+SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem*, const Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
+SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem*, Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
+SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem*, i64);
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
+#else
+SQLITE_PRIVATE void sqlite3VdbeMemSetDouble(Mem*, double);
+#endif
+SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem*,int);
+SQLITE_PRIVATE void sqlite3VdbeMemSetRowSet(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem*, int);
+SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
+SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
+SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p);
+#define VdbeMemDynamic(X) \
+ (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
+#define VdbeMemRelease(X) \
+ if( VdbeMemDynamic(X) ) sqlite3VdbeMemReleaseExternal(X);
+SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
+SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
+SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
+SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
+SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
+SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
+SQLITE_PRIVATE int sqlite3VdbeTransferError(Vdbe *p);
+
+SQLITE_PRIVATE int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
+SQLITE_PRIVATE void sqlite3VdbeSorterReset(sqlite3 *, VdbeSorter *);
+SQLITE_PRIVATE void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
+SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
+SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
+SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *, const VdbeCursor *, int *);
+SQLITE_PRIVATE int sqlite3VdbeSorterWrite(sqlite3 *, const VdbeCursor *, Mem *);
+SQLITE_PRIVATE int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int, int *);
+
+#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
+SQLITE_PRIVATE void sqlite3VdbeEnter(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeLeave(Vdbe*);
+#else
+# define sqlite3VdbeEnter(X)
+# define sqlite3VdbeLeave(X)
+#endif
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3VdbeMemAboutToChange(Vdbe*,Mem*);
+SQLITE_PRIVATE int sqlite3VdbeCheckMemInvariants(Mem*);
+#endif
+
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
+#else
+# define sqlite3VdbeCheckFk(p,i) 0
+#endif
+
+SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem*, u8);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3VdbePrintSql(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
+#endif
+SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem);
+
+#ifndef SQLITE_OMIT_INCRBLOB
+SQLITE_PRIVATE int sqlite3VdbeMemExpandBlob(Mem *);
+ #define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
+#else
+ #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
+ #define ExpandBlob(P) SQLITE_OK
+#endif
+
+#endif /* !defined(_VDBEINT_H_) */
+
+/************** End of vdbeInt.h *********************************************/
+/************** Continuing where we left off in status.c *********************/
+
+/*
+** Variables in which to record status information.
+*/
+typedef struct sqlite3StatType sqlite3StatType;
+static SQLITE_WSD struct sqlite3StatType {
+ int nowValue[10]; /* Current value */
+ int mxValue[10]; /* Maximum value */
+} sqlite3Stat = { {0,}, {0,} };
+
+
+/* The "wsdStat" macro will resolve to the status information
+** state vector. If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time. In the more common
+** case where writable static data is supported, wsdStat can refer directly
+** to the "sqlite3Stat" state vector declared above.
+*/
+#ifdef SQLITE_OMIT_WSD
+# define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat)
+# define wsdStat x[0]
+#else
+# define wsdStatInit
+# define wsdStat sqlite3Stat
+#endif
+
+/*
+** Return the current value of a status parameter.
+*/
+SQLITE_PRIVATE int sqlite3StatusValue(int op){
+ wsdStatInit;
+ assert( op>=0 && op=0 && opwsdStat.mxValue[op] ){
+ wsdStat.mxValue[op] = wsdStat.nowValue[op];
+ }
+}
+
+/*
+** Set the value of a status to X.
+*/
+SQLITE_PRIVATE void sqlite3StatusSet(int op, int X){
+ wsdStatInit;
+ assert( op>=0 && opwsdStat.mxValue[op] ){
+ wsdStat.mxValue[op] = wsdStat.nowValue[op];
+ }
+}
+
+/*
+** Query status information.
+**
+** This implementation assumes that reading or writing an aligned
+** 32-bit integer is an atomic operation. If that assumption is not true,
+** then this routine is not threadsafe.
+*/
+SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
+ wsdStatInit;
+ if( op<0 || op>=ArraySize(wsdStat.nowValue) ){
+ return SQLITE_MISUSE_BKPT;
+ }
+ *pCurrent = wsdStat.nowValue[op];
+ *pHighwater = wsdStat.mxValue[op];
+ if( resetFlag ){
+ wsdStat.mxValue[op] = wsdStat.nowValue[op];
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Query status information for a single database connection
+*/
+SQLITE_API int sqlite3_db_status(
+ sqlite3 *db, /* The database connection whose status is desired */
+ int op, /* Status verb */
+ int *pCurrent, /* Write current value here */
+ int *pHighwater, /* Write high-water mark here */
+ int resetFlag /* Reset high-water mark if true */
+){
+ int rc = SQLITE_OK; /* Return code */
+ sqlite3_mutex_enter(db->mutex);
+ switch( op ){
+ case SQLITE_DBSTATUS_LOOKASIDE_USED: {
+ *pCurrent = db->lookaside.nOut;
+ *pHighwater = db->lookaside.mxOut;
+ if( resetFlag ){
+ db->lookaside.mxOut = db->lookaside.nOut;
+ }
+ break;
+ }
+
+ case SQLITE_DBSTATUS_LOOKASIDE_HIT:
+ case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE:
+ case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: {
+ testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT );
+ testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE );
+ testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL );
+ assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 );
+ assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 );
+ *pCurrent = 0;
+ *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT];
+ if( resetFlag ){
+ db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0;
+ }
+ break;
+ }
+
+ /*
+ ** Return an approximation for the amount of memory currently used
+ ** by all pagers associated with the given database connection. The
+ ** highwater mark is meaningless and is returned as zero.
+ */
+ case SQLITE_DBSTATUS_CACHE_USED: {
+ int totalUsed = 0;
+ int i;
+ sqlite3BtreeEnterAll(db);
+ for(i=0; inDb; i++){
+ Btree *pBt = db->aDb[i].pBt;
+ if( pBt ){
+ Pager *pPager = sqlite3BtreePager(pBt);
+ totalUsed += sqlite3PagerMemUsed(pPager);
+ }
+ }
+ sqlite3BtreeLeaveAll(db);
+ *pCurrent = totalUsed;
+ *pHighwater = 0;
+ break;
+ }
+
+ /*
+ ** *pCurrent gets an accurate estimate of the amount of memory used
+ ** to store the schema for all databases (main, temp, and any ATTACHed
+ ** databases. *pHighwater is set to zero.
+ */
+ case SQLITE_DBSTATUS_SCHEMA_USED: {
+ int i; /* Used to iterate through schemas */
+ int nByte = 0; /* Used to accumulate return value */
+
+ sqlite3BtreeEnterAll(db);
+ db->pnBytesFreed = &nByte;
+ for(i=0; inDb; i++){
+ Schema *pSchema = db->aDb[i].pSchema;
+ if( ALWAYS(pSchema!=0) ){
+ HashElem *p;
+
+ nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
+ pSchema->tblHash.count
+ + pSchema->trigHash.count
+ + pSchema->idxHash.count
+ + pSchema->fkeyHash.count
+ );
+ nByte += sqlite3MallocSize(pSchema->tblHash.ht);
+ nByte += sqlite3MallocSize(pSchema->trigHash.ht);
+ nByte += sqlite3MallocSize(pSchema->idxHash.ht);
+ nByte += sqlite3MallocSize(pSchema->fkeyHash.ht);
+
+ for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
+ sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
+ }
+ for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
+ sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
+ }
+ }
+ }
+ db->pnBytesFreed = 0;
+ sqlite3BtreeLeaveAll(db);
+
+ *pHighwater = 0;
+ *pCurrent = nByte;
+ break;
+ }
+
+ /*
+ ** *pCurrent gets an accurate estimate of the amount of memory used
+ ** to store all prepared statements.
+ ** *pHighwater is set to zero.
+ */
+ case SQLITE_DBSTATUS_STMT_USED: {
+ struct Vdbe *pVdbe; /* Used to iterate through VMs */
+ int nByte = 0; /* Used to accumulate return value */
+
+ db->pnBytesFreed = &nByte;
+ for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
+ sqlite3VdbeClearObject(db, pVdbe);
+ sqlite3DbFree(db, pVdbe);
+ }
+ db->pnBytesFreed = 0;
+
+ *pHighwater = 0;
+ *pCurrent = nByte;
+
+ break;
+ }
+
+ /*
+ ** Set *pCurrent to the total cache hits or misses encountered by all
+ ** pagers the database handle is connected to. *pHighwater is always set
+ ** to zero.
+ */
+ case SQLITE_DBSTATUS_CACHE_HIT:
+ case SQLITE_DBSTATUS_CACHE_MISS:
+ case SQLITE_DBSTATUS_CACHE_WRITE:{
+ int i;
+ int nRet = 0;
+ assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 );
+ assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 );
+
+ for(i=0; inDb; i++){
+ if( db->aDb[i].pBt ){
+ Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt);
+ sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet);
+ }
+ }
+ *pHighwater = 0;
+ *pCurrent = nRet;
+ break;
+ }
+
+ /* Set *pCurrent to non-zero if there are unresolved deferred foreign
+ ** key constraints. Set *pCurrent to zero if all foreign key constraints
+ ** have been satisfied. The *pHighwater is always set to zero.
+ */
+ case SQLITE_DBSTATUS_DEFERRED_FKS: {
+ *pHighwater = 0;
+ *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
+ break;
+ }
+
+ default: {
+ rc = SQLITE_ERROR;
+ }
+ }
+ sqlite3_mutex_leave(db->mutex);
+ return rc;
+}
+
+/************** End of status.c **********************************************/
+/************** Begin file date.c ********************************************/
+/*
+** 2003 October 31
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement date and time
+** functions for SQLite.
+**
+** There is only one exported symbol in this file - the function
+** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
+** All other code has file scope.
+**
+** SQLite processes all times and dates as Julian Day numbers. The
+** dates and times are stored as the number of days since noon
+** in Greenwich on November 24, 4714 B.C. according to the Gregorian
+** calendar system.
+**
+** 1970-01-01 00:00:00 is JD 2440587.5
+** 2000-01-01 00:00:00 is JD 2451544.5
+**
+** This implemention requires years to be expressed as a 4-digit number
+** which means that only dates between 0000-01-01 and 9999-12-31 can
+** be represented, even though julian day numbers allow a much wider
+** range of dates.
+**
+** The Gregorian calendar system is used for all dates and times,
+** even those that predate the Gregorian calendar. Historians usually
+** use the Julian calendar for dates prior to 1582-10-15 and for some
+** dates afterwards, depending on locale. Beware of this difference.
+**
+** The conversion algorithms are implemented based on descriptions
+** in the following text:
+**
+** Jean Meeus
+** Astronomical Algorithms, 2nd Edition, 1998
+** ISBM 0-943396-61-1
+** Willmann-Bell, Inc
+** Richmond, Virginia (USA)
+*/
+/* #include */
+/* #include */
+#include
+
+#ifndef SQLITE_OMIT_DATETIME_FUNCS
+
+
+/*
+** A structure for holding a single date and time.
+*/
+typedef struct DateTime DateTime;
+struct DateTime {
+ sqlite3_int64 iJD; /* The julian day number times 86400000 */
+ int Y, M, D; /* Year, month, and day */
+ int h, m; /* Hour and minutes */
+ int tz; /* Timezone offset in minutes */
+ double s; /* Seconds */
+ char validYMD; /* True (1) if Y,M,D are valid */
+ char validHMS; /* True (1) if h,m,s are valid */
+ char validJD; /* True (1) if iJD is valid */
+ char validTZ; /* True (1) if tz is valid */
+};
+
+
+/*
+** Convert zDate into one or more integers. Additional arguments
+** come in groups of 5 as follows:
+**
+** N number of digits in the integer
+** min minimum allowed value of the integer
+** max maximum allowed value of the integer
+** nextC first character after the integer
+** pVal where to write the integers value.
+**
+** Conversions continue until one with nextC==0 is encountered.
+** The function returns the number of successful conversions.
+*/
+static int getDigits(const char *zDate, ...){
+ va_list ap;
+ int val;
+ int N;
+ int min;
+ int max;
+ int nextC;
+ int *pVal;
+ int cnt = 0;
+ va_start(ap, zDate);
+ do{
+ N = va_arg(ap, int);
+ min = va_arg(ap, int);
+ max = va_arg(ap, int);
+ nextC = va_arg(ap, int);
+ pVal = va_arg(ap, int*);
+ val = 0;
+ while( N-- ){
+ if( !sqlite3Isdigit(*zDate) ){
+ goto end_getDigits;
+ }
+ val = val*10 + *zDate - '0';
+ zDate++;
+ }
+ if( valmax || (nextC!=0 && nextC!=*zDate) ){
+ goto end_getDigits;
+ }
+ *pVal = val;
+ zDate++;
+ cnt++;
+ }while( nextC );
+end_getDigits:
+ va_end(ap);
+ return cnt;
+}
+
+/*
+** Parse a timezone extension on the end of a date-time.
+** The extension is of the form:
+**
+** (+/-)HH:MM
+**
+** Or the "zulu" notation:
+**
+** Z
+**
+** If the parse is successful, write the number of minutes
+** of change in p->tz and return 0. If a parser error occurs,
+** return non-zero.
+**
+** A missing specifier is not considered an error.
+*/
+static int parseTimezone(const char *zDate, DateTime *p){
+ int sgn = 0;
+ int nHr, nMn;
+ int c;
+ while( sqlite3Isspace(*zDate) ){ zDate++; }
+ p->tz = 0;
+ c = *zDate;
+ if( c=='-' ){
+ sgn = -1;
+ }else if( c=='+' ){
+ sgn = +1;
+ }else if( c=='Z' || c=='z' ){
+ zDate++;
+ goto zulu_time;
+ }else{
+ return c!=0;
+ }
+ zDate++;
+ if( getDigits(zDate, 2, 0, 14, ':', &nHr, 2, 0, 59, 0, &nMn)!=2 ){
+ return 1;
+ }
+ zDate += 5;
+ p->tz = sgn*(nMn + nHr*60);
+zulu_time:
+ while( sqlite3Isspace(*zDate) ){ zDate++; }
+ return *zDate!=0;
+}
+
+/*
+** Parse times of the form HH:MM or HH:MM:SS or HH:MM:SS.FFFF.
+** The HH, MM, and SS must each be exactly 2 digits. The
+** fractional seconds FFFF can be one or more digits.
+**
+** Return 1 if there is a parsing error and 0 on success.
+*/
+static int parseHhMmSs(const char *zDate, DateTime *p){
+ int h, m, s;
+ double ms = 0.0;
+ if( getDigits(zDate, 2, 0, 24, ':', &h, 2, 0, 59, 0, &m)!=2 ){
+ return 1;
+ }
+ zDate += 5;
+ if( *zDate==':' ){
+ zDate++;
+ if( getDigits(zDate, 2, 0, 59, 0, &s)!=1 ){
+ return 1;
+ }
+ zDate += 2;
+ if( *zDate=='.' && sqlite3Isdigit(zDate[1]) ){
+ double rScale = 1.0;
+ zDate++;
+ while( sqlite3Isdigit(*zDate) ){
+ ms = ms*10.0 + *zDate - '0';
+ rScale *= 10.0;
+ zDate++;
+ }
+ ms /= rScale;
+ }
+ }else{
+ s = 0;
+ }
+ p->validJD = 0;
+ p->validHMS = 1;
+ p->h = h;
+ p->m = m;
+ p->s = s + ms;
+ if( parseTimezone(zDate, p) ) return 1;
+ p->validTZ = (p->tz!=0)?1:0;
+ return 0;
+}
+
+/*
+** Convert from YYYY-MM-DD HH:MM:SS to julian day. We always assume
+** that the YYYY-MM-DD is according to the Gregorian calendar.
+**
+** Reference: Meeus page 61
+*/
+static void computeJD(DateTime *p){
+ int Y, M, D, A, B, X1, X2;
+
+ if( p->validJD ) return;
+ if( p->validYMD ){
+ Y = p->Y;
+ M = p->M;
+ D = p->D;
+ }else{
+ Y = 2000; /* If no YMD specified, assume 2000-Jan-01 */
+ M = 1;
+ D = 1;
+ }
+ if( M<=2 ){
+ Y--;
+ M += 12;
+ }
+ A = Y/100;
+ B = 2 - A + (A/4);
+ X1 = 36525*(Y+4716)/100;
+ X2 = 306001*(M+1)/10000;
+ p->iJD = (sqlite3_int64)((X1 + X2 + D + B - 1524.5 ) * 86400000);
+ p->validJD = 1;
+ if( p->validHMS ){
+ p->iJD += p->h*3600000 + p->m*60000 + (sqlite3_int64)(p->s*1000);
+ if( p->validTZ ){
+ p->iJD -= p->tz*60000;
+ p->validYMD = 0;
+ p->validHMS = 0;
+ p->validTZ = 0;
+ }
+ }
+}
+
+/*
+** Parse dates of the form
+**
+** YYYY-MM-DD HH:MM:SS.FFF
+** YYYY-MM-DD HH:MM:SS
+** YYYY-MM-DD HH:MM
+** YYYY-MM-DD
+**
+** Write the result into the DateTime structure and return 0
+** on success and 1 if the input string is not a well-formed
+** date.
+*/
+static int parseYyyyMmDd(const char *zDate, DateTime *p){
+ int Y, M, D, neg;
+
+ if( zDate[0]=='-' ){
+ zDate++;
+ neg = 1;
+ }else{
+ neg = 0;
+ }
+ if( getDigits(zDate,4,0,9999,'-',&Y,2,1,12,'-',&M,2,1,31,0,&D)!=3 ){
+ return 1;
+ }
+ zDate += 10;
+ while( sqlite3Isspace(*zDate) || 'T'==*(u8*)zDate ){ zDate++; }
+ if( parseHhMmSs(zDate, p)==0 ){
+ /* We got the time */
+ }else if( *zDate==0 ){
+ p->validHMS = 0;
+ }else{
+ return 1;
+ }
+ p->validJD = 0;
+ p->validYMD = 1;
+ p->Y = neg ? -Y : Y;
+ p->M = M;
+ p->D = D;
+ if( p->validTZ ){
+ computeJD(p);
+ }
+ return 0;
+}
+
+/*
+** Set the time to the current time reported by the VFS.
+**
+** Return the number of errors.
+*/
+static int setDateTimeToCurrent(sqlite3_context *context, DateTime *p){
+ p->iJD = sqlite3StmtCurrentTime(context);
+ if( p->iJD>0 ){
+ p->validJD = 1;
+ return 0;
+ }else{
+ return 1;
+ }
+}
+
+/*
+** Attempt to parse the given string into a Julian Day Number. Return
+** the number of errors.
+**
+** The following are acceptable forms for the input string:
+**
+** YYYY-MM-DD HH:MM:SS.FFF +/-HH:MM
+** DDDD.DD
+** now
+**
+** In the first form, the +/-HH:MM is always optional. The fractional
+** seconds extension (the ".FFF") is optional. The seconds portion
+** (":SS.FFF") is option. The year and date can be omitted as long
+** as there is a time string. The time string can be omitted as long
+** as there is a year and date.
+*/
+static int parseDateOrTime(
+ sqlite3_context *context,
+ const char *zDate,
+ DateTime *p
+){
+ double r;
+ if( parseYyyyMmDd(zDate,p)==0 ){
+ return 0;
+ }else if( parseHhMmSs(zDate, p)==0 ){
+ return 0;
+ }else if( sqlite3StrICmp(zDate,"now")==0){
+ return setDateTimeToCurrent(context, p);
+ }else if( sqlite3AtoF(zDate, &r, sqlite3Strlen30(zDate), SQLITE_UTF8) ){
+ p->iJD = (sqlite3_int64)(r*86400000.0 + 0.5);
+ p->validJD = 1;
+ return 0;
+ }
+ return 1;
+}
+
+/*
+** Compute the Year, Month, and Day from the julian day number.
+*/
+static void computeYMD(DateTime *p){
+ int Z, A, B, C, D, E, X1;
+ if( p->validYMD ) return;
+ if( !p->validJD ){
+ p->Y = 2000;
+ p->M = 1;
+ p->D = 1;
+ }else{
+ Z = (int)((p->iJD + 43200000)/86400000);
+ A = (int)((Z - 1867216.25)/36524.25);
+ A = Z + 1 + A - (A/4);
+ B = A + 1524;
+ C = (int)((B - 122.1)/365.25);
+ D = (36525*C)/100;
+ E = (int)((B-D)/30.6001);
+ X1 = (int)(30.6001*E);
+ p->D = B - D - X1;
+ p->M = E<14 ? E-1 : E-13;
+ p->Y = p->M>2 ? C - 4716 : C - 4715;
+ }
+ p->validYMD = 1;
+}
+
+/*
+** Compute the Hour, Minute, and Seconds from the julian day number.
+*/
+static void computeHMS(DateTime *p){
+ int s;
+ if( p->validHMS ) return;
+ computeJD(p);
+ s = (int)((p->iJD + 43200000) % 86400000);
+ p->s = s/1000.0;
+ s = (int)p->s;
+ p->s -= s;
+ p->h = s/3600;
+ s -= p->h*3600;
+ p->m = s/60;
+ p->s += s - p->m*60;
+ p->validHMS = 1;
+}
+
+/*
+** Compute both YMD and HMS
+*/
+static void computeYMD_HMS(DateTime *p){
+ computeYMD(p);
+ computeHMS(p);
+}
+
+/*
+** Clear the YMD and HMS and the TZ
+*/
+static void clearYMD_HMS_TZ(DateTime *p){
+ p->validYMD = 0;
+ p->validHMS = 0;
+ p->validTZ = 0;
+}
+
+/*
+** On recent Windows platforms, the localtime_s() function is available
+** as part of the "Secure CRT". It is essentially equivalent to
+** localtime_r() available under most POSIX platforms, except that the
+** order of the parameters is reversed.
+**
+** See http://msdn.microsoft.com/en-us/library/a442x3ye(VS.80).aspx.
+**
+** If the user has not indicated to use localtime_r() or localtime_s()
+** already, check for an MSVC build environment that provides
+** localtime_s().
+*/
+#if !defined(HAVE_LOCALTIME_R) && !defined(HAVE_LOCALTIME_S) && \
+ defined(_MSC_VER) && defined(_CRT_INSECURE_DEPRECATE)
+#define HAVE_LOCALTIME_S 1
+#endif
+
+#ifndef SQLITE_OMIT_LOCALTIME
+/*
+** The following routine implements the rough equivalent of localtime_r()
+** using whatever operating-system specific localtime facility that
+** is available. This routine returns 0 on success and
+** non-zero on any kind of error.
+**
+** If the sqlite3GlobalConfig.bLocaltimeFault variable is true then this
+** routine will always fail.
+**
+** EVIDENCE-OF: R-62172-00036 In this implementation, the standard C
+** library function localtime_r() is used to assist in the calculation of
+** local time.
+*/
+static int osLocaltime(time_t *t, struct tm *pTm){
+ int rc;
+#if (!defined(HAVE_LOCALTIME_R) || !HAVE_LOCALTIME_R) \
+ && (!defined(HAVE_LOCALTIME_S) || !HAVE_LOCALTIME_S)
+ struct tm *pX;
+#if SQLITE_THREADSAFE>0
+ sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+ sqlite3_mutex_enter(mutex);
+ pX = localtime(t);
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+ if( sqlite3GlobalConfig.bLocaltimeFault ) pX = 0;
+#endif
+ if( pX ) *pTm = *pX;
+ sqlite3_mutex_leave(mutex);
+ rc = pX==0;
+#else
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+ if( sqlite3GlobalConfig.bLocaltimeFault ) return 1;
+#endif
+#if defined(HAVE_LOCALTIME_R) && HAVE_LOCALTIME_R
+ rc = localtime_r(t, pTm)==0;
+#else
+ rc = localtime_s(pTm, t);
+#endif /* HAVE_LOCALTIME_R */
+#endif /* HAVE_LOCALTIME_R || HAVE_LOCALTIME_S */
+ return rc;
+}
+#endif /* SQLITE_OMIT_LOCALTIME */
+
+
+#ifndef SQLITE_OMIT_LOCALTIME
+/*
+** Compute the difference (in milliseconds) between localtime and UTC
+** (a.k.a. GMT) for the time value p where p is in UTC. If no error occurs,
+** return this value and set *pRc to SQLITE_OK.
+**
+** Or, if an error does occur, set *pRc to SQLITE_ERROR. The returned value
+** is undefined in this case.
+*/
+static sqlite3_int64 localtimeOffset(
+ DateTime *p, /* Date at which to calculate offset */
+ sqlite3_context *pCtx, /* Write error here if one occurs */
+ int *pRc /* OUT: Error code. SQLITE_OK or ERROR */
+){
+ DateTime x, y;
+ time_t t;
+ struct tm sLocal;
+
+ /* Initialize the contents of sLocal to avoid a compiler warning. */
+ memset(&sLocal, 0, sizeof(sLocal));
+
+ x = *p;
+ computeYMD_HMS(&x);
+ if( x.Y<1971 || x.Y>=2038 ){
+ /* EVIDENCE-OF: R-55269-29598 The localtime_r() C function normally only
+ ** works for years between 1970 and 2037. For dates outside this range,
+ ** SQLite attempts to map the year into an equivalent year within this
+ ** range, do the calculation, then map the year back.
+ */
+ x.Y = 2000;
+ x.M = 1;
+ x.D = 1;
+ x.h = 0;
+ x.m = 0;
+ x.s = 0.0;
+ } else {
+ int s = (int)(x.s + 0.5);
+ x.s = s;
+ }
+ x.tz = 0;
+ x.validJD = 0;
+ computeJD(&x);
+ t = (time_t)(x.iJD/1000 - 21086676*(i64)10000);
+ if( osLocaltime(&t, &sLocal) ){
+ sqlite3_result_error(pCtx, "local time unavailable", -1);
+ *pRc = SQLITE_ERROR;
+ return 0;
+ }
+ y.Y = sLocal.tm_year + 1900;
+ y.M = sLocal.tm_mon + 1;
+ y.D = sLocal.tm_mday;
+ y.h = sLocal.tm_hour;
+ y.m = sLocal.tm_min;
+ y.s = sLocal.tm_sec;
+ y.validYMD = 1;
+ y.validHMS = 1;
+ y.validJD = 0;
+ y.validTZ = 0;
+ computeJD(&y);
+ *pRc = SQLITE_OK;
+ return y.iJD - x.iJD;
+}
+#endif /* SQLITE_OMIT_LOCALTIME */
+
+/*
+** Process a modifier to a date-time stamp. The modifiers are
+** as follows:
+**
+** NNN days
+** NNN hours
+** NNN minutes
+** NNN.NNNN seconds
+** NNN months
+** NNN years
+** start of month
+** start of year
+** start of week
+** start of day
+** weekday N
+** unixepoch
+** localtime
+** utc
+**
+** Return 0 on success and 1 if there is any kind of error. If the error
+** is in a system call (i.e. localtime()), then an error message is written
+** to context pCtx. If the error is an unrecognized modifier, no error is
+** written to pCtx.
+*/
+static int parseModifier(sqlite3_context *pCtx, const char *zMod, DateTime *p){
+ int rc = 1;
+ int n;
+ double r;
+ char *z, zBuf[30];
+ z = zBuf;
+ for(n=0; niJD += localtimeOffset(p, pCtx, &rc);
+ clearYMD_HMS_TZ(p);
+ }
+ break;
+ }
+#endif
+ case 'u': {
+ /*
+ ** unixepoch
+ **
+ ** Treat the current value of p->iJD as the number of
+ ** seconds since 1970. Convert to a real julian day number.
+ */
+ if( strcmp(z, "unixepoch")==0 && p->validJD ){
+ p->iJD = (p->iJD + 43200)/86400 + 21086676*(i64)10000000;
+ clearYMD_HMS_TZ(p);
+ rc = 0;
+ }
+#ifndef SQLITE_OMIT_LOCALTIME
+ else if( strcmp(z, "utc")==0 ){
+ sqlite3_int64 c1;
+ computeJD(p);
+ c1 = localtimeOffset(p, pCtx, &rc);
+ if( rc==SQLITE_OK ){
+ p->iJD -= c1;
+ clearYMD_HMS_TZ(p);
+ p->iJD += c1 - localtimeOffset(p, pCtx, &rc);
+ }
+ }
+#endif
+ break;
+ }
+ case 'w': {
+ /*
+ ** weekday N
+ **
+ ** Move the date to the same time on the next occurrence of
+ ** weekday N where 0==Sunday, 1==Monday, and so forth. If the
+ ** date is already on the appropriate weekday, this is a no-op.
+ */
+ if( strncmp(z, "weekday ", 8)==0
+ && sqlite3AtoF(&z[8], &r, sqlite3Strlen30(&z[8]), SQLITE_UTF8)
+ && (n=(int)r)==r && n>=0 && r<7 ){
+ sqlite3_int64 Z;
+ computeYMD_HMS(p);
+ p->validTZ = 0;
+ p->validJD = 0;
+ computeJD(p);
+ Z = ((p->iJD + 129600000)/86400000) % 7;
+ if( Z>n ) Z -= 7;
+ p->iJD += (n - Z)*86400000;
+ clearYMD_HMS_TZ(p);
+ rc = 0;
+ }
+ break;
+ }
+ case 's': {
+ /*
+ ** start of TTTTT
+ **
+ ** Move the date backwards to the beginning of the current day,
+ ** or month or year.
+ */
+ if( strncmp(z, "start of ", 9)!=0 ) break;
+ z += 9;
+ computeYMD(p);
+ p->validHMS = 1;
+ p->h = p->m = 0;
+ p->s = 0.0;
+ p->validTZ = 0;
+ p->validJD = 0;
+ if( strcmp(z,"month")==0 ){
+ p->D = 1;
+ rc = 0;
+ }else if( strcmp(z,"year")==0 ){
+ computeYMD(p);
+ p->M = 1;
+ p->D = 1;
+ rc = 0;
+ }else if( strcmp(z,"day")==0 ){
+ rc = 0;
+ }
+ break;
+ }
+ case '+':
+ case '-':
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9': {
+ double rRounder;
+ for(n=1; z[n] && z[n]!=':' && !sqlite3Isspace(z[n]); n++){}
+ if( !sqlite3AtoF(z, &r, n, SQLITE_UTF8) ){
+ rc = 1;
+ break;
+ }
+ if( z[n]==':' ){
+ /* A modifier of the form (+|-)HH:MM:SS.FFF adds (or subtracts) the
+ ** specified number of hours, minutes, seconds, and fractional seconds
+ ** to the time. The ".FFF" may be omitted. The ":SS.FFF" may be
+ ** omitted.
+ */
+ const char *z2 = z;
+ DateTime tx;
+ sqlite3_int64 day;
+ if( !sqlite3Isdigit(*z2) ) z2++;
+ memset(&tx, 0, sizeof(tx));
+ if( parseHhMmSs(z2, &tx) ) break;
+ computeJD(&tx);
+ tx.iJD -= 43200000;
+ day = tx.iJD/86400000;
+ tx.iJD -= day*86400000;
+ if( z[0]=='-' ) tx.iJD = -tx.iJD;
+ computeJD(p);
+ clearYMD_HMS_TZ(p);
+ p->iJD += tx.iJD;
+ rc = 0;
+ break;
+ }
+ z += n;
+ while( sqlite3Isspace(*z) ) z++;
+ n = sqlite3Strlen30(z);
+ if( n>10 || n<3 ) break;
+ if( z[n-1]=='s' ){ z[n-1] = 0; n--; }
+ computeJD(p);
+ rc = 0;
+ rRounder = r<0 ? -0.5 : +0.5;
+ if( n==3 && strcmp(z,"day")==0 ){
+ p->iJD += (sqlite3_int64)(r*86400000.0 + rRounder);
+ }else if( n==4 && strcmp(z,"hour")==0 ){
+ p->iJD += (sqlite3_int64)(r*(86400000.0/24.0) + rRounder);
+ }else if( n==6 && strcmp(z,"minute")==0 ){
+ p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0)) + rRounder);
+ }else if( n==6 && strcmp(z,"second")==0 ){
+ p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0*60.0)) + rRounder);
+ }else if( n==5 && strcmp(z,"month")==0 ){
+ int x, y;
+ computeYMD_HMS(p);
+ p->M += (int)r;
+ x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
+ p->Y += x;
+ p->M -= x*12;
+ p->validJD = 0;
+ computeJD(p);
+ y = (int)r;
+ if( y!=r ){
+ p->iJD += (sqlite3_int64)((r - y)*30.0*86400000.0 + rRounder);
+ }
+ }else if( n==4 && strcmp(z,"year")==0 ){
+ int y = (int)r;
+ computeYMD_HMS(p);
+ p->Y += y;
+ p->validJD = 0;
+ computeJD(p);
+ if( y!=r ){
+ p->iJD += (sqlite3_int64)((r - y)*365.0*86400000.0 + rRounder);
+ }
+ }else{
+ rc = 1;
+ }
+ clearYMD_HMS_TZ(p);
+ break;
+ }
+ default: {
+ break;
+ }
+ }
+ return rc;
+}
+
+/*
+** Process time function arguments. argv[0] is a date-time stamp.
+** argv[1] and following are modifiers. Parse them all and write
+** the resulting time into the DateTime structure p. Return 0
+** on success and 1 if there are any errors.
+**
+** If there are zero parameters (if even argv[0] is undefined)
+** then assume a default value of "now" for argv[0].
+*/
+static int isDate(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv,
+ DateTime *p
+){
+ int i;
+ const unsigned char *z;
+ int eType;
+ memset(p, 0, sizeof(*p));
+ if( argc==0 ){
+ return setDateTimeToCurrent(context, p);
+ }
+ if( (eType = sqlite3_value_type(argv[0]))==SQLITE_FLOAT
+ || eType==SQLITE_INTEGER ){
+ p->iJD = (sqlite3_int64)(sqlite3_value_double(argv[0])*86400000.0 + 0.5);
+ p->validJD = 1;
+ }else{
+ z = sqlite3_value_text(argv[0]);
+ if( !z || parseDateOrTime(context, (char*)z, p) ){
+ return 1;
+ }
+ }
+ for(i=1; iaLimit[SQLITE_LIMIT_LENGTH]+1 );
+ testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH] );
+ if( n(u64)db->aLimit[SQLITE_LIMIT_LENGTH] ){
+ sqlite3_result_error_toobig(context);
+ return;
+ }else{
+ z = sqlite3DbMallocRaw(db, (int)n);
+ if( z==0 ){
+ sqlite3_result_error_nomem(context);
+ return;
+ }
+ }
+ computeJD(&x);
+ computeYMD_HMS(&x);
+ for(i=j=0; zFmt[i]; i++){
+ if( zFmt[i]!='%' ){
+ z[j++] = zFmt[i];
+ }else{
+ i++;
+ switch( zFmt[i] ){
+ case 'd': sqlite3_snprintf(3, &z[j],"%02d",x.D); j+=2; break;
+ case 'f': {
+ double s = x.s;
+ if( s>59.999 ) s = 59.999;
+ sqlite3_snprintf(7, &z[j],"%06.3f", s);
+ j += sqlite3Strlen30(&z[j]);
+ break;
+ }
+ case 'H': sqlite3_snprintf(3, &z[j],"%02d",x.h); j+=2; break;
+ case 'W': /* Fall thru */
+ case 'j': {
+ int nDay; /* Number of days since 1st day of year */
+ DateTime y = x;
+ y.validJD = 0;
+ y.M = 1;
+ y.D = 1;
+ computeJD(&y);
+ nDay = (int)((x.iJD-y.iJD+43200000)/86400000);
+ if( zFmt[i]=='W' ){
+ int wd; /* 0=Monday, 1=Tuesday, ... 6=Sunday */
+ wd = (int)(((x.iJD+43200000)/86400000)%7);
+ sqlite3_snprintf(3, &z[j],"%02d",(nDay+7-wd)/7);
+ j += 2;
+ }else{
+ sqlite3_snprintf(4, &z[j],"%03d",nDay+1);
+ j += 3;
+ }
+ break;
+ }
+ case 'J': {
+ sqlite3_snprintf(20, &z[j],"%.16g",x.iJD/86400000.0);
+ j+=sqlite3Strlen30(&z[j]);
+ break;
+ }
+ case 'm': sqlite3_snprintf(3, &z[j],"%02d",x.M); j+=2; break;
+ case 'M': sqlite3_snprintf(3, &z[j],"%02d",x.m); j+=2; break;
+ case 's': {
+ sqlite3_snprintf(30,&z[j],"%lld",
+ (i64)(x.iJD/1000 - 21086676*(i64)10000));
+ j += sqlite3Strlen30(&z[j]);
+ break;
+ }
+ case 'S': sqlite3_snprintf(3,&z[j],"%02d",(int)x.s); j+=2; break;
+ case 'w': {
+ z[j++] = (char)(((x.iJD+129600000)/86400000) % 7) + '0';
+ break;
+ }
+ case 'Y': {
+ sqlite3_snprintf(5,&z[j],"%04d",x.Y); j+=sqlite3Strlen30(&z[j]);
+ break;
+ }
+ default: z[j++] = '%'; break;
+ }
+ }
+ }
+ z[j] = 0;
+ sqlite3_result_text(context, z, -1,
+ z==zBuf ? SQLITE_TRANSIENT : SQLITE_DYNAMIC);
+}
+
+/*
+** current_time()
+**
+** This function returns the same value as time('now').
+*/
+static void ctimeFunc(
+ sqlite3_context *context,
+ int NotUsed,
+ sqlite3_value **NotUsed2
+){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ timeFunc(context, 0, 0);
+}
+
+/*
+** current_date()
+**
+** This function returns the same value as date('now').
+*/
+static void cdateFunc(
+ sqlite3_context *context,
+ int NotUsed,
+ sqlite3_value **NotUsed2
+){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ dateFunc(context, 0, 0);
+}
+
+/*
+** current_timestamp()
+**
+** This function returns the same value as datetime('now').
+*/
+static void ctimestampFunc(
+ sqlite3_context *context,
+ int NotUsed,
+ sqlite3_value **NotUsed2
+){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ datetimeFunc(context, 0, 0);
+}
+#endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */
+
+#ifdef SQLITE_OMIT_DATETIME_FUNCS
+/*
+** If the library is compiled to omit the full-scale date and time
+** handling (to get a smaller binary), the following minimal version
+** of the functions current_time(), current_date() and current_timestamp()
+** are included instead. This is to support column declarations that
+** include "DEFAULT CURRENT_TIME" etc.
+**
+** This function uses the C-library functions time(), gmtime()
+** and strftime(). The format string to pass to strftime() is supplied
+** as the user-data for the function.
+*/
+static void currentTimeFunc(
+ sqlite3_context *context,
+ int argc,
+ sqlite3_value **argv
+){
+ time_t t;
+ char *zFormat = (char *)sqlite3_user_data(context);
+ sqlite3 *db;
+ sqlite3_int64 iT;
+ struct tm *pTm;
+ struct tm sNow;
+ char zBuf[20];
+
+ UNUSED_PARAMETER(argc);
+ UNUSED_PARAMETER(argv);
+
+ iT = sqlite3StmtCurrentTime(context);
+ if( iT<=0 ) return;
+ t = iT/1000 - 10000*(sqlite3_int64)21086676;
+#ifdef HAVE_GMTIME_R
+ pTm = gmtime_r(&t, &sNow);
+#else
+ sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+ pTm = gmtime(&t);
+ if( pTm ) memcpy(&sNow, pTm, sizeof(sNow));
+ sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+#endif
+ if( pTm ){
+ strftime(zBuf, 20, zFormat, &sNow);
+ sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
+ }
+}
+#endif
+
+/*
+** This function registered all of the above C functions as SQL
+** functions. This should be the only routine in this file with
+** external linkage.
+*/
+SQLITE_PRIVATE void sqlite3RegisterDateTimeFunctions(void){
+ static SQLITE_WSD FuncDef aDateTimeFuncs[] = {
+#ifndef SQLITE_OMIT_DATETIME_FUNCS
+ FUNCTION(julianday, -1, 0, 0, juliandayFunc ),
+ FUNCTION(date, -1, 0, 0, dateFunc ),
+ FUNCTION(time, -1, 0, 0, timeFunc ),
+ FUNCTION(datetime, -1, 0, 0, datetimeFunc ),
+ FUNCTION(strftime, -1, 0, 0, strftimeFunc ),
+ FUNCTION(current_time, 0, 0, 0, ctimeFunc ),
+ FUNCTION(current_timestamp, 0, 0, 0, ctimestampFunc),
+ FUNCTION(current_date, 0, 0, 0, cdateFunc ),
+#else
+ STR_FUNCTION(current_time, 0, "%H:%M:%S", 0, currentTimeFunc),
+ STR_FUNCTION(current_date, 0, "%Y-%m-%d", 0, currentTimeFunc),
+ STR_FUNCTION(current_timestamp, 0, "%Y-%m-%d %H:%M:%S", 0, currentTimeFunc),
+#endif
+ };
+ int i;
+ FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
+ FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aDateTimeFuncs);
+
+ for(i=0; ipMethods ){
+ rc = pId->pMethods->xClose(pId);
+ pId->pMethods = 0;
+ }
+ return rc;
+}
+SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file *id, void *pBuf, int amt, i64 offset){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xRead(id, pBuf, amt, offset);
+}
+SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file *id, const void *pBuf, int amt, i64 offset){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xWrite(id, pBuf, amt, offset);
+}
+SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file *id, i64 size){
+ return id->pMethods->xTruncate(id, size);
+}
+SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file *id, int flags){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xSync(id, flags);
+}
+SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file *id, i64 *pSize){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xFileSize(id, pSize);
+}
+SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file *id, int lockType){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xLock(id, lockType);
+}
+SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file *id, int lockType){
+ return id->pMethods->xUnlock(id, lockType);
+}
+SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xCheckReservedLock(id, pResOut);
+}
+
+/*
+** Use sqlite3OsFileControl() when we are doing something that might fail
+** and we need to know about the failures. Use sqlite3OsFileControlHint()
+** when simply tossing information over the wall to the VFS and we do not
+** really care if the VFS receives and understands the information since it
+** is only a hint and can be safely ignored. The sqlite3OsFileControlHint()
+** routine has no return value since the return value would be meaningless.
+*/
+SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file *id, int op, void *pArg){
+#ifdef SQLITE_TEST
+ if( op!=SQLITE_FCNTL_COMMIT_PHASETWO ){
+ /* Faults are not injected into COMMIT_PHASETWO because, assuming SQLite
+ ** is using a regular VFS, it is called after the corresponding
+ ** transaction has been committed. Injecting a fault at this point
+ ** confuses the test scripts - the COMMIT comand returns SQLITE_NOMEM
+ ** but the transaction is committed anyway.
+ **
+ ** The core must call OsFileControl() though, not OsFileControlHint(),
+ ** as if a custom VFS (e.g. zipvfs) returns an error here, it probably
+ ** means the commit really has failed and an error should be returned
+ ** to the user. */
+ DO_OS_MALLOC_TEST(id);
+ }
+#endif
+ return id->pMethods->xFileControl(id, op, pArg);
+}
+SQLITE_PRIVATE void sqlite3OsFileControlHint(sqlite3_file *id, int op, void *pArg){
+ (void)id->pMethods->xFileControl(id, op, pArg);
+}
+
+SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id){
+ int (*xSectorSize)(sqlite3_file*) = id->pMethods->xSectorSize;
+ return (xSectorSize ? xSectorSize(id) : SQLITE_DEFAULT_SECTOR_SIZE);
+}
+SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id){
+ return id->pMethods->xDeviceCharacteristics(id);
+}
+SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int offset, int n, int flags){
+ return id->pMethods->xShmLock(id, offset, n, flags);
+}
+SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id){
+ id->pMethods->xShmBarrier(id);
+}
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int deleteFlag){
+ return id->pMethods->xShmUnmap(id, deleteFlag);
+}
+SQLITE_PRIVATE int sqlite3OsShmMap(
+ sqlite3_file *id, /* Database file handle */
+ int iPage,
+ int pgsz,
+ int bExtend, /* True to extend file if necessary */
+ void volatile **pp /* OUT: Pointer to mapping */
+){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xShmMap(id, iPage, pgsz, bExtend, pp);
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/* The real implementation of xFetch and xUnfetch */
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64 iOff, int iAmt, void **pp){
+ DO_OS_MALLOC_TEST(id);
+ return id->pMethods->xFetch(id, iOff, iAmt, pp);
+}
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *id, i64 iOff, void *p){
+ return id->pMethods->xUnfetch(id, iOff, p);
+}
+#else
+/* No-op stubs to use when memory-mapped I/O is disabled */
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64 iOff, int iAmt, void **pp){
+ *pp = 0;
+ return SQLITE_OK;
+}
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *id, i64 iOff, void *p){
+ return SQLITE_OK;
+}
+#endif
+
+/*
+** The next group of routines are convenience wrappers around the
+** VFS methods.
+*/
+SQLITE_PRIVATE int sqlite3OsOpen(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ sqlite3_file *pFile,
+ int flags,
+ int *pFlagsOut
+){
+ int rc;
+ DO_OS_MALLOC_TEST(0);
+ /* 0x87f7f is a mask of SQLITE_OPEN_ flags that are valid to be passed
+ ** down into the VFS layer. Some SQLITE_OPEN_ flags (for example,
+ ** SQLITE_OPEN_FULLMUTEX or SQLITE_OPEN_SHAREDCACHE) are blocked before
+ ** reaching the VFS. */
+ rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x87f7f, pFlagsOut);
+ assert( rc==SQLITE_OK || pFile->pMethods==0 );
+ return rc;
+}
+SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
+ DO_OS_MALLOC_TEST(0);
+ assert( dirSync==0 || dirSync==1 );
+ return pVfs->xDelete(pVfs, zPath, dirSync);
+}
+SQLITE_PRIVATE int sqlite3OsAccess(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ int flags,
+ int *pResOut
+){
+ DO_OS_MALLOC_TEST(0);
+ return pVfs->xAccess(pVfs, zPath, flags, pResOut);
+}
+SQLITE_PRIVATE int sqlite3OsFullPathname(
+ sqlite3_vfs *pVfs,
+ const char *zPath,
+ int nPathOut,
+ char *zPathOut
+){
+ DO_OS_MALLOC_TEST(0);
+ zPathOut[0] = 0;
+ return pVfs->xFullPathname(pVfs, zPath, nPathOut, zPathOut);
+}
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
+ return pVfs->xDlOpen(pVfs, zPath);
+}
+SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
+ pVfs->xDlError(pVfs, nByte, zBufOut);
+}
+SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *pVfs, void *pHdle, const char *zSym))(void){
+ return pVfs->xDlSym(pVfs, pHdle, zSym);
+}
+SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *pVfs, void *pHandle){
+ pVfs->xDlClose(pVfs, pHandle);
+}
+#endif /* SQLITE_OMIT_LOAD_EXTENSION */
+SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
+ return pVfs->xRandomness(pVfs, nByte, zBufOut);
+}
+SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *pVfs, int nMicro){
+ return pVfs->xSleep(pVfs, nMicro);
+}
+SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){
+ int rc;
+ /* IMPLEMENTATION-OF: R-49045-42493 SQLite will use the xCurrentTimeInt64()
+ ** method to get the current date and time if that method is available
+ ** (if iVersion is 2 or greater and the function pointer is not NULL) and
+ ** will fall back to xCurrentTime() if xCurrentTimeInt64() is
+ ** unavailable.
+ */
+ if( pVfs->iVersion>=2 && pVfs->xCurrentTimeInt64 ){
+ rc = pVfs->xCurrentTimeInt64(pVfs, pTimeOut);
+ }else{
+ double r;
+ rc = pVfs->xCurrentTime(pVfs, &r);
+ *pTimeOut = (sqlite3_int64)(r*86400000.0);
+ }
+ return rc;
+}
+
+SQLITE_PRIVATE int sqlite3OsOpenMalloc(
+ sqlite3_vfs *pVfs,
+ const char *zFile,
+ sqlite3_file **ppFile,
+ int flags,
+ int *pOutFlags
+){
+ int rc = SQLITE_NOMEM;
+ sqlite3_file *pFile;
+ pFile = (sqlite3_file *)sqlite3MallocZero(pVfs->szOsFile);
+ if( pFile ){
+ rc = sqlite3OsOpen(pVfs, zFile, pFile, flags, pOutFlags);
+ if( rc!=SQLITE_OK ){
+ sqlite3_free(pFile);
+ }else{
+ *ppFile = pFile;
+ }
+ }
+ return rc;
+}
+SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *pFile){
+ int rc = SQLITE_OK;
+ assert( pFile );
+ rc = sqlite3OsClose(pFile);
+ sqlite3_free(pFile);
+ return rc;
+}
+
+/*
+** This function is a wrapper around the OS specific implementation of
+** sqlite3_os_init(). The purpose of the wrapper is to provide the
+** ability to simulate a malloc failure, so that the handling of an
+** error in sqlite3_os_init() by the upper layers can be tested.
+*/
+SQLITE_PRIVATE int sqlite3OsInit(void){
+ void *p = sqlite3_malloc(10);
+ if( p==0 ) return SQLITE_NOMEM;
+ sqlite3_free(p);
+ return sqlite3_os_init();
+}
+
+/*
+** The list of all registered VFS implementations.
+*/
+static sqlite3_vfs * SQLITE_WSD vfsList = 0;
+#define vfsList GLOBAL(sqlite3_vfs *, vfsList)
+
+/*
+** Locate a VFS by name. If no name is given, simply return the
+** first VFS on the list.
+*/
+SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
+ sqlite3_vfs *pVfs = 0;
+#if SQLITE_THREADSAFE
+ sqlite3_mutex *mutex;
+#endif
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return 0;
+#endif
+#if SQLITE_THREADSAFE
+ mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+ sqlite3_mutex_enter(mutex);
+ for(pVfs = vfsList; pVfs; pVfs=pVfs->pNext){
+ if( zVfs==0 ) break;
+ if( strcmp(zVfs, pVfs->zName)==0 ) break;
+ }
+ sqlite3_mutex_leave(mutex);
+ return pVfs;
+}
+
+/*
+** Unlink a VFS from the linked list
+*/
+static void vfsUnlink(sqlite3_vfs *pVfs){
+ assert( sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER)) );
+ if( pVfs==0 ){
+ /* No-op */
+ }else if( vfsList==pVfs ){
+ vfsList = pVfs->pNext;
+ }else if( vfsList ){
+ sqlite3_vfs *p = vfsList;
+ while( p->pNext && p->pNext!=pVfs ){
+ p = p->pNext;
+ }
+ if( p->pNext==pVfs ){
+ p->pNext = pVfs->pNext;
+ }
+ }
+}
+
+/*
+** Register a VFS with the system. It is harmless to register the same
+** VFS multiple times. The new VFS becomes the default if makeDflt is
+** true.
+*/
+SQLITE_API int sqlite3_vfs_register(sqlite3_vfs *pVfs, int makeDflt){
+ MUTEX_LOGIC(sqlite3_mutex *mutex;)
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return rc;
+#endif
+ MUTEX_LOGIC( mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER); )
+ sqlite3_mutex_enter(mutex);
+ vfsUnlink(pVfs);
+ if( makeDflt || vfsList==0 ){
+ pVfs->pNext = vfsList;
+ vfsList = pVfs;
+ }else{
+ pVfs->pNext = vfsList->pNext;
+ vfsList->pNext = pVfs;
+ }
+ assert(vfsList);
+ sqlite3_mutex_leave(mutex);
+ return SQLITE_OK;
+}
+
+/*
+** Unregister a VFS so that it is no longer accessible.
+*/
+SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs *pVfs){
+#if SQLITE_THREADSAFE
+ sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+ sqlite3_mutex_enter(mutex);
+ vfsUnlink(pVfs);
+ sqlite3_mutex_leave(mutex);
+ return SQLITE_OK;
+}
+
+/************** End of os.c **************************************************/
+/************** Begin file fault.c *******************************************/
+/*
+** 2008 Jan 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains code to support the concept of "benign"
+** malloc failures (when the xMalloc() or xRealloc() method of the
+** sqlite3_mem_methods structure fails to allocate a block of memory
+** and returns 0).
+**
+** Most malloc failures are non-benign. After they occur, SQLite
+** abandons the current operation and returns an error code (usually
+** SQLITE_NOMEM) to the user. However, sometimes a fault is not necessarily
+** fatal. For example, if a malloc fails while resizing a hash table, this
+** is completely recoverable simply by not carrying out the resize. The
+** hash table will continue to function normally. So a malloc failure
+** during a hash table resize is a benign fault.
+*/
+
+
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+
+/*
+** Global variables.
+*/
+typedef struct BenignMallocHooks BenignMallocHooks;
+static SQLITE_WSD struct BenignMallocHooks {
+ void (*xBenignBegin)(void);
+ void (*xBenignEnd)(void);
+} sqlite3Hooks = { 0, 0 };
+
+/* The "wsdHooks" macro will resolve to the appropriate BenignMallocHooks
+** structure. If writable static data is unsupported on the target,
+** we have to locate the state vector at run-time. In the more common
+** case where writable static data is supported, wsdHooks can refer directly
+** to the "sqlite3Hooks" state vector declared above.
+*/
+#ifdef SQLITE_OMIT_WSD
+# define wsdHooksInit \
+ BenignMallocHooks *x = &GLOBAL(BenignMallocHooks,sqlite3Hooks)
+# define wsdHooks x[0]
+#else
+# define wsdHooksInit
+# define wsdHooks sqlite3Hooks
+#endif
+
+
+/*
+** Register hooks to call when sqlite3BeginBenignMalloc() and
+** sqlite3EndBenignMalloc() are called, respectively.
+*/
+SQLITE_PRIVATE void sqlite3BenignMallocHooks(
+ void (*xBenignBegin)(void),
+ void (*xBenignEnd)(void)
+){
+ wsdHooksInit;
+ wsdHooks.xBenignBegin = xBenignBegin;
+ wsdHooks.xBenignEnd = xBenignEnd;
+}
+
+/*
+** This (sqlite3EndBenignMalloc()) is called by SQLite code to indicate that
+** subsequent malloc failures are benign. A call to sqlite3EndBenignMalloc()
+** indicates that subsequent malloc failures are non-benign.
+*/
+SQLITE_PRIVATE void sqlite3BeginBenignMalloc(void){
+ wsdHooksInit;
+ if( wsdHooks.xBenignBegin ){
+ wsdHooks.xBenignBegin();
+ }
+}
+SQLITE_PRIVATE void sqlite3EndBenignMalloc(void){
+ wsdHooksInit;
+ if( wsdHooks.xBenignEnd ){
+ wsdHooks.xBenignEnd();
+ }
+}
+
+#endif /* #ifndef SQLITE_OMIT_BUILTIN_TEST */
+
+/************** End of fault.c ***********************************************/
+/************** Begin file mem0.c ********************************************/
+/*
+** 2008 October 28
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains a no-op memory allocation drivers for use when
+** SQLITE_ZERO_MALLOC is defined. The allocation drivers implemented
+** here always fail. SQLite will not operate with these drivers. These
+** are merely placeholders. Real drivers must be substituted using
+** sqlite3_config() before SQLite will operate.
+*/
+
+/*
+** This version of the memory allocator is the default. It is
+** used when no other memory allocator is specified using compile-time
+** macros.
+*/
+#ifdef SQLITE_ZERO_MALLOC
+
+/*
+** No-op versions of all memory allocation routines
+*/
+static void *sqlite3MemMalloc(int nByte){ return 0; }
+static void sqlite3MemFree(void *pPrior){ return; }
+static void *sqlite3MemRealloc(void *pPrior, int nByte){ return 0; }
+static int sqlite3MemSize(void *pPrior){ return 0; }
+static int sqlite3MemRoundup(int n){ return n; }
+static int sqlite3MemInit(void *NotUsed){ return SQLITE_OK; }
+static void sqlite3MemShutdown(void *NotUsed){ return; }
+
+/*
+** This routine is the only routine in this file with external linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ static const sqlite3_mem_methods defaultMethods = {
+ sqlite3MemMalloc,
+ sqlite3MemFree,
+ sqlite3MemRealloc,
+ sqlite3MemSize,
+ sqlite3MemRoundup,
+ sqlite3MemInit,
+ sqlite3MemShutdown,
+ 0
+ };
+ sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
+}
+
+#endif /* SQLITE_ZERO_MALLOC */
+
+/************** End of mem0.c ************************************************/
+/************** Begin file mem1.c ********************************************/
+/*
+** 2007 August 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains low-level memory allocation drivers for when
+** SQLite will use the standard C-library malloc/realloc/free interface
+** to obtain the memory it needs.
+**
+** This file contains implementations of the low-level memory allocation
+** routines specified in the sqlite3_mem_methods object. The content of
+** this file is only used if SQLITE_SYSTEM_MALLOC is defined. The
+** SQLITE_SYSTEM_MALLOC macro is defined automatically if neither the
+** SQLITE_MEMDEBUG nor the SQLITE_WIN32_MALLOC macros are defined. The
+** default configuration is to use memory allocation routines in this
+** file.
+**
+** C-preprocessor macro summary:
+**
+** HAVE_MALLOC_USABLE_SIZE The configure script sets this symbol if
+** the malloc_usable_size() interface exists
+** on the target platform. Or, this symbol
+** can be set manually, if desired.
+** If an equivalent interface exists by
+** a different name, using a separate -D
+** option to rename it.
+**
+** SQLITE_WITHOUT_ZONEMALLOC Some older macs lack support for the zone
+** memory allocator. Set this symbol to enable
+** building on older macs.
+**
+** SQLITE_WITHOUT_MSIZE Set this symbol to disable the use of
+** _msize() on windows systems. This might
+** be necessary when compiling for Delphi,
+** for example.
+*/
+
+/*
+** This version of the memory allocator is the default. It is
+** used when no other memory allocator is specified using compile-time
+** macros.
+*/
+#ifdef SQLITE_SYSTEM_MALLOC
+#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC)
+
+/*
+** Use the zone allocator available on apple products unless the
+** SQLITE_WITHOUT_ZONEMALLOC symbol is defined.
+*/
+#include
+#include
+#include
+static malloc_zone_t* _sqliteZone_;
+#define SQLITE_MALLOC(x) malloc_zone_malloc(_sqliteZone_, (x))
+#define SQLITE_FREE(x) malloc_zone_free(_sqliteZone_, (x));
+#define SQLITE_REALLOC(x,y) malloc_zone_realloc(_sqliteZone_, (x), (y))
+#define SQLITE_MALLOCSIZE(x) \
+ (_sqliteZone_ ? _sqliteZone_->size(_sqliteZone_,x) : malloc_size(x))
+
+#else /* if not __APPLE__ */
+
+/*
+** Use standard C library malloc and free on non-Apple systems.
+** Also used by Apple systems if SQLITE_WITHOUT_ZONEMALLOC is defined.
+*/
+#define SQLITE_MALLOC(x) malloc(x)
+#define SQLITE_FREE(x) free(x)
+#define SQLITE_REALLOC(x,y) realloc((x),(y))
+
+/*
+** The malloc.h header file is needed for malloc_usable_size() function
+** on some systems (e.g. Linux).
+*/
+#if defined(HAVE_MALLOC_H) && defined(HAVE_MALLOC_USABLE_SIZE)
+# define SQLITE_USE_MALLOC_H
+# define SQLITE_USE_MALLOC_USABLE_SIZE
+/*
+** The MSVCRT has malloc_usable_size(), but it is called _msize(). The
+** use of _msize() is automatic, but can be disabled by compiling with
+** -DSQLITE_WITHOUT_MSIZE. Using the _msize() function also requires
+** the malloc.h header file.
+*/
+#elif defined(_MSC_VER) && !defined(SQLITE_WITHOUT_MSIZE)
+# define SQLITE_USE_MALLOC_H
+# define SQLITE_USE_MSIZE
+#endif
+
+/*
+** Include the malloc.h header file, if necessary. Also set define macro
+** SQLITE_MALLOCSIZE to the appropriate function name, which is _msize()
+** for MSVC and malloc_usable_size() for most other systems (e.g. Linux).
+** The memory size function can always be overridden manually by defining
+** the macro SQLITE_MALLOCSIZE to the desired function name.
+*/
+#if defined(SQLITE_USE_MALLOC_H)
+# include
+# if defined(SQLITE_USE_MALLOC_USABLE_SIZE)
+# if !defined(SQLITE_MALLOCSIZE)
+# define SQLITE_MALLOCSIZE(x) malloc_usable_size(x)
+# endif
+# elif defined(SQLITE_USE_MSIZE)
+# if !defined(SQLITE_MALLOCSIZE)
+# define SQLITE_MALLOCSIZE _msize
+# endif
+# endif
+#endif /* defined(SQLITE_USE_MALLOC_H) */
+
+#endif /* __APPLE__ or not __APPLE__ */
+
+/*
+** Like malloc(), but remember the size of the allocation
+** so that we can find it later using sqlite3MemSize().
+**
+** For this low-level routine, we are guaranteed that nByte>0 because
+** cases of nByte<=0 will be intercepted and dealt with by higher level
+** routines.
+*/
+static void *sqlite3MemMalloc(int nByte){
+#ifdef SQLITE_MALLOCSIZE
+ void *p = SQLITE_MALLOC( nByte );
+ if( p==0 ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes of memory", nByte);
+ }
+ return p;
+#else
+ sqlite3_int64 *p;
+ assert( nByte>0 );
+ nByte = ROUND8(nByte);
+ p = SQLITE_MALLOC( nByte+8 );
+ if( p ){
+ p[0] = nByte;
+ p++;
+ }else{
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes of memory", nByte);
+ }
+ return (void *)p;
+#endif
+}
+
+/*
+** Like free() but works for allocations obtained from sqlite3MemMalloc()
+** or sqlite3MemRealloc().
+**
+** For this low-level routine, we already know that pPrior!=0 since
+** cases where pPrior==0 will have been intecepted and dealt with
+** by higher-level routines.
+*/
+static void sqlite3MemFree(void *pPrior){
+#ifdef SQLITE_MALLOCSIZE
+ SQLITE_FREE(pPrior);
+#else
+ sqlite3_int64 *p = (sqlite3_int64*)pPrior;
+ assert( pPrior!=0 );
+ p--;
+ SQLITE_FREE(p);
+#endif
+}
+
+/*
+** Report the allocated size of a prior return from xMalloc()
+** or xRealloc().
+*/
+static int sqlite3MemSize(void *pPrior){
+#ifdef SQLITE_MALLOCSIZE
+ return pPrior ? (int)SQLITE_MALLOCSIZE(pPrior) : 0;
+#else
+ sqlite3_int64 *p;
+ if( pPrior==0 ) return 0;
+ p = (sqlite3_int64*)pPrior;
+ p--;
+ return (int)p[0];
+#endif
+}
+
+/*
+** Like realloc(). Resize an allocation previously obtained from
+** sqlite3MemMalloc().
+**
+** For this low-level interface, we know that pPrior!=0. Cases where
+** pPrior==0 while have been intercepted by higher-level routine and
+** redirected to xMalloc. Similarly, we know that nByte>0 becauses
+** cases where nByte<=0 will have been intercepted by higher-level
+** routines and redirected to xFree.
+*/
+static void *sqlite3MemRealloc(void *pPrior, int nByte){
+#ifdef SQLITE_MALLOCSIZE
+ void *p = SQLITE_REALLOC(pPrior, nByte);
+ if( p==0 ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM,
+ "failed memory resize %u to %u bytes",
+ SQLITE_MALLOCSIZE(pPrior), nByte);
+ }
+ return p;
+#else
+ sqlite3_int64 *p = (sqlite3_int64*)pPrior;
+ assert( pPrior!=0 && nByte>0 );
+ assert( nByte==ROUND8(nByte) ); /* EV: R-46199-30249 */
+ p--;
+ p = SQLITE_REALLOC(p, nByte+8 );
+ if( p ){
+ p[0] = nByte;
+ p++;
+ }else{
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM,
+ "failed memory resize %u to %u bytes",
+ sqlite3MemSize(pPrior), nByte);
+ }
+ return (void*)p;
+#endif
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int sqlite3MemRoundup(int n){
+ return ROUND8(n);
+}
+
+/*
+** Initialize this module.
+*/
+static int sqlite3MemInit(void *NotUsed){
+#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC)
+ int cpuCount;
+ size_t len;
+ if( _sqliteZone_ ){
+ return SQLITE_OK;
+ }
+ len = sizeof(cpuCount);
+ /* One usually wants to use hw.acctivecpu for MT decisions, but not here */
+ sysctlbyname("hw.ncpu", &cpuCount, &len, NULL, 0);
+ if( cpuCount>1 ){
+ /* defer MT decisions to system malloc */
+ _sqliteZone_ = malloc_default_zone();
+ }else{
+ /* only 1 core, use our own zone to contention over global locks,
+ ** e.g. we have our own dedicated locks */
+ bool success;
+ malloc_zone_t* newzone = malloc_create_zone(4096, 0);
+ malloc_set_zone_name(newzone, "Sqlite_Heap");
+ do{
+ success = OSAtomicCompareAndSwapPtrBarrier(NULL, newzone,
+ (void * volatile *)&_sqliteZone_);
+ }while(!_sqliteZone_);
+ if( !success ){
+ /* somebody registered a zone first */
+ malloc_destroy_zone(newzone);
+ }
+ }
+#endif
+ UNUSED_PARAMETER(NotUsed);
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void sqlite3MemShutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ return;
+}
+
+/*
+** This routine is the only routine in this file with external linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ static const sqlite3_mem_methods defaultMethods = {
+ sqlite3MemMalloc,
+ sqlite3MemFree,
+ sqlite3MemRealloc,
+ sqlite3MemSize,
+ sqlite3MemRoundup,
+ sqlite3MemInit,
+ sqlite3MemShutdown,
+ 0
+ };
+ sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
+}
+
+#endif /* SQLITE_SYSTEM_MALLOC */
+
+/************** End of mem1.c ************************************************/
+/************** Begin file mem2.c ********************************************/
+/*
+** 2007 August 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains low-level memory allocation drivers for when
+** SQLite will use the standard C-library malloc/realloc/free interface
+** to obtain the memory it needs while adding lots of additional debugging
+** information to each allocation in order to help detect and fix memory
+** leaks and memory usage errors.
+**
+** This file contains implementations of the low-level memory allocation
+** routines specified in the sqlite3_mem_methods object.
+*/
+
+/*
+** This version of the memory allocator is used only if the
+** SQLITE_MEMDEBUG macro is defined
+*/
+#ifdef SQLITE_MEMDEBUG
+
+/*
+** The backtrace functionality is only available with GLIBC
+*/
+#ifdef __GLIBC__
+ extern int backtrace(void**,int);
+ extern void backtrace_symbols_fd(void*const*,int,int);
+#else
+# define backtrace(A,B) 1
+# define backtrace_symbols_fd(A,B,C)
+#endif
+/* #include */
+
+/*
+** Each memory allocation looks like this:
+**
+** ------------------------------------------------------------------------
+** | Title | backtrace pointers | MemBlockHdr | allocation | EndGuard |
+** ------------------------------------------------------------------------
+**
+** The application code sees only a pointer to the allocation. We have
+** to back up from the allocation pointer to find the MemBlockHdr. The
+** MemBlockHdr tells us the size of the allocation and the number of
+** backtrace pointers. There is also a guard word at the end of the
+** MemBlockHdr.
+*/
+struct MemBlockHdr {
+ i64 iSize; /* Size of this allocation */
+ struct MemBlockHdr *pNext, *pPrev; /* Linked list of all unfreed memory */
+ char nBacktrace; /* Number of backtraces on this alloc */
+ char nBacktraceSlots; /* Available backtrace slots */
+ u8 nTitle; /* Bytes of title; includes '\0' */
+ u8 eType; /* Allocation type code */
+ int iForeGuard; /* Guard word for sanity */
+};
+
+/*
+** Guard words
+*/
+#define FOREGUARD 0x80F5E153
+#define REARGUARD 0xE4676B53
+
+/*
+** Number of malloc size increments to track.
+*/
+#define NCSIZE 1000
+
+/*
+** All of the static variables used by this module are collected
+** into a single structure named "mem". This is to keep the
+** static variables organized and to reduce namespace pollution
+** when this module is combined with other in the amalgamation.
+*/
+static struct {
+
+ /*
+ ** Mutex to control access to the memory allocation subsystem.
+ */
+ sqlite3_mutex *mutex;
+
+ /*
+ ** Head and tail of a linked list of all outstanding allocations
+ */
+ struct MemBlockHdr *pFirst;
+ struct MemBlockHdr *pLast;
+
+ /*
+ ** The number of levels of backtrace to save in new allocations.
+ */
+ int nBacktrace;
+ void (*xBacktrace)(int, int, void **);
+
+ /*
+ ** Title text to insert in front of each block
+ */
+ int nTitle; /* Bytes of zTitle to save. Includes '\0' and padding */
+ char zTitle[100]; /* The title text */
+
+ /*
+ ** sqlite3MallocDisallow() increments the following counter.
+ ** sqlite3MallocAllow() decrements it.
+ */
+ int disallow; /* Do not allow memory allocation */
+
+ /*
+ ** Gather statistics on the sizes of memory allocations.
+ ** nAlloc[i] is the number of allocation attempts of i*8
+ ** bytes. i==NCSIZE is the number of allocation attempts for
+ ** sizes more than NCSIZE*8 bytes.
+ */
+ int nAlloc[NCSIZE]; /* Total number of allocations */
+ int nCurrent[NCSIZE]; /* Current number of allocations */
+ int mxCurrent[NCSIZE]; /* Highwater mark for nCurrent */
+
+} mem;
+
+
+/*
+** Adjust memory usage statistics
+*/
+static void adjustStats(int iSize, int increment){
+ int i = ROUND8(iSize)/8;
+ if( i>NCSIZE-1 ){
+ i = NCSIZE - 1;
+ }
+ if( increment>0 ){
+ mem.nAlloc[i]++;
+ mem.nCurrent[i]++;
+ if( mem.nCurrent[i]>mem.mxCurrent[i] ){
+ mem.mxCurrent[i] = mem.nCurrent[i];
+ }
+ }else{
+ mem.nCurrent[i]--;
+ assert( mem.nCurrent[i]>=0 );
+ }
+}
+
+/*
+** Given an allocation, find the MemBlockHdr for that allocation.
+**
+** This routine checks the guards at either end of the allocation and
+** if they are incorrect it asserts.
+*/
+static struct MemBlockHdr *sqlite3MemsysGetHeader(void *pAllocation){
+ struct MemBlockHdr *p;
+ int *pInt;
+ u8 *pU8;
+ int nReserve;
+
+ p = (struct MemBlockHdr*)pAllocation;
+ p--;
+ assert( p->iForeGuard==(int)FOREGUARD );
+ nReserve = ROUND8(p->iSize);
+ pInt = (int*)pAllocation;
+ pU8 = (u8*)pAllocation;
+ assert( pInt[nReserve/sizeof(int)]==(int)REARGUARD );
+ /* This checks any of the "extra" bytes allocated due
+ ** to rounding up to an 8 byte boundary to ensure
+ ** they haven't been overwritten.
+ */
+ while( nReserve-- > p->iSize ) assert( pU8[nReserve]==0x65 );
+ return p;
+}
+
+/*
+** Return the number of bytes currently allocated at address p.
+*/
+static int sqlite3MemSize(void *p){
+ struct MemBlockHdr *pHdr;
+ if( !p ){
+ return 0;
+ }
+ pHdr = sqlite3MemsysGetHeader(p);
+ return (int)pHdr->iSize;
+}
+
+/*
+** Initialize the memory allocation subsystem.
+*/
+static int sqlite3MemInit(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ assert( (sizeof(struct MemBlockHdr)&7) == 0 );
+ if( !sqlite3GlobalConfig.bMemstat ){
+ /* If memory status is enabled, then the malloc.c wrapper will already
+ ** hold the STATIC_MEM mutex when the routines here are invoked. */
+ mem.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize the memory allocation subsystem.
+*/
+static void sqlite3MemShutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ mem.mutex = 0;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int sqlite3MemRoundup(int n){
+ return ROUND8(n);
+}
+
+/*
+** Fill a buffer with pseudo-random bytes. This is used to preset
+** the content of a new memory allocation to unpredictable values and
+** to clear the content of a freed allocation to unpredictable values.
+*/
+static void randomFill(char *pBuf, int nByte){
+ unsigned int x, y, r;
+ x = SQLITE_PTR_TO_INT(pBuf);
+ y = nByte | 1;
+ while( nByte >= 4 ){
+ x = (x>>1) ^ (-(int)(x&1) & 0xd0000001);
+ y = y*1103515245 + 12345;
+ r = x ^ y;
+ *(int*)pBuf = r;
+ pBuf += 4;
+ nByte -= 4;
+ }
+ while( nByte-- > 0 ){
+ x = (x>>1) ^ (-(int)(x&1) & 0xd0000001);
+ y = y*1103515245 + 12345;
+ r = x ^ y;
+ *(pBuf++) = r & 0xff;
+ }
+}
+
+/*
+** Allocate nByte bytes of memory.
+*/
+static void *sqlite3MemMalloc(int nByte){
+ struct MemBlockHdr *pHdr;
+ void **pBt;
+ char *z;
+ int *pInt;
+ void *p = 0;
+ int totalSize;
+ int nReserve;
+ sqlite3_mutex_enter(mem.mutex);
+ assert( mem.disallow==0 );
+ nReserve = ROUND8(nByte);
+ totalSize = nReserve + sizeof(*pHdr) + sizeof(int) +
+ mem.nBacktrace*sizeof(void*) + mem.nTitle;
+ p = malloc(totalSize);
+ if( p ){
+ z = p;
+ pBt = (void**)&z[mem.nTitle];
+ pHdr = (struct MemBlockHdr*)&pBt[mem.nBacktrace];
+ pHdr->pNext = 0;
+ pHdr->pPrev = mem.pLast;
+ if( mem.pLast ){
+ mem.pLast->pNext = pHdr;
+ }else{
+ mem.pFirst = pHdr;
+ }
+ mem.pLast = pHdr;
+ pHdr->iForeGuard = FOREGUARD;
+ pHdr->eType = MEMTYPE_HEAP;
+ pHdr->nBacktraceSlots = mem.nBacktrace;
+ pHdr->nTitle = mem.nTitle;
+ if( mem.nBacktrace ){
+ void *aAddr[40];
+ pHdr->nBacktrace = backtrace(aAddr, mem.nBacktrace+1)-1;
+ memcpy(pBt, &aAddr[1], pHdr->nBacktrace*sizeof(void*));
+ assert(pBt[0]);
+ if( mem.xBacktrace ){
+ mem.xBacktrace(nByte, pHdr->nBacktrace-1, &aAddr[1]);
+ }
+ }else{
+ pHdr->nBacktrace = 0;
+ }
+ if( mem.nTitle ){
+ memcpy(z, mem.zTitle, mem.nTitle);
+ }
+ pHdr->iSize = nByte;
+ adjustStats(nByte, +1);
+ pInt = (int*)&pHdr[1];
+ pInt[nReserve/sizeof(int)] = REARGUARD;
+ randomFill((char*)pInt, nByte);
+ memset(((char*)pInt)+nByte, 0x65, nReserve-nByte);
+ p = (void*)pInt;
+ }
+ sqlite3_mutex_leave(mem.mutex);
+ return p;
+}
+
+/*
+** Free memory.
+*/
+static void sqlite3MemFree(void *pPrior){
+ struct MemBlockHdr *pHdr;
+ void **pBt;
+ char *z;
+ assert( sqlite3GlobalConfig.bMemstat || sqlite3GlobalConfig.bCoreMutex==0
+ || mem.mutex!=0 );
+ pHdr = sqlite3MemsysGetHeader(pPrior);
+ pBt = (void**)pHdr;
+ pBt -= pHdr->nBacktraceSlots;
+ sqlite3_mutex_enter(mem.mutex);
+ if( pHdr->pPrev ){
+ assert( pHdr->pPrev->pNext==pHdr );
+ pHdr->pPrev->pNext = pHdr->pNext;
+ }else{
+ assert( mem.pFirst==pHdr );
+ mem.pFirst = pHdr->pNext;
+ }
+ if( pHdr->pNext ){
+ assert( pHdr->pNext->pPrev==pHdr );
+ pHdr->pNext->pPrev = pHdr->pPrev;
+ }else{
+ assert( mem.pLast==pHdr );
+ mem.pLast = pHdr->pPrev;
+ }
+ z = (char*)pBt;
+ z -= pHdr->nTitle;
+ adjustStats((int)pHdr->iSize, -1);
+ randomFill(z, sizeof(void*)*pHdr->nBacktraceSlots + sizeof(*pHdr) +
+ (int)pHdr->iSize + sizeof(int) + pHdr->nTitle);
+ free(z);
+ sqlite3_mutex_leave(mem.mutex);
+}
+
+/*
+** Change the size of an existing memory allocation.
+**
+** For this debugging implementation, we *always* make a copy of the
+** allocation into a new place in memory. In this way, if the
+** higher level code is using pointer to the old allocation, it is
+** much more likely to break and we are much more liking to find
+** the error.
+*/
+static void *sqlite3MemRealloc(void *pPrior, int nByte){
+ struct MemBlockHdr *pOldHdr;
+ void *pNew;
+ assert( mem.disallow==0 );
+ assert( (nByte & 7)==0 ); /* EV: R-46199-30249 */
+ pOldHdr = sqlite3MemsysGetHeader(pPrior);
+ pNew = sqlite3MemMalloc(nByte);
+ if( pNew ){
+ memcpy(pNew, pPrior, (int)(nByteiSize ? nByte : pOldHdr->iSize));
+ if( nByte>pOldHdr->iSize ){
+ randomFill(&((char*)pNew)[pOldHdr->iSize], nByte - (int)pOldHdr->iSize);
+ }
+ sqlite3MemFree(pPrior);
+ }
+ return pNew;
+}
+
+/*
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file.
+*/
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ static const sqlite3_mem_methods defaultMethods = {
+ sqlite3MemMalloc,
+ sqlite3MemFree,
+ sqlite3MemRealloc,
+ sqlite3MemSize,
+ sqlite3MemRoundup,
+ sqlite3MemInit,
+ sqlite3MemShutdown,
+ 0
+ };
+ sqlite3_config(SQLITE_CONFIG_MALLOC, &defaultMethods);
+}
+
+/*
+** Set the "type" of an allocation.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugSetType(void *p, u8 eType){
+ if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+ struct MemBlockHdr *pHdr;
+ pHdr = sqlite3MemsysGetHeader(p);
+ assert( pHdr->iForeGuard==FOREGUARD );
+ pHdr->eType = eType;
+ }
+}
+
+/*
+** Return TRUE if the mask of type in eType matches the type of the
+** allocation p. Also return true if p==NULL.
+**
+** This routine is designed for use within an assert() statement, to
+** verify the type of an allocation. For example:
+**
+** assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+*/
+SQLITE_PRIVATE int sqlite3MemdebugHasType(void *p, u8 eType){
+ int rc = 1;
+ if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+ struct MemBlockHdr *pHdr;
+ pHdr = sqlite3MemsysGetHeader(p);
+ assert( pHdr->iForeGuard==FOREGUARD ); /* Allocation is valid */
+ if( (pHdr->eType&eType)==0 ){
+ rc = 0;
+ }
+ }
+ return rc;
+}
+
+/*
+** Return TRUE if the mask of type in eType matches no bits of the type of the
+** allocation p. Also return true if p==NULL.
+**
+** This routine is designed for use within an assert() statement, to
+** verify the type of an allocation. For example:
+**
+** assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
+*/
+SQLITE_PRIVATE int sqlite3MemdebugNoType(void *p, u8 eType){
+ int rc = 1;
+ if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+ struct MemBlockHdr *pHdr;
+ pHdr = sqlite3MemsysGetHeader(p);
+ assert( pHdr->iForeGuard==FOREGUARD ); /* Allocation is valid */
+ if( (pHdr->eType&eType)!=0 ){
+ rc = 0;
+ }
+ }
+ return rc;
+}
+
+/*
+** Set the number of backtrace levels kept for each allocation.
+** A value of zero turns off backtracing. The number is always rounded
+** up to a multiple of 2.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugBacktrace(int depth){
+ if( depth<0 ){ depth = 0; }
+ if( depth>20 ){ depth = 20; }
+ depth = (depth+1)&0xfe;
+ mem.nBacktrace = depth;
+}
+
+SQLITE_PRIVATE void sqlite3MemdebugBacktraceCallback(void (*xBacktrace)(int, int, void **)){
+ mem.xBacktrace = xBacktrace;
+}
+
+/*
+** Set the title string for subsequent allocations.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugSettitle(const char *zTitle){
+ unsigned int n = sqlite3Strlen30(zTitle) + 1;
+ sqlite3_mutex_enter(mem.mutex);
+ if( n>=sizeof(mem.zTitle) ) n = sizeof(mem.zTitle)-1;
+ memcpy(mem.zTitle, zTitle, n);
+ mem.zTitle[n] = 0;
+ mem.nTitle = ROUND8(n);
+ sqlite3_mutex_leave(mem.mutex);
+}
+
+SQLITE_PRIVATE void sqlite3MemdebugSync(){
+ struct MemBlockHdr *pHdr;
+ for(pHdr=mem.pFirst; pHdr; pHdr=pHdr->pNext){
+ void **pBt = (void**)pHdr;
+ pBt -= pHdr->nBacktraceSlots;
+ mem.xBacktrace((int)pHdr->iSize, pHdr->nBacktrace-1, &pBt[1]);
+ }
+}
+
+/*
+** Open the file indicated and write a log of all unfreed memory
+** allocations into that log.
+*/
+SQLITE_PRIVATE void sqlite3MemdebugDump(const char *zFilename){
+ FILE *out;
+ struct MemBlockHdr *pHdr;
+ void **pBt;
+ int i;
+ out = fopen(zFilename, "w");
+ if( out==0 ){
+ fprintf(stderr, "** Unable to output memory debug output log: %s **\n",
+ zFilename);
+ return;
+ }
+ for(pHdr=mem.pFirst; pHdr; pHdr=pHdr->pNext){
+ char *z = (char*)pHdr;
+ z -= pHdr->nBacktraceSlots*sizeof(void*) + pHdr->nTitle;
+ fprintf(out, "**** %lld bytes at %p from %s ****\n",
+ pHdr->iSize, &pHdr[1], pHdr->nTitle ? z : "???");
+ if( pHdr->nBacktrace ){
+ fflush(out);
+ pBt = (void**)pHdr;
+ pBt -= pHdr->nBacktraceSlots;
+ backtrace_symbols_fd(pBt, pHdr->nBacktrace, fileno(out));
+ fprintf(out, "\n");
+ }
+ }
+ fprintf(out, "COUNTS:\n");
+ for(i=0; i=1 );
+ size = mem3.aPool[i-1].u.hdr.size4x/4;
+ assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
+ assert( size>=2 );
+ if( size <= MX_SMALL ){
+ memsys3UnlinkFromList(i, &mem3.aiSmall[size-2]);
+ }else{
+ hash = size % N_HASH;
+ memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
+ }
+}
+
+/*
+** Link the chunk at mem3.aPool[i] so that is on the list rooted
+** at *pRoot.
+*/
+static void memsys3LinkIntoList(u32 i, u32 *pRoot){
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ mem3.aPool[i].u.list.next = *pRoot;
+ mem3.aPool[i].u.list.prev = 0;
+ if( *pRoot ){
+ mem3.aPool[*pRoot].u.list.prev = i;
+ }
+ *pRoot = i;
+}
+
+/*
+** Link the chunk at index i into either the appropriate
+** small chunk list, or into the large chunk hash table.
+*/
+static void memsys3Link(u32 i){
+ u32 size, hash;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( i>=1 );
+ assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 );
+ size = mem3.aPool[i-1].u.hdr.size4x/4;
+ assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
+ assert( size>=2 );
+ if( size <= MX_SMALL ){
+ memsys3LinkIntoList(i, &mem3.aiSmall[size-2]);
+ }else{
+ hash = size % N_HASH;
+ memsys3LinkIntoList(i, &mem3.aiHash[hash]);
+ }
+}
+
+/*
+** If the STATIC_MEM mutex is not already held, obtain it now. The mutex
+** will already be held (obtained by code in malloc.c) if
+** sqlite3GlobalConfig.bMemStat is true.
+*/
+static void memsys3Enter(void){
+ if( sqlite3GlobalConfig.bMemstat==0 && mem3.mutex==0 ){
+ mem3.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ }
+ sqlite3_mutex_enter(mem3.mutex);
+}
+static void memsys3Leave(void){
+ sqlite3_mutex_leave(mem3.mutex);
+}
+
+/*
+** Called when we are unable to satisfy an allocation of nBytes.
+*/
+static void memsys3OutOfMemory(int nByte){
+ if( !mem3.alarmBusy ){
+ mem3.alarmBusy = 1;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ sqlite3_mutex_leave(mem3.mutex);
+ sqlite3_release_memory(nByte);
+ sqlite3_mutex_enter(mem3.mutex);
+ mem3.alarmBusy = 0;
+ }
+}
+
+
+/*
+** Chunk i is a free chunk that has been unlinked. Adjust its
+** size parameters for check-out and return a pointer to the
+** user portion of the chunk.
+*/
+static void *memsys3Checkout(u32 i, u32 nBlock){
+ u32 x;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( i>=1 );
+ assert( mem3.aPool[i-1].u.hdr.size4x/4==nBlock );
+ assert( mem3.aPool[i+nBlock-1].u.hdr.prevSize==nBlock );
+ x = mem3.aPool[i-1].u.hdr.size4x;
+ mem3.aPool[i-1].u.hdr.size4x = nBlock*4 | 1 | (x&2);
+ mem3.aPool[i+nBlock-1].u.hdr.prevSize = nBlock;
+ mem3.aPool[i+nBlock-1].u.hdr.size4x |= 2;
+ return &mem3.aPool[i];
+}
+
+/*
+** Carve a piece off of the end of the mem3.iMaster free chunk.
+** Return a pointer to the new allocation. Or, if the master chunk
+** is not large enough, return 0.
+*/
+static void *memsys3FromMaster(u32 nBlock){
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( mem3.szMaster>=nBlock );
+ if( nBlock>=mem3.szMaster-1 ){
+ /* Use the entire master */
+ void *p = memsys3Checkout(mem3.iMaster, mem3.szMaster);
+ mem3.iMaster = 0;
+ mem3.szMaster = 0;
+ mem3.mnMaster = 0;
+ return p;
+ }else{
+ /* Split the master block. Return the tail. */
+ u32 newi, x;
+ newi = mem3.iMaster + mem3.szMaster - nBlock;
+ assert( newi > mem3.iMaster+1 );
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = nBlock;
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x |= 2;
+ mem3.aPool[newi-1].u.hdr.size4x = nBlock*4 + 1;
+ mem3.szMaster -= nBlock;
+ mem3.aPool[newi-1].u.hdr.prevSize = mem3.szMaster;
+ x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+ mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+ if( mem3.szMaster < mem3.mnMaster ){
+ mem3.mnMaster = mem3.szMaster;
+ }
+ return (void*)&mem3.aPool[newi];
+ }
+}
+
+/*
+** *pRoot is the head of a list of free chunks of the same size
+** or same size hash. In other words, *pRoot is an entry in either
+** mem3.aiSmall[] or mem3.aiHash[].
+**
+** This routine examines all entries on the given list and tries
+** to coalesce each entries with adjacent free chunks.
+**
+** If it sees a chunk that is larger than mem3.iMaster, it replaces
+** the current mem3.iMaster with the new larger chunk. In order for
+** this mem3.iMaster replacement to work, the master chunk must be
+** linked into the hash tables. That is not the normal state of
+** affairs, of course. The calling routine must link the master
+** chunk before invoking this routine, then must unlink the (possibly
+** changed) master chunk once this routine has finished.
+*/
+static void memsys3Merge(u32 *pRoot){
+ u32 iNext, prev, size, i, x;
+
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ for(i=*pRoot; i>0; i=iNext){
+ iNext = mem3.aPool[i].u.list.next;
+ size = mem3.aPool[i-1].u.hdr.size4x;
+ assert( (size&1)==0 );
+ if( (size&2)==0 ){
+ memsys3UnlinkFromList(i, pRoot);
+ assert( i > mem3.aPool[i-1].u.hdr.prevSize );
+ prev = i - mem3.aPool[i-1].u.hdr.prevSize;
+ if( prev==iNext ){
+ iNext = mem3.aPool[prev].u.list.next;
+ }
+ memsys3Unlink(prev);
+ size = i + size/4 - prev;
+ x = mem3.aPool[prev-1].u.hdr.size4x & 2;
+ mem3.aPool[prev-1].u.hdr.size4x = size*4 | x;
+ mem3.aPool[prev+size-1].u.hdr.prevSize = size;
+ memsys3Link(prev);
+ i = prev;
+ }else{
+ size /= 4;
+ }
+ if( size>mem3.szMaster ){
+ mem3.iMaster = i;
+ mem3.szMaster = size;
+ }
+ }
+}
+
+/*
+** Return a block of memory of at least nBytes in size.
+** Return NULL if unable.
+**
+** This function assumes that the necessary mutexes, if any, are
+** already held by the caller. Hence "Unsafe".
+*/
+static void *memsys3MallocUnsafe(int nByte){
+ u32 i;
+ u32 nBlock;
+ u32 toFree;
+
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( sizeof(Mem3Block)==8 );
+ if( nByte<=12 ){
+ nBlock = 2;
+ }else{
+ nBlock = (nByte + 11)/8;
+ }
+ assert( nBlock>=2 );
+
+ /* STEP 1:
+ ** Look for an entry of the correct size in either the small
+ ** chunk table or in the large chunk hash table. This is
+ ** successful most of the time (about 9 times out of 10).
+ */
+ if( nBlock <= MX_SMALL ){
+ i = mem3.aiSmall[nBlock-2];
+ if( i>0 ){
+ memsys3UnlinkFromList(i, &mem3.aiSmall[nBlock-2]);
+ return memsys3Checkout(i, nBlock);
+ }
+ }else{
+ int hash = nBlock % N_HASH;
+ for(i=mem3.aiHash[hash]; i>0; i=mem3.aPool[i].u.list.next){
+ if( mem3.aPool[i-1].u.hdr.size4x/4==nBlock ){
+ memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
+ return memsys3Checkout(i, nBlock);
+ }
+ }
+ }
+
+ /* STEP 2:
+ ** Try to satisfy the allocation by carving a piece off of the end
+ ** of the master chunk. This step usually works if step 1 fails.
+ */
+ if( mem3.szMaster>=nBlock ){
+ return memsys3FromMaster(nBlock);
+ }
+
+
+ /* STEP 3:
+ ** Loop through the entire memory pool. Coalesce adjacent free
+ ** chunks. Recompute the master chunk as the largest free chunk.
+ ** Then try again to satisfy the allocation by carving a piece off
+ ** of the end of the master chunk. This step happens very
+ ** rarely (we hope!)
+ */
+ for(toFree=nBlock*16; toFree<(mem3.nPool*16); toFree *= 2){
+ memsys3OutOfMemory(toFree);
+ if( mem3.iMaster ){
+ memsys3Link(mem3.iMaster);
+ mem3.iMaster = 0;
+ mem3.szMaster = 0;
+ }
+ for(i=0; i=nBlock ){
+ return memsys3FromMaster(nBlock);
+ }
+ }
+ }
+
+ /* If none of the above worked, then we fail. */
+ return 0;
+}
+
+/*
+** Free an outstanding memory allocation.
+**
+** This function assumes that the necessary mutexes, if any, are
+** already held by the caller. Hence "Unsafe".
+*/
+static void memsys3FreeUnsafe(void *pOld){
+ Mem3Block *p = (Mem3Block*)pOld;
+ int i;
+ u32 size, x;
+ assert( sqlite3_mutex_held(mem3.mutex) );
+ assert( p>mem3.aPool && p<&mem3.aPool[mem3.nPool] );
+ i = p - mem3.aPool;
+ assert( (mem3.aPool[i-1].u.hdr.size4x&1)==1 );
+ size = mem3.aPool[i-1].u.hdr.size4x/4;
+ assert( i+size<=mem3.nPool+1 );
+ mem3.aPool[i-1].u.hdr.size4x &= ~1;
+ mem3.aPool[i+size-1].u.hdr.prevSize = size;
+ mem3.aPool[i+size-1].u.hdr.size4x &= ~2;
+ memsys3Link(i);
+
+ /* Try to expand the master using the newly freed chunk */
+ if( mem3.iMaster ){
+ while( (mem3.aPool[mem3.iMaster-1].u.hdr.size4x&2)==0 ){
+ size = mem3.aPool[mem3.iMaster-1].u.hdr.prevSize;
+ mem3.iMaster -= size;
+ mem3.szMaster += size;
+ memsys3Unlink(mem3.iMaster);
+ x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+ mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
+ }
+ x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
+ while( (mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x&1)==0 ){
+ memsys3Unlink(mem3.iMaster+mem3.szMaster);
+ mem3.szMaster += mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x/4;
+ mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
+ mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
+ }
+ }
+}
+
+/*
+** Return the size of an outstanding allocation, in bytes. The
+** size returned omits the 8-byte header overhead. This only
+** works for chunks that are currently checked out.
+*/
+static int memsys3Size(void *p){
+ Mem3Block *pBlock;
+ if( p==0 ) return 0;
+ pBlock = (Mem3Block*)p;
+ assert( (pBlock[-1].u.hdr.size4x&1)!=0 );
+ return (pBlock[-1].u.hdr.size4x&~3)*2 - 4;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int memsys3Roundup(int n){
+ if( n<=12 ){
+ return 12;
+ }else{
+ return ((n+11)&~7) - 4;
+ }
+}
+
+/*
+** Allocate nBytes of memory.
+*/
+static void *memsys3Malloc(int nBytes){
+ sqlite3_int64 *p;
+ assert( nBytes>0 ); /* malloc.c filters out 0 byte requests */
+ memsys3Enter();
+ p = memsys3MallocUnsafe(nBytes);
+ memsys3Leave();
+ return (void*)p;
+}
+
+/*
+** Free memory.
+*/
+static void memsys3Free(void *pPrior){
+ assert( pPrior );
+ memsys3Enter();
+ memsys3FreeUnsafe(pPrior);
+ memsys3Leave();
+}
+
+/*
+** Change the size of an existing memory allocation
+*/
+static void *memsys3Realloc(void *pPrior, int nBytes){
+ int nOld;
+ void *p;
+ if( pPrior==0 ){
+ return sqlite3_malloc(nBytes);
+ }
+ if( nBytes<=0 ){
+ sqlite3_free(pPrior);
+ return 0;
+ }
+ nOld = memsys3Size(pPrior);
+ if( nBytes<=nOld && nBytes>=nOld-128 ){
+ return pPrior;
+ }
+ memsys3Enter();
+ p = memsys3MallocUnsafe(nBytes);
+ if( p ){
+ if( nOld>1)!=(size&1) ){
+ fprintf(out, "%p tail checkout bit is incorrect\n", &mem3.aPool[i]);
+ assert( 0 );
+ break;
+ }
+ if( size&1 ){
+ fprintf(out, "%p %6d bytes checked out\n", &mem3.aPool[i], (size/4)*8-8);
+ }else{
+ fprintf(out, "%p %6d bytes free%s\n", &mem3.aPool[i], (size/4)*8-8,
+ i==mem3.iMaster ? " **master**" : "");
+ }
+ }
+ for(i=0; i0; j=mem3.aPool[j].u.list.next){
+ fprintf(out, " %p(%d)", &mem3.aPool[j],
+ (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
+ }
+ fprintf(out, "\n");
+ }
+ for(i=0; i0; j=mem3.aPool[j].u.list.next){
+ fprintf(out, " %p(%d)", &mem3.aPool[j],
+ (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
+ }
+ fprintf(out, "\n");
+ }
+ fprintf(out, "master=%d\n", mem3.iMaster);
+ fprintf(out, "nowUsed=%d\n", mem3.nPool*8 - mem3.szMaster*8);
+ fprintf(out, "mxUsed=%d\n", mem3.nPool*8 - mem3.mnMaster*8);
+ sqlite3_mutex_leave(mem3.mutex);
+ if( out==stdout ){
+ fflush(stdout);
+ }else{
+ fclose(out);
+ }
+#else
+ UNUSED_PARAMETER(zFilename);
+#endif
+}
+
+/*
+** This routine is the only routine in this file with external
+** linkage.
+**
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file. The
+** arguments specify the block of memory to manage.
+**
+** This routine is only called by sqlite3_config(), and therefore
+** is not required to be threadsafe (it is not).
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys3(void){
+ static const sqlite3_mem_methods mempoolMethods = {
+ memsys3Malloc,
+ memsys3Free,
+ memsys3Realloc,
+ memsys3Size,
+ memsys3Roundup,
+ memsys3Init,
+ memsys3Shutdown,
+ 0
+ };
+ return &mempoolMethods;
+}
+
+#endif /* SQLITE_ENABLE_MEMSYS3 */
+
+/************** End of mem3.c ************************************************/
+/************** Begin file mem5.c ********************************************/
+/*
+** 2007 October 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement a memory
+** allocation subsystem for use by SQLite.
+**
+** This version of the memory allocation subsystem omits all
+** use of malloc(). The application gives SQLite a block of memory
+** before calling sqlite3_initialize() from which allocations
+** are made and returned by the xMalloc() and xRealloc()
+** implementations. Once sqlite3_initialize() has been called,
+** the amount of memory available to SQLite is fixed and cannot
+** be changed.
+**
+** This version of the memory allocation subsystem is included
+** in the build only if SQLITE_ENABLE_MEMSYS5 is defined.
+**
+** This memory allocator uses the following algorithm:
+**
+** 1. All memory allocations sizes are rounded up to a power of 2.
+**
+** 2. If two adjacent free blocks are the halves of a larger block,
+** then the two blocks are coalesed into the single larger block.
+**
+** 3. New memory is allocated from the first available free block.
+**
+** This algorithm is described in: J. M. Robson. "Bounds for Some Functions
+** Concerning Dynamic Storage Allocation". Journal of the Association for
+** Computing Machinery, Volume 21, Number 8, July 1974, pages 491-499.
+**
+** Let n be the size of the largest allocation divided by the minimum
+** allocation size (after rounding all sizes up to a power of 2.) Let M
+** be the maximum amount of memory ever outstanding at one time. Let
+** N be the total amount of memory available for allocation. Robson
+** proved that this memory allocator will never breakdown due to
+** fragmentation as long as the following constraint holds:
+**
+** N >= M*(1 + log2(n)/2) - n + 1
+**
+** The sqlite3_status() logic tracks the maximum values of n and M so
+** that an application can, at any time, verify this constraint.
+*/
+
+/*
+** This version of the memory allocator is used only when
+** SQLITE_ENABLE_MEMSYS5 is defined.
+*/
+#ifdef SQLITE_ENABLE_MEMSYS5
+
+/*
+** A minimum allocation is an instance of the following structure.
+** Larger allocations are an array of these structures where the
+** size of the array is a power of 2.
+**
+** The size of this object must be a power of two. That fact is
+** verified in memsys5Init().
+*/
+typedef struct Mem5Link Mem5Link;
+struct Mem5Link {
+ int next; /* Index of next free chunk */
+ int prev; /* Index of previous free chunk */
+};
+
+/*
+** Maximum size of any allocation is ((1<=0 && i=0 && iLogsize<=LOGMAX );
+ assert( (mem5.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
+
+ next = MEM5LINK(i)->next;
+ prev = MEM5LINK(i)->prev;
+ if( prev<0 ){
+ mem5.aiFreelist[iLogsize] = next;
+ }else{
+ MEM5LINK(prev)->next = next;
+ }
+ if( next>=0 ){
+ MEM5LINK(next)->prev = prev;
+ }
+}
+
+/*
+** Link the chunk at mem5.aPool[i] so that is on the iLogsize
+** free list.
+*/
+static void memsys5Link(int i, int iLogsize){
+ int x;
+ assert( sqlite3_mutex_held(mem5.mutex) );
+ assert( i>=0 && i=0 && iLogsize<=LOGMAX );
+ assert( (mem5.aCtrl[i] & CTRL_LOGSIZE)==iLogsize );
+
+ x = MEM5LINK(i)->next = mem5.aiFreelist[iLogsize];
+ MEM5LINK(i)->prev = -1;
+ if( x>=0 ){
+ assert( xprev = i;
+ }
+ mem5.aiFreelist[iLogsize] = i;
+}
+
+/*
+** If the STATIC_MEM mutex is not already held, obtain it now. The mutex
+** will already be held (obtained by code in malloc.c) if
+** sqlite3GlobalConfig.bMemStat is true.
+*/
+static void memsys5Enter(void){
+ sqlite3_mutex_enter(mem5.mutex);
+}
+static void memsys5Leave(void){
+ sqlite3_mutex_leave(mem5.mutex);
+}
+
+/*
+** Return the size of an outstanding allocation, in bytes. The
+** size returned omits the 8-byte header overhead. This only
+** works for chunks that are currently checked out.
+*/
+static int memsys5Size(void *p){
+ int iSize = 0;
+ if( p ){
+ int i = (int)(((u8 *)p-mem5.zPool)/mem5.szAtom);
+ assert( i>=0 && i0 );
+
+ /* Keep track of the maximum allocation request. Even unfulfilled
+ ** requests are counted */
+ if( (u32)nByte>mem5.maxRequest ){
+ mem5.maxRequest = nByte;
+ }
+
+ /* Abort if the requested allocation size is larger than the largest
+ ** power of two that we can represent using 32-bit signed integers.
+ */
+ if( nByte > 0x40000000 ){
+ return 0;
+ }
+
+ /* Round nByte up to the next valid power of two */
+ for(iFullSz=mem5.szAtom, iLogsize=0; iFullSzLOGMAX ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes", nByte);
+ return 0;
+ }
+ i = mem5.aiFreelist[iBin];
+ memsys5Unlink(i, iBin);
+ while( iBin>iLogsize ){
+ int newSize;
+
+ iBin--;
+ newSize = 1 << iBin;
+ mem5.aCtrl[i+newSize] = CTRL_FREE | iBin;
+ memsys5Link(i+newSize, iBin);
+ }
+ mem5.aCtrl[i] = iLogsize;
+
+ /* Update allocator performance statistics. */
+ mem5.nAlloc++;
+ mem5.totalAlloc += iFullSz;
+ mem5.totalExcess += iFullSz - nByte;
+ mem5.currentCount++;
+ mem5.currentOut += iFullSz;
+ if( mem5.maxCount=0 && iBlock0 );
+ assert( mem5.currentOut>=(size*mem5.szAtom) );
+ mem5.currentCount--;
+ mem5.currentOut -= size*mem5.szAtom;
+ assert( mem5.currentOut>0 || mem5.currentCount==0 );
+ assert( mem5.currentCount>0 || mem5.currentOut==0 );
+
+ mem5.aCtrl[iBlock] = CTRL_FREE | iLogsize;
+ while( ALWAYS(iLogsize>iLogsize) & 1 ){
+ iBuddy = iBlock - size;
+ }else{
+ iBuddy = iBlock + size;
+ }
+ assert( iBuddy>=0 );
+ if( (iBuddy+(1<mem5.nBlock ) break;
+ if( mem5.aCtrl[iBuddy]!=(CTRL_FREE | iLogsize) ) break;
+ memsys5Unlink(iBuddy, iLogsize);
+ iLogsize++;
+ if( iBuddy0 ){
+ memsys5Enter();
+ p = memsys5MallocUnsafe(nBytes);
+ memsys5Leave();
+ }
+ return (void*)p;
+}
+
+/*
+** Free memory.
+**
+** The outer layer memory allocator prevents this routine from
+** being called with pPrior==0.
+*/
+static void memsys5Free(void *pPrior){
+ assert( pPrior!=0 );
+ memsys5Enter();
+ memsys5FreeUnsafe(pPrior);
+ memsys5Leave();
+}
+
+/*
+** Change the size of an existing memory allocation.
+**
+** The outer layer memory allocator prevents this routine from
+** being called with pPrior==0.
+**
+** nBytes is always a value obtained from a prior call to
+** memsys5Round(). Hence nBytes is always a non-negative power
+** of two. If nBytes==0 that means that an oversize allocation
+** (an allocation larger than 0x40000000) was requested and this
+** routine should return 0 without freeing pPrior.
+*/
+static void *memsys5Realloc(void *pPrior, int nBytes){
+ int nOld;
+ void *p;
+ assert( pPrior!=0 );
+ assert( (nBytes&(nBytes-1))==0 ); /* EV: R-46199-30249 */
+ assert( nBytes>=0 );
+ if( nBytes==0 ){
+ return 0;
+ }
+ nOld = memsys5Size(pPrior);
+ if( nBytes<=nOld ){
+ return pPrior;
+ }
+ memsys5Enter();
+ p = memsys5MallocUnsafe(nBytes);
+ if( p ){
+ memcpy(p, pPrior, nOld);
+ memsys5FreeUnsafe(pPrior);
+ }
+ memsys5Leave();
+ return p;
+}
+
+/*
+** Round up a request size to the next valid allocation size. If
+** the allocation is too large to be handled by this allocation system,
+** return 0.
+**
+** All allocations must be a power of two and must be expressed by a
+** 32-bit signed integer. Hence the largest allocation is 0x40000000
+** or 1073741824 bytes.
+*/
+static int memsys5Roundup(int n){
+ int iFullSz;
+ if( n > 0x40000000 ) return 0;
+ for(iFullSz=mem5.szAtom; iFullSz 0
+** memsys5Log(2) -> 1
+** memsys5Log(4) -> 2
+** memsys5Log(5) -> 3
+** memsys5Log(8) -> 3
+** memsys5Log(9) -> 4
+*/
+static int memsys5Log(int iValue){
+ int iLog;
+ for(iLog=0; (iLog<(int)((sizeof(int)*8)-1)) && (1<mem5.szAtom ){
+ mem5.szAtom = mem5.szAtom << 1;
+ }
+
+ mem5.nBlock = (nByte / (mem5.szAtom+sizeof(u8)));
+ mem5.zPool = zByte;
+ mem5.aCtrl = (u8 *)&mem5.zPool[mem5.nBlock*mem5.szAtom];
+
+ for(ii=0; ii<=LOGMAX; ii++){
+ mem5.aiFreelist[ii] = -1;
+ }
+
+ iOffset = 0;
+ for(ii=LOGMAX; ii>=0; ii--){
+ int nAlloc = (1<mem5.nBlock);
+ }
+
+ /* If a mutex is required for normal operation, allocate one */
+ if( sqlite3GlobalConfig.bMemstat==0 ){
+ mem5.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ }
+
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void memsys5Shutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ mem5.mutex = 0;
+ return;
+}
+
+#ifdef SQLITE_TEST
+/*
+** Open the file indicated and write a log of all unfreed memory
+** allocations into that log.
+*/
+SQLITE_PRIVATE void sqlite3Memsys5Dump(const char *zFilename){
+ FILE *out;
+ int i, j, n;
+ int nMinLog;
+
+ if( zFilename==0 || zFilename[0]==0 ){
+ out = stdout;
+ }else{
+ out = fopen(zFilename, "w");
+ if( out==0 ){
+ fprintf(stderr, "** Unable to output memory debug output log: %s **\n",
+ zFilename);
+ return;
+ }
+ }
+ memsys5Enter();
+ nMinLog = memsys5Log(mem5.szAtom);
+ for(i=0; i<=LOGMAX && i+nMinLog<32; i++){
+ for(n=0, j=mem5.aiFreelist[i]; j>=0; j = MEM5LINK(j)->next, n++){}
+ fprintf(out, "freelist items of size %d: %d\n", mem5.szAtom << i, n);
+ }
+ fprintf(out, "mem5.nAlloc = %llu\n", mem5.nAlloc);
+ fprintf(out, "mem5.totalAlloc = %llu\n", mem5.totalAlloc);
+ fprintf(out, "mem5.totalExcess = %llu\n", mem5.totalExcess);
+ fprintf(out, "mem5.currentOut = %u\n", mem5.currentOut);
+ fprintf(out, "mem5.currentCount = %u\n", mem5.currentCount);
+ fprintf(out, "mem5.maxOut = %u\n", mem5.maxOut);
+ fprintf(out, "mem5.maxCount = %u\n", mem5.maxCount);
+ fprintf(out, "mem5.maxRequest = %u\n", mem5.maxRequest);
+ memsys5Leave();
+ if( out==stdout ){
+ fflush(stdout);
+ }else{
+ fclose(out);
+ }
+}
+#endif
+
+/*
+** This routine is the only routine in this file with external
+** linkage. It returns a pointer to a static sqlite3_mem_methods
+** struct populated with the memsys5 methods.
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void){
+ static const sqlite3_mem_methods memsys5Methods = {
+ memsys5Malloc,
+ memsys5Free,
+ memsys5Realloc,
+ memsys5Size,
+ memsys5Roundup,
+ memsys5Init,
+ memsys5Shutdown,
+ 0
+ };
+ return &memsys5Methods;
+}
+
+#endif /* SQLITE_ENABLE_MEMSYS5 */
+
+/************** End of mem5.c ************************************************/
+/************** Begin file mutex.c *******************************************/
+/*
+** 2007 August 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes.
+**
+** This file contains code that is common across all mutex implementations.
+*/
+
+#if defined(SQLITE_DEBUG) && !defined(SQLITE_MUTEX_OMIT)
+/*
+** For debugging purposes, record when the mutex subsystem is initialized
+** and uninitialized so that we can assert() if there is an attempt to
+** allocate a mutex while the system is uninitialized.
+*/
+static SQLITE_WSD int mutexIsInit = 0;
+#endif /* SQLITE_DEBUG */
+
+
+#ifndef SQLITE_MUTEX_OMIT
+/*
+** Initialize the mutex system.
+*/
+SQLITE_PRIVATE int sqlite3MutexInit(void){
+ int rc = SQLITE_OK;
+ if( !sqlite3GlobalConfig.mutex.xMutexAlloc ){
+ /* If the xMutexAlloc method has not been set, then the user did not
+ ** install a mutex implementation via sqlite3_config() prior to
+ ** sqlite3_initialize() being called. This block copies pointers to
+ ** the default implementation into the sqlite3GlobalConfig structure.
+ */
+ sqlite3_mutex_methods const *pFrom;
+ sqlite3_mutex_methods *pTo = &sqlite3GlobalConfig.mutex;
+
+ if( sqlite3GlobalConfig.bCoreMutex ){
+ pFrom = sqlite3DefaultMutex();
+ }else{
+ pFrom = sqlite3NoopMutex();
+ }
+ memcpy(pTo, pFrom, offsetof(sqlite3_mutex_methods, xMutexAlloc));
+ memcpy(&pTo->xMutexFree, &pFrom->xMutexFree,
+ sizeof(*pTo) - offsetof(sqlite3_mutex_methods, xMutexFree));
+ pTo->xMutexAlloc = pFrom->xMutexAlloc;
+ }
+ rc = sqlite3GlobalConfig.mutex.xMutexInit();
+
+#ifdef SQLITE_DEBUG
+ GLOBAL(int, mutexIsInit) = 1;
+#endif
+
+ return rc;
+}
+
+/*
+** Shutdown the mutex system. This call frees resources allocated by
+** sqlite3MutexInit().
+*/
+SQLITE_PRIVATE int sqlite3MutexEnd(void){
+ int rc = SQLITE_OK;
+ if( sqlite3GlobalConfig.mutex.xMutexEnd ){
+ rc = sqlite3GlobalConfig.mutex.xMutexEnd();
+ }
+
+#ifdef SQLITE_DEBUG
+ GLOBAL(int, mutexIsInit) = 0;
+#endif
+
+ return rc;
+}
+
+/*
+** Retrieve a pointer to a static mutex or allocate a new dynamic one.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int id){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return sqlite3GlobalConfig.mutex.xMutexAlloc(id);
+}
+
+SQLITE_PRIVATE sqlite3_mutex *sqlite3MutexAlloc(int id){
+ if( !sqlite3GlobalConfig.bCoreMutex ){
+ return 0;
+ }
+ assert( GLOBAL(int, mutexIsInit) );
+ return sqlite3GlobalConfig.mutex.xMutexAlloc(id);
+}
+
+/*
+** Free a dynamic mutex.
+*/
+SQLITE_API void sqlite3_mutex_free(sqlite3_mutex *p){
+ if( p ){
+ sqlite3GlobalConfig.mutex.xMutexFree(p);
+ }
+}
+
+/*
+** Obtain the mutex p. If some other thread already has the mutex, block
+** until it can be obtained.
+*/
+SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex *p){
+ if( p ){
+ sqlite3GlobalConfig.mutex.xMutexEnter(p);
+ }
+}
+
+/*
+** Obtain the mutex p. If successful, return SQLITE_OK. Otherwise, if another
+** thread holds the mutex and it cannot be obtained, return SQLITE_BUSY.
+*/
+SQLITE_API int sqlite3_mutex_try(sqlite3_mutex *p){
+ int rc = SQLITE_OK;
+ if( p ){
+ return sqlite3GlobalConfig.mutex.xMutexTry(p);
+ }
+ return rc;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was previously
+** entered by the same thread. The behavior is undefined if the mutex
+** is not currently entered. If a NULL pointer is passed as an argument
+** this function is a no-op.
+*/
+SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex *p){
+ if( p ){
+ sqlite3GlobalConfig.mutex.xMutexLeave(p);
+ }
+}
+
+#ifndef NDEBUG
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use inside assert() statements.
+*/
+SQLITE_API int sqlite3_mutex_held(sqlite3_mutex *p){
+ return p==0 || sqlite3GlobalConfig.mutex.xMutexHeld(p);
+}
+SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
+ return p==0 || sqlite3GlobalConfig.mutex.xMutexNotheld(p);
+}
+#endif
+
+#endif /* !defined(SQLITE_MUTEX_OMIT) */
+
+/************** End of mutex.c ***********************************************/
+/************** Begin file mutex_noop.c **************************************/
+/*
+** 2008 October 07
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes.
+**
+** This implementation in this file does not provide any mutual
+** exclusion and is thus suitable for use only in applications
+** that use SQLite in a single thread. The routines defined
+** here are place-holders. Applications can substitute working
+** mutex routines at start-time using the
+**
+** sqlite3_config(SQLITE_CONFIG_MUTEX,...)
+**
+** interface.
+**
+** If compiled with SQLITE_DEBUG, then additional logic is inserted
+** that does error checking on mutexes to make sure they are being
+** called correctly.
+*/
+
+#ifndef SQLITE_MUTEX_OMIT
+
+#ifndef SQLITE_DEBUG
+/*
+** Stub routines for all mutex methods.
+**
+** This routines provide no mutual exclusion or error checking.
+*/
+static int noopMutexInit(void){ return SQLITE_OK; }
+static int noopMutexEnd(void){ return SQLITE_OK; }
+static sqlite3_mutex *noopMutexAlloc(int id){
+ UNUSED_PARAMETER(id);
+ return (sqlite3_mutex*)8;
+}
+static void noopMutexFree(sqlite3_mutex *p){ UNUSED_PARAMETER(p); return; }
+static void noopMutexEnter(sqlite3_mutex *p){ UNUSED_PARAMETER(p); return; }
+static int noopMutexTry(sqlite3_mutex *p){
+ UNUSED_PARAMETER(p);
+ return SQLITE_OK;
+}
+static void noopMutexLeave(sqlite3_mutex *p){ UNUSED_PARAMETER(p); return; }
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3NoopMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ noopMutexInit,
+ noopMutexEnd,
+ noopMutexAlloc,
+ noopMutexFree,
+ noopMutexEnter,
+ noopMutexTry,
+ noopMutexLeave,
+
+ 0,
+ 0,
+ };
+
+ return &sMutex;
+}
+#endif /* !SQLITE_DEBUG */
+
+#ifdef SQLITE_DEBUG
+/*
+** In this implementation, error checking is provided for testing
+** and debugging purposes. The mutexes still do not provide any
+** mutual exclusion.
+*/
+
+/*
+** The mutex object
+*/
+typedef struct sqlite3_debug_mutex {
+ int id; /* The mutex type */
+ int cnt; /* Number of entries without a matching leave */
+} sqlite3_debug_mutex;
+
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use inside assert() statements.
+*/
+static int debugMutexHeld(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ return p==0 || p->cnt>0;
+}
+static int debugMutexNotheld(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ return p==0 || p->cnt==0;
+}
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int debugMutexInit(void){ return SQLITE_OK; }
+static int debugMutexEnd(void){ return SQLITE_OK; }
+
+/*
+** The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. If it returns NULL
+** that means that a mutex could not be allocated.
+*/
+static sqlite3_mutex *debugMutexAlloc(int id){
+ static sqlite3_debug_mutex aStatic[6];
+ sqlite3_debug_mutex *pNew = 0;
+ switch( id ){
+ case SQLITE_MUTEX_FAST:
+ case SQLITE_MUTEX_RECURSIVE: {
+ pNew = sqlite3Malloc(sizeof(*pNew));
+ if( pNew ){
+ pNew->id = id;
+ pNew->cnt = 0;
+ }
+ break;
+ }
+ default: {
+ assert( id-2 >= 0 );
+ assert( id-2 < (int)(sizeof(aStatic)/sizeof(aStatic[0])) );
+ pNew = &aStatic[id-2];
+ pNew->id = id;
+ break;
+ }
+ }
+ return (sqlite3_mutex*)pNew;
+}
+
+/*
+** This routine deallocates a previously allocated mutex.
+*/
+static void debugMutexFree(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( p->cnt==0 );
+ assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
+ sqlite3_free(p);
+}
+
+/*
+** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
+** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
+** be entered multiple times by the same thread. In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter. If the same thread tries to enter any other kind of mutex
+** more than once, the behavior is undefined.
+*/
+static void debugMutexEnter(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(pX) );
+ p->cnt++;
+}
+static int debugMutexTry(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(pX) );
+ p->cnt++;
+ return SQLITE_OK;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. The behavior
+** is undefined if the mutex is not currently entered or
+** is not currently allocated. SQLite will never do either.
+*/
+static void debugMutexLeave(sqlite3_mutex *pX){
+ sqlite3_debug_mutex *p = (sqlite3_debug_mutex*)pX;
+ assert( debugMutexHeld(pX) );
+ p->cnt--;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(pX) );
+}
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3NoopMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ debugMutexInit,
+ debugMutexEnd,
+ debugMutexAlloc,
+ debugMutexFree,
+ debugMutexEnter,
+ debugMutexTry,
+ debugMutexLeave,
+
+ debugMutexHeld,
+ debugMutexNotheld
+ };
+
+ return &sMutex;
+}
+#endif /* SQLITE_DEBUG */
+
+/*
+** If compiled with SQLITE_MUTEX_NOOP, then the no-op mutex implementation
+** is used regardless of the run-time threadsafety setting.
+*/
+#ifdef SQLITE_MUTEX_NOOP
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
+ return sqlite3NoopMutex();
+}
+#endif /* defined(SQLITE_MUTEX_NOOP) */
+#endif /* !defined(SQLITE_MUTEX_OMIT) */
+
+/************** End of mutex_noop.c ******************************************/
+/************** Begin file mutex_unix.c **************************************/
+/*
+** 2007 August 28
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes for pthreads
+*/
+
+/*
+** The code in this file is only used if we are compiling threadsafe
+** under unix with pthreads.
+**
+** Note that this implementation requires a version of pthreads that
+** supports recursive mutexes.
+*/
+#ifdef SQLITE_MUTEX_PTHREADS
+
+#include
+
+/*
+** The sqlite3_mutex.id, sqlite3_mutex.nRef, and sqlite3_mutex.owner fields
+** are necessary under two condidtions: (1) Debug builds and (2) using
+** home-grown mutexes. Encapsulate these conditions into a single #define.
+*/
+#if defined(SQLITE_DEBUG) || defined(SQLITE_HOMEGROWN_RECURSIVE_MUTEX)
+# define SQLITE_MUTEX_NREF 1
+#else
+# define SQLITE_MUTEX_NREF 0
+#endif
+
+/*
+** Each recursive mutex is an instance of the following structure.
+*/
+struct sqlite3_mutex {
+ pthread_mutex_t mutex; /* Mutex controlling the lock */
+#if SQLITE_MUTEX_NREF
+ int id; /* Mutex type */
+ volatile int nRef; /* Number of entrances */
+ volatile pthread_t owner; /* Thread that is within this mutex */
+ int trace; /* True to trace changes */
+#endif
+};
+#if SQLITE_MUTEX_NREF
+#define SQLITE3_MUTEX_INITIALIZER { PTHREAD_MUTEX_INITIALIZER, 0, 0, (pthread_t)0, 0 }
+#else
+#define SQLITE3_MUTEX_INITIALIZER { PTHREAD_MUTEX_INITIALIZER }
+#endif
+
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use only inside assert() statements. On some platforms,
+** there might be race conditions that can cause these routines to
+** deliver incorrect results. In particular, if pthread_equal() is
+** not an atomic operation, then these routines might delivery
+** incorrect results. On most platforms, pthread_equal() is a
+** comparison of two integers and is therefore atomic. But we are
+** told that HPUX is not such a platform. If so, then these routines
+** will not always work correctly on HPUX.
+**
+** On those platforms where pthread_equal() is not atomic, SQLite
+** should be compiled without -DSQLITE_DEBUG and with -DNDEBUG to
+** make sure no assert() statements are evaluated and hence these
+** routines are never called.
+*/
+#if !defined(NDEBUG) || defined(SQLITE_DEBUG)
+static int pthreadMutexHeld(sqlite3_mutex *p){
+ return (p->nRef!=0 && pthread_equal(p->owner, pthread_self()));
+}
+static int pthreadMutexNotheld(sqlite3_mutex *p){
+ return p->nRef==0 || pthread_equal(p->owner, pthread_self())==0;
+}
+#endif
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static int pthreadMutexInit(void){ return SQLITE_OK; }
+static int pthreadMutexEnd(void){ return SQLITE_OK; }
+
+/*
+** The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. If it returns NULL
+** that means that a mutex could not be allocated. SQLite
+** will unwind its stack and return an error. The argument
+** to sqlite3_mutex_alloc() is one of these integer constants:
+**
+**
+** - SQLITE_MUTEX_FAST
+**
- SQLITE_MUTEX_RECURSIVE
+**
- SQLITE_MUTEX_STATIC_MASTER
+**
- SQLITE_MUTEX_STATIC_MEM
+**
- SQLITE_MUTEX_STATIC_MEM2
+**
- SQLITE_MUTEX_STATIC_PRNG
+**
- SQLITE_MUTEX_STATIC_LRU
+**
- SQLITE_MUTEX_STATIC_PMEM
+**
+**
+** The first two constants cause sqlite3_mutex_alloc() to create
+** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
+** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
+** The mutex implementation does not need to make a distinction
+** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
+** not want to. But SQLite will only request a recursive mutex in
+** cases where it really needs one. If a faster non-recursive mutex
+** implementation is available on the host platform, the mutex subsystem
+** might return such a mutex in response to SQLITE_MUTEX_FAST.
+**
+** The other allowed parameters to sqlite3_mutex_alloc() each return
+** a pointer to a static preexisting mutex. Six static mutexes are
+** used by the current version of SQLite. Future versions of SQLite
+** may add additional static mutexes. Static mutexes are for internal
+** use by SQLite only. Applications that use SQLite mutexes should
+** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
+** SQLITE_MUTEX_RECURSIVE.
+**
+** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
+** returns a different mutex on every call. But for the static
+** mutex types, the same mutex is returned on every call that has
+** the same type number.
+*/
+static sqlite3_mutex *pthreadMutexAlloc(int iType){
+ static sqlite3_mutex staticMutexes[] = {
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER
+ };
+ sqlite3_mutex *p;
+ switch( iType ){
+ case SQLITE_MUTEX_RECURSIVE: {
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ /* If recursive mutexes are not available, we will have to
+ ** build our own. See below. */
+ pthread_mutex_init(&p->mutex, 0);
+#else
+ /* Use a recursive mutex if it is available */
+ pthread_mutexattr_t recursiveAttr;
+ pthread_mutexattr_init(&recursiveAttr);
+ pthread_mutexattr_settype(&recursiveAttr, PTHREAD_MUTEX_RECURSIVE);
+ pthread_mutex_init(&p->mutex, &recursiveAttr);
+ pthread_mutexattr_destroy(&recursiveAttr);
+#endif
+#if SQLITE_MUTEX_NREF
+ p->id = iType;
+#endif
+ }
+ break;
+ }
+ case SQLITE_MUTEX_FAST: {
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+#if SQLITE_MUTEX_NREF
+ p->id = iType;
+#endif
+ pthread_mutex_init(&p->mutex, 0);
+ }
+ break;
+ }
+ default: {
+ assert( iType-2 >= 0 );
+ assert( iType-2 < ArraySize(staticMutexes) );
+ p = &staticMutexes[iType-2];
+#if SQLITE_MUTEX_NREF
+ p->id = iType;
+#endif
+ break;
+ }
+ }
+ return p;
+}
+
+
+/*
+** This routine deallocates a previously
+** allocated mutex. SQLite is careful to deallocate every
+** mutex that it allocates.
+*/
+static void pthreadMutexFree(sqlite3_mutex *p){
+ assert( p->nRef==0 );
+ assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
+ pthread_mutex_destroy(&p->mutex);
+ sqlite3_free(p);
+}
+
+/*
+** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
+** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
+** be entered multiple times by the same thread. In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter. If the same thread tries to enter any other kind of mutex
+** more than once, the behavior is undefined.
+*/
+static void pthreadMutexEnter(sqlite3_mutex *p){
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
+
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ /* If recursive mutexes are not available, then we have to grow
+ ** our own. This implementation assumes that pthread_equal()
+ ** is atomic - that it cannot be deceived into thinking self
+ ** and p->owner are equal if p->owner changes between two values
+ ** that are not equal to self while the comparison is taking place.
+ ** This implementation also assumes a coherent cache - that
+ ** separate processes cannot read different values from the same
+ ** address at the same time. If either of these two conditions
+ ** are not met, then the mutexes will fail and problems will result.
+ */
+ {
+ pthread_t self = pthread_self();
+ if( p->nRef>0 && pthread_equal(p->owner, self) ){
+ p->nRef++;
+ }else{
+ pthread_mutex_lock(&p->mutex);
+ assert( p->nRef==0 );
+ p->owner = self;
+ p->nRef = 1;
+ }
+ }
+#else
+ /* Use the built-in recursive mutexes if they are available.
+ */
+ pthread_mutex_lock(&p->mutex);
+#if SQLITE_MUTEX_NREF
+ assert( p->nRef>0 || p->owner==0 );
+ p->owner = pthread_self();
+ p->nRef++;
+#endif
+#endif
+
+#ifdef SQLITE_DEBUG
+ if( p->trace ){
+ printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+}
+static int pthreadMutexTry(sqlite3_mutex *p){
+ int rc;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || pthreadMutexNotheld(p) );
+
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ /* If recursive mutexes are not available, then we have to grow
+ ** our own. This implementation assumes that pthread_equal()
+ ** is atomic - that it cannot be deceived into thinking self
+ ** and p->owner are equal if p->owner changes between two values
+ ** that are not equal to self while the comparison is taking place.
+ ** This implementation also assumes a coherent cache - that
+ ** separate processes cannot read different values from the same
+ ** address at the same time. If either of these two conditions
+ ** are not met, then the mutexes will fail and problems will result.
+ */
+ {
+ pthread_t self = pthread_self();
+ if( p->nRef>0 && pthread_equal(p->owner, self) ){
+ p->nRef++;
+ rc = SQLITE_OK;
+ }else if( pthread_mutex_trylock(&p->mutex)==0 ){
+ assert( p->nRef==0 );
+ p->owner = self;
+ p->nRef = 1;
+ rc = SQLITE_OK;
+ }else{
+ rc = SQLITE_BUSY;
+ }
+ }
+#else
+ /* Use the built-in recursive mutexes if they are available.
+ */
+ if( pthread_mutex_trylock(&p->mutex)==0 ){
+#if SQLITE_MUTEX_NREF
+ p->owner = pthread_self();
+ p->nRef++;
+#endif
+ rc = SQLITE_OK;
+ }else{
+ rc = SQLITE_BUSY;
+ }
+#endif
+
+#ifdef SQLITE_DEBUG
+ if( rc==SQLITE_OK && p->trace ){
+ printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+ return rc;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. The behavior
+** is undefined if the mutex is not currently entered or
+** is not currently allocated. SQLite will never do either.
+*/
+static void pthreadMutexLeave(sqlite3_mutex *p){
+ assert( pthreadMutexHeld(p) );
+#if SQLITE_MUTEX_NREF
+ p->nRef--;
+ if( p->nRef==0 ) p->owner = 0;
+#endif
+ assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
+
+#ifdef SQLITE_HOMEGROWN_RECURSIVE_MUTEX
+ if( p->nRef==0 ){
+ pthread_mutex_unlock(&p->mutex);
+ }
+#else
+ pthread_mutex_unlock(&p->mutex);
+#endif
+
+#ifdef SQLITE_DEBUG
+ if( p->trace ){
+ printf("leave mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+}
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ pthreadMutexInit,
+ pthreadMutexEnd,
+ pthreadMutexAlloc,
+ pthreadMutexFree,
+ pthreadMutexEnter,
+ pthreadMutexTry,
+ pthreadMutexLeave,
+#ifdef SQLITE_DEBUG
+ pthreadMutexHeld,
+ pthreadMutexNotheld
+#else
+ 0,
+ 0
+#endif
+ };
+
+ return &sMutex;
+}
+
+#endif /* SQLITE_MUTEX_PTHREADS */
+
+/************** End of mutex_unix.c ******************************************/
+/************** Begin file mutex_w32.c ***************************************/
+/*
+** 2007 August 14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains the C functions that implement mutexes for win32
+*/
+
+#if SQLITE_OS_WIN
+/*
+** Include the header file for the Windows VFS.
+*/
+/************** Include os_win.h in the middle of mutex_w32.c ****************/
+/************** Begin file os_win.h ******************************************/
+/*
+** 2013 November 25
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains code that is specific to Windows.
+*/
+#ifndef _OS_WIN_H_
+#define _OS_WIN_H_
+
+/*
+** Include the primary Windows SDK header file.
+*/
+#include "windows.h"
+
+#ifdef __CYGWIN__
+# include
+# include /* amalgamator: dontcache */
+#endif
+
+/*
+** Determine if we are dealing with Windows NT.
+**
+** We ought to be able to determine if we are compiling for Windows 9x or
+** Windows NT using the _WIN32_WINNT macro as follows:
+**
+** #if defined(_WIN32_WINNT)
+** # define SQLITE_OS_WINNT 1
+** #else
+** # define SQLITE_OS_WINNT 0
+** #endif
+**
+** However, Visual Studio 2005 does not set _WIN32_WINNT by default, as
+** it ought to, so the above test does not work. We'll just assume that
+** everything is Windows NT unless the programmer explicitly says otherwise
+** by setting SQLITE_OS_WINNT to 0.
+*/
+#if SQLITE_OS_WIN && !defined(SQLITE_OS_WINNT)
+# define SQLITE_OS_WINNT 1
+#endif
+
+/*
+** Determine if we are dealing with Windows CE - which has a much reduced
+** API.
+*/
+#if defined(_WIN32_WCE)
+# define SQLITE_OS_WINCE 1
+#else
+# define SQLITE_OS_WINCE 0
+#endif
+
+/*
+** Determine if we are dealing with WinRT, which provides only a subset of
+** the full Win32 API.
+*/
+#if !defined(SQLITE_OS_WINRT)
+# define SQLITE_OS_WINRT 0
+#endif
+
+#endif /* _OS_WIN_H_ */
+
+/************** End of os_win.h **********************************************/
+/************** Continuing where we left off in mutex_w32.c ******************/
+#endif
+
+/*
+** The code in this file is only used if we are compiling multithreaded
+** on a win32 system.
+*/
+#ifdef SQLITE_MUTEX_W32
+
+/*
+** Each recursive mutex is an instance of the following structure.
+*/
+struct sqlite3_mutex {
+ CRITICAL_SECTION mutex; /* Mutex controlling the lock */
+ int id; /* Mutex type */
+#ifdef SQLITE_DEBUG
+ volatile int nRef; /* Number of enterances */
+ volatile DWORD owner; /* Thread holding this mutex */
+ int trace; /* True to trace changes */
+#endif
+};
+#define SQLITE_W32_MUTEX_INITIALIZER { 0 }
+#ifdef SQLITE_DEBUG
+#define SQLITE3_MUTEX_INITIALIZER { SQLITE_W32_MUTEX_INITIALIZER, 0, 0L, (DWORD)0, 0 }
+#else
+#define SQLITE3_MUTEX_INITIALIZER { SQLITE_W32_MUTEX_INITIALIZER, 0 }
+#endif
+
+/*
+** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
+** or WinCE. Return false (zero) for Win95, Win98, or WinME.
+**
+** Here is an interesting observation: Win95, Win98, and WinME lack
+** the LockFileEx() API. But we can still statically link against that
+** API as long as we don't call it win running Win95/98/ME. A call to
+** this routine is used to determine if the host is Win95/98/ME or
+** WinNT/2K/XP so that we will know whether or not we can safely call
+** the LockFileEx() API.
+**
+** mutexIsNT() is only used for the TryEnterCriticalSection() API call,
+** which is only available if your application was compiled with
+** _WIN32_WINNT defined to a value >= 0x0400. Currently, the only
+** call to TryEnterCriticalSection() is #ifdef'ed out, so #ifdef
+** this out as well.
+*/
+#if 0
+#if SQLITE_OS_WINCE || SQLITE_OS_WINRT
+# define mutexIsNT() (1)
+#else
+ static int mutexIsNT(void){
+ static int osType = 0;
+ if( osType==0 ){
+ OSVERSIONINFO sInfo;
+ sInfo.dwOSVersionInfoSize = sizeof(sInfo);
+ GetVersionEx(&sInfo);
+ osType = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
+ }
+ return osType==2;
+ }
+#endif /* SQLITE_OS_WINCE || SQLITE_OS_WINRT */
+#endif
+
+#ifdef SQLITE_DEBUG
+/*
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
+** intended for use only inside assert() statements.
+*/
+static int winMutexHeld(sqlite3_mutex *p){
+ return p->nRef!=0 && p->owner==GetCurrentThreadId();
+}
+static int winMutexNotheld2(sqlite3_mutex *p, DWORD tid){
+ return p->nRef==0 || p->owner!=tid;
+}
+static int winMutexNotheld(sqlite3_mutex *p){
+ DWORD tid = GetCurrentThreadId();
+ return winMutexNotheld2(p, tid);
+}
+#endif
+
+
+/*
+** Initialize and deinitialize the mutex subsystem.
+*/
+static sqlite3_mutex winMutex_staticMutexes[6] = {
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER,
+ SQLITE3_MUTEX_INITIALIZER
+};
+static int winMutex_isInit = 0;
+/* As winMutexInit() and winMutexEnd() are called as part
+** of the sqlite3_initialize and sqlite3_shutdown()
+** processing, the "interlocked" magic is probably not
+** strictly necessary.
+*/
+static LONG winMutex_lock = 0;
+
+SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */
+
+static int winMutexInit(void){
+ /* The first to increment to 1 does actual initialization */
+ if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
+ int i;
+ for(i=0; i
+** SQLITE_MUTEX_FAST
+** SQLITE_MUTEX_RECURSIVE
+** SQLITE_MUTEX_STATIC_MASTER
+** SQLITE_MUTEX_STATIC_MEM
+** SQLITE_MUTEX_STATIC_MEM2
+** SQLITE_MUTEX_STATIC_PRNG
+** SQLITE_MUTEX_STATIC_LRU
+** SQLITE_MUTEX_STATIC_PMEM
+**
+**
+** The first two constants cause sqlite3_mutex_alloc() to create
+** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
+** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
+** The mutex implementation does not need to make a distinction
+** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
+** not want to. But SQLite will only request a recursive mutex in
+** cases where it really needs one. If a faster non-recursive mutex
+** implementation is available on the host platform, the mutex subsystem
+** might return such a mutex in response to SQLITE_MUTEX_FAST.
+**
+** The other allowed parameters to sqlite3_mutex_alloc() each return
+** a pointer to a static preexisting mutex. Six static mutexes are
+** used by the current version of SQLite. Future versions of SQLite
+** may add additional static mutexes. Static mutexes are for internal
+** use by SQLite only. Applications that use SQLite mutexes should
+** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
+** SQLITE_MUTEX_RECURSIVE.
+**
+** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
+** returns a different mutex on every call. But for the static
+** mutex types, the same mutex is returned on every call that has
+** the same type number.
+*/
+static sqlite3_mutex *winMutexAlloc(int iType){
+ sqlite3_mutex *p;
+
+ switch( iType ){
+ case SQLITE_MUTEX_FAST:
+ case SQLITE_MUTEX_RECURSIVE: {
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+#ifdef SQLITE_DEBUG
+ p->id = iType;
+#endif
+#if SQLITE_OS_WINRT
+ InitializeCriticalSectionEx(&p->mutex, 0, 0);
+#else
+ InitializeCriticalSection(&p->mutex);
+#endif
+ }
+ break;
+ }
+ default: {
+ assert( winMutex_isInit==1 );
+ assert( iType-2 >= 0 );
+ assert( iType-2 < ArraySize(winMutex_staticMutexes) );
+ p = &winMutex_staticMutexes[iType-2];
+#ifdef SQLITE_DEBUG
+ p->id = iType;
+#endif
+ break;
+ }
+ }
+ return p;
+}
+
+
+/*
+** This routine deallocates a previously
+** allocated mutex. SQLite is careful to deallocate every
+** mutex that it allocates.
+*/
+static void winMutexFree(sqlite3_mutex *p){
+ assert( p );
+ assert( p->nRef==0 && p->owner==0 );
+ assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
+ DeleteCriticalSection(&p->mutex);
+ sqlite3_free(p);
+}
+
+/*
+** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex. If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
+** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
+** be entered multiple times by the same thread. In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter. If the same thread tries to enter any other kind of mutex
+** more than once, the behavior is undefined.
+*/
+static void winMutexEnter(sqlite3_mutex *p){
+#ifdef SQLITE_DEBUG
+ DWORD tid = GetCurrentThreadId();
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld2(p, tid) );
+#endif
+ EnterCriticalSection(&p->mutex);
+#ifdef SQLITE_DEBUG
+ assert( p->nRef>0 || p->owner==0 );
+ p->owner = tid;
+ p->nRef++;
+ if( p->trace ){
+ printf("enter mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+}
+static int winMutexTry(sqlite3_mutex *p){
+#ifndef NDEBUG
+ DWORD tid = GetCurrentThreadId();
+#endif
+ int rc = SQLITE_BUSY;
+ assert( p->id==SQLITE_MUTEX_RECURSIVE || winMutexNotheld2(p, tid) );
+ /*
+ ** The sqlite3_mutex_try() routine is very rarely used, and when it
+ ** is used it is merely an optimization. So it is OK for it to always
+ ** fail.
+ **
+ ** The TryEnterCriticalSection() interface is only available on WinNT.
+ ** And some windows compilers complain if you try to use it without
+ ** first doing some #defines that prevent SQLite from building on Win98.
+ ** For that reason, we will omit this optimization for now. See
+ ** ticket #2685.
+ */
+#if 0
+ if( mutexIsNT() && TryEnterCriticalSection(&p->mutex) ){
+ p->owner = tid;
+ p->nRef++;
+ rc = SQLITE_OK;
+ }
+#else
+ UNUSED_PARAMETER(p);
+#endif
+#ifdef SQLITE_DEBUG
+ if( rc==SQLITE_OK && p->trace ){
+ printf("try mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+ return rc;
+}
+
+/*
+** The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread. The behavior
+** is undefined if the mutex is not currently entered or
+** is not currently allocated. SQLite will never do either.
+*/
+static void winMutexLeave(sqlite3_mutex *p){
+#ifndef NDEBUG
+ DWORD tid = GetCurrentThreadId();
+ assert( p->nRef>0 );
+ assert( p->owner==tid );
+ p->nRef--;
+ if( p->nRef==0 ) p->owner = 0;
+ assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
+#endif
+ LeaveCriticalSection(&p->mutex);
+#ifdef SQLITE_DEBUG
+ if( p->trace ){
+ printf("leave mutex %p (%d) with nRef=%d\n", p, p->trace, p->nRef);
+ }
+#endif
+}
+
+SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
+ static const sqlite3_mutex_methods sMutex = {
+ winMutexInit,
+ winMutexEnd,
+ winMutexAlloc,
+ winMutexFree,
+ winMutexEnter,
+ winMutexTry,
+ winMutexLeave,
+#ifdef SQLITE_DEBUG
+ winMutexHeld,
+ winMutexNotheld
+#else
+ 0,
+ 0
+#endif
+ };
+
+ return &sMutex;
+}
+#endif /* SQLITE_MUTEX_W32 */
+
+/************** End of mutex_w32.c *******************************************/
+/************** Begin file malloc.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** Memory allocation functions used throughout sqlite.
+*/
+/* #include */
+
+/*
+** Attempt to release up to n bytes of non-essential memory currently
+** held by SQLite. An example of non-essential memory is memory used to
+** cache database pages that are not currently in use.
+*/
+SQLITE_API int sqlite3_release_memory(int n){
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+ return sqlite3PcacheReleaseMemory(n);
+#else
+ /* IMPLEMENTATION-OF: R-34391-24921 The sqlite3_release_memory() routine
+ ** is a no-op returning zero if SQLite is not compiled with
+ ** SQLITE_ENABLE_MEMORY_MANAGEMENT. */
+ UNUSED_PARAMETER(n);
+ return 0;
+#endif
+}
+
+/*
+** An instance of the following object records the location of
+** each unused scratch buffer.
+*/
+typedef struct ScratchFreeslot {
+ struct ScratchFreeslot *pNext; /* Next unused scratch buffer */
+} ScratchFreeslot;
+
+/*
+** State information local to the memory allocation subsystem.
+*/
+static SQLITE_WSD struct Mem0Global {
+ sqlite3_mutex *mutex; /* Mutex to serialize access */
+
+ /*
+ ** The alarm callback and its arguments. The mem0.mutex lock will
+ ** be held while the callback is running. Recursive calls into
+ ** the memory subsystem are allowed, but no new callbacks will be
+ ** issued.
+ */
+ sqlite3_int64 alarmThreshold;
+ void (*alarmCallback)(void*, sqlite3_int64,int);
+ void *alarmArg;
+
+ /*
+ ** Pointers to the end of sqlite3GlobalConfig.pScratch memory
+ ** (so that a range test can be used to determine if an allocation
+ ** being freed came from pScratch) and a pointer to the list of
+ ** unused scratch allocations.
+ */
+ void *pScratchEnd;
+ ScratchFreeslot *pScratchFree;
+ u32 nScratchFree;
+
+ /*
+ ** True if heap is nearly "full" where "full" is defined by the
+ ** sqlite3_soft_heap_limit() setting.
+ */
+ int nearlyFull;
+} mem0 = { 0, 0, 0, 0, 0, 0, 0, 0 };
+
+#define mem0 GLOBAL(struct Mem0Global, mem0)
+
+/*
+** This routine runs when the memory allocator sees that the
+** total memory allocation is about to exceed the soft heap
+** limit.
+*/
+static void softHeapLimitEnforcer(
+ void *NotUsed,
+ sqlite3_int64 NotUsed2,
+ int allocSize
+){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ sqlite3_release_memory(allocSize);
+}
+
+/*
+** Change the alarm callback
+*/
+static int sqlite3MemoryAlarm(
+ void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+ void *pArg,
+ sqlite3_int64 iThreshold
+){
+ int nUsed;
+ sqlite3_mutex_enter(mem0.mutex);
+ mem0.alarmCallback = xCallback;
+ mem0.alarmArg = pArg;
+ mem0.alarmThreshold = iThreshold;
+ nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+ mem0.nearlyFull = (iThreshold>0 && iThreshold<=nUsed);
+ sqlite3_mutex_leave(mem0.mutex);
+ return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Deprecated external interface. Internal/core SQLite code
+** should call sqlite3MemoryAlarm.
+*/
+SQLITE_API int sqlite3_memory_alarm(
+ void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+ void *pArg,
+ sqlite3_int64 iThreshold
+){
+ return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
+}
+#endif
+
+/*
+** Set the soft heap-size limit for the library. Passing a zero or
+** negative value indicates no limit.
+*/
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
+ sqlite3_int64 priorLimit;
+ sqlite3_int64 excess;
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return -1;
+#endif
+ sqlite3_mutex_enter(mem0.mutex);
+ priorLimit = mem0.alarmThreshold;
+ sqlite3_mutex_leave(mem0.mutex);
+ if( n<0 ) return priorLimit;
+ if( n>0 ){
+ sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, n);
+ }else{
+ sqlite3MemoryAlarm(0, 0, 0);
+ }
+ excess = sqlite3_memory_used() - n;
+ if( excess>0 ) sqlite3_release_memory((int)(excess & 0x7fffffff));
+ return priorLimit;
+}
+SQLITE_API void sqlite3_soft_heap_limit(int n){
+ if( n<0 ) n = 0;
+ sqlite3_soft_heap_limit64(n);
+}
+
+/*
+** Initialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE int sqlite3MallocInit(void){
+ if( sqlite3GlobalConfig.m.xMalloc==0 ){
+ sqlite3MemSetDefault();
+ }
+ memset(&mem0, 0, sizeof(mem0));
+ if( sqlite3GlobalConfig.bCoreMutex ){
+ mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
+ }
+ if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100
+ && sqlite3GlobalConfig.nScratch>0 ){
+ int i, n, sz;
+ ScratchFreeslot *pSlot;
+ sz = ROUNDDOWN8(sqlite3GlobalConfig.szScratch);
+ sqlite3GlobalConfig.szScratch = sz;
+ pSlot = (ScratchFreeslot*)sqlite3GlobalConfig.pScratch;
+ n = sqlite3GlobalConfig.nScratch;
+ mem0.pScratchFree = pSlot;
+ mem0.nScratchFree = n;
+ for(i=0; ipNext = (ScratchFreeslot*)(sz+(char*)pSlot);
+ pSlot = pSlot->pNext;
+ }
+ pSlot->pNext = 0;
+ mem0.pScratchEnd = (void*)&pSlot[1];
+ }else{
+ mem0.pScratchEnd = 0;
+ sqlite3GlobalConfig.pScratch = 0;
+ sqlite3GlobalConfig.szScratch = 0;
+ sqlite3GlobalConfig.nScratch = 0;
+ }
+ if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
+ || sqlite3GlobalConfig.nPage<1 ){
+ sqlite3GlobalConfig.pPage = 0;
+ sqlite3GlobalConfig.szPage = 0;
+ sqlite3GlobalConfig.nPage = 0;
+ }
+ return sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
+}
+
+/*
+** Return true if the heap is currently under memory pressure - in other
+** words if the amount of heap used is close to the limit set by
+** sqlite3_soft_heap_limit().
+*/
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void){
+ return mem0.nearlyFull;
+}
+
+/*
+** Deinitialize the memory allocation subsystem.
+*/
+SQLITE_PRIVATE void sqlite3MallocEnd(void){
+ if( sqlite3GlobalConfig.m.xShutdown ){
+ sqlite3GlobalConfig.m.xShutdown(sqlite3GlobalConfig.m.pAppData);
+ }
+ memset(&mem0, 0, sizeof(mem0));
+}
+
+/*
+** Return the amount of memory currently checked out.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void){
+ int n, mx;
+ sqlite3_int64 res;
+ sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, 0);
+ res = (sqlite3_int64)n; /* Work around bug in Borland C. Ticket #3216 */
+ return res;
+}
+
+/*
+** Return the maximum amount of memory that has ever been
+** checked out since either the beginning of this process
+** or since the most recent reset.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
+ int n, mx;
+ sqlite3_int64 res;
+ sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, resetFlag);
+ res = (sqlite3_int64)mx; /* Work around bug in Borland C. Ticket #3216 */
+ return res;
+}
+
+/*
+** Trigger the alarm
+*/
+static void sqlite3MallocAlarm(int nByte){
+ void (*xCallback)(void*,sqlite3_int64,int);
+ sqlite3_int64 nowUsed;
+ void *pArg;
+ if( mem0.alarmCallback==0 ) return;
+ xCallback = mem0.alarmCallback;
+ nowUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+ pArg = mem0.alarmArg;
+ mem0.alarmCallback = 0;
+ sqlite3_mutex_leave(mem0.mutex);
+ xCallback(pArg, nowUsed, nByte);
+ sqlite3_mutex_enter(mem0.mutex);
+ mem0.alarmCallback = xCallback;
+ mem0.alarmArg = pArg;
+}
+
+/*
+** Do a memory allocation with statistics and alarms. Assume the
+** lock is already held.
+*/
+static int mallocWithAlarm(int n, void **pp){
+ int nFull;
+ void *p;
+ assert( sqlite3_mutex_held(mem0.mutex) );
+ nFull = sqlite3GlobalConfig.m.xRoundup(n);
+ sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, n);
+ if( mem0.alarmCallback!=0 ){
+ int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+ if( nUsed >= mem0.alarmThreshold - nFull ){
+ mem0.nearlyFull = 1;
+ sqlite3MallocAlarm(nFull);
+ }else{
+ mem0.nearlyFull = 0;
+ }
+ }
+ p = sqlite3GlobalConfig.m.xMalloc(nFull);
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+ if( p==0 && mem0.alarmCallback ){
+ sqlite3MallocAlarm(nFull);
+ p = sqlite3GlobalConfig.m.xMalloc(nFull);
+ }
+#endif
+ if( p ){
+ nFull = sqlite3MallocSize(p);
+ sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nFull);
+ sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, 1);
+ }
+ *pp = p;
+ return nFull;
+}
+
+/*
+** Allocate memory. This routine is like sqlite3_malloc() except that it
+** assumes the memory subsystem has already been initialized.
+*/
+SQLITE_PRIVATE void *sqlite3Malloc(int n){
+ void *p;
+ if( n<=0 /* IMP: R-65312-04917 */
+ || n>=0x7fffff00
+ ){
+ /* A memory allocation of a number of bytes which is near the maximum
+ ** signed integer value might cause an integer overflow inside of the
+ ** xMalloc(). Hence we limit the maximum size to 0x7fffff00, giving
+ ** 255 bytes of overhead. SQLite itself will never use anything near
+ ** this amount. The only way to reach the limit is with sqlite3_malloc() */
+ p = 0;
+ }else if( sqlite3GlobalConfig.bMemstat ){
+ sqlite3_mutex_enter(mem0.mutex);
+ mallocWithAlarm(n, &p);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ p = sqlite3GlobalConfig.m.xMalloc(n);
+ }
+ assert( EIGHT_BYTE_ALIGNMENT(p) ); /* IMP: R-04675-44850 */
+ return p;
+}
+
+/*
+** This version of the memory allocation is for use by the application.
+** First make sure the memory subsystem is initialized, then do the
+** allocation.
+*/
+SQLITE_API void *sqlite3_malloc(int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return sqlite3Malloc(n);
+}
+
+/*
+** Each thread may only have a single outstanding allocation from
+** xScratchMalloc(). We verify this constraint in the single-threaded
+** case by setting scratchAllocOut to 1 when an allocation
+** is outstanding clearing it when the allocation is freed.
+*/
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+static int scratchAllocOut = 0;
+#endif
+
+
+/*
+** Allocate memory that is to be used and released right away.
+** This routine is similar to alloca() in that it is not intended
+** for situations where the memory might be held long-term. This
+** routine is intended to get memory to old large transient data
+** structures that would not normally fit on the stack of an
+** embedded processor.
+*/
+SQLITE_PRIVATE void *sqlite3ScratchMalloc(int n){
+ void *p;
+ assert( n>0 );
+
+ sqlite3_mutex_enter(mem0.mutex);
+ if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
+ p = mem0.pScratchFree;
+ mem0.pScratchFree = mem0.pScratchFree->pNext;
+ mem0.nScratchFree--;
+ sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
+ sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ if( sqlite3GlobalConfig.bMemstat ){
+ sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+ n = mallocWithAlarm(n, &p);
+ if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ sqlite3_mutex_leave(mem0.mutex);
+ p = sqlite3GlobalConfig.m.xMalloc(n);
+ }
+ sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
+ }
+ assert( sqlite3_mutex_notheld(mem0.mutex) );
+
+
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+ /* Verify that no more than two scratch allocations per thread
+ ** are outstanding at one time. (This is only checked in the
+ ** single-threaded case since checking in the multi-threaded case
+ ** would be much more complicated.) */
+ assert( scratchAllocOut<=1 );
+ if( p ) scratchAllocOut++;
+#endif
+
+ return p;
+}
+SQLITE_PRIVATE void sqlite3ScratchFree(void *p){
+ if( p ){
+
+#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
+ /* Verify that no more than two scratch allocation per thread
+ ** is outstanding at one time. (This is only checked in the
+ ** single-threaded case since checking in the multi-threaded case
+ ** would be much more complicated.) */
+ assert( scratchAllocOut>=1 && scratchAllocOut<=2 );
+ scratchAllocOut--;
+#endif
+
+ if( p>=sqlite3GlobalConfig.pScratch && ppNext = mem0.pScratchFree;
+ mem0.pScratchFree = pSlot;
+ mem0.nScratchFree++;
+ assert( mem0.nScratchFree <= (u32)sqlite3GlobalConfig.nScratch );
+ sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ /* Release memory back to the heap */
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) );
+ assert( sqlite3MemdebugNoType(p, ~MEMTYPE_SCRATCH) );
+ sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+ if( sqlite3GlobalConfig.bMemstat ){
+ int iSize = sqlite3MallocSize(p);
+ sqlite3_mutex_enter(mem0.mutex);
+ sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
+ sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
+ sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
+ sqlite3GlobalConfig.m.xFree(p);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ sqlite3GlobalConfig.m.xFree(p);
+ }
+ }
+ }
+}
+
+/*
+** TRUE if p is a lookaside memory allocation from db
+*/
+#ifndef SQLITE_OMIT_LOOKASIDE
+static int isLookaside(sqlite3 *db, void *p){
+ return p>=db->lookaside.pStart && plookaside.pEnd;
+}
+#else
+#define isLookaside(A,B) 0
+#endif
+
+/*
+** Return the size of a memory allocation previously obtained from
+** sqlite3Malloc() or sqlite3_malloc().
+*/
+SQLITE_PRIVATE int sqlite3MallocSize(void *p){
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+ assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
+ return sqlite3GlobalConfig.m.xSize(p);
+}
+SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
+ assert( db!=0 );
+ assert( sqlite3_mutex_held(db->mutex) );
+ if( isLookaside(db, p) ){
+ return db->lookaside.sz;
+ }else{
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+ assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+ return sqlite3GlobalConfig.m.xSize(p);
+ }
+}
+
+/*
+** Free memory previously obtained from sqlite3Malloc().
+*/
+SQLITE_API void sqlite3_free(void *p){
+ if( p==0 ) return; /* IMP: R-49053-54554 */
+ assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+ if( sqlite3GlobalConfig.bMemstat ){
+ sqlite3_mutex_enter(mem0.mutex);
+ sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
+ sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
+ sqlite3GlobalConfig.m.xFree(p);
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ sqlite3GlobalConfig.m.xFree(p);
+ }
+}
+
+/*
+** Free memory that might be associated with a particular database
+** connection.
+*/
+SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
+ assert( db==0 || sqlite3_mutex_held(db->mutex) );
+ if( p==0 ) return;
+ if( db ){
+ if( db->pnBytesFreed ){
+ *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
+ return;
+ }
+ if( isLookaside(db, p) ){
+ LookasideSlot *pBuf = (LookasideSlot*)p;
+#if SQLITE_DEBUG
+ /* Trash all content in the buffer being freed */
+ memset(p, 0xaa, db->lookaside.sz);
+#endif
+ pBuf->pNext = db->lookaside.pFree;
+ db->lookaside.pFree = pBuf;
+ db->lookaside.nOut--;
+ return;
+ }
+ }
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+ assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+ sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+ sqlite3_free(p);
+}
+
+/*
+** Change the size of an existing memory allocation
+*/
+SQLITE_PRIVATE void *sqlite3Realloc(void *pOld, int nBytes){
+ int nOld, nNew, nDiff;
+ void *pNew;
+ if( pOld==0 ){
+ return sqlite3Malloc(nBytes); /* IMP: R-28354-25769 */
+ }
+ if( nBytes<=0 ){
+ sqlite3_free(pOld); /* IMP: R-31593-10574 */
+ return 0;
+ }
+ if( nBytes>=0x7fffff00 ){
+ /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
+ return 0;
+ }
+ nOld = sqlite3MallocSize(pOld);
+ /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second
+ ** argument to xRealloc is always a value returned by a prior call to
+ ** xRoundup. */
+ nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
+ if( nOld==nNew ){
+ pNew = pOld;
+ }else if( sqlite3GlobalConfig.bMemstat ){
+ sqlite3_mutex_enter(mem0.mutex);
+ sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, nBytes);
+ nDiff = nNew - nOld;
+ if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >=
+ mem0.alarmThreshold-nDiff ){
+ sqlite3MallocAlarm(nDiff);
+ }
+ assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
+ assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );
+ pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+ if( pNew==0 && mem0.alarmCallback ){
+ sqlite3MallocAlarm(nBytes);
+ pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+ }
+ if( pNew ){
+ nNew = sqlite3MallocSize(pNew);
+ sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
+ }
+ sqlite3_mutex_leave(mem0.mutex);
+ }else{
+ pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
+ }
+ assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-04675-44850 */
+ return pNew;
+}
+
+/*
+** The public interface to sqlite3Realloc. Make sure that the memory
+** subsystem is initialized prior to invoking sqliteRealloc.
+*/
+SQLITE_API void *sqlite3_realloc(void *pOld, int n){
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ return sqlite3Realloc(pOld, n);
+}
+
+
+/*
+** Allocate and zero memory.
+*/
+SQLITE_PRIVATE void *sqlite3MallocZero(int n){
+ void *p = sqlite3Malloc(n);
+ if( p ){
+ memset(p, 0, n);
+ }
+ return p;
+}
+
+/*
+** Allocate and zero memory. If the allocation fails, make
+** the mallocFailed flag in the connection pointer.
+*/
+SQLITE_PRIVATE void *sqlite3DbMallocZero(sqlite3 *db, int n){
+ void *p = sqlite3DbMallocRaw(db, n);
+ if( p ){
+ memset(p, 0, n);
+ }
+ return p;
+}
+
+/*
+** Allocate and zero memory. If the allocation fails, make
+** the mallocFailed flag in the connection pointer.
+**
+** If db!=0 and db->mallocFailed is true (indicating a prior malloc
+** failure on the same database connection) then always return 0.
+** Hence for a particular database connection, once malloc starts
+** failing, it fails consistently until mallocFailed is reset.
+** This is an important assumption. There are many places in the
+** code that do things like this:
+**
+** int *a = (int*)sqlite3DbMallocRaw(db, 100);
+** int *b = (int*)sqlite3DbMallocRaw(db, 200);
+** if( b ) a[10] = 9;
+**
+** In other words, if a subsequent malloc (ex: "b") worked, it is assumed
+** that all prior mallocs (ex: "a") worked too.
+*/
+SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, int n){
+ void *p;
+ assert( db==0 || sqlite3_mutex_held(db->mutex) );
+ assert( db==0 || db->pnBytesFreed==0 );
+#ifndef SQLITE_OMIT_LOOKASIDE
+ if( db ){
+ LookasideSlot *pBuf;
+ if( db->mallocFailed ){
+ return 0;
+ }
+ if( db->lookaside.bEnabled ){
+ if( n>db->lookaside.sz ){
+ db->lookaside.anStat[1]++;
+ }else if( (pBuf = db->lookaside.pFree)==0 ){
+ db->lookaside.anStat[2]++;
+ }else{
+ db->lookaside.pFree = pBuf->pNext;
+ db->lookaside.nOut++;
+ db->lookaside.anStat[0]++;
+ if( db->lookaside.nOut>db->lookaside.mxOut ){
+ db->lookaside.mxOut = db->lookaside.nOut;
+ }
+ return (void*)pBuf;
+ }
+ }
+ }
+#else
+ if( db && db->mallocFailed ){
+ return 0;
+ }
+#endif
+ p = sqlite3Malloc(n);
+ if( !p && db ){
+ db->mallocFailed = 1;
+ }
+ sqlite3MemdebugSetType(p, MEMTYPE_DB |
+ ((db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
+ return p;
+}
+
+/*
+** Resize the block of memory pointed to by p to n bytes. If the
+** resize fails, set the mallocFailed flag in the connection object.
+*/
+SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *db, void *p, int n){
+ void *pNew = 0;
+ assert( db!=0 );
+ assert( sqlite3_mutex_held(db->mutex) );
+ if( db->mallocFailed==0 ){
+ if( p==0 ){
+ return sqlite3DbMallocRaw(db, n);
+ }
+ if( isLookaside(db, p) ){
+ if( n<=db->lookaside.sz ){
+ return p;
+ }
+ pNew = sqlite3DbMallocRaw(db, n);
+ if( pNew ){
+ memcpy(pNew, p, db->lookaside.sz);
+ sqlite3DbFree(db, p);
+ }
+ }else{
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+ assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+ sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+ pNew = sqlite3_realloc(p, n);
+ if( !pNew ){
+ sqlite3MemdebugSetType(p, MEMTYPE_DB|MEMTYPE_HEAP);
+ db->mallocFailed = 1;
+ }
+ sqlite3MemdebugSetType(pNew, MEMTYPE_DB |
+ (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
+ }
+ }
+ return pNew;
+}
+
+/*
+** Attempt to reallocate p. If the reallocation fails, then free p
+** and set the mallocFailed flag in the database connection.
+*/
+SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, int n){
+ void *pNew;
+ pNew = sqlite3DbRealloc(db, p, n);
+ if( !pNew ){
+ sqlite3DbFree(db, p);
+ }
+ return pNew;
+}
+
+/*
+** Make a copy of a string in memory obtained from sqliteMalloc(). These
+** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This
+** is because when memory debugging is turned on, these two functions are
+** called via macros that record the current file and line number in the
+** ThreadData structure.
+*/
+SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3 *db, const char *z){
+ char *zNew;
+ size_t n;
+ if( z==0 ){
+ return 0;
+ }
+ n = sqlite3Strlen30(z) + 1;
+ assert( (n&0x7fffffff)==n );
+ zNew = sqlite3DbMallocRaw(db, (int)n);
+ if( zNew ){
+ memcpy(zNew, z, n);
+ }
+ return zNew;
+}
+SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3 *db, const char *z, int n){
+ char *zNew;
+ if( z==0 ){
+ return 0;
+ }
+ assert( (n&0x7fffffff)==n );
+ zNew = sqlite3DbMallocRaw(db, n+1);
+ if( zNew ){
+ memcpy(zNew, z, n);
+ zNew[n] = 0;
+ }
+ return zNew;
+}
+
+/*
+** Create a string from the zFromat argument and the va_list that follows.
+** Store the string in memory obtained from sqliteMalloc() and make *pz
+** point to that string.
+*/
+SQLITE_PRIVATE void sqlite3SetString(char **pz, sqlite3 *db, const char *zFormat, ...){
+ va_list ap;
+ char *z;
+
+ va_start(ap, zFormat);
+ z = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ sqlite3DbFree(db, *pz);
+ *pz = z;
+}
+
+
+/*
+** This function must be called before exiting any API function (i.e.
+** returning control to the user) that has called sqlite3_malloc or
+** sqlite3_realloc.
+**
+** The returned value is normally a copy of the second argument to this
+** function. However, if a malloc() failure has occurred since the previous
+** invocation SQLITE_NOMEM is returned instead.
+**
+** If the first argument, db, is not NULL and a malloc() error has occurred,
+** then the connection error-code (the value returned by sqlite3_errcode())
+** is set to SQLITE_NOMEM.
+*/
+SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
+ /* If the db handle is not NULL, then we must hold the connection handle
+ ** mutex here. Otherwise the read (and possible write) of db->mallocFailed
+ ** is unsafe, as is the call to sqlite3Error().
+ */
+ assert( !db || sqlite3_mutex_held(db->mutex) );
+ if( db && (db->mallocFailed || rc==SQLITE_IOERR_NOMEM) ){
+ sqlite3Error(db, SQLITE_NOMEM, 0);
+ db->mallocFailed = 0;
+ rc = SQLITE_NOMEM;
+ }
+ return rc & (db ? db->errMask : 0xff);
+}
+
+/************** End of malloc.c **********************************************/
+/************** Begin file printf.c ******************************************/
+/*
+** The "printf" code that follows dates from the 1980's. It is in
+** the public domain. The original comments are included here for
+** completeness. They are very out-of-date but might be useful as
+** an historical reference. Most of the "enhancements" have been backed
+** out so that the functionality is now the same as standard printf().
+**
+**************************************************************************
+**
+** This file contains code for a set of "printf"-like routines. These
+** routines format strings much like the printf() from the standard C
+** library, though the implementation here has enhancements to support
+** SQLlite.
+*/
+
+/*
+** Conversion types fall into various categories as defined by the
+** following enumeration.
+*/
+#define etRADIX 1 /* Integer types. %d, %x, %o, and so forth */
+#define etFLOAT 2 /* Floating point. %f */
+#define etEXP 3 /* Exponentional notation. %e and %E */
+#define etGENERIC 4 /* Floating or exponential, depending on exponent. %g */
+#define etSIZE 5 /* Return number of characters processed so far. %n */
+#define etSTRING 6 /* Strings. %s */
+#define etDYNSTRING 7 /* Dynamically allocated strings. %z */
+#define etPERCENT 8 /* Percent symbol. %% */
+#define etCHARX 9 /* Characters. %c */
+/* The rest are extensions, not normally found in printf() */
+#define etSQLESCAPE 10 /* Strings with '\'' doubled. %q */
+#define etSQLESCAPE2 11 /* Strings with '\'' doubled and enclosed in '',
+ NULL pointers replaced by SQL NULL. %Q */
+#define etTOKEN 12 /* a pointer to a Token structure */
+#define etSRCLIST 13 /* a pointer to a SrcList */
+#define etPOINTER 14 /* The %p conversion */
+#define etSQLESCAPE3 15 /* %w -> Strings with '\"' doubled */
+#define etORDINAL 16 /* %r -> 1st, 2nd, 3rd, 4th, etc. English only */
+
+#define etINVALID 0 /* Any unrecognized conversion type */
+
+
+/*
+** An "etByte" is an 8-bit unsigned value.
+*/
+typedef unsigned char etByte;
+
+/*
+** Each builtin conversion character (ex: the 'd' in "%d") is described
+** by an instance of the following structure
+*/
+typedef struct et_info { /* Information about each format field */
+ char fmttype; /* The format field code letter */
+ etByte base; /* The base for radix conversion */
+ etByte flags; /* One or more of FLAG_ constants below */
+ etByte type; /* Conversion paradigm */
+ etByte charset; /* Offset into aDigits[] of the digits string */
+ etByte prefix; /* Offset into aPrefix[] of the prefix string */
+} et_info;
+
+/*
+** Allowed values for et_info.flags
+*/
+#define FLAG_SIGNED 1 /* True if the value to convert is signed */
+#define FLAG_INTERN 2 /* True if for internal use only */
+#define FLAG_STRING 4 /* Allow infinity precision */
+
+
+/*
+** The following table is searched linearly, so it is good to put the
+** most frequently used conversion types first.
+*/
+static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
+static const char aPrefix[] = "-x0\000X0";
+static const et_info fmtinfo[] = {
+ { 'd', 10, 1, etRADIX, 0, 0 },
+ { 's', 0, 4, etSTRING, 0, 0 },
+ { 'g', 0, 1, etGENERIC, 30, 0 },
+ { 'z', 0, 4, etDYNSTRING, 0, 0 },
+ { 'q', 0, 4, etSQLESCAPE, 0, 0 },
+ { 'Q', 0, 4, etSQLESCAPE2, 0, 0 },
+ { 'w', 0, 4, etSQLESCAPE3, 0, 0 },
+ { 'c', 0, 0, etCHARX, 0, 0 },
+ { 'o', 8, 0, etRADIX, 0, 2 },
+ { 'u', 10, 0, etRADIX, 0, 0 },
+ { 'x', 16, 0, etRADIX, 16, 1 },
+ { 'X', 16, 0, etRADIX, 0, 4 },
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ { 'f', 0, 1, etFLOAT, 0, 0 },
+ { 'e', 0, 1, etEXP, 30, 0 },
+ { 'E', 0, 1, etEXP, 14, 0 },
+ { 'G', 0, 1, etGENERIC, 14, 0 },
+#endif
+ { 'i', 10, 1, etRADIX, 0, 0 },
+ { 'n', 0, 0, etSIZE, 0, 0 },
+ { '%', 0, 0, etPERCENT, 0, 0 },
+ { 'p', 16, 0, etPOINTER, 0, 1 },
+
+/* All the rest have the FLAG_INTERN bit set and are thus for internal
+** use only */
+ { 'T', 0, 2, etTOKEN, 0, 0 },
+ { 'S', 0, 2, etSRCLIST, 0, 0 },
+ { 'r', 10, 3, etORDINAL, 0, 0 },
+};
+
+/*
+** If SQLITE_OMIT_FLOATING_POINT is defined, then none of the floating point
+** conversions will work.
+*/
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** "*val" is a double such that 0.1 <= *val < 10.0
+** Return the ascii code for the leading digit of *val, then
+** multiply "*val" by 10.0 to renormalize.
+**
+** Example:
+** input: *val = 3.14159
+** output: *val = 1.4159 function return = '3'
+**
+** The counter *cnt is incremented each time. After counter exceeds
+** 16 (the number of significant digits in a 64-bit float) '0' is
+** always returned.
+*/
+static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
+ int digit;
+ LONGDOUBLE_TYPE d;
+ if( (*cnt)<=0 ) return '0';
+ (*cnt)--;
+ digit = (int)*val;
+ d = digit;
+ digit += '0';
+ *val = (*val - d)*10.0;
+ return (char)digit;
+}
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+
+/*
+** Set the StrAccum object to an error mode.
+*/
+static void setStrAccumError(StrAccum *p, u8 eError){
+ p->accError = eError;
+ p->nAlloc = 0;
+}
+
+/*
+** Extra argument values from a PrintfArguments object
+*/
+static sqlite3_int64 getIntArg(PrintfArguments *p){
+ if( p->nArg<=p->nUsed ) return 0;
+ return sqlite3_value_int64(p->apArg[p->nUsed++]);
+}
+static double getDoubleArg(PrintfArguments *p){
+ if( p->nArg<=p->nUsed ) return 0.0;
+ return sqlite3_value_double(p->apArg[p->nUsed++]);
+}
+static char *getTextArg(PrintfArguments *p){
+ if( p->nArg<=p->nUsed ) return 0;
+ return (char*)sqlite3_value_text(p->apArg[p->nUsed++]);
+}
+
+
+/*
+** On machines with a small stack size, you can redefine the
+** SQLITE_PRINT_BUF_SIZE to be something smaller, if desired.
+*/
+#ifndef SQLITE_PRINT_BUF_SIZE
+# define SQLITE_PRINT_BUF_SIZE 70
+#endif
+#define etBUFSIZE SQLITE_PRINT_BUF_SIZE /* Size of the output buffer */
+
+/*
+** Render a string given by "fmt" into the StrAccum object.
+*/
+SQLITE_PRIVATE void sqlite3VXPrintf(
+ StrAccum *pAccum, /* Accumulate results here */
+ u32 bFlags, /* SQLITE_PRINTF_* flags */
+ const char *fmt, /* Format string */
+ va_list ap /* arguments */
+){
+ int c; /* Next character in the format string */
+ char *bufpt; /* Pointer to the conversion buffer */
+ int precision; /* Precision of the current field */
+ int length; /* Length of the field */
+ int idx; /* A general purpose loop counter */
+ int width; /* Width of the current field */
+ etByte flag_leftjustify; /* True if "-" flag is present */
+ etByte flag_plussign; /* True if "+" flag is present */
+ etByte flag_blanksign; /* True if " " flag is present */
+ etByte flag_alternateform; /* True if "#" flag is present */
+ etByte flag_altform2; /* True if "!" flag is present */
+ etByte flag_zeropad; /* True if field width constant starts with zero */
+ etByte flag_long; /* True if "l" flag is present */
+ etByte flag_longlong; /* True if the "ll" flag is present */
+ etByte done; /* Loop termination flag */
+ etByte xtype = 0; /* Conversion paradigm */
+ u8 bArgList; /* True for SQLITE_PRINTF_SQLFUNC */
+ u8 useIntern; /* Ok to use internal conversions (ex: %T) */
+ char prefix; /* Prefix character. "+" or "-" or " " or '\0'. */
+ sqlite_uint64 longvalue; /* Value for integer types */
+ LONGDOUBLE_TYPE realvalue; /* Value for real types */
+ const et_info *infop; /* Pointer to the appropriate info structure */
+ char *zOut; /* Rendering buffer */
+ int nOut; /* Size of the rendering buffer */
+ char *zExtra; /* Malloced memory used by some conversion */
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ int exp, e2; /* exponent of real numbers */
+ int nsd; /* Number of significant digits returned */
+ double rounder; /* Used for rounding floating point values */
+ etByte flag_dp; /* True if decimal point should be shown */
+ etByte flag_rtz; /* True if trailing zeros should be removed */
+#endif
+ PrintfArguments *pArgList = 0; /* Arguments for SQLITE_PRINTF_SQLFUNC */
+ char buf[etBUFSIZE]; /* Conversion buffer */
+
+ bufpt = 0;
+ if( bFlags ){
+ if( (bArgList = (bFlags & SQLITE_PRINTF_SQLFUNC))!=0 ){
+ pArgList = va_arg(ap, PrintfArguments*);
+ }
+ useIntern = bFlags & SQLITE_PRINTF_INTERNAL;
+ }else{
+ bArgList = useIntern = 0;
+ }
+ for(; (c=(*fmt))!=0; ++fmt){
+ if( c!='%' ){
+ bufpt = (char *)fmt;
+ while( (c=(*++fmt))!='%' && c!=0 ){};
+ sqlite3StrAccumAppend(pAccum, bufpt, (int)(fmt - bufpt));
+ if( c==0 ) break;
+ }
+ if( (c=(*++fmt))==0 ){
+ sqlite3StrAccumAppend(pAccum, "%", 1);
+ break;
+ }
+ /* Find out what flags are present */
+ flag_leftjustify = flag_plussign = flag_blanksign =
+ flag_alternateform = flag_altform2 = flag_zeropad = 0;
+ done = 0;
+ do{
+ switch( c ){
+ case '-': flag_leftjustify = 1; break;
+ case '+': flag_plussign = 1; break;
+ case ' ': flag_blanksign = 1; break;
+ case '#': flag_alternateform = 1; break;
+ case '!': flag_altform2 = 1; break;
+ case '0': flag_zeropad = 1; break;
+ default: done = 1; break;
+ }
+ }while( !done && (c=(*++fmt))!=0 );
+ /* Get the field width */
+ width = 0;
+ if( c=='*' ){
+ if( bArgList ){
+ width = (int)getIntArg(pArgList);
+ }else{
+ width = va_arg(ap,int);
+ }
+ if( width<0 ){
+ flag_leftjustify = 1;
+ width = -width;
+ }
+ c = *++fmt;
+ }else{
+ while( c>='0' && c<='9' ){
+ width = width*10 + c - '0';
+ c = *++fmt;
+ }
+ }
+ /* Get the precision */
+ if( c=='.' ){
+ precision = 0;
+ c = *++fmt;
+ if( c=='*' ){
+ if( bArgList ){
+ precision = (int)getIntArg(pArgList);
+ }else{
+ precision = va_arg(ap,int);
+ }
+ if( precision<0 ) precision = -precision;
+ c = *++fmt;
+ }else{
+ while( c>='0' && c<='9' ){
+ precision = precision*10 + c - '0';
+ c = *++fmt;
+ }
+ }
+ }else{
+ precision = -1;
+ }
+ /* Get the conversion type modifier */
+ if( c=='l' ){
+ flag_long = 1;
+ c = *++fmt;
+ if( c=='l' ){
+ flag_longlong = 1;
+ c = *++fmt;
+ }else{
+ flag_longlong = 0;
+ }
+ }else{
+ flag_long = flag_longlong = 0;
+ }
+ /* Fetch the info entry for the field */
+ infop = &fmtinfo[0];
+ xtype = etINVALID;
+ for(idx=0; idxflags & FLAG_INTERN)==0 ){
+ xtype = infop->type;
+ }else{
+ return;
+ }
+ break;
+ }
+ }
+ zExtra = 0;
+
+ /*
+ ** At this point, variables are initialized as follows:
+ **
+ ** flag_alternateform TRUE if a '#' is present.
+ ** flag_altform2 TRUE if a '!' is present.
+ ** flag_plussign TRUE if a '+' is present.
+ ** flag_leftjustify TRUE if a '-' is present or if the
+ ** field width was negative.
+ ** flag_zeropad TRUE if the width began with 0.
+ ** flag_long TRUE if the letter 'l' (ell) prefixed
+ ** the conversion character.
+ ** flag_longlong TRUE if the letter 'll' (ell ell) prefixed
+ ** the conversion character.
+ ** flag_blanksign TRUE if a ' ' is present.
+ ** width The specified field width. This is
+ ** always non-negative. Zero is the default.
+ ** precision The specified precision. The default
+ ** is -1.
+ ** xtype The class of the conversion.
+ ** infop Pointer to the appropriate info struct.
+ */
+ switch( xtype ){
+ case etPOINTER:
+ flag_longlong = sizeof(char*)==sizeof(i64);
+ flag_long = sizeof(char*)==sizeof(long int);
+ /* Fall through into the next case */
+ case etORDINAL:
+ case etRADIX:
+ if( infop->flags & FLAG_SIGNED ){
+ i64 v;
+ if( bArgList ){
+ v = getIntArg(pArgList);
+ }else if( flag_longlong ){
+ v = va_arg(ap,i64);
+ }else if( flag_long ){
+ v = va_arg(ap,long int);
+ }else{
+ v = va_arg(ap,int);
+ }
+ if( v<0 ){
+ if( v==SMALLEST_INT64 ){
+ longvalue = ((u64)1)<<63;
+ }else{
+ longvalue = -v;
+ }
+ prefix = '-';
+ }else{
+ longvalue = v;
+ if( flag_plussign ) prefix = '+';
+ else if( flag_blanksign ) prefix = ' ';
+ else prefix = 0;
+ }
+ }else{
+ if( bArgList ){
+ longvalue = (u64)getIntArg(pArgList);
+ }else if( flag_longlong ){
+ longvalue = va_arg(ap,u64);
+ }else if( flag_long ){
+ longvalue = va_arg(ap,unsigned long int);
+ }else{
+ longvalue = va_arg(ap,unsigned int);
+ }
+ prefix = 0;
+ }
+ if( longvalue==0 ) flag_alternateform = 0;
+ if( flag_zeropad && precision=4 || (longvalue/10)%10==1 ){
+ x = 0;
+ }
+ *(--bufpt) = zOrd[x*2+1];
+ *(--bufpt) = zOrd[x*2];
+ }
+ {
+ const char *cset = &aDigits[infop->charset];
+ u8 base = infop->base;
+ do{ /* Convert to ascii */
+ *(--bufpt) = cset[longvalue%base];
+ longvalue = longvalue/base;
+ }while( longvalue>0 );
+ }
+ length = (int)(&zOut[nOut-1]-bufpt);
+ for(idx=precision-length; idx>0; idx--){
+ *(--bufpt) = '0'; /* Zero pad */
+ }
+ if( prefix ) *(--bufpt) = prefix; /* Add sign */
+ if( flag_alternateform && infop->prefix ){ /* Add "0" or "0x" */
+ const char *pre;
+ char x;
+ pre = &aPrefix[infop->prefix];
+ for(; (x=(*pre))!=0; pre++) *(--bufpt) = x;
+ }
+ length = (int)(&zOut[nOut-1]-bufpt);
+ break;
+ case etFLOAT:
+ case etEXP:
+ case etGENERIC:
+ if( bArgList ){
+ realvalue = getDoubleArg(pArgList);
+ }else{
+ realvalue = va_arg(ap,double);
+ }
+#ifdef SQLITE_OMIT_FLOATING_POINT
+ length = 0;
+#else
+ if( precision<0 ) precision = 6; /* Set default precision */
+ if( realvalue<0.0 ){
+ realvalue = -realvalue;
+ prefix = '-';
+ }else{
+ if( flag_plussign ) prefix = '+';
+ else if( flag_blanksign ) prefix = ' ';
+ else prefix = 0;
+ }
+ if( xtype==etGENERIC && precision>0 ) precision--;
+ for(idx=precision, rounder=0.5; idx>0; idx--, rounder*=0.1){}
+ if( xtype==etFLOAT ) realvalue += rounder;
+ /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
+ exp = 0;
+ if( sqlite3IsNaN((double)realvalue) ){
+ bufpt = "NaN";
+ length = 3;
+ break;
+ }
+ if( realvalue>0.0 ){
+ LONGDOUBLE_TYPE scale = 1.0;
+ while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
+ while( realvalue>=1e64*scale && exp<=350 ){ scale *= 1e64; exp+=64; }
+ while( realvalue>=1e8*scale && exp<=350 ){ scale *= 1e8; exp+=8; }
+ while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
+ realvalue /= scale;
+ while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
+ while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
+ if( exp>350 ){
+ if( prefix=='-' ){
+ bufpt = "-Inf";
+ }else if( prefix=='+' ){
+ bufpt = "+Inf";
+ }else{
+ bufpt = "Inf";
+ }
+ length = sqlite3Strlen30(bufpt);
+ break;
+ }
+ }
+ bufpt = buf;
+ /*
+ ** If the field type is etGENERIC, then convert to either etEXP
+ ** or etFLOAT, as appropriate.
+ */
+ if( xtype!=etFLOAT ){
+ realvalue += rounder;
+ if( realvalue>=10.0 ){ realvalue *= 0.1; exp++; }
+ }
+ if( xtype==etGENERIC ){
+ flag_rtz = !flag_alternateform;
+ if( exp<-4 || exp>precision ){
+ xtype = etEXP;
+ }else{
+ precision = precision - exp;
+ xtype = etFLOAT;
+ }
+ }else{
+ flag_rtz = flag_altform2;
+ }
+ if( xtype==etEXP ){
+ e2 = 0;
+ }else{
+ e2 = exp;
+ }
+ if( MAX(e2,0)+precision+width > etBUFSIZE - 15 ){
+ bufpt = zExtra = sqlite3Malloc( MAX(e2,0)+precision+width+15 );
+ if( bufpt==0 ){
+ setStrAccumError(pAccum, STRACCUM_NOMEM);
+ return;
+ }
+ }
+ zOut = bufpt;
+ nsd = 16 + flag_altform2*10;
+ flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
+ /* The sign in front of the number */
+ if( prefix ){
+ *(bufpt++) = prefix;
+ }
+ /* Digits prior to the decimal point */
+ if( e2<0 ){
+ *(bufpt++) = '0';
+ }else{
+ for(; e2>=0; e2--){
+ *(bufpt++) = et_getdigit(&realvalue,&nsd);
+ }
+ }
+ /* The decimal point */
+ if( flag_dp ){
+ *(bufpt++) = '.';
+ }
+ /* "0" digits after the decimal point but before the first
+ ** significant digit of the number */
+ for(e2++; e2<0; precision--, e2++){
+ assert( precision>0 );
+ *(bufpt++) = '0';
+ }
+ /* Significant digits after the decimal point */
+ while( (precision--)>0 ){
+ *(bufpt++) = et_getdigit(&realvalue,&nsd);
+ }
+ /* Remove trailing zeros and the "." if no digits follow the "." */
+ if( flag_rtz && flag_dp ){
+ while( bufpt[-1]=='0' ) *(--bufpt) = 0;
+ assert( bufpt>zOut );
+ if( bufpt[-1]=='.' ){
+ if( flag_altform2 ){
+ *(bufpt++) = '0';
+ }else{
+ *(--bufpt) = 0;
+ }
+ }
+ }
+ /* Add the "eNNN" suffix */
+ if( xtype==etEXP ){
+ *(bufpt++) = aDigits[infop->charset];
+ if( exp<0 ){
+ *(bufpt++) = '-'; exp = -exp;
+ }else{
+ *(bufpt++) = '+';
+ }
+ if( exp>=100 ){
+ *(bufpt++) = (char)((exp/100)+'0'); /* 100's digit */
+ exp %= 100;
+ }
+ *(bufpt++) = (char)(exp/10+'0'); /* 10's digit */
+ *(bufpt++) = (char)(exp%10+'0'); /* 1's digit */
+ }
+ *bufpt = 0;
+
+ /* The converted number is in buf[] and zero terminated. Output it.
+ ** Note that the number is in the usual order, not reversed as with
+ ** integer conversions. */
+ length = (int)(bufpt-zOut);
+ bufpt = zOut;
+
+ /* Special case: Add leading zeros if the flag_zeropad flag is
+ ** set and we are not left justified */
+ if( flag_zeropad && !flag_leftjustify && length < width){
+ int i;
+ int nPad = width - length;
+ for(i=width; i>=nPad; i--){
+ bufpt[i] = bufpt[i-nPad];
+ }
+ i = prefix!=0;
+ while( nPad-- ) bufpt[i++] = '0';
+ length = width;
+ }
+#endif /* !defined(SQLITE_OMIT_FLOATING_POINT) */
+ break;
+ case etSIZE:
+ if( !bArgList ){
+ *(va_arg(ap,int*)) = pAccum->nChar;
+ }
+ length = width = 0;
+ break;
+ case etPERCENT:
+ buf[0] = '%';
+ bufpt = buf;
+ length = 1;
+ break;
+ case etCHARX:
+ if( bArgList ){
+ bufpt = getTextArg(pArgList);
+ c = bufpt ? bufpt[0] : 0;
+ }else{
+ c = va_arg(ap,int);
+ }
+ buf[0] = (char)c;
+ if( precision>=0 ){
+ for(idx=1; idx=0 ){
+ for(length=0; lengthetBUFSIZE ){
+ bufpt = zExtra = sqlite3Malloc( n );
+ if( bufpt==0 ){
+ setStrAccumError(pAccum, STRACCUM_NOMEM);
+ return;
+ }
+ }else{
+ bufpt = buf;
+ }
+ j = 0;
+ if( needQuote ) bufpt[j++] = q;
+ k = i;
+ for(i=0; i=0 && precisionn ){
+ sqlite3StrAccumAppend(pAccum, (const char*)pToken->z, pToken->n);
+ }
+ length = width = 0;
+ break;
+ }
+ case etSRCLIST: {
+ SrcList *pSrc = va_arg(ap, SrcList*);
+ int k = va_arg(ap, int);
+ struct SrcList_item *pItem = &pSrc->a[k];
+ assert( bArgList==0 );
+ assert( k>=0 && knSrc );
+ if( pItem->zDatabase ){
+ sqlite3StrAccumAppendAll(pAccum, pItem->zDatabase);
+ sqlite3StrAccumAppend(pAccum, ".", 1);
+ }
+ sqlite3StrAccumAppendAll(pAccum, pItem->zName);
+ length = width = 0;
+ break;
+ }
+ default: {
+ assert( xtype==etINVALID );
+ return;
+ }
+ }/* End switch over the format type */
+ /*
+ ** The text of the conversion is pointed to by "bufpt" and is
+ ** "length" characters long. The field width is "width". Do
+ ** the output.
+ */
+ width -= length;
+ if( width>0 && !flag_leftjustify ) sqlite3AppendSpace(pAccum, width);
+ sqlite3StrAccumAppend(pAccum, bufpt, length);
+ if( width>0 && flag_leftjustify ) sqlite3AppendSpace(pAccum, width);
+
+ if( zExtra ) sqlite3_free(zExtra);
+ }/* End for loop over the format string */
+} /* End of function */
+
+/*
+** Enlarge the memory allocation on a StrAccum object so that it is
+** able to accept at least N more bytes of text.
+**
+** Return the number of bytes of text that StrAccum is able to accept
+** after the attempted enlargement. The value returned might be zero.
+*/
+static int sqlite3StrAccumEnlarge(StrAccum *p, int N){
+ char *zNew;
+ assert( p->nChar+N >= p->nAlloc ); /* Only called if really needed */
+ if( p->accError ){
+ testcase(p->accError==STRACCUM_TOOBIG);
+ testcase(p->accError==STRACCUM_NOMEM);
+ return 0;
+ }
+ if( !p->useMalloc ){
+ N = p->nAlloc - p->nChar - 1;
+ setStrAccumError(p, STRACCUM_TOOBIG);
+ return N;
+ }else{
+ char *zOld = (p->zText==p->zBase ? 0 : p->zText);
+ i64 szNew = p->nChar;
+ szNew += N + 1;
+ if( szNew > p->mxAlloc ){
+ sqlite3StrAccumReset(p);
+ setStrAccumError(p, STRACCUM_TOOBIG);
+ return 0;
+ }else{
+ p->nAlloc = (int)szNew;
+ }
+ if( p->useMalloc==1 ){
+ zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
+ }else{
+ zNew = sqlite3_realloc(zOld, p->nAlloc);
+ }
+ if( zNew ){
+ assert( p->zText!=0 || p->nChar==0 );
+ if( zOld==0 && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
+ p->zText = zNew;
+ }else{
+ sqlite3StrAccumReset(p);
+ setStrAccumError(p, STRACCUM_NOMEM);
+ return 0;
+ }
+ }
+ return N;
+}
+
+/*
+** Append N space characters to the given string buffer.
+*/
+SQLITE_PRIVATE void sqlite3AppendSpace(StrAccum *p, int N){
+ if( p->nChar+N >= p->nAlloc && (N = sqlite3StrAccumEnlarge(p, N))<=0 ) return;
+ while( (N--)>0 ) p->zText[p->nChar++] = ' ';
+}
+
+/*
+** The StrAccum "p" is not large enough to accept N new bytes of z[].
+** So enlarge if first, then do the append.
+**
+** This is a helper routine to sqlite3StrAccumAppend() that does special-case
+** work (enlarging the buffer) using tail recursion, so that the
+** sqlite3StrAccumAppend() routine can use fast calling semantics.
+*/
+static void enlargeAndAppend(StrAccum *p, const char *z, int N){
+ N = sqlite3StrAccumEnlarge(p, N);
+ if( N>0 ){
+ memcpy(&p->zText[p->nChar], z, N);
+ p->nChar += N;
+ }
+}
+
+/*
+** Append N bytes of text from z to the StrAccum object. Increase the
+** size of the memory allocation for StrAccum if necessary.
+*/
+SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
+ assert( z!=0 );
+ assert( p->zText!=0 || p->nChar==0 || p->accError );
+ assert( N>=0 );
+ assert( p->accError==0 || p->nAlloc==0 );
+ if( p->nChar+N >= p->nAlloc ){
+ enlargeAndAppend(p,z,N);
+ return;
+ }
+ assert( p->zText );
+ memcpy(&p->zText[p->nChar], z, N);
+ p->nChar += N;
+}
+
+/*
+** Append the complete text of zero-terminated string z[] to the p string.
+*/
+SQLITE_PRIVATE void sqlite3StrAccumAppendAll(StrAccum *p, const char *z){
+ sqlite3StrAccumAppend(p, z, sqlite3Strlen30(z));
+}
+
+
+/*
+** Finish off a string by making sure it is zero-terminated.
+** Return a pointer to the resulting string. Return a NULL
+** pointer if any kind of error was encountered.
+*/
+SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
+ if( p->zText ){
+ p->zText[p->nChar] = 0;
+ if( p->useMalloc && p->zText==p->zBase ){
+ if( p->useMalloc==1 ){
+ p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
+ }else{
+ p->zText = sqlite3_malloc(p->nChar+1);
+ }
+ if( p->zText ){
+ memcpy(p->zText, p->zBase, p->nChar+1);
+ }else{
+ setStrAccumError(p, STRACCUM_NOMEM);
+ }
+ }
+ }
+ return p->zText;
+}
+
+/*
+** Reset an StrAccum string. Reclaim all malloced memory.
+*/
+SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum *p){
+ if( p->zText!=p->zBase ){
+ if( p->useMalloc==1 ){
+ sqlite3DbFree(p->db, p->zText);
+ }else{
+ sqlite3_free(p->zText);
+ }
+ }
+ p->zText = 0;
+}
+
+/*
+** Initialize a string accumulator
+*/
+SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx){
+ p->zText = p->zBase = zBase;
+ p->db = 0;
+ p->nChar = 0;
+ p->nAlloc = n;
+ p->mxAlloc = mx;
+ p->useMalloc = 1;
+ p->accError = 0;
+}
+
+/*
+** Print into memory obtained from sqliteMalloc(). Use the internal
+** %-conversion extensions.
+*/
+SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
+ char *z;
+ char zBase[SQLITE_PRINT_BUF_SIZE];
+ StrAccum acc;
+ assert( db!=0 );
+ sqlite3StrAccumInit(&acc, zBase, sizeof(zBase),
+ db->aLimit[SQLITE_LIMIT_LENGTH]);
+ acc.db = db;
+ sqlite3VXPrintf(&acc, SQLITE_PRINTF_INTERNAL, zFormat, ap);
+ z = sqlite3StrAccumFinish(&acc);
+ if( acc.accError==STRACCUM_NOMEM ){
+ db->mallocFailed = 1;
+ }
+ return z;
+}
+
+/*
+** Print into memory obtained from sqliteMalloc(). Use the internal
+** %-conversion extensions.
+*/
+SQLITE_PRIVATE char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
+ va_list ap;
+ char *z;
+ va_start(ap, zFormat);
+ z = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ return z;
+}
+
+/*
+** Like sqlite3MPrintf(), but call sqlite3DbFree() on zStr after formatting
+** the string and before returnning. This routine is intended to be used
+** to modify an existing string. For example:
+**
+** x = sqlite3MPrintf(db, x, "prefix %s suffix", x);
+**
+*/
+SQLITE_PRIVATE char *sqlite3MAppendf(sqlite3 *db, char *zStr, const char *zFormat, ...){
+ va_list ap;
+ char *z;
+ va_start(ap, zFormat);
+ z = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ sqlite3DbFree(db, zStr);
+ return z;
+}
+
+/*
+** Print into memory obtained from sqlite3_malloc(). Omit the internal
+** %-conversion extensions.
+*/
+SQLITE_API char *sqlite3_vmprintf(const char *zFormat, va_list ap){
+ char *z;
+ char zBase[SQLITE_PRINT_BUF_SIZE];
+ StrAccum acc;
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
+ acc.useMalloc = 2;
+ sqlite3VXPrintf(&acc, 0, zFormat, ap);
+ z = sqlite3StrAccumFinish(&acc);
+ return z;
+}
+
+/*
+** Print into memory obtained from sqlite3_malloc()(). Omit the internal
+** %-conversion extensions.
+*/
+SQLITE_API char *sqlite3_mprintf(const char *zFormat, ...){
+ va_list ap;
+ char *z;
+#ifndef SQLITE_OMIT_AUTOINIT
+ if( sqlite3_initialize() ) return 0;
+#endif
+ va_start(ap, zFormat);
+ z = sqlite3_vmprintf(zFormat, ap);
+ va_end(ap);
+ return z;
+}
+
+/*
+** sqlite3_snprintf() works like snprintf() except that it ignores the
+** current locale settings. This is important for SQLite because we
+** are not able to use a "," as the decimal point in place of "." as
+** specified by some locales.
+**
+** Oops: The first two arguments of sqlite3_snprintf() are backwards
+** from the snprintf() standard. Unfortunately, it is too late to change
+** this without breaking compatibility, so we just have to live with the
+** mistake.
+**
+** sqlite3_vsnprintf() is the varargs version.
+*/
+SQLITE_API char *sqlite3_vsnprintf(int n, char *zBuf, const char *zFormat, va_list ap){
+ StrAccum acc;
+ if( n<=0 ) return zBuf;
+ sqlite3StrAccumInit(&acc, zBuf, n, 0);
+ acc.useMalloc = 0;
+ sqlite3VXPrintf(&acc, 0, zFormat, ap);
+ return sqlite3StrAccumFinish(&acc);
+}
+SQLITE_API char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
+ char *z;
+ va_list ap;
+ va_start(ap,zFormat);
+ z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
+ va_end(ap);
+ return z;
+}
+
+/*
+** This is the routine that actually formats the sqlite3_log() message.
+** We house it in a separate routine from sqlite3_log() to avoid using
+** stack space on small-stack systems when logging is disabled.
+**
+** sqlite3_log() must render into a static buffer. It cannot dynamically
+** allocate memory because it might be called while the memory allocator
+** mutex is held.
+*/
+static void renderLogMsg(int iErrCode, const char *zFormat, va_list ap){
+ StrAccum acc; /* String accumulator */
+ char zMsg[SQLITE_PRINT_BUF_SIZE*3]; /* Complete log message */
+
+ sqlite3StrAccumInit(&acc, zMsg, sizeof(zMsg), 0);
+ acc.useMalloc = 0;
+ sqlite3VXPrintf(&acc, 0, zFormat, ap);
+ sqlite3GlobalConfig.xLog(sqlite3GlobalConfig.pLogArg, iErrCode,
+ sqlite3StrAccumFinish(&acc));
+}
+
+/*
+** Format and write a message to the log if logging is enabled.
+*/
+SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...){
+ va_list ap; /* Vararg list */
+ if( sqlite3GlobalConfig.xLog ){
+ va_start(ap, zFormat);
+ renderLogMsg(iErrCode, zFormat, ap);
+ va_end(ap);
+ }
+}
+
+#if defined(SQLITE_DEBUG)
+/*
+** A version of printf() that understands %lld. Used for debugging.
+** The printf() built into some versions of windows does not understand %lld
+** and segfaults if you give it a long long int.
+*/
+SQLITE_PRIVATE void sqlite3DebugPrintf(const char *zFormat, ...){
+ va_list ap;
+ StrAccum acc;
+ char zBuf[500];
+ sqlite3StrAccumInit(&acc, zBuf, sizeof(zBuf), 0);
+ acc.useMalloc = 0;
+ va_start(ap,zFormat);
+ sqlite3VXPrintf(&acc, 0, zFormat, ap);
+ va_end(ap);
+ sqlite3StrAccumFinish(&acc);
+ fprintf(stdout,"%s", zBuf);
+ fflush(stdout);
+}
+#endif
+
+/*
+** variable-argument wrapper around sqlite3VXPrintf().
+*/
+SQLITE_PRIVATE void sqlite3XPrintf(StrAccum *p, u32 bFlags, const char *zFormat, ...){
+ va_list ap;
+ va_start(ap,zFormat);
+ sqlite3VXPrintf(p, bFlags, zFormat, ap);
+ va_end(ap);
+}
+
+/************** End of printf.c **********************************************/
+/************** Begin file random.c ******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code to implement a pseudo-random number
+** generator (PRNG) for SQLite.
+**
+** Random numbers are used by some of the database backends in order
+** to generate random integer keys for tables or random filenames.
+*/
+
+
+/* All threads share a single random number generator.
+** This structure is the current state of the generator.
+*/
+static SQLITE_WSD struct sqlite3PrngType {
+ unsigned char isInit; /* True if initialized */
+ unsigned char i, j; /* State variables */
+ unsigned char s[256]; /* State variables */
+} sqlite3Prng;
+
+/*
+** Return N random bytes.
+*/
+SQLITE_API void sqlite3_randomness(int N, void *pBuf){
+ unsigned char t;
+ unsigned char *zBuf = pBuf;
+
+ /* The "wsdPrng" macro will resolve to the pseudo-random number generator
+ ** state vector. If writable static data is unsupported on the target,
+ ** we have to locate the state vector at run-time. In the more common
+ ** case where writable static data is supported, wsdPrng can refer directly
+ ** to the "sqlite3Prng" state vector declared above.
+ */
+#ifdef SQLITE_OMIT_WSD
+ struct sqlite3PrngType *p = &GLOBAL(struct sqlite3PrngType, sqlite3Prng);
+# define wsdPrng p[0]
+#else
+# define wsdPrng sqlite3Prng
+#endif
+
+#if SQLITE_THREADSAFE
+ sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
+ sqlite3_mutex_enter(mutex);
+#endif
+
+ if( N<=0 ){
+ wsdPrng.isInit = 0;
+ sqlite3_mutex_leave(mutex);
+ return;
+ }
+
+ /* Initialize the state of the random number generator once,
+ ** the first time this routine is called. The seed value does
+ ** not need to contain a lot of randomness since we are not
+ ** trying to do secure encryption or anything like that...
+ **
+ ** Nothing in this file or anywhere else in SQLite does any kind of
+ ** encryption. The RC4 algorithm is being used as a PRNG (pseudo-random
+ ** number generator) not as an encryption device.
+ */
+ if( !wsdPrng.isInit ){
+ int i;
+ char k[256];
+ wsdPrng.j = 0;
+ wsdPrng.i = 0;
+ sqlite3OsRandomness(sqlite3_vfs_find(0), 256, k);
+ for(i=0; i<256; i++){
+ wsdPrng.s[i] = (u8)i;
+ }
+ for(i=0; i<256; i++){
+ wsdPrng.j += wsdPrng.s[i] + k[i];
+ t = wsdPrng.s[wsdPrng.j];
+ wsdPrng.s[wsdPrng.j] = wsdPrng.s[i];
+ wsdPrng.s[i] = t;
+ }
+ wsdPrng.isInit = 1;
+ }
+
+ assert( N>0 );
+ do{
+ wsdPrng.i++;
+ t = wsdPrng.s[wsdPrng.i];
+ wsdPrng.j += t;
+ wsdPrng.s[wsdPrng.i] = wsdPrng.s[wsdPrng.j];
+ wsdPrng.s[wsdPrng.j] = t;
+ t += wsdPrng.s[wsdPrng.i];
+ *(zBuf++) = wsdPrng.s[t];
+ }while( --N );
+ sqlite3_mutex_leave(mutex);
+}
+
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+/*
+** For testing purposes, we sometimes want to preserve the state of
+** PRNG and restore the PRNG to its saved state at a later time, or
+** to reset the PRNG to its initial state. These routines accomplish
+** those tasks.
+**
+** The sqlite3_test_control() interface calls these routines to
+** control the PRNG.
+*/
+static SQLITE_WSD struct sqlite3PrngType sqlite3SavedPrng;
+SQLITE_PRIVATE void sqlite3PrngSaveState(void){
+ memcpy(
+ &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+ &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+ sizeof(sqlite3Prng)
+ );
+}
+SQLITE_PRIVATE void sqlite3PrngRestoreState(void){
+ memcpy(
+ &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
+ &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
+ sizeof(sqlite3Prng)
+ );
+}
+#endif /* SQLITE_OMIT_BUILTIN_TEST */
+
+/************** End of random.c **********************************************/
+/************** Begin file utf.c *********************************************/
+/*
+** 2004 April 13
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains routines used to translate between UTF-8,
+** UTF-16, UTF-16BE, and UTF-16LE.
+**
+** Notes on UTF-8:
+**
+** Byte-0 Byte-1 Byte-2 Byte-3 Value
+** 0xxxxxxx 00000000 00000000 0xxxxxxx
+** 110yyyyy 10xxxxxx 00000000 00000yyy yyxxxxxx
+** 1110zzzz 10yyyyyy 10xxxxxx 00000000 zzzzyyyy yyxxxxxx
+** 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx 000uuuuu zzzzyyyy yyxxxxxx
+**
+**
+** Notes on UTF-16: (with wwww+1==uuuuu)
+**
+** Word-0 Word-1 Value
+** 110110ww wwzzzzyy 110111yy yyxxxxxx 000uuuuu zzzzyyyy yyxxxxxx
+** zzzzyyyy yyxxxxxx 00000000 zzzzyyyy yyxxxxxx
+**
+**
+** BOM or Byte Order Mark:
+** 0xff 0xfe little-endian utf-16 follows
+** 0xfe 0xff big-endian utf-16 follows
+**
+*/
+/* #include */
+
+#ifndef SQLITE_AMALGAMATION
+/*
+** The following constant value is used by the SQLITE_BIGENDIAN and
+** SQLITE_LITTLEENDIAN macros.
+*/
+SQLITE_PRIVATE const int sqlite3one = 1;
+#endif /* SQLITE_AMALGAMATION */
+
+/*
+** This lookup table is used to help decode the first byte of
+** a multi-byte UTF8 character.
+*/
+static const unsigned char sqlite3Utf8Trans1[] = {
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,
+};
+
+
+#define WRITE_UTF8(zOut, c) { \
+ if( c<0x00080 ){ \
+ *zOut++ = (u8)(c&0xFF); \
+ } \
+ else if( c<0x00800 ){ \
+ *zOut++ = 0xC0 + (u8)((c>>6)&0x1F); \
+ *zOut++ = 0x80 + (u8)(c & 0x3F); \
+ } \
+ else if( c<0x10000 ){ \
+ *zOut++ = 0xE0 + (u8)((c>>12)&0x0F); \
+ *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); \
+ *zOut++ = 0x80 + (u8)(c & 0x3F); \
+ }else{ \
+ *zOut++ = 0xF0 + (u8)((c>>18) & 0x07); \
+ *zOut++ = 0x80 + (u8)((c>>12) & 0x3F); \
+ *zOut++ = 0x80 + (u8)((c>>6) & 0x3F); \
+ *zOut++ = 0x80 + (u8)(c & 0x3F); \
+ } \
+}
+
+#define WRITE_UTF16LE(zOut, c) { \
+ if( c<=0xFFFF ){ \
+ *zOut++ = (u8)(c&0x00FF); \
+ *zOut++ = (u8)((c>>8)&0x00FF); \
+ }else{ \
+ *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \
+ *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03)); \
+ *zOut++ = (u8)(c&0x00FF); \
+ *zOut++ = (u8)(0x00DC + ((c>>8)&0x03)); \
+ } \
+}
+
+#define WRITE_UTF16BE(zOut, c) { \
+ if( c<=0xFFFF ){ \
+ *zOut++ = (u8)((c>>8)&0x00FF); \
+ *zOut++ = (u8)(c&0x00FF); \
+ }else{ \
+ *zOut++ = (u8)(0x00D8 + (((c-0x10000)>>18)&0x03)); \
+ *zOut++ = (u8)(((c>>10)&0x003F) + (((c-0x10000)>>10)&0x00C0)); \
+ *zOut++ = (u8)(0x00DC + ((c>>8)&0x03)); \
+ *zOut++ = (u8)(c&0x00FF); \
+ } \
+}
+
+#define READ_UTF16LE(zIn, TERM, c){ \
+ c = (*zIn++); \
+ c += ((*zIn++)<<8); \
+ if( c>=0xD800 && c<0xE000 && TERM ){ \
+ int c2 = (*zIn++); \
+ c2 += ((*zIn++)<<8); \
+ c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \
+ } \
+}
+
+#define READ_UTF16BE(zIn, TERM, c){ \
+ c = ((*zIn++)<<8); \
+ c += (*zIn++); \
+ if( c>=0xD800 && c<0xE000 && TERM ){ \
+ int c2 = ((*zIn++)<<8); \
+ c2 += (*zIn++); \
+ c = (c2&0x03FF) + ((c&0x003F)<<10) + (((c&0x03C0)+0x0040)<<10); \
+ } \
+}
+
+/*
+** Translate a single UTF-8 character. Return the unicode value.
+**
+** During translation, assume that the byte that zTerm points
+** is a 0x00.
+**
+** Write a pointer to the next unread byte back into *pzNext.
+**
+** Notes On Invalid UTF-8:
+**
+** * This routine never allows a 7-bit character (0x00 through 0x7f) to
+** be encoded as a multi-byte character. Any multi-byte character that
+** attempts to encode a value between 0x00 and 0x7f is rendered as 0xfffd.
+**
+** * This routine never allows a UTF16 surrogate value to be encoded.
+** If a multi-byte character attempts to encode a value between
+** 0xd800 and 0xe000 then it is rendered as 0xfffd.
+**
+** * Bytes in the range of 0x80 through 0xbf which occur as the first
+** byte of a character are interpreted as single-byte characters
+** and rendered as themselves even though they are technically
+** invalid characters.
+**
+** * This routine accepts an infinite number of different UTF8 encodings
+** for unicode values 0x80 and greater. It do not change over-length
+** encodings to 0xfffd as some systems recommend.
+*/
+#define READ_UTF8(zIn, zTerm, c) \
+ c = *(zIn++); \
+ if( c>=0xc0 ){ \
+ c = sqlite3Utf8Trans1[c-0xc0]; \
+ while( zIn!=zTerm && (*zIn & 0xc0)==0x80 ){ \
+ c = (c<<6) + (0x3f & *(zIn++)); \
+ } \
+ if( c<0x80 \
+ || (c&0xFFFFF800)==0xD800 \
+ || (c&0xFFFFFFFE)==0xFFFE ){ c = 0xFFFD; } \
+ }
+SQLITE_PRIVATE u32 sqlite3Utf8Read(
+ const unsigned char **pz /* Pointer to string from which to read char */
+){
+ unsigned int c;
+
+ /* Same as READ_UTF8() above but without the zTerm parameter.
+ ** For this routine, we assume the UTF8 string is always zero-terminated.
+ */
+ c = *((*pz)++);
+ if( c>=0xc0 ){
+ c = sqlite3Utf8Trans1[c-0xc0];
+ while( (*(*pz) & 0xc0)==0x80 ){
+ c = (c<<6) + (0x3f & *((*pz)++));
+ }
+ if( c<0x80
+ || (c&0xFFFFF800)==0xD800
+ || (c&0xFFFFFFFE)==0xFFFE ){ c = 0xFFFD; }
+ }
+ return c;
+}
+
+
+
+
+/*
+** If the TRANSLATE_TRACE macro is defined, the value of each Mem is
+** printed on stderr on the way into and out of sqlite3VdbeMemTranslate().
+*/
+/* #define TRANSLATE_TRACE 1 */
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** This routine transforms the internal text encoding used by pMem to
+** desiredEnc. It is an error if the string is already of the desired
+** encoding, or if *pMem does not contain a string value.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
+ int len; /* Maximum length of output string in bytes */
+ unsigned char *zOut; /* Output buffer */
+ unsigned char *zIn; /* Input iterator */
+ unsigned char *zTerm; /* End of input */
+ unsigned char *z; /* Output iterator */
+ unsigned int c;
+
+ assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
+ assert( pMem->flags&MEM_Str );
+ assert( pMem->enc!=desiredEnc );
+ assert( pMem->enc!=0 );
+ assert( pMem->n>=0 );
+
+#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
+ {
+ char zBuf[100];
+ sqlite3VdbeMemPrettyPrint(pMem, zBuf);
+ fprintf(stderr, "INPUT: %s\n", zBuf);
+ }
+#endif
+
+ /* If the translation is between UTF-16 little and big endian, then
+ ** all that is required is to swap the byte order. This case is handled
+ ** differently from the others.
+ */
+ if( pMem->enc!=SQLITE_UTF8 && desiredEnc!=SQLITE_UTF8 ){
+ u8 temp;
+ int rc;
+ rc = sqlite3VdbeMemMakeWriteable(pMem);
+ if( rc!=SQLITE_OK ){
+ assert( rc==SQLITE_NOMEM );
+ return SQLITE_NOMEM;
+ }
+ zIn = (u8*)pMem->z;
+ zTerm = &zIn[pMem->n&~1];
+ while( zInenc = desiredEnc;
+ goto translate_out;
+ }
+
+ /* Set len to the maximum number of bytes required in the output buffer. */
+ if( desiredEnc==SQLITE_UTF8 ){
+ /* When converting from UTF-16, the maximum growth results from
+ ** translating a 2-byte character to a 4-byte UTF-8 character.
+ ** A single byte is required for the output string
+ ** nul-terminator.
+ */
+ pMem->n &= ~1;
+ len = pMem->n * 2 + 1;
+ }else{
+ /* When converting from UTF-8 to UTF-16 the maximum growth is caused
+ ** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16
+ ** character. Two bytes are required in the output buffer for the
+ ** nul-terminator.
+ */
+ len = pMem->n * 2 + 2;
+ }
+
+ /* Set zIn to point at the start of the input buffer and zTerm to point 1
+ ** byte past the end.
+ **
+ ** Variable zOut is set to point at the output buffer, space obtained
+ ** from sqlite3_malloc().
+ */
+ zIn = (u8*)pMem->z;
+ zTerm = &zIn[pMem->n];
+ zOut = sqlite3DbMallocRaw(pMem->db, len);
+ if( !zOut ){
+ return SQLITE_NOMEM;
+ }
+ z = zOut;
+
+ if( pMem->enc==SQLITE_UTF8 ){
+ if( desiredEnc==SQLITE_UTF16LE ){
+ /* UTF-8 -> UTF-16 Little-endian */
+ while( zIn UTF-16 Big-endian */
+ while( zInn = (int)(z - zOut);
+ *z++ = 0;
+ }else{
+ assert( desiredEnc==SQLITE_UTF8 );
+ if( pMem->enc==SQLITE_UTF16LE ){
+ /* UTF-16 Little-endian -> UTF-8 */
+ while( zIn UTF-8 */
+ while( zInn = (int)(z - zOut);
+ }
+ *z = 0;
+ assert( (pMem->n+(desiredEnc==SQLITE_UTF8?1:2))<=len );
+
+ sqlite3VdbeMemRelease(pMem);
+ pMem->flags &= ~(MEM_Static|MEM_Dyn|MEM_Ephem);
+ pMem->enc = desiredEnc;
+ pMem->flags |= (MEM_Term);
+ pMem->z = (char*)zOut;
+ pMem->zMalloc = pMem->z;
+
+translate_out:
+#if defined(TRANSLATE_TRACE) && defined(SQLITE_DEBUG)
+ {
+ char zBuf[100];
+ sqlite3VdbeMemPrettyPrint(pMem, zBuf);
+ fprintf(stderr, "OUTPUT: %s\n", zBuf);
+ }
+#endif
+ return SQLITE_OK;
+}
+
+/*
+** This routine checks for a byte-order mark at the beginning of the
+** UTF-16 string stored in *pMem. If one is present, it is removed and
+** the encoding of the Mem adjusted. This routine does not do any
+** byte-swapping, it just sets Mem.enc appropriately.
+**
+** The allocation (static, dynamic etc.) and encoding of the Mem may be
+** changed by this function.
+*/
+SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem){
+ int rc = SQLITE_OK;
+ u8 bom = 0;
+
+ assert( pMem->n>=0 );
+ if( pMem->n>1 ){
+ u8 b1 = *(u8 *)pMem->z;
+ u8 b2 = *(((u8 *)pMem->z) + 1);
+ if( b1==0xFE && b2==0xFF ){
+ bom = SQLITE_UTF16BE;
+ }
+ if( b1==0xFF && b2==0xFE ){
+ bom = SQLITE_UTF16LE;
+ }
+ }
+
+ if( bom ){
+ rc = sqlite3VdbeMemMakeWriteable(pMem);
+ if( rc==SQLITE_OK ){
+ pMem->n -= 2;
+ memmove(pMem->z, &pMem->z[2], pMem->n);
+ pMem->z[pMem->n] = '\0';
+ pMem->z[pMem->n+1] = '\0';
+ pMem->flags |= MEM_Term;
+ pMem->enc = bom;
+ }
+ }
+ return rc;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+/*
+** pZ is a UTF-8 encoded unicode string. If nByte is less than zero,
+** return the number of unicode characters in pZ up to (but not including)
+** the first 0x00 byte. If nByte is not less than zero, return the
+** number of unicode characters in the first nByte of pZ (or up to
+** the first 0x00, whichever comes first).
+*/
+SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *zIn, int nByte){
+ int r = 0;
+ const u8 *z = (const u8*)zIn;
+ const u8 *zTerm;
+ if( nByte>=0 ){
+ zTerm = &z[nByte];
+ }else{
+ zTerm = (const u8*)(-1);
+ }
+ assert( z<=zTerm );
+ while( *z!=0 && zmallocFailed ){
+ sqlite3VdbeMemRelease(&m);
+ m.z = 0;
+ }
+ assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
+ assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
+ assert( m.z || db->mallocFailed );
+ return m.z;
+}
+
+/*
+** zIn is a UTF-16 encoded unicode string at least nChar characters long.
+** Return the number of bytes in the first nChar unicode characters
+** in pZ. nChar must be non-negative.
+*/
+SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *zIn, int nChar){
+ int c;
+ unsigned char const *z = zIn;
+ int n = 0;
+
+ if( SQLITE_UTF16NATIVE==SQLITE_UTF16BE ){
+ while( n0 && n<=4 );
+ z[0] = 0;
+ z = zBuf;
+ c = sqlite3Utf8Read((const u8**)&z);
+ t = i;
+ if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
+ if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
+ assert( c==t );
+ assert( (z-zBuf)==n );
+ }
+ for(i=0; i<0x00110000; i++){
+ if( i>=0xD800 && i<0xE000 ) continue;
+ z = zBuf;
+ WRITE_UTF16LE(z, i);
+ n = (int)(z-zBuf);
+ assert( n>0 && n<=4 );
+ z[0] = 0;
+ z = zBuf;
+ READ_UTF16LE(z, 1, c);
+ assert( c==i );
+ assert( (z-zBuf)==n );
+ }
+ for(i=0; i<0x00110000; i++){
+ if( i>=0xD800 && i<0xE000 ) continue;
+ z = zBuf;
+ WRITE_UTF16BE(z, i);
+ n = (int)(z-zBuf);
+ assert( n>0 && n<=4 );
+ z[0] = 0;
+ z = zBuf;
+ READ_UTF16BE(z, 1, c);
+ assert( c==i );
+ assert( (z-zBuf)==n );
+ }
+}
+#endif /* SQLITE_TEST */
+#endif /* SQLITE_OMIT_UTF16 */
+
+/************** End of utf.c *************************************************/
+/************** Begin file util.c ********************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** Utility functions used throughout sqlite.
+**
+** This file contains functions for allocating memory, comparing
+** strings, and stuff like that.
+**
+*/
+/* #include */
+#ifdef SQLITE_HAVE_ISNAN
+# include
+#endif
+
+/*
+** Routine needed to support the testcase() macro.
+*/
+#ifdef SQLITE_COVERAGE_TEST
+SQLITE_PRIVATE void sqlite3Coverage(int x){
+ static unsigned dummy = 0;
+ dummy += (unsigned)x;
+}
+#endif
+
+/*
+** Give a callback to the test harness that can be used to simulate faults
+** in places where it is difficult or expensive to do so purely by means
+** of inputs.
+**
+** The intent of the integer argument is to let the fault simulator know
+** which of multiple sqlite3FaultSim() calls has been hit.
+**
+** Return whatever integer value the test callback returns, or return
+** SQLITE_OK if no test callback is installed.
+*/
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+SQLITE_PRIVATE int sqlite3FaultSim(int iTest){
+ int (*xCallback)(int) = sqlite3GlobalConfig.xTestCallback;
+ return xCallback ? xCallback(iTest) : SQLITE_OK;
+}
+#endif
+
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** Return true if the floating point value is Not a Number (NaN).
+**
+** Use the math library isnan() function if compiled with SQLITE_HAVE_ISNAN.
+** Otherwise, we have our own implementation that works on most systems.
+*/
+SQLITE_PRIVATE int sqlite3IsNaN(double x){
+ int rc; /* The value return */
+#if !defined(SQLITE_HAVE_ISNAN)
+ /*
+ ** Systems that support the isnan() library function should probably
+ ** make use of it by compiling with -DSQLITE_HAVE_ISNAN. But we have
+ ** found that many systems do not have a working isnan() function so
+ ** this implementation is provided as an alternative.
+ **
+ ** This NaN test sometimes fails if compiled on GCC with -ffast-math.
+ ** On the other hand, the use of -ffast-math comes with the following
+ ** warning:
+ **
+ ** This option [-ffast-math] should never be turned on by any
+ ** -O option since it can result in incorrect output for programs
+ ** which depend on an exact implementation of IEEE or ISO
+ ** rules/specifications for math functions.
+ **
+ ** Under MSVC, this NaN test may fail if compiled with a floating-
+ ** point precision mode other than /fp:precise. From the MSDN
+ ** documentation:
+ **
+ ** The compiler [with /fp:precise] will properly handle comparisons
+ ** involving NaN. For example, x != x evaluates to true if x is NaN
+ ** ...
+ */
+#ifdef __FAST_MATH__
+# error SQLite will not work correctly with the -ffast-math option of GCC.
+#endif
+ volatile double y = x;
+ volatile double z = y;
+ rc = (y!=z);
+#else /* if defined(SQLITE_HAVE_ISNAN) */
+ rc = isnan(x);
+#endif /* SQLITE_HAVE_ISNAN */
+ testcase( rc );
+ return rc;
+}
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+
+/*
+** Compute a string length that is limited to what can be stored in
+** lower 30 bits of a 32-bit signed integer.
+**
+** The value returned will never be negative. Nor will it ever be greater
+** than the actual length of the string. For very long strings (greater
+** than 1GiB) the value returned might be less than the true string length.
+*/
+SQLITE_PRIVATE int sqlite3Strlen30(const char *z){
+ const char *z2 = z;
+ if( z==0 ) return 0;
+ while( *z2 ){ z2++; }
+ return 0x3fffffff & (int)(z2 - z);
+}
+
+/*
+** Set the most recent error code and error string for the sqlite
+** handle "db". The error code is set to "err_code".
+**
+** If it is not NULL, string zFormat specifies the format of the
+** error string in the style of the printf functions: The following
+** format characters are allowed:
+**
+** %s Insert a string
+** %z A string that should be freed after use
+** %d Insert an integer
+** %T Insert a token
+** %S Insert the first element of a SrcList
+**
+** zFormat and any string tokens that follow it are assumed to be
+** encoded in UTF-8.
+**
+** To clear the most recent error for sqlite handle "db", sqlite3Error
+** should be called with err_code set to SQLITE_OK and zFormat set
+** to NULL.
+*/
+SQLITE_PRIVATE void sqlite3Error(sqlite3 *db, int err_code, const char *zFormat, ...){
+ assert( db!=0 );
+ db->errCode = err_code;
+ if( zFormat && (db->pErr || (db->pErr = sqlite3ValueNew(db))!=0) ){
+ char *z;
+ va_list ap;
+ va_start(ap, zFormat);
+ z = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
+ }else if( db->pErr ){
+ sqlite3ValueSetNull(db->pErr);
+ }
+}
+
+/*
+** Add an error message to pParse->zErrMsg and increment pParse->nErr.
+** The following formatting characters are allowed:
+**
+** %s Insert a string
+** %z A string that should be freed after use
+** %d Insert an integer
+** %T Insert a token
+** %S Insert the first element of a SrcList
+**
+** This function should be used to report any error that occurs whilst
+** compiling an SQL statement (i.e. within sqlite3_prepare()). The
+** last thing the sqlite3_prepare() function does is copy the error
+** stored by this function into the database handle using sqlite3Error().
+** Function sqlite3Error() should be used during statement execution
+** (sqlite3_step() etc.).
+*/
+SQLITE_PRIVATE void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
+ char *zMsg;
+ va_list ap;
+ sqlite3 *db = pParse->db;
+ va_start(ap, zFormat);
+ zMsg = sqlite3VMPrintf(db, zFormat, ap);
+ va_end(ap);
+ if( db->suppressErr ){
+ sqlite3DbFree(db, zMsg);
+ }else{
+ pParse->nErr++;
+ sqlite3DbFree(db, pParse->zErrMsg);
+ pParse->zErrMsg = zMsg;
+ pParse->rc = SQLITE_ERROR;
+ }
+}
+
+/*
+** Convert an SQL-style quoted string into a normal string by removing
+** the quote characters. The conversion is done in-place. If the
+** input does not begin with a quote character, then this routine
+** is a no-op.
+**
+** The input string must be zero-terminated. A new zero-terminator
+** is added to the dequoted string.
+**
+** The return value is -1 if no dequoting occurs or the length of the
+** dequoted string, exclusive of the zero terminator, if dequoting does
+** occur.
+**
+** 2002-Feb-14: This routine is extended to remove MS-Access style
+** brackets from around identifers. For example: "[a-b-c]" becomes
+** "a-b-c".
+*/
+SQLITE_PRIVATE int sqlite3Dequote(char *z){
+ char quote;
+ int i, j;
+ if( z==0 ) return -1;
+ quote = z[0];
+ switch( quote ){
+ case '\'': break;
+ case '"': break;
+ case '`': break; /* For MySQL compatibility */
+ case '[': quote = ']'; break; /* For MS SqlServer compatibility */
+ default: return -1;
+ }
+ for(i=1, j=0;; i++){
+ assert( z[i] );
+ if( z[i]==quote ){
+ if( z[i+1]==quote ){
+ z[j++] = quote;
+ i++;
+ }else{
+ break;
+ }
+ }else{
+ z[j++] = z[i];
+ }
+ }
+ z[j] = 0;
+ return j;
+}
+
+/* Convenient short-hand */
+#define UpperToLower sqlite3UpperToLower
+
+/*
+** Some systems have stricmp(). Others have strcasecmp(). Because
+** there is no consistency, we will define our own.
+**
+** IMPLEMENTATION-OF: R-30243-02494 The sqlite3_stricmp() and
+** sqlite3_strnicmp() APIs allow applications and extensions to compare
+** the contents of two buffers containing UTF-8 strings in a
+** case-independent fashion, using the same definition of "case
+** independence" that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_stricmp(const char *zLeft, const char *zRight){
+ register unsigned char *a, *b;
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ while( *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+ return UpperToLower[*a] - UpperToLower[*b];
+}
+SQLITE_API int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
+ register unsigned char *a, *b;
+ a = (unsigned char *)zLeft;
+ b = (unsigned char *)zRight;
+ while( N-- > 0 && *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }
+ return N<0 ? 0 : UpperToLower[*a] - UpperToLower[*b];
+}
+
+/*
+** The string z[] is an text representation of a real number.
+** Convert this string to a double and write it into *pResult.
+**
+** The string z[] is length bytes in length (bytes, not characters) and
+** uses the encoding enc. The string is not necessarily zero-terminated.
+**
+** Return TRUE if the result is a valid real number (or integer) and FALSE
+** if the string is empty or contains extraneous text. Valid numbers
+** are in one of these formats:
+**
+** [+-]digits[E[+-]digits]
+** [+-]digits.[digits][E[+-]digits]
+** [+-].digits[E[+-]digits]
+**
+** Leading and trailing whitespace is ignored for the purpose of determining
+** validity.
+**
+** If some prefix of the input string is a valid number, this routine
+** returns FALSE but it still converts the prefix and writes the result
+** into *pResult.
+*/
+SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ int incr;
+ const char *zEnd = z + length;
+ /* sign * significand * (10 ^ (esign * exponent)) */
+ int sign = 1; /* sign of significand */
+ i64 s = 0; /* significand */
+ int d = 0; /* adjust exponent for shifting decimal point */
+ int esign = 1; /* sign of exponent */
+ int e = 0; /* exponent */
+ int eValid = 1; /* True exponent is either not used or is well-formed */
+ double result;
+ int nDigits = 0;
+ int nonNum = 0;
+
+ assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+ *pResult = 0.0; /* Default return value, in case of an error */
+
+ if( enc==SQLITE_UTF8 ){
+ incr = 1;
+ }else{
+ int i;
+ incr = 2;
+ assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+ for(i=3-enc; i=zEnd ) return 0;
+
+ /* get sign of significand */
+ if( *z=='-' ){
+ sign = -1;
+ z+=incr;
+ }else if( *z=='+' ){
+ z+=incr;
+ }
+
+ /* skip leading zeroes */
+ while( z=zEnd ) goto do_atof_calc;
+
+ /* if decimal point is present */
+ if( *z=='.' ){
+ z+=incr;
+ /* copy digits from after decimal to significand
+ ** (decrease exponent by d to shift decimal right) */
+ while( z=zEnd ) goto do_atof_calc;
+
+ /* if exponent is present */
+ if( *z=='e' || *z=='E' ){
+ z+=incr;
+ eValid = 0;
+ if( z>=zEnd ) goto do_atof_calc;
+ /* get sign of exponent */
+ if( *z=='-' ){
+ esign = -1;
+ z+=incr;
+ }else if( *z=='+' ){
+ z+=incr;
+ }
+ /* copy digits to exponent */
+ while( z0 ){
+ while( s<(LARGEST_INT64/10) && e>0 ) e--,s*=10;
+ }else{
+ while( !(s%10) && e>0 ) e--,s/=10;
+ }
+
+ /* adjust the sign of significand */
+ s = sign<0 ? -s : s;
+
+ /* if exponent, scale significand as appropriate
+ ** and store in result. */
+ if( e ){
+ LONGDOUBLE_TYPE scale = 1.0;
+ /* attempt to handle extremely small/large numbers better */
+ if( e>307 && e<342 ){
+ while( e%308 ) { scale *= 1.0e+1; e -= 1; }
+ if( esign<0 ){
+ result = s / scale;
+ result /= 1.0e+308;
+ }else{
+ result = s * scale;
+ result *= 1.0e+308;
+ }
+ }else if( e>=342 ){
+ if( esign<0 ){
+ result = 0.0*s;
+ }else{
+ result = 1e308*1e308*s; /* Infinity */
+ }
+ }else{
+ /* 1.0e+22 is the largest power of 10 than can be
+ ** represented exactly. */
+ while( e%22 ) { scale *= 1.0e+1; e -= 1; }
+ while( e>0 ) { scale *= 1.0e+22; e -= 22; }
+ if( esign<0 ){
+ result = s / scale;
+ }else{
+ result = s * scale;
+ }
+ }
+ } else {
+ result = (double)s;
+ }
+ }
+
+ /* store the result */
+ *pResult = result;
+
+ /* return true if number and no extra non-whitespace chracters after */
+ return z>=zEnd && nDigits>0 && eValid && nonNum==0;
+#else
+ return !sqlite3Atoi64(z, pResult, length, enc);
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+}
+
+/*
+** Compare the 19-character string zNum against the text representation
+** value 2^63: 9223372036854775808. Return negative, zero, or positive
+** if zNum is less than, equal to, or greater than the string.
+** Note that zNum must contain exactly 19 characters.
+**
+** Unlike memcmp() this routine is guaranteed to return the difference
+** in the values of the last digit if the only difference is in the
+** last digit. So, for example,
+**
+** compare2pow63("9223372036854775800", 1)
+**
+** will return -8.
+*/
+static int compare2pow63(const char *zNum, int incr){
+ int c = 0;
+ int i;
+ /* 012345678901234567 */
+ const char *pow63 = "922337203685477580";
+ for(i=0; c==0 && i<18; i++){
+ c = (zNum[i*incr]-pow63[i])*10;
+ }
+ if( c==0 ){
+ c = zNum[18*incr] - '8';
+ testcase( c==(-1) );
+ testcase( c==0 );
+ testcase( c==(+1) );
+ }
+ return c;
+}
+
+
+/*
+** Convert zNum to a 64-bit signed integer.
+**
+** If the zNum value is representable as a 64-bit twos-complement
+** integer, then write that value into *pNum and return 0.
+**
+** If zNum is exactly 9223372036854775808, return 2. This special
+** case is broken out because while 9223372036854775808 cannot be a
+** signed 64-bit integer, its negative -9223372036854775808 can be.
+**
+** If zNum is too big for a 64-bit integer and is not
+** 9223372036854775808 or if zNum contains any non-numeric text,
+** then return 1.
+**
+** length is the number of bytes in the string (bytes, not characters).
+** The string is not necessarily zero-terminated. The encoding is
+** given by enc.
+*/
+SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){
+ int incr;
+ u64 u = 0;
+ int neg = 0; /* assume positive */
+ int i;
+ int c = 0;
+ int nonNum = 0;
+ const char *zStart;
+ const char *zEnd = zNum + length;
+ assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+ if( enc==SQLITE_UTF8 ){
+ incr = 1;
+ }else{
+ incr = 2;
+ assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+ for(i=3-enc; i='0' && c<='9'; i+=incr){
+ u = u*10 + c - '0';
+ }
+ if( u>LARGEST_INT64 ){
+ *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64;
+ }else if( neg ){
+ *pNum = -(i64)u;
+ }else{
+ *pNum = (i64)u;
+ }
+ testcase( i==18 );
+ testcase( i==19 );
+ testcase( i==20 );
+ if( (c!=0 && &zNum[i]19*incr || nonNum ){
+ /* zNum is empty or contains non-numeric text or is longer
+ ** than 19 digits (thus guaranteeing that it is too large) */
+ return 1;
+ }else if( i<19*incr ){
+ /* Less than 19 digits, so we know that it fits in 64 bits */
+ assert( u<=LARGEST_INT64 );
+ return 0;
+ }else{
+ /* zNum is a 19-digit numbers. Compare it against 9223372036854775808. */
+ c = compare2pow63(zNum, incr);
+ if( c<0 ){
+ /* zNum is less than 9223372036854775808 so it fits */
+ assert( u<=LARGEST_INT64 );
+ return 0;
+ }else if( c>0 ){
+ /* zNum is greater than 9223372036854775808 so it overflows */
+ return 1;
+ }else{
+ /* zNum is exactly 9223372036854775808. Fits if negative. The
+ ** special case 2 overflow if positive */
+ assert( u-1==LARGEST_INT64 );
+ return neg ? 0 : 2;
+ }
+ }
+}
+
+/*
+** If zNum represents an integer that will fit in 32-bits, then set
+** *pValue to that integer and return true. Otherwise return false.
+**
+** Any non-numeric characters that following zNum are ignored.
+** This is different from sqlite3Atoi64() which requires the
+** input number to be zero-terminated.
+*/
+SQLITE_PRIVATE int sqlite3GetInt32(const char *zNum, int *pValue){
+ sqlite_int64 v = 0;
+ int i, c;
+ int neg = 0;
+ if( zNum[0]=='-' ){
+ neg = 1;
+ zNum++;
+ }else if( zNum[0]=='+' ){
+ zNum++;
+ }
+ while( zNum[0]=='0' ) zNum++;
+ for(i=0; i<11 && (c = zNum[i] - '0')>=0 && c<=9; i++){
+ v = v*10 + c;
+ }
+
+ /* The longest decimal representation of a 32 bit integer is 10 digits:
+ **
+ ** 1234567890
+ ** 2^31 -> 2147483648
+ */
+ testcase( i==10 );
+ if( i>10 ){
+ return 0;
+ }
+ testcase( v-neg==2147483647 );
+ if( v-neg>2147483647 ){
+ return 0;
+ }
+ if( neg ){
+ v = -v;
+ }
+ *pValue = (int)v;
+ return 1;
+}
+
+/*
+** Return a 32-bit integer value extracted from a string. If the
+** string is not an integer, just return 0.
+*/
+SQLITE_PRIVATE int sqlite3Atoi(const char *z){
+ int x = 0;
+ if( z ) sqlite3GetInt32(z, &x);
+ return x;
+}
+
+/*
+** The variable-length integer encoding is as follows:
+**
+** KEY:
+** A = 0xxxxxxx 7 bits of data and one flag bit
+** B = 1xxxxxxx 7 bits of data and one flag bit
+** C = xxxxxxxx 8 bits of data
+**
+** 7 bits - A
+** 14 bits - BA
+** 21 bits - BBA
+** 28 bits - BBBA
+** 35 bits - BBBBA
+** 42 bits - BBBBBA
+** 49 bits - BBBBBBA
+** 56 bits - BBBBBBBA
+** 64 bits - BBBBBBBBC
+*/
+
+/*
+** Write a 64-bit variable-length integer to memory starting at p[0].
+** The length of data write will be between 1 and 9 bytes. The number
+** of bytes written is returned.
+**
+** A variable-length integer consists of the lower 7 bits of each byte
+** for all bytes that have the 8th bit set and one byte with the 8th
+** bit clear. Except, if we get to the 9th byte, it stores the full
+** 8 bits and is the last byte.
+*/
+SQLITE_PRIVATE int sqlite3PutVarint(unsigned char *p, u64 v){
+ int i, j, n;
+ u8 buf[10];
+ if( v & (((u64)0xff000000)<<32) ){
+ p[8] = (u8)v;
+ v >>= 8;
+ for(i=7; i>=0; i--){
+ p[i] = (u8)((v & 0x7f) | 0x80);
+ v >>= 7;
+ }
+ return 9;
+ }
+ n = 0;
+ do{
+ buf[n++] = (u8)((v & 0x7f) | 0x80);
+ v >>= 7;
+ }while( v!=0 );
+ buf[0] &= 0x7f;
+ assert( n<=9 );
+ for(i=0, j=n-1; j>=0; j--, i++){
+ p[i] = buf[j];
+ }
+ return n;
+}
+
+/*
+** This routine is a faster version of sqlite3PutVarint() that only
+** works for 32-bit positive integers and which is optimized for
+** the common case of small integers. A MACRO version, putVarint32,
+** is provided which inlines the single-byte case. All code should use
+** the MACRO version as this function assumes the single-byte case has
+** already been handled.
+*/
+SQLITE_PRIVATE int sqlite3PutVarint32(unsigned char *p, u32 v){
+#ifndef putVarint32
+ if( (v & ~0x7f)==0 ){
+ p[0] = v;
+ return 1;
+ }
+#endif
+ if( (v & ~0x3fff)==0 ){
+ p[0] = (u8)((v>>7) | 0x80);
+ p[1] = (u8)(v & 0x7f);
+ return 2;
+ }
+ return sqlite3PutVarint(p, v);
+}
+
+/*
+** Bitmasks used by sqlite3GetVarint(). These precomputed constants
+** are defined here rather than simply putting the constant expressions
+** inline in order to work around bugs in the RVT compiler.
+**
+** SLOT_2_0 A mask for (0x7f<<14) | 0x7f
+**
+** SLOT_4_2_0 A mask for (0x7f<<28) | SLOT_2_0
+*/
+#define SLOT_2_0 0x001fc07f
+#define SLOT_4_2_0 0xf01fc07f
+
+
+/*
+** Read a 64-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read. The value is stored in *v.
+*/
+SQLITE_PRIVATE u8 sqlite3GetVarint(const unsigned char *p, u64 *v){
+ u32 a,b,s;
+
+ a = *p;
+ /* a: p0 (unmasked) */
+ if (!(a&0x80))
+ {
+ *v = a;
+ return 1;
+ }
+
+ p++;
+ b = *p;
+ /* b: p1 (unmasked) */
+ if (!(b&0x80))
+ {
+ a &= 0x7f;
+ a = a<<7;
+ a |= b;
+ *v = a;
+ return 2;
+ }
+
+ /* Verify that constants are precomputed correctly */
+ assert( SLOT_2_0 == ((0x7f<<14) | (0x7f)) );
+ assert( SLOT_4_2_0 == ((0xfU<<28) | (0x7f<<14) | (0x7f)) );
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<14 | p2 (unmasked) */
+ if (!(a&0x80))
+ {
+ a &= SLOT_2_0;
+ b &= 0x7f;
+ b = b<<7;
+ a |= b;
+ *v = a;
+ return 3;
+ }
+
+ /* CSE1 from below */
+ a &= SLOT_2_0;
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<14 | p3 (unmasked) */
+ if (!(b&0x80))
+ {
+ b &= SLOT_2_0;
+ /* moved CSE1 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ a = a<<7;
+ a |= b;
+ *v = a;
+ return 4;
+ }
+
+ /* a: p0<<14 | p2 (masked) */
+ /* b: p1<<14 | p3 (unmasked) */
+ /* 1:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+ /* moved CSE1 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ b &= SLOT_2_0;
+ s = a;
+ /* s: p0<<14 | p2 (masked) */
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* we can skip these cause they were (effectively) done above in calc'ing s */
+ /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+ /* b &= (0x7f<<14)|(0x7f); */
+ b = b<<7;
+ a |= b;
+ s = s>>18;
+ *v = ((u64)s)<<32 | a;
+ return 5;
+ }
+
+ /* 2:save off p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+ s = s<<7;
+ s |= b;
+ /* s: p0<<21 | p1<<14 | p2<<7 | p3 (masked) */
+
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<28 | p3<<14 | p5 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* we can skip this cause it was (effectively) done above in calc'ing s */
+ /* b &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
+ a &= SLOT_2_0;
+ a = a<<7;
+ a |= b;
+ s = s>>18;
+ *v = ((u64)s)<<32 | a;
+ return 6;
+ }
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p2<<28 | p4<<14 | p6 (unmasked) */
+ if (!(a&0x80))
+ {
+ a &= SLOT_4_2_0;
+ b &= SLOT_2_0;
+ b = b<<7;
+ a |= b;
+ s = s>>11;
+ *v = ((u64)s)<<32 | a;
+ return 7;
+ }
+
+ /* CSE2 from below */
+ a &= SLOT_2_0;
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p3<<28 | p5<<14 | p7 (unmasked) */
+ if (!(b&0x80))
+ {
+ b &= SLOT_4_2_0;
+ /* moved CSE2 up */
+ /* a &= (0x7f<<14)|(0x7f); */
+ a = a<<7;
+ a |= b;
+ s = s>>4;
+ *v = ((u64)s)<<32 | a;
+ return 8;
+ }
+
+ p++;
+ a = a<<15;
+ a |= *p;
+ /* a: p4<<29 | p6<<15 | p8 (unmasked) */
+
+ /* moved CSE2 up */
+ /* a &= (0x7f<<29)|(0x7f<<15)|(0xff); */
+ b &= SLOT_2_0;
+ b = b<<8;
+ a |= b;
+
+ s = s<<4;
+ b = p[-4];
+ b &= 0x7f;
+ b = b>>3;
+ s |= b;
+
+ *v = ((u64)s)<<32 | a;
+
+ return 9;
+}
+
+/*
+** Read a 32-bit variable-length integer from memory starting at p[0].
+** Return the number of bytes read. The value is stored in *v.
+**
+** If the varint stored in p[0] is larger than can fit in a 32-bit unsigned
+** integer, then set *v to 0xffffffff.
+**
+** A MACRO version, getVarint32, is provided which inlines the
+** single-byte case. All code should use the MACRO version as
+** this function assumes the single-byte case has already been handled.
+*/
+SQLITE_PRIVATE u8 sqlite3GetVarint32(const unsigned char *p, u32 *v){
+ u32 a,b;
+
+ /* The 1-byte case. Overwhelmingly the most common. Handled inline
+ ** by the getVarin32() macro */
+ a = *p;
+ /* a: p0 (unmasked) */
+#ifndef getVarint32
+ if (!(a&0x80))
+ {
+ /* Values between 0 and 127 */
+ *v = a;
+ return 1;
+ }
+#endif
+
+ /* The 2-byte case */
+ p++;
+ b = *p;
+ /* b: p1 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* Values between 128 and 16383 */
+ a &= 0x7f;
+ a = a<<7;
+ *v = a | b;
+ return 2;
+ }
+
+ /* The 3-byte case */
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<14 | p2 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* Values between 16384 and 2097151 */
+ a &= (0x7f<<14)|(0x7f);
+ b &= 0x7f;
+ b = b<<7;
+ *v = a | b;
+ return 3;
+ }
+
+ /* A 32-bit varint is used to store size information in btrees.
+ ** Objects are rarely larger than 2MiB limit of a 3-byte varint.
+ ** A 3-byte varint is sufficient, for example, to record the size
+ ** of a 1048569-byte BLOB or string.
+ **
+ ** We only unroll the first 1-, 2-, and 3- byte cases. The very
+ ** rare larger cases can be handled by the slower 64-bit varint
+ ** routine.
+ */
+#if 1
+ {
+ u64 v64;
+ u8 n;
+
+ p -= 2;
+ n = sqlite3GetVarint(p, &v64);
+ assert( n>3 && n<=9 );
+ if( (v64 & SQLITE_MAX_U32)!=v64 ){
+ *v = 0xffffffff;
+ }else{
+ *v = (u32)v64;
+ }
+ return n;
+ }
+
+#else
+ /* For following code (kept for historical record only) shows an
+ ** unrolling for the 3- and 4-byte varint cases. This code is
+ ** slightly faster, but it is also larger and much harder to test.
+ */
+ p++;
+ b = b<<14;
+ b |= *p;
+ /* b: p1<<14 | p3 (unmasked) */
+ if (!(b&0x80))
+ {
+ /* Values between 2097152 and 268435455 */
+ b &= (0x7f<<14)|(0x7f);
+ a &= (0x7f<<14)|(0x7f);
+ a = a<<7;
+ *v = a | b;
+ return 4;
+ }
+
+ p++;
+ a = a<<14;
+ a |= *p;
+ /* a: p0<<28 | p2<<14 | p4 (unmasked) */
+ if (!(a&0x80))
+ {
+ /* Values between 268435456 and 34359738367 */
+ a &= SLOT_4_2_0;
+ b &= SLOT_4_2_0;
+ b = b<<7;
+ *v = a | b;
+ return 5;
+ }
+
+ /* We can only reach this point when reading a corrupt database
+ ** file. In that case we are not in any hurry. Use the (relatively
+ ** slow) general-purpose sqlite3GetVarint() routine to extract the
+ ** value. */
+ {
+ u64 v64;
+ u8 n;
+
+ p -= 4;
+ n = sqlite3GetVarint(p, &v64);
+ assert( n>5 && n<=9 );
+ *v = (u32)v64;
+ return n;
+ }
+#endif
+}
+
+/*
+** Return the number of bytes that will be needed to store the given
+** 64-bit integer.
+*/
+SQLITE_PRIVATE int sqlite3VarintLen(u64 v){
+ int i = 0;
+ do{
+ i++;
+ v >>= 7;
+ }while( v!=0 && ALWAYS(i<9) );
+ return i;
+}
+
+
+/*
+** Read or write a four-byte big-endian integer value.
+*/
+SQLITE_PRIVATE u32 sqlite3Get4byte(const u8 *p){
+ testcase( p[0]&0x80 );
+ return ((unsigned)p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
+}
+SQLITE_PRIVATE void sqlite3Put4byte(unsigned char *p, u32 v){
+ p[0] = (u8)(v>>24);
+ p[1] = (u8)(v>>16);
+ p[2] = (u8)(v>>8);
+ p[3] = (u8)v;
+}
+
+
+
+/*
+** Translate a single byte of Hex into an integer.
+** This routine only works if h really is a valid hexadecimal
+** character: 0..9a..fA..F
+*/
+SQLITE_PRIVATE u8 sqlite3HexToInt(int h){
+ assert( (h>='0' && h<='9') || (h>='a' && h<='f') || (h>='A' && h<='F') );
+#ifdef SQLITE_ASCII
+ h += 9*(1&(h>>6));
+#endif
+#ifdef SQLITE_EBCDIC
+ h += 9*(1&~(h>>4));
+#endif
+ return (u8)(h & 0xf);
+}
+
+#if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
+/*
+** Convert a BLOB literal of the form "x'hhhhhh'" into its binary
+** value. Return a pointer to its binary value. Space to hold the
+** binary value has been obtained from malloc and must be freed by
+** the calling routine.
+*/
+SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3 *db, const char *z, int n){
+ char *zBlob;
+ int i;
+
+ zBlob = (char *)sqlite3DbMallocRaw(db, n/2 + 1);
+ n--;
+ if( zBlob ){
+ for(i=0; imagic;
+ if( magic!=SQLITE_MAGIC_OPEN ){
+ if( sqlite3SafetyCheckSickOrOk(db) ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ logBadConnection("unopened");
+ }
+ return 0;
+ }else{
+ return 1;
+ }
+}
+SQLITE_PRIVATE int sqlite3SafetyCheckSickOrOk(sqlite3 *db){
+ u32 magic;
+ magic = db->magic;
+ if( magic!=SQLITE_MAGIC_SICK &&
+ magic!=SQLITE_MAGIC_OPEN &&
+ magic!=SQLITE_MAGIC_BUSY ){
+ testcase( sqlite3GlobalConfig.xLog!=0 );
+ logBadConnection("invalid");
+ return 0;
+ }else{
+ return 1;
+ }
+}
+
+/*
+** Attempt to add, substract, or multiply the 64-bit signed value iB against
+** the other 64-bit signed integer at *pA and store the result in *pA.
+** Return 0 on success. Or if the operation would have resulted in an
+** overflow, leave *pA unchanged and return 1.
+*/
+SQLITE_PRIVATE int sqlite3AddInt64(i64 *pA, i64 iB){
+ i64 iA = *pA;
+ testcase( iA==0 ); testcase( iA==1 );
+ testcase( iB==-1 ); testcase( iB==0 );
+ if( iB>=0 ){
+ testcase( iA>0 && LARGEST_INT64 - iA == iB );
+ testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 );
+ if( iA>0 && LARGEST_INT64 - iA < iB ) return 1;
+ }else{
+ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 );
+ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 );
+ if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1;
+ }
+ *pA += iB;
+ return 0;
+}
+SQLITE_PRIVATE int sqlite3SubInt64(i64 *pA, i64 iB){
+ testcase( iB==SMALLEST_INT64+1 );
+ if( iB==SMALLEST_INT64 ){
+ testcase( (*pA)==(-1) ); testcase( (*pA)==0 );
+ if( (*pA)>=0 ) return 1;
+ *pA -= iB;
+ return 0;
+ }else{
+ return sqlite3AddInt64(pA, -iB);
+ }
+}
+#define TWOPOWER32 (((i64)1)<<32)
+#define TWOPOWER31 (((i64)1)<<31)
+SQLITE_PRIVATE int sqlite3MulInt64(i64 *pA, i64 iB){
+ i64 iA = *pA;
+ i64 iA1, iA0, iB1, iB0, r;
+
+ iA1 = iA/TWOPOWER32;
+ iA0 = iA % TWOPOWER32;
+ iB1 = iB/TWOPOWER32;
+ iB0 = iB % TWOPOWER32;
+ if( iA1==0 ){
+ if( iB1==0 ){
+ *pA *= iB;
+ return 0;
+ }
+ r = iA0*iB1;
+ }else if( iB1==0 ){
+ r = iA1*iB0;
+ }else{
+ /* If both iA1 and iB1 are non-zero, overflow will result */
+ return 1;
+ }
+ testcase( r==(-TWOPOWER31)-1 );
+ testcase( r==(-TWOPOWER31) );
+ testcase( r==TWOPOWER31 );
+ testcase( r==TWOPOWER31-1 );
+ if( r<(-TWOPOWER31) || r>=TWOPOWER31 ) return 1;
+ r *= TWOPOWER32;
+ if( sqlite3AddInt64(&r, iA0*iB0) ) return 1;
+ *pA = r;
+ return 0;
+}
+
+/*
+** Compute the absolute value of a 32-bit signed integer, of possible. Or
+** if the integer has a value of -2147483648, return +2147483647
+*/
+SQLITE_PRIVATE int sqlite3AbsInt32(int x){
+ if( x>=0 ) return x;
+ if( x==(int)0x80000000 ) return 0x7fffffff;
+ return -x;
+}
+
+#ifdef SQLITE_ENABLE_8_3_NAMES
+/*
+** If SQLITE_ENABLE_8_3_NAMES is set at compile-time and if the database
+** filename in zBaseFilename is a URI with the "8_3_names=1" parameter and
+** if filename in z[] has a suffix (a.k.a. "extension") that is longer than
+** three characters, then shorten the suffix on z[] to be the last three
+** characters of the original suffix.
+**
+** If SQLITE_ENABLE_8_3_NAMES is set to 2 at compile-time, then always
+** do the suffix shortening regardless of URI parameter.
+**
+** Examples:
+**
+** test.db-journal => test.nal
+** test.db-wal => test.wal
+** test.db-shm => test.shm
+** test.db-mj7f3319fa => test.9fa
+*/
+SQLITE_PRIVATE void sqlite3FileSuffix3(const char *zBaseFilename, char *z){
+#if SQLITE_ENABLE_8_3_NAMES<2
+ if( sqlite3_uri_boolean(zBaseFilename, "8_3_names", 0) )
+#endif
+ {
+ int i, sz;
+ sz = sqlite3Strlen30(z);
+ for(i=sz-1; i>0 && z[i]!='/' && z[i]!='.'; i--){}
+ if( z[i]=='.' && ALWAYS(sz>i+4) ) memmove(&z[i+1], &z[sz-3], 4);
+ }
+}
+#endif
+
+/*
+** Find (an approximate) sum of two LogEst values. This computation is
+** not a simple "+" operator because LogEst is stored as a logarithmic
+** value.
+**
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst a, LogEst b){
+ static const unsigned char x[] = {
+ 10, 10, /* 0,1 */
+ 9, 9, /* 2,3 */
+ 8, 8, /* 4,5 */
+ 7, 7, 7, /* 6,7,8 */
+ 6, 6, 6, /* 9,10,11 */
+ 5, 5, 5, /* 12-14 */
+ 4, 4, 4, 4, /* 15-18 */
+ 3, 3, 3, 3, 3, 3, /* 19-24 */
+ 2, 2, 2, 2, 2, 2, 2, /* 25-31 */
+ };
+ if( a>=b ){
+ if( a>b+49 ) return a;
+ if( a>b+31 ) return a+1;
+ return a+x[a-b];
+ }else{
+ if( b>a+49 ) return b;
+ if( b>a+31 ) return b+1;
+ return b+x[b-a];
+ }
+}
+
+/*
+** Convert an integer into a LogEst. In other words, compute an
+** approximation for 10*log2(x).
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEst(u64 x){
+ static LogEst a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
+ LogEst y = 40;
+ if( x<8 ){
+ if( x<2 ) return 0;
+ while( x<8 ){ y -= 10; x <<= 1; }
+ }else{
+ while( x>255 ){ y += 40; x >>= 4; }
+ while( x>15 ){ y += 10; x >>= 1; }
+ }
+ return a[x&7] + y - 10;
+}
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/*
+** Convert a double into a LogEst
+** In other words, compute an approximation for 10*log2(x).
+*/
+SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double x){
+ u64 a;
+ LogEst e;
+ assert( sizeof(x)==8 && sizeof(a)==8 );
+ if( x<=1 ) return 0;
+ if( x<=2000000000 ) return sqlite3LogEst((u64)x);
+ memcpy(&a, &x, 8);
+ e = (a>>52) - 1022;
+ return e*10;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+/*
+** Convert a LogEst into an integer.
+*/
+SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst x){
+ u64 n;
+ if( x<10 ) return 1;
+ n = x%10;
+ x /= 10;
+ if( n>=5 ) n -= 2;
+ else if( n>=1 ) n -= 1;
+ if( x>=3 ){
+ return x>60 ? (u64)LARGEST_INT64 : (n+8)<<(x-3);
+ }
+ return (n+8)>>(3-x);
+}
+
+/************** End of util.c ************************************************/
+/************** Begin file hash.c ********************************************/
+/*
+** 2001 September 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the implementation of generic hash-tables
+** used in SQLite.
+*/
+/* #include */
+
+/* Turn bulk memory into a hash table object by initializing the
+** fields of the Hash structure.
+**
+** "pNew" is a pointer to the hash table that is to be initialized.
+*/
+SQLITE_PRIVATE void sqlite3HashInit(Hash *pNew){
+ assert( pNew!=0 );
+ pNew->first = 0;
+ pNew->count = 0;
+ pNew->htsize = 0;
+ pNew->ht = 0;
+}
+
+/* Remove all entries from a hash table. Reclaim all memory.
+** Call this routine to delete a hash table or to reset a hash table
+** to the empty state.
+*/
+SQLITE_PRIVATE void sqlite3HashClear(Hash *pH){
+ HashElem *elem; /* For looping over all elements of the table */
+
+ assert( pH!=0 );
+ elem = pH->first;
+ pH->first = 0;
+ sqlite3_free(pH->ht);
+ pH->ht = 0;
+ pH->htsize = 0;
+ while( elem ){
+ HashElem *next_elem = elem->next;
+ sqlite3_free(elem);
+ elem = next_elem;
+ }
+ pH->count = 0;
+}
+
+/*
+** The hashing function.
+*/
+static unsigned int strHash(const char *z, int nKey){
+ unsigned int h = 0;
+ assert( nKey>=0 );
+ while( nKey > 0 ){
+ h = (h<<3) ^ h ^ sqlite3UpperToLower[(unsigned char)*z++];
+ nKey--;
+ }
+ return h;
+}
+
+
+/* Link pNew element into the hash table pH. If pEntry!=0 then also
+** insert pNew into the pEntry hash bucket.
+*/
+static void insertElement(
+ Hash *pH, /* The complete hash table */
+ struct _ht *pEntry, /* The entry into which pNew is inserted */
+ HashElem *pNew /* The element to be inserted */
+){
+ HashElem *pHead; /* First element already in pEntry */
+ if( pEntry ){
+ pHead = pEntry->count ? pEntry->chain : 0;
+ pEntry->count++;
+ pEntry->chain = pNew;
+ }else{
+ pHead = 0;
+ }
+ if( pHead ){
+ pNew->next = pHead;
+ pNew->prev = pHead->prev;
+ if( pHead->prev ){ pHead->prev->next = pNew; }
+ else { pH->first = pNew; }
+ pHead->prev = pNew;
+ }else{
+ pNew->next = pH->first;
+ if( pH->first ){ pH->first->prev = pNew; }
+ pNew->prev = 0;
+ pH->first = pNew;
+ }
+}
+
+
+/* Resize the hash table so that it cantains "new_size" buckets.
+**
+** The hash table might fail to resize if sqlite3_malloc() fails or
+** if the new size is the same as the prior size.
+** Return TRUE if the resize occurs and false if not.
+*/
+static int rehash(Hash *pH, unsigned int new_size){
+ struct _ht *new_ht; /* The new hash table */
+ HashElem *elem, *next_elem; /* For looping over existing elements */
+
+#if SQLITE_MALLOC_SOFT_LIMIT>0
+ if( new_size*sizeof(struct _ht)>SQLITE_MALLOC_SOFT_LIMIT ){
+ new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
+ }
+ if( new_size==pH->htsize ) return 0;
+#endif
+
+ /* The inability to allocates space for a larger hash table is
+ ** a performance hit but it is not a fatal error. So mark the
+ ** allocation as a benign. Use sqlite3Malloc()/memset(0) instead of
+ ** sqlite3MallocZero() to make the allocation, as sqlite3MallocZero()
+ ** only zeroes the requested number of bytes whereas this module will
+ ** use the actual amount of space allocated for the hash table (which
+ ** may be larger than the requested amount).
+ */
+ sqlite3BeginBenignMalloc();
+ new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
+ sqlite3EndBenignMalloc();
+
+ if( new_ht==0 ) return 0;
+ sqlite3_free(pH->ht);
+ pH->ht = new_ht;
+ pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
+ memset(new_ht, 0, new_size*sizeof(struct _ht));
+ for(elem=pH->first, pH->first=0; elem; elem = next_elem){
+ unsigned int h = strHash(elem->pKey, elem->nKey) % new_size;
+ next_elem = elem->next;
+ insertElement(pH, &new_ht[h], elem);
+ }
+ return 1;
+}
+
+/* This function (for internal use only) locates an element in an
+** hash table that matches the given key. The hash for this key has
+** already been computed and is passed as the 4th parameter.
+*/
+static HashElem *findElementGivenHash(
+ const Hash *pH, /* The pH to be searched */
+ const char *pKey, /* The key we are searching for */
+ int nKey, /* Bytes in key (not counting zero terminator) */
+ unsigned int h /* The hash for this key. */
+){
+ HashElem *elem; /* Used to loop thru the element list */
+ int count; /* Number of elements left to test */
+
+ if( pH->ht ){
+ struct _ht *pEntry = &pH->ht[h];
+ elem = pEntry->chain;
+ count = pEntry->count;
+ }else{
+ elem = pH->first;
+ count = pH->count;
+ }
+ while( count-- && ALWAYS(elem) ){
+ if( elem->nKey==nKey && sqlite3StrNICmp(elem->pKey,pKey,nKey)==0 ){
+ return elem;
+ }
+ elem = elem->next;
+ }
+ return 0;
+}
+
+/* Remove a single entry from the hash table given a pointer to that
+** element and a hash on the element's key.
+*/
+static void removeElementGivenHash(
+ Hash *pH, /* The pH containing "elem" */
+ HashElem* elem, /* The element to be removed from the pH */
+ unsigned int h /* Hash value for the element */
+){
+ struct _ht *pEntry;
+ if( elem->prev ){
+ elem->prev->next = elem->next;
+ }else{
+ pH->first = elem->next;
+ }
+ if( elem->next ){
+ elem->next->prev = elem->prev;
+ }
+ if( pH->ht ){
+ pEntry = &pH->ht[h];
+ if( pEntry->chain==elem ){
+ pEntry->chain = elem->next;
+ }
+ pEntry->count--;
+ assert( pEntry->count>=0 );
+ }
+ sqlite3_free( elem );
+ pH->count--;
+ if( pH->count==0 ){
+ assert( pH->first==0 );
+ assert( pH->count==0 );
+ sqlite3HashClear(pH);
+ }
+}
+
+/* Attempt to locate an element of the hash table pH with a key
+** that matches pKey,nKey. Return the data for this element if it is
+** found, or NULL if there is no match.
+*/
+SQLITE_PRIVATE void *sqlite3HashFind(const Hash *pH, const char *pKey, int nKey){
+ HashElem *elem; /* The element that matches key */
+ unsigned int h; /* A hash on key */
+
+ assert( pH!=0 );
+ assert( pKey!=0 );
+ assert( nKey>=0 );
+ if( pH->ht ){
+ h = strHash(pKey, nKey) % pH->htsize;
+ }else{
+ h = 0;
+ }
+ elem = findElementGivenHash(pH, pKey, nKey, h);
+ return elem ? elem->data : 0;
+}
+
+/* Insert an element into the hash table pH. The key is pKey,nKey
+** and the data is "data".
+**
+** If no element exists with a matching key, then a new
+** element is created and NULL is returned.
+**
+** If another element already exists with the same key, then the
+** new data replaces the old data and the old data is returned.
+** The key is not copied in this instance. If a malloc fails, then
+** the new data is returned and the hash table is unchanged.
+**
+** If the "data" parameter to this function is NULL, then the
+** element corresponding to "key" is removed from the hash table.
+*/
+SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const char *pKey, int nKey, void *data){
+ unsigned int h; /* the hash of the key modulo hash table size */
+ HashElem *elem; /* Used to loop thru the element list */
+ HashElem *new_elem; /* New element added to the pH */
+
+ assert( pH!=0 );
+ assert( pKey!=0 );
+ assert( nKey>=0 );
+ if( pH->htsize ){
+ h = strHash(pKey, nKey) % pH->htsize;
+ }else{
+ h = 0;
+ }
+ elem = findElementGivenHash(pH,pKey,nKey,h);
+ if( elem ){
+ void *old_data = elem->data;
+ if( data==0 ){
+ removeElementGivenHash(pH,elem,h);
+ }else{
+ elem->data = data;
+ elem->pKey = pKey;
+ assert(nKey==elem->nKey);
+ }
+ return old_data;
+ }
+ if( data==0 ) return 0;
+ new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
+ if( new_elem==0 ) return data;
+ new_elem->pKey = pKey;
+ new_elem->nKey = nKey;
+ new_elem->data = data;
+ pH->count++;
+ if( pH->count>=10 && pH->count > 2*pH->htsize ){
+ if( rehash(pH, pH->count*2) ){
+ assert( pH->htsize>0 );
+ h = strHash(pKey, nKey) % pH->htsize;
+ }
+ }
+ if( pH->ht ){
+ insertElement(pH, &pH->ht[h], new_elem);
+ }else{
+ insertElement(pH, 0, new_elem);
+ }
+ return 0;
+}
+
+/************** End of hash.c ************************************************/
+/************** Begin file opcodes.c *****************************************/
+/* Automatically generated. Do not edit */
+/* See the mkopcodec.awk script for details. */
+#if !defined(SQLITE_OMIT_EXPLAIN) || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
+#if defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) || defined(SQLITE_DEBUG)
+# define OpHelp(X) "\0" X
+#else
+# define OpHelp(X)
+#endif
+SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
+ static const char *const azName[] = { "?",
+ /* 1 */ "Function" OpHelp("r[P3]=func(r[P2@P5])"),
+ /* 2 */ "Savepoint" OpHelp(""),
+ /* 3 */ "AutoCommit" OpHelp(""),
+ /* 4 */ "Transaction" OpHelp(""),
+ /* 5 */ "SorterNext" OpHelp(""),
+ /* 6 */ "PrevIfOpen" OpHelp(""),
+ /* 7 */ "NextIfOpen" OpHelp(""),
+ /* 8 */ "Prev" OpHelp(""),
+ /* 9 */ "Next" OpHelp(""),
+ /* 10 */ "AggStep" OpHelp("accum=r[P3] step(r[P2@P5])"),
+ /* 11 */ "Checkpoint" OpHelp(""),
+ /* 12 */ "JournalMode" OpHelp(""),
+ /* 13 */ "Vacuum" OpHelp(""),
+ /* 14 */ "VFilter" OpHelp("iplan=r[P3] zplan='P4'"),
+ /* 15 */ "VUpdate" OpHelp("data=r[P3@P2]"),
+ /* 16 */ "Goto" OpHelp(""),
+ /* 17 */ "Gosub" OpHelp(""),
+ /* 18 */ "Return" OpHelp(""),
+ /* 19 */ "Not" OpHelp("r[P2]= !r[P1]"),
+ /* 20 */ "InitCoroutine" OpHelp(""),
+ /* 21 */ "EndCoroutine" OpHelp(""),
+ /* 22 */ "Yield" OpHelp(""),
+ /* 23 */ "HaltIfNull" OpHelp("if r[P3]=null halt"),
+ /* 24 */ "Halt" OpHelp(""),
+ /* 25 */ "Integer" OpHelp("r[P2]=P1"),
+ /* 26 */ "Int64" OpHelp("r[P2]=P4"),
+ /* 27 */ "String" OpHelp("r[P2]='P4' (len=P1)"),
+ /* 28 */ "Null" OpHelp("r[P2..P3]=NULL"),
+ /* 29 */ "SoftNull" OpHelp("r[P1]=NULL"),
+ /* 30 */ "Blob" OpHelp("r[P2]=P4 (len=P1)"),
+ /* 31 */ "Variable" OpHelp("r[P2]=parameter(P1,P4)"),
+ /* 32 */ "Move" OpHelp("r[P2@P3]=r[P1@P3]"),
+ /* 33 */ "Copy" OpHelp("r[P2@P3+1]=r[P1@P3+1]"),
+ /* 34 */ "SCopy" OpHelp("r[P2]=r[P1]"),
+ /* 35 */ "ResultRow" OpHelp("output=r[P1@P2]"),
+ /* 36 */ "CollSeq" OpHelp(""),
+ /* 37 */ "AddImm" OpHelp("r[P1]=r[P1]+P2"),
+ /* 38 */ "MustBeInt" OpHelp(""),
+ /* 39 */ "RealAffinity" OpHelp(""),
+ /* 40 */ "Permutation" OpHelp(""),
+ /* 41 */ "Compare" OpHelp("r[P1@P3] <-> r[P2@P3]"),
+ /* 42 */ "Jump" OpHelp(""),
+ /* 43 */ "Once" OpHelp(""),
+ /* 44 */ "If" OpHelp(""),
+ /* 45 */ "IfNot" OpHelp(""),
+ /* 46 */ "Column" OpHelp("r[P3]=PX"),
+ /* 47 */ "Affinity" OpHelp("affinity(r[P1@P2])"),
+ /* 48 */ "MakeRecord" OpHelp("r[P3]=mkrec(r[P1@P2])"),
+ /* 49 */ "Count" OpHelp("r[P2]=count()"),
+ /* 50 */ "ReadCookie" OpHelp(""),
+ /* 51 */ "SetCookie" OpHelp(""),
+ /* 52 */ "OpenRead" OpHelp("root=P2 iDb=P3"),
+ /* 53 */ "OpenWrite" OpHelp("root=P2 iDb=P3"),
+ /* 54 */ "OpenAutoindex" OpHelp("nColumn=P2"),
+ /* 55 */ "OpenEphemeral" OpHelp("nColumn=P2"),
+ /* 56 */ "SorterOpen" OpHelp(""),
+ /* 57 */ "OpenPseudo" OpHelp("P3 columns in r[P2]"),
+ /* 58 */ "Close" OpHelp(""),
+ /* 59 */ "SeekLT" OpHelp(""),
+ /* 60 */ "SeekLE" OpHelp(""),
+ /* 61 */ "SeekGE" OpHelp(""),
+ /* 62 */ "SeekGT" OpHelp(""),
+ /* 63 */ "Seek" OpHelp("intkey=r[P2]"),
+ /* 64 */ "NoConflict" OpHelp("key=r[P3@P4]"),
+ /* 65 */ "NotFound" OpHelp("key=r[P3@P4]"),
+ /* 66 */ "Found" OpHelp("key=r[P3@P4]"),
+ /* 67 */ "NotExists" OpHelp("intkey=r[P3]"),
+ /* 68 */ "Sequence" OpHelp("r[P2]=cursor[P1].ctr++"),
+ /* 69 */ "NewRowid" OpHelp("r[P2]=rowid"),
+ /* 70 */ "Insert" OpHelp("intkey=r[P3] data=r[P2]"),
+ /* 71 */ "Or" OpHelp("r[P3]=(r[P1] || r[P2])"),
+ /* 72 */ "And" OpHelp("r[P3]=(r[P1] && r[P2])"),
+ /* 73 */ "InsertInt" OpHelp("intkey=P3 data=r[P2]"),
+ /* 74 */ "Delete" OpHelp(""),
+ /* 75 */ "ResetCount" OpHelp(""),
+ /* 76 */ "IsNull" OpHelp("if r[P1]==NULL goto P2"),
+ /* 77 */ "NotNull" OpHelp("if r[P1]!=NULL goto P2"),
+ /* 78 */ "Ne" OpHelp("if r[P1]!=r[P3] goto P2"),
+ /* 79 */ "Eq" OpHelp("if r[P1]==r[P3] goto P2"),
+ /* 80 */ "Gt" OpHelp("if r[P1]>r[P3] goto P2"),
+ /* 81 */ "Le" OpHelp("if r[P1]<=r[P3] goto P2"),
+ /* 82 */ "Lt" OpHelp("if r[P1]=r[P3] goto P2"),
+ /* 84 */ "SorterCompare" OpHelp("if key(P1)!=rtrim(r[P3],P4) goto P2"),
+ /* 85 */ "BitAnd" OpHelp("r[P3]=r[P1]&r[P2]"),
+ /* 86 */ "BitOr" OpHelp("r[P3]=r[P1]|r[P2]"),
+ /* 87 */ "ShiftLeft" OpHelp("r[P3]=r[P2]<>r[P1]"),
+ /* 89 */ "Add" OpHelp("r[P3]=r[P1]+r[P2]"),
+ /* 90 */ "Subtract" OpHelp("r[P3]=r[P2]-r[P1]"),
+ /* 91 */ "Multiply" OpHelp("r[P3]=r[P1]*r[P2]"),
+ /* 92 */ "Divide" OpHelp("r[P3]=r[P2]/r[P1]"),
+ /* 93 */ "Remainder" OpHelp("r[P3]=r[P2]%r[P1]"),
+ /* 94 */ "Concat" OpHelp("r[P3]=r[P2]+r[P1]"),
+ /* 95 */ "SorterData" OpHelp("r[P2]=data"),
+ /* 96 */ "BitNot" OpHelp("r[P1]= ~r[P1]"),
+ /* 97 */ "String8" OpHelp("r[P2]='P4'"),
+ /* 98 */ "RowKey" OpHelp("r[P2]=key"),
+ /* 99 */ "RowData" OpHelp("r[P2]=data"),
+ /* 100 */ "Rowid" OpHelp("r[P2]=rowid"),
+ /* 101 */ "NullRow" OpHelp(""),
+ /* 102 */ "Last" OpHelp(""),
+ /* 103 */ "SorterSort" OpHelp(""),
+ /* 104 */ "Sort" OpHelp(""),
+ /* 105 */ "Rewind" OpHelp(""),
+ /* 106 */ "SorterInsert" OpHelp(""),
+ /* 107 */ "IdxInsert" OpHelp("key=r[P2]"),
+ /* 108 */ "IdxDelete" OpHelp("key=r[P2@P3]"),
+ /* 109 */ "IdxRowid" OpHelp("r[P2]=rowid"),
+ /* 110 */ "IdxLE" OpHelp("key=r[P3@P4]"),
+ /* 111 */ "IdxGT" OpHelp("key=r[P3@P4]"),
+ /* 112 */ "IdxLT" OpHelp("key=r[P3@P4]"),
+ /* 113 */ "IdxGE" OpHelp("key=r[P3@P4]"),
+ /* 114 */ "Destroy" OpHelp(""),
+ /* 115 */ "Clear" OpHelp(""),
+ /* 116 */ "ResetSorter" OpHelp(""),
+ /* 117 */ "CreateIndex" OpHelp("r[P2]=root iDb=P1"),
+ /* 118 */ "CreateTable" OpHelp("r[P2]=root iDb=P1"),
+ /* 119 */ "ParseSchema" OpHelp(""),
+ /* 120 */ "LoadAnalysis" OpHelp(""),
+ /* 121 */ "DropTable" OpHelp(""),
+ /* 122 */ "DropIndex" OpHelp(""),
+ /* 123 */ "DropTrigger" OpHelp(""),
+ /* 124 */ "IntegrityCk" OpHelp(""),
+ /* 125 */ "RowSetAdd" OpHelp("rowset(P1)=r[P2]"),
+ /* 126 */ "RowSetRead" OpHelp("r[P3]=rowset(P1)"),
+ /* 127 */ "RowSetTest" OpHelp("if r[P3] in rowset(P1) goto P2"),
+ /* 128 */ "Program" OpHelp(""),
+ /* 129 */ "Param" OpHelp(""),
+ /* 130 */ "FkCounter" OpHelp("fkctr[P1]+=P2"),
+ /* 131 */ "FkIfZero" OpHelp("if fkctr[P1]==0 goto P2"),
+ /* 132 */ "MemMax" OpHelp("r[P1]=max(r[P1],r[P2])"),
+ /* 133 */ "Real" OpHelp("r[P2]=P4"),
+ /* 134 */ "IfPos" OpHelp("if r[P1]>0 goto P2"),
+ /* 135 */ "IfNeg" OpHelp("if r[P1]<0 goto P2"),
+ /* 136 */ "IfZero" OpHelp("r[P1]+=P3, if r[P1]==0 goto P2"),
+ /* 137 */ "AggFinal" OpHelp("accum=r[P1] N=P2"),
+ /* 138 */ "IncrVacuum" OpHelp(""),
+ /* 139 */ "Expire" OpHelp(""),
+ /* 140 */ "TableLock" OpHelp("iDb=P1 root=P2 write=P3"),
+ /* 141 */ "VBegin" OpHelp(""),
+ /* 142 */ "VCreate" OpHelp(""),
+ /* 143 */ "ToText" OpHelp(""),
+ /* 144 */ "ToBlob" OpHelp(""),
+ /* 145 */ "ToNumeric" OpHelp(""),
+ /* 146 */ "ToInt" OpHelp(""),
+ /* 147 */ "ToReal" OpHelp(""),
+ /* 148 */ "VDestroy" OpHelp(""),
+ /* 149 */ "VOpen" OpHelp(""),
+ /* 150 */ "VColumn" OpHelp("r[P3]=vcolumn(P2)"),
+ /* 151 */ "VNext" OpHelp(""),
+ /* 152 */ "VRename" OpHelp(""),
+ /* 153 */ "Pagecount" OpHelp(""),
+ /* 154 */ "MaxPgcnt" OpHelp(""),
+ /* 155 */ "Init" OpHelp("Start at P2"),
+ /* 156 */ "Noop" OpHelp(""),
+ /* 157 */ "Explain" OpHelp(""),
+ };
+ return azName[i];
+}
+#endif
+
+/************** End of opcodes.c *********************************************/
+/************** Begin file os_unix.c *****************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains the VFS implementation for unix-like operating systems
+** include Linux, MacOSX, *BSD, QNX, VxWorks, AIX, HPUX, and others.
+**
+** There are actually several different VFS implementations in this file.
+** The differences are in the way that file locking is done. The default
+** implementation uses Posix Advisory Locks. Alternative implementations
+** use flock(), dot-files, various proprietary locking schemas, or simply
+** skip locking all together.
+**
+** This source file is organized into divisions where the logic for various
+** subfunctions is contained within the appropriate division. PLEASE
+** KEEP THE STRUCTURE OF THIS FILE INTACT. New code should be placed
+** in the correct division and should be clearly labeled.
+**
+** The layout of divisions is as follows:
+**
+** * General-purpose declarations and utility functions.
+** * Unique file ID logic used by VxWorks.
+** * Various locking primitive implementations (all except proxy locking):
+** + for Posix Advisory Locks
+** + for no-op locks
+** + for dot-file locks
+** + for flock() locking
+** + for named semaphore locks (VxWorks only)
+** + for AFP filesystem locks (MacOSX only)
+** * sqlite3_file methods not associated with locking.
+** * Definitions of sqlite3_io_methods objects for all locking
+** methods plus "finder" functions for each locking method.
+** * sqlite3_vfs method implementations.
+** * Locking primitives for the proxy uber-locking-method. (MacOSX only)
+** * Definitions of sqlite3_vfs objects for all locking methods
+** plus implementations of sqlite3_os_init() and sqlite3_os_end().
+*/
+#if SQLITE_OS_UNIX /* This file is used on unix only */
+
+/*
+** There are various methods for file locking used for concurrency
+** control:
+**
+** 1. POSIX locking (the default),
+** 2. No locking,
+** 3. Dot-file locking,
+** 4. flock() locking,
+** 5. AFP locking (OSX only),
+** 6. Named POSIX semaphores (VXWorks only),
+** 7. proxy locking. (OSX only)
+**
+** Styles 4, 5, and 7 are only available of SQLITE_ENABLE_LOCKING_STYLE
+** is defined to 1. The SQLITE_ENABLE_LOCKING_STYLE also enables automatic
+** selection of the appropriate locking style based on the filesystem
+** where the database is located.
+*/
+#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
+# if defined(__APPLE__)
+# define SQLITE_ENABLE_LOCKING_STYLE 1
+# else
+# define SQLITE_ENABLE_LOCKING_STYLE 0
+# endif
+#endif
+
+/*
+** Define the OS_VXWORKS pre-processor macro to 1 if building on
+** vxworks, or 0 otherwise.
+*/
+#ifndef OS_VXWORKS
+# if defined(__RTP__) || defined(_WRS_KERNEL)
+# define OS_VXWORKS 1
+# else
+# define OS_VXWORKS 0
+# endif
+#endif
+
+/*
+** standard include files.
+*/
+#include
+#include
+#include
+#include
+/* #include */
+#include
+#include
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+#include
+#endif
+
+
+#if SQLITE_ENABLE_LOCKING_STYLE
+# include
+# if OS_VXWORKS
+# include
+# include
+# else
+# include
+# include
+# endif
+#endif /* SQLITE_ENABLE_LOCKING_STYLE */
+
+#if defined(__APPLE__) || (SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS)
+# include
+#endif
+
+#ifdef HAVE_UTIME
+# include
+#endif
+
+/*
+** Allowed values of unixFile.fsFlags
+*/
+#define SQLITE_FSFLAGS_IS_MSDOS 0x1
+
+/*
+** If we are to be thread-safe, include the pthreads header and define
+** the SQLITE_UNIX_THREADS macro.
+*/
+#if SQLITE_THREADSAFE
+/* # include */
+# define SQLITE_UNIX_THREADS 1
+#endif
+
+/*
+** Default permissions when creating a new file
+*/
+#ifndef SQLITE_DEFAULT_FILE_PERMISSIONS
+# define SQLITE_DEFAULT_FILE_PERMISSIONS 0644
+#endif
+
+/*
+** Default permissions when creating auto proxy dir
+*/
+#ifndef SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
+# define SQLITE_DEFAULT_PROXYDIR_PERMISSIONS 0755
+#endif
+
+/*
+** Maximum supported path-length.
+*/
+#define MAX_PATHNAME 512
+
+/*
+** Only set the lastErrno if the error code is a real error and not
+** a normal expected return code of SQLITE_BUSY or SQLITE_OK
+*/
+#define IS_LOCK_ERROR(x) ((x != SQLITE_OK) && (x != SQLITE_BUSY))
+
+/* Forward references */
+typedef struct unixShm unixShm; /* Connection shared memory */
+typedef struct unixShmNode unixShmNode; /* Shared memory instance */
+typedef struct unixInodeInfo unixInodeInfo; /* An i-node */
+typedef struct UnixUnusedFd UnixUnusedFd; /* An unused file descriptor */
+
+/*
+** Sometimes, after a file handle is closed by SQLite, the file descriptor
+** cannot be closed immediately. In these cases, instances of the following
+** structure are used to store the file descriptor while waiting for an
+** opportunity to either close or reuse it.
+*/
+struct UnixUnusedFd {
+ int fd; /* File descriptor to close */
+ int flags; /* Flags this file descriptor was opened with */
+ UnixUnusedFd *pNext; /* Next unused file descriptor on same file */
+};
+
+/*
+** The unixFile structure is subclass of sqlite3_file specific to the unix
+** VFS implementations.
+*/
+typedef struct unixFile unixFile;
+struct unixFile {
+ sqlite3_io_methods const *pMethod; /* Always the first entry */
+ sqlite3_vfs *pVfs; /* The VFS that created this unixFile */
+ unixInodeInfo *pInode; /* Info about locks on this inode */
+ int h; /* The file descriptor */
+ unsigned char eFileLock; /* The type of lock held on this fd */
+ unsigned short int ctrlFlags; /* Behavioral bits. UNIXFILE_* flags */
+ int lastErrno; /* The unix errno from last I/O error */
+ void *lockingContext; /* Locking style specific state */
+ UnixUnusedFd *pUnused; /* Pre-allocated UnixUnusedFd */
+ const char *zPath; /* Name of the file */
+ unixShm *pShm; /* Shared memory segment information */
+ int szChunk; /* Configured by FCNTL_CHUNK_SIZE */
+#if SQLITE_MAX_MMAP_SIZE>0
+ int nFetchOut; /* Number of outstanding xFetch refs */
+ sqlite3_int64 mmapSize; /* Usable size of mapping at pMapRegion */
+ sqlite3_int64 mmapSizeActual; /* Actual size of mapping at pMapRegion */
+ sqlite3_int64 mmapSizeMax; /* Configured FCNTL_MMAP_SIZE value */
+ void *pMapRegion; /* Memory mapped region */
+#endif
+#ifdef __QNXNTO__
+ int sectorSize; /* Device sector size */
+ int deviceCharacteristics; /* Precomputed device characteristics */
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE
+ int openFlags; /* The flags specified at open() */
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE || defined(__APPLE__)
+ unsigned fsFlags; /* cached details from statfs() */
+#endif
+#if OS_VXWORKS
+ struct vxworksFileId *pId; /* Unique file ID */
+#endif
+#ifdef SQLITE_DEBUG
+ /* The next group of variables are used to track whether or not the
+ ** transaction counter in bytes 24-27 of database files are updated
+ ** whenever any part of the database changes. An assertion fault will
+ ** occur if a file is updated without also updating the transaction
+ ** counter. This test is made to avoid new problems similar to the
+ ** one described by ticket #3584.
+ */
+ unsigned char transCntrChng; /* True if the transaction counter changed */
+ unsigned char dbUpdate; /* True if any part of database file changed */
+ unsigned char inNormalWrite; /* True if in a normal write operation */
+
+#endif
+
+#ifdef SQLITE_TEST
+ /* In test mode, increase the size of this structure a bit so that
+ ** it is larger than the struct CrashFile defined in test6.c.
+ */
+ char aPadding[32];
+#endif
+};
+
+/* This variable holds the process id (pid) from when the xRandomness()
+** method was called. If xOpen() is called from a different process id,
+** indicating that a fork() has occurred, the PRNG will be reset.
+*/
+static int randomnessPid = 0;
+
+/*
+** Allowed values for the unixFile.ctrlFlags bitmask:
+*/
+#define UNIXFILE_EXCL 0x01 /* Connections from one process only */
+#define UNIXFILE_RDONLY 0x02 /* Connection is read only */
+#define UNIXFILE_PERSIST_WAL 0x04 /* Persistent WAL mode */
+#ifndef SQLITE_DISABLE_DIRSYNC
+# define UNIXFILE_DIRSYNC 0x08 /* Directory sync needed */
+#else
+# define UNIXFILE_DIRSYNC 0x00
+#endif
+#define UNIXFILE_PSOW 0x10 /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
+#define UNIXFILE_DELETE 0x20 /* Delete on close */
+#define UNIXFILE_URI 0x40 /* Filename might have query parameters */
+#define UNIXFILE_NOLOCK 0x80 /* Do no file locking */
+#define UNIXFILE_WARNED 0x0100 /* verifyDbFile() warnings have been issued */
+
+/*
+** Include code that is common to all os_*.c files
+*/
+/************** Include os_common.h in the middle of os_unix.c ***************/
+/************** Begin file os_common.h ***************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains macros and a little bit of code that is common to
+** all of the platform-specific files (os_*.c) and is #included into those
+** files.
+**
+** This file should be #included by the os_*.c files only. It is not a
+** general purpose header file.
+*/
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
+
+/*
+** At least two bugs have slipped in because we changed the MEMORY_DEBUG
+** macro to SQLITE_DEBUG and some older makefiles have not yet made the
+** switch. The following code should catch this problem at compile-time.
+*/
+#ifdef MEMORY_DEBUG
+# error "The MEMORY_DEBUG macro is obsolete. Use SQLITE_DEBUG instead."
+#endif
+
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+# ifndef SQLITE_DEBUG_OS_TRACE
+# define SQLITE_DEBUG_OS_TRACE 0
+# endif
+ int sqlite3OSTrace = SQLITE_DEBUG_OS_TRACE;
+# define OSTRACE(X) if( sqlite3OSTrace ) sqlite3DebugPrintf X
+#else
+# define OSTRACE(X)
+#endif
+
+/*
+** Macros for performance tracing. Normally turned off. Only works
+** on i486 hardware.
+*/
+#ifdef SQLITE_PERFORMANCE_TRACE
+
+/*
+** hwtime.h contains inline assembler code for implementing
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
+/*
+** 2008 May 27
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+*/
+#ifndef _HWTIME_H_
+#define _HWTIME_H_
+
+/*
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value. This can be used for high-res
+** profiling.
+*/
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+ (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+ #if defined(__GNUC__)
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned int lo, hi;
+ __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+ return (sqlite_uint64)hi << 32 | lo;
+ }
+
+ #elif defined(_MSC_VER)
+
+ __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+ __asm {
+ rdtsc
+ ret ; return value at EDX:EAX
+ }
+ }
+
+ #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long val;
+ __asm__ __volatile__ ("rdtsc" : "=A" (val));
+ return val;
+ }
+
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long long retval;
+ unsigned long junk;
+ __asm__ __volatile__ ("\n\
+ 1: mftbu %1\n\
+ mftb %L0\n\
+ mftbu %0\n\
+ cmpw %0,%1\n\
+ bne 1b"
+ : "=r" (retval), "=r" (junk));
+ return retval;
+ }
+
+#else
+
+ #error Need implementation of sqlite3Hwtime() for your platform.
+
+ /*
+ ** To compile without implementing sqlite3Hwtime() for your platform,
+ ** you can remove the above #error and use the following
+ ** stub function. You will lose timing support for many
+ ** of the debugging and testing utilities, but it should at
+ ** least compile and run.
+ */
+SQLITE_PRIVATE sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(_HWTIME_H_) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START g_start=sqlite3Hwtime()
+#define TIMER_END g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED g_elapsed
+#else
+#define TIMER_START
+#define TIMER_END
+#define TIMER_ELAPSED ((sqlite_uint64)0)
+#endif
+
+/*
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error. This
+** is used for testing the I/O recovery logic.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_io_error_hit = 0; /* Total number of I/O Errors */
+SQLITE_API int sqlite3_io_error_hardhit = 0; /* Number of non-benign errors */
+SQLITE_API int sqlite3_io_error_pending = 0; /* Count down to first I/O error */
+SQLITE_API int sqlite3_io_error_persist = 0; /* True if I/O errors persist */
+SQLITE_API int sqlite3_io_error_benign = 0; /* True if errors are benign */
+SQLITE_API int sqlite3_diskfull_pending = 0;
+SQLITE_API int sqlite3_diskfull = 0;
+#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
+#define SimulateIOError(CODE) \
+ if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
+ || sqlite3_io_error_pending-- == 1 ) \
+ { local_ioerr(); CODE; }
+static void local_ioerr(){
+ IOTRACE(("IOERR\n"));
+ sqlite3_io_error_hit++;
+ if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
+}
+#define SimulateDiskfullError(CODE) \
+ if( sqlite3_diskfull_pending ){ \
+ if( sqlite3_diskfull_pending == 1 ){ \
+ local_ioerr(); \
+ sqlite3_diskfull = 1; \
+ sqlite3_io_error_hit = 1; \
+ CODE; \
+ }else{ \
+ sqlite3_diskfull_pending--; \
+ } \
+ }
+#else
+#define SimulateIOErrorBenign(X)
+#define SimulateIOError(A)
+#define SimulateDiskfullError(A)
+#endif
+
+/*
+** When testing, keep a count of the number of open files.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_open_file_count = 0;
+#define OpenCounter(X) sqlite3_open_file_count+=(X)
+#else
+#define OpenCounter(X)
+#endif
+
+#endif /* !defined(_OS_COMMON_H_) */
+
+/************** End of os_common.h *******************************************/
+/************** Continuing where we left off in os_unix.c ********************/
+
+/*
+** Define various macros that are missing from some systems.
+*/
+#ifndef O_LARGEFILE
+# define O_LARGEFILE 0
+#endif
+#ifdef SQLITE_DISABLE_LFS
+# undef O_LARGEFILE
+# define O_LARGEFILE 0
+#endif
+#ifndef O_NOFOLLOW
+# define O_NOFOLLOW 0
+#endif
+#ifndef O_BINARY
+# define O_BINARY 0
+#endif
+
+/*
+** The threadid macro resolves to the thread-id or to 0. Used for
+** testing and debugging only.
+*/
+#if SQLITE_THREADSAFE
+#define threadid pthread_self()
+#else
+#define threadid 0
+#endif
+
+/*
+** HAVE_MREMAP defaults to true on Linux and false everywhere else.
+*/
+#if !defined(HAVE_MREMAP)
+# if defined(__linux__) && defined(_GNU_SOURCE)
+# define HAVE_MREMAP 1
+# else
+# define HAVE_MREMAP 0
+# endif
+#endif
+
+/*
+** Different Unix systems declare open() in different ways. Same use
+** open(const char*,int,mode_t). Others use open(const char*,int,...).
+** The difference is important when using a pointer to the function.
+**
+** The safest way to deal with the problem is to always use this wrapper
+** which always has the same well-defined interface.
+*/
+static int posixOpen(const char *zFile, int flags, int mode){
+ return open(zFile, flags, mode);
+}
+
+/*
+** On some systems, calls to fchown() will trigger a message in a security
+** log if they come from non-root processes. So avoid calling fchown() if
+** we are not running as root.
+*/
+static int posixFchown(int fd, uid_t uid, gid_t gid){
+ return geteuid() ? 0 : fchown(fd,uid,gid);
+}
+
+/* Forward reference */
+static int openDirectory(const char*, int*);
+static int unixGetpagesize(void);
+
+/*
+** Many system calls are accessed through pointer-to-functions so that
+** they may be overridden at runtime to facilitate fault injection during
+** testing and sandboxing. The following array holds the names and pointers
+** to all overrideable system calls.
+*/
+static struct unix_syscall {
+ const char *zName; /* Name of the system call */
+ sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
+ sqlite3_syscall_ptr pDefault; /* Default value */
+} aSyscall[] = {
+ { "open", (sqlite3_syscall_ptr)posixOpen, 0 },
+#define osOpen ((int(*)(const char*,int,int))aSyscall[0].pCurrent)
+
+ { "close", (sqlite3_syscall_ptr)close, 0 },
+#define osClose ((int(*)(int))aSyscall[1].pCurrent)
+
+ { "access", (sqlite3_syscall_ptr)access, 0 },
+#define osAccess ((int(*)(const char*,int))aSyscall[2].pCurrent)
+
+ { "getcwd", (sqlite3_syscall_ptr)getcwd, 0 },
+#define osGetcwd ((char*(*)(char*,size_t))aSyscall[3].pCurrent)
+
+ { "stat", (sqlite3_syscall_ptr)stat, 0 },
+#define osStat ((int(*)(const char*,struct stat*))aSyscall[4].pCurrent)
+
+/*
+** The DJGPP compiler environment looks mostly like Unix, but it
+** lacks the fcntl() system call. So redefine fcntl() to be something
+** that always succeeds. This means that locking does not occur under
+** DJGPP. But it is DOS - what did you expect?
+*/
+#ifdef __DJGPP__
+ { "fstat", 0, 0 },
+#define osFstat(a,b,c) 0
+#else
+ { "fstat", (sqlite3_syscall_ptr)fstat, 0 },
+#define osFstat ((int(*)(int,struct stat*))aSyscall[5].pCurrent)
+#endif
+
+ { "ftruncate", (sqlite3_syscall_ptr)ftruncate, 0 },
+#define osFtruncate ((int(*)(int,off_t))aSyscall[6].pCurrent)
+
+ { "fcntl", (sqlite3_syscall_ptr)fcntl, 0 },
+#define osFcntl ((int(*)(int,int,...))aSyscall[7].pCurrent)
+
+ { "read", (sqlite3_syscall_ptr)read, 0 },
+#define osRead ((ssize_t(*)(int,void*,size_t))aSyscall[8].pCurrent)
+
+#if defined(USE_PREAD) || SQLITE_ENABLE_LOCKING_STYLE
+ { "pread", (sqlite3_syscall_ptr)pread, 0 },
+#else
+ { "pread", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPread ((ssize_t(*)(int,void*,size_t,off_t))aSyscall[9].pCurrent)
+
+#if defined(USE_PREAD64)
+ { "pread64", (sqlite3_syscall_ptr)pread64, 0 },
+#else
+ { "pread64", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPread64 ((ssize_t(*)(int,void*,size_t,off_t))aSyscall[10].pCurrent)
+
+ { "write", (sqlite3_syscall_ptr)write, 0 },
+#define osWrite ((ssize_t(*)(int,const void*,size_t))aSyscall[11].pCurrent)
+
+#if defined(USE_PREAD) || SQLITE_ENABLE_LOCKING_STYLE
+ { "pwrite", (sqlite3_syscall_ptr)pwrite, 0 },
+#else
+ { "pwrite", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPwrite ((ssize_t(*)(int,const void*,size_t,off_t))\
+ aSyscall[12].pCurrent)
+
+#if defined(USE_PREAD64)
+ { "pwrite64", (sqlite3_syscall_ptr)pwrite64, 0 },
+#else
+ { "pwrite64", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osPwrite64 ((ssize_t(*)(int,const void*,size_t,off_t))\
+ aSyscall[13].pCurrent)
+
+ { "fchmod", (sqlite3_syscall_ptr)fchmod, 0 },
+#define osFchmod ((int(*)(int,mode_t))aSyscall[14].pCurrent)
+
+#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
+ { "fallocate", (sqlite3_syscall_ptr)posix_fallocate, 0 },
+#else
+ { "fallocate", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osFallocate ((int(*)(int,off_t,off_t))aSyscall[15].pCurrent)
+
+ { "unlink", (sqlite3_syscall_ptr)unlink, 0 },
+#define osUnlink ((int(*)(const char*))aSyscall[16].pCurrent)
+
+ { "openDirectory", (sqlite3_syscall_ptr)openDirectory, 0 },
+#define osOpenDirectory ((int(*)(const char*,int*))aSyscall[17].pCurrent)
+
+ { "mkdir", (sqlite3_syscall_ptr)mkdir, 0 },
+#define osMkdir ((int(*)(const char*,mode_t))aSyscall[18].pCurrent)
+
+ { "rmdir", (sqlite3_syscall_ptr)rmdir, 0 },
+#define osRmdir ((int(*)(const char*))aSyscall[19].pCurrent)
+
+ { "fchown", (sqlite3_syscall_ptr)posixFchown, 0 },
+#define osFchown ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)
+
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
+ { "mmap", (sqlite3_syscall_ptr)mmap, 0 },
+#define osMmap ((void*(*)(void*,size_t,int,int,int,off_t))aSyscall[21].pCurrent)
+
+ { "munmap", (sqlite3_syscall_ptr)munmap, 0 },
+#define osMunmap ((void*(*)(void*,size_t))aSyscall[22].pCurrent)
+
+#if HAVE_MREMAP
+ { "mremap", (sqlite3_syscall_ptr)mremap, 0 },
+#else
+ { "mremap", (sqlite3_syscall_ptr)0, 0 },
+#endif
+#define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[23].pCurrent)
+#endif
+
+ { "getpagesize", (sqlite3_syscall_ptr)unixGetpagesize, 0 },
+#define osGetpagesize ((int(*)(void))aSyscall[24].pCurrent)
+
+}; /* End of the overrideable system calls */
+
+/*
+** This is the xSetSystemCall() method of sqlite3_vfs for all of the
+** "unix" VFSes. Return SQLITE_OK opon successfully updating the
+** system call pointer, or SQLITE_NOTFOUND if there is no configurable
+** system call named zName.
+*/
+static int unixSetSystemCall(
+ sqlite3_vfs *pNotUsed, /* The VFS pointer. Not used */
+ const char *zName, /* Name of system call to override */
+ sqlite3_syscall_ptr pNewFunc /* Pointer to new system call value */
+){
+ unsigned int i;
+ int rc = SQLITE_NOTFOUND;
+
+ UNUSED_PARAMETER(pNotUsed);
+ if( zName==0 ){
+ /* If no zName is given, restore all system calls to their default
+ ** settings and return NULL
+ */
+ rc = SQLITE_OK;
+ for(i=0; i=SQLITE_MINIMUM_FILE_DESCRIPTOR ) break;
+ osClose(fd);
+ sqlite3_log(SQLITE_WARNING,
+ "attempt to open \"%s\" as file descriptor %d", z, fd);
+ fd = -1;
+ if( osOpen("/dev/null", f, m)<0 ) break;
+ }
+ if( fd>=0 ){
+ if( m!=0 ){
+ struct stat statbuf;
+ if( osFstat(fd, &statbuf)==0
+ && statbuf.st_size==0
+ && (statbuf.st_mode&0777)!=m
+ ){
+ osFchmod(fd, m);
+ }
+ }
+#if defined(FD_CLOEXEC) && (!defined(O_CLOEXEC) || O_CLOEXEC==0)
+ osFcntl(fd, F_SETFD, osFcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
+#endif
+ }
+ return fd;
+}
+
+/*
+** Helper functions to obtain and relinquish the global mutex. The
+** global mutex is used to protect the unixInodeInfo and
+** vxworksFileId objects used by this file, all of which may be
+** shared by multiple threads.
+**
+** Function unixMutexHeld() is used to assert() that the global mutex
+** is held when required. This function is only used as part of assert()
+** statements. e.g.
+**
+** unixEnterMutex()
+** assert( unixMutexHeld() );
+** unixEnterLeave()
+*/
+static void unixEnterMutex(void){
+ sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+static void unixLeaveMutex(void){
+ sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+#ifdef SQLITE_DEBUG
+static int unixMutexHeld(void) {
+ return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+#endif
+
+
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+/*
+** Helper function for printing out trace information from debugging
+** binaries. This returns the string represetation of the supplied
+** integer lock-type.
+*/
+static const char *azFileLock(int eFileLock){
+ switch( eFileLock ){
+ case NO_LOCK: return "NONE";
+ case SHARED_LOCK: return "SHARED";
+ case RESERVED_LOCK: return "RESERVED";
+ case PENDING_LOCK: return "PENDING";
+ case EXCLUSIVE_LOCK: return "EXCLUSIVE";
+ }
+ return "ERROR";
+}
+#endif
+
+#ifdef SQLITE_LOCK_TRACE
+/*
+** Print out information about all locking operations.
+**
+** This routine is used for troubleshooting locks on multithreaded
+** platforms. Enable by compiling with the -DSQLITE_LOCK_TRACE
+** command-line option on the compiler. This code is normally
+** turned off.
+*/
+static int lockTrace(int fd, int op, struct flock *p){
+ char *zOpName, *zType;
+ int s;
+ int savedErrno;
+ if( op==F_GETLK ){
+ zOpName = "GETLK";
+ }else if( op==F_SETLK ){
+ zOpName = "SETLK";
+ }else{
+ s = osFcntl(fd, op, p);
+ sqlite3DebugPrintf("fcntl unknown %d %d %d\n", fd, op, s);
+ return s;
+ }
+ if( p->l_type==F_RDLCK ){
+ zType = "RDLCK";
+ }else if( p->l_type==F_WRLCK ){
+ zType = "WRLCK";
+ }else if( p->l_type==F_UNLCK ){
+ zType = "UNLCK";
+ }else{
+ assert( 0 );
+ }
+ assert( p->l_whence==SEEK_SET );
+ s = osFcntl(fd, op, p);
+ savedErrno = errno;
+ sqlite3DebugPrintf("fcntl %d %d %s %s %d %d %d %d\n",
+ threadid, fd, zOpName, zType, (int)p->l_start, (int)p->l_len,
+ (int)p->l_pid, s);
+ if( s==(-1) && op==F_SETLK && (p->l_type==F_RDLCK || p->l_type==F_WRLCK) ){
+ struct flock l2;
+ l2 = *p;
+ osFcntl(fd, F_GETLK, &l2);
+ if( l2.l_type==F_RDLCK ){
+ zType = "RDLCK";
+ }else if( l2.l_type==F_WRLCK ){
+ zType = "WRLCK";
+ }else if( l2.l_type==F_UNLCK ){
+ zType = "UNLCK";
+ }else{
+ assert( 0 );
+ }
+ sqlite3DebugPrintf("fcntl-failure-reason: %s %d %d %d\n",
+ zType, (int)l2.l_start, (int)l2.l_len, (int)l2.l_pid);
+ }
+ errno = savedErrno;
+ return s;
+}
+#undef osFcntl
+#define osFcntl lockTrace
+#endif /* SQLITE_LOCK_TRACE */
+
+/*
+** Retry ftruncate() calls that fail due to EINTR
+*/
+static int robust_ftruncate(int h, sqlite3_int64 sz){
+ int rc;
+ do{ rc = osFtruncate(h,sz); }while( rc<0 && errno==EINTR );
+ return rc;
+}
+
+/*
+** This routine translates a standard POSIX errno code into something
+** useful to the clients of the sqlite3 functions. Specifically, it is
+** intended to translate a variety of "try again" errors into SQLITE_BUSY
+** and a variety of "please close the file descriptor NOW" errors into
+** SQLITE_IOERR
+**
+** Errors during initialization of locks, or file system support for locks,
+** should handle ENOLCK, ENOTSUP, EOPNOTSUPP separately.
+*/
+static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
+ switch (posixError) {
+#if 0
+ /* At one point this code was not commented out. In theory, this branch
+ ** should never be hit, as this function should only be called after
+ ** a locking-related function (i.e. fcntl()) has returned non-zero with
+ ** the value of errno as the first argument. Since a system call has failed,
+ ** errno should be non-zero.
+ **
+ ** Despite this, if errno really is zero, we still don't want to return
+ ** SQLITE_OK. The system call failed, and *some* SQLite error should be
+ ** propagated back to the caller. Commenting this branch out means errno==0
+ ** will be handled by the "default:" case below.
+ */
+ case 0:
+ return SQLITE_OK;
+#endif
+
+ case EAGAIN:
+ case ETIMEDOUT:
+ case EBUSY:
+ case EINTR:
+ case ENOLCK:
+ /* random NFS retry error, unless during file system support
+ * introspection, in which it actually means what it says */
+ return SQLITE_BUSY;
+
+ case EACCES:
+ /* EACCES is like EAGAIN during locking operations, but not any other time*/
+ if( (sqliteIOErr == SQLITE_IOERR_LOCK) ||
+ (sqliteIOErr == SQLITE_IOERR_UNLOCK) ||
+ (sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
+ (sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
+ return SQLITE_BUSY;
+ }
+ /* else fall through */
+ case EPERM:
+ return SQLITE_PERM;
+
+ /* EDEADLK is only possible if a call to fcntl(F_SETLKW) is made. And
+ ** this module never makes such a call. And the code in SQLite itself
+ ** asserts that SQLITE_IOERR_BLOCKED is never returned. For these reasons
+ ** this case is also commented out. If the system does set errno to EDEADLK,
+ ** the default SQLITE_IOERR_XXX code will be returned. */
+#if 0
+ case EDEADLK:
+ return SQLITE_IOERR_BLOCKED;
+#endif
+
+#if EOPNOTSUPP!=ENOTSUP
+ case EOPNOTSUPP:
+ /* something went terribly awry, unless during file system support
+ * introspection, in which it actually means what it says */
+#endif
+#ifdef ENOTSUP
+ case ENOTSUP:
+ /* invalid fd, unless during file system support introspection, in which
+ * it actually means what it says */
+#endif
+ case EIO:
+ case EBADF:
+ case EINVAL:
+ case ENOTCONN:
+ case ENODEV:
+ case ENXIO:
+ case ENOENT:
+#ifdef ESTALE /* ESTALE is not defined on Interix systems */
+ case ESTALE:
+#endif
+ case ENOSYS:
+ /* these should force the client to close the file and reconnect */
+
+ default:
+ return sqliteIOErr;
+ }
+}
+
+
+/******************************************************************************
+****************** Begin Unique File ID Utility Used By VxWorks ***************
+**
+** On most versions of unix, we can get a unique ID for a file by concatenating
+** the device number and the inode number. But this does not work on VxWorks.
+** On VxWorks, a unique file id must be based on the canonical filename.
+**
+** A pointer to an instance of the following structure can be used as a
+** unique file ID in VxWorks. Each instance of this structure contains
+** a copy of the canonical filename. There is also a reference count.
+** The structure is reclaimed when the number of pointers to it drops to
+** zero.
+**
+** There are never very many files open at one time and lookups are not
+** a performance-critical path, so it is sufficient to put these
+** structures on a linked list.
+*/
+struct vxworksFileId {
+ struct vxworksFileId *pNext; /* Next in a list of them all */
+ int nRef; /* Number of references to this one */
+ int nName; /* Length of the zCanonicalName[] string */
+ char *zCanonicalName; /* Canonical filename */
+};
+
+#if OS_VXWORKS
+/*
+** All unique filenames are held on a linked list headed by this
+** variable:
+*/
+static struct vxworksFileId *vxworksFileList = 0;
+
+/*
+** Simplify a filename into its canonical form
+** by making the following changes:
+**
+** * removing any trailing and duplicate /
+** * convert /./ into just /
+** * convert /A/../ where A is any simple name into just /
+**
+** Changes are made in-place. Return the new name length.
+**
+** The original filename is in z[0..n-1]. Return the number of
+** characters in the simplified name.
+*/
+static int vxworksSimplifyName(char *z, int n){
+ int i, j;
+ while( n>1 && z[n-1]=='/' ){ n--; }
+ for(i=j=0; i0 && z[j-1]!='/' ){ j--; }
+ if( j>0 ){ j--; }
+ i += 2;
+ continue;
+ }
+ }
+ z[j++] = z[i];
+ }
+ z[j] = 0;
+ return j;
+}
+
+/*
+** Find a unique file ID for the given absolute pathname. Return
+** a pointer to the vxworksFileId object. This pointer is the unique
+** file ID.
+**
+** The nRef field of the vxworksFileId object is incremented before
+** the object is returned. A new vxworksFileId object is created
+** and added to the global list if necessary.
+**
+** If a memory allocation error occurs, return NULL.
+*/
+static struct vxworksFileId *vxworksFindFileId(const char *zAbsoluteName){
+ struct vxworksFileId *pNew; /* search key and new file ID */
+ struct vxworksFileId *pCandidate; /* For looping over existing file IDs */
+ int n; /* Length of zAbsoluteName string */
+
+ assert( zAbsoluteName[0]=='/' );
+ n = (int)strlen(zAbsoluteName);
+ pNew = sqlite3_malloc( sizeof(*pNew) + (n+1) );
+ if( pNew==0 ) return 0;
+ pNew->zCanonicalName = (char*)&pNew[1];
+ memcpy(pNew->zCanonicalName, zAbsoluteName, n+1);
+ n = vxworksSimplifyName(pNew->zCanonicalName, n);
+
+ /* Search for an existing entry that matching the canonical name.
+ ** If found, increment the reference count and return a pointer to
+ ** the existing file ID.
+ */
+ unixEnterMutex();
+ for(pCandidate=vxworksFileList; pCandidate; pCandidate=pCandidate->pNext){
+ if( pCandidate->nName==n
+ && memcmp(pCandidate->zCanonicalName, pNew->zCanonicalName, n)==0
+ ){
+ sqlite3_free(pNew);
+ pCandidate->nRef++;
+ unixLeaveMutex();
+ return pCandidate;
+ }
+ }
+
+ /* No match was found. We will make a new file ID */
+ pNew->nRef = 1;
+ pNew->nName = n;
+ pNew->pNext = vxworksFileList;
+ vxworksFileList = pNew;
+ unixLeaveMutex();
+ return pNew;
+}
+
+/*
+** Decrement the reference count on a vxworksFileId object. Free
+** the object when the reference count reaches zero.
+*/
+static void vxworksReleaseFileId(struct vxworksFileId *pId){
+ unixEnterMutex();
+ assert( pId->nRef>0 );
+ pId->nRef--;
+ if( pId->nRef==0 ){
+ struct vxworksFileId **pp;
+ for(pp=&vxworksFileList; *pp && *pp!=pId; pp = &((*pp)->pNext)){}
+ assert( *pp==pId );
+ *pp = pId->pNext;
+ sqlite3_free(pId);
+ }
+ unixLeaveMutex();
+}
+#endif /* OS_VXWORKS */
+/*************** End of Unique File ID Utility Used By VxWorks ****************
+******************************************************************************/
+
+
+/******************************************************************************
+*************************** Posix Advisory Locking ****************************
+**
+** POSIX advisory locks are broken by design. ANSI STD 1003.1 (1996)
+** section 6.5.2.2 lines 483 through 490 specify that when a process
+** sets or clears a lock, that operation overrides any prior locks set
+** by the same process. It does not explicitly say so, but this implies
+** that it overrides locks set by the same process using a different
+** file descriptor. Consider this test case:
+**
+** int fd1 = open("./file1", O_RDWR|O_CREAT, 0644);
+** int fd2 = open("./file2", O_RDWR|O_CREAT, 0644);
+**
+** Suppose ./file1 and ./file2 are really the same file (because
+** one is a hard or symbolic link to the other) then if you set
+** an exclusive lock on fd1, then try to get an exclusive lock
+** on fd2, it works. I would have expected the second lock to
+** fail since there was already a lock on the file due to fd1.
+** But not so. Since both locks came from the same process, the
+** second overrides the first, even though they were on different
+** file descriptors opened on different file names.
+**
+** This means that we cannot use POSIX locks to synchronize file access
+** among competing threads of the same process. POSIX locks will work fine
+** to synchronize access for threads in separate processes, but not
+** threads within the same process.
+**
+** To work around the problem, SQLite has to manage file locks internally
+** on its own. Whenever a new database is opened, we have to find the
+** specific inode of the database file (the inode is determined by the
+** st_dev and st_ino fields of the stat structure that fstat() fills in)
+** and check for locks already existing on that inode. When locks are
+** created or removed, we have to look at our own internal record of the
+** locks to see if another thread has previously set a lock on that same
+** inode.
+**
+** (Aside: The use of inode numbers as unique IDs does not work on VxWorks.
+** For VxWorks, we have to use the alternative unique ID system based on
+** canonical filename and implemented in the previous division.)
+**
+** The sqlite3_file structure for POSIX is no longer just an integer file
+** descriptor. It is now a structure that holds the integer file
+** descriptor and a pointer to a structure that describes the internal
+** locks on the corresponding inode. There is one locking structure
+** per inode, so if the same inode is opened twice, both unixFile structures
+** point to the same locking structure. The locking structure keeps
+** a reference count (so we will know when to delete it) and a "cnt"
+** field that tells us its internal lock status. cnt==0 means the
+** file is unlocked. cnt==-1 means the file has an exclusive lock.
+** cnt>0 means there are cnt shared locks on the file.
+**
+** Any attempt to lock or unlock a file first checks the locking
+** structure. The fcntl() system call is only invoked to set a
+** POSIX lock if the internal lock structure transitions between
+** a locked and an unlocked state.
+**
+** But wait: there are yet more problems with POSIX advisory locks.
+**
+** If you close a file descriptor that points to a file that has locks,
+** all locks on that file that are owned by the current process are
+** released. To work around this problem, each unixInodeInfo object
+** maintains a count of the number of pending locks on tha inode.
+** When an attempt is made to close an unixFile, if there are
+** other unixFile open on the same inode that are holding locks, the call
+** to close() the file descriptor is deferred until all of the locks clear.
+** The unixInodeInfo structure keeps a list of file descriptors that need to
+** be closed and that list is walked (and cleared) when the last lock
+** clears.
+**
+** Yet another problem: LinuxThreads do not play well with posix locks.
+**
+** Many older versions of linux use the LinuxThreads library which is
+** not posix compliant. Under LinuxThreads, a lock created by thread
+** A cannot be modified or overridden by a different thread B.
+** Only thread A can modify the lock. Locking behavior is correct
+** if the appliation uses the newer Native Posix Thread Library (NPTL)
+** on linux - with NPTL a lock created by thread A can override locks
+** in thread B. But there is no way to know at compile-time which
+** threading library is being used. So there is no way to know at
+** compile-time whether or not thread A can override locks on thread B.
+** One has to do a run-time check to discover the behavior of the
+** current process.
+**
+** SQLite used to support LinuxThreads. But support for LinuxThreads
+** was dropped beginning with version 3.7.0. SQLite will still work with
+** LinuxThreads provided that (1) there is no more than one connection
+** per database file in the same process and (2) database connections
+** do not move across threads.
+*/
+
+/*
+** An instance of the following structure serves as the key used
+** to locate a particular unixInodeInfo object.
+*/
+struct unixFileId {
+ dev_t dev; /* Device number */
+#if OS_VXWORKS
+ struct vxworksFileId *pId; /* Unique file ID for vxworks. */
+#else
+ ino_t ino; /* Inode number */
+#endif
+};
+
+/*
+** An instance of the following structure is allocated for each open
+** inode. Or, on LinuxThreads, there is one of these structures for
+** each inode opened by each thread.
+**
+** A single inode can have multiple file descriptors, so each unixFile
+** structure contains a pointer to an instance of this object and this
+** object keeps a count of the number of unixFile pointing to it.
+*/
+struct unixInodeInfo {
+ struct unixFileId fileId; /* The lookup key */
+ int nShared; /* Number of SHARED locks held */
+ unsigned char eFileLock; /* One of SHARED_LOCK, RESERVED_LOCK etc. */
+ unsigned char bProcessLock; /* An exclusive process lock is held */
+ int nRef; /* Number of pointers to this structure */
+ unixShmNode *pShmNode; /* Shared memory associated with this inode */
+ int nLock; /* Number of outstanding file locks */
+ UnixUnusedFd *pUnused; /* Unused file descriptors to close */
+ unixInodeInfo *pNext; /* List of all unixInodeInfo objects */
+ unixInodeInfo *pPrev; /* .... doubly linked */
+#if SQLITE_ENABLE_LOCKING_STYLE
+ unsigned long long sharedByte; /* for AFP simulated shared lock */
+#endif
+#if OS_VXWORKS
+ sem_t *pSem; /* Named POSIX semaphore */
+ char aSemName[MAX_PATHNAME+2]; /* Name of that semaphore */
+#endif
+};
+
+/*
+** A lists of all unixInodeInfo objects.
+*/
+static unixInodeInfo *inodeList = 0;
+
+/*
+**
+** This function - unixLogError_x(), is only ever called via the macro
+** unixLogError().
+**
+** It is invoked after an error occurs in an OS function and errno has been
+** set. It logs a message using sqlite3_log() containing the current value of
+** errno and, if possible, the human-readable equivalent from strerror() or
+** strerror_r().
+**
+** The first argument passed to the macro should be the error code that
+** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN).
+** The two subsequent arguments should be the name of the OS function that
+** failed (e.g. "unlink", "open") and the associated file-system path,
+** if any.
+*/
+#define unixLogError(a,b,c) unixLogErrorAtLine(a,b,c,__LINE__)
+static int unixLogErrorAtLine(
+ int errcode, /* SQLite error code */
+ const char *zFunc, /* Name of OS function that failed */
+ const char *zPath, /* File path associated with error */
+ int iLine /* Source line number where error occurred */
+){
+ char *zErr; /* Message from strerror() or equivalent */
+ int iErrno = errno; /* Saved syscall error number */
+
+ /* If this is not a threadsafe build (SQLITE_THREADSAFE==0), then use
+ ** the strerror() function to obtain the human-readable error message
+ ** equivalent to errno. Otherwise, use strerror_r().
+ */
+#if SQLITE_THREADSAFE && defined(HAVE_STRERROR_R)
+ char aErr[80];
+ memset(aErr, 0, sizeof(aErr));
+ zErr = aErr;
+
+ /* If STRERROR_R_CHAR_P (set by autoconf scripts) or __USE_GNU is defined,
+ ** assume that the system provides the GNU version of strerror_r() that
+ ** returns a pointer to a buffer containing the error message. That pointer
+ ** may point to aErr[], or it may point to some static storage somewhere.
+ ** Otherwise, assume that the system provides the POSIX version of
+ ** strerror_r(), which always writes an error message into aErr[].
+ **
+ ** If the code incorrectly assumes that it is the POSIX version that is
+ ** available, the error message will often be an empty string. Not a
+ ** huge problem. Incorrectly concluding that the GNU version is available
+ ** could lead to a segfault though.
+ */
+#if defined(STRERROR_R_CHAR_P) || defined(__USE_GNU)
+ zErr =
+# endif
+ strerror_r(iErrno, aErr, sizeof(aErr)-1);
+
+#elif SQLITE_THREADSAFE
+ /* This is a threadsafe build, but strerror_r() is not available. */
+ zErr = "";
+#else
+ /* Non-threadsafe build, use strerror(). */
+ zErr = strerror(iErrno);
+#endif
+
+ if( zPath==0 ) zPath = "";
+ sqlite3_log(errcode,
+ "os_unix.c:%d: (%d) %s(%s) - %s",
+ iLine, iErrno, zFunc, zPath, zErr
+ );
+
+ return errcode;
+}
+
+/*
+** Close a file descriptor.
+**
+** We assume that close() almost always works, since it is only in a
+** very sick application or on a very sick platform that it might fail.
+** If it does fail, simply leak the file descriptor, but do log the
+** error.
+**
+** Note that it is not safe to retry close() after EINTR since the
+** file descriptor might have already been reused by another thread.
+** So we don't even try to recover from an EINTR. Just log the error
+** and move on.
+*/
+static void robust_close(unixFile *pFile, int h, int lineno){
+ if( osClose(h) ){
+ unixLogErrorAtLine(SQLITE_IOERR_CLOSE, "close",
+ pFile ? pFile->zPath : 0, lineno);
+ }
+}
+
+/*
+** Close all file descriptors accumuated in the unixInodeInfo->pUnused list.
+*/
+static void closePendingFds(unixFile *pFile){
+ unixInodeInfo *pInode = pFile->pInode;
+ UnixUnusedFd *p;
+ UnixUnusedFd *pNext;
+ for(p=pInode->pUnused; p; p=pNext){
+ pNext = p->pNext;
+ robust_close(pFile, p->fd, __LINE__);
+ sqlite3_free(p);
+ }
+ pInode->pUnused = 0;
+}
+
+/*
+** Release a unixInodeInfo structure previously allocated by findInodeInfo().
+**
+** The mutex entered using the unixEnterMutex() function must be held
+** when this function is called.
+*/
+static void releaseInodeInfo(unixFile *pFile){
+ unixInodeInfo *pInode = pFile->pInode;
+ assert( unixMutexHeld() );
+ if( ALWAYS(pInode) ){
+ pInode->nRef--;
+ if( pInode->nRef==0 ){
+ assert( pInode->pShmNode==0 );
+ closePendingFds(pFile);
+ if( pInode->pPrev ){
+ assert( pInode->pPrev->pNext==pInode );
+ pInode->pPrev->pNext = pInode->pNext;
+ }else{
+ assert( inodeList==pInode );
+ inodeList = pInode->pNext;
+ }
+ if( pInode->pNext ){
+ assert( pInode->pNext->pPrev==pInode );
+ pInode->pNext->pPrev = pInode->pPrev;
+ }
+ sqlite3_free(pInode);
+ }
+ }
+}
+
+/*
+** Given a file descriptor, locate the unixInodeInfo object that
+** describes that file descriptor. Create a new one if necessary. The
+** return value might be uninitialized if an error occurs.
+**
+** The mutex entered using the unixEnterMutex() function must be held
+** when this function is called.
+**
+** Return an appropriate error code.
+*/
+static int findInodeInfo(
+ unixFile *pFile, /* Unix file with file desc used in the key */
+ unixInodeInfo **ppInode /* Return the unixInodeInfo object here */
+){
+ int rc; /* System call return code */
+ int fd; /* The file descriptor for pFile */
+ struct unixFileId fileId; /* Lookup key for the unixInodeInfo */
+ struct stat statbuf; /* Low-level file information */
+ unixInodeInfo *pInode = 0; /* Candidate unixInodeInfo object */
+
+ assert( unixMutexHeld() );
+
+ /* Get low-level information about the file that we can used to
+ ** create a unique name for the file.
+ */
+ fd = pFile->h;
+ rc = osFstat(fd, &statbuf);
+ if( rc!=0 ){
+ pFile->lastErrno = errno;
+#ifdef EOVERFLOW
+ if( pFile->lastErrno==EOVERFLOW ) return SQLITE_NOLFS;
+#endif
+ return SQLITE_IOERR;
+ }
+
+#ifdef __APPLE__
+ /* On OS X on an msdos filesystem, the inode number is reported
+ ** incorrectly for zero-size files. See ticket #3260. To work
+ ** around this problem (we consider it a bug in OS X, not SQLite)
+ ** we always increase the file size to 1 by writing a single byte
+ ** prior to accessing the inode number. The one byte written is
+ ** an ASCII 'S' character which also happens to be the first byte
+ ** in the header of every SQLite database. In this way, if there
+ ** is a race condition such that another thread has already populated
+ ** the first page of the database, no damage is done.
+ */
+ if( statbuf.st_size==0 && (pFile->fsFlags & SQLITE_FSFLAGS_IS_MSDOS)!=0 ){
+ do{ rc = osWrite(fd, "S", 1); }while( rc<0 && errno==EINTR );
+ if( rc!=1 ){
+ pFile->lastErrno = errno;
+ return SQLITE_IOERR;
+ }
+ rc = osFstat(fd, &statbuf);
+ if( rc!=0 ){
+ pFile->lastErrno = errno;
+ return SQLITE_IOERR;
+ }
+ }
+#endif
+
+ memset(&fileId, 0, sizeof(fileId));
+ fileId.dev = statbuf.st_dev;
+#if OS_VXWORKS
+ fileId.pId = pFile->pId;
+#else
+ fileId.ino = statbuf.st_ino;
+#endif
+ pInode = inodeList;
+ while( pInode && memcmp(&fileId, &pInode->fileId, sizeof(fileId)) ){
+ pInode = pInode->pNext;
+ }
+ if( pInode==0 ){
+ pInode = sqlite3_malloc( sizeof(*pInode) );
+ if( pInode==0 ){
+ return SQLITE_NOMEM;
+ }
+ memset(pInode, 0, sizeof(*pInode));
+ memcpy(&pInode->fileId, &fileId, sizeof(fileId));
+ pInode->nRef = 1;
+ pInode->pNext = inodeList;
+ pInode->pPrev = 0;
+ if( inodeList ) inodeList->pPrev = pInode;
+ inodeList = pInode;
+ }else{
+ pInode->nRef++;
+ }
+ *ppInode = pInode;
+ return SQLITE_OK;
+}
+
+/*
+** Return TRUE if pFile has been renamed or unlinked since it was first opened.
+*/
+static int fileHasMoved(unixFile *pFile){
+ struct stat buf;
+ return pFile->pInode!=0 &&
+ (osStat(pFile->zPath, &buf)!=0 || buf.st_ino!=pFile->pInode->fileId.ino);
+}
+
+
+/*
+** Check a unixFile that is a database. Verify the following:
+**
+** (1) There is exactly one hard link on the file
+** (2) The file is not a symbolic link
+** (3) The file has not been renamed or unlinked
+**
+** Issue sqlite3_log(SQLITE_WARNING,...) messages if anything is not right.
+*/
+static void verifyDbFile(unixFile *pFile){
+ struct stat buf;
+ int rc;
+ if( pFile->ctrlFlags & UNIXFILE_WARNED ){
+ /* One or more of the following warnings have already been issued. Do not
+ ** repeat them so as not to clutter the error log */
+ return;
+ }
+ rc = osFstat(pFile->h, &buf);
+ if( rc!=0 ){
+ sqlite3_log(SQLITE_WARNING, "cannot fstat db file %s", pFile->zPath);
+ pFile->ctrlFlags |= UNIXFILE_WARNED;
+ return;
+ }
+ if( buf.st_nlink==0 && (pFile->ctrlFlags & UNIXFILE_DELETE)==0 ){
+ sqlite3_log(SQLITE_WARNING, "file unlinked while open: %s", pFile->zPath);
+ pFile->ctrlFlags |= UNIXFILE_WARNED;
+ return;
+ }
+ if( buf.st_nlink>1 ){
+ sqlite3_log(SQLITE_WARNING, "multiple links to file: %s", pFile->zPath);
+ pFile->ctrlFlags |= UNIXFILE_WARNED;
+ return;
+ }
+ if( fileHasMoved(pFile) ){
+ sqlite3_log(SQLITE_WARNING, "file renamed while open: %s", pFile->zPath);
+ pFile->ctrlFlags |= UNIXFILE_WARNED;
+ return;
+ }
+}
+
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int unixCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+ unixEnterMutex(); /* Because pFile->pInode is shared across threads */
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->pInode->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it.
+ */
+#ifndef __DJGPP__
+ if( !reserved && !pFile->pInode->bProcessLock ){
+ struct flock lock;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = RESERVED_BYTE;
+ lock.l_len = 1;
+ lock.l_type = F_WRLCK;
+ if( osFcntl(pFile->h, F_GETLK, &lock) ){
+ rc = SQLITE_IOERR_CHECKRESERVEDLOCK;
+ pFile->lastErrno = errno;
+ } else if( lock.l_type!=F_UNLCK ){
+ reserved = 1;
+ }
+ }
+#endif
+
+ unixLeaveMutex();
+ OSTRACE(("TEST WR-LOCK %d %d %d (unix)\n", pFile->h, rc, reserved));
+
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Attempt to set a system-lock on the file pFile. The lock is
+** described by pLock.
+**
+** If the pFile was opened read/write from unix-excl, then the only lock
+** ever obtained is an exclusive lock, and it is obtained exactly once
+** the first time any lock is attempted. All subsequent system locking
+** operations become no-ops. Locking operations still happen internally,
+** in order to coordinate access between separate database connections
+** within this process, but all of that is handled in memory and the
+** operating system does not participate.
+**
+** This function is a pass-through to fcntl(F_SETLK) if pFile is using
+** any VFS other than "unix-excl" or if pFile is opened on "unix-excl"
+** and is read-only.
+**
+** Zero is returned if the call completes successfully, or -1 if a call
+** to fcntl() fails. In this case, errno is set appropriately (by fcntl()).
+*/
+static int unixFileLock(unixFile *pFile, struct flock *pLock){
+ int rc;
+ unixInodeInfo *pInode = pFile->pInode;
+ assert( unixMutexHeld() );
+ assert( pInode!=0 );
+ if( ((pFile->ctrlFlags & UNIXFILE_EXCL)!=0 || pInode->bProcessLock)
+ && ((pFile->ctrlFlags & UNIXFILE_RDONLY)==0)
+ ){
+ if( pInode->bProcessLock==0 ){
+ struct flock lock;
+ assert( pInode->nLock==0 );
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ lock.l_type = F_WRLCK;
+ rc = osFcntl(pFile->h, F_SETLK, &lock);
+ if( rc<0 ) return rc;
+ pInode->bProcessLock = 1;
+ pInode->nLock++;
+ }else{
+ rc = 0;
+ }
+ }else{
+ rc = osFcntl(pFile->h, F_SETLK, pLock);
+ }
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int unixLock(sqlite3_file *id, int eFileLock){
+ /* The following describes the implementation of the various locks and
+ ** lock transitions in terms of the POSIX advisory shared and exclusive
+ ** lock primitives (called read-locks and write-locks below, to avoid
+ ** confusion with SQLite lock names). The algorithms are complicated
+ ** slightly in order to be compatible with windows systems simultaneously
+ ** accessing the same database file, in case that is ever required.
+ **
+ ** Symbols defined in os.h indentify the 'pending byte' and the 'reserved
+ ** byte', each single bytes at well known offsets, and the 'shared byte
+ ** range', a range of 510 bytes at a well known offset.
+ **
+ ** To obtain a SHARED lock, a read-lock is obtained on the 'pending
+ ** byte'. If this is successful, a random byte from the 'shared byte
+ ** range' is read-locked and the lock on the 'pending byte' released.
+ **
+ ** A process may only obtain a RESERVED lock after it has a SHARED lock.
+ ** A RESERVED lock is implemented by grabbing a write-lock on the
+ ** 'reserved byte'.
+ **
+ ** A process may only obtain a PENDING lock after it has obtained a
+ ** SHARED lock. A PENDING lock is implemented by obtaining a write-lock
+ ** on the 'pending byte'. This ensures that no new SHARED locks can be
+ ** obtained, but existing SHARED locks are allowed to persist. A process
+ ** does not have to obtain a RESERVED lock on the way to a PENDING lock.
+ ** This property is used by the algorithm for rolling back a journal file
+ ** after a crash.
+ **
+ ** An EXCLUSIVE lock, obtained after a PENDING lock is held, is
+ ** implemented by obtaining a write-lock on the entire 'shared byte
+ ** range'. Since all other locks require a read-lock on one of the bytes
+ ** within this range, this ensures that no other locks are held on the
+ ** database.
+ **
+ ** The reason a single byte cannot be used instead of the 'shared byte
+ ** range' is that some versions of windows do not support read-locks. By
+ ** locking a random byte from a range, concurrent SHARED locks may exist
+ ** even if the locking primitive used is always a write-lock.
+ */
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode;
+ struct flock lock;
+ int tErrno = 0;
+
+ assert( pFile );
+ OSTRACE(("LOCK %d %s was %s(%s,%d) pid=%d (unix)\n", pFile->h,
+ azFileLock(eFileLock), azFileLock(pFile->eFileLock),
+ azFileLock(pFile->pInode->eFileLock), pFile->pInode->nShared , getpid()));
+
+ /* If there is already a lock of this type or more restrictive on the
+ ** unixFile, do nothing. Don't use the end_lock: exit path, as
+ ** unixEnterMutex() hasn't been called yet.
+ */
+ if( pFile->eFileLock>=eFileLock ){
+ OSTRACE(("LOCK %d %s ok (already held) (unix)\n", pFile->h,
+ azFileLock(eFileLock)));
+ return SQLITE_OK;
+ }
+
+ /* Make sure the locking sequence is correct.
+ ** (1) We never move from unlocked to anything higher than shared lock.
+ ** (2) SQLite never explicitly requests a pendig lock.
+ ** (3) A shared lock is always held when a reserve lock is requested.
+ */
+ assert( pFile->eFileLock!=NO_LOCK || eFileLock==SHARED_LOCK );
+ assert( eFileLock!=PENDING_LOCK );
+ assert( eFileLock!=RESERVED_LOCK || pFile->eFileLock==SHARED_LOCK );
+
+ /* This mutex is needed because pFile->pInode is shared across threads
+ */
+ unixEnterMutex();
+ pInode = pFile->pInode;
+
+ /* If some thread using this PID has a lock via a different unixFile*
+ ** handle that precludes the requested lock, return BUSY.
+ */
+ if( (pFile->eFileLock!=pInode->eFileLock &&
+ (pInode->eFileLock>=PENDING_LOCK || eFileLock>SHARED_LOCK))
+ ){
+ rc = SQLITE_BUSY;
+ goto end_lock;
+ }
+
+ /* If a SHARED lock is requested, and some thread using this PID already
+ ** has a SHARED or RESERVED lock, then increment reference counts and
+ ** return SQLITE_OK.
+ */
+ if( eFileLock==SHARED_LOCK &&
+ (pInode->eFileLock==SHARED_LOCK || pInode->eFileLock==RESERVED_LOCK) ){
+ assert( eFileLock==SHARED_LOCK );
+ assert( pFile->eFileLock==0 );
+ assert( pInode->nShared>0 );
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nShared++;
+ pInode->nLock++;
+ goto end_lock;
+ }
+
+
+ /* A PENDING lock is needed before acquiring a SHARED lock and before
+ ** acquiring an EXCLUSIVE lock. For the SHARED lock, the PENDING will
+ ** be released.
+ */
+ lock.l_len = 1L;
+ lock.l_whence = SEEK_SET;
+ if( eFileLock==SHARED_LOCK
+ || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLocklastErrno = tErrno;
+ }
+ goto end_lock;
+ }
+ }
+
+
+ /* If control gets to this point, then actually go ahead and make
+ ** operating system calls for the specified lock.
+ */
+ if( eFileLock==SHARED_LOCK ){
+ assert( pInode->nShared==0 );
+ assert( pInode->eFileLock==0 );
+ assert( rc==SQLITE_OK );
+
+ /* Now get the read-lock */
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ if( unixFileLock(pFile, &lock) ){
+ tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ }
+
+ /* Drop the temporary PENDING lock */
+ lock.l_start = PENDING_BYTE;
+ lock.l_len = 1L;
+ lock.l_type = F_UNLCK;
+ if( unixFileLock(pFile, &lock) && rc==SQLITE_OK ){
+ /* This could happen with a network mount */
+ tErrno = errno;
+ rc = SQLITE_IOERR_UNLOCK;
+ }
+
+ if( rc ){
+ if( rc!=SQLITE_BUSY ){
+ pFile->lastErrno = tErrno;
+ }
+ goto end_lock;
+ }else{
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nLock++;
+ pInode->nShared = 1;
+ }
+ }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
+ /* We are trying for an exclusive lock but another thread in this
+ ** same process is still holding a shared lock. */
+ rc = SQLITE_BUSY;
+ }else{
+ /* The request was for a RESERVED or EXCLUSIVE lock. It is
+ ** assumed that there is a SHARED or greater lock on the file
+ ** already.
+ */
+ assert( 0!=pFile->eFileLock );
+ lock.l_type = F_WRLCK;
+
+ assert( eFileLock==RESERVED_LOCK || eFileLock==EXCLUSIVE_LOCK );
+ if( eFileLock==RESERVED_LOCK ){
+ lock.l_start = RESERVED_BYTE;
+ lock.l_len = 1L;
+ }else{
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ }
+
+ if( unixFileLock(pFile, &lock) ){
+ tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( rc!=SQLITE_BUSY ){
+ pFile->lastErrno = tErrno;
+ }
+ }
+ }
+
+
+#ifdef SQLITE_DEBUG
+ /* Set up the transaction-counter change checking flags when
+ ** transitioning from a SHARED to a RESERVED lock. The change
+ ** from SHARED to RESERVED marks the beginning of a normal
+ ** write operation (not a hot journal rollback).
+ */
+ if( rc==SQLITE_OK
+ && pFile->eFileLock<=SHARED_LOCK
+ && eFileLock==RESERVED_LOCK
+ ){
+ pFile->transCntrChng = 0;
+ pFile->dbUpdate = 0;
+ pFile->inNormalWrite = 1;
+ }
+#endif
+
+
+ if( rc==SQLITE_OK ){
+ pFile->eFileLock = eFileLock;
+ pInode->eFileLock = eFileLock;
+ }else if( eFileLock==EXCLUSIVE_LOCK ){
+ pFile->eFileLock = PENDING_LOCK;
+ pInode->eFileLock = PENDING_LOCK;
+ }
+
+end_lock:
+ unixLeaveMutex();
+ OSTRACE(("LOCK %d %s %s (unix)\n", pFile->h, azFileLock(eFileLock),
+ rc==SQLITE_OK ? "ok" : "failed"));
+ return rc;
+}
+
+/*
+** Add the file descriptor used by file handle pFile to the corresponding
+** pUnused list.
+*/
+static void setPendingFd(unixFile *pFile){
+ unixInodeInfo *pInode = pFile->pInode;
+ UnixUnusedFd *p = pFile->pUnused;
+ p->pNext = pInode->pUnused;
+ pInode->pUnused = p;
+ pFile->h = -1;
+ pFile->pUnused = 0;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+**
+** If handleNFSUnlock is true, then on downgrading an EXCLUSIVE_LOCK to SHARED
+** the byte range is divided into 2 parts and the first part is unlocked then
+** set to a read lock, then the other part is simply unlocked. This works
+** around a bug in BSD NFS lockd (also seen on MacOSX 10.3+) that fails to
+** remove the write lock on a region when a read lock is set.
+*/
+static int posixUnlock(sqlite3_file *id, int eFileLock, int handleNFSUnlock){
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode;
+ struct flock lock;
+ int rc = SQLITE_OK;
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d(%d,%d) pid=%d (unix)\n", pFile->h, eFileLock,
+ pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
+ getpid()));
+
+ assert( eFileLock<=SHARED_LOCK );
+ if( pFile->eFileLock<=eFileLock ){
+ return SQLITE_OK;
+ }
+ unixEnterMutex();
+ pInode = pFile->pInode;
+ assert( pInode->nShared!=0 );
+ if( pFile->eFileLock>SHARED_LOCK ){
+ assert( pInode->eFileLock==pFile->eFileLock );
+
+#ifdef SQLITE_DEBUG
+ /* When reducing a lock such that other processes can start
+ ** reading the database file again, make sure that the
+ ** transaction counter was updated if any part of the database
+ ** file changed. If the transaction counter is not updated,
+ ** other connections to the same file might not realize that
+ ** the file has changed and hence might not know to flush their
+ ** cache. The use of a stale cache can lead to database corruption.
+ */
+ pFile->inNormalWrite = 0;
+#endif
+
+ /* downgrading to a shared lock on NFS involves clearing the write lock
+ ** before establishing the readlock - to avoid a race condition we downgrade
+ ** the lock in 2 blocks, so that part of the range will be covered by a
+ ** write lock until the rest is covered by a read lock:
+ ** 1: [WWWWW]
+ ** 2: [....W]
+ ** 3: [RRRRW]
+ ** 4: [RRRR.]
+ */
+ if( eFileLock==SHARED_LOCK ){
+
+#if !defined(__APPLE__) || !SQLITE_ENABLE_LOCKING_STYLE
+ (void)handleNFSUnlock;
+ assert( handleNFSUnlock==0 );
+#endif
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+ if( handleNFSUnlock ){
+ int tErrno; /* Error code from system call errors */
+ off_t divSize = SHARED_SIZE - 1;
+
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = divSize;
+ if( unixFileLock(pFile, &lock)==(-1) ){
+ tErrno = errno;
+ rc = SQLITE_IOERR_UNLOCK;
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ goto end_unlock;
+ }
+ lock.l_type = F_RDLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = divSize;
+ if( unixFileLock(pFile, &lock)==(-1) ){
+ tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_RDLOCK);
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ goto end_unlock;
+ }
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST+divSize;
+ lock.l_len = SHARED_SIZE-divSize;
+ if( unixFileLock(pFile, &lock)==(-1) ){
+ tErrno = errno;
+ rc = SQLITE_IOERR_UNLOCK;
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ goto end_unlock;
+ }
+ }else
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+ {
+ lock.l_type = F_RDLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = SHARED_FIRST;
+ lock.l_len = SHARED_SIZE;
+ if( unixFileLock(pFile, &lock) ){
+ /* In theory, the call to unixFileLock() cannot fail because another
+ ** process is holding an incompatible lock. If it does, this
+ ** indicates that the other process is not following the locking
+ ** protocol. If this happens, return SQLITE_IOERR_RDLOCK. Returning
+ ** SQLITE_BUSY would confuse the upper layer (in practice it causes
+ ** an assert to fail). */
+ rc = SQLITE_IOERR_RDLOCK;
+ pFile->lastErrno = errno;
+ goto end_unlock;
+ }
+ }
+ }
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = PENDING_BYTE;
+ lock.l_len = 2L; assert( PENDING_BYTE+1==RESERVED_BYTE );
+ if( unixFileLock(pFile, &lock)==0 ){
+ pInode->eFileLock = SHARED_LOCK;
+ }else{
+ rc = SQLITE_IOERR_UNLOCK;
+ pFile->lastErrno = errno;
+ goto end_unlock;
+ }
+ }
+ if( eFileLock==NO_LOCK ){
+ /* Decrement the shared lock counter. Release the lock using an
+ ** OS call only when all threads in this same process have released
+ ** the lock.
+ */
+ pInode->nShared--;
+ if( pInode->nShared==0 ){
+ lock.l_type = F_UNLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = lock.l_len = 0L;
+ if( unixFileLock(pFile, &lock)==0 ){
+ pInode->eFileLock = NO_LOCK;
+ }else{
+ rc = SQLITE_IOERR_UNLOCK;
+ pFile->lastErrno = errno;
+ pInode->eFileLock = NO_LOCK;
+ pFile->eFileLock = NO_LOCK;
+ }
+ }
+
+ /* Decrement the count of locks against this same file. When the
+ ** count reaches zero, close any other file descriptors whose close
+ ** was deferred because of outstanding locks.
+ */
+ pInode->nLock--;
+ assert( pInode->nLock>=0 );
+ if( pInode->nLock==0 ){
+ closePendingFds(pFile);
+ }
+ }
+
+end_unlock:
+ unixLeaveMutex();
+ if( rc==SQLITE_OK ) pFile->eFileLock = eFileLock;
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int unixUnlock(sqlite3_file *id, int eFileLock){
+#if SQLITE_MAX_MMAP_SIZE>0
+ assert( eFileLock==SHARED_LOCK || ((unixFile *)id)->nFetchOut==0 );
+#endif
+ return posixUnlock(id, eFileLock, 0);
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+static int unixMapfile(unixFile *pFd, i64 nByte);
+static void unixUnmapfile(unixFile *pFd);
+#endif
+
+/*
+** This function performs the parts of the "close file" operation
+** common to all locking schemes. It closes the directory and file
+** handles, if they are valid, and sets all fields of the unixFile
+** structure to 0.
+**
+** It is *not* necessary to hold the mutex when this routine is called,
+** even on VxWorks. A mutex will be acquired on VxWorks by the
+** vxworksReleaseFileId() routine.
+*/
+static int closeUnixFile(sqlite3_file *id){
+ unixFile *pFile = (unixFile*)id;
+#if SQLITE_MAX_MMAP_SIZE>0
+ unixUnmapfile(pFile);
+#endif
+ if( pFile->h>=0 ){
+ robust_close(pFile, pFile->h, __LINE__);
+ pFile->h = -1;
+ }
+#if OS_VXWORKS
+ if( pFile->pId ){
+ if( pFile->ctrlFlags & UNIXFILE_DELETE ){
+ osUnlink(pFile->pId->zCanonicalName);
+ }
+ vxworksReleaseFileId(pFile->pId);
+ pFile->pId = 0;
+ }
+#endif
+ OSTRACE(("CLOSE %-3d\n", pFile->h));
+ OpenCounter(-1);
+ sqlite3_free(pFile->pUnused);
+ memset(pFile, 0, sizeof(unixFile));
+ return SQLITE_OK;
+}
+
+/*
+** Close a file.
+*/
+static int unixClose(sqlite3_file *id){
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile *)id;
+ verifyDbFile(pFile);
+ unixUnlock(id, NO_LOCK);
+ unixEnterMutex();
+
+ /* unixFile.pInode is always valid here. Otherwise, a different close
+ ** routine (e.g. nolockClose()) would be called instead.
+ */
+ assert( pFile->pInode->nLock>0 || pFile->pInode->bProcessLock==0 );
+ if( ALWAYS(pFile->pInode) && pFile->pInode->nLock ){
+ /* If there are outstanding locks, do not actually close the file just
+ ** yet because that would clear those locks. Instead, add the file
+ ** descriptor to pInode->pUnused list. It will be automatically closed
+ ** when the last lock is cleared.
+ */
+ setPendingFd(pFile);
+ }
+ releaseInodeInfo(pFile);
+ rc = closeUnixFile(id);
+ unixLeaveMutex();
+ return rc;
+}
+
+/************** End of the posix advisory lock implementation *****************
+******************************************************************************/
+
+/******************************************************************************
+****************************** No-op Locking **********************************
+**
+** Of the various locking implementations available, this is by far the
+** simplest: locking is ignored. No attempt is made to lock the database
+** file for reading or writing.
+**
+** This locking mode is appropriate for use on read-only databases
+** (ex: databases that are burned into CD-ROM, for example.) It can
+** also be used if the application employs some external mechanism to
+** prevent simultaneous access of the same database by two or more
+** database connections. But there is a serious risk of database
+** corruption if this locking mode is used in situations where multiple
+** database connections are accessing the same database file at the same
+** time and one or more of those connections are writing.
+*/
+
+static int nolockCheckReservedLock(sqlite3_file *NotUsed, int *pResOut){
+ UNUSED_PARAMETER(NotUsed);
+ *pResOut = 0;
+ return SQLITE_OK;
+}
+static int nolockLock(sqlite3_file *NotUsed, int NotUsed2){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ return SQLITE_OK;
+}
+static int nolockUnlock(sqlite3_file *NotUsed, int NotUsed2){
+ UNUSED_PARAMETER2(NotUsed, NotUsed2);
+ return SQLITE_OK;
+}
+
+/*
+** Close the file.
+*/
+static int nolockClose(sqlite3_file *id) {
+ return closeUnixFile(id);
+}
+
+/******************* End of the no-op lock implementation *********************
+******************************************************************************/
+
+/******************************************************************************
+************************* Begin dot-file Locking ******************************
+**
+** The dotfile locking implementation uses the existence of separate lock
+** files (really a directory) to control access to the database. This works
+** on just about every filesystem imaginable. But there are serious downsides:
+**
+** (1) There is zero concurrency. A single reader blocks all other
+** connections from reading or writing the database.
+**
+** (2) An application crash or power loss can leave stale lock files
+** sitting around that need to be cleared manually.
+**
+** Nevertheless, a dotlock is an appropriate locking mode for use if no
+** other locking strategy is available.
+**
+** Dotfile locking works by creating a subdirectory in the same directory as
+** the database and with the same name but with a ".lock" extension added.
+** The existence of a lock directory implies an EXCLUSIVE lock. All other
+** lock types (SHARED, RESERVED, PENDING) are mapped into EXCLUSIVE.
+*/
+
+/*
+** The file suffix added to the data base filename in order to create the
+** lock directory.
+*/
+#define DOTLOCK_SUFFIX ".lock"
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+**
+** In dotfile locking, either a lock exists or it does not. So in this
+** variation of CheckReservedLock(), *pResOut is set to true if any lock
+** is held on the file and false if the file is unlocked.
+*/
+static int dotlockCheckReservedLock(sqlite3_file *id, int *pResOut) {
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->eFileLock>SHARED_LOCK ){
+ /* Either this connection or some other connection in the same process
+ ** holds a lock on the file. No need to check further. */
+ reserved = 1;
+ }else{
+ /* The lock is held if and only if the lockfile exists */
+ const char *zLockFile = (const char*)pFile->lockingContext;
+ reserved = osAccess(zLockFile, 0)==0;
+ }
+ OSTRACE(("TEST WR-LOCK %d %d %d (dotlock)\n", pFile->h, rc, reserved));
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+**
+** With dotfile locking, we really only support state (4): EXCLUSIVE.
+** But we track the other locking levels internally.
+*/
+static int dotlockLock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ char *zLockFile = (char *)pFile->lockingContext;
+ int rc = SQLITE_OK;
+
+
+ /* If we have any lock, then the lock file already exists. All we have
+ ** to do is adjust our internal record of the lock level.
+ */
+ if( pFile->eFileLock > NO_LOCK ){
+ pFile->eFileLock = eFileLock;
+ /* Always update the timestamp on the old file */
+#ifdef HAVE_UTIME
+ utime(zLockFile, NULL);
+#else
+ utimes(zLockFile, NULL);
+#endif
+ return SQLITE_OK;
+ }
+
+ /* grab an exclusive lock */
+ rc = osMkdir(zLockFile, 0777);
+ if( rc<0 ){
+ /* failed to open/create the lock directory */
+ int tErrno = errno;
+ if( EEXIST == tErrno ){
+ rc = SQLITE_BUSY;
+ } else {
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ }
+ return rc;
+ }
+
+ /* got it, set the type and return ok */
+ pFile->eFileLock = eFileLock;
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+**
+** When the locking level reaches NO_LOCK, delete the lock file.
+*/
+static int dotlockUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ char *zLockFile = (char *)pFile->lockingContext;
+ int rc;
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d pid=%d (dotlock)\n", pFile->h, eFileLock,
+ pFile->eFileLock, getpid()));
+ assert( eFileLock<=SHARED_LOCK );
+
+ /* no-op if possible */
+ if( pFile->eFileLock==eFileLock ){
+ return SQLITE_OK;
+ }
+
+ /* To downgrade to shared, simply update our internal notion of the
+ ** lock state. No need to mess with the file on disk.
+ */
+ if( eFileLock==SHARED_LOCK ){
+ pFile->eFileLock = SHARED_LOCK;
+ return SQLITE_OK;
+ }
+
+ /* To fully unlock the database, delete the lock file */
+ assert( eFileLock==NO_LOCK );
+ rc = osRmdir(zLockFile);
+ if( rc<0 && errno==ENOTDIR ) rc = osUnlink(zLockFile);
+ if( rc<0 ){
+ int tErrno = errno;
+ rc = 0;
+ if( ENOENT != tErrno ){
+ rc = SQLITE_IOERR_UNLOCK;
+ }
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ return rc;
+ }
+ pFile->eFileLock = NO_LOCK;
+ return SQLITE_OK;
+}
+
+/*
+** Close a file. Make sure the lock has been released before closing.
+*/
+static int dotlockClose(sqlite3_file *id) {
+ int rc = SQLITE_OK;
+ if( id ){
+ unixFile *pFile = (unixFile*)id;
+ dotlockUnlock(id, NO_LOCK);
+ sqlite3_free(pFile->lockingContext);
+ rc = closeUnixFile(id);
+ }
+ return rc;
+}
+/****************** End of the dot-file lock implementation *******************
+******************************************************************************/
+
+/******************************************************************************
+************************** Begin flock Locking ********************************
+**
+** Use the flock() system call to do file locking.
+**
+** flock() locking is like dot-file locking in that the various
+** fine-grain locking levels supported by SQLite are collapsed into
+** a single exclusive lock. In other words, SHARED, RESERVED, and
+** PENDING locks are the same thing as an EXCLUSIVE lock. SQLite
+** still works when you do this, but concurrency is reduced since
+** only a single process can be reading the database at a time.
+**
+** Omit this section if SQLITE_ENABLE_LOCKING_STYLE is turned off or if
+** compiling for VXWORKS.
+*/
+#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
+
+/*
+** Retry flock() calls that fail with EINTR
+*/
+#ifdef EINTR
+static int robust_flock(int fd, int op){
+ int rc;
+ do{ rc = flock(fd,op); }while( rc<0 && errno==EINTR );
+ return rc;
+}
+#else
+# define robust_flock(a,b) flock(a,b)
+#endif
+
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int flockCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it. */
+ if( !reserved ){
+ /* attempt to get the lock */
+ int lrc = robust_flock(pFile->h, LOCK_EX | LOCK_NB);
+ if( !lrc ){
+ /* got the lock, unlock it */
+ lrc = robust_flock(pFile->h, LOCK_UN);
+ if ( lrc ) {
+ int tErrno = errno;
+ /* unlock failed with an error */
+ lrc = SQLITE_IOERR_UNLOCK;
+ if( IS_LOCK_ERROR(lrc) ){
+ pFile->lastErrno = tErrno;
+ rc = lrc;
+ }
+ }
+ } else {
+ int tErrno = errno;
+ reserved = 1;
+ /* someone else might have it reserved */
+ lrc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( IS_LOCK_ERROR(lrc) ){
+ pFile->lastErrno = tErrno;
+ rc = lrc;
+ }
+ }
+ }
+ OSTRACE(("TEST WR-LOCK %d %d %d (flock)\n", pFile->h, rc, reserved));
+
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+ if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
+ rc = SQLITE_OK;
+ reserved=1;
+ }
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** flock() only really support EXCLUSIVE locks. We track intermediate
+** lock states in the sqlite3_file structure, but all locks SHARED or
+** above are really EXCLUSIVE locks and exclude all other processes from
+** access the file.
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int flockLock(sqlite3_file *id, int eFileLock) {
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+
+ assert( pFile );
+
+ /* if we already have a lock, it is exclusive.
+ ** Just adjust level and punt on outta here. */
+ if (pFile->eFileLock > NO_LOCK) {
+ pFile->eFileLock = eFileLock;
+ return SQLITE_OK;
+ }
+
+ /* grab an exclusive lock */
+
+ if (robust_flock(pFile->h, LOCK_EX | LOCK_NB)) {
+ int tErrno = errno;
+ /* didn't get, must be busy */
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ } else {
+ /* got it, set the type and return ok */
+ pFile->eFileLock = eFileLock;
+ }
+ OSTRACE(("LOCK %d %s %s (flock)\n", pFile->h, azFileLock(eFileLock),
+ rc==SQLITE_OK ? "ok" : "failed"));
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+ if( (rc & SQLITE_IOERR) == SQLITE_IOERR ){
+ rc = SQLITE_BUSY;
+ }
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+ return rc;
+}
+
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int flockUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d pid=%d (flock)\n", pFile->h, eFileLock,
+ pFile->eFileLock, getpid()));
+ assert( eFileLock<=SHARED_LOCK );
+
+ /* no-op if possible */
+ if( pFile->eFileLock==eFileLock ){
+ return SQLITE_OK;
+ }
+
+ /* shared can just be set because we always have an exclusive */
+ if (eFileLock==SHARED_LOCK) {
+ pFile->eFileLock = eFileLock;
+ return SQLITE_OK;
+ }
+
+ /* no, really, unlock. */
+ if( robust_flock(pFile->h, LOCK_UN) ){
+#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
+ return SQLITE_OK;
+#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
+ return SQLITE_IOERR_UNLOCK;
+ }else{
+ pFile->eFileLock = NO_LOCK;
+ return SQLITE_OK;
+ }
+}
+
+/*
+** Close a file.
+*/
+static int flockClose(sqlite3_file *id) {
+ int rc = SQLITE_OK;
+ if( id ){
+ flockUnlock(id, NO_LOCK);
+ rc = closeUnixFile(id);
+ }
+ return rc;
+}
+
+#endif /* SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORK */
+
+/******************* End of the flock lock implementation *********************
+******************************************************************************/
+
+/******************************************************************************
+************************ Begin Named Semaphore Locking ************************
+**
+** Named semaphore locking is only supported on VxWorks.
+**
+** Semaphore locking is like dot-lock and flock in that it really only
+** supports EXCLUSIVE locking. Only a single process can read or write
+** the database file at a time. This reduces potential concurrency, but
+** makes the lock implementation much easier.
+*/
+#if OS_VXWORKS
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int semCheckReservedLock(sqlite3_file *id, int *pResOut) {
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it. */
+ if( !reserved ){
+ sem_t *pSem = pFile->pInode->pSem;
+ struct stat statBuf;
+
+ if( sem_trywait(pSem)==-1 ){
+ int tErrno = errno;
+ if( EAGAIN != tErrno ){
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_CHECKRESERVEDLOCK);
+ pFile->lastErrno = tErrno;
+ } else {
+ /* someone else has the lock when we are in NO_LOCK */
+ reserved = (pFile->eFileLock < SHARED_LOCK);
+ }
+ }else{
+ /* we could have it if we want it */
+ sem_post(pSem);
+ }
+ }
+ OSTRACE(("TEST WR-LOCK %d %d %d (sem)\n", pFile->h, rc, reserved));
+
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** Semaphore locks only really support EXCLUSIVE locks. We track intermediate
+** lock states in the sqlite3_file structure, but all locks SHARED or
+** above are really EXCLUSIVE locks and exclude all other processes from
+** access the file.
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int semLock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ int fd;
+ sem_t *pSem = pFile->pInode->pSem;
+ int rc = SQLITE_OK;
+
+ /* if we already have a lock, it is exclusive.
+ ** Just adjust level and punt on outta here. */
+ if (pFile->eFileLock > NO_LOCK) {
+ pFile->eFileLock = eFileLock;
+ rc = SQLITE_OK;
+ goto sem_end_lock;
+ }
+
+ /* lock semaphore now but bail out when already locked. */
+ if( sem_trywait(pSem)==-1 ){
+ rc = SQLITE_BUSY;
+ goto sem_end_lock;
+ }
+
+ /* got it, set the type and return ok */
+ pFile->eFileLock = eFileLock;
+
+ sem_end_lock:
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int semUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ sem_t *pSem = pFile->pInode->pSem;
+
+ assert( pFile );
+ assert( pSem );
+ OSTRACE(("UNLOCK %d %d was %d pid=%d (sem)\n", pFile->h, eFileLock,
+ pFile->eFileLock, getpid()));
+ assert( eFileLock<=SHARED_LOCK );
+
+ /* no-op if possible */
+ if( pFile->eFileLock==eFileLock ){
+ return SQLITE_OK;
+ }
+
+ /* shared can just be set because we always have an exclusive */
+ if (eFileLock==SHARED_LOCK) {
+ pFile->eFileLock = eFileLock;
+ return SQLITE_OK;
+ }
+
+ /* no, really unlock. */
+ if ( sem_post(pSem)==-1 ) {
+ int rc, tErrno = errno;
+ rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ return rc;
+ }
+ pFile->eFileLock = NO_LOCK;
+ return SQLITE_OK;
+}
+
+/*
+ ** Close a file.
+ */
+static int semClose(sqlite3_file *id) {
+ if( id ){
+ unixFile *pFile = (unixFile*)id;
+ semUnlock(id, NO_LOCK);
+ assert( pFile );
+ unixEnterMutex();
+ releaseInodeInfo(pFile);
+ unixLeaveMutex();
+ closeUnixFile(id);
+ }
+ return SQLITE_OK;
+}
+
+#endif /* OS_VXWORKS */
+/*
+** Named semaphore locking is only available on VxWorks.
+**
+*************** End of the named semaphore lock implementation ****************
+******************************************************************************/
+
+
+/******************************************************************************
+*************************** Begin AFP Locking *********************************
+**
+** AFP is the Apple Filing Protocol. AFP is a network filesystem found
+** on Apple Macintosh computers - both OS9 and OSX.
+**
+** Third-party implementations of AFP are available. But this code here
+** only works on OSX.
+*/
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+/*
+** The afpLockingContext structure contains all afp lock specific state
+*/
+typedef struct afpLockingContext afpLockingContext;
+struct afpLockingContext {
+ int reserved;
+ const char *dbPath; /* Name of the open file */
+};
+
+struct ByteRangeLockPB2
+{
+ unsigned long long offset; /* offset to first byte to lock */
+ unsigned long long length; /* nbr of bytes to lock */
+ unsigned long long retRangeStart; /* nbr of 1st byte locked if successful */
+ unsigned char unLockFlag; /* 1 = unlock, 0 = lock */
+ unsigned char startEndFlag; /* 1=rel to end of fork, 0=rel to start */
+ int fd; /* file desc to assoc this lock with */
+};
+
+#define afpfsByteRangeLock2FSCTL _IOWR('z', 23, struct ByteRangeLockPB2)
+
+/*
+** This is a utility for setting or clearing a bit-range lock on an
+** AFP filesystem.
+**
+** Return SQLITE_OK on success, SQLITE_BUSY on failure.
+*/
+static int afpSetLock(
+ const char *path, /* Name of the file to be locked or unlocked */
+ unixFile *pFile, /* Open file descriptor on path */
+ unsigned long long offset, /* First byte to be locked */
+ unsigned long long length, /* Number of bytes to lock */
+ int setLockFlag /* True to set lock. False to clear lock */
+){
+ struct ByteRangeLockPB2 pb;
+ int err;
+
+ pb.unLockFlag = setLockFlag ? 0 : 1;
+ pb.startEndFlag = 0;
+ pb.offset = offset;
+ pb.length = length;
+ pb.fd = pFile->h;
+
+ OSTRACE(("AFPSETLOCK [%s] for %d%s in range %llx:%llx\n",
+ (setLockFlag?"ON":"OFF"), pFile->h, (pb.fd==-1?"[testval-1]":""),
+ offset, length));
+ err = fsctl(path, afpfsByteRangeLock2FSCTL, &pb, 0);
+ if ( err==-1 ) {
+ int rc;
+ int tErrno = errno;
+ OSTRACE(("AFPSETLOCK failed to fsctl() '%s' %d %s\n",
+ path, tErrno, strerror(tErrno)));
+#ifdef SQLITE_IGNORE_AFP_LOCK_ERRORS
+ rc = SQLITE_BUSY;
+#else
+ rc = sqliteErrorFromPosixError(tErrno,
+ setLockFlag ? SQLITE_IOERR_LOCK : SQLITE_IOERR_UNLOCK);
+#endif /* SQLITE_IGNORE_AFP_LOCK_ERRORS */
+ if( IS_LOCK_ERROR(rc) ){
+ pFile->lastErrno = tErrno;
+ }
+ return rc;
+ } else {
+ return SQLITE_OK;
+ }
+}
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int afpCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int rc = SQLITE_OK;
+ int reserved = 0;
+ unixFile *pFile = (unixFile*)id;
+ afpLockingContext *context;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
+ assert( pFile );
+ context = (afpLockingContext *) pFile->lockingContext;
+ if( context->reserved ){
+ *pResOut = 1;
+ return SQLITE_OK;
+ }
+ unixEnterMutex(); /* Because pFile->pInode is shared across threads */
+
+ /* Check if a thread in this process holds such a lock */
+ if( pFile->pInode->eFileLock>SHARED_LOCK ){
+ reserved = 1;
+ }
+
+ /* Otherwise see if some other process holds it.
+ */
+ if( !reserved ){
+ /* lock the RESERVED byte */
+ int lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);
+ if( SQLITE_OK==lrc ){
+ /* if we succeeded in taking the reserved lock, unlock it to restore
+ ** the original state */
+ lrc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
+ } else {
+ /* if we failed to get the lock then someone else must have it */
+ reserved = 1;
+ }
+ if( IS_LOCK_ERROR(lrc) ){
+ rc=lrc;
+ }
+ }
+
+ unixLeaveMutex();
+ OSTRACE(("TEST WR-LOCK %d %d %d (afp)\n", pFile->h, rc, reserved));
+
+ *pResOut = reserved;
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int afpLock(sqlite3_file *id, int eFileLock){
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode = pFile->pInode;
+ afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
+
+ assert( pFile );
+ OSTRACE(("LOCK %d %s was %s(%s,%d) pid=%d (afp)\n", pFile->h,
+ azFileLock(eFileLock), azFileLock(pFile->eFileLock),
+ azFileLock(pInode->eFileLock), pInode->nShared , getpid()));
+
+ /* If there is already a lock of this type or more restrictive on the
+ ** unixFile, do nothing. Don't use the afp_end_lock: exit path, as
+ ** unixEnterMutex() hasn't been called yet.
+ */
+ if( pFile->eFileLock>=eFileLock ){
+ OSTRACE(("LOCK %d %s ok (already held) (afp)\n", pFile->h,
+ azFileLock(eFileLock)));
+ return SQLITE_OK;
+ }
+
+ /* Make sure the locking sequence is correct
+ ** (1) We never move from unlocked to anything higher than shared lock.
+ ** (2) SQLite never explicitly requests a pendig lock.
+ ** (3) A shared lock is always held when a reserve lock is requested.
+ */
+ assert( pFile->eFileLock!=NO_LOCK || eFileLock==SHARED_LOCK );
+ assert( eFileLock!=PENDING_LOCK );
+ assert( eFileLock!=RESERVED_LOCK || pFile->eFileLock==SHARED_LOCK );
+
+ /* This mutex is needed because pFile->pInode is shared across threads
+ */
+ unixEnterMutex();
+ pInode = pFile->pInode;
+
+ /* If some thread using this PID has a lock via a different unixFile*
+ ** handle that precludes the requested lock, return BUSY.
+ */
+ if( (pFile->eFileLock!=pInode->eFileLock &&
+ (pInode->eFileLock>=PENDING_LOCK || eFileLock>SHARED_LOCK))
+ ){
+ rc = SQLITE_BUSY;
+ goto afp_end_lock;
+ }
+
+ /* If a SHARED lock is requested, and some thread using this PID already
+ ** has a SHARED or RESERVED lock, then increment reference counts and
+ ** return SQLITE_OK.
+ */
+ if( eFileLock==SHARED_LOCK &&
+ (pInode->eFileLock==SHARED_LOCK || pInode->eFileLock==RESERVED_LOCK) ){
+ assert( eFileLock==SHARED_LOCK );
+ assert( pFile->eFileLock==0 );
+ assert( pInode->nShared>0 );
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nShared++;
+ pInode->nLock++;
+ goto afp_end_lock;
+ }
+
+ /* A PENDING lock is needed before acquiring a SHARED lock and before
+ ** acquiring an EXCLUSIVE lock. For the SHARED lock, the PENDING will
+ ** be released.
+ */
+ if( eFileLock==SHARED_LOCK
+ || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLockdbPath, pFile, PENDING_BYTE, 1, 1);
+ if (failed) {
+ rc = failed;
+ goto afp_end_lock;
+ }
+ }
+
+ /* If control gets to this point, then actually go ahead and make
+ ** operating system calls for the specified lock.
+ */
+ if( eFileLock==SHARED_LOCK ){
+ int lrc1, lrc2, lrc1Errno = 0;
+ long lk, mask;
+
+ assert( pInode->nShared==0 );
+ assert( pInode->eFileLock==0 );
+
+ mask = (sizeof(long)==8) ? LARGEST_INT64 : 0x7fffffff;
+ /* Now get the read-lock SHARED_LOCK */
+ /* note that the quality of the randomness doesn't matter that much */
+ lk = random();
+ pInode->sharedByte = (lk & mask)%(SHARED_SIZE - 1);
+ lrc1 = afpSetLock(context->dbPath, pFile,
+ SHARED_FIRST+pInode->sharedByte, 1, 1);
+ if( IS_LOCK_ERROR(lrc1) ){
+ lrc1Errno = pFile->lastErrno;
+ }
+ /* Drop the temporary PENDING lock */
+ lrc2 = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
+
+ if( IS_LOCK_ERROR(lrc1) ) {
+ pFile->lastErrno = lrc1Errno;
+ rc = lrc1;
+ goto afp_end_lock;
+ } else if( IS_LOCK_ERROR(lrc2) ){
+ rc = lrc2;
+ goto afp_end_lock;
+ } else if( lrc1 != SQLITE_OK ) {
+ rc = lrc1;
+ } else {
+ pFile->eFileLock = SHARED_LOCK;
+ pInode->nLock++;
+ pInode->nShared = 1;
+ }
+ }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
+ /* We are trying for an exclusive lock but another thread in this
+ ** same process is still holding a shared lock. */
+ rc = SQLITE_BUSY;
+ }else{
+ /* The request was for a RESERVED or EXCLUSIVE lock. It is
+ ** assumed that there is a SHARED or greater lock on the file
+ ** already.
+ */
+ int failed = 0;
+ assert( 0!=pFile->eFileLock );
+ if (eFileLock >= RESERVED_LOCK && pFile->eFileLock < RESERVED_LOCK) {
+ /* Acquire a RESERVED lock */
+ failed = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1,1);
+ if( !failed ){
+ context->reserved = 1;
+ }
+ }
+ if (!failed && eFileLock == EXCLUSIVE_LOCK) {
+ /* Acquire an EXCLUSIVE lock */
+
+ /* Remove the shared lock before trying the range. we'll need to
+ ** reestablish the shared lock if we can't get the afpUnlock
+ */
+ if( !(failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST +
+ pInode->sharedByte, 1, 0)) ){
+ int failed2 = SQLITE_OK;
+ /* now attemmpt to get the exclusive lock range */
+ failed = afpSetLock(context->dbPath, pFile, SHARED_FIRST,
+ SHARED_SIZE, 1);
+ if( failed && (failed2 = afpSetLock(context->dbPath, pFile,
+ SHARED_FIRST + pInode->sharedByte, 1, 1)) ){
+ /* Can't reestablish the shared lock. Sqlite can't deal, this is
+ ** a critical I/O error
+ */
+ rc = ((failed & SQLITE_IOERR) == SQLITE_IOERR) ? failed2 :
+ SQLITE_IOERR_LOCK;
+ goto afp_end_lock;
+ }
+ }else{
+ rc = failed;
+ }
+ }
+ if( failed ){
+ rc = failed;
+ }
+ }
+
+ if( rc==SQLITE_OK ){
+ pFile->eFileLock = eFileLock;
+ pInode->eFileLock = eFileLock;
+ }else if( eFileLock==EXCLUSIVE_LOCK ){
+ pFile->eFileLock = PENDING_LOCK;
+ pInode->eFileLock = PENDING_LOCK;
+ }
+
+afp_end_lock:
+ unixLeaveMutex();
+ OSTRACE(("LOCK %d %s %s (afp)\n", pFile->h, azFileLock(eFileLock),
+ rc==SQLITE_OK ? "ok" : "failed"));
+ return rc;
+}
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int afpUnlock(sqlite3_file *id, int eFileLock) {
+ int rc = SQLITE_OK;
+ unixFile *pFile = (unixFile*)id;
+ unixInodeInfo *pInode;
+ afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
+ int skipShared = 0;
+#ifdef SQLITE_TEST
+ int h = pFile->h;
+#endif
+
+ assert( pFile );
+ OSTRACE(("UNLOCK %d %d was %d(%d,%d) pid=%d (afp)\n", pFile->h, eFileLock,
+ pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
+ getpid()));
+
+ assert( eFileLock<=SHARED_LOCK );
+ if( pFile->eFileLock<=eFileLock ){
+ return SQLITE_OK;
+ }
+ unixEnterMutex();
+ pInode = pFile->pInode;
+ assert( pInode->nShared!=0 );
+ if( pFile->eFileLock>SHARED_LOCK ){
+ assert( pInode->eFileLock==pFile->eFileLock );
+ SimulateIOErrorBenign(1);
+ SimulateIOError( h=(-1) )
+ SimulateIOErrorBenign(0);
+
+#ifdef SQLITE_DEBUG
+ /* When reducing a lock such that other processes can start
+ ** reading the database file again, make sure that the
+ ** transaction counter was updated if any part of the database
+ ** file changed. If the transaction counter is not updated,
+ ** other connections to the same file might not realize that
+ ** the file has changed and hence might not know to flush their
+ ** cache. The use of a stale cache can lead to database corruption.
+ */
+ assert( pFile->inNormalWrite==0
+ || pFile->dbUpdate==0
+ || pFile->transCntrChng==1 );
+ pFile->inNormalWrite = 0;
+#endif
+
+ if( pFile->eFileLock==EXCLUSIVE_LOCK ){
+ rc = afpSetLock(context->dbPath, pFile, SHARED_FIRST, SHARED_SIZE, 0);
+ if( rc==SQLITE_OK && (eFileLock==SHARED_LOCK || pInode->nShared>1) ){
+ /* only re-establish the shared lock if necessary */
+ int sharedLockByte = SHARED_FIRST+pInode->sharedByte;
+ rc = afpSetLock(context->dbPath, pFile, sharedLockByte, 1, 1);
+ } else {
+ skipShared = 1;
+ }
+ }
+ if( rc==SQLITE_OK && pFile->eFileLock>=PENDING_LOCK ){
+ rc = afpSetLock(context->dbPath, pFile, PENDING_BYTE, 1, 0);
+ }
+ if( rc==SQLITE_OK && pFile->eFileLock>=RESERVED_LOCK && context->reserved ){
+ rc = afpSetLock(context->dbPath, pFile, RESERVED_BYTE, 1, 0);
+ if( !rc ){
+ context->reserved = 0;
+ }
+ }
+ if( rc==SQLITE_OK && (eFileLock==SHARED_LOCK || pInode->nShared>1)){
+ pInode->eFileLock = SHARED_LOCK;
+ }
+ }
+ if( rc==SQLITE_OK && eFileLock==NO_LOCK ){
+
+ /* Decrement the shared lock counter. Release the lock using an
+ ** OS call only when all threads in this same process have released
+ ** the lock.
+ */
+ unsigned long long sharedLockByte = SHARED_FIRST+pInode->sharedByte;
+ pInode->nShared--;
+ if( pInode->nShared==0 ){
+ SimulateIOErrorBenign(1);
+ SimulateIOError( h=(-1) )
+ SimulateIOErrorBenign(0);
+ if( !skipShared ){
+ rc = afpSetLock(context->dbPath, pFile, sharedLockByte, 1, 0);
+ }
+ if( !rc ){
+ pInode->eFileLock = NO_LOCK;
+ pFile->eFileLock = NO_LOCK;
+ }
+ }
+ if( rc==SQLITE_OK ){
+ pInode->nLock--;
+ assert( pInode->nLock>=0 );
+ if( pInode->nLock==0 ){
+ closePendingFds(pFile);
+ }
+ }
+ }
+
+ unixLeaveMutex();
+ if( rc==SQLITE_OK ) pFile->eFileLock = eFileLock;
+ return rc;
+}
+
+/*
+** Close a file & cleanup AFP specific locking context
+*/
+static int afpClose(sqlite3_file *id) {
+ int rc = SQLITE_OK;
+ if( id ){
+ unixFile *pFile = (unixFile*)id;
+ afpUnlock(id, NO_LOCK);
+ unixEnterMutex();
+ if( pFile->pInode && pFile->pInode->nLock ){
+ /* If there are outstanding locks, do not actually close the file just
+ ** yet because that would clear those locks. Instead, add the file
+ ** descriptor to pInode->aPending. It will be automatically closed when
+ ** the last lock is cleared.
+ */
+ setPendingFd(pFile);
+ }
+ releaseInodeInfo(pFile);
+ sqlite3_free(pFile->lockingContext);
+ rc = closeUnixFile(id);
+ unixLeaveMutex();
+ }
+ return rc;
+}
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+/*
+** The code above is the AFP lock implementation. The code is specific
+** to MacOSX and does not work on other unix platforms. No alternative
+** is available. If you don't compile for a mac, then the "unix-afp"
+** VFS is not available.
+**
+********************* End of the AFP lock implementation **********************
+******************************************************************************/
+
+/******************************************************************************
+*************************** Begin NFS Locking ********************************/
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+/*
+ ** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+ ** must be either NO_LOCK or SHARED_LOCK.
+ **
+ ** If the locking level of the file descriptor is already at or below
+ ** the requested locking level, this routine is a no-op.
+ */
+static int nfsUnlock(sqlite3_file *id, int eFileLock){
+ return posixUnlock(id, eFileLock, 1);
+}
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+/*
+** The code above is the NFS lock implementation. The code is specific
+** to MacOSX and does not work on other unix platforms. No alternative
+** is available.
+**
+********************* End of the NFS lock implementation **********************
+******************************************************************************/
+
+/******************************************************************************
+**************** Non-locking sqlite3_file methods *****************************
+**
+** The next division contains implementations for all methods of the
+** sqlite3_file object other than the locking methods. The locking
+** methods were defined in divisions above (one locking method per
+** division). Those methods that are common to all locking modes
+** are gather together into this division.
+*/
+
+/*
+** Seek to the offset passed as the second argument, then read cnt
+** bytes into pBuf. Return the number of bytes actually read.
+**
+** NB: If you define USE_PREAD or USE_PREAD64, then it might also
+** be necessary to define _XOPEN_SOURCE to be 500. This varies from
+** one system to another. Since SQLite does not define USE_PREAD
+** any any form by default, we will not attempt to define _XOPEN_SOURCE.
+** See tickets #2741 and #2681.
+**
+** To avoid stomping the errno value on a failed read the lastErrno value
+** is set before returning.
+*/
+static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
+ int got;
+ int prior = 0;
+#if (!defined(USE_PREAD) && !defined(USE_PREAD64))
+ i64 newOffset;
+#endif
+ TIMER_START;
+ assert( cnt==(cnt&0x1ffff) );
+ assert( id->h>2 );
+ cnt &= 0x1ffff;
+ do{
+#if defined(USE_PREAD)
+ got = osPread(id->h, pBuf, cnt, offset);
+ SimulateIOError( got = -1 );
+#elif defined(USE_PREAD64)
+ got = osPread64(id->h, pBuf, cnt, offset);
+ SimulateIOError( got = -1 );
+#else
+ newOffset = lseek(id->h, offset, SEEK_SET);
+ SimulateIOError( newOffset-- );
+ if( newOffset!=offset ){
+ if( newOffset == -1 ){
+ ((unixFile*)id)->lastErrno = errno;
+ }else{
+ ((unixFile*)id)->lastErrno = 0;
+ }
+ return -1;
+ }
+ got = osRead(id->h, pBuf, cnt);
+#endif
+ if( got==cnt ) break;
+ if( got<0 ){
+ if( errno==EINTR ){ got = 1; continue; }
+ prior = 0;
+ ((unixFile*)id)->lastErrno = errno;
+ break;
+ }else if( got>0 ){
+ cnt -= got;
+ offset += got;
+ prior += got;
+ pBuf = (void*)(got + (char*)pBuf);
+ }
+ }while( got>0 );
+ TIMER_END;
+ OSTRACE(("READ %-3d %5d %7lld %llu\n",
+ id->h, got+prior, offset-prior, TIMER_ELAPSED));
+ return got+prior;
+}
+
+/*
+** Read data from a file into a buffer. Return SQLITE_OK if all
+** bytes were read successfully and SQLITE_IOERR if anything goes
+** wrong.
+*/
+static int unixRead(
+ sqlite3_file *id,
+ void *pBuf,
+ int amt,
+ sqlite3_int64 offset
+){
+ unixFile *pFile = (unixFile *)id;
+ int got;
+ assert( id );
+ assert( offset>=0 );
+ assert( amt>0 );
+
+ /* If this is a database file (not a journal, master-journal or temp
+ ** file), the bytes in the locking range should never be read or written. */
+#if 0
+ assert( pFile->pUnused==0
+ || offset>=PENDING_BYTE+512
+ || offset+amt<=PENDING_BYTE
+ );
+#endif
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this read request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
+ return SQLITE_OK;
+ }else{
+ int nCopy = pFile->mmapSize - offset;
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+ got = seekAndRead(pFile, offset, pBuf, amt);
+ if( got==amt ){
+ return SQLITE_OK;
+ }else if( got<0 ){
+ /* lastErrno set by seekAndRead */
+ return SQLITE_IOERR_READ;
+ }else{
+ pFile->lastErrno = 0; /* not a system error */
+ /* Unread parts of the buffer must be zero-filled */
+ memset(&((char*)pBuf)[got], 0, amt-got);
+ return SQLITE_IOERR_SHORT_READ;
+ }
+}
+
+/*
+** Attempt to seek the file-descriptor passed as the first argument to
+** absolute offset iOff, then attempt to write nBuf bytes of data from
+** pBuf to it. If an error occurs, return -1 and set *piErrno. Otherwise,
+** return the actual number of bytes written (which may be less than
+** nBuf).
+*/
+static int seekAndWriteFd(
+ int fd, /* File descriptor to write to */
+ i64 iOff, /* File offset to begin writing at */
+ const void *pBuf, /* Copy data from this buffer to the file */
+ int nBuf, /* Size of buffer pBuf in bytes */
+ int *piErrno /* OUT: Error number if error occurs */
+){
+ int rc = 0; /* Value returned by system call */
+
+ assert( nBuf==(nBuf&0x1ffff) );
+ assert( fd>2 );
+ nBuf &= 0x1ffff;
+ TIMER_START;
+
+#if defined(USE_PREAD)
+ do{ rc = osPwrite(fd, pBuf, nBuf, iOff); }while( rc<0 && errno==EINTR );
+#elif defined(USE_PREAD64)
+ do{ rc = osPwrite64(fd, pBuf, nBuf, iOff);}while( rc<0 && errno==EINTR);
+#else
+ do{
+ i64 iSeek = lseek(fd, iOff, SEEK_SET);
+ SimulateIOError( iSeek-- );
+
+ if( iSeek!=iOff ){
+ if( piErrno ) *piErrno = (iSeek==-1 ? errno : 0);
+ return -1;
+ }
+ rc = osWrite(fd, pBuf, nBuf);
+ }while( rc<0 && errno==EINTR );
+#endif
+
+ TIMER_END;
+ OSTRACE(("WRITE %-3d %5d %7lld %llu\n", fd, rc, iOff, TIMER_ELAPSED));
+
+ if( rc<0 && piErrno ) *piErrno = errno;
+ return rc;
+}
+
+
+/*
+** Seek to the offset in id->offset then read cnt bytes into pBuf.
+** Return the number of bytes actually read. Update the offset.
+**
+** To avoid stomping the errno value on a failed write the lastErrno value
+** is set before returning.
+*/
+static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
+ return seekAndWriteFd(id->h, offset, pBuf, cnt, &id->lastErrno);
+}
+
+
+/*
+** Write data from a buffer into a file. Return SQLITE_OK on success
+** or some other error code on failure.
+*/
+static int unixWrite(
+ sqlite3_file *id,
+ const void *pBuf,
+ int amt,
+ sqlite3_int64 offset
+){
+ unixFile *pFile = (unixFile*)id;
+ int wrote = 0;
+ assert( id );
+ assert( amt>0 );
+
+ /* If this is a database file (not a journal, master-journal or temp
+ ** file), the bytes in the locking range should never be read or written. */
+#if 0
+ assert( pFile->pUnused==0
+ || offset>=PENDING_BYTE+512
+ || offset+amt<=PENDING_BYTE
+ );
+#endif
+
+#ifdef SQLITE_DEBUG
+ /* If we are doing a normal write to a database file (as opposed to
+ ** doing a hot-journal rollback or a write to some file other than a
+ ** normal database file) then record the fact that the database
+ ** has changed. If the transaction counter is modified, record that
+ ** fact too.
+ */
+ if( pFile->inNormalWrite ){
+ pFile->dbUpdate = 1; /* The database has been modified */
+ if( offset<=24 && offset+amt>=27 ){
+ int rc;
+ char oldCntr[4];
+ SimulateIOErrorBenign(1);
+ rc = seekAndRead(pFile, 24, oldCntr, 4);
+ SimulateIOErrorBenign(0);
+ if( rc!=4 || memcmp(oldCntr, &((char*)pBuf)[24-offset], 4)!=0 ){
+ pFile->transCntrChng = 1; /* The transaction counter has changed */
+ }
+ }
+ }
+#endif
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this write request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
+ return SQLITE_OK;
+ }else{
+ int nCopy = pFile->mmapSize - offset;
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+ while( amt>0 && (wrote = seekAndWrite(pFile, offset, pBuf, amt))>0 ){
+ amt -= wrote;
+ offset += wrote;
+ pBuf = &((char*)pBuf)[wrote];
+ }
+ SimulateIOError(( wrote=(-1), amt=1 ));
+ SimulateDiskfullError(( wrote=0, amt=1 ));
+
+ if( amt>0 ){
+ if( wrote<0 && pFile->lastErrno!=ENOSPC ){
+ /* lastErrno set by seekAndWrite */
+ return SQLITE_IOERR_WRITE;
+ }else{
+ pFile->lastErrno = 0; /* not a system error */
+ return SQLITE_FULL;
+ }
+ }
+
+ return SQLITE_OK;
+}
+
+#ifdef SQLITE_TEST
+/*
+** Count the number of fullsyncs and normal syncs. This is used to test
+** that syncs and fullsyncs are occurring at the right times.
+*/
+SQLITE_API int sqlite3_sync_count = 0;
+SQLITE_API int sqlite3_fullsync_count = 0;
+#endif
+
+/*
+** We do not trust systems to provide a working fdatasync(). Some do.
+** Others do no. To be safe, we will stick with the (slightly slower)
+** fsync(). If you know that your system does support fdatasync() correctly,
+** then simply compile with -Dfdatasync=fdatasync
+*/
+#if !defined(fdatasync)
+# define fdatasync fsync
+#endif
+
+/*
+** Define HAVE_FULLFSYNC to 0 or 1 depending on whether or not
+** the F_FULLFSYNC macro is defined. F_FULLFSYNC is currently
+** only available on Mac OS X. But that could change.
+*/
+#ifdef F_FULLFSYNC
+# define HAVE_FULLFSYNC 1
+#else
+# define HAVE_FULLFSYNC 0
+#endif
+
+
+/*
+** The fsync() system call does not work as advertised on many
+** unix systems. The following procedure is an attempt to make
+** it work better.
+**
+** The SQLITE_NO_SYNC macro disables all fsync()s. This is useful
+** for testing when we want to run through the test suite quickly.
+** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
+** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
+** or power failure will likely corrupt the database file.
+**
+** SQLite sets the dataOnly flag if the size of the file is unchanged.
+** The idea behind dataOnly is that it should only write the file content
+** to disk, not the inode. We only set dataOnly if the file size is
+** unchanged since the file size is part of the inode. However,
+** Ted Ts'o tells us that fdatasync() will also write the inode if the
+** file size has changed. The only real difference between fdatasync()
+** and fsync(), Ted tells us, is that fdatasync() will not flush the
+** inode if the mtime or owner or other inode attributes have changed.
+** We only care about the file size, not the other file attributes, so
+** as far as SQLite is concerned, an fdatasync() is always adequate.
+** So, we always use fdatasync() if it is available, regardless of
+** the value of the dataOnly flag.
+*/
+static int full_fsync(int fd, int fullSync, int dataOnly){
+ int rc;
+
+ /* The following "ifdef/elif/else/" block has the same structure as
+ ** the one below. It is replicated here solely to avoid cluttering
+ ** up the real code with the UNUSED_PARAMETER() macros.
+ */
+#ifdef SQLITE_NO_SYNC
+ UNUSED_PARAMETER(fd);
+ UNUSED_PARAMETER(fullSync);
+ UNUSED_PARAMETER(dataOnly);
+#elif HAVE_FULLFSYNC
+ UNUSED_PARAMETER(dataOnly);
+#else
+ UNUSED_PARAMETER(fullSync);
+ UNUSED_PARAMETER(dataOnly);
+#endif
+
+ /* Record the number of times that we do a normal fsync() and
+ ** FULLSYNC. This is used during testing to verify that this procedure
+ ** gets called with the correct arguments.
+ */
+#ifdef SQLITE_TEST
+ if( fullSync ) sqlite3_fullsync_count++;
+ sqlite3_sync_count++;
+#endif
+
+ /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
+ ** no-op
+ */
+#ifdef SQLITE_NO_SYNC
+ rc = SQLITE_OK;
+#elif HAVE_FULLFSYNC
+ if( fullSync ){
+ rc = osFcntl(fd, F_FULLFSYNC, 0);
+ }else{
+ rc = 1;
+ }
+ /* If the FULLFSYNC failed, fall back to attempting an fsync().
+ ** It shouldn't be possible for fullfsync to fail on the local
+ ** file system (on OSX), so failure indicates that FULLFSYNC
+ ** isn't supported for this file system. So, attempt an fsync
+ ** and (for now) ignore the overhead of a superfluous fcntl call.
+ ** It'd be better to detect fullfsync support once and avoid
+ ** the fcntl call every time sync is called.
+ */
+ if( rc ) rc = fsync(fd);
+
+#elif defined(__APPLE__)
+ /* fdatasync() on HFS+ doesn't yet flush the file size if it changed correctly
+ ** so currently we default to the macro that redefines fdatasync to fsync
+ */
+ rc = fsync(fd);
+#else
+ rc = fdatasync(fd);
+#if OS_VXWORKS
+ if( rc==-1 && errno==ENOTSUP ){
+ rc = fsync(fd);
+ }
+#endif /* OS_VXWORKS */
+#endif /* ifdef SQLITE_NO_SYNC elif HAVE_FULLFSYNC */
+
+ if( OS_VXWORKS && rc!= -1 ){
+ rc = 0;
+ }
+ return rc;
+}
+
+/*
+** Open a file descriptor to the directory containing file zFilename.
+** If successful, *pFd is set to the opened file descriptor and
+** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
+** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
+** value.
+**
+** The directory file descriptor is used for only one thing - to
+** fsync() a directory to make sure file creation and deletion events
+** are flushed to disk. Such fsyncs are not needed on newer
+** journaling filesystems, but are required on older filesystems.
+**
+** This routine can be overridden using the xSetSysCall interface.
+** The ability to override this routine was added in support of the
+** chromium sandbox. Opening a directory is a security risk (we are
+** told) so making it overrideable allows the chromium sandbox to
+** replace this routine with a harmless no-op. To make this routine
+** a no-op, replace it with a stub that returns SQLITE_OK but leaves
+** *pFd set to a negative number.
+**
+** If SQLITE_OK is returned, the caller is responsible for closing
+** the file descriptor *pFd using close().
+*/
+static int openDirectory(const char *zFilename, int *pFd){
+ int ii;
+ int fd = -1;
+ char zDirname[MAX_PATHNAME+1];
+
+ sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename);
+ for(ii=(int)strlen(zDirname); ii>1 && zDirname[ii]!='/'; ii--);
+ if( ii>0 ){
+ zDirname[ii] = '\0';
+ fd = robust_open(zDirname, O_RDONLY|O_BINARY, 0);
+ if( fd>=0 ){
+ OSTRACE(("OPENDIR %-3d %s\n", fd, zDirname));
+ }
+ }
+ *pFd = fd;
+ return (fd>=0?SQLITE_OK:unixLogError(SQLITE_CANTOPEN_BKPT, "open", zDirname));
+}
+
+/*
+** Make sure all writes to a particular file are committed to disk.
+**
+** If dataOnly==0 then both the file itself and its metadata (file
+** size, access time, etc) are synced. If dataOnly!=0 then only the
+** file data is synced.
+**
+** Under Unix, also make sure that the directory entry for the file
+** has been created by fsync-ing the directory that contains the file.
+** If we do not do this and we encounter a power failure, the directory
+** entry for the journal might not exist after we reboot. The next
+** SQLite to access the file will not know that the journal exists (because
+** the directory entry for the journal was never created) and the transaction
+** will not roll back - possibly leading to database corruption.
+*/
+static int unixSync(sqlite3_file *id, int flags){
+ int rc;
+ unixFile *pFile = (unixFile*)id;
+
+ int isDataOnly = (flags&SQLITE_SYNC_DATAONLY);
+ int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL;
+
+ /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
+ assert((flags&0x0F)==SQLITE_SYNC_NORMAL
+ || (flags&0x0F)==SQLITE_SYNC_FULL
+ );
+
+ /* Unix cannot, but some systems may return SQLITE_FULL from here. This
+ ** line is to test that doing so does not cause any problems.
+ */
+ SimulateDiskfullError( return SQLITE_FULL );
+
+ assert( pFile );
+ OSTRACE(("SYNC %-3d\n", pFile->h));
+ rc = full_fsync(pFile->h, isFullsync, isDataOnly);
+ SimulateIOError( rc=1 );
+ if( rc ){
+ pFile->lastErrno = errno;
+ return unixLogError(SQLITE_IOERR_FSYNC, "full_fsync", pFile->zPath);
+ }
+
+ /* Also fsync the directory containing the file if the DIRSYNC flag
+ ** is set. This is a one-time occurrence. Many systems (examples: AIX)
+ ** are unable to fsync a directory, so ignore errors on the fsync.
+ */
+ if( pFile->ctrlFlags & UNIXFILE_DIRSYNC ){
+ int dirfd;
+ OSTRACE(("DIRSYNC %s (have_fullfsync=%d fullsync=%d)\n", pFile->zPath,
+ HAVE_FULLFSYNC, isFullsync));
+ rc = osOpenDirectory(pFile->zPath, &dirfd);
+ if( rc==SQLITE_OK && dirfd>=0 ){
+ full_fsync(dirfd, 0, 0);
+ robust_close(pFile, dirfd, __LINE__);
+ }else if( rc==SQLITE_CANTOPEN ){
+ rc = SQLITE_OK;
+ }
+ pFile->ctrlFlags &= ~UNIXFILE_DIRSYNC;
+ }
+ return rc;
+}
+
+/*
+** Truncate an open file to a specified size
+*/
+static int unixTruncate(sqlite3_file *id, i64 nByte){
+ unixFile *pFile = (unixFile *)id;
+ int rc;
+ assert( pFile );
+ SimulateIOError( return SQLITE_IOERR_TRUNCATE );
+
+ /* If the user has configured a chunk-size for this file, truncate the
+ ** file so that it consists of an integer number of chunks (i.e. the
+ ** actual file size after the operation may be larger than the requested
+ ** size).
+ */
+ if( pFile->szChunk>0 ){
+ nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+ }
+
+ rc = robust_ftruncate(pFile->h, (off_t)nByte);
+ if( rc ){
+ pFile->lastErrno = errno;
+ return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
+ }else{
+#ifdef SQLITE_DEBUG
+ /* If we are doing a normal write to a database file (as opposed to
+ ** doing a hot-journal rollback or a write to some file other than a
+ ** normal database file) and we truncate the file to zero length,
+ ** that effectively updates the change counter. This might happen
+ ** when restoring a database using the backup API from a zero-length
+ ** source.
+ */
+ if( pFile->inNormalWrite && nByte==0 ){
+ pFile->transCntrChng = 1;
+ }
+#endif
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* If the file was just truncated to a size smaller than the currently
+ ** mapped region, reduce the effective mapping size as well. SQLite will
+ ** use read() and write() to access data beyond this point from now on.
+ */
+ if( nBytemmapSize ){
+ pFile->mmapSize = nByte;
+ }
+#endif
+
+ return SQLITE_OK;
+ }
+}
+
+/*
+** Determine the current size of a file in bytes
+*/
+static int unixFileSize(sqlite3_file *id, i64 *pSize){
+ int rc;
+ struct stat buf;
+ assert( id );
+ rc = osFstat(((unixFile*)id)->h, &buf);
+ SimulateIOError( rc=1 );
+ if( rc!=0 ){
+ ((unixFile*)id)->lastErrno = errno;
+ return SQLITE_IOERR_FSTAT;
+ }
+ *pSize = buf.st_size;
+
+ /* When opening a zero-size database, the findInodeInfo() procedure
+ ** writes a single byte into that file in order to work around a bug
+ ** in the OS-X msdos filesystem. In order to avoid problems with upper
+ ** layers, we need to report this file size as zero even though it is
+ ** really 1. Ticket #3260.
+ */
+ if( *pSize==1 ) *pSize = 0;
+
+
+ return SQLITE_OK;
+}
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+/*
+** Handler for proxy-locking file-control verbs. Defined below in the
+** proxying locking division.
+*/
+static int proxyFileControl(sqlite3_file*,int,void*);
+#endif
+
+/*
+** This function is called to handle the SQLITE_FCNTL_SIZE_HINT
+** file-control operation. Enlarge the database to nBytes in size
+** (rounded up to the next chunk-size). If the database is already
+** nBytes or larger, this routine is a no-op.
+*/
+static int fcntlSizeHint(unixFile *pFile, i64 nByte){
+ if( pFile->szChunk>0 ){
+ i64 nSize; /* Required file size */
+ struct stat buf; /* Used to hold return values of fstat() */
+
+ if( osFstat(pFile->h, &buf) ) return SQLITE_IOERR_FSTAT;
+
+ nSize = ((nByte+pFile->szChunk-1) / pFile->szChunk) * pFile->szChunk;
+ if( nSize>(i64)buf.st_size ){
+
+#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
+ /* The code below is handling the return value of osFallocate()
+ ** correctly. posix_fallocate() is defined to "returns zero on success,
+ ** or an error number on failure". See the manpage for details. */
+ int err;
+ do{
+ err = osFallocate(pFile->h, buf.st_size, nSize-buf.st_size);
+ }while( err==EINTR );
+ if( err ) return SQLITE_IOERR_WRITE;
+#else
+ /* If the OS does not have posix_fallocate(), fake it. First use
+ ** ftruncate() to set the file size, then write a single byte to
+ ** the last byte in each block within the extended region. This
+ ** is the same technique used by glibc to implement posix_fallocate()
+ ** on systems that do not have a real fallocate() system call.
+ */
+ int nBlk = buf.st_blksize; /* File-system block size */
+ i64 iWrite; /* Next offset to write to */
+
+ if( robust_ftruncate(pFile->h, nSize) ){
+ pFile->lastErrno = errno;
+ return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
+ }
+ iWrite = ((buf.st_size + 2*nBlk - 1)/nBlk)*nBlk-1;
+ while( iWrite0
+ if( pFile->mmapSizeMax>0 && nByte>pFile->mmapSize ){
+ int rc;
+ if( pFile->szChunk<=0 ){
+ if( robust_ftruncate(pFile->h, nByte) ){
+ pFile->lastErrno = errno;
+ return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
+ }
+ }
+
+ rc = unixMapfile(pFile, nByte);
+ return rc;
+ }
+#endif
+
+ return SQLITE_OK;
+}
+
+/*
+** If *pArg is inititially negative then this is a query. Set *pArg to
+** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
+**
+** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
+*/
+static void unixModeBit(unixFile *pFile, unsigned char mask, int *pArg){
+ if( *pArg<0 ){
+ *pArg = (pFile->ctrlFlags & mask)!=0;
+ }else if( (*pArg)==0 ){
+ pFile->ctrlFlags &= ~mask;
+ }else{
+ pFile->ctrlFlags |= mask;
+ }
+}
+
+/* Forward declaration */
+static int unixGetTempname(int nBuf, char *zBuf);
+
+/*
+** Information and control of an open file handle.
+*/
+static int unixFileControl(sqlite3_file *id, int op, void *pArg){
+ unixFile *pFile = (unixFile*)id;
+ switch( op ){
+ case SQLITE_FCNTL_LOCKSTATE: {
+ *(int*)pArg = pFile->eFileLock;
+ return SQLITE_OK;
+ }
+ case SQLITE_LAST_ERRNO: {
+ *(int*)pArg = pFile->lastErrno;
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_CHUNK_SIZE: {
+ pFile->szChunk = *(int *)pArg;
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_SIZE_HINT: {
+ int rc;
+ SimulateIOErrorBenign(1);
+ rc = fcntlSizeHint(pFile, *(i64 *)pArg);
+ SimulateIOErrorBenign(0);
+ return rc;
+ }
+ case SQLITE_FCNTL_PERSIST_WAL: {
+ unixModeBit(pFile, UNIXFILE_PERSIST_WAL, (int*)pArg);
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
+ unixModeBit(pFile, UNIXFILE_PSOW, (int*)pArg);
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_VFSNAME: {
+ *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_TEMPFILENAME: {
+ char *zTFile = sqlite3_malloc( pFile->pVfs->mxPathname );
+ if( zTFile ){
+ unixGetTempname(pFile->pVfs->mxPathname, zTFile);
+ *(char**)pArg = zTFile;
+ }
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_HAS_MOVED: {
+ *(int*)pArg = fileHasMoved(pFile);
+ return SQLITE_OK;
+ }
+#if SQLITE_MAX_MMAP_SIZE>0
+ case SQLITE_FCNTL_MMAP_SIZE: {
+ i64 newLimit = *(i64*)pArg;
+ int rc = SQLITE_OK;
+ if( newLimit>sqlite3GlobalConfig.mxMmap ){
+ newLimit = sqlite3GlobalConfig.mxMmap;
+ }
+ *(i64*)pArg = pFile->mmapSizeMax;
+ if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
+ pFile->mmapSizeMax = newLimit;
+ if( pFile->mmapSize>0 ){
+ unixUnmapfile(pFile);
+ rc = unixMapfile(pFile, -1);
+ }
+ }
+ return rc;
+ }
+#endif
+#ifdef SQLITE_DEBUG
+ /* The pager calls this method to signal that it has done
+ ** a rollback and that the database is therefore unchanged and
+ ** it hence it is OK for the transaction change counter to be
+ ** unchanged.
+ */
+ case SQLITE_FCNTL_DB_UNCHANGED: {
+ ((unixFile*)id)->dbUpdate = 0;
+ return SQLITE_OK;
+ }
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+ case SQLITE_SET_LOCKPROXYFILE:
+ case SQLITE_GET_LOCKPROXYFILE: {
+ return proxyFileControl(id,op,pArg);
+ }
+#endif /* SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__) */
+ }
+ return SQLITE_NOTFOUND;
+}
+
+/*
+** Return the sector size in bytes of the underlying block device for
+** the specified file. This is almost always 512 bytes, but may be
+** larger for some devices.
+**
+** SQLite code assumes this function cannot fail. It also assumes that
+** if two files are created in the same file-system directory (i.e.
+** a database and its journal file) that the sector size will be the
+** same for both.
+*/
+#ifndef __QNXNTO__
+static int unixSectorSize(sqlite3_file *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ return SQLITE_DEFAULT_SECTOR_SIZE;
+}
+#endif
+
+/*
+** The following version of unixSectorSize() is optimized for QNX.
+*/
+#ifdef __QNXNTO__
+#include
+#include
+static int unixSectorSize(sqlite3_file *id){
+ unixFile *pFile = (unixFile*)id;
+ if( pFile->sectorSize == 0 ){
+ struct statvfs fsInfo;
+
+ /* Set defaults for non-supported filesystems */
+ pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
+ pFile->deviceCharacteristics = 0;
+ if( fstatvfs(pFile->h, &fsInfo) == -1 ) {
+ return pFile->sectorSize;
+ }
+
+ if( !strcmp(fsInfo.f_basetype, "tmp") ) {
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ SQLITE_IOCAP_ATOMIC4K | /* All ram filesystem writes are atomic */
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( strstr(fsInfo.f_basetype, "etfs") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ /* etfs cluster size writes are atomic */
+ (pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) |
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( !strcmp(fsInfo.f_basetype, "qnx6") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ SQLITE_IOCAP_ATOMIC | /* All filesystem writes are atomic */
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( !strcmp(fsInfo.f_basetype, "qnx4") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ /* full bitset of atomics from max sector size and smaller */
+ ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else if( strstr(fsInfo.f_basetype, "dos") ){
+ pFile->sectorSize = fsInfo.f_bsize;
+ pFile->deviceCharacteristics =
+ /* full bitset of atomics from max sector size and smaller */
+ ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
+ SQLITE_IOCAP_SEQUENTIAL | /* The ram filesystem has no write behind
+ ** so it is ordered */
+ 0;
+ }else{
+ pFile->deviceCharacteristics =
+ SQLITE_IOCAP_ATOMIC512 | /* blocks are atomic */
+ SQLITE_IOCAP_SAFE_APPEND | /* growing the file does not occur until
+ ** the write succeeds */
+ 0;
+ }
+ }
+ /* Last chance verification. If the sector size isn't a multiple of 512
+ ** then it isn't valid.*/
+ if( pFile->sectorSize % 512 != 0 ){
+ pFile->deviceCharacteristics = 0;
+ pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
+ }
+ return pFile->sectorSize;
+}
+#endif /* __QNXNTO__ */
+
+/*
+** Return the device characteristics for the file.
+**
+** This VFS is set up to return SQLITE_IOCAP_POWERSAFE_OVERWRITE by default.
+** However, that choice is contraversial since technically the underlying
+** file system does not always provide powersafe overwrites. (In other
+** words, after a power-loss event, parts of the file that were never
+** written might end up being altered.) However, non-PSOW behavior is very,
+** very rare. And asserting PSOW makes a large reduction in the amount
+** of required I/O for journaling, since a lot of padding is eliminated.
+** Hence, while POWERSAFE_OVERWRITE is on by default, there is a file-control
+** available to turn it off and URI query parameter available to turn it off.
+*/
+static int unixDeviceCharacteristics(sqlite3_file *id){
+ unixFile *p = (unixFile*)id;
+ int rc = 0;
+#ifdef __QNXNTO__
+ if( p->sectorSize==0 ) unixSectorSize(id);
+ rc = p->deviceCharacteristics;
+#endif
+ if( p->ctrlFlags & UNIXFILE_PSOW ){
+ rc |= SQLITE_IOCAP_POWERSAFE_OVERWRITE;
+ }
+ return rc;
+}
+
+#ifndef SQLITE_OMIT_WAL
+
+
+/*
+** Object used to represent an shared memory buffer.
+**
+** When multiple threads all reference the same wal-index, each thread
+** has its own unixShm object, but they all point to a single instance
+** of this unixShmNode object. In other words, each wal-index is opened
+** only once per process.
+**
+** Each unixShmNode object is connected to a single unixInodeInfo object.
+** We could coalesce this object into unixInodeInfo, but that would mean
+** every open file that does not use shared memory (in other words, most
+** open files) would have to carry around this extra information. So
+** the unixInodeInfo object contains a pointer to this unixShmNode object
+** and the unixShmNode object is created only when needed.
+**
+** unixMutexHeld() must be true when creating or destroying
+** this object or while reading or writing the following fields:
+**
+** nRef
+**
+** The following fields are read-only after the object is created:
+**
+** fid
+** zFilename
+**
+** Either unixShmNode.mutex must be held or unixShmNode.nRef==0 and
+** unixMutexHeld() is true when reading or writing any other field
+** in this structure.
+*/
+struct unixShmNode {
+ unixInodeInfo *pInode; /* unixInodeInfo that owns this SHM node */
+ sqlite3_mutex *mutex; /* Mutex to access this object */
+ char *zFilename; /* Name of the mmapped file */
+ int h; /* Open file descriptor */
+ int szRegion; /* Size of shared-memory regions */
+ u16 nRegion; /* Size of array apRegion */
+ u8 isReadonly; /* True if read-only */
+ char **apRegion; /* Array of mapped shared-memory regions */
+ int nRef; /* Number of unixShm objects pointing to this */
+ unixShm *pFirst; /* All unixShm objects pointing to this */
+#ifdef SQLITE_DEBUG
+ u8 exclMask; /* Mask of exclusive locks held */
+ u8 sharedMask; /* Mask of shared locks held */
+ u8 nextShmId; /* Next available unixShm.id value */
+#endif
+};
+
+/*
+** Structure used internally by this VFS to record the state of an
+** open shared memory connection.
+**
+** The following fields are initialized when this object is created and
+** are read-only thereafter:
+**
+** unixShm.pFile
+** unixShm.id
+**
+** All other fields are read/write. The unixShm.pFile->mutex must be held
+** while accessing any read/write fields.
+*/
+struct unixShm {
+ unixShmNode *pShmNode; /* The underlying unixShmNode object */
+ unixShm *pNext; /* Next unixShm with the same unixShmNode */
+ u8 hasMutex; /* True if holding the unixShmNode mutex */
+ u8 id; /* Id of this connection within its unixShmNode */
+ u16 sharedMask; /* Mask of shared locks held */
+ u16 exclMask; /* Mask of exclusive locks held */
+};
+
+/*
+** Constants used for locking
+*/
+#define UNIX_SHM_BASE ((22+SQLITE_SHM_NLOCK)*4) /* first lock byte */
+#define UNIX_SHM_DMS (UNIX_SHM_BASE+SQLITE_SHM_NLOCK) /* deadman switch */
+
+/*
+** Apply posix advisory locks for all bytes from ofst through ofst+n-1.
+**
+** Locks block if the mask is exactly UNIX_SHM_C and are non-blocking
+** otherwise.
+*/
+static int unixShmSystemLock(
+ unixShmNode *pShmNode, /* Apply locks to this open shared-memory segment */
+ int lockType, /* F_UNLCK, F_RDLCK, or F_WRLCK */
+ int ofst, /* First byte of the locking range */
+ int n /* Number of bytes to lock */
+){
+ struct flock f; /* The posix advisory locking structure */
+ int rc = SQLITE_OK; /* Result code form fcntl() */
+
+ /* Access to the unixShmNode object is serialized by the caller */
+ assert( sqlite3_mutex_held(pShmNode->mutex) || pShmNode->nRef==0 );
+
+ /* Shared locks never span more than one byte */
+ assert( n==1 || lockType!=F_RDLCK );
+
+ /* Locks are within range */
+ assert( n>=1 && nh>=0 ){
+ /* Initialize the locking parameters */
+ memset(&f, 0, sizeof(f));
+ f.l_type = lockType;
+ f.l_whence = SEEK_SET;
+ f.l_start = ofst;
+ f.l_len = n;
+
+ rc = osFcntl(pShmNode->h, F_SETLK, &f);
+ rc = (rc!=(-1)) ? SQLITE_OK : SQLITE_BUSY;
+ }
+
+ /* Update the global lock state and do debug tracing */
+#ifdef SQLITE_DEBUG
+ { u16 mask;
+ OSTRACE(("SHM-LOCK "));
+ mask = ofst>31 ? 0xffff : (1<<(ofst+n)) - (1<exclMask &= ~mask;
+ pShmNode->sharedMask &= ~mask;
+ }else if( lockType==F_RDLCK ){
+ OSTRACE(("read-lock %d ok", ofst));
+ pShmNode->exclMask &= ~mask;
+ pShmNode->sharedMask |= mask;
+ }else{
+ assert( lockType==F_WRLCK );
+ OSTRACE(("write-lock %d ok", ofst));
+ pShmNode->exclMask |= mask;
+ pShmNode->sharedMask &= ~mask;
+ }
+ }else{
+ if( lockType==F_UNLCK ){
+ OSTRACE(("unlock %d failed", ofst));
+ }else if( lockType==F_RDLCK ){
+ OSTRACE(("read-lock failed"));
+ }else{
+ assert( lockType==F_WRLCK );
+ OSTRACE(("write-lock %d failed", ofst));
+ }
+ }
+ OSTRACE((" - afterwards %03x,%03x\n",
+ pShmNode->sharedMask, pShmNode->exclMask));
+ }
+#endif
+
+ return rc;
+}
+
+/*
+** Return the system page size.
+**
+** This function should not be called directly by other code in this file.
+** Instead, it should be called via macro osGetpagesize().
+*/
+static int unixGetpagesize(void){
+#if defined(_BSD_SOURCE)
+ return getpagesize();
+#else
+ return (int)sysconf(_SC_PAGESIZE);
+#endif
+}
+
+/*
+** Return the minimum number of 32KB shm regions that should be mapped at
+** a time, assuming that each mapping must be an integer multiple of the
+** current system page-size.
+**
+** Usually, this is 1. The exception seems to be systems that are configured
+** to use 64KB pages - in this case each mapping must cover at least two
+** shm regions.
+*/
+static int unixShmRegionPerMap(void){
+ int shmsz = 32*1024; /* SHM region size */
+ int pgsz = osGetpagesize(); /* System page size */
+ assert( ((pgsz-1)&pgsz)==0 ); /* Page size must be a power of 2 */
+ if( pgszpInode->pShmNode;
+ assert( unixMutexHeld() );
+ if( p && p->nRef==0 ){
+ int nShmPerMap = unixShmRegionPerMap();
+ int i;
+ assert( p->pInode==pFd->pInode );
+ sqlite3_mutex_free(p->mutex);
+ for(i=0; inRegion; i+=nShmPerMap){
+ if( p->h>=0 ){
+ osMunmap(p->apRegion[i], p->szRegion);
+ }else{
+ sqlite3_free(p->apRegion[i]);
+ }
+ }
+ sqlite3_free(p->apRegion);
+ if( p->h>=0 ){
+ robust_close(pFd, p->h, __LINE__);
+ p->h = -1;
+ }
+ p->pInode->pShmNode = 0;
+ sqlite3_free(p);
+ }
+}
+
+/*
+** Open a shared-memory area associated with open database file pDbFd.
+** This particular implementation uses mmapped files.
+**
+** The file used to implement shared-memory is in the same directory
+** as the open database file and has the same name as the open database
+** file with the "-shm" suffix added. For example, if the database file
+** is "/home/user1/config.db" then the file that is created and mmapped
+** for shared memory will be called "/home/user1/config.db-shm".
+**
+** Another approach to is to use files in /dev/shm or /dev/tmp or an
+** some other tmpfs mount. But if a file in a different directory
+** from the database file is used, then differing access permissions
+** or a chroot() might cause two different processes on the same
+** database to end up using different files for shared memory -
+** meaning that their memory would not really be shared - resulting
+** in database corruption. Nevertheless, this tmpfs file usage
+** can be enabled at compile-time using -DSQLITE_SHM_DIRECTORY="/dev/shm"
+** or the equivalent. The use of the SQLITE_SHM_DIRECTORY compile-time
+** option results in an incompatible build of SQLite; builds of SQLite
+** that with differing SQLITE_SHM_DIRECTORY settings attempt to use the
+** same database file at the same time, database corruption will likely
+** result. The SQLITE_SHM_DIRECTORY compile-time option is considered
+** "unsupported" and may go away in a future SQLite release.
+**
+** When opening a new shared-memory file, if no other instances of that
+** file are currently open, in this process or in other processes, then
+** the file must be truncated to zero length or have its header cleared.
+**
+** If the original database file (pDbFd) is using the "unix-excl" VFS
+** that means that an exclusive lock is held on the database file and
+** that no other processes are able to read or write the database. In
+** that case, we do not really need shared memory. No shared memory
+** file is created. The shared memory will be simulated with heap memory.
+*/
+static int unixOpenSharedMemory(unixFile *pDbFd){
+ struct unixShm *p = 0; /* The connection to be opened */
+ struct unixShmNode *pShmNode; /* The underlying mmapped file */
+ int rc; /* Result code */
+ unixInodeInfo *pInode; /* The inode of fd */
+ char *zShmFilename; /* Name of the file used for SHM */
+ int nShmFilename; /* Size of the SHM filename in bytes */
+
+ /* Allocate space for the new unixShm object. */
+ p = sqlite3_malloc( sizeof(*p) );
+ if( p==0 ) return SQLITE_NOMEM;
+ memset(p, 0, sizeof(*p));
+ assert( pDbFd->pShm==0 );
+
+ /* Check to see if a unixShmNode object already exists. Reuse an existing
+ ** one if present. Create a new one if necessary.
+ */
+ unixEnterMutex();
+ pInode = pDbFd->pInode;
+ pShmNode = pInode->pShmNode;
+ if( pShmNode==0 ){
+ struct stat sStat; /* fstat() info for database file */
+
+ /* Call fstat() to figure out the permissions on the database file. If
+ ** a new *-shm file is created, an attempt will be made to create it
+ ** with the same permissions.
+ */
+ if( osFstat(pDbFd->h, &sStat) && pInode->bProcessLock==0 ){
+ rc = SQLITE_IOERR_FSTAT;
+ goto shm_open_err;
+ }
+
+#ifdef SQLITE_SHM_DIRECTORY
+ nShmFilename = sizeof(SQLITE_SHM_DIRECTORY) + 31;
+#else
+ nShmFilename = 6 + (int)strlen(pDbFd->zPath);
+#endif
+ pShmNode = sqlite3_malloc( sizeof(*pShmNode) + nShmFilename );
+ if( pShmNode==0 ){
+ rc = SQLITE_NOMEM;
+ goto shm_open_err;
+ }
+ memset(pShmNode, 0, sizeof(*pShmNode)+nShmFilename);
+ zShmFilename = pShmNode->zFilename = (char*)&pShmNode[1];
+#ifdef SQLITE_SHM_DIRECTORY
+ sqlite3_snprintf(nShmFilename, zShmFilename,
+ SQLITE_SHM_DIRECTORY "/sqlite-shm-%x-%x",
+ (u32)sStat.st_ino, (u32)sStat.st_dev);
+#else
+ sqlite3_snprintf(nShmFilename, zShmFilename, "%s-shm", pDbFd->zPath);
+ sqlite3FileSuffix3(pDbFd->zPath, zShmFilename);
+#endif
+ pShmNode->h = -1;
+ pDbFd->pInode->pShmNode = pShmNode;
+ pShmNode->pInode = pDbFd->pInode;
+ pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
+ if( pShmNode->mutex==0 ){
+ rc = SQLITE_NOMEM;
+ goto shm_open_err;
+ }
+
+ if( pInode->bProcessLock==0 ){
+ int openFlags = O_RDWR | O_CREAT;
+ if( sqlite3_uri_boolean(pDbFd->zPath, "readonly_shm", 0) ){
+ openFlags = O_RDONLY;
+ pShmNode->isReadonly = 1;
+ }
+ pShmNode->h = robust_open(zShmFilename, openFlags, (sStat.st_mode&0777));
+ if( pShmNode->h<0 ){
+ rc = unixLogError(SQLITE_CANTOPEN_BKPT, "open", zShmFilename);
+ goto shm_open_err;
+ }
+
+ /* If this process is running as root, make sure that the SHM file
+ ** is owned by the same user that owns the original database. Otherwise,
+ ** the original owner will not be able to connect.
+ */
+ osFchown(pShmNode->h, sStat.st_uid, sStat.st_gid);
+
+ /* Check to see if another process is holding the dead-man switch.
+ ** If not, truncate the file to zero length.
+ */
+ rc = SQLITE_OK;
+ if( unixShmSystemLock(pShmNode, F_WRLCK, UNIX_SHM_DMS, 1)==SQLITE_OK ){
+ if( robust_ftruncate(pShmNode->h, 0) ){
+ rc = unixLogError(SQLITE_IOERR_SHMOPEN, "ftruncate", zShmFilename);
+ }
+ }
+ if( rc==SQLITE_OK ){
+ rc = unixShmSystemLock(pShmNode, F_RDLCK, UNIX_SHM_DMS, 1);
+ }
+ if( rc ) goto shm_open_err;
+ }
+ }
+
+ /* Make the new connection a child of the unixShmNode */
+ p->pShmNode = pShmNode;
+#ifdef SQLITE_DEBUG
+ p->id = pShmNode->nextShmId++;
+#endif
+ pShmNode->nRef++;
+ pDbFd->pShm = p;
+ unixLeaveMutex();
+
+ /* The reference count on pShmNode has already been incremented under
+ ** the cover of the unixEnterMutex() mutex and the pointer from the
+ ** new (struct unixShm) object to the pShmNode has been set. All that is
+ ** left to do is to link the new object into the linked list starting
+ ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex
+ ** mutex.
+ */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ p->pNext = pShmNode->pFirst;
+ pShmNode->pFirst = p;
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return SQLITE_OK;
+
+ /* Jump here on any error */
+shm_open_err:
+ unixShmPurge(pDbFd); /* This call frees pShmNode if required */
+ sqlite3_free(p);
+ unixLeaveMutex();
+ return rc;
+}
+
+/*
+** This function is called to obtain a pointer to region iRegion of the
+** shared-memory associated with the database file fd. Shared-memory regions
+** are numbered starting from zero. Each shared-memory region is szRegion
+** bytes in size.
+**
+** If an error occurs, an error code is returned and *pp is set to NULL.
+**
+** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
+** region has not been allocated (by any client, including one running in a
+** separate process), then *pp is set to NULL and SQLITE_OK returned. If
+** bExtend is non-zero and the requested shared-memory region has not yet
+** been allocated, it is allocated by this function.
+**
+** If the shared-memory region has already been allocated or is allocated by
+** this call as described above, then it is mapped into this processes
+** address space (if it is not already), *pp is set to point to the mapped
+** memory and SQLITE_OK returned.
+*/
+static int unixShmMap(
+ sqlite3_file *fd, /* Handle open on database file */
+ int iRegion, /* Region to retrieve */
+ int szRegion, /* Size of regions */
+ int bExtend, /* True to extend file if necessary */
+ void volatile **pp /* OUT: Mapped memory */
+){
+ unixFile *pDbFd = (unixFile*)fd;
+ unixShm *p;
+ unixShmNode *pShmNode;
+ int rc = SQLITE_OK;
+ int nShmPerMap = unixShmRegionPerMap();
+ int nReqRegion;
+
+ /* If the shared-memory file has not yet been opened, open it now. */
+ if( pDbFd->pShm==0 ){
+ rc = unixOpenSharedMemory(pDbFd);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+
+ p = pDbFd->pShm;
+ pShmNode = p->pShmNode;
+ sqlite3_mutex_enter(pShmNode->mutex);
+ assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+ assert( pShmNode->pInode==pDbFd->pInode );
+ assert( pShmNode->h>=0 || pDbFd->pInode->bProcessLock==1 );
+ assert( pShmNode->h<0 || pDbFd->pInode->bProcessLock==0 );
+
+ /* Minimum number of regions required to be mapped. */
+ nReqRegion = ((iRegion+nShmPerMap) / nShmPerMap) * nShmPerMap;
+
+ if( pShmNode->nRegionszRegion = szRegion;
+
+ if( pShmNode->h>=0 ){
+ /* The requested region is not mapped into this processes address space.
+ ** Check to see if it has been allocated (i.e. if the wal-index file is
+ ** large enough to contain the requested region).
+ */
+ if( osFstat(pShmNode->h, &sStat) ){
+ rc = SQLITE_IOERR_SHMSIZE;
+ goto shmpage_out;
+ }
+
+ if( sStat.st_sizeh, iPg*pgsz + pgsz-1, "", 1, 0)!=1 ){
+ const char *zFile = pShmNode->zFilename;
+ rc = unixLogError(SQLITE_IOERR_SHMSIZE, "write", zFile);
+ goto shmpage_out;
+ }
+ }
+ }
+ }
+ }
+
+ /* Map the requested memory region into this processes address space. */
+ apNew = (char **)sqlite3_realloc(
+ pShmNode->apRegion, nReqRegion*sizeof(char *)
+ );
+ if( !apNew ){
+ rc = SQLITE_IOERR_NOMEM;
+ goto shmpage_out;
+ }
+ pShmNode->apRegion = apNew;
+ while( pShmNode->nRegionh>=0 ){
+ pMem = osMmap(0, nMap,
+ pShmNode->isReadonly ? PROT_READ : PROT_READ|PROT_WRITE,
+ MAP_SHARED, pShmNode->h, szRegion*(i64)pShmNode->nRegion
+ );
+ if( pMem==MAP_FAILED ){
+ rc = unixLogError(SQLITE_IOERR_SHMMAP, "mmap", pShmNode->zFilename);
+ goto shmpage_out;
+ }
+ }else{
+ pMem = sqlite3_malloc(szRegion);
+ if( pMem==0 ){
+ rc = SQLITE_NOMEM;
+ goto shmpage_out;
+ }
+ memset(pMem, 0, szRegion);
+ }
+
+ for(i=0; iapRegion[pShmNode->nRegion+i] = &((char*)pMem)[szRegion*i];
+ }
+ pShmNode->nRegion += nShmPerMap;
+ }
+ }
+
+shmpage_out:
+ if( pShmNode->nRegion>iRegion ){
+ *pp = pShmNode->apRegion[iRegion];
+ }else{
+ *pp = 0;
+ }
+ if( pShmNode->isReadonly && rc==SQLITE_OK ) rc = SQLITE_READONLY;
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return rc;
+}
+
+/*
+** Change the lock state for a shared-memory segment.
+**
+** Note that the relationship between SHAREd and EXCLUSIVE locks is a little
+** different here than in posix. In xShmLock(), one can go from unlocked
+** to shared and back or from unlocked to exclusive and back. But one may
+** not go from shared to exclusive or from exclusive to shared.
+*/
+static int unixShmLock(
+ sqlite3_file *fd, /* Database file holding the shared memory */
+ int ofst, /* First lock to acquire or release */
+ int n, /* Number of locks to acquire or release */
+ int flags /* What to do with the lock */
+){
+ unixFile *pDbFd = (unixFile*)fd; /* Connection holding shared memory */
+ unixShm *p = pDbFd->pShm; /* The shared memory being locked */
+ unixShm *pX; /* For looping over all siblings */
+ unixShmNode *pShmNode = p->pShmNode; /* The underlying file iNode */
+ int rc = SQLITE_OK; /* Result code */
+ u16 mask; /* Mask of locks to take or release */
+
+ assert( pShmNode==pDbFd->pInode->pShmNode );
+ assert( pShmNode->pInode==pDbFd->pInode );
+ assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
+ assert( n>=1 );
+ assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
+ assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
+ assert( pShmNode->h>=0 || pDbFd->pInode->bProcessLock==1 );
+ assert( pShmNode->h<0 || pDbFd->pInode->bProcessLock==0 );
+
+ mask = (1<<(ofst+n)) - (1<1 || mask==(1<mutex);
+ if( flags & SQLITE_SHM_UNLOCK ){
+ u16 allMask = 0; /* Mask of locks held by siblings */
+
+ /* See if any siblings hold this same lock */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( pX==p ) continue;
+ assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
+ allMask |= pX->sharedMask;
+ }
+
+ /* Unlock the system-level locks */
+ if( (mask & allMask)==0 ){
+ rc = unixShmSystemLock(pShmNode, F_UNLCK, ofst+UNIX_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+
+ /* Undo the local locks */
+ if( rc==SQLITE_OK ){
+ p->exclMask &= ~mask;
+ p->sharedMask &= ~mask;
+ }
+ }else if( flags & SQLITE_SHM_SHARED ){
+ u16 allShared = 0; /* Union of locks held by connections other than "p" */
+
+ /* Find out which shared locks are already held by sibling connections.
+ ** If any sibling already holds an exclusive lock, go ahead and return
+ ** SQLITE_BUSY.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ allShared |= pX->sharedMask;
+ }
+
+ /* Get shared locks at the system level, if necessary */
+ if( rc==SQLITE_OK ){
+ if( (allShared & mask)==0 ){
+ rc = unixShmSystemLock(pShmNode, F_RDLCK, ofst+UNIX_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+ }
+
+ /* Get the local shared locks */
+ if( rc==SQLITE_OK ){
+ p->sharedMask |= mask;
+ }
+ }else{
+ /* Make sure no sibling connections hold locks that will block this
+ ** lock. If any do, return SQLITE_BUSY right away.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ }
+
+ /* Get the exclusive locks at the system level. Then if successful
+ ** also mark the local connection as being locked.
+ */
+ if( rc==SQLITE_OK ){
+ rc = unixShmSystemLock(pShmNode, F_WRLCK, ofst+UNIX_SHM_BASE, n);
+ if( rc==SQLITE_OK ){
+ assert( (p->sharedMask & mask)==0 );
+ p->exclMask |= mask;
+ }
+ }
+ }
+ sqlite3_mutex_leave(pShmNode->mutex);
+ OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x\n",
+ p->id, getpid(), p->sharedMask, p->exclMask));
+ return rc;
+}
+
+/*
+** Implement a memory barrier or memory fence on shared memory.
+**
+** All loads and stores begun before the barrier must complete before
+** any load or store begun after the barrier.
+*/
+static void unixShmBarrier(
+ sqlite3_file *fd /* Database file holding the shared memory */
+){
+ UNUSED_PARAMETER(fd);
+ unixEnterMutex();
+ unixLeaveMutex();
+}
+
+/*
+** Close a connection to shared-memory. Delete the underlying
+** storage if deleteFlag is true.
+**
+** If there is no shared memory associated with the connection then this
+** routine is a harmless no-op.
+*/
+static int unixShmUnmap(
+ sqlite3_file *fd, /* The underlying database file */
+ int deleteFlag /* Delete shared-memory if true */
+){
+ unixShm *p; /* The connection to be closed */
+ unixShmNode *pShmNode; /* The underlying shared-memory file */
+ unixShm **pp; /* For looping over sibling connections */
+ unixFile *pDbFd; /* The underlying database file */
+
+ pDbFd = (unixFile*)fd;
+ p = pDbFd->pShm;
+ if( p==0 ) return SQLITE_OK;
+ pShmNode = p->pShmNode;
+
+ assert( pShmNode==pDbFd->pInode->pShmNode );
+ assert( pShmNode->pInode==pDbFd->pInode );
+
+ /* Remove connection p from the set of connections associated
+ ** with pShmNode */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
+ *pp = p->pNext;
+
+ /* Free the connection p */
+ sqlite3_free(p);
+ pDbFd->pShm = 0;
+ sqlite3_mutex_leave(pShmNode->mutex);
+
+ /* If pShmNode->nRef has reached 0, then close the underlying
+ ** shared-memory file, too */
+ unixEnterMutex();
+ assert( pShmNode->nRef>0 );
+ pShmNode->nRef--;
+ if( pShmNode->nRef==0 ){
+ if( deleteFlag && pShmNode->h>=0 ) osUnlink(pShmNode->zFilename);
+ unixShmPurge(pDbFd);
+ }
+ unixLeaveMutex();
+
+ return SQLITE_OK;
+}
+
+
+#else
+# define unixShmMap 0
+# define unixShmLock 0
+# define unixShmBarrier 0
+# define unixShmUnmap 0
+#endif /* #ifndef SQLITE_OMIT_WAL */
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/*
+** If it is currently memory mapped, unmap file pFd.
+*/
+static void unixUnmapfile(unixFile *pFd){
+ assert( pFd->nFetchOut==0 );
+ if( pFd->pMapRegion ){
+ osMunmap(pFd->pMapRegion, pFd->mmapSizeActual);
+ pFd->pMapRegion = 0;
+ pFd->mmapSize = 0;
+ pFd->mmapSizeActual = 0;
+ }
+}
+
+/*
+** Attempt to set the size of the memory mapping maintained by file
+** descriptor pFd to nNew bytes. Any existing mapping is discarded.
+**
+** If successful, this function sets the following variables:
+**
+** unixFile.pMapRegion
+** unixFile.mmapSize
+** unixFile.mmapSizeActual
+**
+** If unsuccessful, an error message is logged via sqlite3_log() and
+** the three variables above are zeroed. In this case SQLite should
+** continue accessing the database using the xRead() and xWrite()
+** methods.
+*/
+static void unixRemapfile(
+ unixFile *pFd, /* File descriptor object */
+ i64 nNew /* Required mapping size */
+){
+ const char *zErr = "mmap";
+ int h = pFd->h; /* File descriptor open on db file */
+ u8 *pOrig = (u8 *)pFd->pMapRegion; /* Pointer to current file mapping */
+ i64 nOrig = pFd->mmapSizeActual; /* Size of pOrig region in bytes */
+ u8 *pNew = 0; /* Location of new mapping */
+ int flags = PROT_READ; /* Flags to pass to mmap() */
+
+ assert( pFd->nFetchOut==0 );
+ assert( nNew>pFd->mmapSize );
+ assert( nNew<=pFd->mmapSizeMax );
+ assert( nNew>0 );
+ assert( pFd->mmapSizeActual>=pFd->mmapSize );
+ assert( MAP_FAILED!=0 );
+
+ if( (pFd->ctrlFlags & UNIXFILE_RDONLY)==0 ) flags |= PROT_WRITE;
+
+ if( pOrig ){
+#if HAVE_MREMAP
+ i64 nReuse = pFd->mmapSize;
+#else
+ const int szSyspage = osGetpagesize();
+ i64 nReuse = (pFd->mmapSize & ~(szSyspage-1));
+#endif
+ u8 *pReq = &pOrig[nReuse];
+
+ /* Unmap any pages of the existing mapping that cannot be reused. */
+ if( nReuse!=nOrig ){
+ osMunmap(pReq, nOrig-nReuse);
+ }
+
+#if HAVE_MREMAP
+ pNew = osMremap(pOrig, nReuse, nNew, MREMAP_MAYMOVE);
+ zErr = "mremap";
+#else
+ pNew = osMmap(pReq, nNew-nReuse, flags, MAP_SHARED, h, nReuse);
+ if( pNew!=MAP_FAILED ){
+ if( pNew!=pReq ){
+ osMunmap(pNew, nNew - nReuse);
+ pNew = 0;
+ }else{
+ pNew = pOrig;
+ }
+ }
+#endif
+
+ /* The attempt to extend the existing mapping failed. Free it. */
+ if( pNew==MAP_FAILED || pNew==0 ){
+ osMunmap(pOrig, nReuse);
+ }
+ }
+
+ /* If pNew is still NULL, try to create an entirely new mapping. */
+ if( pNew==0 ){
+ pNew = osMmap(0, nNew, flags, MAP_SHARED, h, 0);
+ }
+
+ if( pNew==MAP_FAILED ){
+ pNew = 0;
+ nNew = 0;
+ unixLogError(SQLITE_OK, zErr, pFd->zPath);
+
+ /* If the mmap() above failed, assume that all subsequent mmap() calls
+ ** will probably fail too. Fall back to using xRead/xWrite exclusively
+ ** in this case. */
+ pFd->mmapSizeMax = 0;
+ }
+ pFd->pMapRegion = (void *)pNew;
+ pFd->mmapSize = pFd->mmapSizeActual = nNew;
+}
+
+/*
+** Memory map or remap the file opened by file-descriptor pFd (if the file
+** is already mapped, the existing mapping is replaced by the new). Or, if
+** there already exists a mapping for this file, and there are still
+** outstanding xFetch() references to it, this function is a no-op.
+**
+** If parameter nByte is non-negative, then it is the requested size of
+** the mapping to create. Otherwise, if nByte is less than zero, then the
+** requested size is the size of the file on disk. The actual size of the
+** created mapping is either the requested size or the value configured
+** using SQLITE_FCNTL_MMAP_LIMIT, whichever is smaller.
+**
+** SQLITE_OK is returned if no error occurs (even if the mapping is not
+** recreated as a result of outstanding references) or an SQLite error
+** code otherwise.
+*/
+static int unixMapfile(unixFile *pFd, i64 nByte){
+ i64 nMap = nByte;
+ int rc;
+
+ assert( nMap>=0 || pFd->nFetchOut==0 );
+ if( pFd->nFetchOut>0 ) return SQLITE_OK;
+
+ if( nMap<0 ){
+ struct stat statbuf; /* Low-level file information */
+ rc = osFstat(pFd->h, &statbuf);
+ if( rc!=SQLITE_OK ){
+ return SQLITE_IOERR_FSTAT;
+ }
+ nMap = statbuf.st_size;
+ }
+ if( nMap>pFd->mmapSizeMax ){
+ nMap = pFd->mmapSizeMax;
+ }
+
+ if( nMap!=pFd->mmapSize ){
+ if( nMap>0 ){
+ unixRemapfile(pFd, nMap);
+ }else{
+ unixUnmapfile(pFd);
+ }
+ }
+
+ return SQLITE_OK;
+}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+
+/*
+** If possible, return a pointer to a mapping of file fd starting at offset
+** iOff. The mapping must be valid for at least nAmt bytes.
+**
+** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
+** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
+** Finally, if an error does occur, return an SQLite error code. The final
+** value of *pp is undefined in this case.
+**
+** If this function does return a pointer, the caller must eventually
+** release the reference by calling unixUnfetch().
+*/
+static int unixFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
+#if SQLITE_MAX_MMAP_SIZE>0
+ unixFile *pFd = (unixFile *)fd; /* The underlying database file */
+#endif
+ *pp = 0;
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( pFd->mmapSizeMax>0 ){
+ if( pFd->pMapRegion==0 ){
+ int rc = unixMapfile(pFd, -1);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ if( pFd->mmapSize >= iOff+nAmt ){
+ *pp = &((u8 *)pFd->pMapRegion)[iOff];
+ pFd->nFetchOut++;
+ }
+ }
+#endif
+ return SQLITE_OK;
+}
+
+/*
+** If the third argument is non-NULL, then this function releases a
+** reference obtained by an earlier call to unixFetch(). The second
+** argument passed to this function must be the same as the corresponding
+** argument that was passed to the unixFetch() invocation.
+**
+** Or, if the third argument is NULL, then this function is being called
+** to inform the VFS layer that, according to POSIX, any existing mapping
+** may now be invalid and should be unmapped.
+*/
+static int unixUnfetch(sqlite3_file *fd, i64 iOff, void *p){
+#if SQLITE_MAX_MMAP_SIZE>0
+ unixFile *pFd = (unixFile *)fd; /* The underlying database file */
+ UNUSED_PARAMETER(iOff);
+
+ /* If p==0 (unmap the entire file) then there must be no outstanding
+ ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
+ ** then there must be at least one outstanding. */
+ assert( (p==0)==(pFd->nFetchOut==0) );
+
+ /* If p!=0, it must match the iOff value. */
+ assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
+
+ if( p ){
+ pFd->nFetchOut--;
+ }else{
+ unixUnmapfile(pFd);
+ }
+
+ assert( pFd->nFetchOut>=0 );
+#else
+ UNUSED_PARAMETER(fd);
+ UNUSED_PARAMETER(p);
+ UNUSED_PARAMETER(iOff);
+#endif
+ return SQLITE_OK;
+}
+
+/*
+** Here ends the implementation of all sqlite3_file methods.
+**
+********************** End sqlite3_file Methods *******************************
+******************************************************************************/
+
+/*
+** This division contains definitions of sqlite3_io_methods objects that
+** implement various file locking strategies. It also contains definitions
+** of "finder" functions. A finder-function is used to locate the appropriate
+** sqlite3_io_methods object for a particular database file. The pAppData
+** field of the sqlite3_vfs VFS objects are initialized to be pointers to
+** the correct finder-function for that VFS.
+**
+** Most finder functions return a pointer to a fixed sqlite3_io_methods
+** object. The only interesting finder-function is autolockIoFinder, which
+** looks at the filesystem type and tries to guess the best locking
+** strategy from that.
+**
+** For finder-funtion F, two objects are created:
+**
+** (1) The real finder-function named "FImpt()".
+**
+** (2) A constant pointer to this function named just "F".
+**
+**
+** A pointer to the F pointer is used as the pAppData value for VFS
+** objects. We have to do this instead of letting pAppData point
+** directly at the finder-function since C90 rules prevent a void*
+** from be cast into a function pointer.
+**
+**
+** Each instance of this macro generates two objects:
+**
+** * A constant sqlite3_io_methods object call METHOD that has locking
+** methods CLOSE, LOCK, UNLOCK, CKRESLOCK.
+**
+** * An I/O method finder function called FINDER that returns a pointer
+** to the METHOD object in the previous bullet.
+*/
+#define IOMETHODS(FINDER, METHOD, VERSION, CLOSE, LOCK, UNLOCK, CKLOCK) \
+static const sqlite3_io_methods METHOD = { \
+ VERSION, /* iVersion */ \
+ CLOSE, /* xClose */ \
+ unixRead, /* xRead */ \
+ unixWrite, /* xWrite */ \
+ unixTruncate, /* xTruncate */ \
+ unixSync, /* xSync */ \
+ unixFileSize, /* xFileSize */ \
+ LOCK, /* xLock */ \
+ UNLOCK, /* xUnlock */ \
+ CKLOCK, /* xCheckReservedLock */ \
+ unixFileControl, /* xFileControl */ \
+ unixSectorSize, /* xSectorSize */ \
+ unixDeviceCharacteristics, /* xDeviceCapabilities */ \
+ unixShmMap, /* xShmMap */ \
+ unixShmLock, /* xShmLock */ \
+ unixShmBarrier, /* xShmBarrier */ \
+ unixShmUnmap, /* xShmUnmap */ \
+ unixFetch, /* xFetch */ \
+ unixUnfetch, /* xUnfetch */ \
+}; \
+static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){ \
+ UNUSED_PARAMETER(z); UNUSED_PARAMETER(p); \
+ return &METHOD; \
+} \
+static const sqlite3_io_methods *(*const FINDER)(const char*,unixFile *p) \
+ = FINDER##Impl;
+
+/*
+** Here are all of the sqlite3_io_methods objects for each of the
+** locking strategies. Functions that return pointers to these methods
+** are also created.
+*/
+IOMETHODS(
+ posixIoFinder, /* Finder function name */
+ posixIoMethods, /* sqlite3_io_methods object name */
+ 3, /* shared memory and mmap are enabled */
+ unixClose, /* xClose method */
+ unixLock, /* xLock method */
+ unixUnlock, /* xUnlock method */
+ unixCheckReservedLock /* xCheckReservedLock method */
+)
+IOMETHODS(
+ nolockIoFinder, /* Finder function name */
+ nolockIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ nolockClose, /* xClose method */
+ nolockLock, /* xLock method */
+ nolockUnlock, /* xUnlock method */
+ nolockCheckReservedLock /* xCheckReservedLock method */
+)
+IOMETHODS(
+ dotlockIoFinder, /* Finder function name */
+ dotlockIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ dotlockClose, /* xClose method */
+ dotlockLock, /* xLock method */
+ dotlockUnlock, /* xUnlock method */
+ dotlockCheckReservedLock /* xCheckReservedLock method */
+)
+
+#if SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORKS
+IOMETHODS(
+ flockIoFinder, /* Finder function name */
+ flockIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ flockClose, /* xClose method */
+ flockLock, /* xLock method */
+ flockUnlock, /* xUnlock method */
+ flockCheckReservedLock /* xCheckReservedLock method */
+)
+#endif
+
+#if OS_VXWORKS
+IOMETHODS(
+ semIoFinder, /* Finder function name */
+ semIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ semClose, /* xClose method */
+ semLock, /* xLock method */
+ semUnlock, /* xUnlock method */
+ semCheckReservedLock /* xCheckReservedLock method */
+)
+#endif
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+IOMETHODS(
+ afpIoFinder, /* Finder function name */
+ afpIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ afpClose, /* xClose method */
+ afpLock, /* xLock method */
+ afpUnlock, /* xUnlock method */
+ afpCheckReservedLock /* xCheckReservedLock method */
+)
+#endif
+
+/*
+** The proxy locking method is a "super-method" in the sense that it
+** opens secondary file descriptors for the conch and lock files and
+** it uses proxy, dot-file, AFP, and flock() locking methods on those
+** secondary files. For this reason, the division that implements
+** proxy locking is located much further down in the file. But we need
+** to go ahead and define the sqlite3_io_methods and finder function
+** for proxy locking here. So we forward declare the I/O methods.
+*/
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+static int proxyClose(sqlite3_file*);
+static int proxyLock(sqlite3_file*, int);
+static int proxyUnlock(sqlite3_file*, int);
+static int proxyCheckReservedLock(sqlite3_file*, int*);
+IOMETHODS(
+ proxyIoFinder, /* Finder function name */
+ proxyIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ proxyClose, /* xClose method */
+ proxyLock, /* xLock method */
+ proxyUnlock, /* xUnlock method */
+ proxyCheckReservedLock /* xCheckReservedLock method */
+)
+#endif
+
+/* nfs lockd on OSX 10.3+ doesn't clear write locks when a read lock is set */
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+IOMETHODS(
+ nfsIoFinder, /* Finder function name */
+ nfsIoMethods, /* sqlite3_io_methods object name */
+ 1, /* shared memory is disabled */
+ unixClose, /* xClose method */
+ unixLock, /* xLock method */
+ nfsUnlock, /* xUnlock method */
+ unixCheckReservedLock /* xCheckReservedLock method */
+)
+#endif
+
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+/*
+** This "finder" function attempts to determine the best locking strategy
+** for the database file "filePath". It then returns the sqlite3_io_methods
+** object that implements that strategy.
+**
+** This is for MacOSX only.
+*/
+static const sqlite3_io_methods *autolockIoFinderImpl(
+ const char *filePath, /* name of the database file */
+ unixFile *pNew /* open file object for the database file */
+){
+ static const struct Mapping {
+ const char *zFilesystem; /* Filesystem type name */
+ const sqlite3_io_methods *pMethods; /* Appropriate locking method */
+ } aMap[] = {
+ { "hfs", &posixIoMethods },
+ { "ufs", &posixIoMethods },
+ { "afpfs", &afpIoMethods },
+ { "smbfs", &afpIoMethods },
+ { "webdav", &nolockIoMethods },
+ { 0, 0 }
+ };
+ int i;
+ struct statfs fsInfo;
+ struct flock lockInfo;
+
+ if( !filePath ){
+ /* If filePath==NULL that means we are dealing with a transient file
+ ** that does not need to be locked. */
+ return &nolockIoMethods;
+ }
+ if( statfs(filePath, &fsInfo) != -1 ){
+ if( fsInfo.f_flags & MNT_RDONLY ){
+ return &nolockIoMethods;
+ }
+ for(i=0; aMap[i].zFilesystem; i++){
+ if( strcmp(fsInfo.f_fstypename, aMap[i].zFilesystem)==0 ){
+ return aMap[i].pMethods;
+ }
+ }
+ }
+
+ /* Default case. Handles, amongst others, "nfs".
+ ** Test byte-range lock using fcntl(). If the call succeeds,
+ ** assume that the file-system supports POSIX style locks.
+ */
+ lockInfo.l_len = 1;
+ lockInfo.l_start = 0;
+ lockInfo.l_whence = SEEK_SET;
+ lockInfo.l_type = F_RDLCK;
+ if( osFcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
+ if( strcmp(fsInfo.f_fstypename, "nfs")==0 ){
+ return &nfsIoMethods;
+ } else {
+ return &posixIoMethods;
+ }
+ }else{
+ return &dotlockIoMethods;
+ }
+}
+static const sqlite3_io_methods
+ *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+
+#if OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE
+/*
+** This "finder" function attempts to determine the best locking strategy
+** for the database file "filePath". It then returns the sqlite3_io_methods
+** object that implements that strategy.
+**
+** This is for VXWorks only.
+*/
+static const sqlite3_io_methods *autolockIoFinderImpl(
+ const char *filePath, /* name of the database file */
+ unixFile *pNew /* the open file object */
+){
+ struct flock lockInfo;
+
+ if( !filePath ){
+ /* If filePath==NULL that means we are dealing with a transient file
+ ** that does not need to be locked. */
+ return &nolockIoMethods;
+ }
+
+ /* Test if fcntl() is supported and use POSIX style locks.
+ ** Otherwise fall back to the named semaphore method.
+ */
+ lockInfo.l_len = 1;
+ lockInfo.l_start = 0;
+ lockInfo.l_whence = SEEK_SET;
+ lockInfo.l_type = F_RDLCK;
+ if( osFcntl(pNew->h, F_GETLK, &lockInfo)!=-1 ) {
+ return &posixIoMethods;
+ }else{
+ return &semIoMethods;
+ }
+}
+static const sqlite3_io_methods
+ *(*const autolockIoFinder)(const char*,unixFile*) = autolockIoFinderImpl;
+
+#endif /* OS_VXWORKS && SQLITE_ENABLE_LOCKING_STYLE */
+
+/*
+** An abstract type for a pointer to a IO method finder function:
+*/
+typedef const sqlite3_io_methods *(*finder_type)(const char*,unixFile*);
+
+
+/****************************************************************************
+**************************** sqlite3_vfs methods ****************************
+**
+** This division contains the implementation of methods on the
+** sqlite3_vfs object.
+*/
+
+/*
+** Initialize the contents of the unixFile structure pointed to by pId.
+*/
+static int fillInUnixFile(
+ sqlite3_vfs *pVfs, /* Pointer to vfs object */
+ int h, /* Open file descriptor of file being opened */
+ sqlite3_file *pId, /* Write to the unixFile structure here */
+ const char *zFilename, /* Name of the file being opened */
+ int ctrlFlags /* Zero or more UNIXFILE_* values */
+){
+ const sqlite3_io_methods *pLockingStyle;
+ unixFile *pNew = (unixFile *)pId;
+ int rc = SQLITE_OK;
+
+ assert( pNew->pInode==NULL );
+
+ /* Usually the path zFilename should not be a relative pathname. The
+ ** exception is when opening the proxy "conch" file in builds that
+ ** include the special Apple locking styles.
+ */
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+ assert( zFilename==0 || zFilename[0]=='/'
+ || pVfs->pAppData==(void*)&autolockIoFinder );
+#else
+ assert( zFilename==0 || zFilename[0]=='/' );
+#endif
+
+ /* No locking occurs in temporary files */
+ assert( zFilename!=0 || (ctrlFlags & UNIXFILE_NOLOCK)!=0 );
+
+ OSTRACE(("OPEN %-3d %s\n", h, zFilename));
+ pNew->h = h;
+ pNew->pVfs = pVfs;
+ pNew->zPath = zFilename;
+ pNew->ctrlFlags = (u8)ctrlFlags;
+#if SQLITE_MAX_MMAP_SIZE>0
+ pNew->mmapSizeMax = sqlite3GlobalConfig.szMmap;
+#endif
+ if( sqlite3_uri_boolean(((ctrlFlags & UNIXFILE_URI) ? zFilename : 0),
+ "psow", SQLITE_POWERSAFE_OVERWRITE) ){
+ pNew->ctrlFlags |= UNIXFILE_PSOW;
+ }
+ if( strcmp(pVfs->zName,"unix-excl")==0 ){
+ pNew->ctrlFlags |= UNIXFILE_EXCL;
+ }
+
+#if OS_VXWORKS
+ pNew->pId = vxworksFindFileId(zFilename);
+ if( pNew->pId==0 ){
+ ctrlFlags |= UNIXFILE_NOLOCK;
+ rc = SQLITE_NOMEM;
+ }
+#endif
+
+ if( ctrlFlags & UNIXFILE_NOLOCK ){
+ pLockingStyle = &nolockIoMethods;
+ }else{
+ pLockingStyle = (**(finder_type*)pVfs->pAppData)(zFilename, pNew);
+#if SQLITE_ENABLE_LOCKING_STYLE
+ /* Cache zFilename in the locking context (AFP and dotlock override) for
+ ** proxyLock activation is possible (remote proxy is based on db name)
+ ** zFilename remains valid until file is closed, to support */
+ pNew->lockingContext = (void*)zFilename;
+#endif
+ }
+
+ if( pLockingStyle == &posixIoMethods
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+ || pLockingStyle == &nfsIoMethods
+#endif
+ ){
+ unixEnterMutex();
+ rc = findInodeInfo(pNew, &pNew->pInode);
+ if( rc!=SQLITE_OK ){
+ /* If an error occurred in findInodeInfo(), close the file descriptor
+ ** immediately, before releasing the mutex. findInodeInfo() may fail
+ ** in two scenarios:
+ **
+ ** (a) A call to fstat() failed.
+ ** (b) A malloc failed.
+ **
+ ** Scenario (b) may only occur if the process is holding no other
+ ** file descriptors open on the same file. If there were other file
+ ** descriptors on this file, then no malloc would be required by
+ ** findInodeInfo(). If this is the case, it is quite safe to close
+ ** handle h - as it is guaranteed that no posix locks will be released
+ ** by doing so.
+ **
+ ** If scenario (a) caused the error then things are not so safe. The
+ ** implicit assumption here is that if fstat() fails, things are in
+ ** such bad shape that dropping a lock or two doesn't matter much.
+ */
+ robust_close(pNew, h, __LINE__);
+ h = -1;
+ }
+ unixLeaveMutex();
+ }
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+ else if( pLockingStyle == &afpIoMethods ){
+ /* AFP locking uses the file path so it needs to be included in
+ ** the afpLockingContext.
+ */
+ afpLockingContext *pCtx;
+ pNew->lockingContext = pCtx = sqlite3_malloc( sizeof(*pCtx) );
+ if( pCtx==0 ){
+ rc = SQLITE_NOMEM;
+ }else{
+ /* NB: zFilename exists and remains valid until the file is closed
+ ** according to requirement F11141. So we do not need to make a
+ ** copy of the filename. */
+ pCtx->dbPath = zFilename;
+ pCtx->reserved = 0;
+ srandomdev();
+ unixEnterMutex();
+ rc = findInodeInfo(pNew, &pNew->pInode);
+ if( rc!=SQLITE_OK ){
+ sqlite3_free(pNew->lockingContext);
+ robust_close(pNew, h, __LINE__);
+ h = -1;
+ }
+ unixLeaveMutex();
+ }
+ }
+#endif
+
+ else if( pLockingStyle == &dotlockIoMethods ){
+ /* Dotfile locking uses the file path so it needs to be included in
+ ** the dotlockLockingContext
+ */
+ char *zLockFile;
+ int nFilename;
+ assert( zFilename!=0 );
+ nFilename = (int)strlen(zFilename) + 6;
+ zLockFile = (char *)sqlite3_malloc(nFilename);
+ if( zLockFile==0 ){
+ rc = SQLITE_NOMEM;
+ }else{
+ sqlite3_snprintf(nFilename, zLockFile, "%s" DOTLOCK_SUFFIX, zFilename);
+ }
+ pNew->lockingContext = zLockFile;
+ }
+
+#if OS_VXWORKS
+ else if( pLockingStyle == &semIoMethods ){
+ /* Named semaphore locking uses the file path so it needs to be
+ ** included in the semLockingContext
+ */
+ unixEnterMutex();
+ rc = findInodeInfo(pNew, &pNew->pInode);
+ if( (rc==SQLITE_OK) && (pNew->pInode->pSem==NULL) ){
+ char *zSemName = pNew->pInode->aSemName;
+ int n;
+ sqlite3_snprintf(MAX_PATHNAME, zSemName, "/%s.sem",
+ pNew->pId->zCanonicalName);
+ for( n=1; zSemName[n]; n++ )
+ if( zSemName[n]=='/' ) zSemName[n] = '_';
+ pNew->pInode->pSem = sem_open(zSemName, O_CREAT, 0666, 1);
+ if( pNew->pInode->pSem == SEM_FAILED ){
+ rc = SQLITE_NOMEM;
+ pNew->pInode->aSemName[0] = '\0';
+ }
+ }
+ unixLeaveMutex();
+ }
+#endif
+
+ pNew->lastErrno = 0;
+#if OS_VXWORKS
+ if( rc!=SQLITE_OK ){
+ if( h>=0 ) robust_close(pNew, h, __LINE__);
+ h = -1;
+ osUnlink(zFilename);
+ pNew->ctrlFlags |= UNIXFILE_DELETE;
+ }
+#endif
+ if( rc!=SQLITE_OK ){
+ if( h>=0 ) robust_close(pNew, h, __LINE__);
+ }else{
+ pNew->pMethod = pLockingStyle;
+ OpenCounter(+1);
+ verifyDbFile(pNew);
+ }
+ return rc;
+}
+
+/*
+** Return the name of a directory in which to put temporary files.
+** If no suitable temporary file directory can be found, return NULL.
+*/
+static const char *unixTempFileDir(void){
+ static const char *azDirs[] = {
+ 0,
+ 0,
+ 0,
+ "/var/tmp",
+ "/usr/tmp",
+ "/tmp",
+ 0 /* List terminator */
+ };
+ unsigned int i;
+ struct stat buf;
+ const char *zDir = 0;
+
+ azDirs[0] = sqlite3_temp_directory;
+ if( !azDirs[1] ) azDirs[1] = getenv("SQLITE_TMPDIR");
+ if( !azDirs[2] ) azDirs[2] = getenv("TMPDIR");
+ for(i=0; imxPathname bytes.
+*/
+static int unixGetTempname(int nBuf, char *zBuf){
+ static const unsigned char zChars[] =
+ "abcdefghijklmnopqrstuvwxyz"
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "0123456789";
+ unsigned int i, j;
+ const char *zDir;
+
+ /* It's odd to simulate an io-error here, but really this is just
+ ** using the io-error infrastructure to test that SQLite handles this
+ ** function failing.
+ */
+ SimulateIOError( return SQLITE_IOERR );
+
+ zDir = unixTempFileDir();
+ if( zDir==0 ) zDir = ".";
+
+ /* Check that the output buffer is large enough for the temporary file
+ ** name. If it is not, return SQLITE_ERROR.
+ */
+ if( (strlen(zDir) + strlen(SQLITE_TEMP_FILE_PREFIX) + 18) >= (size_t)nBuf ){
+ return SQLITE_ERROR;
+ }
+
+ do{
+ sqlite3_snprintf(nBuf-18, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX, zDir);
+ j = (int)strlen(zBuf);
+ sqlite3_randomness(15, &zBuf[j]);
+ for(i=0; i<15; i++, j++){
+ zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+ }
+ zBuf[j] = 0;
+ zBuf[j+1] = 0;
+ }while( osAccess(zBuf,0)==0 );
+ return SQLITE_OK;
+}
+
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+/*
+** Routine to transform a unixFile into a proxy-locking unixFile.
+** Implementation in the proxy-lock division, but used by unixOpen()
+** if SQLITE_PREFER_PROXY_LOCKING is defined.
+*/
+static int proxyTransformUnixFile(unixFile*, const char*);
+#endif
+
+/*
+** Search for an unused file descriptor that was opened on the database
+** file (not a journal or master-journal file) identified by pathname
+** zPath with SQLITE_OPEN_XXX flags matching those passed as the second
+** argument to this function.
+**
+** Such a file descriptor may exist if a database connection was closed
+** but the associated file descriptor could not be closed because some
+** other file descriptor open on the same file is holding a file-lock.
+** Refer to comments in the unixClose() function and the lengthy comment
+** describing "Posix Advisory Locking" at the start of this file for
+** further details. Also, ticket #4018.
+**
+** If a suitable file descriptor is found, then it is returned. If no
+** such file descriptor is located, -1 is returned.
+*/
+static UnixUnusedFd *findReusableFd(const char *zPath, int flags){
+ UnixUnusedFd *pUnused = 0;
+
+ /* Do not search for an unused file descriptor on vxworks. Not because
+ ** vxworks would not benefit from the change (it might, we're not sure),
+ ** but because no way to test it is currently available. It is better
+ ** not to risk breaking vxworks support for the sake of such an obscure
+ ** feature. */
+#if !OS_VXWORKS
+ struct stat sStat; /* Results of stat() call */
+
+ /* A stat() call may fail for various reasons. If this happens, it is
+ ** almost certain that an open() call on the same path will also fail.
+ ** For this reason, if an error occurs in the stat() call here, it is
+ ** ignored and -1 is returned. The caller will try to open a new file
+ ** descriptor on the same path, fail, and return an error to SQLite.
+ **
+ ** Even if a subsequent open() call does succeed, the consequences of
+ ** not searching for a resusable file descriptor are not dire. */
+ if( 0==osStat(zPath, &sStat) ){
+ unixInodeInfo *pInode;
+
+ unixEnterMutex();
+ pInode = inodeList;
+ while( pInode && (pInode->fileId.dev!=sStat.st_dev
+ || pInode->fileId.ino!=sStat.st_ino) ){
+ pInode = pInode->pNext;
+ }
+ if( pInode ){
+ UnixUnusedFd **pp;
+ for(pp=&pInode->pUnused; *pp && (*pp)->flags!=flags; pp=&((*pp)->pNext));
+ pUnused = *pp;
+ if( pUnused ){
+ *pp = pUnused->pNext;
+ }
+ }
+ unixLeaveMutex();
+ }
+#endif /* if !OS_VXWORKS */
+ return pUnused;
+}
+
+/*
+** This function is called by unixOpen() to determine the unix permissions
+** to create new files with. If no error occurs, then SQLITE_OK is returned
+** and a value suitable for passing as the third argument to open(2) is
+** written to *pMode. If an IO error occurs, an SQLite error code is
+** returned and the value of *pMode is not modified.
+**
+** In most cases cases, this routine sets *pMode to 0, which will become
+** an indication to robust_open() to create the file using
+** SQLITE_DEFAULT_FILE_PERMISSIONS adjusted by the umask.
+** But if the file being opened is a WAL or regular journal file, then
+** this function queries the file-system for the permissions on the
+** corresponding database file and sets *pMode to this value. Whenever
+** possible, WAL and journal files are created using the same permissions
+** as the associated database file.
+**
+** If the SQLITE_ENABLE_8_3_NAMES option is enabled, then the
+** original filename is unavailable. But 8_3_NAMES is only used for
+** FAT filesystems and permissions do not matter there, so just use
+** the default permissions.
+*/
+static int findCreateFileMode(
+ const char *zPath, /* Path of file (possibly) being created */
+ int flags, /* Flags passed as 4th argument to xOpen() */
+ mode_t *pMode, /* OUT: Permissions to open file with */
+ uid_t *pUid, /* OUT: uid to set on the file */
+ gid_t *pGid /* OUT: gid to set on the file */
+){
+ int rc = SQLITE_OK; /* Return Code */
+ *pMode = 0;
+ *pUid = 0;
+ *pGid = 0;
+ if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
+ char zDb[MAX_PATHNAME+1]; /* Database file path */
+ int nDb; /* Number of valid bytes in zDb */
+ struct stat sStat; /* Output of stat() on database file */
+
+ /* zPath is a path to a WAL or journal file. The following block derives
+ ** the path to the associated database file from zPath. This block handles
+ ** the following naming conventions:
+ **
+ ** "-journal"
+ ** "-wal"
+ ** "-journalNN"
+ ** "-walNN"
+ **
+ ** where NN is a decimal number. The NN naming schemes are
+ ** used by the test_multiplex.c module.
+ */
+ nDb = sqlite3Strlen30(zPath) - 1;
+#ifdef SQLITE_ENABLE_8_3_NAMES
+ while( nDb>0 && sqlite3Isalnum(zPath[nDb]) ) nDb--;
+ if( nDb==0 || zPath[nDb]!='-' ) return SQLITE_OK;
+#else
+ while( zPath[nDb]!='-' ){
+ assert( nDb>0 );
+ assert( zPath[nDb]!='\n' );
+ nDb--;
+ }
+#endif
+ memcpy(zDb, zPath, nDb);
+ zDb[nDb] = '\0';
+
+ if( 0==osStat(zDb, &sStat) ){
+ *pMode = sStat.st_mode & 0777;
+ *pUid = sStat.st_uid;
+ *pGid = sStat.st_gid;
+ }else{
+ rc = SQLITE_IOERR_FSTAT;
+ }
+ }else if( flags & SQLITE_OPEN_DELETEONCLOSE ){
+ *pMode = 0600;
+ }
+ return rc;
+}
+
+/*
+** Open the file zPath.
+**
+** Previously, the SQLite OS layer used three functions in place of this
+** one:
+**
+** sqlite3OsOpenReadWrite();
+** sqlite3OsOpenReadOnly();
+** sqlite3OsOpenExclusive();
+**
+** These calls correspond to the following combinations of flags:
+**
+** ReadWrite() -> (READWRITE | CREATE)
+** ReadOnly() -> (READONLY)
+** OpenExclusive() -> (READWRITE | CREATE | EXCLUSIVE)
+**
+** The old OpenExclusive() accepted a boolean argument - "delFlag". If
+** true, the file was configured to be automatically deleted when the
+** file handle closed. To achieve the same effect using this new
+** interface, add the DELETEONCLOSE flag to those specified above for
+** OpenExclusive().
+*/
+static int unixOpen(
+ sqlite3_vfs *pVfs, /* The VFS for which this is the xOpen method */
+ const char *zPath, /* Pathname of file to be opened */
+ sqlite3_file *pFile, /* The file descriptor to be filled in */
+ int flags, /* Input flags to control the opening */
+ int *pOutFlags /* Output flags returned to SQLite core */
+){
+ unixFile *p = (unixFile *)pFile;
+ int fd = -1; /* File descriptor returned by open() */
+ int openFlags = 0; /* Flags to pass to open() */
+ int eType = flags&0xFFFFFF00; /* Type of file to open */
+ int noLock; /* True to omit locking primitives */
+ int rc = SQLITE_OK; /* Function Return Code */
+ int ctrlFlags = 0; /* UNIXFILE_* flags */
+
+ int isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE);
+ int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE);
+ int isCreate = (flags & SQLITE_OPEN_CREATE);
+ int isReadonly = (flags & SQLITE_OPEN_READONLY);
+ int isReadWrite = (flags & SQLITE_OPEN_READWRITE);
+#if SQLITE_ENABLE_LOCKING_STYLE
+ int isAutoProxy = (flags & SQLITE_OPEN_AUTOPROXY);
+#endif
+#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE
+ struct statfs fsInfo;
+#endif
+
+ /* If creating a master or main-file journal, this function will open
+ ** a file-descriptor on the directory too. The first time unixSync()
+ ** is called the directory file descriptor will be fsync()ed and close()d.
+ */
+ int syncDir = (isCreate && (
+ eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_MAIN_JOURNAL
+ || eType==SQLITE_OPEN_WAL
+ ));
+
+ /* If argument zPath is a NULL pointer, this function is required to open
+ ** a temporary file. Use this buffer to store the file name in.
+ */
+ char zTmpname[MAX_PATHNAME+2];
+ const char *zName = zPath;
+
+ /* Check the following statements are true:
+ **
+ ** (a) Exactly one of the READWRITE and READONLY flags must be set, and
+ ** (b) if CREATE is set, then READWRITE must also be set, and
+ ** (c) if EXCLUSIVE is set, then CREATE must also be set.
+ ** (d) if DELETEONCLOSE is set, then CREATE must also be set.
+ */
+ assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
+ assert(isCreate==0 || isReadWrite);
+ assert(isExclusive==0 || isCreate);
+ assert(isDelete==0 || isCreate);
+
+ /* The main DB, main journal, WAL file and master journal are never
+ ** automatically deleted. Nor are they ever temporary files. */
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
+
+ /* Assert that the upper layer has set one of the "file-type" flags. */
+ assert( eType==SQLITE_OPEN_MAIN_DB || eType==SQLITE_OPEN_TEMP_DB
+ || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL
+ || eType==SQLITE_OPEN_SUBJOURNAL || eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
+ );
+
+ /* Detect a pid change and reset the PRNG. There is a race condition
+ ** here such that two or more threads all trying to open databases at
+ ** the same instant might all reset the PRNG. But multiple resets
+ ** are harmless.
+ */
+ if( randomnessPid!=getpid() ){
+ randomnessPid = getpid();
+ sqlite3_randomness(0,0);
+ }
+
+ memset(p, 0, sizeof(unixFile));
+
+ if( eType==SQLITE_OPEN_MAIN_DB ){
+ UnixUnusedFd *pUnused;
+ pUnused = findReusableFd(zName, flags);
+ if( pUnused ){
+ fd = pUnused->fd;
+ }else{
+ pUnused = sqlite3_malloc(sizeof(*pUnused));
+ if( !pUnused ){
+ return SQLITE_NOMEM;
+ }
+ }
+ p->pUnused = pUnused;
+
+ /* Database filenames are double-zero terminated if they are not
+ ** URIs with parameters. Hence, they can always be passed into
+ ** sqlite3_uri_parameter(). */
+ assert( (flags & SQLITE_OPEN_URI) || zName[strlen(zName)+1]==0 );
+
+ }else if( !zName ){
+ /* If zName is NULL, the upper layer is requesting a temp file. */
+ assert(isDelete && !syncDir);
+ rc = unixGetTempname(MAX_PATHNAME+2, zTmpname);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ zName = zTmpname;
+
+ /* Generated temporary filenames are always double-zero terminated
+ ** for use by sqlite3_uri_parameter(). */
+ assert( zName[strlen(zName)+1]==0 );
+ }
+
+ /* Determine the value of the flags parameter passed to POSIX function
+ ** open(). These must be calculated even if open() is not called, as
+ ** they may be stored as part of the file handle and used by the
+ ** 'conch file' locking functions later on. */
+ if( isReadonly ) openFlags |= O_RDONLY;
+ if( isReadWrite ) openFlags |= O_RDWR;
+ if( isCreate ) openFlags |= O_CREAT;
+ if( isExclusive ) openFlags |= (O_EXCL|O_NOFOLLOW);
+ openFlags |= (O_LARGEFILE|O_BINARY);
+
+ if( fd<0 ){
+ mode_t openMode; /* Permissions to create file with */
+ uid_t uid; /* Userid for the file */
+ gid_t gid; /* Groupid for the file */
+ rc = findCreateFileMode(zName, flags, &openMode, &uid, &gid);
+ if( rc!=SQLITE_OK ){
+ assert( !p->pUnused );
+ assert( eType==SQLITE_OPEN_WAL || eType==SQLITE_OPEN_MAIN_JOURNAL );
+ return rc;
+ }
+ fd = robust_open(zName, openFlags, openMode);
+ OSTRACE(("OPENX %-3d %s 0%o\n", fd, zName, openFlags));
+ if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
+ /* Failed to open the file for read/write access. Try read-only. */
+ flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
+ openFlags &= ~(O_RDWR|O_CREAT);
+ flags |= SQLITE_OPEN_READONLY;
+ openFlags |= O_RDONLY;
+ isReadonly = 1;
+ fd = robust_open(zName, openFlags, openMode);
+ }
+ if( fd<0 ){
+ rc = unixLogError(SQLITE_CANTOPEN_BKPT, "open", zName);
+ goto open_finished;
+ }
+
+ /* If this process is running as root and if creating a new rollback
+ ** journal or WAL file, set the ownership of the journal or WAL to be
+ ** the same as the original database.
+ */
+ if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
+ osFchown(fd, uid, gid);
+ }
+ }
+ assert( fd>=0 );
+ if( pOutFlags ){
+ *pOutFlags = flags;
+ }
+
+ if( p->pUnused ){
+ p->pUnused->fd = fd;
+ p->pUnused->flags = flags;
+ }
+
+ if( isDelete ){
+#if OS_VXWORKS
+ zPath = zName;
+#else
+ osUnlink(zName);
+#endif
+ }
+#if SQLITE_ENABLE_LOCKING_STYLE
+ else{
+ p->openFlags = openFlags;
+ }
+#endif
+
+ noLock = eType!=SQLITE_OPEN_MAIN_DB;
+
+
+#if defined(__APPLE__) || SQLITE_ENABLE_LOCKING_STYLE
+ if( fstatfs(fd, &fsInfo) == -1 ){
+ ((unixFile*)pFile)->lastErrno = errno;
+ robust_close(p, fd, __LINE__);
+ return SQLITE_IOERR_ACCESS;
+ }
+ if (0 == strncmp("msdos", fsInfo.f_fstypename, 5)) {
+ ((unixFile*)pFile)->fsFlags |= SQLITE_FSFLAGS_IS_MSDOS;
+ }
+#endif
+
+ /* Set up appropriate ctrlFlags */
+ if( isDelete ) ctrlFlags |= UNIXFILE_DELETE;
+ if( isReadonly ) ctrlFlags |= UNIXFILE_RDONLY;
+ if( noLock ) ctrlFlags |= UNIXFILE_NOLOCK;
+ if( syncDir ) ctrlFlags |= UNIXFILE_DIRSYNC;
+ if( flags & SQLITE_OPEN_URI ) ctrlFlags |= UNIXFILE_URI;
+
+#if SQLITE_ENABLE_LOCKING_STYLE
+#if SQLITE_PREFER_PROXY_LOCKING
+ isAutoProxy = 1;
+#endif
+ if( isAutoProxy && (zPath!=NULL) && (!noLock) && pVfs->xOpen ){
+ char *envforce = getenv("SQLITE_FORCE_PROXY_LOCKING");
+ int useProxy = 0;
+
+ /* SQLITE_FORCE_PROXY_LOCKING==1 means force always use proxy, 0 means
+ ** never use proxy, NULL means use proxy for non-local files only. */
+ if( envforce!=NULL ){
+ useProxy = atoi(envforce)>0;
+ }else{
+ if( statfs(zPath, &fsInfo) == -1 ){
+ /* In theory, the close(fd) call is sub-optimal. If the file opened
+ ** with fd is a database file, and there are other connections open
+ ** on that file that are currently holding advisory locks on it,
+ ** then the call to close() will cancel those locks. In practice,
+ ** we're assuming that statfs() doesn't fail very often. At least
+ ** not while other file descriptors opened by the same process on
+ ** the same file are working. */
+ p->lastErrno = errno;
+ robust_close(p, fd, __LINE__);
+ rc = SQLITE_IOERR_ACCESS;
+ goto open_finished;
+ }
+ useProxy = !(fsInfo.f_flags&MNT_LOCAL);
+ }
+ if( useProxy ){
+ rc = fillInUnixFile(pVfs, fd, pFile, zPath, ctrlFlags);
+ if( rc==SQLITE_OK ){
+ rc = proxyTransformUnixFile((unixFile*)pFile, ":auto:");
+ if( rc!=SQLITE_OK ){
+ /* Use unixClose to clean up the resources added in fillInUnixFile
+ ** and clear all the structure's references. Specifically,
+ ** pFile->pMethods will be NULL so sqlite3OsClose will be a no-op
+ */
+ unixClose(pFile);
+ return rc;
+ }
+ }
+ goto open_finished;
+ }
+ }
+#endif
+
+ rc = fillInUnixFile(pVfs, fd, pFile, zPath, ctrlFlags);
+
+open_finished:
+ if( rc!=SQLITE_OK ){
+ sqlite3_free(p->pUnused);
+ }
+ return rc;
+}
+
+
+/*
+** Delete the file at zPath. If the dirSync argument is true, fsync()
+** the directory after deleting the file.
+*/
+static int unixDelete(
+ sqlite3_vfs *NotUsed, /* VFS containing this as the xDelete method */
+ const char *zPath, /* Name of file to be deleted */
+ int dirSync /* If true, fsync() directory after deleting file */
+){
+ int rc = SQLITE_OK;
+ UNUSED_PARAMETER(NotUsed);
+ SimulateIOError(return SQLITE_IOERR_DELETE);
+ if( osUnlink(zPath)==(-1) ){
+ if( errno==ENOENT ){
+ rc = SQLITE_IOERR_DELETE_NOENT;
+ }else{
+ rc = unixLogError(SQLITE_IOERR_DELETE, "unlink", zPath);
+ }
+ return rc;
+ }
+#ifndef SQLITE_DISABLE_DIRSYNC
+ if( (dirSync & 1)!=0 ){
+ int fd;
+ rc = osOpenDirectory(zPath, &fd);
+ if( rc==SQLITE_OK ){
+#if OS_VXWORKS
+ if( fsync(fd)==-1 )
+#else
+ if( fsync(fd) )
+#endif
+ {
+ rc = unixLogError(SQLITE_IOERR_DIR_FSYNC, "fsync", zPath);
+ }
+ robust_close(0, fd, __LINE__);
+ }else if( rc==SQLITE_CANTOPEN ){
+ rc = SQLITE_OK;
+ }
+ }
+#endif
+ return rc;
+}
+
+/*
+** Test the existence of or access permissions of file zPath. The
+** test performed depends on the value of flags:
+**
+** SQLITE_ACCESS_EXISTS: Return 1 if the file exists
+** SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
+** SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
+**
+** Otherwise return 0.
+*/
+static int unixAccess(
+ sqlite3_vfs *NotUsed, /* The VFS containing this xAccess method */
+ const char *zPath, /* Path of the file to examine */
+ int flags, /* What do we want to learn about the zPath file? */
+ int *pResOut /* Write result boolean here */
+){
+ int amode = 0;
+ UNUSED_PARAMETER(NotUsed);
+ SimulateIOError( return SQLITE_IOERR_ACCESS; );
+ switch( flags ){
+ case SQLITE_ACCESS_EXISTS:
+ amode = F_OK;
+ break;
+ case SQLITE_ACCESS_READWRITE:
+ amode = W_OK|R_OK;
+ break;
+ case SQLITE_ACCESS_READ:
+ amode = R_OK;
+ break;
+
+ default:
+ assert(!"Invalid flags argument");
+ }
+ *pResOut = (osAccess(zPath, amode)==0);
+ if( flags==SQLITE_ACCESS_EXISTS && *pResOut ){
+ struct stat buf;
+ if( 0==osStat(zPath, &buf) && buf.st_size==0 ){
+ *pResOut = 0;
+ }
+ }
+ return SQLITE_OK;
+}
+
+
+/*
+** Turn a relative pathname into a full pathname. The relative path
+** is stored as a nul-terminated string in the buffer pointed to by
+** zPath.
+**
+** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes
+** (in this case, MAX_PATHNAME bytes). The full-path is written to
+** this buffer before returning.
+*/
+static int unixFullPathname(
+ sqlite3_vfs *pVfs, /* Pointer to vfs object */
+ const char *zPath, /* Possibly relative input path */
+ int nOut, /* Size of output buffer in bytes */
+ char *zOut /* Output buffer */
+){
+
+ /* It's odd to simulate an io-error here, but really this is just
+ ** using the io-error infrastructure to test that SQLite handles this
+ ** function failing. This function could fail if, for example, the
+ ** current working directory has been unlinked.
+ */
+ SimulateIOError( return SQLITE_ERROR );
+
+ assert( pVfs->mxPathname==MAX_PATHNAME );
+ UNUSED_PARAMETER(pVfs);
+
+ zOut[nOut-1] = '\0';
+ if( zPath[0]=='/' ){
+ sqlite3_snprintf(nOut, zOut, "%s", zPath);
+ }else{
+ int nCwd;
+ if( osGetcwd(zOut, nOut-1)==0 ){
+ return unixLogError(SQLITE_CANTOPEN_BKPT, "getcwd", zPath);
+ }
+ nCwd = (int)strlen(zOut);
+ sqlite3_snprintf(nOut-nCwd, &zOut[nCwd], "/%s", zPath);
+ }
+ return SQLITE_OK;
+}
+
+
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+/*
+** Interfaces for opening a shared library, finding entry points
+** within the shared library, and closing the shared library.
+*/
+#include
+static void *unixDlOpen(sqlite3_vfs *NotUsed, const char *zFilename){
+ UNUSED_PARAMETER(NotUsed);
+ return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
+}
+
+/*
+** SQLite calls this function immediately after a call to unixDlSym() or
+** unixDlOpen() fails (returns a null pointer). If a more detailed error
+** message is available, it is written to zBufOut. If no error message
+** is available, zBufOut is left unmodified and SQLite uses a default
+** error message.
+*/
+static void unixDlError(sqlite3_vfs *NotUsed, int nBuf, char *zBufOut){
+ const char *zErr;
+ UNUSED_PARAMETER(NotUsed);
+ unixEnterMutex();
+ zErr = dlerror();
+ if( zErr ){
+ sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);
+ }
+ unixLeaveMutex();
+}
+static void (*unixDlSym(sqlite3_vfs *NotUsed, void *p, const char*zSym))(void){
+ /*
+ ** GCC with -pedantic-errors says that C90 does not allow a void* to be
+ ** cast into a pointer to a function. And yet the library dlsym() routine
+ ** returns a void* which is really a pointer to a function. So how do we
+ ** use dlsym() with -pedantic-errors?
+ **
+ ** Variable x below is defined to be a pointer to a function taking
+ ** parameters void* and const char* and returning a pointer to a function.
+ ** We initialize x by assigning it a pointer to the dlsym() function.
+ ** (That assignment requires a cast.) Then we call the function that
+ ** x points to.
+ **
+ ** This work-around is unlikely to work correctly on any system where
+ ** you really cannot cast a function pointer into void*. But then, on the
+ ** other hand, dlsym() will not work on such a system either, so we have
+ ** not really lost anything.
+ */
+ void (*(*x)(void*,const char*))(void);
+ UNUSED_PARAMETER(NotUsed);
+ x = (void(*(*)(void*,const char*))(void))dlsym;
+ return (*x)(p, zSym);
+}
+static void unixDlClose(sqlite3_vfs *NotUsed, void *pHandle){
+ UNUSED_PARAMETER(NotUsed);
+ dlclose(pHandle);
+}
+#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
+ #define unixDlOpen 0
+ #define unixDlError 0
+ #define unixDlSym 0
+ #define unixDlClose 0
+#endif
+
+/*
+** Write nBuf bytes of random data to the supplied buffer zBuf.
+*/
+static int unixRandomness(sqlite3_vfs *NotUsed, int nBuf, char *zBuf){
+ UNUSED_PARAMETER(NotUsed);
+ assert((size_t)nBuf>=(sizeof(time_t)+sizeof(int)));
+
+ /* We have to initialize zBuf to prevent valgrind from reporting
+ ** errors. The reports issued by valgrind are incorrect - we would
+ ** prefer that the randomness be increased by making use of the
+ ** uninitialized space in zBuf - but valgrind errors tend to worry
+ ** some users. Rather than argue, it seems easier just to initialize
+ ** the whole array and silence valgrind, even if that means less randomness
+ ** in the random seed.
+ **
+ ** When testing, initializing zBuf[] to zero is all we do. That means
+ ** that we always use the same random number sequence. This makes the
+ ** tests repeatable.
+ */
+ memset(zBuf, 0, nBuf);
+ randomnessPid = getpid();
+#if !defined(SQLITE_TEST)
+ {
+ int fd, got;
+ fd = robust_open("/dev/urandom", O_RDONLY, 0);
+ if( fd<0 ){
+ time_t t;
+ time(&t);
+ memcpy(zBuf, &t, sizeof(t));
+ memcpy(&zBuf[sizeof(t)], &randomnessPid, sizeof(randomnessPid));
+ assert( sizeof(t)+sizeof(randomnessPid)<=(size_t)nBuf );
+ nBuf = sizeof(t) + sizeof(randomnessPid);
+ }else{
+ do{ got = osRead(fd, zBuf, nBuf); }while( got<0 && errno==EINTR );
+ robust_close(0, fd, __LINE__);
+ }
+ }
+#endif
+ return nBuf;
+}
+
+
+/*
+** Sleep for a little while. Return the amount of time slept.
+** The argument is the number of microseconds we want to sleep.
+** The return value is the number of microseconds of sleep actually
+** requested from the underlying operating system, a number which
+** might be greater than or equal to the argument, but not less
+** than the argument.
+*/
+static int unixSleep(sqlite3_vfs *NotUsed, int microseconds){
+#if OS_VXWORKS
+ struct timespec sp;
+
+ sp.tv_sec = microseconds / 1000000;
+ sp.tv_nsec = (microseconds % 1000000) * 1000;
+ nanosleep(&sp, NULL);
+ UNUSED_PARAMETER(NotUsed);
+ return microseconds;
+#elif defined(HAVE_USLEEP) && HAVE_USLEEP
+ usleep(microseconds);
+ UNUSED_PARAMETER(NotUsed);
+ return microseconds;
+#else
+ int seconds = (microseconds+999999)/1000000;
+ sleep(seconds);
+ UNUSED_PARAMETER(NotUsed);
+ return seconds*1000000;
+#endif
+}
+
+/*
+** The following variable, if set to a non-zero value, is interpreted as
+** the number of seconds since 1970 and is used to set the result of
+** sqlite3OsCurrentTime() during testing.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_current_time = 0; /* Fake system time in seconds since 1970. */
+#endif
+
+/*
+** Find the current time (in Universal Coordinated Time). Write into *piNow
+** the current time and date as a Julian Day number times 86_400_000. In
+** other words, write into *piNow the number of milliseconds since the Julian
+** epoch of noon in Greenwich on November 24, 4714 B.C according to the
+** proleptic Gregorian calendar.
+**
+** On success, return SQLITE_OK. Return SQLITE_ERROR if the time and date
+** cannot be found.
+*/
+static int unixCurrentTimeInt64(sqlite3_vfs *NotUsed, sqlite3_int64 *piNow){
+ static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
+ int rc = SQLITE_OK;
+#if defined(NO_GETTOD)
+ time_t t;
+ time(&t);
+ *piNow = ((sqlite3_int64)t)*1000 + unixEpoch;
+#elif OS_VXWORKS
+ struct timespec sNow;
+ clock_gettime(CLOCK_REALTIME, &sNow);
+ *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_nsec/1000000;
+#else
+ struct timeval sNow;
+ if( gettimeofday(&sNow, 0)==0 ){
+ *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_usec/1000;
+ }else{
+ rc = SQLITE_ERROR;
+ }
+#endif
+
+#ifdef SQLITE_TEST
+ if( sqlite3_current_time ){
+ *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
+ }
+#endif
+ UNUSED_PARAMETER(NotUsed);
+ return rc;
+}
+
+/*
+** Find the current time (in Universal Coordinated Time). Write the
+** current time and date as a Julian Day number into *prNow and
+** return 0. Return 1 if the time and date cannot be found.
+*/
+static int unixCurrentTime(sqlite3_vfs *NotUsed, double *prNow){
+ sqlite3_int64 i = 0;
+ int rc;
+ UNUSED_PARAMETER(NotUsed);
+ rc = unixCurrentTimeInt64(0, &i);
+ *prNow = i/86400000.0;
+ return rc;
+}
+
+/*
+** We added the xGetLastError() method with the intention of providing
+** better low-level error messages when operating-system problems come up
+** during SQLite operation. But so far, none of that has been implemented
+** in the core. So this routine is never called. For now, it is merely
+** a place-holder.
+*/
+static int unixGetLastError(sqlite3_vfs *NotUsed, int NotUsed2, char *NotUsed3){
+ UNUSED_PARAMETER(NotUsed);
+ UNUSED_PARAMETER(NotUsed2);
+ UNUSED_PARAMETER(NotUsed3);
+ return 0;
+}
+
+
+/*
+************************ End of sqlite3_vfs methods ***************************
+******************************************************************************/
+
+/******************************************************************************
+************************** Begin Proxy Locking ********************************
+**
+** Proxy locking is a "uber-locking-method" in this sense: It uses the
+** other locking methods on secondary lock files. Proxy locking is a
+** meta-layer over top of the primitive locking implemented above. For
+** this reason, the division that implements of proxy locking is deferred
+** until late in the file (here) after all of the other I/O methods have
+** been defined - so that the primitive locking methods are available
+** as services to help with the implementation of proxy locking.
+**
+****
+**
+** The default locking schemes in SQLite use byte-range locks on the
+** database file to coordinate safe, concurrent access by multiple readers
+** and writers [http://sqlite.org/lockingv3.html]. The five file locking
+** states (UNLOCKED, PENDING, SHARED, RESERVED, EXCLUSIVE) are implemented
+** as POSIX read & write locks over fixed set of locations (via fsctl),
+** on AFP and SMB only exclusive byte-range locks are available via fsctl
+** with _IOWR('z', 23, struct ByteRangeLockPB2) to track the same 5 states.
+** To simulate a F_RDLCK on the shared range, on AFP a randomly selected
+** address in the shared range is taken for a SHARED lock, the entire
+** shared range is taken for an EXCLUSIVE lock):
+**
+** PENDING_BYTE 0x40000000
+** RESERVED_BYTE 0x40000001
+** SHARED_RANGE 0x40000002 -> 0x40000200
+**
+** This works well on the local file system, but shows a nearly 100x
+** slowdown in read performance on AFP because the AFP client disables
+** the read cache when byte-range locks are present. Enabling the read
+** cache exposes a cache coherency problem that is present on all OS X
+** supported network file systems. NFS and AFP both observe the
+** close-to-open semantics for ensuring cache coherency
+** [http://nfs.sourceforge.net/#faq_a8], which does not effectively
+** address the requirements for concurrent database access by multiple
+** readers and writers
+** [http://www.nabble.com/SQLite-on-NFS-cache-coherency-td15655701.html].
+**
+** To address the performance and cache coherency issues, proxy file locking
+** changes the way database access is controlled by limiting access to a
+** single host at a time and moving file locks off of the database file
+** and onto a proxy file on the local file system.
+**
+**
+** Using proxy locks
+** -----------------
+**
+** C APIs
+**
+** sqlite3_file_control(db, dbname, SQLITE_SET_LOCKPROXYFILE,
+** | ":auto:");
+** sqlite3_file_control(db, dbname, SQLITE_GET_LOCKPROXYFILE, &);
+**
+**
+** SQL pragmas
+**
+** PRAGMA [database.]lock_proxy_file= | :auto:
+** PRAGMA [database.]lock_proxy_file
+**
+** Specifying ":auto:" means that if there is a conch file with a matching
+** host ID in it, the proxy path in the conch file will be used, otherwise
+** a proxy path based on the user's temp dir
+** (via confstr(_CS_DARWIN_USER_TEMP_DIR,...)) will be used and the
+** actual proxy file name is generated from the name and path of the
+** database file. For example:
+**
+** For database path "/Users/me/foo.db"
+** The lock path will be "/sqliteplocks/_Users_me_foo.db:auto:")
+**
+** Once a lock proxy is configured for a database connection, it can not
+** be removed, however it may be switched to a different proxy path via
+** the above APIs (assuming the conch file is not being held by another
+** connection or process).
+**
+**
+** How proxy locking works
+** -----------------------
+**
+** Proxy file locking relies primarily on two new supporting files:
+**
+** * conch file to limit access to the database file to a single host
+** at a time
+**
+** * proxy file to act as a proxy for the advisory locks normally
+** taken on the database
+**
+** The conch file - to use a proxy file, sqlite must first "hold the conch"
+** by taking an sqlite-style shared lock on the conch file, reading the
+** contents and comparing the host's unique host ID (see below) and lock
+** proxy path against the values stored in the conch. The conch file is
+** stored in the same directory as the database file and the file name
+** is patterned after the database file name as ".-conch".
+** If the conch file does not exist, or it's contents do not match the
+** host ID and/or proxy path, then the lock is escalated to an exclusive
+** lock and the conch file contents is updated with the host ID and proxy
+** path and the lock is downgraded to a shared lock again. If the conch
+** is held by another process (with a shared lock), the exclusive lock
+** will fail and SQLITE_BUSY is returned.
+**
+** The proxy file - a single-byte file used for all advisory file locks
+** normally taken on the database file. This allows for safe sharing
+** of the database file for multiple readers and writers on the same
+** host (the conch ensures that they all use the same local lock file).
+**
+** Requesting the lock proxy does not immediately take the conch, it is
+** only taken when the first request to lock database file is made.
+** This matches the semantics of the traditional locking behavior, where
+** opening a connection to a database file does not take a lock on it.
+** The shared lock and an open file descriptor are maintained until
+** the connection to the database is closed.
+**
+** The proxy file and the lock file are never deleted so they only need
+** to be created the first time they are used.
+**
+** Configuration options
+** ---------------------
+**
+** SQLITE_PREFER_PROXY_LOCKING
+**
+** Database files accessed on non-local file systems are
+** automatically configured for proxy locking, lock files are
+** named automatically using the same logic as
+** PRAGMA lock_proxy_file=":auto:"
+**
+** SQLITE_PROXY_DEBUG
+**
+** Enables the logging of error messages during host id file
+** retrieval and creation
+**
+** LOCKPROXYDIR
+**
+** Overrides the default directory used for lock proxy files that
+** are named automatically via the ":auto:" setting
+**
+** SQLITE_DEFAULT_PROXYDIR_PERMISSIONS
+**
+** Permissions to use when creating a directory for storing the
+** lock proxy files, only used when LOCKPROXYDIR is not set.
+**
+**
+** As mentioned above, when compiled with SQLITE_PREFER_PROXY_LOCKING,
+** setting the environment variable SQLITE_FORCE_PROXY_LOCKING to 1 will
+** force proxy locking to be used for every database file opened, and 0
+** will force automatic proxy locking to be disabled for all database
+** files (explicity calling the SQLITE_SET_LOCKPROXYFILE pragma or
+** sqlite_file_control API is not affected by SQLITE_FORCE_PROXY_LOCKING).
+*/
+
+/*
+** Proxy locking is only available on MacOSX
+*/
+#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
+
+/*
+** The proxyLockingContext has the path and file structures for the remote
+** and local proxy files in it
+*/
+typedef struct proxyLockingContext proxyLockingContext;
+struct proxyLockingContext {
+ unixFile *conchFile; /* Open conch file */
+ char *conchFilePath; /* Name of the conch file */
+ unixFile *lockProxy; /* Open proxy lock file */
+ char *lockProxyPath; /* Name of the proxy lock file */
+ char *dbPath; /* Name of the open file */
+ int conchHeld; /* 1 if the conch is held, -1 if lockless */
+ void *oldLockingContext; /* Original lockingcontext to restore on close */
+ sqlite3_io_methods const *pOldMethod; /* Original I/O methods for close */
+};
+
+/*
+** The proxy lock file path for the database at dbPath is written into lPath,
+** which must point to valid, writable memory large enough for a maxLen length
+** file path.
+*/
+static int proxyGetLockPath(const char *dbPath, char *lPath, size_t maxLen){
+ int len;
+ int dbLen;
+ int i;
+
+#ifdef LOCKPROXYDIR
+ len = strlcpy(lPath, LOCKPROXYDIR, maxLen);
+#else
+# ifdef _CS_DARWIN_USER_TEMP_DIR
+ {
+ if( !confstr(_CS_DARWIN_USER_TEMP_DIR, lPath, maxLen) ){
+ OSTRACE(("GETLOCKPATH failed %s errno=%d pid=%d\n",
+ lPath, errno, getpid()));
+ return SQLITE_IOERR_LOCK;
+ }
+ len = strlcat(lPath, "sqliteplocks", maxLen);
+ }
+# else
+ len = strlcpy(lPath, "/tmp/", maxLen);
+# endif
+#endif
+
+ if( lPath[len-1]!='/' ){
+ len = strlcat(lPath, "/", maxLen);
+ }
+
+ /* transform the db path to a unique cache name */
+ dbLen = (int)strlen(dbPath);
+ for( i=0; i 0) ){
+ /* only mkdir if leaf dir != "." or "/" or ".." */
+ if( i-start>2 || (i-start==1 && buf[start] != '.' && buf[start] != '/')
+ || (i-start==2 && buf[start] != '.' && buf[start+1] != '.') ){
+ buf[i]='\0';
+ if( osMkdir(buf, SQLITE_DEFAULT_PROXYDIR_PERMISSIONS) ){
+ int err=errno;
+ if( err!=EEXIST ) {
+ OSTRACE(("CREATELOCKPATH FAILED creating %s, "
+ "'%s' proxy lock path=%s pid=%d\n",
+ buf, strerror(err), lockPath, getpid()));
+ return err;
+ }
+ }
+ }
+ start=i+1;
+ }
+ buf[i] = lockPath[i];
+ }
+ OSTRACE(("CREATELOCKPATH proxy lock path=%s pid=%d\n", lockPath, getpid()));
+ return 0;
+}
+
+/*
+** Create a new VFS file descriptor (stored in memory obtained from
+** sqlite3_malloc) and open the file named "path" in the file descriptor.
+**
+** The caller is responsible not only for closing the file descriptor
+** but also for freeing the memory associated with the file descriptor.
+*/
+static int proxyCreateUnixFile(
+ const char *path, /* path for the new unixFile */
+ unixFile **ppFile, /* unixFile created and returned by ref */
+ int islockfile /* if non zero missing dirs will be created */
+) {
+ int fd = -1;
+ unixFile *pNew;
+ int rc = SQLITE_OK;
+ int openFlags = O_RDWR | O_CREAT;
+ sqlite3_vfs dummyVfs;
+ int terrno = 0;
+ UnixUnusedFd *pUnused = NULL;
+
+ /* 1. first try to open/create the file
+ ** 2. if that fails, and this is a lock file (not-conch), try creating
+ ** the parent directories and then try again.
+ ** 3. if that fails, try to open the file read-only
+ ** otherwise return BUSY (if lock file) or CANTOPEN for the conch file
+ */
+ pUnused = findReusableFd(path, openFlags);
+ if( pUnused ){
+ fd = pUnused->fd;
+ }else{
+ pUnused = sqlite3_malloc(sizeof(*pUnused));
+ if( !pUnused ){
+ return SQLITE_NOMEM;
+ }
+ }
+ if( fd<0 ){
+ fd = robust_open(path, openFlags, 0);
+ terrno = errno;
+ if( fd<0 && errno==ENOENT && islockfile ){
+ if( proxyCreateLockPath(path) == SQLITE_OK ){
+ fd = robust_open(path, openFlags, 0);
+ }
+ }
+ }
+ if( fd<0 ){
+ openFlags = O_RDONLY;
+ fd = robust_open(path, openFlags, 0);
+ terrno = errno;
+ }
+ if( fd<0 ){
+ if( islockfile ){
+ return SQLITE_BUSY;
+ }
+ switch (terrno) {
+ case EACCES:
+ return SQLITE_PERM;
+ case EIO:
+ return SQLITE_IOERR_LOCK; /* even though it is the conch */
+ default:
+ return SQLITE_CANTOPEN_BKPT;
+ }
+ }
+
+ pNew = (unixFile *)sqlite3_malloc(sizeof(*pNew));
+ if( pNew==NULL ){
+ rc = SQLITE_NOMEM;
+ goto end_create_proxy;
+ }
+ memset(pNew, 0, sizeof(unixFile));
+ pNew->openFlags = openFlags;
+ memset(&dummyVfs, 0, sizeof(dummyVfs));
+ dummyVfs.pAppData = (void*)&autolockIoFinder;
+ dummyVfs.zName = "dummy";
+ pUnused->fd = fd;
+ pUnused->flags = openFlags;
+ pNew->pUnused = pUnused;
+
+ rc = fillInUnixFile(&dummyVfs, fd, (sqlite3_file*)pNew, path, 0);
+ if( rc==SQLITE_OK ){
+ *ppFile = pNew;
+ return SQLITE_OK;
+ }
+end_create_proxy:
+ robust_close(pNew, fd, __LINE__);
+ sqlite3_free(pNew);
+ sqlite3_free(pUnused);
+ return rc;
+}
+
+#ifdef SQLITE_TEST
+/* simulate multiple hosts by creating unique hostid file paths */
+SQLITE_API int sqlite3_hostid_num = 0;
+#endif
+
+#define PROXY_HOSTIDLEN 16 /* conch file host id length */
+
+/* Not always defined in the headers as it ought to be */
+extern int gethostuuid(uuid_t id, const struct timespec *wait);
+
+/* get the host ID via gethostuuid(), pHostID must point to PROXY_HOSTIDLEN
+** bytes of writable memory.
+*/
+static int proxyGetHostID(unsigned char *pHostID, int *pError){
+ assert(PROXY_HOSTIDLEN == sizeof(uuid_t));
+ memset(pHostID, 0, PROXY_HOSTIDLEN);
+#if defined(__MAX_OS_X_VERSION_MIN_REQUIRED)\
+ && __MAC_OS_X_VERSION_MIN_REQUIRED<1050
+ {
+ static const struct timespec timeout = {1, 0}; /* 1 sec timeout */
+ if( gethostuuid(pHostID, &timeout) ){
+ int err = errno;
+ if( pError ){
+ *pError = err;
+ }
+ return SQLITE_IOERR;
+ }
+ }
+#else
+ UNUSED_PARAMETER(pError);
+#endif
+#ifdef SQLITE_TEST
+ /* simulate multiple hosts by creating unique hostid file paths */
+ if( sqlite3_hostid_num != 0){
+ pHostID[0] = (char)(pHostID[0] + (char)(sqlite3_hostid_num & 0xFF));
+ }
+#endif
+
+ return SQLITE_OK;
+}
+
+/* The conch file contains the header, host id and lock file path
+ */
+#define PROXY_CONCHVERSION 2 /* 1-byte header, 16-byte host id, path */
+#define PROXY_HEADERLEN 1 /* conch file header length */
+#define PROXY_PATHINDEX (PROXY_HEADERLEN+PROXY_HOSTIDLEN)
+#define PROXY_MAXCONCHLEN (PROXY_HEADERLEN+PROXY_HOSTIDLEN+MAXPATHLEN)
+
+/*
+** Takes an open conch file, copies the contents to a new path and then moves
+** it back. The newly created file's file descriptor is assigned to the
+** conch file structure and finally the original conch file descriptor is
+** closed. Returns zero if successful.
+*/
+static int proxyBreakConchLock(unixFile *pFile, uuid_t myHostID){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ unixFile *conchFile = pCtx->conchFile;
+ char tPath[MAXPATHLEN];
+ char buf[PROXY_MAXCONCHLEN];
+ char *cPath = pCtx->conchFilePath;
+ size_t readLen = 0;
+ size_t pathLen = 0;
+ char errmsg[64] = "";
+ int fd = -1;
+ int rc = -1;
+ UNUSED_PARAMETER(myHostID);
+
+ /* create a new path by replace the trailing '-conch' with '-break' */
+ pathLen = strlcpy(tPath, cPath, MAXPATHLEN);
+ if( pathLen>MAXPATHLEN || pathLen<6 ||
+ (strlcpy(&tPath[pathLen-5], "break", 6) != 5) ){
+ sqlite3_snprintf(sizeof(errmsg),errmsg,"path error (len %d)",(int)pathLen);
+ goto end_breaklock;
+ }
+ /* read the conch content */
+ readLen = osPread(conchFile->h, buf, PROXY_MAXCONCHLEN, 0);
+ if( readLenh, __LINE__);
+ conchFile->h = fd;
+ conchFile->openFlags = O_RDWR | O_CREAT;
+
+end_breaklock:
+ if( rc ){
+ if( fd>=0 ){
+ osUnlink(tPath);
+ robust_close(pFile, fd, __LINE__);
+ }
+ fprintf(stderr, "failed to break stale lock on %s, %s\n", cPath, errmsg);
+ }
+ return rc;
+}
+
+/* Take the requested lock on the conch file and break a stale lock if the
+** host id matches.
+*/
+static int proxyConchLock(unixFile *pFile, uuid_t myHostID, int lockType){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ unixFile *conchFile = pCtx->conchFile;
+ int rc = SQLITE_OK;
+ int nTries = 0;
+ struct timespec conchModTime;
+
+ memset(&conchModTime, 0, sizeof(conchModTime));
+ do {
+ rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, lockType);
+ nTries ++;
+ if( rc==SQLITE_BUSY ){
+ /* If the lock failed (busy):
+ * 1st try: get the mod time of the conch, wait 0.5s and try again.
+ * 2nd try: fail if the mod time changed or host id is different, wait
+ * 10 sec and try again
+ * 3rd try: break the lock unless the mod time has changed.
+ */
+ struct stat buf;
+ if( osFstat(conchFile->h, &buf) ){
+ pFile->lastErrno = errno;
+ return SQLITE_IOERR_LOCK;
+ }
+
+ if( nTries==1 ){
+ conchModTime = buf.st_mtimespec;
+ usleep(500000); /* wait 0.5 sec and try the lock again*/
+ continue;
+ }
+
+ assert( nTries>1 );
+ if( conchModTime.tv_sec != buf.st_mtimespec.tv_sec ||
+ conchModTime.tv_nsec != buf.st_mtimespec.tv_nsec ){
+ return SQLITE_BUSY;
+ }
+
+ if( nTries==2 ){
+ char tBuf[PROXY_MAXCONCHLEN];
+ int len = osPread(conchFile->h, tBuf, PROXY_MAXCONCHLEN, 0);
+ if( len<0 ){
+ pFile->lastErrno = errno;
+ return SQLITE_IOERR_LOCK;
+ }
+ if( len>PROXY_PATHINDEX && tBuf[0]==(char)PROXY_CONCHVERSION){
+ /* don't break the lock if the host id doesn't match */
+ if( 0!=memcmp(&tBuf[PROXY_HEADERLEN], myHostID, PROXY_HOSTIDLEN) ){
+ return SQLITE_BUSY;
+ }
+ }else{
+ /* don't break the lock on short read or a version mismatch */
+ return SQLITE_BUSY;
+ }
+ usleep(10000000); /* wait 10 sec and try the lock again */
+ continue;
+ }
+
+ assert( nTries==3 );
+ if( 0==proxyBreakConchLock(pFile, myHostID) ){
+ rc = SQLITE_OK;
+ if( lockType==EXCLUSIVE_LOCK ){
+ rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, SHARED_LOCK);
+ }
+ if( !rc ){
+ rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, lockType);
+ }
+ }
+ }
+ } while( rc==SQLITE_BUSY && nTries<3 );
+
+ return rc;
+}
+
+/* Takes the conch by taking a shared lock and read the contents conch, if
+** lockPath is non-NULL, the host ID and lock file path must match. A NULL
+** lockPath means that the lockPath in the conch file will be used if the
+** host IDs match, or a new lock path will be generated automatically
+** and written to the conch file.
+*/
+static int proxyTakeConch(unixFile *pFile){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+
+ if( pCtx->conchHeld!=0 ){
+ return SQLITE_OK;
+ }else{
+ unixFile *conchFile = pCtx->conchFile;
+ uuid_t myHostID;
+ int pError = 0;
+ char readBuf[PROXY_MAXCONCHLEN];
+ char lockPath[MAXPATHLEN];
+ char *tempLockPath = NULL;
+ int rc = SQLITE_OK;
+ int createConch = 0;
+ int hostIdMatch = 0;
+ int readLen = 0;
+ int tryOldLockPath = 0;
+ int forceNewLockPath = 0;
+
+ OSTRACE(("TAKECONCH %d for %s pid=%d\n", conchFile->h,
+ (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"), getpid()));
+
+ rc = proxyGetHostID(myHostID, &pError);
+ if( (rc&0xff)==SQLITE_IOERR ){
+ pFile->lastErrno = pError;
+ goto end_takeconch;
+ }
+ rc = proxyConchLock(pFile, myHostID, SHARED_LOCK);
+ if( rc!=SQLITE_OK ){
+ goto end_takeconch;
+ }
+ /* read the existing conch file */
+ readLen = seekAndRead((unixFile*)conchFile, 0, readBuf, PROXY_MAXCONCHLEN);
+ if( readLen<0 ){
+ /* I/O error: lastErrno set by seekAndRead */
+ pFile->lastErrno = conchFile->lastErrno;
+ rc = SQLITE_IOERR_READ;
+ goto end_takeconch;
+ }else if( readLen<=(PROXY_HEADERLEN+PROXY_HOSTIDLEN) ||
+ readBuf[0]!=(char)PROXY_CONCHVERSION ){
+ /* a short read or version format mismatch means we need to create a new
+ ** conch file.
+ */
+ createConch = 1;
+ }
+ /* if the host id matches and the lock path already exists in the conch
+ ** we'll try to use the path there, if we can't open that path, we'll
+ ** retry with a new auto-generated path
+ */
+ do { /* in case we need to try again for an :auto: named lock file */
+
+ if( !createConch && !forceNewLockPath ){
+ hostIdMatch = !memcmp(&readBuf[PROXY_HEADERLEN], myHostID,
+ PROXY_HOSTIDLEN);
+ /* if the conch has data compare the contents */
+ if( !pCtx->lockProxyPath ){
+ /* for auto-named local lock file, just check the host ID and we'll
+ ** use the local lock file path that's already in there
+ */
+ if( hostIdMatch ){
+ size_t pathLen = (readLen - PROXY_PATHINDEX);
+
+ if( pathLen>=MAXPATHLEN ){
+ pathLen=MAXPATHLEN-1;
+ }
+ memcpy(lockPath, &readBuf[PROXY_PATHINDEX], pathLen);
+ lockPath[pathLen] = 0;
+ tempLockPath = lockPath;
+ tryOldLockPath = 1;
+ /* create a copy of the lock path if the conch is taken */
+ goto end_takeconch;
+ }
+ }else if( hostIdMatch
+ && !strncmp(pCtx->lockProxyPath, &readBuf[PROXY_PATHINDEX],
+ readLen-PROXY_PATHINDEX)
+ ){
+ /* conch host and lock path match */
+ goto end_takeconch;
+ }
+ }
+
+ /* if the conch isn't writable and doesn't match, we can't take it */
+ if( (conchFile->openFlags&O_RDWR) == 0 ){
+ rc = SQLITE_BUSY;
+ goto end_takeconch;
+ }
+
+ /* either the conch didn't match or we need to create a new one */
+ if( !pCtx->lockProxyPath ){
+ proxyGetLockPath(pCtx->dbPath, lockPath, MAXPATHLEN);
+ tempLockPath = lockPath;
+ /* create a copy of the lock path _only_ if the conch is taken */
+ }
+
+ /* update conch with host and path (this will fail if other process
+ ** has a shared lock already), if the host id matches, use the big
+ ** stick.
+ */
+ futimes(conchFile->h, NULL);
+ if( hostIdMatch && !createConch ){
+ if( conchFile->pInode && conchFile->pInode->nShared>1 ){
+ /* We are trying for an exclusive lock but another thread in this
+ ** same process is still holding a shared lock. */
+ rc = SQLITE_BUSY;
+ } else {
+ rc = proxyConchLock(pFile, myHostID, EXCLUSIVE_LOCK);
+ }
+ }else{
+ rc = conchFile->pMethod->xLock((sqlite3_file*)conchFile, EXCLUSIVE_LOCK);
+ }
+ if( rc==SQLITE_OK ){
+ char writeBuffer[PROXY_MAXCONCHLEN];
+ int writeSize = 0;
+
+ writeBuffer[0] = (char)PROXY_CONCHVERSION;
+ memcpy(&writeBuffer[PROXY_HEADERLEN], myHostID, PROXY_HOSTIDLEN);
+ if( pCtx->lockProxyPath!=NULL ){
+ strlcpy(&writeBuffer[PROXY_PATHINDEX], pCtx->lockProxyPath, MAXPATHLEN);
+ }else{
+ strlcpy(&writeBuffer[PROXY_PATHINDEX], tempLockPath, MAXPATHLEN);
+ }
+ writeSize = PROXY_PATHINDEX + strlen(&writeBuffer[PROXY_PATHINDEX]);
+ robust_ftruncate(conchFile->h, writeSize);
+ rc = unixWrite((sqlite3_file *)conchFile, writeBuffer, writeSize, 0);
+ fsync(conchFile->h);
+ /* If we created a new conch file (not just updated the contents of a
+ ** valid conch file), try to match the permissions of the database
+ */
+ if( rc==SQLITE_OK && createConch ){
+ struct stat buf;
+ int err = osFstat(pFile->h, &buf);
+ if( err==0 ){
+ mode_t cmode = buf.st_mode&(S_IRUSR|S_IWUSR | S_IRGRP|S_IWGRP |
+ S_IROTH|S_IWOTH);
+ /* try to match the database file R/W permissions, ignore failure */
+#ifndef SQLITE_PROXY_DEBUG
+ osFchmod(conchFile->h, cmode);
+#else
+ do{
+ rc = osFchmod(conchFile->h, cmode);
+ }while( rc==(-1) && errno==EINTR );
+ if( rc!=0 ){
+ int code = errno;
+ fprintf(stderr, "fchmod %o FAILED with %d %s\n",
+ cmode, code, strerror(code));
+ } else {
+ fprintf(stderr, "fchmod %o SUCCEDED\n",cmode);
+ }
+ }else{
+ int code = errno;
+ fprintf(stderr, "STAT FAILED[%d] with %d %s\n",
+ err, code, strerror(code));
+#endif
+ }
+ }
+ }
+ conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, SHARED_LOCK);
+
+ end_takeconch:
+ OSTRACE(("TRANSPROXY: CLOSE %d\n", pFile->h));
+ if( rc==SQLITE_OK && pFile->openFlags ){
+ int fd;
+ if( pFile->h>=0 ){
+ robust_close(pFile, pFile->h, __LINE__);
+ }
+ pFile->h = -1;
+ fd = robust_open(pCtx->dbPath, pFile->openFlags, 0);
+ OSTRACE(("TRANSPROXY: OPEN %d\n", fd));
+ if( fd>=0 ){
+ pFile->h = fd;
+ }else{
+ rc=SQLITE_CANTOPEN_BKPT; /* SQLITE_BUSY? proxyTakeConch called
+ during locking */
+ }
+ }
+ if( rc==SQLITE_OK && !pCtx->lockProxy ){
+ char *path = tempLockPath ? tempLockPath : pCtx->lockProxyPath;
+ rc = proxyCreateUnixFile(path, &pCtx->lockProxy, 1);
+ if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM && tryOldLockPath ){
+ /* we couldn't create the proxy lock file with the old lock file path
+ ** so try again via auto-naming
+ */
+ forceNewLockPath = 1;
+ tryOldLockPath = 0;
+ continue; /* go back to the do {} while start point, try again */
+ }
+ }
+ if( rc==SQLITE_OK ){
+ /* Need to make a copy of path if we extracted the value
+ ** from the conch file or the path was allocated on the stack
+ */
+ if( tempLockPath ){
+ pCtx->lockProxyPath = sqlite3DbStrDup(0, tempLockPath);
+ if( !pCtx->lockProxyPath ){
+ rc = SQLITE_NOMEM;
+ }
+ }
+ }
+ if( rc==SQLITE_OK ){
+ pCtx->conchHeld = 1;
+
+ if( pCtx->lockProxy->pMethod == &afpIoMethods ){
+ afpLockingContext *afpCtx;
+ afpCtx = (afpLockingContext *)pCtx->lockProxy->lockingContext;
+ afpCtx->dbPath = pCtx->lockProxyPath;
+ }
+ } else {
+ conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
+ }
+ OSTRACE(("TAKECONCH %d %s\n", conchFile->h,
+ rc==SQLITE_OK?"ok":"failed"));
+ return rc;
+ } while (1); /* in case we need to retry the :auto: lock file -
+ ** we should never get here except via the 'continue' call. */
+ }
+}
+
+/*
+** If pFile holds a lock on a conch file, then release that lock.
+*/
+static int proxyReleaseConch(unixFile *pFile){
+ int rc = SQLITE_OK; /* Subroutine return code */
+ proxyLockingContext *pCtx; /* The locking context for the proxy lock */
+ unixFile *conchFile; /* Name of the conch file */
+
+ pCtx = (proxyLockingContext *)pFile->lockingContext;
+ conchFile = pCtx->conchFile;
+ OSTRACE(("RELEASECONCH %d for %s pid=%d\n", conchFile->h,
+ (pCtx->lockProxyPath ? pCtx->lockProxyPath : ":auto:"),
+ getpid()));
+ if( pCtx->conchHeld>0 ){
+ rc = conchFile->pMethod->xUnlock((sqlite3_file*)conchFile, NO_LOCK);
+ }
+ pCtx->conchHeld = 0;
+ OSTRACE(("RELEASECONCH %d %s\n", conchFile->h,
+ (rc==SQLITE_OK ? "ok" : "failed")));
+ return rc;
+}
+
+/*
+** Given the name of a database file, compute the name of its conch file.
+** Store the conch filename in memory obtained from sqlite3_malloc().
+** Make *pConchPath point to the new name. Return SQLITE_OK on success
+** or SQLITE_NOMEM if unable to obtain memory.
+**
+** The caller is responsible for ensuring that the allocated memory
+** space is eventually freed.
+**
+** *pConchPath is set to NULL if a memory allocation error occurs.
+*/
+static int proxyCreateConchPathname(char *dbPath, char **pConchPath){
+ int i; /* Loop counter */
+ int len = (int)strlen(dbPath); /* Length of database filename - dbPath */
+ char *conchPath; /* buffer in which to construct conch name */
+
+ /* Allocate space for the conch filename and initialize the name to
+ ** the name of the original database file. */
+ *pConchPath = conchPath = (char *)sqlite3_malloc(len + 8);
+ if( conchPath==0 ){
+ return SQLITE_NOMEM;
+ }
+ memcpy(conchPath, dbPath, len+1);
+
+ /* now insert a "." before the last / character */
+ for( i=(len-1); i>=0; i-- ){
+ if( conchPath[i]=='/' ){
+ i++;
+ break;
+ }
+ }
+ conchPath[i]='.';
+ while ( ilockingContext;
+ char *oldPath = pCtx->lockProxyPath;
+ int rc = SQLITE_OK;
+
+ if( pFile->eFileLock!=NO_LOCK ){
+ return SQLITE_BUSY;
+ }
+
+ /* nothing to do if the path is NULL, :auto: or matches the existing path */
+ if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ||
+ (oldPath && !strncmp(oldPath, path, MAXPATHLEN)) ){
+ return SQLITE_OK;
+ }else{
+ unixFile *lockProxy = pCtx->lockProxy;
+ pCtx->lockProxy=NULL;
+ pCtx->conchHeld = 0;
+ if( lockProxy!=NULL ){
+ rc=lockProxy->pMethod->xClose((sqlite3_file *)lockProxy);
+ if( rc ) return rc;
+ sqlite3_free(lockProxy);
+ }
+ sqlite3_free(oldPath);
+ pCtx->lockProxyPath = sqlite3DbStrDup(0, path);
+ }
+
+ return rc;
+}
+
+/*
+** pFile is a file that has been opened by a prior xOpen call. dbPath
+** is a string buffer at least MAXPATHLEN+1 characters in size.
+**
+** This routine find the filename associated with pFile and writes it
+** int dbPath.
+*/
+static int proxyGetDbPathForUnixFile(unixFile *pFile, char *dbPath){
+#if defined(__APPLE__)
+ if( pFile->pMethod == &afpIoMethods ){
+ /* afp style keeps a reference to the db path in the filePath field
+ ** of the struct */
+ assert( (int)strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
+ strlcpy(dbPath, ((afpLockingContext *)pFile->lockingContext)->dbPath, MAXPATHLEN);
+ } else
+#endif
+ if( pFile->pMethod == &dotlockIoMethods ){
+ /* dot lock style uses the locking context to store the dot lock
+ ** file path */
+ int len = strlen((char *)pFile->lockingContext) - strlen(DOTLOCK_SUFFIX);
+ memcpy(dbPath, (char *)pFile->lockingContext, len + 1);
+ }else{
+ /* all other styles use the locking context to store the db file path */
+ assert( strlen((char*)pFile->lockingContext)<=MAXPATHLEN );
+ strlcpy(dbPath, (char *)pFile->lockingContext, MAXPATHLEN);
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Takes an already filled in unix file and alters it so all file locking
+** will be performed on the local proxy lock file. The following fields
+** are preserved in the locking context so that they can be restored and
+** the unix structure properly cleaned up at close time:
+** ->lockingContext
+** ->pMethod
+*/
+static int proxyTransformUnixFile(unixFile *pFile, const char *path) {
+ proxyLockingContext *pCtx;
+ char dbPath[MAXPATHLEN+1]; /* Name of the database file */
+ char *lockPath=NULL;
+ int rc = SQLITE_OK;
+
+ if( pFile->eFileLock!=NO_LOCK ){
+ return SQLITE_BUSY;
+ }
+ proxyGetDbPathForUnixFile(pFile, dbPath);
+ if( !path || path[0]=='\0' || !strcmp(path, ":auto:") ){
+ lockPath=NULL;
+ }else{
+ lockPath=(char *)path;
+ }
+
+ OSTRACE(("TRANSPROXY %d for %s pid=%d\n", pFile->h,
+ (lockPath ? lockPath : ":auto:"), getpid()));
+
+ pCtx = sqlite3_malloc( sizeof(*pCtx) );
+ if( pCtx==0 ){
+ return SQLITE_NOMEM;
+ }
+ memset(pCtx, 0, sizeof(*pCtx));
+
+ rc = proxyCreateConchPathname(dbPath, &pCtx->conchFilePath);
+ if( rc==SQLITE_OK ){
+ rc = proxyCreateUnixFile(pCtx->conchFilePath, &pCtx->conchFile, 0);
+ if( rc==SQLITE_CANTOPEN && ((pFile->openFlags&O_RDWR) == 0) ){
+ /* if (a) the open flags are not O_RDWR, (b) the conch isn't there, and
+ ** (c) the file system is read-only, then enable no-locking access.
+ ** Ugh, since O_RDONLY==0x0000 we test for !O_RDWR since unixOpen asserts
+ ** that openFlags will have only one of O_RDONLY or O_RDWR.
+ */
+ struct statfs fsInfo;
+ struct stat conchInfo;
+ int goLockless = 0;
+
+ if( osStat(pCtx->conchFilePath, &conchInfo) == -1 ) {
+ int err = errno;
+ if( (err==ENOENT) && (statfs(dbPath, &fsInfo) != -1) ){
+ goLockless = (fsInfo.f_flags&MNT_RDONLY) == MNT_RDONLY;
+ }
+ }
+ if( goLockless ){
+ pCtx->conchHeld = -1; /* read only FS/ lockless */
+ rc = SQLITE_OK;
+ }
+ }
+ }
+ if( rc==SQLITE_OK && lockPath ){
+ pCtx->lockProxyPath = sqlite3DbStrDup(0, lockPath);
+ }
+
+ if( rc==SQLITE_OK ){
+ pCtx->dbPath = sqlite3DbStrDup(0, dbPath);
+ if( pCtx->dbPath==NULL ){
+ rc = SQLITE_NOMEM;
+ }
+ }
+ if( rc==SQLITE_OK ){
+ /* all memory is allocated, proxys are created and assigned,
+ ** switch the locking context and pMethod then return.
+ */
+ pCtx->oldLockingContext = pFile->lockingContext;
+ pFile->lockingContext = pCtx;
+ pCtx->pOldMethod = pFile->pMethod;
+ pFile->pMethod = &proxyIoMethods;
+ }else{
+ if( pCtx->conchFile ){
+ pCtx->conchFile->pMethod->xClose((sqlite3_file *)pCtx->conchFile);
+ sqlite3_free(pCtx->conchFile);
+ }
+ sqlite3DbFree(0, pCtx->lockProxyPath);
+ sqlite3_free(pCtx->conchFilePath);
+ sqlite3_free(pCtx);
+ }
+ OSTRACE(("TRANSPROXY %d %s\n", pFile->h,
+ (rc==SQLITE_OK ? "ok" : "failed")));
+ return rc;
+}
+
+
+/*
+** This routine handles sqlite3_file_control() calls that are specific
+** to proxy locking.
+*/
+static int proxyFileControl(sqlite3_file *id, int op, void *pArg){
+ switch( op ){
+ case SQLITE_GET_LOCKPROXYFILE: {
+ unixFile *pFile = (unixFile*)id;
+ if( pFile->pMethod == &proxyIoMethods ){
+ proxyLockingContext *pCtx = (proxyLockingContext*)pFile->lockingContext;
+ proxyTakeConch(pFile);
+ if( pCtx->lockProxyPath ){
+ *(const char **)pArg = pCtx->lockProxyPath;
+ }else{
+ *(const char **)pArg = ":auto: (not held)";
+ }
+ } else {
+ *(const char **)pArg = NULL;
+ }
+ return SQLITE_OK;
+ }
+ case SQLITE_SET_LOCKPROXYFILE: {
+ unixFile *pFile = (unixFile*)id;
+ int rc = SQLITE_OK;
+ int isProxyStyle = (pFile->pMethod == &proxyIoMethods);
+ if( pArg==NULL || (const char *)pArg==0 ){
+ if( isProxyStyle ){
+ /* turn off proxy locking - not supported */
+ rc = SQLITE_ERROR /*SQLITE_PROTOCOL? SQLITE_MISUSE?*/;
+ }else{
+ /* turn off proxy locking - already off - NOOP */
+ rc = SQLITE_OK;
+ }
+ }else{
+ const char *proxyPath = (const char *)pArg;
+ if( isProxyStyle ){
+ proxyLockingContext *pCtx =
+ (proxyLockingContext*)pFile->lockingContext;
+ if( !strcmp(pArg, ":auto:")
+ || (pCtx->lockProxyPath &&
+ !strncmp(pCtx->lockProxyPath, proxyPath, MAXPATHLEN))
+ ){
+ rc = SQLITE_OK;
+ }else{
+ rc = switchLockProxyPath(pFile, proxyPath);
+ }
+ }else{
+ /* turn on proxy file locking */
+ rc = proxyTransformUnixFile(pFile, proxyPath);
+ }
+ }
+ return rc;
+ }
+ default: {
+ assert( 0 ); /* The call assures that only valid opcodes are sent */
+ }
+ }
+ /*NOTREACHED*/
+ return SQLITE_ERROR;
+}
+
+/*
+** Within this division (the proxying locking implementation) the procedures
+** above this point are all utilities. The lock-related methods of the
+** proxy-locking sqlite3_io_method object follow.
+*/
+
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, set *pResOut
+** to a non-zero value otherwise *pResOut is set to zero. The return value
+** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+*/
+static int proxyCheckReservedLock(sqlite3_file *id, int *pResOut) {
+ unixFile *pFile = (unixFile*)id;
+ int rc = proxyTakeConch(pFile);
+ if( rc==SQLITE_OK ){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ if( pCtx->conchHeld>0 ){
+ unixFile *proxy = pCtx->lockProxy;
+ return proxy->pMethod->xCheckReservedLock((sqlite3_file*)proxy, pResOut);
+ }else{ /* conchHeld < 0 is lockless */
+ pResOut=0;
+ }
+ }
+ return rc;
+}
+
+/*
+** Lock the file with the lock specified by parameter eFileLock - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. Use the sqlite3OsUnlock()
+** routine to lower a locking level.
+*/
+static int proxyLock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ int rc = proxyTakeConch(pFile);
+ if( rc==SQLITE_OK ){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ if( pCtx->conchHeld>0 ){
+ unixFile *proxy = pCtx->lockProxy;
+ rc = proxy->pMethod->xLock((sqlite3_file*)proxy, eFileLock);
+ pFile->eFileLock = proxy->eFileLock;
+ }else{
+ /* conchHeld < 0 is lockless */
+ }
+ }
+ return rc;
+}
+
+
+/*
+** Lower the locking level on file descriptor pFile to eFileLock. eFileLock
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+*/
+static int proxyUnlock(sqlite3_file *id, int eFileLock) {
+ unixFile *pFile = (unixFile*)id;
+ int rc = proxyTakeConch(pFile);
+ if( rc==SQLITE_OK ){
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ if( pCtx->conchHeld>0 ){
+ unixFile *proxy = pCtx->lockProxy;
+ rc = proxy->pMethod->xUnlock((sqlite3_file*)proxy, eFileLock);
+ pFile->eFileLock = proxy->eFileLock;
+ }else{
+ /* conchHeld < 0 is lockless */
+ }
+ }
+ return rc;
+}
+
+/*
+** Close a file that uses proxy locks.
+*/
+static int proxyClose(sqlite3_file *id) {
+ if( id ){
+ unixFile *pFile = (unixFile*)id;
+ proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
+ unixFile *lockProxy = pCtx->lockProxy;
+ unixFile *conchFile = pCtx->conchFile;
+ int rc = SQLITE_OK;
+
+ if( lockProxy ){
+ rc = lockProxy->pMethod->xUnlock((sqlite3_file*)lockProxy, NO_LOCK);
+ if( rc ) return rc;
+ rc = lockProxy->pMethod->xClose((sqlite3_file*)lockProxy);
+ if( rc ) return rc;
+ sqlite3_free(lockProxy);
+ pCtx->lockProxy = 0;
+ }
+ if( conchFile ){
+ if( pCtx->conchHeld ){
+ rc = proxyReleaseConch(pFile);
+ if( rc ) return rc;
+ }
+ rc = conchFile->pMethod->xClose((sqlite3_file*)conchFile);
+ if( rc ) return rc;
+ sqlite3_free(conchFile);
+ }
+ sqlite3DbFree(0, pCtx->lockProxyPath);
+ sqlite3_free(pCtx->conchFilePath);
+ sqlite3DbFree(0, pCtx->dbPath);
+ /* restore the original locking context and pMethod then close it */
+ pFile->lockingContext = pCtx->oldLockingContext;
+ pFile->pMethod = pCtx->pOldMethod;
+ sqlite3_free(pCtx);
+ return pFile->pMethod->xClose(id);
+ }
+ return SQLITE_OK;
+}
+
+
+
+#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
+/*
+** The proxy locking style is intended for use with AFP filesystems.
+** And since AFP is only supported on MacOSX, the proxy locking is also
+** restricted to MacOSX.
+**
+**
+******************* End of the proxy lock implementation **********************
+******************************************************************************/
+
+/*
+** Initialize the operating system interface.
+**
+** This routine registers all VFS implementations for unix-like operating
+** systems. This routine, and the sqlite3_os_end() routine that follows,
+** should be the only routines in this file that are visible from other
+** files.
+**
+** This routine is called once during SQLite initialization and by a
+** single thread. The memory allocation and mutex subsystems have not
+** necessarily been initialized when this routine is called, and so they
+** should not be used.
+*/
+SQLITE_API int sqlite3_os_init(void){
+ /*
+ ** The following macro defines an initializer for an sqlite3_vfs object.
+ ** The name of the VFS is NAME. The pAppData is a pointer to a pointer
+ ** to the "finder" function. (pAppData is a pointer to a pointer because
+ ** silly C90 rules prohibit a void* from being cast to a function pointer
+ ** and so we have to go through the intermediate pointer to avoid problems
+ ** when compiling with -pedantic-errors on GCC.)
+ **
+ ** The FINDER parameter to this macro is the name of the pointer to the
+ ** finder-function. The finder-function returns a pointer to the
+ ** sqlite_io_methods object that implements the desired locking
+ ** behaviors. See the division above that contains the IOMETHODS
+ ** macro for addition information on finder-functions.
+ **
+ ** Most finders simply return a pointer to a fixed sqlite3_io_methods
+ ** object. But the "autolockIoFinder" available on MacOSX does a little
+ ** more than that; it looks at the filesystem type that hosts the
+ ** database file and tries to choose an locking method appropriate for
+ ** that filesystem time.
+ */
+ #define UNIXVFS(VFSNAME, FINDER) { \
+ 3, /* iVersion */ \
+ sizeof(unixFile), /* szOsFile */ \
+ MAX_PATHNAME, /* mxPathname */ \
+ 0, /* pNext */ \
+ VFSNAME, /* zName */ \
+ (void*)&FINDER, /* pAppData */ \
+ unixOpen, /* xOpen */ \
+ unixDelete, /* xDelete */ \
+ unixAccess, /* xAccess */ \
+ unixFullPathname, /* xFullPathname */ \
+ unixDlOpen, /* xDlOpen */ \
+ unixDlError, /* xDlError */ \
+ unixDlSym, /* xDlSym */ \
+ unixDlClose, /* xDlClose */ \
+ unixRandomness, /* xRandomness */ \
+ unixSleep, /* xSleep */ \
+ unixCurrentTime, /* xCurrentTime */ \
+ unixGetLastError, /* xGetLastError */ \
+ unixCurrentTimeInt64, /* xCurrentTimeInt64 */ \
+ unixSetSystemCall, /* xSetSystemCall */ \
+ unixGetSystemCall, /* xGetSystemCall */ \
+ unixNextSystemCall, /* xNextSystemCall */ \
+ }
+
+ /*
+ ** All default VFSes for unix are contained in the following array.
+ **
+ ** Note that the sqlite3_vfs.pNext field of the VFS object is modified
+ ** by the SQLite core when the VFS is registered. So the following
+ ** array cannot be const.
+ */
+ static sqlite3_vfs aVfs[] = {
+#if SQLITE_ENABLE_LOCKING_STYLE && (OS_VXWORKS || defined(__APPLE__))
+ UNIXVFS("unix", autolockIoFinder ),
+#else
+ UNIXVFS("unix", posixIoFinder ),
+#endif
+ UNIXVFS("unix-none", nolockIoFinder ),
+ UNIXVFS("unix-dotfile", dotlockIoFinder ),
+ UNIXVFS("unix-excl", posixIoFinder ),
+#if OS_VXWORKS
+ UNIXVFS("unix-namedsem", semIoFinder ),
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE
+ UNIXVFS("unix-posix", posixIoFinder ),
+#if !OS_VXWORKS
+ UNIXVFS("unix-flock", flockIoFinder ),
+#endif
+#endif
+#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
+ UNIXVFS("unix-afp", afpIoFinder ),
+ UNIXVFS("unix-nfs", nfsIoFinder ),
+ UNIXVFS("unix-proxy", proxyIoFinder ),
+#endif
+ };
+ unsigned int i; /* Loop counter */
+
+ /* Double-check that the aSyscall[] array has been constructed
+ ** correctly. See ticket [bb3a86e890c8e96ab] */
+ assert( ArraySize(aSyscall)==25 );
+
+ /* Register all VFSes defined in the aVfs[] array */
+ for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
+ sqlite3_vfs_register(&aVfs[i], i==0);
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Shutdown the operating system interface.
+**
+** Some operating systems might need to do some cleanup in this routine,
+** to release dynamically allocated objects. But not on unix.
+** This routine is a no-op for unix.
+*/
+SQLITE_API int sqlite3_os_end(void){
+ return SQLITE_OK;
+}
+
+#endif /* SQLITE_OS_UNIX */
+
+/************** End of os_unix.c *********************************************/
+/************** Begin file os_win.c ******************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains code that is specific to Windows.
+*/
+#if SQLITE_OS_WIN /* This file is used for Windows only */
+
+/*
+** Include code that is common to all os_*.c files
+*/
+/************** Include os_common.h in the middle of os_win.c ****************/
+/************** Begin file os_common.h ***************************************/
+/*
+** 2004 May 22
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains macros and a little bit of code that is common to
+** all of the platform-specific files (os_*.c) and is #included into those
+** files.
+**
+** This file should be #included by the os_*.c files only. It is not a
+** general purpose header file.
+*/
+#ifndef _OS_COMMON_H_
+#define _OS_COMMON_H_
+
+/*
+** At least two bugs have slipped in because we changed the MEMORY_DEBUG
+** macro to SQLITE_DEBUG and some older makefiles have not yet made the
+** switch. The following code should catch this problem at compile-time.
+*/
+#ifdef MEMORY_DEBUG
+# error "The MEMORY_DEBUG macro is obsolete. Use SQLITE_DEBUG instead."
+#endif
+
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+# ifndef SQLITE_DEBUG_OS_TRACE
+# define SQLITE_DEBUG_OS_TRACE 0
+# endif
+ int sqlite3OSTrace = SQLITE_DEBUG_OS_TRACE;
+# define OSTRACE(X) if( sqlite3OSTrace ) sqlite3DebugPrintf X
+#else
+# define OSTRACE(X)
+#endif
+
+/*
+** Macros for performance tracing. Normally turned off. Only works
+** on i486 hardware.
+*/
+#ifdef SQLITE_PERFORMANCE_TRACE
+
+/*
+** hwtime.h contains inline assembler code for implementing
+** high-performance timing routines.
+*/
+/************** Include hwtime.h in the middle of os_common.h ****************/
+/************** Begin file hwtime.h ******************************************/
+/*
+** 2008 May 27
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains inline asm code for retrieving "high-performance"
+** counters for x86 class CPUs.
+*/
+#ifndef _HWTIME_H_
+#define _HWTIME_H_
+
+/*
+** The following routine only works on pentium-class (or newer) processors.
+** It uses the RDTSC opcode to read the cycle count value out of the
+** processor and returns that value. This can be used for high-res
+** profiling.
+*/
+#if (defined(__GNUC__) || defined(_MSC_VER)) && \
+ (defined(i386) || defined(__i386__) || defined(_M_IX86))
+
+ #if defined(__GNUC__)
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned int lo, hi;
+ __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+ return (sqlite_uint64)hi << 32 | lo;
+ }
+
+ #elif defined(_MSC_VER)
+
+ __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
+ __asm {
+ rdtsc
+ ret ; return value at EDX:EAX
+ }
+ }
+
+ #endif
+
+#elif (defined(__GNUC__) && defined(__x86_64__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long val;
+ __asm__ __volatile__ ("rdtsc" : "=A" (val));
+ return val;
+ }
+
+#elif (defined(__GNUC__) && defined(__ppc__))
+
+ __inline__ sqlite_uint64 sqlite3Hwtime(void){
+ unsigned long long retval;
+ unsigned long junk;
+ __asm__ __volatile__ ("\n\
+ 1: mftbu %1\n\
+ mftb %L0\n\
+ mftbu %0\n\
+ cmpw %0,%1\n\
+ bne 1b"
+ : "=r" (retval), "=r" (junk));
+ return retval;
+ }
+
+#else
+
+ #error Need implementation of sqlite3Hwtime() for your platform.
+
+ /*
+ ** To compile without implementing sqlite3Hwtime() for your platform,
+ ** you can remove the above #error and use the following
+ ** stub function. You will lose timing support for many
+ ** of the debugging and testing utilities, but it should at
+ ** least compile and run.
+ */
+SQLITE_PRIVATE sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
+
+#endif
+
+#endif /* !defined(_HWTIME_H_) */
+
+/************** End of hwtime.h **********************************************/
+/************** Continuing where we left off in os_common.h ******************/
+
+static sqlite_uint64 g_start;
+static sqlite_uint64 g_elapsed;
+#define TIMER_START g_start=sqlite3Hwtime()
+#define TIMER_END g_elapsed=sqlite3Hwtime()-g_start
+#define TIMER_ELAPSED g_elapsed
+#else
+#define TIMER_START
+#define TIMER_END
+#define TIMER_ELAPSED ((sqlite_uint64)0)
+#endif
+
+/*
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error. This
+** is used for testing the I/O recovery logic.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_io_error_hit = 0; /* Total number of I/O Errors */
+SQLITE_API int sqlite3_io_error_hardhit = 0; /* Number of non-benign errors */
+SQLITE_API int sqlite3_io_error_pending = 0; /* Count down to first I/O error */
+SQLITE_API int sqlite3_io_error_persist = 0; /* True if I/O errors persist */
+SQLITE_API int sqlite3_io_error_benign = 0; /* True if errors are benign */
+SQLITE_API int sqlite3_diskfull_pending = 0;
+SQLITE_API int sqlite3_diskfull = 0;
+#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
+#define SimulateIOError(CODE) \
+ if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
+ || sqlite3_io_error_pending-- == 1 ) \
+ { local_ioerr(); CODE; }
+static void local_ioerr(){
+ IOTRACE(("IOERR\n"));
+ sqlite3_io_error_hit++;
+ if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
+}
+#define SimulateDiskfullError(CODE) \
+ if( sqlite3_diskfull_pending ){ \
+ if( sqlite3_diskfull_pending == 1 ){ \
+ local_ioerr(); \
+ sqlite3_diskfull = 1; \
+ sqlite3_io_error_hit = 1; \
+ CODE; \
+ }else{ \
+ sqlite3_diskfull_pending--; \
+ } \
+ }
+#else
+#define SimulateIOErrorBenign(X)
+#define SimulateIOError(A)
+#define SimulateDiskfullError(A)
+#endif
+
+/*
+** When testing, keep a count of the number of open files.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_open_file_count = 0;
+#define OpenCounter(X) sqlite3_open_file_count+=(X)
+#else
+#define OpenCounter(X)
+#endif
+
+#endif /* !defined(_OS_COMMON_H_) */
+
+/************** End of os_common.h *******************************************/
+/************** Continuing where we left off in os_win.c *********************/
+
+/*
+** Include the header file for the Windows VFS.
+*/
+
+/*
+** Compiling and using WAL mode requires several APIs that are only
+** available in Windows platforms based on the NT kernel.
+*/
+#if !SQLITE_OS_WINNT && !defined(SQLITE_OMIT_WAL)
+# error "WAL mode requires support from the Windows NT kernel, compile\
+ with SQLITE_OMIT_WAL."
+#endif
+
+/*
+** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
+** based on the sub-platform)?
+*/
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(SQLITE_WIN32_NO_ANSI)
+# define SQLITE_WIN32_HAS_ANSI
+#endif
+
+/*
+** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
+** based on the sub-platform)?
+*/
+#if (SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT) && \
+ !defined(SQLITE_WIN32_NO_WIDE)
+# define SQLITE_WIN32_HAS_WIDE
+#endif
+
+/*
+** Make sure at least one set of Win32 APIs is available.
+*/
+#if !defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_WIN32_HAS_WIDE)
+# error "At least one of SQLITE_WIN32_HAS_ANSI and SQLITE_WIN32_HAS_WIDE\
+ must be defined."
+#endif
+
+/*
+** Define the required Windows SDK version constants if they are not
+** already available.
+*/
+#ifndef NTDDI_WIN8
+# define NTDDI_WIN8 0x06020000
+#endif
+
+#ifndef NTDDI_WINBLUE
+# define NTDDI_WINBLUE 0x06030000
+#endif
+
+/*
+** Check if the GetVersionEx[AW] functions should be considered deprecated
+** and avoid using them in that case. It should be noted here that if the
+** value of the SQLITE_WIN32_GETVERSIONEX pre-processor macro is zero
+** (whether via this block or via being manually specified), that implies
+** the underlying operating system will always be based on the Windows NT
+** Kernel.
+*/
+#ifndef SQLITE_WIN32_GETVERSIONEX
+# if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WINBLUE
+# define SQLITE_WIN32_GETVERSIONEX 0
+# else
+# define SQLITE_WIN32_GETVERSIONEX 1
+# endif
+#endif
+
+/*
+** This constant should already be defined (in the "WinDef.h" SDK file).
+*/
+#ifndef MAX_PATH
+# define MAX_PATH (260)
+#endif
+
+/*
+** Maximum pathname length (in chars) for Win32. This should normally be
+** MAX_PATH.
+*/
+#ifndef SQLITE_WIN32_MAX_PATH_CHARS
+# define SQLITE_WIN32_MAX_PATH_CHARS (MAX_PATH)
+#endif
+
+/*
+** This constant should already be defined (in the "WinNT.h" SDK file).
+*/
+#ifndef UNICODE_STRING_MAX_CHARS
+# define UNICODE_STRING_MAX_CHARS (32767)
+#endif
+
+/*
+** Maximum pathname length (in chars) for WinNT. This should normally be
+** UNICODE_STRING_MAX_CHARS.
+*/
+#ifndef SQLITE_WINNT_MAX_PATH_CHARS
+# define SQLITE_WINNT_MAX_PATH_CHARS (UNICODE_STRING_MAX_CHARS)
+#endif
+
+/*
+** Maximum pathname length (in bytes) for Win32. The MAX_PATH macro is in
+** characters, so we allocate 4 bytes per character assuming worst-case of
+** 4-bytes-per-character for UTF8.
+*/
+#ifndef SQLITE_WIN32_MAX_PATH_BYTES
+# define SQLITE_WIN32_MAX_PATH_BYTES (SQLITE_WIN32_MAX_PATH_CHARS*4)
+#endif
+
+/*
+** Maximum pathname length (in bytes) for WinNT. This should normally be
+** UNICODE_STRING_MAX_CHARS * sizeof(WCHAR).
+*/
+#ifndef SQLITE_WINNT_MAX_PATH_BYTES
+# define SQLITE_WINNT_MAX_PATH_BYTES \
+ (sizeof(WCHAR) * SQLITE_WINNT_MAX_PATH_CHARS)
+#endif
+
+/*
+** Maximum error message length (in chars) for WinRT.
+*/
+#ifndef SQLITE_WIN32_MAX_ERRMSG_CHARS
+# define SQLITE_WIN32_MAX_ERRMSG_CHARS (1024)
+#endif
+
+/*
+** Returns non-zero if the character should be treated as a directory
+** separator.
+*/
+#ifndef winIsDirSep
+# define winIsDirSep(a) (((a) == '/') || ((a) == '\\'))
+#endif
+
+/*
+** This macro is used when a local variable is set to a value that is
+** [sometimes] not used by the code (e.g. via conditional compilation).
+*/
+#ifndef UNUSED_VARIABLE_VALUE
+# define UNUSED_VARIABLE_VALUE(x) (void)(x)
+#endif
+
+/*
+** Returns the character that should be used as the directory separator.
+*/
+#ifndef winGetDirSep
+# define winGetDirSep() '\\'
+#endif
+
+/*
+** Do we need to manually define the Win32 file mapping APIs for use with WAL
+** mode (e.g. these APIs are available in the Windows CE SDK; however, they
+** are not present in the header file)?
+*/
+#if SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL)
+/*
+** Two of the file mapping APIs are different under WinRT. Figure out which
+** set we need.
+*/
+#if SQLITE_OS_WINRT
+WINBASEAPI HANDLE WINAPI CreateFileMappingFromApp(HANDLE, \
+ LPSECURITY_ATTRIBUTES, ULONG, ULONG64, LPCWSTR);
+
+WINBASEAPI LPVOID WINAPI MapViewOfFileFromApp(HANDLE, ULONG, ULONG64, SIZE_T);
+#else
+#if defined(SQLITE_WIN32_HAS_ANSI)
+WINBASEAPI HANDLE WINAPI CreateFileMappingA(HANDLE, LPSECURITY_ATTRIBUTES, \
+ DWORD, DWORD, DWORD, LPCSTR);
+#endif /* defined(SQLITE_WIN32_HAS_ANSI) */
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+WINBASEAPI HANDLE WINAPI CreateFileMappingW(HANDLE, LPSECURITY_ATTRIBUTES, \
+ DWORD, DWORD, DWORD, LPCWSTR);
+#endif /* defined(SQLITE_WIN32_HAS_WIDE) */
+
+WINBASEAPI LPVOID WINAPI MapViewOfFile(HANDLE, DWORD, DWORD, DWORD, SIZE_T);
+#endif /* SQLITE_OS_WINRT */
+
+/*
+** This file mapping API is common to both Win32 and WinRT.
+*/
+WINBASEAPI BOOL WINAPI UnmapViewOfFile(LPCVOID);
+#endif /* SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL) */
+
+/*
+** Some Microsoft compilers lack this definition.
+*/
+#ifndef INVALID_FILE_ATTRIBUTES
+# define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
+#endif
+
+#ifndef FILE_FLAG_MASK
+# define FILE_FLAG_MASK (0xFF3C0000)
+#endif
+
+#ifndef FILE_ATTRIBUTE_MASK
+# define FILE_ATTRIBUTE_MASK (0x0003FFF7)
+#endif
+
+#ifndef SQLITE_OMIT_WAL
+/* Forward references to structures used for WAL */
+typedef struct winShm winShm; /* A connection to shared-memory */
+typedef struct winShmNode winShmNode; /* A region of shared-memory */
+#endif
+
+/*
+** WinCE lacks native support for file locking so we have to fake it
+** with some code of our own.
+*/
+#if SQLITE_OS_WINCE
+typedef struct winceLock {
+ int nReaders; /* Number of reader locks obtained */
+ BOOL bPending; /* Indicates a pending lock has been obtained */
+ BOOL bReserved; /* Indicates a reserved lock has been obtained */
+ BOOL bExclusive; /* Indicates an exclusive lock has been obtained */
+} winceLock;
+#endif
+
+/*
+** The winFile structure is a subclass of sqlite3_file* specific to the win32
+** portability layer.
+*/
+typedef struct winFile winFile;
+struct winFile {
+ const sqlite3_io_methods *pMethod; /*** Must be first ***/
+ sqlite3_vfs *pVfs; /* The VFS used to open this file */
+ HANDLE h; /* Handle for accessing the file */
+ u8 locktype; /* Type of lock currently held on this file */
+ short sharedLockByte; /* Randomly chosen byte used as a shared lock */
+ u8 ctrlFlags; /* Flags. See WINFILE_* below */
+ DWORD lastErrno; /* The Windows errno from the last I/O error */
+#ifndef SQLITE_OMIT_WAL
+ winShm *pShm; /* Instance of shared memory on this file */
+#endif
+ const char *zPath; /* Full pathname of this file */
+ int szChunk; /* Chunk size configured by FCNTL_CHUNK_SIZE */
+#if SQLITE_OS_WINCE
+ LPWSTR zDeleteOnClose; /* Name of file to delete when closing */
+ HANDLE hMutex; /* Mutex used to control access to shared lock */
+ HANDLE hShared; /* Shared memory segment used for locking */
+ winceLock local; /* Locks obtained by this instance of winFile */
+ winceLock *shared; /* Global shared lock memory for the file */
+#endif
+#if SQLITE_MAX_MMAP_SIZE>0
+ int nFetchOut; /* Number of outstanding xFetch references */
+ HANDLE hMap; /* Handle for accessing memory mapping */
+ void *pMapRegion; /* Area memory mapped */
+ sqlite3_int64 mmapSize; /* Usable size of mapped region */
+ sqlite3_int64 mmapSizeActual; /* Actual size of mapped region */
+ sqlite3_int64 mmapSizeMax; /* Configured FCNTL_MMAP_SIZE value */
+#endif
+};
+
+/*
+** Allowed values for winFile.ctrlFlags
+*/
+#define WINFILE_RDONLY 0x02 /* Connection is read only */
+#define WINFILE_PERSIST_WAL 0x04 /* Persistent WAL mode */
+#define WINFILE_PSOW 0x10 /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
+
+/*
+ * The size of the buffer used by sqlite3_win32_write_debug().
+ */
+#ifndef SQLITE_WIN32_DBG_BUF_SIZE
+# define SQLITE_WIN32_DBG_BUF_SIZE ((int)(4096-sizeof(DWORD)))
+#endif
+
+/*
+ * The value used with sqlite3_win32_set_directory() to specify that
+ * the data directory should be changed.
+ */
+#ifndef SQLITE_WIN32_DATA_DIRECTORY_TYPE
+# define SQLITE_WIN32_DATA_DIRECTORY_TYPE (1)
+#endif
+
+/*
+ * The value used with sqlite3_win32_set_directory() to specify that
+ * the temporary directory should be changed.
+ */
+#ifndef SQLITE_WIN32_TEMP_DIRECTORY_TYPE
+# define SQLITE_WIN32_TEMP_DIRECTORY_TYPE (2)
+#endif
+
+/*
+ * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
+ * various Win32 API heap functions instead of our own.
+ */
+#ifdef SQLITE_WIN32_MALLOC
+
+/*
+ * If this is non-zero, an isolated heap will be created by the native Win32
+ * allocator subsystem; otherwise, the default process heap will be used. This
+ * setting has no effect when compiling for WinRT. By default, this is enabled
+ * and an isolated heap will be created to store all allocated data.
+ *
+ ******************************************************************************
+ * WARNING: It is important to note that when this setting is non-zero and the
+ * winMemShutdown function is called (e.g. by the sqlite3_shutdown
+ * function), all data that was allocated using the isolated heap will
+ * be freed immediately and any attempt to access any of that freed
+ * data will almost certainly result in an immediate access violation.
+ ******************************************************************************
+ */
+#ifndef SQLITE_WIN32_HEAP_CREATE
+# define SQLITE_WIN32_HEAP_CREATE (TRUE)
+#endif
+
+/*
+ * The initial size of the Win32-specific heap. This value may be zero.
+ */
+#ifndef SQLITE_WIN32_HEAP_INIT_SIZE
+# define SQLITE_WIN32_HEAP_INIT_SIZE ((SQLITE_DEFAULT_CACHE_SIZE) * \
+ (SQLITE_DEFAULT_PAGE_SIZE) + 4194304)
+#endif
+
+/*
+ * The maximum size of the Win32-specific heap. This value may be zero.
+ */
+#ifndef SQLITE_WIN32_HEAP_MAX_SIZE
+# define SQLITE_WIN32_HEAP_MAX_SIZE (0)
+#endif
+
+/*
+ * The extra flags to use in calls to the Win32 heap APIs. This value may be
+ * zero for the default behavior.
+ */
+#ifndef SQLITE_WIN32_HEAP_FLAGS
+# define SQLITE_WIN32_HEAP_FLAGS (0)
+#endif
+
+
+/*
+** The winMemData structure stores information required by the Win32-specific
+** sqlite3_mem_methods implementation.
+*/
+typedef struct winMemData winMemData;
+struct winMemData {
+#ifndef NDEBUG
+ u32 magic1; /* Magic number to detect structure corruption. */
+#endif
+ HANDLE hHeap; /* The handle to our heap. */
+ BOOL bOwned; /* Do we own the heap (i.e. destroy it on shutdown)? */
+#ifndef NDEBUG
+ u32 magic2; /* Magic number to detect structure corruption. */
+#endif
+};
+
+#ifndef NDEBUG
+#define WINMEM_MAGIC1 0x42b2830b
+#define WINMEM_MAGIC2 0xbd4d7cf4
+#endif
+
+static struct winMemData win_mem_data = {
+#ifndef NDEBUG
+ WINMEM_MAGIC1,
+#endif
+ NULL, FALSE
+#ifndef NDEBUG
+ ,WINMEM_MAGIC2
+#endif
+};
+
+#ifndef NDEBUG
+#define winMemAssertMagic1() assert( win_mem_data.magic1==WINMEM_MAGIC1 )
+#define winMemAssertMagic2() assert( win_mem_data.magic2==WINMEM_MAGIC2 )
+#define winMemAssertMagic() winMemAssertMagic1(); winMemAssertMagic2();
+#else
+#define winMemAssertMagic()
+#endif
+
+#define winMemGetDataPtr() &win_mem_data
+#define winMemGetHeap() win_mem_data.hHeap
+#define winMemGetOwned() win_mem_data.bOwned
+
+static void *winMemMalloc(int nBytes);
+static void winMemFree(void *pPrior);
+static void *winMemRealloc(void *pPrior, int nBytes);
+static int winMemSize(void *p);
+static int winMemRoundup(int n);
+static int winMemInit(void *pAppData);
+static void winMemShutdown(void *pAppData);
+
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetWin32(void);
+#endif /* SQLITE_WIN32_MALLOC */
+
+/*
+** The following variable is (normally) set once and never changes
+** thereafter. It records whether the operating system is Win9x
+** or WinNT.
+**
+** 0: Operating system unknown.
+** 1: Operating system is Win9x.
+** 2: Operating system is WinNT.
+**
+** In order to facilitate testing on a WinNT system, the test fixture
+** can manually set this value to 1 to emulate Win98 behavior.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_os_type = 0;
+#elif !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && \
+ defined(SQLITE_WIN32_HAS_ANSI) && defined(SQLITE_WIN32_HAS_WIDE)
+static int sqlite3_os_type = 0;
+#endif
+
+#ifndef SYSCALL
+# define SYSCALL sqlite3_syscall_ptr
+#endif
+
+/*
+** This function is not available on Windows CE or WinRT.
+ */
+
+#if SQLITE_OS_WINCE || SQLITE_OS_WINRT
+# define osAreFileApisANSI() 1
+#endif
+
+/*
+** Many system calls are accessed through pointer-to-functions so that
+** they may be overridden at runtime to facilitate fault injection during
+** testing and sandboxing. The following array holds the names and pointers
+** to all overrideable system calls.
+*/
+static struct win_syscall {
+ const char *zName; /* Name of the system call */
+ sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
+ sqlite3_syscall_ptr pDefault; /* Default value */
+} aSyscall[] = {
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "AreFileApisANSI", (SYSCALL)AreFileApisANSI, 0 },
+#else
+ { "AreFileApisANSI", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osAreFileApisANSI
+#define osAreFileApisANSI ((BOOL(WINAPI*)(VOID))aSyscall[0].pCurrent)
+#endif
+
+#if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CharLowerW", (SYSCALL)CharLowerW, 0 },
+#else
+ { "CharLowerW", (SYSCALL)0, 0 },
+#endif
+
+#define osCharLowerW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[1].pCurrent)
+
+#if SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CharUpperW", (SYSCALL)CharUpperW, 0 },
+#else
+ { "CharUpperW", (SYSCALL)0, 0 },
+#endif
+
+#define osCharUpperW ((LPWSTR(WINAPI*)(LPWSTR))aSyscall[2].pCurrent)
+
+ { "CloseHandle", (SYSCALL)CloseHandle, 0 },
+
+#define osCloseHandle ((BOOL(WINAPI*)(HANDLE))aSyscall[3].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "CreateFileA", (SYSCALL)CreateFileA, 0 },
+#else
+ { "CreateFileA", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileA ((HANDLE(WINAPI*)(LPCSTR,DWORD,DWORD, \
+ LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[4].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CreateFileW", (SYSCALL)CreateFileW, 0 },
+#else
+ { "CreateFileW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
+ LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)
+
+#if (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_ANSI) && \
+ !defined(SQLITE_OMIT_WAL))
+ { "CreateFileMappingA", (SYSCALL)CreateFileMappingA, 0 },
+#else
+ { "CreateFileMappingA", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileMappingA ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
+ DWORD,DWORD,DWORD,LPCSTR))aSyscall[6].pCurrent)
+
+#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+ !defined(SQLITE_OMIT_WAL))
+ { "CreateFileMappingW", (SYSCALL)CreateFileMappingW, 0 },
+#else
+ { "CreateFileMappingW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
+ DWORD,DWORD,DWORD,LPCWSTR))aSyscall[7].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "CreateMutexW", (SYSCALL)CreateMutexW, 0 },
+#else
+ { "CreateMutexW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateMutexW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,BOOL, \
+ LPCWSTR))aSyscall[8].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "DeleteFileA", (SYSCALL)DeleteFileA, 0 },
+#else
+ { "DeleteFileA", (SYSCALL)0, 0 },
+#endif
+
+#define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[9].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "DeleteFileW", (SYSCALL)DeleteFileW, 0 },
+#else
+ { "DeleteFileW", (SYSCALL)0, 0 },
+#endif
+
+#define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[10].pCurrent)
+
+#if SQLITE_OS_WINCE
+ { "FileTimeToLocalFileTime", (SYSCALL)FileTimeToLocalFileTime, 0 },
+#else
+ { "FileTimeToLocalFileTime", (SYSCALL)0, 0 },
+#endif
+
+#define osFileTimeToLocalFileTime ((BOOL(WINAPI*)(CONST FILETIME*, \
+ LPFILETIME))aSyscall[11].pCurrent)
+
+#if SQLITE_OS_WINCE
+ { "FileTimeToSystemTime", (SYSCALL)FileTimeToSystemTime, 0 },
+#else
+ { "FileTimeToSystemTime", (SYSCALL)0, 0 },
+#endif
+
+#define osFileTimeToSystemTime ((BOOL(WINAPI*)(CONST FILETIME*, \
+ LPSYSTEMTIME))aSyscall[12].pCurrent)
+
+ { "FlushFileBuffers", (SYSCALL)FlushFileBuffers, 0 },
+
+#define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[13].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "FormatMessageA", (SYSCALL)FormatMessageA, 0 },
+#else
+ { "FormatMessageA", (SYSCALL)0, 0 },
+#endif
+
+#define osFormatMessageA ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPSTR, \
+ DWORD,va_list*))aSyscall[14].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "FormatMessageW", (SYSCALL)FormatMessageW, 0 },
+#else
+ { "FormatMessageW", (SYSCALL)0, 0 },
+#endif
+
+#define osFormatMessageW ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPWSTR, \
+ DWORD,va_list*))aSyscall[15].pCurrent)
+
+#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "FreeLibrary", (SYSCALL)FreeLibrary, 0 },
+#else
+ { "FreeLibrary", (SYSCALL)0, 0 },
+#endif
+
+#define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[16].pCurrent)
+
+ { "GetCurrentProcessId", (SYSCALL)GetCurrentProcessId, 0 },
+
+#define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[17].pCurrent)
+
+#if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetDiskFreeSpaceA", (SYSCALL)GetDiskFreeSpaceA, 0 },
+#else
+ { "GetDiskFreeSpaceA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetDiskFreeSpaceA ((BOOL(WINAPI*)(LPCSTR,LPDWORD,LPDWORD,LPDWORD, \
+ LPDWORD))aSyscall[18].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetDiskFreeSpaceW", (SYSCALL)GetDiskFreeSpaceW, 0 },
+#else
+ { "GetDiskFreeSpaceW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetDiskFreeSpaceW ((BOOL(WINAPI*)(LPCWSTR,LPDWORD,LPDWORD,LPDWORD, \
+ LPDWORD))aSyscall[19].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetFileAttributesA", (SYSCALL)GetFileAttributesA, 0 },
+#else
+ { "GetFileAttributesA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[20].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetFileAttributesW", (SYSCALL)GetFileAttributesW, 0 },
+#else
+ { "GetFileAttributesW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[21].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetFileAttributesExW", (SYSCALL)GetFileAttributesExW, 0 },
+#else
+ { "GetFileAttributesExW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileAttributesExW ((BOOL(WINAPI*)(LPCWSTR,GET_FILEEX_INFO_LEVELS, \
+ LPVOID))aSyscall[22].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "GetFileSize", (SYSCALL)GetFileSize, 0 },
+#else
+ { "GetFileSize", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[23].pCurrent)
+
+#if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetFullPathNameA", (SYSCALL)GetFullPathNameA, 0 },
+#else
+ { "GetFullPathNameA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFullPathNameA ((DWORD(WINAPI*)(LPCSTR,DWORD,LPSTR, \
+ LPSTR*))aSyscall[24].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetFullPathNameW", (SYSCALL)GetFullPathNameW, 0 },
+#else
+ { "GetFullPathNameW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFullPathNameW ((DWORD(WINAPI*)(LPCWSTR,DWORD,LPWSTR, \
+ LPWSTR*))aSyscall[25].pCurrent)
+
+ { "GetLastError", (SYSCALL)GetLastError, 0 },
+
+#define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[26].pCurrent)
+
+#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
+#if SQLITE_OS_WINCE
+ /* The GetProcAddressA() routine is only available on Windows CE. */
+ { "GetProcAddressA", (SYSCALL)GetProcAddressA, 0 },
+#else
+ /* All other Windows platforms expect GetProcAddress() to take
+ ** an ANSI string regardless of the _UNICODE setting */
+ { "GetProcAddressA", (SYSCALL)GetProcAddress, 0 },
+#endif
+#else
+ { "GetProcAddressA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetProcAddressA ((FARPROC(WINAPI*)(HMODULE, \
+ LPCSTR))aSyscall[27].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "GetSystemInfo", (SYSCALL)GetSystemInfo, 0 },
+#else
+ { "GetSystemInfo", (SYSCALL)0, 0 },
+#endif
+
+#define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[28].pCurrent)
+
+ { "GetSystemTime", (SYSCALL)GetSystemTime, 0 },
+
+#define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[29].pCurrent)
+
+#if !SQLITE_OS_WINCE
+ { "GetSystemTimeAsFileTime", (SYSCALL)GetSystemTimeAsFileTime, 0 },
+#else
+ { "GetSystemTimeAsFileTime", (SYSCALL)0, 0 },
+#endif
+
+#define osGetSystemTimeAsFileTime ((VOID(WINAPI*)( \
+ LPFILETIME))aSyscall[30].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "GetTempPathA", (SYSCALL)GetTempPathA, 0 },
+#else
+ { "GetTempPathA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[31].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+ { "GetTempPathW", (SYSCALL)GetTempPathW, 0 },
+#else
+ { "GetTempPathW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[32].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "GetTickCount", (SYSCALL)GetTickCount, 0 },
+#else
+ { "GetTickCount", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[33].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI) && defined(SQLITE_WIN32_GETVERSIONEX) && \
+ SQLITE_WIN32_GETVERSIONEX
+ { "GetVersionExA", (SYSCALL)GetVersionExA, 0 },
+#else
+ { "GetVersionExA", (SYSCALL)0, 0 },
+#endif
+
+#define osGetVersionExA ((BOOL(WINAPI*)( \
+ LPOSVERSIONINFOA))aSyscall[34].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+ defined(SQLITE_WIN32_GETVERSIONEX) && SQLITE_WIN32_GETVERSIONEX
+ { "GetVersionExW", (SYSCALL)GetVersionExW, 0 },
+#else
+ { "GetVersionExW", (SYSCALL)0, 0 },
+#endif
+
+#define osGetVersionExW ((BOOL(WINAPI*)( \
+ LPOSVERSIONINFOW))aSyscall[35].pCurrent)
+
+ { "HeapAlloc", (SYSCALL)HeapAlloc, 0 },
+
+#define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
+ SIZE_T))aSyscall[36].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "HeapCreate", (SYSCALL)HeapCreate, 0 },
+#else
+ { "HeapCreate", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
+ SIZE_T))aSyscall[37].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "HeapDestroy", (SYSCALL)HeapDestroy, 0 },
+#else
+ { "HeapDestroy", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[38].pCurrent)
+
+ { "HeapFree", (SYSCALL)HeapFree, 0 },
+
+#define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[39].pCurrent)
+
+ { "HeapReAlloc", (SYSCALL)HeapReAlloc, 0 },
+
+#define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
+ SIZE_T))aSyscall[40].pCurrent)
+
+ { "HeapSize", (SYSCALL)HeapSize, 0 },
+
+#define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
+ LPCVOID))aSyscall[41].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "HeapValidate", (SYSCALL)HeapValidate, 0 },
+#else
+ { "HeapValidate", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
+ LPCVOID))aSyscall[42].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "HeapCompact", (SYSCALL)HeapCompact, 0 },
+#else
+ { "HeapCompact", (SYSCALL)0, 0 },
+#endif
+
+#define osHeapCompact ((UINT(WINAPI*)(HANDLE,DWORD))aSyscall[43].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "LoadLibraryA", (SYSCALL)LoadLibraryA, 0 },
+#else
+ { "LoadLibraryA", (SYSCALL)0, 0 },
+#endif
+
+#define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[44].pCurrent)
+
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+ !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "LoadLibraryW", (SYSCALL)LoadLibraryW, 0 },
+#else
+ { "LoadLibraryW", (SYSCALL)0, 0 },
+#endif
+
+#define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[45].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "LocalFree", (SYSCALL)LocalFree, 0 },
+#else
+ { "LocalFree", (SYSCALL)0, 0 },
+#endif
+
+#define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[46].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "LockFile", (SYSCALL)LockFile, 0 },
+#else
+ { "LockFile", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osLockFile
+#define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ DWORD))aSyscall[47].pCurrent)
+#endif
+
+#if !SQLITE_OS_WINCE
+ { "LockFileEx", (SYSCALL)LockFileEx, 0 },
+#else
+ { "LockFileEx", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osLockFileEx
+#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
+ LPOVERLAPPED))aSyscall[48].pCurrent)
+#endif
+
+#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL))
+ { "MapViewOfFile", (SYSCALL)MapViewOfFile, 0 },
+#else
+ { "MapViewOfFile", (SYSCALL)0, 0 },
+#endif
+
+#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ SIZE_T))aSyscall[49].pCurrent)
+
+ { "MultiByteToWideChar", (SYSCALL)MultiByteToWideChar, 0 },
+
+#define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
+ int))aSyscall[50].pCurrent)
+
+ { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },
+
+#define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
+ LARGE_INTEGER*))aSyscall[51].pCurrent)
+
+ { "ReadFile", (SYSCALL)ReadFile, 0 },
+
+#define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
+ LPOVERLAPPED))aSyscall[52].pCurrent)
+
+ { "SetEndOfFile", (SYSCALL)SetEndOfFile, 0 },
+
+#define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[53].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "SetFilePointer", (SYSCALL)SetFilePointer, 0 },
+#else
+ { "SetFilePointer", (SYSCALL)0, 0 },
+#endif
+
+#define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
+ DWORD))aSyscall[54].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "Sleep", (SYSCALL)Sleep, 0 },
+#else
+ { "Sleep", (SYSCALL)0, 0 },
+#endif
+
+#define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[55].pCurrent)
+
+ { "SystemTimeToFileTime", (SYSCALL)SystemTimeToFileTime, 0 },
+
+#define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
+ LPFILETIME))aSyscall[56].pCurrent)
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+ { "UnlockFile", (SYSCALL)UnlockFile, 0 },
+#else
+ { "UnlockFile", (SYSCALL)0, 0 },
+#endif
+
+#ifndef osUnlockFile
+#define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ DWORD))aSyscall[57].pCurrent)
+#endif
+
+#if !SQLITE_OS_WINCE
+ { "UnlockFileEx", (SYSCALL)UnlockFileEx, 0 },
+#else
+ { "UnlockFileEx", (SYSCALL)0, 0 },
+#endif
+
+#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
+ LPOVERLAPPED))aSyscall[58].pCurrent)
+
+#if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL)
+ { "UnmapViewOfFile", (SYSCALL)UnmapViewOfFile, 0 },
+#else
+ { "UnmapViewOfFile", (SYSCALL)0, 0 },
+#endif
+
+#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[59].pCurrent)
+
+ { "WideCharToMultiByte", (SYSCALL)WideCharToMultiByte, 0 },
+
+#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
+ LPCSTR,LPBOOL))aSyscall[60].pCurrent)
+
+ { "WriteFile", (SYSCALL)WriteFile, 0 },
+
+#define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
+ LPOVERLAPPED))aSyscall[61].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "CreateEventExW", (SYSCALL)CreateEventExW, 0 },
+#else
+ { "CreateEventExW", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
+ DWORD,DWORD))aSyscall[62].pCurrent)
+
+#if !SQLITE_OS_WINRT
+ { "WaitForSingleObject", (SYSCALL)WaitForSingleObject, 0 },
+#else
+ { "WaitForSingleObject", (SYSCALL)0, 0 },
+#endif
+
+#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
+ DWORD))aSyscall[63].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "WaitForSingleObjectEx", (SYSCALL)WaitForSingleObjectEx, 0 },
+#else
+ { "WaitForSingleObjectEx", (SYSCALL)0, 0 },
+#endif
+
+#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
+ BOOL))aSyscall[64].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "SetFilePointerEx", (SYSCALL)SetFilePointerEx, 0 },
+#else
+ { "SetFilePointerEx", (SYSCALL)0, 0 },
+#endif
+
+#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
+ PLARGE_INTEGER,DWORD))aSyscall[65].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
+#else
+ { "GetFileInformationByHandleEx", (SYSCALL)0, 0 },
+#endif
+
+#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
+ FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[66].pCurrent)
+
+#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
+ { "MapViewOfFileFromApp", (SYSCALL)MapViewOfFileFromApp, 0 },
+#else
+ { "MapViewOfFileFromApp", (SYSCALL)0, 0 },
+#endif
+
+#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
+ SIZE_T))aSyscall[67].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "CreateFile2", (SYSCALL)CreateFile2, 0 },
+#else
+ { "CreateFile2", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
+ LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[68].pCurrent)
+
+#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
+ { "LoadPackagedLibrary", (SYSCALL)LoadPackagedLibrary, 0 },
+#else
+ { "LoadPackagedLibrary", (SYSCALL)0, 0 },
+#endif
+
+#define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
+ DWORD))aSyscall[69].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "GetTickCount64", (SYSCALL)GetTickCount64, 0 },
+#else
+ { "GetTickCount64", (SYSCALL)0, 0 },
+#endif
+
+#define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[70].pCurrent)
+
+#if SQLITE_OS_WINRT
+ { "GetNativeSystemInfo", (SYSCALL)GetNativeSystemInfo, 0 },
+#else
+ { "GetNativeSystemInfo", (SYSCALL)0, 0 },
+#endif
+
+#define osGetNativeSystemInfo ((VOID(WINAPI*)( \
+ LPSYSTEM_INFO))aSyscall[71].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_ANSI)
+ { "OutputDebugStringA", (SYSCALL)OutputDebugStringA, 0 },
+#else
+ { "OutputDebugStringA", (SYSCALL)0, 0 },
+#endif
+
+#define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[72].pCurrent)
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ { "OutputDebugStringW", (SYSCALL)OutputDebugStringW, 0 },
+#else
+ { "OutputDebugStringW", (SYSCALL)0, 0 },
+#endif
+
+#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[73].pCurrent)
+
+ { "GetProcessHeap", (SYSCALL)GetProcessHeap, 0 },
+
+#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[74].pCurrent)
+
+#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
+ { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
+#else
+ { "CreateFileMappingFromApp", (SYSCALL)0, 0 },
+#endif
+
+#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
+ LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[75].pCurrent)
+
+}; /* End of the overrideable system calls */
+
+/*
+** This is the xSetSystemCall() method of sqlite3_vfs for all of the
+** "win32" VFSes. Return SQLITE_OK opon successfully updating the
+** system call pointer, or SQLITE_NOTFOUND if there is no configurable
+** system call named zName.
+*/
+static int winSetSystemCall(
+ sqlite3_vfs *pNotUsed, /* The VFS pointer. Not used */
+ const char *zName, /* Name of system call to override */
+ sqlite3_syscall_ptr pNewFunc /* Pointer to new system call value */
+){
+ unsigned int i;
+ int rc = SQLITE_NOTFOUND;
+
+ UNUSED_PARAMETER(pNotUsed);
+ if( zName==0 ){
+ /* If no zName is given, restore all system calls to their default
+ ** settings and return NULL
+ */
+ rc = SQLITE_OK;
+ for(i=0; i0 ){
+ memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
+ memcpy(zDbgBuf, zBuf, nMin);
+ osOutputDebugStringA(zDbgBuf);
+ }else{
+ osOutputDebugStringA(zBuf);
+ }
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+ memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
+ if ( osMultiByteToWideChar(
+ osAreFileApisANSI() ? CP_ACP : CP_OEMCP, 0, zBuf,
+ nMin, (LPWSTR)zDbgBuf, SQLITE_WIN32_DBG_BUF_SIZE/sizeof(WCHAR))<=0 ){
+ return;
+ }
+ osOutputDebugStringW((LPCWSTR)zDbgBuf);
+#else
+ if( nMin>0 ){
+ memset(zDbgBuf, 0, SQLITE_WIN32_DBG_BUF_SIZE);
+ memcpy(zDbgBuf, zBuf, nMin);
+ fprintf(stderr, "%s", zDbgBuf);
+ }else{
+ fprintf(stderr, "%s", zBuf);
+ }
+#endif
+}
+
+/*
+** The following routine suspends the current thread for at least ms
+** milliseconds. This is equivalent to the Win32 Sleep() interface.
+*/
+#if SQLITE_OS_WINRT
+static HANDLE sleepObj = NULL;
+#endif
+
+SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds){
+#if SQLITE_OS_WINRT
+ if ( sleepObj==NULL ){
+ sleepObj = osCreateEventExW(NULL, NULL, CREATE_EVENT_MANUAL_RESET,
+ SYNCHRONIZE);
+ }
+ assert( sleepObj!=NULL );
+ osWaitForSingleObjectEx(sleepObj, milliseconds, FALSE);
+#else
+ osSleep(milliseconds);
+#endif
+}
+
+/*
+** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
+** or WinCE. Return false (zero) for Win95, Win98, or WinME.
+**
+** Here is an interesting observation: Win95, Win98, and WinME lack
+** the LockFileEx() API. But we can still statically link against that
+** API as long as we don't call it when running Win95/98/ME. A call to
+** this routine is used to determine if the host is Win95/98/ME or
+** WinNT/2K/XP so that we will know whether or not we can safely call
+** the LockFileEx() API.
+*/
+
+#if !defined(SQLITE_WIN32_GETVERSIONEX) || !SQLITE_WIN32_GETVERSIONEX
+# define osIsNT() (1)
+#elif SQLITE_OS_WINCE || SQLITE_OS_WINRT || !defined(SQLITE_WIN32_HAS_ANSI)
+# define osIsNT() (1)
+#elif !defined(SQLITE_WIN32_HAS_WIDE)
+# define osIsNT() (0)
+#else
+ static int osIsNT(void){
+ if( sqlite3_os_type==0 ){
+#if defined(NTDDI_VERSION) && NTDDI_VERSION >= NTDDI_WIN8
+ OSVERSIONINFOW sInfo;
+ sInfo.dwOSVersionInfoSize = sizeof(sInfo);
+ osGetVersionExW(&sInfo);
+#else
+ OSVERSIONINFOA sInfo;
+ sInfo.dwOSVersionInfoSize = sizeof(sInfo);
+ osGetVersionExA(&sInfo);
+#endif
+ sqlite3_os_type = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
+ }
+ return sqlite3_os_type==2;
+ }
+#endif
+
+#ifdef SQLITE_WIN32_MALLOC
+/*
+** Allocate nBytes of memory.
+*/
+static void *winMemMalloc(int nBytes){
+ HANDLE hHeap;
+ void *p;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
+#endif
+ assert( nBytes>=0 );
+ p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
+ if( !p ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapAlloc %u bytes (%lu), heap=%p",
+ nBytes, osGetLastError(), (void*)hHeap);
+ }
+ return p;
+}
+
+/*
+** Free memory.
+*/
+static void winMemFree(void *pPrior){
+ HANDLE hHeap;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
+#endif
+ if( !pPrior ) return; /* Passing NULL to HeapFree is undefined. */
+ if( !osHeapFree(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapFree block %p (%lu), heap=%p",
+ pPrior, osGetLastError(), (void*)hHeap);
+ }
+}
+
+/*
+** Change the size of an existing memory allocation
+*/
+static void *winMemRealloc(void *pPrior, int nBytes){
+ HANDLE hHeap;
+ void *p;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior) );
+#endif
+ assert( nBytes>=0 );
+ if( !pPrior ){
+ p = osHeapAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, (SIZE_T)nBytes);
+ }else{
+ p = osHeapReAlloc(hHeap, SQLITE_WIN32_HEAP_FLAGS, pPrior, (SIZE_T)nBytes);
+ }
+ if( !p ){
+ sqlite3_log(SQLITE_NOMEM, "failed to %s %u bytes (%lu), heap=%p",
+ pPrior ? "HeapReAlloc" : "HeapAlloc", nBytes, osGetLastError(),
+ (void*)hHeap);
+ }
+ return p;
+}
+
+/*
+** Return the size of an outstanding allocation, in bytes.
+*/
+static int winMemSize(void *p){
+ HANDLE hHeap;
+ SIZE_T n;
+
+ winMemAssertMagic();
+ hHeap = winMemGetHeap();
+ assert( hHeap!=0 );
+ assert( hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(hHeap, SQLITE_WIN32_HEAP_FLAGS, p) );
+#endif
+ if( !p ) return 0;
+ n = osHeapSize(hHeap, SQLITE_WIN32_HEAP_FLAGS, p);
+ if( n==(SIZE_T)-1 ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapSize block %p (%lu), heap=%p",
+ p, osGetLastError(), (void*)hHeap);
+ return 0;
+ }
+ return (int)n;
+}
+
+/*
+** Round up a request size to the next valid allocation size.
+*/
+static int winMemRoundup(int n){
+ return n;
+}
+
+/*
+** Initialize this module.
+*/
+static int winMemInit(void *pAppData){
+ winMemData *pWinMemData = (winMemData *)pAppData;
+
+ if( !pWinMemData ) return SQLITE_ERROR;
+ assert( pWinMemData->magic1==WINMEM_MAGIC1 );
+ assert( pWinMemData->magic2==WINMEM_MAGIC2 );
+
+#if !SQLITE_OS_WINRT && SQLITE_WIN32_HEAP_CREATE
+ if( !pWinMemData->hHeap ){
+ DWORD dwInitialSize = SQLITE_WIN32_HEAP_INIT_SIZE;
+ DWORD dwMaximumSize = (DWORD)sqlite3GlobalConfig.nHeap;
+ if( dwMaximumSize==0 ){
+ dwMaximumSize = SQLITE_WIN32_HEAP_MAX_SIZE;
+ }else if( dwInitialSize>dwMaximumSize ){
+ dwInitialSize = dwMaximumSize;
+ }
+ pWinMemData->hHeap = osHeapCreate(SQLITE_WIN32_HEAP_FLAGS,
+ dwInitialSize, dwMaximumSize);
+ if( !pWinMemData->hHeap ){
+ sqlite3_log(SQLITE_NOMEM,
+ "failed to HeapCreate (%lu), flags=%u, initSize=%lu, maxSize=%lu",
+ osGetLastError(), SQLITE_WIN32_HEAP_FLAGS, dwInitialSize,
+ dwMaximumSize);
+ return SQLITE_NOMEM;
+ }
+ pWinMemData->bOwned = TRUE;
+ assert( pWinMemData->bOwned );
+ }
+#else
+ pWinMemData->hHeap = osGetProcessHeap();
+ if( !pWinMemData->hHeap ){
+ sqlite3_log(SQLITE_NOMEM,
+ "failed to GetProcessHeap (%lu)", osGetLastError());
+ return SQLITE_NOMEM;
+ }
+ pWinMemData->bOwned = FALSE;
+ assert( !pWinMemData->bOwned );
+#endif
+ assert( pWinMemData->hHeap!=0 );
+ assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
+#endif
+ return SQLITE_OK;
+}
+
+/*
+** Deinitialize this module.
+*/
+static void winMemShutdown(void *pAppData){
+ winMemData *pWinMemData = (winMemData *)pAppData;
+
+ if( !pWinMemData ) return;
+ assert( pWinMemData->magic1==WINMEM_MAGIC1 );
+ assert( pWinMemData->magic2==WINMEM_MAGIC2 );
+
+ if( pWinMemData->hHeap ){
+ assert( pWinMemData->hHeap!=INVALID_HANDLE_VALUE );
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_MALLOC_VALIDATE)
+ assert( osHeapValidate(pWinMemData->hHeap, SQLITE_WIN32_HEAP_FLAGS, NULL) );
+#endif
+ if( pWinMemData->bOwned ){
+ if( !osHeapDestroy(pWinMemData->hHeap) ){
+ sqlite3_log(SQLITE_NOMEM, "failed to HeapDestroy (%lu), heap=%p",
+ osGetLastError(), (void*)pWinMemData->hHeap);
+ }
+ pWinMemData->bOwned = FALSE;
+ }
+ pWinMemData->hHeap = NULL;
+ }
+}
+
+/*
+** Populate the low-level memory allocation function pointers in
+** sqlite3GlobalConfig.m with pointers to the routines in this file. The
+** arguments specify the block of memory to manage.
+**
+** This routine is only called by sqlite3_config(), and therefore
+** is not required to be threadsafe (it is not).
+*/
+SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetWin32(void){
+ static const sqlite3_mem_methods winMemMethods = {
+ winMemMalloc,
+ winMemFree,
+ winMemRealloc,
+ winMemSize,
+ winMemRoundup,
+ winMemInit,
+ winMemShutdown,
+ &win_mem_data
+ };
+ return &winMemMethods;
+}
+
+SQLITE_PRIVATE void sqlite3MemSetDefault(void){
+ sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetWin32());
+}
+#endif /* SQLITE_WIN32_MALLOC */
+
+/*
+** Convert a UTF-8 string to Microsoft Unicode (UTF-16?).
+**
+** Space to hold the returned string is obtained from malloc.
+*/
+static LPWSTR winUtf8ToUnicode(const char *zFilename){
+ int nChar;
+ LPWSTR zWideFilename;
+
+ nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
+ if( nChar==0 ){
+ return 0;
+ }
+ zWideFilename = sqlite3MallocZero( nChar*sizeof(zWideFilename[0]) );
+ if( zWideFilename==0 ){
+ return 0;
+ }
+ nChar = osMultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename,
+ nChar);
+ if( nChar==0 ){
+ sqlite3_free(zWideFilename);
+ zWideFilename = 0;
+ }
+ return zWideFilename;
+}
+
+/*
+** Convert Microsoft Unicode to UTF-8. Space to hold the returned string is
+** obtained from sqlite3_malloc().
+*/
+static char *winUnicodeToUtf8(LPCWSTR zWideFilename){
+ int nByte;
+ char *zFilename;
+
+ nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
+ if( nByte == 0 ){
+ return 0;
+ }
+ zFilename = sqlite3MallocZero( nByte );
+ if( zFilename==0 ){
+ return 0;
+ }
+ nByte = osWideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
+ 0, 0);
+ if( nByte == 0 ){
+ sqlite3_free(zFilename);
+ zFilename = 0;
+ }
+ return zFilename;
+}
+
+/*
+** Convert an ANSI string to Microsoft Unicode, based on the
+** current codepage settings for file apis.
+**
+** Space to hold the returned string is obtained
+** from sqlite3_malloc.
+*/
+static LPWSTR winMbcsToUnicode(const char *zFilename){
+ int nByte;
+ LPWSTR zMbcsFilename;
+ int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
+
+ nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, NULL,
+ 0)*sizeof(WCHAR);
+ if( nByte==0 ){
+ return 0;
+ }
+ zMbcsFilename = sqlite3MallocZero( nByte*sizeof(zMbcsFilename[0]) );
+ if( zMbcsFilename==0 ){
+ return 0;
+ }
+ nByte = osMultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename,
+ nByte);
+ if( nByte==0 ){
+ sqlite3_free(zMbcsFilename);
+ zMbcsFilename = 0;
+ }
+ return zMbcsFilename;
+}
+
+/*
+** Convert Microsoft Unicode to multi-byte character string, based on the
+** user's ANSI codepage.
+**
+** Space to hold the returned string is obtained from
+** sqlite3_malloc().
+*/
+static char *winUnicodeToMbcs(LPCWSTR zWideFilename){
+ int nByte;
+ char *zFilename;
+ int codepage = osAreFileApisANSI() ? CP_ACP : CP_OEMCP;
+
+ nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
+ if( nByte == 0 ){
+ return 0;
+ }
+ zFilename = sqlite3MallocZero( nByte );
+ if( zFilename==0 ){
+ return 0;
+ }
+ nByte = osWideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename,
+ nByte, 0, 0);
+ if( nByte == 0 ){
+ sqlite3_free(zFilename);
+ zFilename = 0;
+ }
+ return zFilename;
+}
+
+/*
+** Convert multibyte character string to UTF-8. Space to hold the
+** returned string is obtained from sqlite3_malloc().
+*/
+SQLITE_API char *sqlite3_win32_mbcs_to_utf8(const char *zFilename){
+ char *zFilenameUtf8;
+ LPWSTR zTmpWide;
+
+ zTmpWide = winMbcsToUnicode(zFilename);
+ if( zTmpWide==0 ){
+ return 0;
+ }
+ zFilenameUtf8 = winUnicodeToUtf8(zTmpWide);
+ sqlite3_free(zTmpWide);
+ return zFilenameUtf8;
+}
+
+/*
+** Convert UTF-8 to multibyte character string. Space to hold the
+** returned string is obtained from sqlite3_malloc().
+*/
+SQLITE_API char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){
+ char *zFilenameMbcs;
+ LPWSTR zTmpWide;
+
+ zTmpWide = winUtf8ToUnicode(zFilename);
+ if( zTmpWide==0 ){
+ return 0;
+ }
+ zFilenameMbcs = winUnicodeToMbcs(zTmpWide);
+ sqlite3_free(zTmpWide);
+ return zFilenameMbcs;
+}
+
+/*
+** This function sets the data directory or the temporary directory based on
+** the provided arguments. The type argument must be 1 in order to set the
+** data directory or 2 in order to set the temporary directory. The zValue
+** argument is the name of the directory to use. The return value will be
+** SQLITE_OK if successful.
+*/
+SQLITE_API int sqlite3_win32_set_directory(DWORD type, LPCWSTR zValue){
+ char **ppDirectory = 0;
+#ifndef SQLITE_OMIT_AUTOINIT
+ int rc = sqlite3_initialize();
+ if( rc ) return rc;
+#endif
+ if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
+ ppDirectory = &sqlite3_data_directory;
+ }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
+ ppDirectory = &sqlite3_temp_directory;
+ }
+ assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
+ || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
+ );
+ assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
+ if( ppDirectory ){
+ char *zValueUtf8 = 0;
+ if( zValue && zValue[0] ){
+ zValueUtf8 = winUnicodeToUtf8(zValue);
+ if ( zValueUtf8==0 ){
+ return SQLITE_NOMEM;
+ }
+ }
+ sqlite3_free(*ppDirectory);
+ *ppDirectory = zValueUtf8;
+ return SQLITE_OK;
+ }
+ return SQLITE_ERROR;
+}
+
+/*
+** The return value of winGetLastErrorMsg
+** is zero if the error message fits in the buffer, or non-zero
+** otherwise (if the message was truncated).
+*/
+static int winGetLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
+ /* FormatMessage returns 0 on failure. Otherwise it
+ ** returns the number of TCHARs written to the output
+ ** buffer, excluding the terminating null char.
+ */
+ DWORD dwLen = 0;
+ char *zOut = 0;
+
+ if( osIsNT() ){
+#if SQLITE_OS_WINRT
+ WCHAR zTempWide[SQLITE_WIN32_MAX_ERRMSG_CHARS+1];
+ dwLen = osFormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM |
+ FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL,
+ lastErrno,
+ 0,
+ zTempWide,
+ SQLITE_WIN32_MAX_ERRMSG_CHARS,
+ 0);
+#else
+ LPWSTR zTempWide = NULL;
+ dwLen = osFormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+ FORMAT_MESSAGE_FROM_SYSTEM |
+ FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL,
+ lastErrno,
+ 0,
+ (LPWSTR) &zTempWide,
+ 0,
+ 0);
+#endif
+ if( dwLen > 0 ){
+ /* allocate a buffer and convert to UTF8 */
+ sqlite3BeginBenignMalloc();
+ zOut = winUnicodeToUtf8(zTempWide);
+ sqlite3EndBenignMalloc();
+#if !SQLITE_OS_WINRT
+ /* free the system buffer allocated by FormatMessage */
+ osLocalFree(zTempWide);
+#endif
+ }
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ char *zTemp = NULL;
+ dwLen = osFormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+ FORMAT_MESSAGE_FROM_SYSTEM |
+ FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL,
+ lastErrno,
+ 0,
+ (LPSTR) &zTemp,
+ 0,
+ 0);
+ if( dwLen > 0 ){
+ /* allocate a buffer and convert to UTF8 */
+ sqlite3BeginBenignMalloc();
+ zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
+ sqlite3EndBenignMalloc();
+ /* free the system buffer allocated by FormatMessage */
+ osLocalFree(zTemp);
+ }
+ }
+#endif
+ if( 0 == dwLen ){
+ sqlite3_snprintf(nBuf, zBuf, "OsError 0x%lx (%lu)", lastErrno, lastErrno);
+ }else{
+ /* copy a maximum of nBuf chars to output buffer */
+ sqlite3_snprintf(nBuf, zBuf, "%s", zOut);
+ /* free the UTF8 buffer */
+ sqlite3_free(zOut);
+ }
+ return 0;
+}
+
+/*
+**
+** This function - winLogErrorAtLine() - is only ever called via the macro
+** winLogError().
+**
+** This routine is invoked after an error occurs in an OS function.
+** It logs a message using sqlite3_log() containing the current value of
+** error code and, if possible, the human-readable equivalent from
+** FormatMessage.
+**
+** The first argument passed to the macro should be the error code that
+** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN).
+** The two subsequent arguments should be the name of the OS function that
+** failed and the associated file-system path, if any.
+*/
+#define winLogError(a,b,c,d) winLogErrorAtLine(a,b,c,d,__LINE__)
+static int winLogErrorAtLine(
+ int errcode, /* SQLite error code */
+ DWORD lastErrno, /* Win32 last error */
+ const char *zFunc, /* Name of OS function that failed */
+ const char *zPath, /* File path associated with error */
+ int iLine /* Source line number where error occurred */
+){
+ char zMsg[500]; /* Human readable error text */
+ int i; /* Loop counter */
+
+ zMsg[0] = 0;
+ winGetLastErrorMsg(lastErrno, sizeof(zMsg), zMsg);
+ assert( errcode!=SQLITE_OK );
+ if( zPath==0 ) zPath = "";
+ for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
+ zMsg[i] = 0;
+ sqlite3_log(errcode,
+ "os_win.c:%d: (%lu) %s(%s) - %s",
+ iLine, lastErrno, zFunc, zPath, zMsg
+ );
+
+ return errcode;
+}
+
+/*
+** The number of times that a ReadFile(), WriteFile(), and DeleteFile()
+** will be retried following a locking error - probably caused by
+** antivirus software. Also the initial delay before the first retry.
+** The delay increases linearly with each retry.
+*/
+#ifndef SQLITE_WIN32_IOERR_RETRY
+# define SQLITE_WIN32_IOERR_RETRY 10
+#endif
+#ifndef SQLITE_WIN32_IOERR_RETRY_DELAY
+# define SQLITE_WIN32_IOERR_RETRY_DELAY 25
+#endif
+static int winIoerrRetry = SQLITE_WIN32_IOERR_RETRY;
+static int winIoerrRetryDelay = SQLITE_WIN32_IOERR_RETRY_DELAY;
+
+/*
+** The "winIoerrCanRetry1" macro is used to determine if a particular I/O
+** error code obtained via GetLastError() is eligible to be retried. It
+** must accept the error code DWORD as its only argument and should return
+** non-zero if the error code is transient in nature and the operation
+** responsible for generating the original error might succeed upon being
+** retried. The argument to this macro should be a variable.
+**
+** Additionally, a macro named "winIoerrCanRetry2" may be defined. If it
+** is defined, it will be consulted only when the macro "winIoerrCanRetry1"
+** returns zero. The "winIoerrCanRetry2" macro is completely optional and
+** may be used to include additional error codes in the set that should
+** result in the failing I/O operation being retried by the caller. If
+** defined, the "winIoerrCanRetry2" macro must exhibit external semantics
+** identical to those of the "winIoerrCanRetry1" macro.
+*/
+#if !defined(winIoerrCanRetry1)
+#define winIoerrCanRetry1(a) (((a)==ERROR_ACCESS_DENIED) || \
+ ((a)==ERROR_SHARING_VIOLATION) || \
+ ((a)==ERROR_LOCK_VIOLATION) || \
+ ((a)==ERROR_DEV_NOT_EXIST) || \
+ ((a)==ERROR_NETNAME_DELETED) || \
+ ((a)==ERROR_SEM_TIMEOUT) || \
+ ((a)==ERROR_NETWORK_UNREACHABLE))
+#endif
+
+/*
+** If a ReadFile() or WriteFile() error occurs, invoke this routine
+** to see if it should be retried. Return TRUE to retry. Return FALSE
+** to give up with an error.
+*/
+static int winRetryIoerr(int *pnRetry, DWORD *pError){
+ DWORD e = osGetLastError();
+ if( *pnRetry>=winIoerrRetry ){
+ if( pError ){
+ *pError = e;
+ }
+ return 0;
+ }
+ if( winIoerrCanRetry1(e) ){
+ sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
+ ++*pnRetry;
+ return 1;
+ }
+#if defined(winIoerrCanRetry2)
+ else if( winIoerrCanRetry2(e) ){
+ sqlite3_win32_sleep(winIoerrRetryDelay*(1+*pnRetry));
+ ++*pnRetry;
+ return 1;
+ }
+#endif
+ if( pError ){
+ *pError = e;
+ }
+ return 0;
+}
+
+/*
+** Log a I/O error retry episode.
+*/
+static void winLogIoerr(int nRetry){
+ if( nRetry ){
+ sqlite3_log(SQLITE_IOERR,
+ "delayed %dms for lock/sharing conflict",
+ winIoerrRetryDelay*nRetry*(nRetry+1)/2
+ );
+ }
+}
+
+#if SQLITE_OS_WINCE
+/*************************************************************************
+** This section contains code for WinCE only.
+*/
+#if !defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API
+/*
+** The MSVC CRT on Windows CE may not have a localtime() function. So
+** create a substitute.
+*/
+/* #include */
+struct tm *__cdecl localtime(const time_t *t)
+{
+ static struct tm y;
+ FILETIME uTm, lTm;
+ SYSTEMTIME pTm;
+ sqlite3_int64 t64;
+ t64 = *t;
+ t64 = (t64 + 11644473600)*10000000;
+ uTm.dwLowDateTime = (DWORD)(t64 & 0xFFFFFFFF);
+ uTm.dwHighDateTime= (DWORD)(t64 >> 32);
+ osFileTimeToLocalFileTime(&uTm,&lTm);
+ osFileTimeToSystemTime(&lTm,&pTm);
+ y.tm_year = pTm.wYear - 1900;
+ y.tm_mon = pTm.wMonth - 1;
+ y.tm_wday = pTm.wDayOfWeek;
+ y.tm_mday = pTm.wDay;
+ y.tm_hour = pTm.wHour;
+ y.tm_min = pTm.wMinute;
+ y.tm_sec = pTm.wSecond;
+ return &y;
+}
+#endif
+
+#define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
+
+/*
+** Acquire a lock on the handle h
+*/
+static void winceMutexAcquire(HANDLE h){
+ DWORD dwErr;
+ do {
+ dwErr = osWaitForSingleObject(h, INFINITE);
+ } while (dwErr != WAIT_OBJECT_0 && dwErr != WAIT_ABANDONED);
+}
+/*
+** Release a lock acquired by winceMutexAcquire()
+*/
+#define winceMutexRelease(h) ReleaseMutex(h)
+
+/*
+** Create the mutex and shared memory used for locking in the file
+** descriptor pFile
+*/
+static int winceCreateLock(const char *zFilename, winFile *pFile){
+ LPWSTR zTok;
+ LPWSTR zName;
+ DWORD lastErrno;
+ BOOL bLogged = FALSE;
+ BOOL bInit = TRUE;
+
+ zName = winUtf8ToUnicode(zFilename);
+ if( zName==0 ){
+ /* out of memory */
+ return SQLITE_IOERR_NOMEM;
+ }
+
+ /* Initialize the local lockdata */
+ memset(&pFile->local, 0, sizeof(pFile->local));
+
+ /* Replace the backslashes from the filename and lowercase it
+ ** to derive a mutex name. */
+ zTok = osCharLowerW(zName);
+ for (;*zTok;zTok++){
+ if (*zTok == '\\') *zTok = '_';
+ }
+
+ /* Create/open the named mutex */
+ pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
+ if (!pFile->hMutex){
+ pFile->lastErrno = osGetLastError();
+ sqlite3_free(zName);
+ return winLogError(SQLITE_IOERR, pFile->lastErrno,
+ "winceCreateLock1", zFilename);
+ }
+
+ /* Acquire the mutex before continuing */
+ winceMutexAcquire(pFile->hMutex);
+
+ /* Since the names of named mutexes, semaphores, file mappings etc are
+ ** case-sensitive, take advantage of that by uppercasing the mutex name
+ ** and using that as the shared filemapping name.
+ */
+ osCharUpperW(zName);
+ pFile->hShared = osCreateFileMappingW(INVALID_HANDLE_VALUE, NULL,
+ PAGE_READWRITE, 0, sizeof(winceLock),
+ zName);
+
+ /* Set a flag that indicates we're the first to create the memory so it
+ ** must be zero-initialized */
+ lastErrno = osGetLastError();
+ if (lastErrno == ERROR_ALREADY_EXISTS){
+ bInit = FALSE;
+ }
+
+ sqlite3_free(zName);
+
+ /* If we succeeded in making the shared memory handle, map it. */
+ if( pFile->hShared ){
+ pFile->shared = (winceLock*)osMapViewOfFile(pFile->hShared,
+ FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
+ /* If mapping failed, close the shared memory handle and erase it */
+ if( !pFile->shared ){
+ pFile->lastErrno = osGetLastError();
+ winLogError(SQLITE_IOERR, pFile->lastErrno,
+ "winceCreateLock2", zFilename);
+ bLogged = TRUE;
+ osCloseHandle(pFile->hShared);
+ pFile->hShared = NULL;
+ }
+ }
+
+ /* If shared memory could not be created, then close the mutex and fail */
+ if( pFile->hShared==NULL ){
+ if( !bLogged ){
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_IOERR, pFile->lastErrno,
+ "winceCreateLock3", zFilename);
+ bLogged = TRUE;
+ }
+ winceMutexRelease(pFile->hMutex);
+ osCloseHandle(pFile->hMutex);
+ pFile->hMutex = NULL;
+ return SQLITE_IOERR;
+ }
+
+ /* Initialize the shared memory if we're supposed to */
+ if( bInit ){
+ memset(pFile->shared, 0, sizeof(winceLock));
+ }
+
+ winceMutexRelease(pFile->hMutex);
+ return SQLITE_OK;
+}
+
+/*
+** Destroy the part of winFile that deals with wince locks
+*/
+static void winceDestroyLock(winFile *pFile){
+ if (pFile->hMutex){
+ /* Acquire the mutex */
+ winceMutexAcquire(pFile->hMutex);
+
+ /* The following blocks should probably assert in debug mode, but they
+ are to cleanup in case any locks remained open */
+ if (pFile->local.nReaders){
+ pFile->shared->nReaders --;
+ }
+ if (pFile->local.bReserved){
+ pFile->shared->bReserved = FALSE;
+ }
+ if (pFile->local.bPending){
+ pFile->shared->bPending = FALSE;
+ }
+ if (pFile->local.bExclusive){
+ pFile->shared->bExclusive = FALSE;
+ }
+
+ /* De-reference and close our copy of the shared memory handle */
+ osUnmapViewOfFile(pFile->shared);
+ osCloseHandle(pFile->hShared);
+
+ /* Done with the mutex */
+ winceMutexRelease(pFile->hMutex);
+ osCloseHandle(pFile->hMutex);
+ pFile->hMutex = NULL;
+ }
+}
+
+/*
+** An implementation of the LockFile() API of Windows for CE
+*/
+static BOOL winceLockFile(
+ LPHANDLE phFile,
+ DWORD dwFileOffsetLow,
+ DWORD dwFileOffsetHigh,
+ DWORD nNumberOfBytesToLockLow,
+ DWORD nNumberOfBytesToLockHigh
+){
+ winFile *pFile = HANDLE_TO_WINFILE(phFile);
+ BOOL bReturn = FALSE;
+
+ UNUSED_PARAMETER(dwFileOffsetHigh);
+ UNUSED_PARAMETER(nNumberOfBytesToLockHigh);
+
+ if (!pFile->hMutex) return TRUE;
+ winceMutexAcquire(pFile->hMutex);
+
+ /* Wanting an exclusive lock? */
+ if (dwFileOffsetLow == (DWORD)SHARED_FIRST
+ && nNumberOfBytesToLockLow == (DWORD)SHARED_SIZE){
+ if (pFile->shared->nReaders == 0 && pFile->shared->bExclusive == 0){
+ pFile->shared->bExclusive = TRUE;
+ pFile->local.bExclusive = TRUE;
+ bReturn = TRUE;
+ }
+ }
+
+ /* Want a read-only lock? */
+ else if (dwFileOffsetLow == (DWORD)SHARED_FIRST &&
+ nNumberOfBytesToLockLow == 1){
+ if (pFile->shared->bExclusive == 0){
+ pFile->local.nReaders ++;
+ if (pFile->local.nReaders == 1){
+ pFile->shared->nReaders ++;
+ }
+ bReturn = TRUE;
+ }
+ }
+
+ /* Want a pending lock? */
+ else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
+ && nNumberOfBytesToLockLow == 1){
+ /* If no pending lock has been acquired, then acquire it */
+ if (pFile->shared->bPending == 0) {
+ pFile->shared->bPending = TRUE;
+ pFile->local.bPending = TRUE;
+ bReturn = TRUE;
+ }
+ }
+
+ /* Want a reserved lock? */
+ else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
+ && nNumberOfBytesToLockLow == 1){
+ if (pFile->shared->bReserved == 0) {
+ pFile->shared->bReserved = TRUE;
+ pFile->local.bReserved = TRUE;
+ bReturn = TRUE;
+ }
+ }
+
+ winceMutexRelease(pFile->hMutex);
+ return bReturn;
+}
+
+/*
+** An implementation of the UnlockFile API of Windows for CE
+*/
+static BOOL winceUnlockFile(
+ LPHANDLE phFile,
+ DWORD dwFileOffsetLow,
+ DWORD dwFileOffsetHigh,
+ DWORD nNumberOfBytesToUnlockLow,
+ DWORD nNumberOfBytesToUnlockHigh
+){
+ winFile *pFile = HANDLE_TO_WINFILE(phFile);
+ BOOL bReturn = FALSE;
+
+ UNUSED_PARAMETER(dwFileOffsetHigh);
+ UNUSED_PARAMETER(nNumberOfBytesToUnlockHigh);
+
+ if (!pFile->hMutex) return TRUE;
+ winceMutexAcquire(pFile->hMutex);
+
+ /* Releasing a reader lock or an exclusive lock */
+ if (dwFileOffsetLow == (DWORD)SHARED_FIRST){
+ /* Did we have an exclusive lock? */
+ if (pFile->local.bExclusive){
+ assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE);
+ pFile->local.bExclusive = FALSE;
+ pFile->shared->bExclusive = FALSE;
+ bReturn = TRUE;
+ }
+
+ /* Did we just have a reader lock? */
+ else if (pFile->local.nReaders){
+ assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE
+ || nNumberOfBytesToUnlockLow == 1);
+ pFile->local.nReaders --;
+ if (pFile->local.nReaders == 0)
+ {
+ pFile->shared->nReaders --;
+ }
+ bReturn = TRUE;
+ }
+ }
+
+ /* Releasing a pending lock */
+ else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
+ && nNumberOfBytesToUnlockLow == 1){
+ if (pFile->local.bPending){
+ pFile->local.bPending = FALSE;
+ pFile->shared->bPending = FALSE;
+ bReturn = TRUE;
+ }
+ }
+ /* Releasing a reserved lock */
+ else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
+ && nNumberOfBytesToUnlockLow == 1){
+ if (pFile->local.bReserved) {
+ pFile->local.bReserved = FALSE;
+ pFile->shared->bReserved = FALSE;
+ bReturn = TRUE;
+ }
+ }
+
+ winceMutexRelease(pFile->hMutex);
+ return bReturn;
+}
+/*
+** End of the special code for wince
+*****************************************************************************/
+#endif /* SQLITE_OS_WINCE */
+
+/*
+** Lock a file region.
+*/
+static BOOL winLockFile(
+ LPHANDLE phFile,
+ DWORD flags,
+ DWORD offsetLow,
+ DWORD offsetHigh,
+ DWORD numBytesLow,
+ DWORD numBytesHigh
+){
+#if SQLITE_OS_WINCE
+ /*
+ ** NOTE: Windows CE is handled differently here due its lack of the Win32
+ ** API LockFile.
+ */
+ return winceLockFile(phFile, offsetLow, offsetHigh,
+ numBytesLow, numBytesHigh);
+#else
+ if( osIsNT() ){
+ OVERLAPPED ovlp;
+ memset(&ovlp, 0, sizeof(OVERLAPPED));
+ ovlp.Offset = offsetLow;
+ ovlp.OffsetHigh = offsetHigh;
+ return osLockFileEx(*phFile, flags, 0, numBytesLow, numBytesHigh, &ovlp);
+ }else{
+ return osLockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
+ numBytesHigh);
+ }
+#endif
+}
+
+/*
+** Unlock a file region.
+ */
+static BOOL winUnlockFile(
+ LPHANDLE phFile,
+ DWORD offsetLow,
+ DWORD offsetHigh,
+ DWORD numBytesLow,
+ DWORD numBytesHigh
+){
+#if SQLITE_OS_WINCE
+ /*
+ ** NOTE: Windows CE is handled differently here due its lack of the Win32
+ ** API UnlockFile.
+ */
+ return winceUnlockFile(phFile, offsetLow, offsetHigh,
+ numBytesLow, numBytesHigh);
+#else
+ if( osIsNT() ){
+ OVERLAPPED ovlp;
+ memset(&ovlp, 0, sizeof(OVERLAPPED));
+ ovlp.Offset = offsetLow;
+ ovlp.OffsetHigh = offsetHigh;
+ return osUnlockFileEx(*phFile, 0, numBytesLow, numBytesHigh, &ovlp);
+ }else{
+ return osUnlockFile(*phFile, offsetLow, offsetHigh, numBytesLow,
+ numBytesHigh);
+ }
+#endif
+}
+
+/*****************************************************************************
+** The next group of routines implement the I/O methods specified
+** by the sqlite3_io_methods object.
+******************************************************************************/
+
+/*
+** Some Microsoft compilers lack this definition.
+*/
+#ifndef INVALID_SET_FILE_POINTER
+# define INVALID_SET_FILE_POINTER ((DWORD)-1)
+#endif
+
+/*
+** Move the current position of the file handle passed as the first
+** argument to offset iOffset within the file. If successful, return 0.
+** Otherwise, set pFile->lastErrno and return non-zero.
+*/
+static int winSeekFile(winFile *pFile, sqlite3_int64 iOffset){
+#if !SQLITE_OS_WINRT
+ LONG upperBits; /* Most sig. 32 bits of new offset */
+ LONG lowerBits; /* Least sig. 32 bits of new offset */
+ DWORD dwRet; /* Value returned by SetFilePointer() */
+ DWORD lastErrno; /* Value returned by GetLastError() */
+
+ OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
+
+ upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
+ lowerBits = (LONG)(iOffset & 0xffffffff);
+
+ /* API oddity: If successful, SetFilePointer() returns a dword
+ ** containing the lower 32-bits of the new file-offset. Or, if it fails,
+ ** it returns INVALID_SET_FILE_POINTER. However according to MSDN,
+ ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine
+ ** whether an error has actually occurred, it is also necessary to call
+ ** GetLastError().
+ */
+ dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+
+ if( (dwRet==INVALID_SET_FILE_POINTER
+ && ((lastErrno = osGetLastError())!=NO_ERROR)) ){
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
+ "winSeekFile", pFile->zPath);
+ OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
+ return 1;
+ }
+
+ OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
+ return 0;
+#else
+ /*
+ ** Same as above, except that this implementation works for WinRT.
+ */
+
+ LARGE_INTEGER x; /* The new offset */
+ BOOL bRet; /* Value returned by SetFilePointerEx() */
+
+ x.QuadPart = iOffset;
+ bRet = osSetFilePointerEx(pFile->h, x, 0, FILE_BEGIN);
+
+ if(!bRet){
+ pFile->lastErrno = osGetLastError();
+ winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
+ "winSeekFile", pFile->zPath);
+ OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
+ return 1;
+ }
+
+ OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
+ return 0;
+#endif
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/* Forward references to VFS helper methods used for memory mapped files */
+static int winMapfile(winFile*, sqlite3_int64);
+static int winUnmapfile(winFile*);
+#endif
+
+/*
+** Close a file.
+**
+** It is reported that an attempt to close a handle might sometimes
+** fail. This is a very unreasonable result, but Windows is notorious
+** for being unreasonable so I do not doubt that it might happen. If
+** the close fails, we pause for 100 milliseconds and try again. As
+** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
+** giving up and returning an error.
+*/
+#define MX_CLOSE_ATTEMPT 3
+static int winClose(sqlite3_file *id){
+ int rc, cnt = 0;
+ winFile *pFile = (winFile*)id;
+
+ assert( id!=0 );
+#ifndef SQLITE_OMIT_WAL
+ assert( pFile->pShm==0 );
+#endif
+ assert( pFile->h!=NULL && pFile->h!=INVALID_HANDLE_VALUE );
+ OSTRACE(("CLOSE file=%p\n", pFile->h));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ winUnmapfile(pFile);
+#endif
+
+ do{
+ rc = osCloseHandle(pFile->h);
+ /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
+ }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (sqlite3_win32_sleep(100), 1) );
+#if SQLITE_OS_WINCE
+#define WINCE_DELETION_ATTEMPTS 3
+ winceDestroyLock(pFile);
+ if( pFile->zDeleteOnClose ){
+ int cnt = 0;
+ while(
+ osDeleteFileW(pFile->zDeleteOnClose)==0
+ && osGetFileAttributesW(pFile->zDeleteOnClose)!=0xffffffff
+ && cnt++ < WINCE_DELETION_ATTEMPTS
+ ){
+ sqlite3_win32_sleep(100); /* Wait a little before trying again */
+ }
+ sqlite3_free(pFile->zDeleteOnClose);
+ }
+#endif
+ if( rc ){
+ pFile->h = NULL;
+ }
+ OpenCounter(-1);
+ OSTRACE(("CLOSE file=%p, rc=%s\n", pFile->h, rc ? "ok" : "failed"));
+ return rc ? SQLITE_OK
+ : winLogError(SQLITE_IOERR_CLOSE, osGetLastError(),
+ "winClose", pFile->zPath);
+}
+
+/*
+** Read data from a file into a buffer. Return SQLITE_OK if all
+** bytes were read successfully and SQLITE_IOERR if anything goes
+** wrong.
+*/
+static int winRead(
+ sqlite3_file *id, /* File to read from */
+ void *pBuf, /* Write content into this buffer */
+ int amt, /* Number of bytes to read */
+ sqlite3_int64 offset /* Begin reading at this offset */
+){
+#if !SQLITE_OS_WINCE
+ OVERLAPPED overlapped; /* The offset for ReadFile. */
+#endif
+ winFile *pFile = (winFile*)id; /* file handle */
+ DWORD nRead; /* Number of bytes actually read from file */
+ int nRetry = 0; /* Number of retrys */
+
+ assert( id!=0 );
+ assert( amt>0 );
+ assert( offset>=0 );
+ SimulateIOError(return SQLITE_IOERR_READ);
+ OSTRACE(("READ file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
+ pFile->h, pBuf, amt, offset, pFile->locktype));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this read request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
+ OSTRACE(("READ-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }else{
+ int nCopy = (int)(pFile->mmapSize - offset);
+ memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+#if SQLITE_OS_WINCE
+ if( winSeekFile(pFile, offset) ){
+ OSTRACE(("READ file=%p, rc=SQLITE_FULL\n", pFile->h));
+ return SQLITE_FULL;
+ }
+ while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
+#else
+ memset(&overlapped, 0, sizeof(OVERLAPPED));
+ overlapped.Offset = (LONG)(offset & 0xffffffff);
+ overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
+ while( !osReadFile(pFile->h, pBuf, amt, &nRead, &overlapped) &&
+ osGetLastError()!=ERROR_HANDLE_EOF ){
+#endif
+ DWORD lastErrno;
+ if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
+ pFile->lastErrno = lastErrno;
+ OSTRACE(("READ file=%p, rc=SQLITE_IOERR_READ\n", pFile->h));
+ return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
+ "winRead", pFile->zPath);
+ }
+ winLogIoerr(nRetry);
+ if( nRead<(DWORD)amt ){
+ /* Unread parts of the buffer must be zero-filled */
+ memset(&((char*)pBuf)[nRead], 0, amt-nRead);
+ OSTRACE(("READ file=%p, rc=SQLITE_IOERR_SHORT_READ\n", pFile->h));
+ return SQLITE_IOERR_SHORT_READ;
+ }
+
+ OSTRACE(("READ file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+}
+
+/*
+** Write data from a buffer into a file. Return SQLITE_OK on success
+** or some other error code on failure.
+*/
+static int winWrite(
+ sqlite3_file *id, /* File to write into */
+ const void *pBuf, /* The bytes to be written */
+ int amt, /* Number of bytes to write */
+ sqlite3_int64 offset /* Offset into the file to begin writing at */
+){
+ int rc = 0; /* True if error has occurred, else false */
+ winFile *pFile = (winFile*)id; /* File handle */
+ int nRetry = 0; /* Number of retries */
+
+ assert( amt>0 );
+ assert( pFile );
+ SimulateIOError(return SQLITE_IOERR_WRITE);
+ SimulateDiskfullError(return SQLITE_FULL);
+
+ OSTRACE(("WRITE file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
+ pFile->h, pBuf, amt, offset, pFile->locktype));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* Deal with as much of this write request as possible by transfering
+ ** data from the memory mapping using memcpy(). */
+ if( offsetmmapSize ){
+ if( offset+amt <= pFile->mmapSize ){
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
+ OSTRACE(("WRITE-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }else{
+ int nCopy = (int)(pFile->mmapSize - offset);
+ memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
+ pBuf = &((u8 *)pBuf)[nCopy];
+ amt -= nCopy;
+ offset += nCopy;
+ }
+ }
+#endif
+
+#if SQLITE_OS_WINCE
+ rc = winSeekFile(pFile, offset);
+ if( rc==0 ){
+#else
+ {
+#endif
+#if !SQLITE_OS_WINCE
+ OVERLAPPED overlapped; /* The offset for WriteFile. */
+#endif
+ u8 *aRem = (u8 *)pBuf; /* Data yet to be written */
+ int nRem = amt; /* Number of bytes yet to be written */
+ DWORD nWrite; /* Bytes written by each WriteFile() call */
+ DWORD lastErrno = NO_ERROR; /* Value returned by GetLastError() */
+
+#if !SQLITE_OS_WINCE
+ memset(&overlapped, 0, sizeof(OVERLAPPED));
+ overlapped.Offset = (LONG)(offset & 0xffffffff);
+ overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
+#endif
+
+ while( nRem>0 ){
+#if SQLITE_OS_WINCE
+ if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, 0) ){
+#else
+ if( !osWriteFile(pFile->h, aRem, nRem, &nWrite, &overlapped) ){
+#endif
+ if( winRetryIoerr(&nRetry, &lastErrno) ) continue;
+ break;
+ }
+ assert( nWrite==0 || nWrite<=(DWORD)nRem );
+ if( nWrite==0 || nWrite>(DWORD)nRem ){
+ lastErrno = osGetLastError();
+ break;
+ }
+#if !SQLITE_OS_WINCE
+ offset += nWrite;
+ overlapped.Offset = (LONG)(offset & 0xffffffff);
+ overlapped.OffsetHigh = (LONG)((offset>>32) & 0x7fffffff);
+#endif
+ aRem += nWrite;
+ nRem -= nWrite;
+ }
+ if( nRem>0 ){
+ pFile->lastErrno = lastErrno;
+ rc = 1;
+ }
+ }
+
+ if( rc ){
+ if( ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
+ || ( pFile->lastErrno==ERROR_DISK_FULL )){
+ OSTRACE(("WRITE file=%p, rc=SQLITE_FULL\n", pFile->h));
+ return winLogError(SQLITE_FULL, pFile->lastErrno,
+ "winWrite1", pFile->zPath);
+ }
+ OSTRACE(("WRITE file=%p, rc=SQLITE_IOERR_WRITE\n", pFile->h));
+ return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
+ "winWrite2", pFile->zPath);
+ }else{
+ winLogIoerr(nRetry);
+ }
+ OSTRACE(("WRITE file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+}
+
+/*
+** Truncate an open file to a specified size
+*/
+static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
+ winFile *pFile = (winFile*)id; /* File handle object */
+ int rc = SQLITE_OK; /* Return code for this function */
+ DWORD lastErrno;
+
+ assert( pFile );
+ SimulateIOError(return SQLITE_IOERR_TRUNCATE);
+ OSTRACE(("TRUNCATE file=%p, size=%lld, lock=%d\n",
+ pFile->h, nByte, pFile->locktype));
+
+ /* If the user has configured a chunk-size for this file, truncate the
+ ** file so that it consists of an integer number of chunks (i.e. the
+ ** actual file size after the operation may be larger than the requested
+ ** size).
+ */
+ if( pFile->szChunk>0 ){
+ nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+ }
+
+ /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
+ if( winSeekFile(pFile, nByte) ){
+ rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
+ "winTruncate1", pFile->zPath);
+ }else if( 0==osSetEndOfFile(pFile->h) &&
+ ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
+ pFile->lastErrno = lastErrno;
+ rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
+ "winTruncate2", pFile->zPath);
+ }
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ /* If the file was truncated to a size smaller than the currently
+ ** mapped region, reduce the effective mapping size as well. SQLite will
+ ** use read() and write() to access data beyond this point from now on.
+ */
+ if( pFile->pMapRegion && nBytemmapSize ){
+ pFile->mmapSize = nByte;
+ }
+#endif
+
+ OSTRACE(("TRUNCATE file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
+ return rc;
+}
+
+#ifdef SQLITE_TEST
+/*
+** Count the number of fullsyncs and normal syncs. This is used to test
+** that syncs and fullsyncs are occuring at the right times.
+*/
+SQLITE_API int sqlite3_sync_count = 0;
+SQLITE_API int sqlite3_fullsync_count = 0;
+#endif
+
+/*
+** Make sure all writes to a particular file are committed to disk.
+*/
+static int winSync(sqlite3_file *id, int flags){
+#ifndef SQLITE_NO_SYNC
+ /*
+ ** Used only when SQLITE_NO_SYNC is not defined.
+ */
+ BOOL rc;
+#endif
+#if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || \
+ (defined(SQLITE_TEST) && defined(SQLITE_DEBUG))
+ /*
+ ** Used when SQLITE_NO_SYNC is not defined and by the assert() and/or
+ ** OSTRACE() macros.
+ */
+ winFile *pFile = (winFile*)id;
+#else
+ UNUSED_PARAMETER(id);
+#endif
+
+ assert( pFile );
+ /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
+ assert((flags&0x0F)==SQLITE_SYNC_NORMAL
+ || (flags&0x0F)==SQLITE_SYNC_FULL
+ );
+
+ /* Unix cannot, but some systems may return SQLITE_FULL from here. This
+ ** line is to test that doing so does not cause any problems.
+ */
+ SimulateDiskfullError( return SQLITE_FULL );
+
+ OSTRACE(("SYNC file=%p, flags=%x, lock=%d\n",
+ pFile->h, flags, pFile->locktype));
+
+#ifndef SQLITE_TEST
+ UNUSED_PARAMETER(flags);
+#else
+ if( (flags&0x0F)==SQLITE_SYNC_FULL ){
+ sqlite3_fullsync_count++;
+ }
+ sqlite3_sync_count++;
+#endif
+
+ /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
+ ** no-op
+ */
+#ifdef SQLITE_NO_SYNC
+ OSTRACE(("SYNC-NOP file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+#else
+ rc = osFlushFileBuffers(pFile->h);
+ SimulateIOError( rc=FALSE );
+ if( rc ){
+ OSTRACE(("SYNC file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }else{
+ pFile->lastErrno = osGetLastError();
+ OSTRACE(("SYNC file=%p, rc=SQLITE_IOERR_FSYNC\n", pFile->h));
+ return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
+ "winSync", pFile->zPath);
+ }
+#endif
+}
+
+/*
+** Determine the current size of a file in bytes
+*/
+static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
+ winFile *pFile = (winFile*)id;
+ int rc = SQLITE_OK;
+
+ assert( id!=0 );
+ assert( pSize!=0 );
+ SimulateIOError(return SQLITE_IOERR_FSTAT);
+ OSTRACE(("SIZE file=%p, pSize=%p\n", pFile->h, pSize));
+
+#if SQLITE_OS_WINRT
+ {
+ FILE_STANDARD_INFO info;
+ if( osGetFileInformationByHandleEx(pFile->h, FileStandardInfo,
+ &info, sizeof(info)) ){
+ *pSize = info.EndOfFile.QuadPart;
+ }else{
+ pFile->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
+ "winFileSize", pFile->zPath);
+ }
+ }
+#else
+ {
+ DWORD upperBits;
+ DWORD lowerBits;
+ DWORD lastErrno;
+
+ lowerBits = osGetFileSize(pFile->h, &upperBits);
+ *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
+ if( (lowerBits == INVALID_FILE_SIZE)
+ && ((lastErrno = osGetLastError())!=NO_ERROR) ){
+ pFile->lastErrno = lastErrno;
+ rc = winLogError(SQLITE_IOERR_FSTAT, pFile->lastErrno,
+ "winFileSize", pFile->zPath);
+ }
+ }
+#endif
+ OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
+ pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
+*/
+#ifndef LOCKFILE_FAIL_IMMEDIATELY
+# define LOCKFILE_FAIL_IMMEDIATELY 1
+#endif
+
+#ifndef LOCKFILE_EXCLUSIVE_LOCK
+# define LOCKFILE_EXCLUSIVE_LOCK 2
+#endif
+
+/*
+** Historically, SQLite has used both the LockFile and LockFileEx functions.
+** When the LockFile function was used, it was always expected to fail
+** immediately if the lock could not be obtained. Also, it always expected to
+** obtain an exclusive lock. These flags are used with the LockFileEx function
+** and reflect those expectations; therefore, they should not be changed.
+*/
+#ifndef SQLITE_LOCKFILE_FLAGS
+# define SQLITE_LOCKFILE_FLAGS (LOCKFILE_FAIL_IMMEDIATELY | \
+ LOCKFILE_EXCLUSIVE_LOCK)
+#endif
+
+/*
+** Currently, SQLite never calls the LockFileEx function without wanting the
+** call to fail immediately if the lock cannot be obtained.
+*/
+#ifndef SQLITE_LOCKFILEEX_FLAGS
+# define SQLITE_LOCKFILEEX_FLAGS (LOCKFILE_FAIL_IMMEDIATELY)
+#endif
+
+/*
+** Acquire a reader lock.
+** Different API routines are called depending on whether or not this
+** is Win9x or WinNT.
+*/
+static int winGetReadLock(winFile *pFile){
+ int res;
+ OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
+ if( osIsNT() ){
+#if SQLITE_OS_WINCE
+ /*
+ ** NOTE: Windows CE is handled differently here due its lack of the Win32
+ ** API LockFileEx.
+ */
+ res = winceLockFile(&pFile->h, SHARED_FIRST, 0, 1, 0);
+#else
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS, SHARED_FIRST, 0,
+ SHARED_SIZE, 0);
+#endif
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ int lk;
+ sqlite3_randomness(sizeof(lk), &lk);
+ pFile->sharedLockByte = (short)((lk & 0x7fffffff)%(SHARED_SIZE - 1));
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
+ SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
+ }
+#endif
+ if( res == 0 ){
+ pFile->lastErrno = osGetLastError();
+ /* No need to log a failure to lock */
+ }
+ OSTRACE(("READ-LOCK file=%p, result=%d\n", pFile->h, res));
+ return res;
+}
+
+/*
+** Undo a readlock
+*/
+static int winUnlockReadLock(winFile *pFile){
+ int res;
+ DWORD lastErrno;
+ OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
+ if( osIsNT() ){
+ res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ res = winUnlockFile(&pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
+ }
+#endif
+ if( res==0 && ((lastErrno = osGetLastError())!=ERROR_NOT_LOCKED) ){
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
+ "winUnlockReadLock", pFile->zPath);
+ }
+ OSTRACE(("READ-UNLOCK file=%p, result=%d\n", pFile->h, res));
+ return res;
+}
+
+/*
+** Lock the file with the lock specified by parameter locktype - one
+** of the following:
+**
+** (1) SHARED_LOCK
+** (2) RESERVED_LOCK
+** (3) PENDING_LOCK
+** (4) EXCLUSIVE_LOCK
+**
+** Sometimes when requesting one lock state, additional lock states
+** are inserted in between. The locking might fail on one of the later
+** transitions leaving the lock state different from what it started but
+** still short of its goal. The following chart shows the allowed
+** transitions and the inserted intermediate states:
+**
+** UNLOCKED -> SHARED
+** SHARED -> RESERVED
+** SHARED -> (PENDING) -> EXCLUSIVE
+** RESERVED -> (PENDING) -> EXCLUSIVE
+** PENDING -> EXCLUSIVE
+**
+** This routine will only increase a lock. The winUnlock() routine
+** erases all locks at once and returns us immediately to locking level 0.
+** It is not possible to lower the locking level one step at a time. You
+** must go straight to locking level 0.
+*/
+static int winLock(sqlite3_file *id, int locktype){
+ int rc = SQLITE_OK; /* Return code from subroutines */
+ int res = 1; /* Result of a Windows lock call */
+ int newLocktype; /* Set pFile->locktype to this value before exiting */
+ int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
+ winFile *pFile = (winFile*)id;
+ DWORD lastErrno = NO_ERROR;
+
+ assert( id!=0 );
+ OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
+ pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
+
+ /* If there is already a lock of this type or more restrictive on the
+ ** OsFile, do nothing. Don't use the end_lock: exit path, as
+ ** sqlite3OsEnterMutex() hasn't been called yet.
+ */
+ if( pFile->locktype>=locktype ){
+ OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+
+ /* Make sure the locking sequence is correct
+ */
+ assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
+ assert( locktype!=PENDING_LOCK );
+ assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
+
+ /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
+ ** a SHARED lock. If we are acquiring a SHARED lock, the acquisition of
+ ** the PENDING_LOCK byte is temporary.
+ */
+ newLocktype = pFile->locktype;
+ if( (pFile->locktype==NO_LOCK)
+ || ( (locktype==EXCLUSIVE_LOCK)
+ && (pFile->locktype==RESERVED_LOCK))
+ ){
+ int cnt = 3;
+ while( cnt-->0 && (res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS,
+ PENDING_BYTE, 0, 1, 0))==0 ){
+ /* Try 3 times to get the pending lock. This is needed to work
+ ** around problems caused by indexing and/or anti-virus software on
+ ** Windows systems.
+ ** If you are using this code as a model for alternative VFSes, do not
+ ** copy this retry logic. It is a hack intended for Windows only.
+ */
+ lastErrno = osGetLastError();
+ OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, result=%d\n",
+ pFile->h, cnt, res));
+ if( lastErrno==ERROR_INVALID_HANDLE ){
+ pFile->lastErrno = lastErrno;
+ rc = SQLITE_IOERR_LOCK;
+ OSTRACE(("LOCK-FAIL file=%p, count=%d, rc=%s\n",
+ pFile->h, cnt, sqlite3ErrName(rc)));
+ return rc;
+ }
+ if( cnt ) sqlite3_win32_sleep(1);
+ }
+ gotPendingLock = res;
+ if( !res ){
+ lastErrno = osGetLastError();
+ }
+ }
+
+ /* Acquire a shared lock
+ */
+ if( locktype==SHARED_LOCK && res ){
+ assert( pFile->locktype==NO_LOCK );
+ res = winGetReadLock(pFile);
+ if( res ){
+ newLocktype = SHARED_LOCK;
+ }else{
+ lastErrno = osGetLastError();
+ }
+ }
+
+ /* Acquire a RESERVED lock
+ */
+ if( locktype==RESERVED_LOCK && res ){
+ assert( pFile->locktype==SHARED_LOCK );
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, RESERVED_BYTE, 0, 1, 0);
+ if( res ){
+ newLocktype = RESERVED_LOCK;
+ }else{
+ lastErrno = osGetLastError();
+ }
+ }
+
+ /* Acquire a PENDING lock
+ */
+ if( locktype==EXCLUSIVE_LOCK && res ){
+ newLocktype = PENDING_LOCK;
+ gotPendingLock = 0;
+ }
+
+ /* Acquire an EXCLUSIVE lock
+ */
+ if( locktype==EXCLUSIVE_LOCK && res ){
+ assert( pFile->locktype>=SHARED_LOCK );
+ res = winUnlockReadLock(pFile);
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
+ SHARED_SIZE, 0);
+ if( res ){
+ newLocktype = EXCLUSIVE_LOCK;
+ }else{
+ lastErrno = osGetLastError();
+ winGetReadLock(pFile);
+ }
+ }
+
+ /* If we are holding a PENDING lock that ought to be released, then
+ ** release it now.
+ */
+ if( gotPendingLock && locktype==SHARED_LOCK ){
+ winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
+ }
+
+ /* Update the state of the lock has held in the file descriptor then
+ ** return the appropriate result code.
+ */
+ if( res ){
+ rc = SQLITE_OK;
+ }else{
+ pFile->lastErrno = lastErrno;
+ rc = SQLITE_BUSY;
+ OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
+ pFile->h, locktype, newLocktype));
+ }
+ pFile->locktype = (u8)newLocktype;
+ OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
+ pFile->h, pFile->locktype, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** This routine checks if there is a RESERVED lock held on the specified
+** file by this or any other process. If such a lock is held, return
+** non-zero, otherwise zero.
+*/
+static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
+ int res;
+ winFile *pFile = (winFile*)id;
+
+ SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+ OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));
+
+ assert( id!=0 );
+ if( pFile->locktype>=RESERVED_LOCK ){
+ res = 1;
+ OSTRACE(("TEST-WR-LOCK file=%p, result=%d (local)\n", pFile->h, res));
+ }else{
+ res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
+ if( res ){
+ winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
+ }
+ res = !res;
+ OSTRACE(("TEST-WR-LOCK file=%p, result=%d (remote)\n", pFile->h, res));
+ }
+ *pResOut = res;
+ OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
+ pFile->h, pResOut, *pResOut));
+ return SQLITE_OK;
+}
+
+/*
+** Lower the locking level on file descriptor id to locktype. locktype
+** must be either NO_LOCK or SHARED_LOCK.
+**
+** If the locking level of the file descriptor is already at or below
+** the requested locking level, this routine is a no-op.
+**
+** It is not possible for this routine to fail if the second argument
+** is NO_LOCK. If the second argument is SHARED_LOCK then this routine
+** might return SQLITE_IOERR;
+*/
+static int winUnlock(sqlite3_file *id, int locktype){
+ int type;
+ winFile *pFile = (winFile*)id;
+ int rc = SQLITE_OK;
+ assert( pFile!=0 );
+ assert( locktype<=SHARED_LOCK );
+ OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
+ pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
+ type = pFile->locktype;
+ if( type>=EXCLUSIVE_LOCK ){
+ winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
+ if( locktype==SHARED_LOCK && !winGetReadLock(pFile) ){
+ /* This should never happen. We should always be able to
+ ** reacquire the read lock */
+ rc = winLogError(SQLITE_IOERR_UNLOCK, osGetLastError(),
+ "winUnlock", pFile->zPath);
+ }
+ }
+ if( type>=RESERVED_LOCK ){
+ winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
+ }
+ if( locktype==NO_LOCK && type>=SHARED_LOCK ){
+ winUnlockReadLock(pFile);
+ }
+ if( type>=PENDING_LOCK ){
+ winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
+ }
+ pFile->locktype = (u8)locktype;
+ OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
+ pFile->h, pFile->locktype, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** If *pArg is inititially negative then this is a query. Set *pArg to
+** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
+**
+** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
+*/
+static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
+ if( *pArg<0 ){
+ *pArg = (pFile->ctrlFlags & mask)!=0;
+ }else if( (*pArg)==0 ){
+ pFile->ctrlFlags &= ~mask;
+ }else{
+ pFile->ctrlFlags |= mask;
+ }
+}
+
+/* Forward references to VFS helper methods used for temporary files */
+static int winGetTempname(sqlite3_vfs *, char **);
+static int winIsDir(const void *);
+static BOOL winIsDriveLetterAndColon(const char *);
+
+/*
+** Control and query of the open file handle.
+*/
+static int winFileControl(sqlite3_file *id, int op, void *pArg){
+ winFile *pFile = (winFile*)id;
+ OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
+ switch( op ){
+ case SQLITE_FCNTL_LOCKSTATE: {
+ *(int*)pArg = pFile->locktype;
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_LAST_ERRNO: {
+ *(int*)pArg = (int)pFile->lastErrno;
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_CHUNK_SIZE: {
+ pFile->szChunk = *(int *)pArg;
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_SIZE_HINT: {
+ if( pFile->szChunk>0 ){
+ sqlite3_int64 oldSz;
+ int rc = winFileSize(id, &oldSz);
+ if( rc==SQLITE_OK ){
+ sqlite3_int64 newSz = *(sqlite3_int64*)pArg;
+ if( newSz>oldSz ){
+ SimulateIOErrorBenign(1);
+ rc = winTruncate(id, newSz);
+ SimulateIOErrorBenign(0);
+ }
+ }
+ OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
+ return rc;
+ }
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_PERSIST_WAL: {
+ winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
+ winModeBit(pFile, WINFILE_PSOW, (int*)pArg);
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_VFSNAME: {
+ *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_WIN32_AV_RETRY: {
+ int *a = (int*)pArg;
+ if( a[0]>0 ){
+ winIoerrRetry = a[0];
+ }else{
+ a[0] = winIoerrRetry;
+ }
+ if( a[1]>0 ){
+ winIoerrRetryDelay = a[1];
+ }else{
+ a[1] = winIoerrRetryDelay;
+ }
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+ return SQLITE_OK;
+ }
+#ifdef SQLITE_TEST
+ case SQLITE_FCNTL_WIN32_SET_HANDLE: {
+ LPHANDLE phFile = (LPHANDLE)pArg;
+ HANDLE hOldFile = pFile->h;
+ pFile->h = *phFile;
+ *phFile = hOldFile;
+ OSTRACE(("FCNTL oldFile=%p, newFile=%p, rc=SQLITE_OK\n",
+ hOldFile, pFile->h));
+ return SQLITE_OK;
+ }
+#endif
+ case SQLITE_FCNTL_TEMPFILENAME: {
+ char *zTFile = 0;
+ int rc = winGetTempname(pFile->pVfs, &zTFile);
+ if( rc==SQLITE_OK ){
+ *(char**)pArg = zTFile;
+ }
+ OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
+ return rc;
+ }
+#if SQLITE_MAX_MMAP_SIZE>0
+ case SQLITE_FCNTL_MMAP_SIZE: {
+ i64 newLimit = *(i64*)pArg;
+ int rc = SQLITE_OK;
+ if( newLimit>sqlite3GlobalConfig.mxMmap ){
+ newLimit = sqlite3GlobalConfig.mxMmap;
+ }
+ *(i64*)pArg = pFile->mmapSizeMax;
+ if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
+ pFile->mmapSizeMax = newLimit;
+ if( pFile->mmapSize>0 ){
+ winUnmapfile(pFile);
+ rc = winMapfile(pFile, -1);
+ }
+ }
+ OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
+ return rc;
+ }
+#endif
+ }
+ OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
+ return SQLITE_NOTFOUND;
+}
+
+/*
+** Return the sector size in bytes of the underlying block device for
+** the specified file. This is almost always 512 bytes, but may be
+** larger for some devices.
+**
+** SQLite code assumes this function cannot fail. It also assumes that
+** if two files are created in the same file-system directory (i.e.
+** a database and its journal file) that the sector size will be the
+** same for both.
+*/
+static int winSectorSize(sqlite3_file *id){
+ (void)id;
+ return SQLITE_DEFAULT_SECTOR_SIZE;
+}
+
+/*
+** Return a vector of device characteristics.
+*/
+static int winDeviceCharacteristics(sqlite3_file *id){
+ winFile *p = (winFile*)id;
+ return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
+ ((p->ctrlFlags & WINFILE_PSOW)?SQLITE_IOCAP_POWERSAFE_OVERWRITE:0);
+}
+
+/*
+** Windows will only let you create file view mappings
+** on allocation size granularity boundaries.
+** During sqlite3_os_init() we do a GetSystemInfo()
+** to get the granularity size.
+*/
+static SYSTEM_INFO winSysInfo;
+
+#ifndef SQLITE_OMIT_WAL
+
+/*
+** Helper functions to obtain and relinquish the global mutex. The
+** global mutex is used to protect the winLockInfo objects used by
+** this file, all of which may be shared by multiple threads.
+**
+** Function winShmMutexHeld() is used to assert() that the global mutex
+** is held when required. This function is only used as part of assert()
+** statements. e.g.
+**
+** winShmEnterMutex()
+** assert( winShmMutexHeld() );
+** winShmLeaveMutex()
+*/
+static void winShmEnterMutex(void){
+ sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+static void winShmLeaveMutex(void){
+ sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+#ifndef NDEBUG
+static int winShmMutexHeld(void) {
+ return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+#endif
+
+/*
+** Object used to represent a single file opened and mmapped to provide
+** shared memory. When multiple threads all reference the same
+** log-summary, each thread has its own winFile object, but they all
+** point to a single instance of this object. In other words, each
+** log-summary is opened only once per process.
+**
+** winShmMutexHeld() must be true when creating or destroying
+** this object or while reading or writing the following fields:
+**
+** nRef
+** pNext
+**
+** The following fields are read-only after the object is created:
+**
+** fid
+** zFilename
+**
+** Either winShmNode.mutex must be held or winShmNode.nRef==0 and
+** winShmMutexHeld() is true when reading or writing any other field
+** in this structure.
+**
+*/
+struct winShmNode {
+ sqlite3_mutex *mutex; /* Mutex to access this object */
+ char *zFilename; /* Name of the file */
+ winFile hFile; /* File handle from winOpen */
+
+ int szRegion; /* Size of shared-memory regions */
+ int nRegion; /* Size of array apRegion */
+ struct ShmRegion {
+ HANDLE hMap; /* File handle from CreateFileMapping */
+ void *pMap;
+ } *aRegion;
+ DWORD lastErrno; /* The Windows errno from the last I/O error */
+
+ int nRef; /* Number of winShm objects pointing to this */
+ winShm *pFirst; /* All winShm objects pointing to this */
+ winShmNode *pNext; /* Next in list of all winShmNode objects */
+#ifdef SQLITE_DEBUG
+ u8 nextShmId; /* Next available winShm.id value */
+#endif
+};
+
+/*
+** A global array of all winShmNode objects.
+**
+** The winShmMutexHeld() must be true while reading or writing this list.
+*/
+static winShmNode *winShmNodeList = 0;
+
+/*
+** Structure used internally by this VFS to record the state of an
+** open shared memory connection.
+**
+** The following fields are initialized when this object is created and
+** are read-only thereafter:
+**
+** winShm.pShmNode
+** winShm.id
+**
+** All other fields are read/write. The winShm.pShmNode->mutex must be held
+** while accessing any read/write fields.
+*/
+struct winShm {
+ winShmNode *pShmNode; /* The underlying winShmNode object */
+ winShm *pNext; /* Next winShm with the same winShmNode */
+ u8 hasMutex; /* True if holding the winShmNode mutex */
+ u16 sharedMask; /* Mask of shared locks held */
+ u16 exclMask; /* Mask of exclusive locks held */
+#ifdef SQLITE_DEBUG
+ u8 id; /* Id of this connection with its winShmNode */
+#endif
+};
+
+/*
+** Constants used for locking
+*/
+#define WIN_SHM_BASE ((22+SQLITE_SHM_NLOCK)*4) /* first lock byte */
+#define WIN_SHM_DMS (WIN_SHM_BASE+SQLITE_SHM_NLOCK) /* deadman switch */
+
+/*
+** Apply advisory locks for all n bytes beginning at ofst.
+*/
+#define _SHM_UNLCK 1
+#define _SHM_RDLCK 2
+#define _SHM_WRLCK 3
+static int winShmSystemLock(
+ winShmNode *pFile, /* Apply locks to this open shared-memory segment */
+ int lockType, /* _SHM_UNLCK, _SHM_RDLCK, or _SHM_WRLCK */
+ int ofst, /* Offset to first byte to be locked/unlocked */
+ int nByte /* Number of bytes to lock or unlock */
+){
+ int rc = 0; /* Result code form Lock/UnlockFileEx() */
+
+ /* Access to the winShmNode object is serialized by the caller */
+ assert( sqlite3_mutex_held(pFile->mutex) || pFile->nRef==0 );
+
+ OSTRACE(("SHM-LOCK file=%p, lock=%d, offset=%d, size=%d\n",
+ pFile->hFile.h, lockType, ofst, nByte));
+
+ /* Release/Acquire the system-level lock */
+ if( lockType==_SHM_UNLCK ){
+ rc = winUnlockFile(&pFile->hFile.h, ofst, 0, nByte, 0);
+ }else{
+ /* Initialize the locking parameters */
+ DWORD dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
+ if( lockType == _SHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
+ rc = winLockFile(&pFile->hFile.h, dwFlags, ofst, 0, nByte, 0);
+ }
+
+ if( rc!= 0 ){
+ rc = SQLITE_OK;
+ }else{
+ pFile->lastErrno = osGetLastError();
+ rc = SQLITE_BUSY;
+ }
+
+ OSTRACE(("SHM-LOCK file=%p, func=%s, errno=%lu, rc=%s\n",
+ pFile->hFile.h, (lockType == _SHM_UNLCK) ? "winUnlockFile" :
+ "winLockFile", pFile->lastErrno, sqlite3ErrName(rc)));
+
+ return rc;
+}
+
+/* Forward references to VFS methods */
+static int winOpen(sqlite3_vfs*,const char*,sqlite3_file*,int,int*);
+static int winDelete(sqlite3_vfs *,const char*,int);
+
+/*
+** Purge the winShmNodeList list of all entries with winShmNode.nRef==0.
+**
+** This is not a VFS shared-memory method; it is a utility function called
+** by VFS shared-memory methods.
+*/
+static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
+ winShmNode **pp;
+ winShmNode *p;
+ assert( winShmMutexHeld() );
+ OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
+ osGetCurrentProcessId(), deleteFlag));
+ pp = &winShmNodeList;
+ while( (p = *pp)!=0 ){
+ if( p->nRef==0 ){
+ int i;
+ if( p->mutex ){ sqlite3_mutex_free(p->mutex); }
+ for(i=0; inRegion; i++){
+ BOOL bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
+ OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
+ osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
+ UNUSED_VARIABLE_VALUE(bRc);
+ bRc = osCloseHandle(p->aRegion[i].hMap);
+ OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
+ osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
+ UNUSED_VARIABLE_VALUE(bRc);
+ }
+ if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
+ SimulateIOErrorBenign(1);
+ winClose((sqlite3_file *)&p->hFile);
+ SimulateIOErrorBenign(0);
+ }
+ if( deleteFlag ){
+ SimulateIOErrorBenign(1);
+ sqlite3BeginBenignMalloc();
+ winDelete(pVfs, p->zFilename, 0);
+ sqlite3EndBenignMalloc();
+ SimulateIOErrorBenign(0);
+ }
+ *pp = p->pNext;
+ sqlite3_free(p->aRegion);
+ sqlite3_free(p);
+ }else{
+ pp = &p->pNext;
+ }
+ }
+}
+
+/*
+** Open the shared-memory area associated with database file pDbFd.
+**
+** When opening a new shared-memory file, if no other instances of that
+** file are currently open, in this process or in other processes, then
+** the file must be truncated to zero length or have its header cleared.
+*/
+static int winOpenSharedMemory(winFile *pDbFd){
+ struct winShm *p; /* The connection to be opened */
+ struct winShmNode *pShmNode = 0; /* The underlying mmapped file */
+ int rc; /* Result code */
+ struct winShmNode *pNew; /* Newly allocated winShmNode */
+ int nName; /* Size of zName in bytes */
+
+ assert( pDbFd->pShm==0 ); /* Not previously opened */
+
+ /* Allocate space for the new sqlite3_shm object. Also speculatively
+ ** allocate space for a new winShmNode and filename.
+ */
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p==0 ) return SQLITE_IOERR_NOMEM;
+ nName = sqlite3Strlen30(pDbFd->zPath);
+ pNew = sqlite3MallocZero( sizeof(*pShmNode) + nName + 17 );
+ if( pNew==0 ){
+ sqlite3_free(p);
+ return SQLITE_IOERR_NOMEM;
+ }
+ pNew->zFilename = (char*)&pNew[1];
+ sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
+ sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename);
+
+ /* Look to see if there is an existing winShmNode that can be used.
+ ** If no matching winShmNode currently exists, create a new one.
+ */
+ winShmEnterMutex();
+ for(pShmNode = winShmNodeList; pShmNode; pShmNode=pShmNode->pNext){
+ /* TBD need to come up with better match here. Perhaps
+ ** use FILE_ID_BOTH_DIR_INFO Structure.
+ */
+ if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break;
+ }
+ if( pShmNode ){
+ sqlite3_free(pNew);
+ }else{
+ pShmNode = pNew;
+ pNew = 0;
+ ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE;
+ pShmNode->pNext = winShmNodeList;
+ winShmNodeList = pShmNode;
+
+ pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
+ if( pShmNode->mutex==0 ){
+ rc = SQLITE_IOERR_NOMEM;
+ goto shm_open_err;
+ }
+
+ rc = winOpen(pDbFd->pVfs,
+ pShmNode->zFilename, /* Name of the file (UTF-8) */
+ (sqlite3_file*)&pShmNode->hFile, /* File handle here */
+ SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE,
+ 0);
+ if( SQLITE_OK!=rc ){
+ goto shm_open_err;
+ }
+
+ /* Check to see if another process is holding the dead-man switch.
+ ** If not, truncate the file to zero length.
+ */
+ if( winShmSystemLock(pShmNode, _SHM_WRLCK, WIN_SHM_DMS, 1)==SQLITE_OK ){
+ rc = winTruncate((sqlite3_file *)&pShmNode->hFile, 0);
+ if( rc!=SQLITE_OK ){
+ rc = winLogError(SQLITE_IOERR_SHMOPEN, osGetLastError(),
+ "winOpenShm", pDbFd->zPath);
+ }
+ }
+ if( rc==SQLITE_OK ){
+ winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
+ rc = winShmSystemLock(pShmNode, _SHM_RDLCK, WIN_SHM_DMS, 1);
+ }
+ if( rc ) goto shm_open_err;
+ }
+
+ /* Make the new connection a child of the winShmNode */
+ p->pShmNode = pShmNode;
+#ifdef SQLITE_DEBUG
+ p->id = pShmNode->nextShmId++;
+#endif
+ pShmNode->nRef++;
+ pDbFd->pShm = p;
+ winShmLeaveMutex();
+
+ /* The reference count on pShmNode has already been incremented under
+ ** the cover of the winShmEnterMutex() mutex and the pointer from the
+ ** new (struct winShm) object to the pShmNode has been set. All that is
+ ** left to do is to link the new object into the linked list starting
+ ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex
+ ** mutex.
+ */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ p->pNext = pShmNode->pFirst;
+ pShmNode->pFirst = p;
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return SQLITE_OK;
+
+ /* Jump here on any error */
+shm_open_err:
+ winShmSystemLock(pShmNode, _SHM_UNLCK, WIN_SHM_DMS, 1);
+ winShmPurge(pDbFd->pVfs, 0); /* This call frees pShmNode if required */
+ sqlite3_free(p);
+ sqlite3_free(pNew);
+ winShmLeaveMutex();
+ return rc;
+}
+
+/*
+** Close a connection to shared-memory. Delete the underlying
+** storage if deleteFlag is true.
+*/
+static int winShmUnmap(
+ sqlite3_file *fd, /* Database holding shared memory */
+ int deleteFlag /* Delete after closing if true */
+){
+ winFile *pDbFd; /* Database holding shared-memory */
+ winShm *p; /* The connection to be closed */
+ winShmNode *pShmNode; /* The underlying shared-memory file */
+ winShm **pp; /* For looping over sibling connections */
+
+ pDbFd = (winFile*)fd;
+ p = pDbFd->pShm;
+ if( p==0 ) return SQLITE_OK;
+ pShmNode = p->pShmNode;
+
+ /* Remove connection p from the set of connections associated
+ ** with pShmNode */
+ sqlite3_mutex_enter(pShmNode->mutex);
+ for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
+ *pp = p->pNext;
+
+ /* Free the connection p */
+ sqlite3_free(p);
+ pDbFd->pShm = 0;
+ sqlite3_mutex_leave(pShmNode->mutex);
+
+ /* If pShmNode->nRef has reached 0, then close the underlying
+ ** shared-memory file, too */
+ winShmEnterMutex();
+ assert( pShmNode->nRef>0 );
+ pShmNode->nRef--;
+ if( pShmNode->nRef==0 ){
+ winShmPurge(pDbFd->pVfs, deleteFlag);
+ }
+ winShmLeaveMutex();
+
+ return SQLITE_OK;
+}
+
+/*
+** Change the lock state for a shared-memory segment.
+*/
+static int winShmLock(
+ sqlite3_file *fd, /* Database file holding the shared memory */
+ int ofst, /* First lock to acquire or release */
+ int n, /* Number of locks to acquire or release */
+ int flags /* What to do with the lock */
+){
+ winFile *pDbFd = (winFile*)fd; /* Connection holding shared memory */
+ winShm *p = pDbFd->pShm; /* The shared memory being locked */
+ winShm *pX; /* For looping over all siblings */
+ winShmNode *pShmNode = p->pShmNode;
+ int rc = SQLITE_OK; /* Result code */
+ u16 mask; /* Mask of locks to take or release */
+
+ assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
+ assert( n>=1 );
+ assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
+ assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
+
+ mask = (u16)((1U<<(ofst+n)) - (1U<1 || mask==(1<mutex);
+ if( flags & SQLITE_SHM_UNLOCK ){
+ u16 allMask = 0; /* Mask of locks held by siblings */
+
+ /* See if any siblings hold this same lock */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( pX==p ) continue;
+ assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
+ allMask |= pX->sharedMask;
+ }
+
+ /* Unlock the system-level locks */
+ if( (mask & allMask)==0 ){
+ rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+
+ /* Undo the local locks */
+ if( rc==SQLITE_OK ){
+ p->exclMask &= ~mask;
+ p->sharedMask &= ~mask;
+ }
+ }else if( flags & SQLITE_SHM_SHARED ){
+ u16 allShared = 0; /* Union of locks held by connections other than "p" */
+
+ /* Find out which shared locks are already held by sibling connections.
+ ** If any sibling already holds an exclusive lock, go ahead and return
+ ** SQLITE_BUSY.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ allShared |= pX->sharedMask;
+ }
+
+ /* Get shared locks at the system level, if necessary */
+ if( rc==SQLITE_OK ){
+ if( (allShared & mask)==0 ){
+ rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+ }
+
+ /* Get the local shared locks */
+ if( rc==SQLITE_OK ){
+ p->sharedMask |= mask;
+ }
+ }else{
+ /* Make sure no sibling connections hold locks that will block this
+ ** lock. If any do, return SQLITE_BUSY right away.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ }
+
+ /* Get the exclusive locks at the system level. Then if successful
+ ** also mark the local connection as being locked.
+ */
+ if( rc==SQLITE_OK ){
+ rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
+ if( rc==SQLITE_OK ){
+ assert( (p->sharedMask & mask)==0 );
+ p->exclMask |= mask;
+ }
+ }
+ }
+ sqlite3_mutex_leave(pShmNode->mutex);
+ OSTRACE(("SHM-LOCK pid=%lu, id=%d, sharedMask=%03x, exclMask=%03x, rc=%s\n",
+ osGetCurrentProcessId(), p->id, p->sharedMask, p->exclMask,
+ sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** Implement a memory barrier or memory fence on shared memory.
+**
+** All loads and stores begun before the barrier must complete before
+** any load or store begun after the barrier.
+*/
+static void winShmBarrier(
+ sqlite3_file *fd /* Database holding the shared memory */
+){
+ UNUSED_PARAMETER(fd);
+ /* MemoryBarrier(); // does not work -- do not know why not */
+ winShmEnterMutex();
+ winShmLeaveMutex();
+}
+
+/*
+** This function is called to obtain a pointer to region iRegion of the
+** shared-memory associated with the database file fd. Shared-memory regions
+** are numbered starting from zero. Each shared-memory region is szRegion
+** bytes in size.
+**
+** If an error occurs, an error code is returned and *pp is set to NULL.
+**
+** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
+** region has not been allocated (by any client, including one running in a
+** separate process), then *pp is set to NULL and SQLITE_OK returned. If
+** isWrite is non-zero and the requested shared-memory region has not yet
+** been allocated, it is allocated by this function.
+**
+** If the shared-memory region has already been allocated or is allocated by
+** this call as described above, then it is mapped into this processes
+** address space (if it is not already), *pp is set to point to the mapped
+** memory and SQLITE_OK returned.
+*/
+static int winShmMap(
+ sqlite3_file *fd, /* Handle open on database file */
+ int iRegion, /* Region to retrieve */
+ int szRegion, /* Size of regions */
+ int isWrite, /* True to extend file if necessary */
+ void volatile **pp /* OUT: Mapped memory */
+){
+ winFile *pDbFd = (winFile*)fd;
+ winShm *p = pDbFd->pShm;
+ winShmNode *pShmNode;
+ int rc = SQLITE_OK;
+
+ if( !p ){
+ rc = winOpenSharedMemory(pDbFd);
+ if( rc!=SQLITE_OK ) return rc;
+ p = pDbFd->pShm;
+ }
+ pShmNode = p->pShmNode;
+
+ sqlite3_mutex_enter(pShmNode->mutex);
+ assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+
+ if( pShmNode->nRegion<=iRegion ){
+ struct ShmRegion *apNew; /* New aRegion[] array */
+ int nByte = (iRegion+1)*szRegion; /* Minimum required file size */
+ sqlite3_int64 sz; /* Current size of wal-index file */
+
+ pShmNode->szRegion = szRegion;
+
+ /* The requested region is not mapped into this processes address space.
+ ** Check to see if it has been allocated (i.e. if the wal-index file is
+ ** large enough to contain the requested region).
+ */
+ rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
+ if( rc!=SQLITE_OK ){
+ rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
+ "winShmMap1", pDbFd->zPath);
+ goto shmpage_out;
+ }
+
+ if( szhFile, nByte);
+ if( rc!=SQLITE_OK ){
+ rc = winLogError(SQLITE_IOERR_SHMSIZE, osGetLastError(),
+ "winShmMap2", pDbFd->zPath);
+ goto shmpage_out;
+ }
+ }
+
+ /* Map the requested memory region into this processes address space. */
+ apNew = (struct ShmRegion *)sqlite3_realloc(
+ pShmNode->aRegion, (iRegion+1)*sizeof(apNew[0])
+ );
+ if( !apNew ){
+ rc = SQLITE_IOERR_NOMEM;
+ goto shmpage_out;
+ }
+ pShmNode->aRegion = apNew;
+
+ while( pShmNode->nRegion<=iRegion ){
+ HANDLE hMap = NULL; /* file-mapping handle */
+ void *pMap = 0; /* Mapped memory region */
+
+#if SQLITE_OS_WINRT
+ hMap = osCreateFileMappingFromApp(pShmNode->hFile.h,
+ NULL, PAGE_READWRITE, nByte, NULL
+ );
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+ hMap = osCreateFileMappingW(pShmNode->hFile.h,
+ NULL, PAGE_READWRITE, 0, nByte, NULL
+ );
+#elif defined(SQLITE_WIN32_HAS_ANSI)
+ hMap = osCreateFileMappingA(pShmNode->hFile.h,
+ NULL, PAGE_READWRITE, 0, nByte, NULL
+ );
+#endif
+ OSTRACE(("SHM-MAP-CREATE pid=%lu, region=%d, size=%d, rc=%s\n",
+ osGetCurrentProcessId(), pShmNode->nRegion, nByte,
+ hMap ? "ok" : "failed"));
+ if( hMap ){
+ int iOffset = pShmNode->nRegion*szRegion;
+ int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
+#if SQLITE_OS_WINRT
+ pMap = osMapViewOfFileFromApp(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
+ iOffset - iOffsetShift, szRegion + iOffsetShift
+ );
+#else
+ pMap = osMapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
+ 0, iOffset - iOffsetShift, szRegion + iOffsetShift
+ );
+#endif
+ OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
+ osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
+ szRegion, pMap ? "ok" : "failed"));
+ }
+ if( !pMap ){
+ pShmNode->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_SHMMAP, pShmNode->lastErrno,
+ "winShmMap3", pDbFd->zPath);
+ if( hMap ) osCloseHandle(hMap);
+ goto shmpage_out;
+ }
+
+ pShmNode->aRegion[pShmNode->nRegion].pMap = pMap;
+ pShmNode->aRegion[pShmNode->nRegion].hMap = hMap;
+ pShmNode->nRegion++;
+ }
+ }
+
+shmpage_out:
+ if( pShmNode->nRegion>iRegion ){
+ int iOffset = iRegion*szRegion;
+ int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
+ char *p = (char *)pShmNode->aRegion[iRegion].pMap;
+ *pp = (void *)&p[iOffsetShift];
+ }else{
+ *pp = 0;
+ }
+ sqlite3_mutex_leave(pShmNode->mutex);
+ return rc;
+}
+
+#else
+# define winShmMap 0
+# define winShmLock 0
+# define winShmBarrier 0
+# define winShmUnmap 0
+#endif /* #ifndef SQLITE_OMIT_WAL */
+
+/*
+** Cleans up the mapped region of the specified file, if any.
+*/
+#if SQLITE_MAX_MMAP_SIZE>0
+static int winUnmapfile(winFile *pFile){
+ assert( pFile!=0 );
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, pMapRegion=%p, "
+ "mmapSize=%lld, mmapSizeActual=%lld, mmapSizeMax=%lld\n",
+ osGetCurrentProcessId(), pFile, pFile->hMap, pFile->pMapRegion,
+ pFile->mmapSize, pFile->mmapSizeActual, pFile->mmapSizeMax));
+ if( pFile->pMapRegion ){
+ if( !osUnmapViewOfFile(pFile->pMapRegion) ){
+ pFile->lastErrno = osGetLastError();
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
+ "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
+ pFile->pMapRegion));
+ return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
+ "winUnmapfile1", pFile->zPath);
+ }
+ pFile->pMapRegion = 0;
+ pFile->mmapSize = 0;
+ pFile->mmapSizeActual = 0;
+ }
+ if( pFile->hMap!=NULL ){
+ if( !osCloseHandle(pFile->hMap) ){
+ pFile->lastErrno = osGetLastError();
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
+ osGetCurrentProcessId(), pFile, pFile->hMap));
+ return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
+ "winUnmapfile2", pFile->zPath);
+ }
+ pFile->hMap = NULL;
+ }
+ OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFile));
+ return SQLITE_OK;
+}
+
+/*
+** Memory map or remap the file opened by file-descriptor pFd (if the file
+** is already mapped, the existing mapping is replaced by the new). Or, if
+** there already exists a mapping for this file, and there are still
+** outstanding xFetch() references to it, this function is a no-op.
+**
+** If parameter nByte is non-negative, then it is the requested size of
+** the mapping to create. Otherwise, if nByte is less than zero, then the
+** requested size is the size of the file on disk. The actual size of the
+** created mapping is either the requested size or the value configured
+** using SQLITE_FCNTL_MMAP_SIZE, whichever is smaller.
+**
+** SQLITE_OK is returned if no error occurs (even if the mapping is not
+** recreated as a result of outstanding references) or an SQLite error
+** code otherwise.
+*/
+static int winMapfile(winFile *pFd, sqlite3_int64 nByte){
+ sqlite3_int64 nMap = nByte;
+ int rc;
+
+ assert( nMap>=0 || pFd->nFetchOut==0 );
+ OSTRACE(("MAP-FILE pid=%lu, pFile=%p, size=%lld\n",
+ osGetCurrentProcessId(), pFd, nByte));
+
+ if( pFd->nFetchOut>0 ) return SQLITE_OK;
+
+ if( nMap<0 ){
+ rc = winFileSize((sqlite3_file*)pFd, &nMap);
+ if( rc ){
+ OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_IOERR_FSTAT\n",
+ osGetCurrentProcessId(), pFd));
+ return SQLITE_IOERR_FSTAT;
+ }
+ }
+ if( nMap>pFd->mmapSizeMax ){
+ nMap = pFd->mmapSizeMax;
+ }
+ nMap &= ~(sqlite3_int64)(winSysInfo.dwPageSize - 1);
+
+ if( nMap==0 && pFd->mmapSize>0 ){
+ winUnmapfile(pFd);
+ }
+ if( nMap!=pFd->mmapSize ){
+ void *pNew = 0;
+ DWORD protect = PAGE_READONLY;
+ DWORD flags = FILE_MAP_READ;
+
+ winUnmapfile(pFd);
+ if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
+ protect = PAGE_READWRITE;
+ flags |= FILE_MAP_WRITE;
+ }
+#if SQLITE_OS_WINRT
+ pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+ pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
+ (DWORD)((nMap>>32) & 0xffffffff),
+ (DWORD)(nMap & 0xffffffff), NULL);
+#elif defined(SQLITE_WIN32_HAS_ANSI)
+ pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
+ (DWORD)((nMap>>32) & 0xffffffff),
+ (DWORD)(nMap & 0xffffffff), NULL);
+#endif
+ if( pFd->hMap==NULL ){
+ pFd->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
+ "winMapfile1", pFd->zPath);
+ /* Log the error, but continue normal operation using xRead/xWrite */
+ OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
+ return SQLITE_OK;
+ }
+ assert( (nMap % winSysInfo.dwPageSize)==0 );
+ assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
+#if SQLITE_OS_WINRT
+ pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
+#else
+ pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
+#endif
+ if( pNew==NULL ){
+ osCloseHandle(pFd->hMap);
+ pFd->hMap = NULL;
+ pFd->lastErrno = osGetLastError();
+ rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
+ "winMapfile2", pFd->zPath);
+ /* Log the error, but continue normal operation using xRead/xWrite */
+ OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
+ return SQLITE_OK;
+ }
+ pFd->pMapRegion = pNew;
+ pFd->mmapSize = nMap;
+ pFd->mmapSizeActual = nMap;
+ }
+
+ OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), pFd));
+ return SQLITE_OK;
+}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+
+/*
+** If possible, return a pointer to a mapping of file fd starting at offset
+** iOff. The mapping must be valid for at least nAmt bytes.
+**
+** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
+** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
+** Finally, if an error does occur, return an SQLite error code. The final
+** value of *pp is undefined in this case.
+**
+** If this function does return a pointer, the caller must eventually
+** release the reference by calling winUnfetch().
+*/
+static int winFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
+#if SQLITE_MAX_MMAP_SIZE>0
+ winFile *pFd = (winFile*)fd; /* The underlying database file */
+#endif
+ *pp = 0;
+
+ OSTRACE(("FETCH pid=%lu, pFile=%p, offset=%lld, amount=%d, pp=%p\n",
+ osGetCurrentProcessId(), fd, iOff, nAmt, pp));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+ if( pFd->mmapSizeMax>0 ){
+ if( pFd->pMapRegion==0 ){
+ int rc = winMapfile(pFd, -1);
+ if( rc!=SQLITE_OK ){
+ OSTRACE(("FETCH pid=%lu, pFile=%p, rc=%s\n",
+ osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
+ return rc;
+ }
+ }
+ if( pFd->mmapSize >= iOff+nAmt ){
+ *pp = &((u8 *)pFd->pMapRegion)[iOff];
+ pFd->nFetchOut++;
+ }
+ }
+#endif
+
+ OSTRACE(("FETCH pid=%lu, pFile=%p, pp=%p, *pp=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), fd, pp, *pp));
+ return SQLITE_OK;
+}
+
+/*
+** If the third argument is non-NULL, then this function releases a
+** reference obtained by an earlier call to winFetch(). The second
+** argument passed to this function must be the same as the corresponding
+** argument that was passed to the winFetch() invocation.
+**
+** Or, if the third argument is NULL, then this function is being called
+** to inform the VFS layer that, according to POSIX, any existing mapping
+** may now be invalid and should be unmapped.
+*/
+static int winUnfetch(sqlite3_file *fd, i64 iOff, void *p){
+#if SQLITE_MAX_MMAP_SIZE>0
+ winFile *pFd = (winFile*)fd; /* The underlying database file */
+
+ /* If p==0 (unmap the entire file) then there must be no outstanding
+ ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
+ ** then there must be at least one outstanding. */
+ assert( (p==0)==(pFd->nFetchOut==0) );
+
+ /* If p!=0, it must match the iOff value. */
+ assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
+
+ OSTRACE(("UNFETCH pid=%lu, pFile=%p, offset=%lld, p=%p\n",
+ osGetCurrentProcessId(), pFd, iOff, p));
+
+ if( p ){
+ pFd->nFetchOut--;
+ }else{
+ /* FIXME: If Windows truly always prevents truncating or deleting a
+ ** file while a mapping is held, then the following winUnmapfile() call
+ ** is unnecessary can can be omitted - potentially improving
+ ** performance. */
+ winUnmapfile(pFd);
+ }
+
+ assert( pFd->nFetchOut>=0 );
+#endif
+
+ OSTRACE(("UNFETCH pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+ osGetCurrentProcessId(), fd));
+ return SQLITE_OK;
+}
+
+/*
+** Here ends the implementation of all sqlite3_file methods.
+**
+********************** End sqlite3_file Methods *******************************
+******************************************************************************/
+
+/*
+** This vector defines all the methods that can operate on an
+** sqlite3_file for win32.
+*/
+static const sqlite3_io_methods winIoMethod = {
+ 3, /* iVersion */
+ winClose, /* xClose */
+ winRead, /* xRead */
+ winWrite, /* xWrite */
+ winTruncate, /* xTruncate */
+ winSync, /* xSync */
+ winFileSize, /* xFileSize */
+ winLock, /* xLock */
+ winUnlock, /* xUnlock */
+ winCheckReservedLock, /* xCheckReservedLock */
+ winFileControl, /* xFileControl */
+ winSectorSize, /* xSectorSize */
+ winDeviceCharacteristics, /* xDeviceCharacteristics */
+ winShmMap, /* xShmMap */
+ winShmLock, /* xShmLock */
+ winShmBarrier, /* xShmBarrier */
+ winShmUnmap, /* xShmUnmap */
+ winFetch, /* xFetch */
+ winUnfetch /* xUnfetch */
+};
+
+/****************************************************************************
+**************************** sqlite3_vfs methods ****************************
+**
+** This division contains the implementation of methods on the
+** sqlite3_vfs object.
+*/
+
+#if defined(__CYGWIN__)
+/*
+** Convert a filename from whatever the underlying operating system
+** supports for filenames into UTF-8. Space to hold the result is
+** obtained from malloc and must be freed by the calling function.
+*/
+static char *winConvertToUtf8Filename(const void *zFilename){
+ char *zConverted = 0;
+ if( osIsNT() ){
+ zConverted = winUnicodeToUtf8(zFilename);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ zConverted = sqlite3_win32_mbcs_to_utf8(zFilename);
+ }
+#endif
+ /* caller will handle out of memory */
+ return zConverted;
+}
+#endif
+
+/*
+** Convert a UTF-8 filename into whatever form the underlying
+** operating system wants filenames in. Space to hold the result
+** is obtained from malloc and must be freed by the calling
+** function.
+*/
+static void *winConvertFromUtf8Filename(const char *zFilename){
+ void *zConverted = 0;
+ if( osIsNT() ){
+ zConverted = winUtf8ToUnicode(zFilename);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ zConverted = sqlite3_win32_utf8_to_mbcs(zFilename);
+ }
+#endif
+ /* caller will handle out of memory */
+ return zConverted;
+}
+
+/*
+** This function returns non-zero if the specified UTF-8 string buffer
+** ends with a directory separator character or one was successfully
+** added to it.
+*/
+static int winMakeEndInDirSep(int nBuf, char *zBuf){
+ if( zBuf ){
+ int nLen = sqlite3Strlen30(zBuf);
+ if( nLen>0 ){
+ if( winIsDirSep(zBuf[nLen-1]) ){
+ return 1;
+ }else if( nLen+1mxPathname; nBuf = nMax + 2;
+ zBuf = sqlite3MallocZero( nBuf );
+ if( !zBuf ){
+ OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
+ return SQLITE_IOERR_NOMEM;
+ }
+
+ /* Figure out the effective temporary directory. First, check if one
+ ** has been explicitly set by the application; otherwise, use the one
+ ** configured by the operating system.
+ */
+ nDir = nMax - (nPre + 15);
+ assert( nDir>0 );
+ if( sqlite3_temp_directory ){
+ int nDirLen = sqlite3Strlen30(sqlite3_temp_directory);
+ if( nDirLen>0 ){
+ if( !winIsDirSep(sqlite3_temp_directory[nDirLen-1]) ){
+ nDirLen++;
+ }
+ if( nDirLen>nDir ){
+ sqlite3_free(zBuf);
+ OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
+ return winLogError(SQLITE_ERROR, 0, "winGetTempname1", 0);
+ }
+ sqlite3_snprintf(nMax, zBuf, "%s", sqlite3_temp_directory);
+ }
+ }
+#if defined(__CYGWIN__)
+ else{
+ static const char *azDirs[] = {
+ 0, /* getenv("SQLITE_TMPDIR") */
+ 0, /* getenv("TMPDIR") */
+ 0, /* getenv("TMP") */
+ 0, /* getenv("TEMP") */
+ 0, /* getenv("USERPROFILE") */
+ "/var/tmp",
+ "/usr/tmp",
+ "/tmp",
+ ".",
+ 0 /* List terminator */
+ };
+ unsigned int i;
+ const char *zDir = 0;
+
+ if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
+ if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");
+ if( !azDirs[2] ) azDirs[2] = getenv("TMP");
+ if( !azDirs[3] ) azDirs[3] = getenv("TEMP");
+ if( !azDirs[4] ) azDirs[4] = getenv("USERPROFILE");
+ for(i=0; i/etilqs_XXXXXXXXXXXXXXX\0\0"
+ **
+ ** If not, return SQLITE_ERROR. The number 17 is used here in order to
+ ** account for the space used by the 15 character random suffix and the
+ ** two trailing NUL characters. The final directory separator character
+ ** has already added if it was not already present.
+ */
+ nLen = sqlite3Strlen30(zBuf);
+ if( (nLen + nPre + 17) > nBuf ){
+ sqlite3_free(zBuf);
+ OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
+ return winLogError(SQLITE_ERROR, 0, "winGetTempname5", 0);
+ }
+
+ sqlite3_snprintf(nBuf-16-nLen, zBuf+nLen, SQLITE_TEMP_FILE_PREFIX);
+
+ j = sqlite3Strlen30(zBuf);
+ sqlite3_randomness(15, &zBuf[j]);
+ for(i=0; i<15; i++, j++){
+ zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+ }
+ zBuf[j] = 0;
+ zBuf[j+1] = 0;
+ *pzBuf = zBuf;
+
+ OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
+ return SQLITE_OK;
+}
+
+/*
+** Return TRUE if the named file is really a directory. Return false if
+** it is something other than a directory, or if there is any kind of memory
+** allocation failure.
+*/
+static int winIsDir(const void *zConverted){
+ DWORD attr;
+ int rc = 0;
+ DWORD lastErrno;
+
+ if( osIsNT() ){
+ int cnt = 0;
+ WIN32_FILE_ATTRIBUTE_DATA sAttrData;
+ memset(&sAttrData, 0, sizeof(sAttrData));
+ while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
+ GetFileExInfoStandard,
+ &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
+ if( !rc ){
+ return 0; /* Invalid name? */
+ }
+ attr = sAttrData.dwFileAttributes;
+#if SQLITE_OS_WINCE==0
+ }else{
+ attr = osGetFileAttributesA((char*)zConverted);
+#endif
+ }
+ return (attr!=INVALID_FILE_ATTRIBUTES) && (attr&FILE_ATTRIBUTE_DIRECTORY);
+}
+
+/*
+** Open a file.
+*/
+static int winOpen(
+ sqlite3_vfs *pVfs, /* Used to get maximum path name length */
+ const char *zName, /* Name of the file (UTF-8) */
+ sqlite3_file *id, /* Write the SQLite file handle here */
+ int flags, /* Open mode flags */
+ int *pOutFlags /* Status return flags */
+){
+ HANDLE h;
+ DWORD lastErrno = 0;
+ DWORD dwDesiredAccess;
+ DWORD dwShareMode;
+ DWORD dwCreationDisposition;
+ DWORD dwFlagsAndAttributes = 0;
+#if SQLITE_OS_WINCE
+ int isTemp = 0;
+#endif
+ winFile *pFile = (winFile*)id;
+ void *zConverted; /* Filename in OS encoding */
+ const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
+ int cnt = 0;
+
+ /* If argument zPath is a NULL pointer, this function is required to open
+ ** a temporary file. Use this buffer to store the file name in.
+ */
+ char *zTmpname = 0; /* For temporary filename, if necessary. */
+
+ int rc = SQLITE_OK; /* Function Return Code */
+#if !defined(NDEBUG) || SQLITE_OS_WINCE
+ int eType = flags&0xFFFFFF00; /* Type of file to open */
+#endif
+
+ int isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE);
+ int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE);
+ int isCreate = (flags & SQLITE_OPEN_CREATE);
+ int isReadonly = (flags & SQLITE_OPEN_READONLY);
+ int isReadWrite = (flags & SQLITE_OPEN_READWRITE);
+
+#ifndef NDEBUG
+ int isOpenJournal = (isCreate && (
+ eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_MAIN_JOURNAL
+ || eType==SQLITE_OPEN_WAL
+ ));
+#endif
+
+ OSTRACE(("OPEN name=%s, pFile=%p, flags=%x, pOutFlags=%p\n",
+ zUtf8Name, id, flags, pOutFlags));
+
+ /* Check the following statements are true:
+ **
+ ** (a) Exactly one of the READWRITE and READONLY flags must be set, and
+ ** (b) if CREATE is set, then READWRITE must also be set, and
+ ** (c) if EXCLUSIVE is set, then CREATE must also be set.
+ ** (d) if DELETEONCLOSE is set, then CREATE must also be set.
+ */
+ assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
+ assert(isCreate==0 || isReadWrite);
+ assert(isExclusive==0 || isCreate);
+ assert(isDelete==0 || isCreate);
+
+ /* The main DB, main journal, WAL file and master journal are never
+ ** automatically deleted. Nor are they ever temporary files. */
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+ assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
+
+ /* Assert that the upper layer has set one of the "file-type" flags. */
+ assert( eType==SQLITE_OPEN_MAIN_DB || eType==SQLITE_OPEN_TEMP_DB
+ || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL
+ || eType==SQLITE_OPEN_SUBJOURNAL || eType==SQLITE_OPEN_MASTER_JOURNAL
+ || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
+ );
+
+ assert( pFile!=0 );
+ memset(pFile, 0, sizeof(winFile));
+ pFile->h = INVALID_HANDLE_VALUE;
+
+#if SQLITE_OS_WINRT
+ if( !zUtf8Name && !sqlite3_temp_directory ){
+ sqlite3_log(SQLITE_ERROR,
+ "sqlite3_temp_directory variable should be set for WinRT");
+ }
+#endif
+
+ /* If the second argument to this function is NULL, generate a
+ ** temporary file name to use
+ */
+ if( !zUtf8Name ){
+ assert( isDelete && !isOpenJournal );
+ rc = winGetTempname(pVfs, &zTmpname);
+ if( rc!=SQLITE_OK ){
+ OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
+ return rc;
+ }
+ zUtf8Name = zTmpname;
+ }
+
+ /* Database filenames are double-zero terminated if they are not
+ ** URIs with parameters. Hence, they can always be passed into
+ ** sqlite3_uri_parameter().
+ */
+ assert( (eType!=SQLITE_OPEN_MAIN_DB) || (flags & SQLITE_OPEN_URI) ||
+ zUtf8Name[sqlite3Strlen30(zUtf8Name)+1]==0 );
+
+ /* Convert the filename to the system encoding. */
+ zConverted = winConvertFromUtf8Filename(zUtf8Name);
+ if( zConverted==0 ){
+ sqlite3_free(zTmpname);
+ OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
+ return SQLITE_IOERR_NOMEM;
+ }
+
+ if( winIsDir(zConverted) ){
+ sqlite3_free(zConverted);
+ sqlite3_free(zTmpname);
+ OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
+ return SQLITE_CANTOPEN_ISDIR;
+ }
+
+ if( isReadWrite ){
+ dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
+ }else{
+ dwDesiredAccess = GENERIC_READ;
+ }
+
+ /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is
+ ** created. SQLite doesn't use it to indicate "exclusive access"
+ ** as it is usually understood.
+ */
+ if( isExclusive ){
+ /* Creates a new file, only if it does not already exist. */
+ /* If the file exists, it fails. */
+ dwCreationDisposition = CREATE_NEW;
+ }else if( isCreate ){
+ /* Open existing file, or create if it doesn't exist */
+ dwCreationDisposition = OPEN_ALWAYS;
+ }else{
+ /* Opens a file, only if it exists. */
+ dwCreationDisposition = OPEN_EXISTING;
+ }
+
+ dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
+
+ if( isDelete ){
+#if SQLITE_OS_WINCE
+ dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
+ isTemp = 1;
+#else
+ dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
+ | FILE_ATTRIBUTE_HIDDEN
+ | FILE_FLAG_DELETE_ON_CLOSE;
+#endif
+ }else{
+ dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
+ }
+ /* Reports from the internet are that performance is always
+ ** better if FILE_FLAG_RANDOM_ACCESS is used. Ticket #2699. */
+#if SQLITE_OS_WINCE
+ dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
+#endif
+
+ if( osIsNT() ){
+#if SQLITE_OS_WINRT
+ CREATEFILE2_EXTENDED_PARAMETERS extendedParameters;
+ extendedParameters.dwSize = sizeof(CREATEFILE2_EXTENDED_PARAMETERS);
+ extendedParameters.dwFileAttributes =
+ dwFlagsAndAttributes & FILE_ATTRIBUTE_MASK;
+ extendedParameters.dwFileFlags = dwFlagsAndAttributes & FILE_FLAG_MASK;
+ extendedParameters.dwSecurityQosFlags = SECURITY_ANONYMOUS;
+ extendedParameters.lpSecurityAttributes = NULL;
+ extendedParameters.hTemplateFile = NULL;
+ while( (h = osCreateFile2((LPCWSTR)zConverted,
+ dwDesiredAccess,
+ dwShareMode,
+ dwCreationDisposition,
+ &extendedParameters))==INVALID_HANDLE_VALUE &&
+ winRetryIoerr(&cnt, &lastErrno) ){
+ /* Noop */
+ }
+#else
+ while( (h = osCreateFileW((LPCWSTR)zConverted,
+ dwDesiredAccess,
+ dwShareMode, NULL,
+ dwCreationDisposition,
+ dwFlagsAndAttributes,
+ NULL))==INVALID_HANDLE_VALUE &&
+ winRetryIoerr(&cnt, &lastErrno) ){
+ /* Noop */
+ }
+#endif
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ while( (h = osCreateFileA((LPCSTR)zConverted,
+ dwDesiredAccess,
+ dwShareMode, NULL,
+ dwCreationDisposition,
+ dwFlagsAndAttributes,
+ NULL))==INVALID_HANDLE_VALUE &&
+ winRetryIoerr(&cnt, &lastErrno) ){
+ /* Noop */
+ }
+ }
+#endif
+ winLogIoerr(cnt);
+
+ OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
+ dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
+
+ if( h==INVALID_HANDLE_VALUE ){
+ pFile->lastErrno = lastErrno;
+ winLogError(SQLITE_CANTOPEN, pFile->lastErrno, "winOpen", zUtf8Name);
+ sqlite3_free(zConverted);
+ sqlite3_free(zTmpname);
+ if( isReadWrite && !isExclusive ){
+ return winOpen(pVfs, zName, id,
+ ((flags|SQLITE_OPEN_READONLY) &
+ ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
+ pOutFlags);
+ }else{
+ return SQLITE_CANTOPEN_BKPT;
+ }
+ }
+
+ if( pOutFlags ){
+ if( isReadWrite ){
+ *pOutFlags = SQLITE_OPEN_READWRITE;
+ }else{
+ *pOutFlags = SQLITE_OPEN_READONLY;
+ }
+ }
+
+ OSTRACE(("OPEN file=%p, name=%s, access=%lx, pOutFlags=%p, *pOutFlags=%d, "
+ "rc=%s\n", h, zUtf8Name, dwDesiredAccess, pOutFlags, pOutFlags ?
+ *pOutFlags : 0, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
+
+#if SQLITE_OS_WINCE
+ if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
+ && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
+ ){
+ osCloseHandle(h);
+ sqlite3_free(zConverted);
+ sqlite3_free(zTmpname);
+ OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
+ return rc;
+ }
+ if( isTemp ){
+ pFile->zDeleteOnClose = zConverted;
+ }else
+#endif
+ {
+ sqlite3_free(zConverted);
+ }
+
+ sqlite3_free(zTmpname);
+ pFile->pMethod = &winIoMethod;
+ pFile->pVfs = pVfs;
+ pFile->h = h;
+ if( isReadonly ){
+ pFile->ctrlFlags |= WINFILE_RDONLY;
+ }
+ if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
+ pFile->ctrlFlags |= WINFILE_PSOW;
+ }
+ pFile->lastErrno = NO_ERROR;
+ pFile->zPath = zName;
+#if SQLITE_MAX_MMAP_SIZE>0
+ pFile->hMap = NULL;
+ pFile->pMapRegion = 0;
+ pFile->mmapSize = 0;
+ pFile->mmapSizeActual = 0;
+ pFile->mmapSizeMax = sqlite3GlobalConfig.szMmap;
+#endif
+
+ OpenCounter(+1);
+ return rc;
+}
+
+/*
+** Delete the named file.
+**
+** Note that Windows does not allow a file to be deleted if some other
+** process has it open. Sometimes a virus scanner or indexing program
+** will open a journal file shortly after it is created in order to do
+** whatever it does. While this other process is holding the
+** file open, we will be unable to delete it. To work around this
+** problem, we delay 100 milliseconds and try to delete again. Up
+** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
+** up and returning an error.
+*/
+static int winDelete(
+ sqlite3_vfs *pVfs, /* Not used on win32 */
+ const char *zFilename, /* Name of file to delete */
+ int syncDir /* Not used on win32 */
+){
+ int cnt = 0;
+ int rc;
+ DWORD attr;
+ DWORD lastErrno = 0;
+ void *zConverted;
+ UNUSED_PARAMETER(pVfs);
+ UNUSED_PARAMETER(syncDir);
+
+ SimulateIOError(return SQLITE_IOERR_DELETE);
+ OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));
+
+ zConverted = winConvertFromUtf8Filename(zFilename);
+ if( zConverted==0 ){
+ OSTRACE(("DELETE name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
+ return SQLITE_IOERR_NOMEM;
+ }
+ if( osIsNT() ){
+ do {
+#if SQLITE_OS_WINRT
+ WIN32_FILE_ATTRIBUTE_DATA sAttrData;
+ memset(&sAttrData, 0, sizeof(sAttrData));
+ if ( osGetFileAttributesExW(zConverted, GetFileExInfoStandard,
+ &sAttrData) ){
+ attr = sAttrData.dwFileAttributes;
+ }else{
+ lastErrno = osGetLastError();
+ if( lastErrno==ERROR_FILE_NOT_FOUND
+ || lastErrno==ERROR_PATH_NOT_FOUND ){
+ rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ break;
+ }
+#else
+ attr = osGetFileAttributesW(zConverted);
+#endif
+ if ( attr==INVALID_FILE_ATTRIBUTES ){
+ lastErrno = osGetLastError();
+ if( lastErrno==ERROR_FILE_NOT_FOUND
+ || lastErrno==ERROR_PATH_NOT_FOUND ){
+ rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ break;
+ }
+ if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
+ rc = SQLITE_ERROR; /* Files only. */
+ break;
+ }
+ if ( osDeleteFileW(zConverted) ){
+ rc = SQLITE_OK; /* Deleted OK. */
+ break;
+ }
+ if ( !winRetryIoerr(&cnt, &lastErrno) ){
+ rc = SQLITE_ERROR; /* No more retries. */
+ break;
+ }
+ } while(1);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ do {
+ attr = osGetFileAttributesA(zConverted);
+ if ( attr==INVALID_FILE_ATTRIBUTES ){
+ lastErrno = osGetLastError();
+ if( lastErrno==ERROR_FILE_NOT_FOUND
+ || lastErrno==ERROR_PATH_NOT_FOUND ){
+ rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+ }else{
+ rc = SQLITE_ERROR;
+ }
+ break;
+ }
+ if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
+ rc = SQLITE_ERROR; /* Files only. */
+ break;
+ }
+ if ( osDeleteFileA(zConverted) ){
+ rc = SQLITE_OK; /* Deleted OK. */
+ break;
+ }
+ if ( !winRetryIoerr(&cnt, &lastErrno) ){
+ rc = SQLITE_ERROR; /* No more retries. */
+ break;
+ }
+ } while(1);
+ }
+#endif
+ if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
+ rc = winLogError(SQLITE_IOERR_DELETE, lastErrno, "winDelete", zFilename);
+ }else{
+ winLogIoerr(cnt);
+ }
+ sqlite3_free(zConverted);
+ OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
+ return rc;
+}
+
+/*
+** Check the existence and status of a file.
+*/
+static int winAccess(
+ sqlite3_vfs *pVfs, /* Not used on win32 */
+ const char *zFilename, /* Name of file to check */
+ int flags, /* Type of test to make on this file */
+ int *pResOut /* OUT: Result */
+){
+ DWORD attr;
+ int rc = 0;
+ DWORD lastErrno = 0;
+ void *zConverted;
+ UNUSED_PARAMETER(pVfs);
+
+ SimulateIOError( return SQLITE_IOERR_ACCESS; );
+ OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
+ zFilename, flags, pResOut));
+
+ zConverted = winConvertFromUtf8Filename(zFilename);
+ if( zConverted==0 ){
+ OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
+ return SQLITE_IOERR_NOMEM;
+ }
+ if( osIsNT() ){
+ int cnt = 0;
+ WIN32_FILE_ATTRIBUTE_DATA sAttrData;
+ memset(&sAttrData, 0, sizeof(sAttrData));
+ while( !(rc = osGetFileAttributesExW((LPCWSTR)zConverted,
+ GetFileExInfoStandard,
+ &sAttrData)) && winRetryIoerr(&cnt, &lastErrno) ){}
+ if( rc ){
+ /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
+ ** as if it does not exist.
+ */
+ if( flags==SQLITE_ACCESS_EXISTS
+ && sAttrData.nFileSizeHigh==0
+ && sAttrData.nFileSizeLow==0 ){
+ attr = INVALID_FILE_ATTRIBUTES;
+ }else{
+ attr = sAttrData.dwFileAttributes;
+ }
+ }else{
+ winLogIoerr(cnt);
+ if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
+ sqlite3_free(zConverted);
+ return winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess",
+ zFilename);
+ }else{
+ attr = INVALID_FILE_ATTRIBUTES;
+ }
+ }
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ attr = osGetFileAttributesA((char*)zConverted);
+ }
+#endif
+ sqlite3_free(zConverted);
+ switch( flags ){
+ case SQLITE_ACCESS_READ:
+ case SQLITE_ACCESS_EXISTS:
+ rc = attr!=INVALID_FILE_ATTRIBUTES;
+ break;
+ case SQLITE_ACCESS_READWRITE:
+ rc = attr!=INVALID_FILE_ATTRIBUTES &&
+ (attr & FILE_ATTRIBUTE_READONLY)==0;
+ break;
+ default:
+ assert(!"Invalid flags argument");
+ }
+ *pResOut = rc;
+ OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
+ zFilename, pResOut, *pResOut));
+ return SQLITE_OK;
+}
+
+/*
+** Returns non-zero if the specified path name starts with a drive letter
+** followed by a colon character.
+*/
+static BOOL winIsDriveLetterAndColon(
+ const char *zPathname
+){
+ return ( sqlite3Isalpha(zPathname[0]) && zPathname[1]==':' );
+}
+
+/*
+** Returns non-zero if the specified path name should be used verbatim. If
+** non-zero is returned from this function, the calling function must simply
+** use the provided path name verbatim -OR- resolve it into a full path name
+** using the GetFullPathName Win32 API function (if available).
+*/
+static BOOL winIsVerbatimPathname(
+ const char *zPathname
+){
+ /*
+ ** If the path name starts with a forward slash or a backslash, it is either
+ ** a legal UNC name, a volume relative path, or an absolute path name in the
+ ** "Unix" format on Windows. There is no easy way to differentiate between
+ ** the final two cases; therefore, we return the safer return value of TRUE
+ ** so that callers of this function will simply use it verbatim.
+ */
+ if ( winIsDirSep(zPathname[0]) ){
+ return TRUE;
+ }
+
+ /*
+ ** If the path name starts with a letter and a colon it is either a volume
+ ** relative path or an absolute path. Callers of this function must not
+ ** attempt to treat it as a relative path name (i.e. they should simply use
+ ** it verbatim).
+ */
+ if ( winIsDriveLetterAndColon(zPathname) ){
+ return TRUE;
+ }
+
+ /*
+ ** If we get to this point, the path name should almost certainly be a purely
+ ** relative one (i.e. not a UNC name, not absolute, and not volume relative).
+ */
+ return FALSE;
+}
+
+/*
+** Turn a relative pathname into a full pathname. Write the full
+** pathname into zOut[]. zOut[] will be at least pVfs->mxPathname
+** bytes in size.
+*/
+static int winFullPathname(
+ sqlite3_vfs *pVfs, /* Pointer to vfs object */
+ const char *zRelative, /* Possibly relative input path */
+ int nFull, /* Size of output buffer in bytes */
+ char *zFull /* Output buffer */
+){
+
+#if defined(__CYGWIN__)
+ SimulateIOError( return SQLITE_ERROR );
+ UNUSED_PARAMETER(nFull);
+ assert( nFull>=pVfs->mxPathname );
+ if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
+ /*
+ ** NOTE: We are dealing with a relative path name and the data
+ ** directory has been set. Therefore, use it as the basis
+ ** for converting the relative path name to an absolute
+ ** one by prepending the data directory and a slash.
+ */
+ char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
+ if( !zOut ){
+ return SQLITE_IOERR_NOMEM;
+ }
+ if( cygwin_conv_path(
+ (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A) |
+ CCP_RELATIVE, zRelative, zOut, pVfs->mxPathname+1)<0 ){
+ sqlite3_free(zOut);
+ return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
+ "winFullPathname1", zRelative);
+ }else{
+ char *zUtf8 = winConvertToUtf8Filename(zOut);
+ if( !zUtf8 ){
+ sqlite3_free(zOut);
+ return SQLITE_IOERR_NOMEM;
+ }
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
+ sqlite3_data_directory, winGetDirSep(), zUtf8);
+ sqlite3_free(zUtf8);
+ sqlite3_free(zOut);
+ }
+ }else{
+ char *zOut = sqlite3MallocZero( pVfs->mxPathname+1 );
+ if( !zOut ){
+ return SQLITE_IOERR_NOMEM;
+ }
+ if( cygwin_conv_path(
+ (osIsNT() ? CCP_POSIX_TO_WIN_W : CCP_POSIX_TO_WIN_A),
+ zRelative, zOut, pVfs->mxPathname+1)<0 ){
+ sqlite3_free(zOut);
+ return winLogError(SQLITE_CANTOPEN_CONVPATH, (DWORD)errno,
+ "winFullPathname2", zRelative);
+ }else{
+ char *zUtf8 = winConvertToUtf8Filename(zOut);
+ if( !zUtf8 ){
+ sqlite3_free(zOut);
+ return SQLITE_IOERR_NOMEM;
+ }
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zUtf8);
+ sqlite3_free(zUtf8);
+ sqlite3_free(zOut);
+ }
+ }
+ return SQLITE_OK;
+#endif
+
+#if (SQLITE_OS_WINCE || SQLITE_OS_WINRT) && !defined(__CYGWIN__)
+ SimulateIOError( return SQLITE_ERROR );
+ /* WinCE has no concept of a relative pathname, or so I am told. */
+ /* WinRT has no way to convert a relative path to an absolute one. */
+ if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
+ /*
+ ** NOTE: We are dealing with a relative path name and the data
+ ** directory has been set. Therefore, use it as the basis
+ ** for converting the relative path name to an absolute
+ ** one by prepending the data directory and a backslash.
+ */
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
+ sqlite3_data_directory, winGetDirSep(), zRelative);
+ }else{
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zRelative);
+ }
+ return SQLITE_OK;
+#endif
+
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
+ DWORD nByte;
+ void *zConverted;
+ char *zOut;
+
+ /* If this path name begins with "/X:", where "X" is any alphabetic
+ ** character, discard the initial "/" from the pathname.
+ */
+ if( zRelative[0]=='/' && winIsDriveLetterAndColon(zRelative+1) ){
+ zRelative++;
+ }
+
+ /* It's odd to simulate an io-error here, but really this is just
+ ** using the io-error infrastructure to test that SQLite handles this
+ ** function failing. This function could fail if, for example, the
+ ** current working directory has been unlinked.
+ */
+ SimulateIOError( return SQLITE_ERROR );
+ if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
+ /*
+ ** NOTE: We are dealing with a relative path name and the data
+ ** directory has been set. Therefore, use it as the basis
+ ** for converting the relative path name to an absolute
+ ** one by prepending the data directory and a backslash.
+ */
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s%c%s",
+ sqlite3_data_directory, winGetDirSep(), zRelative);
+ return SQLITE_OK;
+ }
+ zConverted = winConvertFromUtf8Filename(zRelative);
+ if( zConverted==0 ){
+ return SQLITE_IOERR_NOMEM;
+ }
+ if( osIsNT() ){
+ LPWSTR zTemp;
+ nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname1", zRelative);
+ }
+ nByte += 3;
+ zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
+ if( zTemp==0 ){
+ sqlite3_free(zConverted);
+ return SQLITE_IOERR_NOMEM;
+ }
+ nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ sqlite3_free(zTemp);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname2", zRelative);
+ }
+ sqlite3_free(zConverted);
+ zOut = winUnicodeToUtf8(zTemp);
+ sqlite3_free(zTemp);
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ char *zTemp;
+ nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname3", zRelative);
+ }
+ nByte += 3;
+ zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
+ if( zTemp==0 ){
+ sqlite3_free(zConverted);
+ return SQLITE_IOERR_NOMEM;
+ }
+ nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
+ if( nByte==0 ){
+ sqlite3_free(zConverted);
+ sqlite3_free(zTemp);
+ return winLogError(SQLITE_CANTOPEN_FULLPATH, osGetLastError(),
+ "winFullPathname4", zRelative);
+ }
+ sqlite3_free(zConverted);
+ zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
+ sqlite3_free(zTemp);
+ }
+#endif
+ if( zOut ){
+ sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s", zOut);
+ sqlite3_free(zOut);
+ return SQLITE_OK;
+ }else{
+ return SQLITE_IOERR_NOMEM;
+ }
+#endif
+}
+
+#ifndef SQLITE_OMIT_LOAD_EXTENSION
+/*
+** Interfaces for opening a shared library, finding entry points
+** within the shared library, and closing the shared library.
+*/
+static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
+ HANDLE h;
+#if defined(__CYGWIN__)
+ int nFull = pVfs->mxPathname+1;
+ char *zFull = sqlite3MallocZero( nFull );
+ void *zConverted = 0;
+ if( zFull==0 ){
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
+ return 0;
+ }
+ if( winFullPathname(pVfs, zFilename, nFull, zFull)!=SQLITE_OK ){
+ sqlite3_free(zFull);
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
+ return 0;
+ }
+ zConverted = winConvertFromUtf8Filename(zFull);
+ sqlite3_free(zFull);
+#else
+ void *zConverted = winConvertFromUtf8Filename(zFilename);
+ UNUSED_PARAMETER(pVfs);
+#endif
+ if( zConverted==0 ){
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)0));
+ return 0;
+ }
+ if( osIsNT() ){
+#if SQLITE_OS_WINRT
+ h = osLoadPackagedLibrary((LPCWSTR)zConverted, 0);
+#else
+ h = osLoadLibraryW((LPCWSTR)zConverted);
+#endif
+ }
+#ifdef SQLITE_WIN32_HAS_ANSI
+ else{
+ h = osLoadLibraryA((char*)zConverted);
+ }
+#endif
+ OSTRACE(("DLOPEN name=%s, handle=%p\n", zFilename, (void*)h));
+ sqlite3_free(zConverted);
+ return (void*)h;
+}
+static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
+ UNUSED_PARAMETER(pVfs);
+ winGetLastErrorMsg(osGetLastError(), nBuf, zBufOut);
+}
+static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
+ FARPROC proc;
+ UNUSED_PARAMETER(pVfs);
+ proc = osGetProcAddressA((HANDLE)pH, zSym);
+ OSTRACE(("DLSYM handle=%p, symbol=%s, address=%p\n",
+ (void*)pH, zSym, (void*)proc));
+ return (void(*)(void))proc;
+}
+static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
+ UNUSED_PARAMETER(pVfs);
+ osFreeLibrary((HANDLE)pHandle);
+ OSTRACE(("DLCLOSE handle=%p\n", (void*)pHandle));
+}
+#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
+ #define winDlOpen 0
+ #define winDlError 0
+ #define winDlSym 0
+ #define winDlClose 0
+#endif
+
+
+/*
+** Write up to nBuf bytes of randomness into zBuf.
+*/
+static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+ int n = 0;
+ UNUSED_PARAMETER(pVfs);
+#if defined(SQLITE_TEST)
+ n = nBuf;
+ memset(zBuf, 0, nBuf);
+#else
+ if( sizeof(SYSTEMTIME)<=nBuf-n ){
+ SYSTEMTIME x;
+ osGetSystemTime(&x);
+ memcpy(&zBuf[n], &x, sizeof(x));
+ n += sizeof(x);
+ }
+ if( sizeof(DWORD)<=nBuf-n ){
+ DWORD pid = osGetCurrentProcessId();
+ memcpy(&zBuf[n], &pid, sizeof(pid));
+ n += sizeof(pid);
+ }
+#if SQLITE_OS_WINRT
+ if( sizeof(ULONGLONG)<=nBuf-n ){
+ ULONGLONG cnt = osGetTickCount64();
+ memcpy(&zBuf[n], &cnt, sizeof(cnt));
+ n += sizeof(cnt);
+ }
+#else
+ if( sizeof(DWORD)<=nBuf-n ){
+ DWORD cnt = osGetTickCount();
+ memcpy(&zBuf[n], &cnt, sizeof(cnt));
+ n += sizeof(cnt);
+ }
+#endif
+ if( sizeof(LARGE_INTEGER)<=nBuf-n ){
+ LARGE_INTEGER i;
+ osQueryPerformanceCounter(&i);
+ memcpy(&zBuf[n], &i, sizeof(i));
+ n += sizeof(i);
+ }
+#endif
+ return n;
+}
+
+
+/*
+** Sleep for a little while. Return the amount of time slept.
+*/
+static int winSleep(sqlite3_vfs *pVfs, int microsec){
+ sqlite3_win32_sleep((microsec+999)/1000);
+ UNUSED_PARAMETER(pVfs);
+ return ((microsec+999)/1000)*1000;
+}
+
+/*
+** The following variable, if set to a non-zero value, is interpreted as
+** the number of seconds since 1970 and is used to set the result of
+** sqlite3OsCurrentTime() during testing.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_current_time = 0; /* Fake system time in seconds since 1970. */
+#endif
+
+/*
+** Find the current time (in Universal Coordinated Time). Write into *piNow
+** the current time and date as a Julian Day number times 86_400_000. In
+** other words, write into *piNow the number of milliseconds since the Julian
+** epoch of noon in Greenwich on November 24, 4714 B.C according to the
+** proleptic Gregorian calendar.
+**
+** On success, return SQLITE_OK. Return SQLITE_ERROR if the time and date
+** cannot be found.
+*/
+static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
+ /* FILETIME structure is a 64-bit value representing the number of
+ 100-nanosecond intervals since January 1, 1601 (= JD 2305813.5).
+ */
+ FILETIME ft;
+ static const sqlite3_int64 winFiletimeEpoch = 23058135*(sqlite3_int64)8640000;
+#ifdef SQLITE_TEST
+ static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
+#endif
+ /* 2^32 - to avoid use of LL and warnings in gcc */
+ static const sqlite3_int64 max32BitValue =
+ (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 +
+ (sqlite3_int64)294967296;
+
+#if SQLITE_OS_WINCE
+ SYSTEMTIME time;
+ osGetSystemTime(&time);
+ /* if SystemTimeToFileTime() fails, it returns zero. */
+ if (!osSystemTimeToFileTime(&time,&ft)){
+ return SQLITE_ERROR;
+ }
+#else
+ osGetSystemTimeAsFileTime( &ft );
+#endif
+
+ *piNow = winFiletimeEpoch +
+ ((((sqlite3_int64)ft.dwHighDateTime)*max32BitValue) +
+ (sqlite3_int64)ft.dwLowDateTime)/(sqlite3_int64)10000;
+
+#ifdef SQLITE_TEST
+ if( sqlite3_current_time ){
+ *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
+ }
+#endif
+ UNUSED_PARAMETER(pVfs);
+ return SQLITE_OK;
+}
+
+/*
+** Find the current time (in Universal Coordinated Time). Write the
+** current time and date as a Julian Day number into *prNow and
+** return 0. Return 1 if the time and date cannot be found.
+*/
+static int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
+ int rc;
+ sqlite3_int64 i;
+ rc = winCurrentTimeInt64(pVfs, &i);
+ if( !rc ){
+ *prNow = i/86400000.0;
+ }
+ return rc;
+}
+
+/*
+** The idea is that this function works like a combination of
+** GetLastError() and FormatMessage() on Windows (or errno and
+** strerror_r() on Unix). After an error is returned by an OS
+** function, SQLite calls this function with zBuf pointing to
+** a buffer of nBuf bytes. The OS layer should populate the
+** buffer with a nul-terminated UTF-8 encoded error message
+** describing the last IO error to have occurred within the calling
+** thread.
+**
+** If the error message is too large for the supplied buffer,
+** it should be truncated. The return value of xGetLastError
+** is zero if the error message fits in the buffer, or non-zero
+** otherwise (if the message was truncated). If non-zero is returned,
+** then it is not necessary to include the nul-terminator character
+** in the output buffer.
+**
+** Not supplying an error message will have no adverse effect
+** on SQLite. It is fine to have an implementation that never
+** returns an error message:
+**
+** int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+** assert(zBuf[0]=='\0');
+** return 0;
+** }
+**
+** However if an error message is supplied, it will be incorporated
+** by sqlite into the error message available to the user using
+** sqlite3_errmsg(), possibly making IO errors easier to debug.
+*/
+static int winGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+ UNUSED_PARAMETER(pVfs);
+ return winGetLastErrorMsg(osGetLastError(), nBuf, zBuf);
+}
+
+/*
+** Initialize and deinitialize the operating system interface.
+*/
+SQLITE_API int sqlite3_os_init(void){
+ static sqlite3_vfs winVfs = {
+ 3, /* iVersion */
+ sizeof(winFile), /* szOsFile */
+ SQLITE_WIN32_MAX_PATH_BYTES, /* mxPathname */
+ 0, /* pNext */
+ "win32", /* zName */
+ 0, /* pAppData */
+ winOpen, /* xOpen */
+ winDelete, /* xDelete */
+ winAccess, /* xAccess */
+ winFullPathname, /* xFullPathname */
+ winDlOpen, /* xDlOpen */
+ winDlError, /* xDlError */
+ winDlSym, /* xDlSym */
+ winDlClose, /* xDlClose */
+ winRandomness, /* xRandomness */
+ winSleep, /* xSleep */
+ winCurrentTime, /* xCurrentTime */
+ winGetLastError, /* xGetLastError */
+ winCurrentTimeInt64, /* xCurrentTimeInt64 */
+ winSetSystemCall, /* xSetSystemCall */
+ winGetSystemCall, /* xGetSystemCall */
+ winNextSystemCall, /* xNextSystemCall */
+ };
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ static sqlite3_vfs winLongPathVfs = {
+ 3, /* iVersion */
+ sizeof(winFile), /* szOsFile */
+ SQLITE_WINNT_MAX_PATH_BYTES, /* mxPathname */
+ 0, /* pNext */
+ "win32-longpath", /* zName */
+ 0, /* pAppData */
+ winOpen, /* xOpen */
+ winDelete, /* xDelete */
+ winAccess, /* xAccess */
+ winFullPathname, /* xFullPathname */
+ winDlOpen, /* xDlOpen */
+ winDlError, /* xDlError */
+ winDlSym, /* xDlSym */
+ winDlClose, /* xDlClose */
+ winRandomness, /* xRandomness */
+ winSleep, /* xSleep */
+ winCurrentTime, /* xCurrentTime */
+ winGetLastError, /* xGetLastError */
+ winCurrentTimeInt64, /* xCurrentTimeInt64 */
+ winSetSystemCall, /* xSetSystemCall */
+ winGetSystemCall, /* xGetSystemCall */
+ winNextSystemCall, /* xNextSystemCall */
+ };
+#endif
+
+ /* Double-check that the aSyscall[] array has been constructed
+ ** correctly. See ticket [bb3a86e890c8e96ab] */
+ assert( ArraySize(aSyscall)==76 );
+
+ /* get memory map allocation granularity */
+ memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
+#if SQLITE_OS_WINRT
+ osGetNativeSystemInfo(&winSysInfo);
+#else
+ osGetSystemInfo(&winSysInfo);
+#endif
+ assert( winSysInfo.dwAllocationGranularity>0 );
+ assert( winSysInfo.dwPageSize>0 );
+
+ sqlite3_vfs_register(&winVfs, 1);
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+ sqlite3_vfs_register(&winLongPathVfs, 0);
+#endif
+
+ return SQLITE_OK;
+}
+
+SQLITE_API int sqlite3_os_end(void){
+#if SQLITE_OS_WINRT
+ if( sleepObj!=NULL ){
+ osCloseHandle(sleepObj);
+ sleepObj = NULL;
+ }
+#endif
+ return SQLITE_OK;
+}
+
+#endif /* SQLITE_OS_WIN */
+
+/************** End of os_win.c **********************************************/
+/************** Begin file bitvec.c ******************************************/
+/*
+** 2008 February 16
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file implements an object that represents a fixed-length
+** bitmap. Bits are numbered starting with 1.
+**
+** A bitmap is used to record which pages of a database file have been
+** journalled during a transaction, or which pages have the "dont-write"
+** property. Usually only a few pages are meet either condition.
+** So the bitmap is usually sparse and has low cardinality.
+** But sometimes (for example when during a DROP of a large table) most
+** or all of the pages in a database can get journalled. In those cases,
+** the bitmap becomes dense with high cardinality. The algorithm needs
+** to handle both cases well.
+**
+** The size of the bitmap is fixed when the object is created.
+**
+** All bits are clear when the bitmap is created. Individual bits
+** may be set or cleared one at a time.
+**
+** Test operations are about 100 times more common that set operations.
+** Clear operations are exceedingly rare. There are usually between
+** 5 and 500 set operations per Bitvec object, though the number of sets can
+** sometimes grow into tens of thousands or larger. The size of the
+** Bitvec object is the number of pages in the database file at the
+** start of a transaction, and is thus usually less than a few thousand,
+** but can be as large as 2 billion for a really big database.
+*/
+
+/* Size of the Bitvec structure in bytes. */
+#define BITVEC_SZ 512
+
+/* Round the union size down to the nearest pointer boundary, since that's how
+** it will be aligned within the Bitvec struct. */
+#define BITVEC_USIZE (((BITVEC_SZ-(3*sizeof(u32)))/sizeof(Bitvec*))*sizeof(Bitvec*))
+
+/* Type of the array "element" for the bitmap representation.
+** Should be a power of 2, and ideally, evenly divide into BITVEC_USIZE.
+** Setting this to the "natural word" size of your CPU may improve
+** performance. */
+#define BITVEC_TELEM u8
+/* Size, in bits, of the bitmap element. */
+#define BITVEC_SZELEM 8
+/* Number of elements in a bitmap array. */
+#define BITVEC_NELEM (BITVEC_USIZE/sizeof(BITVEC_TELEM))
+/* Number of bits in the bitmap array. */
+#define BITVEC_NBIT (BITVEC_NELEM*BITVEC_SZELEM)
+
+/* Number of u32 values in hash table. */
+#define BITVEC_NINT (BITVEC_USIZE/sizeof(u32))
+/* Maximum number of entries in hash table before
+** sub-dividing and re-hashing. */
+#define BITVEC_MXHASH (BITVEC_NINT/2)
+/* Hashing function for the aHash representation.
+** Empirical testing showed that the *37 multiplier
+** (an arbitrary prime)in the hash function provided
+** no fewer collisions than the no-op *1. */
+#define BITVEC_HASH(X) (((X)*1)%BITVEC_NINT)
+
+#define BITVEC_NPTR (BITVEC_USIZE/sizeof(Bitvec *))
+
+
+/*
+** A bitmap is an instance of the following structure.
+**
+** This bitmap records the existence of zero or more bits
+** with values between 1 and iSize, inclusive.
+**
+** There are three possible representations of the bitmap.
+** If iSize<=BITVEC_NBIT, then Bitvec.u.aBitmap[] is a straight
+** bitmap. The least significant bit is bit 1.
+**
+** If iSize>BITVEC_NBIT and iDivisor==0 then Bitvec.u.aHash[] is
+** a hash table that will hold up to BITVEC_MXHASH distinct values.
+**
+** Otherwise, the value i is redirected into one of BITVEC_NPTR
+** sub-bitmaps pointed to by Bitvec.u.apSub[]. Each subbitmap
+** handles up to iDivisor separate values of i. apSub[0] holds
+** values between 1 and iDivisor. apSub[1] holds values between
+** iDivisor+1 and 2*iDivisor. apSub[N] holds values between
+** N*iDivisor+1 and (N+1)*iDivisor. Each subbitmap is normalized
+** to hold deal with values between 1 and iDivisor.
+*/
+struct Bitvec {
+ u32 iSize; /* Maximum bit index. Max iSize is 4,294,967,296. */
+ u32 nSet; /* Number of bits that are set - only valid for aHash
+ ** element. Max is BITVEC_NINT. For BITVEC_SZ of 512,
+ ** this would be 125. */
+ u32 iDivisor; /* Number of bits handled by each apSub[] entry. */
+ /* Should >=0 for apSub element. */
+ /* Max iDivisor is max(u32) / BITVEC_NPTR + 1. */
+ /* For a BITVEC_SZ of 512, this would be 34,359,739. */
+ union {
+ BITVEC_TELEM aBitmap[BITVEC_NELEM]; /* Bitmap representation */
+ u32 aHash[BITVEC_NINT]; /* Hash table representation */
+ Bitvec *apSub[BITVEC_NPTR]; /* Recursive representation */
+ } u;
+};
+
+/*
+** Create a new bitmap object able to handle bits between 0 and iSize,
+** inclusive. Return a pointer to the new object. Return NULL if
+** malloc fails.
+*/
+SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32 iSize){
+ Bitvec *p;
+ assert( sizeof(*p)==BITVEC_SZ );
+ p = sqlite3MallocZero( sizeof(*p) );
+ if( p ){
+ p->iSize = iSize;
+ }
+ return p;
+}
+
+/*
+** Check to see if the i-th bit is set. Return true or false.
+** If p is NULL (if the bitmap has not been created) or if
+** i is out of range, then return false.
+*/
+SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec *p, u32 i){
+ if( p==0 ) return 0;
+ if( i>p->iSize || i==0 ) return 0;
+ i--;
+ while( p->iDivisor ){
+ u32 bin = i/p->iDivisor;
+ i = i%p->iDivisor;
+ p = p->u.apSub[bin];
+ if (!p) {
+ return 0;
+ }
+ }
+ if( p->iSize<=BITVEC_NBIT ){
+ return (p->u.aBitmap[i/BITVEC_SZELEM] & (1<<(i&(BITVEC_SZELEM-1))))!=0;
+ } else{
+ u32 h = BITVEC_HASH(i++);
+ while( p->u.aHash[h] ){
+ if( p->u.aHash[h]==i ) return 1;
+ h = (h+1) % BITVEC_NINT;
+ }
+ return 0;
+ }
+}
+
+/*
+** Set the i-th bit. Return 0 on success and an error code if
+** anything goes wrong.
+**
+** This routine might cause sub-bitmaps to be allocated. Failing
+** to get the memory needed to hold the sub-bitmap is the only
+** that can go wrong with an insert, assuming p and i are valid.
+**
+** The calling function must ensure that p is a valid Bitvec object
+** and that the value for "i" is within range of the Bitvec object.
+** Otherwise the behavior is undefined.
+*/
+SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec *p, u32 i){
+ u32 h;
+ if( p==0 ) return SQLITE_OK;
+ assert( i>0 );
+ assert( i<=p->iSize );
+ i--;
+ while((p->iSize > BITVEC_NBIT) && p->iDivisor) {
+ u32 bin = i/p->iDivisor;
+ i = i%p->iDivisor;
+ if( p->u.apSub[bin]==0 ){
+ p->u.apSub[bin] = sqlite3BitvecCreate( p->iDivisor );
+ if( p->u.apSub[bin]==0 ) return SQLITE_NOMEM;
+ }
+ p = p->u.apSub[bin];
+ }
+ if( p->iSize<=BITVEC_NBIT ){
+ p->u.aBitmap[i/BITVEC_SZELEM] |= 1 << (i&(BITVEC_SZELEM-1));
+ return SQLITE_OK;
+ }
+ h = BITVEC_HASH(i++);
+ /* if there wasn't a hash collision, and this doesn't */
+ /* completely fill the hash, then just add it without */
+ /* worring about sub-dividing and re-hashing. */
+ if( !p->u.aHash[h] ){
+ if (p->nSet<(BITVEC_NINT-1)) {
+ goto bitvec_set_end;
+ } else {
+ goto bitvec_set_rehash;
+ }
+ }
+ /* there was a collision, check to see if it's already */
+ /* in hash, if not, try to find a spot for it */
+ do {
+ if( p->u.aHash[h]==i ) return SQLITE_OK;
+ h++;
+ if( h>=BITVEC_NINT ) h = 0;
+ } while( p->u.aHash[h] );
+ /* we didn't find it in the hash. h points to the first */
+ /* available free spot. check to see if this is going to */
+ /* make our hash too "full". */
+bitvec_set_rehash:
+ if( p->nSet>=BITVEC_MXHASH ){
+ unsigned int j;
+ int rc;
+ u32 *aiValues = sqlite3StackAllocRaw(0, sizeof(p->u.aHash));
+ if( aiValues==0 ){
+ return SQLITE_NOMEM;
+ }else{
+ memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+ memset(p->u.apSub, 0, sizeof(p->u.apSub));
+ p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
+ rc = sqlite3BitvecSet(p, i);
+ for(j=0; jnSet++;
+ p->u.aHash[h] = i;
+ return SQLITE_OK;
+}
+
+/*
+** Clear the i-th bit.
+**
+** pBuf must be a pointer to at least BITVEC_SZ bytes of temporary storage
+** that BitvecClear can use to rebuilt its hash table.
+*/
+SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec *p, u32 i, void *pBuf){
+ if( p==0 ) return;
+ assert( i>0 );
+ i--;
+ while( p->iDivisor ){
+ u32 bin = i/p->iDivisor;
+ i = i%p->iDivisor;
+ p = p->u.apSub[bin];
+ if (!p) {
+ return;
+ }
+ }
+ if( p->iSize<=BITVEC_NBIT ){
+ p->u.aBitmap[i/BITVEC_SZELEM] &= ~(1 << (i&(BITVEC_SZELEM-1)));
+ }else{
+ unsigned int j;
+ u32 *aiValues = pBuf;
+ memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+ memset(p->u.aHash, 0, sizeof(p->u.aHash));
+ p->nSet = 0;
+ for(j=0; jnSet++;
+ while( p->u.aHash[h] ){
+ h++;
+ if( h>=BITVEC_NINT ) h = 0;
+ }
+ p->u.aHash[h] = aiValues[j];
+ }
+ }
+ }
+}
+
+/*
+** Destroy a bitmap object. Reclaim all memory used.
+*/
+SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec *p){
+ if( p==0 ) return;
+ if( p->iDivisor ){
+ unsigned int i;
+ for(i=0; iu.apSub[i]);
+ }
+ }
+ sqlite3_free(p);
+}
+
+/*
+** Return the value of the iSize parameter specified when Bitvec *p
+** was created.
+*/
+SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec *p){
+ return p->iSize;
+}
+
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+/*
+** Let V[] be an array of unsigned characters sufficient to hold
+** up to N bits. Let I be an integer between 0 and N. 0<=I>3] |= (1<<(I&7))
+#define CLEARBIT(V,I) V[I>>3] &= ~(1<<(I&7))
+#define TESTBIT(V,I) (V[I>>3]&(1<<(I&7)))!=0
+
+/*
+** This routine runs an extensive test of the Bitvec code.
+**
+** The input is an array of integers that acts as a program
+** to test the Bitvec. The integers are opcodes followed
+** by 0, 1, or 3 operands, depending on the opcode. Another
+** opcode follows immediately after the last operand.
+**
+** There are 6 opcodes numbered from 0 through 5. 0 is the
+** "halt" opcode and causes the test to end.
+**
+** 0 Halt and return the number of errors
+** 1 N S X Set N bits beginning with S and incrementing by X
+** 2 N S X Clear N bits beginning with S and incrementing by X
+** 3 N Set N randomly chosen bits
+** 4 N Clear N randomly chosen bits
+** 5 N S X Set N bits from S increment X in array only, not in bitvec
+**
+** The opcodes 1 through 4 perform set and clear operations are performed
+** on both a Bitvec object and on a linear array of bits obtained from malloc.
+** Opcode 5 works on the linear array only, not on the Bitvec.
+** Opcode 5 is used to deliberately induce a fault in order to
+** confirm that error detection works.
+**
+** At the conclusion of the test the linear array is compared
+** against the Bitvec object. If there are any differences,
+** an error is returned. If they are the same, zero is returned.
+**
+** If a memory allocation error occurs, return -1.
+*/
+SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int sz, int *aOp){
+ Bitvec *pBitvec = 0;
+ unsigned char *pV = 0;
+ int rc = -1;
+ int i, nx, pc, op;
+ void *pTmpSpace;
+
+ /* Allocate the Bitvec to be tested and a linear array of
+ ** bits to act as the reference */
+ pBitvec = sqlite3BitvecCreate( sz );
+ pV = sqlite3MallocZero( (sz+7)/8 + 1 );
+ pTmpSpace = sqlite3_malloc(BITVEC_SZ);
+ if( pBitvec==0 || pV==0 || pTmpSpace==0 ) goto bitvec_end;
+
+ /* NULL pBitvec tests */
+ sqlite3BitvecSet(0, 1);
+ sqlite3BitvecClear(0, 1, pTmpSpace);
+
+ /* Run the program */
+ pc = 0;
+ while( (op = aOp[pc])!=0 ){
+ switch( op ){
+ case 1:
+ case 2:
+ case 5: {
+ nx = 4;
+ i = aOp[pc+2] - 1;
+ aOp[pc+2] += aOp[pc+3];
+ break;
+ }
+ case 3:
+ case 4:
+ default: {
+ nx = 2;
+ sqlite3_randomness(sizeof(i), &i);
+ break;
+ }
+ }
+ if( (--aOp[pc+1]) > 0 ) nx = 0;
+ pc += nx;
+ i = (i & 0x7fffffff)%sz;
+ if( (op & 1)!=0 ){
+ SETBIT(pV, (i+1));
+ if( op!=5 ){
+ if( sqlite3BitvecSet(pBitvec, i+1) ) goto bitvec_end;
+ }
+ }else{
+ CLEARBIT(pV, (i+1));
+ sqlite3BitvecClear(pBitvec, i+1, pTmpSpace);
+ }
+ }
+
+ /* Test to make sure the linear array exactly matches the
+ ** Bitvec object. Start with the assumption that they do
+ ** match (rc==0). Change rc to non-zero if a discrepancy
+ ** is found.
+ */
+ rc = sqlite3BitvecTest(0,0) + sqlite3BitvecTest(pBitvec, sz+1)
+ + sqlite3BitvecTest(pBitvec, 0)
+ + (sqlite3BitvecSize(pBitvec) - sz);
+ for(i=1; i<=sz; i++){
+ if( (TESTBIT(pV,i))!=sqlite3BitvecTest(pBitvec,i) ){
+ rc = i;
+ break;
+ }
+ }
+
+ /* Free allocated structure */
+bitvec_end:
+ sqlite3_free(pTmpSpace);
+ sqlite3_free(pV);
+ sqlite3BitvecDestroy(pBitvec);
+ return rc;
+}
+#endif /* SQLITE_OMIT_BUILTIN_TEST */
+
+/************** End of bitvec.c **********************************************/
+/************** Begin file pcache.c ******************************************/
+/*
+** 2008 August 05
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file implements that page cache.
+*/
+
+/*
+** A complete page cache is an instance of this structure.
+*/
+struct PCache {
+ PgHdr *pDirty, *pDirtyTail; /* List of dirty pages in LRU order */
+ PgHdr *pSynced; /* Last synced page in dirty page list */
+ int nRef; /* Number of referenced pages */
+ int szCache; /* Configured cache size */
+ int szPage; /* Size of every page in this cache */
+ int szExtra; /* Size of extra space for each page */
+ u8 bPurgeable; /* True if pages are on backing store */
+ u8 eCreate; /* eCreate value for for xFetch() */
+ int (*xStress)(void*,PgHdr*); /* Call to try make a page clean */
+ void *pStress; /* Argument to xStress */
+ sqlite3_pcache *pCache; /* Pluggable cache module */
+ PgHdr *pPage1; /* Reference to page 1 */
+};
+
+/*
+** Some of the assert() macros in this code are too expensive to run
+** even during normal debugging. Use them only rarely on long-running
+** tests. Enable the expensive asserts using the
+** -DSQLITE_ENABLE_EXPENSIVE_ASSERT=1 compile-time option.
+*/
+#ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT
+# define expensive_assert(X) assert(X)
+#else
+# define expensive_assert(X)
+#endif
+
+/********************************** Linked List Management ********************/
+
+#if !defined(NDEBUG) && defined(SQLITE_ENABLE_EXPENSIVE_ASSERT)
+/*
+** Check that the pCache->pSynced variable is set correctly. If it
+** is not, either fail an assert or return zero. Otherwise, return
+** non-zero. This is only used in debugging builds, as follows:
+**
+** expensive_assert( pcacheCheckSynced(pCache) );
+*/
+static int pcacheCheckSynced(PCache *pCache){
+ PgHdr *p;
+ for(p=pCache->pDirtyTail; p!=pCache->pSynced; p=p->pDirtyPrev){
+ assert( p->nRef || (p->flags&PGHDR_NEED_SYNC) );
+ }
+ return (p==0 || p->nRef || (p->flags&PGHDR_NEED_SYNC)==0);
+}
+#endif /* !NDEBUG && SQLITE_ENABLE_EXPENSIVE_ASSERT */
+
+/*
+** Remove page pPage from the list of dirty pages.
+*/
+static void pcacheRemoveFromDirtyList(PgHdr *pPage){
+ PCache *p = pPage->pCache;
+
+ assert( pPage->pDirtyNext || pPage==p->pDirtyTail );
+ assert( pPage->pDirtyPrev || pPage==p->pDirty );
+
+ /* Update the PCache1.pSynced variable if necessary. */
+ if( p->pSynced==pPage ){
+ PgHdr *pSynced = pPage->pDirtyPrev;
+ while( pSynced && (pSynced->flags&PGHDR_NEED_SYNC) ){
+ pSynced = pSynced->pDirtyPrev;
+ }
+ p->pSynced = pSynced;
+ }
+
+ if( pPage->pDirtyNext ){
+ pPage->pDirtyNext->pDirtyPrev = pPage->pDirtyPrev;
+ }else{
+ assert( pPage==p->pDirtyTail );
+ p->pDirtyTail = pPage->pDirtyPrev;
+ }
+ if( pPage->pDirtyPrev ){
+ pPage->pDirtyPrev->pDirtyNext = pPage->pDirtyNext;
+ }else{
+ assert( pPage==p->pDirty );
+ p->pDirty = pPage->pDirtyNext;
+ if( p->pDirty==0 && p->bPurgeable ){
+ assert( p->eCreate==1 );
+ p->eCreate = 2;
+ }
+ }
+ pPage->pDirtyNext = 0;
+ pPage->pDirtyPrev = 0;
+
+ expensive_assert( pcacheCheckSynced(p) );
+}
+
+/*
+** Add page pPage to the head of the dirty list (PCache1.pDirty is set to
+** pPage).
+*/
+static void pcacheAddToDirtyList(PgHdr *pPage){
+ PCache *p = pPage->pCache;
+
+ assert( pPage->pDirtyNext==0 && pPage->pDirtyPrev==0 && p->pDirty!=pPage );
+
+ pPage->pDirtyNext = p->pDirty;
+ if( pPage->pDirtyNext ){
+ assert( pPage->pDirtyNext->pDirtyPrev==0 );
+ pPage->pDirtyNext->pDirtyPrev = pPage;
+ }else if( p->bPurgeable ){
+ assert( p->eCreate==2 );
+ p->eCreate = 1;
+ }
+ p->pDirty = pPage;
+ if( !p->pDirtyTail ){
+ p->pDirtyTail = pPage;
+ }
+ if( !p->pSynced && 0==(pPage->flags&PGHDR_NEED_SYNC) ){
+ p->pSynced = pPage;
+ }
+ expensive_assert( pcacheCheckSynced(p) );
+}
+
+/*
+** Wrapper around the pluggable caches xUnpin method. If the cache is
+** being used for an in-memory database, this function is a no-op.
+*/
+static void pcacheUnpin(PgHdr *p){
+ PCache *pCache = p->pCache;
+ if( pCache->bPurgeable ){
+ if( p->pgno==1 ){
+ pCache->pPage1 = 0;
+ }
+ sqlite3GlobalConfig.pcache2.xUnpin(pCache->pCache, p->pPage, 0);
+ }
+}
+
+/*************************************************** General Interfaces ******
+**
+** Initialize and shutdown the page cache subsystem. Neither of these
+** functions are threadsafe.
+*/
+SQLITE_PRIVATE int sqlite3PcacheInitialize(void){
+ if( sqlite3GlobalConfig.pcache2.xInit==0 ){
+ /* IMPLEMENTATION-OF: R-26801-64137 If the xInit() method is NULL, then the
+ ** built-in default page cache is used instead of the application defined
+ ** page cache. */
+ sqlite3PCacheSetDefault();
+ }
+ return sqlite3GlobalConfig.pcache2.xInit(sqlite3GlobalConfig.pcache2.pArg);
+}
+SQLITE_PRIVATE void sqlite3PcacheShutdown(void){
+ if( sqlite3GlobalConfig.pcache2.xShutdown ){
+ /* IMPLEMENTATION-OF: R-26000-56589 The xShutdown() method may be NULL. */
+ sqlite3GlobalConfig.pcache2.xShutdown(sqlite3GlobalConfig.pcache2.pArg);
+ }
+}
+
+/*
+** Return the size in bytes of a PCache object.
+*/
+SQLITE_PRIVATE int sqlite3PcacheSize(void){ return sizeof(PCache); }
+
+/*
+** Create a new PCache object. Storage space to hold the object
+** has already been allocated and is passed in as the p pointer.
+** The caller discovers how much space needs to be allocated by
+** calling sqlite3PcacheSize().
+*/
+SQLITE_PRIVATE void sqlite3PcacheOpen(
+ int szPage, /* Size of every page */
+ int szExtra, /* Extra space associated with each page */
+ int bPurgeable, /* True if pages are on backing store */
+ int (*xStress)(void*,PgHdr*),/* Call to try to make pages clean */
+ void *pStress, /* Argument to xStress */
+ PCache *p /* Preallocated space for the PCache */
+){
+ memset(p, 0, sizeof(PCache));
+ p->szPage = szPage;
+ p->szExtra = szExtra;
+ p->bPurgeable = bPurgeable;
+ p->eCreate = 2;
+ p->xStress = xStress;
+ p->pStress = pStress;
+ p->szCache = 100;
+}
+
+/*
+** Change the page size for PCache object. The caller must ensure that there
+** are no outstanding page references when this function is called.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetPageSize(PCache *pCache, int szPage){
+ assert( pCache->nRef==0 && pCache->pDirty==0 );
+ if( pCache->pCache ){
+ sqlite3GlobalConfig.pcache2.xDestroy(pCache->pCache);
+ pCache->pCache = 0;
+ pCache->pPage1 = 0;
+ }
+ pCache->szPage = szPage;
+}
+
+/*
+** Compute the number of pages of cache requested.
+*/
+static int numberOfCachePages(PCache *p){
+ if( p->szCache>=0 ){
+ return p->szCache;
+ }else{
+ return (int)((-1024*(i64)p->szCache)/(p->szPage+p->szExtra));
+ }
+}
+
+/*
+** Try to obtain a page from the cache.
+*/
+SQLITE_PRIVATE int sqlite3PcacheFetch(
+ PCache *pCache, /* Obtain the page from this cache */
+ Pgno pgno, /* Page number to obtain */
+ int createFlag, /* If true, create page if it does not exist already */
+ PgHdr **ppPage /* Write the page here */
+){
+ sqlite3_pcache_page *pPage;
+ PgHdr *pPgHdr = 0;
+ int eCreate;
+
+ assert( pCache!=0 );
+ assert( createFlag==1 || createFlag==0 );
+ assert( pgno>0 );
+
+ /* If the pluggable cache (sqlite3_pcache*) has not been allocated,
+ ** allocate it now.
+ */
+ if( !pCache->pCache ){
+ sqlite3_pcache *p;
+ if( !createFlag ){
+ *ppPage = 0;
+ return SQLITE_OK;
+ }
+ p = sqlite3GlobalConfig.pcache2.xCreate(
+ pCache->szPage, pCache->szExtra + sizeof(PgHdr), pCache->bPurgeable
+ );
+ if( !p ){
+ return SQLITE_NOMEM;
+ }
+ sqlite3GlobalConfig.pcache2.xCachesize(p, numberOfCachePages(pCache));
+ pCache->pCache = p;
+ }
+
+ /* eCreate defines what to do if the page does not exist.
+ ** 0 Do not allocate a new page. (createFlag==0)
+ ** 1 Allocate a new page if doing so is inexpensive.
+ ** (createFlag==1 AND bPurgeable AND pDirty)
+ ** 2 Allocate a new page even it doing so is difficult.
+ ** (createFlag==1 AND !(bPurgeable AND pDirty)
+ */
+ eCreate = createFlag==0 ? 0 : pCache->eCreate;
+ assert( (createFlag*(1+(!pCache->bPurgeable||!pCache->pDirty)))==eCreate );
+ pPage = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, eCreate);
+ if( !pPage && eCreate==1 ){
+ PgHdr *pPg;
+
+ /* Find a dirty page to write-out and recycle. First try to find a
+ ** page that does not require a journal-sync (one with PGHDR_NEED_SYNC
+ ** cleared), but if that is not possible settle for any other
+ ** unreferenced dirty page.
+ */
+ expensive_assert( pcacheCheckSynced(pCache) );
+ for(pPg=pCache->pSynced;
+ pPg && (pPg->nRef || (pPg->flags&PGHDR_NEED_SYNC));
+ pPg=pPg->pDirtyPrev
+ );
+ pCache->pSynced = pPg;
+ if( !pPg ){
+ for(pPg=pCache->pDirtyTail; pPg && pPg->nRef; pPg=pPg->pDirtyPrev);
+ }
+ if( pPg ){
+ int rc;
+#ifdef SQLITE_LOG_CACHE_SPILL
+ sqlite3_log(SQLITE_FULL,
+ "spill page %d making room for %d - cache used: %d/%d",
+ pPg->pgno, pgno,
+ sqlite3GlobalConfig.pcache.xPagecount(pCache->pCache),
+ numberOfCachePages(pCache));
+#endif
+ rc = pCache->xStress(pCache->pStress, pPg);
+ if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){
+ return rc;
+ }
+ }
+
+ pPage = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, 2);
+ }
+
+ if( pPage ){
+ pPgHdr = (PgHdr *)pPage->pExtra;
+
+ if( !pPgHdr->pPage ){
+ memset(pPgHdr, 0, sizeof(PgHdr));
+ pPgHdr->pPage = pPage;
+ pPgHdr->pData = pPage->pBuf;
+ pPgHdr->pExtra = (void *)&pPgHdr[1];
+ memset(pPgHdr->pExtra, 0, pCache->szExtra);
+ pPgHdr->pCache = pCache;
+ pPgHdr->pgno = pgno;
+ }
+ assert( pPgHdr->pCache==pCache );
+ assert( pPgHdr->pgno==pgno );
+ assert( pPgHdr->pData==pPage->pBuf );
+ assert( pPgHdr->pExtra==(void *)&pPgHdr[1] );
+
+ if( 0==pPgHdr->nRef ){
+ pCache->nRef++;
+ }
+ pPgHdr->nRef++;
+ if( pgno==1 ){
+ pCache->pPage1 = pPgHdr;
+ }
+ }
+ *ppPage = pPgHdr;
+ return (pPgHdr==0 && eCreate) ? SQLITE_NOMEM : SQLITE_OK;
+}
+
+/*
+** Decrement the reference count on a page. If the page is clean and the
+** reference count drops to 0, then it is made elible for recycling.
+*/
+SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr *p){
+ assert( p->nRef>0 );
+ p->nRef--;
+ if( p->nRef==0 ){
+ PCache *pCache = p->pCache;
+ pCache->nRef--;
+ if( (p->flags&PGHDR_DIRTY)==0 ){
+ pcacheUnpin(p);
+ }else{
+ /* Move the page to the head of the dirty list. */
+ pcacheRemoveFromDirtyList(p);
+ pcacheAddToDirtyList(p);
+ }
+ }
+}
+
+/*
+** Increase the reference count of a supplied page by 1.
+*/
+SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr *p){
+ assert(p->nRef>0);
+ p->nRef++;
+}
+
+/*
+** Drop a page from the cache. There must be exactly one reference to the
+** page. This function deletes that reference, so after it returns the
+** page pointed to by p is invalid.
+*/
+SQLITE_PRIVATE void sqlite3PcacheDrop(PgHdr *p){
+ PCache *pCache;
+ assert( p->nRef==1 );
+ if( p->flags&PGHDR_DIRTY ){
+ pcacheRemoveFromDirtyList(p);
+ }
+ pCache = p->pCache;
+ pCache->nRef--;
+ if( p->pgno==1 ){
+ pCache->pPage1 = 0;
+ }
+ sqlite3GlobalConfig.pcache2.xUnpin(pCache->pCache, p->pPage, 1);
+}
+
+/*
+** Make sure the page is marked as dirty. If it isn't dirty already,
+** make it so.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMakeDirty(PgHdr *p){
+ p->flags &= ~PGHDR_DONT_WRITE;
+ assert( p->nRef>0 );
+ if( 0==(p->flags & PGHDR_DIRTY) ){
+ p->flags |= PGHDR_DIRTY;
+ pcacheAddToDirtyList( p);
+ }
+}
+
+/*
+** Make sure the page is marked as clean. If it isn't clean already,
+** make it so.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMakeClean(PgHdr *p){
+ if( (p->flags & PGHDR_DIRTY) ){
+ pcacheRemoveFromDirtyList(p);
+ p->flags &= ~(PGHDR_DIRTY|PGHDR_NEED_SYNC);
+ if( p->nRef==0 ){
+ pcacheUnpin(p);
+ }
+ }
+}
+
+/*
+** Make every page in the cache clean.
+*/
+SQLITE_PRIVATE void sqlite3PcacheCleanAll(PCache *pCache){
+ PgHdr *p;
+ while( (p = pCache->pDirty)!=0 ){
+ sqlite3PcacheMakeClean(p);
+ }
+}
+
+/*
+** Clear the PGHDR_NEED_SYNC flag from all dirty pages.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClearSyncFlags(PCache *pCache){
+ PgHdr *p;
+ for(p=pCache->pDirty; p; p=p->pDirtyNext){
+ p->flags &= ~PGHDR_NEED_SYNC;
+ }
+ pCache->pSynced = pCache->pDirtyTail;
+}
+
+/*
+** Change the page number of page p to newPgno.
+*/
+SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
+ PCache *pCache = p->pCache;
+ assert( p->nRef>0 );
+ assert( newPgno>0 );
+ sqlite3GlobalConfig.pcache2.xRekey(pCache->pCache, p->pPage, p->pgno,newPgno);
+ p->pgno = newPgno;
+ if( (p->flags&PGHDR_DIRTY) && (p->flags&PGHDR_NEED_SYNC) ){
+ pcacheRemoveFromDirtyList(p);
+ pcacheAddToDirtyList(p);
+ }
+}
+
+/*
+** Drop every cache entry whose page number is greater than "pgno". The
+** caller must ensure that there are no outstanding references to any pages
+** other than page 1 with a page number greater than pgno.
+**
+** If there is a reference to page 1 and the pgno parameter passed to this
+** function is 0, then the data area associated with page 1 is zeroed, but
+** the page object is not dropped.
+*/
+SQLITE_PRIVATE void sqlite3PcacheTruncate(PCache *pCache, Pgno pgno){
+ if( pCache->pCache ){
+ PgHdr *p;
+ PgHdr *pNext;
+ for(p=pCache->pDirty; p; p=pNext){
+ pNext = p->pDirtyNext;
+ /* This routine never gets call with a positive pgno except right
+ ** after sqlite3PcacheCleanAll(). So if there are dirty pages,
+ ** it must be that pgno==0.
+ */
+ assert( p->pgno>0 );
+ if( ALWAYS(p->pgno>pgno) ){
+ assert( p->flags&PGHDR_DIRTY );
+ sqlite3PcacheMakeClean(p);
+ }
+ }
+ if( pgno==0 && pCache->pPage1 ){
+ memset(pCache->pPage1->pData, 0, pCache->szPage);
+ pgno = 1;
+ }
+ sqlite3GlobalConfig.pcache2.xTruncate(pCache->pCache, pgno+1);
+ }
+}
+
+/*
+** Close a cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClose(PCache *pCache){
+ if( pCache->pCache ){
+ sqlite3GlobalConfig.pcache2.xDestroy(pCache->pCache);
+ }
+}
+
+/*
+** Discard the contents of the cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheClear(PCache *pCache){
+ sqlite3PcacheTruncate(pCache, 0);
+}
+
+/*
+** Merge two lists of pages connected by pDirty and in pgno order.
+** Do not both fixing the pDirtyPrev pointers.
+*/
+static PgHdr *pcacheMergeDirtyList(PgHdr *pA, PgHdr *pB){
+ PgHdr result, *pTail;
+ pTail = &result;
+ while( pA && pB ){
+ if( pA->pgnopgno ){
+ pTail->pDirty = pA;
+ pTail = pA;
+ pA = pA->pDirty;
+ }else{
+ pTail->pDirty = pB;
+ pTail = pB;
+ pB = pB->pDirty;
+ }
+ }
+ if( pA ){
+ pTail->pDirty = pA;
+ }else if( pB ){
+ pTail->pDirty = pB;
+ }else{
+ pTail->pDirty = 0;
+ }
+ return result.pDirty;
+}
+
+/*
+** Sort the list of pages in accending order by pgno. Pages are
+** connected by pDirty pointers. The pDirtyPrev pointers are
+** corrupted by this sort.
+**
+** Since there cannot be more than 2^31 distinct pages in a database,
+** there cannot be more than 31 buckets required by the merge sorter.
+** One extra bucket is added to catch overflow in case something
+** ever changes to make the previous sentence incorrect.
+*/
+#define N_SORT_BUCKET 32
+static PgHdr *pcacheSortDirtyList(PgHdr *pIn){
+ PgHdr *a[N_SORT_BUCKET], *p;
+ int i;
+ memset(a, 0, sizeof(a));
+ while( pIn ){
+ p = pIn;
+ pIn = p->pDirty;
+ p->pDirty = 0;
+ for(i=0; ALWAYS(ipDirty; p; p=p->pDirtyNext){
+ p->pDirty = p->pDirtyNext;
+ }
+ return pcacheSortDirtyList(pCache->pDirty);
+}
+
+/*
+** Return the total number of referenced pages held by the cache.
+*/
+SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache *pCache){
+ return pCache->nRef;
+}
+
+/*
+** Return the number of references to the page supplied as an argument.
+*/
+SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr *p){
+ return p->nRef;
+}
+
+/*
+** Return the total number of pages in the cache.
+*/
+SQLITE_PRIVATE int sqlite3PcachePagecount(PCache *pCache){
+ int nPage = 0;
+ if( pCache->pCache ){
+ nPage = sqlite3GlobalConfig.pcache2.xPagecount(pCache->pCache);
+ }
+ return nPage;
+}
+
+#ifdef SQLITE_TEST
+/*
+** Get the suggested cache-size value.
+*/
+SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *pCache){
+ return numberOfCachePages(pCache);
+}
+#endif
+
+/*
+** Set the suggested cache-size value.
+*/
+SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage){
+ pCache->szCache = mxPage;
+ if( pCache->pCache ){
+ sqlite3GlobalConfig.pcache2.xCachesize(pCache->pCache,
+ numberOfCachePages(pCache));
+ }
+}
+
+/*
+** Free up as much memory as possible from the page cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheShrink(PCache *pCache){
+ if( pCache->pCache ){
+ sqlite3GlobalConfig.pcache2.xShrink(pCache->pCache);
+ }
+}
+
+#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
+/*
+** For all dirty pages currently in the cache, invoke the specified
+** callback. This is only used if the SQLITE_CHECK_PAGES macro is
+** defined.
+*/
+SQLITE_PRIVATE void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *)){
+ PgHdr *pDirty;
+ for(pDirty=pCache->pDirty; pDirty; pDirty=pDirty->pDirtyNext){
+ xIter(pDirty);
+ }
+}
+#endif
+
+/************** End of pcache.c **********************************************/
+/************** Begin file pcache1.c *****************************************/
+/*
+** 2008 November 05
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements the default page cache implementation (the
+** sqlite3_pcache interface). It also contains part of the implementation
+** of the SQLITE_CONFIG_PAGECACHE and sqlite3_release_memory() features.
+** If the default page cache implementation is overriden, then neither of
+** these two features are available.
+*/
+
+
+typedef struct PCache1 PCache1;
+typedef struct PgHdr1 PgHdr1;
+typedef struct PgFreeslot PgFreeslot;
+typedef struct PGroup PGroup;
+
+/* Each page cache (or PCache) belongs to a PGroup. A PGroup is a set
+** of one or more PCaches that are able to recycle each others unpinned
+** pages when they are under memory pressure. A PGroup is an instance of
+** the following object.
+**
+** This page cache implementation works in one of two modes:
+**
+** (1) Every PCache is the sole member of its own PGroup. There is
+** one PGroup per PCache.
+**
+** (2) There is a single global PGroup that all PCaches are a member
+** of.
+**
+** Mode 1 uses more memory (since PCache instances are not able to rob
+** unused pages from other PCaches) but it also operates without a mutex,
+** and is therefore often faster. Mode 2 requires a mutex in order to be
+** threadsafe, but recycles pages more efficiently.
+**
+** For mode (1), PGroup.mutex is NULL. For mode (2) there is only a single
+** PGroup which is the pcache1.grp global variable and its mutex is
+** SQLITE_MUTEX_STATIC_LRU.
+*/
+struct PGroup {
+ sqlite3_mutex *mutex; /* MUTEX_STATIC_LRU or NULL */
+ unsigned int nMaxPage; /* Sum of nMax for purgeable caches */
+ unsigned int nMinPage; /* Sum of nMin for purgeable caches */
+ unsigned int mxPinned; /* nMaxpage + 10 - nMinPage */
+ unsigned int nCurrentPage; /* Number of purgeable pages allocated */
+ PgHdr1 *pLruHead, *pLruTail; /* LRU list of unpinned pages */
+};
+
+/* Each page cache is an instance of the following object. Every
+** open database file (including each in-memory database and each
+** temporary or transient database) has a single page cache which
+** is an instance of this object.
+**
+** Pointers to structures of this type are cast and returned as
+** opaque sqlite3_pcache* handles.
+*/
+struct PCache1 {
+ /* Cache configuration parameters. Page size (szPage) and the purgeable
+ ** flag (bPurgeable) are set when the cache is created. nMax may be
+ ** modified at any time by a call to the pcache1Cachesize() method.
+ ** The PGroup mutex must be held when accessing nMax.
+ */
+ PGroup *pGroup; /* PGroup this cache belongs to */
+ int szPage; /* Size of allocated pages in bytes */
+ int szExtra; /* Size of extra space in bytes */
+ int bPurgeable; /* True if cache is purgeable */
+ unsigned int nMin; /* Minimum number of pages reserved */
+ unsigned int nMax; /* Configured "cache_size" value */
+ unsigned int n90pct; /* nMax*9/10 */
+ unsigned int iMaxKey; /* Largest key seen since xTruncate() */
+
+ /* Hash table of all pages. The following variables may only be accessed
+ ** when the accessor is holding the PGroup mutex.
+ */
+ unsigned int nRecyclable; /* Number of pages in the LRU list */
+ unsigned int nPage; /* Total number of pages in apHash */
+ unsigned int nHash; /* Number of slots in apHash[] */
+ PgHdr1 **apHash; /* Hash table for fast lookup by key */
+};
+
+/*
+** Each cache entry is represented by an instance of the following
+** structure. Unless SQLITE_PCACHE_SEPARATE_HEADER is defined, a buffer of
+** PgHdr1.pCache->szPage bytes is allocated directly before this structure
+** in memory.
+*/
+struct PgHdr1 {
+ sqlite3_pcache_page page;
+ unsigned int iKey; /* Key value (page number) */
+ u8 isPinned; /* Page in use, not on the LRU list */
+ PgHdr1 *pNext; /* Next in hash table chain */
+ PCache1 *pCache; /* Cache that currently owns this page */
+ PgHdr1 *pLruNext; /* Next in LRU list of unpinned pages */
+ PgHdr1 *pLruPrev; /* Previous in LRU list of unpinned pages */
+};
+
+/*
+** Free slots in the allocator used to divide up the buffer provided using
+** the SQLITE_CONFIG_PAGECACHE mechanism.
+*/
+struct PgFreeslot {
+ PgFreeslot *pNext; /* Next free slot */
+};
+
+/*
+** Global data used by this cache.
+*/
+static SQLITE_WSD struct PCacheGlobal {
+ PGroup grp; /* The global PGroup for mode (2) */
+
+ /* Variables related to SQLITE_CONFIG_PAGECACHE settings. The
+ ** szSlot, nSlot, pStart, pEnd, nReserve, and isInit values are all
+ ** fixed at sqlite3_initialize() time and do not require mutex protection.
+ ** The nFreeSlot and pFree values do require mutex protection.
+ */
+ int isInit; /* True if initialized */
+ int szSlot; /* Size of each free slot */
+ int nSlot; /* The number of pcache slots */
+ int nReserve; /* Try to keep nFreeSlot above this */
+ void *pStart, *pEnd; /* Bounds of pagecache malloc range */
+ /* Above requires no mutex. Use mutex below for variable that follow. */
+ sqlite3_mutex *mutex; /* Mutex for accessing the following: */
+ PgFreeslot *pFree; /* Free page blocks */
+ int nFreeSlot; /* Number of unused pcache slots */
+ /* The following value requires a mutex to change. We skip the mutex on
+ ** reading because (1) most platforms read a 32-bit integer atomically and
+ ** (2) even if an incorrect value is read, no great harm is done since this
+ ** is really just an optimization. */
+ int bUnderPressure; /* True if low on PAGECACHE memory */
+} pcache1_g;
+
+/*
+** All code in this file should access the global structure above via the
+** alias "pcache1". This ensures that the WSD emulation is used when
+** compiling for systems that do not support real WSD.
+*/
+#define pcache1 (GLOBAL(struct PCacheGlobal, pcache1_g))
+
+/*
+** Macros to enter and leave the PCache LRU mutex.
+*/
+#define pcache1EnterMutex(X) sqlite3_mutex_enter((X)->mutex)
+#define pcache1LeaveMutex(X) sqlite3_mutex_leave((X)->mutex)
+
+/******************************************************************************/
+/******** Page Allocation/SQLITE_CONFIG_PCACHE Related Functions **************/
+
+/*
+** This function is called during initialization if a static buffer is
+** supplied to use for the page-cache by passing the SQLITE_CONFIG_PAGECACHE
+** verb to sqlite3_config(). Parameter pBuf points to an allocation large
+** enough to contain 'n' buffers of 'sz' bytes each.
+**
+** This routine is called from sqlite3_initialize() and so it is guaranteed
+** to be serialized already. There is no need for further mutexing.
+*/
+SQLITE_PRIVATE void sqlite3PCacheBufferSetup(void *pBuf, int sz, int n){
+ if( pcache1.isInit ){
+ PgFreeslot *p;
+ sz = ROUNDDOWN8(sz);
+ pcache1.szSlot = sz;
+ pcache1.nSlot = pcache1.nFreeSlot = n;
+ pcache1.nReserve = n>90 ? 10 : (n/10 + 1);
+ pcache1.pStart = pBuf;
+ pcache1.pFree = 0;
+ pcache1.bUnderPressure = 0;
+ while( n-- ){
+ p = (PgFreeslot*)pBuf;
+ p->pNext = pcache1.pFree;
+ pcache1.pFree = p;
+ pBuf = (void*)&((char*)pBuf)[sz];
+ }
+ pcache1.pEnd = pBuf;
+ }
+}
+
+/*
+** Malloc function used within this file to allocate space from the buffer
+** configured using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no
+** such buffer exists or there is no space left in it, this function falls
+** back to sqlite3Malloc().
+**
+** Multiple threads can run this routine at the same time. Global variables
+** in pcache1 need to be protected via mutex.
+*/
+static void *pcache1Alloc(int nByte){
+ void *p = 0;
+ assert( sqlite3_mutex_notheld(pcache1.grp.mutex) );
+ sqlite3StatusSet(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
+ if( nByte<=pcache1.szSlot ){
+ sqlite3_mutex_enter(pcache1.mutex);
+ p = (PgHdr1 *)pcache1.pFree;
+ if( p ){
+ pcache1.pFree = pcache1.pFree->pNext;
+ pcache1.nFreeSlot--;
+ pcache1.bUnderPressure = pcache1.nFreeSlot=0 );
+ sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_USED, 1);
+ }
+ sqlite3_mutex_leave(pcache1.mutex);
+ }
+ if( p==0 ){
+ /* Memory is not available in the SQLITE_CONFIG_PAGECACHE pool. Get
+ ** it from sqlite3Malloc instead.
+ */
+ p = sqlite3Malloc(nByte);
+#ifndef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS
+ if( p ){
+ int sz = sqlite3MallocSize(p);
+ sqlite3_mutex_enter(pcache1.mutex);
+ sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_OVERFLOW, sz);
+ sqlite3_mutex_leave(pcache1.mutex);
+ }
+#endif
+ sqlite3MemdebugSetType(p, MEMTYPE_PCACHE);
+ }
+ return p;
+}
+
+/*
+** Free an allocated buffer obtained from pcache1Alloc().
+*/
+static int pcache1Free(void *p){
+ int nFreed = 0;
+ if( p==0 ) return 0;
+ if( p>=pcache1.pStart && ppNext = pcache1.pFree;
+ pcache1.pFree = pSlot;
+ pcache1.nFreeSlot++;
+ pcache1.bUnderPressure = pcache1.nFreeSlot=pcache1.pStart && ppGroup->mutex) );
+ pcache1LeaveMutex(pCache->pGroup);
+#ifdef SQLITE_PCACHE_SEPARATE_HEADER
+ pPg = pcache1Alloc(pCache->szPage);
+ p = sqlite3Malloc(sizeof(PgHdr1) + pCache->szExtra);
+ if( !pPg || !p ){
+ pcache1Free(pPg);
+ sqlite3_free(p);
+ pPg = 0;
+ }
+#else
+ pPg = pcache1Alloc(sizeof(PgHdr1) + pCache->szPage + pCache->szExtra);
+ p = (PgHdr1 *)&((u8 *)pPg)[pCache->szPage];
+#endif
+ pcache1EnterMutex(pCache->pGroup);
+
+ if( pPg ){
+ p->page.pBuf = pPg;
+ p->page.pExtra = &p[1];
+ if( pCache->bPurgeable ){
+ pCache->pGroup->nCurrentPage++;
+ }
+ return p;
+ }
+ return 0;
+}
+
+/*
+** Free a page object allocated by pcache1AllocPage().
+**
+** The pointer is allowed to be NULL, which is prudent. But it turns out
+** that the current implementation happens to never call this routine
+** with a NULL pointer, so we mark the NULL test with ALWAYS().
+*/
+static void pcache1FreePage(PgHdr1 *p){
+ if( ALWAYS(p) ){
+ PCache1 *pCache = p->pCache;
+ assert( sqlite3_mutex_held(p->pCache->pGroup->mutex) );
+ pcache1Free(p->page.pBuf);
+#ifdef SQLITE_PCACHE_SEPARATE_HEADER
+ sqlite3_free(p);
+#endif
+ if( pCache->bPurgeable ){
+ pCache->pGroup->nCurrentPage--;
+ }
+ }
+}
+
+/*
+** Malloc function used by SQLite to obtain space from the buffer configured
+** using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no such buffer
+** exists, this function falls back to sqlite3Malloc().
+*/
+SQLITE_PRIVATE void *sqlite3PageMalloc(int sz){
+ return pcache1Alloc(sz);
+}
+
+/*
+** Free an allocated buffer obtained from sqlite3PageMalloc().
+*/
+SQLITE_PRIVATE void sqlite3PageFree(void *p){
+ pcache1Free(p);
+}
+
+
+/*
+** Return true if it desirable to avoid allocating a new page cache
+** entry.
+**
+** If memory was allocated specifically to the page cache using
+** SQLITE_CONFIG_PAGECACHE but that memory has all been used, then
+** it is desirable to avoid allocating a new page cache entry because
+** presumably SQLITE_CONFIG_PAGECACHE was suppose to be sufficient
+** for all page cache needs and we should not need to spill the
+** allocation onto the heap.
+**
+** Or, the heap is used for all page cache memory but the heap is
+** under memory pressure, then again it is desirable to avoid
+** allocating a new page cache entry in order to avoid stressing
+** the heap even further.
+*/
+static int pcache1UnderMemoryPressure(PCache1 *pCache){
+ if( pcache1.nSlot && (pCache->szPage+pCache->szExtra)<=pcache1.szSlot ){
+ return pcache1.bUnderPressure;
+ }else{
+ return sqlite3HeapNearlyFull();
+ }
+}
+
+/******************************************************************************/
+/******** General Implementation Functions ************************************/
+
+/*
+** This function is used to resize the hash table used by the cache passed
+** as the first argument.
+**
+** The PCache mutex must be held when this function is called.
+*/
+static int pcache1ResizeHash(PCache1 *p){
+ PgHdr1 **apNew;
+ unsigned int nNew;
+ unsigned int i;
+
+ assert( sqlite3_mutex_held(p->pGroup->mutex) );
+
+ nNew = p->nHash*2;
+ if( nNew<256 ){
+ nNew = 256;
+ }
+
+ pcache1LeaveMutex(p->pGroup);
+ if( p->nHash ){ sqlite3BeginBenignMalloc(); }
+ apNew = (PgHdr1 **)sqlite3MallocZero(sizeof(PgHdr1 *)*nNew);
+ if( p->nHash ){ sqlite3EndBenignMalloc(); }
+ pcache1EnterMutex(p->pGroup);
+ if( apNew ){
+ for(i=0; inHash; i++){
+ PgHdr1 *pPage;
+ PgHdr1 *pNext = p->apHash[i];
+ while( (pPage = pNext)!=0 ){
+ unsigned int h = pPage->iKey % nNew;
+ pNext = pPage->pNext;
+ pPage->pNext = apNew[h];
+ apNew[h] = pPage;
+ }
+ }
+ sqlite3_free(p->apHash);
+ p->apHash = apNew;
+ p->nHash = nNew;
+ }
+
+ return (p->apHash ? SQLITE_OK : SQLITE_NOMEM);
+}
+
+/*
+** This function is used internally to remove the page pPage from the
+** PGroup LRU list, if is part of it. If pPage is not part of the PGroup
+** LRU list, then this function is a no-op.
+**
+** The PGroup mutex must be held when this function is called.
+*/
+static void pcache1PinPage(PgHdr1 *pPage){
+ PCache1 *pCache;
+ PGroup *pGroup;
+
+ assert( pPage!=0 );
+ assert( pPage->isPinned==0 );
+ pCache = pPage->pCache;
+ pGroup = pCache->pGroup;
+ assert( pPage->pLruNext || pPage==pGroup->pLruTail );
+ assert( pPage->pLruPrev || pPage==pGroup->pLruHead );
+ assert( sqlite3_mutex_held(pGroup->mutex) );
+ if( pPage->pLruPrev ){
+ pPage->pLruPrev->pLruNext = pPage->pLruNext;
+ }else{
+ pGroup->pLruHead = pPage->pLruNext;
+ }
+ if( pPage->pLruNext ){
+ pPage->pLruNext->pLruPrev = pPage->pLruPrev;
+ }else{
+ pGroup->pLruTail = pPage->pLruPrev;
+ }
+ pPage->pLruNext = 0;
+ pPage->pLruPrev = 0;
+ pPage->isPinned = 1;
+ pCache->nRecyclable--;
+}
+
+
+/*
+** Remove the page supplied as an argument from the hash table
+** (PCache1.apHash structure) that it is currently stored in.
+**
+** The PGroup mutex must be held when this function is called.
+*/
+static void pcache1RemoveFromHash(PgHdr1 *pPage){
+ unsigned int h;
+ PCache1 *pCache = pPage->pCache;
+ PgHdr1 **pp;
+
+ assert( sqlite3_mutex_held(pCache->pGroup->mutex) );
+ h = pPage->iKey % pCache->nHash;
+ for(pp=&pCache->apHash[h]; (*pp)!=pPage; pp=&(*pp)->pNext);
+ *pp = (*pp)->pNext;
+
+ pCache->nPage--;
+}
+
+/*
+** If there are currently more than nMaxPage pages allocated, try
+** to recycle pages to reduce the number allocated to nMaxPage.
+*/
+static void pcache1EnforceMaxPage(PGroup *pGroup){
+ assert( sqlite3_mutex_held(pGroup->mutex) );
+ while( pGroup->nCurrentPage>pGroup->nMaxPage && pGroup->pLruTail ){
+ PgHdr1 *p = pGroup->pLruTail;
+ assert( p->pCache->pGroup==pGroup );
+ assert( p->isPinned==0 );
+ pcache1PinPage(p);
+ pcache1RemoveFromHash(p);
+ pcache1FreePage(p);
+ }
+}
+
+/*
+** Discard all pages from cache pCache with a page number (key value)
+** greater than or equal to iLimit. Any pinned pages that meet this
+** criteria are unpinned before they are discarded.
+**
+** The PCache mutex must be held when this function is called.
+*/
+static void pcache1TruncateUnsafe(
+ PCache1 *pCache, /* The cache to truncate */
+ unsigned int iLimit /* Drop pages with this pgno or larger */
+){
+ TESTONLY( unsigned int nPage = 0; ) /* To assert pCache->nPage is correct */
+ unsigned int h;
+ assert( sqlite3_mutex_held(pCache->pGroup->mutex) );
+ for(h=0; hnHash; h++){
+ PgHdr1 **pp = &pCache->apHash[h];
+ PgHdr1 *pPage;
+ while( (pPage = *pp)!=0 ){
+ if( pPage->iKey>=iLimit ){
+ pCache->nPage--;
+ *pp = pPage->pNext;
+ if( !pPage->isPinned ) pcache1PinPage(pPage);
+ pcache1FreePage(pPage);
+ }else{
+ pp = &pPage->pNext;
+ TESTONLY( nPage++; )
+ }
+ }
+ }
+ assert( pCache->nPage==nPage );
+}
+
+/******************************************************************************/
+/******** sqlite3_pcache Methods **********************************************/
+
+/*
+** Implementation of the sqlite3_pcache.xInit method.
+*/
+static int pcache1Init(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ assert( pcache1.isInit==0 );
+ memset(&pcache1, 0, sizeof(pcache1));
+ if( sqlite3GlobalConfig.bCoreMutex ){
+ pcache1.grp.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU);
+ pcache1.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_PMEM);
+ }
+ pcache1.grp.mxPinned = 10;
+ pcache1.isInit = 1;
+ return SQLITE_OK;
+}
+
+/*
+** Implementation of the sqlite3_pcache.xShutdown method.
+** Note that the static mutex allocated in xInit does
+** not need to be freed.
+*/
+static void pcache1Shutdown(void *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ assert( pcache1.isInit!=0 );
+ memset(&pcache1, 0, sizeof(pcache1));
+}
+
+/*
+** Implementation of the sqlite3_pcache.xCreate method.
+**
+** Allocate a new cache.
+*/
+static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
+ PCache1 *pCache; /* The newly created page cache */
+ PGroup *pGroup; /* The group the new page cache will belong to */
+ int sz; /* Bytes of memory required to allocate the new cache */
+
+ /*
+ ** The separateCache variable is true if each PCache has its own private
+ ** PGroup. In other words, separateCache is true for mode (1) where no
+ ** mutexing is required.
+ **
+ ** * Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
+ **
+ ** * Always use a unified cache in single-threaded applications
+ **
+ ** * Otherwise (if multi-threaded and ENABLE_MEMORY_MANAGEMENT is off)
+ ** use separate caches (mode-1)
+ */
+#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
+ const int separateCache = 0;
+#else
+ int separateCache = sqlite3GlobalConfig.bCoreMutex>0;
+#endif
+
+ assert( (szPage & (szPage-1))==0 && szPage>=512 && szPage<=65536 );
+ assert( szExtra < 300 );
+
+ sz = sizeof(PCache1) + sizeof(PGroup)*separateCache;
+ pCache = (PCache1 *)sqlite3MallocZero(sz);
+ if( pCache ){
+ if( separateCache ){
+ pGroup = (PGroup*)&pCache[1];
+ pGroup->mxPinned = 10;
+ }else{
+ pGroup = &pcache1.grp;
+ }
+ pCache->pGroup = pGroup;
+ pCache->szPage = szPage;
+ pCache->szExtra = szExtra;
+ pCache->bPurgeable = (bPurgeable ? 1 : 0);
+ if( bPurgeable ){
+ pCache->nMin = 10;
+ pcache1EnterMutex(pGroup);
+ pGroup->nMinPage += pCache->nMin;
+ pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
+ pcache1LeaveMutex(pGroup);
+ }
+ }
+ return (sqlite3_pcache *)pCache;
+}
+
+/*
+** Implementation of the sqlite3_pcache.xCachesize method.
+**
+** Configure the cache_size limit for a cache.
+*/
+static void pcache1Cachesize(sqlite3_pcache *p, int nMax){
+ PCache1 *pCache = (PCache1 *)p;
+ if( pCache->bPurgeable ){
+ PGroup *pGroup = pCache->pGroup;
+ pcache1EnterMutex(pGroup);
+ pGroup->nMaxPage += (nMax - pCache->nMax);
+ pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
+ pCache->nMax = nMax;
+ pCache->n90pct = pCache->nMax*9/10;
+ pcache1EnforceMaxPage(pGroup);
+ pcache1LeaveMutex(pGroup);
+ }
+}
+
+/*
+** Implementation of the sqlite3_pcache.xShrink method.
+**
+** Free up as much memory as possible.
+*/
+static void pcache1Shrink(sqlite3_pcache *p){
+ PCache1 *pCache = (PCache1*)p;
+ if( pCache->bPurgeable ){
+ PGroup *pGroup = pCache->pGroup;
+ int savedMaxPage;
+ pcache1EnterMutex(pGroup);
+ savedMaxPage = pGroup->nMaxPage;
+ pGroup->nMaxPage = 0;
+ pcache1EnforceMaxPage(pGroup);
+ pGroup->nMaxPage = savedMaxPage;
+ pcache1LeaveMutex(pGroup);
+ }
+}
+
+/*
+** Implementation of the sqlite3_pcache.xPagecount method.
+*/
+static int pcache1Pagecount(sqlite3_pcache *p){
+ int n;
+ PCache1 *pCache = (PCache1*)p;
+ pcache1EnterMutex(pCache->pGroup);
+ n = pCache->nPage;
+ pcache1LeaveMutex(pCache->pGroup);
+ return n;
+}
+
+/*
+** Implementation of the sqlite3_pcache.xFetch method.
+**
+** Fetch a page by key value.
+**
+** Whether or not a new page may be allocated by this function depends on
+** the value of the createFlag argument. 0 means do not allocate a new
+** page. 1 means allocate a new page if space is easily available. 2
+** means to try really hard to allocate a new page.
+**
+** For a non-purgeable cache (a cache used as the storage for an in-memory
+** database) there is really no difference between createFlag 1 and 2. So
+** the calling function (pcache.c) will never have a createFlag of 1 on
+** a non-purgeable cache.
+**
+** There are three different approaches to obtaining space for a page,
+** depending on the value of parameter createFlag (which may be 0, 1 or 2).
+**
+** 1. Regardless of the value of createFlag, the cache is searched for a
+** copy of the requested page. If one is found, it is returned.
+**
+** 2. If createFlag==0 and the page is not already in the cache, NULL is
+** returned.
+**
+** 3. If createFlag is 1, and the page is not already in the cache, then
+** return NULL (do not allocate a new page) if any of the following
+** conditions are true:
+**
+** (a) the number of pages pinned by the cache is greater than
+** PCache1.nMax, or
+**
+** (b) the number of pages pinned by the cache is greater than
+** the sum of nMax for all purgeable caches, less the sum of
+** nMin for all other purgeable caches, or
+**
+** 4. If none of the first three conditions apply and the cache is marked
+** as purgeable, and if one of the following is true:
+**
+** (a) The number of pages allocated for the cache is already
+** PCache1.nMax, or
+**
+** (b) The number of pages allocated for all purgeable caches is
+** already equal to or greater than the sum of nMax for all
+** purgeable caches,
+**
+** (c) The system is under memory pressure and wants to avoid
+** unnecessary pages cache entry allocations
+**
+** then attempt to recycle a page from the LRU list. If it is the right
+** size, return the recycled buffer. Otherwise, free the buffer and
+** proceed to step 5.
+**
+** 5. Otherwise, allocate and return a new page buffer.
+*/
+static sqlite3_pcache_page *pcache1Fetch(
+ sqlite3_pcache *p,
+ unsigned int iKey,
+ int createFlag
+){
+ unsigned int nPinned;
+ PCache1 *pCache = (PCache1 *)p;
+ PGroup *pGroup;
+ PgHdr1 *pPage = 0;
+
+ assert( offsetof(PgHdr1,page)==0 );
+ assert( pCache->bPurgeable || createFlag!=1 );
+ assert( pCache->bPurgeable || pCache->nMin==0 );
+ assert( pCache->bPurgeable==0 || pCache->nMin==10 );
+ assert( pCache->nMin==0 || pCache->bPurgeable );
+ pcache1EnterMutex(pGroup = pCache->pGroup);
+
+ /* Step 1: Search the hash table for an existing entry. */
+ if( pCache->nHash>0 ){
+ unsigned int h = iKey % pCache->nHash;
+ for(pPage=pCache->apHash[h]; pPage&&pPage->iKey!=iKey; pPage=pPage->pNext);
+ }
+
+ /* Step 2: Abort if no existing page is found and createFlag is 0 */
+ if( pPage ){
+ if( !pPage->isPinned ) pcache1PinPage(pPage);
+ goto fetch_out;
+ }
+ if( createFlag==0 ){
+ goto fetch_out;
+ }
+
+ /* The pGroup local variable will normally be initialized by the
+ ** pcache1EnterMutex() macro above. But if SQLITE_MUTEX_OMIT is defined,
+ ** then pcache1EnterMutex() is a no-op, so we have to initialize the
+ ** local variable here. Delaying the initialization of pGroup is an
+ ** optimization: The common case is to exit the module before reaching
+ ** this point.
+ */
+#ifdef SQLITE_MUTEX_OMIT
+ pGroup = pCache->pGroup;
+#endif
+
+ /* Step 3: Abort if createFlag is 1 but the cache is nearly full */
+ assert( pCache->nPage >= pCache->nRecyclable );
+ nPinned = pCache->nPage - pCache->nRecyclable;
+ assert( pGroup->mxPinned == pGroup->nMaxPage + 10 - pGroup->nMinPage );
+ assert( pCache->n90pct == pCache->nMax*9/10 );
+ if( createFlag==1 && (
+ nPinned>=pGroup->mxPinned
+ || nPinned>=pCache->n90pct
+ || pcache1UnderMemoryPressure(pCache)
+ )){
+ goto fetch_out;
+ }
+
+ if( pCache->nPage>=pCache->nHash && pcache1ResizeHash(pCache) ){
+ goto fetch_out;
+ }
+ assert( pCache->nHash>0 && pCache->apHash );
+
+ /* Step 4. Try to recycle a page. */
+ if( pCache->bPurgeable && pGroup->pLruTail && (
+ (pCache->nPage+1>=pCache->nMax)
+ || pGroup->nCurrentPage>=pGroup->nMaxPage
+ || pcache1UnderMemoryPressure(pCache)
+ )){
+ PCache1 *pOther;
+ pPage = pGroup->pLruTail;
+ assert( pPage->isPinned==0 );
+ pcache1RemoveFromHash(pPage);
+ pcache1PinPage(pPage);
+ pOther = pPage->pCache;
+
+ /* We want to verify that szPage and szExtra are the same for pOther
+ ** and pCache. Assert that we can verify this by comparing sums. */
+ assert( (pCache->szPage & (pCache->szPage-1))==0 && pCache->szPage>=512 );
+ assert( pCache->szExtra<512 );
+ assert( (pOther->szPage & (pOther->szPage-1))==0 && pOther->szPage>=512 );
+ assert( pOther->szExtra<512 );
+
+ if( pOther->szPage+pOther->szExtra != pCache->szPage+pCache->szExtra ){
+ pcache1FreePage(pPage);
+ pPage = 0;
+ }else{
+ pGroup->nCurrentPage -= (pOther->bPurgeable - pCache->bPurgeable);
+ }
+ }
+
+ /* Step 5. If a usable page buffer has still not been found,
+ ** attempt to allocate a new one.
+ */
+ if( !pPage ){
+ if( createFlag==1 ) sqlite3BeginBenignMalloc();
+ pPage = pcache1AllocPage(pCache);
+ if( createFlag==1 ) sqlite3EndBenignMalloc();
+ }
+
+ if( pPage ){
+ unsigned int h = iKey % pCache->nHash;
+ pCache->nPage++;
+ pPage->iKey = iKey;
+ pPage->pNext = pCache->apHash[h];
+ pPage->pCache = pCache;
+ pPage->pLruPrev = 0;
+ pPage->pLruNext = 0;
+ pPage->isPinned = 1;
+ *(void **)pPage->page.pExtra = 0;
+ pCache->apHash[h] = pPage;
+ }
+
+fetch_out:
+ if( pPage && iKey>pCache->iMaxKey ){
+ pCache->iMaxKey = iKey;
+ }
+ pcache1LeaveMutex(pGroup);
+ return (sqlite3_pcache_page*)pPage;
+}
+
+
+/*
+** Implementation of the sqlite3_pcache.xUnpin method.
+**
+** Mark a page as unpinned (eligible for asynchronous recycling).
+*/
+static void pcache1Unpin(
+ sqlite3_pcache *p,
+ sqlite3_pcache_page *pPg,
+ int reuseUnlikely
+){
+ PCache1 *pCache = (PCache1 *)p;
+ PgHdr1 *pPage = (PgHdr1 *)pPg;
+ PGroup *pGroup = pCache->pGroup;
+
+ assert( pPage->pCache==pCache );
+ pcache1EnterMutex(pGroup);
+
+ /* It is an error to call this function if the page is already
+ ** part of the PGroup LRU list.
+ */
+ assert( pPage->pLruPrev==0 && pPage->pLruNext==0 );
+ assert( pGroup->pLruHead!=pPage && pGroup->pLruTail!=pPage );
+ assert( pPage->isPinned==1 );
+
+ if( reuseUnlikely || pGroup->nCurrentPage>pGroup->nMaxPage ){
+ pcache1RemoveFromHash(pPage);
+ pcache1FreePage(pPage);
+ }else{
+ /* Add the page to the PGroup LRU list. */
+ if( pGroup->pLruHead ){
+ pGroup->pLruHead->pLruPrev = pPage;
+ pPage->pLruNext = pGroup->pLruHead;
+ pGroup->pLruHead = pPage;
+ }else{
+ pGroup->pLruTail = pPage;
+ pGroup->pLruHead = pPage;
+ }
+ pCache->nRecyclable++;
+ pPage->isPinned = 0;
+ }
+
+ pcache1LeaveMutex(pCache->pGroup);
+}
+
+/*
+** Implementation of the sqlite3_pcache.xRekey method.
+*/
+static void pcache1Rekey(
+ sqlite3_pcache *p,
+ sqlite3_pcache_page *pPg,
+ unsigned int iOld,
+ unsigned int iNew
+){
+ PCache1 *pCache = (PCache1 *)p;
+ PgHdr1 *pPage = (PgHdr1 *)pPg;
+ PgHdr1 **pp;
+ unsigned int h;
+ assert( pPage->iKey==iOld );
+ assert( pPage->pCache==pCache );
+
+ pcache1EnterMutex(pCache->pGroup);
+
+ h = iOld%pCache->nHash;
+ pp = &pCache->apHash[h];
+ while( (*pp)!=pPage ){
+ pp = &(*pp)->pNext;
+ }
+ *pp = pPage->pNext;
+
+ h = iNew%pCache->nHash;
+ pPage->iKey = iNew;
+ pPage->pNext = pCache->apHash[h];
+ pCache->apHash[h] = pPage;
+ if( iNew>pCache->iMaxKey ){
+ pCache->iMaxKey = iNew;
+ }
+
+ pcache1LeaveMutex(pCache->pGroup);
+}
+
+/*
+** Implementation of the sqlite3_pcache.xTruncate method.
+**
+** Discard all unpinned pages in the cache with a page number equal to
+** or greater than parameter iLimit. Any pinned pages with a page number
+** equal to or greater than iLimit are implicitly unpinned.
+*/
+static void pcache1Truncate(sqlite3_pcache *p, unsigned int iLimit){
+ PCache1 *pCache = (PCache1 *)p;
+ pcache1EnterMutex(pCache->pGroup);
+ if( iLimit<=pCache->iMaxKey ){
+ pcache1TruncateUnsafe(pCache, iLimit);
+ pCache->iMaxKey = iLimit-1;
+ }
+ pcache1LeaveMutex(pCache->pGroup);
+}
+
+/*
+** Implementation of the sqlite3_pcache.xDestroy method.
+**
+** Destroy a cache allocated using pcache1Create().
+*/
+static void pcache1Destroy(sqlite3_pcache *p){
+ PCache1 *pCache = (PCache1 *)p;
+ PGroup *pGroup = pCache->pGroup;
+ assert( pCache->bPurgeable || (pCache->nMax==0 && pCache->nMin==0) );
+ pcache1EnterMutex(pGroup);
+ pcache1TruncateUnsafe(pCache, 0);
+ assert( pGroup->nMaxPage >= pCache->nMax );
+ pGroup->nMaxPage -= pCache->nMax;
+ assert( pGroup->nMinPage >= pCache->nMin );
+ pGroup->nMinPage -= pCache->nMin;
+ pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
+ pcache1EnforceMaxPage(pGroup);
+ pcache1LeaveMutex(pGroup);
+ sqlite3_free(pCache->apHash);
+ sqlite3_free(pCache);
+}
+
+/*
+** This function is called during initialization (sqlite3_initialize()) to
+** install the default pluggable cache module, assuming the user has not
+** already provided an alternative.
+*/
+SQLITE_PRIVATE void sqlite3PCacheSetDefault(void){
+ static const sqlite3_pcache_methods2 defaultMethods = {
+ 1, /* iVersion */
+ 0, /* pArg */
+ pcache1Init, /* xInit */
+ pcache1Shutdown, /* xShutdown */
+ pcache1Create, /* xCreate */
+ pcache1Cachesize, /* xCachesize */
+ pcache1Pagecount, /* xPagecount */
+ pcache1Fetch, /* xFetch */
+ pcache1Unpin, /* xUnpin */
+ pcache1Rekey, /* xRekey */
+ pcache1Truncate, /* xTruncate */
+ pcache1Destroy, /* xDestroy */
+ pcache1Shrink /* xShrink */
+ };
+ sqlite3_config(SQLITE_CONFIG_PCACHE2, &defaultMethods);
+}
+
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/*
+** This function is called to free superfluous dynamically allocated memory
+** held by the pager system. Memory in use by any SQLite pager allocated
+** by the current thread may be sqlite3_free()ed.
+**
+** nReq is the number of bytes of memory required. Once this much has
+** been released, the function returns. The return value is the total number
+** of bytes of memory released.
+*/
+SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int nReq){
+ int nFree = 0;
+ assert( sqlite3_mutex_notheld(pcache1.grp.mutex) );
+ assert( sqlite3_mutex_notheld(pcache1.mutex) );
+ if( pcache1.pStart==0 ){
+ PgHdr1 *p;
+ pcache1EnterMutex(&pcache1.grp);
+ while( (nReq<0 || nFreepage.pBuf);
+#ifdef SQLITE_PCACHE_SEPARATE_HEADER
+ nFree += sqlite3MemSize(p);
+#endif
+ assert( p->isPinned==0 );
+ pcache1PinPage(p);
+ pcache1RemoveFromHash(p);
+ pcache1FreePage(p);
+ }
+ pcache1LeaveMutex(&pcache1.grp);
+ }
+ return nFree;
+}
+#endif /* SQLITE_ENABLE_MEMORY_MANAGEMENT */
+
+#ifdef SQLITE_TEST
+/*
+** This function is used by test procedures to inspect the internal state
+** of the global cache.
+*/
+SQLITE_PRIVATE void sqlite3PcacheStats(
+ int *pnCurrent, /* OUT: Total number of pages cached */
+ int *pnMax, /* OUT: Global maximum cache size */
+ int *pnMin, /* OUT: Sum of PCache1.nMin for purgeable caches */
+ int *pnRecyclable /* OUT: Total number of pages available for recycling */
+){
+ PgHdr1 *p;
+ int nRecyclable = 0;
+ for(p=pcache1.grp.pLruHead; p; p=p->pLruNext){
+ assert( p->isPinned==0 );
+ nRecyclable++;
+ }
+ *pnCurrent = pcache1.grp.nCurrentPage;
+ *pnMax = (int)pcache1.grp.nMaxPage;
+ *pnMin = (int)pcache1.grp.nMinPage;
+ *pnRecyclable = nRecyclable;
+}
+#endif
+
+/************** End of pcache1.c *********************************************/
+/************** Begin file rowset.c ******************************************/
+/*
+** 2008 December 3
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This module implements an object we call a "RowSet".
+**
+** The RowSet object is a collection of rowids. Rowids
+** are inserted into the RowSet in an arbitrary order. Inserts
+** can be intermixed with tests to see if a given rowid has been
+** previously inserted into the RowSet.
+**
+** After all inserts are finished, it is possible to extract the
+** elements of the RowSet in sorted order. Once this extraction
+** process has started, no new elements may be inserted.
+**
+** Hence, the primitive operations for a RowSet are:
+**
+** CREATE
+** INSERT
+** TEST
+** SMALLEST
+** DESTROY
+**
+** The CREATE and DESTROY primitives are the constructor and destructor,
+** obviously. The INSERT primitive adds a new element to the RowSet.
+** TEST checks to see if an element is already in the RowSet. SMALLEST
+** extracts the least value from the RowSet.
+**
+** The INSERT primitive might allocate additional memory. Memory is
+** allocated in chunks so most INSERTs do no allocation. There is an
+** upper bound on the size of allocated memory. No memory is freed
+** until DESTROY.
+**
+** The TEST primitive includes a "batch" number. The TEST primitive
+** will only see elements that were inserted before the last change
+** in the batch number. In other words, if an INSERT occurs between
+** two TESTs where the TESTs have the same batch nubmer, then the
+** value added by the INSERT will not be visible to the second TEST.
+** The initial batch number is zero, so if the very first TEST contains
+** a non-zero batch number, it will see all prior INSERTs.
+**
+** No INSERTs may occurs after a SMALLEST. An assertion will fail if
+** that is attempted.
+**
+** The cost of an INSERT is roughly constant. (Sometime new memory
+** has to be allocated on an INSERT.) The cost of a TEST with a new
+** batch number is O(NlogN) where N is the number of elements in the RowSet.
+** The cost of a TEST using the same batch number is O(logN). The cost
+** of the first SMALLEST is O(NlogN). Second and subsequent SMALLEST
+** primitives are constant time. The cost of DESTROY is O(N).
+**
+** There is an added cost of O(N) when switching between TEST and
+** SMALLEST primitives.
+*/
+
+
+/*
+** Target size for allocation chunks.
+*/
+#define ROWSET_ALLOCATION_SIZE 1024
+
+/*
+** The number of rowset entries per allocation chunk.
+*/
+#define ROWSET_ENTRY_PER_CHUNK \
+ ((ROWSET_ALLOCATION_SIZE-8)/sizeof(struct RowSetEntry))
+
+/*
+** Each entry in a RowSet is an instance of the following object.
+**
+** This same object is reused to store a linked list of trees of RowSetEntry
+** objects. In that alternative use, pRight points to the next entry
+** in the list, pLeft points to the tree, and v is unused. The
+** RowSet.pForest value points to the head of this forest list.
+*/
+struct RowSetEntry {
+ i64 v; /* ROWID value for this entry */
+ struct RowSetEntry *pRight; /* Right subtree (larger entries) or list */
+ struct RowSetEntry *pLeft; /* Left subtree (smaller entries) */
+};
+
+/*
+** RowSetEntry objects are allocated in large chunks (instances of the
+** following structure) to reduce memory allocation overhead. The
+** chunks are kept on a linked list so that they can be deallocated
+** when the RowSet is destroyed.
+*/
+struct RowSetChunk {
+ struct RowSetChunk *pNextChunk; /* Next chunk on list of them all */
+ struct RowSetEntry aEntry[ROWSET_ENTRY_PER_CHUNK]; /* Allocated entries */
+};
+
+/*
+** A RowSet in an instance of the following structure.
+**
+** A typedef of this structure if found in sqliteInt.h.
+*/
+struct RowSet {
+ struct RowSetChunk *pChunk; /* List of all chunk allocations */
+ sqlite3 *db; /* The database connection */
+ struct RowSetEntry *pEntry; /* List of entries using pRight */
+ struct RowSetEntry *pLast; /* Last entry on the pEntry list */
+ struct RowSetEntry *pFresh; /* Source of new entry objects */
+ struct RowSetEntry *pForest; /* List of binary trees of entries */
+ u16 nFresh; /* Number of objects on pFresh */
+ u16 rsFlags; /* Various flags */
+ int iBatch; /* Current insert batch */
+};
+
+/*
+** Allowed values for RowSet.rsFlags
+*/
+#define ROWSET_SORTED 0x01 /* True if RowSet.pEntry is sorted */
+#define ROWSET_NEXT 0x02 /* True if sqlite3RowSetNext() has been called */
+
+/*
+** Turn bulk memory into a RowSet object. N bytes of memory
+** are available at pSpace. The db pointer is used as a memory context
+** for any subsequent allocations that need to occur.
+** Return a pointer to the new RowSet object.
+**
+** It must be the case that N is sufficient to make a Rowset. If not
+** an assertion fault occurs.
+**
+** If N is larger than the minimum, use the surplus as an initial
+** allocation of entries available to be filled.
+*/
+SQLITE_PRIVATE RowSet *sqlite3RowSetInit(sqlite3 *db, void *pSpace, unsigned int N){
+ RowSet *p;
+ assert( N >= ROUND8(sizeof(*p)) );
+ p = pSpace;
+ p->pChunk = 0;
+ p->db = db;
+ p->pEntry = 0;
+ p->pLast = 0;
+ p->pForest = 0;
+ p->pFresh = (struct RowSetEntry*)(ROUND8(sizeof(*p)) + (char*)p);
+ p->nFresh = (u16)((N - ROUND8(sizeof(*p)))/sizeof(struct RowSetEntry));
+ p->rsFlags = ROWSET_SORTED;
+ p->iBatch = 0;
+ return p;
+}
+
+/*
+** Deallocate all chunks from a RowSet. This frees all memory that
+** the RowSet has allocated over its lifetime. This routine is
+** the destructor for the RowSet.
+*/
+SQLITE_PRIVATE void sqlite3RowSetClear(RowSet *p){
+ struct RowSetChunk *pChunk, *pNextChunk;
+ for(pChunk=p->pChunk; pChunk; pChunk = pNextChunk){
+ pNextChunk = pChunk->pNextChunk;
+ sqlite3DbFree(p->db, pChunk);
+ }
+ p->pChunk = 0;
+ p->nFresh = 0;
+ p->pEntry = 0;
+ p->pLast = 0;
+ p->pForest = 0;
+ p->rsFlags = ROWSET_SORTED;
+}
+
+/*
+** Allocate a new RowSetEntry object that is associated with the
+** given RowSet. Return a pointer to the new and completely uninitialized
+** objected.
+**
+** In an OOM situation, the RowSet.db->mallocFailed flag is set and this
+** routine returns NULL.
+*/
+static struct RowSetEntry *rowSetEntryAlloc(RowSet *p){
+ assert( p!=0 );
+ if( p->nFresh==0 ){
+ struct RowSetChunk *pNew;
+ pNew = sqlite3DbMallocRaw(p->db, sizeof(*pNew));
+ if( pNew==0 ){
+ return 0;
+ }
+ pNew->pNextChunk = p->pChunk;
+ p->pChunk = pNew;
+ p->pFresh = pNew->aEntry;
+ p->nFresh = ROWSET_ENTRY_PER_CHUNK;
+ }
+ p->nFresh--;
+ return p->pFresh++;
+}
+
+/*
+** Insert a new value into a RowSet.
+**
+** The mallocFailed flag of the database connection is set if a
+** memory allocation fails.
+*/
+SQLITE_PRIVATE void sqlite3RowSetInsert(RowSet *p, i64 rowid){
+ struct RowSetEntry *pEntry; /* The new entry */
+ struct RowSetEntry *pLast; /* The last prior entry */
+
+ /* This routine is never called after sqlite3RowSetNext() */
+ assert( p!=0 && (p->rsFlags & ROWSET_NEXT)==0 );
+
+ pEntry = rowSetEntryAlloc(p);
+ if( pEntry==0 ) return;
+ pEntry->v = rowid;
+ pEntry->pRight = 0;
+ pLast = p->pLast;
+ if( pLast ){
+ if( (p->rsFlags & ROWSET_SORTED)!=0 && rowid<=pLast->v ){
+ p->rsFlags &= ~ROWSET_SORTED;
+ }
+ pLast->pRight = pEntry;
+ }else{
+ p->pEntry = pEntry;
+ }
+ p->pLast = pEntry;
+}
+
+/*
+** Merge two lists of RowSetEntry objects. Remove duplicates.
+**
+** The input lists are connected via pRight pointers and are
+** assumed to each already be in sorted order.
+*/
+static struct RowSetEntry *rowSetEntryMerge(
+ struct RowSetEntry *pA, /* First sorted list to be merged */
+ struct RowSetEntry *pB /* Second sorted list to be merged */
+){
+ struct RowSetEntry head;
+ struct RowSetEntry *pTail;
+
+ pTail = &head;
+ while( pA && pB ){
+ assert( pA->pRight==0 || pA->v<=pA->pRight->v );
+ assert( pB->pRight==0 || pB->v<=pB->pRight->v );
+ if( pA->vv ){
+ pTail->pRight = pA;
+ pA = pA->pRight;
+ pTail = pTail->pRight;
+ }else if( pB->vv ){
+ pTail->pRight = pB;
+ pB = pB->pRight;
+ pTail = pTail->pRight;
+ }else{
+ pA = pA->pRight;
+ }
+ }
+ if( pA ){
+ assert( pA->pRight==0 || pA->v<=pA->pRight->v );
+ pTail->pRight = pA;
+ }else{
+ assert( pB==0 || pB->pRight==0 || pB->v<=pB->pRight->v );
+ pTail->pRight = pB;
+ }
+ return head.pRight;
+}
+
+/*
+** Sort all elements on the list of RowSetEntry objects into order of
+** increasing v.
+*/
+static struct RowSetEntry *rowSetEntrySort(struct RowSetEntry *pIn){
+ unsigned int i;
+ struct RowSetEntry *pNext, *aBucket[40];
+
+ memset(aBucket, 0, sizeof(aBucket));
+ while( pIn ){
+ pNext = pIn->pRight;
+ pIn->pRight = 0;
+ for(i=0; aBucket[i]; i++){
+ pIn = rowSetEntryMerge(aBucket[i], pIn);
+ aBucket[i] = 0;
+ }
+ aBucket[i] = pIn;
+ pIn = pNext;
+ }
+ pIn = 0;
+ for(i=0; ipLeft ){
+ struct RowSetEntry *p;
+ rowSetTreeToList(pIn->pLeft, ppFirst, &p);
+ p->pRight = pIn;
+ }else{
+ *ppFirst = pIn;
+ }
+ if( pIn->pRight ){
+ rowSetTreeToList(pIn->pRight, &pIn->pRight, ppLast);
+ }else{
+ *ppLast = pIn;
+ }
+ assert( (*ppLast)->pRight==0 );
+}
+
+
+/*
+** Convert a sorted list of elements (connected by pRight) into a binary
+** tree with depth of iDepth. A depth of 1 means the tree contains a single
+** node taken from the head of *ppList. A depth of 2 means a tree with
+** three nodes. And so forth.
+**
+** Use as many entries from the input list as required and update the
+** *ppList to point to the unused elements of the list. If the input
+** list contains too few elements, then construct an incomplete tree
+** and leave *ppList set to NULL.
+**
+** Return a pointer to the root of the constructed binary tree.
+*/
+static struct RowSetEntry *rowSetNDeepTree(
+ struct RowSetEntry **ppList,
+ int iDepth
+){
+ struct RowSetEntry *p; /* Root of the new tree */
+ struct RowSetEntry *pLeft; /* Left subtree */
+ if( *ppList==0 ){
+ return 0;
+ }
+ if( iDepth==1 ){
+ p = *ppList;
+ *ppList = p->pRight;
+ p->pLeft = p->pRight = 0;
+ return p;
+ }
+ pLeft = rowSetNDeepTree(ppList, iDepth-1);
+ p = *ppList;
+ if( p==0 ){
+ return pLeft;
+ }
+ p->pLeft = pLeft;
+ *ppList = p->pRight;
+ p->pRight = rowSetNDeepTree(ppList, iDepth-1);
+ return p;
+}
+
+/*
+** Convert a sorted list of elements into a binary tree. Make the tree
+** as deep as it needs to be in order to contain the entire list.
+*/
+static struct RowSetEntry *rowSetListToTree(struct RowSetEntry *pList){
+ int iDepth; /* Depth of the tree so far */
+ struct RowSetEntry *p; /* Current tree root */
+ struct RowSetEntry *pLeft; /* Left subtree */
+
+ assert( pList!=0 );
+ p = pList;
+ pList = p->pRight;
+ p->pLeft = p->pRight = 0;
+ for(iDepth=1; pList; iDepth++){
+ pLeft = p;
+ p = pList;
+ pList = p->pRight;
+ p->pLeft = pLeft;
+ p->pRight = rowSetNDeepTree(&pList, iDepth);
+ }
+ return p;
+}
+
+/*
+** Take all the entries on p->pEntry and on the trees in p->pForest and
+** sort them all together into one big ordered list on p->pEntry.
+**
+** This routine should only be called once in the life of a RowSet.
+*/
+static void rowSetToList(RowSet *p){
+
+ /* This routine is called only once */
+ assert( p!=0 && (p->rsFlags & ROWSET_NEXT)==0 );
+
+ if( (p->rsFlags & ROWSET_SORTED)==0 ){
+ p->pEntry = rowSetEntrySort(p->pEntry);
+ }
+
+ /* While this module could theoretically support it, sqlite3RowSetNext()
+ ** is never called after sqlite3RowSetText() for the same RowSet. So
+ ** there is never a forest to deal with. Should this change, simply
+ ** remove the assert() and the #if 0. */
+ assert( p->pForest==0 );
+#if 0
+ while( p->pForest ){
+ struct RowSetEntry *pTree = p->pForest->pLeft;
+ if( pTree ){
+ struct RowSetEntry *pHead, *pTail;
+ rowSetTreeToList(pTree, &pHead, &pTail);
+ p->pEntry = rowSetEntryMerge(p->pEntry, pHead);
+ }
+ p->pForest = p->pForest->pRight;
+ }
+#endif
+ p->rsFlags |= ROWSET_NEXT; /* Verify this routine is never called again */
+}
+
+/*
+** Extract the smallest element from the RowSet.
+** Write the element into *pRowid. Return 1 on success. Return
+** 0 if the RowSet is already empty.
+**
+** After this routine has been called, the sqlite3RowSetInsert()
+** routine may not be called again.
+*/
+SQLITE_PRIVATE int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
+ assert( p!=0 );
+
+ /* Merge the forest into a single sorted list on first call */
+ if( (p->rsFlags & ROWSET_NEXT)==0 ) rowSetToList(p);
+
+ /* Return the next entry on the list */
+ if( p->pEntry ){
+ *pRowid = p->pEntry->v;
+ p->pEntry = p->pEntry->pRight;
+ if( p->pEntry==0 ){
+ sqlite3RowSetClear(p);
+ }
+ return 1;
+ }else{
+ return 0;
+ }
+}
+
+/*
+** Check to see if element iRowid was inserted into the rowset as
+** part of any insert batch prior to iBatch. Return 1 or 0.
+**
+** If this is the first test of a new batch and if there exist entires
+** on pRowSet->pEntry, then sort those entires into the forest at
+** pRowSet->pForest so that they can be tested.
+*/
+SQLITE_PRIVATE int sqlite3RowSetTest(RowSet *pRowSet, int iBatch, sqlite3_int64 iRowid){
+ struct RowSetEntry *p, *pTree;
+
+ /* This routine is never called after sqlite3RowSetNext() */
+ assert( pRowSet!=0 && (pRowSet->rsFlags & ROWSET_NEXT)==0 );
+
+ /* Sort entries into the forest on the first test of a new batch
+ */
+ if( iBatch!=pRowSet->iBatch ){
+ p = pRowSet->pEntry;
+ if( p ){
+ struct RowSetEntry **ppPrevTree = &pRowSet->pForest;
+ if( (pRowSet->rsFlags & ROWSET_SORTED)==0 ){
+ p = rowSetEntrySort(p);
+ }
+ for(pTree = pRowSet->pForest; pTree; pTree=pTree->pRight){
+ ppPrevTree = &pTree->pRight;
+ if( pTree->pLeft==0 ){
+ pTree->pLeft = rowSetListToTree(p);
+ break;
+ }else{
+ struct RowSetEntry *pAux, *pTail;
+ rowSetTreeToList(pTree->pLeft, &pAux, &pTail);
+ pTree->pLeft = 0;
+ p = rowSetEntryMerge(pAux, p);
+ }
+ }
+ if( pTree==0 ){
+ *ppPrevTree = pTree = rowSetEntryAlloc(pRowSet);
+ if( pTree ){
+ pTree->v = 0;
+ pTree->pRight = 0;
+ pTree->pLeft = rowSetListToTree(p);
+ }
+ }
+ pRowSet->pEntry = 0;
+ pRowSet->pLast = 0;
+ pRowSet->rsFlags |= ROWSET_SORTED;
+ }
+ pRowSet->iBatch = iBatch;
+ }
+
+ /* Test to see if the iRowid value appears anywhere in the forest.
+ ** Return 1 if it does and 0 if not.
+ */
+ for(pTree = pRowSet->pForest; pTree; pTree=pTree->pRight){
+ p = pTree->pLeft;
+ while( p ){
+ if( p->vpRight;
+ }else if( p->v>iRowid ){
+ p = p->pLeft;
+ }else{
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+
+/************** End of rowset.c **********************************************/
+/************** Begin file pager.c *******************************************/
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the implementation of the page cache subsystem or "pager".
+**
+** The pager is used to access a database disk file. It implements
+** atomic commit and rollback through the use of a journal file that
+** is separate from the database file. The pager also implements file
+** locking to prevent two processes from writing the same database
+** file simultaneously, or one process from reading the database while
+** another is writing.
+*/
+#ifndef SQLITE_OMIT_DISKIO
+/************** Include wal.h in the middle of pager.c ***********************/
+/************** Begin file wal.h *********************************************/
+/*
+** 2010 February 1
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface to the write-ahead logging
+** system. Refer to the comments below and the header comment attached to
+** the implementation of each function in log.c for further details.
+*/
+
+#ifndef _WAL_H_
+#define _WAL_H_
+
+
+/* Additional values that can be added to the sync_flags argument of
+** sqlite3WalFrames():
+*/
+#define WAL_SYNC_TRANSACTIONS 0x20 /* Sync at the end of each transaction */
+#define SQLITE_SYNC_MASK 0x13 /* Mask off the SQLITE_SYNC_* values */
+
+#ifdef SQLITE_OMIT_WAL
+# define sqlite3WalOpen(x,y,z) 0
+# define sqlite3WalLimit(x,y)
+# define sqlite3WalClose(w,x,y,z) 0
+# define sqlite3WalBeginReadTransaction(y,z) 0
+# define sqlite3WalEndReadTransaction(z)
+# define sqlite3WalDbsize(y) 0
+# define sqlite3WalBeginWriteTransaction(y) 0
+# define sqlite3WalEndWriteTransaction(x) 0
+# define sqlite3WalUndo(x,y,z) 0
+# define sqlite3WalSavepoint(y,z)
+# define sqlite3WalSavepointUndo(y,z) 0
+# define sqlite3WalFrames(u,v,w,x,y,z) 0
+# define sqlite3WalCheckpoint(r,s,t,u,v,w,x,y,z) 0
+# define sqlite3WalCallback(z) 0
+# define sqlite3WalExclusiveMode(y,z) 0
+# define sqlite3WalHeapMemory(z) 0
+# define sqlite3WalFramesize(z) 0
+# define sqlite3WalFindFrame(x,y,z) 0
+#else
+
+#define WAL_SAVEPOINT_NDATA 4
+
+/* Connection to a write-ahead log (WAL) file.
+** There is one object of this type for each pager.
+*/
+typedef struct Wal Wal;
+
+/* Open and close a connection to a write-ahead log. */
+SQLITE_PRIVATE int sqlite3WalOpen(sqlite3_vfs*, sqlite3_file*, const char *, int, i64, Wal**);
+SQLITE_PRIVATE int sqlite3WalClose(Wal *pWal, int sync_flags, int, u8 *);
+
+/* Set the limiting size of a WAL file. */
+SQLITE_PRIVATE void sqlite3WalLimit(Wal*, i64);
+
+/* Used by readers to open (lock) and close (unlock) a snapshot. A
+** snapshot is like a read-transaction. It is the state of the database
+** at an instant in time. sqlite3WalOpenSnapshot gets a read lock and
+** preserves the current state even if the other threads or processes
+** write to or checkpoint the WAL. sqlite3WalCloseSnapshot() closes the
+** transaction and releases the lock.
+*/
+SQLITE_PRIVATE int sqlite3WalBeginReadTransaction(Wal *pWal, int *);
+SQLITE_PRIVATE void sqlite3WalEndReadTransaction(Wal *pWal);
+
+/* Read a page from the write-ahead log, if it is present. */
+SQLITE_PRIVATE int sqlite3WalFindFrame(Wal *, Pgno, u32 *);
+SQLITE_PRIVATE int sqlite3WalReadFrame(Wal *, u32, int, u8 *);
+
+/* If the WAL is not empty, return the size of the database. */
+SQLITE_PRIVATE Pgno sqlite3WalDbsize(Wal *pWal);
+
+/* Obtain or release the WRITER lock. */
+SQLITE_PRIVATE int sqlite3WalBeginWriteTransaction(Wal *pWal);
+SQLITE_PRIVATE int sqlite3WalEndWriteTransaction(Wal *pWal);
+
+/* Undo any frames written (but not committed) to the log */
+SQLITE_PRIVATE int sqlite3WalUndo(Wal *pWal, int (*xUndo)(void *, Pgno), void *pUndoCtx);
+
+/* Return an integer that records the current (uncommitted) write
+** position in the WAL */
+SQLITE_PRIVATE void sqlite3WalSavepoint(Wal *pWal, u32 *aWalData);
+
+/* Move the write position of the WAL back to iFrame. Called in
+** response to a ROLLBACK TO command. */
+SQLITE_PRIVATE int sqlite3WalSavepointUndo(Wal *pWal, u32 *aWalData);
+
+/* Write a frame or frames to the log. */
+SQLITE_PRIVATE int sqlite3WalFrames(Wal *pWal, int, PgHdr *, Pgno, int, int);
+
+/* Copy pages from the log to the database file */
+SQLITE_PRIVATE int sqlite3WalCheckpoint(
+ Wal *pWal, /* Write-ahead log connection */
+ int eMode, /* One of PASSIVE, FULL and RESTART */
+ int (*xBusy)(void*), /* Function to call when busy */
+ void *pBusyArg, /* Context argument for xBusyHandler */
+ int sync_flags, /* Flags to sync db file with (or 0) */
+ int nBuf, /* Size of buffer nBuf */
+ u8 *zBuf, /* Temporary buffer to use */
+ int *pnLog, /* OUT: Number of frames in WAL */
+ int *pnCkpt /* OUT: Number of backfilled frames in WAL */
+);
+
+/* Return the value to pass to a sqlite3_wal_hook callback, the
+** number of frames in the WAL at the point of the last commit since
+** sqlite3WalCallback() was called. If no commits have occurred since
+** the last call, then return 0.
+*/
+SQLITE_PRIVATE int sqlite3WalCallback(Wal *pWal);
+
+/* Tell the wal layer that an EXCLUSIVE lock has been obtained (or released)
+** by the pager layer on the database file.
+*/
+SQLITE_PRIVATE int sqlite3WalExclusiveMode(Wal *pWal, int op);
+
+/* Return true if the argument is non-NULL and the WAL module is using
+** heap-memory for the wal-index. Otherwise, if the argument is NULL or the
+** WAL module is using shared-memory, return false.
+*/
+SQLITE_PRIVATE int sqlite3WalHeapMemory(Wal *pWal);
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+/* If the WAL file is not empty, return the number of bytes of content
+** stored in each frame (i.e. the db page-size when the WAL was created).
+*/
+SQLITE_PRIVATE int sqlite3WalFramesize(Wal *pWal);
+#endif
+
+#endif /* ifndef SQLITE_OMIT_WAL */
+#endif /* _WAL_H_ */
+
+/************** End of wal.h *************************************************/
+/************** Continuing where we left off in pager.c **********************/
+
+
+/******************* NOTES ON THE DESIGN OF THE PAGER ************************
+**
+** This comment block describes invariants that hold when using a rollback
+** journal. These invariants do not apply for journal_mode=WAL,
+** journal_mode=MEMORY, or journal_mode=OFF.
+**
+** Within this comment block, a page is deemed to have been synced
+** automatically as soon as it is written when PRAGMA synchronous=OFF.
+** Otherwise, the page is not synced until the xSync method of the VFS
+** is called successfully on the file containing the page.
+**
+** Definition: A page of the database file is said to be "overwriteable" if
+** one or more of the following are true about the page:
+**
+** (a) The original content of the page as it was at the beginning of
+** the transaction has been written into the rollback journal and
+** synced.
+**
+** (b) The page was a freelist leaf page at the start of the transaction.
+**
+** (c) The page number is greater than the largest page that existed in
+** the database file at the start of the transaction.
+**
+** (1) A page of the database file is never overwritten unless one of the
+** following are true:
+**
+** (a) The page and all other pages on the same sector are overwriteable.
+**
+** (b) The atomic page write optimization is enabled, and the entire
+** transaction other than the update of the transaction sequence
+** number consists of a single page change.
+**
+** (2) The content of a page written into the rollback journal exactly matches
+** both the content in the database when the rollback journal was written
+** and the content in the database at the beginning of the current
+** transaction.
+**
+** (3) Writes to the database file are an integer multiple of the page size
+** in length and are aligned on a page boundary.
+**
+** (4) Reads from the database file are either aligned on a page boundary and
+** an integer multiple of the page size in length or are taken from the
+** first 100 bytes of the database file.
+**
+** (5) All writes to the database file are synced prior to the rollback journal
+** being deleted, truncated, or zeroed.
+**
+** (6) If a master journal file is used, then all writes to the database file
+** are synced prior to the master journal being deleted.
+**
+** Definition: Two databases (or the same database at two points it time)
+** are said to be "logically equivalent" if they give the same answer to
+** all queries. Note in particular the content of freelist leaf
+** pages can be changed arbitarily without effecting the logical equivalence
+** of the database.
+**
+** (7) At any time, if any subset, including the empty set and the total set,
+** of the unsynced changes to a rollback journal are removed and the
+** journal is rolled back, the resulting database file will be logical
+** equivalent to the database file at the beginning of the transaction.
+**
+** (8) When a transaction is rolled back, the xTruncate method of the VFS
+** is called to restore the database file to the same size it was at
+** the beginning of the transaction. (In some VFSes, the xTruncate
+** method is a no-op, but that does not change the fact the SQLite will
+** invoke it.)
+**
+** (9) Whenever the database file is modified, at least one bit in the range
+** of bytes from 24 through 39 inclusive will be changed prior to releasing
+** the EXCLUSIVE lock, thus signaling other connections on the same
+** database to flush their caches.
+**
+** (10) The pattern of bits in bytes 24 through 39 shall not repeat in less
+** than one billion transactions.
+**
+** (11) A database file is well-formed at the beginning and at the conclusion
+** of every transaction.
+**
+** (12) An EXCLUSIVE lock is held on the database file when writing to
+** the database file.
+**
+** (13) A SHARED lock is held on the database file while reading any
+** content out of the database file.
+**
+******************************************************************************/
+
+/*
+** Macros for troubleshooting. Normally turned off
+*/
+#if 0
+int sqlite3PagerTrace=1; /* True to enable tracing */
+#define sqlite3DebugPrintf printf
+#define PAGERTRACE(X) if( sqlite3PagerTrace ){ sqlite3DebugPrintf X; }
+#else
+#define PAGERTRACE(X)
+#endif
+
+/*
+** The following two macros are used within the PAGERTRACE() macros above
+** to print out file-descriptors.
+**
+** PAGERID() takes a pointer to a Pager struct as its argument. The
+** associated file-descriptor is returned. FILEHANDLEID() takes an sqlite3_file
+** struct as its argument.
+*/
+#define PAGERID(p) ((int)(p->fd))
+#define FILEHANDLEID(fd) ((int)fd)
+
+/*
+** The Pager.eState variable stores the current 'state' of a pager. A
+** pager may be in any one of the seven states shown in the following
+** state diagram.
+**
+** OPEN <------+------+
+** | | |
+** V | |
+** +---------> READER-------+ |
+** | | |
+** | V |
+** |<-------WRITER_LOCKED------> ERROR
+** | | ^
+** | V |
+** |<------WRITER_CACHEMOD-------->|
+** | | |
+** | V |
+** |<-------WRITER_DBMOD---------->|
+** | | |
+** | V |
+** +<------WRITER_FINISHED-------->+
+**
+**
+** List of state transitions and the C [function] that performs each:
+**
+** OPEN -> READER [sqlite3PagerSharedLock]
+** READER -> OPEN [pager_unlock]
+**
+** READER -> WRITER_LOCKED [sqlite3PagerBegin]
+** WRITER_LOCKED -> WRITER_CACHEMOD [pager_open_journal]
+** WRITER_CACHEMOD -> WRITER_DBMOD [syncJournal]
+** WRITER_DBMOD -> WRITER_FINISHED [sqlite3PagerCommitPhaseOne]
+** WRITER_*** -> READER [pager_end_transaction]
+**
+** WRITER_*** -> ERROR [pager_error]
+** ERROR -> OPEN [pager_unlock]
+**
+**
+** OPEN:
+**
+** The pager starts up in this state. Nothing is guaranteed in this
+** state - the file may or may not be locked and the database size is
+** unknown. The database may not be read or written.
+**
+** * No read or write transaction is active.
+** * Any lock, or no lock at all, may be held on the database file.
+** * The dbSize, dbOrigSize and dbFileSize variables may not be trusted.
+**
+** READER:
+**
+** In this state all the requirements for reading the database in
+** rollback (non-WAL) mode are met. Unless the pager is (or recently
+** was) in exclusive-locking mode, a user-level read transaction is
+** open. The database size is known in this state.
+**
+** A connection running with locking_mode=normal enters this state when
+** it opens a read-transaction on the database and returns to state
+** OPEN after the read-transaction is completed. However a connection
+** running in locking_mode=exclusive (including temp databases) remains in
+** this state even after the read-transaction is closed. The only way
+** a locking_mode=exclusive connection can transition from READER to OPEN
+** is via the ERROR state (see below).
+**
+** * A read transaction may be active (but a write-transaction cannot).
+** * A SHARED or greater lock is held on the database file.
+** * The dbSize variable may be trusted (even if a user-level read
+** transaction is not active). The dbOrigSize and dbFileSize variables
+** may not be trusted at this point.
+** * If the database is a WAL database, then the WAL connection is open.
+** * Even if a read-transaction is not open, it is guaranteed that
+** there is no hot-journal in the file-system.
+**
+** WRITER_LOCKED:
+**
+** The pager moves to this state from READER when a write-transaction
+** is first opened on the database. In WRITER_LOCKED state, all locks
+** required to start a write-transaction are held, but no actual
+** modifications to the cache or database have taken place.
+**
+** In rollback mode, a RESERVED or (if the transaction was opened with
+** BEGIN EXCLUSIVE) EXCLUSIVE lock is obtained on the database file when
+** moving to this state, but the journal file is not written to or opened
+** to in this state. If the transaction is committed or rolled back while
+** in WRITER_LOCKED state, all that is required is to unlock the database
+** file.
+**
+** IN WAL mode, WalBeginWriteTransaction() is called to lock the log file.
+** If the connection is running with locking_mode=exclusive, an attempt
+** is made to obtain an EXCLUSIVE lock on the database file.
+**
+** * A write transaction is active.
+** * If the connection is open in rollback-mode, a RESERVED or greater
+** lock is held on the database file.
+** * If the connection is open in WAL-mode, a WAL write transaction
+** is open (i.e. sqlite3WalBeginWriteTransaction() has been successfully
+** called).
+** * The dbSize, dbOrigSize and dbFileSize variables are all valid.
+** * The contents of the pager cache have not been modified.
+** * The journal file may or may not be open.
+** * Nothing (not even the first header) has been written to the journal.
+**
+** WRITER_CACHEMOD:
+**
+** A pager moves from WRITER_LOCKED state to this state when a page is
+** first modified by the upper layer. In rollback mode the journal file
+** is opened (if it is not already open) and a header written to the
+** start of it. The database file on disk has not been modified.
+**
+** * A write transaction is active.
+** * A RESERVED or greater lock is held on the database file.
+** * The journal file is open and the first header has been written
+** to it, but the header has not been synced to disk.
+** * The contents of the page cache have been modified.
+**
+** WRITER_DBMOD:
+**
+** The pager transitions from WRITER_CACHEMOD into WRITER_DBMOD state
+** when it modifies the contents of the database file. WAL connections
+** never enter this state (since they do not modify the database file,
+** just the log file).
+**
+** * A write transaction is active.
+** * An EXCLUSIVE or greater lock is held on the database file.
+** * The journal file is open and the first header has been written
+** and synced to disk.
+** * The contents of the page cache have been modified (and possibly
+** written to disk).
+**
+** WRITER_FINISHED:
+**
+** It is not possible for a WAL connection to enter this state.
+**
+** A rollback-mode pager changes to WRITER_FINISHED state from WRITER_DBMOD
+** state after the entire transaction has been successfully written into the
+** database file. In this state the transaction may be committed simply
+** by finalizing the journal file. Once in WRITER_FINISHED state, it is
+** not possible to modify the database further. At this point, the upper
+** layer must either commit or rollback the transaction.
+**
+** * A write transaction is active.
+** * An EXCLUSIVE or greater lock is held on the database file.
+** * All writing and syncing of journal and database data has finished.
+** If no error occurred, all that remains is to finalize the journal to
+** commit the transaction. If an error did occur, the caller will need
+** to rollback the transaction.
+**
+** ERROR:
+**
+** The ERROR state is entered when an IO or disk-full error (including
+** SQLITE_IOERR_NOMEM) occurs at a point in the code that makes it
+** difficult to be sure that the in-memory pager state (cache contents,
+** db size etc.) are consistent with the contents of the file-system.
+**
+** Temporary pager files may enter the ERROR state, but in-memory pagers
+** cannot.
+**
+** For example, if an IO error occurs while performing a rollback,
+** the contents of the page-cache may be left in an inconsistent state.
+** At this point it would be dangerous to change back to READER state
+** (as usually happens after a rollback). Any subsequent readers might
+** report database corruption (due to the inconsistent cache), and if
+** they upgrade to writers, they may inadvertently corrupt the database
+** file. To avoid this hazard, the pager switches into the ERROR state
+** instead of READER following such an error.
+**
+** Once it has entered the ERROR state, any attempt to use the pager
+** to read or write data returns an error. Eventually, once all
+** outstanding transactions have been abandoned, the pager is able to
+** transition back to OPEN state, discarding the contents of the
+** page-cache and any other in-memory state at the same time. Everything
+** is reloaded from disk (and, if necessary, hot-journal rollback peformed)
+** when a read-transaction is next opened on the pager (transitioning
+** the pager into READER state). At that point the system has recovered
+** from the error.
+**
+** Specifically, the pager jumps into the ERROR state if:
+**
+** 1. An error occurs while attempting a rollback. This happens in
+** function sqlite3PagerRollback().
+**
+** 2. An error occurs while attempting to finalize a journal file
+** following a commit in function sqlite3PagerCommitPhaseTwo().
+**
+** 3. An error occurs while attempting to write to the journal or
+** database file in function pagerStress() in order to free up
+** memory.
+**
+** In other cases, the error is returned to the b-tree layer. The b-tree
+** layer then attempts a rollback operation. If the error condition
+** persists, the pager enters the ERROR state via condition (1) above.
+**
+** Condition (3) is necessary because it can be triggered by a read-only
+** statement executed within a transaction. In this case, if the error
+** code were simply returned to the user, the b-tree layer would not
+** automatically attempt a rollback, as it assumes that an error in a
+** read-only statement cannot leave the pager in an internally inconsistent
+** state.
+**
+** * The Pager.errCode variable is set to something other than SQLITE_OK.
+** * There are one or more outstanding references to pages (after the
+** last reference is dropped the pager should move back to OPEN state).
+** * The pager is not an in-memory pager.
+**
+**
+** Notes:
+**
+** * A pager is never in WRITER_DBMOD or WRITER_FINISHED state if the
+** connection is open in WAL mode. A WAL connection is always in one
+** of the first four states.
+**
+** * Normally, a connection open in exclusive mode is never in PAGER_OPEN
+** state. There are two exceptions: immediately after exclusive-mode has
+** been turned on (and before any read or write transactions are
+** executed), and when the pager is leaving the "error state".
+**
+** * See also: assert_pager_state().
+*/
+#define PAGER_OPEN 0
+#define PAGER_READER 1
+#define PAGER_WRITER_LOCKED 2
+#define PAGER_WRITER_CACHEMOD 3
+#define PAGER_WRITER_DBMOD 4
+#define PAGER_WRITER_FINISHED 5
+#define PAGER_ERROR 6
+
+/*
+** The Pager.eLock variable is almost always set to one of the
+** following locking-states, according to the lock currently held on
+** the database file: NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
+** This variable is kept up to date as locks are taken and released by
+** the pagerLockDb() and pagerUnlockDb() wrappers.
+**
+** If the VFS xLock() or xUnlock() returns an error other than SQLITE_BUSY
+** (i.e. one of the SQLITE_IOERR subtypes), it is not clear whether or not
+** the operation was successful. In these circumstances pagerLockDb() and
+** pagerUnlockDb() take a conservative approach - eLock is always updated
+** when unlocking the file, and only updated when locking the file if the
+** VFS call is successful. This way, the Pager.eLock variable may be set
+** to a less exclusive (lower) value than the lock that is actually held
+** at the system level, but it is never set to a more exclusive value.
+**
+** This is usually safe. If an xUnlock fails or appears to fail, there may
+** be a few redundant xLock() calls or a lock may be held for longer than
+** required, but nothing really goes wrong.
+**
+** The exception is when the database file is unlocked as the pager moves
+** from ERROR to OPEN state. At this point there may be a hot-journal file
+** in the file-system that needs to be rolled back (as part of a OPEN->SHARED
+** transition, by the same pager or any other). If the call to xUnlock()
+** fails at this point and the pager is left holding an EXCLUSIVE lock, this
+** can confuse the call to xCheckReservedLock() call made later as part
+** of hot-journal detection.
+**
+** xCheckReservedLock() is defined as returning true "if there is a RESERVED
+** lock held by this process or any others". So xCheckReservedLock may
+** return true because the caller itself is holding an EXCLUSIVE lock (but
+** doesn't know it because of a previous error in xUnlock). If this happens
+** a hot-journal may be mistaken for a journal being created by an active
+** transaction in another process, causing SQLite to read from the database
+** without rolling it back.
+**
+** To work around this, if a call to xUnlock() fails when unlocking the
+** database in the ERROR state, Pager.eLock is set to UNKNOWN_LOCK. It
+** is only changed back to a real locking state after a successful call
+** to xLock(EXCLUSIVE). Also, the code to do the OPEN->SHARED state transition
+** omits the check for a hot-journal if Pager.eLock is set to UNKNOWN_LOCK
+** lock. Instead, it assumes a hot-journal exists and obtains an EXCLUSIVE
+** lock on the database file before attempting to roll it back. See function
+** PagerSharedLock() for more detail.
+**
+** Pager.eLock may only be set to UNKNOWN_LOCK when the pager is in
+** PAGER_OPEN state.
+*/
+#define UNKNOWN_LOCK (EXCLUSIVE_LOCK+1)
+
+/*
+** A macro used for invoking the codec if there is one
+*/
+#ifdef SQLITE_HAS_CODEC
+# define CODEC1(P,D,N,X,E) \
+ if( P->xCodec && P->xCodec(P->pCodec,D,N,X)==0 ){ E; }
+# define CODEC2(P,D,N,X,E,O) \
+ if( P->xCodec==0 ){ O=(char*)D; }else \
+ if( (O=(char*)(P->xCodec(P->pCodec,D,N,X)))==0 ){ E; }
+#else
+# define CODEC1(P,D,N,X,E) /* NO-OP */
+# define CODEC2(P,D,N,X,E,O) O=(char*)D
+#endif
+
+/*
+** The maximum allowed sector size. 64KiB. If the xSectorsize() method
+** returns a value larger than this, then MAX_SECTOR_SIZE is used instead.
+** This could conceivably cause corruption following a power failure on
+** such a system. This is currently an undocumented limit.
+*/
+#define MAX_SECTOR_SIZE 0x10000
+
+/*
+** An instance of the following structure is allocated for each active
+** savepoint and statement transaction in the system. All such structures
+** are stored in the Pager.aSavepoint[] array, which is allocated and
+** resized using sqlite3Realloc().
+**
+** When a savepoint is created, the PagerSavepoint.iHdrOffset field is
+** set to 0. If a journal-header is written into the main journal while
+** the savepoint is active, then iHdrOffset is set to the byte offset
+** immediately following the last journal record written into the main
+** journal before the journal-header. This is required during savepoint
+** rollback (see pagerPlaybackSavepoint()).
+*/
+typedef struct PagerSavepoint PagerSavepoint;
+struct PagerSavepoint {
+ i64 iOffset; /* Starting offset in main journal */
+ i64 iHdrOffset; /* See above */
+ Bitvec *pInSavepoint; /* Set of pages in this savepoint */
+ Pgno nOrig; /* Original number of pages in file */
+ Pgno iSubRec; /* Index of first record in sub-journal */
+#ifndef SQLITE_OMIT_WAL
+ u32 aWalData[WAL_SAVEPOINT_NDATA]; /* WAL savepoint context */
+#endif
+};
+
+/*
+** Bits of the Pager.doNotSpill flag. See further description below.
+*/
+#define SPILLFLAG_OFF 0x01 /* Never spill cache. Set via pragma */
+#define SPILLFLAG_ROLLBACK 0x02 /* Current rolling back, so do not spill */
+#define SPILLFLAG_NOSYNC 0x04 /* Spill is ok, but do not sync */
+
+/*
+** A open page cache is an instance of struct Pager. A description of
+** some of the more important member variables follows:
+**
+** eState
+**
+** The current 'state' of the pager object. See the comment and state
+** diagram above for a description of the pager state.
+**
+** eLock
+**
+** For a real on-disk database, the current lock held on the database file -
+** NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
+**
+** For a temporary or in-memory database (neither of which require any
+** locks), this variable is always set to EXCLUSIVE_LOCK. Since such
+** databases always have Pager.exclusiveMode==1, this tricks the pager
+** logic into thinking that it already has all the locks it will ever
+** need (and no reason to release them).
+**
+** In some (obscure) circumstances, this variable may also be set to
+** UNKNOWN_LOCK. See the comment above the #define of UNKNOWN_LOCK for
+** details.
+**
+** changeCountDone
+**
+** This boolean variable is used to make sure that the change-counter
+** (the 4-byte header field at byte offset 24 of the database file) is
+** not updated more often than necessary.
+**
+** It is set to true when the change-counter field is updated, which
+** can only happen if an exclusive lock is held on the database file.
+** It is cleared (set to false) whenever an exclusive lock is
+** relinquished on the database file. Each time a transaction is committed,
+** The changeCountDone flag is inspected. If it is true, the work of
+** updating the change-counter is omitted for the current transaction.
+**
+** This mechanism means that when running in exclusive mode, a connection
+** need only update the change-counter once, for the first transaction
+** committed.
+**
+** setMaster
+**
+** When PagerCommitPhaseOne() is called to commit a transaction, it may
+** (or may not) specify a master-journal name to be written into the
+** journal file before it is synced to disk.
+**
+** Whether or not a journal file contains a master-journal pointer affects
+** the way in which the journal file is finalized after the transaction is
+** committed or rolled back when running in "journal_mode=PERSIST" mode.
+** If a journal file does not contain a master-journal pointer, it is
+** finalized by overwriting the first journal header with zeroes. If
+** it does contain a master-journal pointer the journal file is finalized
+** by truncating it to zero bytes, just as if the connection were
+** running in "journal_mode=truncate" mode.
+**
+** Journal files that contain master journal pointers cannot be finalized
+** simply by overwriting the first journal-header with zeroes, as the
+** master journal pointer could interfere with hot-journal rollback of any
+** subsequently interrupted transaction that reuses the journal file.
+**
+** The flag is cleared as soon as the journal file is finalized (either
+** by PagerCommitPhaseTwo or PagerRollback). If an IO error prevents the
+** journal file from being successfully finalized, the setMaster flag
+** is cleared anyway (and the pager will move to ERROR state).
+**
+** doNotSpill
+**
+** This variables control the behavior of cache-spills (calls made by
+** the pcache module to the pagerStress() routine to write cached data
+** to the file-system in order to free up memory).
+**
+** When bits SPILLFLAG_OFF or SPILLFLAG_ROLLBACK of doNotSpill are set,
+** writing to the database from pagerStress() is disabled altogether.
+** The SPILLFLAG_ROLLBACK case is done in a very obscure case that
+** comes up during savepoint rollback that requires the pcache module
+** to allocate a new page to prevent the journal file from being written
+** while it is being traversed by code in pager_playback(). The SPILLFLAG_OFF
+** case is a user preference.
+**
+** If the SPILLFLAG_NOSYNC bit is set, writing to the database from pagerStress()
+** is permitted, but syncing the journal file is not. This flag is set
+** by sqlite3PagerWrite() when the file-system sector-size is larger than
+** the database page-size in order to prevent a journal sync from happening
+** in between the journalling of two pages on the same sector.
+**
+** subjInMemory
+**
+** This is a boolean variable. If true, then any required sub-journal
+** is opened as an in-memory journal file. If false, then in-memory
+** sub-journals are only used for in-memory pager files.
+**
+** This variable is updated by the upper layer each time a new
+** write-transaction is opened.
+**
+** dbSize, dbOrigSize, dbFileSize
+**
+** Variable dbSize is set to the number of pages in the database file.
+** It is valid in PAGER_READER and higher states (all states except for
+** OPEN and ERROR).
+**
+** dbSize is set based on the size of the database file, which may be
+** larger than the size of the database (the value stored at offset
+** 28 of the database header by the btree). If the size of the file
+** is not an integer multiple of the page-size, the value stored in
+** dbSize is rounded down (i.e. a 5KB file with 2K page-size has dbSize==2).
+** Except, any file that is greater than 0 bytes in size is considered
+** to have at least one page. (i.e. a 1KB file with 2K page-size leads
+** to dbSize==1).
+**
+** During a write-transaction, if pages with page-numbers greater than
+** dbSize are modified in the cache, dbSize is updated accordingly.
+** Similarly, if the database is truncated using PagerTruncateImage(),
+** dbSize is updated.
+**
+** Variables dbOrigSize and dbFileSize are valid in states
+** PAGER_WRITER_LOCKED and higher. dbOrigSize is a copy of the dbSize
+** variable at the start of the transaction. It is used during rollback,
+** and to determine whether or not pages need to be journalled before
+** being modified.
+**
+** Throughout a write-transaction, dbFileSize contains the size of
+** the file on disk in pages. It is set to a copy of dbSize when the
+** write-transaction is first opened, and updated when VFS calls are made
+** to write or truncate the database file on disk.
+**
+** The only reason the dbFileSize variable is required is to suppress
+** unnecessary calls to xTruncate() after committing a transaction. If,
+** when a transaction is committed, the dbFileSize variable indicates
+** that the database file is larger than the database image (Pager.dbSize),
+** pager_truncate() is called. The pager_truncate() call uses xFilesize()
+** to measure the database file on disk, and then truncates it if required.
+** dbFileSize is not used when rolling back a transaction. In this case
+** pager_truncate() is called unconditionally (which means there may be
+** a call to xFilesize() that is not strictly required). In either case,
+** pager_truncate() may cause the file to become smaller or larger.
+**
+** dbHintSize
+**
+** The dbHintSize variable is used to limit the number of calls made to
+** the VFS xFileControl(FCNTL_SIZE_HINT) method.
+**
+** dbHintSize is set to a copy of the dbSize variable when a
+** write-transaction is opened (at the same time as dbFileSize and
+** dbOrigSize). If the xFileControl(FCNTL_SIZE_HINT) method is called,
+** dbHintSize is increased to the number of pages that correspond to the
+** size-hint passed to the method call. See pager_write_pagelist() for
+** details.
+**
+** errCode
+**
+** The Pager.errCode variable is only ever used in PAGER_ERROR state. It
+** is set to zero in all other states. In PAGER_ERROR state, Pager.errCode
+** is always set to SQLITE_FULL, SQLITE_IOERR or one of the SQLITE_IOERR_XXX
+** sub-codes.
+*/
+struct Pager {
+ sqlite3_vfs *pVfs; /* OS functions to use for IO */
+ u8 exclusiveMode; /* Boolean. True if locking_mode==EXCLUSIVE */
+ u8 journalMode; /* One of the PAGER_JOURNALMODE_* values */
+ u8 useJournal; /* Use a rollback journal on this file */
+ u8 noSync; /* Do not sync the journal if true */
+ u8 fullSync; /* Do extra syncs of the journal for robustness */
+ u8 ckptSyncFlags; /* SYNC_NORMAL or SYNC_FULL for checkpoint */
+ u8 walSyncFlags; /* SYNC_NORMAL or SYNC_FULL for wal writes */
+ u8 syncFlags; /* SYNC_NORMAL or SYNC_FULL otherwise */
+ u8 tempFile; /* zFilename is a temporary or immutable file */
+ u8 noLock; /* Do not lock (except in WAL mode) */
+ u8 readOnly; /* True for a read-only database */
+ u8 memDb; /* True to inhibit all file I/O */
+
+ /**************************************************************************
+ ** The following block contains those class members that change during
+ ** routine opertion. Class members not in this block are either fixed
+ ** when the pager is first created or else only change when there is a
+ ** significant mode change (such as changing the page_size, locking_mode,
+ ** or the journal_mode). From another view, these class members describe
+ ** the "state" of the pager, while other class members describe the
+ ** "configuration" of the pager.
+ */
+ u8 eState; /* Pager state (OPEN, READER, WRITER_LOCKED..) */
+ u8 eLock; /* Current lock held on database file */
+ u8 changeCountDone; /* Set after incrementing the change-counter */
+ u8 setMaster; /* True if a m-j name has been written to jrnl */
+ u8 doNotSpill; /* Do not spill the cache when non-zero */
+ u8 subjInMemory; /* True to use in-memory sub-journals */
+ Pgno dbSize; /* Number of pages in the database */
+ Pgno dbOrigSize; /* dbSize before the current transaction */
+ Pgno dbFileSize; /* Number of pages in the database file */
+ Pgno dbHintSize; /* Value passed to FCNTL_SIZE_HINT call */
+ int errCode; /* One of several kinds of errors */
+ int nRec; /* Pages journalled since last j-header written */
+ u32 cksumInit; /* Quasi-random value added to every checksum */
+ u32 nSubRec; /* Number of records written to sub-journal */
+ Bitvec *pInJournal; /* One bit for each page in the database file */
+ sqlite3_file *fd; /* File descriptor for database */
+ sqlite3_file *jfd; /* File descriptor for main journal */
+ sqlite3_file *sjfd; /* File descriptor for sub-journal */
+ i64 journalOff; /* Current write offset in the journal file */
+ i64 journalHdr; /* Byte offset to previous journal header */
+ sqlite3_backup *pBackup; /* Pointer to list of ongoing backup processes */
+ PagerSavepoint *aSavepoint; /* Array of active savepoints */
+ int nSavepoint; /* Number of elements in aSavepoint[] */
+ char dbFileVers[16]; /* Changes whenever database file changes */
+
+ u8 bUseFetch; /* True to use xFetch() */
+ int nMmapOut; /* Number of mmap pages currently outstanding */
+ sqlite3_int64 szMmap; /* Desired maximum mmap size */
+ PgHdr *pMmapFreelist; /* List of free mmap page headers (pDirty) */
+ /*
+ ** End of the routinely-changing class members
+ ***************************************************************************/
+
+ u16 nExtra; /* Add this many bytes to each in-memory page */
+ i16 nReserve; /* Number of unused bytes at end of each page */
+ u32 vfsFlags; /* Flags for sqlite3_vfs.xOpen() */
+ u32 sectorSize; /* Assumed sector size during rollback */
+ int pageSize; /* Number of bytes in a page */
+ Pgno mxPgno; /* Maximum allowed size of the database */
+ i64 journalSizeLimit; /* Size limit for persistent journal files */
+ char *zFilename; /* Name of the database file */
+ char *zJournal; /* Name of the journal file */
+ int (*xBusyHandler)(void*); /* Function to call when busy */
+ void *pBusyHandlerArg; /* Context argument for xBusyHandler */
+ int aStat[3]; /* Total cache hits, misses and writes */
+#ifdef SQLITE_TEST
+ int nRead; /* Database pages read */
+#endif
+ void (*xReiniter)(DbPage*); /* Call this routine when reloading pages */
+#ifdef SQLITE_HAS_CODEC
+ void *(*xCodec)(void*,void*,Pgno,int); /* Routine for en/decoding data */
+ void (*xCodecSizeChng)(void*,int,int); /* Notify of page size changes */
+ void (*xCodecFree)(void*); /* Destructor for the codec */
+ void *pCodec; /* First argument to xCodec... methods */
+#endif
+ char *pTmpSpace; /* Pager.pageSize bytes of space for tmp use */
+ PCache *pPCache; /* Pointer to page cache object */
+#ifndef SQLITE_OMIT_WAL
+ Wal *pWal; /* Write-ahead log used by "journal_mode=wal" */
+ char *zWal; /* File name for write-ahead log */
+#endif
+};
+
+/*
+** Indexes for use with Pager.aStat[]. The Pager.aStat[] array contains
+** the values accessed by passing SQLITE_DBSTATUS_CACHE_HIT, CACHE_MISS
+** or CACHE_WRITE to sqlite3_db_status().
+*/
+#define PAGER_STAT_HIT 0
+#define PAGER_STAT_MISS 1
+#define PAGER_STAT_WRITE 2
+
+/*
+** The following global variables hold counters used for
+** testing purposes only. These variables do not exist in
+** a non-testing build. These variables are not thread-safe.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_pager_readdb_count = 0; /* Number of full pages read from DB */
+SQLITE_API int sqlite3_pager_writedb_count = 0; /* Number of full pages written to DB */
+SQLITE_API int sqlite3_pager_writej_count = 0; /* Number of pages written to journal */
+# define PAGER_INCR(v) v++
+#else
+# define PAGER_INCR(v)
+#endif
+
+
+
+/*
+** Journal files begin with the following magic string. The data
+** was obtained from /dev/random. It is used only as a sanity check.
+**
+** Since version 2.8.0, the journal format contains additional sanity
+** checking information. If the power fails while the journal is being
+** written, semi-random garbage data might appear in the journal
+** file after power is restored. If an attempt is then made
+** to roll the journal back, the database could be corrupted. The additional
+** sanity checking data is an attempt to discover the garbage in the
+** journal and ignore it.
+**
+** The sanity checking information for the new journal format consists
+** of a 32-bit checksum on each page of data. The checksum covers both
+** the page number and the pPager->pageSize bytes of data for the page.
+** This cksum is initialized to a 32-bit random value that appears in the
+** journal file right after the header. The random initializer is important,
+** because garbage data that appears at the end of a journal is likely
+** data that was once in other files that have now been deleted. If the
+** garbage data came from an obsolete journal file, the checksums might
+** be correct. But by initializing the checksum to random value which
+** is different for every journal, we minimize that risk.
+*/
+static const unsigned char aJournalMagic[] = {
+ 0xd9, 0xd5, 0x05, 0xf9, 0x20, 0xa1, 0x63, 0xd7,
+};
+
+/*
+** The size of the of each page record in the journal is given by
+** the following macro.
+*/
+#define JOURNAL_PG_SZ(pPager) ((pPager->pageSize) + 8)
+
+/*
+** The journal header size for this pager. This is usually the same
+** size as a single disk sector. See also setSectorSize().
+*/
+#define JOURNAL_HDR_SZ(pPager) (pPager->sectorSize)
+
+/*
+** The macro MEMDB is true if we are dealing with an in-memory database.
+** We do this as a macro so that if the SQLITE_OMIT_MEMORYDB macro is set,
+** the value of MEMDB will be a constant and the compiler will optimize
+** out code that would never execute.
+*/
+#ifdef SQLITE_OMIT_MEMORYDB
+# define MEMDB 0
+#else
+# define MEMDB pPager->memDb
+#endif
+
+/*
+** The macro USEFETCH is true if we are allowed to use the xFetch and xUnfetch
+** interfaces to access the database using memory-mapped I/O.
+*/
+#if SQLITE_MAX_MMAP_SIZE>0
+# define USEFETCH(x) ((x)->bUseFetch)
+#else
+# define USEFETCH(x) 0
+#endif
+
+/*
+** The maximum legal page number is (2^31 - 1).
+*/
+#define PAGER_MAX_PGNO 2147483647
+
+/*
+** The argument to this macro is a file descriptor (type sqlite3_file*).
+** Return 0 if it is not open, or non-zero (but not 1) if it is.
+**
+** This is so that expressions can be written as:
+**
+** if( isOpen(pPager->jfd) ){ ...
+**
+** instead of
+**
+** if( pPager->jfd->pMethods ){ ...
+*/
+#define isOpen(pFd) ((pFd)->pMethods)
+
+/*
+** Return true if this pager uses a write-ahead log instead of the usual
+** rollback journal. Otherwise false.
+*/
+#ifndef SQLITE_OMIT_WAL
+static int pagerUseWal(Pager *pPager){
+ return (pPager->pWal!=0);
+}
+#else
+# define pagerUseWal(x) 0
+# define pagerRollbackWal(x) 0
+# define pagerWalFrames(v,w,x,y) 0
+# define pagerOpenWalIfPresent(z) SQLITE_OK
+# define pagerBeginReadTransaction(z) SQLITE_OK
+#endif
+
+#ifndef NDEBUG
+/*
+** Usage:
+**
+** assert( assert_pager_state(pPager) );
+**
+** This function runs many asserts to try to find inconsistencies in
+** the internal state of the Pager object.
+*/
+static int assert_pager_state(Pager *p){
+ Pager *pPager = p;
+
+ /* State must be valid. */
+ assert( p->eState==PAGER_OPEN
+ || p->eState==PAGER_READER
+ || p->eState==PAGER_WRITER_LOCKED
+ || p->eState==PAGER_WRITER_CACHEMOD
+ || p->eState==PAGER_WRITER_DBMOD
+ || p->eState==PAGER_WRITER_FINISHED
+ || p->eState==PAGER_ERROR
+ );
+
+ /* Regardless of the current state, a temp-file connection always behaves
+ ** as if it has an exclusive lock on the database file. It never updates
+ ** the change-counter field, so the changeCountDone flag is always set.
+ */
+ assert( p->tempFile==0 || p->eLock==EXCLUSIVE_LOCK );
+ assert( p->tempFile==0 || pPager->changeCountDone );
+
+ /* If the useJournal flag is clear, the journal-mode must be "OFF".
+ ** And if the journal-mode is "OFF", the journal file must not be open.
+ */
+ assert( p->journalMode==PAGER_JOURNALMODE_OFF || p->useJournal );
+ assert( p->journalMode!=PAGER_JOURNALMODE_OFF || !isOpen(p->jfd) );
+
+ /* Check that MEMDB implies noSync. And an in-memory journal. Since
+ ** this means an in-memory pager performs no IO at all, it cannot encounter
+ ** either SQLITE_IOERR or SQLITE_FULL during rollback or while finalizing
+ ** a journal file. (although the in-memory journal implementation may
+ ** return SQLITE_IOERR_NOMEM while the journal file is being written). It
+ ** is therefore not possible for an in-memory pager to enter the ERROR
+ ** state.
+ */
+ if( MEMDB ){
+ assert( p->noSync );
+ assert( p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_MEMORY
+ );
+ assert( p->eState!=PAGER_ERROR && p->eState!=PAGER_OPEN );
+ assert( pagerUseWal(p)==0 );
+ }
+
+ /* If changeCountDone is set, a RESERVED lock or greater must be held
+ ** on the file.
+ */
+ assert( pPager->changeCountDone==0 || pPager->eLock>=RESERVED_LOCK );
+ assert( p->eLock!=PENDING_LOCK );
+
+ switch( p->eState ){
+ case PAGER_OPEN:
+ assert( !MEMDB );
+ assert( pPager->errCode==SQLITE_OK );
+ assert( sqlite3PcacheRefCount(pPager->pPCache)==0 || pPager->tempFile );
+ break;
+
+ case PAGER_READER:
+ assert( pPager->errCode==SQLITE_OK );
+ assert( p->eLock!=UNKNOWN_LOCK );
+ assert( p->eLock>=SHARED_LOCK );
+ break;
+
+ case PAGER_WRITER_LOCKED:
+ assert( p->eLock!=UNKNOWN_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ if( !pagerUseWal(pPager) ){
+ assert( p->eLock>=RESERVED_LOCK );
+ }
+ assert( pPager->dbSize==pPager->dbOrigSize );
+ assert( pPager->dbOrigSize==pPager->dbFileSize );
+ assert( pPager->dbOrigSize==pPager->dbHintSize );
+ assert( pPager->setMaster==0 );
+ break;
+
+ case PAGER_WRITER_CACHEMOD:
+ assert( p->eLock!=UNKNOWN_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ if( !pagerUseWal(pPager) ){
+ /* It is possible that if journal_mode=wal here that neither the
+ ** journal file nor the WAL file are open. This happens during
+ ** a rollback transaction that switches from journal_mode=off
+ ** to journal_mode=wal.
+ */
+ assert( p->eLock>=RESERVED_LOCK );
+ assert( isOpen(p->jfd)
+ || p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ }
+ assert( pPager->dbOrigSize==pPager->dbFileSize );
+ assert( pPager->dbOrigSize==pPager->dbHintSize );
+ break;
+
+ case PAGER_WRITER_DBMOD:
+ assert( p->eLock==EXCLUSIVE_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ assert( !pagerUseWal(pPager) );
+ assert( p->eLock>=EXCLUSIVE_LOCK );
+ assert( isOpen(p->jfd)
+ || p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ assert( pPager->dbOrigSize<=pPager->dbHintSize );
+ break;
+
+ case PAGER_WRITER_FINISHED:
+ assert( p->eLock==EXCLUSIVE_LOCK );
+ assert( pPager->errCode==SQLITE_OK );
+ assert( !pagerUseWal(pPager) );
+ assert( isOpen(p->jfd)
+ || p->journalMode==PAGER_JOURNALMODE_OFF
+ || p->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ break;
+
+ case PAGER_ERROR:
+ /* There must be at least one outstanding reference to the pager if
+ ** in ERROR state. Otherwise the pager should have already dropped
+ ** back to OPEN state.
+ */
+ assert( pPager->errCode!=SQLITE_OK );
+ assert( sqlite3PcacheRefCount(pPager->pPCache)>0 );
+ break;
+ }
+
+ return 1;
+}
+#endif /* ifndef NDEBUG */
+
+#ifdef SQLITE_DEBUG
+/*
+** Return a pointer to a human readable string in a static buffer
+** containing the state of the Pager object passed as an argument. This
+** is intended to be used within debuggers. For example, as an alternative
+** to "print *pPager" in gdb:
+**
+** (gdb) printf "%s", print_pager_state(pPager)
+*/
+static char *print_pager_state(Pager *p){
+ static char zRet[1024];
+
+ sqlite3_snprintf(1024, zRet,
+ "Filename: %s\n"
+ "State: %s errCode=%d\n"
+ "Lock: %s\n"
+ "Locking mode: locking_mode=%s\n"
+ "Journal mode: journal_mode=%s\n"
+ "Backing store: tempFile=%d memDb=%d useJournal=%d\n"
+ "Journal: journalOff=%lld journalHdr=%lld\n"
+ "Size: dbsize=%d dbOrigSize=%d dbFileSize=%d\n"
+ , p->zFilename
+ , p->eState==PAGER_OPEN ? "OPEN" :
+ p->eState==PAGER_READER ? "READER" :
+ p->eState==PAGER_WRITER_LOCKED ? "WRITER_LOCKED" :
+ p->eState==PAGER_WRITER_CACHEMOD ? "WRITER_CACHEMOD" :
+ p->eState==PAGER_WRITER_DBMOD ? "WRITER_DBMOD" :
+ p->eState==PAGER_WRITER_FINISHED ? "WRITER_FINISHED" :
+ p->eState==PAGER_ERROR ? "ERROR" : "?error?"
+ , (int)p->errCode
+ , p->eLock==NO_LOCK ? "NO_LOCK" :
+ p->eLock==RESERVED_LOCK ? "RESERVED" :
+ p->eLock==EXCLUSIVE_LOCK ? "EXCLUSIVE" :
+ p->eLock==SHARED_LOCK ? "SHARED" :
+ p->eLock==UNKNOWN_LOCK ? "UNKNOWN" : "?error?"
+ , p->exclusiveMode ? "exclusive" : "normal"
+ , p->journalMode==PAGER_JOURNALMODE_MEMORY ? "memory" :
+ p->journalMode==PAGER_JOURNALMODE_OFF ? "off" :
+ p->journalMode==PAGER_JOURNALMODE_DELETE ? "delete" :
+ p->journalMode==PAGER_JOURNALMODE_PERSIST ? "persist" :
+ p->journalMode==PAGER_JOURNALMODE_TRUNCATE ? "truncate" :
+ p->journalMode==PAGER_JOURNALMODE_WAL ? "wal" : "?error?"
+ , (int)p->tempFile, (int)p->memDb, (int)p->useJournal
+ , p->journalOff, p->journalHdr
+ , (int)p->dbSize, (int)p->dbOrigSize, (int)p->dbFileSize
+ );
+
+ return zRet;
+}
+#endif
+
+/*
+** Return true if it is necessary to write page *pPg into the sub-journal.
+** A page needs to be written into the sub-journal if there exists one
+** or more open savepoints for which:
+**
+** * The page-number is less than or equal to PagerSavepoint.nOrig, and
+** * The bit corresponding to the page-number is not set in
+** PagerSavepoint.pInSavepoint.
+*/
+static int subjRequiresPage(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ PagerSavepoint *p;
+ Pgno pgno = pPg->pgno;
+ int i;
+ for(i=0; inSavepoint; i++){
+ p = &pPager->aSavepoint[i];
+ if( p->nOrig>=pgno && 0==sqlite3BitvecTest(p->pInSavepoint, pgno) ){
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/*
+** Return true if the page is already in the journal file.
+*/
+static int pageInJournal(Pager *pPager, PgHdr *pPg){
+ return sqlite3BitvecTest(pPager->pInJournal, pPg->pgno);
+}
+
+/*
+** Read a 32-bit integer from the given file descriptor. Store the integer
+** that is read in *pRes. Return SQLITE_OK if everything worked, or an
+** error code is something goes wrong.
+**
+** All values are stored on disk as big-endian.
+*/
+static int read32bits(sqlite3_file *fd, i64 offset, u32 *pRes){
+ unsigned char ac[4];
+ int rc = sqlite3OsRead(fd, ac, sizeof(ac), offset);
+ if( rc==SQLITE_OK ){
+ *pRes = sqlite3Get4byte(ac);
+ }
+ return rc;
+}
+
+/*
+** Write a 32-bit integer into a string buffer in big-endian byte order.
+*/
+#define put32bits(A,B) sqlite3Put4byte((u8*)A,B)
+
+
+/*
+** Write a 32-bit integer into the given file descriptor. Return SQLITE_OK
+** on success or an error code is something goes wrong.
+*/
+static int write32bits(sqlite3_file *fd, i64 offset, u32 val){
+ char ac[4];
+ put32bits(ac, val);
+ return sqlite3OsWrite(fd, ac, 4, offset);
+}
+
+/*
+** Unlock the database file to level eLock, which must be either NO_LOCK
+** or SHARED_LOCK. Regardless of whether or not the call to xUnlock()
+** succeeds, set the Pager.eLock variable to match the (attempted) new lock.
+**
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is
+** called, do not modify it. See the comment above the #define of
+** UNKNOWN_LOCK for an explanation of this.
+*/
+static int pagerUnlockDb(Pager *pPager, int eLock){
+ int rc = SQLITE_OK;
+
+ assert( !pPager->exclusiveMode || pPager->eLock==eLock );
+ assert( eLock==NO_LOCK || eLock==SHARED_LOCK );
+ assert( eLock!=NO_LOCK || pagerUseWal(pPager)==0 );
+ if( isOpen(pPager->fd) ){
+ assert( pPager->eLock>=eLock );
+ rc = pPager->noLock ? SQLITE_OK : sqlite3OsUnlock(pPager->fd, eLock);
+ if( pPager->eLock!=UNKNOWN_LOCK ){
+ pPager->eLock = (u8)eLock;
+ }
+ IOTRACE(("UNLOCK %p %d\n", pPager, eLock))
+ }
+ return rc;
+}
+
+/*
+** Lock the database file to level eLock, which must be either SHARED_LOCK,
+** RESERVED_LOCK or EXCLUSIVE_LOCK. If the caller is successful, set the
+** Pager.eLock variable to the new locking state.
+**
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is
+** called, do not modify it unless the new locking state is EXCLUSIVE_LOCK.
+** See the comment above the #define of UNKNOWN_LOCK for an explanation
+** of this.
+*/
+static int pagerLockDb(Pager *pPager, int eLock){
+ int rc = SQLITE_OK;
+
+ assert( eLock==SHARED_LOCK || eLock==RESERVED_LOCK || eLock==EXCLUSIVE_LOCK );
+ if( pPager->eLockeLock==UNKNOWN_LOCK ){
+ rc = pPager->noLock ? SQLITE_OK : sqlite3OsLock(pPager->fd, eLock);
+ if( rc==SQLITE_OK && (pPager->eLock!=UNKNOWN_LOCK||eLock==EXCLUSIVE_LOCK) ){
+ pPager->eLock = (u8)eLock;
+ IOTRACE(("LOCK %p %d\n", pPager, eLock))
+ }
+ }
+ return rc;
+}
+
+/*
+** This function determines whether or not the atomic-write optimization
+** can be used with this pager. The optimization can be used if:
+**
+** (a) the value returned by OsDeviceCharacteristics() indicates that
+** a database page may be written atomically, and
+** (b) the value returned by OsSectorSize() is less than or equal
+** to the page size.
+**
+** The optimization is also always enabled for temporary files. It is
+** an error to call this function if pPager is opened on an in-memory
+** database.
+**
+** If the optimization cannot be used, 0 is returned. If it can be used,
+** then the value returned is the size of the journal file when it
+** contains rollback data for exactly one page.
+*/
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+static int jrnlBufferSize(Pager *pPager){
+ assert( !MEMDB );
+ if( !pPager->tempFile ){
+ int dc; /* Device characteristics */
+ int nSector; /* Sector size */
+ int szPage; /* Page size */
+
+ assert( isOpen(pPager->fd) );
+ dc = sqlite3OsDeviceCharacteristics(pPager->fd);
+ nSector = pPager->sectorSize;
+ szPage = pPager->pageSize;
+
+ assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
+ assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
+ if( 0==(dc&(SQLITE_IOCAP_ATOMIC|(szPage>>8)) || nSector>szPage) ){
+ return 0;
+ }
+ }
+
+ return JOURNAL_HDR_SZ(pPager) + JOURNAL_PG_SZ(pPager);
+}
+#endif
+
+/*
+** If SQLITE_CHECK_PAGES is defined then we do some sanity checking
+** on the cache using a hash function. This is used for testing
+** and debugging only.
+*/
+#ifdef SQLITE_CHECK_PAGES
+/*
+** Return a 32-bit hash of the page data for pPage.
+*/
+static u32 pager_datahash(int nByte, unsigned char *pData){
+ u32 hash = 0;
+ int i;
+ for(i=0; ipPager->pageSize, (unsigned char *)pPage->pData);
+}
+static void pager_set_pagehash(PgHdr *pPage){
+ pPage->pageHash = pager_pagehash(pPage);
+}
+
+/*
+** The CHECK_PAGE macro takes a PgHdr* as an argument. If SQLITE_CHECK_PAGES
+** is defined, and NDEBUG is not defined, an assert() statement checks
+** that the page is either dirty or still matches the calculated page-hash.
+*/
+#define CHECK_PAGE(x) checkPage(x)
+static void checkPage(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ assert( pPager->eState!=PAGER_ERROR );
+ assert( (pPg->flags&PGHDR_DIRTY) || pPg->pageHash==pager_pagehash(pPg) );
+}
+
+#else
+#define pager_datahash(X,Y) 0
+#define pager_pagehash(X) 0
+#define pager_set_pagehash(X)
+#define CHECK_PAGE(x)
+#endif /* SQLITE_CHECK_PAGES */
+
+/*
+** When this is called the journal file for pager pPager must be open.
+** This function attempts to read a master journal file name from the
+** end of the file and, if successful, copies it into memory supplied
+** by the caller. See comments above writeMasterJournal() for the format
+** used to store a master journal file name at the end of a journal file.
+**
+** zMaster must point to a buffer of at least nMaster bytes allocated by
+** the caller. This should be sqlite3_vfs.mxPathname+1 (to ensure there is
+** enough space to write the master journal name). If the master journal
+** name in the journal is longer than nMaster bytes (including a
+** nul-terminator), then this is handled as if no master journal name
+** were present in the journal.
+**
+** If a master journal file name is present at the end of the journal
+** file, then it is copied into the buffer pointed to by zMaster. A
+** nul-terminator byte is appended to the buffer following the master
+** journal file name.
+**
+** If it is determined that no master journal file name is present
+** zMaster[0] is set to 0 and SQLITE_OK returned.
+**
+** If an error occurs while reading from the journal file, an SQLite
+** error code is returned.
+*/
+static int readMasterJournal(sqlite3_file *pJrnl, char *zMaster, u32 nMaster){
+ int rc; /* Return code */
+ u32 len; /* Length in bytes of master journal name */
+ i64 szJ; /* Total size in bytes of journal file pJrnl */
+ u32 cksum; /* MJ checksum value read from journal */
+ u32 u; /* Unsigned loop counter */
+ unsigned char aMagic[8]; /* A buffer to hold the magic header */
+ zMaster[0] = '\0';
+
+ if( SQLITE_OK!=(rc = sqlite3OsFileSize(pJrnl, &szJ))
+ || szJ<16
+ || SQLITE_OK!=(rc = read32bits(pJrnl, szJ-16, &len))
+ || len>=nMaster
+ || len==0
+ || SQLITE_OK!=(rc = read32bits(pJrnl, szJ-12, &cksum))
+ || SQLITE_OK!=(rc = sqlite3OsRead(pJrnl, aMagic, 8, szJ-8))
+ || memcmp(aMagic, aJournalMagic, 8)
+ || SQLITE_OK!=(rc = sqlite3OsRead(pJrnl, zMaster, len, szJ-16-len))
+ ){
+ return rc;
+ }
+
+ /* See if the checksum matches the master journal name */
+ for(u=0; ujournalOff, assuming a sector
+** size of pPager->sectorSize bytes.
+**
+** i.e for a sector size of 512:
+**
+** Pager.journalOff Return value
+** ---------------------------------------
+** 0 0
+** 512 512
+** 100 512
+** 2000 2048
+**
+*/
+static i64 journalHdrOffset(Pager *pPager){
+ i64 offset = 0;
+ i64 c = pPager->journalOff;
+ if( c ){
+ offset = ((c-1)/JOURNAL_HDR_SZ(pPager) + 1) * JOURNAL_HDR_SZ(pPager);
+ }
+ assert( offset%JOURNAL_HDR_SZ(pPager)==0 );
+ assert( offset>=c );
+ assert( (offset-c)jfd) );
+ if( pPager->journalOff ){
+ const i64 iLimit = pPager->journalSizeLimit; /* Local cache of jsl */
+
+ IOTRACE(("JZEROHDR %p\n", pPager))
+ if( doTruncate || iLimit==0 ){
+ rc = sqlite3OsTruncate(pPager->jfd, 0);
+ }else{
+ static const char zeroHdr[28] = {0};
+ rc = sqlite3OsWrite(pPager->jfd, zeroHdr, sizeof(zeroHdr), 0);
+ }
+ if( rc==SQLITE_OK && !pPager->noSync ){
+ rc = sqlite3OsSync(pPager->jfd, SQLITE_SYNC_DATAONLY|pPager->syncFlags);
+ }
+
+ /* At this point the transaction is committed but the write lock
+ ** is still held on the file. If there is a size limit configured for
+ ** the persistent journal and the journal file currently consumes more
+ ** space than that limit allows for, truncate it now. There is no need
+ ** to sync the file following this operation.
+ */
+ if( rc==SQLITE_OK && iLimit>0 ){
+ i64 sz;
+ rc = sqlite3OsFileSize(pPager->jfd, &sz);
+ if( rc==SQLITE_OK && sz>iLimit ){
+ rc = sqlite3OsTruncate(pPager->jfd, iLimit);
+ }
+ }
+ }
+ return rc;
+}
+
+/*
+** The journal file must be open when this routine is called. A journal
+** header (JOURNAL_HDR_SZ bytes) is written into the journal file at the
+** current location.
+**
+** The format for the journal header is as follows:
+** - 8 bytes: Magic identifying journal format.
+** - 4 bytes: Number of records in journal, or -1 no-sync mode is on.
+** - 4 bytes: Random number used for page hash.
+** - 4 bytes: Initial database page count.
+** - 4 bytes: Sector size used by the process that wrote this journal.
+** - 4 bytes: Database page size.
+**
+** Followed by (JOURNAL_HDR_SZ - 28) bytes of unused space.
+*/
+static int writeJournalHdr(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+ char *zHeader = pPager->pTmpSpace; /* Temporary space used to build header */
+ u32 nHeader = (u32)pPager->pageSize;/* Size of buffer pointed to by zHeader */
+ u32 nWrite; /* Bytes of header sector written */
+ int ii; /* Loop counter */
+
+ assert( isOpen(pPager->jfd) ); /* Journal file must be open. */
+
+ if( nHeader>JOURNAL_HDR_SZ(pPager) ){
+ nHeader = JOURNAL_HDR_SZ(pPager);
+ }
+
+ /* If there are active savepoints and any of them were created
+ ** since the most recent journal header was written, update the
+ ** PagerSavepoint.iHdrOffset fields now.
+ */
+ for(ii=0; iinSavepoint; ii++){
+ if( pPager->aSavepoint[ii].iHdrOffset==0 ){
+ pPager->aSavepoint[ii].iHdrOffset = pPager->journalOff;
+ }
+ }
+
+ pPager->journalHdr = pPager->journalOff = journalHdrOffset(pPager);
+
+ /*
+ ** Write the nRec Field - the number of page records that follow this
+ ** journal header. Normally, zero is written to this value at this time.
+ ** After the records are added to the journal (and the journal synced,
+ ** if in full-sync mode), the zero is overwritten with the true number
+ ** of records (see syncJournal()).
+ **
+ ** A faster alternative is to write 0xFFFFFFFF to the nRec field. When
+ ** reading the journal this value tells SQLite to assume that the
+ ** rest of the journal file contains valid page records. This assumption
+ ** is dangerous, as if a failure occurred whilst writing to the journal
+ ** file it may contain some garbage data. There are two scenarios
+ ** where this risk can be ignored:
+ **
+ ** * When the pager is in no-sync mode. Corruption can follow a
+ ** power failure in this case anyway.
+ **
+ ** * When the SQLITE_IOCAP_SAFE_APPEND flag is set. This guarantees
+ ** that garbage data is never appended to the journal file.
+ */
+ assert( isOpen(pPager->fd) || pPager->noSync );
+ if( pPager->noSync || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
+ || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND)
+ ){
+ memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
+ put32bits(&zHeader[sizeof(aJournalMagic)], 0xffffffff);
+ }else{
+ memset(zHeader, 0, sizeof(aJournalMagic)+4);
+ }
+
+ /* The random check-hash initializer */
+ sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
+ put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
+ /* The initial database size */
+ put32bits(&zHeader[sizeof(aJournalMagic)+8], pPager->dbOrigSize);
+ /* The assumed sector size for this process */
+ put32bits(&zHeader[sizeof(aJournalMagic)+12], pPager->sectorSize);
+
+ /* The page size */
+ put32bits(&zHeader[sizeof(aJournalMagic)+16], pPager->pageSize);
+
+ /* Initializing the tail of the buffer is not necessary. Everything
+ ** works find if the following memset() is omitted. But initializing
+ ** the memory prevents valgrind from complaining, so we are willing to
+ ** take the performance hit.
+ */
+ memset(&zHeader[sizeof(aJournalMagic)+20], 0,
+ nHeader-(sizeof(aJournalMagic)+20));
+
+ /* In theory, it is only necessary to write the 28 bytes that the
+ ** journal header consumes to the journal file here. Then increment the
+ ** Pager.journalOff variable by JOURNAL_HDR_SZ so that the next
+ ** record is written to the following sector (leaving a gap in the file
+ ** that will be implicitly filled in by the OS).
+ **
+ ** However it has been discovered that on some systems this pattern can
+ ** be significantly slower than contiguously writing data to the file,
+ ** even if that means explicitly writing data to the block of
+ ** (JOURNAL_HDR_SZ - 28) bytes that will not be used. So that is what
+ ** is done.
+ **
+ ** The loop is required here in case the sector-size is larger than the
+ ** database page size. Since the zHeader buffer is only Pager.pageSize
+ ** bytes in size, more than one call to sqlite3OsWrite() may be required
+ ** to populate the entire journal header sector.
+ */
+ for(nWrite=0; rc==SQLITE_OK&&nWritejournalHdr, nHeader))
+ rc = sqlite3OsWrite(pPager->jfd, zHeader, nHeader, pPager->journalOff);
+ assert( pPager->journalHdr <= pPager->journalOff );
+ pPager->journalOff += nHeader;
+ }
+
+ return rc;
+}
+
+/*
+** The journal file must be open when this is called. A journal header file
+** (JOURNAL_HDR_SZ bytes) is read from the current location in the journal
+** file. The current location in the journal file is given by
+** pPager->journalOff. See comments above function writeJournalHdr() for
+** a description of the journal header format.
+**
+** If the header is read successfully, *pNRec is set to the number of
+** page records following this header and *pDbSize is set to the size of the
+** database before the transaction began, in pages. Also, pPager->cksumInit
+** is set to the value read from the journal header. SQLITE_OK is returned
+** in this case.
+**
+** If the journal header file appears to be corrupted, SQLITE_DONE is
+** returned and *pNRec and *PDbSize are undefined. If JOURNAL_HDR_SZ bytes
+** cannot be read from the journal file an error code is returned.
+*/
+static int readJournalHdr(
+ Pager *pPager, /* Pager object */
+ int isHot,
+ i64 journalSize, /* Size of the open journal file in bytes */
+ u32 *pNRec, /* OUT: Value read from the nRec field */
+ u32 *pDbSize /* OUT: Value of original database size field */
+){
+ int rc; /* Return code */
+ unsigned char aMagic[8]; /* A buffer to hold the magic header */
+ i64 iHdrOff; /* Offset of journal header being read */
+
+ assert( isOpen(pPager->jfd) ); /* Journal file must be open. */
+
+ /* Advance Pager.journalOff to the start of the next sector. If the
+ ** journal file is too small for there to be a header stored at this
+ ** point, return SQLITE_DONE.
+ */
+ pPager->journalOff = journalHdrOffset(pPager);
+ if( pPager->journalOff+JOURNAL_HDR_SZ(pPager) > journalSize ){
+ return SQLITE_DONE;
+ }
+ iHdrOff = pPager->journalOff;
+
+ /* Read in the first 8 bytes of the journal header. If they do not match
+ ** the magic string found at the start of each journal header, return
+ ** SQLITE_DONE. If an IO error occurs, return an error code. Otherwise,
+ ** proceed.
+ */
+ if( isHot || iHdrOff!=pPager->journalHdr ){
+ rc = sqlite3OsRead(pPager->jfd, aMagic, sizeof(aMagic), iHdrOff);
+ if( rc ){
+ return rc;
+ }
+ if( memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
+ return SQLITE_DONE;
+ }
+ }
+
+ /* Read the first three 32-bit fields of the journal header: The nRec
+ ** field, the checksum-initializer and the database size at the start
+ ** of the transaction. Return an error code if anything goes wrong.
+ */
+ if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+8, pNRec))
+ || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+12, &pPager->cksumInit))
+ || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+16, pDbSize))
+ ){
+ return rc;
+ }
+
+ if( pPager->journalOff==0 ){
+ u32 iPageSize; /* Page-size field of journal header */
+ u32 iSectorSize; /* Sector-size field of journal header */
+
+ /* Read the page-size and sector-size journal header fields. */
+ if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+20, &iSectorSize))
+ || SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+24, &iPageSize))
+ ){
+ return rc;
+ }
+
+ /* Versions of SQLite prior to 3.5.8 set the page-size field of the
+ ** journal header to zero. In this case, assume that the Pager.pageSize
+ ** variable is already set to the correct page size.
+ */
+ if( iPageSize==0 ){
+ iPageSize = pPager->pageSize;
+ }
+
+ /* Check that the values read from the page-size and sector-size fields
+ ** are within range. To be 'in range', both values need to be a power
+ ** of two greater than or equal to 512 or 32, and not greater than their
+ ** respective compile time maximum limits.
+ */
+ if( iPageSize<512 || iSectorSize<32
+ || iPageSize>SQLITE_MAX_PAGE_SIZE || iSectorSize>MAX_SECTOR_SIZE
+ || ((iPageSize-1)&iPageSize)!=0 || ((iSectorSize-1)&iSectorSize)!=0
+ ){
+ /* If the either the page-size or sector-size in the journal-header is
+ ** invalid, then the process that wrote the journal-header must have
+ ** crashed before the header was synced. In this case stop reading
+ ** the journal file here.
+ */
+ return SQLITE_DONE;
+ }
+
+ /* Update the page-size to match the value read from the journal.
+ ** Use a testcase() macro to make sure that malloc failure within
+ ** PagerSetPagesize() is tested.
+ */
+ rc = sqlite3PagerSetPagesize(pPager, &iPageSize, -1);
+ testcase( rc!=SQLITE_OK );
+
+ /* Update the assumed sector-size to match the value used by
+ ** the process that created this journal. If this journal was
+ ** created by a process other than this one, then this routine
+ ** is being called from within pager_playback(). The local value
+ ** of Pager.sectorSize is restored at the end of that routine.
+ */
+ pPager->sectorSize = iSectorSize;
+ }
+
+ pPager->journalOff += JOURNAL_HDR_SZ(pPager);
+ return rc;
+}
+
+
+/*
+** Write the supplied master journal name into the journal file for pager
+** pPager at the current location. The master journal name must be the last
+** thing written to a journal file. If the pager is in full-sync mode, the
+** journal file descriptor is advanced to the next sector boundary before
+** anything is written. The format is:
+**
+** + 4 bytes: PAGER_MJ_PGNO.
+** + N bytes: Master journal filename in utf-8.
+** + 4 bytes: N (length of master journal name in bytes, no nul-terminator).
+** + 4 bytes: Master journal name checksum.
+** + 8 bytes: aJournalMagic[].
+**
+** The master journal page checksum is the sum of the bytes in the master
+** journal name, where each byte is interpreted as a signed 8-bit integer.
+**
+** If zMaster is a NULL pointer (occurs for a single database transaction),
+** this call is a no-op.
+*/
+static int writeMasterJournal(Pager *pPager, const char *zMaster){
+ int rc; /* Return code */
+ int nMaster; /* Length of string zMaster */
+ i64 iHdrOff; /* Offset of header in journal file */
+ i64 jrnlSize; /* Size of journal file on disk */
+ u32 cksum = 0; /* Checksum of string zMaster */
+
+ assert( pPager->setMaster==0 );
+ assert( !pagerUseWal(pPager) );
+
+ if( !zMaster
+ || pPager->journalMode==PAGER_JOURNALMODE_MEMORY
+ || !isOpen(pPager->jfd)
+ ){
+ return SQLITE_OK;
+ }
+ pPager->setMaster = 1;
+ assert( pPager->journalHdr <= pPager->journalOff );
+
+ /* Calculate the length in bytes and the checksum of zMaster */
+ for(nMaster=0; zMaster[nMaster]; nMaster++){
+ cksum += zMaster[nMaster];
+ }
+
+ /* If in full-sync mode, advance to the next disk sector before writing
+ ** the master journal name. This is in case the previous page written to
+ ** the journal has already been synced.
+ */
+ if( pPager->fullSync ){
+ pPager->journalOff = journalHdrOffset(pPager);
+ }
+ iHdrOff = pPager->journalOff;
+
+ /* Write the master journal data to the end of the journal file. If
+ ** an error occurs, return the error code to the caller.
+ */
+ if( (0 != (rc = write32bits(pPager->jfd, iHdrOff, PAGER_MJ_PGNO(pPager))))
+ || (0 != (rc = sqlite3OsWrite(pPager->jfd, zMaster, nMaster, iHdrOff+4)))
+ || (0 != (rc = write32bits(pPager->jfd, iHdrOff+4+nMaster, nMaster)))
+ || (0 != (rc = write32bits(pPager->jfd, iHdrOff+4+nMaster+4, cksum)))
+ || (0 != (rc = sqlite3OsWrite(pPager->jfd, aJournalMagic, 8, iHdrOff+4+nMaster+8)))
+ ){
+ return rc;
+ }
+ pPager->journalOff += (nMaster+20);
+
+ /* If the pager is in peristent-journal mode, then the physical
+ ** journal-file may extend past the end of the master-journal name
+ ** and 8 bytes of magic data just written to the file. This is
+ ** dangerous because the code to rollback a hot-journal file
+ ** will not be able to find the master-journal name to determine
+ ** whether or not the journal is hot.
+ **
+ ** Easiest thing to do in this scenario is to truncate the journal
+ ** file to the required size.
+ */
+ if( SQLITE_OK==(rc = sqlite3OsFileSize(pPager->jfd, &jrnlSize))
+ && jrnlSize>pPager->journalOff
+ ){
+ rc = sqlite3OsTruncate(pPager->jfd, pPager->journalOff);
+ }
+ return rc;
+}
+
+/*
+** Find a page in the hash table given its page number. Return
+** a pointer to the page or NULL if the requested page is not
+** already in memory.
+*/
+static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){
+ PgHdr *p = 0; /* Return value */
+
+ /* It is not possible for a call to PcacheFetch() with createFlag==0 to
+ ** fail, since no attempt to allocate dynamic memory will be made.
+ */
+ (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &p);
+ return p;
+}
+
+/*
+** Discard the entire contents of the in-memory page-cache.
+*/
+static void pager_reset(Pager *pPager){
+ sqlite3BackupRestart(pPager->pBackup);
+ sqlite3PcacheClear(pPager->pPCache);
+}
+
+/*
+** Free all structures in the Pager.aSavepoint[] array and set both
+** Pager.aSavepoint and Pager.nSavepoint to zero. Close the sub-journal
+** if it is open and the pager is not in exclusive mode.
+*/
+static void releaseAllSavepoints(Pager *pPager){
+ int ii; /* Iterator for looping through Pager.aSavepoint */
+ for(ii=0; iinSavepoint; ii++){
+ sqlite3BitvecDestroy(pPager->aSavepoint[ii].pInSavepoint);
+ }
+ if( !pPager->exclusiveMode || sqlite3IsMemJournal(pPager->sjfd) ){
+ sqlite3OsClose(pPager->sjfd);
+ }
+ sqlite3_free(pPager->aSavepoint);
+ pPager->aSavepoint = 0;
+ pPager->nSavepoint = 0;
+ pPager->nSubRec = 0;
+}
+
+/*
+** Set the bit number pgno in the PagerSavepoint.pInSavepoint
+** bitvecs of all open savepoints. Return SQLITE_OK if successful
+** or SQLITE_NOMEM if a malloc failure occurs.
+*/
+static int addToSavepointBitvecs(Pager *pPager, Pgno pgno){
+ int ii; /* Loop counter */
+ int rc = SQLITE_OK; /* Result code */
+
+ for(ii=0; iinSavepoint; ii++){
+ PagerSavepoint *p = &pPager->aSavepoint[ii];
+ if( pgno<=p->nOrig ){
+ rc |= sqlite3BitvecSet(p->pInSavepoint, pgno);
+ testcase( rc==SQLITE_NOMEM );
+ assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
+ }
+ }
+ return rc;
+}
+
+/*
+** This function is a no-op if the pager is in exclusive mode and not
+** in the ERROR state. Otherwise, it switches the pager to PAGER_OPEN
+** state.
+**
+** If the pager is not in exclusive-access mode, the database file is
+** completely unlocked. If the file is unlocked and the file-system does
+** not exhibit the UNDELETABLE_WHEN_OPEN property, the journal file is
+** closed (if it is open).
+**
+** If the pager is in ERROR state when this function is called, the
+** contents of the pager cache are discarded before switching back to
+** the OPEN state. Regardless of whether the pager is in exclusive-mode
+** or not, any journal file left in the file-system will be treated
+** as a hot-journal and rolled back the next time a read-transaction
+** is opened (by this or by any other connection).
+*/
+static void pager_unlock(Pager *pPager){
+
+ assert( pPager->eState==PAGER_READER
+ || pPager->eState==PAGER_OPEN
+ || pPager->eState==PAGER_ERROR
+ );
+
+ sqlite3BitvecDestroy(pPager->pInJournal);
+ pPager->pInJournal = 0;
+ releaseAllSavepoints(pPager);
+
+ if( pagerUseWal(pPager) ){
+ assert( !isOpen(pPager->jfd) );
+ sqlite3WalEndReadTransaction(pPager->pWal);
+ pPager->eState = PAGER_OPEN;
+ }else if( !pPager->exclusiveMode ){
+ int rc; /* Error code returned by pagerUnlockDb() */
+ int iDc = isOpen(pPager->fd)?sqlite3OsDeviceCharacteristics(pPager->fd):0;
+
+ /* If the operating system support deletion of open files, then
+ ** close the journal file when dropping the database lock. Otherwise
+ ** another connection with journal_mode=delete might delete the file
+ ** out from under us.
+ */
+ assert( (PAGER_JOURNALMODE_MEMORY & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_OFF & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_WAL & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_DELETE & 5)!=1 );
+ assert( (PAGER_JOURNALMODE_TRUNCATE & 5)==1 );
+ assert( (PAGER_JOURNALMODE_PERSIST & 5)==1 );
+ if( 0==(iDc & SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN)
+ || 1!=(pPager->journalMode & 5)
+ ){
+ sqlite3OsClose(pPager->jfd);
+ }
+
+ /* If the pager is in the ERROR state and the call to unlock the database
+ ** file fails, set the current lock to UNKNOWN_LOCK. See the comment
+ ** above the #define for UNKNOWN_LOCK for an explanation of why this
+ ** is necessary.
+ */
+ rc = pagerUnlockDb(pPager, NO_LOCK);
+ if( rc!=SQLITE_OK && pPager->eState==PAGER_ERROR ){
+ pPager->eLock = UNKNOWN_LOCK;
+ }
+
+ /* The pager state may be changed from PAGER_ERROR to PAGER_OPEN here
+ ** without clearing the error code. This is intentional - the error
+ ** code is cleared and the cache reset in the block below.
+ */
+ assert( pPager->errCode || pPager->eState!=PAGER_ERROR );
+ pPager->changeCountDone = 0;
+ pPager->eState = PAGER_OPEN;
+ }
+
+ /* If Pager.errCode is set, the contents of the pager cache cannot be
+ ** trusted. Now that there are no outstanding references to the pager,
+ ** it can safely move back to PAGER_OPEN state. This happens in both
+ ** normal and exclusive-locking mode.
+ */
+ if( pPager->errCode ){
+ assert( !MEMDB );
+ pager_reset(pPager);
+ pPager->changeCountDone = pPager->tempFile;
+ pPager->eState = PAGER_OPEN;
+ pPager->errCode = SQLITE_OK;
+ if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
+ }
+
+ pPager->journalOff = 0;
+ pPager->journalHdr = 0;
+ pPager->setMaster = 0;
+}
+
+/*
+** This function is called whenever an IOERR or FULL error that requires
+** the pager to transition into the ERROR state may ahve occurred.
+** The first argument is a pointer to the pager structure, the second
+** the error-code about to be returned by a pager API function. The
+** value returned is a copy of the second argument to this function.
+**
+** If the second argument is SQLITE_FULL, SQLITE_IOERR or one of the
+** IOERR sub-codes, the pager enters the ERROR state and the error code
+** is stored in Pager.errCode. While the pager remains in the ERROR state,
+** all major API calls on the Pager will immediately return Pager.errCode.
+**
+** The ERROR state indicates that the contents of the pager-cache
+** cannot be trusted. This state can be cleared by completely discarding
+** the contents of the pager-cache. If a transaction was active when
+** the persistent error occurred, then the rollback journal may need
+** to be replayed to restore the contents of the database file (as if
+** it were a hot-journal).
+*/
+static int pager_error(Pager *pPager, int rc){
+ int rc2 = rc & 0xff;
+ assert( rc==SQLITE_OK || !MEMDB );
+ assert(
+ pPager->errCode==SQLITE_FULL ||
+ pPager->errCode==SQLITE_OK ||
+ (pPager->errCode & 0xff)==SQLITE_IOERR
+ );
+ if( rc2==SQLITE_FULL || rc2==SQLITE_IOERR ){
+ pPager->errCode = rc;
+ pPager->eState = PAGER_ERROR;
+ }
+ return rc;
+}
+
+static int pager_truncate(Pager *pPager, Pgno nPage);
+
+/*
+** This routine ends a transaction. A transaction is usually ended by
+** either a COMMIT or a ROLLBACK operation. This routine may be called
+** after rollback of a hot-journal, or if an error occurs while opening
+** the journal file or writing the very first journal-header of a
+** database transaction.
+**
+** This routine is never called in PAGER_ERROR state. If it is called
+** in PAGER_NONE or PAGER_SHARED state and the lock held is less
+** exclusive than a RESERVED lock, it is a no-op.
+**
+** Otherwise, any active savepoints are released.
+**
+** If the journal file is open, then it is "finalized". Once a journal
+** file has been finalized it is not possible to use it to roll back a
+** transaction. Nor will it be considered to be a hot-journal by this
+** or any other database connection. Exactly how a journal is finalized
+** depends on whether or not the pager is running in exclusive mode and
+** the current journal-mode (Pager.journalMode value), as follows:
+**
+** journalMode==MEMORY
+** Journal file descriptor is simply closed. This destroys an
+** in-memory journal.
+**
+** journalMode==TRUNCATE
+** Journal file is truncated to zero bytes in size.
+**
+** journalMode==PERSIST
+** The first 28 bytes of the journal file are zeroed. This invalidates
+** the first journal header in the file, and hence the entire journal
+** file. An invalid journal file cannot be rolled back.
+**
+** journalMode==DELETE
+** The journal file is closed and deleted using sqlite3OsDelete().
+**
+** If the pager is running in exclusive mode, this method of finalizing
+** the journal file is never used. Instead, if the journalMode is
+** DELETE and the pager is in exclusive mode, the method described under
+** journalMode==PERSIST is used instead.
+**
+** After the journal is finalized, the pager moves to PAGER_READER state.
+** If running in non-exclusive rollback mode, the lock on the file is
+** downgraded to a SHARED_LOCK.
+**
+** SQLITE_OK is returned if no error occurs. If an error occurs during
+** any of the IO operations to finalize the journal file or unlock the
+** database then the IO error code is returned to the user. If the
+** operation to finalize the journal file fails, then the code still
+** tries to unlock the database file if not in exclusive mode. If the
+** unlock operation fails as well, then the first error code related
+** to the first error encountered (the journal finalization one) is
+** returned.
+*/
+static int pager_end_transaction(Pager *pPager, int hasMaster, int bCommit){
+ int rc = SQLITE_OK; /* Error code from journal finalization operation */
+ int rc2 = SQLITE_OK; /* Error code from db file unlock operation */
+
+ /* Do nothing if the pager does not have an open write transaction
+ ** or at least a RESERVED lock. This function may be called when there
+ ** is no write-transaction active but a RESERVED or greater lock is
+ ** held under two circumstances:
+ **
+ ** 1. After a successful hot-journal rollback, it is called with
+ ** eState==PAGER_NONE and eLock==EXCLUSIVE_LOCK.
+ **
+ ** 2. If a connection with locking_mode=exclusive holding an EXCLUSIVE
+ ** lock switches back to locking_mode=normal and then executes a
+ ** read-transaction, this function is called with eState==PAGER_READER
+ ** and eLock==EXCLUSIVE_LOCK when the read-transaction is closed.
+ */
+ assert( assert_pager_state(pPager) );
+ assert( pPager->eState!=PAGER_ERROR );
+ if( pPager->eStateeLockjfd) || pPager->pInJournal==0 );
+ if( isOpen(pPager->jfd) ){
+ assert( !pagerUseWal(pPager) );
+
+ /* Finalize the journal file. */
+ if( sqlite3IsMemJournal(pPager->jfd) ){
+ assert( pPager->journalMode==PAGER_JOURNALMODE_MEMORY );
+ sqlite3OsClose(pPager->jfd);
+ }else if( pPager->journalMode==PAGER_JOURNALMODE_TRUNCATE ){
+ if( pPager->journalOff==0 ){
+ rc = SQLITE_OK;
+ }else{
+ rc = sqlite3OsTruncate(pPager->jfd, 0);
+ }
+ pPager->journalOff = 0;
+ }else if( pPager->journalMode==PAGER_JOURNALMODE_PERSIST
+ || (pPager->exclusiveMode && pPager->journalMode!=PAGER_JOURNALMODE_WAL)
+ ){
+ rc = zeroJournalHdr(pPager, hasMaster);
+ pPager->journalOff = 0;
+ }else{
+ /* This branch may be executed with Pager.journalMode==MEMORY if
+ ** a hot-journal was just rolled back. In this case the journal
+ ** file should be closed and deleted. If this connection writes to
+ ** the database file, it will do so using an in-memory journal.
+ */
+ int bDelete = (!pPager->tempFile && sqlite3JournalExists(pPager->jfd));
+ assert( pPager->journalMode==PAGER_JOURNALMODE_DELETE
+ || pPager->journalMode==PAGER_JOURNALMODE_MEMORY
+ || pPager->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ sqlite3OsClose(pPager->jfd);
+ if( bDelete ){
+ rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+ }
+ }
+ }
+
+#ifdef SQLITE_CHECK_PAGES
+ sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
+ if( pPager->dbSize==0 && sqlite3PcacheRefCount(pPager->pPCache)>0 ){
+ PgHdr *p = pager_lookup(pPager, 1);
+ if( p ){
+ p->pageHash = 0;
+ sqlite3PagerUnrefNotNull(p);
+ }
+ }
+#endif
+
+ sqlite3BitvecDestroy(pPager->pInJournal);
+ pPager->pInJournal = 0;
+ pPager->nRec = 0;
+ sqlite3PcacheCleanAll(pPager->pPCache);
+ sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
+
+ if( pagerUseWal(pPager) ){
+ /* Drop the WAL write-lock, if any. Also, if the connection was in
+ ** locking_mode=exclusive mode but is no longer, drop the EXCLUSIVE
+ ** lock held on the database file.
+ */
+ rc2 = sqlite3WalEndWriteTransaction(pPager->pWal);
+ assert( rc2==SQLITE_OK );
+ }else if( rc==SQLITE_OK && bCommit && pPager->dbFileSize>pPager->dbSize ){
+ /* This branch is taken when committing a transaction in rollback-journal
+ ** mode if the database file on disk is larger than the database image.
+ ** At this point the journal has been finalized and the transaction
+ ** successfully committed, but the EXCLUSIVE lock is still held on the
+ ** file. So it is safe to truncate the database file to its minimum
+ ** required size. */
+ assert( pPager->eLock==EXCLUSIVE_LOCK );
+ rc = pager_truncate(pPager, pPager->dbSize);
+ }
+
+ if( rc==SQLITE_OK && bCommit && isOpen(pPager->fd) ){
+ rc = sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_COMMIT_PHASETWO, 0);
+ if( rc==SQLITE_NOTFOUND ) rc = SQLITE_OK;
+ }
+
+ if( !pPager->exclusiveMode
+ && (!pagerUseWal(pPager) || sqlite3WalExclusiveMode(pPager->pWal, 0))
+ ){
+ rc2 = pagerUnlockDb(pPager, SHARED_LOCK);
+ pPager->changeCountDone = 0;
+ }
+ pPager->eState = PAGER_READER;
+ pPager->setMaster = 0;
+
+ return (rc==SQLITE_OK?rc2:rc);
+}
+
+/*
+** Execute a rollback if a transaction is active and unlock the
+** database file.
+**
+** If the pager has already entered the ERROR state, do not attempt
+** the rollback at this time. Instead, pager_unlock() is called. The
+** call to pager_unlock() will discard all in-memory pages, unlock
+** the database file and move the pager back to OPEN state. If this
+** means that there is a hot-journal left in the file-system, the next
+** connection to obtain a shared lock on the pager (which may be this one)
+** will roll it back.
+**
+** If the pager has not already entered the ERROR state, but an IO or
+** malloc error occurs during a rollback, then this will itself cause
+** the pager to enter the ERROR state. Which will be cleared by the
+** call to pager_unlock(), as described above.
+*/
+static void pagerUnlockAndRollback(Pager *pPager){
+ if( pPager->eState!=PAGER_ERROR && pPager->eState!=PAGER_OPEN ){
+ assert( assert_pager_state(pPager) );
+ if( pPager->eState>=PAGER_WRITER_LOCKED ){
+ sqlite3BeginBenignMalloc();
+ sqlite3PagerRollback(pPager);
+ sqlite3EndBenignMalloc();
+ }else if( !pPager->exclusiveMode ){
+ assert( pPager->eState==PAGER_READER );
+ pager_end_transaction(pPager, 0, 0);
+ }
+ }
+ pager_unlock(pPager);
+}
+
+/*
+** Parameter aData must point to a buffer of pPager->pageSize bytes
+** of data. Compute and return a checksum based ont the contents of the
+** page of data and the current value of pPager->cksumInit.
+**
+** This is not a real checksum. It is really just the sum of the
+** random initial value (pPager->cksumInit) and every 200th byte
+** of the page data, starting with byte offset (pPager->pageSize%200).
+** Each byte is interpreted as an 8-bit unsigned integer.
+**
+** Changing the formula used to compute this checksum results in an
+** incompatible journal file format.
+**
+** If journal corruption occurs due to a power failure, the most likely
+** scenario is that one end or the other of the record will be changed.
+** It is much less likely that the two ends of the journal record will be
+** correct and the middle be corrupt. Thus, this "checksum" scheme,
+** though fast and simple, catches the mostly likely kind of corruption.
+*/
+static u32 pager_cksum(Pager *pPager, const u8 *aData){
+ u32 cksum = pPager->cksumInit; /* Checksum value to return */
+ int i = pPager->pageSize-200; /* Loop counter */
+ while( i>0 ){
+ cksum += aData[i];
+ i -= 200;
+ }
+ return cksum;
+}
+
+/*
+** Report the current page size and number of reserved bytes back
+** to the codec.
+*/
+#ifdef SQLITE_HAS_CODEC
+static void pagerReportSize(Pager *pPager){
+ if( pPager->xCodecSizeChng ){
+ pPager->xCodecSizeChng(pPager->pCodec, pPager->pageSize,
+ (int)pPager->nReserve);
+ }
+}
+#else
+# define pagerReportSize(X) /* No-op if we do not support a codec */
+#endif
+
+/*
+** Read a single page from either the journal file (if isMainJrnl==1) or
+** from the sub-journal (if isMainJrnl==0) and playback that page.
+** The page begins at offset *pOffset into the file. The *pOffset
+** value is increased to the start of the next page in the journal.
+**
+** The main rollback journal uses checksums - the statement journal does
+** not.
+**
+** If the page number of the page record read from the (sub-)journal file
+** is greater than the current value of Pager.dbSize, then playback is
+** skipped and SQLITE_OK is returned.
+**
+** If pDone is not NULL, then it is a record of pages that have already
+** been played back. If the page at *pOffset has already been played back
+** (if the corresponding pDone bit is set) then skip the playback.
+** Make sure the pDone bit corresponding to the *pOffset page is set
+** prior to returning.
+**
+** If the page record is successfully read from the (sub-)journal file
+** and played back, then SQLITE_OK is returned. If an IO error occurs
+** while reading the record from the (sub-)journal file or while writing
+** to the database file, then the IO error code is returned. If data
+** is successfully read from the (sub-)journal file but appears to be
+** corrupted, SQLITE_DONE is returned. Data is considered corrupted in
+** two circumstances:
+**
+** * If the record page-number is illegal (0 or PAGER_MJ_PGNO), or
+** * If the record is being rolled back from the main journal file
+** and the checksum field does not match the record content.
+**
+** Neither of these two scenarios are possible during a savepoint rollback.
+**
+** If this is a savepoint rollback, then memory may have to be dynamically
+** allocated by this function. If this is the case and an allocation fails,
+** SQLITE_NOMEM is returned.
+*/
+static int pager_playback_one_page(
+ Pager *pPager, /* The pager being played back */
+ i64 *pOffset, /* Offset of record to playback */
+ Bitvec *pDone, /* Bitvec of pages already played back */
+ int isMainJrnl, /* 1 -> main journal. 0 -> sub-journal. */
+ int isSavepnt /* True for a savepoint rollback */
+){
+ int rc;
+ PgHdr *pPg; /* An existing page in the cache */
+ Pgno pgno; /* The page number of a page in journal */
+ u32 cksum; /* Checksum used for sanity checking */
+ char *aData; /* Temporary storage for the page */
+ sqlite3_file *jfd; /* The file descriptor for the journal file */
+ int isSynced; /* True if journal page is synced */
+
+ assert( (isMainJrnl&~1)==0 ); /* isMainJrnl is 0 or 1 */
+ assert( (isSavepnt&~1)==0 ); /* isSavepnt is 0 or 1 */
+ assert( isMainJrnl || pDone ); /* pDone always used on sub-journals */
+ assert( isSavepnt || pDone==0 ); /* pDone never used on non-savepoint */
+
+ aData = pPager->pTmpSpace;
+ assert( aData ); /* Temp storage must have already been allocated */
+ assert( pagerUseWal(pPager)==0 || (!isMainJrnl && isSavepnt) );
+
+ /* Either the state is greater than PAGER_WRITER_CACHEMOD (a transaction
+ ** or savepoint rollback done at the request of the caller) or this is
+ ** a hot-journal rollback. If it is a hot-journal rollback, the pager
+ ** is in state OPEN and holds an EXCLUSIVE lock. Hot-journal rollback
+ ** only reads from the main journal, not the sub-journal.
+ */
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD
+ || (pPager->eState==PAGER_OPEN && pPager->eLock==EXCLUSIVE_LOCK)
+ );
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD || isMainJrnl );
+
+ /* Read the page number and page data from the journal or sub-journal
+ ** file. Return an error code to the caller if an IO error occurs.
+ */
+ jfd = isMainJrnl ? pPager->jfd : pPager->sjfd;
+ rc = read32bits(jfd, *pOffset, &pgno);
+ if( rc!=SQLITE_OK ) return rc;
+ rc = sqlite3OsRead(jfd, (u8*)aData, pPager->pageSize, (*pOffset)+4);
+ if( rc!=SQLITE_OK ) return rc;
+ *pOffset += pPager->pageSize + 4 + isMainJrnl*4;
+
+ /* Sanity checking on the page. This is more important that I originally
+ ** thought. If a power failure occurs while the journal is being written,
+ ** it could cause invalid data to be written into the journal. We need to
+ ** detect this invalid data (with high probability) and ignore it.
+ */
+ if( pgno==0 || pgno==PAGER_MJ_PGNO(pPager) ){
+ assert( !isSavepnt );
+ return SQLITE_DONE;
+ }
+ if( pgno>(Pgno)pPager->dbSize || sqlite3BitvecTest(pDone, pgno) ){
+ return SQLITE_OK;
+ }
+ if( isMainJrnl ){
+ rc = read32bits(jfd, (*pOffset)-4, &cksum);
+ if( rc ) return rc;
+ if( !isSavepnt && pager_cksum(pPager, (u8*)aData)!=cksum ){
+ return SQLITE_DONE;
+ }
+ }
+
+ /* If this page has already been played by before during the current
+ ** rollback, then don't bother to play it back again.
+ */
+ if( pDone && (rc = sqlite3BitvecSet(pDone, pgno))!=SQLITE_OK ){
+ return rc;
+ }
+
+ /* When playing back page 1, restore the nReserve setting
+ */
+ if( pgno==1 && pPager->nReserve!=((u8*)aData)[20] ){
+ pPager->nReserve = ((u8*)aData)[20];
+ pagerReportSize(pPager);
+ }
+
+ /* If the pager is in CACHEMOD state, then there must be a copy of this
+ ** page in the pager cache. In this case just update the pager cache,
+ ** not the database file. The page is left marked dirty in this case.
+ **
+ ** An exception to the above rule: If the database is in no-sync mode
+ ** and a page is moved during an incremental vacuum then the page may
+ ** not be in the pager cache. Later: if a malloc() or IO error occurs
+ ** during a Movepage() call, then the page may not be in the cache
+ ** either. So the condition described in the above paragraph is not
+ ** assert()able.
+ **
+ ** If in WRITER_DBMOD, WRITER_FINISHED or OPEN state, then we update the
+ ** pager cache if it exists and the main file. The page is then marked
+ ** not dirty. Since this code is only executed in PAGER_OPEN state for
+ ** a hot-journal rollback, it is guaranteed that the page-cache is empty
+ ** if the pager is in OPEN state.
+ **
+ ** Ticket #1171: The statement journal might contain page content that is
+ ** different from the page content at the start of the transaction.
+ ** This occurs when a page is changed prior to the start of a statement
+ ** then changed again within the statement. When rolling back such a
+ ** statement we must not write to the original database unless we know
+ ** for certain that original page contents are synced into the main rollback
+ ** journal. Otherwise, a power loss might leave modified data in the
+ ** database file without an entry in the rollback journal that can
+ ** restore the database to its original form. Two conditions must be
+ ** met before writing to the database files. (1) the database must be
+ ** locked. (2) we know that the original page content is fully synced
+ ** in the main journal either because the page is not in cache or else
+ ** the page is marked as needSync==0.
+ **
+ ** 2008-04-14: When attempting to vacuum a corrupt database file, it
+ ** is possible to fail a statement on a database that does not yet exist.
+ ** Do not attempt to write if database file has never been opened.
+ */
+ if( pagerUseWal(pPager) ){
+ pPg = 0;
+ }else{
+ pPg = pager_lookup(pPager, pgno);
+ }
+ assert( pPg || !MEMDB );
+ assert( pPager->eState!=PAGER_OPEN || pPg==0 );
+ PAGERTRACE(("PLAYBACK %d page %d hash(%08x) %s\n",
+ PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, (u8*)aData),
+ (isMainJrnl?"main-journal":"sub-journal")
+ ));
+ if( isMainJrnl ){
+ isSynced = pPager->noSync || (*pOffset <= pPager->journalHdr);
+ }else{
+ isSynced = (pPg==0 || 0==(pPg->flags & PGHDR_NEED_SYNC));
+ }
+ if( isOpen(pPager->fd)
+ && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+ && isSynced
+ ){
+ i64 ofst = (pgno-1)*(i64)pPager->pageSize;
+ testcase( !isSavepnt && pPg!=0 && (pPg->flags&PGHDR_NEED_SYNC)!=0 );
+ assert( !pagerUseWal(pPager) );
+ rc = sqlite3OsWrite(pPager->fd, (u8 *)aData, pPager->pageSize, ofst);
+ if( pgno>pPager->dbFileSize ){
+ pPager->dbFileSize = pgno;
+ }
+ if( pPager->pBackup ){
+ CODEC1(pPager, aData, pgno, 3, rc=SQLITE_NOMEM);
+ sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)aData);
+ CODEC2(pPager, aData, pgno, 7, rc=SQLITE_NOMEM, aData);
+ }
+ }else if( !isMainJrnl && pPg==0 ){
+ /* If this is a rollback of a savepoint and data was not written to
+ ** the database and the page is not in-memory, there is a potential
+ ** problem. When the page is next fetched by the b-tree layer, it
+ ** will be read from the database file, which may or may not be
+ ** current.
+ **
+ ** There are a couple of different ways this can happen. All are quite
+ ** obscure. When running in synchronous mode, this can only happen
+ ** if the page is on the free-list at the start of the transaction, then
+ ** populated, then moved using sqlite3PagerMovepage().
+ **
+ ** The solution is to add an in-memory page to the cache containing
+ ** the data just read from the sub-journal. Mark the page as dirty
+ ** and if the pager requires a journal-sync, then mark the page as
+ ** requiring a journal-sync before it is written.
+ */
+ assert( isSavepnt );
+ assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)==0 );
+ pPager->doNotSpill |= SPILLFLAG_ROLLBACK;
+ rc = sqlite3PagerAcquire(pPager, pgno, &pPg, 1);
+ assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)!=0 );
+ pPager->doNotSpill &= ~SPILLFLAG_ROLLBACK;
+ if( rc!=SQLITE_OK ) return rc;
+ pPg->flags &= ~PGHDR_NEED_READ;
+ sqlite3PcacheMakeDirty(pPg);
+ }
+ if( pPg ){
+ /* No page should ever be explicitly rolled back that is in use, except
+ ** for page 1 which is held in use in order to keep the lock on the
+ ** database active. However such a page may be rolled back as a result
+ ** of an internal error resulting in an automatic call to
+ ** sqlite3PagerRollback().
+ */
+ void *pData;
+ pData = pPg->pData;
+ memcpy(pData, (u8*)aData, pPager->pageSize);
+ pPager->xReiniter(pPg);
+ if( isMainJrnl && (!isSavepnt || *pOffset<=pPager->journalHdr) ){
+ /* If the contents of this page were just restored from the main
+ ** journal file, then its content must be as they were when the
+ ** transaction was first opened. In this case we can mark the page
+ ** as clean, since there will be no need to write it out to the
+ ** database.
+ **
+ ** There is one exception to this rule. If the page is being rolled
+ ** back as part of a savepoint (or statement) rollback from an
+ ** unsynced portion of the main journal file, then it is not safe
+ ** to mark the page as clean. This is because marking the page as
+ ** clean will clear the PGHDR_NEED_SYNC flag. Since the page is
+ ** already in the journal file (recorded in Pager.pInJournal) and
+ ** the PGHDR_NEED_SYNC flag is cleared, if the page is written to
+ ** again within this transaction, it will be marked as dirty but
+ ** the PGHDR_NEED_SYNC flag will not be set. It could then potentially
+ ** be written out into the database file before its journal file
+ ** segment is synced. If a crash occurs during or following this,
+ ** database corruption may ensue.
+ */
+ assert( !pagerUseWal(pPager) );
+ sqlite3PcacheMakeClean(pPg);
+ }
+ pager_set_pagehash(pPg);
+
+ /* If this was page 1, then restore the value of Pager.dbFileVers.
+ ** Do this before any decoding. */
+ if( pgno==1 ){
+ memcpy(&pPager->dbFileVers, &((u8*)pData)[24],sizeof(pPager->dbFileVers));
+ }
+
+ /* Decode the page just read from disk */
+ CODEC1(pPager, pData, pPg->pgno, 3, rc=SQLITE_NOMEM);
+ sqlite3PcacheRelease(pPg);
+ }
+ return rc;
+}
+
+/*
+** Parameter zMaster is the name of a master journal file. A single journal
+** file that referred to the master journal file has just been rolled back.
+** This routine checks if it is possible to delete the master journal file,
+** and does so if it is.
+**
+** Argument zMaster may point to Pager.pTmpSpace. So that buffer is not
+** available for use within this function.
+**
+** When a master journal file is created, it is populated with the names
+** of all of its child journals, one after another, formatted as utf-8
+** encoded text. The end of each child journal file is marked with a
+** nul-terminator byte (0x00). i.e. the entire contents of a master journal
+** file for a transaction involving two databases might be:
+**
+** "/home/bill/a.db-journal\x00/home/bill/b.db-journal\x00"
+**
+** A master journal file may only be deleted once all of its child
+** journals have been rolled back.
+**
+** This function reads the contents of the master-journal file into
+** memory and loops through each of the child journal names. For
+** each child journal, it checks if:
+**
+** * if the child journal exists, and if so
+** * if the child journal contains a reference to master journal
+** file zMaster
+**
+** If a child journal can be found that matches both of the criteria
+** above, this function returns without doing anything. Otherwise, if
+** no such child journal can be found, file zMaster is deleted from
+** the file-system using sqlite3OsDelete().
+**
+** If an IO error within this function, an error code is returned. This
+** function allocates memory by calling sqlite3Malloc(). If an allocation
+** fails, SQLITE_NOMEM is returned. Otherwise, if no IO or malloc errors
+** occur, SQLITE_OK is returned.
+**
+** TODO: This function allocates a single block of memory to load
+** the entire contents of the master journal file. This could be
+** a couple of kilobytes or so - potentially larger than the page
+** size.
+*/
+static int pager_delmaster(Pager *pPager, const char *zMaster){
+ sqlite3_vfs *pVfs = pPager->pVfs;
+ int rc; /* Return code */
+ sqlite3_file *pMaster; /* Malloc'd master-journal file descriptor */
+ sqlite3_file *pJournal; /* Malloc'd child-journal file descriptor */
+ char *zMasterJournal = 0; /* Contents of master journal file */
+ i64 nMasterJournal; /* Size of master journal file */
+ char *zJournal; /* Pointer to one journal within MJ file */
+ char *zMasterPtr; /* Space to hold MJ filename from a journal file */
+ int nMasterPtr; /* Amount of space allocated to zMasterPtr[] */
+
+ /* Allocate space for both the pJournal and pMaster file descriptors.
+ ** If successful, open the master journal file for reading.
+ */
+ pMaster = (sqlite3_file *)sqlite3MallocZero(pVfs->szOsFile * 2);
+ pJournal = (sqlite3_file *)(((u8 *)pMaster) + pVfs->szOsFile);
+ if( !pMaster ){
+ rc = SQLITE_NOMEM;
+ }else{
+ const int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MASTER_JOURNAL);
+ rc = sqlite3OsOpen(pVfs, zMaster, pMaster, flags, 0);
+ }
+ if( rc!=SQLITE_OK ) goto delmaster_out;
+
+ /* Load the entire master journal file into space obtained from
+ ** sqlite3_malloc() and pointed to by zMasterJournal. Also obtain
+ ** sufficient space (in zMasterPtr) to hold the names of master
+ ** journal files extracted from regular rollback-journals.
+ */
+ rc = sqlite3OsFileSize(pMaster, &nMasterJournal);
+ if( rc!=SQLITE_OK ) goto delmaster_out;
+ nMasterPtr = pVfs->mxPathname+1;
+ zMasterJournal = sqlite3Malloc((int)nMasterJournal + nMasterPtr + 1);
+ if( !zMasterJournal ){
+ rc = SQLITE_NOMEM;
+ goto delmaster_out;
+ }
+ zMasterPtr = &zMasterJournal[nMasterJournal+1];
+ rc = sqlite3OsRead(pMaster, zMasterJournal, (int)nMasterJournal, 0);
+ if( rc!=SQLITE_OK ) goto delmaster_out;
+ zMasterJournal[nMasterJournal] = 0;
+
+ zJournal = zMasterJournal;
+ while( (zJournal-zMasterJournal)pageSize bytes).
+** If the file on disk is currently larger than nPage pages, then use the VFS
+** xTruncate() method to truncate it.
+**
+** Or, it might might be the case that the file on disk is smaller than
+** nPage pages. Some operating system implementations can get confused if
+** you try to truncate a file to some size that is larger than it
+** currently is, so detect this case and write a single zero byte to
+** the end of the new file instead.
+**
+** If successful, return SQLITE_OK. If an IO error occurs while modifying
+** the database file, return the error code to the caller.
+*/
+static int pager_truncate(Pager *pPager, Pgno nPage){
+ int rc = SQLITE_OK;
+ assert( pPager->eState!=PAGER_ERROR );
+ assert( pPager->eState!=PAGER_READER );
+
+ if( isOpen(pPager->fd)
+ && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+ ){
+ i64 currentSize, newSize;
+ int szPage = pPager->pageSize;
+ assert( pPager->eLock==EXCLUSIVE_LOCK );
+ /* TODO: Is it safe to use Pager.dbFileSize here? */
+ rc = sqlite3OsFileSize(pPager->fd, ¤tSize);
+ newSize = szPage*(i64)nPage;
+ if( rc==SQLITE_OK && currentSize!=newSize ){
+ if( currentSize>newSize ){
+ rc = sqlite3OsTruncate(pPager->fd, newSize);
+ }else if( (currentSize+szPage)<=newSize ){
+ char *pTmp = pPager->pTmpSpace;
+ memset(pTmp, 0, szPage);
+ testcase( (newSize-szPage) == currentSize );
+ testcase( (newSize-szPage) > currentSize );
+ rc = sqlite3OsWrite(pPager->fd, pTmp, szPage, newSize-szPage);
+ }
+ if( rc==SQLITE_OK ){
+ pPager->dbFileSize = nPage;
+ }
+ }
+ }
+ return rc;
+}
+
+/*
+** Return a sanitized version of the sector-size of OS file pFile. The
+** return value is guaranteed to lie between 32 and MAX_SECTOR_SIZE.
+*/
+SQLITE_PRIVATE int sqlite3SectorSize(sqlite3_file *pFile){
+ int iRet = sqlite3OsSectorSize(pFile);
+ if( iRet<32 ){
+ iRet = 512;
+ }else if( iRet>MAX_SECTOR_SIZE ){
+ assert( MAX_SECTOR_SIZE>=512 );
+ iRet = MAX_SECTOR_SIZE;
+ }
+ return iRet;
+}
+
+/*
+** Set the value of the Pager.sectorSize variable for the given
+** pager based on the value returned by the xSectorSize method
+** of the open database file. The sector size will be used used
+** to determine the size and alignment of journal header and
+** master journal pointers within created journal files.
+**
+** For temporary files the effective sector size is always 512 bytes.
+**
+** Otherwise, for non-temporary files, the effective sector size is
+** the value returned by the xSectorSize() method rounded up to 32 if
+** it is less than 32, or rounded down to MAX_SECTOR_SIZE if it
+** is greater than MAX_SECTOR_SIZE.
+**
+** If the file has the SQLITE_IOCAP_POWERSAFE_OVERWRITE property, then set
+** the effective sector size to its minimum value (512). The purpose of
+** pPager->sectorSize is to define the "blast radius" of bytes that
+** might change if a crash occurs while writing to a single byte in
+** that range. But with POWERSAFE_OVERWRITE, the blast radius is zero
+** (that is what POWERSAFE_OVERWRITE means), so we minimize the sector
+** size. For backwards compatibility of the rollback journal file format,
+** we cannot reduce the effective sector size below 512.
+*/
+static void setSectorSize(Pager *pPager){
+ assert( isOpen(pPager->fd) || pPager->tempFile );
+
+ if( pPager->tempFile
+ || (sqlite3OsDeviceCharacteristics(pPager->fd) &
+ SQLITE_IOCAP_POWERSAFE_OVERWRITE)!=0
+ ){
+ /* Sector size doesn't matter for temporary files. Also, the file
+ ** may not have been opened yet, in which case the OsSectorSize()
+ ** call will segfault. */
+ pPager->sectorSize = 512;
+ }else{
+ pPager->sectorSize = sqlite3SectorSize(pPager->fd);
+ }
+}
+
+/*
+** Playback the journal and thus restore the database file to
+** the state it was in before we started making changes.
+**
+** The journal file format is as follows:
+**
+** (1) 8 byte prefix. A copy of aJournalMagic[].
+** (2) 4 byte big-endian integer which is the number of valid page records
+** in the journal. If this value is 0xffffffff, then compute the
+** number of page records from the journal size.
+** (3) 4 byte big-endian integer which is the initial value for the
+** sanity checksum.
+** (4) 4 byte integer which is the number of pages to truncate the
+** database to during a rollback.
+** (5) 4 byte big-endian integer which is the sector size. The header
+** is this many bytes in size.
+** (6) 4 byte big-endian integer which is the page size.
+** (7) zero padding out to the next sector size.
+** (8) Zero or more pages instances, each as follows:
+** + 4 byte page number.
+** + pPager->pageSize bytes of data.
+** + 4 byte checksum
+**
+** When we speak of the journal header, we mean the first 7 items above.
+** Each entry in the journal is an instance of the 8th item.
+**
+** Call the value from the second bullet "nRec". nRec is the number of
+** valid page entries in the journal. In most cases, you can compute the
+** value of nRec from the size of the journal file. But if a power
+** failure occurred while the journal was being written, it could be the
+** case that the size of the journal file had already been increased but
+** the extra entries had not yet made it safely to disk. In such a case,
+** the value of nRec computed from the file size would be too large. For
+** that reason, we always use the nRec value in the header.
+**
+** If the nRec value is 0xffffffff it means that nRec should be computed
+** from the file size. This value is used when the user selects the
+** no-sync option for the journal. A power failure could lead to corruption
+** in this case. But for things like temporary table (which will be
+** deleted when the power is restored) we don't care.
+**
+** If the file opened as the journal file is not a well-formed
+** journal file then all pages up to the first corrupted page are rolled
+** back (or no pages if the journal header is corrupted). The journal file
+** is then deleted and SQLITE_OK returned, just as if no corruption had
+** been encountered.
+**
+** If an I/O or malloc() error occurs, the journal-file is not deleted
+** and an error code is returned.
+**
+** The isHot parameter indicates that we are trying to rollback a journal
+** that might be a hot journal. Or, it could be that the journal is
+** preserved because of JOURNALMODE_PERSIST or JOURNALMODE_TRUNCATE.
+** If the journal really is hot, reset the pager cache prior rolling
+** back any content. If the journal is merely persistent, no reset is
+** needed.
+*/
+static int pager_playback(Pager *pPager, int isHot){
+ sqlite3_vfs *pVfs = pPager->pVfs;
+ i64 szJ; /* Size of the journal file in bytes */
+ u32 nRec; /* Number of Records in the journal */
+ u32 u; /* Unsigned loop counter */
+ Pgno mxPg = 0; /* Size of the original file in pages */
+ int rc; /* Result code of a subroutine */
+ int res = 1; /* Value returned by sqlite3OsAccess() */
+ char *zMaster = 0; /* Name of master journal file if any */
+ int needPagerReset; /* True to reset page prior to first page rollback */
+ int nPlayback = 0; /* Total number of pages restored from journal */
+
+ /* Figure out how many records are in the journal. Abort early if
+ ** the journal is empty.
+ */
+ assert( isOpen(pPager->jfd) );
+ rc = sqlite3OsFileSize(pPager->jfd, &szJ);
+ if( rc!=SQLITE_OK ){
+ goto end_playback;
+ }
+
+ /* Read the master journal name from the journal, if it is present.
+ ** If a master journal file name is specified, but the file is not
+ ** present on disk, then the journal is not hot and does not need to be
+ ** played back.
+ **
+ ** TODO: Technically the following is an error because it assumes that
+ ** buffer Pager.pTmpSpace is (mxPathname+1) bytes or larger. i.e. that
+ ** (pPager->pageSize >= pPager->pVfs->mxPathname+1). Using os_unix.c,
+ ** mxPathname is 512, which is the same as the minimum allowable value
+ ** for pageSize.
+ */
+ zMaster = pPager->pTmpSpace;
+ rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
+ if( rc==SQLITE_OK && zMaster[0] ){
+ rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
+ }
+ zMaster = 0;
+ if( rc!=SQLITE_OK || !res ){
+ goto end_playback;
+ }
+ pPager->journalOff = 0;
+ needPagerReset = isHot;
+
+ /* This loop terminates either when a readJournalHdr() or
+ ** pager_playback_one_page() call returns SQLITE_DONE or an IO error
+ ** occurs.
+ */
+ while( 1 ){
+ /* Read the next journal header from the journal file. If there are
+ ** not enough bytes left in the journal file for a complete header, or
+ ** it is corrupted, then a process must have failed while writing it.
+ ** This indicates nothing more needs to be rolled back.
+ */
+ rc = readJournalHdr(pPager, isHot, szJ, &nRec, &mxPg);
+ if( rc!=SQLITE_OK ){
+ if( rc==SQLITE_DONE ){
+ rc = SQLITE_OK;
+ }
+ goto end_playback;
+ }
+
+ /* If nRec is 0xffffffff, then this journal was created by a process
+ ** working in no-sync mode. This means that the rest of the journal
+ ** file consists of pages, there are no more journal headers. Compute
+ ** the value of nRec based on this assumption.
+ */
+ if( nRec==0xffffffff ){
+ assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) );
+ nRec = (int)((szJ - JOURNAL_HDR_SZ(pPager))/JOURNAL_PG_SZ(pPager));
+ }
+
+ /* If nRec is 0 and this rollback is of a transaction created by this
+ ** process and if this is the final header in the journal, then it means
+ ** that this part of the journal was being filled but has not yet been
+ ** synced to disk. Compute the number of pages based on the remaining
+ ** size of the file.
+ **
+ ** The third term of the test was added to fix ticket #2565.
+ ** When rolling back a hot journal, nRec==0 always means that the next
+ ** chunk of the journal contains zero pages to be rolled back. But
+ ** when doing a ROLLBACK and the nRec==0 chunk is the last chunk in
+ ** the journal, it means that the journal might contain additional
+ ** pages that need to be rolled back and that the number of pages
+ ** should be computed based on the journal file size.
+ */
+ if( nRec==0 && !isHot &&
+ pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff ){
+ nRec = (int)((szJ - pPager->journalOff) / JOURNAL_PG_SZ(pPager));
+ }
+
+ /* If this is the first header read from the journal, truncate the
+ ** database file back to its original size.
+ */
+ if( pPager->journalOff==JOURNAL_HDR_SZ(pPager) ){
+ rc = pager_truncate(pPager, mxPg);
+ if( rc!=SQLITE_OK ){
+ goto end_playback;
+ }
+ pPager->dbSize = mxPg;
+ }
+
+ /* Copy original pages out of the journal and back into the
+ ** database file and/or page cache.
+ */
+ for(u=0; ujournalOff,0,1,0);
+ if( rc==SQLITE_OK ){
+ nPlayback++;
+ }else{
+ if( rc==SQLITE_DONE ){
+ pPager->journalOff = szJ;
+ break;
+ }else if( rc==SQLITE_IOERR_SHORT_READ ){
+ /* If the journal has been truncated, simply stop reading and
+ ** processing the journal. This might happen if the journal was
+ ** not completely written and synced prior to a crash. In that
+ ** case, the database should have never been written in the
+ ** first place so it is OK to simply abandon the rollback. */
+ rc = SQLITE_OK;
+ goto end_playback;
+ }else{
+ /* If we are unable to rollback, quit and return the error
+ ** code. This will cause the pager to enter the error state
+ ** so that no further harm will be done. Perhaps the next
+ ** process to come along will be able to rollback the database.
+ */
+ goto end_playback;
+ }
+ }
+ }
+ }
+ /*NOTREACHED*/
+ assert( 0 );
+
+end_playback:
+ /* Following a rollback, the database file should be back in its original
+ ** state prior to the start of the transaction, so invoke the
+ ** SQLITE_FCNTL_DB_UNCHANGED file-control method to disable the
+ ** assertion that the transaction counter was modified.
+ */
+#ifdef SQLITE_DEBUG
+ if( pPager->fd->pMethods ){
+ sqlite3OsFileControlHint(pPager->fd,SQLITE_FCNTL_DB_UNCHANGED,0);
+ }
+#endif
+
+ /* If this playback is happening automatically as a result of an IO or
+ ** malloc error that occurred after the change-counter was updated but
+ ** before the transaction was committed, then the change-counter
+ ** modification may just have been reverted. If this happens in exclusive
+ ** mode, then subsequent transactions performed by the connection will not
+ ** update the change-counter at all. This may lead to cache inconsistency
+ ** problems for other processes at some point in the future. So, just
+ ** in case this has happened, clear the changeCountDone flag now.
+ */
+ pPager->changeCountDone = pPager->tempFile;
+
+ if( rc==SQLITE_OK ){
+ zMaster = pPager->pTmpSpace;
+ rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
+ testcase( rc!=SQLITE_OK );
+ }
+ if( rc==SQLITE_OK
+ && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+ ){
+ rc = sqlite3PagerSync(pPager, 0);
+ }
+ if( rc==SQLITE_OK ){
+ rc = pager_end_transaction(pPager, zMaster[0]!='\0', 0);
+ testcase( rc!=SQLITE_OK );
+ }
+ if( rc==SQLITE_OK && zMaster[0] && res ){
+ /* If there was a master journal and this routine will return success,
+ ** see if it is possible to delete the master journal.
+ */
+ rc = pager_delmaster(pPager, zMaster);
+ testcase( rc!=SQLITE_OK );
+ }
+ if( isHot && nPlayback ){
+ sqlite3_log(SQLITE_NOTICE_RECOVER_ROLLBACK, "recovered %d pages from %s",
+ nPlayback, pPager->zJournal);
+ }
+
+ /* The Pager.sectorSize variable may have been updated while rolling
+ ** back a journal created by a process with a different sector size
+ ** value. Reset it to the correct value for this process.
+ */
+ setSectorSize(pPager);
+ return rc;
+}
+
+
+/*
+** Read the content for page pPg out of the database file and into
+** pPg->pData. A shared lock or greater must be held on the database
+** file before this function is called.
+**
+** If page 1 is read, then the value of Pager.dbFileVers[] is set to
+** the value read from the database file.
+**
+** If an IO error occurs, then the IO error is returned to the caller.
+** Otherwise, SQLITE_OK is returned.
+*/
+static int readDbPage(PgHdr *pPg, u32 iFrame){
+ Pager *pPager = pPg->pPager; /* Pager object associated with page pPg */
+ Pgno pgno = pPg->pgno; /* Page number to read */
+ int rc = SQLITE_OK; /* Return code */
+ int pgsz = pPager->pageSize; /* Number of bytes to read */
+
+ assert( pPager->eState>=PAGER_READER && !MEMDB );
+ assert( isOpen(pPager->fd) );
+
+#ifndef SQLITE_OMIT_WAL
+ if( iFrame ){
+ /* Try to pull the page from the write-ahead log. */
+ rc = sqlite3WalReadFrame(pPager->pWal, iFrame, pgsz, pPg->pData);
+ }else
+#endif
+ {
+ i64 iOffset = (pgno-1)*(i64)pPager->pageSize;
+ rc = sqlite3OsRead(pPager->fd, pPg->pData, pgsz, iOffset);
+ if( rc==SQLITE_IOERR_SHORT_READ ){
+ rc = SQLITE_OK;
+ }
+ }
+
+ if( pgno==1 ){
+ if( rc ){
+ /* If the read is unsuccessful, set the dbFileVers[] to something
+ ** that will never be a valid file version. dbFileVers[] is a copy
+ ** of bytes 24..39 of the database. Bytes 28..31 should always be
+ ** zero or the size of the database in page. Bytes 32..35 and 35..39
+ ** should be page numbers which are never 0xffffffff. So filling
+ ** pPager->dbFileVers[] with all 0xff bytes should suffice.
+ **
+ ** For an encrypted database, the situation is more complex: bytes
+ ** 24..39 of the database are white noise. But the probability of
+ ** white noising equaling 16 bytes of 0xff is vanishingly small so
+ ** we should still be ok.
+ */
+ memset(pPager->dbFileVers, 0xff, sizeof(pPager->dbFileVers));
+ }else{
+ u8 *dbFileVers = &((u8*)pPg->pData)[24];
+ memcpy(&pPager->dbFileVers, dbFileVers, sizeof(pPager->dbFileVers));
+ }
+ }
+ CODEC1(pPager, pPg->pData, pgno, 3, rc = SQLITE_NOMEM);
+
+ PAGER_INCR(sqlite3_pager_readdb_count);
+ PAGER_INCR(pPager->nRead);
+ IOTRACE(("PGIN %p %d\n", pPager, pgno));
+ PAGERTRACE(("FETCH %d page %d hash(%08x)\n",
+ PAGERID(pPager), pgno, pager_pagehash(pPg)));
+
+ return rc;
+}
+
+/*
+** Update the value of the change-counter at offsets 24 and 92 in
+** the header and the sqlite version number at offset 96.
+**
+** This is an unconditional update. See also the pager_incr_changecounter()
+** routine which only updates the change-counter if the update is actually
+** needed, as determined by the pPager->changeCountDone state variable.
+*/
+static void pager_write_changecounter(PgHdr *pPg){
+ u32 change_counter;
+
+ /* Increment the value just read and write it back to byte 24. */
+ change_counter = sqlite3Get4byte((u8*)pPg->pPager->dbFileVers)+1;
+ put32bits(((char*)pPg->pData)+24, change_counter);
+
+ /* Also store the SQLite version number in bytes 96..99 and in
+ ** bytes 92..95 store the change counter for which the version number
+ ** is valid. */
+ put32bits(((char*)pPg->pData)+92, change_counter);
+ put32bits(((char*)pPg->pData)+96, SQLITE_VERSION_NUMBER);
+}
+
+#ifndef SQLITE_OMIT_WAL
+/*
+** This function is invoked once for each page that has already been
+** written into the log file when a WAL transaction is rolled back.
+** Parameter iPg is the page number of said page. The pCtx argument
+** is actually a pointer to the Pager structure.
+**
+** If page iPg is present in the cache, and has no outstanding references,
+** it is discarded. Otherwise, if there are one or more outstanding
+** references, the page content is reloaded from the database. If the
+** attempt to reload content from the database is required and fails,
+** return an SQLite error code. Otherwise, SQLITE_OK.
+*/
+static int pagerUndoCallback(void *pCtx, Pgno iPg){
+ int rc = SQLITE_OK;
+ Pager *pPager = (Pager *)pCtx;
+ PgHdr *pPg;
+
+ assert( pagerUseWal(pPager) );
+ pPg = sqlite3PagerLookup(pPager, iPg);
+ if( pPg ){
+ if( sqlite3PcachePageRefcount(pPg)==1 ){
+ sqlite3PcacheDrop(pPg);
+ }else{
+ u32 iFrame = 0;
+ rc = sqlite3WalFindFrame(pPager->pWal, pPg->pgno, &iFrame);
+ if( rc==SQLITE_OK ){
+ rc = readDbPage(pPg, iFrame);
+ }
+ if( rc==SQLITE_OK ){
+ pPager->xReiniter(pPg);
+ }
+ sqlite3PagerUnrefNotNull(pPg);
+ }
+ }
+
+ /* Normally, if a transaction is rolled back, any backup processes are
+ ** updated as data is copied out of the rollback journal and into the
+ ** database. This is not generally possible with a WAL database, as
+ ** rollback involves simply truncating the log file. Therefore, if one
+ ** or more frames have already been written to the log (and therefore
+ ** also copied into the backup databases) as part of this transaction,
+ ** the backups must be restarted.
+ */
+ sqlite3BackupRestart(pPager->pBackup);
+
+ return rc;
+}
+
+/*
+** This function is called to rollback a transaction on a WAL database.
+*/
+static int pagerRollbackWal(Pager *pPager){
+ int rc; /* Return Code */
+ PgHdr *pList; /* List of dirty pages to revert */
+
+ /* For all pages in the cache that are currently dirty or have already
+ ** been written (but not committed) to the log file, do one of the
+ ** following:
+ **
+ ** + Discard the cached page (if refcount==0), or
+ ** + Reload page content from the database (if refcount>0).
+ */
+ pPager->dbSize = pPager->dbOrigSize;
+ rc = sqlite3WalUndo(pPager->pWal, pagerUndoCallback, (void *)pPager);
+ pList = sqlite3PcacheDirtyList(pPager->pPCache);
+ while( pList && rc==SQLITE_OK ){
+ PgHdr *pNext = pList->pDirty;
+ rc = pagerUndoCallback((void *)pPager, pList->pgno);
+ pList = pNext;
+ }
+
+ return rc;
+}
+
+/*
+** This function is a wrapper around sqlite3WalFrames(). As well as logging
+** the contents of the list of pages headed by pList (connected by pDirty),
+** this function notifies any active backup processes that the pages have
+** changed.
+**
+** The list of pages passed into this routine is always sorted by page number.
+** Hence, if page 1 appears anywhere on the list, it will be the first page.
+*/
+static int pagerWalFrames(
+ Pager *pPager, /* Pager object */
+ PgHdr *pList, /* List of frames to log */
+ Pgno nTruncate, /* Database size after this commit */
+ int isCommit /* True if this is a commit */
+){
+ int rc; /* Return code */
+ int nList; /* Number of pages in pList */
+#if defined(SQLITE_DEBUG) || defined(SQLITE_CHECK_PAGES)
+ PgHdr *p; /* For looping over pages */
+#endif
+
+ assert( pPager->pWal );
+ assert( pList );
+#ifdef SQLITE_DEBUG
+ /* Verify that the page list is in accending order */
+ for(p=pList; p && p->pDirty; p=p->pDirty){
+ assert( p->pgno < p->pDirty->pgno );
+ }
+#endif
+
+ assert( pList->pDirty==0 || isCommit );
+ if( isCommit ){
+ /* If a WAL transaction is being committed, there is no point in writing
+ ** any pages with page numbers greater than nTruncate into the WAL file.
+ ** They will never be read by any client. So remove them from the pDirty
+ ** list here. */
+ PgHdr *p;
+ PgHdr **ppNext = &pList;
+ nList = 0;
+ for(p=pList; (*ppNext = p)!=0; p=p->pDirty){
+ if( p->pgno<=nTruncate ){
+ ppNext = &p->pDirty;
+ nList++;
+ }
+ }
+ assert( pList );
+ }else{
+ nList = 1;
+ }
+ pPager->aStat[PAGER_STAT_WRITE] += nList;
+
+ if( pList->pgno==1 ) pager_write_changecounter(pList);
+ rc = sqlite3WalFrames(pPager->pWal,
+ pPager->pageSize, pList, nTruncate, isCommit, pPager->walSyncFlags
+ );
+ if( rc==SQLITE_OK && pPager->pBackup ){
+ PgHdr *p;
+ for(p=pList; p; p=p->pDirty){
+ sqlite3BackupUpdate(pPager->pBackup, p->pgno, (u8 *)p->pData);
+ }
+ }
+
+#ifdef SQLITE_CHECK_PAGES
+ pList = sqlite3PcacheDirtyList(pPager->pPCache);
+ for(p=pList; p; p=p->pDirty){
+ pager_set_pagehash(p);
+ }
+#endif
+
+ return rc;
+}
+
+/*
+** Begin a read transaction on the WAL.
+**
+** This routine used to be called "pagerOpenSnapshot()" because it essentially
+** makes a snapshot of the database at the current point in time and preserves
+** that snapshot for use by the reader in spite of concurrently changes by
+** other writers or checkpointers.
+*/
+static int pagerBeginReadTransaction(Pager *pPager){
+ int rc; /* Return code */
+ int changed = 0; /* True if cache must be reset */
+
+ assert( pagerUseWal(pPager) );
+ assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
+
+ /* sqlite3WalEndReadTransaction() was not called for the previous
+ ** transaction in locking_mode=EXCLUSIVE. So call it now. If we
+ ** are in locking_mode=NORMAL and EndRead() was previously called,
+ ** the duplicate call is harmless.
+ */
+ sqlite3WalEndReadTransaction(pPager->pWal);
+
+ rc = sqlite3WalBeginReadTransaction(pPager->pWal, &changed);
+ if( rc!=SQLITE_OK || changed ){
+ pager_reset(pPager);
+ if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
+ }
+
+ return rc;
+}
+#endif
+
+/*
+** This function is called as part of the transition from PAGER_OPEN
+** to PAGER_READER state to determine the size of the database file
+** in pages (assuming the page size currently stored in Pager.pageSize).
+**
+** If no error occurs, SQLITE_OK is returned and the size of the database
+** in pages is stored in *pnPage. Otherwise, an error code (perhaps
+** SQLITE_IOERR_FSTAT) is returned and *pnPage is left unmodified.
+*/
+static int pagerPagecount(Pager *pPager, Pgno *pnPage){
+ Pgno nPage; /* Value to return via *pnPage */
+
+ /* Query the WAL sub-system for the database size. The WalDbsize()
+ ** function returns zero if the WAL is not open (i.e. Pager.pWal==0), or
+ ** if the database size is not available. The database size is not
+ ** available from the WAL sub-system if the log file is empty or
+ ** contains no valid committed transactions.
+ */
+ assert( pPager->eState==PAGER_OPEN );
+ assert( pPager->eLock>=SHARED_LOCK );
+ nPage = sqlite3WalDbsize(pPager->pWal);
+
+ /* If the database size was not available from the WAL sub-system,
+ ** determine it based on the size of the database file. If the size
+ ** of the database file is not an integer multiple of the page-size,
+ ** round down to the nearest page. Except, any file larger than 0
+ ** bytes in size is considered to contain at least one page.
+ */
+ if( nPage==0 ){
+ i64 n = 0; /* Size of db file in bytes */
+ assert( isOpen(pPager->fd) || pPager->tempFile );
+ if( isOpen(pPager->fd) ){
+ int rc = sqlite3OsFileSize(pPager->fd, &n);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ }
+ nPage = (Pgno)((n+pPager->pageSize-1) / pPager->pageSize);
+ }
+
+ /* If the current number of pages in the file is greater than the
+ ** configured maximum pager number, increase the allowed limit so
+ ** that the file can be read.
+ */
+ if( nPage>pPager->mxPgno ){
+ pPager->mxPgno = (Pgno)nPage;
+ }
+
+ *pnPage = nPage;
+ return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_WAL
+/*
+** Check if the *-wal file that corresponds to the database opened by pPager
+** exists if the database is not empy, or verify that the *-wal file does
+** not exist (by deleting it) if the database file is empty.
+**
+** If the database is not empty and the *-wal file exists, open the pager
+** in WAL mode. If the database is empty or if no *-wal file exists and
+** if no error occurs, make sure Pager.journalMode is not set to
+** PAGER_JOURNALMODE_WAL.
+**
+** Return SQLITE_OK or an error code.
+**
+** The caller must hold a SHARED lock on the database file to call this
+** function. Because an EXCLUSIVE lock on the db file is required to delete
+** a WAL on a none-empty database, this ensures there is no race condition
+** between the xAccess() below and an xDelete() being executed by some
+** other connection.
+*/
+static int pagerOpenWalIfPresent(Pager *pPager){
+ int rc = SQLITE_OK;
+ assert( pPager->eState==PAGER_OPEN );
+ assert( pPager->eLock>=SHARED_LOCK );
+
+ if( !pPager->tempFile ){
+ int isWal; /* True if WAL file exists */
+ Pgno nPage; /* Size of the database file */
+
+ rc = pagerPagecount(pPager, &nPage);
+ if( rc ) return rc;
+ if( nPage==0 ){
+ rc = sqlite3OsDelete(pPager->pVfs, pPager->zWal, 0);
+ if( rc==SQLITE_IOERR_DELETE_NOENT ) rc = SQLITE_OK;
+ isWal = 0;
+ }else{
+ rc = sqlite3OsAccess(
+ pPager->pVfs, pPager->zWal, SQLITE_ACCESS_EXISTS, &isWal
+ );
+ }
+ if( rc==SQLITE_OK ){
+ if( isWal ){
+ testcase( sqlite3PcachePagecount(pPager->pPCache)==0 );
+ rc = sqlite3PagerOpenWal(pPager, 0);
+ }else if( pPager->journalMode==PAGER_JOURNALMODE_WAL ){
+ pPager->journalMode = PAGER_JOURNALMODE_DELETE;
+ }
+ }
+ }
+ return rc;
+}
+#endif
+
+/*
+** Playback savepoint pSavepoint. Or, if pSavepoint==NULL, then playback
+** the entire master journal file. The case pSavepoint==NULL occurs when
+** a ROLLBACK TO command is invoked on a SAVEPOINT that is a transaction
+** savepoint.
+**
+** When pSavepoint is not NULL (meaning a non-transaction savepoint is
+** being rolled back), then the rollback consists of up to three stages,
+** performed in the order specified:
+**
+** * Pages are played back from the main journal starting at byte
+** offset PagerSavepoint.iOffset and continuing to
+** PagerSavepoint.iHdrOffset, or to the end of the main journal
+** file if PagerSavepoint.iHdrOffset is zero.
+**
+** * If PagerSavepoint.iHdrOffset is not zero, then pages are played
+** back starting from the journal header immediately following
+** PagerSavepoint.iHdrOffset to the end of the main journal file.
+**
+** * Pages are then played back from the sub-journal file, starting
+** with the PagerSavepoint.iSubRec and continuing to the end of
+** the journal file.
+**
+** Throughout the rollback process, each time a page is rolled back, the
+** corresponding bit is set in a bitvec structure (variable pDone in the
+** implementation below). This is used to ensure that a page is only
+** rolled back the first time it is encountered in either journal.
+**
+** If pSavepoint is NULL, then pages are only played back from the main
+** journal file. There is no need for a bitvec in this case.
+**
+** In either case, before playback commences the Pager.dbSize variable
+** is reset to the value that it held at the start of the savepoint
+** (or transaction). No page with a page-number greater than this value
+** is played back. If one is encountered it is simply skipped.
+*/
+static int pagerPlaybackSavepoint(Pager *pPager, PagerSavepoint *pSavepoint){
+ i64 szJ; /* Effective size of the main journal */
+ i64 iHdrOff; /* End of first segment of main-journal records */
+ int rc = SQLITE_OK; /* Return code */
+ Bitvec *pDone = 0; /* Bitvec to ensure pages played back only once */
+
+ assert( pPager->eState!=PAGER_ERROR );
+ assert( pPager->eState>=PAGER_WRITER_LOCKED );
+
+ /* Allocate a bitvec to use to store the set of pages rolled back */
+ if( pSavepoint ){
+ pDone = sqlite3BitvecCreate(pSavepoint->nOrig);
+ if( !pDone ){
+ return SQLITE_NOMEM;
+ }
+ }
+
+ /* Set the database size back to the value it was before the savepoint
+ ** being reverted was opened.
+ */
+ pPager->dbSize = pSavepoint ? pSavepoint->nOrig : pPager->dbOrigSize;
+ pPager->changeCountDone = pPager->tempFile;
+
+ if( !pSavepoint && pagerUseWal(pPager) ){
+ return pagerRollbackWal(pPager);
+ }
+
+ /* Use pPager->journalOff as the effective size of the main rollback
+ ** journal. The actual file might be larger than this in
+ ** PAGER_JOURNALMODE_TRUNCATE or PAGER_JOURNALMODE_PERSIST. But anything
+ ** past pPager->journalOff is off-limits to us.
+ */
+ szJ = pPager->journalOff;
+ assert( pagerUseWal(pPager)==0 || szJ==0 );
+
+ /* Begin by rolling back records from the main journal starting at
+ ** PagerSavepoint.iOffset and continuing to the next journal header.
+ ** There might be records in the main journal that have a page number
+ ** greater than the current database size (pPager->dbSize) but those
+ ** will be skipped automatically. Pages are added to pDone as they
+ ** are played back.
+ */
+ if( pSavepoint && !pagerUseWal(pPager) ){
+ iHdrOff = pSavepoint->iHdrOffset ? pSavepoint->iHdrOffset : szJ;
+ pPager->journalOff = pSavepoint->iOffset;
+ while( rc==SQLITE_OK && pPager->journalOffjournalOff, pDone, 1, 1);
+ }
+ assert( rc!=SQLITE_DONE );
+ }else{
+ pPager->journalOff = 0;
+ }
+
+ /* Continue rolling back records out of the main journal starting at
+ ** the first journal header seen and continuing until the effective end
+ ** of the main journal file. Continue to skip out-of-range pages and
+ ** continue adding pages rolled back to pDone.
+ */
+ while( rc==SQLITE_OK && pPager->journalOffjournalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff"
+ ** test is related to ticket #2565. See the discussion in the
+ ** pager_playback() function for additional information.
+ */
+ if( nJRec==0
+ && pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff
+ ){
+ nJRec = (u32)((szJ - pPager->journalOff)/JOURNAL_PG_SZ(pPager));
+ }
+ for(ii=0; rc==SQLITE_OK && iijournalOffjournalOff, pDone, 1, 1);
+ }
+ assert( rc!=SQLITE_DONE );
+ }
+ assert( rc!=SQLITE_OK || pPager->journalOff>=szJ );
+
+ /* Finally, rollback pages from the sub-journal. Page that were
+ ** previously rolled back out of the main journal (and are hence in pDone)
+ ** will be skipped. Out-of-range pages are also skipped.
+ */
+ if( pSavepoint ){
+ u32 ii; /* Loop counter */
+ i64 offset = (i64)pSavepoint->iSubRec*(4+pPager->pageSize);
+
+ if( pagerUseWal(pPager) ){
+ rc = sqlite3WalSavepointUndo(pPager->pWal, pSavepoint->aWalData);
+ }
+ for(ii=pSavepoint->iSubRec; rc==SQLITE_OK && iinSubRec; ii++){
+ assert( offset==(i64)ii*(4+pPager->pageSize) );
+ rc = pager_playback_one_page(pPager, &offset, pDone, 0, 1);
+ }
+ assert( rc!=SQLITE_DONE );
+ }
+
+ sqlite3BitvecDestroy(pDone);
+ if( rc==SQLITE_OK ){
+ pPager->journalOff = szJ;
+ }
+
+ return rc;
+}
+
+/*
+** Change the maximum number of in-memory pages that are allowed.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager *pPager, int mxPage){
+ sqlite3PcacheSetCachesize(pPager->pPCache, mxPage);
+}
+
+/*
+** Invoke SQLITE_FCNTL_MMAP_SIZE based on the current value of szMmap.
+*/
+static void pagerFixMaplimit(Pager *pPager){
+#if SQLITE_MAX_MMAP_SIZE>0
+ sqlite3_file *fd = pPager->fd;
+ if( isOpen(fd) && fd->pMethods->iVersion>=3 ){
+ sqlite3_int64 sz;
+ sz = pPager->szMmap;
+ pPager->bUseFetch = (sz>0);
+ sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_MMAP_SIZE, &sz);
+ }
+#endif
+}
+
+/*
+** Change the maximum size of any memory mapping made of the database file.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetMmapLimit(Pager *pPager, sqlite3_int64 szMmap){
+ pPager->szMmap = szMmap;
+ pagerFixMaplimit(pPager);
+}
+
+/*
+** Free as much memory as possible from the pager.
+*/
+SQLITE_PRIVATE void sqlite3PagerShrink(Pager *pPager){
+ sqlite3PcacheShrink(pPager->pPCache);
+}
+
+/*
+** Adjust settings of the pager to those specified in the pgFlags parameter.
+**
+** The "level" in pgFlags & PAGER_SYNCHRONOUS_MASK sets the robustness
+** of the database to damage due to OS crashes or power failures by
+** changing the number of syncs()s when writing the journals.
+** There are three levels:
+**
+** OFF sqlite3OsSync() is never called. This is the default
+** for temporary and transient files.
+**
+** NORMAL The journal is synced once before writes begin on the
+** database. This is normally adequate protection, but
+** it is theoretically possible, though very unlikely,
+** that an inopertune power failure could leave the journal
+** in a state which would cause damage to the database
+** when it is rolled back.
+**
+** FULL The journal is synced twice before writes begin on the
+** database (with some additional information - the nRec field
+** of the journal header - being written in between the two
+** syncs). If we assume that writing a
+** single disk sector is atomic, then this mode provides
+** assurance that the journal will not be corrupted to the
+** point of causing damage to the database during rollback.
+**
+** The above is for a rollback-journal mode. For WAL mode, OFF continues
+** to mean that no syncs ever occur. NORMAL means that the WAL is synced
+** prior to the start of checkpoint and that the database file is synced
+** at the conclusion of the checkpoint if the entire content of the WAL
+** was written back into the database. But no sync operations occur for
+** an ordinary commit in NORMAL mode with WAL. FULL means that the WAL
+** file is synced following each commit operation, in addition to the
+** syncs associated with NORMAL.
+**
+** Do not confuse synchronous=FULL with SQLITE_SYNC_FULL. The
+** SQLITE_SYNC_FULL macro means to use the MacOSX-style full-fsync
+** using fcntl(F_FULLFSYNC). SQLITE_SYNC_NORMAL means to do an
+** ordinary fsync() call. There is no difference between SQLITE_SYNC_FULL
+** and SQLITE_SYNC_NORMAL on platforms other than MacOSX. But the
+** synchronous=FULL versus synchronous=NORMAL setting determines when
+** the xSync primitive is called and is relevant to all platforms.
+**
+** Numeric values associated with these states are OFF==1, NORMAL=2,
+** and FULL=3.
+*/
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+SQLITE_PRIVATE void sqlite3PagerSetFlags(
+ Pager *pPager, /* The pager to set safety level for */
+ unsigned pgFlags /* Various flags */
+){
+ unsigned level = pgFlags & PAGER_SYNCHRONOUS_MASK;
+ assert( level>=1 && level<=3 );
+ pPager->noSync = (level==1 || pPager->tempFile) ?1:0;
+ pPager->fullSync = (level==3 && !pPager->tempFile) ?1:0;
+ if( pPager->noSync ){
+ pPager->syncFlags = 0;
+ pPager->ckptSyncFlags = 0;
+ }else if( pgFlags & PAGER_FULLFSYNC ){
+ pPager->syncFlags = SQLITE_SYNC_FULL;
+ pPager->ckptSyncFlags = SQLITE_SYNC_FULL;
+ }else if( pgFlags & PAGER_CKPT_FULLFSYNC ){
+ pPager->syncFlags = SQLITE_SYNC_NORMAL;
+ pPager->ckptSyncFlags = SQLITE_SYNC_FULL;
+ }else{
+ pPager->syncFlags = SQLITE_SYNC_NORMAL;
+ pPager->ckptSyncFlags = SQLITE_SYNC_NORMAL;
+ }
+ pPager->walSyncFlags = pPager->syncFlags;
+ if( pPager->fullSync ){
+ pPager->walSyncFlags |= WAL_SYNC_TRANSACTIONS;
+ }
+ if( pgFlags & PAGER_CACHESPILL ){
+ pPager->doNotSpill &= ~SPILLFLAG_OFF;
+ }else{
+ pPager->doNotSpill |= SPILLFLAG_OFF;
+ }
+}
+#endif
+
+/*
+** The following global variable is incremented whenever the library
+** attempts to open a temporary file. This information is used for
+** testing and analysis only.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API int sqlite3_opentemp_count = 0;
+#endif
+
+/*
+** Open a temporary file.
+**
+** Write the file descriptor into *pFile. Return SQLITE_OK on success
+** or some other error code if we fail. The OS will automatically
+** delete the temporary file when it is closed.
+**
+** The flags passed to the VFS layer xOpen() call are those specified
+** by parameter vfsFlags ORed with the following:
+**
+** SQLITE_OPEN_READWRITE
+** SQLITE_OPEN_CREATE
+** SQLITE_OPEN_EXCLUSIVE
+** SQLITE_OPEN_DELETEONCLOSE
+*/
+static int pagerOpentemp(
+ Pager *pPager, /* The pager object */
+ sqlite3_file *pFile, /* Write the file descriptor here */
+ int vfsFlags /* Flags passed through to the VFS */
+){
+ int rc; /* Return code */
+
+#ifdef SQLITE_TEST
+ sqlite3_opentemp_count++; /* Used for testing and analysis only */
+#endif
+
+ vfsFlags |= SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE |
+ SQLITE_OPEN_EXCLUSIVE | SQLITE_OPEN_DELETEONCLOSE;
+ rc = sqlite3OsOpen(pPager->pVfs, 0, pFile, vfsFlags, 0);
+ assert( rc!=SQLITE_OK || isOpen(pFile) );
+ return rc;
+}
+
+/*
+** Set the busy handler function.
+**
+** The pager invokes the busy-handler if sqlite3OsLock() returns
+** SQLITE_BUSY when trying to upgrade from no-lock to a SHARED lock,
+** or when trying to upgrade from a RESERVED lock to an EXCLUSIVE
+** lock. It does *not* invoke the busy handler when upgrading from
+** SHARED to RESERVED, or when upgrading from SHARED to EXCLUSIVE
+** (which occurs during hot-journal rollback). Summary:
+**
+** Transition | Invokes xBusyHandler
+** --------------------------------------------------------
+** NO_LOCK -> SHARED_LOCK | Yes
+** SHARED_LOCK -> RESERVED_LOCK | No
+** SHARED_LOCK -> EXCLUSIVE_LOCK | No
+** RESERVED_LOCK -> EXCLUSIVE_LOCK | Yes
+**
+** If the busy-handler callback returns non-zero, the lock is
+** retried. If it returns zero, then the SQLITE_BUSY error is
+** returned to the caller of the pager API function.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(
+ Pager *pPager, /* Pager object */
+ int (*xBusyHandler)(void *), /* Pointer to busy-handler function */
+ void *pBusyHandlerArg /* Argument to pass to xBusyHandler */
+){
+ pPager->xBusyHandler = xBusyHandler;
+ pPager->pBusyHandlerArg = pBusyHandlerArg;
+
+ if( isOpen(pPager->fd) ){
+ void **ap = (void **)&pPager->xBusyHandler;
+ assert( ((int(*)(void *))(ap[0]))==xBusyHandler );
+ assert( ap[1]==pBusyHandlerArg );
+ sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_BUSYHANDLER, (void *)ap);
+ }
+}
+
+/*
+** Change the page size used by the Pager object. The new page size
+** is passed in *pPageSize.
+**
+** If the pager is in the error state when this function is called, it
+** is a no-op. The value returned is the error state error code (i.e.
+** one of SQLITE_IOERR, an SQLITE_IOERR_xxx sub-code or SQLITE_FULL).
+**
+** Otherwise, if all of the following are true:
+**
+** * the new page size (value of *pPageSize) is valid (a power
+** of two between 512 and SQLITE_MAX_PAGE_SIZE, inclusive), and
+**
+** * there are no outstanding page references, and
+**
+** * the database is either not an in-memory database or it is
+** an in-memory database that currently consists of zero pages.
+**
+** then the pager object page size is set to *pPageSize.
+**
+** If the page size is changed, then this function uses sqlite3PagerMalloc()
+** to obtain a new Pager.pTmpSpace buffer. If this allocation attempt
+** fails, SQLITE_NOMEM is returned and the page size remains unchanged.
+** In all other cases, SQLITE_OK is returned.
+**
+** If the page size is not changed, either because one of the enumerated
+** conditions above is not true, the pager was in error state when this
+** function was called, or because the memory allocation attempt failed,
+** then *pPageSize is set to the old, retained page size before returning.
+*/
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u32 *pPageSize, int nReserve){
+ int rc = SQLITE_OK;
+
+ /* It is not possible to do a full assert_pager_state() here, as this
+ ** function may be called from within PagerOpen(), before the state
+ ** of the Pager object is internally consistent.
+ **
+ ** At one point this function returned an error if the pager was in
+ ** PAGER_ERROR state. But since PAGER_ERROR state guarantees that
+ ** there is at least one outstanding page reference, this function
+ ** is a no-op for that case anyhow.
+ */
+
+ u32 pageSize = *pPageSize;
+ assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
+ if( (pPager->memDb==0 || pPager->dbSize==0)
+ && sqlite3PcacheRefCount(pPager->pPCache)==0
+ && pageSize && pageSize!=(u32)pPager->pageSize
+ ){
+ char *pNew = NULL; /* New temp space */
+ i64 nByte = 0;
+
+ if( pPager->eState>PAGER_OPEN && isOpen(pPager->fd) ){
+ rc = sqlite3OsFileSize(pPager->fd, &nByte);
+ }
+ if( rc==SQLITE_OK ){
+ pNew = (char *)sqlite3PageMalloc(pageSize);
+ if( !pNew ) rc = SQLITE_NOMEM;
+ }
+
+ if( rc==SQLITE_OK ){
+ pager_reset(pPager);
+ pPager->dbSize = (Pgno)((nByte+pageSize-1)/pageSize);
+ pPager->pageSize = pageSize;
+ sqlite3PageFree(pPager->pTmpSpace);
+ pPager->pTmpSpace = pNew;
+ sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
+ }
+ }
+
+ *pPageSize = pPager->pageSize;
+ if( rc==SQLITE_OK ){
+ if( nReserve<0 ) nReserve = pPager->nReserve;
+ assert( nReserve>=0 && nReserve<1000 );
+ pPager->nReserve = (i16)nReserve;
+ pagerReportSize(pPager);
+ pagerFixMaplimit(pPager);
+ }
+ return rc;
+}
+
+/*
+** Return a pointer to the "temporary page" buffer held internally
+** by the pager. This is a buffer that is big enough to hold the
+** entire content of a database page. This buffer is used internally
+** during rollback and will be overwritten whenever a rollback
+** occurs. But other modules are free to use it too, as long as
+** no rollbacks are happening.
+*/
+SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager *pPager){
+ return pPager->pTmpSpace;
+}
+
+/*
+** Attempt to set the maximum database page count if mxPage is positive.
+** Make no changes if mxPage is zero or negative. And never reduce the
+** maximum page count below the current size of the database.
+**
+** Regardless of mxPage, return the current maximum page count.
+*/
+SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager *pPager, int mxPage){
+ if( mxPage>0 ){
+ pPager->mxPgno = mxPage;
+ }
+ assert( pPager->eState!=PAGER_OPEN ); /* Called only by OP_MaxPgcnt */
+ assert( pPager->mxPgno>=pPager->dbSize ); /* OP_MaxPgcnt enforces this */
+ return pPager->mxPgno;
+}
+
+/*
+** The following set of routines are used to disable the simulated
+** I/O error mechanism. These routines are used to avoid simulated
+** errors in places where we do not care about errors.
+**
+** Unless -DSQLITE_TEST=1 is used, these routines are all no-ops
+** and generate no code.
+*/
+#ifdef SQLITE_TEST
+SQLITE_API extern int sqlite3_io_error_pending;
+SQLITE_API extern int sqlite3_io_error_hit;
+static int saved_cnt;
+void disable_simulated_io_errors(void){
+ saved_cnt = sqlite3_io_error_pending;
+ sqlite3_io_error_pending = -1;
+}
+void enable_simulated_io_errors(void){
+ sqlite3_io_error_pending = saved_cnt;
+}
+#else
+# define disable_simulated_io_errors()
+# define enable_simulated_io_errors()
+#endif
+
+/*
+** Read the first N bytes from the beginning of the file into memory
+** that pDest points to.
+**
+** If the pager was opened on a transient file (zFilename==""), or
+** opened on a file less than N bytes in size, the output buffer is
+** zeroed and SQLITE_OK returned. The rationale for this is that this
+** function is used to read database headers, and a new transient or
+** zero sized database has a header than consists entirely of zeroes.
+**
+** If any IO error apart from SQLITE_IOERR_SHORT_READ is encountered,
+** the error code is returned to the caller and the contents of the
+** output buffer undefined.
+*/
+SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager *pPager, int N, unsigned char *pDest){
+ int rc = SQLITE_OK;
+ memset(pDest, 0, N);
+ assert( isOpen(pPager->fd) || pPager->tempFile );
+
+ /* This routine is only called by btree immediately after creating
+ ** the Pager object. There has not been an opportunity to transition
+ ** to WAL mode yet.
+ */
+ assert( !pagerUseWal(pPager) );
+
+ if( isOpen(pPager->fd) ){
+ IOTRACE(("DBHDR %p 0 %d\n", pPager, N))
+ rc = sqlite3OsRead(pPager->fd, pDest, N, 0);
+ if( rc==SQLITE_IOERR_SHORT_READ ){
+ rc = SQLITE_OK;
+ }
+ }
+ return rc;
+}
+
+/*
+** This function may only be called when a read-transaction is open on
+** the pager. It returns the total number of pages in the database.
+**
+** However, if the file is between 1 and bytes in size, then
+** this is considered a 1 page file.
+*/
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager *pPager, int *pnPage){
+ assert( pPager->eState>=PAGER_READER );
+ assert( pPager->eState!=PAGER_WRITER_FINISHED );
+ *pnPage = (int)pPager->dbSize;
+}
+
+
+/*
+** Try to obtain a lock of type locktype on the database file. If
+** a similar or greater lock is already held, this function is a no-op
+** (returning SQLITE_OK immediately).
+**
+** Otherwise, attempt to obtain the lock using sqlite3OsLock(). Invoke
+** the busy callback if the lock is currently not available. Repeat
+** until the busy callback returns false or until the attempt to
+** obtain the lock succeeds.
+**
+** Return SQLITE_OK on success and an error code if we cannot obtain
+** the lock. If the lock is obtained successfully, set the Pager.state
+** variable to locktype before returning.
+*/
+static int pager_wait_on_lock(Pager *pPager, int locktype){
+ int rc; /* Return code */
+
+ /* Check that this is either a no-op (because the requested lock is
+ ** already held, or one of the transistions that the busy-handler
+ ** may be invoked during, according to the comment above
+ ** sqlite3PagerSetBusyhandler().
+ */
+ assert( (pPager->eLock>=locktype)
+ || (pPager->eLock==NO_LOCK && locktype==SHARED_LOCK)
+ || (pPager->eLock==RESERVED_LOCK && locktype==EXCLUSIVE_LOCK)
+ );
+
+ do {
+ rc = pagerLockDb(pPager, locktype);
+ }while( rc==SQLITE_BUSY && pPager->xBusyHandler(pPager->pBusyHandlerArg) );
+ return rc;
+}
+
+/*
+** Function assertTruncateConstraint(pPager) checks that one of the
+** following is true for all dirty pages currently in the page-cache:
+**
+** a) The page number is less than or equal to the size of the
+** current database image, in pages, OR
+**
+** b) if the page content were written at this time, it would not
+** be necessary to write the current content out to the sub-journal
+** (as determined by function subjRequiresPage()).
+**
+** If the condition asserted by this function were not true, and the
+** dirty page were to be discarded from the cache via the pagerStress()
+** routine, pagerStress() would not write the current page content to
+** the database file. If a savepoint transaction were rolled back after
+** this happened, the correct behavior would be to restore the current
+** content of the page. However, since this content is not present in either
+** the database file or the portion of the rollback journal and
+** sub-journal rolled back the content could not be restored and the
+** database image would become corrupt. It is therefore fortunate that
+** this circumstance cannot arise.
+*/
+#if defined(SQLITE_DEBUG)
+static void assertTruncateConstraintCb(PgHdr *pPg){
+ assert( pPg->flags&PGHDR_DIRTY );
+ assert( !subjRequiresPage(pPg) || pPg->pgno<=pPg->pPager->dbSize );
+}
+static void assertTruncateConstraint(Pager *pPager){
+ sqlite3PcacheIterateDirty(pPager->pPCache, assertTruncateConstraintCb);
+}
+#else
+# define assertTruncateConstraint(pPager)
+#endif
+
+/*
+** Truncate the in-memory database file image to nPage pages. This
+** function does not actually modify the database file on disk. It
+** just sets the internal state of the pager object so that the
+** truncation will be done when the current transaction is committed.
+**
+** This function is only called right before committing a transaction.
+** Once this function has been called, the transaction must either be
+** rolled back or committed. It is not safe to call this function and
+** then continue writing to the database.
+*/
+SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager *pPager, Pgno nPage){
+ assert( pPager->dbSize>=nPage );
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
+ pPager->dbSize = nPage;
+
+ /* At one point the code here called assertTruncateConstraint() to
+ ** ensure that all pages being truncated away by this operation are,
+ ** if one or more savepoints are open, present in the savepoint
+ ** journal so that they can be restored if the savepoint is rolled
+ ** back. This is no longer necessary as this function is now only
+ ** called right before committing a transaction. So although the
+ ** Pager object may still have open savepoints (Pager.nSavepoint!=0),
+ ** they cannot be rolled back. So the assertTruncateConstraint() call
+ ** is no longer correct. */
+}
+
+
+/*
+** This function is called before attempting a hot-journal rollback. It
+** syncs the journal file to disk, then sets pPager->journalHdr to the
+** size of the journal file so that the pager_playback() routine knows
+** that the entire journal file has been synced.
+**
+** Syncing a hot-journal to disk before attempting to roll it back ensures
+** that if a power-failure occurs during the rollback, the process that
+** attempts rollback following system recovery sees the same journal
+** content as this process.
+**
+** If everything goes as planned, SQLITE_OK is returned. Otherwise,
+** an SQLite error code.
+*/
+static int pagerSyncHotJournal(Pager *pPager){
+ int rc = SQLITE_OK;
+ if( !pPager->noSync ){
+ rc = sqlite3OsSync(pPager->jfd, SQLITE_SYNC_NORMAL);
+ }
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsFileSize(pPager->jfd, &pPager->journalHdr);
+ }
+ return rc;
+}
+
+/*
+** Obtain a reference to a memory mapped page object for page number pgno.
+** The new object will use the pointer pData, obtained from xFetch().
+** If successful, set *ppPage to point to the new page reference
+** and return SQLITE_OK. Otherwise, return an SQLite error code and set
+** *ppPage to zero.
+**
+** Page references obtained by calling this function should be released
+** by calling pagerReleaseMapPage().
+*/
+static int pagerAcquireMapPage(
+ Pager *pPager, /* Pager object */
+ Pgno pgno, /* Page number */
+ void *pData, /* xFetch()'d data for this page */
+ PgHdr **ppPage /* OUT: Acquired page object */
+){
+ PgHdr *p; /* Memory mapped page to return */
+
+ if( pPager->pMmapFreelist ){
+ *ppPage = p = pPager->pMmapFreelist;
+ pPager->pMmapFreelist = p->pDirty;
+ p->pDirty = 0;
+ memset(p->pExtra, 0, pPager->nExtra);
+ }else{
+ *ppPage = p = (PgHdr *)sqlite3MallocZero(sizeof(PgHdr) + pPager->nExtra);
+ if( p==0 ){
+ sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1) * pPager->pageSize, pData);
+ return SQLITE_NOMEM;
+ }
+ p->pExtra = (void *)&p[1];
+ p->flags = PGHDR_MMAP;
+ p->nRef = 1;
+ p->pPager = pPager;
+ }
+
+ assert( p->pExtra==(void *)&p[1] );
+ assert( p->pPage==0 );
+ assert( p->flags==PGHDR_MMAP );
+ assert( p->pPager==pPager );
+ assert( p->nRef==1 );
+
+ p->pgno = pgno;
+ p->pData = pData;
+ pPager->nMmapOut++;
+
+ return SQLITE_OK;
+}
+
+/*
+** Release a reference to page pPg. pPg must have been returned by an
+** earlier call to pagerAcquireMapPage().
+*/
+static void pagerReleaseMapPage(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ pPager->nMmapOut--;
+ pPg->pDirty = pPager->pMmapFreelist;
+ pPager->pMmapFreelist = pPg;
+
+ assert( pPager->fd->pMethods->iVersion>=3 );
+ sqlite3OsUnfetch(pPager->fd, (i64)(pPg->pgno-1)*pPager->pageSize, pPg->pData);
+}
+
+/*
+** Free all PgHdr objects stored in the Pager.pMmapFreelist list.
+*/
+static void pagerFreeMapHdrs(Pager *pPager){
+ PgHdr *p;
+ PgHdr *pNext;
+ for(p=pPager->pMmapFreelist; p; p=pNext){
+ pNext = p->pDirty;
+ sqlite3_free(p);
+ }
+}
+
+
+/*
+** Shutdown the page cache. Free all memory and close all files.
+**
+** If a transaction was in progress when this routine is called, that
+** transaction is rolled back. All outstanding pages are invalidated
+** and their memory is freed. Any attempt to use a page associated
+** with this page cache after this function returns will likely
+** result in a coredump.
+**
+** This function always succeeds. If a transaction is active an attempt
+** is made to roll it back. If an error occurs during the rollback
+** a hot journal may be left in the filesystem but no error is returned
+** to the caller.
+*/
+SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager){
+ u8 *pTmp = (u8 *)pPager->pTmpSpace;
+
+ assert( assert_pager_state(pPager) );
+ disable_simulated_io_errors();
+ sqlite3BeginBenignMalloc();
+ pagerFreeMapHdrs(pPager);
+ /* pPager->errCode = 0; */
+ pPager->exclusiveMode = 0;
+#ifndef SQLITE_OMIT_WAL
+ sqlite3WalClose(pPager->pWal, pPager->ckptSyncFlags, pPager->pageSize, pTmp);
+ pPager->pWal = 0;
+#endif
+ pager_reset(pPager);
+ if( MEMDB ){
+ pager_unlock(pPager);
+ }else{
+ /* If it is open, sync the journal file before calling UnlockAndRollback.
+ ** If this is not done, then an unsynced portion of the open journal
+ ** file may be played back into the database. If a power failure occurs
+ ** while this is happening, the database could become corrupt.
+ **
+ ** If an error occurs while trying to sync the journal, shift the pager
+ ** into the ERROR state. This causes UnlockAndRollback to unlock the
+ ** database and close the journal file without attempting to roll it
+ ** back or finalize it. The next database user will have to do hot-journal
+ ** rollback before accessing the database file.
+ */
+ if( isOpen(pPager->jfd) ){
+ pager_error(pPager, pagerSyncHotJournal(pPager));
+ }
+ pagerUnlockAndRollback(pPager);
+ }
+ sqlite3EndBenignMalloc();
+ enable_simulated_io_errors();
+ PAGERTRACE(("CLOSE %d\n", PAGERID(pPager)));
+ IOTRACE(("CLOSE %p\n", pPager))
+ sqlite3OsClose(pPager->jfd);
+ sqlite3OsClose(pPager->fd);
+ sqlite3PageFree(pTmp);
+ sqlite3PcacheClose(pPager->pPCache);
+
+#ifdef SQLITE_HAS_CODEC
+ if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
+#endif
+
+ assert( !pPager->aSavepoint && !pPager->pInJournal );
+ assert( !isOpen(pPager->jfd) && !isOpen(pPager->sjfd) );
+
+ sqlite3_free(pPager);
+ return SQLITE_OK;
+}
+
+#if !defined(NDEBUG) || defined(SQLITE_TEST)
+/*
+** Return the page number for page pPg.
+*/
+SQLITE_PRIVATE Pgno sqlite3PagerPagenumber(DbPage *pPg){
+ return pPg->pgno;
+}
+#endif
+
+/*
+** Increment the reference count for page pPg.
+*/
+SQLITE_PRIVATE void sqlite3PagerRef(DbPage *pPg){
+ sqlite3PcacheRef(pPg);
+}
+
+/*
+** Sync the journal. In other words, make sure all the pages that have
+** been written to the journal have actually reached the surface of the
+** disk and can be restored in the event of a hot-journal rollback.
+**
+** If the Pager.noSync flag is set, then this function is a no-op.
+** Otherwise, the actions required depend on the journal-mode and the
+** device characteristics of the file-system, as follows:
+**
+** * If the journal file is an in-memory journal file, no action need
+** be taken.
+**
+** * Otherwise, if the device does not support the SAFE_APPEND property,
+** then the nRec field of the most recently written journal header
+** is updated to contain the number of journal records that have
+** been written following it. If the pager is operating in full-sync
+** mode, then the journal file is synced before this field is updated.
+**
+** * If the device does not support the SEQUENTIAL property, then
+** journal file is synced.
+**
+** Or, in pseudo-code:
+**
+** if( NOT ){
+** if( NOT SAFE_APPEND ){
+** if( ) xSync();
+**
+** }
+** if( NOT SEQUENTIAL ) xSync();
+** }
+**
+** If successful, this routine clears the PGHDR_NEED_SYNC flag of every
+** page currently held in memory before returning SQLITE_OK. If an IO
+** error is encountered, then the IO error code is returned to the caller.
+*/
+static int syncJournal(Pager *pPager, int newHdr){
+ int rc; /* Return code */
+
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+ assert( !pagerUseWal(pPager) );
+
+ rc = sqlite3PagerExclusiveLock(pPager);
+ if( rc!=SQLITE_OK ) return rc;
+
+ if( !pPager->noSync ){
+ assert( !pPager->tempFile );
+ if( isOpen(pPager->jfd) && pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
+ const int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
+ assert( isOpen(pPager->jfd) );
+
+ if( 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
+ /* This block deals with an obscure problem. If the last connection
+ ** that wrote to this database was operating in persistent-journal
+ ** mode, then the journal file may at this point actually be larger
+ ** than Pager.journalOff bytes. If the next thing in the journal
+ ** file happens to be a journal-header (written as part of the
+ ** previous connection's transaction), and a crash or power-failure
+ ** occurs after nRec is updated but before this connection writes
+ ** anything else to the journal file (or commits/rolls back its
+ ** transaction), then SQLite may become confused when doing the
+ ** hot-journal rollback following recovery. It may roll back all
+ ** of this connections data, then proceed to rolling back the old,
+ ** out-of-date data that follows it. Database corruption.
+ **
+ ** To work around this, if the journal file does appear to contain
+ ** a valid header following Pager.journalOff, then write a 0x00
+ ** byte to the start of it to prevent it from being recognized.
+ **
+ ** Variable iNextHdrOffset is set to the offset at which this
+ ** problematic header will occur, if it exists. aMagic is used
+ ** as a temporary buffer to inspect the first couple of bytes of
+ ** the potential journal header.
+ */
+ i64 iNextHdrOffset;
+ u8 aMagic[8];
+ u8 zHeader[sizeof(aJournalMagic)+4];
+
+ memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
+ put32bits(&zHeader[sizeof(aJournalMagic)], pPager->nRec);
+
+ iNextHdrOffset = journalHdrOffset(pPager);
+ rc = sqlite3OsRead(pPager->jfd, aMagic, 8, iNextHdrOffset);
+ if( rc==SQLITE_OK && 0==memcmp(aMagic, aJournalMagic, 8) ){
+ static const u8 zerobyte = 0;
+ rc = sqlite3OsWrite(pPager->jfd, &zerobyte, 1, iNextHdrOffset);
+ }
+ if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
+ return rc;
+ }
+
+ /* Write the nRec value into the journal file header. If in
+ ** full-synchronous mode, sync the journal first. This ensures that
+ ** all data has really hit the disk before nRec is updated to mark
+ ** it as a candidate for rollback.
+ **
+ ** This is not required if the persistent media supports the
+ ** SAFE_APPEND property. Because in this case it is not possible
+ ** for garbage data to be appended to the file, the nRec field
+ ** is populated with 0xFFFFFFFF when the journal header is written
+ ** and never needs to be updated.
+ */
+ if( pPager->fullSync && 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
+ PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
+ IOTRACE(("JSYNC %p\n", pPager))
+ rc = sqlite3OsSync(pPager->jfd, pPager->syncFlags);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ IOTRACE(("JHDR %p %lld\n", pPager, pPager->journalHdr));
+ rc = sqlite3OsWrite(
+ pPager->jfd, zHeader, sizeof(zHeader), pPager->journalHdr
+ );
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ if( 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
+ PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
+ IOTRACE(("JSYNC %p\n", pPager))
+ rc = sqlite3OsSync(pPager->jfd, pPager->syncFlags|
+ (pPager->syncFlags==SQLITE_SYNC_FULL?SQLITE_SYNC_DATAONLY:0)
+ );
+ if( rc!=SQLITE_OK ) return rc;
+ }
+
+ pPager->journalHdr = pPager->journalOff;
+ if( newHdr && 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
+ pPager->nRec = 0;
+ rc = writeJournalHdr(pPager);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ }else{
+ pPager->journalHdr = pPager->journalOff;
+ }
+ }
+
+ /* Unless the pager is in noSync mode, the journal file was just
+ ** successfully synced. Either way, clear the PGHDR_NEED_SYNC flag on
+ ** all pages.
+ */
+ sqlite3PcacheClearSyncFlags(pPager->pPCache);
+ pPager->eState = PAGER_WRITER_DBMOD;
+ assert( assert_pager_state(pPager) );
+ return SQLITE_OK;
+}
+
+/*
+** The argument is the first in a linked list of dirty pages connected
+** by the PgHdr.pDirty pointer. This function writes each one of the
+** in-memory pages in the list to the database file. The argument may
+** be NULL, representing an empty list. In this case this function is
+** a no-op.
+**
+** The pager must hold at least a RESERVED lock when this function
+** is called. Before writing anything to the database file, this lock
+** is upgraded to an EXCLUSIVE lock. If the lock cannot be obtained,
+** SQLITE_BUSY is returned and no data is written to the database file.
+**
+** If the pager is a temp-file pager and the actual file-system file
+** is not yet open, it is created and opened before any data is
+** written out.
+**
+** Once the lock has been upgraded and, if necessary, the file opened,
+** the pages are written out to the database file in list order. Writing
+** a page is skipped if it meets either of the following criteria:
+**
+** * The page number is greater than Pager.dbSize, or
+** * The PGHDR_DONT_WRITE flag is set on the page.
+**
+** If writing out a page causes the database file to grow, Pager.dbFileSize
+** is updated accordingly. If page 1 is written out, then the value cached
+** in Pager.dbFileVers[] is updated to match the new value stored in
+** the database file.
+**
+** If everything is successful, SQLITE_OK is returned. If an IO error
+** occurs, an IO error code is returned. Or, if the EXCLUSIVE lock cannot
+** be obtained, SQLITE_BUSY is returned.
+*/
+static int pager_write_pagelist(Pager *pPager, PgHdr *pList){
+ int rc = SQLITE_OK; /* Return code */
+
+ /* This function is only called for rollback pagers in WRITER_DBMOD state. */
+ assert( !pagerUseWal(pPager) );
+ assert( pPager->eState==PAGER_WRITER_DBMOD );
+ assert( pPager->eLock==EXCLUSIVE_LOCK );
+
+ /* If the file is a temp-file has not yet been opened, open it now. It
+ ** is not possible for rc to be other than SQLITE_OK if this branch
+ ** is taken, as pager_wait_on_lock() is a no-op for temp-files.
+ */
+ if( !isOpen(pPager->fd) ){
+ assert( pPager->tempFile && rc==SQLITE_OK );
+ rc = pagerOpentemp(pPager, pPager->fd, pPager->vfsFlags);
+ }
+
+ /* Before the first write, give the VFS a hint of what the final
+ ** file size will be.
+ */
+ assert( rc!=SQLITE_OK || isOpen(pPager->fd) );
+ if( rc==SQLITE_OK
+ && pPager->dbHintSizedbSize
+ && (pList->pDirty || pList->pgno>pPager->dbHintSize)
+ ){
+ sqlite3_int64 szFile = pPager->pageSize * (sqlite3_int64)pPager->dbSize;
+ sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_SIZE_HINT, &szFile);
+ pPager->dbHintSize = pPager->dbSize;
+ }
+
+ while( rc==SQLITE_OK && pList ){
+ Pgno pgno = pList->pgno;
+
+ /* If there are dirty pages in the page cache with page numbers greater
+ ** than Pager.dbSize, this means sqlite3PagerTruncateImage() was called to
+ ** make the file smaller (presumably by auto-vacuum code). Do not write
+ ** any such pages to the file.
+ **
+ ** Also, do not write out any page that has the PGHDR_DONT_WRITE flag
+ ** set (set by sqlite3PagerDontWrite()).
+ */
+ if( pgno<=pPager->dbSize && 0==(pList->flags&PGHDR_DONT_WRITE) ){
+ i64 offset = (pgno-1)*(i64)pPager->pageSize; /* Offset to write */
+ char *pData; /* Data to write */
+
+ assert( (pList->flags&PGHDR_NEED_SYNC)==0 );
+ if( pList->pgno==1 ) pager_write_changecounter(pList);
+
+ /* Encode the database */
+ CODEC2(pPager, pList->pData, pgno, 6, return SQLITE_NOMEM, pData);
+
+ /* Write out the page data. */
+ rc = sqlite3OsWrite(pPager->fd, pData, pPager->pageSize, offset);
+
+ /* If page 1 was just written, update Pager.dbFileVers to match
+ ** the value now stored in the database file. If writing this
+ ** page caused the database file to grow, update dbFileSize.
+ */
+ if( pgno==1 ){
+ memcpy(&pPager->dbFileVers, &pData[24], sizeof(pPager->dbFileVers));
+ }
+ if( pgno>pPager->dbFileSize ){
+ pPager->dbFileSize = pgno;
+ }
+ pPager->aStat[PAGER_STAT_WRITE]++;
+
+ /* Update any backup objects copying the contents of this pager. */
+ sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)pList->pData);
+
+ PAGERTRACE(("STORE %d page %d hash(%08x)\n",
+ PAGERID(pPager), pgno, pager_pagehash(pList)));
+ IOTRACE(("PGOUT %p %d\n", pPager, pgno));
+ PAGER_INCR(sqlite3_pager_writedb_count);
+ }else{
+ PAGERTRACE(("NOSTORE %d page %d\n", PAGERID(pPager), pgno));
+ }
+ pager_set_pagehash(pList);
+ pList = pList->pDirty;
+ }
+
+ return rc;
+}
+
+/*
+** Ensure that the sub-journal file is open. If it is already open, this
+** function is a no-op.
+**
+** SQLITE_OK is returned if everything goes according to plan. An
+** SQLITE_IOERR_XXX error code is returned if a call to sqlite3OsOpen()
+** fails.
+*/
+static int openSubJournal(Pager *pPager){
+ int rc = SQLITE_OK;
+ if( !isOpen(pPager->sjfd) ){
+ if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY || pPager->subjInMemory ){
+ sqlite3MemJournalOpen(pPager->sjfd);
+ }else{
+ rc = pagerOpentemp(pPager, pPager->sjfd, SQLITE_OPEN_SUBJOURNAL);
+ }
+ }
+ return rc;
+}
+
+/*
+** Append a record of the current state of page pPg to the sub-journal.
+** It is the callers responsibility to use subjRequiresPage() to check
+** that it is really required before calling this function.
+**
+** If successful, set the bit corresponding to pPg->pgno in the bitvecs
+** for all open savepoints before returning.
+**
+** This function returns SQLITE_OK if everything is successful, an IO
+** error code if the attempt to write to the sub-journal fails, or
+** SQLITE_NOMEM if a malloc fails while setting a bit in a savepoint
+** bitvec.
+*/
+static int subjournalPage(PgHdr *pPg){
+ int rc = SQLITE_OK;
+ Pager *pPager = pPg->pPager;
+ if( pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+
+ /* Open the sub-journal, if it has not already been opened */
+ assert( pPager->useJournal );
+ assert( isOpen(pPager->jfd) || pagerUseWal(pPager) );
+ assert( isOpen(pPager->sjfd) || pPager->nSubRec==0 );
+ assert( pagerUseWal(pPager)
+ || pageInJournal(pPager, pPg)
+ || pPg->pgno>pPager->dbOrigSize
+ );
+ rc = openSubJournal(pPager);
+
+ /* If the sub-journal was opened successfully (or was already open),
+ ** write the journal record into the file. */
+ if( rc==SQLITE_OK ){
+ void *pData = pPg->pData;
+ i64 offset = (i64)pPager->nSubRec*(4+pPager->pageSize);
+ char *pData2;
+
+ CODEC2(pPager, pData, pPg->pgno, 7, return SQLITE_NOMEM, pData2);
+ PAGERTRACE(("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno));
+ rc = write32bits(pPager->sjfd, offset, pPg->pgno);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsWrite(pPager->sjfd, pData2, pPager->pageSize, offset+4);
+ }
+ }
+ }
+ if( rc==SQLITE_OK ){
+ pPager->nSubRec++;
+ assert( pPager->nSavepoint>0 );
+ rc = addToSavepointBitvecs(pPager, pPg->pgno);
+ }
+ return rc;
+}
+
+/*
+** This function is called by the pcache layer when it has reached some
+** soft memory limit. The first argument is a pointer to a Pager object
+** (cast as a void*). The pager is always 'purgeable' (not an in-memory
+** database). The second argument is a reference to a page that is
+** currently dirty but has no outstanding references. The page
+** is always associated with the Pager object passed as the first
+** argument.
+**
+** The job of this function is to make pPg clean by writing its contents
+** out to the database file, if possible. This may involve syncing the
+** journal file.
+**
+** If successful, sqlite3PcacheMakeClean() is called on the page and
+** SQLITE_OK returned. If an IO error occurs while trying to make the
+** page clean, the IO error code is returned. If the page cannot be
+** made clean for some other reason, but no error occurs, then SQLITE_OK
+** is returned by sqlite3PcacheMakeClean() is not called.
+*/
+static int pagerStress(void *p, PgHdr *pPg){
+ Pager *pPager = (Pager *)p;
+ int rc = SQLITE_OK;
+
+ assert( pPg->pPager==pPager );
+ assert( pPg->flags&PGHDR_DIRTY );
+
+ /* The doNotSpill NOSYNC bit is set during times when doing a sync of
+ ** journal (and adding a new header) is not allowed. This occurs
+ ** during calls to sqlite3PagerWrite() while trying to journal multiple
+ ** pages belonging to the same sector.
+ **
+ ** The doNotSpill ROLLBACK and OFF bits inhibits all cache spilling
+ ** regardless of whether or not a sync is required. This is set during
+ ** a rollback or by user request, respectively.
+ **
+ ** Spilling is also prohibited when in an error state since that could
+ ** lead to database corruption. In the current implementaton it
+ ** is impossible for sqlite3PcacheFetch() to be called with createFlag==1
+ ** while in the error state, hence it is impossible for this routine to
+ ** be called in the error state. Nevertheless, we include a NEVER()
+ ** test for the error state as a safeguard against future changes.
+ */
+ if( NEVER(pPager->errCode) ) return SQLITE_OK;
+ testcase( pPager->doNotSpill & SPILLFLAG_ROLLBACK );
+ testcase( pPager->doNotSpill & SPILLFLAG_OFF );
+ testcase( pPager->doNotSpill & SPILLFLAG_NOSYNC );
+ if( pPager->doNotSpill
+ && ((pPager->doNotSpill & (SPILLFLAG_ROLLBACK|SPILLFLAG_OFF))!=0
+ || (pPg->flags & PGHDR_NEED_SYNC)!=0)
+ ){
+ return SQLITE_OK;
+ }
+
+ pPg->pDirty = 0;
+ if( pagerUseWal(pPager) ){
+ /* Write a single frame for this page to the log. */
+ if( subjRequiresPage(pPg) ){
+ rc = subjournalPage(pPg);
+ }
+ if( rc==SQLITE_OK ){
+ rc = pagerWalFrames(pPager, pPg, 0, 0);
+ }
+ }else{
+
+ /* Sync the journal file if required. */
+ if( pPg->flags&PGHDR_NEED_SYNC
+ || pPager->eState==PAGER_WRITER_CACHEMOD
+ ){
+ rc = syncJournal(pPager, 1);
+ }
+
+ /* If the page number of this page is larger than the current size of
+ ** the database image, it may need to be written to the sub-journal.
+ ** This is because the call to pager_write_pagelist() below will not
+ ** actually write data to the file in this case.
+ **
+ ** Consider the following sequence of events:
+ **
+ ** BEGIN;
+ **
+ **
+ ** SAVEPOINT sp;
+ **
+ ** pagerStress(page X)
+ ** ROLLBACK TO sp;
+ **
+ ** If (X>Y), then when pagerStress is called page X will not be written
+ ** out to the database file, but will be dropped from the cache. Then,
+ ** following the "ROLLBACK TO sp" statement, reading page X will read
+ ** data from the database file. This will be the copy of page X as it
+ ** was when the transaction started, not as it was when "SAVEPOINT sp"
+ ** was executed.
+ **
+ ** The solution is to write the current data for page X into the
+ ** sub-journal file now (if it is not already there), so that it will
+ ** be restored to its current value when the "ROLLBACK TO sp" is
+ ** executed.
+ */
+ if( NEVER(
+ rc==SQLITE_OK && pPg->pgno>pPager->dbSize && subjRequiresPage(pPg)
+ ) ){
+ rc = subjournalPage(pPg);
+ }
+
+ /* Write the contents of the page out to the database file. */
+ if( rc==SQLITE_OK ){
+ assert( (pPg->flags&PGHDR_NEED_SYNC)==0 );
+ rc = pager_write_pagelist(pPager, pPg);
+ }
+ }
+
+ /* Mark the page as clean. */
+ if( rc==SQLITE_OK ){
+ PAGERTRACE(("STRESS %d page %d\n", PAGERID(pPager), pPg->pgno));
+ sqlite3PcacheMakeClean(pPg);
+ }
+
+ return pager_error(pPager, rc);
+}
+
+
+/*
+** Allocate and initialize a new Pager object and put a pointer to it
+** in *ppPager. The pager should eventually be freed by passing it
+** to sqlite3PagerClose().
+**
+** The zFilename argument is the path to the database file to open.
+** If zFilename is NULL then a randomly-named temporary file is created
+** and used as the file to be cached. Temporary files are be deleted
+** automatically when they are closed. If zFilename is ":memory:" then
+** all information is held in cache. It is never written to disk.
+** This can be used to implement an in-memory database.
+**
+** The nExtra parameter specifies the number of bytes of space allocated
+** along with each page reference. This space is available to the user
+** via the sqlite3PagerGetExtra() API.
+**
+** The flags argument is used to specify properties that affect the
+** operation of the pager. It should be passed some bitwise combination
+** of the PAGER_* flags.
+**
+** The vfsFlags parameter is a bitmask to pass to the flags parameter
+** of the xOpen() method of the supplied VFS when opening files.
+**
+** If the pager object is allocated and the specified file opened
+** successfully, SQLITE_OK is returned and *ppPager set to point to
+** the new pager object. If an error occurs, *ppPager is set to NULL
+** and error code returned. This function may return SQLITE_NOMEM
+** (sqlite3Malloc() is used to allocate memory), SQLITE_CANTOPEN or
+** various SQLITE_IO_XXX errors.
+*/
+SQLITE_PRIVATE int sqlite3PagerOpen(
+ sqlite3_vfs *pVfs, /* The virtual file system to use */
+ Pager **ppPager, /* OUT: Return the Pager structure here */
+ const char *zFilename, /* Name of the database file to open */
+ int nExtra, /* Extra bytes append to each in-memory page */
+ int flags, /* flags controlling this file */
+ int vfsFlags, /* flags passed through to sqlite3_vfs.xOpen() */
+ void (*xReinit)(DbPage*) /* Function to reinitialize pages */
+){
+ u8 *pPtr;
+ Pager *pPager = 0; /* Pager object to allocate and return */
+ int rc = SQLITE_OK; /* Return code */
+ int tempFile = 0; /* True for temp files (incl. in-memory files) */
+ int memDb = 0; /* True if this is an in-memory file */
+ int readOnly = 0; /* True if this is a read-only file */
+ int journalFileSize; /* Bytes to allocate for each journal fd */
+ char *zPathname = 0; /* Full path to database file */
+ int nPathname = 0; /* Number of bytes in zPathname */
+ int useJournal = (flags & PAGER_OMIT_JOURNAL)==0; /* False to omit journal */
+ int pcacheSize = sqlite3PcacheSize(); /* Bytes to allocate for PCache */
+ u32 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE; /* Default page size */
+ const char *zUri = 0; /* URI args to copy */
+ int nUri = 0; /* Number of bytes of URI args at *zUri */
+
+ /* Figure out how much space is required for each journal file-handle
+ ** (there are two of them, the main journal and the sub-journal). This
+ ** is the maximum space required for an in-memory journal file handle
+ ** and a regular journal file-handle. Note that a "regular journal-handle"
+ ** may be a wrapper capable of caching the first portion of the journal
+ ** file in memory to implement the atomic-write optimization (see
+ ** source file journal.c).
+ */
+ if( sqlite3JournalSize(pVfs)>sqlite3MemJournalSize() ){
+ journalFileSize = ROUND8(sqlite3JournalSize(pVfs));
+ }else{
+ journalFileSize = ROUND8(sqlite3MemJournalSize());
+ }
+
+ /* Set the output variable to NULL in case an error occurs. */
+ *ppPager = 0;
+
+#ifndef SQLITE_OMIT_MEMORYDB
+ if( flags & PAGER_MEMORY ){
+ memDb = 1;
+ if( zFilename && zFilename[0] ){
+ zPathname = sqlite3DbStrDup(0, zFilename);
+ if( zPathname==0 ) return SQLITE_NOMEM;
+ nPathname = sqlite3Strlen30(zPathname);
+ zFilename = 0;
+ }
+ }
+#endif
+
+ /* Compute and store the full pathname in an allocated buffer pointed
+ ** to by zPathname, length nPathname. Or, if this is a temporary file,
+ ** leave both nPathname and zPathname set to 0.
+ */
+ if( zFilename && zFilename[0] ){
+ const char *z;
+ nPathname = pVfs->mxPathname+1;
+ zPathname = sqlite3DbMallocRaw(0, nPathname*2);
+ if( zPathname==0 ){
+ return SQLITE_NOMEM;
+ }
+ zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
+ rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
+ nPathname = sqlite3Strlen30(zPathname);
+ z = zUri = &zFilename[sqlite3Strlen30(zFilename)+1];
+ while( *z ){
+ z += sqlite3Strlen30(z)+1;
+ z += sqlite3Strlen30(z)+1;
+ }
+ nUri = (int)(&z[1] - zUri);
+ assert( nUri>=0 );
+ if( rc==SQLITE_OK && nPathname+8>pVfs->mxPathname ){
+ /* This branch is taken when the journal path required by
+ ** the database being opened will be more than pVfs->mxPathname
+ ** bytes in length. This means the database cannot be opened,
+ ** as it will not be possible to open the journal file or even
+ ** check for a hot-journal before reading.
+ */
+ rc = SQLITE_CANTOPEN_BKPT;
+ }
+ if( rc!=SQLITE_OK ){
+ sqlite3DbFree(0, zPathname);
+ return rc;
+ }
+ }
+
+ /* Allocate memory for the Pager structure, PCache object, the
+ ** three file descriptors, the database file name and the journal
+ ** file name. The layout in memory is as follows:
+ **
+ ** Pager object (sizeof(Pager) bytes)
+ ** PCache object (sqlite3PcacheSize() bytes)
+ ** Database file handle (pVfs->szOsFile bytes)
+ ** Sub-journal file handle (journalFileSize bytes)
+ ** Main journal file handle (journalFileSize bytes)
+ ** Database file name (nPathname+1 bytes)
+ ** Journal file name (nPathname+8+1 bytes)
+ */
+ pPtr = (u8 *)sqlite3MallocZero(
+ ROUND8(sizeof(*pPager)) + /* Pager structure */
+ ROUND8(pcacheSize) + /* PCache object */
+ ROUND8(pVfs->szOsFile) + /* The main db file */
+ journalFileSize * 2 + /* The two journal files */
+ nPathname + 1 + nUri + /* zFilename */
+ nPathname + 8 + 2 /* zJournal */
+#ifndef SQLITE_OMIT_WAL
+ + nPathname + 4 + 2 /* zWal */
+#endif
+ );
+ assert( EIGHT_BYTE_ALIGNMENT(SQLITE_INT_TO_PTR(journalFileSize)) );
+ if( !pPtr ){
+ sqlite3DbFree(0, zPathname);
+ return SQLITE_NOMEM;
+ }
+ pPager = (Pager*)(pPtr);
+ pPager->pPCache = (PCache*)(pPtr += ROUND8(sizeof(*pPager)));
+ pPager->fd = (sqlite3_file*)(pPtr += ROUND8(pcacheSize));
+ pPager->sjfd = (sqlite3_file*)(pPtr += ROUND8(pVfs->szOsFile));
+ pPager->jfd = (sqlite3_file*)(pPtr += journalFileSize);
+ pPager->zFilename = (char*)(pPtr += journalFileSize);
+ assert( EIGHT_BYTE_ALIGNMENT(pPager->jfd) );
+
+ /* Fill in the Pager.zFilename and Pager.zJournal buffers, if required. */
+ if( zPathname ){
+ assert( nPathname>0 );
+ pPager->zJournal = (char*)(pPtr += nPathname + 1 + nUri);
+ memcpy(pPager->zFilename, zPathname, nPathname);
+ if( nUri ) memcpy(&pPager->zFilename[nPathname+1], zUri, nUri);
+ memcpy(pPager->zJournal, zPathname, nPathname);
+ memcpy(&pPager->zJournal[nPathname], "-journal\000", 8+2);
+ sqlite3FileSuffix3(pPager->zFilename, pPager->zJournal);
+#ifndef SQLITE_OMIT_WAL
+ pPager->zWal = &pPager->zJournal[nPathname+8+1];
+ memcpy(pPager->zWal, zPathname, nPathname);
+ memcpy(&pPager->zWal[nPathname], "-wal\000", 4+1);
+ sqlite3FileSuffix3(pPager->zFilename, pPager->zWal);
+#endif
+ sqlite3DbFree(0, zPathname);
+ }
+ pPager->pVfs = pVfs;
+ pPager->vfsFlags = vfsFlags;
+
+ /* Open the pager file.
+ */
+ if( zFilename && zFilename[0] ){
+ int fout = 0; /* VFS flags returned by xOpen() */
+ rc = sqlite3OsOpen(pVfs, pPager->zFilename, pPager->fd, vfsFlags, &fout);
+ assert( !memDb );
+ readOnly = (fout&SQLITE_OPEN_READONLY);
+
+ /* If the file was successfully opened for read/write access,
+ ** choose a default page size in case we have to create the
+ ** database file. The default page size is the maximum of:
+ **
+ ** + SQLITE_DEFAULT_PAGE_SIZE,
+ ** + The value returned by sqlite3OsSectorSize()
+ ** + The largest page size that can be written atomically.
+ */
+ if( rc==SQLITE_OK ){
+ int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
+ if( !readOnly ){
+ setSectorSize(pPager);
+ assert(SQLITE_DEFAULT_PAGE_SIZE<=SQLITE_MAX_DEFAULT_PAGE_SIZE);
+ if( szPageDfltsectorSize ){
+ if( pPager->sectorSize>SQLITE_MAX_DEFAULT_PAGE_SIZE ){
+ szPageDflt = SQLITE_MAX_DEFAULT_PAGE_SIZE;
+ }else{
+ szPageDflt = (u32)pPager->sectorSize;
+ }
+ }
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+ {
+ int ii;
+ assert(SQLITE_IOCAP_ATOMIC512==(512>>8));
+ assert(SQLITE_IOCAP_ATOMIC64K==(65536>>8));
+ assert(SQLITE_MAX_DEFAULT_PAGE_SIZE<=65536);
+ for(ii=szPageDflt; ii<=SQLITE_MAX_DEFAULT_PAGE_SIZE; ii=ii*2){
+ if( iDc&(SQLITE_IOCAP_ATOMIC|(ii>>8)) ){
+ szPageDflt = ii;
+ }
+ }
+ }
+#endif
+ }
+ pPager->noLock = sqlite3_uri_boolean(zFilename, "nolock", 0);
+ if( (iDc & SQLITE_IOCAP_IMMUTABLE)!=0
+ || sqlite3_uri_boolean(zFilename, "immutable", 0) ){
+ vfsFlags |= SQLITE_OPEN_READONLY;
+ goto act_like_temp_file;
+ }
+ }
+ }else{
+ /* If a temporary file is requested, it is not opened immediately.
+ ** In this case we accept the default page size and delay actually
+ ** opening the file until the first call to OsWrite().
+ **
+ ** This branch is also run for an in-memory database. An in-memory
+ ** database is the same as a temp-file that is never written out to
+ ** disk and uses an in-memory rollback journal.
+ **
+ ** This branch also runs for files marked as immutable.
+ */
+act_like_temp_file:
+ tempFile = 1;
+ pPager->eState = PAGER_READER; /* Pretend we already have a lock */
+ pPager->eLock = EXCLUSIVE_LOCK; /* Pretend we are in EXCLUSIVE locking mode */
+ pPager->noLock = 1; /* Do no locking */
+ readOnly = (vfsFlags&SQLITE_OPEN_READONLY);
+ }
+
+ /* The following call to PagerSetPagesize() serves to set the value of
+ ** Pager.pageSize and to allocate the Pager.pTmpSpace buffer.
+ */
+ if( rc==SQLITE_OK ){
+ assert( pPager->memDb==0 );
+ rc = sqlite3PagerSetPagesize(pPager, &szPageDflt, -1);
+ testcase( rc!=SQLITE_OK );
+ }
+
+ /* If an error occurred in either of the blocks above, free the
+ ** Pager structure and close the file.
+ */
+ if( rc!=SQLITE_OK ){
+ assert( !pPager->pTmpSpace );
+ sqlite3OsClose(pPager->fd);
+ sqlite3_free(pPager);
+ return rc;
+ }
+
+ /* Initialize the PCache object. */
+ assert( nExtra<1000 );
+ nExtra = ROUND8(nExtra);
+ sqlite3PcacheOpen(szPageDflt, nExtra, !memDb,
+ !memDb?pagerStress:0, (void *)pPager, pPager->pPCache);
+
+ PAGERTRACE(("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename));
+ IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename))
+
+ pPager->useJournal = (u8)useJournal;
+ /* pPager->stmtOpen = 0; */
+ /* pPager->stmtInUse = 0; */
+ /* pPager->nRef = 0; */
+ /* pPager->stmtSize = 0; */
+ /* pPager->stmtJSize = 0; */
+ /* pPager->nPage = 0; */
+ pPager->mxPgno = SQLITE_MAX_PAGE_COUNT;
+ /* pPager->state = PAGER_UNLOCK; */
+ /* pPager->errMask = 0; */
+ pPager->tempFile = (u8)tempFile;
+ assert( tempFile==PAGER_LOCKINGMODE_NORMAL
+ || tempFile==PAGER_LOCKINGMODE_EXCLUSIVE );
+ assert( PAGER_LOCKINGMODE_EXCLUSIVE==1 );
+ pPager->exclusiveMode = (u8)tempFile;
+ pPager->changeCountDone = pPager->tempFile;
+ pPager->memDb = (u8)memDb;
+ pPager->readOnly = (u8)readOnly;
+ assert( useJournal || pPager->tempFile );
+ pPager->noSync = pPager->tempFile;
+ if( pPager->noSync ){
+ assert( pPager->fullSync==0 );
+ assert( pPager->syncFlags==0 );
+ assert( pPager->walSyncFlags==0 );
+ assert( pPager->ckptSyncFlags==0 );
+ }else{
+ pPager->fullSync = 1;
+ pPager->syncFlags = SQLITE_SYNC_NORMAL;
+ pPager->walSyncFlags = SQLITE_SYNC_NORMAL | WAL_SYNC_TRANSACTIONS;
+ pPager->ckptSyncFlags = SQLITE_SYNC_NORMAL;
+ }
+ /* pPager->pFirst = 0; */
+ /* pPager->pFirstSynced = 0; */
+ /* pPager->pLast = 0; */
+ pPager->nExtra = (u16)nExtra;
+ pPager->journalSizeLimit = SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT;
+ assert( isOpen(pPager->fd) || tempFile );
+ setSectorSize(pPager);
+ if( !useJournal ){
+ pPager->journalMode = PAGER_JOURNALMODE_OFF;
+ }else if( memDb ){
+ pPager->journalMode = PAGER_JOURNALMODE_MEMORY;
+ }
+ /* pPager->xBusyHandler = 0; */
+ /* pPager->pBusyHandlerArg = 0; */
+ pPager->xReiniter = xReinit;
+ /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
+ /* pPager->szMmap = SQLITE_DEFAULT_MMAP_SIZE // will be set by btree.c */
+
+ *ppPager = pPager;
+ return SQLITE_OK;
+}
+
+
+/* Verify that the database file has not be deleted or renamed out from
+** under the pager. Return SQLITE_OK if the database is still were it ought
+** to be on disk. Return non-zero (SQLITE_READONLY_DBMOVED or some other error
+** code from sqlite3OsAccess()) if the database has gone missing.
+*/
+static int databaseIsUnmoved(Pager *pPager){
+ int bHasMoved = 0;
+ int rc;
+
+ if( pPager->tempFile ) return SQLITE_OK;
+ if( pPager->dbSize==0 ) return SQLITE_OK;
+ assert( pPager->zFilename && pPager->zFilename[0] );
+ rc = sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_HAS_MOVED, &bHasMoved);
+ if( rc==SQLITE_NOTFOUND ){
+ /* If the HAS_MOVED file-control is unimplemented, assume that the file
+ ** has not been moved. That is the historical behavior of SQLite: prior to
+ ** version 3.8.3, it never checked */
+ rc = SQLITE_OK;
+ }else if( rc==SQLITE_OK && bHasMoved ){
+ rc = SQLITE_READONLY_DBMOVED;
+ }
+ return rc;
+}
+
+
+/*
+** This function is called after transitioning from PAGER_UNLOCK to
+** PAGER_SHARED state. It tests if there is a hot journal present in
+** the file-system for the given pager. A hot journal is one that
+** needs to be played back. According to this function, a hot-journal
+** file exists if the following criteria are met:
+**
+** * The journal file exists in the file system, and
+** * No process holds a RESERVED or greater lock on the database file, and
+** * The database file itself is greater than 0 bytes in size, and
+** * The first byte of the journal file exists and is not 0x00.
+**
+** If the current size of the database file is 0 but a journal file
+** exists, that is probably an old journal left over from a prior
+** database with the same name. In this case the journal file is
+** just deleted using OsDelete, *pExists is set to 0 and SQLITE_OK
+** is returned.
+**
+** This routine does not check if there is a master journal filename
+** at the end of the file. If there is, and that master journal file
+** does not exist, then the journal file is not really hot. In this
+** case this routine will return a false-positive. The pager_playback()
+** routine will discover that the journal file is not really hot and
+** will not roll it back.
+**
+** If a hot-journal file is found to exist, *pExists is set to 1 and
+** SQLITE_OK returned. If no hot-journal file is present, *pExists is
+** set to 0 and SQLITE_OK returned. If an IO error occurs while trying
+** to determine whether or not a hot-journal file exists, the IO error
+** code is returned and the value of *pExists is undefined.
+*/
+static int hasHotJournal(Pager *pPager, int *pExists){
+ sqlite3_vfs * const pVfs = pPager->pVfs;
+ int rc = SQLITE_OK; /* Return code */
+ int exists = 1; /* True if a journal file is present */
+ int jrnlOpen = !!isOpen(pPager->jfd);
+
+ assert( pPager->useJournal );
+ assert( isOpen(pPager->fd) );
+ assert( pPager->eState==PAGER_OPEN );
+
+ assert( jrnlOpen==0 || ( sqlite3OsDeviceCharacteristics(pPager->jfd) &
+ SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
+ ));
+
+ *pExists = 0;
+ if( !jrnlOpen ){
+ rc = sqlite3OsAccess(pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &exists);
+ }
+ if( rc==SQLITE_OK && exists ){
+ int locked = 0; /* True if some process holds a RESERVED lock */
+
+ /* Race condition here: Another process might have been holding the
+ ** the RESERVED lock and have a journal open at the sqlite3OsAccess()
+ ** call above, but then delete the journal and drop the lock before
+ ** we get to the following sqlite3OsCheckReservedLock() call. If that
+ ** is the case, this routine might think there is a hot journal when
+ ** in fact there is none. This results in a false-positive which will
+ ** be dealt with by the playback routine. Ticket #3883.
+ */
+ rc = sqlite3OsCheckReservedLock(pPager->fd, &locked);
+ if( rc==SQLITE_OK && !locked ){
+ Pgno nPage; /* Number of pages in database file */
+
+ rc = pagerPagecount(pPager, &nPage);
+ if( rc==SQLITE_OK ){
+ /* If the database is zero pages in size, that means that either (1) the
+ ** journal is a remnant from a prior database with the same name where
+ ** the database file but not the journal was deleted, or (2) the initial
+ ** transaction that populates a new database is being rolled back.
+ ** In either case, the journal file can be deleted. However, take care
+ ** not to delete the journal file if it is already open due to
+ ** journal_mode=PERSIST.
+ */
+ if( nPage==0 && !jrnlOpen ){
+ sqlite3BeginBenignMalloc();
+ if( pagerLockDb(pPager, RESERVED_LOCK)==SQLITE_OK ){
+ sqlite3OsDelete(pVfs, pPager->zJournal, 0);
+ if( !pPager->exclusiveMode ) pagerUnlockDb(pPager, SHARED_LOCK);
+ }
+ sqlite3EndBenignMalloc();
+ }else{
+ /* The journal file exists and no other connection has a reserved
+ ** or greater lock on the database file. Now check that there is
+ ** at least one non-zero bytes at the start of the journal file.
+ ** If there is, then we consider this journal to be hot. If not,
+ ** it can be ignored.
+ */
+ if( !jrnlOpen ){
+ int f = SQLITE_OPEN_READONLY|SQLITE_OPEN_MAIN_JOURNAL;
+ rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &f);
+ }
+ if( rc==SQLITE_OK ){
+ u8 first = 0;
+ rc = sqlite3OsRead(pPager->jfd, (void *)&first, 1, 0);
+ if( rc==SQLITE_IOERR_SHORT_READ ){
+ rc = SQLITE_OK;
+ }
+ if( !jrnlOpen ){
+ sqlite3OsClose(pPager->jfd);
+ }
+ *pExists = (first!=0);
+ }else if( rc==SQLITE_CANTOPEN ){
+ /* If we cannot open the rollback journal file in order to see if
+ ** its has a zero header, that might be due to an I/O error, or
+ ** it might be due to the race condition described above and in
+ ** ticket #3883. Either way, assume that the journal is hot.
+ ** This might be a false positive. But if it is, then the
+ ** automatic journal playback and recovery mechanism will deal
+ ** with it under an EXCLUSIVE lock where we do not need to
+ ** worry so much with race conditions.
+ */
+ *pExists = 1;
+ rc = SQLITE_OK;
+ }
+ }
+ }
+ }
+ }
+
+ return rc;
+}
+
+/*
+** This function is called to obtain a shared lock on the database file.
+** It is illegal to call sqlite3PagerAcquire() until after this function
+** has been successfully called. If a shared-lock is already held when
+** this function is called, it is a no-op.
+**
+** The following operations are also performed by this function.
+**
+** 1) If the pager is currently in PAGER_OPEN state (no lock held
+** on the database file), then an attempt is made to obtain a
+** SHARED lock on the database file. Immediately after obtaining
+** the SHARED lock, the file-system is checked for a hot-journal,
+** which is played back if present. Following any hot-journal
+** rollback, the contents of the cache are validated by checking
+** the 'change-counter' field of the database file header and
+** discarded if they are found to be invalid.
+**
+** 2) If the pager is running in exclusive-mode, and there are currently
+** no outstanding references to any pages, and is in the error state,
+** then an attempt is made to clear the error state by discarding
+** the contents of the page cache and rolling back any open journal
+** file.
+**
+** If everything is successful, SQLITE_OK is returned. If an IO error
+** occurs while locking the database, checking for a hot-journal file or
+** rolling back a journal file, the IO error code is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+
+ /* This routine is only called from b-tree and only when there are no
+ ** outstanding pages. This implies that the pager state should either
+ ** be OPEN or READER. READER is only possible if the pager is or was in
+ ** exclusive access mode.
+ */
+ assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
+ if( NEVER(MEMDB && pPager->errCode) ){ return pPager->errCode; }
+
+ if( !pagerUseWal(pPager) && pPager->eState==PAGER_OPEN ){
+ int bHotJournal = 1; /* True if there exists a hot journal-file */
+
+ assert( !MEMDB );
+
+ rc = pager_wait_on_lock(pPager, SHARED_LOCK);
+ if( rc!=SQLITE_OK ){
+ assert( pPager->eLock==NO_LOCK || pPager->eLock==UNKNOWN_LOCK );
+ goto failed;
+ }
+
+ /* If a journal file exists, and there is no RESERVED lock on the
+ ** database file, then it either needs to be played back or deleted.
+ */
+ if( pPager->eLock<=SHARED_LOCK ){
+ rc = hasHotJournal(pPager, &bHotJournal);
+ }
+ if( rc!=SQLITE_OK ){
+ goto failed;
+ }
+ if( bHotJournal ){
+ if( pPager->readOnly ){
+ rc = SQLITE_READONLY_ROLLBACK;
+ goto failed;
+ }
+
+ /* Get an EXCLUSIVE lock on the database file. At this point it is
+ ** important that a RESERVED lock is not obtained on the way to the
+ ** EXCLUSIVE lock. If it were, another process might open the
+ ** database file, detect the RESERVED lock, and conclude that the
+ ** database is safe to read while this process is still rolling the
+ ** hot-journal back.
+ **
+ ** Because the intermediate RESERVED lock is not requested, any
+ ** other process attempting to access the database file will get to
+ ** this point in the code and fail to obtain its own EXCLUSIVE lock
+ ** on the database file.
+ **
+ ** Unless the pager is in locking_mode=exclusive mode, the lock is
+ ** downgraded to SHARED_LOCK before this function returns.
+ */
+ rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
+ if( rc!=SQLITE_OK ){
+ goto failed;
+ }
+
+ /* If it is not already open and the file exists on disk, open the
+ ** journal for read/write access. Write access is required because
+ ** in exclusive-access mode the file descriptor will be kept open
+ ** and possibly used for a transaction later on. Also, write-access
+ ** is usually required to finalize the journal in journal_mode=persist
+ ** mode (and also for journal_mode=truncate on some systems).
+ **
+ ** If the journal does not exist, it usually means that some
+ ** other connection managed to get in and roll it back before
+ ** this connection obtained the exclusive lock above. Or, it
+ ** may mean that the pager was in the error-state when this
+ ** function was called and the journal file does not exist.
+ */
+ if( !isOpen(pPager->jfd) ){
+ sqlite3_vfs * const pVfs = pPager->pVfs;
+ int bExists; /* True if journal file exists */
+ rc = sqlite3OsAccess(
+ pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &bExists);
+ if( rc==SQLITE_OK && bExists ){
+ int fout = 0;
+ int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
+ assert( !pPager->tempFile );
+ rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
+ assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+ if( rc==SQLITE_OK && fout&SQLITE_OPEN_READONLY ){
+ rc = SQLITE_CANTOPEN_BKPT;
+ sqlite3OsClose(pPager->jfd);
+ }
+ }
+ }
+
+ /* Playback and delete the journal. Drop the database write
+ ** lock and reacquire the read lock. Purge the cache before
+ ** playing back the hot-journal so that we don't end up with
+ ** an inconsistent cache. Sync the hot journal before playing
+ ** it back since the process that crashed and left the hot journal
+ ** probably did not sync it and we are required to always sync
+ ** the journal before playing it back.
+ */
+ if( isOpen(pPager->jfd) ){
+ assert( rc==SQLITE_OK );
+ rc = pagerSyncHotJournal(pPager);
+ if( rc==SQLITE_OK ){
+ rc = pager_playback(pPager, 1);
+ pPager->eState = PAGER_OPEN;
+ }
+ }else if( !pPager->exclusiveMode ){
+ pagerUnlockDb(pPager, SHARED_LOCK);
+ }
+
+ if( rc!=SQLITE_OK ){
+ /* This branch is taken if an error occurs while trying to open
+ ** or roll back a hot-journal while holding an EXCLUSIVE lock. The
+ ** pager_unlock() routine will be called before returning to unlock
+ ** the file. If the unlock attempt fails, then Pager.eLock must be
+ ** set to UNKNOWN_LOCK (see the comment above the #define for
+ ** UNKNOWN_LOCK above for an explanation).
+ **
+ ** In order to get pager_unlock() to do this, set Pager.eState to
+ ** PAGER_ERROR now. This is not actually counted as a transition
+ ** to ERROR state in the state diagram at the top of this file,
+ ** since we know that the same call to pager_unlock() will very
+ ** shortly transition the pager object to the OPEN state. Calling
+ ** assert_pager_state() would fail now, as it should not be possible
+ ** to be in ERROR state when there are zero outstanding page
+ ** references.
+ */
+ pager_error(pPager, rc);
+ goto failed;
+ }
+
+ assert( pPager->eState==PAGER_OPEN );
+ assert( (pPager->eLock==SHARED_LOCK)
+ || (pPager->exclusiveMode && pPager->eLock>SHARED_LOCK)
+ );
+ }
+
+ if( !pPager->tempFile && (
+ pPager->pBackup
+ || sqlite3PcachePagecount(pPager->pPCache)>0
+ || USEFETCH(pPager)
+ )){
+ /* The shared-lock has just been acquired on the database file
+ ** and there are already pages in the cache (from a previous
+ ** read or write transaction). Check to see if the database
+ ** has been modified. If the database has changed, flush the
+ ** cache.
+ **
+ ** Database changes is detected by looking at 15 bytes beginning
+ ** at offset 24 into the file. The first 4 of these 16 bytes are
+ ** a 32-bit counter that is incremented with each change. The
+ ** other bytes change randomly with each file change when
+ ** a codec is in use.
+ **
+ ** There is a vanishingly small chance that a change will not be
+ ** detected. The chance of an undetected change is so small that
+ ** it can be neglected.
+ */
+ Pgno nPage = 0;
+ char dbFileVers[sizeof(pPager->dbFileVers)];
+
+ rc = pagerPagecount(pPager, &nPage);
+ if( rc ) goto failed;
+
+ if( nPage>0 ){
+ IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
+ rc = sqlite3OsRead(pPager->fd, &dbFileVers, sizeof(dbFileVers), 24);
+ if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
+ goto failed;
+ }
+ }else{
+ memset(dbFileVers, 0, sizeof(dbFileVers));
+ }
+
+ if( memcmp(pPager->dbFileVers, dbFileVers, sizeof(dbFileVers))!=0 ){
+ pager_reset(pPager);
+
+ /* Unmap the database file. It is possible that external processes
+ ** may have truncated the database file and then extended it back
+ ** to its original size while this process was not holding a lock.
+ ** In this case there may exist a Pager.pMap mapping that appears
+ ** to be the right size but is not actually valid. Avoid this
+ ** possibility by unmapping the db here. */
+ if( USEFETCH(pPager) ){
+ sqlite3OsUnfetch(pPager->fd, 0, 0);
+ }
+ }
+ }
+
+ /* If there is a WAL file in the file-system, open this database in WAL
+ ** mode. Otherwise, the following function call is a no-op.
+ */
+ rc = pagerOpenWalIfPresent(pPager);
+#ifndef SQLITE_OMIT_WAL
+ assert( pPager->pWal==0 || rc==SQLITE_OK );
+#endif
+ }
+
+ if( pagerUseWal(pPager) ){
+ assert( rc==SQLITE_OK );
+ rc = pagerBeginReadTransaction(pPager);
+ }
+
+ if( pPager->eState==PAGER_OPEN && rc==SQLITE_OK ){
+ rc = pagerPagecount(pPager, &pPager->dbSize);
+ }
+
+ failed:
+ if( rc!=SQLITE_OK ){
+ assert( !MEMDB );
+ pager_unlock(pPager);
+ assert( pPager->eState==PAGER_OPEN );
+ }else{
+ pPager->eState = PAGER_READER;
+ }
+ return rc;
+}
+
+/*
+** If the reference count has reached zero, rollback any active
+** transaction and unlock the pager.
+**
+** Except, in locking_mode=EXCLUSIVE when there is nothing to in
+** the rollback journal, the unlock is not performed and there is
+** nothing to rollback, so this routine is a no-op.
+*/
+static void pagerUnlockIfUnused(Pager *pPager){
+ if( pPager->nMmapOut==0 && (sqlite3PcacheRefCount(pPager->pPCache)==0) ){
+ pagerUnlockAndRollback(pPager);
+ }
+}
+
+/*
+** Acquire a reference to page number pgno in pager pPager (a page
+** reference has type DbPage*). If the requested reference is
+** successfully obtained, it is copied to *ppPage and SQLITE_OK returned.
+**
+** If the requested page is already in the cache, it is returned.
+** Otherwise, a new page object is allocated and populated with data
+** read from the database file. In some cases, the pcache module may
+** choose not to allocate a new page object and may reuse an existing
+** object with no outstanding references.
+**
+** The extra data appended to a page is always initialized to zeros the
+** first time a page is loaded into memory. If the page requested is
+** already in the cache when this function is called, then the extra
+** data is left as it was when the page object was last used.
+**
+** If the database image is smaller than the requested page or if a
+** non-zero value is passed as the noContent parameter and the
+** requested page is not already stored in the cache, then no
+** actual disk read occurs. In this case the memory image of the
+** page is initialized to all zeros.
+**
+** If noContent is true, it means that we do not care about the contents
+** of the page. This occurs in two scenarios:
+**
+** a) When reading a free-list leaf page from the database, and
+**
+** b) When a savepoint is being rolled back and we need to load
+** a new page into the cache to be filled with the data read
+** from the savepoint journal.
+**
+** If noContent is true, then the data returned is zeroed instead of
+** being read from the database. Additionally, the bits corresponding
+** to pgno in Pager.pInJournal (bitvec of pages already written to the
+** journal file) and the PagerSavepoint.pInSavepoint bitvecs of any open
+** savepoints are set. This means if the page is made writable at any
+** point in the future, using a call to sqlite3PagerWrite(), its contents
+** will not be journaled. This saves IO.
+**
+** The acquisition might fail for several reasons. In all cases,
+** an appropriate error code is returned and *ppPage is set to NULL.
+**
+** See also sqlite3PagerLookup(). Both this routine and Lookup() attempt
+** to find a page in the in-memory cache first. If the page is not already
+** in memory, this routine goes to disk to read it in whereas Lookup()
+** just returns 0. This routine acquires a read-lock the first time it
+** has to go to disk, and could also playback an old journal if necessary.
+** Since Lookup() never goes to disk, it never has to deal with locks
+** or journal files.
+*/
+SQLITE_PRIVATE int sqlite3PagerAcquire(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ int rc = SQLITE_OK;
+ PgHdr *pPg = 0;
+ u32 iFrame = 0; /* Frame to read from WAL file */
+ const int noContent = (flags & PAGER_GET_NOCONTENT);
+
+ /* It is acceptable to use a read-only (mmap) page for any page except
+ ** page 1 if there is no write-transaction open or the ACQUIRE_READONLY
+ ** flag was specified by the caller. And so long as the db is not a
+ ** temporary or in-memory database. */
+ const int bMmapOk = (pgno!=1 && USEFETCH(pPager)
+ && (pPager->eState==PAGER_READER || (flags & PAGER_GET_READONLY))
+#ifdef SQLITE_HAS_CODEC
+ && pPager->xCodec==0
+#endif
+ );
+
+ assert( pPager->eState>=PAGER_READER );
+ assert( assert_pager_state(pPager) );
+ assert( noContent==0 || bMmapOk==0 );
+
+ if( pgno==0 ){
+ return SQLITE_CORRUPT_BKPT;
+ }
+
+ /* If the pager is in the error state, return an error immediately.
+ ** Otherwise, request the page from the PCache layer. */
+ if( pPager->errCode!=SQLITE_OK ){
+ rc = pPager->errCode;
+ }else{
+
+ if( bMmapOk && pagerUseWal(pPager) ){
+ rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
+ if( rc!=SQLITE_OK ) goto pager_acquire_err;
+ }
+
+ if( bMmapOk && iFrame==0 ){
+ void *pData = 0;
+
+ rc = sqlite3OsFetch(pPager->fd,
+ (i64)(pgno-1) * pPager->pageSize, pPager->pageSize, &pData
+ );
+
+ if( rc==SQLITE_OK && pData ){
+ if( pPager->eState>PAGER_READER ){
+ (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
+ }
+ if( pPg==0 ){
+ rc = pagerAcquireMapPage(pPager, pgno, pData, &pPg);
+ }else{
+ sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1)*pPager->pageSize, pData);
+ }
+ if( pPg ){
+ assert( rc==SQLITE_OK );
+ *ppPage = pPg;
+ return SQLITE_OK;
+ }
+ }
+ if( rc!=SQLITE_OK ){
+ goto pager_acquire_err;
+ }
+ }
+
+ rc = sqlite3PcacheFetch(pPager->pPCache, pgno, 1, ppPage);
+ }
+
+ if( rc!=SQLITE_OK ){
+ /* Either the call to sqlite3PcacheFetch() returned an error or the
+ ** pager was already in the error-state when this function was called.
+ ** Set pPg to 0 and jump to the exception handler. */
+ pPg = 0;
+ goto pager_acquire_err;
+ }
+ assert( (*ppPage)->pgno==pgno );
+ assert( (*ppPage)->pPager==pPager || (*ppPage)->pPager==0 );
+
+ if( (*ppPage)->pPager && !noContent ){
+ /* In this case the pcache already contains an initialized copy of
+ ** the page. Return without further ado. */
+ assert( pgno<=PAGER_MAX_PGNO && pgno!=PAGER_MJ_PGNO(pPager) );
+ pPager->aStat[PAGER_STAT_HIT]++;
+ return SQLITE_OK;
+
+ }else{
+ /* The pager cache has created a new page. Its content needs to
+ ** be initialized. */
+
+ pPg = *ppPage;
+ pPg->pPager = pPager;
+
+ /* The maximum page number is 2^31. Return SQLITE_CORRUPT if a page
+ ** number greater than this, or the unused locking-page, is requested. */
+ if( pgno>PAGER_MAX_PGNO || pgno==PAGER_MJ_PGNO(pPager) ){
+ rc = SQLITE_CORRUPT_BKPT;
+ goto pager_acquire_err;
+ }
+
+ if( MEMDB || pPager->dbSizefd) ){
+ if( pgno>pPager->mxPgno ){
+ rc = SQLITE_FULL;
+ goto pager_acquire_err;
+ }
+ if( noContent ){
+ /* Failure to set the bits in the InJournal bit-vectors is benign.
+ ** It merely means that we might do some extra work to journal a
+ ** page that does not need to be journaled. Nevertheless, be sure
+ ** to test the case where a malloc error occurs while trying to set
+ ** a bit in a bit vector.
+ */
+ sqlite3BeginBenignMalloc();
+ if( pgno<=pPager->dbOrigSize ){
+ TESTONLY( rc = ) sqlite3BitvecSet(pPager->pInJournal, pgno);
+ testcase( rc==SQLITE_NOMEM );
+ }
+ TESTONLY( rc = ) addToSavepointBitvecs(pPager, pgno);
+ testcase( rc==SQLITE_NOMEM );
+ sqlite3EndBenignMalloc();
+ }
+ memset(pPg->pData, 0, pPager->pageSize);
+ IOTRACE(("ZERO %p %d\n", pPager, pgno));
+ }else{
+ if( pagerUseWal(pPager) && bMmapOk==0 ){
+ rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
+ if( rc!=SQLITE_OK ) goto pager_acquire_err;
+ }
+ assert( pPg->pPager==pPager );
+ pPager->aStat[PAGER_STAT_MISS]++;
+ rc = readDbPage(pPg, iFrame);
+ if( rc!=SQLITE_OK ){
+ goto pager_acquire_err;
+ }
+ }
+ pager_set_pagehash(pPg);
+ }
+
+ return SQLITE_OK;
+
+pager_acquire_err:
+ assert( rc!=SQLITE_OK );
+ if( pPg ){
+ sqlite3PcacheDrop(pPg);
+ }
+ pagerUnlockIfUnused(pPager);
+
+ *ppPage = 0;
+ return rc;
+}
+
+/*
+** Acquire a page if it is already in the in-memory cache. Do
+** not read the page from disk. Return a pointer to the page,
+** or 0 if the page is not in cache.
+**
+** See also sqlite3PagerGet(). The difference between this routine
+** and sqlite3PagerGet() is that _get() will go to the disk and read
+** in the page if the page is not already in cache. This routine
+** returns NULL if the page is not in cache or if a disk I/O error
+** has ever happened.
+*/
+SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){
+ PgHdr *pPg = 0;
+ assert( pPager!=0 );
+ assert( pgno!=0 );
+ assert( pPager->pPCache!=0 );
+ assert( pPager->eState>=PAGER_READER && pPager->eState!=PAGER_ERROR );
+ sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
+ return pPg;
+}
+
+/*
+** Release a page reference.
+**
+** If the number of references to the page drop to zero, then the
+** page is added to the LRU list. When all references to all pages
+** are released, a rollback occurs and the lock on the database is
+** removed.
+*/
+SQLITE_PRIVATE void sqlite3PagerUnrefNotNull(DbPage *pPg){
+ Pager *pPager;
+ assert( pPg!=0 );
+ pPager = pPg->pPager;
+ if( pPg->flags & PGHDR_MMAP ){
+ pagerReleaseMapPage(pPg);
+ }else{
+ sqlite3PcacheRelease(pPg);
+ }
+ pagerUnlockIfUnused(pPager);
+}
+SQLITE_PRIVATE void sqlite3PagerUnref(DbPage *pPg){
+ if( pPg ) sqlite3PagerUnrefNotNull(pPg);
+}
+
+/*
+** This function is called at the start of every write transaction.
+** There must already be a RESERVED or EXCLUSIVE lock on the database
+** file when this routine is called.
+**
+** Open the journal file for pager pPager and write a journal header
+** to the start of it. If there are active savepoints, open the sub-journal
+** as well. This function is only used when the journal file is being
+** opened to write a rollback log for a transaction. It is not used
+** when opening a hot journal file to roll it back.
+**
+** If the journal file is already open (as it may be in exclusive mode),
+** then this function just writes a journal header to the start of the
+** already open file.
+**
+** Whether or not the journal file is opened by this function, the
+** Pager.pInJournal bitvec structure is allocated.
+**
+** Return SQLITE_OK if everything is successful. Otherwise, return
+** SQLITE_NOMEM if the attempt to allocate Pager.pInJournal fails, or
+** an IO error code if opening or writing the journal file fails.
+*/
+static int pager_open_journal(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+ sqlite3_vfs * const pVfs = pPager->pVfs; /* Local cache of vfs pointer */
+
+ assert( pPager->eState==PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->pInJournal==0 );
+
+ /* If already in the error state, this function is a no-op. But on
+ ** the other hand, this routine is never called if we are already in
+ ** an error state. */
+ if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+ if( !pagerUseWal(pPager) && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+ pPager->pInJournal = sqlite3BitvecCreate(pPager->dbSize);
+ if( pPager->pInJournal==0 ){
+ return SQLITE_NOMEM;
+ }
+
+ /* Open the journal file if it is not already open. */
+ if( !isOpen(pPager->jfd) ){
+ if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ){
+ sqlite3MemJournalOpen(pPager->jfd);
+ }else{
+ const int flags = /* VFS flags to open journal file */
+ SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
+ (pPager->tempFile ?
+ (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL):
+ (SQLITE_OPEN_MAIN_JOURNAL)
+ );
+
+ /* Verify that the database still has the same name as it did when
+ ** it was originally opened. */
+ rc = databaseIsUnmoved(pPager);
+ if( rc==SQLITE_OK ){
+#ifdef SQLITE_ENABLE_ATOMIC_WRITE
+ rc = sqlite3JournalOpen(
+ pVfs, pPager->zJournal, pPager->jfd, flags, jrnlBufferSize(pPager)
+ );
+#else
+ rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
+#endif
+ }
+ }
+ assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+ }
+
+
+ /* Write the first journal header to the journal file and open
+ ** the sub-journal if necessary.
+ */
+ if( rc==SQLITE_OK ){
+ /* TODO: Check if all of these are really required. */
+ pPager->nRec = 0;
+ pPager->journalOff = 0;
+ pPager->setMaster = 0;
+ pPager->journalHdr = 0;
+ rc = writeJournalHdr(pPager);
+ }
+ }
+
+ if( rc!=SQLITE_OK ){
+ sqlite3BitvecDestroy(pPager->pInJournal);
+ pPager->pInJournal = 0;
+ }else{
+ assert( pPager->eState==PAGER_WRITER_LOCKED );
+ pPager->eState = PAGER_WRITER_CACHEMOD;
+ }
+
+ return rc;
+}
+
+/*
+** Begin a write-transaction on the specified pager object. If a
+** write-transaction has already been opened, this function is a no-op.
+**
+** If the exFlag argument is false, then acquire at least a RESERVED
+** lock on the database file. If exFlag is true, then acquire at least
+** an EXCLUSIVE lock. If such a lock is already held, no locking
+** functions need be called.
+**
+** If the subjInMemory argument is non-zero, then any sub-journal opened
+** within this transaction will be opened as an in-memory file. This
+** has no effect if the sub-journal is already opened (as it may be when
+** running in exclusive mode) or if the transaction does not require a
+** sub-journal. If the subjInMemory argument is zero, then any required
+** sub-journal is implemented in-memory if pPager is an in-memory database,
+** or using a temporary file otherwise.
+*/
+SQLITE_PRIVATE int sqlite3PagerBegin(Pager *pPager, int exFlag, int subjInMemory){
+ int rc = SQLITE_OK;
+
+ if( pPager->errCode ) return pPager->errCode;
+ assert( pPager->eState>=PAGER_READER && pPager->eStatesubjInMemory = (u8)subjInMemory;
+
+ if( ALWAYS(pPager->eState==PAGER_READER) ){
+ assert( pPager->pInJournal==0 );
+
+ if( pagerUseWal(pPager) ){
+ /* If the pager is configured to use locking_mode=exclusive, and an
+ ** exclusive lock on the database is not already held, obtain it now.
+ */
+ if( pPager->exclusiveMode && sqlite3WalExclusiveMode(pPager->pWal, -1) ){
+ rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ sqlite3WalExclusiveMode(pPager->pWal, 1);
+ }
+
+ /* Grab the write lock on the log file. If successful, upgrade to
+ ** PAGER_RESERVED state. Otherwise, return an error code to the caller.
+ ** The busy-handler is not invoked if another connection already
+ ** holds the write-lock. If possible, the upper layer will call it.
+ */
+ rc = sqlite3WalBeginWriteTransaction(pPager->pWal);
+ }else{
+ /* Obtain a RESERVED lock on the database file. If the exFlag parameter
+ ** is true, then immediately upgrade this to an EXCLUSIVE lock. The
+ ** busy-handler callback can be used when upgrading to the EXCLUSIVE
+ ** lock, but not when obtaining the RESERVED lock.
+ */
+ rc = pagerLockDb(pPager, RESERVED_LOCK);
+ if( rc==SQLITE_OK && exFlag ){
+ rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+ }
+ }
+
+ if( rc==SQLITE_OK ){
+ /* Change to WRITER_LOCKED state.
+ **
+ ** WAL mode sets Pager.eState to PAGER_WRITER_LOCKED or CACHEMOD
+ ** when it has an open transaction, but never to DBMOD or FINISHED.
+ ** This is because in those states the code to roll back savepoint
+ ** transactions may copy data from the sub-journal into the database
+ ** file as well as into the page cache. Which would be incorrect in
+ ** WAL mode.
+ */
+ pPager->eState = PAGER_WRITER_LOCKED;
+ pPager->dbHintSize = pPager->dbSize;
+ pPager->dbFileSize = pPager->dbSize;
+ pPager->dbOrigSize = pPager->dbSize;
+ pPager->journalOff = 0;
+ }
+
+ assert( rc==SQLITE_OK || pPager->eState==PAGER_READER );
+ assert( rc!=SQLITE_OK || pPager->eState==PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+ }
+
+ PAGERTRACE(("TRANSACTION %d\n", PAGERID(pPager)));
+ return rc;
+}
+
+/*
+** Mark a single data page as writeable. The page is written into the
+** main journal or sub-journal as required. If the page is written into
+** one of the journals, the corresponding bit is set in the
+** Pager.pInJournal bitvec and the PagerSavepoint.pInSavepoint bitvecs
+** of any open savepoints as appropriate.
+*/
+static int pager_write(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ int rc = SQLITE_OK;
+ int inJournal;
+
+ /* This routine is not called unless a write-transaction has already
+ ** been started. The journal file may or may not be open at this point.
+ ** It is never called in the ERROR state.
+ */
+ assert( pPager->eState==PAGER_WRITER_LOCKED
+ || pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->errCode==0 );
+ assert( pPager->readOnly==0 );
+
+ CHECK_PAGE(pPg);
+
+ /* The journal file needs to be opened. Higher level routines have already
+ ** obtained the necessary locks to begin the write-transaction, but the
+ ** rollback journal might not yet be open. Open it now if this is the case.
+ **
+ ** This is done before calling sqlite3PcacheMakeDirty() on the page.
+ ** Otherwise, if it were done after calling sqlite3PcacheMakeDirty(), then
+ ** an error might occur and the pager would end up in WRITER_LOCKED state
+ ** with pages marked as dirty in the cache.
+ */
+ if( pPager->eState==PAGER_WRITER_LOCKED ){
+ rc = pager_open_journal(pPager);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+ assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
+ assert( assert_pager_state(pPager) );
+
+ /* Mark the page as dirty. If the page has already been written
+ ** to the journal then we can return right away.
+ */
+ sqlite3PcacheMakeDirty(pPg);
+ inJournal = pageInJournal(pPager, pPg);
+ if( inJournal && (pPager->nSavepoint==0 || !subjRequiresPage(pPg)) ){
+ assert( !pagerUseWal(pPager) );
+ }else{
+
+ /* The transaction journal now exists and we have a RESERVED or an
+ ** EXCLUSIVE lock on the main database file. Write the current page to
+ ** the transaction journal if it is not there already.
+ */
+ if( !inJournal && !pagerUseWal(pPager) ){
+ assert( pagerUseWal(pPager)==0 );
+ if( pPg->pgno<=pPager->dbOrigSize && isOpen(pPager->jfd) ){
+ u32 cksum;
+ char *pData2;
+ i64 iOff = pPager->journalOff;
+
+ /* We should never write to the journal file the page that
+ ** contains the database locks. The following assert verifies
+ ** that we do not. */
+ assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
+
+ assert( pPager->journalHdr<=pPager->journalOff );
+ CODEC2(pPager, pPg->pData, pPg->pgno, 7, return SQLITE_NOMEM, pData2);
+ cksum = pager_cksum(pPager, (u8*)pData2);
+
+ /* Even if an IO or diskfull error occurs while journalling the
+ ** page in the block above, set the need-sync flag for the page.
+ ** Otherwise, when the transaction is rolled back, the logic in
+ ** playback_one_page() will think that the page needs to be restored
+ ** in the database file. And if an IO error occurs while doing so,
+ ** then corruption may follow.
+ */
+ pPg->flags |= PGHDR_NEED_SYNC;
+
+ rc = write32bits(pPager->jfd, iOff, pPg->pgno);
+ if( rc!=SQLITE_OK ) return rc;
+ rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize, iOff+4);
+ if( rc!=SQLITE_OK ) return rc;
+ rc = write32bits(pPager->jfd, iOff+pPager->pageSize+4, cksum);
+ if( rc!=SQLITE_OK ) return rc;
+
+ IOTRACE(("JOUT %p %d %lld %d\n", pPager, pPg->pgno,
+ pPager->journalOff, pPager->pageSize));
+ PAGER_INCR(sqlite3_pager_writej_count);
+ PAGERTRACE(("JOURNAL %d page %d needSync=%d hash(%08x)\n",
+ PAGERID(pPager), pPg->pgno,
+ ((pPg->flags&PGHDR_NEED_SYNC)?1:0), pager_pagehash(pPg)));
+
+ pPager->journalOff += 8 + pPager->pageSize;
+ pPager->nRec++;
+ assert( pPager->pInJournal!=0 );
+ rc = sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
+ testcase( rc==SQLITE_NOMEM );
+ assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
+ rc |= addToSavepointBitvecs(pPager, pPg->pgno);
+ if( rc!=SQLITE_OK ){
+ assert( rc==SQLITE_NOMEM );
+ return rc;
+ }
+ }else{
+ if( pPager->eState!=PAGER_WRITER_DBMOD ){
+ pPg->flags |= PGHDR_NEED_SYNC;
+ }
+ PAGERTRACE(("APPEND %d page %d needSync=%d\n",
+ PAGERID(pPager), pPg->pgno,
+ ((pPg->flags&PGHDR_NEED_SYNC)?1:0)));
+ }
+ }
+
+ /* If the statement journal is open and the page is not in it,
+ ** then write the current page to the statement journal. Note that
+ ** the statement journal format differs from the standard journal format
+ ** in that it omits the checksums and the header.
+ */
+ if( pPager->nSavepoint>0 && subjRequiresPage(pPg) ){
+ rc = subjournalPage(pPg);
+ }
+ }
+
+ /* Update the database size and return.
+ */
+ if( pPager->dbSizepgno ){
+ pPager->dbSize = pPg->pgno;
+ }
+ return rc;
+}
+
+/*
+** Mark a data page as writeable. This routine must be called before
+** making changes to a page. The caller must check the return value
+** of this function and be careful not to change any page data unless
+** this routine returns SQLITE_OK.
+**
+** The difference between this function and pager_write() is that this
+** function also deals with the special case where 2 or more pages
+** fit on a single disk sector. In this case all co-resident pages
+** must have been written to the journal file before returning.
+**
+** If an error occurs, SQLITE_NOMEM or an IO error code is returned
+** as appropriate. Otherwise, SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3PagerWrite(DbPage *pDbPage){
+ int rc = SQLITE_OK;
+
+ PgHdr *pPg = pDbPage;
+ Pager *pPager = pPg->pPager;
+
+ assert( (pPg->flags & PGHDR_MMAP)==0 );
+ assert( pPager->eState>=PAGER_WRITER_LOCKED );
+ assert( pPager->eState!=PAGER_ERROR );
+ assert( assert_pager_state(pPager) );
+
+ if( pPager->sectorSize > (u32)pPager->pageSize ){
+ Pgno nPageCount; /* Total number of pages in database file */
+ Pgno pg1; /* First page of the sector pPg is located on. */
+ int nPage = 0; /* Number of pages starting at pg1 to journal */
+ int ii; /* Loop counter */
+ int needSync = 0; /* True if any page has PGHDR_NEED_SYNC */
+ Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);
+
+ /* Set the doNotSpill NOSYNC bit to 1. This is because we cannot allow
+ ** a journal header to be written between the pages journaled by
+ ** this function.
+ */
+ assert( !MEMDB );
+ assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)==0 );
+ pPager->doNotSpill |= SPILLFLAG_NOSYNC;
+
+ /* This trick assumes that both the page-size and sector-size are
+ ** an integer power of 2. It sets variable pg1 to the identifier
+ ** of the first page of the sector pPg is located on.
+ */
+ pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;
+
+ nPageCount = pPager->dbSize;
+ if( pPg->pgno>nPageCount ){
+ nPage = (pPg->pgno - pg1)+1;
+ }else if( (pg1+nPagePerSector-1)>nPageCount ){
+ nPage = nPageCount+1-pg1;
+ }else{
+ nPage = nPagePerSector;
+ }
+ assert(nPage>0);
+ assert(pg1<=pPg->pgno);
+ assert((pg1+nPage)>pPg->pgno);
+
+ for(ii=0; iipgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){
+ if( pg!=PAGER_MJ_PGNO(pPager) ){
+ rc = sqlite3PagerGet(pPager, pg, &pPage);
+ if( rc==SQLITE_OK ){
+ rc = pager_write(pPage);
+ if( pPage->flags&PGHDR_NEED_SYNC ){
+ needSync = 1;
+ }
+ sqlite3PagerUnrefNotNull(pPage);
+ }
+ }
+ }else if( (pPage = pager_lookup(pPager, pg))!=0 ){
+ if( pPage->flags&PGHDR_NEED_SYNC ){
+ needSync = 1;
+ }
+ sqlite3PagerUnrefNotNull(pPage);
+ }
+ }
+
+ /* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages
+ ** starting at pg1, then it needs to be set for all of them. Because
+ ** writing to any of these nPage pages may damage the others, the
+ ** journal file must contain sync()ed copies of all of them
+ ** before any of them can be written out to the database file.
+ */
+ if( rc==SQLITE_OK && needSync ){
+ assert( !MEMDB );
+ for(ii=0; iiflags |= PGHDR_NEED_SYNC;
+ sqlite3PagerUnrefNotNull(pPage);
+ }
+ }
+ }
+
+ assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)!=0 );
+ pPager->doNotSpill &= ~SPILLFLAG_NOSYNC;
+ }else{
+ rc = pager_write(pDbPage);
+ }
+ return rc;
+}
+
+/*
+** Return TRUE if the page given in the argument was previously passed
+** to sqlite3PagerWrite(). In other words, return TRUE if it is ok
+** to change the content of the page.
+*/
+#ifndef NDEBUG
+SQLITE_PRIVATE int sqlite3PagerIswriteable(DbPage *pPg){
+ return pPg->flags&PGHDR_DIRTY;
+}
+#endif
+
+/*
+** A call to this routine tells the pager that it is not necessary to
+** write the information on page pPg back to the disk, even though
+** that page might be marked as dirty. This happens, for example, when
+** the page has been added as a leaf of the freelist and so its
+** content no longer matters.
+**
+** The overlying software layer calls this routine when all of the data
+** on the given page is unused. The pager marks the page as clean so
+** that it does not get written to disk.
+**
+** Tests show that this optimization can quadruple the speed of large
+** DELETE operations.
+*/
+SQLITE_PRIVATE void sqlite3PagerDontWrite(PgHdr *pPg){
+ Pager *pPager = pPg->pPager;
+ if( (pPg->flags&PGHDR_DIRTY) && pPager->nSavepoint==0 ){
+ PAGERTRACE(("DONT_WRITE page %d of %d\n", pPg->pgno, PAGERID(pPager)));
+ IOTRACE(("CLEAN %p %d\n", pPager, pPg->pgno))
+ pPg->flags |= PGHDR_DONT_WRITE;
+ pager_set_pagehash(pPg);
+ }
+}
+
+/*
+** This routine is called to increment the value of the database file
+** change-counter, stored as a 4-byte big-endian integer starting at
+** byte offset 24 of the pager file. The secondary change counter at
+** 92 is also updated, as is the SQLite version number at offset 96.
+**
+** But this only happens if the pPager->changeCountDone flag is false.
+** To avoid excess churning of page 1, the update only happens once.
+** See also the pager_write_changecounter() routine that does an
+** unconditional update of the change counters.
+**
+** If the isDirectMode flag is zero, then this is done by calling
+** sqlite3PagerWrite() on page 1, then modifying the contents of the
+** page data. In this case the file will be updated when the current
+** transaction is committed.
+**
+** The isDirectMode flag may only be non-zero if the library was compiled
+** with the SQLITE_ENABLE_ATOMIC_WRITE macro defined. In this case,
+** if isDirect is non-zero, then the database file is updated directly
+** by writing an updated version of page 1 using a call to the
+** sqlite3OsWrite() function.
+*/
+static int pager_incr_changecounter(Pager *pPager, int isDirectMode){
+ int rc = SQLITE_OK;
+
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* Declare and initialize constant integer 'isDirect'. If the
+ ** atomic-write optimization is enabled in this build, then isDirect
+ ** is initialized to the value passed as the isDirectMode parameter
+ ** to this function. Otherwise, it is always set to zero.
+ **
+ ** The idea is that if the atomic-write optimization is not
+ ** enabled at compile time, the compiler can omit the tests of
+ ** 'isDirect' below, as well as the block enclosed in the
+ ** "if( isDirect )" condition.
+ */
+#ifndef SQLITE_ENABLE_ATOMIC_WRITE
+# define DIRECT_MODE 0
+ assert( isDirectMode==0 );
+ UNUSED_PARAMETER(isDirectMode);
+#else
+# define DIRECT_MODE isDirectMode
+#endif
+
+ if( !pPager->changeCountDone && ALWAYS(pPager->dbSize>0) ){
+ PgHdr *pPgHdr; /* Reference to page 1 */
+
+ assert( !pPager->tempFile && isOpen(pPager->fd) );
+
+ /* Open page 1 of the file for writing. */
+ rc = sqlite3PagerGet(pPager, 1, &pPgHdr);
+ assert( pPgHdr==0 || rc==SQLITE_OK );
+
+ /* If page one was fetched successfully, and this function is not
+ ** operating in direct-mode, make page 1 writable. When not in
+ ** direct mode, page 1 is always held in cache and hence the PagerGet()
+ ** above is always successful - hence the ALWAYS on rc==SQLITE_OK.
+ */
+ if( !DIRECT_MODE && ALWAYS(rc==SQLITE_OK) ){
+ rc = sqlite3PagerWrite(pPgHdr);
+ }
+
+ if( rc==SQLITE_OK ){
+ /* Actually do the update of the change counter */
+ pager_write_changecounter(pPgHdr);
+
+ /* If running in direct mode, write the contents of page 1 to the file. */
+ if( DIRECT_MODE ){
+ const void *zBuf;
+ assert( pPager->dbFileSize>0 );
+ CODEC2(pPager, pPgHdr->pData, 1, 6, rc=SQLITE_NOMEM, zBuf);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsWrite(pPager->fd, zBuf, pPager->pageSize, 0);
+ pPager->aStat[PAGER_STAT_WRITE]++;
+ }
+ if( rc==SQLITE_OK ){
+ /* Update the pager's copy of the change-counter. Otherwise, the
+ ** next time a read transaction is opened the cache will be
+ ** flushed (as the change-counter values will not match). */
+ const void *pCopy = (const void *)&((const char *)zBuf)[24];
+ memcpy(&pPager->dbFileVers, pCopy, sizeof(pPager->dbFileVers));
+ pPager->changeCountDone = 1;
+ }
+ }else{
+ pPager->changeCountDone = 1;
+ }
+ }
+
+ /* Release the page reference. */
+ sqlite3PagerUnref(pPgHdr);
+ }
+ return rc;
+}
+
+/*
+** Sync the database file to disk. This is a no-op for in-memory databases
+** or pages with the Pager.noSync flag set.
+**
+** If successful, or if called on a pager for which it is a no-op, this
+** function returns SQLITE_OK. Otherwise, an IO error code is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager, const char *zMaster){
+ int rc = SQLITE_OK;
+
+ if( isOpen(pPager->fd) ){
+ void *pArg = (void*)zMaster;
+ rc = sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_SYNC, pArg);
+ if( rc==SQLITE_NOTFOUND ) rc = SQLITE_OK;
+ }
+ if( rc==SQLITE_OK && !pPager->noSync ){
+ assert( !MEMDB );
+ rc = sqlite3OsSync(pPager->fd, pPager->syncFlags);
+ }
+ return rc;
+}
+
+/*
+** This function may only be called while a write-transaction is active in
+** rollback. If the connection is in WAL mode, this call is a no-op.
+** Otherwise, if the connection does not already have an EXCLUSIVE lock on
+** the database file, an attempt is made to obtain one.
+**
+** If the EXCLUSIVE lock is already held or the attempt to obtain it is
+** successful, or the connection is in WAL mode, SQLITE_OK is returned.
+** Otherwise, either SQLITE_BUSY or an SQLITE_IOERR_XXX error code is
+** returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager *pPager){
+ int rc = SQLITE_OK;
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ || pPager->eState==PAGER_WRITER_LOCKED
+ );
+ assert( assert_pager_state(pPager) );
+ if( 0==pagerUseWal(pPager) ){
+ rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+ }
+ return rc;
+}
+
+/*
+** Sync the database file for the pager pPager. zMaster points to the name
+** of a master journal file that should be written into the individual
+** journal file. zMaster may be NULL, which is interpreted as no master
+** journal (a single database transaction).
+**
+** This routine ensures that:
+**
+** * The database file change-counter is updated,
+** * the journal is synced (unless the atomic-write optimization is used),
+** * all dirty pages are written to the database file,
+** * the database file is truncated (if required), and
+** * the database file synced.
+**
+** The only thing that remains to commit the transaction is to finalize
+** (delete, truncate or zero the first part of) the journal file (or
+** delete the master journal file if specified).
+**
+** Note that if zMaster==NULL, this does not overwrite a previous value
+** passed to an sqlite3PagerCommitPhaseOne() call.
+**
+** If the final parameter - noSync - is true, then the database file itself
+** is not synced. The caller must call sqlite3PagerSync() directly to
+** sync the database file before calling CommitPhaseTwo() to delete the
+** journal file in this case.
+*/
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(
+ Pager *pPager, /* Pager object */
+ const char *zMaster, /* If not NULL, the master journal name */
+ int noSync /* True to omit the xSync on the db file */
+){
+ int rc = SQLITE_OK; /* Return code */
+
+ assert( pPager->eState==PAGER_WRITER_LOCKED
+ || pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ || pPager->eState==PAGER_ERROR
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* If a prior error occurred, report that error again. */
+ if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+ PAGERTRACE(("DATABASE SYNC: File=%s zMaster=%s nSize=%d\n",
+ pPager->zFilename, zMaster, pPager->dbSize));
+
+ /* If no database changes have been made, return early. */
+ if( pPager->eStatepBackup);
+ }else{
+ if( pagerUseWal(pPager) ){
+ PgHdr *pList = sqlite3PcacheDirtyList(pPager->pPCache);
+ PgHdr *pPageOne = 0;
+ if( pList==0 ){
+ /* Must have at least one page for the WAL commit flag.
+ ** Ticket [2d1a5c67dfc2363e44f29d9bbd57f] 2011-05-18 */
+ rc = sqlite3PagerGet(pPager, 1, &pPageOne);
+ pList = pPageOne;
+ pList->pDirty = 0;
+ }
+ assert( rc==SQLITE_OK );
+ if( ALWAYS(pList) ){
+ rc = pagerWalFrames(pPager, pList, pPager->dbSize, 1);
+ }
+ sqlite3PagerUnref(pPageOne);
+ if( rc==SQLITE_OK ){
+ sqlite3PcacheCleanAll(pPager->pPCache);
+ }
+ }else{
+ /* The following block updates the change-counter. Exactly how it
+ ** does this depends on whether or not the atomic-update optimization
+ ** was enabled at compile time, and if this transaction meets the
+ ** runtime criteria to use the operation:
+ **
+ ** * The file-system supports the atomic-write property for
+ ** blocks of size page-size, and
+ ** * This commit is not part of a multi-file transaction, and
+ ** * Exactly one page has been modified and store in the journal file.
+ **
+ ** If the optimization was not enabled at compile time, then the
+ ** pager_incr_changecounter() function is called to update the change
+ ** counter in 'indirect-mode'. If the optimization is compiled in but
+ ** is not applicable to this transaction, call sqlite3JournalCreate()
+ ** to make sure the journal file has actually been created, then call
+ ** pager_incr_changecounter() to update the change-counter in indirect
+ ** mode.
+ **
+ ** Otherwise, if the optimization is both enabled and applicable,
+ ** then call pager_incr_changecounter() to update the change-counter
+ ** in 'direct' mode. In this case the journal file will never be
+ ** created for this transaction.
+ */
+ #ifdef SQLITE_ENABLE_ATOMIC_WRITE
+ PgHdr *pPg;
+ assert( isOpen(pPager->jfd)
+ || pPager->journalMode==PAGER_JOURNALMODE_OFF
+ || pPager->journalMode==PAGER_JOURNALMODE_WAL
+ );
+ if( !zMaster && isOpen(pPager->jfd)
+ && pPager->journalOff==jrnlBufferSize(pPager)
+ && pPager->dbSize>=pPager->dbOrigSize
+ && (0==(pPg = sqlite3PcacheDirtyList(pPager->pPCache)) || 0==pPg->pDirty)
+ ){
+ /* Update the db file change counter via the direct-write method. The
+ ** following call will modify the in-memory representation of page 1
+ ** to include the updated change counter and then write page 1
+ ** directly to the database file. Because of the atomic-write
+ ** property of the host file-system, this is safe.
+ */
+ rc = pager_incr_changecounter(pPager, 1);
+ }else{
+ rc = sqlite3JournalCreate(pPager->jfd);
+ if( rc==SQLITE_OK ){
+ rc = pager_incr_changecounter(pPager, 0);
+ }
+ }
+ #else
+ rc = pager_incr_changecounter(pPager, 0);
+ #endif
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+ /* Write the master journal name into the journal file. If a master
+ ** journal file name has already been written to the journal file,
+ ** or if zMaster is NULL (no master journal), then this call is a no-op.
+ */
+ rc = writeMasterJournal(pPager, zMaster);
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+ /* Sync the journal file and write all dirty pages to the database.
+ ** If the atomic-update optimization is being used, this sync will not
+ ** create the journal file or perform any real IO.
+ **
+ ** Because the change-counter page was just modified, unless the
+ ** atomic-update optimization is used it is almost certain that the
+ ** journal requires a sync here. However, in locking_mode=exclusive
+ ** on a system under memory pressure it is just possible that this is
+ ** not the case. In this case it is likely enough that the redundant
+ ** xSync() call will be changed to a no-op by the OS anyhow.
+ */
+ rc = syncJournal(pPager, 0);
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+
+ rc = pager_write_pagelist(pPager,sqlite3PcacheDirtyList(pPager->pPCache));
+ if( rc!=SQLITE_OK ){
+ assert( rc!=SQLITE_IOERR_BLOCKED );
+ goto commit_phase_one_exit;
+ }
+ sqlite3PcacheCleanAll(pPager->pPCache);
+
+ /* If the file on disk is smaller than the database image, use
+ ** pager_truncate to grow the file here. This can happen if the database
+ ** image was extended as part of the current transaction and then the
+ ** last page in the db image moved to the free-list. In this case the
+ ** last page is never written out to disk, leaving the database file
+ ** undersized. Fix this now if it is the case. */
+ if( pPager->dbSize>pPager->dbFileSize ){
+ Pgno nNew = pPager->dbSize - (pPager->dbSize==PAGER_MJ_PGNO(pPager));
+ assert( pPager->eState==PAGER_WRITER_DBMOD );
+ rc = pager_truncate(pPager, nNew);
+ if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
+ }
+
+ /* Finally, sync the database file. */
+ if( !noSync ){
+ rc = sqlite3PagerSync(pPager, zMaster);
+ }
+ IOTRACE(("DBSYNC %p\n", pPager))
+ }
+ }
+
+commit_phase_one_exit:
+ if( rc==SQLITE_OK && !pagerUseWal(pPager) ){
+ pPager->eState = PAGER_WRITER_FINISHED;
+ }
+ return rc;
+}
+
+
+/*
+** When this function is called, the database file has been completely
+** updated to reflect the changes made by the current transaction and
+** synced to disk. The journal file still exists in the file-system
+** though, and if a failure occurs at this point it will eventually
+** be used as a hot-journal and the current transaction rolled back.
+**
+** This function finalizes the journal file, either by deleting,
+** truncating or partially zeroing it, so that it cannot be used
+** for hot-journal rollback. Once this is done the transaction is
+** irrevocably committed.
+**
+** If an error occurs, an IO error code is returned and the pager
+** moves into the error state. Otherwise, SQLITE_OK is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+
+ /* This routine should not be called if a prior error has occurred.
+ ** But if (due to a coding error elsewhere in the system) it does get
+ ** called, just return the same error code without doing anything. */
+ if( NEVER(pPager->errCode) ) return pPager->errCode;
+
+ assert( pPager->eState==PAGER_WRITER_LOCKED
+ || pPager->eState==PAGER_WRITER_FINISHED
+ || (pagerUseWal(pPager) && pPager->eState==PAGER_WRITER_CACHEMOD)
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* An optimization. If the database was not actually modified during
+ ** this transaction, the pager is running in exclusive-mode and is
+ ** using persistent journals, then this function is a no-op.
+ **
+ ** The start of the journal file currently contains a single journal
+ ** header with the nRec field set to 0. If such a journal is used as
+ ** a hot-journal during hot-journal rollback, 0 changes will be made
+ ** to the database file. So there is no need to zero the journal
+ ** header. Since the pager is in exclusive mode, there is no need
+ ** to drop any locks either.
+ */
+ if( pPager->eState==PAGER_WRITER_LOCKED
+ && pPager->exclusiveMode
+ && pPager->journalMode==PAGER_JOURNALMODE_PERSIST
+ ){
+ assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) || !pPager->journalOff );
+ pPager->eState = PAGER_READER;
+ return SQLITE_OK;
+ }
+
+ PAGERTRACE(("COMMIT %d\n", PAGERID(pPager)));
+ rc = pager_end_transaction(pPager, pPager->setMaster, 1);
+ return pager_error(pPager, rc);
+}
+
+/*
+** If a write transaction is open, then all changes made within the
+** transaction are reverted and the current write-transaction is closed.
+** The pager falls back to PAGER_READER state if successful, or PAGER_ERROR
+** state if an error occurs.
+**
+** If the pager is already in PAGER_ERROR state when this function is called,
+** it returns Pager.errCode immediately. No work is performed in this case.
+**
+** Otherwise, in rollback mode, this function performs two functions:
+**
+** 1) It rolls back the journal file, restoring all database file and
+** in-memory cache pages to the state they were in when the transaction
+** was opened, and
+**
+** 2) It finalizes the journal file, so that it is not used for hot
+** rollback at any point in the future.
+**
+** Finalization of the journal file (task 2) is only performed if the
+** rollback is successful.
+**
+** In WAL mode, all cache-entries containing data modified within the
+** current transaction are either expelled from the cache or reverted to
+** their pre-transaction state by re-reading data from the database or
+** WAL files. The WAL transaction is then closed.
+*/
+SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
+ int rc = SQLITE_OK; /* Return code */
+ PAGERTRACE(("ROLLBACK %d\n", PAGERID(pPager)));
+
+ /* PagerRollback() is a no-op if called in READER or OPEN state. If
+ ** the pager is already in the ERROR state, the rollback is not
+ ** attempted here. Instead, the error code is returned to the caller.
+ */
+ assert( assert_pager_state(pPager) );
+ if( pPager->eState==PAGER_ERROR ) return pPager->errCode;
+ if( pPager->eState<=PAGER_READER ) return SQLITE_OK;
+
+ if( pagerUseWal(pPager) ){
+ int rc2;
+ rc = sqlite3PagerSavepoint(pPager, SAVEPOINT_ROLLBACK, -1);
+ rc2 = pager_end_transaction(pPager, pPager->setMaster, 0);
+ if( rc==SQLITE_OK ) rc = rc2;
+ }else if( !isOpen(pPager->jfd) || pPager->eState==PAGER_WRITER_LOCKED ){
+ int eState = pPager->eState;
+ rc = pager_end_transaction(pPager, 0, 0);
+ if( !MEMDB && eState>PAGER_WRITER_LOCKED ){
+ /* This can happen using journal_mode=off. Move the pager to the error
+ ** state to indicate that the contents of the cache may not be trusted.
+ ** Any active readers will get SQLITE_ABORT.
+ */
+ pPager->errCode = SQLITE_ABORT;
+ pPager->eState = PAGER_ERROR;
+ return rc;
+ }
+ }else{
+ rc = pager_playback(pPager, 0);
+ }
+
+ assert( pPager->eState==PAGER_READER || rc!=SQLITE_OK );
+ assert( rc==SQLITE_OK || rc==SQLITE_FULL || rc==SQLITE_CORRUPT
+ || rc==SQLITE_NOMEM || (rc&0xFF)==SQLITE_IOERR
+ || rc==SQLITE_CANTOPEN
+ );
+
+ /* If an error occurs during a ROLLBACK, we can no longer trust the pager
+ ** cache. So call pager_error() on the way out to make any error persistent.
+ */
+ return pager_error(pPager, rc);
+}
+
+/*
+** Return TRUE if the database file is opened read-only. Return FALSE
+** if the database is (in theory) writable.
+*/
+SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager *pPager){
+ return pPager->readOnly;
+}
+
+/*
+** Return the number of references to the pager.
+*/
+SQLITE_PRIVATE int sqlite3PagerRefcount(Pager *pPager){
+ return sqlite3PcacheRefCount(pPager->pPCache);
+}
+
+/*
+** Return the approximate number of bytes of memory currently
+** used by the pager and its associated cache.
+*/
+SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager *pPager){
+ int perPageSize = pPager->pageSize + pPager->nExtra + sizeof(PgHdr)
+ + 5*sizeof(void*);
+ return perPageSize*sqlite3PcachePagecount(pPager->pPCache)
+ + sqlite3MallocSize(pPager)
+ + pPager->pageSize;
+}
+
+/*
+** Return the number of references to the specified page.
+*/
+SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage *pPage){
+ return sqlite3PcachePageRefcount(pPage);
+}
+
+#ifdef SQLITE_TEST
+/*
+** This routine is used for testing and analysis only.
+*/
+SQLITE_PRIVATE int *sqlite3PagerStats(Pager *pPager){
+ static int a[11];
+ a[0] = sqlite3PcacheRefCount(pPager->pPCache);
+ a[1] = sqlite3PcachePagecount(pPager->pPCache);
+ a[2] = sqlite3PcacheGetCachesize(pPager->pPCache);
+ a[3] = pPager->eState==PAGER_OPEN ? -1 : (int) pPager->dbSize;
+ a[4] = pPager->eState;
+ a[5] = pPager->errCode;
+ a[6] = pPager->aStat[PAGER_STAT_HIT];
+ a[7] = pPager->aStat[PAGER_STAT_MISS];
+ a[8] = 0; /* Used to be pPager->nOvfl */
+ a[9] = pPager->nRead;
+ a[10] = pPager->aStat[PAGER_STAT_WRITE];
+ return a;
+}
+#endif
+
+/*
+** Parameter eStat must be either SQLITE_DBSTATUS_CACHE_HIT or
+** SQLITE_DBSTATUS_CACHE_MISS. Before returning, *pnVal is incremented by the
+** current cache hit or miss count, according to the value of eStat. If the
+** reset parameter is non-zero, the cache hit or miss count is zeroed before
+** returning.
+*/
+SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *pPager, int eStat, int reset, int *pnVal){
+
+ assert( eStat==SQLITE_DBSTATUS_CACHE_HIT
+ || eStat==SQLITE_DBSTATUS_CACHE_MISS
+ || eStat==SQLITE_DBSTATUS_CACHE_WRITE
+ );
+
+ assert( SQLITE_DBSTATUS_CACHE_HIT+1==SQLITE_DBSTATUS_CACHE_MISS );
+ assert( SQLITE_DBSTATUS_CACHE_HIT+2==SQLITE_DBSTATUS_CACHE_WRITE );
+ assert( PAGER_STAT_HIT==0 && PAGER_STAT_MISS==1 && PAGER_STAT_WRITE==2 );
+
+ *pnVal += pPager->aStat[eStat - SQLITE_DBSTATUS_CACHE_HIT];
+ if( reset ){
+ pPager->aStat[eStat - SQLITE_DBSTATUS_CACHE_HIT] = 0;
+ }
+}
+
+/*
+** Return true if this is an in-memory pager.
+*/
+SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager *pPager){
+ return MEMDB;
+}
+
+/*
+** Check that there are at least nSavepoint savepoints open. If there are
+** currently less than nSavepoints open, then open one or more savepoints
+** to make up the difference. If the number of savepoints is already
+** equal to nSavepoint, then this function is a no-op.
+**
+** If a memory allocation fails, SQLITE_NOMEM is returned. If an error
+** occurs while opening the sub-journal file, then an IO error code is
+** returned. Otherwise, SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int nSavepoint){
+ int rc = SQLITE_OK; /* Return code */
+ int nCurrent = pPager->nSavepoint; /* Current number of savepoints */
+
+ assert( pPager->eState>=PAGER_WRITER_LOCKED );
+ assert( assert_pager_state(pPager) );
+
+ if( nSavepoint>nCurrent && pPager->useJournal ){
+ int ii; /* Iterator variable */
+ PagerSavepoint *aNew; /* New Pager.aSavepoint array */
+
+ /* Grow the Pager.aSavepoint array using realloc(). Return SQLITE_NOMEM
+ ** if the allocation fails. Otherwise, zero the new portion in case a
+ ** malloc failure occurs while populating it in the for(...) loop below.
+ */
+ aNew = (PagerSavepoint *)sqlite3Realloc(
+ pPager->aSavepoint, sizeof(PagerSavepoint)*nSavepoint
+ );
+ if( !aNew ){
+ return SQLITE_NOMEM;
+ }
+ memset(&aNew[nCurrent], 0, (nSavepoint-nCurrent) * sizeof(PagerSavepoint));
+ pPager->aSavepoint = aNew;
+
+ /* Populate the PagerSavepoint structures just allocated. */
+ for(ii=nCurrent; iidbSize;
+ if( isOpen(pPager->jfd) && pPager->journalOff>0 ){
+ aNew[ii].iOffset = pPager->journalOff;
+ }else{
+ aNew[ii].iOffset = JOURNAL_HDR_SZ(pPager);
+ }
+ aNew[ii].iSubRec = pPager->nSubRec;
+ aNew[ii].pInSavepoint = sqlite3BitvecCreate(pPager->dbSize);
+ if( !aNew[ii].pInSavepoint ){
+ return SQLITE_NOMEM;
+ }
+ if( pagerUseWal(pPager) ){
+ sqlite3WalSavepoint(pPager->pWal, aNew[ii].aWalData);
+ }
+ pPager->nSavepoint = ii+1;
+ }
+ assert( pPager->nSavepoint==nSavepoint );
+ assertTruncateConstraint(pPager);
+ }
+
+ return rc;
+}
+
+/*
+** This function is called to rollback or release (commit) a savepoint.
+** The savepoint to release or rollback need not be the most recently
+** created savepoint.
+**
+** Parameter op is always either SAVEPOINT_ROLLBACK or SAVEPOINT_RELEASE.
+** If it is SAVEPOINT_RELEASE, then release and destroy the savepoint with
+** index iSavepoint. If it is SAVEPOINT_ROLLBACK, then rollback all changes
+** that have occurred since the specified savepoint was created.
+**
+** The savepoint to rollback or release is identified by parameter
+** iSavepoint. A value of 0 means to operate on the outermost savepoint
+** (the first created). A value of (Pager.nSavepoint-1) means operate
+** on the most recently created savepoint. If iSavepoint is greater than
+** (Pager.nSavepoint-1), then this function is a no-op.
+**
+** If a negative value is passed to this function, then the current
+** transaction is rolled back. This is different to calling
+** sqlite3PagerRollback() because this function does not terminate
+** the transaction or unlock the database, it just restores the
+** contents of the database to its original state.
+**
+** In any case, all savepoints with an index greater than iSavepoint
+** are destroyed. If this is a release operation (op==SAVEPOINT_RELEASE),
+** then savepoint iSavepoint is also destroyed.
+**
+** This function may return SQLITE_NOMEM if a memory allocation fails,
+** or an IO error code if an IO error occurs while rolling back a
+** savepoint. If no errors occur, SQLITE_OK is returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint){
+ int rc = pPager->errCode; /* Return code */
+
+ assert( op==SAVEPOINT_RELEASE || op==SAVEPOINT_ROLLBACK );
+ assert( iSavepoint>=0 || op==SAVEPOINT_ROLLBACK );
+
+ if( rc==SQLITE_OK && iSavepointnSavepoint ){
+ int ii; /* Iterator variable */
+ int nNew; /* Number of remaining savepoints after this op. */
+
+ /* Figure out how many savepoints will still be active after this
+ ** operation. Store this value in nNew. Then free resources associated
+ ** with any savepoints that are destroyed by this operation.
+ */
+ nNew = iSavepoint + (( op==SAVEPOINT_RELEASE ) ? 0 : 1);
+ for(ii=nNew; iinSavepoint; ii++){
+ sqlite3BitvecDestroy(pPager->aSavepoint[ii].pInSavepoint);
+ }
+ pPager->nSavepoint = nNew;
+
+ /* If this is a release of the outermost savepoint, truncate
+ ** the sub-journal to zero bytes in size. */
+ if( op==SAVEPOINT_RELEASE ){
+ if( nNew==0 && isOpen(pPager->sjfd) ){
+ /* Only truncate if it is an in-memory sub-journal. */
+ if( sqlite3IsMemJournal(pPager->sjfd) ){
+ rc = sqlite3OsTruncate(pPager->sjfd, 0);
+ assert( rc==SQLITE_OK );
+ }
+ pPager->nSubRec = 0;
+ }
+ }
+ /* Else this is a rollback operation, playback the specified savepoint.
+ ** If this is a temp-file, it is possible that the journal file has
+ ** not yet been opened. In this case there have been no changes to
+ ** the database file, so the playback operation can be skipped.
+ */
+ else if( pagerUseWal(pPager) || isOpen(pPager->jfd) ){
+ PagerSavepoint *pSavepoint = (nNew==0)?0:&pPager->aSavepoint[nNew-1];
+ rc = pagerPlaybackSavepoint(pPager, pSavepoint);
+ assert(rc!=SQLITE_DONE);
+ }
+ }
+
+ return rc;
+}
+
+/*
+** Return the full pathname of the database file.
+**
+** Except, if the pager is in-memory only, then return an empty string if
+** nullIfMemDb is true. This routine is called with nullIfMemDb==1 when
+** used to report the filename to the user, for compatibility with legacy
+** behavior. But when the Btree needs to know the filename for matching to
+** shared cache, it uses nullIfMemDb==0 so that in-memory databases can
+** participate in shared-cache.
+*/
+SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager *pPager, int nullIfMemDb){
+ return (nullIfMemDb && pPager->memDb) ? "" : pPager->zFilename;
+}
+
+/*
+** Return the VFS structure for the pager.
+*/
+SQLITE_PRIVATE const sqlite3_vfs *sqlite3PagerVfs(Pager *pPager){
+ return pPager->pVfs;
+}
+
+/*
+** Return the file handle for the database file associated
+** with the pager. This might return NULL if the file has
+** not yet been opened.
+*/
+SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager *pPager){
+ return pPager->fd;
+}
+
+/*
+** Return the full pathname of the journal file.
+*/
+SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager *pPager){
+ return pPager->zJournal;
+}
+
+/*
+** Return true if fsync() calls are disabled for this pager. Return FALSE
+** if fsync()s are executed normally.
+*/
+SQLITE_PRIVATE int sqlite3PagerNosync(Pager *pPager){
+ return pPager->noSync;
+}
+
+#ifdef SQLITE_HAS_CODEC
+/*
+** Set or retrieve the codec for this pager
+*/
+SQLITE_PRIVATE void sqlite3PagerSetCodec(
+ Pager *pPager,
+ void *(*xCodec)(void*,void*,Pgno,int),
+ void (*xCodecSizeChng)(void*,int,int),
+ void (*xCodecFree)(void*),
+ void *pCodec
+){
+ if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
+ pPager->xCodec = pPager->memDb ? 0 : xCodec;
+ pPager->xCodecSizeChng = xCodecSizeChng;
+ pPager->xCodecFree = xCodecFree;
+ pPager->pCodec = pCodec;
+ pagerReportSize(pPager);
+}
+SQLITE_PRIVATE void *sqlite3PagerGetCodec(Pager *pPager){
+ return pPager->pCodec;
+}
+
+/*
+** This function is called by the wal module when writing page content
+** into the log file.
+**
+** This function returns a pointer to a buffer containing the encrypted
+** page content. If a malloc fails, this function may return NULL.
+*/
+SQLITE_PRIVATE void *sqlite3PagerCodec(PgHdr *pPg){
+ void *aData = 0;
+ CODEC2(pPg->pPager, pPg->pData, pPg->pgno, 6, return 0, aData);
+ return aData;
+}
+
+/*
+** Return the current pager state
+*/
+SQLITE_PRIVATE int sqlite3PagerState(Pager *pPager){
+ return pPager->eState;
+}
+#endif /* SQLITE_HAS_CODEC */
+
+#ifndef SQLITE_OMIT_AUTOVACUUM
+/*
+** Move the page pPg to location pgno in the file.
+**
+** There must be no references to the page previously located at
+** pgno (which we call pPgOld) though that page is allowed to be
+** in cache. If the page previously located at pgno is not already
+** in the rollback journal, it is not put there by by this routine.
+**
+** References to the page pPg remain valid. Updating any
+** meta-data associated with pPg (i.e. data stored in the nExtra bytes
+** allocated along with the page) is the responsibility of the caller.
+**
+** A transaction must be active when this routine is called. It used to be
+** required that a statement transaction was not active, but this restriction
+** has been removed (CREATE INDEX needs to move a page when a statement
+** transaction is active).
+**
+** If the fourth argument, isCommit, is non-zero, then this page is being
+** moved as part of a database reorganization just before the transaction
+** is being committed. In this case, it is guaranteed that the database page
+** pPg refers to will not be written to again within this transaction.
+**
+** This function may return SQLITE_NOMEM or an IO error code if an error
+** occurs. Otherwise, it returns SQLITE_OK.
+*/
+SQLITE_PRIVATE int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
+ PgHdr *pPgOld; /* The page being overwritten. */
+ Pgno needSyncPgno = 0; /* Old value of pPg->pgno, if sync is required */
+ int rc; /* Return code */
+ Pgno origPgno; /* The original page number */
+
+ assert( pPg->nRef>0 );
+ assert( pPager->eState==PAGER_WRITER_CACHEMOD
+ || pPager->eState==PAGER_WRITER_DBMOD
+ );
+ assert( assert_pager_state(pPager) );
+
+ /* In order to be able to rollback, an in-memory database must journal
+ ** the page we are moving from.
+ */
+ if( MEMDB ){
+ rc = sqlite3PagerWrite(pPg);
+ if( rc ) return rc;
+ }
+
+ /* If the page being moved is dirty and has not been saved by the latest
+ ** savepoint, then save the current contents of the page into the
+ ** sub-journal now. This is required to handle the following scenario:
+ **
+ ** BEGIN;
+ **
+ ** SAVEPOINT one;
+ **
+ ** ROLLBACK TO one;
+ **
+ ** If page X were not written to the sub-journal here, it would not
+ ** be possible to restore its contents when the "ROLLBACK TO one"
+ ** statement were is processed.
+ **
+ ** subjournalPage() may need to allocate space to store pPg->pgno into
+ ** one or more savepoint bitvecs. This is the reason this function
+ ** may return SQLITE_NOMEM.
+ */
+ if( pPg->flags&PGHDR_DIRTY
+ && subjRequiresPage(pPg)
+ && SQLITE_OK!=(rc = subjournalPage(pPg))
+ ){
+ return rc;
+ }
+
+ PAGERTRACE(("MOVE %d page %d (needSync=%d) moves to %d\n",
+ PAGERID(pPager), pPg->pgno, (pPg->flags&PGHDR_NEED_SYNC)?1:0, pgno));
+ IOTRACE(("MOVE %p %d %d\n", pPager, pPg->pgno, pgno))
+
+ /* If the journal needs to be sync()ed before page pPg->pgno can
+ ** be written to, store pPg->pgno in local variable needSyncPgno.
+ **
+ ** If the isCommit flag is set, there is no need to remember that
+ ** the journal needs to be sync()ed before database page pPg->pgno
+ ** can be written to. The caller has already promised not to write to it.
+ */
+ if( (pPg->flags&PGHDR_NEED_SYNC) && !isCommit ){
+ needSyncPgno = pPg->pgno;
+ assert( pPager->journalMode==PAGER_JOURNALMODE_OFF ||
+ pageInJournal(pPager, pPg) || pPg->pgno>pPager->dbOrigSize );
+ assert( pPg->flags&PGHDR_DIRTY );
+ }
+
+ /* If the cache contains a page with page-number pgno, remove it
+ ** from its hash chain. Also, if the PGHDR_NEED_SYNC flag was set for
+ ** page pgno before the 'move' operation, it needs to be retained
+ ** for the page moved there.
+ */
+ pPg->flags &= ~PGHDR_NEED_SYNC;
+ pPgOld = pager_lookup(pPager, pgno);
+ assert( !pPgOld || pPgOld->nRef==1 );
+ if( pPgOld ){
+ pPg->flags |= (pPgOld->flags&PGHDR_NEED_SYNC);
+ if( MEMDB ){
+ /* Do not discard pages from an in-memory database since we might
+ ** need to rollback later. Just move the page out of the way. */
+ sqlite3PcacheMove(pPgOld, pPager->dbSize+1);
+ }else{
+ sqlite3PcacheDrop(pPgOld);
+ }
+ }
+
+ origPgno = pPg->pgno;
+ sqlite3PcacheMove(pPg, pgno);
+ sqlite3PcacheMakeDirty(pPg);
+
+ /* For an in-memory database, make sure the original page continues
+ ** to exist, in case the transaction needs to roll back. Use pPgOld
+ ** as the original page since it has already been allocated.
+ */
+ if( MEMDB ){
+ assert( pPgOld );
+ sqlite3PcacheMove(pPgOld, origPgno);
+ sqlite3PagerUnrefNotNull(pPgOld);
+ }
+
+ if( needSyncPgno ){
+ /* If needSyncPgno is non-zero, then the journal file needs to be
+ ** sync()ed before any data is written to database file page needSyncPgno.
+ ** Currently, no such page exists in the page-cache and the
+ ** "is journaled" bitvec flag has been set. This needs to be remedied by
+ ** loading the page into the pager-cache and setting the PGHDR_NEED_SYNC
+ ** flag.
+ **
+ ** If the attempt to load the page into the page-cache fails, (due
+ ** to a malloc() or IO failure), clear the bit in the pInJournal[]
+ ** array. Otherwise, if the page is loaded and written again in
+ ** this transaction, it may be written to the database file before
+ ** it is synced into the journal file. This way, it may end up in
+ ** the journal file twice, but that is not a problem.
+ */
+ PgHdr *pPgHdr;
+ rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
+ if( rc!=SQLITE_OK ){
+ if( needSyncPgno<=pPager->dbOrigSize ){
+ assert( pPager->pTmpSpace!=0 );
+ sqlite3BitvecClear(pPager->pInJournal, needSyncPgno, pPager->pTmpSpace);
+ }
+ return rc;
+ }
+ pPgHdr->flags |= PGHDR_NEED_SYNC;
+ sqlite3PcacheMakeDirty(pPgHdr);
+ sqlite3PagerUnrefNotNull(pPgHdr);
+ }
+
+ return SQLITE_OK;
+}
+#endif
+
+/*
+** Return a pointer to the data for the specified page.
+*/
+SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *pPg){
+ assert( pPg->nRef>0 || pPg->pPager->memDb );
+ return pPg->pData;
+}
+
+/*
+** Return a pointer to the Pager.nExtra bytes of "extra" space
+** allocated along with the specified page.
+*/
+SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *pPg){
+ return pPg->pExtra;
+}
+
+/*
+** Get/set the locking-mode for this pager. Parameter eMode must be one
+** of PAGER_LOCKINGMODE_QUERY, PAGER_LOCKINGMODE_NORMAL or
+** PAGER_LOCKINGMODE_EXCLUSIVE. If the parameter is not _QUERY, then
+** the locking-mode is set to the value specified.
+**
+** The returned value is either PAGER_LOCKINGMODE_NORMAL or
+** PAGER_LOCKINGMODE_EXCLUSIVE, indicating the current (possibly updated)
+** locking-mode.
+*/
+SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *pPager, int eMode){
+ assert( eMode==PAGER_LOCKINGMODE_QUERY
+ || eMode==PAGER_LOCKINGMODE_NORMAL
+ || eMode==PAGER_LOCKINGMODE_EXCLUSIVE );
+ assert( PAGER_LOCKINGMODE_QUERY<0 );
+ assert( PAGER_LOCKINGMODE_NORMAL>=0 && PAGER_LOCKINGMODE_EXCLUSIVE>=0 );
+ assert( pPager->exclusiveMode || 0==sqlite3WalHeapMemory(pPager->pWal) );
+ if( eMode>=0 && !pPager->tempFile && !sqlite3WalHeapMemory(pPager->pWal) ){
+ pPager->exclusiveMode = (u8)eMode;
+ }
+ return (int)pPager->exclusiveMode;
+}
+
+/*
+** Set the journal-mode for this pager. Parameter eMode must be one of:
+**
+** PAGER_JOURNALMODE_DELETE
+** PAGER_JOURNALMODE_TRUNCATE
+** PAGER_JOURNALMODE_PERSIST
+** PAGER_JOURNALMODE_OFF
+** PAGER_JOURNALMODE_MEMORY
+** PAGER_JOURNALMODE_WAL
+**
+** The journalmode is set to the value specified if the change is allowed.
+** The change may be disallowed for the following reasons:
+**
+** * An in-memory database can only have its journal_mode set to _OFF
+** or _MEMORY.
+**
+** * Temporary databases cannot have _WAL journalmode.
+**
+** The returned indicate the current (possibly updated) journal-mode.
+*/
+SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *pPager, int eMode){
+ u8 eOld = pPager->journalMode; /* Prior journalmode */
+
+#ifdef SQLITE_DEBUG
+ /* The print_pager_state() routine is intended to be used by the debugger
+ ** only. We invoke it once here to suppress a compiler warning. */
+ print_pager_state(pPager);
+#endif
+
+
+ /* The eMode parameter is always valid */
+ assert( eMode==PAGER_JOURNALMODE_DELETE
+ || eMode==PAGER_JOURNALMODE_TRUNCATE
+ || eMode==PAGER_JOURNALMODE_PERSIST
+ || eMode==PAGER_JOURNALMODE_OFF
+ || eMode==PAGER_JOURNALMODE_WAL
+ || eMode==PAGER_JOURNALMODE_MEMORY );
+
+ /* This routine is only called from the OP_JournalMode opcode, and
+ ** the logic there will never allow a temporary file to be changed
+ ** to WAL mode.
+ */
+ assert( pPager->tempFile==0 || eMode!=PAGER_JOURNALMODE_WAL );
+
+ /* Do allow the journalmode of an in-memory database to be set to
+ ** anything other than MEMORY or OFF
+ */
+ if( MEMDB ){
+ assert( eOld==PAGER_JOURNALMODE_MEMORY || eOld==PAGER_JOURNALMODE_OFF );
+ if( eMode!=PAGER_JOURNALMODE_MEMORY && eMode!=PAGER_JOURNALMODE_OFF ){
+ eMode = eOld;
+ }
+ }
+
+ if( eMode!=eOld ){
+
+ /* Change the journal mode. */
+ assert( pPager->eState!=PAGER_ERROR );
+ pPager->journalMode = (u8)eMode;
+
+ /* When transistioning from TRUNCATE or PERSIST to any other journal
+ ** mode except WAL, unless the pager is in locking_mode=exclusive mode,
+ ** delete the journal file.
+ */
+ assert( (PAGER_JOURNALMODE_TRUNCATE & 5)==1 );
+ assert( (PAGER_JOURNALMODE_PERSIST & 5)==1 );
+ assert( (PAGER_JOURNALMODE_DELETE & 5)==0 );
+ assert( (PAGER_JOURNALMODE_MEMORY & 5)==4 );
+ assert( (PAGER_JOURNALMODE_OFF & 5)==0 );
+ assert( (PAGER_JOURNALMODE_WAL & 5)==5 );
+
+ assert( isOpen(pPager->fd) || pPager->exclusiveMode );
+ if( !pPager->exclusiveMode && (eOld & 5)==1 && (eMode & 1)==0 ){
+
+ /* In this case we would like to delete the journal file. If it is
+ ** not possible, then that is not a problem. Deleting the journal file
+ ** here is an optimization only.
+ **
+ ** Before deleting the journal file, obtain a RESERVED lock on the
+ ** database file. This ensures that the journal file is not deleted
+ ** while it is in use by some other client.
+ */
+ sqlite3OsClose(pPager->jfd);
+ if( pPager->eLock>=RESERVED_LOCK ){
+ sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+ }else{
+ int rc = SQLITE_OK;
+ int state = pPager->eState;
+ assert( state==PAGER_OPEN || state==PAGER_READER );
+ if( state==PAGER_OPEN ){
+ rc = sqlite3PagerSharedLock(pPager);
+ }
+ if( pPager->eState==PAGER_READER ){
+ assert( rc==SQLITE_OK );
+ rc = pagerLockDb(pPager, RESERVED_LOCK);
+ }
+ if( rc==SQLITE_OK ){
+ sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+ }
+ if( rc==SQLITE_OK && state==PAGER_READER ){
+ pagerUnlockDb(pPager, SHARED_LOCK);
+ }else if( state==PAGER_OPEN ){
+ pager_unlock(pPager);
+ }
+ assert( state==pPager->eState );
+ }
+ }
+ }
+
+ /* Return the new journal mode */
+ return (int)pPager->journalMode;
+}
+
+/*
+** Return the current journal mode.
+*/
+SQLITE_PRIVATE int sqlite3PagerGetJournalMode(Pager *pPager){
+ return (int)pPager->journalMode;
+}
+
+/*
+** Return TRUE if the pager is in a state where it is OK to change the
+** journalmode. Journalmode changes can only happen when the database
+** is unmodified.
+*/
+SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager *pPager){
+ assert( assert_pager_state(pPager) );
+ if( pPager->eState>=PAGER_WRITER_CACHEMOD ) return 0;
+ if( NEVER(isOpen(pPager->jfd) && pPager->journalOff>0) ) return 0;
+ return 1;
+}
+
+/*
+** Get/set the size-limit used for persistent journal files.
+**
+** Setting the size limit to -1 means no limit is enforced.
+** An attempt to set a limit smaller than -1 is a no-op.
+*/
+SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *pPager, i64 iLimit){
+ if( iLimit>=-1 ){
+ pPager->journalSizeLimit = iLimit;
+ sqlite3WalLimit(pPager->pWal, iLimit);
+ }
+ return pPager->journalSizeLimit;
+}
+
+/*
+** Return a pointer to the pPager->pBackup variable. The backup module
+** in backup.c maintains the content of this variable. This module
+** uses it opaquely as an argument to sqlite3BackupRestart() and
+** sqlite3BackupUpdate() only.
+*/
+SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager *pPager){
+ return &pPager->pBackup;
+}
+
+#ifndef SQLITE_OMIT_VACUUM
+/*
+** Unless this is an in-memory or temporary database, clear the pager cache.
+*/
+SQLITE_PRIVATE void sqlite3PagerClearCache(Pager *pPager){
+ if( !MEMDB && pPager->tempFile==0 ) pager_reset(pPager);
+}
+#endif
+
+#ifndef SQLITE_OMIT_WAL
+/*
+** This function is called when the user invokes "PRAGMA wal_checkpoint",
+** "PRAGMA wal_blocking_checkpoint" or calls the sqlite3_wal_checkpoint()
+** or wal_blocking_checkpoint() API functions.
+**
+** Parameter eMode is one of SQLITE_CHECKPOINT_PASSIVE, FULL or RESTART.
+*/
+SQLITE_PRIVATE int sqlite3PagerCheckpoint(Pager *pPager, int eMode, int *pnLog, int *pnCkpt){
+ int rc = SQLITE_OK;
+ if( pPager->pWal ){
+ rc = sqlite3WalCheckpoint(pPager->pWal, eMode,
+ pPager->xBusyHandler, pPager->pBusyHandlerArg,
+ pPager->ckptSyncFlags, pPager->pageSize, (u8 *)pPager->pTmpSpace,
+ pnLog, pnCkpt
+ );
+ }
+ return rc;
+}
+
+SQLITE_PRIVATE int sqlite3PagerWalCallback(Pager *pPager){
+ return sqlite3WalCallback(pPager->pWal);
+}
+
+/*
+** Return true if the underlying VFS for the given pager supports the
+** primitives necessary for write-ahead logging.
+*/
+SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager){
+ const sqlite3_io_methods *pMethods = pPager->fd->pMethods;
+ return pPager->exclusiveMode || (pMethods->iVersion>=2 && pMethods->xShmMap);
+}
+
+/*
+** Attempt to take an exclusive lock on the database file. If a PENDING lock
+** is obtained instead, immediately release it.
+*/
+static int pagerExclusiveLock(Pager *pPager){
+ int rc; /* Return code */
+
+ assert( pPager->eLock==SHARED_LOCK || pPager->eLock==EXCLUSIVE_LOCK );
+ rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
+ if( rc!=SQLITE_OK ){
+ /* If the attempt to grab the exclusive lock failed, release the
+ ** pending lock that may have been obtained instead. */
+ pagerUnlockDb(pPager, SHARED_LOCK);
+ }
+
+ return rc;
+}
+
+/*
+** Call sqlite3WalOpen() to open the WAL handle. If the pager is in
+** exclusive-locking mode when this function is called, take an EXCLUSIVE
+** lock on the database file and use heap-memory to store the wal-index
+** in. Otherwise, use the normal shared-memory.
+*/
+static int pagerOpenWal(Pager *pPager){
+ int rc = SQLITE_OK;
+
+ assert( pPager->pWal==0 && pPager->tempFile==0 );
+ assert( pPager->eLock==SHARED_LOCK || pPager->eLock==EXCLUSIVE_LOCK );
+
+ /* If the pager is already in exclusive-mode, the WAL module will use
+ ** heap-memory for the wal-index instead of the VFS shared-memory
+ ** implementation. Take the exclusive lock now, before opening the WAL
+ ** file, to make sure this is safe.
+ */
+ if( pPager->exclusiveMode ){
+ rc = pagerExclusiveLock(pPager);
+ }
+
+ /* Open the connection to the log file. If this operation fails,
+ ** (e.g. due to malloc() failure), return an error code.
+ */
+ if( rc==SQLITE_OK ){
+ rc = sqlite3WalOpen(pPager->pVfs,
+ pPager->fd, pPager->zWal, pPager->exclusiveMode,
+ pPager->journalSizeLimit, &pPager->pWal
+ );
+ }
+ pagerFixMaplimit(pPager);
+
+ return rc;
+}
+
+
+/*
+** The caller must be holding a SHARED lock on the database file to call
+** this function.
+**
+** If the pager passed as the first argument is open on a real database
+** file (not a temp file or an in-memory database), and the WAL file
+** is not already open, make an attempt to open it now. If successful,
+** return SQLITE_OK. If an error occurs or the VFS used by the pager does
+** not support the xShmXXX() methods, return an error code. *pbOpen is
+** not modified in either case.
+**
+** If the pager is open on a temp-file (or in-memory database), or if
+** the WAL file is already open, set *pbOpen to 1 and return SQLITE_OK
+** without doing anything.
+*/
+SQLITE_PRIVATE int sqlite3PagerOpenWal(
+ Pager *pPager, /* Pager object */
+ int *pbOpen /* OUT: Set to true if call is a no-op */
+){
+ int rc = SQLITE_OK; /* Return code */
+
+ assert( assert_pager_state(pPager) );
+ assert( pPager->eState==PAGER_OPEN || pbOpen );
+ assert( pPager->eState==PAGER_READER || !pbOpen );
+ assert( pbOpen==0 || *pbOpen==0 );
+ assert( pbOpen!=0 || (!pPager->tempFile && !pPager->pWal) );
+
+ if( !pPager->tempFile && !pPager->pWal ){
+ if( !sqlite3PagerWalSupported(pPager) ) return SQLITE_CANTOPEN;
+
+ /* Close any rollback journal previously open */
+ sqlite3OsClose(pPager->jfd);
+
+ rc = pagerOpenWal(pPager);
+ if( rc==SQLITE_OK ){
+ pPager->journalMode = PAGER_JOURNALMODE_WAL;
+ pPager->eState = PAGER_OPEN;
+ }
+ }else{
+ *pbOpen = 1;
+ }
+
+ return rc;
+}
+
+/*
+** This function is called to close the connection to the log file prior
+** to switching from WAL to rollback mode.
+**
+** Before closing the log file, this function attempts to take an
+** EXCLUSIVE lock on the database file. If this cannot be obtained, an
+** error (SQLITE_BUSY) is returned and the log connection is not closed.
+** If successful, the EXCLUSIVE lock is not released before returning.
+*/
+SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager){
+ int rc = SQLITE_OK;
+
+ assert( pPager->journalMode==PAGER_JOURNALMODE_WAL );
+
+ /* If the log file is not already open, but does exist in the file-system,
+ ** it may need to be checkpointed before the connection can switch to
+ ** rollback mode. Open it now so this can happen.
+ */
+ if( !pPager->pWal ){
+ int logexists = 0;
+ rc = pagerLockDb(pPager, SHARED_LOCK);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3OsAccess(
+ pPager->pVfs, pPager->zWal, SQLITE_ACCESS_EXISTS, &logexists
+ );
+ }
+ if( rc==SQLITE_OK && logexists ){
+ rc = pagerOpenWal(pPager);
+ }
+ }
+
+ /* Checkpoint and close the log. Because an EXCLUSIVE lock is held on
+ ** the database file, the log and log-summary files will be deleted.
+ */
+ if( rc==SQLITE_OK && pPager->pWal ){
+ rc = pagerExclusiveLock(pPager);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3WalClose(pPager->pWal, pPager->ckptSyncFlags,
+ pPager->pageSize, (u8*)pPager->pTmpSpace);
+ pPager->pWal = 0;
+ pagerFixMaplimit(pPager);
+ }
+ }
+ return rc;
+}
+
+#endif /* !SQLITE_OMIT_WAL */
+
+#ifdef SQLITE_ENABLE_ZIPVFS
+/*
+** A read-lock must be held on the pager when this function is called. If
+** the pager is in WAL mode and the WAL file currently contains one or more
+** frames, return the size in bytes of the page images stored within the
+** WAL frames. Otherwise, if this is not a WAL database or the WAL file
+** is empty, return 0.
+*/
+SQLITE_PRIVATE int sqlite3PagerWalFramesize(Pager *pPager){
+ assert( pPager->eState==PAGER_READER );
+ return sqlite3WalFramesize(pPager->pWal);
+}
+#endif
+
+#endif /* SQLITE_OMIT_DISKIO */
+
+/************** End of pager.c ***********************************************/
+/************** Begin file wal.c *********************************************/
+/*
+** 2010 February 1
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file contains the implementation of a write-ahead log (WAL) used in
+** "journal_mode=WAL" mode.
+**
+** WRITE-AHEAD LOG (WAL) FILE FORMAT
+**
+** A WAL file consists of a header followed by zero or more "frames".
+** Each frame records the revised content of a single page from the
+** database file. All changes to the database are recorded by writing
+** frames into the WAL. Transactions commit when a frame is written that
+** contains a commit marker. A single WAL can and usually does record
+** multiple transactions. Periodically, the content of the WAL is
+** transferred back into the database file in an operation called a
+** "checkpoint".
+**
+** A single WAL file can be used multiple times. In other words, the
+** WAL can fill up with frames and then be checkpointed and then new
+** frames can overwrite the old ones. A WAL always grows from beginning
+** toward the end. Checksums and counters attached to each frame are
+** used to determine which frames within the WAL are valid and which
+** are leftovers from prior checkpoints.
+**
+** The WAL header is 32 bytes in size and consists of the following eight
+** big-endian 32-bit unsigned integer values:
+**
+** 0: Magic number. 0x377f0682 or 0x377f0683
+** 4: File format version. Currently 3007000
+** 8: Database page size. Example: 1024
+** 12: Checkpoint sequence number
+** 16: Salt-1, random integer incremented with each checkpoint
+** 20: Salt-2, a different random integer changing with each ckpt
+** 24: Checksum-1 (first part of checksum for first 24 bytes of header).
+** 28: Checksum-2 (second part of checksum for first 24 bytes of header).
+**
+** Immediately following the wal-header are zero or more frames. Each
+** frame consists of a 24-byte frame-header followed by a bytes
+** of page data. The frame-header is six big-endian 32-bit unsigned
+** integer values, as follows:
+**
+** 0: Page number.
+** 4: For commit records, the size of the database image in pages
+** after the commit. For all other records, zero.
+** 8: Salt-1 (copied from the header)
+** 12: Salt-2 (copied from the header)
+** 16: Checksum-1.
+** 20: Checksum-2.
+**
+** A frame is considered valid if and only if the following conditions are
+** true:
+**
+** (1) The salt-1 and salt-2 values in the frame-header match
+** salt values in the wal-header
+**
+** (2) The checksum values in the final 8 bytes of the frame-header
+** exactly match the checksum computed consecutively on the
+** WAL header and the first 8 bytes and the content of all frames
+** up to and including the current frame.
+**
+** The checksum is computed using 32-bit big-endian integers if the
+** magic number in the first 4 bytes of the WAL is 0x377f0683 and it
+** is computed using little-endian if the magic number is 0x377f0682.
+** The checksum values are always stored in the frame header in a
+** big-endian format regardless of which byte order is used to compute
+** the checksum. The checksum is computed by interpreting the input as
+** an even number of unsigned 32-bit integers: x[0] through x[N]. The
+** algorithm used for the checksum is as follows:
+**
+** for i from 0 to n-1 step 2:
+** s0 += x[i] + s1;
+** s1 += x[i+1] + s0;
+** endfor
+**
+** Note that s0 and s1 are both weighted checksums using fibonacci weights
+** in reverse order (the largest fibonacci weight occurs on the first element
+** of the sequence being summed.) The s1 value spans all 32-bit
+** terms of the sequence whereas s0 omits the final term.
+**
+** On a checkpoint, the WAL is first VFS.xSync-ed, then valid content of the
+** WAL is transferred into the database, then the database is VFS.xSync-ed.
+** The VFS.xSync operations serve as write barriers - all writes launched
+** before the xSync must complete before any write that launches after the
+** xSync begins.
+**
+** After each checkpoint, the salt-1 value is incremented and the salt-2
+** value is randomized. This prevents old and new frames in the WAL from
+** being considered valid at the same time and being checkpointing together
+** following a crash.
+**
+** READER ALGORITHM
+**
+** To read a page from the database (call it page number P), a reader
+** first checks the WAL to see if it contains page P. If so, then the
+** last valid instance of page P that is a followed by a commit frame
+** or is a commit frame itself becomes the value read. If the WAL
+** contains no copies of page P that are valid and which are a commit
+** frame or are followed by a commit frame, then page P is read from
+** the database file.
+**
+** To start a read transaction, the reader records the index of the last
+** valid frame in the WAL. The reader uses this recorded "mxFrame" value
+** for all subsequent read operations. New transactions can be appended
+** to the WAL, but as long as the reader uses its original mxFrame value
+** and ignores the newly appended content, it will see a consistent snapshot
+** of the database from a single point in time. This technique allows
+** multiple concurrent readers to view different versions of the database
+** content simultaneously.
+**
+** The reader algorithm in the previous paragraphs works correctly, but
+** because frames for page P can appear anywhere within the WAL, the
+** reader has to scan the entire WAL looking for page P frames. If the
+** WAL is large (multiple megabytes is typical) that scan can be slow,
+** and read performance suffers. To overcome this problem, a separate
+** data structure called the wal-index is maintained to expedite the
+** search for frames of a particular page.
+**
+** WAL-INDEX FORMAT
+**
+** Conceptually, the wal-index is shared memory, though VFS implementations
+** might choose to implement the wal-index using a mmapped file. Because
+** the wal-index is shared memory, SQLite does not support journal_mode=WAL
+** on a network filesystem. All users of the database must be able to
+** share memory.
+**
+** The wal-index is transient. After a crash, the wal-index can (and should
+** be) reconstructed from the original WAL file. In fact, the VFS is required
+** to either truncate or zero the header of the wal-index when the last
+** connection to it closes. Because the wal-index is transient, it can
+** use an architecture-specific format; it does not have to be cross-platform.
+** Hence, unlike the database and WAL file formats which store all values
+** as big endian, the wal-index can store multi-byte values in the native
+** byte order of the host computer.
+**
+** The purpose of the wal-index is to answer this question quickly: Given
+** a page number P and a maximum frame index M, return the index of the
+** last frame in the wal before frame M for page P in the WAL, or return
+** NULL if there are no frames for page P in the WAL prior to M.
+**
+** The wal-index consists of a header region, followed by an one or
+** more index blocks.
+**
+** The wal-index header contains the total number of frames within the WAL
+** in the mxFrame field.
+**
+** Each index block except for the first contains information on
+** HASHTABLE_NPAGE frames. The first index block contains information on
+** HASHTABLE_NPAGE_ONE frames. The values of HASHTABLE_NPAGE_ONE and
+** HASHTABLE_NPAGE are selected so that together the wal-index header and
+** first index block are the same size as all other index blocks in the
+** wal-index.
+**
+** Each index block contains two sections, a page-mapping that contains the
+** database page number associated with each wal frame, and a hash-table
+** that allows readers to query an index block for a specific page number.
+** The page-mapping is an array of HASHTABLE_NPAGE (or HASHTABLE_NPAGE_ONE
+** for the first index block) 32-bit page numbers. The first entry in the
+** first index-block contains the database page number corresponding to the
+** first frame in the WAL file. The first entry in the second index block
+** in the WAL file corresponds to the (HASHTABLE_NPAGE_ONE+1)th frame in
+** the log, and so on.
+**
+** The last index block in a wal-index usually contains less than the full
+** complement of HASHTABLE_NPAGE (or HASHTABLE_NPAGE_ONE) page-numbers,
+** depending on the contents of the WAL file. This does not change the
+** allocated size of the page-mapping array - the page-mapping array merely
+** contains unused entries.
+**
+** Even without using the hash table, the last frame for page P
+** can be found by scanning the page-mapping sections of each index block
+** starting with the last index block and moving toward the first, and
+** within each index block, starting at the end and moving toward the
+** beginning. The first entry that equals P corresponds to the frame
+** holding the content for that page.
+**
+** The hash table consists of HASHTABLE_NSLOT 16-bit unsigned integers.
+** HASHTABLE_NSLOT = 2*HASHTABLE_NPAGE, and there is one entry in the
+** hash table for each page number in the mapping section, so the hash
+** table is never more than half full. The expected number of collisions
+** prior to finding a match is 1. Each entry of the hash table is an
+** 1-based index of an entry in the mapping section of the same
+** index block. Let K be the 1-based index of the largest entry in
+** the mapping section. (For index blocks other than the last, K will
+** always be exactly HASHTABLE_NPAGE (4096) and for the last index block
+** K will be (mxFrame%HASHTABLE_NPAGE).) Unused slots of the hash table
+** contain a value of 0.
+**
+** To look for page P in the hash table, first compute a hash iKey on
+** P as follows:
+**
+** iKey = (P * 383) % HASHTABLE_NSLOT
+**
+** Then start scanning entries of the hash table, starting with iKey
+** (wrapping around to the beginning when the end of the hash table is
+** reached) until an unused hash slot is found. Let the first unused slot
+** be at index iUnused. (iUnused might be less than iKey if there was
+** wrap-around.) Because the hash table is never more than half full,
+** the search is guaranteed to eventually hit an unused entry. Let
+** iMax be the value between iKey and iUnused, closest to iUnused,
+** where aHash[iMax]==P. If there is no iMax entry (if there exists
+** no hash slot such that aHash[i]==p) then page P is not in the
+** current index block. Otherwise the iMax-th mapping entry of the
+** current index block corresponds to the last entry that references
+** page P.
+**
+** A hash search begins with the last index block and moves toward the
+** first index block, looking for entries corresponding to page P. On
+** average, only two or three slots in each index block need to be
+** examined in order to either find the last entry for page P, or to
+** establish that no such entry exists in the block. Each index block
+** holds over 4000 entries. So two or three index blocks are sufficient
+** to cover a typical 10 megabyte WAL file, assuming 1K pages. 8 or 10
+** comparisons (on average) suffice to either locate a frame in the
+** WAL or to establish that the frame does not exist in the WAL. This
+** is much faster than scanning the entire 10MB WAL.
+**
+** Note that entries are added in order of increasing K. Hence, one
+** reader might be using some value K0 and a second reader that started
+** at a later time (after additional transactions were added to the WAL
+** and to the wal-index) might be using a different value K1, where K1>K0.
+** Both readers can use the same hash table and mapping section to get
+** the correct result. There may be entries in the hash table with
+** K>K0 but to the first reader, those entries will appear to be unused
+** slots in the hash table and so the first reader will get an answer as
+** if no values greater than K0 had ever been inserted into the hash table
+** in the first place - which is what reader one wants. Meanwhile, the
+** second reader using K1 will see additional values that were inserted
+** later, which is exactly what reader two wants.
+**
+** When a rollback occurs, the value of K is decreased. Hash table entries
+** that correspond to frames greater than the new K value are removed
+** from the hash table at this point.
+*/
+#ifndef SQLITE_OMIT_WAL
+
+
+/*
+** Trace output macros
+*/
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+SQLITE_PRIVATE int sqlite3WalTrace = 0;
+# define WALTRACE(X) if(sqlite3WalTrace) sqlite3DebugPrintf X
+#else
+# define WALTRACE(X)
+#endif
+
+/*
+** The maximum (and only) versions of the wal and wal-index formats
+** that may be interpreted by this version of SQLite.
+**
+** If a client begins recovering a WAL file and finds that (a) the checksum
+** values in the wal-header are correct and (b) the version field is not
+** WAL_MAX_VERSION, recovery fails and SQLite returns SQLITE_CANTOPEN.
+**
+** Similarly, if a client successfully reads a wal-index header (i.e. the
+** checksum test is successful) and finds that the version field is not
+** WALINDEX_MAX_VERSION, then no read-transaction is opened and SQLite
+** returns SQLITE_CANTOPEN.
+*/
+#define WAL_MAX_VERSION 3007000
+#define WALINDEX_MAX_VERSION 3007000
+
+/*
+** Indices of various locking bytes. WAL_NREADER is the number
+** of available reader locks and should be at least 3.
+*/
+#define WAL_WRITE_LOCK 0
+#define WAL_ALL_BUT_WRITE 1
+#define WAL_CKPT_LOCK 1
+#define WAL_RECOVER_LOCK 2
+#define WAL_READ_LOCK(I) (3+(I))
+#define WAL_NREADER (SQLITE_SHM_NLOCK-3)
+
+
+/* Object declarations */
+typedef struct WalIndexHdr WalIndexHdr;
+typedef struct WalIterator WalIterator;
+typedef struct WalCkptInfo WalCkptInfo;
+
+
+/*
+** The following object holds a copy of the wal-index header content.
+**
+** The actual header in the wal-index consists of two copies of this
+** object.
+**
+** The szPage value can be any power of 2 between 512 and 32768, inclusive.
+** Or it can be 1 to represent a 65536-byte page. The latter case was
+** added in 3.7.1 when support for 64K pages was added.
+*/
+struct WalIndexHdr {
+ u32 iVersion; /* Wal-index version */
+ u32 unused; /* Unused (padding) field */
+ u32 iChange; /* Counter incremented each transaction */
+ u8 isInit; /* 1 when initialized */
+ u8 bigEndCksum; /* True if checksums in WAL are big-endian */
+ u16 szPage; /* Database page size in bytes. 1==64K */
+ u32 mxFrame; /* Index of last valid frame in the WAL */
+ u32 nPage; /* Size of database in pages */
+ u32 aFrameCksum[2]; /* Checksum of last frame in log */
+ u32 aSalt[2]; /* Two salt values copied from WAL header */
+ u32 aCksum[2]; /* Checksum over all prior fields */
+};
+
+/*
+** A copy of the following object occurs in the wal-index immediately
+** following the second copy of the WalIndexHdr. This object stores
+** information used by checkpoint.
+**
+** nBackfill is the number of frames in the WAL that have been written
+** back into the database. (We call the act of moving content from WAL to
+** database "backfilling".) The nBackfill number is never greater than
+** WalIndexHdr.mxFrame. nBackfill can only be increased by threads
+** holding the WAL_CKPT_LOCK lock (which includes a recovery thread).
+** However, a WAL_WRITE_LOCK thread can move the value of nBackfill from
+** mxFrame back to zero when the WAL is reset.
+**
+** There is one entry in aReadMark[] for each reader lock. If a reader
+** holds read-lock K, then the value in aReadMark[K] is no greater than
+** the mxFrame for that reader. The value READMARK_NOT_USED (0xffffffff)
+** for any aReadMark[] means that entry is unused. aReadMark[0] is
+** a special case; its value is never used and it exists as a place-holder
+** to avoid having to offset aReadMark[] indexs by one. Readers holding
+** WAL_READ_LOCK(0) always ignore the entire WAL and read all content
+** directly from the database.
+**
+** The value of aReadMark[K] may only be changed by a thread that
+** is holding an exclusive lock on WAL_READ_LOCK(K). Thus, the value of
+** aReadMark[K] cannot changed while there is a reader is using that mark
+** since the reader will be holding a shared lock on WAL_READ_LOCK(K).
+**
+** The checkpointer may only transfer frames from WAL to database where
+** the frame numbers are less than or equal to every aReadMark[] that is
+** in use (that is, every aReadMark[j] for which there is a corresponding
+** WAL_READ_LOCK(j)). New readers (usually) pick the aReadMark[] with the
+** largest value and will increase an unused aReadMark[] to mxFrame if there
+** is not already an aReadMark[] equal to mxFrame. The exception to the
+** previous sentence is when nBackfill equals mxFrame (meaning that everything
+** in the WAL has been backfilled into the database) then new readers
+** will choose aReadMark[0] which has value 0 and hence such reader will
+** get all their all content directly from the database file and ignore
+** the WAL.
+**
+** Writers normally append new frames to the end of the WAL. However,
+** if nBackfill equals mxFrame (meaning that all WAL content has been
+** written back into the database) and if no readers are using the WAL
+** (in other words, if there are no WAL_READ_LOCK(i) where i>0) then
+** the writer will first "reset" the WAL back to the beginning and start
+** writing new content beginning at frame 1.
+**
+** We assume that 32-bit loads are atomic and so no locks are needed in
+** order to read from any aReadMark[] entries.
+*/
+struct WalCkptInfo {
+ u32 nBackfill; /* Number of WAL frames backfilled into DB */
+ u32 aReadMark[WAL_NREADER]; /* Reader marks */
+};
+#define READMARK_NOT_USED 0xffffffff
+
+
+/* A block of WALINDEX_LOCK_RESERVED bytes beginning at
+** WALINDEX_LOCK_OFFSET is reserved for locks. Since some systems
+** only support mandatory file-locks, we do not read or write data
+** from the region of the file on which locks are applied.
+*/
+#define WALINDEX_LOCK_OFFSET (sizeof(WalIndexHdr)*2 + sizeof(WalCkptInfo))
+#define WALINDEX_LOCK_RESERVED 16
+#define WALINDEX_HDR_SIZE (WALINDEX_LOCK_OFFSET+WALINDEX_LOCK_RESERVED)
+
+/* Size of header before each frame in wal */
+#define WAL_FRAME_HDRSIZE 24
+
+/* Size of write ahead log header, including checksum. */
+/* #define WAL_HDRSIZE 24 */
+#define WAL_HDRSIZE 32
+
+/* WAL magic value. Either this value, or the same value with the least
+** significant bit also set (WAL_MAGIC | 0x00000001) is stored in 32-bit
+** big-endian format in the first 4 bytes of a WAL file.
+**
+** If the LSB is set, then the checksums for each frame within the WAL
+** file are calculated by treating all data as an array of 32-bit
+** big-endian words. Otherwise, they are calculated by interpreting
+** all data as 32-bit little-endian words.
+*/
+#define WAL_MAGIC 0x377f0682
+
+/*
+** Return the offset of frame iFrame in the write-ahead log file,
+** assuming a database page size of szPage bytes. The offset returned
+** is to the start of the write-ahead log frame-header.
+*/
+#define walFrameOffset(iFrame, szPage) ( \
+ WAL_HDRSIZE + ((iFrame)-1)*(i64)((szPage)+WAL_FRAME_HDRSIZE) \
+)
+
+/*
+** An open write-ahead log file is represented by an instance of the
+** following object.
+*/
+struct Wal {
+ sqlite3_vfs *pVfs; /* The VFS used to create pDbFd */
+ sqlite3_file *pDbFd; /* File handle for the database file */
+ sqlite3_file *pWalFd; /* File handle for WAL file */
+ u32 iCallback; /* Value to pass to log callback (or 0) */
+ i64 mxWalSize; /* Truncate WAL to this size upon reset */
+ int nWiData; /* Size of array apWiData */
+ int szFirstBlock; /* Size of first block written to WAL file */
+ volatile u32 **apWiData; /* Pointer to wal-index content in memory */
+ u32 szPage; /* Database page size */
+ i16 readLock; /* Which read lock is being held. -1 for none */
+ u8 syncFlags; /* Flags to use to sync header writes */
+ u8 exclusiveMode; /* Non-zero if connection is in exclusive mode */
+ u8 writeLock; /* True if in a write transaction */
+ u8 ckptLock; /* True if holding a checkpoint lock */
+ u8 readOnly; /* WAL_RDWR, WAL_RDONLY, or WAL_SHM_RDONLY */
+ u8 truncateOnCommit; /* True to truncate WAL file on commit */
+ u8 syncHeader; /* Fsync the WAL header if true */
+ u8 padToSectorBoundary; /* Pad transactions out to the next sector */
+ WalIndexHdr hdr; /* Wal-index header for current transaction */
+ const char *zWalName; /* Name of WAL file */
+ u32 nCkpt; /* Checkpoint sequence counter in the wal-header */
+#ifdef SQLITE_DEBUG
+ u8 lockError; /* True if a locking error has occurred */
+#endif
+};
+
+/*
+** Candidate values for Wal.exclusiveMode.
+*/
+#define WAL_NORMAL_MODE 0
+#define WAL_EXCLUSIVE_MODE 1
+#define WAL_HEAPMEMORY_MODE 2
+
+/*
+** Possible values for WAL.readOnly
+*/
+#define WAL_RDWR 0 /* Normal read/write connection */
+#define WAL_RDONLY 1 /* The WAL file is readonly */
+#define WAL_SHM_RDONLY 2 /* The SHM file is readonly */
+
+/*
+** Each page of the wal-index mapping contains a hash-table made up of
+** an array of HASHTABLE_NSLOT elements of the following type.
+*/
+typedef u16 ht_slot;
+
+/*
+** This structure is used to implement an iterator that loops through
+** all frames in the WAL in database page order. Where two or more frames
+** correspond to the same database page, the iterator visits only the
+** frame most recently written to the WAL (in other words, the frame with
+** the largest index).
+**
+** The internals of this structure are only accessed by:
+**
+** walIteratorInit() - Create a new iterator,
+** walIteratorNext() - Step an iterator,
+** walIteratorFree() - Free an iterator.
+**
+** This functionality is used by the checkpoint code (see walCheckpoint()).
+*/
+struct WalIterator {
+ int iPrior; /* Last result returned from the iterator */
+ int nSegment; /* Number of entries in aSegment[] */
+ struct WalSegment {
+ int iNext; /* Next slot in aIndex[] not yet returned */
+ ht_slot *aIndex; /* i0, i1, i2... such that aPgno[iN] ascend */
+ u32 *aPgno; /* Array of page numbers. */
+ int nEntry; /* Nr. of entries in aPgno[] and aIndex[] */
+ int iZero; /* Frame number associated with aPgno[0] */
+ } aSegment[1]; /* One for every 32KB page in the wal-index */
+};
+
+/*
+** Define the parameters of the hash tables in the wal-index file. There
+** is a hash-table following every HASHTABLE_NPAGE page numbers in the
+** wal-index.
+**
+** Changing any of these constants will alter the wal-index format and
+** create incompatibilities.
+*/
+#define HASHTABLE_NPAGE 4096 /* Must be power of 2 */
+#define HASHTABLE_HASH_1 383 /* Should be prime */
+#define HASHTABLE_NSLOT (HASHTABLE_NPAGE*2) /* Must be a power of 2 */
+
+/*
+** The block of page numbers associated with the first hash-table in a
+** wal-index is smaller than usual. This is so that there is a complete
+** hash-table on each aligned 32KB page of the wal-index.
+*/
+#define HASHTABLE_NPAGE_ONE (HASHTABLE_NPAGE - (WALINDEX_HDR_SIZE/sizeof(u32)))
+
+/* The wal-index is divided into pages of WALINDEX_PGSZ bytes each. */
+#define WALINDEX_PGSZ ( \
+ sizeof(ht_slot)*HASHTABLE_NSLOT + HASHTABLE_NPAGE*sizeof(u32) \
+)
+
+/*
+** Obtain a pointer to the iPage'th page of the wal-index. The wal-index
+** is broken into pages of WALINDEX_PGSZ bytes. Wal-index pages are
+** numbered from zero.
+**
+** If this call is successful, *ppPage is set to point to the wal-index
+** page and SQLITE_OK is returned. If an error (an OOM or VFS error) occurs,
+** then an SQLite error code is returned and *ppPage is set to 0.
+*/
+static int walIndexPage(Wal *pWal, int iPage, volatile u32 **ppPage){
+ int rc = SQLITE_OK;
+
+ /* Enlarge the pWal->apWiData[] array if required */
+ if( pWal->nWiData<=iPage ){
+ int nByte = sizeof(u32*)*(iPage+1);
+ volatile u32 **apNew;
+ apNew = (volatile u32 **)sqlite3_realloc((void *)pWal->apWiData, nByte);
+ if( !apNew ){
+ *ppPage = 0;
+ return SQLITE_NOMEM;
+ }
+ memset((void*)&apNew[pWal->nWiData], 0,
+ sizeof(u32*)*(iPage+1-pWal->nWiData));
+ pWal->apWiData = apNew;
+ pWal->nWiData = iPage+1;
+ }
+
+ /* Request a pointer to the required page from the VFS */
+ if( pWal->apWiData[iPage]==0 ){
+ if( pWal->exclusiveMode==WAL_HEAPMEMORY_MODE ){
+ pWal->apWiData[iPage] = (u32 volatile *)sqlite3MallocZero(WALINDEX_PGSZ);
+ if( !pWal->apWiData[iPage] ) rc = SQLITE_NOMEM;
+ }else{
+ rc = sqlite3OsShmMap(pWal->pDbFd, iPage, WALINDEX_PGSZ,
+ pWal->writeLock, (void volatile **)&pWal->apWiData[iPage]
+ );
+ if( rc==SQLITE_READONLY ){
+ pWal->readOnly |= WAL_SHM_RDONLY;
+ rc = SQLITE_OK;
+ }
+ }
+ }
+
+ *ppPage = pWal->apWiData[iPage];
+ assert( iPage==0 || *ppPage || rc!=SQLITE_OK );
+ return rc;
+}
+
+/*
+** Return a pointer to the WalCkptInfo structure in the wal-index.
+*/
+static volatile WalCkptInfo *walCkptInfo(Wal *pWal){
+ assert( pWal->nWiData>0 && pWal->apWiData[0] );
+ return (volatile WalCkptInfo*)&(pWal->apWiData[0][sizeof(WalIndexHdr)/2]);
+}
+
+/*
+** Return a pointer to the WalIndexHdr structure in the wal-index.
+*/
+static volatile WalIndexHdr *walIndexHdr(Wal *pWal){
+ assert( pWal->nWiData>0 && pWal->apWiData[0] );
+ return (volatile WalIndexHdr*)pWal->apWiData[0];
+}
+
+/*
+** The argument to this macro must be of type u32. On a little-endian
+** architecture, it returns the u32 value that results from interpreting
+** the 4 bytes as a big-endian value. On a big-endian architecture, it
+** returns the value that would be produced by intepreting the 4 bytes
+** of the input value as a little-endian integer.
+*/
+#define BYTESWAP32(x) ( \
+ (((x)&0x000000FF)<<24) + (((x)&0x0000FF00)<<8) \
+ + (((x)&0x00FF0000)>>8) + (((x)&0xFF000000)>>24) \
+)
+
+/*
+** Generate or extend an 8 byte checksum based on the data in
+** array aByte[] and the initial values of aIn[0] and aIn[1] (or
+** initial values of 0 and 0 if aIn==NULL).
+**
+** The checksum is written back into aOut[] before returning.
+**
+** nByte must be a positive multiple of 8.
+*/
+static void walChecksumBytes(
+ int nativeCksum, /* True for native byte-order, false for non-native */
+ u8 *a, /* Content to be checksummed */
+ int nByte, /* Bytes of content in a[]. Must be a multiple of 8. */
+ const u32 *aIn, /* Initial checksum value input */
+ u32 *aOut /* OUT: Final checksum value output */
+){
+ u32 s1, s2;
+ u32 *aData = (u32 *)a;
+ u32 *aEnd = (u32 *)&a[nByte];
+
+ if( aIn ){
+ s1 = aIn[0];
+ s2 = aIn[1];
+ }else{
+ s1 = s2 = 0;
+ }
+
+ assert( nByte>=8 );
+ assert( (nByte&0x00000007)==0 );
+
+ if( nativeCksum ){
+ do {
+ s1 += *aData++ + s2;
+ s2 += *aData++ + s1;
+ }while( aDataexclusiveMode!=WAL_HEAPMEMORY_MODE ){
+ sqlite3OsShmBarrier(pWal->pDbFd);
+ }
+}
+
+/*
+** Write the header information in pWal->hdr into the wal-index.
+**
+** The checksum on pWal->hdr is updated before it is written.
+*/
+static void walIndexWriteHdr(Wal *pWal){
+ volatile WalIndexHdr *aHdr = walIndexHdr(pWal);
+ const int nCksum = offsetof(WalIndexHdr, aCksum);
+
+ assert( pWal->writeLock );
+ pWal->hdr.isInit = 1;
+ pWal->hdr.iVersion = WALINDEX_MAX_VERSION;
+ walChecksumBytes(1, (u8*)&pWal->hdr, nCksum, 0, pWal->hdr.aCksum);
+ memcpy((void *)&aHdr[1], (void *)&pWal->hdr, sizeof(WalIndexHdr));
+ walShmBarrier(pWal);
+ memcpy((void *)&aHdr[0], (void *)&pWal->hdr, sizeof(WalIndexHdr));
+}
+
+/*
+** This function encodes a single frame header and writes it to a buffer
+** supplied by the caller. A frame-header is made up of a series of
+** 4-byte big-endian integers, as follows:
+**
+** 0: Page number.
+** 4: For commit records, the size of the database image in pages
+** after the commit. For all other records, zero.
+** 8: Salt-1 (copied from the wal-header)
+** 12: Salt-2 (copied from the wal-header)
+** 16: Checksum-1.
+** 20: Checksum-2.
+*/
+static void walEncodeFrame(
+ Wal *pWal, /* The write-ahead log */
+ u32 iPage, /* Database page number for frame */
+ u32 nTruncate, /* New db size (or 0 for non-commit frames) */
+ u8 *aData, /* Pointer to page data */
+ u8 *aFrame /* OUT: Write encoded frame here */
+){
+ int nativeCksum; /* True for native byte-order checksums */
+ u32 *aCksum = pWal->hdr.aFrameCksum;
+ assert( WAL_FRAME_HDRSIZE==24 );
+ sqlite3Put4byte(&aFrame[0], iPage);
+ sqlite3Put4byte(&aFrame[4], nTruncate);
+ memcpy(&aFrame[8], pWal->hdr.aSalt, 8);
+
+ nativeCksum = (pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN);
+ walChecksumBytes(nativeCksum, aFrame, 8, aCksum, aCksum);
+ walChecksumBytes(nativeCksum, aData, pWal->szPage, aCksum, aCksum);
+
+ sqlite3Put4byte(&aFrame[16], aCksum[0]);
+ sqlite3Put4byte(&aFrame[20], aCksum[1]);
+}
+
+/*
+** Check to see if the frame with header in aFrame[] and content
+** in aData[] is valid. If it is a valid frame, fill *piPage and
+** *pnTruncate and return true. Return if the frame is not valid.
+*/
+static int walDecodeFrame(
+ Wal *pWal, /* The write-ahead log */
+ u32 *piPage, /* OUT: Database page number for frame */
+ u32 *pnTruncate, /* OUT: New db size (or 0 if not commit) */
+ u8 *aData, /* Pointer to page data (for checksum) */
+ u8 *aFrame /* Frame data */
+){
+ int nativeCksum; /* True for native byte-order checksums */
+ u32 *aCksum = pWal->hdr.aFrameCksum;
+ u32 pgno; /* Page number of the frame */
+ assert( WAL_FRAME_HDRSIZE==24 );
+
+ /* A frame is only valid if the salt values in the frame-header
+ ** match the salt values in the wal-header.
+ */
+ if( memcmp(&pWal->hdr.aSalt, &aFrame[8], 8)!=0 ){
+ return 0;
+ }
+
+ /* A frame is only valid if the page number is creater than zero.
+ */
+ pgno = sqlite3Get4byte(&aFrame[0]);
+ if( pgno==0 ){
+ return 0;
+ }
+
+ /* A frame is only valid if a checksum of the WAL header,
+ ** all prior frams, the first 16 bytes of this frame-header,
+ ** and the frame-data matches the checksum in the last 8
+ ** bytes of this frame-header.
+ */
+ nativeCksum = (pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN);
+ walChecksumBytes(nativeCksum, aFrame, 8, aCksum, aCksum);
+ walChecksumBytes(nativeCksum, aData, pWal->szPage, aCksum, aCksum);
+ if( aCksum[0]!=sqlite3Get4byte(&aFrame[16])
+ || aCksum[1]!=sqlite3Get4byte(&aFrame[20])
+ ){
+ /* Checksum failed. */
+ return 0;
+ }
+
+ /* If we reach this point, the frame is valid. Return the page number
+ ** and the new database size.
+ */
+ *piPage = pgno;
+ *pnTruncate = sqlite3Get4byte(&aFrame[4]);
+ return 1;
+}
+
+
+#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
+/*
+** Names of locks. This routine is used to provide debugging output and is not
+** a part of an ordinary build.
+*/
+static const char *walLockName(int lockIdx){
+ if( lockIdx==WAL_WRITE_LOCK ){
+ return "WRITE-LOCK";
+ }else if( lockIdx==WAL_CKPT_LOCK ){
+ return "CKPT-LOCK";
+ }else if( lockIdx==WAL_RECOVER_LOCK ){
+ return "RECOVER-LOCK";
+ }else{
+ static char zName[15];
+ sqlite3_snprintf(sizeof(zName), zName, "READ-LOCK[%d]",
+ lockIdx-WAL_READ_LOCK(0));
+ return zName;
+ }
+}
+#endif /*defined(SQLITE_TEST) || defined(SQLITE_DEBUG) */
+
+
+/*
+** Set or release locks on the WAL. Locks are either shared or exclusive.
+** A lock cannot be moved directly between shared and exclusive - it must go
+** through the unlocked state first.
+**
+** In locking_mode=EXCLUSIVE, all of these routines become no-ops.
+*/
+static int walLockShared(Wal *pWal, int lockIdx){
+ int rc;
+ if( pWal->exclusiveMode ) return SQLITE_OK;
+ rc = sqlite3OsShmLock(pWal->pDbFd, lockIdx, 1,
+ SQLITE_SHM_LOCK | SQLITE_SHM_SHARED);
+ WALTRACE(("WAL%p: acquire SHARED-%s %s\n", pWal,
+ walLockName(lockIdx), rc ? "failed" : "ok"));
+ VVA_ONLY( pWal->lockError = (u8)(rc!=SQLITE_OK && rc!=SQLITE_BUSY); )
+ return rc;
+}
+static void walUnlockShared(Wal *pWal, int lockIdx){
+ if( pWal->exclusiveMode ) return;
+ (void)sqlite3OsShmLock(pWal->pDbFd, lockIdx, 1,
+ SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED);
+ WALTRACE(("WAL%p: release SHARED-%s\n", pWal, walLockName(lockIdx)));
+}
+static int walLockExclusive(Wal *pWal, int lockIdx, int n){
+ int rc;
+ if( pWal->exclusiveMode ) return SQLITE_OK;
+ rc = sqlite3OsShmLock(pWal->pDbFd, lockIdx, n,
+ SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE);
+ WALTRACE(("WAL%p: acquire EXCLUSIVE-%s cnt=%d %s\n", pWal,
+ walLockName(lockIdx), n, rc ? "failed" : "ok"));
+ VVA_ONLY( pWal->lockError = (u8)(rc!=SQLITE_OK && rc!=SQLITE_BUSY); )
+ return rc;
+}
+static void walUnlockExclusive(Wal *pWal, int lockIdx, int n){
+ if( pWal->exclusiveMode ) return;
+ (void)sqlite3OsShmLock(pWal->pDbFd, lockIdx, n,
+ SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE);
+ WALTRACE(("WAL%p: release EXCLUSIVE-%s cnt=%d\n", pWal,
+ walLockName(lockIdx), n));
+}
+
+/*
+** Compute a hash on a page number. The resulting hash value must land
+** between 0 and (HASHTABLE_NSLOT-1). The walHashNext() function advances
+** the hash to the next value in the event of a collision.
+*/
+static int walHash(u32 iPage){
+ assert( iPage>0 );
+ assert( (HASHTABLE_NSLOT & (HASHTABLE_NSLOT-1))==0 );
+ return (iPage*HASHTABLE_HASH_1) & (HASHTABLE_NSLOT-1);
+}
+static int walNextHash(int iPriorHash){
+ return (iPriorHash+1)&(HASHTABLE_NSLOT-1);
+}
+
+/*
+** Return pointers to the hash table and page number array stored on
+** page iHash of the wal-index. The wal-index is broken into 32KB pages
+** numbered starting from 0.
+**
+** Set output variable *paHash to point to the start of the hash table
+** in the wal-index file. Set *piZero to one less than the frame
+** number of the first frame indexed by this hash table. If a
+** slot in the hash table is set to N, it refers to frame number
+** (*piZero+N) in the log.
+**
+** Finally, set *paPgno so that *paPgno[1] is the page number of the
+** first frame indexed by the hash table, frame (*piZero+1).
+*/
+static int walHashGet(
+ Wal *pWal, /* WAL handle */
+ int iHash, /* Find the iHash'th table */
+ volatile ht_slot **paHash, /* OUT: Pointer to hash index */
+ volatile u32 **paPgno, /* OUT: Pointer to page number array */
+ u32 *piZero /* OUT: Frame associated with *paPgno[0] */
+){
+ int rc; /* Return code */
+ volatile u32 *aPgno;
+
+ rc = walIndexPage(pWal, iHash, &aPgno);
+ assert( rc==SQLITE_OK || iHash>0 );
+
+ if( rc==SQLITE_OK ){
+ u32 iZero;
+ volatile ht_slot *aHash;
+
+ aHash = (volatile ht_slot *)&aPgno[HASHTABLE_NPAGE];
+ if( iHash==0 ){
+ aPgno = &aPgno[WALINDEX_HDR_SIZE/sizeof(u32)];
+ iZero = 0;
+ }else{
+ iZero = HASHTABLE_NPAGE_ONE + (iHash-1)*HASHTABLE_NPAGE;
+ }
+
+ *paPgno = &aPgno[-1];
+ *paHash = aHash;
+ *piZero = iZero;
+ }
+ return rc;
+}
+
+/*
+** Return the number of the wal-index page that contains the hash-table
+** and page-number array that contain entries corresponding to WAL frame
+** iFrame. The wal-index is broken up into 32KB pages. Wal-index pages
+** are numbered starting from 0.
+*/
+static int walFramePage(u32 iFrame){
+ int iHash = (iFrame+HASHTABLE_NPAGE-HASHTABLE_NPAGE_ONE-1) / HASHTABLE_NPAGE;
+ assert( (iHash==0 || iFrame>HASHTABLE_NPAGE_ONE)
+ && (iHash>=1 || iFrame<=HASHTABLE_NPAGE_ONE)
+ && (iHash<=1 || iFrame>(HASHTABLE_NPAGE_ONE+HASHTABLE_NPAGE))
+ && (iHash>=2 || iFrame<=HASHTABLE_NPAGE_ONE+HASHTABLE_NPAGE)
+ && (iHash<=2 || iFrame>(HASHTABLE_NPAGE_ONE+2*HASHTABLE_NPAGE))
+ );
+ return iHash;
+}
+
+/*
+** Return the page number associated with frame iFrame in this WAL.
+*/
+static u32 walFramePgno(Wal *pWal, u32 iFrame){
+ int iHash = walFramePage(iFrame);
+ if( iHash==0 ){
+ return pWal->apWiData[0][WALINDEX_HDR_SIZE/sizeof(u32) + iFrame - 1];
+ }
+ return pWal->apWiData[iHash][(iFrame-1-HASHTABLE_NPAGE_ONE)%HASHTABLE_NPAGE];
+}
+
+/*
+** Remove entries from the hash table that point to WAL slots greater
+** than pWal->hdr.mxFrame.
+**
+** This function is called whenever pWal->hdr.mxFrame is decreased due
+** to a rollback or savepoint.
+**
+** At most only the hash table containing pWal->hdr.mxFrame needs to be
+** updated. Any later hash tables will be automatically cleared when
+** pWal->hdr.mxFrame advances to the point where those hash tables are
+** actually needed.
+*/
+static void walCleanupHash(Wal *pWal){
+ volatile ht_slot *aHash = 0; /* Pointer to hash table to clear */
+ volatile u32 *aPgno = 0; /* Page number array for hash table */
+ u32 iZero = 0; /* frame == (aHash[x]+iZero) */
+ int iLimit = 0; /* Zero values greater than this */
+ int nByte; /* Number of bytes to zero in aPgno[] */
+ int i; /* Used to iterate through aHash[] */
+
+ assert( pWal->writeLock );
+ testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE-1 );
+ testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE );
+ testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE+1 );
+
+ if( pWal->hdr.mxFrame==0 ) return;
+
+ /* Obtain pointers to the hash-table and page-number array containing
+ ** the entry that corresponds to frame pWal->hdr.mxFrame. It is guaranteed
+ ** that the page said hash-table and array reside on is already mapped.
+ */
+ assert( pWal->nWiData>walFramePage(pWal->hdr.mxFrame) );
+ assert( pWal->apWiData[walFramePage(pWal->hdr.mxFrame)] );
+ walHashGet(pWal, walFramePage(pWal->hdr.mxFrame), &aHash, &aPgno, &iZero);
+
+ /* Zero all hash-table entries that correspond to frame numbers greater
+ ** than pWal->hdr.mxFrame.
+ */
+ iLimit = pWal->hdr.mxFrame - iZero;
+ assert( iLimit>0 );
+ for(i=0; iiLimit ){
+ aHash[i] = 0;
+ }
+ }
+
+ /* Zero the entries in the aPgno array that correspond to frames with
+ ** frame numbers greater than pWal->hdr.mxFrame.
+ */
+ nByte = (int)((char *)aHash - (char *)&aPgno[iLimit+1]);
+ memset((void *)&aPgno[iLimit+1], 0, nByte);
+
+#ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT
+ /* Verify that the every entry in the mapping region is still reachable
+ ** via the hash table even after the cleanup.
+ */
+ if( iLimit ){
+ int i; /* Loop counter */
+ int iKey; /* Hash key */
+ for(i=1; i<=iLimit; i++){
+ for(iKey=walHash(aPgno[i]); aHash[iKey]; iKey=walNextHash(iKey)){
+ if( aHash[iKey]==i ) break;
+ }
+ assert( aHash[iKey]==i );
+ }
+ }
+#endif /* SQLITE_ENABLE_EXPENSIVE_ASSERT */
+}
+
+
+/*
+** Set an entry in the wal-index that will map database page number
+** pPage into WAL frame iFrame.
+*/
+static int walIndexAppend(Wal *pWal, u32 iFrame, u32 iPage){
+ int rc; /* Return code */
+ u32 iZero = 0; /* One less than frame number of aPgno[1] */
+ volatile u32 *aPgno = 0; /* Page number array */
+ volatile ht_slot *aHash = 0; /* Hash table */
+
+ rc = walHashGet(pWal, walFramePage(iFrame), &aHash, &aPgno, &iZero);
+
+ /* Assuming the wal-index file was successfully mapped, populate the
+ ** page number array and hash table entry.
+ */
+ if( rc==SQLITE_OK ){
+ int iKey; /* Hash table key */
+ int idx; /* Value to write to hash-table slot */
+ int nCollide; /* Number of hash collisions */
+
+ idx = iFrame - iZero;
+ assert( idx <= HASHTABLE_NSLOT/2 + 1 );
+
+ /* If this is the first entry to be added to this hash-table, zero the
+ ** entire hash table and aPgno[] array before proceding.
+ */
+ if( idx==1 ){
+ int nByte = (int)((u8 *)&aHash[HASHTABLE_NSLOT] - (u8 *)&aPgno[1]);
+ memset((void*)&aPgno[1], 0, nByte);
+ }
+
+ /* If the entry in aPgno[] is already set, then the previous writer
+ ** must have exited unexpectedly in the middle of a transaction (after
+ ** writing one or more dirty pages to the WAL to free up memory).
+ ** Remove the remnants of that writers uncommitted transaction from
+ ** the hash-table before writing any new entries.
+ */
+ if( aPgno[idx] ){
+ walCleanupHash(pWal);
+ assert( !aPgno[idx] );
+ }
+
+ /* Write the aPgno[] array entry and the hash-table slot. */
+ nCollide = idx;
+ for(iKey=walHash(iPage); aHash[iKey]; iKey=walNextHash(iKey)){
+ if( (nCollide--)==0 ) return SQLITE_CORRUPT_BKPT;
+ }
+ aPgno[idx] = iPage;
+ aHash[iKey] = (ht_slot)idx;
+
+#ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT
+ /* Verify that the number of entries in the hash table exactly equals
+ ** the number of entries in the mapping region.
+ */
+ {
+ int i; /* Loop counter */
+ int nEntry = 0; /* Number of entries in the hash table */
+ for(i=0; ickptLock==1 || pWal->ckptLock==0 );
+ assert( WAL_ALL_BUT_WRITE==WAL_WRITE_LOCK+1 );
+ assert( WAL_CKPT_LOCK==WAL_ALL_BUT_WRITE );
+ assert( pWal->writeLock );
+ iLock = WAL_ALL_BUT_WRITE + pWal->ckptLock;
+ nLock = SQLITE_SHM_NLOCK - iLock;
+ rc = walLockExclusive(pWal, iLock, nLock);
+ if( rc ){
+ return rc;
+ }
+ WALTRACE(("WAL%p: recovery begin...\n", pWal));
+
+ memset(&pWal->hdr, 0, sizeof(WalIndexHdr));
+
+ rc = sqlite3OsFileSize(pWal->pWalFd, &nSize);
+ if( rc!=SQLITE_OK ){
+ goto recovery_error;
+ }
+
+ if( nSize>WAL_HDRSIZE ){
+ u8 aBuf[WAL_HDRSIZE]; /* Buffer to load WAL header into */
+ u8 *aFrame = 0; /* Malloc'd buffer to load entire frame */
+ int szFrame; /* Number of bytes in buffer aFrame[] */
+ u8 *aData; /* Pointer to data part of aFrame buffer */
+ int iFrame; /* Index of last frame read */
+ i64 iOffset; /* Next offset to read from log file */
+ int szPage; /* Page size according to the log */
+ u32 magic; /* Magic value read from WAL header */
+ u32 version; /* Magic value read from WAL header */
+ int isValid; /* True if this frame is valid */
+
+ /* Read in the WAL header. */
+ rc = sqlite3OsRead(pWal->pWalFd, aBuf, WAL_HDRSIZE, 0);
+ if( rc!=SQLITE_OK ){
+ goto recovery_error;
+ }
+
+ /* If the database page size is not a power of two, or is greater than
+ ** SQLITE_MAX_PAGE_SIZE, conclude that the WAL file contains no valid
+ ** data. Similarly, if the 'magic' value is invalid, ignore the whole
+ ** WAL file.
+ */
+ magic = sqlite3Get4byte(&aBuf[0]);
+ szPage = sqlite3Get4byte(&aBuf[8]);
+ if( (magic&0xFFFFFFFE)!=WAL_MAGIC
+ || szPage&(szPage-1)
+ || szPage>SQLITE_MAX_PAGE_SIZE
+ || szPage<512
+ ){
+ goto finished;
+ }
+ pWal->hdr.bigEndCksum = (u8)(magic&0x00000001);
+ pWal->szPage = szPage;
+ pWal->nCkpt = sqlite3Get4byte(&aBuf[12]);
+ memcpy(&pWal->hdr.aSalt, &aBuf[16], 8);
+
+ /* Verify that the WAL header checksum is correct */
+ walChecksumBytes(pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN,
+ aBuf, WAL_HDRSIZE-2*4, 0, pWal->hdr.aFrameCksum
+ );
+ if( pWal->hdr.aFrameCksum[0]!=sqlite3Get4byte(&aBuf[24])
+ || pWal->hdr.aFrameCksum[1]!=sqlite3Get4byte(&aBuf[28])
+ ){
+ goto finished;
+ }
+
+ /* Verify that the version number on the WAL format is one that
+ ** are able to understand */
+ version = sqlite3Get4byte(&aBuf[4]);
+ if( version!=WAL_MAX_VERSION ){
+ rc = SQLITE_CANTOPEN_BKPT;
+ goto finished;
+ }
+
+ /* Malloc a buffer to read frames into. */
+ szFrame = szPage + WAL_FRAME_HDRSIZE;
+ aFrame = (u8 *)sqlite3_malloc(szFrame);
+ if( !aFrame ){
+ rc = SQLITE_NOMEM;
+ goto recovery_error;
+ }
+ aData = &aFrame[WAL_FRAME_HDRSIZE];
+
+ /* Read all frames from the log file. */
+ iFrame = 0;
+ for(iOffset=WAL_HDRSIZE; (iOffset+szFrame)<=nSize; iOffset+=szFrame){
+ u32 pgno; /* Database page number for frame */
+ u32 nTruncate; /* dbsize field from frame header */
+
+ /* Read and decode the next log frame. */
+ iFrame++;
+ rc = sqlite3OsRead(pWal->pWalFd, aFrame, szFrame, iOffset);
+ if( rc!=SQLITE_OK ) break;
+ isValid = walDecodeFrame(pWal, &pgno, &nTruncate, aData, aFrame);
+ if( !isValid ) break;
+ rc = walIndexAppend(pWal, iFrame, pgno);
+ if( rc!=SQLITE_OK ) break;
+
+ /* If nTruncate is non-zero, this is a commit record. */
+ if( nTruncate ){
+ pWal->hdr.mxFrame = iFrame;
+ pWal->hdr.nPage = nTruncate;
+ pWal->hdr.szPage = (u16)((szPage&0xff00) | (szPage>>16));
+ testcase( szPage<=32768 );
+ testcase( szPage>=65536 );
+ aFrameCksum[0] = pWal->hdr.aFrameCksum[0];
+ aFrameCksum[1] = pWal->hdr.aFrameCksum[1];
+ }
+ }
+
+ sqlite3_free(aFrame);
+ }
+
+finished:
+ if( rc==SQLITE_OK ){
+ volatile WalCkptInfo *pInfo;
+ int i;
+ pWal->hdr.aFrameCksum[0] = aFrameCksum[0];
+ pWal->hdr.aFrameCksum[1] = aFrameCksum[1];
+ walIndexWriteHdr(pWal);
+
+ /* Reset the checkpoint-header. This is safe because this thread is
+ ** currently holding locks that exclude all other readers, writers and
+ ** checkpointers.
+ */
+ pInfo = walCkptInfo(pWal);
+ pInfo->nBackfill = 0;
+ pInfo->aReadMark[0] = 0;
+ for(i=1; iaReadMark[i] = READMARK_NOT_USED;
+ if( pWal->hdr.mxFrame ) pInfo->aReadMark[1] = pWal->hdr.mxFrame;
+
+ /* If more than one frame was recovered from the log file, report an
+ ** event via sqlite3_log(). This is to help with identifying performance
+ ** problems caused by applications routinely shutting down without
+ ** checkpointing the log file.
+ */
+ if( pWal->hdr.nPage ){
+ sqlite3_log(SQLITE_NOTICE_RECOVER_WAL,
+ "recovered %d frames from WAL file %s",
+ pWal->hdr.mxFrame, pWal->zWalName
+ );
+ }
+ }
+
+recovery_error:
+ WALTRACE(("WAL%p: recovery %s\n", pWal, rc ? "failed" : "ok"));
+ walUnlockExclusive(pWal, iLock, nLock);
+ return rc;
+}
+
+/*
+** Close an open wal-index.
+*/
+static void walIndexClose(Wal *pWal, int isDelete){
+ if( pWal->exclusiveMode==WAL_HEAPMEMORY_MODE ){
+ int i;
+ for(i=0; inWiData; i++){
+ sqlite3_free((void *)pWal->apWiData[i]);
+ pWal->apWiData[i] = 0;
+ }
+ }else{
+ sqlite3OsShmUnmap(pWal->pDbFd, isDelete);
+ }
+}
+
+/*
+** Open a connection to the WAL file zWalName. The database file must
+** already be opened on connection pDbFd. The buffer that zWalName points
+** to must remain valid for the lifetime of the returned Wal* handle.
+**
+** A SHARED lock should be held on the database file when this function
+** is called. The purpose of this SHARED lock is to prevent any other
+** client from unlinking the WAL or wal-index file. If another process
+** were to do this just after this client opened one of these files, the
+** system would be badly broken.
+**
+** If the log file is successfully opened, SQLITE_OK is returned and
+** *ppWal is set to point to a new WAL handle. If an error occurs,
+** an SQLite error code is returned and *ppWal is left unmodified.
+*/
+SQLITE_PRIVATE int sqlite3WalOpen(
+ sqlite3_vfs *pVfs, /* vfs module to open wal and wal-index */
+ sqlite3_file *pDbFd, /* The open database file */
+ const char *zWalName, /* Name of the WAL file */
+ int bNoShm, /* True to run in heap-memory mode */
+ i64 mxWalSize, /* Truncate WAL to this size on reset */
+ Wal **ppWal /* OUT: Allocated Wal handle */
+){
+ int rc; /* Return Code */
+ Wal *pRet; /* Object to allocate and return */
+ int flags; /* Flags passed to OsOpen() */
+
+ assert( zWalName && zWalName[0] );
+ assert( pDbFd );
+
+ /* In the amalgamation, the os_unix.c and os_win.c source files come before
+ ** this source file. Verify that the #defines of the locking byte offsets
+ ** in os_unix.c and os_win.c agree with the WALINDEX_LOCK_OFFSET value.
+ */
+#ifdef WIN_SHM_BASE
+ assert( WIN_SHM_BASE==WALINDEX_LOCK_OFFSET );
+#endif
+#ifdef UNIX_SHM_BASE
+ assert( UNIX_SHM_BASE==WALINDEX_LOCK_OFFSET );
+#endif
+
+
+ /* Allocate an instance of struct Wal to return. */
+ *ppWal = 0;
+ pRet = (Wal*)sqlite3MallocZero(sizeof(Wal) + pVfs->szOsFile);
+ if( !pRet ){
+ return SQLITE_NOMEM;
+ }
+
+ pRet->pVfs = pVfs;
+ pRet->pWalFd = (sqlite3_file *)&pRet[1];
+ pRet->pDbFd = pDbFd;
+ pRet->readLock = -1;
+ pRet->mxWalSize = mxWalSize;
+ pRet->zWalName = zWalName;
+ pRet->syncHeader = 1;
+ pRet->padToSectorBoundary = 1;
+ pRet->exclusiveMode = (bNoShm ? WAL_HEAPMEMORY_MODE: WAL_NORMAL_MODE);
+
+ /* Open file handle on the write-ahead log file. */
+ flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_WAL);
+ rc = sqlite3OsOpen(pVfs, zWalName, pRet->pWalFd, flags, &flags);
+ if( rc==SQLITE_OK && flags&SQLITE_OPEN_READONLY ){
+ pRet->readOnly = WAL_RDONLY;
+ }
+
+ if( rc!=SQLITE_OK ){
+ walIndexClose(pRet, 0);
+ sqlite3OsClose(pRet->pWalFd);
+ sqlite3_free(pRet);
+ }else{
+ int iDC = sqlite3OsDeviceCharacteristics(pDbFd);
+ if( iDC & SQLITE_IOCAP_SEQUENTIAL ){ pRet->syncHeader = 0; }
+ if( iDC & SQLITE_IOCAP_POWERSAFE_OVERWRITE ){
+ pRet->padToSectorBoundary = 0;
+ }
+ *ppWal = pRet;
+ WALTRACE(("WAL%d: opened\n", pRet));
+ }
+ return rc;
+}
+
+/*
+** Change the size to which the WAL file is trucated on each reset.
+*/
+SQLITE_PRIVATE void sqlite3WalLimit(Wal *pWal, i64 iLimit){
+ if( pWal ) pWal->mxWalSize = iLimit;
+}
+
+/*
+** Find the smallest page number out of all pages held in the WAL that
+** has not been returned by any prior invocation of this method on the
+** same WalIterator object. Write into *piFrame the frame index where
+** that page was last written into the WAL. Write into *piPage the page
+** number.
+**
+** Return 0 on success. If there are no pages in the WAL with a page
+** number larger than *piPage, then return 1.
+*/
+static int walIteratorNext(
+ WalIterator *p, /* Iterator */
+ u32 *piPage, /* OUT: The page number of the next page */
+ u32 *piFrame /* OUT: Wal frame index of next page */
+){
+ u32 iMin; /* Result pgno must be greater than iMin */
+ u32 iRet = 0xFFFFFFFF; /* 0xffffffff is never a valid page number */
+ int i; /* For looping through segments */
+
+ iMin = p->iPrior;
+ assert( iMin<0xffffffff );
+ for(i=p->nSegment-1; i>=0; i--){
+ struct WalSegment *pSegment = &p->aSegment[i];
+ while( pSegment->iNextnEntry ){
+ u32 iPg = pSegment->aPgno[pSegment->aIndex[pSegment->iNext]];
+ if( iPg>iMin ){
+ if( iPgiZero + pSegment->aIndex[pSegment->iNext];
+ }
+ break;
+ }
+ pSegment->iNext++;
+ }
+ }
+
+ *piPage = p->iPrior = iRet;
+ return (iRet==0xFFFFFFFF);
+}
+
+/*
+** This function merges two sorted lists into a single sorted list.
+**
+** aLeft[] and aRight[] are arrays of indices. The sort key is
+** aContent[aLeft[]] and aContent[aRight[]]. Upon entry, the following
+** is guaranteed for all J0 && nRight>0 );
+ while( iRight