gstreamer/plugins/elements/gstfilesrc.c
Tim-Philipp Müller 6cd3b9de71 plugins/elements/gstfilesrc.c: Requesting 0 bytes before the end of the file should result in
Original commit message from CVS:
* plugins/elements/gstfilesrc.c: (gst_file_src_create_read):
Requesting 0 bytes before the end of the file should result in
FLOW_OK and an empty buffer, not FLOW_UNEXPECTED. Thank you
unit test.
2006-07-27 12:39:42 +00:00

1080 lines
30 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000,2005 Wim Taymans <wim@fluendo.com>
*
* gstfilesrc.c:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-filesrc
* @short_description: read from arbitrary point in a file
* @see_also: #GstFileSrc
*
* Read data from a file in the local file system.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <gst/gst.h>
#include "gstfilesrc.h"
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_MMAP
# include <sys/mman.h>
#endif
#ifdef HAVE_WIN32
# include <io.h> /* lseek, open, close, read */
#endif
#include <errno.h>
#include <string.h>
#include "../../gst/gst-i18n-lib.h"
static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
/* FIXME we should be using glib for this */
#ifndef S_ISREG
#define S_ISREG(mode) ((mode)&_S_IFREG)
#endif
#ifndef S_ISDIR
#define S_ISDIR(mode) ((mode)&_S_IFDIR)
#endif
#ifndef S_ISSOCK
#define S_ISSOCK(x) (0)
#endif
#ifndef O_BINARY
#define O_BINARY (0)
#endif
/**********************************************************************
* GStreamer Default File Source
* Theory of Operation
*
* Update: see GstFileSrc:use-mmap property documentation below
* for why use of mmap() is disabled by default.
*
* This source uses mmap(2) to efficiently load data from a file.
* To do this without seriously polluting the applications' memory
* space, it must do so in smaller chunks, say 1-4MB at a time.
* Buffers are then subdivided from these mmap'd chunks, to directly
* make use of the mmap.
*
* To handle refcounting so that the mmap can be freed at the appropriate
* time, a buffer will be created for each mmap'd region, and all new
* buffers will be sub-buffers of this top-level buffer. As they are
* freed, the refcount goes down on the mmap'd buffer and its free()
* function is called, which will call munmap(2) on itself.
*
* If a buffer happens to cross the boundaries of an mmap'd region, we
* have to decide whether it's more efficient to copy the data into a
* new buffer, or mmap() just that buffer. There will have to be a
* breakpoint size to determine which will be done. The mmap() size
* has a lot to do with this as well, because you end up in double-
* jeopardy: the larger the outgoing buffer, the more data to copy when
* it overlaps, *and* the more frequently you'll have buffers that *do*
* overlap.
*
* Seeking is another tricky aspect to do efficiently. The initial
* implementation of this source won't make use of these features, however.
* The issue is that if an application seeks backwards in a file, *and*
* that region of the file is covered by an mmap that hasn't been fully
* deallocated, we really should re-use it. But keeping track of these
* regions is tricky because we have to lock the structure that holds
* them. We need to settle on a locking primitive (GMutex seems to be
* a really good option...), then we can do that.
*/
GST_DEBUG_CATEGORY_STATIC (gst_file_src_debug);
#define GST_CAT_DEFAULT gst_file_src_debug
static const GstElementDetails gst_file_src_details =
GST_ELEMENT_DETAILS ("File Source",
"Source/File",
"Read from arbitrary point in a file",
"Erik Walthinsen <omega@cse.ogi.edu>");
/* FileSrc signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_BLOCKSIZE 4*1024
#define DEFAULT_MMAPSIZE 4*1024*1024
#define DEFAULT_TOUCH TRUE
#define DEFAULT_USEMMAP FALSE
#define DEFAULT_SEQUENTIAL FALSE
enum
{
ARG_0,
ARG_LOCATION,
ARG_FD,
ARG_MMAPSIZE,
ARG_SEQUENTIAL,
ARG_TOUCH,
ARG_USEMMAP
};
static void gst_file_src_finalize (GObject * object);
static void gst_file_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_file_src_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_file_src_start (GstBaseSrc * basesrc);
static gboolean gst_file_src_stop (GstBaseSrc * basesrc);
static gboolean gst_file_src_is_seekable (GstBaseSrc * src);
static gboolean gst_file_src_get_size (GstBaseSrc * src, guint64 * size);
static GstFlowReturn gst_file_src_create (GstBaseSrc * src, guint64 offset,
guint length, GstBuffer ** buffer);
static void gst_file_src_uri_handler_init (gpointer g_iface,
gpointer iface_data);
static void
_do_init (GType filesrc_type)
{
static const GInterfaceInfo urihandler_info = {
gst_file_src_uri_handler_init,
NULL,
NULL
};
g_type_add_interface_static (filesrc_type, GST_TYPE_URI_HANDLER,
&urihandler_info);
GST_DEBUG_CATEGORY_INIT (gst_file_src_debug, "filesrc", 0, "filesrc element");
}
GST_BOILERPLATE_FULL (GstFileSrc, gst_file_src, GstBaseSrc, GST_TYPE_BASE_SRC,
_do_init);
static void
gst_file_src_base_init (gpointer g_class)
{
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&srctemplate));
gst_element_class_set_details (gstelement_class, &gst_file_src_details);
}
static void
gst_file_src_class_init (GstFileSrcClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstBaseSrcClass *gstbasesrc_class;
gobject_class = G_OBJECT_CLASS (klass);
gstelement_class = GST_ELEMENT_CLASS (klass);
gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
gobject_class->set_property = gst_file_src_set_property;
gobject_class->get_property = gst_file_src_get_property;
g_object_class_install_property (gobject_class, ARG_FD,
g_param_spec_int ("fd", "File-descriptor",
"File-descriptor for the file being mmap()d", 0, G_MAXINT, 0,
G_PARAM_READABLE));
g_object_class_install_property (gobject_class, ARG_LOCATION,
g_param_spec_string ("location", "File Location",
"Location of the file to read", NULL, G_PARAM_READWRITE));
g_object_class_install_property (gobject_class, ARG_MMAPSIZE,
g_param_spec_ulong ("mmapsize", "mmap() Block Size",
"Size in bytes of mmap()d regions", 0, G_MAXULONG, DEFAULT_MMAPSIZE,
G_PARAM_READWRITE));
g_object_class_install_property (gobject_class, ARG_TOUCH,
g_param_spec_boolean ("touch", "Touch mapped region read data",
"Touch mmapped data regions to force them to be read from disk",
DEFAULT_TOUCH, G_PARAM_READWRITE));
/**
* GstFileSrc:use-mmap
*
* Whether to use mmap(). Set to TRUE to force use of mmap() instead of
* read() for reading data.
*
* Use of mmap() is disabled by default since with mmap() there are a
* number of occasions where the process/application will be notified of
* read errors via a SIGBUS signal from the kernel, which will lead to
* the application being killed if not handled by the application. This
* is something that is difficult to work around for a library like
* GStreamer, hence use of mmap() is disabled by default. Said errors
* can occur for example when an external device (e.g. an external hard
* drive or a portable music player) are unplugged while in use, or when
* a CD/DVD medium cannot be be read because the medium is scratched or
* otherwise damaged.
*
**/
g_object_class_install_property (gobject_class, ARG_USEMMAP,
g_param_spec_boolean ("use-mmap", "Use mmap to read data",
"Whether to use mmap() instead of read()",
DEFAULT_USEMMAP, G_PARAM_READWRITE));
g_object_class_install_property (gobject_class, ARG_SEQUENTIAL,
g_param_spec_boolean ("sequential", "Optimise for sequential mmap access",
"Whether to use madvise to hint to the kernel that access to "
"mmap pages will be sequential",
DEFAULT_SEQUENTIAL, G_PARAM_READWRITE));
gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_file_src_finalize);
gstbasesrc_class->start = GST_DEBUG_FUNCPTR (gst_file_src_start);
gstbasesrc_class->stop = GST_DEBUG_FUNCPTR (gst_file_src_stop);
gstbasesrc_class->is_seekable = GST_DEBUG_FUNCPTR (gst_file_src_is_seekable);
gstbasesrc_class->get_size = GST_DEBUG_FUNCPTR (gst_file_src_get_size);
gstbasesrc_class->create = GST_DEBUG_FUNCPTR (gst_file_src_create);
if (sizeof (off_t) < 8) {
GST_LOG ("No large file support, sizeof (off_t) = %u!", sizeof (off_t));
}
}
static void
gst_file_src_init (GstFileSrc * src, GstFileSrcClass * g_class)
{
#ifdef HAVE_MMAP
src->pagesize = getpagesize ();
#endif
src->filename = NULL;
src->fd = 0;
src->uri = NULL;
src->touch = DEFAULT_TOUCH;
src->mapbuf = NULL;
src->mapsize = DEFAULT_MMAPSIZE; /* default is 4MB */
src->use_mmap = DEFAULT_USEMMAP;
src->sequential = DEFAULT_SEQUENTIAL;
src->is_regular = FALSE;
}
static void
gst_file_src_finalize (GObject * object)
{
GstFileSrc *src;
src = GST_FILE_SRC (object);
g_free (src->filename);
g_free (src->uri);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static gboolean
gst_file_src_set_location (GstFileSrc * src, const gchar * location)
{
/* the element must be stopped in order to do this */
GST_STATE_LOCK (src);
{
GstState state;
state = GST_STATE (src);
if (state != GST_STATE_READY && state != GST_STATE_NULL)
goto wrong_state;
}
GST_STATE_UNLOCK (src);
g_free (src->filename);
g_free (src->uri);
/* clear the filename if we get a NULL (is that possible?) */
if (location == NULL) {
src->filename = NULL;
src->uri = NULL;
} else {
src->filename = g_strdup (location);
src->uri = gst_uri_construct ("file", src->filename);
}
g_object_notify (G_OBJECT (src), "location");
gst_uri_handler_new_uri (GST_URI_HANDLER (src), src->uri);
return TRUE;
/* ERROR */
wrong_state:
{
GST_DEBUG_OBJECT (src, "setting location in wrong state");
GST_STATE_UNLOCK (src);
return FALSE;
}
}
static void
gst_file_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstFileSrc *src;
g_return_if_fail (GST_IS_FILE_SRC (object));
src = GST_FILE_SRC (object);
switch (prop_id) {
case ARG_LOCATION:
gst_file_src_set_location (src, g_value_get_string (value));
break;
case ARG_MMAPSIZE:
if ((src->mapsize % src->pagesize) == 0) {
src->mapsize = g_value_get_ulong (value);
} else {
GST_INFO_OBJECT (src,
"invalid mapsize, must be a multiple of pagesize, which is %d",
src->pagesize);
}
break;
case ARG_TOUCH:
src->touch = g_value_get_boolean (value);
break;
case ARG_SEQUENTIAL:
src->sequential = g_value_get_boolean (value);
break;
case ARG_USEMMAP:
src->use_mmap = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_file_src_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstFileSrc *src;
g_return_if_fail (GST_IS_FILE_SRC (object));
src = GST_FILE_SRC (object);
switch (prop_id) {
case ARG_LOCATION:
g_value_set_string (value, src->filename);
break;
case ARG_FD:
g_value_set_int (value, src->fd);
break;
case ARG_MMAPSIZE:
g_value_set_ulong (value, src->mapsize);
break;
case ARG_TOUCH:
g_value_set_boolean (value, src->touch);
break;
case ARG_SEQUENTIAL:
g_value_set_boolean (value, src->sequential);
break;
case ARG_USEMMAP:
g_value_set_boolean (value, src->use_mmap);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/***
* mmap code below
*/
#ifdef HAVE_MMAP
/* GstMmapBuffer */
typedef struct _GstMmapBuffer GstMmapBuffer;
typedef struct _GstMmapBufferClass GstMmapBufferClass;
#define GST_TYPE_MMAP_BUFFER (gst_mmap_buffer_get_type())
#define GST_IS_MMAP_BUFFER(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_MMAP_BUFFER))
#define GST_IS_MMAP_BUFFER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_MMAP_BUFFER))
#define GST_MMAP_BUFFER_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_MMAP_BUFFER, GstMmapBufferClass))
#define GST_MMAP_BUFFER(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_MMAP_BUFFER, GstMmapBuffer))
#define GST_MMAP_BUFFER_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_MMAP_BUFFER, GstMmapBufferClass))
struct _GstMmapBuffer
{
GstBuffer buffer;
GstFileSrc *filesrc;
};
struct _GstMmapBufferClass
{
GstBufferClass buffer_class;
};
static void gst_mmap_buffer_init (GTypeInstance * instance, gpointer g_class);
static void gst_mmap_buffer_class_init (gpointer g_class, gpointer class_data);
static void gst_mmap_buffer_finalize (GstMmapBuffer * mmap_buffer);
static GType
gst_mmap_buffer_get_type (void)
{
static GType _gst_mmap_buffer_type;
if (G_UNLIKELY (_gst_mmap_buffer_type == 0)) {
static const GTypeInfo mmap_buffer_info = {
sizeof (GstMmapBufferClass),
NULL,
NULL,
gst_mmap_buffer_class_init,
NULL,
NULL,
sizeof (GstMmapBuffer),
0,
gst_mmap_buffer_init,
NULL
};
_gst_mmap_buffer_type = g_type_register_static (GST_TYPE_BUFFER,
"GstMmapBuffer", &mmap_buffer_info, 0);
}
return _gst_mmap_buffer_type;
}
static void
gst_mmap_buffer_class_init (gpointer g_class, gpointer class_data)
{
GstMiniObjectClass *mini_object_class = GST_MINI_OBJECT_CLASS (g_class);
mini_object_class->finalize =
(GstMiniObjectFinalizeFunction) gst_mmap_buffer_finalize;
}
static void
gst_mmap_buffer_init (GTypeInstance * instance, gpointer g_class)
{
GstBuffer *buf = (GstBuffer *) instance;
GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_READONLY);
/* before we re-enable this flag, we probably need to fix _copy()
* _make_writable(), etc. in GstMiniObject/GstBuffer as well */
/* GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_ORIGINAL); */
}
static void
gst_mmap_buffer_finalize (GstMmapBuffer * mmap_buffer)
{
guint size;
gpointer data;
guint64 offset;
GstFileSrc *src;
GstBuffer *buffer = GST_BUFFER (mmap_buffer);
/* get info */
size = GST_BUFFER_SIZE (buffer);
offset = GST_BUFFER_OFFSET (buffer);
data = GST_BUFFER_DATA (buffer);
src = mmap_buffer->filesrc;
GST_LOG ("freeing mmap()d buffer at %" G_GUINT64_FORMAT "+%u", offset, size);
#ifdef MADV_DONTNEED
/* madvise to tell the kernel what to do with it */
if (madvise (data, size, MADV_DONTNEED) < 0) {
GST_WARNING_OBJECT (src, "warning: madvise failed: %s", strerror (errno));
}
#endif
/* now unmap the memory */
if (munmap (data, size) < 0) {
GST_WARNING_OBJECT (src, "warning: munmap failed: %s", strerror (errno));
}
/* cast to unsigned long, since there's no gportable way to print
* guint64 as hex */
GST_LOG ("unmapped region %08lx+%08lx at %p",
(gulong) offset, (gulong) size, data);
}
static GstBuffer *
gst_file_src_map_region (GstFileSrc * src, off_t offset, size_t size,
gboolean testonly)
{
GstBuffer *buf;
void *mmapregion;
g_return_val_if_fail (offset >= 0, NULL);
GST_LOG_OBJECT (src, "mapping region %08llx+%08lx from file into memory",
offset, (gulong) size);
mmapregion = mmap (NULL, size, PROT_READ, MAP_SHARED, src->fd, offset);
if (mmapregion == NULL || mmapregion == MAP_FAILED)
goto mmap_failed;
GST_LOG_OBJECT (src, "mapped region %08lx+%08lx from file into memory at %p",
(gulong) offset, (gulong) size, mmapregion);
/* time to allocate a new mapbuf */
buf = (GstBuffer *) gst_mini_object_new (GST_TYPE_MMAP_BUFFER);
/* mmap() the data into this new buffer */
GST_BUFFER_DATA (buf) = mmapregion;
GST_MMAP_BUFFER (buf)->filesrc = src;
#ifdef MADV_SEQUENTIAL
if (src->sequential) {
/* madvise to tell the kernel what to do with it */
if (madvise (mmapregion, size, MADV_SEQUENTIAL) < 0) {
GST_WARNING_OBJECT (src, "warning: madvise failed: %s", strerror (errno));
}
}
#endif
/* fill in the rest of the fields */
GST_BUFFER_SIZE (buf) = size;
GST_BUFFER_OFFSET (buf) = offset;
GST_BUFFER_OFFSET_END (buf) = offset + size;
GST_BUFFER_TIMESTAMP (buf) = GST_CLOCK_TIME_NONE;
return buf;
/* ERROR */
mmap_failed:
{
if (!testonly) {
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ, (NULL),
("mmap (0x%08lx, %d, 0x%llx) failed: %s",
(gulong) size, src->fd, offset, strerror (errno)));
}
return NULL;
}
}
static GstBuffer *
gst_file_src_map_small_region (GstFileSrc * src, off_t offset, size_t size)
{
GstBuffer *ret;
off_t mod;
guint pagesize;
GST_LOG_OBJECT (src,
"attempting to map a small buffer at %llu+%d",
(unsigned long long) offset, (gint) size);
pagesize = src->pagesize;
mod = offset % pagesize;
/* if the offset starts at a non-page boundary, we have to special case */
if (mod != 0) {
size_t mapsize;
off_t mapbase;
GstBuffer *map;
mapbase = offset - mod;
mapsize = ((size + mod + pagesize - 1) / pagesize) * pagesize;
GST_LOG_OBJECT (src,
"not on page boundaries, resizing to map to %llu+%d",
(unsigned long long) mapbase, (gint) mapsize);
map = gst_file_src_map_region (src, mapbase, mapsize, FALSE);
if (map == NULL)
return NULL;
ret = gst_buffer_create_sub (map, offset - mapbase, size);
GST_BUFFER_OFFSET (ret) = GST_BUFFER_OFFSET (map) + offset - mapbase;
gst_buffer_unref (map);
} else {
ret = gst_file_src_map_region (src, offset, size, FALSE);
}
return ret;
}
static GstFlowReturn
gst_file_src_create_mmap (GstFileSrc * src, guint64 offset, guint length,
GstBuffer ** buffer)
{
GstBuffer *buf = NULL;
size_t readsize, mapsize;
off_t readend, mapstart, mapend;
int i;
/* calculate end pointers so we don't have to do so repeatedly later */
readsize = length;
readend = offset + readsize; /* note this is the byte *after* the read */
mapstart = GST_BUFFER_OFFSET (src->mapbuf);
mapsize = GST_BUFFER_SIZE (src->mapbuf);
mapend = mapstart + mapsize; /* note this is the byte *after* the map */
GST_LOG ("attempting to read %08lx, %08lx, %08lx, %08lx",
(unsigned long) readsize, (unsigned long) readend,
(unsigned long) mapstart, (unsigned long) mapend);
/* if the start is past the mapstart */
if (offset >= mapstart) {
/* if the end is before the mapend, the buffer is in current mmap region... */
/* ('cause by definition if readend is in the buffer, so's readstart) */
if (readend <= mapend) {
GST_LOG_OBJECT (src,
"read buf %llu+%d lives in current mapbuf %lld+%d, creating subbuffer of mapbuf",
offset, (int) readsize, mapstart, mapsize);
buf = gst_buffer_create_sub (src->mapbuf, offset - mapstart, readsize);
GST_BUFFER_OFFSET (buf) = offset;
/* if the start actually is within the current mmap region, map an overlap buffer */
} else if (offset < mapend) {
GST_LOG_OBJECT (src,
"read buf %llu+%d starts in mapbuf %d+%d but ends outside, creating new mmap",
(unsigned long long) offset, (gint) readsize, (gint) mapstart,
(gint) mapsize);
buf = gst_file_src_map_small_region (src, offset, readsize);
if (buf == NULL)
goto could_not_mmap;
}
/* the only other option is that buffer is totally outside, which means we search for it */
/* now we can assume that the start is *before* the current mmap region */
/* if the readend is past mapstart, we have two options */
} else if (readend >= mapstart) {
/* either the read buffer overlaps the start of the mmap region */
/* or the read buffer fully contains the current mmap region */
/* either way, it's really not relevant, we just create a new region anyway */
GST_LOG_OBJECT (src,
"read buf %llu+%d starts before mapbuf %d+%d, but overlaps it",
(unsigned long long) offset, (gint) readsize, (gint) mapstart,
(gint) mapsize);
buf = gst_file_src_map_small_region (src, offset, readsize);
if (buf == NULL)
goto could_not_mmap;
}
/* then deal with the case where the read buffer is totally outside */
if (buf == NULL) {
/* first check to see if there's a map that covers the right region already */
GST_LOG_OBJECT (src, "searching for mapbuf to cover %llu+%d",
offset, (int) readsize);
/* if the read buffer crosses a mmap region boundary, create a one-off region */
if ((offset / src->mapsize) != (readend / src->mapsize)) {
GST_LOG_OBJECT (src,
"read buf %llu+%d crosses a %d-byte boundary, creating a one-off",
offset, (int) readsize, (int) src->mapsize);
buf = gst_file_src_map_small_region (src, offset, readsize);
if (buf == NULL)
goto could_not_mmap;
/* otherwise we will create a new mmap region and set it to the default */
} else {
size_t mapsize;
off_t nextmap = offset - (offset % src->mapsize);
GST_LOG_OBJECT (src,
"read buf %llu+%d in new mapbuf at %llu+%d, mapping and subbuffering",
offset, readsize, nextmap, src->mapsize);
/* first, we're done with the old mapbuf */
gst_buffer_unref (src->mapbuf);
mapsize = src->mapsize;
/* double the mapsize as long as the readsize is smaller */
while (readsize + offset > nextmap + mapsize) {
GST_LOG_OBJECT (src, "readsize smaller then mapsize %08x %d",
readsize, (int) mapsize);
mapsize <<= 1;
}
/* create a new one */
src->mapbuf = gst_file_src_map_region (src, nextmap, mapsize, FALSE);
if (src->mapbuf == NULL)
goto could_not_mmap;
/* subbuffer it */
buf = gst_buffer_create_sub (src->mapbuf, offset - nextmap, readsize);
GST_BUFFER_OFFSET (buf) =
GST_BUFFER_OFFSET (src->mapbuf) + offset - nextmap;
}
}
/* if we need to touch the buffer (to bring it into memory), do so */
if (src->touch) {
volatile guchar *p = GST_BUFFER_DATA (buf), c;
/* read first byte of each page */
for (i = 0; i < GST_BUFFER_SIZE (buf); i += src->pagesize)
c = p[i];
}
/* we're done, return the buffer */
*buffer = buf;
return GST_FLOW_OK;
/* ERROR */
could_not_mmap:
{
return GST_FLOW_ERROR;
}
}
#endif
/***
* read code below
* that is to say, you shouldn't read the code below, but the code that reads
* stuff is below. Well, you shouldn't not read the code below, feel free
* to read it of course. It's just that "read code below" is a pretty crappy
* documentation string because it sounds like we're expecting you to read
* the code to understand what it does, which, while true, is really not
* the sort of attitude we want to be advertising. No sir.
*
*/
static GstFlowReturn
gst_file_src_create_read (GstFileSrc * src, guint64 offset, guint length,
GstBuffer ** buffer)
{
int ret;
GstBuffer *buf;
if (G_UNLIKELY (src->read_position != offset)) {
off_t res;
res = lseek (src->fd, offset, SEEK_SET);
if (G_UNLIKELY (res < 0 || res != offset))
goto seek_failed;
src->read_position = offset;
}
buf = gst_buffer_new_and_alloc (length);
GST_LOG_OBJECT (src, "Reading %d bytes", length);
ret = read (src->fd, GST_BUFFER_DATA (buf), length);
if (G_UNLIKELY (ret < 0))
goto could_not_read;
/* regular files should have given us what we expected */
if (G_UNLIKELY ((guint) ret < length && src->is_regular))
goto unexpected_eos;
/* other files should eos if they read 0 and more was requested */
if (G_UNLIKELY (ret == 0 && length > 0))
goto eos;
length = ret;
GST_BUFFER_SIZE (buf) = length;
GST_BUFFER_OFFSET (buf) = offset;
GST_BUFFER_OFFSET_END (buf) = offset + length;
*buffer = buf;
src->read_position += length;
return GST_FLOW_OK;
/* ERROR */
seek_failed:
{
GST_ELEMENT_ERROR (src, RESOURCE, READ, (NULL), GST_ERROR_SYSTEM);
return GST_FLOW_ERROR;
}
could_not_read:
{
GST_ELEMENT_ERROR (src, RESOURCE, READ, (NULL), GST_ERROR_SYSTEM);
gst_buffer_unref (buf);
return GST_FLOW_ERROR;
}
unexpected_eos:
{
GST_ELEMENT_ERROR (src, RESOURCE, READ, (NULL),
("unexpected end of file."));
gst_buffer_unref (buf);
return GST_FLOW_ERROR;
}
eos:
{
GST_DEBUG ("non-regular file hits EOS");
gst_buffer_unref (buf);
return GST_FLOW_UNEXPECTED;
}
}
static GstFlowReturn
gst_file_src_create (GstBaseSrc * basesrc, guint64 offset, guint length,
GstBuffer ** buffer)
{
GstFileSrc *src;
GstFlowReturn ret;
src = GST_FILE_SRC (basesrc);
#ifdef HAVE_MMAP
if (src->using_mmap) {
ret = gst_file_src_create_mmap (src, offset, length, buffer);
} else {
ret = gst_file_src_create_read (src, offset, length, buffer);
}
#else
ret = gst_file_src_create_read (src, offset, length, buffer);
#endif
return ret;
}
static gboolean
gst_file_src_is_seekable (GstBaseSrc * basesrc)
{
GstFileSrc *src = GST_FILE_SRC (basesrc);
return src->seekable;
}
static gboolean
gst_file_src_get_size (GstBaseSrc * basesrc, guint64 * size)
{
struct stat stat_results;
GstFileSrc *src;
src = GST_FILE_SRC (basesrc);
if (!src->seekable) {
/* If it isn't seekable, we won't know the length (but fstat will still
* succeed, and wrongly say our length is zero. */
return FALSE;
}
if (fstat (src->fd, &stat_results) < 0)
goto could_not_stat;
*size = stat_results.st_size;
return TRUE;
/* ERROR */
could_not_stat:
{
return FALSE;
}
}
/* open the file and mmap it, necessary to go to READY state */
static gboolean
gst_file_src_start (GstBaseSrc * basesrc)
{
GstFileSrc *src = GST_FILE_SRC (basesrc);
struct stat stat_results;
if (src->filename == NULL || src->filename[0] == '\0')
goto no_filename;
GST_INFO_OBJECT (src, "opening file %s", src->filename);
/* open the file */
src->fd = open (src->filename, O_RDONLY | O_BINARY);
if (src->fd < 0)
goto open_failed;
/* check if it is a regular file, otherwise bail out */
if (fstat (src->fd, &stat_results) < 0)
goto no_stat;
if (S_ISDIR (stat_results.st_mode))
goto was_directory;
if (S_ISSOCK (stat_results.st_mode))
goto was_socket;
src->using_mmap = FALSE;
src->read_position = 0;
/* record if it's a regular (hence seekable and lengthable) file */
if (S_ISREG (stat_results.st_mode))
src->is_regular = TRUE;
#ifdef HAVE_MMAP
if (src->use_mmap) {
/* FIXME: maybe we should only try to mmap if it's a regular file */
/* allocate the first mmap'd region if it's a regular file ? */
src->mapbuf = gst_file_src_map_region (src, 0, src->mapsize, TRUE);
if (src->mapbuf != NULL) {
GST_DEBUG_OBJECT (src, "using mmap for file");
src->using_mmap = TRUE;
src->seekable = TRUE;
}
}
if (src->mapbuf == NULL)
#endif
{
/* If not in mmap mode, we need to check if the underlying file is
* seekable. */
off_t res = lseek (src->fd, 0, SEEK_CUR);
if (res < 0) {
GST_LOG_OBJECT (src, "disabling seeking, not in mmap mode and lseek "
"failed: %s", strerror (errno));
src->seekable = FALSE;
} else {
src->seekable = TRUE;
}
}
/* We can only really do seeking on regular files - for other file types, we
* don't know their length, so seeking isn't useful/meaningful */
src->seekable = src->seekable && src->is_regular;
return TRUE;
/* ERROR */
no_filename:
{
GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND,
(_("No file name specified for reading.")), (NULL));
return FALSE;
}
open_failed:
{
switch (errno) {
case ENOENT:
GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND, (NULL),
("No such file \"%s\"", src->filename));
break;
default:
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("Could not open file \"%s\" for reading: %s."), src->filename,
strerror (errno)), GST_ERROR_SYSTEM);
break;
}
return FALSE;
}
no_stat:
{
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("Could not get info on \"%s\"."), src->filename), (NULL));
close (src->fd);
return FALSE;
}
was_directory:
{
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("\"%s\" is a directory."), src->filename), (NULL));
close (src->fd);
return FALSE;
}
was_socket:
{
GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ,
(_("File \"%s\" is a socket."), src->filename), (NULL));
close (src->fd);
return FALSE;
}
}
/* unmap and close the file */
static gboolean
gst_file_src_stop (GstBaseSrc * basesrc)
{
GstFileSrc *src = GST_FILE_SRC (basesrc);
/* close the file */
close (src->fd);
/* zero out a lot of our state */
src->fd = 0;
src->is_regular = FALSE;
if (src->mapbuf) {
gst_buffer_unref (src->mapbuf);
src->mapbuf = NULL;
}
return TRUE;
}
/*** GSTURIHANDLER INTERFACE *************************************************/
static guint
gst_file_src_uri_get_type (void)
{
return GST_URI_SRC;
}
static gchar **
gst_file_src_uri_get_protocols (void)
{
static gchar *protocols[] = { "file", NULL };
return protocols;
}
static const gchar *
gst_file_src_uri_get_uri (GstURIHandler * handler)
{
GstFileSrc *src = GST_FILE_SRC (handler);
return src->uri;
}
static gboolean
gst_file_src_uri_set_uri (GstURIHandler * handler, const gchar * uri)
{
gchar *protocol, *location;
gboolean ret;
GstFileSrc *src = GST_FILE_SRC (handler);
protocol = gst_uri_get_protocol (uri);
if (strcmp (protocol, "file") != 0) {
g_free (protocol);
return FALSE;
}
g_free (protocol);
location = gst_uri_get_location (uri);
ret = gst_file_src_set_location (src, location);
g_free (location);
return ret;
}
static void
gst_file_src_uri_handler_init (gpointer g_iface, gpointer iface_data)
{
GstURIHandlerInterface *iface = (GstURIHandlerInterface *) g_iface;
iface->get_type = gst_file_src_uri_get_type;
iface->get_protocols = gst_file_src_uri_get_protocols;
iface->get_uri = gst_file_src_uri_get_uri;
iface->set_uri = gst_file_src_uri_set_uri;
}