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gstreamer/gst/gststructure.c

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/* GStreamer
* Copyright (C) 2003 David A. Schleef <ds@schleef.org>
*
* gststructure.c: lists of { GQuark, GValue } tuples
*
* 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:gststructure
* @short_description: Generic structure containing fields of names and values
* @see_also: #GstCaps, #GstMessage, #GstEvent, #GstQuery
*
* A #GstStructure is a collection of key/value pairs. The keys are expressed
* as GQuarks and the values can be of any GType.
*
* In addition to the key/value pairs, a #GstStructure also has a name. The name
* starts with a letter and can be folled by letters, numbers and any of "/-_.:".
*
* #GstStructure is used by various GStreamer subsystems to store information
* in a flexible and extensible way. A #GstStructure does not have a refcount
* because it usually is part of a higher level object such as #GstCaps. It
* provides a means to enforce mutability using the refcount of the parent
* with the gst_structure_set_parent_refcount() method.
*
* A #GstStructure can be created with gst_structure_empty_new() or
* gst_structure_new(), which both take a name and an optional set of
* key/value pairs along with the types of the values.
*
* Field values can be changed with gst_structure_set_value() or
* gst_structure_set().
*
* Field values can be retrieved with gst_structure_get_value() or the more
* convenient gst_structure_get_*() functions.
*
* Fields can be removed with gst_structure_remove_field() or
* gst_structure_remove_fields().
*
* Strings in structures must be ASCII or UTF-8 encoded. Other encodings are
* not allowed. Strings must not be empty either, but may be NULL.
*
* Last reviewed on 2009-06-08 (0.10.23)
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "gst_private.h"
#include "gstquark.h"
#include <gst/gst.h>
#include <gobject/gvaluecollector.h>
typedef struct _GstStructureField GstStructureField;
struct _GstStructureField
{
GQuark name;
GValue value;
};
#define GST_STRUCTURE_FIELD(structure, index) \
&g_array_index((structure)->fields, GstStructureField, (index))
#define IS_MUTABLE(structure) \
(!(structure)->parent_refcount || \
g_atomic_int_get ((structure)->parent_refcount) == 1)
#define IS_TAGLIST(structure) \
(structure->name == GST_QUARK (TAGLIST))
static void gst_structure_set_field (GstStructure * structure,
GstStructureField * field);
static GstStructureField *gst_structure_get_field (const GstStructure *
structure, const gchar * fieldname);
static GstStructureField *gst_structure_id_get_field (const GstStructure *
structure, GQuark field);
static void gst_structure_transform_to_string (const GValue * src_value,
GValue * dest_value);
static GstStructure *gst_structure_copy_conditional (const GstStructure *
structure);
static gboolean gst_structure_parse_value (gchar * str, gchar ** after,
GValue * value, GType default_type);
static gboolean gst_structure_parse_simple_string (gchar * s, gchar ** end);
GType
gst_structure_get_type (void)
{
static GType gst_structure_type = 0;
if (G_UNLIKELY (gst_structure_type == 0)) {
gst_structure_type = g_boxed_type_register_static ("GstStructure",
(GBoxedCopyFunc) gst_structure_copy_conditional,
(GBoxedFreeFunc) gst_structure_free);
g_value_register_transform_func (gst_structure_type, G_TYPE_STRING,
gst_structure_transform_to_string);
}
return gst_structure_type;
}
static GstStructure *
gst_structure_id_empty_new_with_size (GQuark quark, guint prealloc)
{
GstStructure *structure;
structure = g_slice_new (GstStructure);
structure->type = gst_structure_get_type ();
structure->name = quark;
structure->parent_refcount = NULL;
structure->fields =
g_array_sized_new (FALSE, FALSE, sizeof (GstStructureField), prealloc);
return structure;
}
/**
* gst_structure_id_empty_new:
* @quark: name of new structure
*
* Creates a new, empty #GstStructure with the given name as a GQuark.
*
* Returns: a new, empty #GstStructure
*/
GstStructure *
gst_structure_id_empty_new (GQuark quark)
{
g_return_val_if_fail (quark != 0, NULL);
return gst_structure_id_empty_new_with_size (quark, 0);
}
#ifndef G_DISABLE_CHECKS
static gboolean
gst_structure_validate_name (const gchar * name)
{
const gchar *s;
g_return_val_if_fail (name != NULL, FALSE);
/* FIXME 0.11: use g_ascii_isalpha() */
if (!g_ascii_isalnum (*name)) {
GST_WARNING ("Invalid character '%c' at offset 0 in structure name: %s",
*name, name);
return FALSE;
}
/* FIXME 0.11: don't allow spaces */
/* FIXME: test name string more */
s = &name[1];
while (*s && (g_ascii_isalnum (*s) || strchr ("/-_.:+ ", *s) != NULL))
s++;
if (*s != '\0') {
GST_WARNING ("Invalid character '%c' at offset %lu in structure name: %s",
*s, ((gulong) s - (gulong) name), name);
return FALSE;
}
return TRUE;
}
#endif
/**
* gst_structure_empty_new:
* @name: name of new structure
*
* Creates a new, empty #GstStructure with the given @name.
*
* See gst_structure_set_name() for constraints on the @name parameter.
*
* Returns: a new, empty #GstStructure
*/
GstStructure *
gst_structure_empty_new (const gchar * name)
{
g_return_val_if_fail (gst_structure_validate_name (name), NULL);
return gst_structure_id_empty_new_with_size (g_quark_from_string (name), 0);
}
/**
* gst_structure_new:
* @name: name of new structure
* @firstfield: name of first field to set
* @...: additional arguments
*
* Creates a new #GstStructure with the given name. Parses the
* list of variable arguments and sets fields to the values listed.
* Variable arguments should be passed as field name, field type,
* and value. Last variable argument should be NULL.
*
* Returns: a new #GstStructure
*/
GstStructure *
gst_structure_new (const gchar * name, const gchar * firstfield, ...)
{
GstStructure *structure;
va_list varargs;
g_return_val_if_fail (name != NULL, NULL);
va_start (varargs, firstfield);
structure = gst_structure_new_valist (name, firstfield, varargs);
va_end (varargs);
return structure;
}
/**
* gst_structure_new_valist:
* @name: name of new structure
* @firstfield: name of first field to set
* @varargs: variable argument list
*
* Creates a new #GstStructure with the given @name. Structure fields
* are set according to the varargs in a manner similar to
* gst_structure_new().
*
* See gst_structure_set_name() for constraints on the @name parameter.
*
* Returns: a new #GstStructure
*/
GstStructure *
gst_structure_new_valist (const gchar * name,
const gchar * firstfield, va_list varargs)
{
GstStructure *structure;
g_return_val_if_fail (name != NULL, NULL);
structure = gst_structure_empty_new (name);
if (structure)
gst_structure_set_valist (structure, firstfield, varargs);
return structure;
}
/**
* gst_structure_set_parent_refcount:
* @structure: a #GstStructure
* @refcount: a pointer to the parent's refcount
*
* Sets the parent_refcount field of #GstStructure. This field is used to
* determine whether a structure is mutable or not. This function should only be
* called by code implementing parent objects of #GstStructure, as described in
* the MT Refcounting section of the design documents.
*/
void
gst_structure_set_parent_refcount (GstStructure * structure, int *refcount)
{
g_return_if_fail (structure != NULL);
/* if we have a parent_refcount already, we can only clear
* if with a NULL refcount */
if (structure->parent_refcount)
g_return_if_fail (refcount == NULL);
else
g_return_if_fail (refcount != NULL);
structure->parent_refcount = refcount;
}
/**
* gst_structure_copy:
* @structure: a #GstStructure to duplicate
*
* Duplicates a #GstStructure and all its fields and values.
*
* Returns: a new #GstStructure.
*/
GstStructure *
gst_structure_copy (const GstStructure * structure)
{
GstStructure *new_structure;
GstStructureField *field;
guint i, len;
g_return_val_if_fail (structure != NULL, NULL);
new_structure =
gst_structure_id_empty_new_with_size (structure->name,
structure->fields->len);
len = structure->fields->len;
for (i = 0; i < len; i++) {
GstStructureField new_field = { 0 };
field = GST_STRUCTURE_FIELD (structure, i);
new_field.name = field->name;
gst_value_init_and_copy (&new_field.value, &field->value);
g_array_append_val (new_structure->fields, new_field);
}
return new_structure;
}
/**
* gst_structure_free:
* @structure: the #GstStructure to free
*
* Frees a #GstStructure and all its fields and values. The structure must not
* have a parent when this function is called.
*/
void
gst_structure_free (GstStructure * structure)
{
GstStructureField *field;
guint i, len;
g_return_if_fail (structure != NULL);
g_return_if_fail (structure->parent_refcount == NULL);
len = structure->fields->len;
for (i = 0; i < len; i++) {
field = GST_STRUCTURE_FIELD (structure, i);
if (G_IS_VALUE (&field->value)) {
g_value_unset (&field->value);
}
}
g_array_free (structure->fields, TRUE);
#ifdef USE_POISONING
memset (structure, 0xff, sizeof (GstStructure));
#endif
g_slice_free (GstStructure, structure);
}
/**
* gst_structure_get_name:
* @structure: a #GstStructure
*
* Get the name of @structure as a string.
*
* Returns: the name of the structure.
*/
const gchar *
gst_structure_get_name (const GstStructure * structure)
{
g_return_val_if_fail (structure != NULL, NULL);
return g_quark_to_string (structure->name);
}
/**
* gst_structure_has_name:
* @structure: a #GstStructure
* @name: structure name to check for
*
* Checks if the structure has the given name
*
* Returns: TRUE if @name matches the name of the structure.
*/
gboolean
gst_structure_has_name (const GstStructure * structure, const gchar * name)
{
const gchar *structure_name;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (name != NULL, FALSE);
/* getting the string is cheap and comparing short strings is too
* should be faster than getting the quark for name and comparing the quarks
*/
structure_name = g_quark_to_string (structure->name);
return (structure_name && strcmp (structure_name, name) == 0);
}
/**
* gst_structure_get_name_id:
* @structure: a #GstStructure
*
* Get the name of @structure as a GQuark.
*
* Returns: the quark representing the name of the structure.
*/
GQuark
gst_structure_get_name_id (const GstStructure * structure)
{
g_return_val_if_fail (structure != NULL, 0);
return structure->name;
}
/**
* gst_structure_set_name:
* @structure: a #GstStructure
* @name: the new name of the structure
*
* Sets the name of the structure to the given @name. The string
* provided is copied before being used. It must not be empty, start with a
* letter and can be followed by letters, numbers and any of "/-_.:".
*/
void
gst_structure_set_name (GstStructure * structure, const gchar * name)
{
g_return_if_fail (structure != NULL);
g_return_if_fail (IS_MUTABLE (structure));
g_return_if_fail (gst_structure_validate_name (name));
structure->name = g_quark_from_string (name);
}
/**
* gst_structure_id_set_value:
* @structure: a #GstStructure
* @field: a #GQuark representing a field
* @value: the new value of the field
*
* Sets the field with the given GQuark @field to @value. If the field
* does not exist, it is created. If the field exists, the previous
* value is replaced and freed.
*/
void
gst_structure_id_set_value (GstStructure * structure,
GQuark field, const GValue * value)
{
GstStructureField gsfield = { 0, {0,} };
g_return_if_fail (structure != NULL);
g_return_if_fail (G_IS_VALUE (value));
g_return_if_fail (IS_MUTABLE (structure));
gsfield.name = field;
gst_value_init_and_copy (&gsfield.value, value);
gst_structure_set_field (structure, &gsfield);
}
/**
* gst_structure_set_value:
* @structure: a #GstStructure
* @fieldname: the name of the field to set
* @value: the new value of the field
*
* Sets the field with the given name @field to @value. If the field
* does not exist, it is created. If the field exists, the previous
* value is replaced and freed.
*/
void
gst_structure_set_value (GstStructure * structure,
const gchar * fieldname, const GValue * value)
{
g_return_if_fail (structure != NULL);
g_return_if_fail (fieldname != NULL);
g_return_if_fail (G_IS_VALUE (value));
g_return_if_fail (IS_MUTABLE (structure));
gst_structure_id_set_value (structure, g_quark_from_string (fieldname),
value);
}
/**
* gst_structure_set:
* @structure: a #GstStructure
* @fieldname: the name of the field to set
* @...: variable arguments
*
* Parses the variable arguments and sets fields accordingly.
* Variable arguments should be in the form field name, field type
* (as a GType), value(s). The last variable argument should be NULL.
*/
void
gst_structure_set (GstStructure * structure, const gchar * field, ...)
{
va_list varargs;
g_return_if_fail (structure != NULL);
va_start (varargs, field);
gst_structure_set_valist (structure, field, varargs);
va_end (varargs);
}
/**
* gst_structure_set_valist:
* @structure: a #GstStructure
* @fieldname: the name of the field to set
* @varargs: variable arguments
*
* va_list form of gst_structure_set().
*/
void
gst_structure_set_valist (GstStructure * structure,
const gchar * fieldname, va_list varargs)
{
gchar *err = NULL;
GType type;
g_return_if_fail (structure != NULL);
g_return_if_fail (IS_MUTABLE (structure));
while (fieldname) {
GstStructureField field = { 0 };
field.name = g_quark_from_string (fieldname);
type = va_arg (varargs, GType);
if (type == G_TYPE_DATE) {
g_warning ("Don't use G_TYPE_DATE, use GST_TYPE_DATE instead\n");
type = GST_TYPE_DATE;
}
g_value_init (&field.value, type);
G_VALUE_COLLECT (&field.value, varargs, 0, &err);
if (err) {
g_critical ("%s", err);
return;
}
gst_structure_set_field (structure, &field);
fieldname = va_arg (varargs, gchar *);
}
}
/**
* gst_structure_id_set:
* @structure: a #GstStructure
* @fieldname: the GQuark for the name of the field to set
* @...: variable arguments
*
* Identical to gst_structure_set, except that field names are
* passed using the GQuark for the field name. This allows more efficient
* setting of the structure if the caller already knows the associated
* quark values.
* The last variable argument must be NULL.
*
* Since: 0.10.10
*/
void
gst_structure_id_set (GstStructure * structure, GQuark field, ...)
{
va_list varargs;
g_return_if_fail (structure != NULL);
va_start (varargs, field);
gst_structure_id_set_valist (structure, field, varargs);
va_end (varargs);
}
/**
* gst_structure_id_set_valist:
* @structure: a #GstStructure
* @fieldname: the name of the field to set
* @varargs: variable arguments
*
* va_list form of gst_structure_id_set().
*
* Since: 0.10.10
*/
void
gst_structure_id_set_valist (GstStructure * structure,
GQuark fieldname, va_list varargs)
{
gchar *err = NULL;
GType type;
g_return_if_fail (structure != NULL);
g_return_if_fail (IS_MUTABLE (structure));
while (fieldname) {
GstStructureField field = { 0 };
field.name = fieldname;
type = va_arg (varargs, GType);
if (type == G_TYPE_DATE) {
g_warning ("Don't use G_TYPE_DATE, use GST_TYPE_DATE instead\n");
type = GST_TYPE_DATE;
}
g_value_init (&field.value, type);
G_VALUE_COLLECT (&field.value, varargs, 0, &err);
if (err) {
g_critical ("%s", err);
return;
}
gst_structure_set_field (structure, &field);
fieldname = va_arg (varargs, GQuark);
}
}
/**
* gst_structure_id_new:
* @name_quark: name of new structure
* @field_quark: the GQuark for the name of the field to set
* @...: variable arguments
*
* Creates a new #GstStructure with the given name as a GQuark, followed by
* fieldname quark, GType, argument(s) "triplets" in the same format as
* gst_structure_id_set(). Basically a convenience wrapper around
* gst_structure_id_empty_new() and gst_structure_id_set().
*
* The last variable argument must be NULL (or 0).
*
* Returns: a new #GstStructure
*
* Since: 0.10.24
*/
GstStructure *
gst_structure_id_new (GQuark name_quark, GQuark field_quark, ...)
{
GstStructure *s;
va_list varargs;
g_return_val_if_fail (name_quark != 0, NULL);
g_return_val_if_fail (field_quark != 0, NULL);
s = gst_structure_id_empty_new (name_quark);
va_start (varargs, field_quark);
gst_structure_id_set_valist (s, field_quark, varargs);
va_end (varargs);
return s;
}
/* If the structure currently contains a field with the same name, it is
* replaced with the provided field. Otherwise, the field is added to the
* structure. The field's value is not deeply copied.
*/
static void
gst_structure_set_field (GstStructure * structure, GstStructureField * field)
{
GstStructureField *f;
guint i, len = structure->fields->len;
if (G_UNLIKELY (G_VALUE_HOLDS_STRING (&field->value))) {
const gchar *s;
s = g_value_get_string (&field->value);
/* only check for NULL strings in taglists, as they are allowed in message
* structs, e.g. error message debug strings */
if (G_UNLIKELY (s == NULL && IS_TAGLIST (structure))) {
g_warning ("Trying to set NULL string on field '%s' on taglist. "
"Please file a bug.", g_quark_to_string (field->name));
g_value_unset (&field->value);
return;
} else if (G_UNLIKELY (s != NULL && *s == '\0')) {
/* empty strings never make sense */
g_warning ("Trying to set empty string on %s field '%s'. Please file a "
"bug.", IS_TAGLIST (structure) ? "taglist" : "structure",
g_quark_to_string (field->name));
g_value_unset (&field->value);
return;
} else if (G_UNLIKELY (s != NULL && !g_utf8_validate (s, -1, NULL))) {
g_warning ("Trying to set string on %s field '%s', but string is not "
"valid UTF-8. Please file a bug.",
IS_TAGLIST (structure) ? "taglist" : "structure",
g_quark_to_string (field->name));
g_value_unset (&field->value);
return;
}
}
for (i = 0; i < len; i++) {
f = GST_STRUCTURE_FIELD (structure, i);
if (f->name == field->name) {
g_value_unset (&f->value);
memcpy (f, field, sizeof (GstStructureField));
return;
}
}
g_array_append_val (structure->fields, *field);
}
/* If there is no field with the given ID, NULL is returned.
*/
static GstStructureField *
gst_structure_id_get_field (const GstStructure * structure, GQuark field_id)
{
GstStructureField *field;
guint i, len;
len = structure->fields->len;
g_return_val_if_fail (structure != NULL, NULL);
for (i = 0; i < len; i++) {
field = GST_STRUCTURE_FIELD (structure, i);
if (field->name == field_id)
return field;
}
return NULL;
}
/* If there is no field with the given ID, NULL is returned.
*/
static GstStructureField *
gst_structure_get_field (const GstStructure * structure,
const gchar * fieldname)
{
g_return_val_if_fail (structure != NULL, NULL);
g_return_val_if_fail (fieldname != NULL, NULL);
return gst_structure_id_get_field (structure,
g_quark_from_string (fieldname));
}
/**
* gst_structure_get_value:
* @structure: a #GstStructure
* @fieldname: the name of the field to get
*
* Get the value of the field with name @fieldname.
*
* Returns: the #GValue corresponding to the field with the given name.
*/
const GValue *
gst_structure_get_value (const GstStructure * structure,
const gchar * fieldname)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, NULL);
g_return_val_if_fail (fieldname != NULL, NULL);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return NULL;
return &field->value;
}
/**
* gst_structure_id_get_value:
* @structure: a #GstStructure
* @field: the #GQuark of the field to get
*
* Get the value of the field with GQuark @field.
*
* Returns: the #GValue corresponding to the field with the given name
* identifier.
*/
const GValue *
gst_structure_id_get_value (const GstStructure * structure, GQuark field)
{
GstStructureField *gsfield;
g_return_val_if_fail (structure != NULL, NULL);
gsfield = gst_structure_id_get_field (structure, field);
if (gsfield == NULL)
return NULL;
return &gsfield->value;
}
/**
* gst_structure_remove_field:
* @structure: a #GstStructure
* @fieldname: the name of the field to remove
*
* Removes the field with the given name. If the field with the given
* name does not exist, the structure is unchanged.
*/
void
gst_structure_remove_field (GstStructure * structure, const gchar * fieldname)
{
GstStructureField *field;
GQuark id;
guint i, len;
g_return_if_fail (structure != NULL);
g_return_if_fail (fieldname != NULL);
g_return_if_fail (IS_MUTABLE (structure));
id = g_quark_from_string (fieldname);
len = structure->fields->len;
for (i = 0; i < len; i++) {
field = GST_STRUCTURE_FIELD (structure, i);
if (field->name == id) {
if (G_IS_VALUE (&field->value)) {
g_value_unset (&field->value);
}
structure->fields = g_array_remove_index (structure->fields, i);
return;
}
}
}
/**
* gst_structure_remove_fields:
* @structure: a #GstStructure
* @fieldname: the name of the field to remove
* @...: NULL-terminated list of more fieldnames to remove
*
* Removes the fields with the given names. If a field does not exist, the
* argument is ignored.
*/
void
gst_structure_remove_fields (GstStructure * structure,
const gchar * fieldname, ...)
{
va_list varargs;
g_return_if_fail (structure != NULL);
g_return_if_fail (fieldname != NULL);
/* mutability checked in remove_field */
va_start (varargs, fieldname);
gst_structure_remove_fields_valist (structure, fieldname, varargs);
va_end (varargs);
}
/**
* gst_structure_remove_fields_valist:
* @structure: a #GstStructure
* @fieldname: the name of the field to remove
* @varargs: NULL-terminated list of more fieldnames to remove
*
* va_list form of gst_structure_remove_fields().
*/
void
gst_structure_remove_fields_valist (GstStructure * structure,
const gchar * fieldname, va_list varargs)
{
gchar *field = (gchar *) fieldname;
g_return_if_fail (structure != NULL);
g_return_if_fail (fieldname != NULL);
/* mutability checked in remove_field */
while (field) {
gst_structure_remove_field (structure, field);
field = va_arg (varargs, char *);
}
}
/**
* gst_structure_remove_all_fields:
* @structure: a #GstStructure
*
* Removes all fields in a GstStructure.
*/
void
gst_structure_remove_all_fields (GstStructure * structure)
{
GstStructureField *field;
int i;
g_return_if_fail (structure != NULL);
g_return_if_fail (IS_MUTABLE (structure));
for (i = structure->fields->len - 1; i >= 0; i--) {
field = GST_STRUCTURE_FIELD (structure, i);
if (G_IS_VALUE (&field->value)) {
g_value_unset (&field->value);
}
structure->fields = g_array_remove_index (structure->fields, i);
}
}
/**
* gst_structure_get_field_type:
* @structure: a #GstStructure
* @fieldname: the name of the field
*
* Finds the field with the given name, and returns the type of the
* value it contains. If the field is not found, G_TYPE_INVALID is
* returned.
*
* Returns: the #GValue of the field
*/
GType
gst_structure_get_field_type (const GstStructure * structure,
const gchar * fieldname)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, G_TYPE_INVALID);
g_return_val_if_fail (fieldname != NULL, G_TYPE_INVALID);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return G_TYPE_INVALID;
return G_VALUE_TYPE (&field->value);
}
/**
* gst_structure_n_fields:
* @structure: a #GstStructure
*
* Get the number of fields in the structure.
*
* Returns: the number of fields in the structure
*/
gint
gst_structure_n_fields (const GstStructure * structure)
{
g_return_val_if_fail (structure != NULL, 0);
return structure->fields->len;
}
/**
* gst_structure_nth_field_name:
* @structure: a #GstStructure
* @index: the index to get the name of
*
* Get the name of the given field number, counting from 0 onwards.
*
* Returns: the name of the given field number
*/
const gchar *
gst_structure_nth_field_name (const GstStructure * structure, guint index)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, NULL);
g_return_val_if_fail (index < structure->fields->len, NULL);
field = GST_STRUCTURE_FIELD (structure, index);
return g_quark_to_string (field->name);
}
/**
* gst_structure_foreach:
* @structure: a #GstStructure
* @func: a function to call for each field
* @user_data: private data
*
* Calls the provided function once for each field in the #GstStructure. The
* function must not modify the fields. Also see gst_structure_map_in_place().
*
* Returns: TRUE if the supplied function returns TRUE For each of the fields,
* FALSE otherwise.
*/
gboolean
gst_structure_foreach (const GstStructure * structure,
GstStructureForeachFunc func, gpointer user_data)
{
guint i, len;
GstStructureField *field;
gboolean ret;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (func != NULL, FALSE);
len = structure->fields->len;
for (i = 0; i < len; i++) {
field = GST_STRUCTURE_FIELD (structure, i);
ret = func (field->name, &field->value, user_data);
if (!ret)
return FALSE;
}
return TRUE;
}
/**
* gst_structure_map_in_place:
* @structure: a #GstStructure
* @func: a function to call for each field
* @user_data: private data
*
* Calls the provided function once for each field in the #GstStructure. In
* contrast to gst_structure_foreach(), the function may modify but not delete the
* fields. The structure must be mutable.
*
* Returns: TRUE if the supplied function returns TRUE For each of the fields,
* FALSE otherwise.
*/
gboolean
gst_structure_map_in_place (GstStructure * structure,
GstStructureMapFunc func, gpointer user_data)
{
guint i, len;
GstStructureField *field;
gboolean ret;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (IS_MUTABLE (structure), FALSE);
g_return_val_if_fail (func != NULL, FALSE);
len = structure->fields->len;
for (i = 0; i < len; i++) {
field = GST_STRUCTURE_FIELD (structure, i);
ret = func (field->name, &field->value, user_data);
if (!ret)
return FALSE;
}
return TRUE;
}
/**
* gst_structure_has_field:
* @structure: a #GstStructure
* @fieldname: the name of a field
*
* Check if @structure contains a field named @fieldname.
*
* Returns: TRUE if the structure contains a field with the given name
*/
gboolean
gst_structure_has_field (const GstStructure * structure,
const gchar * fieldname)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, 0);
g_return_val_if_fail (fieldname != NULL, 0);
field = gst_structure_get_field (structure, fieldname);
return (field != NULL);
}
/**
* gst_structure_has_field_typed:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @type: the type of a value
*
* Check if @structure contains a field named @fieldname and with GType @type.
*
* Returns: TRUE if the structure contains a field with the given name and type
*/
gboolean
gst_structure_has_field_typed (const GstStructure * structure,
const gchar * fieldname, GType type)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, 0);
g_return_val_if_fail (fieldname != NULL, 0);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
return (G_VALUE_TYPE (&field->value) == type);
}
/* utility functions */
/**
* gst_structure_get_boolean:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value: a pointer to a #gboolean to set
*
* Sets the boolean pointed to by @value corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain a boolean, this
* function returns FALSE.
*/
gboolean
gst_structure_get_boolean (const GstStructure * structure,
const gchar * fieldname, gboolean * value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!G_VALUE_HOLDS_BOOLEAN (&field->value))
return FALSE;
*value = g_value_get_boolean (&field->value);
return TRUE;
}
/**
* gst_structure_get_int:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value: a pointer to an int to set
*
* Sets the int pointed to by @value corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: %TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain an int, this function
* returns %FALSE.
*/
gboolean
gst_structure_get_int (const GstStructure * structure,
const gchar * fieldname, gint * value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!G_VALUE_HOLDS_INT (&field->value))
return FALSE;
*value = g_value_get_int (&field->value);
return TRUE;
}
/**
* gst_structure_get_uint:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value: a pointer to a uint to set
*
* Sets the uint pointed to by @value corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: %TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain a uint, this function
* returns %FALSE.
*
* Since: 0.10.15
*/
gboolean
gst_structure_get_uint (const GstStructure * structure,
const gchar * fieldname, guint * value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!G_VALUE_HOLDS_UINT (&field->value))
return FALSE;
*value = g_value_get_uint (&field->value);
return TRUE;
}
/**
* gst_structure_get_fourcc:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value: a pointer to a #GstFourcc to set
*
* Sets the #GstFourcc pointed to by @value corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain a fourcc, this function
* returns FALSE.
*/
gboolean
gst_structure_get_fourcc (const GstStructure * structure,
const gchar * fieldname, guint32 * value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!GST_VALUE_HOLDS_FOURCC (&field->value))
return FALSE;
*value = gst_value_get_fourcc (&field->value);
return TRUE;
}
/**
* gst_structure_get_date:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value: a pointer to a #GDate to set
*
* Sets the date pointed to by @value corresponding to the date of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* On success @value will point to a newly-allocated copy of the date which
* should be freed with g_date_free() when no longer needed (note: this is
* inconsistent with e.g. gst_structure_get_string() which doesn't return a
* copy of the string).
*
* Returns: TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain a data, this function
* returns FALSE.
*/
gboolean
gst_structure_get_date (const GstStructure * structure, const gchar * fieldname,
GDate ** value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!GST_VALUE_HOLDS_DATE (&field->value))
return FALSE;
/* FIXME: 0.11 g_value_dup_boxed() -> g_value_get_boxed() */
*value = g_value_dup_boxed (&field->value);
return TRUE;
}
/**
* gst_structure_get_clock_time:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value: a pointer to a #GstClockTime to set
*
* Sets the clock time pointed to by @value corresponding to the clock time
* of the given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain a #GstClockTime, this
* function returns FALSE.
*/
gboolean
gst_structure_get_clock_time (const GstStructure * structure,
const gchar * fieldname, GstClockTime * value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!G_VALUE_HOLDS_UINT64 (&field->value))
return FALSE;
*value = g_value_get_uint64 (&field->value);
return TRUE;
}
/**
* gst_structure_get_double:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value: a pointer to a #GstFourcc to set
*
* Sets the double pointed to by @value corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain a double, this
* function returns FALSE.
*/
gboolean
gst_structure_get_double (const GstStructure * structure,
const gchar * fieldname, gdouble * value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!G_VALUE_HOLDS_DOUBLE (&field->value))
return FALSE;
*value = g_value_get_double (&field->value);
return TRUE;
}
/**
* gst_structure_get_string:
* @structure: a #GstStructure
* @fieldname: the name of a field
*
* Finds the field corresponding to @fieldname, and returns the string
* contained in the field's value. Caller is responsible for making
* sure the field exists and has the correct type.
*
* The string should not be modified, and remains valid until the next
* call to a gst_structure_*() function with the given structure.
*
* Returns: a pointer to the string or NULL when the field did not exist
* or did not contain a string.
*/
const gchar *
gst_structure_get_string (const GstStructure * structure,
const gchar * fieldname)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, NULL);
g_return_val_if_fail (fieldname != NULL, NULL);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return NULL;
if (!G_VALUE_HOLDS_STRING (&field->value))
return NULL;
return g_value_get_string (&field->value);
}
/**
* gst_structure_get_enum:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @enumtype: the enum type of a field
* @value: a pointer to an int to set
*
* Sets the int pointed to by @value corresponding to the value of the
* given field. Caller is responsible for making sure the field exists,
* has the correct type and that the enumtype is correct.
*
* Returns: TRUE if the value could be set correctly. If there was no field
* with @fieldname or the existing field did not contain an enum of the given
* type, this function returns FALSE.
*/
gboolean
gst_structure_get_enum (const GstStructure * structure,
const gchar * fieldname, GType enumtype, gint * value)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (enumtype != G_TYPE_INVALID, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!G_VALUE_HOLDS_ENUM (&field->value))
return FALSE;
if (!G_TYPE_CHECK_VALUE_TYPE (&field->value, enumtype))
return FALSE;
*value = g_value_get_enum (&field->value);
return TRUE;
}
/**
* gst_structure_get_fraction:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @value_numerator: a pointer to an int to set
* @value_denominator: a pointer to an int to set
*
* Sets the integers pointed to by @value_numerator and @value_denominator
* corresponding to the value of the given field. Caller is responsible
* for making sure the field exists and has the correct type.
*
* Returns: TRUE if the values could be set correctly. If there was no field
* with @fieldname or the existing field did not contain a GstFraction, this
* function returns FALSE.
*/
gboolean
gst_structure_get_fraction (const GstStructure * structure,
const gchar * fieldname, gint * value_numerator, gint * value_denominator)
{
GstStructureField *field;
g_return_val_if_fail (structure != NULL, FALSE);
g_return_val_if_fail (fieldname != NULL, FALSE);
g_return_val_if_fail (value_numerator != NULL, FALSE);
g_return_val_if_fail (value_denominator != NULL, FALSE);
field = gst_structure_get_field (structure, fieldname);
if (field == NULL)
return FALSE;
if (!GST_VALUE_HOLDS_FRACTION (&field->value))
return FALSE;
*value_numerator = gst_value_get_fraction_numerator (&field->value);
*value_denominator = gst_value_get_fraction_denominator (&field->value);
return TRUE;
}
typedef struct _GstStructureAbbreviation
{
gchar *type_name;
GType type;
}
GstStructureAbbreviation;
/* return a copy of an array of GstStructureAbbreviation containing all the
* known type_string, GType maps, including abbreviations for common types */
static GstStructureAbbreviation *
gst_structure_get_abbrs (gint * n_abbrs)
{
static GstStructureAbbreviation *abbrs = NULL;
static gint num = 0;
if (abbrs == NULL) {
/* dynamically generate the array */
GstStructureAbbreviation dyn_abbrs[] = {
{"int", G_TYPE_INT}
,
{"i", G_TYPE_INT}
,
{"float", G_TYPE_FLOAT}
,
{"f", G_TYPE_FLOAT}
,
{"double", G_TYPE_DOUBLE}
,
{"d", G_TYPE_DOUBLE}
,
{"buffer", GST_TYPE_BUFFER}
,
{"fourcc", GST_TYPE_FOURCC}
,
{"4", GST_TYPE_FOURCC}
,
{"fraction", GST_TYPE_FRACTION}
,
{"boolean", G_TYPE_BOOLEAN}
,
{"bool", G_TYPE_BOOLEAN}
,
{"b", G_TYPE_BOOLEAN}
,
{"string", G_TYPE_STRING}
,
{"str", G_TYPE_STRING}
,
{"s", G_TYPE_STRING}
,
{"structure", GST_TYPE_STRUCTURE}
};
num = G_N_ELEMENTS (dyn_abbrs);
/* permanently allocate and copy the array now */
abbrs = g_new0 (GstStructureAbbreviation, num);
memcpy (abbrs, dyn_abbrs, sizeof (GstStructureAbbreviation) * num);
}
*n_abbrs = num;
return abbrs;
}
/* given a type_name that could be a type abbreviation or a registered GType,
* return a matching GType */
static GType
gst_structure_gtype_from_abbr (const char *type_name)
{
int i;
GstStructureAbbreviation *abbrs;
gint n_abbrs;
g_return_val_if_fail (type_name != NULL, G_TYPE_INVALID);
abbrs = gst_structure_get_abbrs (&n_abbrs);
for (i = 0; i < n_abbrs; i++) {
if (strcmp (type_name, abbrs[i].type_name) == 0) {
return abbrs[i].type;
}
}
/* this is the fallback */
return g_type_from_name (type_name);
}
static const char *
gst_structure_to_abbr (GType type)
{
int i;
GstStructureAbbreviation *abbrs;
gint n_abbrs;
g_return_val_if_fail (type != G_TYPE_INVALID, NULL);
abbrs = gst_structure_get_abbrs (&n_abbrs);
for (i = 0; i < n_abbrs; i++) {
if (type == abbrs[i].type) {
return abbrs[i].type_name;
}
}
return g_type_name (type);
}
static GType
gst_structure_value_get_generic_type (GValue * val)
{
if (G_VALUE_TYPE (val) == GST_TYPE_LIST
|| G_VALUE_TYPE (val) == GST_TYPE_ARRAY) {
GArray *array = g_value_peek_pointer (val);
if (array->len > 0) {
GValue *value = &g_array_index (array, GValue, 0);
return gst_structure_value_get_generic_type (value);
} else {
return G_TYPE_INT;
}
} else if (G_VALUE_TYPE (val) == GST_TYPE_INT_RANGE) {
return G_TYPE_INT;
} else if (G_VALUE_TYPE (val) == GST_TYPE_DOUBLE_RANGE) {
return G_TYPE_DOUBLE;
} else if (G_VALUE_TYPE (val) == GST_TYPE_FRACTION_RANGE) {
return GST_TYPE_FRACTION;
}
return G_VALUE_TYPE (val);
}
gboolean
priv_gst_structure_append_to_gstring (const GstStructure * structure,
GString * s)
{
GstStructureField *field;
guint i, len;
g_return_val_if_fail (s != NULL, FALSE);
g_string_append (s, g_quark_to_string (structure->name));
len = structure->fields->len;
for (i = 0; i < len; i++) {
char *t;
GType type;
field = GST_STRUCTURE_FIELD (structure, i);
t = gst_value_serialize (&field->value);
type = gst_structure_value_get_generic_type (&field->value);
g_string_append_len (s, ", ", 2);
/* FIXME: do we need to escape fieldnames? */
g_string_append (s, g_quark_to_string (field->name));
g_string_append_len (s, "=(", 2);
g_string_append (s, gst_structure_to_abbr (type));
g_string_append_c (s, ')');
g_string_append (s, GST_STR_NULL (t));
g_free (t);
}
g_string_append_c (s, ';');
return TRUE;
}
/**
* gst_structure_to_string:
* @structure: a #GstStructure
*
* Converts @structure to a human-readable string representation.
*
* For debugging purposes its easier to do something like this:
* |[
* GST_LOG ("structure is %" GST_PTR_FORMAT, structure);
* ]|
* This prints the structure in human readble form.
*
* Returns: a pointer to string allocated by g_malloc(). g_free() after
* usage.
*/
gchar *
gst_structure_to_string (const GstStructure * structure)
{
GString *s;
/* NOTE: This function is potentially called by the debug system,
* so any calls to gst_log() (and GST_DEBUG(), GST_LOG(), etc.)
* should be careful to avoid recursion. This includes any functions
* called by gst_structure_to_string. In particular, calls should
* not use the GST_PTR_FORMAT extension. */
g_return_val_if_fail (structure != NULL, NULL);
/* we estimate a minimum size based on the number of fields in order to
* avoid unnecessary reallocs within GString */
s = g_string_sized_new (STRUCTURE_ESTIMATED_STRING_LEN (structure));
priv_gst_structure_append_to_gstring (structure, s);
return g_string_free (s, FALSE);
}
/*
* r will still point to the string. if end == next, the string will not be
* null-terminated. In all other cases it will be.
* end = pointer to char behind end of string, next = pointer to start of
* unread data.
* THIS FUNCTION MODIFIES THE STRING AND DETECTS INSIDE A NONTERMINATED STRING
*/
static gboolean
gst_structure_parse_string (gchar * s, gchar ** end, gchar ** next)
{
gchar *w;
if (*s == 0)
return FALSE;
if (*s != '"') {
int ret;
ret = gst_structure_parse_simple_string (s, end);
*next = *end;
return ret;
}
w = s;
s++;
while (*s != '"') {
if (*s == 0)
return FALSE;
if (*s == '\\') {
s++;
}
*w = *s;
w++;
s++;
}
s++;
*end = w;
*next = s;
return TRUE;
}
static gboolean
gst_structure_parse_range (gchar * s, gchar ** after, GValue * value,
GType type)
{
GValue value1 = { 0 };
GValue value2 = { 0 };
GType range_type;
gboolean ret;
if (*s != '[')
return FALSE;
s++;
ret = gst_structure_parse_value (s, &s, &value1, type);
if (ret == FALSE)
return FALSE;
while (g_ascii_isspace (*s))
s++;
if (*s != ',')
return FALSE;
s++;
while (g_ascii_isspace (*s))
s++;
ret = gst_structure_parse_value (s, &s, &value2, type);
if (ret == FALSE)
return FALSE;
while (g_ascii_isspace (*s))
s++;
if (*s != ']')
return FALSE;
s++;
if (G_VALUE_TYPE (&value1) != G_VALUE_TYPE (&value2))
return FALSE;
if (G_VALUE_TYPE (&value1) == G_TYPE_DOUBLE) {
range_type = GST_TYPE_DOUBLE_RANGE;
g_value_init (value, range_type);
gst_value_set_double_range (value, g_value_get_double (&value1),
g_value_get_double (&value2));
} else if (G_VALUE_TYPE (&value1) == G_TYPE_INT) {
range_type = GST_TYPE_INT_RANGE;
g_value_init (value, range_type);
gst_value_set_int_range (value, g_value_get_int (&value1),
g_value_get_int (&value2));
} else if (G_VALUE_TYPE (&value1) == GST_TYPE_FRACTION) {
range_type = GST_TYPE_FRACTION_RANGE;
g_value_init (value, range_type);
gst_value_set_fraction_range (value, &value1, &value2);
} else {
return FALSE;
}
*after = s;
return TRUE;
}
static gboolean
gst_structure_parse_any_list (gchar * s, gchar ** after, GValue * value,
GType type, GType list_type, char begin, char end)
{
GValue list_value = { 0 };
gboolean ret;
GArray *array;
g_value_init (value, list_type);
array = g_value_peek_pointer (value);
if (*s != begin)
return FALSE;
s++;
while (g_ascii_isspace (*s))
s++;
if (*s == end) {
s++;
*after = s;
return TRUE;
}
ret = gst_structure_parse_value (s, &s, &list_value, type);
if (ret == FALSE)
return FALSE;
g_array_append_val (array, list_value);
while (g_ascii_isspace (*s))
s++;
while (*s != end) {
if (*s != ',')
return FALSE;
s++;
while (g_ascii_isspace (*s))
s++;
memset (&list_value, 0, sizeof (list_value));
ret = gst_structure_parse_value (s, &s, &list_value, type);
if (ret == FALSE)
return FALSE;
g_array_append_val (array, list_value);
while (g_ascii_isspace (*s))
s++;
}
s++;
*after = s;
return TRUE;
}
static gboolean
gst_structure_parse_list (gchar * s, gchar ** after, GValue * value, GType type)
{
return gst_structure_parse_any_list (s, after, value, type, GST_TYPE_LIST,
'{', '}');
}
static gboolean
gst_structure_parse_array (gchar * s, gchar ** after, GValue * value,
GType type)
{
return gst_structure_parse_any_list (s, after, value, type,
GST_TYPE_ARRAY, '<', '>');
}
static gboolean
gst_structure_parse_simple_string (gchar * str, gchar ** end)
{
char *s = str;
while (GST_ASCII_IS_STRING (*s)) {
s++;
}
*end = s;
return (s != str);
}
static gboolean
gst_structure_parse_field (gchar * str,
gchar ** after, GstStructureField * field)
{
gchar *name;
gchar *name_end;
gchar *s;
gchar c;
s = str;
while (g_ascii_isspace (*s) || (s[0] == '\\' && g_ascii_isspace (s[1])))
s++;
name = s;
if (!gst_structure_parse_simple_string (s, &name_end))
return FALSE;
s = name_end;
while (g_ascii_isspace (*s) || (s[0] == '\\' && g_ascii_isspace (s[1])))
s++;
if (*s != '=')
return FALSE;
s++;
c = *name_end;
*name_end = '\0';
field->name = g_quark_from_string (name);
*name_end = c;
if (!gst_structure_parse_value (s, &s, &field->value, G_TYPE_INVALID))
return FALSE;
*after = s;
return TRUE;
}
static gboolean
gst_structure_parse_value (gchar * str,
gchar ** after, GValue * value, GType default_type)
{
gchar *type_name;
gchar *type_end;
gchar *value_s;
gchar *value_end;
gchar *s;
gchar c;
int ret = 0;
GType type = default_type;
s = str;
while (g_ascii_isspace (*s))
s++;
/* check if there's a (type_name) 'cast' */
type_name = NULL;
if (*s == '(') {
s++;
while (g_ascii_isspace (*s))
s++;
type_name = s;
if (!gst_structure_parse_simple_string (s, &type_end))
return FALSE;
s = type_end;
while (g_ascii_isspace (*s))
s++;
if (*s != ')')
return FALSE;
s++;
while (g_ascii_isspace (*s))
s++;
c = *type_end;
*type_end = 0;
type = gst_structure_gtype_from_abbr (type_name);
*type_end = c;
if (G_UNLIKELY (type == G_TYPE_INVALID))
return FALSE;
}
while (g_ascii_isspace (*s))
s++;
if (*s == '[') {
ret = gst_structure_parse_range (s, &s, value, type);
} else if (*s == '{') {
ret = gst_structure_parse_list (s, &s, value, type);
} else if (*s == '<') {
ret = gst_structure_parse_array (s, &s, value, type);
} else {
value_s = s;
if (G_UNLIKELY (!gst_structure_parse_string (s, &value_end, &s)))
return FALSE;
c = *value_end;
*value_end = '\0';
if (G_UNLIKELY (type == G_TYPE_INVALID)) {
GType try_types[] =
{ G_TYPE_INT, G_TYPE_DOUBLE, GST_TYPE_FRACTION, G_TYPE_BOOLEAN,
G_TYPE_STRING
};
int i;
for (i = 0; i < G_N_ELEMENTS (try_types); i++) {
g_value_init (value, try_types[i]);
ret = gst_value_deserialize (value, value_s);
if (ret)
break;
g_value_unset (value);
}
} else {
g_value_init (value, type);
ret = gst_value_deserialize (value, value_s);
if (G_UNLIKELY (!ret))
g_value_unset (value);
}
*value_end = c;
}
*after = s;
return ret;
}
/**
* gst_structure_from_string:
* @string: a string representation of a #GstStructure.
* @end: pointer to store the end of the string in.
*
* Creates a #GstStructure from a string representation.
* If end is not NULL, a pointer to the place inside the given string
* where parsing ended will be returned.
*
* Returns: a new #GstStructure or NULL when the string could not
* be parsed. Free with gst_structure_free() after use.
*/
GstStructure *
gst_structure_from_string (const gchar * string, gchar ** end)
{
char *name;
char *copy;
char *w;
char *r;
char save;
GstStructure *structure = NULL;
GstStructureField field;
g_return_val_if_fail (string != NULL, NULL);
copy = g_strdup (string);
r = copy;
/* skip spaces (FIXME: _isspace treats tabs and newlines as space!) */
while (*r && (g_ascii_isspace (*r) || (r[0] == '\\'
&& g_ascii_isspace (r[1]))))
r++;
name = r;
if (!gst_structure_parse_string (r, &w, &r)) {
GST_WARNING ("Failed to parse structure string");
goto error;
}
save = *w;
*w = '\0';
structure = gst_structure_empty_new (name);
*w = save;
if (G_UNLIKELY (structure == NULL))
goto error;
do {
while (*r && (g_ascii_isspace (*r) || (r[0] == '\\'
&& g_ascii_isspace (r[1]))))
r++;
if (*r == ';') {
/* end of structure, get the next char and finish */
r++;
break;
}
if (*r == '\0') {
/* accept \0 as end delimiter */
break;
}
if (*r != ',') {
GST_WARNING ("Failed to find delimiter, r=%s", r);
goto error;
}
r++;
while (*r && (g_ascii_isspace (*r) || (r[0] == '\\'
&& g_ascii_isspace (r[1]))))
r++;
memset (&field, 0, sizeof (field));
if (!gst_structure_parse_field (r, &r, &field))
goto error;
gst_structure_set_field (structure, &field);
} while (TRUE);
if (end)
*end = (char *) string + (r - copy);
else if (*r)
g_warning ("gst_structure_from_string did not consume whole string,"
" but caller did not provide end pointer (\"%s\")", string);
g_free (copy);
return structure;
error:
if (structure)
gst_structure_free (structure);
g_free (copy);
return NULL;
}
static void
gst_structure_transform_to_string (const GValue * src_value,
GValue * dest_value)
{
g_return_if_fail (src_value != NULL);
g_return_if_fail (dest_value != NULL);
dest_value->data[0].v_pointer =
gst_structure_to_string (src_value->data[0].v_pointer);
}
static GstStructure *
gst_structure_copy_conditional (const GstStructure * structure)
{
if (structure)
return gst_structure_copy (structure);
return NULL;
}
/* fixate utility functions */
/**
* gst_structure_fixate_field_nearest_int:
* @structure: a #GstStructure
* @field_name: a field in @structure
* @target: the target value of the fixation
*
* Fixates a #GstStructure by changing the given field to the nearest
* integer to @target that is a subset of the existing field.
*
* Returns: TRUE if the structure could be fixated
*/
gboolean
gst_structure_fixate_field_nearest_int (GstStructure * structure,
const char *field_name, int target)
{
const GValue *value;
g_return_val_if_fail (gst_structure_has_field (structure, field_name), FALSE);
g_return_val_if_fail (IS_MUTABLE (structure), FALSE);
value = gst_structure_get_value (structure, field_name);
if (G_VALUE_TYPE (value) == G_TYPE_INT) {
/* already fixed */
return FALSE;
} else if (G_VALUE_TYPE (value) == GST_TYPE_INT_RANGE) {
int x;
x = gst_value_get_int_range_min (value);
if (target < x)
target = x;
x = gst_value_get_int_range_max (value);
if (target > x)
target = x;
gst_structure_set (structure, field_name, G_TYPE_INT, target, NULL);
return TRUE;
} else if (G_VALUE_TYPE (value) == GST_TYPE_LIST) {
const GValue *list_value;
int i, n;
int best = 0;
int best_index = -1;
n = gst_value_list_get_size (value);
for (i = 0; i < n; i++) {
list_value = gst_value_list_get_value (value, i);
if (G_VALUE_TYPE (list_value) == G_TYPE_INT) {
int x = g_value_get_int (list_value);
if (best_index == -1 || (ABS (target - x) < ABS (target - best))) {
best_index = i;
best = x;
}
}
}
if (best_index != -1) {
gst_structure_set (structure, field_name, G_TYPE_INT, best, NULL);
return TRUE;
}
return FALSE;
}
return FALSE;
}
/**
* gst_structure_fixate_field_nearest_double:
* @structure: a #GstStructure
* @field_name: a field in @structure
* @target: the target value of the fixation
*
* Fixates a #GstStructure by changing the given field to the nearest
* double to @target that is a subset of the existing field.
*
* Returns: TRUE if the structure could be fixated
*/
gboolean
gst_structure_fixate_field_nearest_double (GstStructure * structure,
const char *field_name, double target)
{
const GValue *value;
g_return_val_if_fail (gst_structure_has_field (structure, field_name), FALSE);
g_return_val_if_fail (IS_MUTABLE (structure), FALSE);
value = gst_structure_get_value (structure, field_name);
if (G_VALUE_TYPE (value) == G_TYPE_DOUBLE) {
/* already fixed */
return FALSE;
} else if (G_VALUE_TYPE (value) == GST_TYPE_DOUBLE_RANGE) {
double x;
x = gst_value_get_double_range_min (value);
if (target < x)
target = x;
x = gst_value_get_double_range_max (value);
if (target > x)
target = x;
gst_structure_set (structure, field_name, G_TYPE_DOUBLE, target, NULL);
return TRUE;
} else if (G_VALUE_TYPE (value) == GST_TYPE_LIST) {
const GValue *list_value;
int i, n;
double best = 0;
int best_index = -1;
n = gst_value_list_get_size (value);
for (i = 0; i < n; i++) {
list_value = gst_value_list_get_value (value, i);
if (G_VALUE_TYPE (list_value) == G_TYPE_DOUBLE) {
double x = g_value_get_double (list_value);
if (best_index == -1 || (ABS (target - x) < ABS (target - best))) {
best_index = i;
best = x;
}
}
}
if (best_index != -1) {
gst_structure_set (structure, field_name, G_TYPE_DOUBLE, best, NULL);
return TRUE;
}
return FALSE;
}
return FALSE;
}
/**
* gst_structure_fixate_field_boolean:
* @structure: a #GstStructure
* @field_name: a field in @structure
* @target: the target value of the fixation
*
* Fixates a #GstStructure by changing the given @field_name field to the given
* @target boolean if that field is not fixed yet.
*
* Returns: TRUE if the structure could be fixated
*/
gboolean
gst_structure_fixate_field_boolean (GstStructure * structure,
const char *field_name, gboolean target)
{
const GValue *value;
g_return_val_if_fail (gst_structure_has_field (structure, field_name), FALSE);
g_return_val_if_fail (IS_MUTABLE (structure), FALSE);
value = gst_structure_get_value (structure, field_name);
if (G_VALUE_TYPE (value) == G_TYPE_BOOLEAN) {
/* already fixed */
return FALSE;
} else if (G_VALUE_TYPE (value) == GST_TYPE_LIST) {
const GValue *list_value;
int i, n;
int best = 0;
int best_index = -1;
n = gst_value_list_get_size (value);
for (i = 0; i < n; i++) {
list_value = gst_value_list_get_value (value, i);
if (G_VALUE_TYPE (list_value) == G_TYPE_BOOLEAN) {
gboolean x = g_value_get_boolean (list_value);
if (best_index == -1 || x == target) {
best_index = i;
best = x;
}
}
}
if (best_index != -1) {
gst_structure_set (structure, field_name, G_TYPE_BOOLEAN, best, NULL);
return TRUE;
}
return FALSE;
}
return FALSE;
}
/**
* gst_structure_fixate_field_nearest_fraction:
* @structure: a #GstStructure
* @field_name: a field in @structure
* @target_numerator: The numerator of the target value of the fixation
* @target_denominator: The denominator of the target value of the fixation
*
* Fixates a #GstStructure by changing the given field to the nearest
* fraction to @target_numerator/@target_denominator that is a subset
* of the existing field.
*
* Returns: TRUE if the structure could be fixated
*/
gboolean
gst_structure_fixate_field_nearest_fraction (GstStructure * structure,
const char *field_name, const gint target_numerator,
const gint target_denominator)
{
const GValue *value;
g_return_val_if_fail (gst_structure_has_field (structure, field_name), FALSE);
g_return_val_if_fail (IS_MUTABLE (structure), FALSE);
value = gst_structure_get_value (structure, field_name);
if (G_VALUE_TYPE (value) == GST_TYPE_FRACTION) {
/* already fixed */
return FALSE;
} else if (G_VALUE_TYPE (value) == GST_TYPE_FRACTION_RANGE) {
const GValue *x, *new_value;
GValue target = { 0 };
g_value_init (&target, GST_TYPE_FRACTION);
gst_value_set_fraction (&target, target_numerator, target_denominator);
new_value = &target;
x = gst_value_get_fraction_range_min (value);
if (gst_value_compare (&target, x) == GST_VALUE_LESS_THAN)
new_value = x;
x = gst_value_get_fraction_range_max (value);
if (gst_value_compare (&target, x) == GST_VALUE_GREATER_THAN)
new_value = x;
gst_structure_set_value (structure, field_name, new_value);
g_value_unset (&target);
return TRUE;
} else if (G_VALUE_TYPE (value) == GST_TYPE_LIST) {
const GValue *list_value;
int i, n;
const GValue *best = NULL;
gdouble target;
gdouble cur_diff;
gdouble best_diff = G_MAXDOUBLE;
target = (gdouble) target_numerator / (gdouble) target_denominator;
GST_DEBUG ("target %g, best %g", target, best_diff);
best = NULL;
n = gst_value_list_get_size (value);
for (i = 0; i < n; i++) {
list_value = gst_value_list_get_value (value, i);
if (G_VALUE_TYPE (list_value) == GST_TYPE_FRACTION) {
gint num, denom;
gdouble list_double;
num = gst_value_get_fraction_numerator (list_value);
denom = gst_value_get_fraction_denominator (list_value);
list_double = ((gdouble) num / (gdouble) denom);
cur_diff = target - list_double;
GST_DEBUG ("curr diff %g, list %g", cur_diff, list_double);
if (cur_diff < 0)
cur_diff = -cur_diff;
if (!best || cur_diff < best_diff) {
GST_DEBUG ("new best %g", list_double);
best = list_value;
best_diff = cur_diff;
}
}
}
if (best != NULL) {
gst_structure_set_value (structure, field_name, best);
return TRUE;
}
}
return FALSE;
}
/* our very own version of G_VALUE_LCOPY that allows NULL return locations
* (useful for message parsing functions where the return location is user
* supplied and the user may pass NULL if the value isn't of interest) */
#define GST_VALUE_LCOPY(value, var_args, flags, __error, fieldname) \
G_STMT_START { \
const GValue *_value = (value); \
guint _flags = (flags); \
GType _value_type = G_VALUE_TYPE (_value); \
GTypeValueTable *_vtable = g_type_value_table_peek (_value_type); \
gchar *_lcopy_format = _vtable->lcopy_format; \
GTypeCValue _cvalues[G_VALUE_COLLECT_FORMAT_MAX_LENGTH] = { { 0, }, }; \
guint _n_values = 0; \
\
while (*_lcopy_format != '\0') { \
g_assert (*_lcopy_format == G_VALUE_COLLECT_POINTER); \
_cvalues[_n_values++].v_pointer = va_arg ((var_args), gpointer); \
_lcopy_format++; \
} \
if (_n_values == 2 && !!_cvalues[0].v_pointer != !!_cvalues[1].v_pointer) { \
*(__error) = g_strdup_printf ("either all or none of the return " \
"locations for field '%s' need to be NULL", fieldname); \
} else if (_cvalues[0].v_pointer != NULL) { \
*(__error) = _vtable->lcopy_value (_value, _n_values, _cvalues, _flags); \
} \
} G_STMT_END
/**
* gst_structure_get_valist:
* @structure: a #GstStructure
* @first_fieldname: the name of the first field to read
* @args: variable arguments
*
* Parses the variable arguments and reads fields from @structure accordingly.
* valist-variant of gst_structure_get(). Look at the documentation of
* gst_structure_get() for more details.
*
* Returns: TRUE, or FALSE if there was a problem reading any of the fields
*
* Since: 0.10.24
*/
gboolean
gst_structure_get_valist (GstStructure * structure,
const char *first_fieldname, va_list args)
{
const char *field_name;
GType expected_type = G_TYPE_INVALID;
g_return_val_if_fail (GST_IS_STRUCTURE (structure), FALSE);
g_return_val_if_fail (first_fieldname != NULL, FALSE);
field_name = first_fieldname;
while (field_name) {
const GValue *val = NULL;
gchar *err = NULL;
expected_type = va_arg (args, GType);
val = gst_structure_get_value (structure, field_name);
if (val == NULL)
goto no_such_field;
if (G_VALUE_TYPE (val) != expected_type)
goto wrong_type;
GST_VALUE_LCOPY (val, args, 0, &err, field_name);
if (err) {
g_warning ("%s: %s", G_STRFUNC, err);
g_free (err);
return FALSE;
}
field_name = va_arg (args, const gchar *);
}
return TRUE;
/* ERRORS */
no_such_field:
{
GST_WARNING ("Expected field '%s' in structure: %" GST_PTR_FORMAT,
field_name, structure);
return FALSE;
}
wrong_type:
{
GST_WARNING ("Expected field '%s' in structure to be of type '%s', but "
"field was of type '%s': %" GST_PTR_FORMAT, field_name,
GST_STR_NULL (g_type_name (expected_type)),
G_VALUE_TYPE_NAME (gst_structure_get_value (structure, field_name)),
structure);
return FALSE;
}
}
/**
* gst_structure_id_get_valist:
* @structure: a #GstStructure
* @first_field_id: the quark of the first field to read
* @args: variable arguments
*
* Parses the variable arguments and reads fields from @structure accordingly.
* valist-variant of gst_structure_id_get(). Look at the documentation of
* gst_structure_id_get() for more details.
*
* Returns: TRUE, or FALSE if there was a problem reading any of the fields
*
* Since: 0.10.24
*/
gboolean
gst_structure_id_get_valist (GstStructure * structure, GQuark first_field_id,
va_list args)
{
GQuark field_id;
GType expected_type = G_TYPE_INVALID;
g_return_val_if_fail (GST_IS_STRUCTURE (structure), FALSE);
g_return_val_if_fail (first_field_id != 0, FALSE);
field_id = first_field_id;
while (field_id) {
const GValue *val = NULL;
gchar *err = NULL;
expected_type = va_arg (args, GType);
val = gst_structure_id_get_value (structure, field_id);
if (val == NULL)
goto no_such_field;
if (G_VALUE_TYPE (val) != expected_type)
goto wrong_type;
GST_VALUE_LCOPY (val, args, 0, &err, g_quark_to_string (field_id));
if (err) {
g_warning ("%s: %s", G_STRFUNC, err);
g_free (err);
return FALSE;
}
field_id = va_arg (args, GQuark);
}
return TRUE;
/* ERRORS */
no_such_field:
{
GST_WARNING ("Expected field '%s' in structure: %" GST_PTR_FORMAT,
GST_STR_NULL (g_quark_to_string (field_id)), structure);
return FALSE;
}
wrong_type:
{
GST_WARNING ("Expected field '%s' in structure to be of type '%s', but "
"field was of type '%s': %" GST_PTR_FORMAT,
g_quark_to_string (field_id),
GST_STR_NULL (g_type_name (expected_type)),
G_VALUE_TYPE_NAME (gst_structure_id_get_value (structure, field_id)),
structure);
return FALSE;
}
}
/**
* gst_structure_get:
* @structure: a #GstStructure
* @first_fieldname: the name of the first field to read
* @...: variable arguments
*
* Parses the variable arguments and reads fields from @structure accordingly.
* Variable arguments should be in the form field name, field type
* (as a GType), pointer(s) to a variable(s) to hold the return value(s).
* The last variable argument should be NULL.
*
* For refcounted (mini)objects you will acquire your own reference which
* you must release with a suitable _unref() when no longer needed. For
* strings and boxed types you will acquire a copy which you will need to
* release with either g_free() or the suiteable function for the boxed type.
*
* Returns: FALSE if there was a problem reading any of the fields (e.g.
* because the field requested did not exist, or was of a type other
* than the type specified), otherwise TRUE.
*
* Since: 0.10.24
*/
gboolean
gst_structure_get (GstStructure * structure, const char *first_fieldname, ...)
{
gboolean ret;
va_list args;
g_return_val_if_fail (GST_IS_STRUCTURE (structure), FALSE);
g_return_val_if_fail (first_fieldname != NULL, FALSE);
va_start (args, first_fieldname);
ret = gst_structure_get_valist (structure, first_fieldname, args);
va_end (args);
return ret;
}
/**
* gst_structure_id_get:
* @structure: a #GstStructure
* @first_field_id: the quark of the first field to read
* @...: variable arguments
*
* Parses the variable arguments and reads fields from @structure accordingly.
* Variable arguments should be in the form field id quark, field type
* (as a GType), pointer(s) to a variable(s) to hold the return value(s).
* The last variable argument should be NULL (technically it should be a
* 0 quark, but we require NULL so compilers that support it can check for
* the NULL terminator and warn if it's not there).
*
* This function is just like gst_structure_get() only that it is slightly
* more efficient since it saves the string-to-quark lookup in the global
* quark hashtable.
*
* For refcounted (mini)objects you will acquire your own reference which
* you must release with a suitable _unref() when no longer needed. For
* strings and boxed types you will acquire a copy which you will need to
* release with either g_free() or the suiteable function for the boxed type.
*
* Returns: FALSE if there was a problem reading any of the fields (e.g.
* because the field requested did not exist, or was of a type other
* than the type specified), otherwise TRUE.
*
* Since: 0.10.24
*/
gboolean
gst_structure_id_get (GstStructure * structure, GQuark first_field_id, ...)
{
gboolean ret;
va_list args;
g_return_val_if_fail (GST_IS_STRUCTURE (structure), FALSE);
g_return_val_if_fail (first_field_id != 0, FALSE);
va_start (args, first_field_id);
ret = gst_structure_id_get_valist (structure, first_field_id, args);
va_end (args);
return ret;
}
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