gstreamer/gst/gstsample.c
Sebastian Dröge 6fa351407a miniobject: Add parent pointers to the miniobject to influence writability
Every container of miniobjects now needs to store itself as parent in
the child object, and remove itself again at a later time.

A miniobject is only writable if there is at most one parent, and that
parent is writable itself, and if the reference count of the miniobject
is 1.

GstBuffer (for memories), GstBufferList (for buffers) and GstSample (for
caps, buffer, bufferlist) was updated accordingly.

Without this it was possible to have e.g. a bufferlist with refcount 2
in two places, modifying the same buffer with refcount 1 at the same
time.

https://bugzilla.gnome.org/show_bug.cgi?id=796692
2018-07-09 09:45:45 +02:00

425 lines
10 KiB
C

/* GStreamer
* Copyright (C) 2011 Wim Taymans <wim.taymans@gmail.com>
*
* gstsample.c: media sample
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:gstsample
* @title: GstSample
* @short_description: A media sample
* @see_also: #GstBuffer, #GstCaps, #GstSegment
*
* A #GstSample is a small object containing data, a type, timing and
* extra arbitrary information.
*/
#include "gst_private.h"
#include "gstsample.h"
GST_DEBUG_CATEGORY_STATIC (gst_sample_debug);
#define GST_CAT_DEFAULT gst_sample_debug
struct _GstSample
{
GstMiniObject mini_object;
GstBuffer *buffer;
GstCaps *caps;
GstSegment segment;
GstStructure *info;
GstBufferList *buffer_list;
};
GType _gst_sample_type = 0;
GST_DEFINE_MINI_OBJECT_TYPE (GstSample, gst_sample);
void
_priv_gst_sample_initialize (void)
{
_gst_sample_type = gst_sample_get_type ();
GST_DEBUG_CATEGORY_INIT (gst_sample_debug, "sample", 0, "GstSample debug");
}
static GstSample *
_gst_sample_copy (GstSample * sample)
{
GstSample *copy;
copy = gst_sample_new (sample->buffer, sample->caps, &sample->segment,
(sample->info) ? gst_structure_copy (sample->info) : NULL);
if (sample->buffer_list) {
copy->buffer_list = gst_buffer_list_ref (sample->buffer_list);
gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (copy->buffer_list),
GST_MINI_OBJECT_CAST (copy));
}
return copy;
}
static void
_gst_sample_free (GstSample * sample)
{
GST_LOG ("free %p", sample);
if (sample->buffer) {
gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (sample->buffer),
GST_MINI_OBJECT_CAST (sample));
gst_buffer_unref (sample->buffer);
}
if (sample->caps) {
gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (sample->caps),
GST_MINI_OBJECT_CAST (sample));
gst_caps_unref (sample->caps);
}
if (sample->info) {
gst_structure_set_parent_refcount (sample->info, NULL);
gst_structure_free (sample->info);
}
if (sample->buffer_list) {
gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (sample->buffer_list),
GST_MINI_OBJECT_CAST (sample));
gst_buffer_list_unref (sample->buffer_list);
}
g_slice_free1 (sizeof (GstSample), sample);
}
/**
* gst_sample_new:
* @buffer: (transfer none) (allow-none): a #GstBuffer, or %NULL
* @caps: (transfer none) (allow-none): a #GstCaps, or %NULL
* @segment: (transfer none) (allow-none): a #GstSegment, or %NULL
* @info: (transfer full) (allow-none): a #GstStructure, or %NULL
*
* Create a new #GstSample with the provided details.
*
* Free-function: gst_sample_unref
*
* Returns: (transfer full): the new #GstSample. gst_sample_unref()
* after usage.
*/
GstSample *
gst_sample_new (GstBuffer * buffer, GstCaps * caps, const GstSegment * segment,
GstStructure * info)
{
GstSample *sample;
sample = g_slice_new0 (GstSample);
GST_LOG ("new %p", sample);
gst_mini_object_init (GST_MINI_OBJECT_CAST (sample), 0, _gst_sample_type,
(GstMiniObjectCopyFunction) _gst_sample_copy, NULL,
(GstMiniObjectFreeFunction) _gst_sample_free);
if (buffer) {
sample->buffer = gst_buffer_ref (buffer);
gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (sample->buffer),
GST_MINI_OBJECT_CAST (sample));
}
if (caps) {
sample->caps = gst_caps_ref (caps);
gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (sample->caps),
GST_MINI_OBJECT_CAST (sample));
}
/* FIXME 2.0: initialize with GST_FORMAT_UNDEFINED by default */
if (segment)
gst_segment_copy_into (segment, &sample->segment);
else
gst_segment_init (&sample->segment, GST_FORMAT_TIME);
if (info) {
if (!gst_structure_set_parent_refcount (info,
&sample->mini_object.refcount))
goto had_parent;
sample->info = info;
}
return sample;
/* ERRORS */
had_parent:
{
gst_sample_unref (sample);
g_warning ("structure is already owned by another object");
return NULL;
}
}
/**
* gst_sample_get_buffer:
* @sample: a #GstSample
*
* Get the buffer associated with @sample
*
* Returns: (transfer none) (nullable): the buffer of @sample or %NULL
* when there is no buffer. The buffer remains valid as long as
* @sample is valid. If you need to hold on to it for longer than
* that, take a ref to the buffer with gst_buffer_ref().
*/
GstBuffer *
gst_sample_get_buffer (GstSample * sample)
{
g_return_val_if_fail (GST_IS_SAMPLE (sample), NULL);
return sample->buffer;
}
/**
* gst_sample_get_caps:
* @sample: a #GstSample
*
* Get the caps associated with @sample
*
* Returns: (transfer none) (nullable): the caps of @sample or %NULL
* when there is no caps. The caps remain valid as long as @sample is
* valid. If you need to hold on to the caps for longer than that,
* take a ref to the caps with gst_caps_ref().
*/
GstCaps *
gst_sample_get_caps (GstSample * sample)
{
g_return_val_if_fail (GST_IS_SAMPLE (sample), NULL);
return sample->caps;
}
/**
* gst_sample_get_segment:
* @sample: a #GstSample
*
* Get the segment associated with @sample
*
* Returns: (transfer none): the segment of @sample.
* The segment remains valid as long as @sample is valid.
*/
GstSegment *
gst_sample_get_segment (GstSample * sample)
{
g_return_val_if_fail (GST_IS_SAMPLE (sample), NULL);
return &sample->segment;
}
/**
* gst_sample_get_info:
* @sample: a #GstSample
*
* Get extra information associated with @sample.
*
* Returns: (transfer none) (nullable): the extra info of @sample.
* The info remains valid as long as @sample is valid.
*/
const GstStructure *
gst_sample_get_info (GstSample * sample)
{
g_return_val_if_fail (GST_IS_SAMPLE (sample), NULL);
return sample->info;
}
/**
* gst_sample_get_buffer_list:
* @sample: a #GstSample
*
* Get the buffer list associated with @sample
*
* Returns: (transfer none) (nullable): the buffer list of @sample or %NULL
* when there is no buffer list. The buffer list remains valid as long as
* @sample is valid. If you need to hold on to it for longer than
* that, take a ref to the buffer list with gst_mini_object_ref ().
*
* Since: 1.6
*/
GstBufferList *
gst_sample_get_buffer_list (GstSample * sample)
{
g_return_val_if_fail (GST_IS_SAMPLE (sample), NULL);
return sample->buffer_list;
}
/**
* gst_sample_set_buffer_list:
* @sample: a #GstSample
* @buffer_list: a #GstBufferList
*
* Set the buffer list associated with @sample. @sample must be writable.
*
* Since: 1.6
*/
void
gst_sample_set_buffer_list (GstSample * sample, GstBufferList * buffer_list)
{
GstBufferList *old = NULL;
g_return_if_fail (GST_IS_SAMPLE (sample));
g_return_if_fail (gst_sample_is_writable (sample));
old = sample->buffer_list;
if (old == buffer_list)
return;
if (buffer_list) {
sample->buffer_list = gst_buffer_list_ref (buffer_list);
gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (sample->buffer_list),
GST_MINI_OBJECT_CAST (sample));
}
if (old) {
gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (old),
GST_MINI_OBJECT_CAST (sample));
gst_buffer_list_unref (old);
}
}
/**
* gst_sample_set_buffer:
* @sample: A #GstSample
* @buffer: (transfer none): A #GstBuffer
*
* Set the buffer associated with @sample. @sample must be writable.
*
* Since: 1.16
*/
void
gst_sample_set_buffer (GstSample * sample, GstBuffer * buffer)
{
GstBuffer *old = NULL;
g_return_if_fail (GST_IS_SAMPLE (sample));
g_return_if_fail (gst_sample_is_writable (sample));
old = sample->buffer;
if (old == buffer)
return;
if (buffer) {
sample->buffer = gst_buffer_ref (buffer);
gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (sample->buffer),
GST_MINI_OBJECT_CAST (sample));
}
if (old) {
gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (old),
GST_MINI_OBJECT_CAST (sample));
gst_buffer_unref (old);
}
}
/**
* gst_sample_set_caps:
* @sample: A #GstSample
* @caps: (transfer none): A #GstCaps
*
* Set the caps associated with @sample. @sample must be writable.
*
* Since: 1.16
*/
void
gst_sample_set_caps (GstSample * sample, GstCaps * caps)
{
GstCaps *old = NULL;
g_return_if_fail (GST_IS_SAMPLE (sample));
g_return_if_fail (gst_sample_is_writable (sample));
old = sample->caps;
if (old == caps)
return;
if (caps) {
sample->caps = gst_caps_ref (caps);
gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (sample->caps),
GST_MINI_OBJECT_CAST (sample));
}
if (old) {
gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (old),
GST_MINI_OBJECT_CAST (sample));
gst_caps_unref (old);
}
}
/**
* gst_sample_set_segment:
* @sample: A #GstSample
* @segment: (transfer none): A #GstSegment
*
* Set the segment associated with @sample. @sample must be writable.
*
* Since: 1.16
*/
void
gst_sample_set_segment (GstSample * sample, const GstSegment * segment)
{
g_return_if_fail (GST_IS_SAMPLE (sample));
g_return_if_fail (gst_sample_is_writable (sample));
/* FIXME 2.0: initialize with GST_FORMAT_UNDEFINED by default */
if (segment)
gst_segment_copy_into (segment, &sample->segment);
else
gst_segment_init (&sample->segment, GST_FORMAT_TIME);
}
/**
* gst_sample_set_info:
* @sample: A #GstSample
* @info: (transfer full): A #GstStructure
*
* Set the info structure associated with @sample. @sample must be writable,
* and @info must not have a parent set already.
*
* Since: 1.16
*/
gboolean
gst_sample_set_info (GstSample * sample, GstStructure * info)
{
g_return_val_if_fail (GST_IS_SAMPLE (sample), FALSE);
g_return_val_if_fail (gst_sample_is_writable (sample), FALSE);
if (info) {
if (!gst_structure_set_parent_refcount (info,
&sample->mini_object.refcount))
goto had_parent;
}
if (sample->info) {
gst_structure_set_parent_refcount (sample->info, NULL);
gst_structure_free (sample->info);
}
sample->info = info;
return TRUE;
had_parent:
g_warning ("structure is already owned by another object");
return FALSE;
}