2 * Copyright (C) 2010 Wim Taymans <wim.taymans@gmail.com>
4 * gstbufferpool.c: GstBufferPool baseclass
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 02111-1307, USA.
23 * SECTION:gstbufferpool
24 * @short_description: Pool for buffers
25 * @see_also: #GstBuffer
29 #include "gst_private.h"
30 #include "glib-compat-private.h"
36 #include <sys/types.h>
38 #include "gstatomicqueue.h"
44 #include "gstbufferpool.h"
46 GST_DEBUG_CATEGORY_STATIC (gst_buffer_pool_debug);
47 #define GST_CAT_DEFAULT gst_buffer_pool_debug
49 #define GST_BUFFER_POOL_GET_PRIVATE(obj) \
50 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BUFFER_POOL, GstBufferPoolPrivate))
52 #define GST_BUFFER_POOL_LOCK(pool) (g_rec_mutex_lock(&pool->priv->rec_lock))
53 #define GST_BUFFER_POOL_UNLOCK(pool) (g_rec_mutex_unlock(&pool->priv->rec_lock))
55 struct _GstBufferPoolPrivate
57 GstAtomicQueue *queue;
83 static void gst_buffer_pool_finalize (GObject * object);
85 G_DEFINE_TYPE (GstBufferPool, gst_buffer_pool, GST_TYPE_OBJECT);
87 static gboolean default_start (GstBufferPool * pool);
88 static gboolean default_stop (GstBufferPool * pool);
89 static gboolean default_set_config (GstBufferPool * pool,
90 GstStructure * config);
91 static GstFlowReturn default_alloc_buffer (GstBufferPool * pool,
92 GstBuffer ** buffer, GstBufferPoolParams * params);
93 static GstFlowReturn default_acquire_buffer (GstBufferPool * pool,
94 GstBuffer ** buffer, GstBufferPoolParams * params);
95 static void default_reset_buffer (GstBufferPool * pool, GstBuffer * buffer,
96 GstBufferPoolParams * params);
97 static void default_free_buffer (GstBufferPool * pool, GstBuffer * buffer);
98 static void default_release_buffer (GstBufferPool * pool, GstBuffer * buffer);
101 gst_buffer_pool_class_init (GstBufferPoolClass * klass)
103 GObjectClass *gobject_class = (GObjectClass *) klass;
105 g_type_class_add_private (klass, sizeof (GstBufferPoolPrivate));
107 gobject_class->finalize = gst_buffer_pool_finalize;
109 klass->start = default_start;
110 klass->stop = default_stop;
111 klass->set_config = default_set_config;
112 klass->acquire_buffer = default_acquire_buffer;
113 klass->reset_buffer = default_reset_buffer;
114 klass->alloc_buffer = default_alloc_buffer;
115 klass->release_buffer = default_release_buffer;
116 klass->free_buffer = default_free_buffer;
118 GST_DEBUG_CATEGORY_INIT (gst_buffer_pool_debug, "bufferpool", 0,
123 gst_buffer_pool_init (GstBufferPool * pool)
125 pool->priv = GST_BUFFER_POOL_GET_PRIVATE (pool);
127 g_rec_mutex_init (&pool->priv->rec_lock);
129 pool->priv->poll = gst_poll_new_timer ();
130 pool->priv->queue = gst_atomic_queue_new (10);
132 pool->priv->active = FALSE;
133 pool->priv->configured = FALSE;
134 pool->priv->started = FALSE;
136 gst_structure_new_id_empty (GST_QUARK (BUFFER_POOL_CONFIG));
137 gst_buffer_pool_config_set (pool->priv->config, NULL, 0, 0, 0, 0, 0, 0);
138 gst_poll_write_control (pool->priv->poll);
140 GST_DEBUG_OBJECT (pool, "created");
144 gst_buffer_pool_finalize (GObject * object)
148 pool = GST_BUFFER_POOL_CAST (object);
150 GST_DEBUG_OBJECT (pool, "finalize");
152 gst_buffer_pool_set_active (pool, FALSE);
153 gst_atomic_queue_unref (pool->priv->queue);
154 gst_poll_free (pool->priv->poll);
155 gst_structure_free (pool->priv->config);
156 g_rec_mutex_clear (&pool->priv->rec_lock);
158 G_OBJECT_CLASS (gst_buffer_pool_parent_class)->finalize (object);
162 * gst_buffer_pool_new:
164 * Creates a new #GstBufferPool instance.
166 * Returns: (transfer full): a new #GstBufferPool instance
169 gst_buffer_pool_new (void)
171 GstBufferPool *result;
173 result = g_object_newv (GST_TYPE_BUFFER_POOL, 0, NULL);
174 GST_DEBUG_OBJECT (result, "created new buffer pool");
180 default_alloc_buffer (GstBufferPool * pool, GstBuffer ** buffer,
181 GstBufferPoolParams * params)
183 GstBufferPoolPrivate *priv = pool->priv;
186 *buffer = gst_buffer_new ();
189 gst_allocator_alloc (NULL, priv->size + priv->prefix + priv->padding,
191 gst_memory_resize (mem, priv->prefix, priv->size);
192 gst_buffer_take_memory (*buffer, -1, mem);
198 mark_meta_pooled (GstBuffer * buffer, GstMeta ** meta, gpointer user_data)
200 GstBufferPool *pool = user_data;
202 GST_DEBUG_OBJECT (pool, "marking meta %p as POOLED in buffer %p", *meta,
204 GST_META_FLAG_SET (*meta, GST_META_FLAG_POOLED);
209 /* the default implementation for preallocating the buffers
212 default_start (GstBufferPool * pool)
215 GstBufferPoolPrivate *priv = pool->priv;
216 GstBufferPoolClass *pclass;
218 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
220 /* no alloc function, error */
221 if (G_UNLIKELY (pclass->alloc_buffer == NULL))
224 /* we need to prealloc buffers */
225 for (i = 0; i < priv->min_buffers; i++) {
228 if (pclass->alloc_buffer (pool, &buffer, NULL) != GST_FLOW_OK)
231 gst_buffer_foreach_meta (buffer, mark_meta_pooled, pool);
232 GST_LOG_OBJECT (pool, "prealloced buffer %d: %p", i, buffer);
233 /* release to the queue, we call the vmethod directly, we don't need to do
234 * the other refcount handling right now. */
235 if (G_LIKELY (pclass->release_buffer))
236 pclass->release_buffer (pool, buffer);
243 GST_WARNING_OBJECT (pool, "no alloc function");
248 GST_WARNING_OBJECT (pool, "alloc function failed");
253 /* must be called with the lock */
255 do_start (GstBufferPool * pool)
257 if (!pool->priv->started) {
258 GstBufferPoolClass *pclass;
260 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
262 GST_LOG_OBJECT (pool, "starting");
263 /* start the pool, subclasses should allocate buffers and put them
265 if (G_LIKELY (pclass->start)) {
266 if (!pclass->start (pool))
269 pool->priv->started = TRUE;
276 default_free_buffer (GstBufferPool * pool, GstBuffer * buffer)
278 gst_buffer_unref (buffer);
281 /* must be called with the lock */
283 default_stop (GstBufferPool * pool)
286 GstBufferPoolClass *pclass;
288 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
291 while ((buffer = gst_atomic_queue_pop (pool->priv->queue))) {
292 GST_LOG_OBJECT (pool, "freeing %p", buffer);
293 gst_poll_read_control (pool->priv->poll);
295 if (G_LIKELY (pclass->free_buffer))
296 pclass->free_buffer (pool, buffer);
301 /* must be called with the lock */
303 do_stop (GstBufferPool * pool)
305 if (pool->priv->started) {
306 GstBufferPoolClass *pclass;
308 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
310 GST_LOG_OBJECT (pool, "stopping");
311 if (G_LIKELY (pclass->stop)) {
312 if (!pclass->stop (pool))
315 pool->priv->started = FALSE;
321 * gst_buffer_pool_set_active:
322 * @pool: a #GstBufferPool
323 * @active: the new active state
325 * Control the active state of @pool. When the pool is active, new calls to
326 * gst_buffer_pool_acquire_buffer() will return with GST_FLOW_FLUSHING.
328 * Activating the bufferpool will preallocate all resources in the pool based on
329 * the configuration of the pool.
331 * Deactivating will free the resources again when there are no outstanding
332 * buffers. When there are outstanding buffers, they will be freed as soon as
333 * they are all returned to the pool.
335 * Returns: %FALSE when the pool was not configured or when preallocation of the
339 gst_buffer_pool_set_active (GstBufferPool * pool, gboolean active)
343 g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), FALSE);
345 GST_LOG_OBJECT (pool, "active %d", active);
347 GST_BUFFER_POOL_LOCK (pool);
348 /* just return if we are already in the right state */
349 if (pool->priv->active == active)
352 /* we need to be configured */
353 if (!pool->priv->configured)
357 if (!do_start (pool))
360 /* unset the flushing state now */
361 gst_poll_read_control (pool->priv->poll);
362 g_atomic_int_set (&pool->flushing, 0);
366 /* set to flushing first */
367 g_atomic_int_set (&pool->flushing, 1);
368 gst_poll_write_control (pool->priv->poll);
370 /* when all buffers are in the pool, free them. Else they will be
371 * freed when they are released */
372 outstanding = g_atomic_int_get (&pool->priv->outstanding);
373 GST_LOG_OBJECT (pool, "outstanding buffers %d", outstanding);
374 if (outstanding == 0) {
379 pool->priv->active = active;
380 GST_BUFFER_POOL_UNLOCK (pool);
386 GST_DEBUG_OBJECT (pool, "pool was in the right state");
387 GST_BUFFER_POOL_UNLOCK (pool);
392 GST_ERROR_OBJECT (pool, "pool was not configured");
393 GST_BUFFER_POOL_UNLOCK (pool);
398 GST_ERROR_OBJECT (pool, "start failed");
399 GST_BUFFER_POOL_UNLOCK (pool);
404 GST_WARNING_OBJECT (pool, "stop failed");
405 GST_BUFFER_POOL_UNLOCK (pool);
411 * gst_buffer_pool_is_active:
412 * @pool: a #GstBufferPool
414 * Check if @pool is active. A pool can be activated with the
415 * gst_buffer_pool_set_active() call.
417 * Returns: %TRUE when the pool is active.
420 gst_buffer_pool_is_active (GstBufferPool * pool)
424 GST_BUFFER_POOL_LOCK (pool);
425 res = pool->priv->active;
426 GST_BUFFER_POOL_UNLOCK (pool);
432 default_set_config (GstBufferPool * pool, GstStructure * config)
434 GstBufferPoolPrivate *priv = pool->priv;
436 guint size, min_buffers, max_buffers;
437 guint prefix, padding, align;
439 /* parse the config and keep around */
440 if (!gst_buffer_pool_config_get (config, &caps, &size, &min_buffers,
441 &max_buffers, &prefix, &padding, &align))
444 GST_DEBUG_OBJECT (pool, "config %" GST_PTR_FORMAT, config);
447 priv->min_buffers = min_buffers;
448 priv->max_buffers = max_buffers;
449 priv->prefix = prefix;
450 priv->padding = padding;
457 GST_WARNING_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config);
463 * gst_buffer_pool_set_config:
464 * @pool: a #GstBufferPool
465 * @config: (transfer full): a #GstStructure
467 * Set the configuration of the pool. The pool must be inactive and all buffers
468 * allocated form this pool must be returned or else this function will do
469 * nothing and return FALSE.
471 * @config is a #GstStructure that contains the configuration parameters for
472 * the pool. A default and mandatory set of parameters can be configured with
473 * gst_buffer_pool_config_set(). This function takes ownership of @config.
475 * Returns: TRUE when the configuration could be set.
478 gst_buffer_pool_set_config (GstBufferPool * pool, GstStructure * config)
481 GstBufferPoolClass *pclass;
483 g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), FALSE);
484 g_return_val_if_fail (config != NULL, FALSE);
486 GST_BUFFER_POOL_LOCK (pool);
487 /* can't change the settings when active */
488 if (pool->priv->active)
491 /* we can't change when outstanding buffers */
492 if (g_atomic_int_get (&pool->priv->outstanding) != 0)
493 goto have_outstanding;
495 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
497 /* set the new config */
498 if (G_LIKELY (pclass->set_config))
499 result = pclass->set_config (pool, config);
504 if (pool->priv->config)
505 gst_structure_free (pool->priv->config);
506 pool->priv->config = config;
508 /* now we are configured */
509 pool->priv->configured = TRUE;
511 gst_structure_free (config);
513 GST_BUFFER_POOL_UNLOCK (pool);
520 gst_structure_free (config);
521 GST_WARNING_OBJECT (pool, "can't change config, we are active");
522 GST_BUFFER_POOL_UNLOCK (pool);
527 gst_structure_free (config);
528 GST_WARNING_OBJECT (pool, "can't change config, have outstanding buffers");
529 GST_BUFFER_POOL_UNLOCK (pool);
535 * gst_buffer_pool_get_config:
536 * @pool: a #GstBufferPool
538 * Get a copy of the current configuration of the pool. This configuration
539 * can either be modified and used for the gst_buffer_pool_set_config() call
540 * or it must be freed after usage.
542 * Returns: (transfer full): a copy of the current configuration of @pool. use
543 * gst_structure_free() after usage or gst_buffer_pool_set_config().
546 gst_buffer_pool_get_config (GstBufferPool * pool)
548 GstStructure *result;
550 g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), NULL);
552 GST_BUFFER_POOL_UNLOCK (pool);
553 result = gst_structure_copy (pool->priv->config);
554 GST_BUFFER_POOL_UNLOCK (pool);
559 static const gchar *empty_option[] = { NULL };
562 * gst_buffer_pool_get_options:
563 * @pool: a #GstBufferPool
565 * Get a NULL terminated array of string with supported bufferpool options for
566 * @pool. An option would typically be enabled with
567 * gst_buffer_pool_config_add_option().
569 * Returns: (array zero-terminated=1) (transfer none): a NULL terminated array of strings.
572 gst_buffer_pool_get_options (GstBufferPool * pool)
574 GstBufferPoolClass *pclass;
575 const gchar **result;
577 g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), NULL);
579 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
581 if (G_LIKELY (pclass->get_options)) {
582 if ((result = pclass->get_options (pool)) == NULL)
585 result = empty_option;
592 g_warning ("bufferpool subclass returned NULL options");
598 * gst_buffer_pool_has_option:
599 * @pool: a #GstBufferPool
602 * Check if the bufferpool supports @option.
604 * Returns: a NULL terminated array of strings.
607 gst_buffer_pool_has_option (GstBufferPool * pool, const gchar * option)
610 const gchar **options;
612 g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), FALSE);
613 g_return_val_if_fail (option != NULL, FALSE);
615 options = gst_buffer_pool_get_options (pool);
617 for (i = 0; options[i]; i++) {
618 if (g_str_equal (options[i], option))
625 * gst_buffer_pool_config_set:
626 * @config: a #GstBufferPool configuration
627 * @caps: caps for the buffers
628 * @size: the size of each buffer, not including prefix and padding
629 * @min_buffers: the minimum amount of buffers to allocate.
630 * @max_buffers: the maximum amount of buffers to allocate or 0 for unlimited.
631 * @prefix: prefix each buffer with this many bytes
632 * @padding: pad each buffer with this many bytes
633 * @align: alignment of the buffer data.
635 * Configure @config with the given parameters.
638 gst_buffer_pool_config_set (GstStructure * config, const GstCaps * caps,
639 guint size, guint min_buffers, guint max_buffers, guint prefix,
640 guint padding, guint align)
642 g_return_if_fail (config != NULL);
644 gst_structure_id_set (config,
645 GST_QUARK (CAPS), GST_TYPE_CAPS, caps,
646 GST_QUARK (SIZE), G_TYPE_UINT, size,
647 GST_QUARK (MIN_BUFFERS), G_TYPE_UINT, min_buffers,
648 GST_QUARK (MAX_BUFFERS), G_TYPE_UINT, max_buffers,
649 GST_QUARK (PREFIX), G_TYPE_UINT, prefix,
650 GST_QUARK (PADDING), G_TYPE_UINT, padding,
651 GST_QUARK (ALIGN), G_TYPE_UINT, align, NULL);
655 * gst_buffer_pool_config_add_option:
656 * @config: a #GstBufferPool configuration
657 * @option: an option to add
659 * Enabled the option in @config. This will instruct the @bufferpool to enable
660 * the specified option on the buffers that it allocates.
662 * The supported options by @pool can be retrieved with gst_buffer_pool_get_options().
665 gst_buffer_pool_config_add_option (GstStructure * config, const gchar * option)
668 GValue option_value = { 0, };
671 g_return_if_fail (config != NULL);
673 value = gst_structure_id_get_value (config, GST_QUARK (OPTIONS));
675 len = gst_value_array_get_size (value);
676 for (i = 0; i < len; ++i) {
677 const GValue *nth_val = gst_value_array_get_value (value, i);
679 if (g_str_equal (option, g_value_get_string (nth_val)))
683 GValue new_array_val = { 0, };
685 g_value_init (&new_array_val, GST_TYPE_ARRAY);
686 gst_structure_id_take_value (config, GST_QUARK (OPTIONS), &new_array_val);
687 value = gst_structure_id_get_value (config, GST_QUARK (OPTIONS));
689 g_value_init (&option_value, G_TYPE_STRING);
690 g_value_set_string (&option_value, option);
691 gst_value_array_append_value ((GValue *) value, &option_value);
692 g_value_unset (&option_value);
696 * gst_buffer_pool_config_n_options:
697 * @config: a #GstBufferPool configuration
699 * Retrieve the number of values currently stored in the
700 * options array of the @config structure.
702 * Returns: the options array size as a #guint.
705 gst_buffer_pool_config_n_options (GstStructure * config)
710 g_return_val_if_fail (config != NULL, 0);
712 value = gst_structure_id_get_value (config, GST_QUARK (OPTIONS));
714 size = gst_value_array_get_size (value);
720 * gst_buffer_pool_config_get_option:
721 * @config: a #GstBufferPool configuration
722 * @index: position in the option array to read
724 * Parse an available @config and get the option
725 * at @index of the options API array.
727 * Returns: a #gchar of the option at @index.
730 gst_buffer_pool_config_get_option (GstStructure * config, guint index)
733 const gchar *ret = NULL;
735 g_return_val_if_fail (config != NULL, 0);
737 value = gst_structure_id_get_value (config, GST_QUARK (OPTIONS));
739 const GValue *option_value;
741 option_value = gst_value_array_get_value (value, index);
743 ret = g_value_get_string (option_value);
749 * gst_buffer_pool_config_has_option:
750 * @config: a #GstBufferPool configuration
753 * Check if @config contains @option
755 * Returns: TRUE if the options array contains @option.
758 gst_buffer_pool_config_has_option (GstStructure * config, const gchar * option)
763 g_return_val_if_fail (config != NULL, 0);
765 value = gst_structure_id_get_value (config, GST_QUARK (OPTIONS));
767 len = gst_value_array_get_size (value);
768 for (i = 0; i < len; ++i) {
769 const GValue *nth_val = gst_value_array_get_value (value, i);
771 if (g_str_equal (option, g_value_get_string (nth_val)))
779 * gst_buffer_pool_config_get:
780 * @config: (transfer none): a #GstBufferPool configuration
781 * @caps: (out): the caps of buffers
782 * @size: (out): the size of each buffer, not including prefix and padding
783 * @min_buffers: (out): the minimum amount of buffers to allocate.
784 * @max_buffers: (out): the maximum amount of buffers to allocate or 0 for unlimited.
785 * @prefix: (out): prefix each buffer with this many bytes
786 * @padding: (out): pad each buffer with this many bytes
787 * @align: (out): alignment of the buffer data.
789 * Get the configuration values from @config.
792 gst_buffer_pool_config_get (GstStructure * config, const GstCaps ** caps,
793 guint * size, guint * min_buffers, guint * max_buffers, guint * prefix,
794 guint * padding, guint * align)
796 g_return_val_if_fail (config != NULL, FALSE);
798 return gst_structure_id_get (config,
799 GST_QUARK (CAPS), GST_TYPE_CAPS, caps,
800 GST_QUARK (SIZE), G_TYPE_UINT, size,
801 GST_QUARK (MIN_BUFFERS), G_TYPE_UINT, min_buffers,
802 GST_QUARK (MAX_BUFFERS), G_TYPE_UINT, max_buffers,
803 GST_QUARK (PREFIX), G_TYPE_UINT, prefix,
804 GST_QUARK (PADDING), G_TYPE_UINT, padding,
805 GST_QUARK (ALIGN), G_TYPE_UINT, align, NULL);
809 default_acquire_buffer (GstBufferPool * pool, GstBuffer ** buffer,
810 GstBufferPoolParams * params)
812 GstFlowReturn result;
813 GstBufferPoolClass *pclass;
814 GstBufferPoolPrivate *priv = pool->priv;
816 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
819 if (G_UNLIKELY (GST_BUFFER_POOL_IS_FLUSHING (pool)))
822 /* try to get a buffer from the queue */
823 *buffer = gst_atomic_queue_pop (pool->priv->queue);
824 if (G_LIKELY (*buffer)) {
825 gst_poll_read_control (pool->priv->poll);
826 result = GST_FLOW_OK;
827 GST_LOG_OBJECT (pool, "acquired buffer %p", *buffer);
832 if (priv->max_buffers == 0) {
833 /* no max_buffers, we allocate some more */
834 if (G_LIKELY (pclass->alloc_buffer)) {
835 result = pclass->alloc_buffer (pool, buffer, params);
836 if (result == GST_FLOW_OK && *buffer)
837 gst_buffer_foreach_meta (*buffer, mark_meta_pooled, pool);
839 result = GST_FLOW_ERROR;
841 result = GST_FLOW_NOT_SUPPORTED;
842 GST_LOG_OBJECT (pool, "alloc buffer %p", *buffer);
846 /* check if we need to wait */
847 if (params && (params->flags & GST_BUFFER_POOL_FLAG_DONTWAIT)) {
848 GST_LOG_OBJECT (pool, "no more buffers");
849 result = GST_FLOW_EOS;
854 GST_LOG_OBJECT (pool, "waiting for free buffers");
855 gst_poll_wait (pool->priv->poll, GST_CLOCK_TIME_NONE);
863 GST_DEBUG_OBJECT (pool, "we are flushing");
864 return GST_FLOW_FLUSHING;
869 dec_outstanding (GstBufferPool * pool)
871 if (g_atomic_int_dec_and_test (&pool->priv->outstanding)) {
872 /* all buffers are returned to the pool, see if we need to free them */
873 if (GST_BUFFER_POOL_IS_FLUSHING (pool)) {
874 /* take the lock so that set_active is not run concurrently */
875 GST_BUFFER_POOL_LOCK (pool);
876 /* recheck the flushing state in the lock, the pool could have been
877 * set to active again */
878 if (GST_BUFFER_POOL_IS_FLUSHING (pool))
881 GST_BUFFER_POOL_UNLOCK (pool);
887 remove_meta_unpooled (GstBuffer * buffer, GstMeta ** meta, gpointer user_data)
889 if (!GST_META_FLAG_IS_SET (*meta, GST_META_FLAG_POOLED))
895 default_reset_buffer (GstBufferPool * pool, GstBuffer * buffer,
896 GstBufferPoolParams * params)
898 GST_BUFFER_FLAGS (buffer) = 0;
900 GST_BUFFER_PTS (buffer) = GST_CLOCK_TIME_NONE;
901 GST_BUFFER_DTS (buffer) = GST_CLOCK_TIME_NONE;
902 GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
903 GST_BUFFER_OFFSET (buffer) = GST_BUFFER_OFFSET_NONE;
904 GST_BUFFER_OFFSET_END (buffer) = GST_BUFFER_OFFSET_NONE;
906 /* remove all metadata without the POOLED flag */
907 gst_buffer_foreach_meta (buffer, remove_meta_unpooled, pool);
911 * gst_buffer_pool_acquire_buffer:
912 * @pool: a #GstBufferPool
913 * @buffer: (out): a location for a #GstBuffer
914 * @params: (transfer none) (allow-none) parameters.
916 * Acquire a buffer from @pool. @buffer should point to a memory location that
917 * can hold a pointer to the new buffer.
919 * @params can be NULL or contain optional parameters to influence the allocation.
921 * Returns: a #GstFlowReturn such as GST_FLOW_FLUSHING when the pool is
925 gst_buffer_pool_acquire_buffer (GstBufferPool * pool, GstBuffer ** buffer,
926 GstBufferPoolParams * params)
928 GstBufferPoolClass *pclass;
929 GstFlowReturn result;
931 g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), GST_FLOW_ERROR);
932 g_return_val_if_fail (buffer != NULL, GST_FLOW_ERROR);
934 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
936 /* assume we'll have one more outstanding buffer we need to do that so
937 * that concurrent set_active doesn't clear the buffers */
938 g_atomic_int_inc (&pool->priv->outstanding);
940 if (G_LIKELY (pclass->acquire_buffer))
941 result = pclass->acquire_buffer (pool, buffer, params);
943 result = GST_FLOW_NOT_SUPPORTED;
945 if (G_LIKELY (result == GST_FLOW_OK)) {
946 /* all buffers from the pool point to the pool and have the refcount of the
947 * pool incremented */
948 (*buffer)->pool = gst_object_ref (pool);
949 /* now reset the buffer when needed */
950 if (G_LIKELY (pclass->reset_buffer))
951 pclass->reset_buffer (pool, *buffer, params);
953 dec_outstanding (pool);
960 default_release_buffer (GstBufferPool * pool, GstBuffer * buffer)
962 /* keep it around in our queue */
963 GST_LOG_OBJECT (pool, "released buffer %p", buffer);
964 gst_atomic_queue_push (pool->priv->queue, buffer);
965 gst_poll_write_control (pool->priv->poll);
969 * gst_buffer_pool_release_buffer:
970 * @pool: a #GstBufferPool
971 * @buffer: (transfer none): a #GstBuffer
973 * Release @buffer to @pool. @buffer should have previously been allocated from
974 * @pool with gst_buffer_pool_acquire_buffer().
976 * This function is usually called automatically when the last ref on @buffer
980 gst_buffer_pool_release_buffer (GstBufferPool * pool, GstBuffer * buffer)
982 GstBufferPoolClass *pclass;
984 g_return_if_fail (GST_IS_BUFFER_POOL (pool));
985 g_return_if_fail (buffer != NULL);
987 /* check that the buffer is ours, all buffers returned to the pool have the
988 * pool member set to NULL and the pool refcount decreased */
989 if (!g_atomic_pointer_compare_and_exchange (&buffer->pool, pool, NULL))
992 pclass = GST_BUFFER_POOL_GET_CLASS (pool);
994 if (G_LIKELY (pclass->release_buffer))
995 pclass->release_buffer (pool, buffer);
997 dec_outstanding (pool);
999 /* decrease the refcount that the buffer had to us */
1000 gst_object_unref (pool);