/* GStreamer

 * Copyright (C) 2010 Wim Taymans <wim.taymans@gmail.com>

 *

 * gstbufferpool.c: GstBufferPool baseclass

 *

 * 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:gstbufferpool

 * @title: GstBufferPool

 * @short_description: Pool for buffers

 * @see_also: #GstBuffer

 *

 * A #GstBufferPool is an object that can be used to pre-allocate and recycle

 * buffers of the same size and with the same properties.

 *

 * A #GstBufferPool is created with gst_buffer_pool_new().

 *

 * Once a pool is created, it needs to be configured. A call to

 * gst_buffer_pool_get_config() returns the current configuration structure from

 * the pool. With gst_buffer_pool_config_set_params() and

 * gst_buffer_pool_config_set_allocator() the bufferpool parameters and

 * allocator can be configured. Other properties can be configured in the pool

 * depending on the pool implementation.

 *

 * A bufferpool can have extra options that can be enabled with

 * gst_buffer_pool_config_add_option(). The available options can be retrieved

 * with gst_buffer_pool_get_options(). Some options allow for additional

 * configuration properties to be set.

 *

 * After the configuration structure has been configured,

 * gst_buffer_pool_set_config() updates the configuration in the pool. This can

 * fail when the configuration structure is not accepted.

 *

 * After the a pool has been configured, it can be activated with

 * gst_buffer_pool_set_active(). This will preallocate the configured resources

 * in the pool.

 *

 * When the pool is active, gst_buffer_pool_acquire_buffer() can be used to

 * retrieve a buffer from the pool.

 *

 * Buffers allocated from a bufferpool will automatically be returned to the

 * pool with gst_buffer_pool_release_buffer() when their refcount drops to 0.

 *

 * The bufferpool can be deactivated again with gst_buffer_pool_set_active().

 * All further gst_buffer_pool_acquire_buffer() calls will return an error. When

 * all buffers are returned to the pool they will be freed.

 *

 * Use gst_object_unref() to release the reference to a bufferpool. If the

 * refcount of the pool reaches 0, the pool will be freed.

 */

#include "gst_private.h"

#include "glib-compat-private.h"

#include <errno.h>

#ifdef HAVE_UNISTD_H

#  include <unistd.h>

#endif

#include <sys/types.h>

#include "gstatomicqueue.h"

#include "gstpoll.h"

#include "gstinfo.h"

#include "gstquark.h"

#include "gstvalue.h"

#include "gstbufferpool.h"

#ifdef G_OS_WIN32

#  ifndef EWOULDBLOCK

#  define EWOULDBLOCK EAGAIN    /* This is just to placate gcc */

#  endif

#endif /* G_OS_WIN32 */

GST_DEBUG_CATEGORY_STATIC (gst_buffer_pool_debug);

#define GST_CAT_DEFAULT gst_buffer_pool_debug

#define GST_BUFFER_POOL_GET_PRIVATE(obj)  \

   (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BUFFER_POOL, GstBufferPoolPrivate))

#define GST_BUFFER_POOL_LOCK(pool)   (g_rec_mutex_lock(&pool->priv->rec_lock))

#define GST_BUFFER_POOL_UNLOCK(pool) (g_rec_mutex_unlock(&pool->priv->rec_lock))

struct _GstBufferPoolPrivate

{

  GstAtomicQueue *queue;

  GstPoll *poll;

  GRecMutex rec_lock;

  gboolean started;

  gboolean active;

  gint outstanding;             /* number of buffers that are in use */

  gboolean configured;

  GstStructure *config;

  guint size;

  guint min_buffers;

  guint max_buffers;

  guint cur_buffers;

  GstAllocator *allocator;

  GstAllocationParams params;

};

static void gst_buffer_pool_finalize (GObject * object);

G_DEFINE_TYPE (GstBufferPool, gst_buffer_pool, GST_TYPE_OBJECT);

static gboolean default_start (GstBufferPool * pool);

static gboolean default_stop (GstBufferPool * pool);

static gboolean default_set_config (GstBufferPool * pool,

    GstStructure * config);

static GstFlowReturn default_alloc_buffer (GstBufferPool * pool,

    GstBuffer ** buffer, GstBufferPoolAcquireParams * params);

static GstFlowReturn default_acquire_buffer (GstBufferPool * pool,

    GstBuffer ** buffer, GstBufferPoolAcquireParams * params);

static void default_reset_buffer (GstBufferPool * pool, GstBuffer * buffer);

static void default_free_buffer (GstBufferPool * pool, GstBuffer * buffer);

static void default_release_buffer (GstBufferPool * pool, GstBuffer * buffer);

static void

gst_buffer_pool_class_init (GstBufferPoolClass * klass)

{

  GObjectClass *gobject_class = (GObjectClass *) klass;

  g_type_class_add_private (klass, sizeof (GstBufferPoolPrivate));

  gobject_class->finalize = gst_buffer_pool_finalize;

  klass->start = default_start;

  klass->stop = default_stop;

  klass->set_config = default_set_config;

  klass->acquire_buffer = default_acquire_buffer;

  klass->reset_buffer = default_reset_buffer;

  klass->alloc_buffer = default_alloc_buffer;

  klass->release_buffer = default_release_buffer;

  klass->free_buffer = default_free_buffer;

  GST_DEBUG_CATEGORY_INIT (gst_buffer_pool_debug, "bufferpool", 0,

      "bufferpool debug");

}

static void

gst_buffer_pool_init (GstBufferPool * pool)

{

  GstBufferPoolPrivate *priv;

  priv = pool->priv = GST_BUFFER_POOL_GET_PRIVATE (pool);

  g_rec_mutex_init (&priv->rec_lock);

  priv->poll = gst_poll_new_timer ();

  priv->queue = gst_atomic_queue_new (16);

  pool->flushing = 1;

  priv->active = FALSE;

  priv->configured = FALSE;

  priv->started = FALSE;

  priv->config = gst_structure_new_id_empty (GST_QUARK (BUFFER_POOL_CONFIG));

  gst_buffer_pool_config_set_params (priv->config, NULL, 0, 0, 0);

  priv->allocator = NULL;

  gst_allocation_params_init (&priv->params);

  gst_buffer_pool_config_set_allocator (priv->config, priv->allocator,

      &priv->params);

  /* 1 control write for flushing - the flush token */

  gst_poll_write_control (priv->poll);

  /* 1 control write for marking that we are not waiting for poll - the wait token */

  gst_poll_write_control (priv->poll);

  GST_DEBUG_OBJECT (pool, "created");

}

static void

gst_buffer_pool_finalize (GObject * object)

{

  GstBufferPool *pool;

  GstBufferPoolPrivate *priv;

  pool = GST_BUFFER_POOL_CAST (object);

  priv = pool->priv;

  GST_DEBUG_OBJECT (pool, "%p finalize", pool);

  gst_buffer_pool_set_active (pool, FALSE);

  gst_atomic_queue_unref (priv->queue);

  gst_poll_free (priv->poll);

  gst_structure_free (priv->config);

  g_rec_mutex_clear (&priv->rec_lock);

  if (priv->allocator)

    gst_object_unref (priv->allocator);

  G_OBJECT_CLASS (gst_buffer_pool_parent_class)->finalize (object);

}

/**

 * gst_buffer_pool_new:

 *

 * Creates a new #GstBufferPool instance.

 *

 * Returns: (transfer full): a new #GstBufferPool instance

 */

GstBufferPool *

gst_buffer_pool_new (void)

{

  GstBufferPool *result;

  result = g_object_new (GST_TYPE_BUFFER_POOL, NULL);

  GST_DEBUG_OBJECT (result, "created new buffer pool");

  /* Clear floating flag */

  gst_object_ref_sink (result);

  return result;

}

static GstFlowReturn

default_alloc_buffer (GstBufferPool * pool, GstBuffer ** buffer,

    GstBufferPoolAcquireParams * params)

{

  GstBufferPoolPrivate *priv = pool->priv;

  *buffer =

      gst_buffer_new_allocate (priv->allocator, priv->size, &priv->params);

  if (!*buffer)

    return GST_FLOW_ERROR;

  return GST_FLOW_OK;

}

static gboolean

mark_meta_pooled (GstBuffer * buffer, GstMeta ** meta, gpointer user_data)

{

  GST_DEBUG_OBJECT (GST_BUFFER_POOL (user_data),

      "marking meta %p as POOLED in buffer %p", *meta, buffer);

  GST_META_FLAG_SET (*meta, GST_META_FLAG_POOLED);

  GST_META_FLAG_SET (*meta, GST_META_FLAG_LOCKED);

  return TRUE;

}

static GstFlowReturn

do_alloc_buffer (GstBufferPool * pool, GstBuffer ** buffer,

    GstBufferPoolAcquireParams * params)

{

  GstBufferPoolPrivate *priv = pool->priv;

  GstFlowReturn result;

  gint cur_buffers, max_buffers;

  GstBufferPoolClass *pclass;

  pclass = GST_BUFFER_POOL_GET_CLASS (pool);

  if (G_UNLIKELY (!pclass->alloc_buffer))

    goto no_function;

  max_buffers = priv->max_buffers;

  /* increment the allocation counter */

  cur_buffers = g_atomic_int_add (&priv->cur_buffers, 1);

  if (max_buffers && cur_buffers >= max_buffers)

    goto max_reached;

  result = pclass->alloc_buffer (pool, buffer, params);

  if (G_UNLIKELY (result != GST_FLOW_OK))

    goto alloc_failed;

  /* lock all metadata and mark as pooled, we want this to remain on

   * the buffer and we want to remove any other metadata that gets added

   * later */

  gst_buffer_foreach_meta (*buffer, mark_meta_pooled, pool);

  /* un-tag memory, this is how we expect the buffer when it is

   * released again */

  GST_BUFFER_FLAG_UNSET (*buffer, GST_BUFFER_FLAG_TAG_MEMORY);

  GST_LOG_OBJECT (pool, "allocated buffer %d/%d, %p", cur_buffers,

      max_buffers, *buffer);

  return result;

  /* ERRORS */

no_function:

  {

    GST_ERROR_OBJECT (pool, "no alloc function");

    return GST_FLOW_NOT_SUPPORTED;

  }

max_reached:

  {

    GST_DEBUG_OBJECT (pool, "max buffers reached");

    g_atomic_int_add (&priv->cur_buffers, -1);

    return GST_FLOW_EOS;

  }

alloc_failed:

  {

    GST_WARNING_OBJECT (pool, "alloc function failed");

    g_atomic_int_add (&priv->cur_buffers, -1);

    return result;

  }

}

/* the default implementation for preallocating the buffers in the pool */

static gboolean

default_start (GstBufferPool * pool)

{

  guint i;

  GstBufferPoolPrivate *priv = pool->priv;

  GstBufferPoolClass *pclass;

  pclass = GST_BUFFER_POOL_GET_CLASS (pool);

  /* we need to prealloc buffers */

  for (i = 0; i < priv->min_buffers; i++) {

    GstBuffer *buffer;

    if (do_alloc_buffer (pool, &buffer, NULL) != GST_FLOW_OK)

      goto alloc_failed;

    /* release to the queue, we call the vmethod directly, we don't need to do

     * the other refcount handling right now. */

    if (G_LIKELY (pclass->release_buffer))

      pclass->release_buffer (pool, buffer);

  }

  return TRUE;

  /* ERRORS */

alloc_failed:

  {

    GST_WARNING_OBJECT (pool, "failed to allocate buffer");

    return FALSE;

  }

}

/* must be called with the lock */

static gboolean

do_start (GstBufferPool * pool)

{

  GstBufferPoolPrivate *priv = pool->priv;

  if (!priv->started) {

    GstBufferPoolClass *pclass;

    pclass = GST_BUFFER_POOL_GET_CLASS (pool);

    GST_LOG_OBJECT (pool, "starting");

    /* start the pool, subclasses should allocate buffers and put them

     * in the queue */

    if (G_LIKELY (pclass->start)) {

      if (!pclass->start (pool))

        return FALSE;

    }

    priv->started = TRUE;

  }

  return TRUE;

}

static void

default_free_buffer (GstBufferPool * pool, GstBuffer * buffer)

{

  gst_buffer_unref (buffer);

}

static void

do_free_buffer (GstBufferPool * pool, GstBuffer * buffer)

{

  GstBufferPoolPrivate *priv;

  GstBufferPoolClass *pclass;

  priv = pool->priv;

  pclass = GST_BUFFER_POOL_GET_CLASS (pool);

  g_atomic_int_add (&priv->cur_buffers, -1);

  GST_LOG_OBJECT (pool, "freeing buffer %p (%u left)", buffer,

      priv->cur_buffers);

  if (G_LIKELY (pclass->free_buffer))

    pclass->free_buffer (pool, buffer);

}

/* must be called with the lock */

static gboolean

default_stop (GstBufferPool * pool)

{

  GstBufferPoolPrivate *priv = pool->priv;

  GstBuffer *buffer;

  /* clear the pool */

  while ((buffer = gst_atomic_queue_pop (priv->queue))) {

    while (!gst_poll_read_control (priv->poll)) {

      if (errno == EWOULDBLOCK) {

        /* We put the buffer into the queue but did not finish writing control

         * yet, let's wait a bit and retry */

        g_thread_yield ();

        continue;

      } else {

        /* Critical error but GstPoll already complained */

        break;

      }

    }

    do_free_buffer (pool, buffer);

  }

  return priv->cur_buffers == 0;

}

/* must be called with the lock */

static gboolean

do_stop (GstBufferPool * pool)

{

  GstBufferPoolPrivate *priv = pool->priv;

  if (priv->started) {

    GstBufferPoolClass *pclass;

    pclass = GST_BUFFER_POOL_GET_CLASS (pool);

    GST_LOG_OBJECT (pool, "stopping");

    if (G_LIKELY (pclass->stop)) {

      if (!pclass->stop (pool))

        return FALSE;

    }

    priv->started = FALSE;

  }

  return TRUE;

}

/* must be called with the lock */

static void

do_set_flushing (GstBufferPool * pool, gboolean flushing)

{

  GstBufferPoolPrivate *priv = pool->priv;

  GstBufferPoolClass *pclass;

  pclass = GST_BUFFER_POOL_GET_CLASS (pool);

  if (GST_BUFFER_POOL_IS_FLUSHING (pool) == flushing)

    return;

  if (flushing) {

    g_atomic_int_set (&pool->flushing, 1);

    /* Write the flush token to wake up any waiters */

    gst_poll_write_control (priv->poll);

    if (pclass->flush_start)

      pclass->flush_start (pool);

  } else {

    if (pclass->flush_stop)

      pclass->flush_stop (pool);

    while (!gst_poll_read_control (priv->poll)) {

      if (errno == EWOULDBLOCK) {

        /* This should not really happen unless flushing and unflushing

         * happens on different threads. Let's wait a bit to get back flush

         * token from the thread that was setting it to flushing */

        g_thread_yield ();

        continue;

      } else {

        /* Critical error but GstPoll already complained */

        break;

      }

    }

    g_atomic_int_set (&pool->flushing, 0);

  }

}

/**

 * gst_buffer_pool_set_active:

 * @pool: a #GstBufferPool

 * @active: the new active state

 *

 * Control the active state of @pool. When the pool is inactive, new calls to

 * gst_buffer_pool_acquire_buffer() will return with %GST_FLOW_FLUSHING.

 *

 * Activating the bufferpool will preallocate all resources in the pool based on

 * the configuration of the pool.

 *

 * Deactivating will free the resources again when there are no outstanding

 * buffers. When there are outstanding buffers, they will be freed as soon as

 * they are all returned to the pool.

 *

 * Returns: %FALSE when the pool was not configured or when preallocation of the

 * buffers failed.

 */

gboolean

gst_buffer_pool_set_active (GstBufferPool * pool, gboolean active)

{

  gboolean res = TRUE;

  GstBufferPoolPrivate *priv;

  g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), FALSE);

  GST_LOG_OBJECT (pool, "active %d", active);

  priv = pool->priv;

  GST_BUFFER_POOL_LOCK (pool);

  /* just return if we are already in the right state */

  if (priv->active == active)

    goto was_ok;

  /* we need to be configured */

  if (!priv->configured)

    goto not_configured;

  if (active) {

    if (!do_start (pool))

      goto start_failed;

    /* flush_stop my release buffers, setting to active to avoid running

     * do_stop while activating the pool */

    priv->active = TRUE;

    /* unset the flushing state now */

    do_set_flushing (pool, FALSE);

  } else {

    gint outstanding;

    /* set to flushing first */

    do_set_flushing (pool, TRUE);

    /* when all buffers are in the pool, free them. Else they will be

     * freed when they are released */

    outstanding = g_atomic_int_get (&priv->outstanding);

    GST_LOG_OBJECT (pool, "outstanding buffers %d", outstanding);

    if (outstanding == 0) {

      if (!do_stop (pool))

        goto stop_failed;

    }

    priv->active = FALSE;

  }

  GST_BUFFER_POOL_UNLOCK (pool);

  return res;

was_ok:

  {

    GST_DEBUG_OBJECT (pool, "pool was in the right state");

    GST_BUFFER_POOL_UNLOCK (pool);

    return TRUE;

  }

not_configured:

  {

    GST_ERROR_OBJECT (pool, "pool was not configured");

    GST_BUFFER_POOL_UNLOCK (pool);

    return FALSE;

  }

start_failed:

  {

    GST_ERROR_OBJECT (pool, "start failed");

    GST_BUFFER_POOL_UNLOCK (pool);

    return FALSE;

  }

stop_failed:

  {

    GST_WARNING_OBJECT (pool, "stop failed");

    GST_BUFFER_POOL_UNLOCK (pool);

    return FALSE;

  }

}

/**

 * gst_buffer_pool_is_active:

 * @pool: a #GstBufferPool

 *

 * Check if @pool is active. A pool can be activated with the

 * gst_buffer_pool_set_active() call.

 *

 * Returns: %TRUE when the pool is active.

 */

gboolean

gst_buffer_pool_is_active (GstBufferPool * pool)

{

  gboolean res;

  GST_BUFFER_POOL_LOCK (pool);

  res = pool->priv->active;

  GST_BUFFER_POOL_UNLOCK (pool);

  return res;

}

static gboolean

default_set_config (GstBufferPool * pool, GstStructure * config)

{

  GstBufferPoolPrivate *priv = pool->priv;

  GstCaps *caps;

  guint size, min_buffers, max_buffers;

  GstAllocator *allocator;

  GstAllocationParams params;

  /* parse the config and keep around */

  if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers,

          &max_buffers))

    goto wrong_config;

  if (!gst_buffer_pool_config_get_allocator (config, &allocator, &params))

    goto wrong_config;

  GST_DEBUG_OBJECT (pool, "config %" GST_PTR_FORMAT, config);

  priv->size = size;

  priv->min_buffers = min_buffers;

  priv->max_buffers = max_buffers;

  priv->cur_buffers = 0;

  if (priv->allocator)

    gst_object_unref (priv->allocator);

  if ((priv->allocator = allocator))

    gst_object_ref (allocator);

  priv->params = params;

  return TRUE;

wrong_config:

  {

    GST_WARNING_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config);

    return FALSE;

  }

}

/**

 * gst_buffer_pool_set_config:

 * @pool: a #GstBufferPool

 * @config: (transfer full): a #GstStructure

 *

 * Set the configuration of the pool. If the pool is already configured, and

 * the configuration haven't change, this function will return %TRUE. If the

 * pool is active, this method will return %FALSE and active configuration

 * will remain. Buffers allocated form this pool must be returned or else this

 * function will do nothing and return %FALSE.

 *

 * @config is a #GstStructure that contains the configuration parameters for

 * the pool. A default and mandatory set of parameters can be configured with

 * gst_buffer_pool_config_set_params(), gst_buffer_pool_config_set_allocator()

 * and gst_buffer_pool_config_add_option().

 *

 * If the parameters in @config can not be set exactly, this function returns

 * %FALSE and will try to update as much state as possible. The new state can

 * then be retrieved and refined with gst_buffer_pool_get_config().

 *

 * This function takes ownership of @config.

 *

 * Returns: %TRUE when the configuration could be set.

 */

gboolean

gst_buffer_pool_set_config (GstBufferPool * pool, GstStructure * config)

{

  gboolean result;

  GstBufferPoolClass *pclass;

  GstBufferPoolPrivate *priv;

  g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), FALSE);

  g_return_val_if_fail (config != NULL, FALSE);

  priv = pool->priv;

  GST_BUFFER_POOL_LOCK (pool);

  /* nothing to do if config is unchanged */

  if (priv->configured && gst_structure_is_equal (config, priv->config))

    goto config_unchanged;

  /* can't change the settings when active */

  if (priv->active)

    goto was_active;

  /* we can't change when outstanding buffers */

  if (g_atomic_int_get (&priv->outstanding) != 0)

    goto have_outstanding;

  pclass = GST_BUFFER_POOL_GET_CLASS (pool);

  /* set the new config */

  if (G_LIKELY (pclass->set_config))

    result = pclass->set_config (pool, config);

  else

    result = FALSE;

  /* save the config regardless of the result so user can read back the

   * modified config and evaluate if the changes are acceptable */

  if (priv->config)

    gst_structure_free (priv->config);

  priv->config = config;

  if (result) {

    /* now we are configured */

    priv->configured = TRUE;

  }

  GST_BUFFER_POOL_UNLOCK (pool);

  return result;

config_unchanged:

  {

    gst_structure_free (config);

    GST_BUFFER_POOL_UNLOCK (pool);

    return TRUE;

  }

  /* ERRORS */

was_active:

  {

    gst_structure_free (config);

    GST_INFO_OBJECT (pool, "can't change config, we are active");

    GST_BUFFER_POOL_UNLOCK (pool);

    return FALSE;

  }

have_outstanding:

  {

    gst_structure_free (config);

    GST_WARNING_OBJECT (pool, "can't change config, have outstanding buffers");

    GST_BUFFER_POOL_UNLOCK (pool);

    return FALSE;

  }

}

/**

 * gst_buffer_pool_get_config:

 * @pool: a #GstBufferPool

 *

 * Get a copy of the current configuration of the pool. This configuration

 * can either be modified and used for the gst_buffer_pool_set_config() call

 * or it must be freed after usage.

 *

 * Returns: (transfer full): a copy of the current configuration of @pool. use

 * gst_structure_free() after usage or gst_buffer_pool_set_config().

 */

GstStructure *

gst_buffer_pool_get_config (GstBufferPool * pool)

{

  GstStructure *result;

  g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), NULL);

  GST_BUFFER_POOL_LOCK (pool);

  result = gst_structure_copy (pool->priv->config);

  GST_BUFFER_POOL_UNLOCK (pool);

  return result;

}

static const gchar *empty_option[] = { NULL };

/**

 * gst_buffer_pool_get_options:

 * @pool: a #GstBufferPool

 *

 * Get a %NULL terminated array of string with supported bufferpool options for

 * @pool. An option would typically be enabled with

 * gst_buffer_pool_config_add_option().

 *

 * Returns: (array zero-terminated=1) (transfer none): a %NULL terminated array

 *          of strings.

 */

const gchar **

gst_buffer_pool_get_options (GstBufferPool * pool)

{

  GstBufferPoolClass *pclass;

  const gchar **result;

  g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), NULL);

  pclass = GST_BUFFER_POOL_GET_CLASS (pool);

  if (G_LIKELY (pclass->get_options)) {

    if ((result = pclass->get_options (pool)) == NULL)

      goto invalid_result;

  } else

    result = empty_option;

  return result;

  /* ERROR */

invalid_result:

  {

    g_warning ("bufferpool subclass returned NULL options");

    return empty_option;

  }

}

/**

 * gst_buffer_pool_has_option:

 * @pool: a #GstBufferPool

 * @option: an option

 *

 * Check if the bufferpool supports @option.

 *

 * Returns: %TRUE if the buffer pool contains @option.

 */

gboolean

gst_buffer_pool_has_option (GstBufferPool * pool, const gchar * option)

{

  guint i;

  const gchar **options;

  g_return_val_if_fail (GST_IS_BUFFER_POOL (pool), FALSE);

  g_return_val_if_fail (option != NULL, FALSE);

  options = gst_buffer_pool_get_options (pool);

  for (i = 0; options[i]; i++) {

    if (g_str_equal (options[i], option))

      return TRUE;

  }

  return FALSE;

}

/**

 * gst_buffer_pool_config_set_params:

 * @config: a #GstBufferPool configuration

 * @caps: caps for the buffers

 * @size: the size of each buffer, not including prefix and padding

 * @min_buffers: the minimum amount of buffers to allocate.

 * @max_buffers: the maximum amount of buffers to allocate or 0 for unlimited.

 *

 * Configure @config with the given parameters.

 */

void

gst_buffer_pool_config_set_params (GstStructure * config, GstCaps * caps,

    guint size, guint min_buffers, guint max_buffers)

{

  g_return_if_fail (config != NULL);

  g_return_if_fail (max_buffers == 0 || min_buffers <= max_buffers);

  g_return_if_fail (caps == NULL || gst_caps_is_fixed (caps));

  gst_structure_id_set (config,

      GST_QUARK (CAPS), GST_TYPE_CAPS, caps,

      GST_QUARK (SIZE), G_TYPE_UINT, size,

      GST_QUARK (MIN_BUFFERS), G_TYPE_UINT, min_buffers,

      GST_QUARK (MAX_BUFFERS), G_TYPE_UINT, max_buffers, NULL);

}

/**

 * gst_buffer_pool_config_set_allocator:

 * @config: a #GstBufferPool configuration

 * @allocator: (allow-none): a #GstAllocator

 * @params: (allow-none): #GstAllocationParams

 *

 * Set the @allocator and @params on @config.

 *

 * One of @allocator and @params can be %NULL, but not both. When @allocator

 * is %NULL, the default allocator of the pool will use the values in @param

 * to perform its allocation. When @param is %NULL, the pool will use the

 * provided @allocator with its default #GstAllocationParams.

 *

 * A call to gst_buffer_pool_set_config() can update the allocator and params

 * with the values that it is able to do. Some pools are, for example, not able

 * to operate with different allocators or cannot allocate with the values

 * specified in @params. Use gst_buffer_pool_get_config() to get the currently

 * used values.

 */

void

gst_buffer_pool_config_set_allocator (GstStructure * config,

    GstAllocator * allocator, const GstAllocationParams * params)

{

  g_return_if_fail (config != NULL);

  g_return_if_fail (allocator != NULL || params != NULL);

  gst_structure_id_set (config,

      GST_QUARK (ALLOCATOR), GST_TYPE_ALLOCATOR, allocator,

      GST_QUARK (PARAMS), GST_TYPE_ALLOCATION_PARAMS, params, NULL);

}

/**

 * gst_buffer_pool_config_add_option:

 * @config: a #GstBufferPool configuration