/**
* SECTION:gstbufferpool
+ * @title: GstBufferPool
* @short_description: Pool for buffers
* @see_also: #GstBuffer
*
*
* Use gst_object_unref() to release the reference to a bufferpool. If the
* refcount of the pool reaches 0, the pool will be freed.
- *
- * Last reviewed on 2014-01-30 (1.3.0)
*/
#include "gst_private.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))
static void gst_buffer_pool_finalize (GObject * object);
-G_DEFINE_TYPE (GstBufferPool, gst_buffer_pool, GST_TYPE_OBJECT);
+G_DEFINE_TYPE_WITH_PRIVATE (GstBufferPool, gst_buffer_pool, GST_TYPE_OBJECT);
static gboolean default_start (GstBufferPool * pool);
static gboolean default_stop (GstBufferPool * pool);
{
GObjectClass *gobject_class = (GObjectClass *) klass;
- g_type_class_add_private (klass, sizeof (GstBufferPoolPrivate));
-
gobject_class->finalize = gst_buffer_pool_finalize;
klass->start = default_start;
{
GstBufferPoolPrivate *priv;
- priv = pool->priv = GST_BUFFER_POOL_GET_PRIVATE (pool);
+ priv = pool->priv = gst_buffer_pool_get_instance_private (pool);
g_rec_mutex_init (&priv->rec_lock);
gst_allocation_params_init (&priv->params);
gst_buffer_pool_config_set_allocator (priv->config, priv->allocator,
&priv->params);
- /* 1 control write for flushing */
+ /* 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 */
+ /* 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");
pool = GST_BUFFER_POOL_CAST (object);
priv = pool->priv;
- GST_DEBUG_OBJECT (pool, "finalize");
+ GST_DEBUG_OBJECT (pool, "%p finalize", pool);
gst_buffer_pool_set_active (pool, FALSE);
gst_atomic_queue_unref (priv->queue);
{
GstBufferPool *result;
- result = g_object_newv (GST_TYPE_BUFFER_POOL, 0, NULL);
+ 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;
}
*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)
{
- GstBufferPool *pool = user_data;
-
- GST_DEBUG_OBJECT (pool, "marking meta %p as POOLED in buffer %p", *meta,
- buffer);
+ 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);
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);
+ max_buffers, *buffer);
return result;
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;
- GstBufferPoolClass *pclass;
-
- pclass = GST_BUFFER_POOL_GET_CLASS (pool);
/* clear the pool */
while ((buffer = gst_atomic_queue_pop (priv->queue))) {
- GST_LOG_OBJECT (pool, "freeing buffer %p", buffer);
- gst_poll_read_control (priv->poll);
-
- if (G_LIKELY (pclass->free_buffer))
- pclass->free_buffer (pool, buffer);
+ 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);
}
- priv->cur_buffers = 0;
-
- return TRUE;
+ return priv->cur_buffers == 0;
}
/* must be called with the lock */
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
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 */
- gst_poll_read_control (priv->poll);
- g_atomic_int_set (&pool->flushing, 0);
+ do_set_flushing (pool, FALSE);
} else {
gint outstanding;
/* set to flushing first */
- g_atomic_int_set (&pool->flushing, 1);
- gst_poll_write_control (priv->poll);
+ do_set_flushing (pool, TRUE);
/* when all buffers are in the pool, free them. Else they will be
* freed when they are released */
if (!do_stop (pool))
goto stop_failed;
}
+
+ priv->active = FALSE;
}
- priv->active = active;
GST_BUFFER_POOL_UNLOCK (pool);
return res;
* @pool: a #GstBufferPool
* @config: (transfer full): a #GstStructure
*
- * Set the configuration of the pool. The pool must be inactive and all buffers
- * allocated form this pool must be returned or else this function will do
- * nothing and return FALSE.
+ * 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
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;
else
result = FALSE;
- if (result) {
- if (priv->config)
- gst_structure_free (priv->config);
- priv->config = config;
+ /* 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;
- } else {
- gst_structure_free (config);
}
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_WARNING_OBJECT (pool, "can't change config, we are active");
+ GST_INFO_OBJECT (pool, "can't change config, we are active");
GST_BUFFER_POOL_UNLOCK (pool);
return FALSE;
}
*
* Check if the bufferpool supports @option.
*
- * Returns: a %NULL terminated array of strings.
+ * Returns: %TRUE if the buffer pool contains @option.
*/
gboolean
gst_buffer_pool_has_option (GstBufferPool * pool, const gchar * option)
/**
* gst_buffer_pool_config_set_allocator:
* @config: a #GstBufferPool configuration
- * @allocator: a #GstAllocator
- * @params: #GstAllocationParams
+ * @allocator: (allow-none): a #GstAllocator
+ * @params: (allow-none): #GstAllocationParams
*
* Set the @allocator and @params on @config.
*
/**
* gst_buffer_pool_config_get_allocator:
* @config: (transfer none): a #GstBufferPool configuration
- * @allocator: (transfer none): a #GstAllocator
- * @params: #GstAllocationParams
+ * @allocator: (out) (allow-none) (transfer none): a #GstAllocator, or %NULL
+ * @params: (out) (allow-none): #GstAllocationParams, or %NULL
*
* Get the @allocator and @params from @config.
*
- * Returns: %TRUE, if the values are set.
+ * Returns: %TRUE, if the values are set.
*/
gboolean
gst_buffer_pool_config_get_allocator (GstStructure * config,
return TRUE;
}
+/**
+ * gst_buffer_pool_config_validate_params:
+ * @config: (transfer none): a #GstBufferPool configuration
+ * @caps: (transfer none): the excepted caps of buffers
+ * @size: the expected size of each buffer, not including prefix and padding
+ * @min_buffers: the expected minimum amount of buffers to allocate.
+ * @max_buffers: the expect maximum amount of buffers to allocate or 0 for unlimited.
+ *
+ * Validate that changes made to @config are still valid in the context of the
+ * expected parameters. This function is a helper that can be used to validate
+ * changes made by a pool to a config when gst_buffer_pool_set_config()
+ * returns %FALSE. This expects that @caps haven't changed and that
+ * @min_buffers aren't lower then what we initially expected.
+ * This does not check if options or allocator parameters are still valid,
+ * won't check if size have changed, since changing the size is valid to adapt
+ * padding.
+ *
+ * Since: 1.4
+ *
+ * Returns: %TRUE, if the parameters are valid in this context.
+ */
+gboolean
+gst_buffer_pool_config_validate_params (GstStructure * config, GstCaps * caps,
+ guint size, guint min_buffers, G_GNUC_UNUSED guint max_buffers)
+{
+ GstCaps *newcaps;
+ guint newsize, newmin;
+ gboolean ret = FALSE;
+
+ g_return_val_if_fail (config != NULL, FALSE);
+
+ gst_buffer_pool_config_get_params (config, &newcaps, &newsize, &newmin, NULL);
+
+ if (gst_caps_is_equal (caps, newcaps) && (newsize >= size)
+ && (newmin >= min_buffers))
+ ret = TRUE;
+
+ return ret;
+}
+
static GstFlowReturn
default_acquire_buffer (GstBufferPool * pool, GstBuffer ** buffer,
GstBufferPoolAcquireParams * params)
/* try to get a buffer from the queue */
*buffer = gst_atomic_queue_pop (priv->queue);
if (G_LIKELY (*buffer)) {
- gst_poll_read_control (priv->poll);
+ 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;
+ }
+ }
result = GST_FLOW_OK;
GST_LOG_OBJECT (pool, "acquired buffer %p", *buffer);
break;
/* no buffer, try to allocate some more */
GST_LOG_OBJECT (pool, "no buffer, trying to allocate");
- result = do_alloc_buffer (pool, buffer, NULL);
+ result = do_alloc_buffer (pool, buffer, params);
if (G_LIKELY (result == GST_FLOW_OK))
/* we have a buffer, return it */
break;
/* now we release the control socket, we wait for a buffer release or
* flushing */
- gst_poll_read_control (pool->priv->poll);
- GST_LOG_OBJECT (pool, "waiting for free buffers or flushing");
- gst_poll_wait (priv->poll, GST_CLOCK_TIME_NONE);
- gst_poll_write_control (pool->priv->poll);
+ if (!gst_poll_read_control (pool->priv->poll)) {
+ if (errno == EWOULDBLOCK) {
+ /* This means that we have two threads trying to allocate buffers
+ * already, and the other one already got the wait token. This
+ * means that we only have to wait for the poll now and not write the
+ * token afterwards: we will be woken up once the other thread is
+ * woken up and that one will write the wait token it removed */
+ GST_LOG_OBJECT (pool, "waiting for free buffers or flushing");
+ gst_poll_wait (priv->poll, GST_CLOCK_TIME_NONE);
+ } else {
+ /* This is a critical error, GstPoll already gave a warning */
+ result = GST_FLOW_ERROR;
+ break;
+ }
+ } else {
+ /* We're the first thread waiting, we got the wait token and have to
+ * write it again later
+ * OR
+ * We're a second thread and just consumed the flush token and block all
+ * other threads, in which case we must not wait and give it back
+ * immediately */
+ if (!GST_BUFFER_POOL_IS_FLUSHING (pool)) {
+ GST_LOG_OBJECT (pool, "waiting for free buffers or flushing");
+ gst_poll_wait (priv->poll, GST_CLOCK_TIME_NONE);
+ }
+ gst_poll_write_control (pool->priv->poll);
+ }
}
return result;
if (GST_BUFFER_POOL_IS_FLUSHING (pool)) {
/* take the lock so that set_active is not run concurrently */
GST_BUFFER_POOL_LOCK (pool);
- /* recheck the flushing state in the lock, the pool could have been
- * set to active again */
- if (GST_BUFFER_POOL_IS_FLUSHING (pool))
+ /* now that we have the lock, check if we have been de-activated with
+ * outstanding buffers */
+ if (!pool->priv->active)
do_stop (pool);
GST_BUFFER_POOL_UNLOCK (pool);
static void
default_reset_buffer (GstBufferPool * pool, GstBuffer * buffer)
{
- GST_BUFFER_FLAGS (buffer) = 0;
+ GST_BUFFER_FLAGS (buffer) &= GST_BUFFER_FLAG_TAG_MEMORY;
GST_BUFFER_PTS (buffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DTS (buffer) = GST_CLOCK_TIME_NONE;
GST_BUFFER_OFFSET (buffer) = GST_BUFFER_OFFSET_NONE;
GST_BUFFER_OFFSET_END (buffer) = GST_BUFFER_OFFSET_NONE;
+ /* if the memory is intact reset the size to the full size */
+ if (!GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY))
+ gst_buffer_resize (buffer, 0, pool->priv->size);
+
/* remove all metadata without the POOLED flag */
gst_buffer_foreach_meta (buffer, remove_meta_unpooled, pool);
}
* gst_buffer_pool_acquire_buffer:
* @pool: a #GstBufferPool
* @buffer: (out): a location for a #GstBuffer
- * @params: (transfer none) (allow-none) parameters.
+ * @params: (transfer none) (allow-none): parameters.
*
* Acquire a buffer from @pool. @buffer should point to a memory location that
* can hold a pointer to the new buffer.
static void
default_release_buffer (GstBufferPool * pool, GstBuffer * buffer)
{
+ GST_LOG_OBJECT (pool, "released buffer %p %d", buffer,
+ GST_MINI_OBJECT_FLAGS (buffer));
+
+ /* memory should be untouched */
+ if (G_UNLIKELY (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY)))
+ goto memory_tagged;
+
+ /* size should have been reset. This is not a catch all, pool with
+ * size requirement per memory should do their own check. */
+ if (G_UNLIKELY (gst_buffer_get_size (buffer) != pool->priv->size))
+ goto size_changed;
+
+ /* all memory should be exclusive to this buffer (and thus be writable) */
+ if (G_UNLIKELY (!gst_buffer_is_all_memory_writable (buffer)))
+ goto not_writable;
+
/* keep it around in our queue */
- GST_LOG_OBJECT (pool, "released buffer %p", buffer);
gst_atomic_queue_push (pool->priv->queue, buffer);
gst_poll_write_control (pool->priv->poll);
+
+ return;
+
+memory_tagged:
+ {
+ GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, pool,
+ "discarding buffer %p: memory tag set", buffer);
+ goto discard;
+ }
+size_changed:
+ {
+ GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, pool,
+ "discarding buffer %p: size %" G_GSIZE_FORMAT " != %u",
+ buffer, gst_buffer_get_size (buffer), pool->priv->size);
+ goto discard;
+ }
+not_writable:
+ {
+ GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, pool,
+ "discarding buffer %p: memory not writable", buffer);
+ goto discard;
+ }
+discard:
+ {
+ do_free_buffer (pool, buffer);
+ return;
+ }
}
/**
/* decrease the refcount that the buffer had to us */
gst_object_unref (pool);
}
+
+/**
+ * gst_buffer_pool_set_flushing:
+ * @pool: a #GstBufferPool
+ * @flushing: whether to start or stop flushing
+ *
+ * Enable or disable the flushing state of a @pool without freeing or
+ * allocating buffers.
+ *
+ * Since: 1.4
+ */
+void
+gst_buffer_pool_set_flushing (GstBufferPool * pool, gboolean flushing)
+{
+ GstBufferPoolPrivate *priv;
+
+ g_return_if_fail (GST_IS_BUFFER_POOL (pool));
+
+ GST_LOG_OBJECT (pool, "flushing %d", flushing);
+
+ priv = pool->priv;
+
+ GST_BUFFER_POOL_LOCK (pool);
+
+ if (!priv->active) {
+ GST_WARNING_OBJECT (pool, "can't change flushing state of inactive pool");
+ goto done;
+ }
+
+ do_set_flushing (pool, flushing);
+
+done:
+ GST_BUFFER_POOL_UNLOCK (pool);
+}
projects / platform / upstream / gstreamer.git / blobdiff