/**
* SECTION:gstbufferpool
+ * @title: GstBufferPool
* @short_description: Pool for buffers
* @see_also: #GstBuffer
*
#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
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);
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);
/* clear the pool */
while ((buffer = gst_atomic_queue_pop (priv->queue))) {
- 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;
+ }
+ }
do_free_buffer (pool, buffer);
}
return priv->cur_buffers == 0;
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)
if (pclass->flush_stop)
pclass->flush_stop (pool);
- gst_poll_read_control (priv->poll);
+ 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_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,
/* 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;