/**
* gst_task_join:
* @task: The #GstTask to join
*
* Joins @task. After this call, it is safe to unref the task
* and clean up the lock set with gst_task_set_lock().
*
* The task will automatically be stopped with this call.
*
* This function cannot be called from within a task function as this
* would cause a deadlock. The function will detect this and print a
* g_warning.
*
* Returns: %TRUE if the task could be joined.
*
* MT safe.
*/
gboolean
gst_task_join (GstTask * task)
{
GThread *tself;
GstTaskPrivate *priv;
gpointer id;
GstTaskPool *pool = NULL;
priv = task->priv;
g_return_val_if_fail (GST_IS_TASK (task), FALSE);
tself = g_thread_self ();
GST_DEBUG_OBJECT (task, "Joining task %p, thread %p", task, tself);
/* we don't use a real thread join here because we are using
* thread pools */
GST_OBJECT_LOCK (task);
if (G_UNLIKELY (tself == task->abidata.ABI.thread))
goto joining_self;
task->state = GST_TASK_STOPPED;
/* signal the state change for when it was blocked in PAUSED. */
GST_TASK_SIGNAL (task);
/* we set the running flag when pushing the task on the thread pool.
* This means that the task function might not be called when we try
* to join it here. */
while (G_LIKELY (task->running))
GST_TASK_WAIT (task);
/* clean the thread */
task->abidata.ABI.thread = NULL;
/* get the id and pool to join */
pool = priv->pool_id;
id = priv->id;
priv->pool_id = NULL;
priv->id = NULL;
GST_OBJECT_UNLOCK (task);
if (pool) {
if (id)
gst_task_pool_join (pool, id);
gst_object_unref (pool);
}
GST_DEBUG_OBJECT (task, "Joined task %p", task);
return TRUE;
/* ERRORS */
joining_self:
{
GST_WARNING_OBJECT (task, "trying to join task from its thread");
GST_OBJECT_UNLOCK (task);
g_warning ("\nTrying to join task %p from its thread would deadlock.\n"
"You cannot change the state of an element from its streaming\n"
"thread. Use g_idle_add() or post a GstMessage on the bus to\n"
"schedule the state change from the main thread.\n", task);
return FALSE;
}
}
static GstFlowReturn
gst_v4l2_video_dec_finish (GstVideoDecoder * decoder)
{
GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
GstFlowReturn ret = GST_FLOW_OK;
GstBuffer *buffer;
if (!g_atomic_int_get (&self->processing))
goto done;
GST_DEBUG_OBJECT (self, "Finishing decoding");
GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
if (gst_v4l2_decoder_cmd (self->v4l2output, V4L2_DEC_CMD_STOP, 0)) {
GstTask *task = decoder->srcpad->task;
/* If the decoder stop command succeeded, just wait until processing is
* finished */
GST_OBJECT_LOCK (task);
while (GST_TASK_STATE (task) == GST_TASK_STARTED)
GST_TASK_WAIT (task);
GST_OBJECT_UNLOCK (task);
ret = GST_FLOW_FLUSHING;
} else {
/* otherwise keep queuing empty buffers until the processing thread has
* stopped, _pool_process() will return FLUSHING when that happened */
while (ret == GST_FLOW_OK) {
buffer = gst_buffer_new ();
ret =
gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->
v4l2output->pool), &buffer);
gst_buffer_unref (buffer);
}
}
/* and ensure the processing thread has stopped in case another error
* occured. */
gst_v4l2_object_unlock (self->v4l2capture);
gst_pad_stop_task (decoder->srcpad);
GST_VIDEO_DECODER_STREAM_LOCK (decoder);
if (ret == GST_FLOW_FLUSHING)
ret = self->output_flow;
GST_DEBUG_OBJECT (decoder, "Done draining buffers");
done:
return ret;
}
static void
gst_task_func (GstTask * task, GstTaskClass * tclass)
{
GStaticRecMutex *lock;
GThread *tself;
tself = g_thread_self ();
GST_DEBUG ("Entering task %p, thread %p", task, tself);
/* we have to grab the lock to get the mutex. We also
* mark our state running so that nobody can mess with
* the mutex. */
GST_OBJECT_LOCK (task);
if (task->state == GST_TASK_STOPPED)
goto exit;
lock = GST_TASK_GET_LOCK (task);
if (G_UNLIKELY (lock == NULL))
goto no_lock;
task->abidata.ABI.thread = tself;
GST_OBJECT_UNLOCK (task);
/* locking order is TASK_LOCK, LOCK */
g_static_rec_mutex_lock (lock);
GST_OBJECT_LOCK (task);
while (G_LIKELY (task->state != GST_TASK_STOPPED)) {
while (G_UNLIKELY (task->state == GST_TASK_PAUSED)) {
gint t;
t = g_static_rec_mutex_unlock_full (lock);
if (t <= 0) {
g_warning ("wrong STREAM_LOCK count %d", t);
}
GST_TASK_SIGNAL (task);
GST_TASK_WAIT (task);
GST_OBJECT_UNLOCK (task);
/* locking order.. */
if (t > 0)
g_static_rec_mutex_lock_full (lock, t);
GST_OBJECT_LOCK (task);
if (G_UNLIKELY (task->state == GST_TASK_STOPPED))
goto done;
}
GST_OBJECT_UNLOCK (task);
task->func (task->data);
GST_OBJECT_LOCK (task);
}
done:
GST_OBJECT_UNLOCK (task);
g_static_rec_mutex_unlock (lock);
GST_OBJECT_LOCK (task);
task->abidata.ABI.thread = NULL;
exit:
/* now we allow messing with the lock again by setting the running flag to
* FALSE. Together with the SIGNAL this is the sign for the _join() to
* complete.
* Note that we still have not dropped the final ref on the task. We could
* check here if there is a pending join() going on and drop the last ref
* before releasing the lock as we can be sure that a ref is held by the
* caller of the join(). */
task->running = FALSE;
GST_TASK_SIGNAL (task);
GST_OBJECT_UNLOCK (task);
GST_DEBUG ("Exit task %p, thread %p", task, g_thread_self ());
gst_object_unref (task);
return;
no_lock:
{
g_warning ("starting task without a lock");
goto exit;
}
}
static void
gst_task_func (GstTask * task)
{
GStaticRecMutex *lock;
GThread *tself;
GstTaskPrivate *priv;
priv = task->priv;
tself = g_thread_self ();
GST_DEBUG ("Entering task %p, thread %p", task, tself);
/* we have to grab the lock to get the mutex. We also
* mark our state running so that nobody can mess with
* the mutex. */
GST_OBJECT_LOCK (task);
if (task->state == GST_TASK_STOPPED)
goto exit;
lock = GST_TASK_GET_LOCK (task);
if (G_UNLIKELY (lock == NULL))
goto no_lock;
task->abidata.ABI.thread = tself;
/* only update the priority when it was changed */
if (priv->prio_set)
g_thread_set_priority (tself, priv->priority);
GST_OBJECT_UNLOCK (task);
/* fire the enter_thread callback when we need to */
if (priv->thr_callbacks.enter_thread)
priv->thr_callbacks.enter_thread (task, tself, priv->thr_user_data);
/* locking order is TASK_LOCK, LOCK */
g_static_rec_mutex_lock (lock);
GST_OBJECT_LOCK (task);
/* configure the thread name now */
gst_task_configure_name (task);
while (G_LIKELY (task->state != GST_TASK_STOPPED)) {
while (G_UNLIKELY (task->state == GST_TASK_PAUSED)) {
gint t;
t = g_static_rec_mutex_unlock_full (lock);
if (t <= 0) {
g_warning ("wrong STREAM_LOCK count %d", t);
}
GST_TASK_SIGNAL (task);
GST_TASK_WAIT (task);
GST_OBJECT_UNLOCK (task);
/* locking order.. */
if (t > 0)
g_static_rec_mutex_lock_full (lock, t);
GST_OBJECT_LOCK (task);
if (G_UNLIKELY (task->state == GST_TASK_STOPPED))
goto done;
}
GST_OBJECT_UNLOCK (task);
task->func (task->data);
GST_OBJECT_LOCK (task);
}
done:
GST_OBJECT_UNLOCK (task);
g_static_rec_mutex_unlock (lock);
GST_OBJECT_LOCK (task);
task->abidata.ABI.thread = NULL;
exit:
if (priv->thr_callbacks.leave_thread) {
/* fire the leave_thread callback when we need to. We need to do this before
* we signal the task and with the task lock released. */
GST_OBJECT_UNLOCK (task);
priv->thr_callbacks.leave_thread (task, tself, priv->thr_user_data);
GST_OBJECT_LOCK (task);
} else {
/* restore normal priority when releasing back into the pool, we will not
* touch the priority when a custom callback has been installed. */
g_thread_set_priority (tself, G_THREAD_PRIORITY_NORMAL);
}
/* now we allow messing with the lock again by setting the running flag to
* FALSE. Together with the SIGNAL this is the sign for the _join() to
* complete.
* Note that we still have not dropped the final ref on the task. We could
* check here if there is a pending join() going on and drop the last ref
* before releasing the lock as we can be sure that a ref is held by the
* caller of the join(). */
task->running = FALSE;
GST_TASK_SIGNAL (task);
GST_OBJECT_UNLOCK (task);
GST_DEBUG ("Exit task %p, thread %p", task, g_thread_self ());
gst_object_unref (task);
return;
no_lock:
{
g_warning ("starting task without a lock");
goto exit;
}
}
static void
gst_hls_demux_loop (GstHLSDemux * demux)
{
GstBuffer *buf;
GstFlowReturn ret;
/* Loop for the source pad task. The task is started when we have
* received the main playlist from the source element. It tries first to
* cache the first fragments and then it waits until it has more data in the
* queue. This task is woken up when we push a new fragment to the queue or
* when we reached the end of the playlist */
if (G_UNLIKELY (demux->need_cache)) {
if (!gst_hls_demux_cache_fragments (demux))
goto cache_error;
/* we can start now the updates thread */
gst_hls_demux_start_update (demux);
GST_INFO_OBJECT (demux, "First fragments cached successfully");
}
if (g_queue_is_empty (demux->queue)) {
if (demux->end_of_playlist)
goto end_of_playlist;
GST_TASK_WAIT (demux->task);
/* If the queue is still empty check again if it's the end of the
* playlist in case we reached it after beeing woken up */
if (g_queue_is_empty (demux->queue) && demux->end_of_playlist)
goto end_of_playlist;
}
buf = g_queue_pop_head (demux->queue);
ret = gst_pad_push (demux->srcpad, buf);
if (ret != GST_FLOW_OK)
goto error;
return;
end_of_playlist:
{
GST_DEBUG_OBJECT (demux, "Reached end of playlist, sending EOS");
gst_pad_push_event (demux->srcpad, gst_event_new_eos ());
gst_hls_demux_stop (demux);
return;
}
cache_error:
{
GST_ELEMENT_ERROR (demux, RESOURCE, NOT_FOUND,
("Could not cache the first fragments"), NULL);
gst_hls_demux_stop (demux);
return;
}
error:
{
/* FIXME: handle error */
gst_hls_demux_stop (demux);
return;
}
}
