diff options
Diffstat (limited to 'plugins/elements/gstmultiqueue.c')
| -rw-r--r-- | plugins/elements/gstmultiqueue.c | 35 |
1 files changed, 24 insertions, 11 deletions
diff --git a/plugins/elements/gstmultiqueue.c b/plugins/elements/gstmultiqueue.c index 9e9209c..7a9cd5f 100644 --- a/plugins/elements/gstmultiqueue.c +++ b/plugins/elements/gstmultiqueue.c @@ -1614,17 +1614,30 @@ gst_multi_queue_sink_query (GstPad * pad, GstObject * parent, GstQuery * query) if (sq->srcresult != GST_FLOW_OK) goto out_flushing; - /* Get an unique incrementing id. */ - curid = g_atomic_int_add ((gint *) & mq->counter, 1); - - item = gst_multi_queue_mo_item_new ((GstMiniObject *) query, curid); - - GST_DEBUG_OBJECT (mq, - "SingleQueue %d : Enqueuing query %p of type %s with id %d", - sq->id, query, GST_QUERY_TYPE_NAME (query), curid); - res = gst_data_queue_push (sq->queue, (GstDataQueueItem *) item); - g_cond_wait (&sq->query_handled, &mq->qlock); - res = sq->last_query; + /* serialized events go in the queue. We need to be certain that we + * don't cause deadlocks waiting for the query return value. We check if + * the queue is empty (nothing is blocking downstream and the query can + * be pushed for sure) or we are not buffering. If we are buffering, + * the pipeline waits to unblock downstream until our queue fills up + * completely, which can not happen if we block on the query.. + * Therefore we only potentially block when we are not buffering. */ + if (!mq->use_buffering || gst_data_queue_is_empty (sq->queue)) { + /* Get an unique incrementing id. */ + curid = g_atomic_int_add ((gint *) & mq->counter, 1); + + item = gst_multi_queue_mo_item_new ((GstMiniObject *) query, curid); + + GST_DEBUG_OBJECT (mq, + "SingleQueue %d : Enqueuing query %p of type %s with id %d", + sq->id, query, GST_QUERY_TYPE_NAME (query), curid); + res = gst_data_queue_push (sq->queue, (GstDataQueueItem *) item); + g_cond_wait (&sq->query_handled, &mq->qlock); + res = sq->last_query; + } else { + GST_DEBUG_OBJECT (mq, "refusing query, we are buffering and the " + "queue is not empty"); + res = FALSE; + } GST_MULTI_QUEUE_MUTEX_UNLOCK (mq); } else { /* default handling */ |