adaptivedemux: Stop prepared streams as well as running streams

There can be twice as many stream tasks running as there are output
pads for playback of variant HLS playlists. Half of them are the
current pads, and the other half are the pads that are about to be
switched to due to a bitrate change.
The old code only stopped the current streams which could result
in a deadlock on stopping the pipeline. The changes force stopping
and joining of any prepared streams too.

https://bugzilla.gnome.org/show_bug.cgi?id=785987

1 files changed, 40 insertions, 25 deletions

diff --git a/gst-libs/gst/adaptivedemux/gstadaptivedemux.c b/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
index c41b75a08b..7b7d1fc527 100644
--- a/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
+++ b/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
@@ -2059,20 +2059,27 @@ gst_adaptive_demux_start_manifest_update_task (GstAdaptiveDemux * demux)
 static void
 gst_adaptive_demux_stop_tasks (GstAdaptiveDemux * demux, gboolean stop_updates)
 {
+  int i;
   GList *iter;
+  GList *list_to_process;
 
   GST_LOG_OBJECT (demux, "Stopping tasks");
 
   if (stop_updates)
     gst_adaptive_demux_stop_manifest_update_task (demux);
-  for (iter = demux->streams; iter; iter = g_list_next (iter)) {
-    GstAdaptiveDemuxStream *stream = iter->data;
 
-    g_mutex_lock (&stream->fragment_download_lock);
-    stream->cancelled = TRUE;
-    gst_task_stop (stream->download_task);
-    g_cond_signal (&stream->fragment_download_cond);
-    g_mutex_unlock (&stream->fragment_download_lock);
+  list_to_process = demux->streams;
+  for (i = 0; i < 2; ++i) {
+    for (iter = list_to_process; iter; iter = g_list_next (iter)) {
+      GstAdaptiveDemuxStream *stream = iter->data;
+
+      g_mutex_lock (&stream->fragment_download_lock);
+      stream->cancelled = TRUE;
+      gst_task_stop (stream->download_task);
+      g_cond_signal (&stream->fragment_download_cond);
+      g_mutex_unlock (&stream->fragment_download_lock);
+    }
+    list_to_process = demux->prepared_streams;
   }
 
   GST_MANIFEST_UNLOCK (demux);
@@ -2090,23 +2097,27 @@ gst_adaptive_demux_stop_tasks (GstAdaptiveDemux * demux, gboolean stop_updates)
    * object. Even if we temporarily release manifest_lock, the demux->streams
    * cannot change and iter cannot be invalidated.
    */
-  for (iter = demux->streams; iter; iter = g_list_next (iter)) {
-    GstAdaptiveDemuxStream *stream = iter->data;
-    GstElement *src = stream->src;
+  list_to_process = demux->streams;
+  for (i = 0; i < 2; ++i) {
+    for (iter = list_to_process; iter; iter = g_list_next (iter)) {
+      GstAdaptiveDemuxStream *stream = iter->data;
+      GstElement *src = stream->src;
 
-    GST_MANIFEST_UNLOCK (demux);
+      GST_MANIFEST_UNLOCK (demux);
 
-    if (src) {
-      gst_element_set_locked_state (src, TRUE);
-      gst_element_set_state (src, GST_STATE_READY);
-    }
+      if (src) {
+        gst_element_set_locked_state (src, TRUE);
+        gst_element_set_state (src, GST_STATE_READY);
+      }
 
-    /* stream->download_task value never changes, so it is safe to read it
-     * outside critical section
-     */
-    gst_task_join (stream->download_task);
+      /* stream->download_task value never changes, so it is safe to read it
+       * outside critical section
+       */
+      gst_task_join (stream->download_task);
 
-    GST_MANIFEST_LOCK (demux);
+      GST_MANIFEST_LOCK (demux);
+    }
+    list_to_process = demux->prepared_streams;
   }
 
   GST_MANIFEST_UNLOCK (demux);
@@ -2115,12 +2126,16 @@ gst_adaptive_demux_stop_tasks (GstAdaptiveDemux * demux, gboolean stop_updates)
 
   GST_MANIFEST_LOCK (demux);
 
-  for (iter = demux->streams; iter; iter = g_list_next (iter)) {
-    GstAdaptiveDemuxStream *stream = iter->data;
+  list_to_process = demux->streams;
+  for (i = 0; i < 2; ++i) {
+    for (iter = list_to_process; iter; iter = g_list_next (iter)) {
+      GstAdaptiveDemuxStream *stream = iter->data;
 
-    stream->download_error_count = 0;
-    stream->need_header = TRUE;
-    stream->qos_earliest_time = GST_CLOCK_TIME_NONE;
+      stream->download_error_count = 0;
+      stream->need_header = TRUE;
+      stream->qos_earliest_time = GST_CLOCK_TIME_NONE;
+    }
+    list_to_process = demux->prepared_streams;
   }
 }