qtdemux: Clear protection events when we get new ones

If we keep the old events they can be end up being passed to the app, that could
discard the protection information because it has been seen before.

Drive by improvement: use g_queue_clear_full instead of foreach+clear for
protection events.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3547>

diff --git a/subprojects/gst-plugins-good/gst/isomp4/qtdemux.c b/subprojects/gst-plugins-good/gst/isomp4/qtdemux.c
index 2d1887a..845f1a0 100644 (file)
--- a/subprojects/gst-plugins-good/gst/isomp4/qtdemux.c
+++ b/subprojects/gst-plugins-good/gst/isomp4/qtdemux.c
@@ -392,6 +392,8 @@ static void gst_qtdemux_append_protection_system_id (GstQTDemux * qtdemux,
     const gchar * id);
 static void qtdemux_gst_structure_free (GstStructure * gststructure);
 static void gst_qtdemux_reset (GstQTDemux * qtdemux, gboolean hard);
+static void qtdemux_clear_protection_events_on_all_streams (GstQTDemux *
+    qtdemux);
 
 static void
 gst_qtdemux_class_init (GstQTDemuxClass * klass)
@@ -482,9 +484,8 @@ gst_qtdemux_dispose (GObject * object)
   }
   gst_tag_list_unref (qtdemux->tag_list);
   gst_flow_combiner_free (qtdemux->flowcombiner);
-  g_queue_foreach (&qtdemux->protection_event_queue, (GFunc) gst_event_unref,
-      NULL);
-  g_queue_clear (&qtdemux->protection_event_queue);
+  g_queue_clear_full (&qtdemux->protection_event_queue,
+      (GDestroyNotify) gst_event_unref);
 
   g_free (qtdemux->cenc_aux_info_sizes);
   qtdemux->cenc_aux_info_sizes = NULL;
@@ -2039,9 +2040,8 @@ gst_qtdemux_reset (GstQTDemux * qtdemux, gboolean hard)
     qtdemux->have_group_id = FALSE;
     qtdemux->group_id = G_MAXUINT;
 
-    g_queue_foreach (&qtdemux->protection_event_queue, (GFunc) gst_event_unref,
-        NULL);
-    g_queue_clear (&qtdemux->protection_event_queue);
+    g_queue_clear_full (&qtdemux->protection_event_queue,
+        (GDestroyNotify) gst_event_unref);
 
     qtdemux->received_seek = FALSE;
     qtdemux->first_moof_already_parsed = FALSE;
@@ -2099,6 +2099,15 @@ gst_qtdemux_reset (GstQTDemux * qtdemux, gboolean hard)
   }
 }
 
+static void
+qtdemux_clear_protection_events_on_all_streams (GstQTDemux * qtdemux)
+{
+  for (unsigned i = 0; i < QTDEMUX_N_STREAMS (qtdemux); i++) {
+    QtDemuxStream *stream = QTDEMUX_NTH_STREAM (qtdemux, i);
+    g_queue_clear_full (&stream->protection_scheme_event_queue,
+        (GDestroyNotify) gst_event_unref);
+  }
+}
 
 /* Maps the @segment to the qt edts internal segments and pushes
  * the corresponding segment event.
@@ -2574,9 +2583,8 @@ gst_qtdemux_stream_clear (QtDemuxStream * stream)
   }
   stream->protection_scheme_type = 0;
   stream->protection_scheme_version = 0;
-  g_queue_foreach (&stream->protection_scheme_event_queue,
-      (GFunc) gst_event_unref, NULL);
-  g_queue_clear (&stream->protection_scheme_event_queue);
+  g_queue_clear_full (&stream->protection_scheme_event_queue,
+      (GDestroyNotify) gst_event_unref);
   gst_qtdemux_stream_flush_segments_data (stream);
   gst_qtdemux_stream_flush_samples_data (stream);
 }
@@ -4292,6 +4300,10 @@ qtdemux_parse_moof (GstQTDemux * qtdemux, const guint8 * buffer, guint length,
 
   /* parse any protection system info */
   pssh_node = qtdemux_tree_get_child_by_type (moof_node, FOURCC_pssh);
+  if (pssh_node) {
+    /* Unref old protection events if we are going to receive new ones. */
+    qtdemux_clear_protection_events_on_all_streams (qtdemux);
+  }
   while (pssh_node) {
     GST_LOG_OBJECT (qtdemux, "Parsing pssh box.");
     qtdemux_parse_pssh (qtdemux, pssh_node);
@@ -14113,6 +14125,10 @@ qtdemux_parse_tree (GstQTDemux * qtdemux)
 
   /* parse any protection system info */
   pssh = qtdemux_tree_get_child_by_type (qtdemux->moov_node, FOURCC_pssh);
+  if (pssh) {
+    /* Unref old protection events if we are going to receive new ones. */
+    qtdemux_clear_protection_events_on_all_streams (qtdemux);
+  }
   while (pssh) {
     GST_LOG_OBJECT (qtdemux, "Parsing pssh box.");
     qtdemux_parse_pssh (qtdemux, pssh);