rtspsrc: De-dup seek event seqnums to avoid multiple seeksHEADmaster

Seek events are sent upstream on each sink, so if we receive multiple
seeks with the same seqnum, we must only perform one seek, not N seeks
where N = the number of sinks in the pipeline connected to rtspsrc.

This is the same thing done by demuxers like qtdemux or matrsokademux.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/938>

1 files changed, 9 insertions, 1 deletions

diff --git a/gst/rtsp/gstrtspsrc.c b/gst/rtsp/gstrtspsrc.c
index e59e05e40..51a70b73b 100644
--- a/gst/rtsp/gstrtspsrc.c
+++ b/gst/rtsp/gstrtspsrc.c
@@ -2978,7 +2978,15 @@ gst_rtspsrc_handle_src_event (GstPad * pad, GstObject * parent,
 
   switch (GST_EVENT_TYPE (event)) {
     case GST_EVENT_SEEK:
-      res = gst_rtspsrc_perform_seek (src, event);
+    {
+      guint32 seqnum = gst_event_get_seqnum (event);
+      if (seqnum == src->seek_seqnum) {
+        GST_LOG_OBJECT (pad, "Drop duplicated SEEK event seqnum %"
+            G_GUINT32_FORMAT, seqnum);
+      } else {
+        res = gst_rtspsrc_perform_seek (src, event);
+      }
+    }
       forward = FALSE;
       break;
     case GST_EVENT_QOS: