decodebin3: Don't output bogus GST_MESSAGE_STREAMS_SELECTED

When `is_selection_done` is called, it checks that all the requested streams are
present in the active stream list ...

... except there could very well be a (about to be removed) stream from the
previous selection present.

Therefore filter the list of streams we add to the message by the streams which
are actually requested.

Fixes issues when switching between different stream types (ex: video-only to
audio-only).

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3457>

diff --git a/subprojects/gst-plugins-base/gst/playback/gstdecodebin3.c b/subprojects/gst-plugins-base/gst/playback/gstdecodebin3.c
index c5543b8..f9dab82 100644 (file)
--- a/subprojects/gst-plugins-base/gst/playback/gstdecodebin3.c
+++ b/subprojects/gst-plugins-base/gst/playback/gstdecodebin3.c
@@ -2106,10 +2106,14 @@ is_selection_done (GstDecodebin3 * dbin)
   for (tmp = dbin->output_streams; tmp; tmp = tmp->next) {
     DecodebinOutputStream *output = (DecodebinOutputStream *) tmp->data;
     if (output->slot) {
-      GST_DEBUG_OBJECT (dbin, "Adding stream %s",
-          gst_stream_get_stream_id (output->slot->active_stream));
-
-      gst_message_streams_selected_add (msg, output->slot->active_stream);
+      const gchar *output_streamid =
+          gst_stream_get_stream_id (output->slot->active_stream);
+      GST_DEBUG_OBJECT (dbin, "Adding stream %s", output_streamid);
+      if (stream_in_list (dbin->requested_selection, output_streamid))
+        gst_message_streams_selected_add (msg, output->slot->active_stream);
+      else
+        GST_WARNING_OBJECT (dbin,
+            "Output slot still active for old selection ?");
     } else
       GST_WARNING_OBJECT (dbin, "No valid slot for output %p", output);
   }