matroska-mux: Wait for caps on sparse streams

Don't set sparse streams to non-waiting at the collectpads
level until after capa arrive, as we need caps on all
pads before the file headers get written, or else the
subtitle track will be silently absent in the final file.

Fixes https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/issues/724

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/656>

diff --git a/gst/matroska/matroska-mux.c b/gst/matroska/matroska-mux.c
index be76bf0..b99dd71 100644 (file)
--- a/gst/matroska/matroska-mux.c
+++ b/gst/matroska/matroska-mux.c
@@ -2254,6 +2254,8 @@ refuse_caps:
 static gboolean
 gst_matroska_mux_subtitle_pad_setcaps (GstPad * pad, GstCaps * caps)
 {
+  GstCollectData *data = (GstCollectData *) (pad);
+
   /* There is now (at least) one such alement (kateenc), and I'm going
      to handle it here and claim it works when it can be piped back
      through GStreamer and VLC */
@@ -2365,6 +2367,15 @@ gst_matroska_mux_subtitle_pad_setcaps (GstPad * pad, GstCaps * caps)
   GST_DEBUG_OBJECT (pad, "codec_id %s, codec data size %" G_GSIZE_FORMAT,
       GST_STR_NULL (context->codec_id), context->codec_priv_size);
 
+  /* This pad is sparse. Now that we have caps on it, we can tell collectpads
+   * not to actually wait for data when muxing */
+  GST_COLLECT_PADS_STREAM_LOCK (mux->collect);
+  GST_COLLECT_PADS_STATE_UNSET (data, GST_COLLECT_PADS_STATE_LOCKED);
+  gst_collect_pads_set_waiting (mux->collect, data, FALSE);
+  GST_COLLECT_PADS_STATE_SET (data, GST_COLLECT_PADS_STATE_LOCKED);
+  GST_COLLECT_PADS_STREAM_UNLOCK (mux->collect);
+
+
 exit:
 
   return ret;
@@ -2402,7 +2413,6 @@ gst_matroska_mux_request_new_pad (GstElement * element,
   GstMatroskaCapsFunc capsfunc = NULL;
   GstMatroskaTrackContext *context = NULL;
   gint pad_id;
-  gboolean locked = TRUE;
   const gchar *id = NULL;
 
   if (templ == gst_element_class_get_pad_template (klass, "audio_%u")) {
@@ -2449,7 +2459,6 @@ gst_matroska_mux_request_new_pad (GstElement * element,
     context->name = g_strdup ("Subtitle");
     /* setcaps may only provide proper one a lot later */
     id = "S_SUB_UNKNOWN";
-    locked = FALSE;
   } else {
     GST_WARNING_OBJECT (mux, "This is not our template!");
     return NULL;
@@ -2462,7 +2471,7 @@ gst_matroska_mux_request_new_pad (GstElement * element,
   collect_pad = (GstMatroskaPad *)
       gst_collect_pads_add_pad (mux->collect, GST_PAD (newpad),
       sizeof (GstMatroskaPad),
-      (GstCollectDataDestroyNotify) gst_matroska_pad_free, locked);
+      (GstCollectDataDestroyNotify) gst_matroska_pad_free, TRUE);
 
   collect_pad->mux = mux;
   collect_pad->track = context;