interleave: set src pad caps upon last sink pad CAPS event

Gather caps on all sink pads before setting the src pad caps. This is
specially needed when the audio channel mapping is set on the sink
pads and the element needs to preserve it on its src pad.

https://bugzilla.gnome.org/show_bug.cgi?id=690267

2 files changed, 37 insertions, 27 deletions

diff --git a/gst/interleave/interleave.c b/gst/interleave/interleave.c
index ebc189e66..4c46a094f 100644
--- a/gst/interleave/interleave.c
+++ b/gst/interleave/interleave.c
@@ -219,7 +219,7 @@ static gboolean gst_interleave_sink_event (GstCollectPads * pads,
     GstCollectData * data, GstEvent * event, gpointer user_data);
 
 static gboolean gst_interleave_sink_setcaps (GstInterleave * self,
-    GstPad * pad, const GstCaps * caps);
+    GstPad * pad, const GstCaps * caps, const GstAudioInfo * info);
 
 static GstCaps *gst_interleave_sink_getcaps (GstPad * pad, GstObject * parent,
     GstCaps * filter);
@@ -547,6 +547,9 @@ gst_interleave_release_pad (GstElement * element, GstPad * pad)
 
   g_atomic_int_add (&self->channels, -1);
 
+  if (gst_pad_has_current_caps (pad))
+    g_atomic_int_add (&self->configured_sinkpads_counter, -1);
+
   position = GST_INTERLEAVE_PAD_CAST (pad)->channel;
   g_value_array_remove (self->input_channel_positions, position);
 
@@ -734,11 +737,10 @@ gst_interleave_set_process_function (GstInterleave * self)
 
 static gboolean
 gst_interleave_sink_setcaps (GstInterleave * self, GstPad * pad,
-    const GstCaps * caps)
+    const GstCaps * caps, const GstAudioInfo * info)
 {
   g_return_val_if_fail (GST_IS_INTERLEAVE_PAD (pad), FALSE);
 
-  /* First caps that are set on a sink pad are used as output caps */
   /* TODO: handle caps changes */
   if (self->sinkcaps && !gst_caps_is_subset (caps, self->sinkcaps)) {
     goto cannot_change_caps;
@@ -746,25 +748,11 @@ gst_interleave_sink_setcaps (GstInterleave * self, GstPad * pad,
     GstCaps *srccaps;
     GstStructure *s;
     gboolean res;
-    GstAudioInfo info;
-    GValue *val;
-    guint channel;
-
-    if (!gst_audio_info_from_caps (&info, caps))
-      goto invalid_caps;
-
-    self->width = GST_AUDIO_INFO_WIDTH (&info);
-    self->rate = GST_AUDIO_INFO_RATE (&info);
 
+    self->width = GST_AUDIO_INFO_WIDTH (info);
+    self->rate = GST_AUDIO_INFO_RATE (info);
 
     gst_interleave_set_process_function (self);
-    channel = GST_INTERLEAVE_PAD_CAST (pad)->channel;
-
-    if (self->channel_positions_from_input
-        && GST_AUDIO_INFO_CHANNELS (&info) == 1) {
-      val = g_value_array_get_nth (self->input_channel_positions, channel);
-      g_value_set_enum (val, GST_AUDIO_INFO_POSITION (&info, 0));
-    }
 
     srccaps = gst_caps_copy (caps);
     s = gst_caps_get_structure (srccaps, 0);
@@ -808,11 +796,6 @@ src_did_not_accept:
     GST_WARNING_OBJECT (self, "src did not accept setcaps()");
     return FALSE;
   }
-invalid_caps:
-  {
-    GST_WARNING_OBJECT (self, "invalid sink caps");
-    return FALSE;
-  }
 }
 
 static gboolean
@@ -841,11 +824,37 @@ gst_interleave_sink_event (GstCollectPads * pads, GstCollectData * data,
     case GST_EVENT_CAPS:
     {
       GstCaps *caps;
+      GstAudioInfo info;
+      GValue *val;
+      guint channel;
 
       gst_event_parse_caps (event, &caps);
-      ret = gst_interleave_sink_setcaps (self, data->pad, caps);
-      gst_event_unref (event);
-      event = NULL;
+
+      if (!gst_audio_info_from_caps (&info, caps)) {
+        GST_WARNING_OBJECT (self, "invalid sink caps");
+        gst_event_unref (event);
+        event = NULL;
+        ret = FALSE;
+        break;
+      }
+
+      if (self->channel_positions_from_input
+          && GST_AUDIO_INFO_CHANNELS (&info) == 1) {
+        channel = GST_INTERLEAVE_PAD_CAST (data->pad)->channel;
+        val = g_value_array_get_nth (self->input_channel_positions, channel);
+        g_value_set_enum (val, GST_AUDIO_INFO_POSITION (&info, 0));
+      }
+
+      if (!gst_pad_has_current_caps (data->pad))
+        g_atomic_int_add (&self->configured_sinkpads_counter, 1);
+
+      /* Last caps that are set on a sink pad are used as output caps */
+      if (g_atomic_int_get (&self->configured_sinkpads_counter) ==
+          self->channels) {
+        ret = gst_interleave_sink_setcaps (self, data->pad, caps, &info);
+        gst_event_unref (event);
+        event = NULL;
+      }
       break;
     }
     case GST_EVENT_TAG:
diff --git a/gst/interleave/interleave.h b/gst/interleave/interleave.h
index 89d0e4c49..1e01d3ae4 100644
--- a/gst/interleave/interleave.h
+++ b/gst/interleave/interleave.h
@@ -61,6 +61,7 @@ struct _GstInterleave
   gboolean channel_positions_from_input;
 
   GstCaps *sinkcaps;
+  gint configured_sinkpads_counter;
 
   GstClockTime timestamp;
   guint64 offset;