decodebin2: Forward event/queries for unlinked groups

When upstream events/queries reach sinkpads of unlinked groups (i.e.
no longer linked to the upstream demuxer), this patch attempts to find
the linked group and forward it upstream of that group.

This is done by adding upstream event/query probes on new group sinkpads
and then:
* Checking if the pad is linked or not (has a peer or not)
* If there is a peer, just let the event/query follow through normally
* If there is no peer, we find a pad to which to proxy it and return
  GST_PROBE_HANDLED if it succeeded (allowing the event/query to be properly
  returned to the initial called)

Note that this is definitely not thread-safe for the time being

https://bugzilla.gnome.org/show_bug.cgi?id=606382
This commit is contained in:
Edward Hervey 2015-04-29 15:56:39 +02:00 committed by Edward Hervey
parent d19f347223
commit 2d3743e37d

View file

@ -2853,6 +2853,81 @@ pad_added_cb (GstElement * element, GstPad * pad, GstDecodeChain * chain)
EXPOSE_UNLOCK (dbin);
}
static GstPadProbeReturn
sink_pad_event_probe (GstPad * pad, GstPadProbeInfo * info, gpointer user_data)
{
GstDecodeGroup *group = (GstDecodeGroup *) user_data;
GstEvent *event = GST_PAD_PROBE_INFO_EVENT (info);
GstPad *peer = gst_pad_get_peer (pad);
GstPadProbeReturn proberet = GST_PAD_PROBE_OK;
GST_DEBUG_OBJECT (pad, "Got upstream event %s", GST_EVENT_TYPE_NAME (event));
if (peer == NULL) {
GST_DEBUG_OBJECT (pad, "We are unlinked !");
if (group->parent && group->parent->next_groups) {
GstDecodeGroup *last_group =
g_list_last (group->parent->next_groups)->data;
GST_DEBUG_OBJECT (pad, "We could send the event to another group (%p)",
last_group);
/* Grab another sinkpad for that last group through which we will forward this event */
if (last_group->reqpads) {
GstPad *sinkpad = (GstPad *) last_group->reqpads->data;
GstPad *otherpeer = gst_pad_get_peer (sinkpad);
if (otherpeer) {
GST_DEBUG_OBJECT (otherpeer, "Attempting to forward event");
if (gst_pad_send_event (otherpeer, gst_event_ref (event))) {
proberet = GST_PAD_PROBE_HANDLED;
}
gst_object_unref (otherpeer);
}
} else
GST_DEBUG_OBJECT (pad, "No request pads, can't forward event");
}
} else
gst_object_unref (peer);
return proberet;
}
static GstPadProbeReturn
sink_pad_query_probe (GstPad * pad, GstPadProbeInfo * info, gpointer user_data)
{
GstDecodeGroup *group = (GstDecodeGroup *) user_data;
GstPad *peer = gst_pad_get_peer (pad);
GstQuery *query = GST_PAD_PROBE_INFO_QUERY (info);
GstPadProbeReturn proberet = GST_PAD_PROBE_OK;
GST_DEBUG_OBJECT (pad, "Got upstream query %s", GST_QUERY_TYPE_NAME (query));
if (peer == NULL) {
GST_DEBUG_OBJECT (pad, "We are unlinked !");
if (group->parent && group->parent->next_groups) {
GstDecodeGroup *last_group =
g_list_last (group->parent->next_groups)->data;
GST_DEBUG_OBJECT (pad, "We could send the query to another group");
/* Grab another sinkpad for that last group through which we will forward this event */
if (last_group->reqpads) {
GstPad *sinkpad = (GstPad *) last_group->reqpads->data;
GstPad *otherpeer = gst_pad_get_peer (sinkpad);
if (otherpeer) {
GST_DEBUG_OBJECT (otherpeer, "Attempting to forward query");
if (gst_pad_query (otherpeer, query)) {
proberet = GST_PAD_PROBE_HANDLED;
} else
GST_DEBUG ("FAILURE");
gst_object_unref (otherpeer);
} else
GST_DEBUG_OBJECT (sinkpad, "request pad not connected ??");
} else
GST_DEBUG_OBJECT (pad, "No request pads ???");
}
} else
gst_object_unref (peer);
return proberet;
}
static void
pad_removed_cb (GstElement * element, GstPad * pad, GstDecodeChain * chain)
{
@ -3675,6 +3750,11 @@ gst_decode_group_control_demuxer_pad (GstDecodeGroup * group, GstPad * pad)
sinkpad);
goto error;
}
gst_pad_add_probe (sinkpad, GST_PAD_PROBE_TYPE_EVENT_UPSTREAM,
sink_pad_event_probe, group, NULL);
gst_pad_add_probe (sinkpad, GST_PAD_PROBE_TYPE_QUERY_UPSTREAM,
sink_pad_query_probe, group, NULL);
CHAIN_MUTEX_LOCK (group->parent);
group->reqpads = g_list_prepend (group->reqpads, gst_object_ref (sinkpad));
CHAIN_MUTEX_UNLOCK (group->parent);