Flushing a pipeline with appsrc

[Alexey Chernov]

Hello,

IIRC I asked about a proper way of flushing pipeline here previously, but 
unfortunately it still remains a great mystery for me. However, as we 
discussed in the report on this 
(https://bugzilla.gnome.org/show_bug.cgi?id=689113), it became easier in 1.0, 
so I hope things would get clearer for me now.

I have the following pipeline:

Audio: appsrc -> decodebin -> autoaudiosink
Video: appsrc -> decodebin -> videoconvert -> videoscale -> autovideosink

with some possible variations. My use case is that I feed the pipeline's 
appsrcs with data received from network. Sometimes I also receive a signal 
along with the data unit to present it as soon as possible, so ideally I want 
to send flush to the pipeline to have all the internal queues cleared. If I got 
it right, I should do the following:

  gboolean ret = FALSE;
  GstEvent *flush_start, *flush_stop;

  GST_INFO_OBJECT(pipeline, "flushing pipeline...");
  flush_start = gst_event_new_flush_start();
  flush_stop = gst_event_new_flush_stop(FALSE);

  ret = gst_element_send_event(GST_ELEMENT(pipeline), flush_start);
  if (!ret)
    GST_INFO_OBJECT(pipeline, "failed to send flush-start event");
  ret = gst_element_send_event(GST_ELEMENT(pipeline), flush_stop);
  if (!ret)
    GST_INFO_OBJECT(pipeline, "failed to send flush-stop event");

But trying to do this exactly renders my pipeline stalling. I use FLUSH_STOP 
event without reset_time flag which should apparently help as I keep 
timestamping input buffers monotonically, but neither FALSE nor TRUE value does 
help.

Obviously I don't make it the proper way or use it in a wrong manner. How can 
it be done properly?

Thanks for any help.

Best regards,
Alexey Chernov