mpegtbase: vmethod to notify when we're done processing input

This can be used to notify subclasses no more data is expected this
round.
tsparse will use it to push whole buffers (without copy) on the main
source pad.
It could also be used later to decide whether to push pending data
in order to reduce latency.

gst/mpegtsdemux/mpegtsbase.c

@@ -1409,14 +1409,20 @@ mpegts_base_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
   MpegTSPacketizerPacketReturn pret;
   MpegTSPacketizer2 *packetizer;
   MpegTSPacketizerPacket packet;
+  MpegTSBaseClass *klass;
 
   base = GST_MPEGTS_BASE (parent);
+  klass = GST_MPEGTS_BASE_GET_CLASS (base);
+
   packetizer = base->packetizer;
 
   if (G_UNLIKELY (base->queried_latency == FALSE)) {
     query_upstream_latency (base);
   }
 
+  if (klass->input_done)
+    gst_buffer_ref (buf);
+
   mpegts_packetizer_push (base->packetizer, buf);
 
   while (res == GST_FLOW_OK) {
@@ -1465,6 +1471,13 @@ mpegts_base_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
     mpegts_packetizer_clear_packet (base->packetizer, &packet);
   }
 
+  if (klass->input_done) {
+    if (res == GST_FLOW_OK)
+      res = klass->input_done (base, buf);
+    else
+      gst_buffer_unref (buf);
+  }
+
   return res;
 }
 

gst/mpegtsdemux/mpegtsbase.h

@@ -168,6 +168,9 @@ struct _MpegTSBaseClass {
   /* flush all streams */
   void (*flush) (MpegTSBase * base);
 
+  /* Notifies subclasses input buffer has been handled */
+  GstFlowReturn (*input_done) (MpegTSBase *base, GstBuffer *buffer);
+
   /* signals */
   void (*pat_info) (GstStructure *pat);
   void (*pmt_info) (GstStructure *pmt);