From 50638b81063e8215bbcc6eeedd5a0f16896076f1 Mon Sep 17 00:00:00 2001
From: Wim Taymans <wim.taymans@collabora.co.uk>
Date: Sun, 4 Aug 2013 23:05:36 +0200
Subject: [PATCH] session: handle Retransmission event and schedule NACK

Handle the retransmission event from downstream and use it to schedule a NACK
request.
---
 gst/rtpmanager/gstrtpsession.c | 18 ++++++++++++++++++
 gst/rtpmanager/rtpsession.c    | 17 ++++++++++++++++-
 gst/rtpmanager/rtpsession.h    |  5 +++++
 3 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/gst/rtpmanager/gstrtpsession.c b/gst/rtpmanager/gstrtpsession.c
index 143f4a3..9a9c4e1 100644
--- a/gst/rtpmanager/gstrtpsession.c
+++ b/gst/rtpmanager/gstrtpsession.c
@@ -1499,6 +1499,24 @@ gst_rtp_session_event_recv_rtp_src (GstPad * pad, GstObject * parent,
         if (gst_rtp_session_request_remote_key_unit (rtpsession, ssrc, pt,
                 all_headers, count))
           forward = FALSE;
+      } else if (gst_structure_has_name (s, "GstRTPRetransmissionRequest")) {
+        GstClockTime running_time;
+        guint seqnum, delay, deadline;
+
+        if (!gst_structure_get_clock_time (s, "running-time", &running_time))
+          running_time = -1;
+        if (!gst_structure_get_uint (s, "ssrc", &ssrc))
+          ssrc = -1;
+        if (!gst_structure_get_uint (s, "seqnum", &seqnum))
+          seqnum = -1;
+        if (!gst_structure_get_uint (s, "delay", &deadline))
+          delay = -1;
+        if (!gst_structure_get_uint (s, "deadline", &deadline))
+          deadline = -1;
+
+        if (rtp_session_request_nack (rtpsession->priv->session, ssrc, seqnum,
+                (deadline - delay) * GST_MSECOND))
+          forward = FALSE;
       }
       break;
     default:
diff --git a/gst/rtpmanager/rtpsession.c b/gst/rtpmanager/rtpsession.c
index c91d948..64616b3 100644
--- a/gst/rtpmanager/rtpsession.c
+++ b/gst/rtpmanager/rtpsession.c
@@ -113,7 +113,6 @@ static void rtp_session_get_property (GObject * object, guint prop_id,
 
 static void rtp_session_send_rtcp (RTPSession * sess, GstClockTime max_delay);
 
-
 static guint rtp_session_signals[LAST_SIGNAL] = { 0 };
 
 G_DEFINE_TYPE (RTPSession, rtp_session, G_TYPE_OBJECT);
@@ -3515,3 +3514,19 @@ rtp_session_request_key_unit (RTPSession * sess, guint32 ssrc,
 
   return TRUE;
 }
+
+gboolean
+rtp_session_request_nack (RTPSession * sess, guint32 ssrc, guint16 seqnum,
+    GstClockTime max_delay)
+{
+  RTPSource *source = find_source (sess, ssrc);
+
+  if (source == NULL)
+    return FALSE;
+
+  GST_DEBUG ("request NACK for %08x, #%u", ssrc, seqnum);
+
+  rtp_session_send_rtcp (sess, max_delay);
+
+  return TRUE;
+}
diff --git a/gst/rtpmanager/rtpsession.h b/gst/rtpmanager/rtpsession.h
index 1fa04ac..7867bac 100644
--- a/gst/rtpmanager/rtpsession.h
+++ b/gst/rtpmanager/rtpsession.h
@@ -345,5 +345,10 @@ gboolean        rtp_session_request_key_unit       (RTPSession * sess,
                                                     guint32 ssrc,
                                                     gboolean fir,
                                                     gint count);
+gboolean        rtp_session_request_nack           (RTPSession * sess,
+                                                    guint32 ssrc,
+                                                    guint16 seqnum,
+                                                    GstClockTime max_delay);
+
 
 #endif /* __RTP_SESSION_H__ */
-- 
2.7.4