From 0fbbdc5734bb4b6f13532d2b809fd1d08cabb97c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Olivier=20Cr=C3=AAte?= <olivier.crete@collabora.com>
Date: Thu, 9 Jul 2020 13:42:35 -0400
Subject: [PATCH] rtptransceiver: Store the SSRC of the current stream

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1707>
---
 ext/webrtc/gstwebrtcbin.c      | 8 ++++++++
 ext/webrtc/webrtctransceiver.h | 1 +
 2 files changed, 9 insertions(+)

diff --git a/ext/webrtc/gstwebrtcbin.c b/ext/webrtc/gstwebrtcbin.c
index dbe919e53c..79b79d6eae 100644
--- a/ext/webrtc/gstwebrtcbin.c
+++ b/ext/webrtc/gstwebrtcbin.c
@@ -265,6 +265,14 @@ gst_webrtcbin_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
     GST_DEBUG_OBJECT (parent,
         "On %" GST_PTR_FORMAT " checking negotiation? %u, caps %"
         GST_PTR_FORMAT, pad, check_negotiation, caps);
+
+    if (check_negotiation) {
+      WebRTCTransceiver *trans = WEBRTC_TRANSCEIVER (wpad->trans);
+      const GstStructure *s;
+
+      s = gst_caps_get_structure (caps, 0);
+      gst_structure_get_uint (s, "ssrc", &trans->current_ssrc);
+    }
   } else if (GST_EVENT_TYPE (event) == GST_EVENT_EOS) {
     check_negotiation = TRUE;
   }
diff --git a/ext/webrtc/webrtctransceiver.h b/ext/webrtc/webrtctransceiver.h
index c037304151..f834fd329a 100644
--- a/ext/webrtc/webrtctransceiver.h
+++ b/ext/webrtc/webrtctransceiver.h
@@ -39,6 +39,7 @@ struct _WebRTCTransceiver
 
   TransportStream          *stream;
   GstStructure             *local_rtx_ssrc_map;
+  guint                     current_ssrc;
 
   /* Properties */
   GstWebRTCFECType         fec_type;