From 2c28c1372195c226bf5d5a65fb2c069146ab043e Mon Sep 17 00:00:00 2001
From: Martin Pulec <pulec@cesnet.cz>
Date: Sat, 26 Sep 2015 12:29:57 +0200
Subject: [PATCH] Control: allow SSRC change of the RTP stream

---
 src/audio/audio.cpp    | 17 +++++++++++++++++
 src/control_socket.cpp |  5 ++++-
 src/messaging.h        |  1 +
 src/video_rxtx/rtp.cpp | 20 ++++++++++++++++++++
 4 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/src/audio/audio.cpp b/src/audio/audio.cpp
index 7441242e6..42fa4ac85 100644
--- a/src/audio/audio.cpp
+++ b/src/audio/audio.cpp
@@ -780,6 +780,23 @@ static struct response *audio_sender_process_message(struct state_audio *s, stru
                         break;
                 case SENDER_MSG_QUERY_VIDEO_MODE:
                         return new_response(RESPONSE_BAD_REQUEST, NULL);
+                case SENDER_MSG_RESET_SSRC:
+                        {
+                                uint32_t old_ssrc = rtp_my_ssrc(s->audio_network_device);
+                                auto old_devices = s->audio_network_device;
+                                s->audio_network_device =
+                                        initialize_audio_network(&s->audio_network_parameters);
+                                if (!s->audio_network_device) {
+                                        s->audio_network_device = old_devices;
+                                        log_msg(LOG_LEVEL_ERROR, "[control] Audio: Unable to change SSRC!\n");
+                                        return new_response(RESPONSE_INT_SERV_ERR, NULL);
+                                } else {
+                                        rtp_done(old_devices);
+                                        log_msg(LOG_LEVEL_NOTICE, "[control] Audio: changed SSRC from 0x%08lx to "
+                                                        "0x%08lx.\n", old_ssrc, rtp_my_ssrc(s->audio_network_device));
+                                }
+                        }
+                        break;
                 case SENDER_MSG_CHANGE_FEC:
                         LOG(LOG_LEVEL_ERROR) << "Not implemented!\n";
                         return new_response(RESPONSE_NOT_IMPL, NULL);
diff --git a/src/control_socket.cpp b/src/control_socket.cpp
index 1a2f1247d..e4efad38b 100644
--- a/src/control_socket.cpp
+++ b/src/control_socket.cpp
@@ -327,7 +327,8 @@ static int process_msg(struct control_state *s, fd_t client_fd, char *message, s
                         }
                 }
         } else if(prefix_matches(message, "receiver ") || prefix_matches(message, "play") ||
-                        prefix_matches(message, "pause") || prefix_matches(message, "sender-port ")) {
+                        prefix_matches(message, "pause") || prefix_matches(message, "sender-port ") ||
+                        prefix_matches(message, "reset-ssrc")) {
                 struct msg_sender *msg =
                         (struct msg_sender *)
                         new_message(sizeof(struct msg_sender));
@@ -341,6 +342,8 @@ static int process_msg(struct control_state *s, fd_t client_fd, char *message, s
                         msg->type = SENDER_MSG_PLAY;
                 } else if(prefix_matches(message, "pause")) {
                         msg->type = SENDER_MSG_PAUSE;
+                } else if(prefix_matches(message, "reset-ssrc")) {
+                        msg->type = SENDER_MSG_RESET_SSRC;
                 } else {
                         abort();
                 }
diff --git a/src/messaging.h b/src/messaging.h
index a251fffee..806b48378 100644
--- a/src/messaging.h
+++ b/src/messaging.h
@@ -48,6 +48,7 @@ enum msg_sender_type {
         SENDER_MSG_PAUSE,
         SENDER_MSG_CHANGE_FEC,
         SENDER_MSG_QUERY_VIDEO_MODE,
+        SENDER_MSG_RESET_SSRC,
 };
 
 struct msg_sender {
diff --git a/src/video_rxtx/rtp.cpp b/src/video_rxtx/rtp.cpp
index db0a136db..668e03f9f 100644
--- a/src/video_rxtx/rtp.cpp
+++ b/src/video_rxtx/rtp.cpp
@@ -156,6 +156,26 @@ struct response *rtp_video_rxtx::process_message(struct msg_sender *msg)
                                 return new_response(RESPONSE_OK, oss.str().c_str());
                         }
                         break;
+                case SENDER_MSG_RESET_SSRC:
+                        {
+                                lock_guard<mutex> lock(m_network_devices_lock);
+                                uint32_t old_ssrc = rtp_my_ssrc(m_network_devices[0]);
+                                auto old_devices = m_network_devices;
+                                m_network_devices = initialize_network(m_requested_receiver.c_str(),
+                                                m_recv_port_number,
+                                                m_send_port_number, m_participants, m_ipv6,
+                                                m_requested_mcast_if);
+                                if (!m_network_devices) {
+                                        m_network_devices = old_devices;
+                                        log_msg(LOG_LEVEL_ERROR, "[control] Unable to change SSRC!\n");
+                                        return new_response(RESPONSE_INT_SERV_ERR, NULL);
+                                } else {
+                                        destroy_rtp_devices(old_devices);
+                                        log_msg(LOG_LEVEL_NOTICE, "[control] Changed SSRC from 0x%08lx to "
+                                                        "0x%08lx.\n", old_ssrc, rtp_my_ssrc(m_network_devices[0]));
+                                }
+                        }
+                        break;
         }
 
         return new_response(RESPONSE_OK, NULL);