From b46e06fcf1b289bb6a3b2307c10e1a7274c5f3b5 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Fri, 1 May 2020 19:25:24 -0700
Subject: [PATCH] Terminate the connection if video isn't received for 10
 seconds

---
 src/ControlStream.c |  2 +-
 src/Limelight.h     | 11 +++++++++++
 src/VideoStream.c   | 12 ++++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/ControlStream.c b/src/ControlStream.c
index 0f8957f..d34a2ae 100644
--- a/src/ControlStream.c
+++ b/src/ControlStream.c
@@ -564,7 +564,7 @@ static void controlReceiveThreadFunc(void* context) {
                 // SERVER_TERMINATED_INTENDED
                 if (terminationReason == 0x0100) {
                     // Pass error code 0 to notify the client that this was not an error
-                    terminationErrorCode = 0;
+                    terminationErrorCode = ML_ERROR_GRACEFUL_TERMINATION;
                 }
                 else {
                     // Otherwise pass the reason unmodified
diff --git a/src/Limelight.h b/src/Limelight.h
index d2053b5..a76df91 100644
--- a/src/Limelight.h
+++ b/src/Limelight.h
@@ -352,6 +352,17 @@ typedef void(*ConnListenerConnectionStarted)(void);
 // to LiStopConnection() or LiInterruptConnection().
 typedef void(*ConnListenerConnectionTerminated)(int errorCode);
 
+// This error code is passed to ConnListenerConnectionTerminated() when the stream
+// is being gracefully terminated by the host. It usually means the app on the host
+// PC has exited.
+#define ML_ERROR_GRACEFUL_TERMINATION 0
+
+// This error is passed to ConnListenerConnectionTerminated() if no video data
+// was ever received for this connection after waiting several seconds. It likely
+// indicates a problem with traffic on UDP 47998 due to missing or incorrect
+// firewall or port forwarding rules.
+#define ML_ERROR_NO_VIDEO_TRAFFIC -100
+
 // This callback is invoked to log debug message
 typedef void(*ConnListenerLogMessage)(const char* format, ...);
 
diff --git a/src/VideoStream.c b/src/VideoStream.c
index c557b71..856de60 100644
--- a/src/VideoStream.c
+++ b/src/VideoStream.c
@@ -75,6 +75,7 @@ static void ReceiveThreadProc(void* context) {
     char* buffer;
     int queueStatus;
     int useSelect;
+    int waitingForVideoMs;
 
     receiveSize = StreamConfig.packetSize + MAX_RTP_HEADER_SIZE;
     bufferSize = receiveSize + sizeof(RTPFEC_QUEUE_ENTRY);
@@ -89,6 +90,7 @@ static void ReceiveThreadProc(void* context) {
         useSelect = 0;
     }
 
+    waitingForVideoMs = 0;
     while (!PltIsThreadInterrupted(&receiveThread)) {
         PRTP_PACKET packet;
 
@@ -108,6 +110,16 @@ static void ReceiveThreadProc(void* context) {
             break;
         }
         else if  (err == 0) {
+            if (!receivedDataFromPeer) {
+                // If we wait many seconds without ever receiving a video packet,
+                // assume something is broken and terminate the connection.
+                waitingForVideoMs += UDP_RECV_POLL_TIMEOUT_MS;
+                if (waitingForVideoMs >= FIRST_FRAME_TIMEOUT_SEC * 1000) {
+                    ListenerCallbacks.connectionTerminated(ML_ERROR_NO_VIDEO_TRAFFIC);
+                    break;
+                }
+            }
+            
             // Receive timed out; try again
             continue;
         }