Kill TCP sockets in 2 stages to fix a race condition during socket closure

limelight-common/ControlStream.c

@@ -392,20 +392,24 @@ int stopControlStream(void) {
     LbqSignalQueueShutdown(&invalidReferenceFrameTuples);
     PltSetEvent(&invalidateRefFramesEvent);
     
+    if (ctlSock != INVALID_SOCKET) {
+        shutdownSocket(ctlSock);
+    }
+    
     PltInterruptThread(&lossStatsThread);
     PltInterruptThread(&invalidateRefFramesThread);
 
-    if (ctlSock != INVALID_SOCKET) {
-        closeSocket(ctlSock);
-        ctlSock = INVALID_SOCKET;
-    }
-
     PltJoinThread(&lossStatsThread);
     PltJoinThread(&invalidateRefFramesThread);
 
     PltCloseThread(&lossStatsThread);
     PltCloseThread(&invalidateRefFramesThread);
     
+    if (ctlSock != INVALID_SOCKET) {
+        closeSocket(ctlSock);
+        ctlSock = INVALID_SOCKET;
+    }
+
     return 0;
 }
 

limelight-common/InputStream.c

@@ -294,13 +294,17 @@ int stopInputStream(void) {
     PltInterruptThread(&inputSendThread);
 
     if (inputSock != INVALID_SOCKET) {
-        closeSocket(inputSock);
-        inputSock = INVALID_SOCKET;
+        shutdownSocket(inputSock);
     }
 
     PltJoinThread(&inputSendThread);
     PltCloseThread(&inputSendThread);
     
+    if (inputSock != INVALID_SOCKET) {
+        closeSocket(inputSock);
+        inputSock = INVALID_SOCKET;
+    }
+
     return 0;
 }
 

limelight-common/PlatformSockets.c

@@ -21,12 +21,13 @@ void addrToUrlSafeString(struct sockaddr_storage* addr, char* string)
     }
 }
 
-void closeSocket(SOCKET s) {
+void shutdownSocket(SOCKET s) {
     // Calling shutdown() prior to close wakes up callers
     // blocked in connect(), recv(), and friends.
     shutdown(s, SHUT_RDWR);
+}
 
-    // Now close the socket fd
+void closeSocket(SOCKET s) {
 #ifdef _WIN32
     closesocket(s);
 #else

limelight-common/PlatformSockets.h

@@ -43,4 +43,5 @@ void addrToUrlSafeString(struct sockaddr_storage* addr, char* string);
 SOCKET connectTcpSocket(struct sockaddr_storage* dstaddr, SOCKADDR_LEN addrlen, unsigned short port);
 SOCKET bindUdpSocket(int addrfamily, int bufferSize);
 int enableNoDelay(SOCKET s);
+void shutdownSocket(SOCKET s);
 void closeSocket(SOCKET s);

limelight-common/RtspConnection.c

@@ -144,11 +144,11 @@ Exit:
     return ret;
 }
 
-// Terminate the RTSP Handshake process by closing the socket
+// Terminate the RTSP Handshake process by shutting down the socket.
+// The thread waiting on RTSP will close the socket.
 void terminateRtspHandshake(void) {
     if (sock != INVALID_SOCKET) {
-        closeSocket(sock);
-        sock = INVALID_SOCKET;
+        shutdownSocket(sock);
     }
 }