--- /dev/null
+origin: https://patches.libav.org/patch/39102/raw/
+diff --git a/libmpdemux/demux_rtp.cpp b/libmpdemux/demux_rtp.cpp
+index 018327c..4fa7efe 100644
+--- a/libmpdemux/demux_rtp.cpp
++++ b/libmpdemux/demux_rtp.cpp
+@@ -19,8 +19,6 @@
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+-#define RTSPCLIENT_SYNCHRONOUS_INTERFACE 1
+-
+ extern "C" {
+ // on MinGW, we must include windows.h before the things it conflicts
+ #ifdef __MINGW32__ // with. they are each protected from
+@@ -94,15 +92,6 @@ struct RTPState {
+
+ extern "C" char* network_username;
+ extern "C" char* network_password;
+-static char* openURL_rtsp(RTSPClient* client, char const* url) {
+- // If we were given a user name (and optional password), then use them:
+- if (network_username != NULL) {
+- char const* password = network_password == NULL ? "" : network_password;
+- return client->describeWithPassword(url, network_username, password);
+- } else {
+- return client->describeURL(url);
+- }
+-}
+
+ static char* openURL_sip(SIPClient* client, char const* url) {
+ // If we were given a user name (and optional password), then use them:
+@@ -126,6 +115,19 @@ int rtsp_transport_http = 0;
+ extern AVCodecContext *avcctx;
+ #endif
+
++static char fWatchVariableForSyncInterface;
++static char* fResultString;
++static int fResultCode;
++
++static void responseHandlerForSyncInterface(RTSPClient* rtspClient, int responseCode, char* responseString) {
++ // Set result values:
++ fResultCode = responseCode;
++ fResultString = responseString;
++
++ // Signal a break from the event loop (thereby returning from the blocking command):
++ fWatchVariableForSyncInterface = ~0;
++}
++
+ extern "C" int audio_id, video_id, dvdsub_id;
+ extern "C" demuxer_t* demux_open_rtp(demuxer_t* demuxer) {
+ Boolean success = False;
+@@ -154,13 +156,19 @@ extern "C" demuxer_t* demux_open_rtp(demuxer_t* demuxer) {
+ rtsp_transport_http = demuxer->stream->streaming_ctrl->url->port;
+ rtsp_transport_tcp = 1;
+ }
+- rtspClient = RTSPClient::createNew(*env, verbose, "MPlayer", rtsp_transport_http);
++ rtspClient = RTSPClient::createNew(*env, url, verbose, "MPlayer", rtsp_transport_http);
+ if (rtspClient == NULL) {
+ fprintf(stderr, "Failed to create RTSP client: %s\n",
+ env->getResultMsg());
+ break;
+ }
+- sdpDescription = openURL_rtsp(rtspClient, url);
++ fWatchVariableForSyncInterface = 0;
++ rtspClient->sendDescribeCommand(responseHandlerForSyncInterface);
++ env->taskScheduler().doEventLoop(&fWatchVariableForSyncInterface);
++ if (fResultCode == 0)
++ sdpDescription = fResultString;
++ else
++ delete[] fResultString;
+ } else { // SIP
+ unsigned char desiredAudioType = 0; // PCMU (use 3 for GSM)
+ sipClient = SIPClient::createNew(*env, desiredAudioType, NULL,
+@@ -244,8 +252,12 @@ extern "C" demuxer_t* demux_open_rtp(demuxer_t* demuxer) {
+
+ if (rtspClient != NULL) {
+ // Issue a RTSP "SETUP" command on the chosen subsession:
+- if (!rtspClient->setupMediaSubsession(*subsession, False,
+- rtsp_transport_tcp)) break;
++ fWatchVariableForSyncInterface = 0;
++ rtspClient->sendSetupCommand(*subsession, responseHandlerForSyncInterface, False, rtsp_transport_tcp);
++ env->taskScheduler().doEventLoop(&fWatchVariableForSyncInterface);
++ delete[] fResultString;
++ if (fResultCode != 0) break;
++
+ if (!strcmp(subsession->mediumName(), "audio"))
+ audiofound = 1;
+ if (!strcmp(subsession->mediumName(), "video"))
+@@ -256,7 +268,11 @@ extern "C" demuxer_t* demux_open_rtp(demuxer_t* demuxer) {
+
+ if (rtspClient != NULL) {
+ // Issue a RTSP aggregate "PLAY" command on the whole session:
+- if (!rtspClient->playMediaSession(*mediaSession)) break;
++ fWatchVariableForSyncInterface = 0;
++ rtspClient->sendPlayCommand(*mediaSession, responseHandlerForSyncInterface);
++ env->taskScheduler().doEventLoop(&fWatchVariableForSyncInterface);
++ delete[] fResultString;
++ if (fResultCode != 0) break;
+ } else if (sipClient != NULL) {
+ sipClient->sendACK(); // to start the stream flowing
+ }
+@@ -645,7 +661,8 @@ static void teardownRTSPorSIPSession(RTPState* rtpState) {
+ MediaSession* mediaSession = rtpState->mediaSession;
+ if (mediaSession == NULL) return;
+ if (rtpState->rtspClient != NULL) {
+- rtpState->rtspClient->teardownMediaSession(*mediaSession);
++ fWatchVariableForSyncInterface = 0;
++ rtpState->rtspClient->sendTeardownCommand(*mediaSession, NULL);
+ } else if (rtpState->sipClient != NULL) {
+ rtpState->sipClient->sendBYE();
+ }