void ProxyRTSPClient::continueAfterLivenessCommand(int resultCode, Boolean serverSupportsGetParameter) {
if (resultCode != 0) {
// The periodic 'liveness' command failed, suggesting that the back-end stream is no longer alive.
// We handle this by resetting our connection state with this server. Any current clients will be closed, but
// subsequent clients will cause new RTSP "SETUP"s and "PLAY"s to get done, restarting the stream.
// Then continue by sending more "DESCRIBE" commands, to try to restore the stream.
fServerSupportsGetParameter = False; // until we learn otherwise, in response to a future "OPTIONS" command
if (resultCode < 0) {
// The 'liveness' command failed without getting a response from the server (otherwise "resultCode" would have been > 0).
// This suggests that the RTSP connection itself has failed. Print this error code, in case it's useful for debugging:
if (fVerbosityLevel > 0) {
envir() << *this << ": lost connection to server ('errno': " << -resultCode << "). Resetting...\n";
}
}
reset();
fOurServerMediaSession.resetDESCRIBEState();
setBaseURL(fOurURL); // because we'll be sending an initial "DESCRIBE" all over again
sendDESCRIBE(this);
return;
}
fServerSupportsGetParameter = serverSupportsGetParameter;
// Schedule the next 'liveness' command (i.e., to tell the back-end server that we're still alive):
scheduleLivenessCommand();
}
void ProxyRTSPClient::continueAfterDESCRIBE(char const* sdpDescription) {
if (sdpDescription != NULL) {
fOurServerMediaSession.continueAfterDESCRIBE(sdpDescription);
// Unlike most RTSP streams, there might be a long delay between this "DESCRIBE" command (to the downstream server) and the
// subsequent "SETUP"/"PLAY" - which doesn't occur until the first time that a client requests the stream.
// To prevent the proxied connection (between us and the downstream server) from timing out, we send periodic
// "OPTIONS" commands. (The usual RTCP liveness mechanism wouldn't work here, because RTCP packets don't get sent
// until after the "PLAY" command.)
scheduleLivenessCommand();
} else {
// The "DESCRIBE" command failed, most likely because the server or the stream is not yet running.
// Reschedule another "DESCRIBE" command to take place later:
scheduleDESCRIBECommand();
}
}
void ProxyRTSPClient::continueAfterOPTIONS(int resultCode) {
if (resultCode < 0) {
// The "OPTIONS" command failed without getting a response from the server (otherwise "resultCode" would have been >= 0).
// From this, we infer that the server (which had previously been running) has now failed - perhaps temporarily.
// We handle this by resetting our connection state with this server. Any current clients will have to time out, but
// subsequent clients will cause new RTSP "SETUP"s and "PLAY"s to get done, restarting the stream.
if (fVerbosityLevel > 0) {
envir() << *this << ": lost connection to server ('errno': " << -resultCode << "). Resetting...\n";
}
reset();
// Also "reset()" each of our "ProxyServerMediaSubsession"s:
ServerMediaSubsessionIterator iter(fOurServerMediaSession);
ProxyServerMediaSubsession* psmss;
while ((psmss = (ProxyServerMediaSubsession*)(iter.next())) != NULL) {
psmss->reset();
}
}
// Schedule the next RTSP "OPTIONS" command (to show client liveness):
scheduleLivenessCommand();
}
