static void UdpPingThreadProc(void* context) {
// Ping in ASCII
char pingData[] = { 0x50, 0x49, 0x4E, 0x47 };
struct sockaddr_in6 saddr;
SOCK_RET err;
memcpy(&saddr, &RemoteAddr, sizeof(saddr));
saddr.sin6_port = htons(RTP_PORT);
// Send PING every second until we get data back then every 5 seconds after that.
while (!PltIsThreadInterrupted(&udpPingThread)) {
err = sendto(rtpSocket, pingData, sizeof(pingData), 0, (struct sockaddr*)&saddr, RemoteAddrLen);
if (err != sizeof(pingData)) {
Limelog("Audio Ping: sendto() failed: %d\n", (int)LastSocketError());
ListenerCallbacks.connectionTerminated(LastSocketFail());
return;
}
// Send less frequently if we've received data from our peer
if (receivedDataFromPeer) {
PltSleepMsInterruptible(&udpPingThread, 5000);
}
else {
PltSleepMsInterruptible(&udpPingThread, 1000);
}
}
}
/* Starts the control stream */
int startControlStream(void) {
int err;
ctlSock = connectTcpSocket(&RemoteAddr, RemoteAddrLen, 47995);
if (ctlSock == INVALID_SOCKET) {
return LastSocketFail();
}
enableNoDelay(ctlSock);
// Send START A
if (!sendMessageAndDiscardReply(packetTypes[IDX_START_A],
payloadLengths[IDX_START_A],
preconstructedPayloads[IDX_START_A])) {
Limelog("Start A failed: %d\n", (int)LastSocketError());
return LastSocketFail();
}
// Send START B
if (!sendMessageAndDiscardReply(packetTypes[IDX_START_B],
payloadLengths[IDX_START_B],
preconstructedPayloads[IDX_START_B])) {
Limelog("Start B failed: %d\n", (int)LastSocketError());
return LastSocketFail();
}
err = PltCreateThread(lossStatsThreadFunc, NULL, &lossStatsThread);
if (err != 0) {
return err;
}
err = PltCreateThread(resyncThreadFunc, NULL, &resyncThread);
if (err != 0) {
return err;
}
return 0;
}
/* Begin the input stream */
int startInputStream(void) {
int err;
inputSock = connectTcpSocket(&RemoteAddr, RemoteAddrLen, 35043);
if (inputSock == INVALID_SOCKET) {
return LastSocketFail();
}
enableNoDelay(inputSock);
err = PltCreateThread(inputSendThreadProc, NULL, &inputSendThread);
if (err != 0) {
return err;
}
return err;
}
int startAudioStream(void* audioContext, int arFlags) {
int err;
POPUS_MULTISTREAM_CONFIGURATION chosenConfig;
if (StreamConfig.audioConfiguration == AUDIO_CONFIGURATION_STEREO) {
chosenConfig = &opusStereoConfig;
}
else if (StreamConfig.audioConfiguration == AUDIO_CONFIGURATION_51_SURROUND) {
if (HighQualitySurroundEnabled) {
chosenConfig = &opus51HighSurroundConfig;
}
else {
chosenConfig = &opus51SurroundConfig;
}
}
else {
Limelog("Invalid audio configuration: %d\n", StreamConfig.audioConfiguration);
return -1;
}
err = AudioCallbacks.init(StreamConfig.audioConfiguration, chosenConfig, audioContext, arFlags);
if (err != 0) {
return err;
}
rtpSocket = bindUdpSocket(RemoteAddr.ss_family, RTP_RECV_BUFFER);
if (rtpSocket == INVALID_SOCKET) {
err = LastSocketFail();
AudioCallbacks.cleanup();
return err;
}
AudioCallbacks.start();
err = PltCreateThread(ReceiveThreadProc, NULL, &receiveThread);
if (err != 0) {
AudioCallbacks.stop();
closeSocket(rtpSocket);
AudioCallbacks.cleanup();
return err;
}
if ((AudioCallbacks.capabilities & CAPABILITY_DIRECT_SUBMIT) == 0) {
err = PltCreateThread(DecoderThreadProc, NULL, &decoderThread);
if (err != 0) {
AudioCallbacks.stop();
PltInterruptThread(&receiveThread);
PltJoinThread(&receiveThread);
PltCloseThread(&receiveThread);
closeSocket(rtpSocket);
AudioCallbacks.cleanup();
return err;
}
}
// Don't start pinging (which will cause GFE to start sending us traffic)
// until everything else is started. Otherwise we could accumulate a
// bunch of audio packets in the socket receive buffer while our audio
// backend is starting up and create audio latency.
err = PltCreateThread(UdpPingThreadProc, NULL, &udpPingThread);
if (err != 0) {
AudioCallbacks.stop();
PltInterruptThread(&receiveThread);
if ((AudioCallbacks.capabilities & CAPABILITY_DIRECT_SUBMIT) == 0) {
// Signal threads waiting on the LBQ
LbqSignalQueueShutdown(&packetQueue);
PltInterruptThread(&decoderThread);
}
PltJoinThread(&receiveThread);
if ((AudioCallbacks.capabilities & CAPABILITY_DIRECT_SUBMIT) == 0) {
PltJoinThread(&decoderThread);
}
PltCloseThread(&receiveThread);
if ((AudioCallbacks.capabilities & CAPABILITY_DIRECT_SUBMIT) == 0) {
PltCloseThread(&decoderThread);
}
closeSocket(rtpSocket);
AudioCallbacks.cleanup();
return err;
}
return 0;
}
static void ReceiveThreadProc(void* context) {
PRTP_PACKET rtp;
PQUEUED_AUDIO_PACKET packet;
int queueStatus;
int useSelect;
int packetsToDrop = 100;
packet = NULL;
if (setNonFatalRecvTimeoutMs(rtpSocket, UDP_RECV_POLL_TIMEOUT_MS) < 0) {
// SO_RCVTIMEO failed, so use select() to wait
useSelect = 1;
}
else {
// SO_RCVTIMEO timeout set for recv()
useSelect = 0;
}
while (!PltIsThreadInterrupted(&receiveThread)) {
if (packet == NULL) {
packet = (PQUEUED_AUDIO_PACKET)malloc(sizeof(*packet));
if (packet == NULL) {
Limelog("Audio Receive: malloc() failed\n");
ListenerCallbacks.connectionTerminated(-1);
break;
}
}
packet->size = recvUdpSocket(rtpSocket, &packet->data[0], MAX_PACKET_SIZE, useSelect);
if (packet->size < 0) {
Limelog("Audio Receive: recvUdpSocket() failed: %d\n", (int)LastSocketError());
ListenerCallbacks.connectionTerminated(LastSocketFail());
break;
}
else if (packet->size == 0) {
// Receive timed out; try again
// If we hit this path, there are no queued audio packets on the host PC,
// so we don't need to drop anything.
packetsToDrop = 0;
continue;
}
if (packet->size < sizeof(RTP_PACKET)) {
// Runt packet
continue;
}
rtp = (PRTP_PACKET)&packet->data[0];
if (rtp->packetType != 97) {
// Not audio
continue;
}
// We've received data, so we can stop sending our ping packets
// as quickly, since we're now just keeping the NAT session open.
receivedDataFromPeer = 1;
// GFE accumulates audio samples before we are ready to receive them,
// so we will drop the first 100 packets to avoid accumulating latency
// by sending audio frames to the player faster than they can be played.
if (packetsToDrop > 0) {
packetsToDrop--;
continue;
}
// RTP sequence number must be in host order for the RTP queue
rtp->sequenceNumber = htons(rtp->sequenceNumber);
queueStatus = RtpqAddPacket(&rtpReorderQueue, (PRTP_PACKET)packet, &packet->q.rentry);
if (RTPQ_HANDLE_NOW(queueStatus)) {
if ((AudioCallbacks.capabilities & CAPABILITY_DIRECT_SUBMIT) == 0) {
if (!queuePacketToLbq(&packet)) {
// An exit signal was received
break;
}
}
else {
decodeInputData(packet);
}
}
else {
if (RTPQ_PACKET_CONSUMED(queueStatus)) {
// The queue consumed our packet, so we must allocate a new one
packet = NULL;
}
if (RTPQ_PACKET_READY(queueStatus)) {
// If packets are ready, pull them and send them to the decoder
while ((packet = (PQUEUED_AUDIO_PACKET)RtpqGetQueuedPacket(&rtpReorderQueue)) != NULL) {
if ((AudioCallbacks.capabilities & CAPABILITY_DIRECT_SUBMIT) == 0) {
if (!queuePacketToLbq(&packet)) {
// An exit signal was received
break;
}
}
else {
decodeInputData(packet);
free(packet);
}
}
// Break on exit
if (packet != NULL) {
break;
}
}
}
}
if (packet != NULL) {
free(packet);
}
}
SOCKET connectTcpSocket(struct sockaddr_storage* dstaddr, SOCKADDR_LEN addrlen, unsigned short port, int timeoutSec) {
SOCKET s;
struct sockaddr_in6 addr;
int err;
#if defined(LC_DARWIN) || defined(FIONBIO)
int val;
#endif
s = socket(dstaddr->ss_family, SOCK_STREAM, IPPROTO_TCP);
if (s == INVALID_SOCKET) {
Limelog("socket() failed: %d\n", (int)LastSocketError());
return INVALID_SOCKET;
}
#ifdef LC_DARWIN
// Disable SIGPIPE on iOS
val = 1;
setsockopt(s, SOL_SOCKET, SO_NOSIGPIPE, (char*)&val, sizeof(val));
#endif
#ifdef FIONBIO
// Enable non-blocking I/O for connect timeout support
val = 1;
ioctlsocket(s, FIONBIO, &val);
#endif
// Start connection
memcpy(&addr, dstaddr, sizeof(addr));
addr.sin6_port = htons(port);
err = connect(s, (struct sockaddr*) &addr, addrlen);
if (err < 0) {
err = (int)LastSocketError();
}
#ifdef FIONBIO
{
struct fd_set writefds, exceptfds;
struct timeval tv;
FD_ZERO(&writefds);
FD_ZERO(&exceptfds);
FD_SET(s, &writefds);
FD_SET(s, &exceptfds);
tv.tv_sec = timeoutSec;
tv.tv_usec = 0;
// Wait for the connection to complete or the timeout to elapse
err = select(s + 1, NULL, &writefds, &exceptfds, &tv);
if (err < 0) {
// select() failed
err = LastSocketError();
Limelog("select() failed: %d\n", err);
closeSocket(s);
SetLastSocketError(err);
return INVALID_SOCKET;
}
else if (err == 0) {
// select() timed out
Limelog("select() timed out after %d seconds\n", timeoutSec);
closeSocket(s);
#if defined(LC_WINDOWS)
SetLastSocketError(WSAEWOULDBLOCK);
#else
SetLastSocketError(EWOULDBLOCK);
#endif
return INVALID_SOCKET;
}
else if (FD_ISSET(s, &writefds) || FD_ISSET(s, &exceptfds)) {
// The socket was signalled
SOCKADDR_LEN len = sizeof(err);
getsockopt(s, SOL_SOCKET, SO_ERROR, (char*)&err, &len);
if (err != 0 || FD_ISSET(s, &exceptfds)) {
// Get the error code
err = (err != 0) ? err : LastSocketFail();
}
}
// Disable non-blocking I/O now that the connection is established
val = 0;
ioctlsocket(s, FIONBIO, &val);
}
#endif
if (err != 0) {
Limelog("connect() failed: %d\n", err);
closeSocket(s);
SetLastSocketError(err);
return INVALID_SOCKET;
}
return s;
}