Add PeerConnection Media Handler Support

include/rtc/peerconnection.hpp

@@ -92,6 +92,9 @@ public:
 	void setRemoteDescription(Description description);
 	void addRemoteCandidate(Candidate candidate);
 
+	void setMediaHandler(shared_ptr<MediaHandler> handler);
+	shared_ptr<MediaHandler> getMediaHandler();
+
 	[[nodiscard]] shared_ptr<DataChannel> createDataChannel(string label, DataChannelInit init = {});
 	void onDataChannel(std::function<void(std::shared_ptr<DataChannel> dataChannel)> callback);
 

src/impl/peerconnection.cpp

@@ -349,7 +349,8 @@ void PeerConnection::closeTransports() {
 	if (!changeState(State::Closed))
 		return; // already closed
 
-	// Reset callbacks now that state is changed
+	// Reset intercceptor and callbacks now that state is changed
+	setMediaHandler(nullptr);
 	resetCallbacks();
 
 	// Pass the pointers to a thread, allowing to terminate a transport from its own thread
@@ -475,6 +476,14 @@ void PeerConnection::forwardMedia(message_ptr message) {
 	if (!message)
 		return;
 
+	auto handler = getMediaHandler();
+
+	if (handler) {
+		message = handler->incoming(message);
+		if (!message)
+			return;
+	}
+
 	// Browsers like to compound their packets with a random SSRC.
 	// we have to do this monstrosity to distribute the report blocks
 	if (message->type == Message::Control) {
@@ -1066,6 +1075,18 @@ string PeerConnection::localBundleMid() const {
 	return mLocalDescription ? mLocalDescription->bundleMid() : "0";
 }
 
+void PeerConnection::setMediaHandler(shared_ptr<MediaHandler> handler) {
+	std::unique_lock lock(mMediaHandlerMutex);
+	if (mMediaHandler)
+		mMediaHandler->onOutgoing(nullptr);
+	mMediaHandler = handler;
+}
+
+shared_ptr<MediaHandler> PeerConnection::getMediaHandler() {
+	std::shared_lock lock(mMediaHandlerMutex);
+	return mMediaHandler;
+}
+
 void PeerConnection::triggerDataChannel(weak_ptr<DataChannel> weakDataChannel) {
 	auto dataChannel = weakDataChannel.lock();
 	if (dataChannel) {

src/impl/peerconnection.hpp

@@ -89,6 +89,9 @@ struct PeerConnection : std::enable_shared_from_this<PeerConnection> {
 	void processRemoteCandidate(Candidate candidate);
 	string localBundleMid() const;
 
+	void setMediaHandler(shared_ptr<MediaHandler> handler);
+	shared_ptr<MediaHandler> getMediaHandler();
+
 	void triggerDataChannel(weak_ptr<DataChannel> weakDataChannel);
 	void triggerTrack(weak_ptr<Track> weakTrack);
 
@@ -135,6 +138,10 @@ private:
 	optional<Description> mCurrentLocalDescription;
 	mutable std::mutex mLocalDescriptionMutex, mRemoteDescriptionMutex;
 
+	shared_ptr<MediaHandler> mMediaHandler;
+
+	mutable std::shared_mutex mMediaHandlerMutex;
+
 	shared_ptr<IceTransport> mIceTransport;
 	shared_ptr<DtlsTransport> mDtlsTransport;
 	shared_ptr<SctpTransport> mSctpTransport;

src/peerconnection.cpp

@@ -249,6 +249,12 @@ void PeerConnection::addRemoteCandidate(Candidate candidate) {
 	impl()->processRemoteCandidate(std::move(candidate));
 }
 
+void PeerConnection::setMediaHandler(shared_ptr<MediaHandler> handler) {
+	impl()->setMediaHandler(std::move(handler));
+};
+
+shared_ptr<MediaHandler> PeerConnection::getMediaHandler() { return impl()->getMediaHandler(); };
+
 optional<string> PeerConnection::localAddress() const {
 	auto iceTransport = impl()->getIceTransport();
 	return iceTransport ? iceTransport->getLocalAddress() : nullopt;