refactored RTCEngine

crates/livekit-webrtc/libwebrtc-sys/include/livekit/data_channel.h

@@ -24,10 +24,10 @@ class DataChannel {
 
   void register_observer(NativeDataChannelObserver& observer);
   void unregister_observer();
-  bool send(const DataBuffer& buffer);
+  bool send(const DataBuffer& buffer) const;
   rust::String label() const;
   DataState state() const;
-  void close();
+  void close() const;
 
  private:
   std::shared_ptr<RTCRuntime> rtc_runtime_;

crates/livekit-webrtc/libwebrtc-sys/src/data_channel.cpp

@@ -24,7 +24,7 @@ void DataChannel::unregister_observer() {
   data_channel_->UnregisterObserver();
 }
 
-bool DataChannel::send(const DataBuffer& buffer) {
+bool DataChannel::send(const DataBuffer& buffer) const {
   return data_channel_->Send(webrtc::DataBuffer{
       rtc::CopyOnWriteBuffer(buffer.ptr, buffer.len), buffer.binary});
 }
@@ -37,7 +37,7 @@ DataState DataChannel::state() const {
   return static_cast<DataState>(data_channel_->state());
 }
 
-void DataChannel::close() {
+void DataChannel::close() const {
   return data_channel_->Close();
 }
 

crates/livekit-webrtc/libwebrtc-sys/src/data_channel.rs

@@ -68,10 +68,10 @@ pub mod ffi {
         );
 
         fn unregister_observer(self: Pin<&mut DataChannel>);
-        fn send(self: Pin<&mut DataChannel>, data: &DataBuffer) -> bool;
+        fn send(self:  &DataChannel, data: &DataBuffer) -> bool;
         fn label(self: &DataChannel) -> String;
         fn state(self: &DataChannel) -> DataState;
-        fn close(self: Pin<&mut DataChannel>);
+        fn close(self: &DataChannel);
 
         fn create_data_channel_init(init: DataChannelInit) -> UniquePtr<NativeDataChannelInit>;
         fn create_native_data_channel_observer(

crates/livekit-webrtc/src/data_channel.rs

@@ -58,7 +58,7 @@ impl DataChannel {
         dc
     }
 
-    pub fn send(&mut self, data: &[u8], binary: bool) -> Result<(), DataSendError> {
+    pub fn send(&self, data: &[u8], binary: bool) -> Result<(), DataSendError> {
         let buffer = sys_dc::ffi::DataBuffer {
             ptr: data.as_ptr(),
             len: data.len(),
@@ -66,7 +66,6 @@ impl DataChannel {
         };
 
         self.cxx_handle
-            .pin_mut()
             .send(&buffer)
             .then_some(())
             .ok_or(DataSendError {})
@@ -80,8 +79,8 @@ impl DataChannel {
         self.cxx_handle.state()
     }
 
-    pub fn close(&mut self) {
-        self.cxx_handle.pin_mut().close();
+    pub fn close(&self) {
+        self.cxx_handle.close();
     }
 
     pub fn on_state_change(&mut self, handler: OnStateChangeHandler) {