kcp-sys

Safe bindings to the kcp transport protocol library.

Also including a high level API for connection state management and data stream handling.

Usage

1. Create the endpoint and run it.

   let mut endpoint = KcpEndpoint::new();
   endpoint.run().await;
   

2. forward the input and output to your transport layer, udp for example.

   let (input, mut output) = (endpoint.input_sender(), endpoint.output_receiver().unwrap());
   
   let udp_socket = Arc::new(UdpSocket::bind("0.0.0.0:54320").await.unwrap());
   udp_socket.connect("127.0.0.1:54321").await.unwrap();
   
   let udp = udp_socket.clone();
   tokio::spawn(async move {
       while let Some(data) = output.recv().await {
           udp.send(&data.inner()).await.unwrap();
       }
   });
   
   let udp = udp_socket.clone();
   tokio::spawn(async move {
       loop {
           let mut buf = vec![0; 1024];
           let (size, _) = udp.recv_from(&mut buf).await.unwrap();
           input
               .send(BytesMut::from(&buf[..size]).into())
               .await
               .unwrap();
       }
   });
   

3. Create a connection and send / recv data.

   let conn_id = endpoint
       .connect(Duration::from_secs(1), 0, 0, Bytes::new())
       .await
       .unwrap();
   
   let mut kcp_stream = KcpStream::new(&endpoint, conn_id).unwrap();
   kcp_stream.write_all(b"hello world").await.unwrap();
   
   let mut buf = vec![0; 64 * 1024];
   let size = kcp_stream.read(&mut buf).await.unwrap();
   
   println!("{}", String::from_utf8_lossy(&buf[..size]));
   

Tune the kcp parameters

You can tune the kcp parameters by set a config factory to the endpoint.

let mut endpoint = KcpEndpoint::new();
endpoint.set_kcp_config_factory(|conv| {
    KcpConfig::new_turbo(conv)
});