private void HandleTcpClientAccepted(IAsyncResult ar)
{
if (IsRunning)
{
TcpListener tcpListener = (TcpListener)ar.AsyncState;
TcpClient tcpClient = tcpListener.EndAcceptTcpClient(ar);
if (!tcpClient.Connected)
{
return;
}
byte[] buffer = new byte[tcpClient.ReceiveBufferSize];
// add client connection to cache
TcpClientState tcpClientState = new TcpClientState(tcpClient, buffer);
lock (this._clients)
{
string clientKey = tcpClientState.TcpClient.Client.RemoteEndPoint.ToString();
this._clients.AddOrUpdate(clientKey, tcpClientState, (c, t) => { return(tcpClientState); });
RaiseClientConnected(tcpClientState);
}
// begin to read data
NetworkStream networkStream = tcpClientState.NetworkStream;
ContinueReadBuffer(tcpClientState, networkStream);
// keep listening to accept next connection
ContinueAcceptTcpClient(tcpListener);
}
}
private void HandleDatagramReceived(IAsyncResult ar)
{
if (!IsRunning)
{
return;
}
try
{
TcpClientState tcpClientState = (TcpClientState)ar.AsyncState;
if (!tcpClientState.TcpClient.Connected)
{
return;
}
NetworkStream networkStream = tcpClientState.NetworkStream;
int numberOfReadBytes = 0;
try
{
// if the remote host has shutdown its connection,
// read will immediately return with zero bytes.
numberOfReadBytes = networkStream.EndRead(ar);
}
catch (Exception ex)
{
Logger.Error("", ex);
numberOfReadBytes = 0;
}
if (numberOfReadBytes == 0)
{
// connection has been closed
string tcpClientKey = tcpClientState.TcpClient.Client.RemoteEndPoint.ToString();
_clients.TryRemove(tcpClientKey, out TcpClientState internalClientToBeThrowAway);
RaiseClientDisconnected(tcpClientState.TcpClient);
return;
}
// received byte and trigger event notification
byte[] receivedBytes = new byte[numberOfReadBytes];
Buffer.BlockCopy(
tcpClientState.Buffer,
0,
receivedBytes,
0,
numberOfReadBytes);
RaiseDatagramReceived(tcpClientState.TcpClient, receivedBytes);
RaisePlaintextReceived(tcpClientState.TcpClient, receivedBytes);
// continue listening for tcp datagram packets
ContinueReadBuffer(tcpClientState, networkStream);
}
catch (InvalidOperationException ex)
{
Logger.Error("", ex);
}
}
private void ContinueReadBuffer(TcpClientState tcpClientState, NetworkStream networkStream)
{
try
{
networkStream.BeginRead(
tcpClientState.Buffer,
0,
tcpClientState.Buffer.Length,
HandleDatagramReceived,
tcpClientState);
}
catch (ObjectDisposedException ex)
{
Logger.Error("", ex);
}
}
private void RaiseClientConnected(TcpClientState tcpClientState)
{
ClientConnected?.Invoke(this, new TcpClientConnectedEventArgs(tcpClientState.TcpClient));
}