/// <summary>
/// Start receiving data from the socket.
/// </summary>
public void Start()
{
// don't start if disposing
if (_disposing)
{
return;
}
// ensure we don't start multiple times
if (Interlocked.CompareExchange(ref _started, 1, 0) == 1)
{
// already started! can't call Start() twice.
throw new InvalidOperationException("Cannot call AsyncSocket.Start() more than once.");
}
// configure for receive
var args = SocketEventArgsCache.AllocateForReceive(OnSocketReceive);
// start a receive request and immediately check to see if the receive is already complete
// otherwise OnIOCompleted will get called when the receive is complete
if (!Socket.ReceiveAsync(args))
{
ReceiveSocketData(args);
}
}
/// <summary>
/// Complete processing a buffer of bytes read from the socket.
/// </summary>
private void CompleteReceive()
{
// ReadSocketData temporarily releases the lock (and then enters it again), so we need to ensure
// we haven't disposed in the meantime
if (_disposing)
{
_readLock.Release();
return;
}
if (_receivedBuffer.TakeItem().Length > 0)
{
_receivedBuffer.Release();
ManagerUpdate.Control.AddSingle(ProcessReceivedData);
return;
}
_receivedBuffer.Release();
// flop the processing flag
_readLock.Release();
// any bytes in the queue?
if (_receivedBuffer.TakeItem().Length > 0 && _readLock.TryTake)
{
_receivedBuffer.Release();
ManagerUpdate.Control.AddSingle(ProcessReceivedData);
return;
}
_receivedBuffer.Release();
// socket may have been closed already due to connection error.
// if not try receiving more data
if (Socket.Connected)
{
// receiveAsync returns true if the I/O operation is pending. An event will be raised upon completion.
// returns false if the I/O operation completed synchronously.
var args = SocketEventArgsCache.AllocateForReceive(OnSocketReceive);
if (!Socket.ReceiveAsync(args))
{
ReceiveSocketData(args);
}
}
else
{
if (_disposing)
{
return;
}
ProcessError("Cannot receive, socket is not connected.");
}
}