// This is called after the byte array segments have been successfully sent to the connected socket
private void BeginSendCallback(object sender, SocketAsyncEventArgs args)
{
try
{
if (args.BytesTransferred <= 0)
{
DnlDebugger.LogMessage("0 bytes transferred in the last send operation", true);
return;
}
// Another temp holder
DnlUdpSendSegment segment;
// If theres more segments
if ((segment = sendSegments.Peek()) != null)
{
// If the current segment has been advanced
if (segment.Advance(args.BytesTransferred))
{
sendSegments.Dequeue();
}
// Recursively send the data if there's more segments to send
if (sendSegments.Count > 0)
{
BeginSend();
}
else
{
// Set this thread's sending state to idle
isSending = 0;
}
}
}
catch (Exception e)
{
DnlDebugger.LogMessage("Caught exception in EndSendCallback: " + e.Message + " | " + e.TargetSite.ToString(), true);
}
finally
{
args.Dispose();
}
}
public void Stop()
{
if (!IsListening)
{
return;
}
IsListening = false;
try
{
Socket.Shutdown(SocketShutdown.Both);
}
catch (Exception e)
{
DnlDebugger.LogMessage("Exception caught when trying to shut down listener: " + e.Message, true);
}
finally
{
Socket.Close();
}
}
private void BeginReceiveCallback(object sender, SocketAsyncEventArgs args)
{
if (!IsListening)
{
return;
}
try
{
// No bytes been transferred from this async operation
if (args.BytesTransferred <= 0)
{
DnlDebugger.LogMessage("0 bytes transferred from receive operation: " + args.RemoteEndPoint.ToString() + " | " + args.BytesTransferred, true);
}
else
{
ushort protocolId;
ushort operationCode;
// Parse and validate protocol id and operation code
if ((protocolId = unchecked (BitConverter.ToUInt16(args.Buffer, 0))) != ProtocolId)
{
throw new Exception("Received datagram with different protocol id then expected. Either set your protocol id or ensure network traffic is from known clients.");
}
if (!OperationCodes.ReceivePacket.ContainsKey(operationCode = unchecked (BitConverter.ToUInt16(args.Buffer, 2))))
{
throw new Exception("Received datagram with different unregistered operation code. Either register your operation packet handler or ensure network traffic is from known clients.");
}
int payloadLength = args.BytesTransferred - (sizeof(ushort) * 2);
byte[] payload = new byte[payloadLength];
// Parse payload from datagram
Buffer.BlockCopy(args.Buffer, 4, payload, 0, payloadLength);
// Parse ip and port from endpoint string
string[] systemAddress = !string.IsNullOrEmpty(args.RemoteEndPoint.ToString()) ?
args.RemoteEndPoint.ToString().Split(':') :
throw new Exception("Internal issue trying to parse remote endpoint from incoming datagram. Contact support");
// Invoke the on received event
OnDatagramReceived?.Invoke(this, new DatagramReceivedEventArgs(
systemAddress[0],
int.Parse(systemAddress[1]),
protocolId,
operationCode,
payload,
payload.Length,
DateTime.Now));
}
}
catch (Exception e)
{
DnlDebugger.LogMessage("Caught exception in EndReceive: " + e.Message + " | " + e.TargetSite.ToString(), true);
}
finally
{
args.Dispose();
BeginReceive();
}
}
