private async Task HandleRequestAsync()
{
while (true)
{
#if ModBusDebug
Debug.WriteLine($"Begin reading header from Master at IP: {EndPoint}");
#endif
int readBytes = await Stream.ReadAsync(_mbapHeader, 0, 6).ConfigureAwait(false);
if (readBytes == 0)
{
#if ModBusDebug
Debug.WriteLine($"0 bytes read, Master at {EndPoint} has closed Socket connection.");
#endif
ModbusMasterTcpConnectionClosed?.Invoke(this, new TcpConnectionEventArgs(EndPoint));
return;
}
ushort frameLength = (ushort)IPAddress.HostToNetworkOrder(BitConverter.ToInt16(_mbapHeader, 4));
#if ModBusDebug
Debug.WriteLine($"Master at {EndPoint} sent header: \"{string.Join(", ", _mbapHeader)}\" with {frameLength} bytes in PDU");
#endif
_messageFrame = new byte[frameLength];
readBytes = await Stream.ReadAsync(_messageFrame, 0, frameLength).ConfigureAwait(false);
if (readBytes == 0)
{
#if ModBusDebug
Debug.WriteLine($"0 bytes read, Master at {EndPoint} has closed Socket connection.");
#endif
ModbusMasterTcpConnectionClosed?.Invoke(this, new TcpConnectionEventArgs(EndPoint));
return;
}
#if ModBusDebug
Debug.WriteLine($"Read frame from Master at {EndPoint} completed {readBytes} bytes");
#endif
byte[] frame = _mbapHeader.Concat(_messageFrame).ToArray();
#if ModBusDebug
Debug.WriteLine($"RX from Master at {EndPoint}: {string.Join(", ", frame)}");
#endif
var request = ModbusMessageFactory.CreateModbusRequest(_messageFrame);
request.TransactionId = (ushort)IPAddress.NetworkToHostOrder(BitConverter.ToInt16(frame, 0));
// perform action and build response
IModbusMessage response = _slave.ApplyRequest(request);
response.TransactionId = request.TransactionId;
// write response
byte[] responseFrame = Transport.BuildMessageFrame(response);
#if ModBusDebug
Debug.WriteLine($"TX to Master at {EndPoint}: {string.Join(", ", responseFrame)}");
#endif
await Stream.WriteAsync(responseFrame, 0, responseFrame.Length).ConfigureAwait(false);
}
}
private async Task HandleRequestAsync()
{
var serialTransport = (IModbusSerialTransport)Transport;
while (true)
{
try
{
// read request and build message
byte[] frame = serialTransport.ReadRequest();
//Create the request
IModbusMessage request = _modbusFactory.CreateModbusRequest(frame);
//Check the message
if (serialTransport.CheckFrame && !serialTransport.ChecksumsMatch(request, frame))
{
string msg = $"Checksums failed to match {string.Join(", ", request.MessageFrame)} != {string.Join(", ", frame)}.";
//Logger.Warning(msg);
throw new IOException(msg);
}
//Apply the request
// TODO: почистить класс и предусмотреть броадкаст request.SlaveAddress ==0
IModbusMessage response = _slaveNetwork.GetSlave(request.SlaveAddress)
.ApplyRequest(request);
if (response == null)
{
serialTransport.IgnoreResponse();
}
else
{
Transport.Write(response);
}
}
catch (IOException /*ioe*/)
{
//Logger.Warning($"IO Exception encountered while listening for requests - {ioe.Message}");
serialTransport.DiscardInBuffer();
ModbusMasterTcpConnectionClosed?.Invoke(this, new TcpConnectionEventArgs(EndPoint));
}
catch (TimeoutException /*te*/)
{
//Logger.Trace($"Timeout Exception encountered while listening for requests - {te.Message}");
serialTransport.DiscardInBuffer();
}
catch (InvalidOperationException)
{
// when the underlying transport is disposed
break;
}
catch (Exception /*ex*/)
{
//Logger.Error($"{GetType()}: {ex.Message}");
serialTransport.DiscardInBuffer();
}
/* // OLD CODE
* // //Logger.Debug($"Begin reading header from Master at IP: {EndPoint}");
*
* int readBytes = await Stream.ReadAsync(_mbapHeader, 0, 6).ConfigureAwait(false);
* if (readBytes == 0)
* {
* //Logger.Debug($"0 bytes read, Master at {EndPoint} has closed Socket connection.");
* ModbusMasterTcpConnectionClosed?.Invoke(this, new TcpConnectionEventArgs(EndPoint));
* return;
* }
*
* ushort frameLength = (ushort)IPAddress.HostToNetworkOrder(BitConverter.ToInt16(_mbapHeader, 4));
* //Logger.Debug($"Master at {EndPoint} sent header: \"{string.Join(", ", _mbapHeader)}\" with {frameLength} bytes in PDU");
*
* _messageFrame = new byte[frameLength];
* readBytes = await Stream.ReadAsync(_messageFrame, 0, frameLength).ConfigureAwait(false);
* if (readBytes == 0)
* {
* //Logger.Debug($"0 bytes read, Master at {EndPoint} has closed Socket connection.");
* ModbusMasterTcpConnectionClosed?.Invoke(this, new TcpConnectionEventArgs(EndPoint));
* return;
* }
*
* //Logger.Debug($"Read frame from Master at {EndPoint} completed {readBytes} bytes");
* byte[] frame = _mbapHeader.Concat(_messageFrame).ToArray();
* //Logger.Trace($"RX from Master at {EndPoint}: {string.Join(", ", frame)}");
*
* var request = _modbusFactory.CreateModbusRequest(_messageFrame);
* request.TransactionId = (ushort)IPAddress.NetworkToHostOrder(BitConverter.ToInt16(frame, 0));
*
* IModbusSlave slave = _slaveNetwork.GetSlave(request.SlaveAddress);
*
* if (slave != null)
* {
* //TODO: Determine if this is appropriate
*
* // perform action and build response
* IModbusMessage response = slave.ApplyRequest(request);
* response.TransactionId = request.TransactionId;
*
* // write response
* byte[] responseFrame = Transport.BuildMessageFrame(response);
* //Logger.Information($"TX to Master at {EndPoint}: {string.Join(", ", responseFrame)}");
* await Stream.WriteAsync(responseFrame, 0, responseFrame.Length).ConfigureAwait(false);
* }
*/
}
}
