///<summary>
/// Get packet from received data.
///</summary>
///<param name="buff">
/// Received data. </param>
///<returns>
///Reply if any.
///</returns>
private byte[] GetPacket(byte[] buff)
{
GXByteBuffer receivedFrame = new GXByteBuffer(buff);
// Save position where data was. This is used if data is not sent to
// this server.
ushort offset = Reply.Data.Size;
GXDLMS.GetData(Settings, receivedFrame, Reply);
// If all data is not received yet.
if (!Reply.IsComplete)
{
return(null);
}
byte[] data;
// If client sends keepalive or get next frame request.
if ((Reply.MoreData & RequestTypes.Frame) != 0)
{
if (Frames != null && Frames.Length > FrameIndex)
{
data = Frames[FrameIndex++];
return(data);
}
FrameIndex = 0;
data = GXDLMS.SplitToHdlcFrames(Settings, Settings.KeepAlive(), null)[0];
return(data);
}
// Check is data sent to this server.
if (ConnectedServerAddress == 0 || ConnectedClientAddress == 0)
{
// Check is data send to this server.
if (!IsTarget(Settings.ServerAddress, Settings.ClientAddress))
{
Reply.Data.Size = offset;
Reply.IsComplete = false;
}
ConnectedServerAddress = Settings.ServerAddress;
ConnectedClientAddress = Settings.ClientAddress;
}
else if (Settings.ServerAddress != ConnectedServerAddress ||
Settings.ClientAddress != ConnectedClientAddress)
{
Reply.Data.Size = offset;
Reply.IsComplete = false;
}
// Clear received data.
receivedFrame.Clear();
ServerReply.Data = Reply.Data;
FrameIndex = 0;
return(null);
}
///<summary>
/// Handle received command.
///</summary>
private void HandleCommand()
{
switch (Reply.Command)
{
case Command.SetRequest:
Frames = HandleSetRequest();
break;
case Command.WriteRequest:
Frames = HandleWriteRequest();
break;
case Command.GetRequest:
Frames = HandleGetRequest();
break;
case Command.ReadRequest:
Frames = HandleReadRequest();
break;
case Command.MethodRequest:
Frames = HandleMethodRequest();
break;
case Command.Snrm:
Frames = HandleSnrmRequest();
break;
case Command.Aarq:
Frames = HandleAarqRequest();
break;
case Command.DisconnectRequest:
Frames = GenerateDisconnectRequest();
break;
default:
Debug.WriteLine("Invalid command: " + Reply.Command.ToString());
Frames = GXDLMS.SplitToHdlcFrames(Settings, (byte)FrameType.Rejected, null);
break;
}
}
///<summary>
///Generates disconnect request.
/// </summary>
///<returns>
///Disconnect request.
///</returns>
private byte[][] GenerateDisconnectRequest()
{
GXByteBuffer buff;
if (this.InterfaceType == InterfaceType.WRAPPER)
{
buff = new GXByteBuffer(2);
buff.SetUInt8(0x63);
buff.SetUInt8(0x0);
return(GXDLMS.SplitToWrapperFrames(Settings, buff));
}
else
{
buff = new GXByteBuffer(22);
buff.SetUInt8(0x81); // FromatID
buff.SetUInt8(0x80); // GroupID
buff.SetUInt8(0); // Length
buff.SetUInt8(HDLCInfo.MaxInfoTX);
buff.SetUInt8(GXCommon.GetSize(Limits.MaxInfoTX));
buff.Add(Limits.MaxInfoTX);
buff.SetUInt8(HDLCInfo.MaxInfoRX);
buff.SetUInt8(GXCommon.GetSize(Limits.MaxInfoRX));
buff.Add(Limits.MaxInfoRX);
buff.SetUInt8(HDLCInfo.WindowSizeTX);
buff.SetUInt8(GXCommon.GetSize(Limits.WindowSizeTX));
buff.Add(Limits.WindowSizeTX);
buff.SetUInt8(HDLCInfo.WindowSizeRX);
buff.SetUInt8(GXCommon.GetSize(Limits.WindowSizeRX));
buff.Add(Limits.WindowSizeRX);
int len = buff.Position - 3;
buff.SetUInt8(2, (byte)len); // Length.
}
return(GXDLMS.SplitToHdlcFrames(Settings, (byte)Command.Ua, buff));
}
///<summary>
/// Handles client request.
/// </summary>
///<param name="buff">
/// Received data from the client. </param>
///<returns>
///Response to the request. Response is null if request packet is not complete.
///</returns>
public virtual byte[] HandleRequest(byte[] buff)
{
if (buff == null || buff.Length == 0)
{
return(null);
}
if (!Initialized)
{
throw new Exception("Server not Initialized.");
}
try
{
byte[] data = GetPacket(buff);
// If all data is not received yet or message is not accepted.
if (!Reply.IsComplete)
{
return(null);
}
if (data != null)
{
return(data);
}
HandleCommand();
if (!Reply.IsMoreData)
{
Reply.Clear();
}
data = Frames[FrameIndex++];
return(data);
}
catch (Exception e)
{
// Disconnect.
Debug.WriteLine(e.ToString());
byte[] data = GXDLMS.SplitToHdlcFrames(Settings, (byte)FrameType.Rejected, null)[0];
Reset();
return(data);
}
}
///<summary>
///Parse SNRM Request. If server do not accept client empty byte array is returned.
/// </summary>
///<returns>
///Returns returned UA packet.
///</returns>
private byte[][] HandleSnrmRequest()
{
GXByteBuffer bb = new GXByteBuffer(25);
bb.SetUInt8(0x81); // FromatID
bb.SetUInt8(0x80); // GroupID
bb.SetUInt8(0); // Length
bb.SetUInt8(HDLCInfo.MaxInfoTX);
bb.SetUInt8(GXCommon.GetSize(Limits.MaxInfoTX));
bb.Add(Limits.MaxInfoTX);
bb.SetUInt8(HDLCInfo.MaxInfoRX);
bb.SetUInt8(GXCommon.GetSize(Limits.MaxInfoRX));
bb.Add(Limits.MaxInfoRX);
bb.SetUInt8(HDLCInfo.WindowSizeTX);
bb.SetUInt8(GXCommon.GetSize(Limits.WindowSizeTX));
bb.Add(Limits.WindowSizeTX);
bb.SetUInt8(HDLCInfo.WindowSizeRX);
bb.SetUInt8(GXCommon.GetSize(Limits.WindowSizeRX));
bb.Add(Limits.WindowSizeRX);
bb.SetUInt8(2, (byte)(bb.Size - 3));
return(GXDLMS.SplitToHdlcFrames(Settings, (byte)Command.Ua, bb));
}
