///<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, GXDLMSConnectionEventArgs connectionInfo)
{
if (buff == null || buff.Length == 0)
{
return(null);
}
if (!Initialized)
{
throw new Exception("Server not Initialized.");
}
try
{
receivedData.Set(buff);
bool first = Settings.ServerAddress == 0 && Settings.ClientAddress == 0;
GXDLMS.GetData(Settings, receivedData, info);
//If all data is not received yet.
if (!info.IsComplete)
{
return(null);
}
receivedData.Clear();
if (first)
{
// Check is data send to this server.
if (!IsTarget(Settings.ServerAddress,
Settings.ClientAddress))
{
info.Clear();
return(null);
}
}
//If client want next frame.
if ((info.MoreData & RequestTypes.Frame) == RequestTypes.Frame)
{
return(GXDLMS.GetHdlcFrame(Settings, Settings.ReceiverReady(), replyData));
}
//Update command if transaction and next frame is asked.
if (info.Command == Command.None)
{
if (transaction != null)
{
info.Command = transaction.command;
}
}
//Check inactivity time out.
if (hdlcSetup != null)
{
if (info.Command == Command.Snrm)
{
dataReceived = DateTime.Now;
}
else
{
int elapsed = (int)(DateTime.Now - dataReceived).TotalSeconds;
//If inactivity time out is elapsed.
if (elapsed >= hdlcSetup.InactivityTimeout)
{
Reset();
dataReceived = DateTime.MinValue;
return(null);
}
dataReceived = DateTime.Now;
}
}
byte[] reply = HandleCommand(info.Command, info.Data, connectionInfo);
info.Clear();
return(reply);
}
catch (Exception ex)
{
Debug.WriteLine(ex.ToString());
if (info.Command != Command.None)
{
return(ReportError(info.Command, ErrorCode.HardwareFault));
}
else
{
Reset();
if (Settings.Connected)
{
Settings.Connected = false;
Disconnected(connectionInfo);
}
return(null);
}
}
}
///<summary>
///Generates an acknowledgment message, with which the server is informed to send next packets.
///</summary>
///<param name="type">
/// Frame type.
/// </param>
///<returns>
///Acknowledgment message as byte array.
///</returns>
internal static byte[] ReceiverReady(GXDLMSSettings settings, RequestTypes type)
{
if (type == RequestTypes.None)
{
throw new ArgumentException("Invalid receiverReady RequestTypes parameter.");
}
// Get next frame.
if ((type & RequestTypes.Frame) != 0)
{
byte id = settings.ReceiverReady();
return GetHdlcFrame(settings, id, null);
}
Command cmd;
if (settings.UseLogicalNameReferencing)
{
if (settings.IsServer)
{
cmd = Command.GetResponse;
}
else
{
cmd = Command.GetRequest;
}
}
else
{
if (settings.IsServer)
{
cmd = Command.ReadResponse;
}
else
{
cmd = Command.ReadRequest;
}
}
// Get next block.
GXByteBuffer bb = new GXByteBuffer(6);
if (settings.UseLogicalNameReferencing)
{
bb.SetUInt32(settings.BlockIndex);
}
else
{
bb.SetUInt16((UInt16)settings.BlockIndex);
}
settings.IncreaseBlockIndex();
byte[][] reply;
if (settings.UseLogicalNameReferencing)
{
GXDLMSLNParameters p = new GXDLMSLNParameters(settings, cmd, (byte)GetCommandType.NextDataBlock, bb, null, 0xff);
reply = GXDLMS.GetLnMessages(p);
}
else
{
GXDLMSSNParameters p = new GXDLMSSNParameters(settings, cmd, 1, (byte)VariableAccessSpecification.BlockNumberAccess, bb, null);
reply = GXDLMS.GetSnMessages(p);
}
return reply[0];
}
