public void ReceiveDataSet(ICommand command, byte presentationContextID, Action <Stream> dataSetReader)
{
if ((_pendingCommand == null) || (_pendingPresentationContext == 0))
{
throw new InvalidOperationException("No pending data set");
}
if (command != _pendingCommand)
{
throw new ArgumentException($"{command} does not match pending command {_pendingCommand}");
}
if (presentationContextID != _pendingPresentationContext)
{
throw new ArgumentException($"{presentationContextID} does not match pending presentation context {_pendingPresentationContext}");
}
if (Input.Position == EndOfDataTransferPDUPosition)
{
ReadNextDataTransferPDU();
}
using (var stream = new PresentationContextInputStream(this, FragmentType.DataSet))
{
if (stream.PresentationContextID != presentationContextID)
{
throw new IOException($"Expected PCID {presentationContextID} but got {stream.PresentationContextID}");
}
dataSetReader.Invoke(stream);
stream.SkipToEnd();
}
_pendingCommand = null;
_pendingPresentationContext = 0;
}
private ICommand ReadCommandFrom(PresentationContextInputStream stream)
{
var input = new BufferedStreamReader(stream);
var command = CommandSerialization.ReadFrom(input);
if (command is IMayHaveDataSet mayHaveDataSet)
{
if (command.IsFollowedByDataSet())
{
_pendingCommand = command;
_pendingPresentationContext = stream.PresentationContextID;
}
else if (mayHaveDataSet.IsDataSetRequired())
{
throw new IOException($"{command} must be followed by a data set");
}
}
else if (command.IsFollowedByDataSet())
{
throw new IOException($"Unexpected data set received for command {command}");
}
stream.SkipToEnd();
if (TraceWriter != null)
{
NetUtils.TraceOutput(TraceWriter, $"PC {stream.PresentationContextID} received ", command);
}
return(command);
}
public ICommand ReceiveCommand(byte presentationContextID)
{
EnsureNoPendingDataSet();
ReadNextPDU(DataUnitType.DataTransferPDU);
using (var stream = new PresentationContextInputStream(this, FragmentType.Command))
{
if (stream.PresentationContextID != presentationContextID)
{
throw new IOException($"Expected PCID {presentationContextID} but got {stream.PresentationContextID}");
}
return(ReadCommandFrom(stream));
}
}
public bool TryReceiveCommand(out byte presentationContextID, out ICommand command)
{
EnsureNoPendingDataSet();
if (ReadNextPDU(DataUnitType.DataTransferPDU, DataUnitType.ReleaseRequestPDU) is DataTransferPDUHeader)
{
using (var stream = new PresentationContextInputStream(this, FragmentType.Command))
{
presentationContextID = stream.PresentationContextID;
command = ReadCommandFrom(stream);
}
return(true);
}
else
{
presentationContextID = 0;
command = null;
return(false);
}
}
