public int Decode(byte[] bytes, int offset, int size)
{
DecoderHelper.ValidateSize(size);
try
{
int bytesConsumed;
switch (_currentState)
{
case State.ReadingEnvelopeChunkSize:
bytesConsumed = _sizeDecoder.Decode(bytes, offset, size);
if (_sizeDecoder.IsValueDecoded)
{
_chunkSize = _sizeDecoder.Value;
_sizeDecoder.Reset();
if (_chunkSize == 0)
{
_currentState = State.EnvelopeEnd;
}
else
{
_currentState = State.ChunkStart;
_chunkBytesNeeded = _chunkSize;
}
}
break;
case State.ChunkStart:
bytesConsumed = 0;
_currentState = State.ReadingEnvelopeBytes;
break;
case State.ReadingEnvelopeBytes:
bytesConsumed = size;
if (bytesConsumed > _chunkBytesNeeded)
{
bytesConsumed = _chunkBytesNeeded;
}
_chunkBytesNeeded -= bytesConsumed;
if (_chunkBytesNeeded == 0)
{
_currentState = State.ChunkEnd;
}
break;
case State.ChunkEnd:
bytesConsumed = 0;
_currentState = State.ReadingEnvelopeChunkSize;
break;
case State.EnvelopeEnd:
ValidateRecordType(FramingRecordType.End, (FramingRecordType)bytes[offset]);
bytesConsumed = 1;
_currentState = State.End;
break;
case State.End:
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
CreateException(new InvalidDataException(SR.FramingAtEnd)));
default:
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
CreateException(new InvalidDataException(SR.InvalidDecoderStateMachine)));
}
StreamPosition += bytesConsumed;
return(bytesConsumed);
}
catch (InvalidDataException e)
{
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(CreateException(e));
}
}
public void Reset()
{
_currentState = State.ReadingSize;
_sizeDecoder.Reset();
}
