IEnumerable <ByteBuffer> CopySequencer()
{
active = true;
var reader = source.Read(OnSourceData, OnSourceError, OnSourceClose);
target.PauseWriting();
yield return(new ByteBuffer(new byte[0], 0, 0));
while (active)
{
var buffer = currentBuffer;
target.PauseWriting();
source.ResumeReading();
yield return(buffer);
}
reader.Dispose();
if (ownsSource)
{
source.Close();
}
source = null;
target = null;
currentBuffer = null;
}
/// <summary>
/// Return a message or null if timeout passes without a complete message ending with Eof can be found
/// </summary>
/// <returns></returns>
public IncomingMessage TryReadNext()
{
// at start, some left overs might still be at the beginning of the buffer,
// currentIndex can therefore be greater than 0
while (_currentBufferIndex < MaxMsgSize)
{
//Copy all bytes that can be from stream
var byteCount = _byteStream.Read(_buffer, _currentBufferIndex, BufSize - _currentBufferIndex);
if (byteCount > 0)
{
Logger.Debug($"Found {byteCount} bytes in UART. Copied to channel buffer starting at {_currentBufferIndex}");
}
else
{
return(null);
}
_currentBufferIndex += byteCount;
//Looking for EOF in the last byteCount of the buffer starting at previous _currentBufferIndex
while (_eofMatchCharCount < Eof.Length && _eofSeekIndex < _currentBufferIndex)
{
if (_buffer[_eofSeekIndex] == Eof[_eofMatchCharCount])
{
_eofMatchCharCount++;
}
else
{
_eofMatchCharCount = 0;
}
_eofSeekIndex++;
}
if (_eofMatchCharCount == Eof.Length)
{
Logger.Debug("EOF Found... Will extract 0..EOF from channel Buffer (remaining bytes shifted left in channel buffer)");
_eofMatchCharCount = 0;
//Copy buffer to msgBytes
var msgBytes = new byte[_eofSeekIndex];
for (var i = 0; i < _eofSeekIndex; i++)
{
msgBytes[i] = _buffer[i];
}
//Remove msgbytes from buffer and shift bytes left
for (var i = 0; i < _currentBufferIndex - _eofSeekIndex; i++)
{
_buffer[i] = _buffer[_eofSeekIndex + i];
}
_currentBufferIndex = _currentBufferIndex - _eofSeekIndex;
_eofSeekIndex = 0;
Logger.Debug(() => $"Found message in channel buffer : {BitConverter.ToString(msgBytes)}");
var parser = _messageParserFactory.Build(msgBytes);
IncomingMessage msg = null;
try
{
msg = parser.Parse(msgBytes);
}
catch (ArgumentException e)
{
Logger.Error(e);
return(null);
}
Logger.Info(() => $"Incoming message parsed to {msg}");
return(msg);
}
if (byteCount > 0)
{
Logger.Debug("EOF not found.. yet");
}
}
if (_currentBufferIndex >= MaxMsgSize) //Drop first 64 bytes and shift left in buffer
{
for (int i = 0; i < BufSize - MaxMsgSize; i++)
{
_buffer[i] = _buffer[MaxMsgSize + i];
}
_currentBufferIndex = _eofSeekIndex = _eofMatchCharCount = 0;
}
return(null);
}
