public WebSocketDecoderStateMachine()
{
var readHeaderStep = new WebSocketReadHeaderStep();
var readExtendedLenStep = new WebSocketReadExtendedPayloadLengthStep();
var readMaskingKeyStep = new WebSocketReadMaskingKeyStep();
var readPayloadDataStep = new WebSocketReadPayloadDataStep();
readHeaderStep.Init(readExtendedLenStep, readMaskingKeyStep, readPayloadDataStep);
readExtendedLenStep.Init(readMaskingKeyStep, readPayloadDataStep);
readMaskingKeyStep.Init(readPayloadDataStep);
_readHeaderStep = readHeaderStep;
_readExtendedLenStep = readExtendedLenStep;
_readMaskingKeyStep = readMaskingKeyStep;
_readPayloadDataStep = readPayloadDataStep;
// TODO: пулинг byte[]
_state = new WebSocketReadState(
false /* fin */,
0 /* opcode */,
false /* mask */,
0 /* payloadLen */,
0 /* extendedPayloadLen */,
new byte[4] /* maskingKeys */
);
_currentStep = _readHeaderStep;
}
public void Read(
ByteBuf byteBuf,
ref WebSocketReadState state,
out WebSocketFrame frame,
out IWebSocketDecoderStep nextStep)
{
frame = null;
nextStep = null;
if (byteBuf.ReadableBytes() < 4)
{
return;
}
state.MaskingKey[0] = byteBuf.ReadByte();
state.MaskingKey[1] = byteBuf.ReadByte();
state.MaskingKey[2] = byteBuf.ReadByte();
state.MaskingKey[3] = byteBuf.ReadByte();
nextStep = _readPayloadDataStep;
}
public void Read(
ByteBuf byteBuf,
ref WebSocketReadState state,
out WebSocketFrame frame,
out IWebSocketDecoderStep nextStep)
{
frame = null;
nextStep = null;
throw new NotSupportedException();
if (state.PayloadLen == 126)
{
if (byteBuf.ReadableBytes() < 2)
{
return;
}
state.ExtendedPayloadLen = byteBuf.ReadUShort();
}
else if (state.PayloadLen == 127)
{
if (byteBuf.ReadableBytes() < 8)
{
return;
}
state.ExtendedPayloadLen = byteBuf.ReadULong();
}
if (state.Mask)
{
nextStep = _readMaskingKeyStep;
}
else
{
nextStep = _readPayloadDataStep;
}
}
public void Read(
ByteBuf byteBuf,
ref WebSocketReadState state,
out WebSocketFrame frame,
out IWebSocketDecoderStep nextStep)
{
frame = null;
nextStep = null;
if (byteBuf.ReadableBytes() < 2)
{
return;
}
state.Clear();
byte headerByte1 = byteBuf.ReadByte();
byte headerByte2 = byteBuf.ReadByte();
state.Fin = (headerByte1 & Utils.MaskFin) == Utils.MaskFin;
state.OpCode = (byte)(headerByte1 & Utils.MaskOpCode);
state.Mask = (headerByte2 & Utils.MaskMask) == Utils.MaskMask;
state.PayloadLen = (byte)(headerByte2 & Utils.MaskPayloadLen);
if (state.PayloadLen > 125)
{
nextStep = _readExtendedLenStep;
}
else if (state.Mask)
{
nextStep = _readMaskingKeyStep;
}
else
{
nextStep = _readPayloadDataStep;
}
}
public void Read(
ByteBuf byteBuf,
ref WebSocketReadState state,
out WebSocketFrame frame,
out IWebSocketDecoderStep nextStep)
{
frame = null;
nextStep = null;
if (byteBuf.ReadableBytes() < state.PayloadLen)
{
return;
}
// TODO: alloc ByteBuf
byte[] frameBytes = new byte[state.PayloadLen];
// TODO: оптимизация
for (int i = 0; i < state.PayloadLen; i++)
{
frameBytes[i] = byteBuf.ReadByte();
}
if (state.Mask)
{
for (int i = 0; i < frameBytes.Length; i++)
{
frameBytes[i] ^= state.MaskingKey[i % 4];
}
}
frame = new WebSocketFrame();
frame.IsFinal = state.Fin;
frame.Type = Utils.GetFrameType(state.OpCode);
frame.Bytes = frameBytes;
}
