public void Read(
ByteBuf byteBuf,
ref WebSocketReadState state,
out WebSocketFrameInfo?frameInfo,
out IWebSocketDecoderStep nextStep)
{
frameInfo = null;
nextStep = null;
int factPayloadLen = state.ExtendedPayloadLen > 0
? (int)state.ExtendedPayloadLen
: state.PayloadLen;
if (byteBuf.ReadableBytes() < factPayloadLen)
{
return;
}
byte[] mask = new byte[4];
state.MaskingKey.CopyTo(mask, 0);
frameInfo = new WebSocketFrameInfo(
Utils.GetFrameType(state.OpCode),
state.Fin,
state.Mask,
mask,
factPayloadLen
);
}
public void Read(
ByteBuf byteBuf,
ref WebSocketReadState state,
out WebSocketFrameInfo?frameInfo,
out IWebSocketDecoderStep nextStep)
{
frameInfo = null;
nextStep = null;
if (state.PayloadLen == 126)
{
if (byteBuf.ReadableBytes() < 2)
{
return;
}
state.ExtendedPayloadLen = byteBuf.ReadUShort();
}
else if (state.PayloadLen == 127)
{
throw new NotSupportedException();
}
nextStep = state.Mask
? _readMaskingKeyStep
: _readPayloadDataStep;
}
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 Init(
IWebSocketDecoderStep readExtendedLenStep,
IWebSocketDecoderStep readMaskingKeyStep,
IWebSocketDecoderStep readPayloadDataStep)
{
_readExtendedLenStep = readExtendedLenStep;
_readMaskingKeyStep = readMaskingKeyStep;
_readPayloadDataStep = readPayloadDataStep;
}
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, out WebSocketFrame frame)
{
IWebSocketDecoderStep nextStep;
do
{
_currentStep.Read(byteBuf, ref _state, out frame, out nextStep);
if (nextStep != null)
{
_currentStep.Clear();
_currentStep = nextStep;
}
}
// Прерываемся только если текущий шаг не может быть закончен (буфер закончился) или если есть фрейм.
while (nextStep != null && frame == null);
// Если есть фрейм, то нужно сбросить состояние, чтобы при следующем чтении начинать с исходного состояния.
if (frame != null)
{
Clear();
}
}
public void Read(
ByteBuf byteBuf,
ref WebSocketReadState state,
out WebSocketFrameInfo?frameInfo,
out IWebSocketDecoderStep nextStep)
{
frameInfo = 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;
}
public void Init(IWebSocketDecoderStep readPayloadDataStep)
{
_readPayloadDataStep = readPayloadDataStep;
}
public void Clear()
{
_currentStep.Clear();
_currentStep = _readHeaderStep;
_state.Clear();
}