private State YieldTagBit(OutputInfo oi)
{
if (CanTakeByte(oi))
{
if (_match.Length == 0)
{
AddTagBit(oi, HeatshrinkLiteralMarker);
return(State.HsesYieldLiteral);
}
AddTagBit(oi, HeatshrinkBackrefMarker);
_outgoingBits = _match.Pos - 1;
_outgoingBitsCount = _windowSize;
return(State.HsesYieldBrIndex);
}
return(State.HsesYieldTagBit); /* output is full, continue */
}
private State FlushBitBuffer(OutputInfo oi)
{
if (_bitIndex == 0x80)
{
return(State.HsesDone);
}
else if (CanTakeByte(oi))
{
oi.Buf[oi.OutputSize++] = (byte)_currentByte;
return(State.HsesDone);
}
else
{
return(State.HsesFlushBits);
}
}
private State YieldBackRefIndex(OutputInfo oi)
{
if (CanTakeByte(oi))
{
if (push_outgoing_bits(oi) > 0)
{
return(State.HsesYieldBrIndex); /* continue */
}
else
{
_outgoingBits = _match.Length - 1;
_outgoingBitsCount = _lookAhead;
return(State.HsesYieldBrLength); /* done */
}
}
else
{
return(State.HsesYieldBrIndex); /* continue */
}
}
private State YieldBackRefLength(OutputInfo oi)
{
if (CanTakeByte(oi))
{
if (push_outgoing_bits(oi) > 0)
{
return(State.HsesYieldBrLength);
}
else
{
_match.ScanIndex += _match.Length;
_match.Length = 0;
return(State.HsesSearch);
}
}
else
{
return(State.HsesYieldBrLength);
}
}
private int push_outgoing_bits(OutputInfo oi)
{
int count;
byte bits;
if (_outgoingBitsCount > 8)
{
count = 8;
bits = (byte)(_outgoingBits >> (_outgoingBitsCount - 8));
}
else
{
count = _outgoingBitsCount;
bits = (byte)_outgoingBits;
}
if (count > 0)
{
PushBits(count, bits, oi);
_outgoingBitsCount -= count;
}
return(count);
}
private void AddTagBit(OutputInfo oi, byte tag)
{
PushBits(1, tag, oi);
}
private bool CanTakeByte(OutputInfo oi)
{
return(oi.OutputSize < oi.BufSize);
}
/// <summary>
/// Poll for output from the encoder, copying at most OUT_BUF_SIZE bytes into
/// OUT_BUF (setting *OUTPUT_SIZE to the actual amount copied).
/// </summary>
/// <param name="outBuf"></param>
/// <returns></returns>
public Result Poll(byte[] outBuf /* size_t *output_size */)
{
if (outBuf == null)
{
throw new ArgumentException("outBuf must not be null");
}
var outBufSize = outBuf.Length;
if (outBufSize == 0)
{
throw new ArgumentException("outBuf length must not be null");
}
var oi = new OutputInfo {
Buf = outBuf,
BufSize = outBuf.Length,
OutputSize = 0
};
while (true)
{
var inState = _state;
switch (inState)
{
case State.HsesNotFull:
return(Result.res(oi.OutputSize, Code.Empty));
case State.HsesFilled:
DoIndexing();
_state = State.HsesSearch;
break;
case State.HsesSearch:
_state = StepSearch();
break;
case State.HsesYieldTagBit:
_state = YieldTagBit(oi);
break;
case State.HsesYieldLiteral:
_state = YieldLiteral(oi);
break;
case State.HsesYieldBrIndex:
_state = YieldBackRefIndex(oi);
break;
case State.HsesYieldBrLength:
_state = YieldBackRefLength(oi);
break;
case State.HsesSaveBacklog:
_state = SaveBacklog();
break;
case State.HsesFlushBits:
_state = FlushBitBuffer(oi);
return(Result.res(oi.OutputSize, Code.Empty));
case State.HsesDone:
return(Result.res(oi.OutputSize, Code.Empty));
default:
return(Result.res(oi.OutputSize, Code.ErrorMisuse));
}
if (_state == inState)
{
/* Check if output buffer is exhausted. */
if (oi.OutputSize == outBufSize)
{
return(Result.res(oi.OutputSize, Code.More));
}
}
}
// return new PollRes(output_size, PollRes.Res.EMPTY);
}
private void PushByte(OutputInfo oi, byte c)
{
//log.Debug(" -- pushing byte: 0x%02x ('%c')", c, isPrint(c) ? c : '.');
oi.Buf[oi.OutputSize++] = c;
}
/// <summary>
/// poll decoded bytes into outBuffer.
/// </summary>
/// <param name="outBuffer">must not be null</param>
/// <returns>count byte were polled</returns>
public Result Poll(byte[] outBuffer /*, int offset , size_t *output_size*/)
{
if (outBuffer == null)
{
throw new ArgumentException("outbuffer must not be null");
}
var outBufSize = outBuffer.Length;
var oi = new OutputInfo {
Buf = outBuffer,
BufSize = outBufSize,
OutputSize = 0
};
while (true)
{
var inState = _state;
switch (inState)
{
case State.HsdsTagBit:
_state = TagBit();
break;
case State.HsdsYieldLiteral:
_state = YieldLiteral(oi);
break;
case State.HsdsBackrefIndexMsb:
_state = BackrefIndexMsb();
break;
case State.HsdsBackrefIndexLsb:
_state = BackrefIndexLsb();
break;
case State.HsdsBackrefCountMsb:
_state = BackrefCountMsb();
break;
case State.HsdsBackrefCountLsb:
_state = BackrefCountLsb();
break;
case State.HsdsYieldBackref:
_state = YieldBackref(oi);
break;
default:
return(Result.res(Code.ErrorUnknown));
}
/* If the current state cannot advance, check if input or output
* buffer are exhausted. */
if (_state == inState)
{
if (oi.OutputSize == outBufSize)
{
return(Result.res(oi.OutputSize, Code.More));
}
return(Result.res(oi.OutputSize, Code.Empty));
}
}
}
