QuietUnrar/libunrar/coder.cpp

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inline unsigned int RangeCoder::GetChar()
{
return(UnpackRead->GetChar());
}
void RangeCoder::InitDecoder(Unpack *UnpackRead)
{
RangeCoder::UnpackRead=UnpackRead;
low=code=0;
range=uint(-1);
for (int i=0;i < 4;i++)
code=(code << 8) | GetChar();
}
// (int) cast before "low" added only to suppress compiler warnings.
#define ARI_DEC_NORMALIZE(code,low,range,read) \
{ \
while ((low^(low+range))<TOP || range<BOT && ((range=-(int)low&(BOT-1)),1)) \
{ \
code=(code << 8) | read->GetChar(); \
range <<= 8; \
low <<= 8; \
} \
}
inline int RangeCoder::GetCurrentCount()
{
return (code-low)/(range /= SubRange.scale);
}
inline uint RangeCoder::GetCurrentShiftCount(uint SHIFT)
{
return (code-low)/(range >>= SHIFT);
}
inline void RangeCoder::Decode()
{
low += range*SubRange.LowCount;
range *= SubRange.HighCount-SubRange.LowCount;
}