misc/libphysfs/lzma/CPP/7zip/Compress/RangeCoder/RangeCoderOpt.h
author nemo
Mon, 10 Apr 2017 12:06:43 -0400
changeset 12213 bb5522e88ab2
permissions -rw-r--r--
bulk copy of latest physfs to our misc/libphysfs since this seems to fix an off-by-1 error reliably hit in readln read of 1 byte probably introduced in the addition of the buffered read. Whether this is excessive or whether libphysfs should even be maintained by us is another matter. But at least we shouldn't crash

// Compress/RangeCoder/RangeCoderOpt.h

#ifndef __COMPRESS_RANGECODER_OPT_H
#define __COMPRESS_RANGECODER_OPT_H

#define RC_INIT_VAR \
  UInt32 range = rangeDecoder->Range; \
  UInt32 code = rangeDecoder->Code;        

#define RC_FLUSH_VAR \
  rangeDecoder->Range = range; \
  rangeDecoder->Code = code;

#define RC_NORMALIZE \
  if (range < NCompress::NRangeCoder::kTopValue) \
    { code = (code << 8) | rangeDecoder->Stream.ReadByte(); range <<= 8; }

#define RC_GETBIT2(numMoveBits, prob, mi, A0, A1) \
  { UInt32 bound = (range >> NCompress::NRangeCoder::kNumBitModelTotalBits) * prob; \
  if (code < bound) \
  { A0; range = bound; \
    prob += (NCompress::NRangeCoder::kBitModelTotal - prob) >> numMoveBits; \
    mi <<= 1; } \
  else \
  { A1; range -= bound; code -= bound; prob -= (prob) >> numMoveBits; \
    mi = (mi + mi) + 1; }} \
  RC_NORMALIZE

#define RC_GETBIT(numMoveBits, prob, mi) RC_GETBIT2(numMoveBits, prob, mi, ; , ;)

#endif