diff options
Diffstat (limited to 'src/lib/lzmadecode.c')
| -rw-r--r-- | src/lib/lzmadecode.c | 97 |
1 files changed, 70 insertions, 27 deletions
diff --git a/src/lib/lzmadecode.c b/src/lib/lzmadecode.c index d2769d9e8f..e74116040a 100644 --- a/src/lib/lzmadecode.c +++ b/src/lib/lzmadecode.c @@ -33,9 +33,12 @@ * to byte reads for last 4 bytes since RC_TEST returns an error when BufferLim * is *reached* (not surpassed!), meaning we can't allow that to happen while * there are still bytes to decode from the algorithm's point of view. */ -#define RC_READ_BYTE (look_ahead_ptr < 4 ? look_ahead.raw[look_ahead_ptr++] \ - : ((((uintptr_t) Buffer & 3) || ((SizeT) (BufferLim - Buffer) <= 4)) ? (*Buffer++) \ - : ((look_ahead.dw = *(UInt32 *)Buffer), (Buffer += 4), (look_ahead_ptr = 1), look_ahead.raw[0]))) +#define RC_READ_BYTE \ + (look_ahead_ptr < 4 ? look_ahead.raw[look_ahead_ptr++] \ + : ((((uintptr_t) Buffer & 3) \ + || ((SizeT) (BufferLim - Buffer) <= 4)) ? (*Buffer++) \ + : ((look_ahead.dw = *(UInt32 *)Buffer), (Buffer += 4), \ + (look_ahead_ptr = 1), look_ahead.raw[0]))) #define RC_INIT2 Code = 0; Range = 0xFFFFFFFF; \ { \ @@ -50,18 +53,41 @@ #define RC_TEST { if (Buffer == BufferLim) return LZMA_RESULT_DATA_ERROR; } -#define RC_INIT(buffer, bufferSize) Buffer = buffer; BufferLim = buffer + bufferSize; RC_INIT2 +#define RC_INIT(buffer, bufferSize) Buffer = buffer; \ + BufferLim = buffer + bufferSize; RC_INIT2 -#define RC_NORMALIZE if (Range < kTopValue) { RC_TEST; Range <<= 8; Code = (Code << 8) | RC_READ_BYTE; } - -#define IfBit0(p) RC_NORMALIZE; bound = (Range >> kNumBitModelTotalBits) * *(p); if (Code < bound) -#define UpdateBit0(p) Range = bound; *(p) += (kBitModelTotal - *(p)) >> kNumMoveBits; -#define UpdateBit1(p) Range -= bound; Code -= bound; *(p) -= (*(p)) >> kNumMoveBits; +#define RC_NORMALIZE \ + if (Range < kTopValue) { \ + RC_TEST; \ + Range <<= 8; \ + Code = (Code << 8) | RC_READ_BYTE; \ + } -#define RC_GET_BIT2(p, mi, A0, A1) IfBit0(p) \ - { UpdateBit0(p); mi <<= 1; A0; } else \ - { UpdateBit1(p); mi = (mi + mi) + 1; A1; } +#define IfBit0(p) \ + RC_NORMALIZE; \ + bound = (Range >> kNumBitModelTotalBits) * *(p); \ + if (Code < bound) + +#define UpdateBit0(p) \ + Range = bound; \ + *(p) += (kBitModelTotal - *(p)) >> kNumMoveBits; + +#define UpdateBit1(p) \ + Range -= bound; \ + Code -= bound; \ + *(p) -= (*(p)) >> kNumMoveBits; + +#define RC_GET_BIT2(p, mi, A0, A1) \ + IfBit0(p) { \ + UpdateBit0(p); \ + mi <<= 1; \ + A0; \ + } else { \ + UpdateBit1(p); \ + mi = (mi + mi) + 1; \ + A1; \ + } #define RC_GET_BIT(p, mi) RC_GET_BIT2(p, mi, ;, ;) @@ -128,7 +154,8 @@ StopCompilingDueBUG #endif -int LzmaDecodeProperties(CLzmaProperties *propsRes, const unsigned char *propsData, int size) +int LzmaDecodeProperties(CLzmaProperties *propsRes, + const unsigned char *propsData, int size) { unsigned char prop0; if (size < LZMA_PROPERTIES_SIZE) @@ -252,16 +279,21 @@ int LzmaDecode(CLzmaDecoderState *vs, prob = p + IsRepG0 + state; IfBit0(prob) { UpdateBit0(prob); - prob = p + IsRep0Long + (state << kNumPosBitsMax) + posState; + prob = p + IsRep0Long + + (state << kNumPosBitsMax) + + posState; IfBit0(prob) { UpdateBit0(prob); if (nowPos == 0) return LZMA_RESULT_DATA_ERROR; - state = state < kNumLitStates ? 9 : 11; - previousByte = outStream[nowPos - rep0]; - outStream[nowPos++] = previousByte; + state = state < kNumLitStates + ? 9 : 11; + previousByte = outStream[nowPos + - rep0]; + outStream[nowPos++] = + previousByte; continue; } else @@ -297,7 +329,8 @@ int LzmaDecode(CLzmaDecoderState *vs, CProb *probLen = prob + LenChoice; IfBit0(probLen) { UpdateBit0(probLen); - probLen = prob + LenLow + (posState << kLenNumLowBits); + probLen = prob + LenLow + + (posState << kLenNumLowBits); offset = 0; numBits = kLenNumLowBits; } else { @@ -305,17 +338,21 @@ int LzmaDecode(CLzmaDecoderState *vs, probLen = prob + LenChoice2; IfBit0(probLen) { UpdateBit0(probLen); - probLen = prob + LenMid + (posState << kLenNumMidBits); + probLen = prob + LenMid + + (posState << + kLenNumMidBits); offset = kLenNumLowSymbols; numBits = kLenNumMidBits; } else { UpdateBit1(probLen); probLen = prob + LenHigh; - offset = kLenNumLowSymbols + kLenNumMidSymbols; + offset = kLenNumLowSymbols + + kLenNumMidSymbols; numBits = kLenNumHighBits; } } - RangeDecoderBitTreeDecode(probLen, numBits, len); + RangeDecoderBitTreeDecode(probLen, numBits, + len); len += offset; } @@ -323,15 +360,19 @@ int LzmaDecode(CLzmaDecoderState *vs, int posSlot; state += kNumLitStates; prob = p + PosSlot + - ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) << + ((len < kNumLenToPosStates ? len : + kNumLenToPosStates - 1) << kNumPosSlotBits); - RangeDecoderBitTreeDecode(prob, kNumPosSlotBits, posSlot); + RangeDecoderBitTreeDecode(prob, kNumPosSlotBits, + posSlot); if (posSlot >= kStartPosModelIndex) { - int numDirectBits = ((posSlot >> 1) - 1); + int numDirectBits = ((posSlot >> 1) + - 1); rep0 = (2 | ((UInt32)posSlot & 1)); if (posSlot < kEndPosModelIndex) { rep0 <<= numDirectBits; - prob = p + SpecPos + rep0 - posSlot - 1; + prob = p + SpecPos + rep0 + - posSlot - 1; } else { numDirectBits -= kNumAlignBits; do { @@ -351,8 +392,10 @@ int LzmaDecode(CLzmaDecoderState *vs, int i = 1; int mi = 1; do { - CProb *prob3 = prob + mi; - RC_GET_BIT2(prob3, mi, ;, rep0 |= i); + CProb *prob3 = prob + + mi; + RC_GET_BIT2(prob3, mi, + ;, rep0 |= i); i <<= 1; } while (--numDirectBits != 0); } |