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Diffstat (limited to 'thirdparty/zstd/common/fse_decompress.c')
| -rw-r--r-- | thirdparty/zstd/common/fse_decompress.c | 328 |
1 files changed, 328 insertions, 0 deletions
diff --git a/thirdparty/zstd/common/fse_decompress.c b/thirdparty/zstd/common/fse_decompress.c new file mode 100644 index 0000000000..8474a4c079 --- /dev/null +++ b/thirdparty/zstd/common/fse_decompress.c @@ -0,0 +1,328 @@ +/* ****************************************************************** + FSE : Finite State Entropy decoder + Copyright (C) 2013-2015, Yann Collet. + + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following disclaimer + in the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + You can contact the author at : + - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy + - Public forum : https://groups.google.com/forum/#!forum/lz4c +****************************************************************** */ + + +/* ************************************************************** +* Compiler specifics +****************************************************************/ +#ifdef _MSC_VER /* Visual Studio */ +# define FORCE_INLINE static __forceinline +# include <intrin.h> /* For Visual 2005 */ +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +# pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */ +#else +# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ +# ifdef __GNUC__ +# define FORCE_INLINE static inline __attribute__((always_inline)) +# else +# define FORCE_INLINE static inline +# endif +# else +# define FORCE_INLINE static +# endif /* __STDC_VERSION__ */ +#endif + + +/* ************************************************************** +* Includes +****************************************************************/ +#include <stdlib.h> /* malloc, free, qsort */ +#include <string.h> /* memcpy, memset */ +#include "bitstream.h" +#define FSE_STATIC_LINKING_ONLY +#include "fse.h" + + +/* ************************************************************** +* Error Management +****************************************************************/ +#define FSE_isError ERR_isError +#define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */ + +/* check and forward error code */ +#define CHECK_F(f) { size_t const e = f; if (FSE_isError(e)) return e; } + + +/* ************************************************************** +* Templates +****************************************************************/ +/* + designed to be included + for type-specific functions (template emulation in C) + Objective is to write these functions only once, for improved maintenance +*/ + +/* safety checks */ +#ifndef FSE_FUNCTION_EXTENSION +# error "FSE_FUNCTION_EXTENSION must be defined" +#endif +#ifndef FSE_FUNCTION_TYPE +# error "FSE_FUNCTION_TYPE must be defined" +#endif + +/* Function names */ +#define FSE_CAT(X,Y) X##Y +#define FSE_FUNCTION_NAME(X,Y) FSE_CAT(X,Y) +#define FSE_TYPE_NAME(X,Y) FSE_CAT(X,Y) + + +/* Function templates */ +FSE_DTable* FSE_createDTable (unsigned tableLog) +{ + if (tableLog > FSE_TABLELOG_ABSOLUTE_MAX) tableLog = FSE_TABLELOG_ABSOLUTE_MAX; + return (FSE_DTable*)malloc( FSE_DTABLE_SIZE_U32(tableLog) * sizeof (U32) ); +} + +void FSE_freeDTable (FSE_DTable* dt) +{ + free(dt); +} + +size_t FSE_buildDTable(FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog) +{ + void* const tdPtr = dt+1; /* because *dt is unsigned, 32-bits aligned on 32-bits */ + FSE_DECODE_TYPE* const tableDecode = (FSE_DECODE_TYPE*) (tdPtr); + U16 symbolNext[FSE_MAX_SYMBOL_VALUE+1]; + + U32 const maxSV1 = maxSymbolValue + 1; + U32 const tableSize = 1 << tableLog; + U32 highThreshold = tableSize-1; + + /* Sanity Checks */ + if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return ERROR(maxSymbolValue_tooLarge); + if (tableLog > FSE_MAX_TABLELOG) return ERROR(tableLog_tooLarge); + + /* Init, lay down lowprob symbols */ + { FSE_DTableHeader DTableH; + DTableH.tableLog = (U16)tableLog; + DTableH.fastMode = 1; + { S16 const largeLimit= (S16)(1 << (tableLog-1)); + U32 s; + for (s=0; s<maxSV1; s++) { + if (normalizedCounter[s]==-1) { + tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s; + symbolNext[s] = 1; + } else { + if (normalizedCounter[s] >= largeLimit) DTableH.fastMode=0; + symbolNext[s] = normalizedCounter[s]; + } } } + memcpy(dt, &DTableH, sizeof(DTableH)); + } + + /* Spread symbols */ + { U32 const tableMask = tableSize-1; + U32 const step = FSE_TABLESTEP(tableSize); + U32 s, position = 0; + for (s=0; s<maxSV1; s++) { + int i; + for (i=0; i<normalizedCounter[s]; i++) { + tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s; + position = (position + step) & tableMask; + while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */ + } } + if (position!=0) return ERROR(GENERIC); /* position must reach all cells once, otherwise normalizedCounter is incorrect */ + } + + /* Build Decoding table */ + { U32 u; + for (u=0; u<tableSize; u++) { + FSE_FUNCTION_TYPE const symbol = (FSE_FUNCTION_TYPE)(tableDecode[u].symbol); + U16 nextState = symbolNext[symbol]++; + tableDecode[u].nbBits = (BYTE) (tableLog - BIT_highbit32 ((U32)nextState) ); + tableDecode[u].newState = (U16) ( (nextState << tableDecode[u].nbBits) - tableSize); + } } + + return 0; +} + + +#ifndef FSE_COMMONDEFS_ONLY + +/*-******************************************************* +* Decompression (Byte symbols) +*********************************************************/ +size_t FSE_buildDTable_rle (FSE_DTable* dt, BYTE symbolValue) +{ + void* ptr = dt; + FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; + void* dPtr = dt + 1; + FSE_decode_t* const cell = (FSE_decode_t*)dPtr; + + DTableH->tableLog = 0; + DTableH->fastMode = 0; + + cell->newState = 0; + cell->symbol = symbolValue; + cell->nbBits = 0; + + return 0; +} + + +size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits) +{ + void* ptr = dt; + FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; + void* dPtr = dt + 1; + FSE_decode_t* const dinfo = (FSE_decode_t*)dPtr; + const unsigned tableSize = 1 << nbBits; + const unsigned tableMask = tableSize - 1; + const unsigned maxSV1 = tableMask+1; + unsigned s; + + /* Sanity checks */ + if (nbBits < 1) return ERROR(GENERIC); /* min size */ + + /* Build Decoding Table */ + DTableH->tableLog = (U16)nbBits; + DTableH->fastMode = 1; + for (s=0; s<maxSV1; s++) { + dinfo[s].newState = 0; + dinfo[s].symbol = (BYTE)s; + dinfo[s].nbBits = (BYTE)nbBits; + } + + return 0; +} + +FORCE_INLINE size_t FSE_decompress_usingDTable_generic( + void* dst, size_t maxDstSize, + const void* cSrc, size_t cSrcSize, + const FSE_DTable* dt, const unsigned fast) +{ + BYTE* const ostart = (BYTE*) dst; + BYTE* op = ostart; + BYTE* const omax = op + maxDstSize; + BYTE* const olimit = omax-3; + + BIT_DStream_t bitD; + FSE_DState_t state1; + FSE_DState_t state2; + + /* Init */ + CHECK_F(BIT_initDStream(&bitD, cSrc, cSrcSize)); + + FSE_initDState(&state1, &bitD, dt); + FSE_initDState(&state2, &bitD, dt); + +#define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD) + + /* 4 symbols per loop */ + for ( ; (BIT_reloadDStream(&bitD)==BIT_DStream_unfinished) & (op<olimit) ; op+=4) { + op[0] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ + BIT_reloadDStream(&bitD); + + op[1] = FSE_GETSYMBOL(&state2); + + if (FSE_MAX_TABLELOG*4+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ + { if (BIT_reloadDStream(&bitD) > BIT_DStream_unfinished) { op+=2; break; } } + + op[2] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ + BIT_reloadDStream(&bitD); + + op[3] = FSE_GETSYMBOL(&state2); + } + + /* tail */ + /* note : BIT_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly BIT_DStream_completed */ + while (1) { + if (op>(omax-2)) return ERROR(dstSize_tooSmall); + *op++ = FSE_GETSYMBOL(&state1); + if (BIT_reloadDStream(&bitD)==BIT_DStream_overflow) { + *op++ = FSE_GETSYMBOL(&state2); + break; + } + + if (op>(omax-2)) return ERROR(dstSize_tooSmall); + *op++ = FSE_GETSYMBOL(&state2); + if (BIT_reloadDStream(&bitD)==BIT_DStream_overflow) { + *op++ = FSE_GETSYMBOL(&state1); + break; + } } + + return op-ostart; +} + + +size_t FSE_decompress_usingDTable(void* dst, size_t originalSize, + const void* cSrc, size_t cSrcSize, + const FSE_DTable* dt) +{ + const void* ptr = dt; + const FSE_DTableHeader* DTableH = (const FSE_DTableHeader*)ptr; + const U32 fastMode = DTableH->fastMode; + + /* select fast mode (static) */ + if (fastMode) return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1); + return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0); +} + + +size_t FSE_decompress_wksp(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, FSE_DTable* workSpace, unsigned maxLog) +{ + const BYTE* const istart = (const BYTE*)cSrc; + const BYTE* ip = istart; + short counting[FSE_MAX_SYMBOL_VALUE+1]; + unsigned tableLog; + unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE; + + /* normal FSE decoding mode */ + size_t const NCountLength = FSE_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize); + if (FSE_isError(NCountLength)) return NCountLength; + //if (NCountLength >= cSrcSize) return ERROR(srcSize_wrong); /* too small input size; supposed to be already checked in NCountLength, only remaining case : NCountLength==cSrcSize */ + if (tableLog > maxLog) return ERROR(tableLog_tooLarge); + ip += NCountLength; + cSrcSize -= NCountLength; + + CHECK_F( FSE_buildDTable (workSpace, counting, maxSymbolValue, tableLog) ); + + return FSE_decompress_usingDTable (dst, dstCapacity, ip, cSrcSize, workSpace); /* always return, even if it is an error code */ +} + + +typedef FSE_DTable DTable_max_t[FSE_DTABLE_SIZE_U32(FSE_MAX_TABLELOG)]; + +size_t FSE_decompress(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize) +{ + DTable_max_t dt; /* Static analyzer seems unable to understand this table will be properly initialized later */ + return FSE_decompress_wksp(dst, dstCapacity, cSrc, cSrcSize, dt, FSE_MAX_TABLELOG); +} + + + +#endif /* FSE_COMMONDEFS_ONLY */ |