edd9a07322
`CHECK_F` macro moved to `error_private.h` (shared between `fse_compress.c` and `fse_decompress.c`). `ZSTD_limitCopy()` moved to `zstd_internal.h` (shared between `zstd_compress.c` and `zstd_decompress.c`). Erroneous build artefact `zstd.h` removed from repo.
287 lines
9.8 KiB
C
287 lines
9.8 KiB
C
/* ******************************************************************
|
|
* FSE : Finite State Entropy decoder
|
|
* Copyright (c) 2013-2020, Yann Collet, Facebook, Inc.
|
|
*
|
|
* You can contact the author at :
|
|
* - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy
|
|
* - Public forum : https://groups.google.com/forum/#!forum/lz4c
|
|
*
|
|
* This source code is licensed under both the BSD-style license (found in the
|
|
* LICENSE file in the root directory of this source tree) and the GPLv2 (found
|
|
* in the COPYING file in the root directory of this source tree).
|
|
* You may select, at your option, one of the above-listed licenses.
|
|
****************************************************************** */
|
|
|
|
|
|
/* **************************************************************
|
|
* Includes
|
|
****************************************************************/
|
|
#include <stdlib.h> /* malloc, free, qsort */
|
|
#include <string.h> /* memcpy, memset */
|
|
#include "bitstream.h"
|
|
#include "compiler.h"
|
|
#define FSE_STATIC_LINKING_ONLY
|
|
#include "fse.h"
|
|
#include "error_private.h"
|
|
|
|
|
|
/* **************************************************************
|
|
* Error Management
|
|
****************************************************************/
|
|
#define FSE_isError ERR_isError
|
|
#define FSE_STATIC_ASSERT(c) DEBUG_STATIC_ASSERT(c) /* use only *after* variable declarations */
|
|
|
|
|
|
/* **************************************************************
|
|
* 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);
|
|
U32 const nextState = symbolNext[symbol]++;
|
|
tableDecode[u].nbBits = (BYTE) (tableLog - BIT_highbit32(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_TEMPLATE 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 */
|