diff options
Diffstat (limited to 'lib/zstd/common/fse.h')
| -rw-r--r-- | lib/zstd/common/fse.h | 103 |
1 files changed, 9 insertions, 94 deletions
diff --git a/lib/zstd/common/fse.h b/lib/zstd/common/fse.h index 4507043b2287..b36ce7a2a8c3 100644 --- a/lib/zstd/common/fse.h +++ b/lib/zstd/common/fse.h @@ -1,7 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */ /* ****************************************************************** * FSE : Finite State Entropy codec * Public Prototypes declaration - * Copyright (c) Yann Collet, Facebook, Inc. + * Copyright (c) Meta Platforms, Inc. and affiliates. * * You can contact the author at : * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy @@ -11,8 +12,6 @@ * in the COPYING file in the root directory of this source tree). * You may select, at your option, one of the above-listed licenses. ****************************************************************** */ - - #ifndef FSE_H #define FSE_H @@ -22,7 +21,6 @@ ******************************************/ #include "zstd_deps.h" /* size_t, ptrdiff_t */ - /*-***************************************** * FSE_PUBLIC_API : control library symbols visibility ******************************************/ @@ -50,34 +48,6 @@ FSE_PUBLIC_API unsigned FSE_versionNumber(void); /*< library version number; to be used when checking dll version */ -/*-**************************************** -* FSE simple functions -******************************************/ -/*! FSE_compress() : - Compress content of buffer 'src', of size 'srcSize', into destination buffer 'dst'. - 'dst' buffer must be already allocated. Compression runs faster is dstCapacity >= FSE_compressBound(srcSize). - @return : size of compressed data (<= dstCapacity). - Special values : if return == 0, srcData is not compressible => Nothing is stored within dst !!! - if return == 1, srcData is a single byte symbol * srcSize times. Use RLE compression instead. - if FSE_isError(return), compression failed (more details using FSE_getErrorName()) -*/ -FSE_PUBLIC_API size_t FSE_compress(void* dst, size_t dstCapacity, - const void* src, size_t srcSize); - -/*! FSE_decompress(): - Decompress FSE data from buffer 'cSrc', of size 'cSrcSize', - into already allocated destination buffer 'dst', of size 'dstCapacity'. - @return : size of regenerated data (<= maxDstSize), - or an error code, which can be tested using FSE_isError() . - - ** Important ** : FSE_decompress() does not decompress non-compressible nor RLE data !!! - Why ? : making this distinction requires a header. - Header management is intentionally delegated to the user layer, which can better manage special cases. -*/ -FSE_PUBLIC_API size_t FSE_decompress(void* dst, size_t dstCapacity, - const void* cSrc, size_t cSrcSize); - - /*-***************************************** * Tool functions ******************************************/ @@ -89,20 +59,6 @@ FSE_PUBLIC_API const char* FSE_getErrorName(size_t code); /* provides error co /*-***************************************** -* FSE advanced functions -******************************************/ -/*! FSE_compress2() : - Same as FSE_compress(), but allows the selection of 'maxSymbolValue' and 'tableLog' - Both parameters can be defined as '0' to mean : use default value - @return : size of compressed data - Special values : if return == 0, srcData is not compressible => Nothing is stored within cSrc !!! - if return == 1, srcData is a single byte symbol * srcSize times. Use RLE compression. - if FSE_isError(return), it's an error code. -*/ -FSE_PUBLIC_API size_t FSE_compress2 (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog); - - -/*-***************************************** * FSE detailed API ******************************************/ /*! @@ -161,8 +117,6 @@ FSE_PUBLIC_API size_t FSE_writeNCount (void* buffer, size_t bufferSize, /*! Constructor and Destructor of FSE_CTable. Note that FSE_CTable size depends on 'tableLog' and 'maxSymbolValue' */ typedef unsigned FSE_CTable; /* don't allocate that. It's only meant to be more restrictive than void* */ -FSE_PUBLIC_API FSE_CTable* FSE_createCTable (unsigned maxSymbolValue, unsigned tableLog); -FSE_PUBLIC_API void FSE_freeCTable (FSE_CTable* ct); /*! FSE_buildCTable(): Builds `ct`, which must be already allocated, using FSE_createCTable(). @@ -238,23 +192,7 @@ FSE_PUBLIC_API size_t FSE_readNCount_bmi2(short* normalizedCounter, unsigned* maxSymbolValuePtr, unsigned* tableLogPtr, const void* rBuffer, size_t rBuffSize, int bmi2); -/*! Constructor and Destructor of FSE_DTable. - Note that its size depends on 'tableLog' */ typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */ -FSE_PUBLIC_API FSE_DTable* FSE_createDTable(unsigned tableLog); -FSE_PUBLIC_API void FSE_freeDTable(FSE_DTable* dt); - -/*! FSE_buildDTable(): - Builds 'dt', which must be already allocated, using FSE_createDTable(). - return : 0, or an errorCode, which can be tested using FSE_isError() */ -FSE_PUBLIC_API size_t FSE_buildDTable (FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog); - -/*! FSE_decompress_usingDTable(): - Decompress compressed source `cSrc` of size `cSrcSize` using `dt` - into `dst` which must be already allocated. - @return : size of regenerated data (necessarily <= `dstCapacity`), - or an errorCode, which can be tested using FSE_isError() */ -FSE_PUBLIC_API size_t FSE_decompress_usingDTable(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, const FSE_DTable* dt); /*! Tutorial : @@ -286,13 +224,11 @@ If there is an error, the function will return an error code, which can be teste #endif /* FSE_H */ + #if !defined(FSE_H_FSE_STATIC_LINKING_ONLY) #define FSE_H_FSE_STATIC_LINKING_ONLY - -/* *** Dependency *** */ #include "bitstream.h" - /* ***************************************** * Static allocation *******************************************/ @@ -317,16 +253,6 @@ If there is an error, the function will return an error code, which can be teste unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus); /*< same as FSE_optimalTableLog(), which used `minus==2` */ -/* FSE_compress_wksp() : - * Same as FSE_compress2(), but using an externally allocated scratch buffer (`workSpace`). - * FSE_COMPRESS_WKSP_SIZE_U32() provides the minimum size required for `workSpace` as a table of FSE_CTable. - */ -#define FSE_COMPRESS_WKSP_SIZE_U32(maxTableLog, maxSymbolValue) ( FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue) + ((maxTableLog > 12) ? (1 << (maxTableLog - 2)) : 1024) ) -size_t FSE_compress_wksp (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize); - -size_t FSE_buildCTable_raw (FSE_CTable* ct, unsigned nbBits); -/*< build a fake FSE_CTable, designed for a flat distribution, where each symbol uses nbBits */ - size_t FSE_buildCTable_rle (FSE_CTable* ct, unsigned char symbolValue); /*< build a fake FSE_CTable, designed to compress always the same symbolValue */ @@ -344,19 +270,11 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct, const short* normalizedCounter, unsi FSE_PUBLIC_API size_t FSE_buildDTable_wksp(FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize); /*< Same as FSE_buildDTable(), using an externally allocated `workspace` produced with `FSE_BUILD_DTABLE_WKSP_SIZE_U32(maxSymbolValue)` */ -size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits); -/*< build a fake FSE_DTable, designed to read a flat distribution where each symbol uses nbBits */ - -size_t FSE_buildDTable_rle (FSE_DTable* dt, unsigned char symbolValue); -/*< build a fake FSE_DTable, designed to always generate the same symbolValue */ - -#define FSE_DECOMPRESS_WKSP_SIZE_U32(maxTableLog, maxSymbolValue) (FSE_DTABLE_SIZE_U32(maxTableLog) + FSE_BUILD_DTABLE_WKSP_SIZE_U32(maxTableLog, maxSymbolValue) + (FSE_MAX_SYMBOL_VALUE + 1) / 2 + 1) +#define FSE_DECOMPRESS_WKSP_SIZE_U32(maxTableLog, maxSymbolValue) (FSE_DTABLE_SIZE_U32(maxTableLog) + 1 + FSE_BUILD_DTABLE_WKSP_SIZE_U32(maxTableLog, maxSymbolValue) + (FSE_MAX_SYMBOL_VALUE + 1) / 2 + 1) #define FSE_DECOMPRESS_WKSP_SIZE(maxTableLog, maxSymbolValue) (FSE_DECOMPRESS_WKSP_SIZE_U32(maxTableLog, maxSymbolValue) * sizeof(unsigned)) -size_t FSE_decompress_wksp(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, unsigned maxLog, void* workSpace, size_t wkspSize); -/*< same as FSE_decompress(), using an externally allocated `workSpace` produced with `FSE_DECOMPRESS_WKSP_SIZE_U32(maxLog, maxSymbolValue)` */ - size_t FSE_decompress_wksp_bmi2(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, unsigned maxLog, void* workSpace, size_t wkspSize, int bmi2); -/*< Same as FSE_decompress_wksp() but with dynamic BMI2 support. Pass 1 if your CPU supports BMI2 or 0 if it doesn't. */ +/*< same as FSE_decompress(), using an externally allocated `workSpace` produced with `FSE_DECOMPRESS_WKSP_SIZE_U32(maxLog, maxSymbolValue)`. + * Set bmi2 to 1 if your CPU supports BMI2 or 0 if it doesn't */ typedef enum { FSE_repeat_none, /*< Cannot use the previous table */ @@ -539,20 +457,20 @@ MEM_STATIC void FSE_encodeSymbol(BIT_CStream_t* bitC, FSE_CState_t* statePtr, un FSE_symbolCompressionTransform const symbolTT = ((const FSE_symbolCompressionTransform*)(statePtr->symbolTT))[symbol]; const U16* const stateTable = (const U16*)(statePtr->stateTable); U32 const nbBitsOut = (U32)((statePtr->value + symbolTT.deltaNbBits) >> 16); - BIT_addBits(bitC, statePtr->value, nbBitsOut); + BIT_addBits(bitC, (BitContainerType)statePtr->value, nbBitsOut); statePtr->value = stateTable[ (statePtr->value >> nbBitsOut) + symbolTT.deltaFindState]; } MEM_STATIC void FSE_flushCState(BIT_CStream_t* bitC, const FSE_CState_t* statePtr) { - BIT_addBits(bitC, statePtr->value, statePtr->stateLog); + BIT_addBits(bitC, (BitContainerType)statePtr->value, statePtr->stateLog); BIT_flushBits(bitC); } /* FSE_getMaxNbBits() : * Approximate maximum cost of a symbol, in bits. - * Fractional get rounded up (i.e : a symbol with a normalized frequency of 3 gives the same result as a frequency of 2) + * Fractional get rounded up (i.e. a symbol with a normalized frequency of 3 gives the same result as a frequency of 2) * note 1 : assume symbolValue is valid (<= maxSymbolValue) * note 2 : if freq[symbolValue]==0, @return a fake cost of tableLog+1 bits */ MEM_STATIC U32 FSE_getMaxNbBits(const void* symbolTTPtr, U32 symbolValue) @@ -705,7 +623,4 @@ MEM_STATIC unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr) #define FSE_TABLESTEP(tableSize) (((tableSize)>>1) + ((tableSize)>>3) + 3) - #endif /* FSE_STATIC_LINKING_ONLY */ - - |