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godot/thirdparty/zstd/compress/zstd_compress.c

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/**
* Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
/*-*************************************
* Tuning parameters
***************************************/
#ifndef ZSTD_CLEVEL_DEFAULT
# define ZSTD_CLEVEL_DEFAULT 3
#endif
/*-*************************************
* Dependencies
***************************************/
#include <string.h> /* memset */
#include "mem.h"
#define FSE_STATIC_LINKING_ONLY /* FSE_encodeSymbol */
#include "fse.h"
#define HUF_STATIC_LINKING_ONLY
#include "huf.h"
#include "zstd_internal.h" /* includes zstd.h */
#include "zstdmt_compress.h"
/*-*************************************
* Constants
***************************************/
static const U32 g_searchStrength = 8; /* control skip over incompressible data */
#define HASH_READ_SIZE 8
typedef enum { ZSTDcs_created=0, ZSTDcs_init, ZSTDcs_ongoing, ZSTDcs_ending } ZSTD_compressionStage_e;
/* entropy tables always have same size */
static size_t const hufCTable_size = HUF_CTABLE_SIZE(255);
static size_t const litlengthCTable_size = FSE_CTABLE_SIZE(LLFSELog, MaxLL);
static size_t const offcodeCTable_size = FSE_CTABLE_SIZE(OffFSELog, MaxOff);
static size_t const matchlengthCTable_size = FSE_CTABLE_SIZE(MLFSELog, MaxML);
static size_t const entropyScratchSpace_size = HUF_WORKSPACE_SIZE;
/*-*************************************
* Helper functions
***************************************/
size_t ZSTD_compressBound(size_t srcSize) {
size_t const lowLimit = 256 KB;
size_t const margin = (srcSize < lowLimit) ? (lowLimit-srcSize) >> 12 : 0; /* from 64 to 0 */
return srcSize + (srcSize >> 8) + margin;
}
/*-*************************************
* Sequence storage
***************************************/
static void ZSTD_resetSeqStore(seqStore_t* ssPtr)
{
ssPtr->lit = ssPtr->litStart;
ssPtr->sequences = ssPtr->sequencesStart;
ssPtr->longLengthID = 0;
}
/*-*************************************
* Context memory management
***************************************/
typedef enum { zcss_init=0, zcss_load, zcss_flush } ZSTD_cStreamStage;
struct ZSTD_CDict_s {
void* dictBuffer;
const void* dictContent;
size_t dictContentSize;
ZSTD_CCtx* refContext;
}; /* typedef'd to ZSTD_CDict within "zstd.h" */
struct ZSTD_CCtx_s {
const BYTE* nextSrc; /* next block here to continue on current prefix */
const BYTE* base; /* All regular indexes relative to this position */
const BYTE* dictBase; /* extDict indexes relative to this position */
U32 dictLimit; /* below that point, need extDict */
U32 lowLimit; /* below that point, no more data */
U32 nextToUpdate; /* index from which to continue dictionary update */
U32 nextToUpdate3; /* index from which to continue dictionary update */
U32 hashLog3; /* dispatch table : larger == faster, more memory */
U32 loadedDictEnd; /* index of end of dictionary */
U32 forceWindow; /* force back-references to respect limit of 1<<wLog, even for dictionary */
ZSTD_compressionStage_e stage;
U32 rep[ZSTD_REP_NUM];
U32 repToConfirm[ZSTD_REP_NUM];
U32 dictID;
int compressionLevel;
ZSTD_parameters requestedParams;
ZSTD_parameters appliedParams;
void* workSpace;
size_t workSpaceSize;
size_t blockSize;
U64 pledgedSrcSizePlusOne; /* this way, 0 (default) == unknown */
U64 consumedSrcSize;
XXH64_state_t xxhState;
ZSTD_customMem customMem;
size_t staticSize;
seqStore_t seqStore; /* sequences storage ptrs */
U32* hashTable;
U32* hashTable3;
U32* chainTable;
HUF_repeat hufCTable_repeatMode;
HUF_CElt* hufCTable;
U32 fseCTables_ready;
FSE_CTable* offcodeCTable;
FSE_CTable* matchlengthCTable;
FSE_CTable* litlengthCTable;
unsigned* entropyScratchSpace;
/* streaming */
char* inBuff;
size_t inBuffSize;
size_t inToCompress;
size_t inBuffPos;
size_t inBuffTarget;
char* outBuff;
size_t outBuffSize;
size_t outBuffContentSize;
size_t outBuffFlushedSize;
ZSTD_cStreamStage streamStage;
U32 frameEnded;
/* Dictionary */
ZSTD_dictMode_e dictMode; /* select restricting dictionary to "rawContent" or "fullDict" only */
U32 dictContentByRef;
ZSTD_CDict* cdictLocal;
const ZSTD_CDict* cdict;
const void* prefix;
size_t prefixSize;
/* Multi-threading */
U32 nbThreads;
ZSTDMT_CCtx* mtctx;
};
ZSTD_CCtx* ZSTD_createCCtx(void)
{
return ZSTD_createCCtx_advanced(ZSTD_defaultCMem);
}
ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem)
{
ZSTD_CCtx* cctx;
if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
cctx = (ZSTD_CCtx*) ZSTD_calloc(sizeof(ZSTD_CCtx), customMem);
if (!cctx) return NULL;
cctx->customMem = customMem;
cctx->compressionLevel = ZSTD_CLEVEL_DEFAULT;
ZSTD_STATIC_ASSERT(zcss_init==0);
ZSTD_STATIC_ASSERT(ZSTD_CONTENTSIZE_UNKNOWN==(0ULL - 1));
return cctx;
}
ZSTD_CCtx* ZSTD_initStaticCCtx(void *workspace, size_t workspaceSize)
{
ZSTD_CCtx* cctx = (ZSTD_CCtx*) workspace;
if (workspaceSize <= sizeof(ZSTD_CCtx)) return NULL; /* minimum size */
if ((size_t)workspace & 7) return NULL; /* must be 8-aligned */
memset(workspace, 0, workspaceSize); /* may be a bit generous, could memset be smaller ? */
cctx->staticSize = workspaceSize;
cctx->workSpace = (void*)(cctx+1);
cctx->workSpaceSize = workspaceSize - sizeof(ZSTD_CCtx);
/* entropy space (never moves) */
/* note : this code should be shared with resetCCtx, rather than copy/pasted */
{ void* ptr = cctx->workSpace;
cctx->hufCTable = (HUF_CElt*)ptr;
ptr = (char*)cctx->hufCTable + hufCTable_size;
cctx->offcodeCTable = (FSE_CTable*) ptr;
ptr = (char*)ptr + offcodeCTable_size;
cctx->matchlengthCTable = (FSE_CTable*) ptr;
ptr = (char*)ptr + matchlengthCTable_size;
cctx->litlengthCTable = (FSE_CTable*) ptr;
ptr = (char*)ptr + litlengthCTable_size;
assert(((size_t)ptr & 3) == 0); /* ensure correct alignment */
cctx->entropyScratchSpace = (unsigned*) ptr;
}
return cctx;
}
size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
{
if (cctx==NULL) return 0; /* support free on NULL */
if (cctx->staticSize) return ERROR(memory_allocation); /* not compatible with static CCtx */
ZSTD_free(cctx->workSpace, cctx->customMem);
cctx->workSpace = NULL;
ZSTD_freeCDict(cctx->cdictLocal);
cctx->cdictLocal = NULL;
ZSTDMT_freeCCtx(cctx->mtctx);
cctx->mtctx = NULL;
ZSTD_free(cctx, cctx->customMem);
return 0; /* reserved as a potential error code in the future */
}
size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx)
{
if (cctx==NULL) return 0; /* support sizeof on NULL */
DEBUGLOG(5, "sizeof(*cctx) : %u", (U32)sizeof(*cctx));
DEBUGLOG(5, "workSpaceSize : %u", (U32)cctx->workSpaceSize);
DEBUGLOG(5, "streaming buffers : %u", (U32)(cctx->outBuffSize + cctx->inBuffSize));
DEBUGLOG(5, "inner MTCTX : %u", (U32)ZSTDMT_sizeof_CCtx(cctx->mtctx));
return sizeof(*cctx) + cctx->workSpaceSize
+ ZSTD_sizeof_CDict(cctx->cdictLocal)
+ cctx->outBuffSize + cctx->inBuffSize
+ ZSTDMT_sizeof_CCtx(cctx->mtctx);
}
size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs)
{
return ZSTD_sizeof_CCtx(zcs); /* same object */
}
/* private API call, for dictBuilder only */
const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx) { return &(ctx->seqStore); }
static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx* cctx) { return cctx->appliedParams; }
/* older variant; will be deprecated */
size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned value)
{
switch(param)
{
case ZSTD_p_forceWindow : cctx->forceWindow = value>0; cctx->loadedDictEnd = 0; return 0;
ZSTD_STATIC_ASSERT(ZSTD_dm_auto==0);
ZSTD_STATIC_ASSERT(ZSTD_dm_rawContent==1);
case ZSTD_p_forceRawDict : cctx->dictMode = (ZSTD_dictMode_e)(value>0); return 0;
default: return ERROR(parameter_unknown);
}
}
#define ZSTD_CLEVEL_CUSTOM 999
static void ZSTD_cLevelToCParams(ZSTD_CCtx* cctx)
{
if (cctx->compressionLevel==ZSTD_CLEVEL_CUSTOM) return;
cctx->requestedParams.cParams = ZSTD_getCParams(cctx->compressionLevel,
cctx->pledgedSrcSizePlusOne-1, 0);
cctx->compressionLevel = ZSTD_CLEVEL_CUSTOM;
}
#define CLAMPCHECK(val,min,max) { \
if (((val)<(min)) | ((val)>(max))) { \
return ERROR(compressionParameter_outOfBound); \
} }
size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value)
{
if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
switch(param)
{
case ZSTD_p_compressionLevel :
if ((int)value > ZSTD_maxCLevel()) value = ZSTD_maxCLevel(); /* cap max compression level */
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
cctx->compressionLevel = value;
return 0;
case ZSTD_p_windowLog :
DEBUGLOG(5, "setting ZSTD_p_windowLog = %u (cdict:%u)",
value, (cctx->cdict!=NULL));
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
CLAMPCHECK(value, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
ZSTD_cLevelToCParams(cctx);
cctx->requestedParams.cParams.windowLog = value;
return 0;
case ZSTD_p_hashLog :
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
CLAMPCHECK(value, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
ZSTD_cLevelToCParams(cctx);
cctx->requestedParams.cParams.hashLog = value;
return 0;
case ZSTD_p_chainLog :
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
CLAMPCHECK(value, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
ZSTD_cLevelToCParams(cctx);
cctx->requestedParams.cParams.chainLog = value;
return 0;
case ZSTD_p_searchLog :
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
CLAMPCHECK(value, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
ZSTD_cLevelToCParams(cctx);
cctx->requestedParams.cParams.searchLog = value;
return 0;
case ZSTD_p_minMatch :
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
CLAMPCHECK(value, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
ZSTD_cLevelToCParams(cctx);
cctx->requestedParams.cParams.searchLength = value;
return 0;
case ZSTD_p_targetLength :
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
CLAMPCHECK(value, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
ZSTD_cLevelToCParams(cctx);
cctx->requestedParams.cParams.targetLength = value;
return 0;
case ZSTD_p_compressionStrategy :
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
CLAMPCHECK(value, (unsigned)ZSTD_fast, (unsigned)ZSTD_btultra);
ZSTD_cLevelToCParams(cctx);
cctx->requestedParams.cParams.strategy = (ZSTD_strategy)value;
return 0;
case ZSTD_p_contentSizeFlag :
DEBUGLOG(5, "set content size flag = %u", (value>0));
/* Content size written in frame header _when known_ (default:1) */
cctx->requestedParams.fParams.contentSizeFlag = value>0;
return 0;
case ZSTD_p_checksumFlag :
/* A 32-bits content checksum will be calculated and written at end of frame (default:0) */
cctx->requestedParams.fParams.checksumFlag = value>0;
return 0;
case ZSTD_p_dictIDFlag : /* When applicable, dictionary's dictID is provided in frame header (default:1) */
DEBUGLOG(5, "set dictIDFlag = %u", (value>0));
cctx->requestedParams.fParams.noDictIDFlag = (value==0);
return 0;
/* Dictionary parameters */
case ZSTD_p_dictMode :
if (cctx->cdict) return ERROR(stage_wrong); /* must be set before loading */
/* restrict dictionary mode, to "rawContent" or "fullDict" only */
ZSTD_STATIC_ASSERT((U32)ZSTD_dm_fullDict > (U32)ZSTD_dm_rawContent);
if (value > (unsigned)ZSTD_dm_fullDict)
return ERROR(compressionParameter_outOfBound);
cctx->dictMode = (ZSTD_dictMode_e)value;
return 0;
case ZSTD_p_refDictContent :
if (cctx->cdict) return ERROR(stage_wrong); /* must be set before loading */
/* dictionary content will be referenced, instead of copied */
cctx->dictContentByRef = value>0;
return 0;
case ZSTD_p_forceMaxWindow : /* Force back-references to remain < windowSize,
* even when referencing into Dictionary content
* default : 0 when using a CDict, 1 when using a Prefix */
cctx->forceWindow = value>0;
cctx->loadedDictEnd = 0;
return 0;
case ZSTD_p_nbThreads:
if (value==0) return 0;
DEBUGLOG(5, " setting nbThreads : %u", value);
#ifndef ZSTD_MULTITHREAD
if (value > 1) return ERROR(compressionParameter_unsupported);
#endif
if ((value>1) && (cctx->nbThreads != value)) {
if (cctx->staticSize) /* MT not compatible with static alloc */
return ERROR(compressionParameter_unsupported);
ZSTDMT_freeCCtx(cctx->mtctx);
cctx->nbThreads = 1;
cctx->mtctx = ZSTDMT_createCCtx(value);
if (cctx->mtctx == NULL) return ERROR(memory_allocation);
}
cctx->nbThreads = value;
return 0;
case ZSTD_p_jobSize:
if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
assert(cctx->mtctx != NULL);
return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_sectionSize, value);
case ZSTD_p_overlapSizeLog:
DEBUGLOG(5, " setting overlap with nbThreads == %u", cctx->nbThreads);
if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
assert(cctx->mtctx != NULL);
return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_overlapSectionLog, value);
default: return ERROR(parameter_unknown);
}
}
ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize)
{
DEBUGLOG(5, " setting pledgedSrcSize to %u", (U32)pledgedSrcSize);
if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
cctx->pledgedSrcSizePlusOne = pledgedSrcSize+1;
return 0;
}
ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize)
{
if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
if (cctx->staticSize) return ERROR(memory_allocation); /* no malloc for static CCtx */
DEBUGLOG(5, "load dictionary of size %u", (U32)dictSize);
ZSTD_freeCDict(cctx->cdictLocal); /* in case one already exists */
if (dict==NULL || dictSize==0) { /* no dictionary mode */
cctx->cdictLocal = NULL;
cctx->cdict = NULL;
} else {
ZSTD_compressionParameters const cParams =
cctx->compressionLevel == ZSTD_CLEVEL_CUSTOM ?
cctx->requestedParams.cParams :
ZSTD_getCParams(cctx->compressionLevel, 0, dictSize);
cctx->cdictLocal = ZSTD_createCDict_advanced(
dict, dictSize,
cctx->dictContentByRef, cctx->dictMode,
cParams, cctx->customMem);
cctx->cdict = cctx->cdictLocal;
if (cctx->cdictLocal == NULL)
return ERROR(memory_allocation);
}
return 0;
}
size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict)
{
if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
cctx->cdict = cdict;
cctx->prefix = NULL; /* exclusive */
cctx->prefixSize = 0;
return 0;
}
size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize)
{
if (cctx->streamStage != zcss_init) return ERROR(stage_wrong);
cctx->cdict = NULL; /* prefix discards any prior cdict */
cctx->prefix = prefix;
cctx->prefixSize = prefixSize;
return 0;
}
static void ZSTD_startNewCompression(ZSTD_CCtx* cctx)
{
cctx->streamStage = zcss_init;
cctx->pledgedSrcSizePlusOne = 0;
}
/*! ZSTD_CCtx_reset() :
* Also dumps dictionary */
void ZSTD_CCtx_reset(ZSTD_CCtx* cctx)
{
ZSTD_startNewCompression(cctx);
cctx->cdict = NULL;
}
/** ZSTD_checkCParams() :
control CParam values remain within authorized range.
@return : 0, or an error code if one value is beyond authorized range */
size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams)
{
CLAMPCHECK(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
CLAMPCHECK(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
CLAMPCHECK(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
CLAMPCHECK(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
if ((U32)(cParams.strategy) > (U32)ZSTD_btultra) return ERROR(compressionParameter_unsupported);
return 0;
}
/** ZSTD_clampCParams() :
* make CParam values within valid range.
* @return : valid CParams */
static ZSTD_compressionParameters ZSTD_clampCParams(ZSTD_compressionParameters cParams)
{
# define CLAMP(val,min,max) { \
if (val<min) val=min; \
else if (val>max) val=max; \
}
CLAMP(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
CLAMP(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
CLAMP(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
CLAMP(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
CLAMP(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
CLAMP(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
if ((U32)(cParams.strategy) > (U32)ZSTD_btultra) cParams.strategy = ZSTD_btultra;
return cParams;
}
/** ZSTD_cycleLog() :
* condition for correct operation : hashLog > 1 */
static U32 ZSTD_cycleLog(U32 hashLog, ZSTD_strategy strat)
{
U32 const btScale = ((U32)strat >= (U32)ZSTD_btlazy2);
return hashLog - btScale;
}
/** ZSTD_adjustCParams_internal() :
optimize `cPar` for a given input (`srcSize` and `dictSize`).
mostly downsizing to reduce memory consumption and initialization.
Both `srcSize` and `dictSize` are optional (use 0 if unknown),
but if both are 0, no optimization can be done.
Note : cPar is considered validated at this stage. Use ZSTD_checkParams() to ensure that. */
ZSTD_compressionParameters ZSTD_adjustCParams_internal(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
{
assert(ZSTD_checkCParams(cPar)==0);
if (srcSize+dictSize == 0) return cPar; /* no size information available : no adjustment */
/* resize params, to use less memory when necessary */
{ U32 const minSrcSize = (srcSize==0) ? 500 : 0;
U64 const rSize = srcSize + dictSize + minSrcSize;
if (rSize < ((U64)1<<ZSTD_WINDOWLOG_MAX)) {
U32 const srcLog = MAX(ZSTD_HASHLOG_MIN, ZSTD_highbit32((U32)(rSize)-1) + 1);
if (cPar.windowLog > srcLog) cPar.windowLog = srcLog;
} }
if (cPar.hashLog > cPar.windowLog) cPar.hashLog = cPar.windowLog;
{ U32 const cycleLog = ZSTD_cycleLog(cPar.chainLog, cPar.strategy);
if (cycleLog > cPar.windowLog) cPar.chainLog -= (cycleLog - cPar.windowLog);
}
if (cPar.windowLog < ZSTD_WINDOWLOG_ABSOLUTEMIN) cPar.windowLog = ZSTD_WINDOWLOG_ABSOLUTEMIN; /* required for frame header */
return cPar;
}
ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
{
cPar = ZSTD_clampCParams(cPar);
return ZSTD_adjustCParams_internal(cPar, srcSize, dictSize);
}
size_t ZSTD_estimateCCtxSize_advanced(ZSTD_compressionParameters cParams)
{
size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << cParams.windowLog);
U32 const divider = (cParams.searchLength==3) ? 3 : 4;
size_t const maxNbSeq = blockSize / divider;
size_t const tokenSpace = blockSize + 11*maxNbSeq;
size_t const chainSize = (cParams.strategy == ZSTD_fast) ? 0 : (1 << cParams.chainLog);
size_t const hSize = ((size_t)1) << cParams.hashLog;
U32 const hashLog3 = (cParams.searchLength>3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, cParams.windowLog);
size_t const h3Size = ((size_t)1) << hashLog3;
size_t const entropySpace = hufCTable_size + litlengthCTable_size
+ offcodeCTable_size + matchlengthCTable_size
+ entropyScratchSpace_size;
size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
size_t const optBudget = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
+ (ZSTD_OPT_NUM+1)*(sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
size_t const optSpace = ((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btultra)) ? optBudget : 0;
size_t const neededSpace = entropySpace + tableSpace + tokenSpace + optSpace;
DEBUGLOG(5, "sizeof(ZSTD_CCtx) : %u", (U32)sizeof(ZSTD_CCtx));
DEBUGLOG(5, "estimate workSpace : %u", (U32)neededSpace);
return sizeof(ZSTD_CCtx) + neededSpace;
}
size_t ZSTD_estimateCCtxSize(int compressionLevel)
{
ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, 0);
return ZSTD_estimateCCtxSize_advanced(cParams);
}
size_t ZSTD_estimateCStreamSize_advanced(ZSTD_compressionParameters cParams)
{
size_t const CCtxSize = ZSTD_estimateCCtxSize_advanced(cParams);
size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << cParams.windowLog);
size_t const inBuffSize = ((size_t)1 << cParams.windowLog) + blockSize;
size_t const outBuffSize = ZSTD_compressBound(blockSize) + 1;
size_t const streamingSize = inBuffSize + outBuffSize;
return CCtxSize + streamingSize;
}
size_t ZSTD_estimateCStreamSize(int compressionLevel) {
ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, 0);
return ZSTD_estimateCStreamSize_advanced(cParams);
}
static U32 ZSTD_equivalentParams(ZSTD_compressionParameters cParams1,
ZSTD_compressionParameters cParams2)
{
U32 bslog1 = MIN(cParams1.windowLog, ZSTD_BLOCKSIZELOG_MAX);
U32 bslog2 = MIN(cParams2.windowLog, ZSTD_BLOCKSIZELOG_MAX);
return (bslog1 == bslog2) /* same block size */
& (cParams1.hashLog == cParams2.hashLog)
& (cParams1.chainLog == cParams2.chainLog)
& (cParams1.strategy == cParams2.strategy) /* opt parser space */
& ((cParams1.searchLength==3) == (cParams2.searchLength==3)); /* hashlog3 space */
}
/*! ZSTD_continueCCtx() :
* reuse CCtx without reset (note : requires no dictionary) */
static size_t ZSTD_continueCCtx(ZSTD_CCtx* cctx, ZSTD_parameters params, U64 pledgedSrcSize)
{
U32 const end = (U32)(cctx->nextSrc - cctx->base);
DEBUGLOG(5, "continue mode");
cctx->appliedParams = params;
cctx->pledgedSrcSizePlusOne = pledgedSrcSize+1;
cctx->consumedSrcSize = 0;
if (pledgedSrcSize == ZSTD_CONTENTSIZE_UNKNOWN)
cctx->appliedParams.fParams.contentSizeFlag = 0;
DEBUGLOG(5, "pledged content size : %u ; flag : %u",
(U32)pledgedSrcSize, cctx->appliedParams.fParams.contentSizeFlag);
cctx->lowLimit = end;
cctx->dictLimit = end;
cctx->nextToUpdate = end+1;
cctx->stage = ZSTDcs_init;
cctx->dictID = 0;
cctx->loadedDictEnd = 0;
{ int i; for (i=0; i<ZSTD_REP_NUM; i++) cctx->rep[i] = repStartValue[i]; }
cctx->seqStore.litLengthSum = 0; /* force reset of btopt stats */
XXH64_reset(&cctx->xxhState, 0);
return 0;
}
typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset } ZSTD_compResetPolicy_e;
typedef enum { ZSTDb_not_buffered, ZSTDb_buffered } ZSTD_buffered_policy_e;
/*! ZSTD_resetCCtx_internal() :
note : `params` are assumed fully validated at this stage */
static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
ZSTD_parameters params, U64 pledgedSrcSize,
ZSTD_compResetPolicy_e const crp,
ZSTD_buffered_policy_e const zbuff)
{
assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
if (crp == ZSTDcrp_continue) {
if (ZSTD_equivalentParams(params.cParams, zc->appliedParams.cParams)) {
DEBUGLOG(5, "ZSTD_equivalentParams()==1");
zc->fseCTables_ready = 0;
zc->hufCTable_repeatMode = HUF_repeat_none;
return ZSTD_continueCCtx(zc, params, pledgedSrcSize);
} }
{ size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << params.cParams.windowLog);
U32 const divider = (params.cParams.searchLength==3) ? 3 : 4;
size_t const maxNbSeq = blockSize / divider;
size_t const tokenSpace = blockSize + 11*maxNbSeq;
size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ?
0 : (1 << params.cParams.chainLog);
size_t const hSize = ((size_t)1) << params.cParams.hashLog;
U32 const hashLog3 = (params.cParams.searchLength>3) ?
0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog);
size_t const h3Size = ((size_t)1) << hashLog3;
size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
size_t const buffOutSize = (zbuff==ZSTDb_buffered) ? ZSTD_compressBound(blockSize)+1 : 0;
size_t const buffInSize = (zbuff==ZSTDb_buffered) ? ((size_t)1 << params.cParams.windowLog) + blockSize : 0;
void* ptr;
/* Check if workSpace is large enough, alloc a new one if needed */
{ size_t const entropySpace = hufCTable_size + litlengthCTable_size
+ offcodeCTable_size + matchlengthCTable_size
+ entropyScratchSpace_size;
size_t const optPotentialSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits)) * sizeof(U32)
+ (ZSTD_OPT_NUM+1) * (sizeof(ZSTD_match_t)+sizeof(ZSTD_optimal_t));
size_t const optSpace = ( (params.cParams.strategy == ZSTD_btopt)
|| (params.cParams.strategy == ZSTD_btultra)) ?
optPotentialSpace : 0;
size_t const bufferSpace = buffInSize + buffOutSize;
size_t const neededSpace = entropySpace + optSpace + tableSpace
+ tokenSpace + bufferSpace;
if (zc->workSpaceSize < neededSpace) { /* too small : resize /*/
DEBUGLOG(5, "Need to update workSpaceSize from %uK to %uK \n",
(unsigned)zc->workSpaceSize>>10,
(unsigned)neededSpace>>10);
/* static cctx : no resize, error out */
if (zc->staticSize) return ERROR(memory_allocation);
zc->workSpaceSize = 0;
ZSTD_free(zc->workSpace, zc->customMem);
zc->workSpace = ZSTD_malloc(neededSpace, zc->customMem);
if (zc->workSpace == NULL) return ERROR(memory_allocation);
zc->workSpaceSize = neededSpace;
ptr = zc->workSpace;
/* entropy space */
zc->hufCTable = (HUF_CElt*)ptr;
ptr = (char*)zc->hufCTable + hufCTable_size; /* note : HUF_CElt* is incomplete type, size is estimated via macro */
zc->offcodeCTable = (FSE_CTable*) ptr;
ptr = (char*)ptr + offcodeCTable_size;
zc->matchlengthCTable = (FSE_CTable*) ptr;
ptr = (char*)ptr + matchlengthCTable_size;
zc->litlengthCTable = (FSE_CTable*) ptr;
ptr = (char*)ptr + litlengthCTable_size;
assert(((size_t)ptr & 3) == 0); /* ensure correct alignment */
zc->entropyScratchSpace = (unsigned*) ptr;
} }
/* init params */
zc->appliedParams = params;
zc->pledgedSrcSizePlusOne = pledgedSrcSize+1;
zc->consumedSrcSize = 0;
if (pledgedSrcSize == ZSTD_CONTENTSIZE_UNKNOWN)
zc->appliedParams.fParams.contentSizeFlag = 0;
DEBUGLOG(5, "pledged content size : %u ; flag : %u",
(U32)pledgedSrcSize, zc->appliedParams.fParams.contentSizeFlag);
zc->blockSize = blockSize;
XXH64_reset(&zc->xxhState, 0);
zc->stage = ZSTDcs_init;
zc->dictID = 0;
zc->loadedDictEnd = 0;
zc->fseCTables_ready = 0;
zc->hufCTable_repeatMode = HUF_repeat_none;
zc->nextToUpdate = 1;
zc->nextSrc = NULL;
zc->base = NULL;
zc->dictBase = NULL;
zc->dictLimit = 0;
zc->lowLimit = 0;
{ int i; for (i=0; i<ZSTD_REP_NUM; i++) zc->rep[i] = repStartValue[i]; }
zc->hashLog3 = hashLog3;
zc->seqStore.litLengthSum = 0;
/* ensure entropy tables are close together at the beginning */
assert((void*)zc->hufCTable == zc->workSpace);
assert((char*)zc->offcodeCTable == (char*)zc->hufCTable + hufCTable_size);
assert((char*)zc->matchlengthCTable == (char*)zc->offcodeCTable + offcodeCTable_size);
assert((char*)zc->litlengthCTable == (char*)zc->matchlengthCTable + matchlengthCTable_size);
assert((char*)zc->entropyScratchSpace == (char*)zc->litlengthCTable + litlengthCTable_size);
ptr = (char*)zc->entropyScratchSpace + entropyScratchSpace_size;
/* opt parser space */
if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btultra)) {
DEBUGLOG(5, "reserving optimal parser space");
assert(((size_t)ptr & 3) == 0); /* ensure ptr is properly aligned */
zc->seqStore.litFreq = (U32*)ptr;
zc->seqStore.litLengthFreq = zc->seqStore.litFreq + (1<<Litbits);
zc->seqStore.matchLengthFreq = zc->seqStore.litLengthFreq + (MaxLL+1);
zc->seqStore.offCodeFreq = zc->seqStore.matchLengthFreq + (MaxML+1);
ptr = zc->seqStore.offCodeFreq + (MaxOff+1);
zc->seqStore.matchTable = (ZSTD_match_t*)ptr;
ptr = zc->seqStore.matchTable + ZSTD_OPT_NUM+1;
zc->seqStore.priceTable = (ZSTD_optimal_t*)ptr;
ptr = zc->seqStore.priceTable + ZSTD_OPT_NUM+1;
}
/* table Space */
if (crp!=ZSTDcrp_noMemset) memset(ptr, 0, tableSpace); /* reset tables only */
assert(((size_t)ptr & 3) == 0); /* ensure ptr is properly aligned */
zc->hashTable = (U32*)(ptr);
zc->chainTable = zc->hashTable + hSize;
zc->hashTable3 = zc->chainTable + chainSize;
ptr = zc->hashTable3 + h3Size;
/* sequences storage */
zc->seqStore.sequencesStart = (seqDef*)ptr;
ptr = zc->seqStore.sequencesStart + maxNbSeq;
zc->seqStore.llCode = (BYTE*) ptr;
zc->seqStore.mlCode = zc->seqStore.llCode + maxNbSeq;
zc->seqStore.ofCode = zc->seqStore.mlCode + maxNbSeq;
zc->seqStore.litStart = zc->seqStore.ofCode + maxNbSeq;
ptr = zc->seqStore.litStart + blockSize;
/* buffers */
zc->inBuffSize = buffInSize;
zc->inBuff = (char*)ptr;
zc->outBuffSize = buffOutSize;
zc->outBuff = zc->inBuff + buffInSize;
return 0;
}
}
/* ZSTD_invalidateRepCodes() :
* ensures next compression will not use repcodes from previous block.
* Note : only works with regular variant;
* do not use with extDict variant ! */
void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx) {
int i;
for (i=0; i<ZSTD_REP_NUM; i++) cctx->rep[i] = 0;
}
/*! ZSTD_copyCCtx_internal() :
* Duplicate an existing context `srcCCtx` into another one `dstCCtx`.
* Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()).
* pledgedSrcSize=0 means "empty" if fParams.contentSizeFlag=1
* @return : 0, or an error code */
static size_t ZSTD_copyCCtx_internal(ZSTD_CCtx* dstCCtx,
const ZSTD_CCtx* srcCCtx,
ZSTD_frameParameters fParams,
unsigned long long pledgedSrcSize,
ZSTD_buffered_policy_e zbuff)
{
DEBUGLOG(5, "ZSTD_copyCCtx_internal");
if (srcCCtx->stage!=ZSTDcs_init) return ERROR(stage_wrong);
memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem));
{ ZSTD_parameters params = srcCCtx->appliedParams;
params.fParams = fParams;
ZSTD_resetCCtx_internal(dstCCtx, params, pledgedSrcSize,
ZSTDcrp_noMemset, zbuff);
}
/* copy tables */
{ size_t const chainSize = (srcCCtx->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->appliedParams.cParams.chainLog);
size_t const hSize = (size_t)1 << srcCCtx->appliedParams.cParams.hashLog;
size_t const h3Size = (size_t)1 << srcCCtx->hashLog3;
size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
assert((U32*)dstCCtx->chainTable == (U32*)dstCCtx->hashTable + hSize); /* chainTable must follow hashTable */
assert((U32*)dstCCtx->hashTable3 == (U32*)dstCCtx->chainTable + chainSize);
memcpy(dstCCtx->hashTable, srcCCtx->hashTable, tableSpace); /* presumes all tables follow each other */
}
/* copy dictionary offsets */
dstCCtx->nextToUpdate = srcCCtx->nextToUpdate;
dstCCtx->nextToUpdate3= srcCCtx->nextToUpdate3;
dstCCtx->nextSrc = srcCCtx->nextSrc;
dstCCtx->base = srcCCtx->base;
dstCCtx->dictBase = srcCCtx->dictBase;
dstCCtx->dictLimit = srcCCtx->dictLimit;
dstCCtx->lowLimit = srcCCtx->lowLimit;
dstCCtx->loadedDictEnd= srcCCtx->loadedDictEnd;
dstCCtx->dictID = srcCCtx->dictID;
/* copy entropy tables */
dstCCtx->fseCTables_ready = srcCCtx->fseCTables_ready;
if (srcCCtx->fseCTables_ready) {
memcpy(dstCCtx->litlengthCTable, srcCCtx->litlengthCTable, litlengthCTable_size);
memcpy(dstCCtx->matchlengthCTable, srcCCtx->matchlengthCTable, matchlengthCTable_size);
memcpy(dstCCtx->offcodeCTable, srcCCtx->offcodeCTable, offcodeCTable_size);
}
dstCCtx->hufCTable_repeatMode = srcCCtx->hufCTable_repeatMode;
if (srcCCtx->hufCTable_repeatMode) {
memcpy(dstCCtx->hufCTable, srcCCtx->hufCTable, hufCTable_size);
}
return 0;
}
/*! ZSTD_copyCCtx() :
* Duplicate an existing context `srcCCtx` into another one `dstCCtx`.
* Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()).
* pledgedSrcSize==0 means "unknown".
* @return : 0, or an error code */
size_t ZSTD_copyCCtx(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx, unsigned long long pledgedSrcSize)
{
ZSTD_frameParameters fParams = { 1 /*content*/, 0 /*checksum*/, 0 /*noDictID*/ };
ZSTD_buffered_policy_e const zbuff = (ZSTD_buffered_policy_e)(srcCCtx->inBuffSize>0);
ZSTD_STATIC_ASSERT((U32)ZSTDb_buffered==1);
fParams.contentSizeFlag = pledgedSrcSize>0;
return ZSTD_copyCCtx_internal(dstCCtx, srcCCtx, fParams, pledgedSrcSize, zbuff);
}
/*! ZSTD_reduceTable() :
* reduce table indexes by `reducerValue` */
static void ZSTD_reduceTable (U32* const table, U32 const size, U32 const reducerValue)
{
U32 u;
for (u=0 ; u < size ; u++) {
if (table[u] < reducerValue) table[u] = 0;
else table[u] -= reducerValue;
}
}
/*! ZSTD_reduceIndex() :
* rescale all indexes to avoid future overflow (indexes are U32) */
static void ZSTD_reduceIndex (ZSTD_CCtx* zc, const U32 reducerValue)
{
{ U32 const hSize = 1 << zc->appliedParams.cParams.hashLog;
ZSTD_reduceTable(zc->hashTable, hSize, reducerValue); }
{ U32 const chainSize = (zc->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->appliedParams.cParams.chainLog);
ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue); }
{ U32 const h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0;
ZSTD_reduceTable(zc->hashTable3, h3Size, reducerValue); }
}
/*-*******************************************************
* Block entropic compression
*********************************************************/
/* See doc/zstd_compression_format.md for detailed format description */
size_t ZSTD_noCompressBlock (void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
if (srcSize + ZSTD_blockHeaderSize > dstCapacity) return ERROR(dstSize_tooSmall);
memcpy((BYTE*)dst + ZSTD_blockHeaderSize, src, srcSize);
MEM_writeLE24(dst, (U32)(srcSize << 2) + (U32)bt_raw);
return ZSTD_blockHeaderSize+srcSize;
}
static size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
BYTE* const ostart = (BYTE* const)dst;
U32 const flSize = 1 + (srcSize>31) + (srcSize>4095);
if (srcSize + flSize > dstCapacity) return ERROR(dstSize_tooSmall);
switch(flSize)
{
case 1: /* 2 - 1 - 5 */
ostart[0] = (BYTE)((U32)set_basic + (srcSize<<3));
break;
case 2: /* 2 - 2 - 12 */
MEM_writeLE16(ostart, (U16)((U32)set_basic + (1<<2) + (srcSize<<4)));
break;
case 3: /* 2 - 2 - 20 */
MEM_writeLE32(ostart, (U32)((U32)set_basic + (3<<2) + (srcSize<<4)));
break;
default: /* not necessary : flSize is {1,2,3} */
assert(0);
}
memcpy(ostart + flSize, src, srcSize);
return srcSize + flSize;
}
static size_t ZSTD_compressRleLiteralsBlock (void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
BYTE* const ostart = (BYTE* const)dst;
U32 const flSize = 1 + (srcSize>31) + (srcSize>4095);
(void)dstCapacity; /* dstCapacity already guaranteed to be >=4, hence large enough */
switch(flSize)
{
case 1: /* 2 - 1 - 5 */
ostart[0] = (BYTE)((U32)set_rle + (srcSize<<3));
break;
case 2: /* 2 - 2 - 12 */
MEM_writeLE16(ostart, (U16)((U32)set_rle + (1<<2) + (srcSize<<4)));
break;
case 3: /* 2 - 2 - 20 */
MEM_writeLE32(ostart, (U32)((U32)set_rle + (3<<2) + (srcSize<<4)));
break;
default: /* not necessary : flSize is {1,2,3} */
assert(0);
}
ostart[flSize] = *(const BYTE*)src;
return flSize+1;
}
static size_t ZSTD_minGain(size_t srcSize) { return (srcSize >> 6) + 2; }
static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize)
{
size_t const minGain = ZSTD_minGain(srcSize);
size_t const lhSize = 3 + (srcSize >= 1 KB) + (srcSize >= 16 KB);
BYTE* const ostart = (BYTE*)dst;
U32 singleStream = srcSize < 256;
symbolEncodingType_e hType = set_compressed;
size_t cLitSize;
/* small ? don't even attempt compression (speed opt) */
# define LITERAL_NOENTROPY 63
{ size_t const minLitSize = zc->hufCTable_repeatMode == HUF_repeat_valid ? 6 : LITERAL_NOENTROPY;
if (srcSize <= minLitSize) return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize);
}
if (dstCapacity < lhSize+1) return ERROR(dstSize_tooSmall); /* not enough space for compression */
{ HUF_repeat repeat = zc->hufCTable_repeatMode;
int const preferRepeat = zc->appliedParams.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0;
if (repeat == HUF_repeat_valid && lhSize == 3) singleStream = 1;
cLitSize = singleStream ? HUF_compress1X_repeat(ostart+lhSize, dstCapacity-lhSize, src, srcSize, 255, 11,
zc->entropyScratchSpace, entropyScratchSpace_size, zc->hufCTable, &repeat, preferRepeat)
: HUF_compress4X_repeat(ostart+lhSize, dstCapacity-lhSize, src, srcSize, 255, 11,
zc->entropyScratchSpace, entropyScratchSpace_size, zc->hufCTable, &repeat, preferRepeat);
if (repeat != HUF_repeat_none) { hType = set_repeat; } /* reused the existing table */
else { zc->hufCTable_repeatMode = HUF_repeat_check; } /* now have a table to reuse */
}
if ((cLitSize==0) | (cLitSize >= srcSize - minGain)) {
zc->hufCTable_repeatMode = HUF_repeat_none;
return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize);
}
if (cLitSize==1) {
zc->hufCTable_repeatMode = HUF_repeat_none;
return ZSTD_compressRleLiteralsBlock(dst, dstCapacity, src, srcSize);
}
/* Build header */
switch(lhSize)
{
case 3: /* 2 - 2 - 10 - 10 */
{ U32 const lhc = hType + ((!singleStream) << 2) + ((U32)srcSize<<4) + ((U32)cLitSize<<14);
MEM_writeLE24(ostart, lhc);
break;
}
case 4: /* 2 - 2 - 14 - 14 */
{ U32 const lhc = hType + (2 << 2) + ((U32)srcSize<<4) + ((U32)cLitSize<<18);
MEM_writeLE32(ostart, lhc);
break;
}
case 5: /* 2 - 2 - 18 - 18 */
{ U32 const lhc = hType + (3 << 2) + ((U32)srcSize<<4) + ((U32)cLitSize<<22);
MEM_writeLE32(ostart, lhc);
ostart[4] = (BYTE)(cLitSize >> 10);
break;
}
default: /* not possible : lhSize is {3,4,5} */
assert(0);
}
return lhSize+cLitSize;
}
static const BYTE LL_Code[64] = { 0, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
16, 16, 17, 17, 18, 18, 19, 19,
20, 20, 20, 20, 21, 21, 21, 21,
22, 22, 22, 22, 22, 22, 22, 22,
23, 23, 23, 23, 23, 23, 23, 23,
24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24 };
static const BYTE ML_Code[128] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 32, 33, 33, 34, 34, 35, 35, 36, 36, 36, 36, 37, 37, 37, 37,
38, 38, 38, 38, 38, 38, 38, 38, 39, 39, 39, 39, 39, 39, 39, 39,
40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41,
42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42,
42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42 };
void ZSTD_seqToCodes(const seqStore_t* seqStorePtr)
{
BYTE const LL_deltaCode = 19;
BYTE const ML_deltaCode = 36;
const seqDef* const sequences = seqStorePtr->sequencesStart;
BYTE* const llCodeTable = seqStorePtr->llCode;
BYTE* const ofCodeTable = seqStorePtr->ofCode;
BYTE* const mlCodeTable = seqStorePtr->mlCode;
U32 const nbSeq = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
U32 u;
for (u=0; u<nbSeq; u++) {
U32 const llv = sequences[u].litLength;
U32 const mlv = sequences[u].matchLength;
llCodeTable[u] = (llv> 63) ? (BYTE)ZSTD_highbit32(llv) + LL_deltaCode : LL_Code[llv];
ofCodeTable[u] = (BYTE)ZSTD_highbit32(sequences[u].offset);
mlCodeTable[u] = (mlv>127) ? (BYTE)ZSTD_highbit32(mlv) + ML_deltaCode : ML_Code[mlv];
}
if (seqStorePtr->longLengthID==1)
llCodeTable[seqStorePtr->longLengthPos] = MaxLL;
if (seqStorePtr->longLengthID==2)
mlCodeTable[seqStorePtr->longLengthPos] = MaxML;
}
MEM_STATIC size_t ZSTD_compressSequences (ZSTD_CCtx* zc,
void* dst, size_t dstCapacity,
size_t srcSize)
{
const int longOffsets = zc->appliedParams.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
const seqStore_t* seqStorePtr = &(zc->seqStore);
U32 count[MaxSeq+1];
S16 norm[MaxSeq+1];
FSE_CTable* CTable_LitLength = zc->litlengthCTable;
FSE_CTable* CTable_OffsetBits = zc->offcodeCTable;
FSE_CTable* CTable_MatchLength = zc->matchlengthCTable;
U32 LLtype, Offtype, MLtype; /* compressed, raw or rle */
const seqDef* const sequences = seqStorePtr->sequencesStart;
const BYTE* const ofCodeTable = seqStorePtr->ofCode;
const BYTE* const llCodeTable = seqStorePtr->llCode;
const BYTE* const mlCodeTable = seqStorePtr->mlCode;
BYTE* const ostart = (BYTE*)dst;
BYTE* const oend = ostart + dstCapacity;
BYTE* op = ostart;
size_t const nbSeq = seqStorePtr->sequences - seqStorePtr->sequencesStart;
BYTE* seqHead;
BYTE scratchBuffer[1<<MAX(MLFSELog,LLFSELog)];
/* Compress literals */
{ const BYTE* const literals = seqStorePtr->litStart;
size_t const litSize = seqStorePtr->lit - literals;
size_t const cSize = ZSTD_compressLiterals(zc, op, dstCapacity, literals, litSize);
if (ZSTD_isError(cSize)) return cSize;
op += cSize;
}
/* Sequences Header */
if ((oend-op) < 3 /*max nbSeq Size*/ + 1 /*seqHead */) return ERROR(dstSize_tooSmall);
if (nbSeq < 0x7F) *op++ = (BYTE)nbSeq;
else if (nbSeq < LONGNBSEQ) op[0] = (BYTE)((nbSeq>>8) + 0x80), op[1] = (BYTE)nbSeq, op+=2;
else op[0]=0xFF, MEM_writeLE16(op+1, (U16)(nbSeq - LONGNBSEQ)), op+=3;
if (nbSeq==0) goto _check_compressibility;
/* seqHead : flags for FSE encoding type */
seqHead = op++;
#define MIN_SEQ_FOR_DYNAMIC_FSE 64
#define MAX_SEQ_FOR_STATIC_FSE 1000
/* convert length/distances into codes */
ZSTD_seqToCodes(seqStorePtr);
/* CTable for Literal Lengths */
{ U32 max = MaxLL;
size_t const mostFrequent = FSE_countFast_wksp(count, &max, llCodeTable, nbSeq, zc->entropyScratchSpace);
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
*op++ = llCodeTable[0];
FSE_buildCTable_rle(CTable_LitLength, (BYTE)max);
LLtype = set_rle;
} else if ((zc->fseCTables_ready) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
LLtype = set_repeat;
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (LL_defaultNormLog-1)))) {
FSE_buildCTable_wksp(CTable_LitLength, LL_defaultNorm, MaxLL, LL_defaultNormLog, scratchBuffer, sizeof(scratchBuffer));
LLtype = set_basic;
} else {
size_t nbSeq_1 = nbSeq;
const U32 tableLog = FSE_optimalTableLog(LLFSELog, nbSeq, max);
if (count[llCodeTable[nbSeq-1]]>1) { count[llCodeTable[nbSeq-1]]--; nbSeq_1--; }
FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
{ size_t const NCountSize = FSE_writeNCount(op, oend-op, norm, max, tableLog); /* overflow protected */
if (FSE_isError(NCountSize)) return NCountSize;
op += NCountSize; }
FSE_buildCTable_wksp(CTable_LitLength, norm, max, tableLog, scratchBuffer, sizeof(scratchBuffer));
LLtype = set_compressed;
} }
/* CTable for Offsets */
{ U32 max = MaxOff;
size_t const mostFrequent = FSE_countFast_wksp(count, &max, ofCodeTable, nbSeq, zc->entropyScratchSpace);
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
*op++ = ofCodeTable[0];
FSE_buildCTable_rle(CTable_OffsetBits, (BYTE)max);
Offtype = set_rle;
} else if ((zc->fseCTables_ready) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
Offtype = set_repeat;
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (OF_defaultNormLog-1)))) {
FSE_buildCTable_wksp(CTable_OffsetBits, OF_defaultNorm, MaxOff, OF_defaultNormLog, scratchBuffer, sizeof(scratchBuffer));
Offtype = set_basic;
} else {
size_t nbSeq_1 = nbSeq;
const U32 tableLog = FSE_optimalTableLog(OffFSELog, nbSeq, max);
if (count[ofCodeTable[nbSeq-1]]>1) { count[ofCodeTable[nbSeq-1]]--; nbSeq_1--; }
FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
{ size_t const NCountSize = FSE_writeNCount(op, oend-op, norm, max, tableLog); /* overflow protected */
if (FSE_isError(NCountSize)) return NCountSize;
op += NCountSize; }
FSE_buildCTable_wksp(CTable_OffsetBits, norm, max, tableLog, scratchBuffer, sizeof(scratchBuffer));
Offtype = set_compressed;
} }
/* CTable for MatchLengths */
{ U32 max = MaxML;
size_t const mostFrequent = FSE_countFast_wksp(count, &max, mlCodeTable, nbSeq, zc->entropyScratchSpace);
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
*op++ = *mlCodeTable;
FSE_buildCTable_rle(CTable_MatchLength, (BYTE)max);
MLtype = set_rle;
} else if ((zc->fseCTables_ready) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
MLtype = set_repeat;
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (ML_defaultNormLog-1)))) {
FSE_buildCTable_wksp(CTable_MatchLength, ML_defaultNorm, MaxML, ML_defaultNormLog, scratchBuffer, sizeof(scratchBuffer));
MLtype = set_basic;
} else {
size_t nbSeq_1 = nbSeq;
const U32 tableLog = FSE_optimalTableLog(MLFSELog, nbSeq, max);
if (count[mlCodeTable[nbSeq-1]]>1) { count[mlCodeTable[nbSeq-1]]--; nbSeq_1--; }
FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
{ size_t const NCountSize = FSE_writeNCount(op, oend-op, norm, max, tableLog); /* overflow protected */
if (FSE_isError(NCountSize)) return NCountSize;
op += NCountSize; }
FSE_buildCTable_wksp(CTable_MatchLength, norm, max, tableLog, scratchBuffer, sizeof(scratchBuffer));
MLtype = set_compressed;
} }
*seqHead = (BYTE)((LLtype<<6) + (Offtype<<4) + (MLtype<<2));
zc->fseCTables_ready = 0;
/* Encoding Sequences */
{ BIT_CStream_t blockStream;
FSE_CState_t stateMatchLength;
FSE_CState_t stateOffsetBits;
FSE_CState_t stateLitLength;
CHECK_E(BIT_initCStream(&blockStream, op, oend-op), dstSize_tooSmall); /* not enough space remaining */
/* first symbols */
FSE_initCState2(&stateMatchLength, CTable_MatchLength, mlCodeTable[nbSeq-1]);
FSE_initCState2(&stateOffsetBits, CTable_OffsetBits, ofCodeTable[nbSeq-1]);
FSE_initCState2(&stateLitLength, CTable_LitLength, llCodeTable[nbSeq-1]);
BIT_addBits(&blockStream, sequences[nbSeq-1].litLength, LL_bits[llCodeTable[nbSeq-1]]);
if (MEM_32bits()) BIT_flushBits(&blockStream);
BIT_addBits(&blockStream, sequences[nbSeq-1].matchLength, ML_bits[mlCodeTable[nbSeq-1]]);
if (MEM_32bits()) BIT_flushBits(&blockStream);
if (longOffsets) {
U32 const ofBits = ofCodeTable[nbSeq-1];
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
if (extraBits) {
BIT_addBits(&blockStream, sequences[nbSeq-1].offset, extraBits);
BIT_flushBits(&blockStream);
}
BIT_addBits(&blockStream, sequences[nbSeq-1].offset >> extraBits,
ofBits - extraBits);
} else {
BIT_addBits(&blockStream, sequences[nbSeq-1].offset, ofCodeTable[nbSeq-1]);
}
BIT_flushBits(&blockStream);
{ size_t n;
for (n=nbSeq-2 ; n<nbSeq ; n--) { /* intentional underflow */
BYTE const llCode = llCodeTable[n];
BYTE const ofCode = ofCodeTable[n];
BYTE const mlCode = mlCodeTable[n];
U32 const llBits = LL_bits[llCode];
U32 const ofBits = ofCode; /* 32b*/ /* 64b*/
U32 const mlBits = ML_bits[mlCode];
/* (7)*/ /* (7)*/
FSE_encodeSymbol(&blockStream, &stateOffsetBits, ofCode); /* 15 */ /* 15 */
FSE_encodeSymbol(&blockStream, &stateMatchLength, mlCode); /* 24 */ /* 24 */
if (MEM_32bits()) BIT_flushBits(&blockStream); /* (7)*/
FSE_encodeSymbol(&blockStream, &stateLitLength, llCode); /* 16 */ /* 33 */
if (MEM_32bits() || (ofBits+mlBits+llBits >= 64-7-(LLFSELog+MLFSELog+OffFSELog)))
BIT_flushBits(&blockStream); /* (7)*/
BIT_addBits(&blockStream, sequences[n].litLength, llBits);
if (MEM_32bits() && ((llBits+mlBits)>24)) BIT_flushBits(&blockStream);
BIT_addBits(&blockStream, sequences[n].matchLength, mlBits);
if (MEM_32bits()) BIT_flushBits(&blockStream); /* (7)*/
if (longOffsets) {
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
if (extraBits) {
BIT_addBits(&blockStream, sequences[n].offset, extraBits);
BIT_flushBits(&blockStream); /* (7)*/
}
BIT_addBits(&blockStream, sequences[n].offset >> extraBits,
ofBits - extraBits); /* 31 */
} else {
BIT_addBits(&blockStream, sequences[n].offset, ofBits); /* 31 */
}
BIT_flushBits(&blockStream); /* (7)*/
} }
FSE_flushCState(&blockStream, &stateMatchLength);
FSE_flushCState(&blockStream, &stateOffsetBits);
FSE_flushCState(&blockStream, &stateLitLength);
{ size_t const streamSize = BIT_closeCStream(&blockStream);
if (streamSize==0) return ERROR(dstSize_tooSmall); /* not enough space */
op += streamSize;
} }
/* check compressibility */
_check_compressibility:
{ size_t const minGain = ZSTD_minGain(srcSize);
size_t const maxCSize = srcSize - minGain;
if ((size_t)(op-ostart) >= maxCSize) {
zc->hufCTable_repeatMode = HUF_repeat_none;
return 0;
} }
/* confirm repcodes */
{ int i; for (i=0; i<ZSTD_REP_NUM; i++) zc->rep[i] = zc->repToConfirm[i]; }
return op - ostart;
}
/*! ZSTD_storeSeq() :
Store a sequence (literal length, literals, offset code and match length code) into seqStore_t.
`offsetCode` : distance to match, or 0 == repCode.
`matchCode` : matchLength - MINMATCH
*/
MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const void* literals, U32 offsetCode, size_t matchCode)
{
#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG >= 6)
static const BYTE* g_start = NULL;
U32 const pos = (U32)((const BYTE*)literals - g_start);
if (g_start==NULL) g_start = (const BYTE*)literals;
if ((pos > 0) && (pos < 1000000000))
DEBUGLOG(6, "Cpos %6u :%5u literals & match %3u bytes at distance %6u",
pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
#endif
/* copy Literals */
assert(seqStorePtr->lit + litLength <= seqStorePtr->litStart + 128 KB);
ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
seqStorePtr->lit += litLength;
/* literal Length */
if (litLength>0xFFFF) {
seqStorePtr->longLengthID = 1;
seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
}
seqStorePtr->sequences[0].litLength = (U16)litLength;
/* match offset */
seqStorePtr->sequences[0].offset = offsetCode + 1;
/* match Length */
if (matchCode>0xFFFF) {
seqStorePtr->longLengthID = 2;
seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
}
seqStorePtr->sequences[0].matchLength = (U16)matchCode;
seqStorePtr->sequences++;
}
/*-*************************************
* Match length counter
***************************************/
static unsigned ZSTD_NbCommonBytes (register size_t val)
{
if (MEM_isLittleEndian()) {
if (MEM_64bits()) {
# if defined(_MSC_VER) && defined(_WIN64)
unsigned long r = 0;
_BitScanForward64( &r, (U64)val );
return (unsigned)(r>>3);
# elif defined(__GNUC__) && (__GNUC__ >= 3)
return (__builtin_ctzll((U64)val) >> 3);
# else
static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2,
0, 3, 1, 3, 1, 4, 2, 7,
0, 2, 3, 6, 1, 5, 3, 5,
1, 3, 4, 4, 2, 5, 6, 7,
7, 0, 1, 2, 3, 3, 4, 6,
2, 6, 5, 5, 3, 4, 5, 6,
7, 1, 2, 4, 6, 4, 4, 5,
7, 2, 6, 5, 7, 6, 7, 7 };
return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
# endif
} else { /* 32 bits */
# if defined(_MSC_VER)
unsigned long r=0;
_BitScanForward( &r, (U32)val );
return (unsigned)(r>>3);
# elif defined(__GNUC__) && (__GNUC__ >= 3)
return (__builtin_ctz((U32)val) >> 3);
# else
static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0,
3, 2, 2, 1, 3, 2, 0, 1,
3, 3, 1, 2, 2, 2, 2, 0,
3, 1, 2, 0, 1, 0, 1, 1 };
return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
# endif
}
} else { /* Big Endian CPU */
if (MEM_64bits()) {
# if defined(_MSC_VER) && defined(_WIN64)
unsigned long r = 0;
_BitScanReverse64( &r, val );
return (unsigned)(r>>3);
# elif defined(__GNUC__) && (__GNUC__ >= 3)
return (__builtin_clzll(val) >> 3);
# else
unsigned r;
const unsigned n32 = sizeof(size_t)*4; /* calculate this way due to compiler complaining in 32-bits mode */
if (!(val>>n32)) { r=4; } else { r=0; val>>=n32; }
if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
r += (!val);
return r;
# endif
} else { /* 32 bits */
# if defined(_MSC_VER)
unsigned long r = 0;
_BitScanReverse( &r, (unsigned long)val );
return (unsigned)(r>>3);
# elif defined(__GNUC__) && (__GNUC__ >= 3)
return (__builtin_clz((U32)val) >> 3);
# else
unsigned r;
if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
r += (!val);
return r;
# endif
} }
}
static size_t ZSTD_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* const pInLimit)
{
const BYTE* const pStart = pIn;
const BYTE* const pInLoopLimit = pInLimit - (sizeof(size_t)-1);
while (pIn < pInLoopLimit) {
size_t const diff = MEM_readST(pMatch) ^ MEM_readST(pIn);
if (!diff) { pIn+=sizeof(size_t); pMatch+=sizeof(size_t); continue; }
pIn += ZSTD_NbCommonBytes(diff);
return (size_t)(pIn - pStart);
}
if (MEM_64bits()) if ((pIn<(pInLimit-3)) && (MEM_read32(pMatch) == MEM_read32(pIn))) { pIn+=4; pMatch+=4; }
if ((pIn<(pInLimit-1)) && (MEM_read16(pMatch) == MEM_read16(pIn))) { pIn+=2; pMatch+=2; }
if ((pIn<pInLimit) && (*pMatch == *pIn)) pIn++;
return (size_t)(pIn - pStart);
}
/** ZSTD_count_2segments() :
* can count match length with `ip` & `match` in 2 different segments.
* convention : on reaching mEnd, match count continue starting from iStart
*/
static size_t ZSTD_count_2segments(const BYTE* ip, const BYTE* match, const BYTE* iEnd, const BYTE* mEnd, const BYTE* iStart)
{
const BYTE* const vEnd = MIN( ip + (mEnd - match), iEnd);
size_t const matchLength = ZSTD_count(ip, match, vEnd);
if (match + matchLength != mEnd) return matchLength;
return matchLength + ZSTD_count(ip+matchLength, iStart, iEnd);
}
/*-*************************************
* Hashes
***************************************/
static const U32 prime3bytes = 506832829U;
static U32 ZSTD_hash3(U32 u, U32 h) { return ((u << (32-24)) * prime3bytes) >> (32-h) ; }
MEM_STATIC size_t ZSTD_hash3Ptr(const void* ptr, U32 h) { return ZSTD_hash3(MEM_readLE32(ptr), h); } /* only in zstd_opt.h */
static const U32 prime4bytes = 2654435761U;
static U32 ZSTD_hash4(U32 u, U32 h) { return (u * prime4bytes) >> (32-h) ; }
static size_t ZSTD_hash4Ptr(const void* ptr, U32 h) { return ZSTD_hash4(MEM_read32(ptr), h); }
static const U64 prime5bytes = 889523592379ULL;
static size_t ZSTD_hash5(U64 u, U32 h) { return (size_t)(((u << (64-40)) * prime5bytes) >> (64-h)) ; }
static size_t ZSTD_hash5Ptr(const void* p, U32 h) { return ZSTD_hash5(MEM_readLE64(p), h); }
static const U64 prime6bytes = 227718039650203ULL;
static size_t ZSTD_hash6(U64 u, U32 h) { return (size_t)(((u << (64-48)) * prime6bytes) >> (64-h)) ; }
static size_t ZSTD_hash6Ptr(const void* p, U32 h) { return ZSTD_hash6(MEM_readLE64(p), h); }
static const U64 prime7bytes = 58295818150454627ULL;
static size_t ZSTD_hash7(U64 u, U32 h) { return (size_t)(((u << (64-56)) * prime7bytes) >> (64-h)) ; }
static size_t ZSTD_hash7Ptr(const void* p, U32 h) { return ZSTD_hash7(MEM_readLE64(p), h); }
static const U64 prime8bytes = 0xCF1BBCDCB7A56463ULL;
static size_t ZSTD_hash8(U64 u, U32 h) { return (size_t)(((u) * prime8bytes) >> (64-h)) ; }
static size_t ZSTD_hash8Ptr(const void* p, U32 h) { return ZSTD_hash8(MEM_readLE64(p), h); }
static size_t ZSTD_hashPtr(const void* p, U32 hBits, U32 mls)
{
switch(mls)
{
default:
case 4: return ZSTD_hash4Ptr(p, hBits);
case 5: return ZSTD_hash5Ptr(p, hBits);
case 6: return ZSTD_hash6Ptr(p, hBits);
case 7: return ZSTD_hash7Ptr(p, hBits);
case 8: return ZSTD_hash8Ptr(p, hBits);
}
}
/*-*************************************
* Fast Scan
***************************************/
static void ZSTD_fillHashTable (ZSTD_CCtx* zc, const void* end, const U32 mls)
{
U32* const hashTable = zc->hashTable;
U32 const hBits = zc->appliedParams.cParams.hashLog;
const BYTE* const base = zc->base;
const BYTE* ip = base + zc->nextToUpdate;
const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE;
const size_t fastHashFillStep = 3;
while(ip <= iend) {
hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip - base);
ip += fastHashFillStep;
}
}
FORCE_INLINE
void ZSTD_compressBlock_fast_generic(ZSTD_CCtx* cctx,
const void* src, size_t srcSize,
const U32 mls)
{
U32* const hashTable = cctx->hashTable;
U32 const hBits = cctx->appliedParams.cParams.hashLog;
seqStore_t* seqStorePtr = &(cctx->seqStore);
const BYTE* const base = cctx->base;
const BYTE* const istart = (const BYTE*)src;
const BYTE* ip = istart;
const BYTE* anchor = istart;
const U32 lowestIndex = cctx->dictLimit;
const BYTE* const lowest = base + lowestIndex;
const BYTE* const iend = istart + srcSize;
const BYTE* const ilimit = iend - HASH_READ_SIZE;
U32 offset_1=cctx->rep[0], offset_2=cctx->rep[1];
U32 offsetSaved = 0;
/* init */
ip += (ip==lowest);
{ U32 const maxRep = (U32)(ip-lowest);
if (offset_2 > maxRep) offsetSaved = offset_2, offset_2 = 0;
if (offset_1 > maxRep) offsetSaved = offset_1, offset_1 = 0;
}
/* Main Search Loop */
while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */
size_t mLength;
size_t const h = ZSTD_hashPtr(ip, hBits, mls);
U32 const current = (U32)(ip-base);
U32 const matchIndex = hashTable[h];
const BYTE* match = base + matchIndex;
hashTable[h] = current; /* update hash table */
if ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1))) {
mLength = ZSTD_count(ip+1+4, ip+1+4-offset_1, iend) + 4;
ip++;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, 0, mLength-MINMATCH);
} else {
U32 offset;
if ( (matchIndex <= lowestIndex) || (MEM_read32(match) != MEM_read32(ip)) ) {
ip += ((ip-anchor) >> g_searchStrength) + 1;
continue;
}
mLength = ZSTD_count(ip+4, match+4, iend) + 4;
offset = (U32)(ip-match);
while (((ip>anchor) & (match>lowest)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
offset_2 = offset_1;
offset_1 = offset;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
}
/* match found */
ip += mLength;
anchor = ip;
if (ip <= ilimit) {
/* Fill Table */
hashTable[ZSTD_hashPtr(base+current+2, hBits, mls)] = current+2; /* here because current+2 could be > iend-8 */
hashTable[ZSTD_hashPtr(ip-2, hBits, mls)] = (U32)(ip-2-base);
/* check immediate repcode */
while ( (ip <= ilimit)
&& ( (offset_2>0)
& (MEM_read32(ip) == MEM_read32(ip - offset_2)) )) {
/* store sequence */
size_t const rLength = ZSTD_count(ip+4, ip+4-offset_2, iend) + 4;
{ U32 const tmpOff = offset_2; offset_2 = offset_1; offset_1 = tmpOff; } /* swap offset_2 <=> offset_1 */
hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip-base);
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength-MINMATCH);
ip += rLength;
anchor = ip;
continue; /* faster when present ... (?) */
} } }
/* save reps for next block */
cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved;
cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved;
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
static void ZSTD_compressBlock_fast(ZSTD_CCtx* ctx,
const void* src, size_t srcSize)
{
const U32 mls = ctx->appliedParams.cParams.searchLength;
switch(mls)
{
default: /* includes case 3 */
case 4 :
ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 4); return;
case 5 :
ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 5); return;
case 6 :
ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 6); return;
case 7 :
ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 7); return;
}
}
static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize,
const U32 mls)
{
U32* hashTable = ctx->hashTable;
const U32 hBits = ctx->appliedParams.cParams.hashLog;
seqStore_t* seqStorePtr = &(ctx->seqStore);
const BYTE* const base = ctx->base;
const BYTE* const dictBase = ctx->dictBase;
const BYTE* const istart = (const BYTE*)src;
const BYTE* ip = istart;
const BYTE* anchor = istart;
const U32 lowestIndex = ctx->lowLimit;
const BYTE* const dictStart = dictBase + lowestIndex;
const U32 dictLimit = ctx->dictLimit;
const BYTE* const lowPrefixPtr = base + dictLimit;
const BYTE* const dictEnd = dictBase + dictLimit;
const BYTE* const iend = istart + srcSize;
const BYTE* const ilimit = iend - 8;
U32 offset_1=ctx->rep[0], offset_2=ctx->rep[1];
/* Search Loop */
while (ip < ilimit) { /* < instead of <=, because (ip+1) */
const size_t h = ZSTD_hashPtr(ip, hBits, mls);
const U32 matchIndex = hashTable[h];
const BYTE* matchBase = matchIndex < dictLimit ? dictBase : base;
const BYTE* match = matchBase + matchIndex;
const U32 current = (U32)(ip-base);
const U32 repIndex = current + 1 - offset_1; /* offset_1 expected <= current +1 */
const BYTE* repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* repMatch = repBase + repIndex;
size_t mLength;
hashTable[h] = current; /* update hash table */
if ( (((U32)((dictLimit-1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex))
&& (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
const BYTE* repMatchEnd = repIndex < dictLimit ? dictEnd : iend;
mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, lowPrefixPtr) + 4;
ip++;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, 0, mLength-MINMATCH);
} else {
if ( (matchIndex < lowestIndex) ||
(MEM_read32(match) != MEM_read32(ip)) ) {
ip += ((ip-anchor) >> g_searchStrength) + 1;
continue;
}
{ const BYTE* matchEnd = matchIndex < dictLimit ? dictEnd : iend;
const BYTE* lowMatchPtr = matchIndex < dictLimit ? dictStart : lowPrefixPtr;
U32 offset;
mLength = ZSTD_count_2segments(ip+4, match+4, iend, matchEnd, lowPrefixPtr) + 4;
while (((ip>anchor) & (match>lowMatchPtr)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
offset = current - matchIndex;
offset_2 = offset_1;
offset_1 = offset;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
} }
/* found a match : store it */
ip += mLength;
anchor = ip;
if (ip <= ilimit) {
/* Fill Table */
hashTable[ZSTD_hashPtr(base+current+2, hBits, mls)] = current+2;
hashTable[ZSTD_hashPtr(ip-2, hBits, mls)] = (U32)(ip-2-base);
/* check immediate repcode */
while (ip <= ilimit) {
U32 const current2 = (U32)(ip-base);
U32 const repIndex2 = current2 - offset_2;
const BYTE* repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2;
if ( (((U32)((dictLimit-1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */
&& (MEM_read32(repMatch2) == MEM_read32(ip)) ) {
const BYTE* const repEnd2 = repIndex2 < dictLimit ? dictEnd : iend;
size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, lowPrefixPtr) + 4;
U32 tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, repLength2-MINMATCH);
hashTable[ZSTD_hashPtr(ip, hBits, mls)] = current2;
ip += repLength2;
anchor = ip;
continue;
}
break;
} } }
/* save reps for next block */
ctx->repToConfirm[0] = offset_1; ctx->repToConfirm[1] = offset_2;
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx* ctx,
const void* src, size_t srcSize)
{
U32 const mls = ctx->appliedParams.cParams.searchLength;
switch(mls)
{
default: /* includes case 3 */
case 4 :
ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 4); return;
case 5 :
ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 5); return;
case 6 :
ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 6); return;
case 7 :
ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 7); return;
}
}
/*-*************************************
* Double Fast
***************************************/
static void ZSTD_fillDoubleHashTable (ZSTD_CCtx* cctx, const void* end, const U32 mls)
{
U32* const hashLarge = cctx->hashTable;
U32 const hBitsL = cctx->appliedParams.cParams.hashLog;
U32* const hashSmall = cctx->chainTable;
U32 const hBitsS = cctx->appliedParams.cParams.chainLog;
const BYTE* const base = cctx->base;
const BYTE* ip = base + cctx->nextToUpdate;
const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE;
const size_t fastHashFillStep = 3;
while(ip <= iend) {
hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip - base);
hashLarge[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip - base);
ip += fastHashFillStep;
}
}
FORCE_INLINE
void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx* cctx,
const void* src, size_t srcSize,
const U32 mls)
{
U32* const hashLong = cctx->hashTable;
const U32 hBitsL = cctx->appliedParams.cParams.hashLog;
U32* const hashSmall = cctx->chainTable;
const U32 hBitsS = cctx->appliedParams.cParams.chainLog;
seqStore_t* seqStorePtr = &(cctx->seqStore);
const BYTE* const base = cctx->base;
const BYTE* const istart = (const BYTE*)src;
const BYTE* ip = istart;
const BYTE* anchor = istart;
const U32 lowestIndex = cctx->dictLimit;
const BYTE* const lowest = base + lowestIndex;
const BYTE* const iend = istart + srcSize;
const BYTE* const ilimit = iend - HASH_READ_SIZE;
U32 offset_1=cctx->rep[0], offset_2=cctx->rep[1];
U32 offsetSaved = 0;
/* init */
ip += (ip==lowest);
{ U32 const maxRep = (U32)(ip-lowest);
if (offset_2 > maxRep) offsetSaved = offset_2, offset_2 = 0;
if (offset_1 > maxRep) offsetSaved = offset_1, offset_1 = 0;
}
/* Main Search Loop */
while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */
size_t mLength;
size_t const h2 = ZSTD_hashPtr(ip, hBitsL, 8);
size_t const h = ZSTD_hashPtr(ip, hBitsS, mls);
U32 const current = (U32)(ip-base);
U32 const matchIndexL = hashLong[h2];
U32 const matchIndexS = hashSmall[h];
const BYTE* matchLong = base + matchIndexL;
const BYTE* match = base + matchIndexS;
hashLong[h2] = hashSmall[h] = current; /* update hash tables */
assert(offset_1 <= current); /* supposed guaranteed by construction */
if ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1))) {
/* favor repcode */
mLength = ZSTD_count(ip+1+4, ip+1+4-offset_1, iend) + 4;
ip++;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, 0, mLength-MINMATCH);
} else {
U32 offset;
if ( (matchIndexL > lowestIndex) && (MEM_read64(matchLong) == MEM_read64(ip)) ) {
mLength = ZSTD_count(ip+8, matchLong+8, iend) + 8;
offset = (U32)(ip-matchLong);
while (((ip>anchor) & (matchLong>lowest)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */
} else if ( (matchIndexS > lowestIndex) && (MEM_read32(match) == MEM_read32(ip)) ) {
size_t const hl3 = ZSTD_hashPtr(ip+1, hBitsL, 8);
U32 const matchIndexL3 = hashLong[hl3];
const BYTE* matchL3 = base + matchIndexL3;
hashLong[hl3] = current + 1;
if ( (matchIndexL3 > lowestIndex) && (MEM_read64(matchL3) == MEM_read64(ip+1)) ) {
mLength = ZSTD_count(ip+9, matchL3+8, iend) + 8;
ip++;
offset = (U32)(ip-matchL3);
while (((ip>anchor) & (matchL3>lowest)) && (ip[-1] == matchL3[-1])) { ip--; matchL3--; mLength++; } /* catch up */
} else {
mLength = ZSTD_count(ip+4, match+4, iend) + 4;
offset = (U32)(ip-match);
while (((ip>anchor) & (match>lowest)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
}
} else {
ip += ((ip-anchor) >> g_searchStrength) + 1;
continue;
}
offset_2 = offset_1;
offset_1 = offset;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
}
/* match found */
ip += mLength;
anchor = ip;
if (ip <= ilimit) {
/* Fill Table */
hashLong[ZSTD_hashPtr(base+current+2, hBitsL, 8)] =
hashSmall[ZSTD_hashPtr(base+current+2, hBitsS, mls)] = current+2; /* here because current+2 could be > iend-8 */
hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] =
hashSmall[ZSTD_hashPtr(ip-2, hBitsS, mls)] = (U32)(ip-2-base);
/* check immediate repcode */
while ( (ip <= ilimit)
&& ( (offset_2>0)
& (MEM_read32(ip) == MEM_read32(ip - offset_2)) )) {
/* store sequence */
size_t const rLength = ZSTD_count(ip+4, ip+4-offset_2, iend) + 4;
{ U32 const tmpOff = offset_2; offset_2 = offset_1; offset_1 = tmpOff; } /* swap offset_2 <=> offset_1 */
hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip-base);
hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip-base);
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength-MINMATCH);
ip += rLength;
anchor = ip;
continue; /* faster when present ... (?) */
} } }
/* save reps for next block */
cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved;
cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved;
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
static void ZSTD_compressBlock_doubleFast(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
const U32 mls = ctx->appliedParams.cParams.searchLength;
switch(mls)
{
default: /* includes case 3 */
case 4 :
ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 4); return;
case 5 :
ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 5); return;
case 6 :
ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 6); return;
case 7 :
ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 7); return;
}
}
static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize,
const U32 mls)
{
U32* const hashLong = ctx->hashTable;
U32 const hBitsL = ctx->appliedParams.cParams.hashLog;
U32* const hashSmall = ctx->chainTable;
U32 const hBitsS = ctx->appliedParams.cParams.chainLog;
seqStore_t* seqStorePtr = &(ctx->seqStore);
const BYTE* const base = ctx->base;
const BYTE* const dictBase = ctx->dictBase;
const BYTE* const istart = (const BYTE*)src;
const BYTE* ip = istart;
const BYTE* anchor = istart;
const U32 lowestIndex = ctx->lowLimit;
const BYTE* const dictStart = dictBase + lowestIndex;
const U32 dictLimit = ctx->dictLimit;
const BYTE* const lowPrefixPtr = base + dictLimit;
const BYTE* const dictEnd = dictBase + dictLimit;
const BYTE* const iend = istart + srcSize;
const BYTE* const ilimit = iend - 8;
U32 offset_1=ctx->rep[0], offset_2=ctx->rep[1];
/* Search Loop */
while (ip < ilimit) { /* < instead of <=, because (ip+1) */
const size_t hSmall = ZSTD_hashPtr(ip, hBitsS, mls);
const U32 matchIndex = hashSmall[hSmall];
const BYTE* matchBase = matchIndex < dictLimit ? dictBase : base;
const BYTE* match = matchBase + matchIndex;
const size_t hLong = ZSTD_hashPtr(ip, hBitsL, 8);
const U32 matchLongIndex = hashLong[hLong];
const BYTE* matchLongBase = matchLongIndex < dictLimit ? dictBase : base;
const BYTE* matchLong = matchLongBase + matchLongIndex;
const U32 current = (U32)(ip-base);
const U32 repIndex = current + 1 - offset_1; /* offset_1 expected <= current +1 */
const BYTE* repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* repMatch = repBase + repIndex;
size_t mLength;
hashSmall[hSmall] = hashLong[hLong] = current; /* update hash table */
if ( (((U32)((dictLimit-1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex))
&& (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
const BYTE* repMatchEnd = repIndex < dictLimit ? dictEnd : iend;
mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, lowPrefixPtr) + 4;
ip++;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, 0, mLength-MINMATCH);
} else {
if ((matchLongIndex > lowestIndex) && (MEM_read64(matchLong) == MEM_read64(ip))) {
const BYTE* matchEnd = matchLongIndex < dictLimit ? dictEnd : iend;
const BYTE* lowMatchPtr = matchLongIndex < dictLimit ? dictStart : lowPrefixPtr;
U32 offset;
mLength = ZSTD_count_2segments(ip+8, matchLong+8, iend, matchEnd, lowPrefixPtr) + 8;
offset = current - matchLongIndex;
while (((ip>anchor) & (matchLong>lowMatchPtr)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */
offset_2 = offset_1;
offset_1 = offset;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
} else if ((matchIndex > lowestIndex) && (MEM_read32(match) == MEM_read32(ip))) {
size_t const h3 = ZSTD_hashPtr(ip+1, hBitsL, 8);
U32 const matchIndex3 = hashLong[h3];
const BYTE* const match3Base = matchIndex3 < dictLimit ? dictBase : base;
const BYTE* match3 = match3Base + matchIndex3;
U32 offset;
hashLong[h3] = current + 1;
if ( (matchIndex3 > lowestIndex) && (MEM_read64(match3) == MEM_read64(ip+1)) ) {
const BYTE* matchEnd = matchIndex3 < dictLimit ? dictEnd : iend;
const BYTE* lowMatchPtr = matchIndex3 < dictLimit ? dictStart : lowPrefixPtr;
mLength = ZSTD_count_2segments(ip+9, match3+8, iend, matchEnd, lowPrefixPtr) + 8;
ip++;
offset = current+1 - matchIndex3;
while (((ip>anchor) & (match3>lowMatchPtr)) && (ip[-1] == match3[-1])) { ip--; match3--; mLength++; } /* catch up */
} else {
const BYTE* matchEnd = matchIndex < dictLimit ? dictEnd : iend;
const BYTE* lowMatchPtr = matchIndex < dictLimit ? dictStart : lowPrefixPtr;
mLength = ZSTD_count_2segments(ip+4, match+4, iend, matchEnd, lowPrefixPtr) + 4;
offset = current - matchIndex;
while (((ip>anchor) & (match>lowMatchPtr)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
}
offset_2 = offset_1;
offset_1 = offset;
ZSTD_storeSeq(seqStorePtr, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
} else {
ip += ((ip-anchor) >> g_searchStrength) + 1;
continue;
} }
/* found a match : store it */
ip += mLength;
anchor = ip;
if (ip <= ilimit) {
/* Fill Table */
hashSmall[ZSTD_hashPtr(base+current+2, hBitsS, mls)] = current+2;
hashLong[ZSTD_hashPtr(base+current+2, hBitsL, 8)] = current+2;
hashSmall[ZSTD_hashPtr(ip-2, hBitsS, mls)] = (U32)(ip-2-base);
hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base);
/* check immediate repcode */
while (ip <= ilimit) {
U32 const current2 = (U32)(ip-base);
U32 const repIndex2 = current2 - offset_2;
const BYTE* repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2;
if ( (((U32)((dictLimit-1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */
&& (MEM_read32(repMatch2) == MEM_read32(ip)) ) {
const BYTE* const repEnd2 = repIndex2 < dictLimit ? dictEnd : iend;
size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, lowPrefixPtr) + 4;
U32 tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, repLength2-MINMATCH);
hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = current2;
hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = current2;
ip += repLength2;
anchor = ip;
continue;
}
break;
} } }
/* save reps for next block */
ctx->repToConfirm[0] = offset_1; ctx->repToConfirm[1] = offset_2;
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
static void ZSTD_compressBlock_doubleFast_extDict(ZSTD_CCtx* ctx,
const void* src, size_t srcSize)
{
U32 const mls = ctx->appliedParams.cParams.searchLength;
switch(mls)
{
default: /* includes case 3 */
case 4 :
ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 4); return;
case 5 :
ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 5); return;
case 6 :
ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 6); return;
case 7 :
ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 7); return;
}
}
/*-*************************************
* Binary Tree search
***************************************/
/** ZSTD_insertBt1() : add one or multiple positions to tree.
* ip : assumed <= iend-8 .
* @return : nb of positions added */
static U32 ZSTD_insertBt1(ZSTD_CCtx* zc, const BYTE* const ip, const U32 mls, const BYTE* const iend, U32 nbCompares,
U32 extDict)
{
U32* const hashTable = zc->hashTable;
U32 const hashLog = zc->appliedParams.cParams.hashLog;
size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
U32* const bt = zc->chainTable;
U32 const btLog = zc->appliedParams.cParams.chainLog - 1;
U32 const btMask = (1 << btLog) - 1;
U32 matchIndex = hashTable[h];
size_t commonLengthSmaller=0, commonLengthLarger=0;
const BYTE* const base = zc->base;
const BYTE* const dictBase = zc->dictBase;
const U32 dictLimit = zc->dictLimit;
const BYTE* const dictEnd = dictBase + dictLimit;
const BYTE* const prefixStart = base + dictLimit;
const BYTE* match;
const U32 current = (U32)(ip-base);
const U32 btLow = btMask >= current ? 0 : current - btMask;
U32* smallerPtr = bt + 2*(current&btMask);
U32* largerPtr = smallerPtr + 1;
U32 dummy32; /* to be nullified at the end */
U32 const windowLow = zc->lowLimit;
U32 matchEndIdx = current+8;
size_t bestLength = 8;
#ifdef ZSTD_C_PREDICT
U32 predictedSmall = *(bt + 2*((current-1)&btMask) + 0);
U32 predictedLarge = *(bt + 2*((current-1)&btMask) + 1);
predictedSmall += (predictedSmall>0);
predictedLarge += (predictedLarge>0);
#endif /* ZSTD_C_PREDICT */
hashTable[h] = current; /* Update Hash Table */
while (nbCompares-- && (matchIndex > windowLow)) {
U32* const nextPtr = bt + 2*(matchIndex & btMask);
size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
#ifdef ZSTD_C_PREDICT /* note : can create issues when hlog small <= 11 */
const U32* predictPtr = bt + 2*((matchIndex-1) & btMask); /* written this way, as bt is a roll buffer */
if (matchIndex == predictedSmall) {
/* no need to check length, result known */
*smallerPtr = matchIndex;
if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop the search */
smallerPtr = nextPtr+1; /* new "smaller" => larger of match */
matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */
predictedSmall = predictPtr[1] + (predictPtr[1]>0);
continue;
}
if (matchIndex == predictedLarge) {
*largerPtr = matchIndex;
if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */
largerPtr = nextPtr;
matchIndex = nextPtr[0];
predictedLarge = predictPtr[0] + (predictPtr[0]>0);
continue;
}
#endif
if ((!extDict) || (matchIndex+matchLength >= dictLimit)) {
match = base + matchIndex;
if (match[matchLength] == ip[matchLength])
matchLength += ZSTD_count(ip+matchLength+1, match+matchLength+1, iend) +1;
} else {
match = dictBase + matchIndex;
matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iend, dictEnd, prefixStart);
if (matchIndex+matchLength >= dictLimit)
match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
}
if (matchLength > bestLength) {
bestLength = matchLength;
if (matchLength > matchEndIdx - matchIndex)
matchEndIdx = matchIndex + (U32)matchLength;
}
if (ip+matchLength == iend) /* equal : no way to know if inf or sup */
break; /* drop , to guarantee consistency ; miss a bit of compression, but other solutions can corrupt the tree */
if (match[matchLength] < ip[matchLength]) { /* necessarily within correct buffer */
/* match is smaller than current */
*smallerPtr = matchIndex; /* update smaller idx */
commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop the search */
smallerPtr = nextPtr+1; /* new "smaller" => larger of match */
matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */
} else {
/* match is larger than current */
*largerPtr = matchIndex;
commonLengthLarger = matchLength;
if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */
largerPtr = nextPtr;
matchIndex = nextPtr[0];
} }
*smallerPtr = *largerPtr = 0;
if (bestLength > 384) return MIN(192, (U32)(bestLength - 384)); /* speed optimization */
if (matchEndIdx > current + 8) return matchEndIdx - current - 8;
return 1;
}
static size_t ZSTD_insertBtAndFindBestMatch (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iend,
size_t* offsetPtr,
U32 nbCompares, const U32 mls,
U32 extDict)
{
U32* const hashTable = zc->hashTable;
U32 const hashLog = zc->appliedParams.cParams.hashLog;
size_t const h = ZSTD_hashPtr(ip, hashLog, mls);
U32* const bt = zc->chainTable;
U32 const btLog = zc->appliedParams.cParams.chainLog - 1;
U32 const btMask = (1 << btLog) - 1;
U32 matchIndex = hashTable[h];
size_t commonLengthSmaller=0, commonLengthLarger=0;
const BYTE* const base = zc->base;
const BYTE* const dictBase = zc->dictBase;
const U32 dictLimit = zc->dictLimit;
const BYTE* const dictEnd = dictBase + dictLimit;
const BYTE* const prefixStart = base + dictLimit;
const U32 current = (U32)(ip-base);
const U32 btLow = btMask >= current ? 0 : current - btMask;
const U32 windowLow = zc->lowLimit;
U32* smallerPtr = bt + 2*(current&btMask);
U32* largerPtr = bt + 2*(current&btMask) + 1;
U32 matchEndIdx = current+8;
U32 dummy32; /* to be nullified at the end */
size_t bestLength = 0;
hashTable[h] = current; /* Update Hash Table */
while (nbCompares-- && (matchIndex > windowLow)) {
U32* const nextPtr = bt + 2*(matchIndex & btMask);
size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
const BYTE* match;
if ((!extDict) || (matchIndex+matchLength >= dictLimit)) {
match = base + matchIndex;
if (match[matchLength] == ip[matchLength])
matchLength += ZSTD_count(ip+matchLength+1, match+matchLength+1, iend) +1;
} else {
match = dictBase + matchIndex;
matchLength += ZSTD_count_2segments(ip+matchLength, match+matchLength, iend, dictEnd, prefixStart);
if (matchIndex+matchLength >= dictLimit)
match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
}
if (matchLength > bestLength) {
if (matchLength > matchEndIdx - matchIndex)
matchEndIdx = matchIndex + (U32)matchLength;
if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(current-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) )
bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + current - matchIndex;
if (ip+matchLength == iend) /* equal : no way to know if inf or sup */
break; /* drop, to guarantee consistency (miss a little bit of compression) */
}
if (match[matchLength] < ip[matchLength]) {
/* match is smaller than current */
*smallerPtr = matchIndex; /* update smaller idx */
commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
if (matchIndex <= btLow) { smallerPtr=&dummy32; break; } /* beyond tree size, stop the search */
smallerPtr = nextPtr+1; /* new "smaller" => larger of match */
matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to current) */
} else {
/* match is larger than current */
*largerPtr = matchIndex;
commonLengthLarger = matchLength;
if (matchIndex <= btLow) { largerPtr=&dummy32; break; } /* beyond tree size, stop the search */
largerPtr = nextPtr;
matchIndex = nextPtr[0];
} }
*smallerPtr = *largerPtr = 0;
zc->nextToUpdate = (matchEndIdx > current + 8) ? matchEndIdx - 8 : current+1;
return bestLength;
}
static void ZSTD_updateTree(ZSTD_CCtx* zc, const BYTE* const ip, const BYTE* const iend, const U32 nbCompares, const U32 mls)
{
const BYTE* const base = zc->base;
const U32 target = (U32)(ip - base);
U32 idx = zc->nextToUpdate;
while(idx < target)
idx += ZSTD_insertBt1(zc, base+idx, mls, iend, nbCompares, 0);
}
/** ZSTD_BtFindBestMatch() : Tree updater, providing best match */
static size_t ZSTD_BtFindBestMatch (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iLimit,
size_t* offsetPtr,
const U32 maxNbAttempts, const U32 mls)
{
if (ip < zc->base + zc->nextToUpdate) return 0; /* skipped area */
ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls);
return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 0);
}
static size_t ZSTD_BtFindBestMatch_selectMLS (
ZSTD_CCtx* zc, /* Index table will be updated */
const BYTE* ip, const BYTE* const iLimit,
size_t* offsetPtr,
const U32 maxNbAttempts, const U32 matchLengthSearch)
{
switch(matchLengthSearch)
{
default : /* includes case 3 */
case 4 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4);
case 5 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5);
case 7 :
case 6 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6);
}
}
static void ZSTD_updateTree_extDict(ZSTD_CCtx* zc, const BYTE* const ip, const BYTE* const iend, const U32 nbCompares, const U32 mls)
{
const BYTE* const base = zc->base;
const U32 target = (U32)(ip - base);
U32 idx = zc->nextToUpdate;
while (idx < target) idx += ZSTD_insertBt1(zc, base+idx, mls, iend, nbCompares, 1);
}
/** Tree updater, providing best match */
static size_t ZSTD_BtFindBestMatch_extDict (
ZSTD_CCtx* zc,
const BYTE* const ip, const BYTE* const iLimit,
size_t* offsetPtr,
const U32 maxNbAttempts, const U32 mls)
{
if (ip < zc->base + zc->nextToUpdate) return 0; /* skipped area */
ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls);
return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 1);
}
static size_t ZSTD_BtFindBestMatch_selectMLS_extDict (
ZSTD_CCtx* zc, /* Index table will be updated */
const BYTE* ip, const BYTE* const iLimit,
size_t* offsetPtr,
const U32 maxNbAttempts, const U32 matchLengthSearch)
{
switch(matchLengthSearch)
{
default : /* includes case 3 */
case 4 : return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4);
case 5 : return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5);
case 7 :
case 6 : return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6);
}
}
/* *********************************
* Hash Chain
***********************************/
#define NEXT_IN_CHAIN(d, mask) chainTable[(d) & mask]
/* Update chains up to ip (excluded)
Assumption : always within prefix (i.e. not within extDict) */
FORCE_INLINE
U32 ZSTD_insertAndFindFirstIndex (ZSTD_CCtx* zc, const BYTE* ip, U32 mls)
{
U32* const hashTable = zc->hashTable;
const U32 hashLog = zc->appliedParams.cParams.hashLog;
U32* const chainTable = zc->chainTable;
const U32 chainMask = (1 << zc->appliedParams.cParams.chainLog) - 1;
const BYTE* const base = zc->base;
const U32 target = (U32)(ip - base);
U32 idx = zc->nextToUpdate;
while(idx < target) { /* catch up */
size_t const h = ZSTD_hashPtr(base+idx, hashLog, mls);
NEXT_IN_CHAIN(idx, chainMask) = hashTable[h];
hashTable[h] = idx;
idx++;
}
zc->nextToUpdate = target;
return hashTable[ZSTD_hashPtr(ip, hashLog, mls)];
}
/* inlining is important to hardwire a hot branch (template emulation) */
FORCE_INLINE
size_t ZSTD_HcFindBestMatch_generic (
ZSTD_CCtx* zc, /* Index table will be updated */
const BYTE* const ip, const BYTE* const iLimit,
size_t* offsetPtr,
const U32 maxNbAttempts, const U32 mls, const U32 extDict)
{
U32* const chainTable = zc->chainTable;
const U32 chainSize = (1 << zc->appliedParams.cParams.chainLog);
const U32 chainMask = chainSize-1;
const BYTE* const base = zc->base;
const BYTE* const dictBase = zc->dictBase;
const U32 dictLimit = zc->dictLimit;
const BYTE* const prefixStart = base + dictLimit;
const BYTE* const dictEnd = dictBase + dictLimit;
const U32 lowLimit = zc->lowLimit;
const U32 current = (U32)(ip-base);
const U32 minChain = current > chainSize ? current - chainSize : 0;
int nbAttempts=maxNbAttempts;
size_t ml=4-1;
/* HC4 match finder */
U32 matchIndex = ZSTD_insertAndFindFirstIndex (zc, ip, mls);
for ( ; (matchIndex>lowLimit) & (nbAttempts>0) ; nbAttempts--) {
const BYTE* match;
size_t currentMl=0;
if ((!extDict) || matchIndex >= dictLimit) {
match = base + matchIndex;
if (match[ml] == ip[ml]) /* potentially better */
currentMl = ZSTD_count(ip, match, iLimit);
} else {
match = dictBase + matchIndex;
if (MEM_read32(match) == MEM_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */
currentMl = ZSTD_count_2segments(ip+4, match+4, iLimit, dictEnd, prefixStart) + 4;
}
/* save best solution */
if (currentMl > ml) {
ml = currentMl;
*offsetPtr = current - matchIndex + ZSTD_REP_MOVE;
if (ip+currentMl == iLimit) break; /* best possible, avoids read overflow on next attempt */
}
if (matchIndex <= minChain) break;
matchIndex = NEXT_IN_CHAIN(matchIndex, chainMask);
}
return ml;
}
FORCE_INLINE size_t ZSTD_HcFindBestMatch_selectMLS (
ZSTD_CCtx* zc,
const BYTE* ip, const BYTE* const iLimit,
size_t* offsetPtr,
const U32 maxNbAttempts, const U32 matchLengthSearch)
{
switch(matchLengthSearch)
{
default : /* includes case 3 */
case 4 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 0);
case 5 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 0);
case 7 :
case 6 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 0);
}
}
FORCE_INLINE size_t ZSTD_HcFindBestMatch_extDict_selectMLS (
ZSTD_CCtx* zc,
const BYTE* ip, const BYTE* const iLimit,
size_t* offsetPtr,
const U32 maxNbAttempts, const U32 matchLengthSearch)
{
switch(matchLengthSearch)
{
default : /* includes case 3 */
case 4 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 1);
case 5 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 1);
case 7 :
case 6 : return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 1);
}
}
/* *******************************
* Common parser - lazy strategy
*********************************/
FORCE_INLINE
void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize,
const U32 searchMethod, const U32 depth)
{
seqStore_t* seqStorePtr = &(ctx->seqStore);
const BYTE* const istart = (const BYTE*)src;
const BYTE* ip = istart;
const BYTE* anchor = istart;
const BYTE* const iend = istart + srcSize;
const BYTE* const ilimit = iend - 8;
const BYTE* const base = ctx->base + ctx->dictLimit;
U32 const maxSearches = 1 << ctx->appliedParams.cParams.searchLog;
U32 const mls = ctx->appliedParams.cParams.searchLength;
typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
size_t* offsetPtr,
U32 maxNbAttempts, U32 matchLengthSearch);
searchMax_f const searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS;
U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1], savedOffset=0;
/* init */
ip += (ip==base);
ctx->nextToUpdate3 = ctx->nextToUpdate;
{ U32 const maxRep = (U32)(ip-base);
if (offset_2 > maxRep) savedOffset = offset_2, offset_2 = 0;
if (offset_1 > maxRep) savedOffset = offset_1, offset_1 = 0;
}
/* Match Loop */
while (ip < ilimit) {
size_t matchLength=0;
size_t offset=0;
const BYTE* start=ip+1;
/* check repCode */
if ((offset_1>0) & (MEM_read32(ip+1) == MEM_read32(ip+1 - offset_1))) {
/* repcode : we take it */
matchLength = ZSTD_count(ip+1+4, ip+1+4-offset_1, iend) + 4;
if (depth==0) goto _storeSequence;
}
/* first search (depth 0) */
{ size_t offsetFound = 99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offsetFound, maxSearches, mls);
if (ml2 > matchLength)
matchLength = ml2, start = ip, offset=offsetFound;
}
if (matchLength < 4) {
ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
continue;
}
/* let's try to find a better solution */
if (depth>=1)
while (ip<ilimit) {
ip ++;
if ((offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) {
size_t const mlRep = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4;
int const gain2 = (int)(mlRep * 3);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
if ((mlRep >= 4) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
}
{ size_t offset2=99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 4);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue; /* search a better one */
} }
/* let's find an even better one */
if ((depth==2) && (ip<ilimit)) {
ip ++;
if ((offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) {
size_t const ml2 = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4;
int const gain2 = (int)(ml2 * 4);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
if ((ml2 >= 4) && (gain2 > gain1))
matchLength = ml2, offset = 0, start = ip;
}
{ size_t offset2=99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 7);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue;
} } }
break; /* nothing found : store previous solution */
}
/* NOTE:
* start[-offset+ZSTD_REP_MOVE-1] is undefined behavior.
* (-offset+ZSTD_REP_MOVE-1) is unsigned, and is added to start, which
* overflows the pointer, which is undefined behavior.
*/
/* catch up */
if (offset) {
while ( (start > anchor)
&& (start > base+offset-ZSTD_REP_MOVE)
&& (start[-1] == (start-offset+ZSTD_REP_MOVE)[-1]) ) /* only search for offset within prefix */
{ start--; matchLength++; }
offset_2 = offset_1; offset_1 = (U32)(offset - ZSTD_REP_MOVE);
}
/* store sequence */
_storeSequence:
{ size_t const litLength = start - anchor;
ZSTD_storeSeq(seqStorePtr, litLength, anchor, (U32)offset, matchLength-MINMATCH);
anchor = ip = start + matchLength;
}
/* check immediate repcode */
while ( (ip <= ilimit)
&& ((offset_2>0)
& (MEM_read32(ip) == MEM_read32(ip - offset_2)) )) {
/* store sequence */
matchLength = ZSTD_count(ip+4, ip+4-offset_2, iend) + 4;
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap repcodes */
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength-MINMATCH);
ip += matchLength;
anchor = ip;
continue; /* faster when present ... (?) */
} }
/* Save reps for next block */
ctx->repToConfirm[0] = offset_1 ? offset_1 : savedOffset;
ctx->repToConfirm[1] = offset_2 ? offset_2 : savedOffset;
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
static void ZSTD_compressBlock_btlazy2(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 1, 2);
}
static void ZSTD_compressBlock_lazy2(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 2);
}
static void ZSTD_compressBlock_lazy(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 1);
}
static void ZSTD_compressBlock_greedy(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 0);
}
FORCE_INLINE
void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
const void* src, size_t srcSize,
const U32 searchMethod, const U32 depth)
{
seqStore_t* seqStorePtr = &(ctx->seqStore);
const BYTE* const istart = (const BYTE*)src;
const BYTE* ip = istart;
const BYTE* anchor = istart;
const BYTE* const iend = istart + srcSize;
const BYTE* const ilimit = iend - 8;
const BYTE* const base = ctx->base;
const U32 dictLimit = ctx->dictLimit;
const U32 lowestIndex = ctx->lowLimit;
const BYTE* const prefixStart = base + dictLimit;
const BYTE* const dictBase = ctx->dictBase;
const BYTE* const dictEnd = dictBase + dictLimit;
const BYTE* const dictStart = dictBase + ctx->lowLimit;
const U32 maxSearches = 1 << ctx->appliedParams.cParams.searchLog;
const U32 mls = ctx->appliedParams.cParams.searchLength;
typedef size_t (*searchMax_f)(ZSTD_CCtx* zc, const BYTE* ip, const BYTE* iLimit,
size_t* offsetPtr,
U32 maxNbAttempts, U32 matchLengthSearch);
searchMax_f searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS_extDict : ZSTD_HcFindBestMatch_extDict_selectMLS;
U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1];
/* init */
ctx->nextToUpdate3 = ctx->nextToUpdate;
ip += (ip == prefixStart);
/* Match Loop */
while (ip < ilimit) {
size_t matchLength=0;
size_t offset=0;
const BYTE* start=ip+1;
U32 current = (U32)(ip-base);
/* check repCode */
{ const U32 repIndex = (U32)(current+1 - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip+1) == MEM_read32(repMatch)) {
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
matchLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repEnd, prefixStart) + 4;
if (depth==0) goto _storeSequence;
} }
/* first search (depth 0) */
{ size_t offsetFound = 99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offsetFound, maxSearches, mls);
if (ml2 > matchLength)
matchLength = ml2, start = ip, offset=offsetFound;
}
if (matchLength < 4) {
ip += ((ip-anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */
continue;
}
/* let's try to find a better solution */
if (depth>=1)
while (ip<ilimit) {
ip ++;
current++;
/* check repCode */
if (offset) {
const U32 repIndex = (U32)(current - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip) == MEM_read32(repMatch)) {
/* repcode detected */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
size_t const repLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4;
int const gain2 = (int)(repLength * 3);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
if ((repLength >= 4) && (gain2 > gain1))
matchLength = repLength, offset = 0, start = ip;
} }
/* search match, depth 1 */
{ size_t offset2=99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 4);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue; /* search a better one */
} }
/* let's find an even better one */
if ((depth==2) && (ip<ilimit)) {
ip ++;
current++;
/* check repCode */
if (offset) {
const U32 repIndex = (U32)(current - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip) == MEM_read32(repMatch)) {
/* repcode detected */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
size_t const repLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4;
int const gain2 = (int)(repLength * 4);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
if ((repLength >= 4) && (gain2 > gain1))
matchLength = repLength, offset = 0, start = ip;
} }
/* search match, depth 2 */
{ size_t offset2=99999999;
size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 7);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
continue;
} } }
break; /* nothing found : store previous solution */
}
/* catch up */
if (offset) {
U32 const matchIndex = (U32)((start-base) - (offset - ZSTD_REP_MOVE));
const BYTE* match = (matchIndex < dictLimit) ? dictBase + matchIndex : base + matchIndex;
const BYTE* const mStart = (matchIndex < dictLimit) ? dictStart : prefixStart;
while ((start>anchor) && (match>mStart) && (start[-1] == match[-1])) { start--; match--; matchLength++; } /* catch up */
offset_2 = offset_1; offset_1 = (U32)(offset - ZSTD_REP_MOVE);
}
/* store sequence */
_storeSequence:
{ size_t const litLength = start - anchor;
ZSTD_storeSeq(seqStorePtr, litLength, anchor, (U32)offset, matchLength-MINMATCH);
anchor = ip = start + matchLength;
}
/* check immediate repcode */
while (ip <= ilimit) {
const U32 repIndex = (U32)((ip-base) - offset_2);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
if (MEM_read32(ip) == MEM_read32(repMatch)) {
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
matchLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4;
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap offset history */
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength-MINMATCH);
ip += matchLength;
anchor = ip;
continue; /* faster when present ... (?) */
}
break;
} }
/* Save reps for next block */
ctx->repToConfirm[0] = offset_1; ctx->repToConfirm[1] = offset_2;
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
}
void ZSTD_compressBlock_greedy_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 0);
}
static void ZSTD_compressBlock_lazy_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 1);
}
static void ZSTD_compressBlock_lazy2_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 2);
}
static void ZSTD_compressBlock_btlazy2_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 1, 2);
}
/* The optimal parser */
#include "zstd_opt.h"
static void ZSTD_compressBlock_btopt(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
#ifdef ZSTD_OPT_H_91842398743
ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 0);
#else
(void)ctx; (void)src; (void)srcSize;
return;
#endif
}
static void ZSTD_compressBlock_btultra(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
#ifdef ZSTD_OPT_H_91842398743
ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 1);
#else
(void)ctx; (void)src; (void)srcSize;
return;
#endif
}
static void ZSTD_compressBlock_btopt_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
#ifdef ZSTD_OPT_H_91842398743
ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 0);
#else
(void)ctx; (void)src; (void)srcSize;
return;
#endif
}
static void ZSTD_compressBlock_btultra_extDict(ZSTD_CCtx* ctx, const void* src, size_t srcSize)
{
#ifdef ZSTD_OPT_H_91842398743
ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 1);
#else
(void)ctx; (void)src; (void)srcSize;
return;
#endif
}
/* ZSTD_selectBlockCompressor() :
* assumption : strat is a valid strategy */
typedef void (*ZSTD_blockCompressor) (ZSTD_CCtx* ctx, const void* src, size_t srcSize);
static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict)
{
static const ZSTD_blockCompressor blockCompressor[2][(unsigned)ZSTD_btultra+1] = {
{ ZSTD_compressBlock_fast /* default for 0 */,
ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy,
ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2, ZSTD_compressBlock_btlazy2,
ZSTD_compressBlock_btopt, ZSTD_compressBlock_btultra },
{ ZSTD_compressBlock_fast_extDict /* default for 0 */,
ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict,
ZSTD_compressBlock_lazy_extDict,ZSTD_compressBlock_lazy2_extDict, ZSTD_compressBlock_btlazy2_extDict,
ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btultra_extDict }
};
ZSTD_STATIC_ASSERT((unsigned)ZSTD_fast == 1);
assert((U32)strat >= (U32)ZSTD_fast);
assert((U32)strat <= (U32)ZSTD_btultra);
return blockCompressor[extDict!=0][(U32)strat];
}
static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->appliedParams.cParams.strategy, zc->lowLimit < zc->dictLimit);
const BYTE* const base = zc->base;
const BYTE* const istart = (const BYTE*)src;
const U32 current = (U32)(istart-base);
if (srcSize < MIN_CBLOCK_SIZE+ZSTD_blockHeaderSize+1) return 0; /* don't even attempt compression below a certain srcSize */
ZSTD_resetSeqStore(&(zc->seqStore));
if (current > zc->nextToUpdate + 384)
zc->nextToUpdate = current - MIN(192, (U32)(current - zc->nextToUpdate - 384)); /* limited update after finding a very long match */
blockCompressor(zc, src, srcSize);
return ZSTD_compressSequences(zc, dst, dstCapacity, srcSize);
}
/*! ZSTD_compress_frameChunk() :
* Compress a chunk of data into one or multiple blocks.
* All blocks will be terminated, all input will be consumed.
* Function will issue an error if there is not enough `dstCapacity` to hold the compressed content.
* Frame is supposed already started (header already produced)
* @return : compressed size, or an error code
*/
static size_t ZSTD_compress_frameChunk (ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
U32 lastFrameChunk)
{
size_t blockSize = cctx->blockSize;
size_t remaining = srcSize;
const BYTE* ip = (const BYTE*)src;
BYTE* const ostart = (BYTE*)dst;
BYTE* op = ostart;
U32 const maxDist = 1 << cctx->appliedParams.cParams.windowLog;
if (cctx->appliedParams.fParams.checksumFlag && srcSize)
XXH64_update(&cctx->xxhState, src, srcSize);
while (remaining) {
U32 const lastBlock = lastFrameChunk & (blockSize >= remaining);
size_t cSize;
if (dstCapacity < ZSTD_blockHeaderSize + MIN_CBLOCK_SIZE)
return ERROR(dstSize_tooSmall); /* not enough space to store compressed block */
if (remaining < blockSize) blockSize = remaining;
/* preemptive overflow correction */
if (cctx->lowLimit > (3U<<29)) {
U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->appliedParams.cParams.hashLog, cctx->appliedParams.cParams.strategy)) - 1;
U32 const current = (U32)(ip - cctx->base);
U32 const newCurrent = (current & cycleMask) + (1 << cctx->appliedParams.cParams.windowLog);
U32 const correction = current - newCurrent;
ZSTD_STATIC_ASSERT(ZSTD_WINDOWLOG_MAX_64 <= 30);
ZSTD_reduceIndex(cctx, correction);
cctx->base += correction;
cctx->dictBase += correction;
cctx->lowLimit -= correction;
cctx->dictLimit -= correction;
if (cctx->nextToUpdate < correction) cctx->nextToUpdate = 0;
else cctx->nextToUpdate -= correction;
}
if ((U32)(ip+blockSize - cctx->base) > cctx->loadedDictEnd + maxDist) {
/* enforce maxDist */
U32 const newLowLimit = (U32)(ip+blockSize - cctx->base) - maxDist;
if (cctx->lowLimit < newLowLimit) cctx->lowLimit = newLowLimit;
if (cctx->dictLimit < cctx->lowLimit) cctx->dictLimit = cctx->lowLimit;
}
cSize = ZSTD_compressBlock_internal(cctx, op+ZSTD_blockHeaderSize, dstCapacity-ZSTD_blockHeaderSize, ip, blockSize);
if (ZSTD_isError(cSize)) return cSize;
if (cSize == 0) { /* block is not compressible */
U32 const cBlockHeader24 = lastBlock + (((U32)bt_raw)<<1) + (U32)(blockSize << 3);
if (blockSize + ZSTD_blockHeaderSize > dstCapacity) return ERROR(dstSize_tooSmall);
MEM_writeLE32(op, cBlockHeader24); /* no pb, 4th byte will be overwritten */
memcpy(op + ZSTD_blockHeaderSize, ip, blockSize);
cSize = ZSTD_blockHeaderSize+blockSize;
} else {
U32 const cBlockHeader24 = lastBlock + (((U32)bt_compressed)<<1) + (U32)(cSize << 3);
MEM_writeLE24(op, cBlockHeader24);
cSize += ZSTD_blockHeaderSize;
}
remaining -= blockSize;
dstCapacity -= cSize;
ip += blockSize;
op += cSize;
}
if (lastFrameChunk && (op>ostart)) cctx->stage = ZSTDcs_ending;
return op-ostart;
}
static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
ZSTD_parameters params, U64 pledgedSrcSize, U32 dictID)
{ BYTE* const op = (BYTE*)dst;
U32 const dictIDSizeCodeLength = (dictID>0) + (dictID>=256) + (dictID>=65536); /* 0-3 */
U32 const dictIDSizeCode = params.fParams.noDictIDFlag ? 0 : dictIDSizeCodeLength; /* 0-3 */
U32 const checksumFlag = params.fParams.checksumFlag>0;
U32 const windowSize = 1U << params.cParams.windowLog;
U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize >= pledgedSrcSize);
BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
U32 const fcsCode = params.fParams.contentSizeFlag ?
(pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) : 0; /* 0-3 */
BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (singleSegment<<5) + (fcsCode<<6) );
size_t pos;
if (dstCapacity < ZSTD_frameHeaderSize_max) return ERROR(dstSize_tooSmall);
DEBUGLOG(5, "ZSTD_writeFrameHeader : dictIDFlag : %u ; dictID : %u ; dictIDSizeCode : %u",
!params.fParams.noDictIDFlag, dictID, dictIDSizeCode);
MEM_writeLE32(dst, ZSTD_MAGICNUMBER);
op[4] = frameHeaderDecriptionByte; pos=5;
if (!singleSegment) op[pos++] = windowLogByte;
switch(dictIDSizeCode)
{
default: assert(0); /* impossible */
case 0 : break;
case 1 : op[pos] = (BYTE)(dictID); pos++; break;
case 2 : MEM_writeLE16(op+pos, (U16)dictID); pos+=2; break;
case 3 : MEM_writeLE32(op+pos, dictID); pos+=4; break;
}
switch(fcsCode)
{
default: assert(0); /* impossible */
case 0 : if (singleSegment) op[pos++] = (BYTE)(pledgedSrcSize); break;
case 1 : MEM_writeLE16(op+pos, (U16)(pledgedSrcSize-256)); pos+=2; break;
case 2 : MEM_writeLE32(op+pos, (U32)(pledgedSrcSize)); pos+=4; break;
case 3 : MEM_writeLE64(op+pos, (U64)(pledgedSrcSize)); pos+=8; break;
}
return pos;
}
static size_t ZSTD_compressContinue_internal (ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
U32 frame, U32 lastFrameChunk)
{
const BYTE* const ip = (const BYTE*) src;
size_t fhSize = 0;
DEBUGLOG(5, "ZSTD_compressContinue_internal");
DEBUGLOG(5, "stage: %u", cctx->stage);
if (cctx->stage==ZSTDcs_created) return ERROR(stage_wrong); /* missing init (ZSTD_compressBegin) */
if (frame && (cctx->stage==ZSTDcs_init)) {
fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->appliedParams,
cctx->pledgedSrcSizePlusOne-1, cctx->dictID);
if (ZSTD_isError(fhSize)) return fhSize;
dstCapacity -= fhSize;
dst = (char*)dst + fhSize;
cctx->stage = ZSTDcs_ongoing;
}
/* Check if blocks follow each other */
if (src != cctx->nextSrc) {
/* not contiguous */
ptrdiff_t const delta = cctx->nextSrc - ip;
cctx->lowLimit = cctx->dictLimit;
cctx->dictLimit = (U32)(cctx->nextSrc - cctx->base);
cctx->dictBase = cctx->base;
cctx->base -= delta;
cctx->nextToUpdate = cctx->dictLimit;
if (cctx->dictLimit - cctx->lowLimit < HASH_READ_SIZE) cctx->lowLimit = cctx->dictLimit; /* too small extDict */
}
/* if input and dictionary overlap : reduce dictionary (area presumed modified by input) */
if ((ip+srcSize > cctx->dictBase + cctx->lowLimit) & (ip < cctx->dictBase + cctx->dictLimit)) {
ptrdiff_t const highInputIdx = (ip + srcSize) - cctx->dictBase;
U32 const lowLimitMax = (highInputIdx > (ptrdiff_t)cctx->dictLimit) ? cctx->dictLimit : (U32)highInputIdx;
cctx->lowLimit = lowLimitMax;
}
cctx->nextSrc = ip + srcSize;
if (srcSize) {
size_t const cSize = frame ?
ZSTD_compress_frameChunk (cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) :
ZSTD_compressBlock_internal (cctx, dst, dstCapacity, src, srcSize);
if (ZSTD_isError(cSize)) return cSize;
cctx->consumedSrcSize += srcSize;
return cSize + fhSize;
} else
return fhSize;
}
size_t ZSTD_compressContinue (ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize)
{
return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1 /* frame mode */, 0 /* last chunk */);
}
size_t ZSTD_getBlockSize(const ZSTD_CCtx* cctx)
{
U32 const cLevel = cctx->compressionLevel;
ZSTD_compressionParameters cParams = (cLevel == ZSTD_CLEVEL_CUSTOM) ?
cctx->appliedParams.cParams :
ZSTD_getCParams(cLevel, 0, 0);
return MIN (ZSTD_BLOCKSIZE_MAX, 1 << cParams.windowLog);
}
size_t ZSTD_compressBlock(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
size_t const blockSizeMax = ZSTD_getBlockSize(cctx);
if (srcSize > blockSizeMax) return ERROR(srcSize_wrong);
return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 0 /* frame mode */, 0 /* last chunk */);
}
/*! ZSTD_loadDictionaryContent() :
* @return : 0, or an error code
*/
static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx* zc, const void* src, size_t srcSize)
{
const BYTE* const ip = (const BYTE*) src;
const BYTE* const iend = ip + srcSize;
/* input becomes current prefix */
zc->lowLimit = zc->dictLimit;
zc->dictLimit = (U32)(zc->nextSrc - zc->base);
zc->dictBase = zc->base;
zc->base += ip - zc->nextSrc;
zc->nextToUpdate = zc->dictLimit;
zc->loadedDictEnd = zc->forceWindow ? 0 : (U32)(iend - zc->base);
zc->nextSrc = iend;
if (srcSize <= HASH_READ_SIZE) return 0;
switch(zc->appliedParams.cParams.strategy)
{
case ZSTD_fast:
ZSTD_fillHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
break;
case ZSTD_dfast:
ZSTD_fillDoubleHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
break;
case ZSTD_greedy:
case ZSTD_lazy:
case ZSTD_lazy2:
if (srcSize >= HASH_READ_SIZE)
ZSTD_insertAndFindFirstIndex(zc, iend-HASH_READ_SIZE, zc->appliedParams.cParams.searchLength);
break;
case ZSTD_btlazy2:
case ZSTD_btopt:
case ZSTD_btultra:
if (srcSize >= HASH_READ_SIZE)
ZSTD_updateTree(zc, iend-HASH_READ_SIZE, iend, 1 << zc->appliedParams.cParams.searchLog, zc->appliedParams.cParams.searchLength);
break;
default:
assert(0); /* not possible : not a valid strategy id */
}
zc->nextToUpdate = (U32)(iend - zc->base);
return 0;
}
/* Dictionaries that assign zero probability to symbols that show up causes problems
when FSE encoding. Refuse dictionaries that assign zero probability to symbols
that we may encounter during compression.
NOTE: This behavior is not standard and could be improved in the future. */
static size_t ZSTD_checkDictNCount(short* normalizedCounter, unsigned dictMaxSymbolValue, unsigned maxSymbolValue) {
U32 s;
if (dictMaxSymbolValue < maxSymbolValue) return ERROR(dictionary_corrupted);
for (s = 0; s <= maxSymbolValue; ++s) {
if (normalizedCounter[s] == 0) return ERROR(dictionary_corrupted);
}
return 0;
}
/* Dictionary format :
* See :
* https://github.com/facebook/zstd/blob/master/doc/zstd_compression_format.md#dictionary-format
*/
/*! ZSTD_loadZstdDictionary() :
* @return : 0, or an error code
* assumptions : magic number supposed already checked
* dictSize supposed > 8
*/
static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize)
{
const BYTE* dictPtr = (const BYTE*)dict;
const BYTE* const dictEnd = dictPtr + dictSize;
short offcodeNCount[MaxOff+1];
unsigned offcodeMaxValue = MaxOff;
BYTE scratchBuffer[1<<MAX(MLFSELog,LLFSELog)];
dictPtr += 4; /* skip magic number */
cctx->dictID = cctx->appliedParams.fParams.noDictIDFlag ? 0 : MEM_readLE32(dictPtr);
dictPtr += 4;
{ size_t const hufHeaderSize = HUF_readCTable(cctx->hufCTable, 255, dictPtr, dictEnd-dictPtr);
if (HUF_isError(hufHeaderSize)) return ERROR(dictionary_corrupted);
dictPtr += hufHeaderSize;
}
{ unsigned offcodeLog;
size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd-dictPtr);
if (FSE_isError(offcodeHeaderSize)) return ERROR(dictionary_corrupted);
if (offcodeLog > OffFSELog) return ERROR(dictionary_corrupted);
/* Defer checking offcodeMaxValue because we need to know the size of the dictionary content */
CHECK_E( FSE_buildCTable_wksp(cctx->offcodeCTable, offcodeNCount, offcodeMaxValue, offcodeLog, scratchBuffer, sizeof(scratchBuffer)),
dictionary_corrupted);
dictPtr += offcodeHeaderSize;
}
{ short matchlengthNCount[MaxML+1];
unsigned matchlengthMaxValue = MaxML, matchlengthLog;
size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd-dictPtr);
if (FSE_isError(matchlengthHeaderSize)) return ERROR(dictionary_corrupted);
if (matchlengthLog > MLFSELog) return ERROR(dictionary_corrupted);
/* Every match length code must have non-zero probability */
CHECK_F( ZSTD_checkDictNCount(matchlengthNCount, matchlengthMaxValue, MaxML));
CHECK_E( FSE_buildCTable_wksp(cctx->matchlengthCTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, scratchBuffer, sizeof(scratchBuffer)),
dictionary_corrupted);
dictPtr += matchlengthHeaderSize;
}
{ short litlengthNCount[MaxLL+1];
unsigned litlengthMaxValue = MaxLL, litlengthLog;
size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd-dictPtr);
if (FSE_isError(litlengthHeaderSize)) return ERROR(dictionary_corrupted);
if (litlengthLog > LLFSELog) return ERROR(dictionary_corrupted);
/* Every literal length code must have non-zero probability */
CHECK_F( ZSTD_checkDictNCount(litlengthNCount, litlengthMaxValue, MaxLL));
CHECK_E( FSE_buildCTable_wksp(cctx->litlengthCTable, litlengthNCount, litlengthMaxValue, litlengthLog, scratchBuffer, sizeof(scratchBuffer)),
dictionary_corrupted);
dictPtr += litlengthHeaderSize;
}
if (dictPtr+12 > dictEnd) return ERROR(dictionary_corrupted);
cctx->rep[0] = MEM_readLE32(dictPtr+0);
cctx->rep[1] = MEM_readLE32(dictPtr+4);
cctx->rep[2] = MEM_readLE32(dictPtr+8);
dictPtr += 12;
{ size_t const dictContentSize = (size_t)(dictEnd - dictPtr);
U32 offcodeMax = MaxOff;
if (dictContentSize <= ((U32)-1) - 128 KB) {
U32 const maxOffset = (U32)dictContentSize + 128 KB; /* The maximum offset that must be supported */
offcodeMax = ZSTD_highbit32(maxOffset); /* Calculate minimum offset code required to represent maxOffset */
}
/* All offset values <= dictContentSize + 128 KB must be representable */
CHECK_F (ZSTD_checkDictNCount(offcodeNCount, offcodeMaxValue, MIN(offcodeMax, MaxOff)));
/* All repCodes must be <= dictContentSize and != 0*/
{ U32 u;
for (u=0; u<3; u++) {
if (cctx->rep[u] == 0) return ERROR(dictionary_corrupted);
if (cctx->rep[u] > dictContentSize) return ERROR(dictionary_corrupted);
} }
cctx->fseCTables_ready = 1;
cctx->hufCTable_repeatMode = HUF_repeat_valid;
return ZSTD_loadDictionaryContent(cctx, dictPtr, dictContentSize);
}
}
/** ZSTD_compress_insertDictionary() :
* @return : 0, or an error code */
static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx* cctx,
const void* dict, size_t dictSize,
ZSTD_dictMode_e dictMode)
{
DEBUGLOG(5, "ZSTD_compress_insertDictionary");
if ((dict==NULL) || (dictSize<=8)) return 0;
/* dict restricted modes */
if (dictMode==ZSTD_dm_rawContent)
return ZSTD_loadDictionaryContent(cctx, dict, dictSize);
if (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) {
if (dictMode == ZSTD_dm_auto) {
DEBUGLOG(5, "raw content dictionary detected");
return ZSTD_loadDictionaryContent(cctx, dict, dictSize);
}
if (dictMode == ZSTD_dm_fullDict)
return ERROR(dictionary_wrong);
assert(0); /* impossible */
}
/* dict as full zstd dictionary */
return ZSTD_loadZstdDictionary(cctx, dict, dictSize);
}
/*! ZSTD_compressBegin_internal() :
* @return : 0, or an error code */
static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* cctx,
const void* dict, size_t dictSize,
ZSTD_dictMode_e dictMode,
const ZSTD_CDict* cdict,
ZSTD_parameters params, U64 pledgedSrcSize,
ZSTD_buffered_policy_e zbuff)
{
DEBUGLOG(4, "ZSTD_compressBegin_internal");
DEBUGLOG(4, "dict ? %s", dict ? "dict" : (cdict ? "cdict" : "none"));
DEBUGLOG(4, "dictMode : %u", (U32)dictMode);
/* params are supposed to be fully validated at this point */
assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
assert(!((dict) && (cdict))); /* either dict or cdict, not both */
if (cdict && cdict->dictContentSize>0) {
return ZSTD_copyCCtx_internal(cctx, cdict->refContext,
params.fParams, pledgedSrcSize,
zbuff);
}
CHECK_F( ZSTD_resetCCtx_internal(cctx, params, pledgedSrcSize,
ZSTDcrp_continue, zbuff) );
return ZSTD_compress_insertDictionary(cctx, dict, dictSize, dictMode);
}
/*! ZSTD_compressBegin_advanced() :
* @return : 0, or an error code */
size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx,
const void* dict, size_t dictSize,
ZSTD_parameters params, unsigned long long pledgedSrcSize)
{
/* compression parameters verification and optimization */
CHECK_F(ZSTD_checkCParams(params.cParams));
return ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
params, pledgedSrcSize, ZSTDb_not_buffered);
}
size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel)
{
ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
return ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
params, 0, ZSTDb_not_buffered);
}
size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel)
{
return ZSTD_compressBegin_usingDict(cctx, NULL, 0, compressionLevel);
}
/*! ZSTD_writeEpilogue() :
* Ends a frame.
* @return : nb of bytes written into dst (or an error code) */
static size_t ZSTD_writeEpilogue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
{
BYTE* const ostart = (BYTE*)dst;
BYTE* op = ostart;
size_t fhSize = 0;
DEBUGLOG(5, "ZSTD_writeEpilogue");
if (cctx->stage == ZSTDcs_created) return ERROR(stage_wrong); /* init missing */
/* special case : empty frame */
if (cctx->stage == ZSTDcs_init) {
fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->appliedParams, 0, 0);
if (ZSTD_isError(fhSize)) return fhSize;
dstCapacity -= fhSize;
op += fhSize;
cctx->stage = ZSTDcs_ongoing;
}
if (cctx->stage != ZSTDcs_ending) {
/* write one last empty block, make it the "last" block */
U32 const cBlockHeader24 = 1 /* last block */ + (((U32)bt_raw)<<1) + 0;
if (dstCapacity<4) return ERROR(dstSize_tooSmall);
MEM_writeLE32(op, cBlockHeader24);
op += ZSTD_blockHeaderSize;
dstCapacity -= ZSTD_blockHeaderSize;
}
if (cctx->appliedParams.fParams.checksumFlag) {
U32 const checksum = (U32) XXH64_digest(&cctx->xxhState);
if (dstCapacity<4) return ERROR(dstSize_tooSmall);
MEM_writeLE32(op, checksum);
op += 4;
}
cctx->stage = ZSTDcs_created; /* return to "created but no init" status */
return op-ostart;
}
size_t ZSTD_compressEnd (ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize)
{
size_t endResult;
size_t const cSize = ZSTD_compressContinue_internal(cctx,
dst, dstCapacity, src, srcSize,
1 /* frame mode */, 1 /* last chunk */);
if (ZSTD_isError(cSize)) return cSize;
endResult = ZSTD_writeEpilogue(cctx, (char*)dst + cSize, dstCapacity-cSize);
if (ZSTD_isError(endResult)) return endResult;
if (cctx->appliedParams.fParams.contentSizeFlag) { /* control src size */
DEBUGLOG(5, "end of frame : controlling src size");
if (cctx->pledgedSrcSizePlusOne != cctx->consumedSrcSize+1) {
DEBUGLOG(5, "error : pledgedSrcSize = %u, while realSrcSize = %u",
(U32)cctx->pledgedSrcSizePlusOne-1, (U32)cctx->consumedSrcSize);
return ERROR(srcSize_wrong);
} }
return cSize + endResult;
}
static size_t ZSTD_compress_internal (ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const void* dict,size_t dictSize,
ZSTD_parameters params)
{
CHECK_F( ZSTD_compressBegin_internal(cctx, dict, dictSize, ZSTD_dm_auto, NULL,
params, srcSize, ZSTDb_not_buffered) );
return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize);
}
size_t ZSTD_compress_advanced (ZSTD_CCtx* ctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const void* dict,size_t dictSize,
ZSTD_parameters params)
{
CHECK_F(ZSTD_checkCParams(params.cParams));
return ZSTD_compress_internal(ctx, dst, dstCapacity, src, srcSize, dict, dictSize, params);
}
size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize,
const void* dict, size_t dictSize, int compressionLevel)
{
ZSTD_parameters params = ZSTD_getParams(compressionLevel, srcSize, dict ? dictSize : 0);
params.fParams.contentSizeFlag = 1;
return ZSTD_compress_internal(ctx, dst, dstCapacity, src, srcSize, dict, dictSize, params);
}
size_t ZSTD_compressCCtx (ZSTD_CCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel)
{
return ZSTD_compress_usingDict(ctx, dst, dstCapacity, src, srcSize, NULL, 0, compressionLevel);
}
size_t ZSTD_compress(void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel)
{
size_t result;
ZSTD_CCtx ctxBody;
memset(&ctxBody, 0, sizeof(ctxBody));
ctxBody.customMem = ZSTD_defaultCMem;
result = ZSTD_compressCCtx(&ctxBody, dst, dstCapacity, src, srcSize, compressionLevel);
ZSTD_free(ctxBody.workSpace, ZSTD_defaultCMem); /* can't free ctxBody itself, as it's on stack; free only heap content */
return result;
}
/* ===== Dictionary API ===== */
/*! ZSTD_estimateCDictSize_advanced() :
* Estimate amount of memory that will be needed to create a dictionary with following arguments */
size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, unsigned byReference)
{
DEBUGLOG(5, "sizeof(ZSTD_CDict) : %u", (U32)sizeof(ZSTD_CDict));
DEBUGLOG(5, "CCtx estimate : %u", (U32)ZSTD_estimateCCtxSize_advanced(cParams));
return sizeof(ZSTD_CDict) + ZSTD_estimateCCtxSize_advanced(cParams)
+ (byReference ? 0 : dictSize);
}
size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel)
{
ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
return ZSTD_estimateCDictSize_advanced(dictSize, cParams, 0);
}
size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict)
{
if (cdict==NULL) return 0; /* support sizeof on NULL */
DEBUGLOG(5, "sizeof(*cdict) : %u", (U32)sizeof(*cdict));
DEBUGLOG(5, "ZSTD_sizeof_CCtx : %u", (U32)ZSTD_sizeof_CCtx(cdict->refContext));
return ZSTD_sizeof_CCtx(cdict->refContext) + (cdict->dictBuffer ? cdict->dictContentSize : 0) + sizeof(*cdict);
}
static ZSTD_parameters ZSTD_makeParams(ZSTD_compressionParameters cParams, ZSTD_frameParameters fParams)
{
ZSTD_parameters params;
params.cParams = cParams;
params.fParams = fParams;
return params;
}
static size_t ZSTD_initCDict_internal(
ZSTD_CDict* cdict,
const void* dictBuffer, size_t dictSize,
unsigned byReference, ZSTD_dictMode_e dictMode,
ZSTD_compressionParameters cParams)
{
DEBUGLOG(5, "ZSTD_initCDict_internal, mode %u", (U32)dictMode);
if ((byReference) || (!dictBuffer) || (!dictSize)) {
cdict->dictBuffer = NULL;
cdict->dictContent = dictBuffer;
} else {
void* const internalBuffer = ZSTD_malloc(dictSize, cdict->refContext->customMem);
cdict->dictBuffer = internalBuffer;
cdict->dictContent = internalBuffer;
if (!internalBuffer) return ERROR(memory_allocation);
memcpy(internalBuffer, dictBuffer, dictSize);
}
cdict->dictContentSize = dictSize;
{ ZSTD_frameParameters const fParams = { 0 /* contentSizeFlag */,
0 /* checksumFlag */, 0 /* noDictIDFlag */ }; /* dummy */
ZSTD_parameters const params = ZSTD_makeParams(cParams, fParams);
CHECK_F( ZSTD_compressBegin_internal(cdict->refContext,
cdict->dictContent, dictSize, dictMode,
NULL,
params, ZSTD_CONTENTSIZE_UNKNOWN,
ZSTDb_not_buffered) );
}
return 0;
}
ZSTD_CDict* ZSTD_createCDict_advanced(const void* dictBuffer, size_t dictSize,
unsigned byReference, ZSTD_dictMode_e dictMode,
ZSTD_compressionParameters cParams, ZSTD_customMem customMem)
{
DEBUGLOG(5, "ZSTD_createCDict_advanced, mode %u", (U32)dictMode);
if (!customMem.customAlloc ^ !customMem.customFree) return NULL;
{ ZSTD_CDict* const cdict = (ZSTD_CDict*)ZSTD_malloc(sizeof(ZSTD_CDict), customMem);
ZSTD_CCtx* const cctx = ZSTD_createCCtx_advanced(customMem);
if (!cdict || !cctx) {
ZSTD_free(cdict, customMem);
ZSTD_freeCCtx(cctx);
return NULL;
}
cdict->refContext = cctx;
if (ZSTD_isError( ZSTD_initCDict_internal(cdict,
dictBuffer, dictSize,
byReference, dictMode,
cParams) )) {
ZSTD_freeCDict(cdict);
return NULL;
}
return cdict;
}
}
ZSTD_CDict* ZSTD_createCDict(const void* dict, size_t dictSize, int compressionLevel)
{
ZSTD_compressionParameters cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
return ZSTD_createCDict_advanced(dict, dictSize,
0 /* byReference */, ZSTD_dm_auto,
cParams, ZSTD_defaultCMem);
}
ZSTD_CDict* ZSTD_createCDict_byReference(const void* dict, size_t dictSize, int compressionLevel)
{
ZSTD_compressionParameters cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
return ZSTD_createCDict_advanced(dict, dictSize,
1 /* byReference */, ZSTD_dm_auto,
cParams, ZSTD_defaultCMem);
}
size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
{
if (cdict==NULL) return 0; /* support free on NULL */
{ ZSTD_customMem const cMem = cdict->refContext->customMem;
ZSTD_freeCCtx(cdict->refContext);
ZSTD_free(cdict->dictBuffer, cMem);
ZSTD_free(cdict, cMem);
return 0;
}
}
/*! ZSTD_initStaticCDict_advanced() :
* Generate a digested dictionary in provided memory area.
* workspace: The memory area to emplace the dictionary into.
* Provided pointer must 8-bytes aligned.
* It must outlive dictionary usage.
* workspaceSize: Use ZSTD_estimateCDictSize()
* to determine how large workspace must be.
* cParams : use ZSTD_getCParams() to transform a compression level
* into its relevants cParams.
* @return : pointer to ZSTD_CDict*, or NULL if error (size too small)
* Note : there is no corresponding "free" function.
* Since workspace was allocated externally, it must be freed externally.
*/
ZSTD_CDict* ZSTD_initStaticCDict(void* workspace, size_t workspaceSize,
const void* dict, size_t dictSize,
unsigned byReference, ZSTD_dictMode_e dictMode,
ZSTD_compressionParameters cParams)
{
size_t const cctxSize = ZSTD_estimateCCtxSize_advanced(cParams);
size_t const neededSize = sizeof(ZSTD_CDict) + (byReference ? 0 : dictSize)
+ cctxSize;
ZSTD_CDict* const cdict = (ZSTD_CDict*) workspace;
void* ptr;
DEBUGLOG(5, "(size_t)workspace & 7 : %u", (U32)(size_t)workspace & 7);
if ((size_t)workspace & 7) return NULL; /* 8-aligned */
DEBUGLOG(5, "(workspaceSize < neededSize) : (%u < %u) => %u",
(U32)workspaceSize, (U32)neededSize, (U32)(workspaceSize < neededSize));
if (workspaceSize < neededSize) return NULL;
if (!byReference) {
memcpy(cdict+1, dict, dictSize);
dict = cdict+1;
ptr = (char*)workspace + sizeof(ZSTD_CDict) + dictSize;
} else {
ptr = cdict+1;
}
cdict->refContext = ZSTD_initStaticCCtx(ptr, cctxSize);
if (ZSTD_isError( ZSTD_initCDict_internal(cdict,
dict, dictSize,
1 /* byReference */, dictMode,
cParams) ))
return NULL;
return cdict;
}
ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict* cdict) {
return ZSTD_getParamsFromCCtx(cdict->refContext);
}
/* ZSTD_compressBegin_usingCDict_advanced() :
* cdict must be != NULL */
size_t ZSTD_compressBegin_usingCDict_advanced(
ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict,
ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize)
{
if (cdict==NULL) return ERROR(dictionary_wrong);
{ ZSTD_parameters params = cdict->refContext->appliedParams;
params.fParams = fParams;
DEBUGLOG(5, "ZSTD_compressBegin_usingCDict_advanced");
return ZSTD_compressBegin_internal(cctx,
NULL, 0, ZSTD_dm_auto,
cdict,
params, pledgedSrcSize,
ZSTDb_not_buffered);
}
}
/* ZSTD_compressBegin_usingCDict() :
* pledgedSrcSize=0 means "unknown"
* if pledgedSrcSize>0, it will enable contentSizeFlag */
size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict)
{
ZSTD_frameParameters const fParams = { 0 /*content*/, 0 /*checksum*/, 0 /*noDictID*/ };
DEBUGLOG(5, "ZSTD_compressBegin_usingCDict : dictIDFlag == %u", !fParams.noDictIDFlag);
return ZSTD_compressBegin_usingCDict_advanced(cctx, cdict, fParams, 0);
}
size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const ZSTD_CDict* cdict, ZSTD_frameParameters fParams)
{
CHECK_F (ZSTD_compressBegin_usingCDict_advanced(cctx, cdict, fParams, srcSize)); /* will check if cdict != NULL */
return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize);
}
/*! ZSTD_compress_usingCDict() :
* Compression using a digested Dictionary.
* Faster startup than ZSTD_compress_usingDict(), recommended when same dictionary is used multiple times.
* Note that compression parameters are decided at CDict creation time
* while frame parameters are hardcoded */
size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const ZSTD_CDict* cdict)
{
ZSTD_frameParameters const fParams = { 1 /*content*/, 0 /*checksum*/, 0 /*noDictID*/ };
return ZSTD_compress_usingCDict_advanced(cctx, dst, dstCapacity, src, srcSize, cdict, fParams);
}
/* ******************************************************************
* Streaming
********************************************************************/
ZSTD_CStream* ZSTD_createCStream(void)
{
return ZSTD_createCStream_advanced(ZSTD_defaultCMem);
}
ZSTD_CStream* ZSTD_initStaticCStream(void *workspace, size_t workspaceSize)
{
return ZSTD_initStaticCCtx(workspace, workspaceSize);
}
ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem)
{ /* CStream and CCtx are now same object */
return ZSTD_createCCtx_advanced(customMem);
}
size_t ZSTD_freeCStream(ZSTD_CStream* zcs)
{
return ZSTD_freeCCtx(zcs); /* same object */
}
/*====== Initialization ======*/
size_t ZSTD_CStreamInSize(void) { return ZSTD_BLOCKSIZE_MAX; }
size_t ZSTD_CStreamOutSize(void)
{
return ZSTD_compressBound(ZSTD_BLOCKSIZE_MAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */ ;
}
static size_t ZSTD_resetCStream_internal(ZSTD_CStream* zcs,
const void* dict, size_t dictSize, ZSTD_dictMode_e dictMode,
const ZSTD_CDict* cdict,
ZSTD_parameters params, unsigned long long pledgedSrcSize)
{
DEBUGLOG(4, "ZSTD_resetCStream_internal");
/* params are supposed to be fully validated at this point */
assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
assert(!((dict) && (cdict))); /* either dict or cdict, not both */
CHECK_F( ZSTD_compressBegin_internal(zcs,
dict, dictSize, dictMode,
cdict,
params, pledgedSrcSize,
ZSTDb_buffered) );
zcs->inToCompress = 0;
zcs->inBuffPos = 0;
zcs->inBuffTarget = zcs->blockSize;
zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
zcs->streamStage = zcss_load;
zcs->frameEnded = 0;
return 0; /* ready to go */
}
size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
{
ZSTD_parameters params = zcs->requestedParams;
params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
DEBUGLOG(5, "ZSTD_resetCStream");
if (zcs->compressionLevel != ZSTD_CLEVEL_CUSTOM) {
params.cParams = ZSTD_getCParams(zcs->compressionLevel, pledgedSrcSize, 0 /* dictSize */);
}
return ZSTD_resetCStream_internal(zcs, NULL, 0, zcs->dictMode, zcs->cdict, params, pledgedSrcSize);
}
/*! ZSTD_initCStream_internal() :
* Note : not static, but hidden (not exposed). Used by zstdmt_compress.c
* Assumption 1 : params are valid
* Assumption 2 : either dict, or cdict, is defined, not both */
size_t ZSTD_initCStream_internal(ZSTD_CStream* zcs,
const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
ZSTD_parameters params, unsigned long long pledgedSrcSize)
{
DEBUGLOG(5, "ZSTD_initCStream_internal");
assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
assert(!((dict) && (cdict))); /* either dict or cdict, not both */
if (dict && dictSize >= 8) {
DEBUGLOG(5, "loading dictionary of size %u", (U32)dictSize);
if (zcs->staticSize) { /* static CCtx : never uses malloc */
/* incompatible with internal cdict creation */
return ERROR(memory_allocation);
}
ZSTD_freeCDict(zcs->cdictLocal);
zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize,
zcs->dictContentByRef, zcs->dictMode,
params.cParams, zcs->customMem);
zcs->cdict = zcs->cdictLocal;
if (zcs->cdictLocal == NULL) return ERROR(memory_allocation);
} else {
if (cdict) {
ZSTD_parameters const cdictParams = ZSTD_getParamsFromCDict(cdict);
params.cParams = cdictParams.cParams; /* cParams are enforced from cdict */
}
ZSTD_freeCDict(zcs->cdictLocal);
zcs->cdictLocal = NULL;
zcs->cdict = cdict;
}
zcs->requestedParams = params;
zcs->compressionLevel = ZSTD_CLEVEL_CUSTOM;
return ZSTD_resetCStream_internal(zcs, NULL, 0, zcs->dictMode, zcs->cdict, params, pledgedSrcSize);
}
/* ZSTD_initCStream_usingCDict_advanced() :
* same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs,
const ZSTD_CDict* cdict,
ZSTD_frameParameters fParams,
unsigned long long pledgedSrcSize)
{ /* cannot handle NULL cdict (does not know what to do) */
if (!cdict) return ERROR(dictionary_wrong);
{ ZSTD_parameters params = ZSTD_getParamsFromCDict(cdict);
params.fParams = fParams;
return ZSTD_initCStream_internal(zcs,
NULL, 0, cdict,
params, pledgedSrcSize);
}
}
/* note : cdict must outlive compression session */
size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict)
{
ZSTD_frameParameters const fParams = { 0 /* contentSize */, 0 /* checksum */, 0 /* hideDictID */ };
return ZSTD_initCStream_usingCDict_advanced(zcs, cdict, fParams, 0); /* note : will check that cdict != NULL */
}
size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
const void* dict, size_t dictSize,
ZSTD_parameters params, unsigned long long pledgedSrcSize)
{
CHECK_F( ZSTD_checkCParams(params.cParams) );
zcs->requestedParams = params;
zcs->compressionLevel = ZSTD_CLEVEL_CUSTOM;
return ZSTD_initCStream_internal(zcs, dict, dictSize, NULL, params, pledgedSrcSize);
}
size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel)
{
ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
zcs->compressionLevel = compressionLevel;
return ZSTD_initCStream_internal(zcs, dict, dictSize, NULL, params, 0);
}
size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize)
{
ZSTD_parameters params = ZSTD_getParams(compressionLevel, pledgedSrcSize, 0);
params.fParams.contentSizeFlag = (pledgedSrcSize>0);
return ZSTD_initCStream_internal(zcs, NULL, 0, NULL, params, pledgedSrcSize);
}
size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel)
{
ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, 0);
return ZSTD_initCStream_internal(zcs, NULL, 0, NULL, params, 0);
}
/*====== Compression ======*/
MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity,
const void* src, size_t srcSize)
{
size_t const length = MIN(dstCapacity, srcSize);
if (length) memcpy(dst, src, length);
return length;
}
/** ZSTD_compressStream_generic():
* internal function for all *compressStream*() variants and *compress_generic()
* @return : hint size for next input */
size_t ZSTD_compressStream_generic(ZSTD_CStream* zcs,
ZSTD_outBuffer* output,
ZSTD_inBuffer* input,
ZSTD_EndDirective const flushMode)
{
const char* const istart = (const char*)input->src;
const char* const iend = istart + input->size;
const char* ip = istart + input->pos;
char* const ostart = (char*)output->dst;
char* const oend = ostart + output->size;
char* op = ostart + output->pos;
U32 someMoreWork = 1;
/* check expectations */
DEBUGLOG(5, "ZSTD_compressStream_generic, flush=%u", (U32)flushMode);
assert(zcs->inBuff != NULL);
assert(zcs->inBuffSize>0);
assert(zcs->outBuff!= NULL);
assert(zcs->outBuffSize>0);
assert(output->pos <= output->size);
assert(input->pos <= input->size);
while (someMoreWork) {
switch(zcs->streamStage)
{
case zcss_init:
/* call ZSTD_initCStream() first ! */
return ERROR(init_missing);
case zcss_load:
if ( (flushMode == ZSTD_e_end)
&& ((size_t)(oend-op) >= ZSTD_compressBound(iend-ip)) /* enough dstCapacity */
&& (zcs->inBuffPos == 0) ) {
/* shortcut to compression pass directly into output buffer */
size_t const cSize = ZSTD_compressEnd(zcs,
op, oend-op, ip, iend-ip);
DEBUGLOG(4, "ZSTD_compressEnd : %u", (U32)cSize);
if (ZSTD_isError(cSize)) return cSize;
ip = iend;
op += cSize;
zcs->frameEnded = 1;
ZSTD_startNewCompression(zcs);
someMoreWork = 0; break;
}
/* complete loading into inBuffer */
{ size_t const toLoad = zcs->inBuffTarget - zcs->inBuffPos;
size_t const loaded = ZSTD_limitCopy(
zcs->inBuff + zcs->inBuffPos, toLoad,
ip, iend-ip);
zcs->inBuffPos += loaded;
ip += loaded;
if ( (flushMode == ZSTD_e_continue)
&& (zcs->inBuffPos < zcs->inBuffTarget) ) {
/* not enough input to fill full block : stop here */
someMoreWork = 0; break;
}
if ( (flushMode == ZSTD_e_flush)
&& (zcs->inBuffPos == zcs->inToCompress) ) {
/* empty */
someMoreWork = 0; break;
}
}
/* compress current block (note : this stage cannot be stopped in the middle) */
DEBUGLOG(5, "stream compression stage (flushMode==%u)", flushMode);
{ void* cDst;
size_t cSize;
size_t const iSize = zcs->inBuffPos - zcs->inToCompress;
size_t oSize = oend-op;
unsigned const lastBlock = (flushMode == ZSTD_e_end) && (ip==iend);
if (oSize >= ZSTD_compressBound(iSize))
cDst = op; /* compress into output buffer, to skip flush stage */
else
cDst = zcs->outBuff, oSize = zcs->outBuffSize;
cSize = lastBlock ?
ZSTD_compressEnd(zcs, cDst, oSize,
zcs->inBuff + zcs->inToCompress, iSize) :
ZSTD_compressContinue(zcs, cDst, oSize,
zcs->inBuff + zcs->inToCompress, iSize);
if (ZSTD_isError(cSize)) return cSize;
zcs->frameEnded = lastBlock;
/* prepare next block */
zcs->inBuffTarget = zcs->inBuffPos + zcs->blockSize;
if (zcs->inBuffTarget > zcs->inBuffSize)
zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize;
DEBUGLOG(5, "inBuffTarget:%u / inBuffSize:%u",
(U32)zcs->inBuffTarget, (U32)zcs->inBuffSize);
if (!lastBlock)
assert(zcs->inBuffTarget <= zcs->inBuffSize);
zcs->inToCompress = zcs->inBuffPos;
if (cDst == op) { /* no need to flush */
op += cSize;
if (zcs->frameEnded) {
DEBUGLOG(5, "Frame completed directly in outBuffer");
someMoreWork = 0;
ZSTD_startNewCompression(zcs);
}
break;
}
zcs->outBuffContentSize = cSize;
zcs->outBuffFlushedSize = 0;
zcs->streamStage = zcss_flush; /* pass-through to flush stage */
}
/* fall-through */
case zcss_flush:
DEBUGLOG(5, "flush stage");
{ size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
size_t const flushed = ZSTD_limitCopy(op, oend-op,
zcs->outBuff + zcs->outBuffFlushedSize, toFlush);
DEBUGLOG(5, "toFlush: %u into %u ==> flushed: %u",
(U32)toFlush, (U32)(oend-op), (U32)flushed);
op += flushed;
zcs->outBuffFlushedSize += flushed;
if (toFlush!=flushed) {
/* flush not fully completed, presumably because dst is too small */
assert(op==oend);
someMoreWork = 0;
break;
}
zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0;
if (zcs->frameEnded) {
DEBUGLOG(5, "Frame completed on flush");
someMoreWork = 0;
ZSTD_startNewCompression(zcs);
break;
}
zcs->streamStage = zcss_load;
break;
}
default: /* impossible */
assert(0);
}
}
input->pos = ip - istart;
output->pos = op - ostart;
if (zcs->frameEnded) return 0;
{ size_t hintInSize = zcs->inBuffTarget - zcs->inBuffPos;
if (hintInSize==0) hintInSize = zcs->blockSize;
return hintInSize;
}
}
size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input)
{
/* check conditions */
if (output->pos > output->size) return ERROR(GENERIC);
if (input->pos > input->size) return ERROR(GENERIC);
return ZSTD_compressStream_generic(zcs, output, input, ZSTD_e_continue);
}
/*! ZSTDMT_initCStream_internal() :
* Private use only. Init streaming operation.
* expects params to be valid.
* must receive dict, or cdict, or none, but not both.
* @return : 0, or an error code */
size_t ZSTDMT_initCStream_internal(ZSTDMT_CCtx* zcs,
const void* dict, size_t dictSize, const ZSTD_CDict* cdict,
ZSTD_parameters params, unsigned long long pledgedSrcSize);
size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
ZSTD_outBuffer* output,
ZSTD_inBuffer* input,
ZSTD_EndDirective endOp)
{
/* check conditions */
if (output->pos > output->size) return ERROR(GENERIC);
if (input->pos > input->size) return ERROR(GENERIC);
assert(cctx!=NULL);
/* transparent initialization stage */
if (cctx->streamStage == zcss_init) {
const void* const prefix = cctx->prefix;
size_t const prefixSize = cctx->prefixSize;
ZSTD_parameters params = cctx->requestedParams;
if (cctx->compressionLevel != ZSTD_CLEVEL_CUSTOM)
params.cParams = ZSTD_getCParams(cctx->compressionLevel,
cctx->pledgedSrcSizePlusOne-1, 0 /*dictSize*/);
cctx->prefix = NULL; cctx->prefixSize = 0; /* single usage */
assert(prefix==NULL || cctx->cdict==NULL); /* only one can be set */
#ifdef ZSTD_MULTITHREAD
if (cctx->nbThreads > 1) {
DEBUGLOG(4, "call ZSTDMT_initCStream_internal as nbThreads=%u", cctx->nbThreads);
CHECK_F( ZSTDMT_initCStream_internal(cctx->mtctx, prefix, prefixSize, cctx->cdict, params, cctx->pledgedSrcSizePlusOne-1) );
cctx->streamStage = zcss_load;
} else
#endif
{
CHECK_F( ZSTD_resetCStream_internal(cctx, prefix, prefixSize, cctx->dictMode, cctx->cdict, params, cctx->pledgedSrcSizePlusOne-1) );
} }
/* compression stage */
#ifdef ZSTD_MULTITHREAD
if (cctx->nbThreads > 1) {
size_t const flushMin = ZSTDMT_compressStream_generic(cctx->mtctx, output, input, endOp);
DEBUGLOG(5, "ZSTDMT_compressStream_generic : %u", (U32)flushMin);
if ( ZSTD_isError(flushMin)
|| (endOp == ZSTD_e_end && flushMin == 0) ) { /* compression completed */
ZSTD_startNewCompression(cctx);
}
return flushMin;
}
#endif
CHECK_F( ZSTD_compressStream_generic(cctx, output, input, endOp) );
DEBUGLOG(5, "completed ZSTD_compress_generic");
return cctx->outBuffContentSize - cctx->outBuffFlushedSize; /* remaining to flush */
}
size_t ZSTD_compress_generic_simpleArgs (
ZSTD_CCtx* cctx,
void* dst, size_t dstCapacity, size_t* dstPos,
const void* src, size_t srcSize, size_t* srcPos,
ZSTD_EndDirective endOp)
{
ZSTD_outBuffer output = { dst, dstCapacity, *dstPos };
ZSTD_inBuffer input = { src, srcSize, *srcPos };
/* ZSTD_compress_generic() will check validity of dstPos and srcPos */
size_t const cErr = ZSTD_compress_generic(cctx, &output, &input, endOp);
*dstPos = output.pos;
*srcPos = input.pos;
return cErr;
}
/*====== Finalize ======*/
/*! ZSTD_flushStream() :
* @return : amount of data remaining to flush */
size_t ZSTD_flushStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output)
{
ZSTD_inBuffer input = { NULL, 0, 0 };
if (output->pos > output->size) return ERROR(GENERIC);
CHECK_F( ZSTD_compressStream_generic(zcs, output, &input, ZSTD_e_flush) );
return zcs->outBuffContentSize - zcs->outBuffFlushedSize; /* remaining to flush */
}
size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output)
{
ZSTD_inBuffer input = { NULL, 0, 0 };
if (output->pos > output->size) return ERROR(GENERIC);
CHECK_F( ZSTD_compressStream_generic(zcs, output, &input, ZSTD_e_end) );
{ size_t const lastBlockSize = zcs->frameEnded ? 0 : ZSTD_BLOCKHEADERSIZE;
size_t const checksumSize = zcs->frameEnded ? 0 : zcs->appliedParams.fParams.checksumFlag * 4;
size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize + lastBlockSize + checksumSize;
DEBUGLOG(5, "ZSTD_endStream : remaining to flush : %u",
(unsigned)toFlush);
return toFlush;
}
}
/*-===== Pre-defined compression levels =====-*/
#define ZSTD_MAX_CLEVEL 22
int ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; }
static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEVEL+1] = {
{ /* "default" - guarantees a monotonically increasing memory budget */
/* W, C, H, S, L, TL, strat */
{ 18, 12, 12, 1, 7, 16, ZSTD_fast }, /* level 0 - never used */
{ 19, 13, 14, 1, 7, 16, ZSTD_fast }, /* level 1 */
{ 19, 15, 16, 1, 6, 16, ZSTD_fast }, /* level 2 */
{ 20, 16, 17, 1, 5, 16, ZSTD_dfast }, /* level 3 */
{ 20, 17, 18, 1, 5, 16, ZSTD_dfast }, /* level 4 */
{ 20, 17, 18, 2, 5, 16, ZSTD_greedy }, /* level 5 */
{ 21, 17, 19, 2, 5, 16, ZSTD_lazy }, /* level 6 */
{ 21, 18, 19, 3, 5, 16, ZSTD_lazy }, /* level 7 */
{ 21, 18, 20, 3, 5, 16, ZSTD_lazy2 }, /* level 8 */
{ 21, 19, 20, 3, 5, 16, ZSTD_lazy2 }, /* level 9 */
{ 21, 19, 21, 4, 5, 16, ZSTD_lazy2 }, /* level 10 */
{ 22, 20, 22, 4, 5, 16, ZSTD_lazy2 }, /* level 11 */
{ 22, 20, 22, 5, 5, 16, ZSTD_lazy2 }, /* level 12 */
{ 22, 21, 22, 5, 5, 16, ZSTD_lazy2 }, /* level 13 */
{ 22, 21, 22, 6, 5, 16, ZSTD_lazy2 }, /* level 14 */
{ 22, 21, 22, 5, 5, 16, ZSTD_btlazy2 }, /* level 15 */
{ 23, 22, 22, 5, 5, 16, ZSTD_btlazy2 }, /* level 16 */
{ 23, 22, 22, 4, 5, 24, ZSTD_btopt }, /* level 17 */
{ 23, 22, 22, 5, 4, 32, ZSTD_btopt }, /* level 18 */
{ 23, 23, 22, 6, 3, 48, ZSTD_btopt }, /* level 19 */
{ 25, 25, 23, 7, 3, 64, ZSTD_btultra }, /* level 20 */
{ 26, 26, 24, 7, 3,256, ZSTD_btultra }, /* level 21 */
{ 27, 27, 25, 9, 3,512, ZSTD_btultra }, /* level 22 */
},
{ /* for srcSize <= 256 KB */
/* W, C, H, S, L, T, strat */
{ 0, 0, 0, 0, 0, 0, ZSTD_fast }, /* level 0 - not used */
{ 18, 13, 14, 1, 6, 8, ZSTD_fast }, /* level 1 */
{ 18, 14, 13, 1, 5, 8, ZSTD_dfast }, /* level 2 */
{ 18, 16, 15, 1, 5, 8, ZSTD_dfast }, /* level 3 */
{ 18, 15, 17, 1, 5, 8, ZSTD_greedy }, /* level 4.*/
{ 18, 16, 17, 4, 5, 8, ZSTD_greedy }, /* level 5.*/
{ 18, 16, 17, 3, 5, 8, ZSTD_lazy }, /* level 6.*/
{ 18, 17, 17, 4, 4, 8, ZSTD_lazy }, /* level 7 */
{ 18, 17, 17, 4, 4, 8, ZSTD_lazy2 }, /* level 8 */
{ 18, 17, 17, 5, 4, 8, ZSTD_lazy2 }, /* level 9 */
{ 18, 17, 17, 6, 4, 8, ZSTD_lazy2 }, /* level 10 */
{ 18, 18, 17, 6, 4, 8, ZSTD_lazy2 }, /* level 11.*/
{ 18, 18, 17, 7, 4, 8, ZSTD_lazy2 }, /* level 12.*/
{ 18, 19, 17, 6, 4, 8, ZSTD_btlazy2 }, /* level 13 */
{ 18, 18, 18, 4, 4, 16, ZSTD_btopt }, /* level 14.*/
{ 18, 18, 18, 4, 3, 16, ZSTD_btopt }, /* level 15.*/
{ 18, 19, 18, 6, 3, 32, ZSTD_btopt }, /* level 16.*/
{ 18, 19, 18, 8, 3, 64, ZSTD_btopt }, /* level 17.*/
{ 18, 19, 18, 9, 3,128, ZSTD_btopt }, /* level 18.*/
{ 18, 19, 18, 10, 3,256, ZSTD_btopt }, /* level 19.*/
{ 18, 19, 18, 11, 3,512, ZSTD_btultra }, /* level 20.*/
{ 18, 19, 18, 12, 3,512, ZSTD_btultra }, /* level 21.*/
{ 18, 19, 18, 13, 3,512, ZSTD_btultra }, /* level 22.*/
},
{ /* for srcSize <= 128 KB */
/* W, C, H, S, L, T, strat */
{ 17, 12, 12, 1, 7, 8, ZSTD_fast }, /* level 0 - not used */
{ 17, 12, 13, 1, 6, 8, ZSTD_fast }, /* level 1 */
{ 17, 13, 16, 1, 5, 8, ZSTD_fast }, /* level 2 */
{ 17, 16, 16, 2, 5, 8, ZSTD_dfast }, /* level 3 */
{ 17, 13, 15, 3, 4, 8, ZSTD_greedy }, /* level 4 */
{ 17, 15, 17, 4, 4, 8, ZSTD_greedy }, /* level 5 */
{ 17, 16, 17, 3, 4, 8, ZSTD_lazy }, /* level 6 */
{ 17, 15, 17, 4, 4, 8, ZSTD_lazy2 }, /* level 7 */
{ 17, 17, 17, 4, 4, 8, ZSTD_lazy2 }, /* level 8 */
{ 17, 17, 17, 5, 4, 8, ZSTD_lazy2 }, /* level 9 */
{ 17, 17, 17, 6, 4, 8, ZSTD_lazy2 }, /* level 10 */
{ 17, 17, 17, 7, 4, 8, ZSTD_lazy2 }, /* level 11 */
{ 17, 17, 17, 8, 4, 8, ZSTD_lazy2 }, /* level 12 */
{ 17, 18, 17, 6, 4, 8, ZSTD_btlazy2 }, /* level 13.*/
{ 17, 17, 17, 7, 3, 8, ZSTD_btopt }, /* level 14.*/
{ 17, 17, 17, 7, 3, 16, ZSTD_btopt }, /* level 15.*/
{ 17, 18, 17, 7, 3, 32, ZSTD_btopt }, /* level 16.*/
{ 17, 18, 17, 7, 3, 64, ZSTD_btopt }, /* level 17.*/
{ 17, 18, 17, 7, 3,256, ZSTD_btopt }, /* level 18.*/
{ 17, 18, 17, 8, 3,256, ZSTD_btopt }, /* level 19.*/
{ 17, 18, 17, 9, 3,256, ZSTD_btultra }, /* level 20.*/
{ 17, 18, 17, 10, 3,256, ZSTD_btultra }, /* level 21.*/
{ 17, 18, 17, 11, 3,512, ZSTD_btultra }, /* level 22.*/
},
{ /* for srcSize <= 16 KB */
/* W, C, H, S, L, T, strat */
{ 14, 12, 12, 1, 7, 6, ZSTD_fast }, /* level 0 - not used */
{ 14, 14, 14, 1, 6, 6, ZSTD_fast }, /* level 1 */
{ 14, 14, 14, 1, 4, 6, ZSTD_fast }, /* level 2 */
{ 14, 14, 14, 1, 4, 6, ZSTD_dfast }, /* level 3.*/
{ 14, 14, 14, 4, 4, 6, ZSTD_greedy }, /* level 4.*/
{ 14, 14, 14, 3, 4, 6, ZSTD_lazy }, /* level 5.*/
{ 14, 14, 14, 4, 4, 6, ZSTD_lazy2 }, /* level 6 */
{ 14, 14, 14, 5, 4, 6, ZSTD_lazy2 }, /* level 7 */
{ 14, 14, 14, 6, 4, 6, ZSTD_lazy2 }, /* level 8.*/
{ 14, 15, 14, 6, 4, 6, ZSTD_btlazy2 }, /* level 9.*/
{ 14, 15, 14, 3, 3, 6, ZSTD_btopt }, /* level 10.*/
{ 14, 15, 14, 6, 3, 8, ZSTD_btopt }, /* level 11.*/
{ 14, 15, 14, 6, 3, 16, ZSTD_btopt }, /* level 12.*/
{ 14, 15, 14, 6, 3, 24, ZSTD_btopt }, /* level 13.*/
{ 14, 15, 15, 6, 3, 48, ZSTD_btopt }, /* level 14.*/
{ 14, 15, 15, 6, 3, 64, ZSTD_btopt }, /* level 15.*/
{ 14, 15, 15, 6, 3, 96, ZSTD_btopt }, /* level 16.*/
{ 14, 15, 15, 6, 3,128, ZSTD_btopt }, /* level 17.*/
{ 14, 15, 15, 6, 3,256, ZSTD_btopt }, /* level 18.*/
{ 14, 15, 15, 7, 3,256, ZSTD_btopt }, /* level 19.*/
{ 14, 15, 15, 8, 3,256, ZSTD_btultra }, /* level 20.*/
{ 14, 15, 15, 9, 3,256, ZSTD_btultra }, /* level 21.*/
{ 14, 15, 15, 10, 3,256, ZSTD_btultra }, /* level 22.*/
},
};
#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
/* This function just controls
* the monotonic memory budget increase of ZSTD_defaultCParameters[0].
* Run once, on first ZSTD_getCParams() usage, if ZSTD_DEBUG is enabled
*/
MEM_STATIC void ZSTD_check_compressionLevel_monotonicIncrease_memoryBudget(void)
{
int level;
for (level=1; level<ZSTD_maxCLevel(); level++) {
ZSTD_compressionParameters const c1 = ZSTD_defaultCParameters[0][level];
ZSTD_compressionParameters const c2 = ZSTD_defaultCParameters[0][level+1];
assert(c1.windowLog <= c2.windowLog);
# define ZSTD_TABLECOST(h,c) ((1<<(h)) + (1<<(c)))
assert(ZSTD_TABLECOST(c1.hashLog, c1.chainLog) <= ZSTD_TABLECOST(c2.hashLog, c2.chainLog));
}
}
#endif
/*! ZSTD_getCParams() :
* @return ZSTD_compressionParameters structure for a selected compression level, `srcSize` and `dictSize`.
* Size values are optional, provide 0 if not known or unused */
ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long srcSizeHint, size_t dictSize)
{
size_t const addedSize = srcSizeHint ? 0 : 500;
U64 const rSize = srcSizeHint+dictSize ? srcSizeHint+dictSize+addedSize : (U64)-1;
U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB); /* intentional underflow for srcSizeHint == 0 */
#if defined(ZSTD_DEBUG) && (ZSTD_DEBUG>=1)
static int g_monotonicTest = 1;
if (g_monotonicTest) {
ZSTD_check_compressionLevel_monotonicIncrease_memoryBudget();
g_monotonicTest=0;
}
#endif
if (compressionLevel <= 0) compressionLevel = ZSTD_CLEVEL_DEFAULT; /* 0 == default; no negative compressionLevel yet */
if (compressionLevel > ZSTD_MAX_CLEVEL) compressionLevel = ZSTD_MAX_CLEVEL;
{ ZSTD_compressionParameters const cp = ZSTD_defaultCParameters[tableID][compressionLevel];
return ZSTD_adjustCParams_internal(cp, srcSizeHint, dictSize); }
}
/*! ZSTD_getParams() :
* same as ZSTD_getCParams(), but @return a `ZSTD_parameters` object (instead of `ZSTD_compressionParameters`).
* All fields of `ZSTD_frameParameters` are set to default (0) */
ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long srcSizeHint, size_t dictSize) {
ZSTD_parameters params;
ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSizeHint, dictSize);
memset(&params, 0, sizeof(params));
params.cParams = cParams;
return params;
}
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