2910 lines
126 KiB
C
2910 lines
126 KiB
C
/*
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ZSTD HC - High Compression Mode of Zstandard
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Copyright (C) 2015-2016, Yann Collet.
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BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are
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met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above
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copyright notice, this list of conditions and the following disclaimer
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in the documentation and/or other materials provided with the
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distribution.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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You can contact the author at :
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- Zstd source repository : https://www.zstd.net
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*/
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/* *******************************************************
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* Compiler specifics
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*********************************************************/
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#ifdef _MSC_VER /* Visual Studio */
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# define FORCE_INLINE static __forceinline
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# include <intrin.h> /* For Visual 2005 */
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# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
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#else
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# ifdef __GNUC__
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# define FORCE_INLINE static inline __attribute__((always_inline))
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# else
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# define FORCE_INLINE static inline
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# endif
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#endif
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/*-*************************************
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* Dependencies
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***************************************/
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#include <string.h> /* memset */
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#include "mem.h"
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#define XXH_STATIC_LINKING_ONLY /* XXH64_state_t */
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#include "xxhash.h" /* XXH_reset, update, digest */
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#define FSE_STATIC_LINKING_ONLY
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#include "fse.h"
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#define HUF_STATIC_LINKING_ONLY
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#include "huf.h"
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#include "zstd_internal.h" /* includes zstd.h */
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/*-*************************************
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* Constants
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***************************************/
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static const U32 g_searchStrength = 8; /* control skip over incompressible data */
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/*-*************************************
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* Helper functions
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***************************************/
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size_t ZSTD_compressBound(size_t srcSize) { return FSE_compressBound(srcSize) + 12; }
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/*-*************************************
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* Sequence storage
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***************************************/
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static void ZSTD_resetSeqStore(seqStore_t* ssPtr)
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{
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ssPtr->offset = ssPtr->offsetStart;
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ssPtr->lit = ssPtr->litStart;
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ssPtr->litLength = ssPtr->litLengthStart;
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ssPtr->matchLength = ssPtr->matchLengthStart;
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ssPtr->longLengthID = 0;
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}
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/*-*************************************
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* Context memory management
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***************************************/
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struct ZSTD_CCtx_s
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{
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const BYTE* nextSrc; /* next block here to continue on current prefix */
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const BYTE* base; /* All regular indexes relative to this position */
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const BYTE* dictBase; /* extDict indexes relative to this position */
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U32 dictLimit; /* below that point, need extDict */
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U32 lowLimit; /* below that point, no more data */
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U32 nextToUpdate; /* index from which to continue dictionary update */
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U32 nextToUpdate3; /* index from which to continue dictionary update */
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U32 hashLog3; /* dispatch table : larger == faster, more memory */
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U32 loadedDictEnd;
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U32 stage; /* 0: created; 1: init,dictLoad; 2:started */
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U32 rep[ZSTD_REP_NUM];
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U32 savedRep[ZSTD_REP_NUM];
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U32 dictID;
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ZSTD_parameters params;
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void* workSpace;
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size_t workSpaceSize;
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size_t blockSize;
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U64 frameContentSize;
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XXH64_state_t xxhState;
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ZSTD_customMem customMem;
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seqStore_t seqStore; /* sequences storage ptrs */
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U32* hashTable;
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U32* hashTable3;
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U32* chainTable;
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HUF_CElt* hufTable;
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U32 flagStaticTables;
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FSE_CTable offcodeCTable [FSE_CTABLE_SIZE_U32(OffFSELog, MaxOff)];
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FSE_CTable matchlengthCTable [FSE_CTABLE_SIZE_U32(MLFSELog, MaxML)];
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FSE_CTable litlengthCTable [FSE_CTABLE_SIZE_U32(LLFSELog, MaxLL)];
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};
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ZSTD_CCtx* ZSTD_createCCtx(void)
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{
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return ZSTD_createCCtx_advanced(defaultCustomMem);
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}
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ZSTD_CCtx* ZSTD_createCCtx_advanced(ZSTD_customMem customMem)
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{
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ZSTD_CCtx* cctx;
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if (!customMem.customAlloc && !customMem.customFree)
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customMem = defaultCustomMem;
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if (!customMem.customAlloc || !customMem.customFree)
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return NULL;
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cctx = (ZSTD_CCtx*) customMem.customAlloc(customMem.opaque, sizeof(ZSTD_CCtx));
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if (!cctx) return NULL;
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memset(cctx, 0, sizeof(ZSTD_CCtx));
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memcpy(&(cctx->customMem), &customMem, sizeof(ZSTD_customMem));
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return cctx;
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}
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size_t ZSTD_freeCCtx(ZSTD_CCtx* cctx)
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{
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if (cctx==NULL) return 0; /* support free on NULL */
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if (cctx->workSpace) cctx->customMem.customFree(cctx->customMem.opaque, cctx->workSpace);
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cctx->customMem.customFree(cctx->customMem.opaque, cctx);
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return 0; /* reserved as a potential error code in the future */
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}
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size_t ZSTD_sizeofCCtx(const ZSTD_CCtx* cctx)
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{
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return sizeof(*cctx) + cctx->workSpaceSize;
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}
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const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx) /* hidden interface */
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{
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return &(ctx->seqStore);
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}
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#define CLAMP(val,min,max) { if (val<min) val=min; else if (val>max) val=max; }
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#define CLAMPCHECK(val,min,max) { if ((val<min) || (val>max)) return ERROR(compressionParameter_unsupported); }
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/** ZSTD_checkParams() :
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ensure param values remain within authorized range.
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@return : 0, or an error code if one value is beyond authorized range */
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size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams)
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{
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CLAMPCHECK(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX);
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CLAMPCHECK(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX);
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CLAMPCHECK(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
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CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
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{ U32 const searchLengthMin = (cParams.strategy == ZSTD_fast || cParams.strategy == ZSTD_greedy) ? ZSTD_SEARCHLENGTH_MIN+1 : ZSTD_SEARCHLENGTH_MIN;
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U32 const searchLengthMax = (cParams.strategy == ZSTD_fast) ? ZSTD_SEARCHLENGTH_MAX : ZSTD_SEARCHLENGTH_MAX-1;
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CLAMPCHECK(cParams.searchLength, searchLengthMin, searchLengthMax); }
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CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
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if ((U32)(cParams.strategy) > (U32)ZSTD_btopt) return ERROR(compressionParameter_unsupported);
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return 0;
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}
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/** ZSTD_checkCParams_advanced() :
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temporary work-around, while the compressor compatibility remains limited regarding windowLog < 18 */
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size_t ZSTD_checkCParams_advanced(ZSTD_compressionParameters cParams, U64 srcSize)
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{
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if (srcSize > (1ULL << ZSTD_WINDOWLOG_MIN)) return ZSTD_checkCParams(cParams);
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if (cParams.windowLog < ZSTD_WINDOWLOG_ABSOLUTEMIN) return ERROR(compressionParameter_unsupported);
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if (srcSize <= (1ULL << cParams.windowLog)) cParams.windowLog = ZSTD_WINDOWLOG_MIN; /* fake value - temporary work around */
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if (srcSize <= (1ULL << cParams.chainLog)) cParams.chainLog = ZSTD_CHAINLOG_MIN; /* fake value - temporary work around */
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if ((srcSize <= (1ULL << cParams.hashLog)) && ((U32)cParams.strategy < (U32)ZSTD_btlazy2)) cParams.hashLog = ZSTD_HASHLOG_MIN; /* fake value - temporary work around */
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return ZSTD_checkCParams(cParams);
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}
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/** ZSTD_adjustCParams() :
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optimize cPar for a given input (`srcSize` and `dictSize`).
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mostly downsizing to reduce memory consumption and initialization.
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Both `srcSize` and `dictSize` are optional (use 0 if unknown),
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but if both are 0, no optimization can be done.
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Note : cPar is considered validated at this stage. Use ZSTD_checkParams() to ensure that. */
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ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize)
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{
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if (srcSize+dictSize == 0) return cPar; /* no size information available : no adjustment */
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/* resize params, to use less memory when necessary */
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{ U32 const minSrcSize = (srcSize==0) ? 500 : 0;
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U64 const rSize = srcSize + dictSize + minSrcSize;
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if (rSize < ((U64)1<<ZSTD_WINDOWLOG_MAX)) {
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U32 const srcLog = ZSTD_highbit32((U32)(rSize)-1) + 1;
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if (cPar.windowLog > srcLog) cPar.windowLog = srcLog;
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} }
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if (cPar.hashLog > cPar.windowLog) cPar.hashLog = cPar.windowLog;
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{ U32 const btPlus = (cPar.strategy == ZSTD_btlazy2) || (cPar.strategy == ZSTD_btopt);
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U32 const maxChainLog = cPar.windowLog+btPlus;
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if (cPar.chainLog > maxChainLog) cPar.chainLog = maxChainLog; } /* <= ZSTD_CHAINLOG_MAX */
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if (cPar.windowLog < ZSTD_WINDOWLOG_ABSOLUTEMIN) cPar.windowLog = ZSTD_WINDOWLOG_ABSOLUTEMIN; /* required for frame header */
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if ((cPar.hashLog < ZSTD_HASHLOG_MIN) && ( (U32)cPar.strategy >= (U32)ZSTD_btlazy2)) cPar.hashLog = ZSTD_HASHLOG_MIN; /* required to ensure collision resistance in bt */
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return cPar;
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}
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size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams)
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{
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const size_t blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << cParams.windowLog);
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const U32 divider = (cParams.searchLength==3) ? 3 : 4;
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const size_t maxNbSeq = blockSize / divider;
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const size_t tokenSpace = blockSize + 11*maxNbSeq;
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const size_t chainSize = (cParams.strategy == ZSTD_fast) ? 0 : (1 << cParams.chainLog);
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const size_t hSize = ((size_t)1) << cParams.hashLog;
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const U32 hashLog3 = (cParams.searchLength>3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, cParams.windowLog);
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const size_t h3Size = ((size_t)1) << hashLog3;
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const size_t tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
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size_t const optSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
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+ (ZSTD_OPT_NUM+1)*(sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
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size_t const neededSpace = tableSpace + (256*sizeof(U32)) /* huffTable */ + tokenSpace
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+ ((cParams.strategy == ZSTD_btopt) ? optSpace : 0);
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return sizeof(ZSTD_CCtx) + neededSpace;
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}
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/*! ZSTD_resetCCtx_advanced() :
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note : 'params' is expected to be validated */
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static size_t ZSTD_resetCCtx_advanced (ZSTD_CCtx* zc,
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ZSTD_parameters params, U64 frameContentSize,
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U32 reset)
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{ /* note : params considered validated here */
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const size_t blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << params.cParams.windowLog);
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const U32 divider = (params.cParams.searchLength==3) ? 3 : 4;
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const size_t maxNbSeq = blockSize / divider;
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const size_t tokenSpace = blockSize + 11*maxNbSeq;
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const size_t chainSize = (params.cParams.strategy == ZSTD_fast) ? 0 : (1 << params.cParams.chainLog);
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const size_t hSize = ((size_t)1) << params.cParams.hashLog;
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const U32 hashLog3 = (params.cParams.searchLength>3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog);
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const size_t h3Size = ((size_t)1) << hashLog3;
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const size_t tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
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/* Check if workSpace is large enough, alloc a new one if needed */
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{ size_t const optSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
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+ (ZSTD_OPT_NUM+1)*(sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
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size_t const neededSpace = tableSpace + (256*sizeof(U32)) /* huffTable */ + tokenSpace
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+ ((params.cParams.strategy == ZSTD_btopt) ? optSpace : 0);
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if (zc->workSpaceSize < neededSpace) {
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zc->customMem.customFree(zc->customMem.opaque, zc->workSpace);
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zc->workSpace = zc->customMem.customAlloc(zc->customMem.opaque, neededSpace);
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if (zc->workSpace == NULL) return ERROR(memory_allocation);
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zc->workSpaceSize = neededSpace;
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} }
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if (reset) memset(zc->workSpace, 0, tableSpace ); /* reset only tables */
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XXH64_reset(&zc->xxhState, 0);
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zc->hashLog3 = hashLog3;
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zc->hashTable = (U32*)(zc->workSpace);
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zc->chainTable = zc->hashTable + hSize;
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zc->hashTable3 = zc->chainTable + chainSize;
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zc->seqStore.buffer = zc->hashTable3 + h3Size;
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zc->hufTable = (HUF_CElt*)zc->seqStore.buffer;
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zc->flagStaticTables = 0;
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zc->seqStore.buffer = ((U32*)(zc->seqStore.buffer)) + 256; /* note : HUF_CElt* is incomplete type, size is simulated using U32 */
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zc->nextToUpdate = 1;
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zc->nextSrc = NULL;
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zc->base = NULL;
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zc->dictBase = NULL;
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zc->dictLimit = 0;
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zc->lowLimit = 0;
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zc->params = params;
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zc->blockSize = blockSize;
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zc->frameContentSize = frameContentSize;
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{ int i; for (i=0; i<ZSTD_REP_NUM; i++) zc->rep[i] = repStartValue[i]; }
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if (params.cParams.strategy == ZSTD_btopt) {
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zc->seqStore.litFreq = (U32*)(zc->seqStore.buffer);
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zc->seqStore.litLengthFreq = zc->seqStore.litFreq + (1<<Litbits);
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zc->seqStore.matchLengthFreq = zc->seqStore.litLengthFreq + (MaxLL+1);
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zc->seqStore.offCodeFreq = zc->seqStore.matchLengthFreq + (MaxML+1);
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zc->seqStore.buffer = zc->seqStore.offCodeFreq + (MaxOff+1);
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zc->seqStore.matchTable = (ZSTD_match_t*)zc->seqStore.buffer;
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zc->seqStore.buffer = zc->seqStore.matchTable + ZSTD_OPT_NUM+1;
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zc->seqStore.priceTable = (ZSTD_optimal_t*)zc->seqStore.buffer;
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zc->seqStore.buffer = zc->seqStore.priceTable + ZSTD_OPT_NUM+1;
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zc->seqStore.litLengthSum = 0;
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}
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zc->seqStore.offsetStart = (U32*)(zc->seqStore.buffer);
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zc->seqStore.buffer = zc->seqStore.offsetStart + maxNbSeq;
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zc->seqStore.litLengthStart = (U16*)zc->seqStore.buffer;
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zc->seqStore.matchLengthStart = zc->seqStore.litLengthStart + maxNbSeq;
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zc->seqStore.llCodeStart = (BYTE*) (zc->seqStore.matchLengthStart + maxNbSeq);
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zc->seqStore.mlCodeStart = zc->seqStore.llCodeStart + maxNbSeq;
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zc->seqStore.offCodeStart = zc->seqStore.mlCodeStart + maxNbSeq;
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zc->seqStore.litStart = zc->seqStore.offCodeStart + maxNbSeq;
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zc->stage = 1;
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zc->dictID = 0;
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zc->loadedDictEnd = 0;
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return 0;
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}
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/*! ZSTD_copyCCtx() :
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* Duplicate an existing context `srcCCtx` into another one `dstCCtx`.
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* Only works during stage 1 (i.e. after creation, but before first call to ZSTD_compressContinue()).
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* @return : 0, or an error code */
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size_t ZSTD_copyCCtx(ZSTD_CCtx* dstCCtx, const ZSTD_CCtx* srcCCtx)
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{
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if (srcCCtx->stage!=1) return ERROR(stage_wrong);
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memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem));
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ZSTD_resetCCtx_advanced(dstCCtx, srcCCtx->params, srcCCtx->frameContentSize, 0);
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dstCCtx->params.fParams.contentSizeFlag = 0; /* content size different from the one set during srcCCtx init */
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/* copy tables */
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{ const size_t chainSize = (srcCCtx->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->params.cParams.chainLog);
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const size_t hSize = ((size_t)1) << srcCCtx->params.cParams.hashLog;
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const size_t h3Size = (size_t)1 << srcCCtx->hashLog3;
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const size_t tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
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memcpy(dstCCtx->workSpace, srcCCtx->workSpace, tableSpace);
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}
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/* copy dictionary offsets */
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dstCCtx->nextToUpdate = srcCCtx->nextToUpdate;
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dstCCtx->nextToUpdate3= srcCCtx->nextToUpdate3;
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dstCCtx->nextSrc = srcCCtx->nextSrc;
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dstCCtx->base = srcCCtx->base;
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dstCCtx->dictBase = srcCCtx->dictBase;
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dstCCtx->dictLimit = srcCCtx->dictLimit;
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dstCCtx->lowLimit = srcCCtx->lowLimit;
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dstCCtx->loadedDictEnd= srcCCtx->loadedDictEnd;
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dstCCtx->dictID = srcCCtx->dictID;
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/* copy entropy tables */
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dstCCtx->flagStaticTables = srcCCtx->flagStaticTables;
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if (srcCCtx->flagStaticTables) {
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memcpy(dstCCtx->hufTable, srcCCtx->hufTable, 256*4);
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memcpy(dstCCtx->litlengthCTable, srcCCtx->litlengthCTable, sizeof(dstCCtx->litlengthCTable));
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memcpy(dstCCtx->matchlengthCTable, srcCCtx->matchlengthCTable, sizeof(dstCCtx->matchlengthCTable));
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memcpy(dstCCtx->offcodeCTable, srcCCtx->offcodeCTable, sizeof(dstCCtx->offcodeCTable));
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}
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return 0;
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}
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/*! ZSTD_reduceTable() :
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* reduce table indexes by `reducerValue` */
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static void ZSTD_reduceTable (U32* const table, U32 const size, U32 const reducerValue)
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{
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U32 u;
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for (u=0 ; u < size ; u++) {
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if (table[u] < reducerValue) table[u] = 0;
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else table[u] -= reducerValue;
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}
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}
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/*! ZSTD_reduceIndex() :
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* rescale all indexes to avoid future overflow (indexes are U32) */
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static void ZSTD_reduceIndex (ZSTD_CCtx* zc, const U32 reducerValue)
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{
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{ const U32 hSize = 1 << zc->params.cParams.hashLog;
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ZSTD_reduceTable(zc->hashTable, hSize, reducerValue); }
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{ const U32 chainSize = (zc->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->params.cParams.chainLog);
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ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue); }
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|
|
{ const U32 h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0;
|
|
ZSTD_reduceTable(zc->hashTable3, h3Size, reducerValue); }
|
|
}
|
|
|
|
|
|
/*-*******************************************************
|
|
* Block entropic compression
|
|
*********************************************************/
|
|
|
|
/* See 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;
|
|
default: /*note : should not be necessary : flSize is within {1,2,3} */
|
|
case 3: /* 2 - 2 - 20 */
|
|
MEM_writeLE32(ostart, (U32)((U32)set_basic + (3<<2) + (srcSize<<4)));
|
|
break;
|
|
}
|
|
|
|
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;
|
|
default: /*note : should not be necessary : flSize is necessarily within {1,2,3} */
|
|
case 3: /* 2 - 2 - 20 */
|
|
MEM_writeLE32(ostart, (U32)((U32)set_rle + (3<<2) + (srcSize<<4)));
|
|
break;
|
|
}
|
|
|
|
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->flagStaticTables ? 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 */
|
|
if (zc->flagStaticTables && (lhSize==3)) {
|
|
hType = set_repeat;
|
|
singleStream = 1;
|
|
cLitSize = HUF_compress1X_usingCTable(ostart+lhSize, dstCapacity-lhSize, src, srcSize, zc->hufTable);
|
|
} else {
|
|
cLitSize = singleStream ? HUF_compress1X(ostart+lhSize, dstCapacity-lhSize, src, srcSize, 255, 11)
|
|
: HUF_compress2 (ostart+lhSize, dstCapacity-lhSize, src, srcSize, 255, 11);
|
|
}
|
|
|
|
if ((cLitSize==0) | (cLitSize >= srcSize - minGain))
|
|
return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize);
|
|
if (cLitSize==1)
|
|
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;
|
|
}
|
|
default: /* should not be necessary, lhSize is only {3,4,5} */
|
|
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;
|
|
}
|
|
}
|
|
return lhSize+cLitSize;
|
|
}
|
|
|
|
|
|
void ZSTD_seqToCodes(const seqStore_t* seqStorePtr, size_t const nbSeq)
|
|
{
|
|
/* LL codes */
|
|
{ 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 };
|
|
const BYTE LL_deltaCode = 19;
|
|
const U16* const llTable = seqStorePtr->litLengthStart;
|
|
BYTE* const llCodeTable = seqStorePtr->llCodeStart;
|
|
size_t u;
|
|
for (u=0; u<nbSeq; u++) {
|
|
U32 const ll = llTable[u];
|
|
llCodeTable[u] = (ll>63) ? (BYTE)ZSTD_highbit32(ll) + LL_deltaCode : LL_Code[ll];
|
|
}
|
|
if (seqStorePtr->longLengthID==1)
|
|
llCodeTable[seqStorePtr->longLengthPos] = MaxLL;
|
|
}
|
|
|
|
/* Offset codes */
|
|
{ const U32* const offsetTable = seqStorePtr->offsetStart;
|
|
BYTE* const ofCodeTable = seqStorePtr->offCodeStart;
|
|
size_t u;
|
|
for (u=0; u<nbSeq; u++) ofCodeTable[u] = (BYTE)ZSTD_highbit32(offsetTable[u]);
|
|
}
|
|
|
|
/* ML codes */
|
|
{ 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 };
|
|
const BYTE ML_deltaCode = 36;
|
|
const U16* const mlTable = seqStorePtr->matchLengthStart;
|
|
BYTE* const mlCodeTable = seqStorePtr->mlCodeStart;
|
|
size_t u;
|
|
for (u=0; u<nbSeq; u++) {
|
|
U32 const ml = mlTable[u];
|
|
mlCodeTable[u] = (ml>127) ? (BYTE)ZSTD_highbit32(ml) + ML_deltaCode : ML_Code[ml];
|
|
}
|
|
if (seqStorePtr->longLengthID==2)
|
|
mlCodeTable[seqStorePtr->longLengthPos] = MaxML;
|
|
}
|
|
}
|
|
|
|
|
|
size_t ZSTD_compressSequences(ZSTD_CCtx* zc,
|
|
void* dst, size_t dstCapacity,
|
|
size_t srcSize)
|
|
{
|
|
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 */
|
|
U16* const llTable = seqStorePtr->litLengthStart;
|
|
U16* const mlTable = seqStorePtr->matchLengthStart;
|
|
const U32* const offsetTable = seqStorePtr->offsetStart;
|
|
const U32* const offsetTableEnd = seqStorePtr->offset;
|
|
BYTE* const ofCodeTable = seqStorePtr->offCodeStart;
|
|
BYTE* const llCodeTable = seqStorePtr->llCodeStart;
|
|
BYTE* const mlCodeTable = seqStorePtr->mlCodeStart;
|
|
BYTE* const ostart = (BYTE*)dst;
|
|
BYTE* const oend = ostart + dstCapacity;
|
|
BYTE* op = ostart;
|
|
size_t const nbSeq = offsetTableEnd - offsetTable;
|
|
BYTE* seqHead;
|
|
|
|
/* 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, nbSeq);
|
|
|
|
/* CTable for Literal Lengths */
|
|
{ U32 max = MaxLL;
|
|
size_t const mostFrequent = FSE_countFast(count, &max, llCodeTable, nbSeq);
|
|
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
|
|
*op++ = llCodeTable[0];
|
|
FSE_buildCTable_rle(CTable_LitLength, (BYTE)max);
|
|
LLtype = set_rle;
|
|
} else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
|
|
LLtype = set_repeat;
|
|
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (LL_defaultNormLog-1)))) {
|
|
FSE_buildCTable(CTable_LitLength, LL_defaultNorm, MaxLL, LL_defaultNormLog);
|
|
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 ERROR(GENERIC);
|
|
op += NCountSize; }
|
|
FSE_buildCTable(CTable_LitLength, norm, max, tableLog);
|
|
LLtype = set_compressed;
|
|
} }
|
|
|
|
/* CTable for Offsets */
|
|
{ U32 max = MaxOff;
|
|
size_t const mostFrequent = FSE_countFast(count, &max, ofCodeTable, nbSeq);
|
|
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
|
|
*op++ = ofCodeTable[0];
|
|
FSE_buildCTable_rle(CTable_OffsetBits, (BYTE)max);
|
|
Offtype = set_rle;
|
|
} else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
|
|
Offtype = set_repeat;
|
|
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (OF_defaultNormLog-1)))) {
|
|
FSE_buildCTable(CTable_OffsetBits, OF_defaultNorm, MaxOff, OF_defaultNormLog);
|
|
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 ERROR(GENERIC);
|
|
op += NCountSize; }
|
|
FSE_buildCTable(CTable_OffsetBits, norm, max, tableLog);
|
|
Offtype = set_compressed;
|
|
} }
|
|
|
|
/* CTable for MatchLengths */
|
|
{ U32 max = MaxML;
|
|
size_t const mostFrequent = FSE_countFast(count, &max, mlCodeTable, nbSeq);
|
|
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
|
|
*op++ = *mlCodeTable;
|
|
FSE_buildCTable_rle(CTable_MatchLength, (BYTE)max);
|
|
MLtype = set_rle;
|
|
} else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
|
|
MLtype = set_repeat;
|
|
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (ML_defaultNormLog-1)))) {
|
|
FSE_buildCTable(CTable_MatchLength, ML_defaultNorm, MaxML, ML_defaultNormLog);
|
|
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 ERROR(GENERIC);
|
|
op += NCountSize; }
|
|
FSE_buildCTable(CTable_MatchLength, norm, max, tableLog);
|
|
MLtype = set_compressed;
|
|
} }
|
|
|
|
*seqHead = (BYTE)((LLtype<<6) + (Offtype<<4) + (MLtype<<2));
|
|
zc->flagStaticTables = 0;
|
|
|
|
/* Encoding Sequences */
|
|
{ BIT_CStream_t blockStream;
|
|
FSE_CState_t stateMatchLength;
|
|
FSE_CState_t stateOffsetBits;
|
|
FSE_CState_t stateLitLength;
|
|
|
|
{ size_t const errorCode = BIT_initCStream(&blockStream, op, oend-op);
|
|
if (ERR_isError(errorCode)) return ERROR(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, llTable[nbSeq-1], LL_bits[llCodeTable[nbSeq-1]]);
|
|
if (MEM_32bits()) BIT_flushBits(&blockStream);
|
|
BIT_addBits(&blockStream, mlTable[nbSeq-1], ML_bits[mlCodeTable[nbSeq-1]]);
|
|
if (MEM_32bits()) BIT_flushBits(&blockStream);
|
|
BIT_addBits(&blockStream, offsetTable[nbSeq-1], ofCodeTable[nbSeq-1]);
|
|
BIT_flushBits(&blockStream);
|
|
|
|
{ size_t n;
|
|
for (n=nbSeq-2 ; n<nbSeq ; n--) { /* intentional underflow */
|
|
const BYTE ofCode = ofCodeTable[n];
|
|
const BYTE mlCode = mlCodeTable[n];
|
|
const BYTE llCode = llCodeTable[n];
|
|
const U32 llBits = LL_bits[llCode];
|
|
const U32 mlBits = ML_bits[mlCode];
|
|
const U32 ofBits = ofCode; /* 32b*/ /* 64b*/
|
|
/* (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, llTable[n], llBits);
|
|
if (MEM_32bits() && ((llBits+mlBits)>24)) BIT_flushBits(&blockStream);
|
|
BIT_addBits(&blockStream, mlTable[n], mlBits);
|
|
if (MEM_32bits()) BIT_flushBits(&blockStream); /* (7)*/
|
|
BIT_addBits(&blockStream, offsetTable[n], 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) return 0; }
|
|
|
|
/* confirm repcodes */
|
|
{ int i; for (i=0; i<ZSTD_REP_NUM; i++) zc->rep[i] = zc->savedRep[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 0 /* for debug */
|
|
static const BYTE* g_start = NULL;
|
|
const U32 pos = (U32)(literals - g_start);
|
|
if (g_start==NULL) g_start = literals;
|
|
//if ((pos > 1) && (pos < 50000))
|
|
printf("Cpos %6u :%5u literals & match %3u bytes at distance %6u \n",
|
|
pos, (U32)litLength, (U32)matchCode+MINMATCH, (U32)offsetCode);
|
|
#endif
|
|
ZSTD_statsUpdatePrices(&seqStorePtr->stats, litLength, (const BYTE*)literals, offsetCode, matchCode); /* debug only */
|
|
|
|
/* copy Literals */
|
|
ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);
|
|
seqStorePtr->lit += litLength;
|
|
|
|
/* literal Length */
|
|
if (litLength>0xFFFF) { seqStorePtr->longLengthID = 1; seqStorePtr->longLengthPos = (U32)(seqStorePtr->litLength - seqStorePtr->litLengthStart); }
|
|
*seqStorePtr->litLength++ = (U16)litLength;
|
|
|
|
/* match offset */
|
|
*(seqStorePtr->offset++) = offsetCode + 1;
|
|
|
|
/* match Length */
|
|
if (matchCode>0xFFFF) { seqStorePtr->longLengthID = 2; seqStorePtr->longLengthPos = (U32)(seqStorePtr->matchLength - seqStorePtr->matchLengthStart); }
|
|
*seqStorePtr->matchLength++ = (U16)matchCode;
|
|
}
|
|
|
|
|
|
/*-*************************************
|
|
* 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 matchLength = ZSTD_count(ip, match, vEnd);
|
|
if (match + matchLength == mEnd)
|
|
matchLength += ZSTD_count(ip+matchLength, iStart, iEnd);
|
|
return matchLength;
|
|
}
|
|
|
|
|
|
/*-*************************************
|
|
* 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 = 58295818150454627ULL;
|
|
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;
|
|
const U32 hBits = zc->params.cParams.hashLog;
|
|
const BYTE* const base = zc->base;
|
|
const BYTE* ip = base + zc->nextToUpdate;
|
|
const BYTE* const iend = ((const BYTE*)end) - 8;
|
|
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;
|
|
const U32 hBits = cctx->params.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 - 8;
|
|
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))) { /* note : by construction, offset_1 <= current */
|
|
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->savedRep[0] = offset_1 ? offset_1 : offsetSaved;
|
|
cctx->savedRep[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->params.cParams.searchLength;
|
|
switch(mls)
|
|
{
|
|
default:
|
|
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->params.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+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repMatchEnd, lowPrefixPtr) + EQUAL_READ32;
|
|
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+EQUAL_READ32, match+EQUAL_READ32, iend, matchEnd, lowPrefixPtr) + EQUAL_READ32;
|
|
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 repLength2 = ZSTD_count_2segments(ip+EQUAL_READ32, repMatch2+EQUAL_READ32, iend, repEnd2, lowPrefixPtr) + EQUAL_READ32;
|
|
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->savedRep[0] = offset_1; ctx->savedRep[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)
|
|
{
|
|
const U32 mls = ctx->params.cParams.searchLength;
|
|
switch(mls)
|
|
{
|
|
default:
|
|
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;
|
|
const U32 hBitsL = cctx->params.cParams.hashLog;
|
|
U32* const hashSmall = cctx->chainTable;
|
|
const U32 hBitsS = cctx->params.cParams.chainLog;
|
|
const BYTE* const base = cctx->base;
|
|
const BYTE* ip = base + cctx->nextToUpdate;
|
|
const BYTE* const iend = ((const BYTE*)end) - 8;
|
|
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->params.cParams.hashLog;
|
|
U32* const hashSmall = cctx->chainTable;
|
|
const U32 hBitsS = cctx->params.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 - 8;
|
|
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 */
|
|
|
|
if ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1))) { /* note : by construction, offset_1 <= current */
|
|
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)) ) {
|
|
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->savedRep[0] = offset_1 ? offset_1 : offsetSaved;
|
|
cctx->savedRep[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->params.cParams.searchLength;
|
|
switch(mls)
|
|
{
|
|
default:
|
|
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;
|
|
const U32 hBitsL = ctx->params.cParams.hashLog;
|
|
U32* const hashSmall = ctx->chainTable;
|
|
const U32 hBitsS = ctx->params.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))) {
|
|
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);
|
|
} 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+EQUAL_READ32, repMatch2+EQUAL_READ32, iend, repEnd2, lowPrefixPtr) + EQUAL_READ32;
|
|
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->savedRep[0] = offset_1; ctx->savedRep[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)
|
|
{
|
|
const U32 mls = ctx->params.cParams.searchLength;
|
|
switch(mls)
|
|
{
|
|
default:
|
|
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;
|
|
const U32 hashLog = zc->params.cParams.hashLog;
|
|
const size_t h = ZSTD_hashPtr(ip, hashLog, mls);
|
|
U32* const bt = zc->chainTable;
|
|
const U32 btLog = zc->params.cParams.chainLog - 1;
|
|
const U32 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 = base + matchIndex;
|
|
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 */
|
|
const U32 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* 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;
|
|
const U32 hashLog = zc->params.cParams.hashLog;
|
|
const size_t h = ZSTD_hashPtr(ip, hashLog, mls);
|
|
U32* const bt = zc->chainTable;
|
|
const U32 btLog = zc->params.cParams.chainLog - 1;
|
|
const U32 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* 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 :
|
|
case 4 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4);
|
|
case 5 : return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5);
|
|
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 :
|
|
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 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 (ie. 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->params.cParams.hashLog;
|
|
U32* const chainTable = zc->chainTable;
|
|
const U32 chainMask = (1 << zc->params.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)];
|
|
}
|
|
|
|
|
|
|
|
FORCE_INLINE /* inlining is important to hardwire a hot branch (template emulation) */
|
|
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->params.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=EQUAL_READ32-1;
|
|
|
|
/* 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+EQUAL_READ32, match+EQUAL_READ32, iLimit, dictEnd, prefixStart) + EQUAL_READ32;
|
|
}
|
|
|
|
/* save best solution */
|
|
if (currentMl > ml) { ml = currentMl; *offsetPtr = current - matchIndex + ZSTD_REP_MOVE; if (ip+currentMl == iLimit) break; /* best possible, and avoid read overflow*/ }
|
|
|
|
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 :
|
|
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 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 :
|
|
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 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->params.cParams.searchLog;
|
|
U32 const mls = ctx->params.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+EQUAL_READ32, ip+1+EQUAL_READ32-offset_1, iend) + EQUAL_READ32;
|
|
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 < EQUAL_READ32) {
|
|
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+EQUAL_READ32, ip+EQUAL_READ32-offset_1, iend) + EQUAL_READ32;
|
|
int const gain2 = (int)(mlRep * 3);
|
|
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
|
|
if ((mlRep >= EQUAL_READ32) && (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 >= EQUAL_READ32) && (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+EQUAL_READ32, ip+EQUAL_READ32-offset_1, iend) + EQUAL_READ32;
|
|
int const gain2 = (int)(ml2 * 4);
|
|
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
|
|
if ((ml2 >= EQUAL_READ32) && (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 >= EQUAL_READ32) && (gain2 > gain1)) {
|
|
matchLength = ml2, offset = offset2, start = ip;
|
|
continue;
|
|
} } }
|
|
break; /* nothing found : store previous solution */
|
|
}
|
|
|
|
/* catch up */
|
|
if (offset) {
|
|
while ((start>anchor) && (start>base+offset-ZSTD_REP_MOVE) && (start[-1] == start[-1-offset+ZSTD_REP_MOVE])) /* 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+EQUAL_READ32, ip+EQUAL_READ32-offset_2, iend) + EQUAL_READ32;
|
|
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->savedRep[0] = offset_1 ? offset_1 : savedOffset;
|
|
ctx->savedRep[1] = offset_2 ? offset_2 : savedOffset;
|
|
|
|
/* Last Literals */
|
|
{ size_t const lastLLSize = iend - anchor;
|
|
memcpy(seqStorePtr->lit, anchor, lastLLSize);
|
|
seqStorePtr->lit += lastLLSize;
|
|
ZSTD_statsUpdatePrices(&seqStorePtr->stats, lastLLSize, anchor, 0, 0);
|
|
}
|
|
}
|
|
|
|
|
|
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->params.cParams.searchLog;
|
|
const U32 mls = ctx->params.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+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
|
|
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 < EQUAL_READ32) {
|
|
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+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
|
|
int const gain2 = (int)(repLength * 3);
|
|
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
|
|
if ((repLength >= EQUAL_READ32) && (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 >= EQUAL_READ32) && (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 repLength = ZSTD_count_2segments(ip+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
|
|
int gain2 = (int)(repLength * 4);
|
|
int gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
|
|
if ((repLength >= EQUAL_READ32) && (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 >= EQUAL_READ32) && (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+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
|
|
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->savedRep[0] = offset_1; ctx->savedRep[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);
|
|
#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);
|
|
#else
|
|
(void)ctx; (void)src; (void)srcSize;
|
|
return;
|
|
#endif
|
|
}
|
|
|
|
|
|
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][7] = {
|
|
{ ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy, ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2, ZSTD_compressBlock_btlazy2, ZSTD_compressBlock_btopt },
|
|
{ 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 }
|
|
};
|
|
|
|
return blockCompressor[extDict][(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->params.cParams.strategy, zc->lowLimit < zc->dictLimit);
|
|
if (srcSize < MIN_CBLOCK_SIZE+ZSTD_blockHeaderSize+1) return 0; /* don't even attempt compression below a certain srcSize */
|
|
ZSTD_resetSeqStore(&(zc->seqStore));
|
|
blockCompressor(zc, src, srcSize);
|
|
return ZSTD_compressSequences(zc, dst, dstCapacity, srcSize);
|
|
}
|
|
|
|
|
|
|
|
|
|
static size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
size_t blockSize = cctx->blockSize;
|
|
size_t remaining = srcSize;
|
|
const BYTE* ip = (const BYTE*)src;
|
|
BYTE* const ostart = (BYTE*)dst;
|
|
BYTE* op = ostart;
|
|
const U32 maxDist = 1 << cctx->params.cParams.windowLog;
|
|
ZSTD_stats_t* stats = &cctx->seqStore.stats;
|
|
ZSTD_statsInit(stats); /* debug only */
|
|
|
|
if (cctx->params.fParams.checksumFlag)
|
|
XXH64_update(&cctx->xxhState, src, srcSize);
|
|
|
|
while (remaining) {
|
|
size_t cSize;
|
|
ZSTD_statsResetFreqs(stats); /* debug only */
|
|
|
|
if (dstCapacity < ZSTD_blockHeaderSize + MIN_CBLOCK_SIZE) return ERROR(dstSize_tooSmall); /* not enough space to store compressed block */
|
|
if (remaining < blockSize) blockSize = remaining;
|
|
|
|
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 */
|
|
cSize = ZSTD_noCompressBlock(op, dstCapacity, ip, blockSize);
|
|
if (ZSTD_isError(cSize)) return cSize;
|
|
} else {
|
|
U32 const cBlockHeader24 = (U32)bt_compressed + (U32)(cSize << 2);
|
|
MEM_writeLE24(op, cBlockHeader24);
|
|
cSize += 3;
|
|
}
|
|
|
|
remaining -= blockSize;
|
|
dstCapacity -= cSize;
|
|
ip += blockSize;
|
|
op += cSize;
|
|
}
|
|
|
|
ZSTD_statsPrint(stats, cctx->params.cParams.searchLength); /* debug only */
|
|
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 dictIDSizeCode = (dictID>0) + (dictID>=256) + (dictID>=65536); /* 0-3 */
|
|
U32 const checksumFlag = params.fParams.checksumFlag>0;
|
|
U32 const windowSize = 1U << params.cParams.windowLog;
|
|
U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize > (pledgedSrcSize-1));
|
|
BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
|
|
U32 const fcsCode = params.fParams.contentSizeFlag ?
|
|
(pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) : /* 0-3 */
|
|
0;
|
|
BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (singleSegment<<5) + (fcsCode<<6) );
|
|
size_t pos;
|
|
|
|
if (dstCapacity < ZSTD_frameHeaderSize_max) return ERROR(dstSize_tooSmall);
|
|
|
|
MEM_writeLE32(dst, ZSTD_MAGICNUMBER);
|
|
op[4] = frameHeaderDecriptionByte; pos=5;
|
|
if (!singleSegment) op[pos++] = windowLogByte;
|
|
switch(dictIDSizeCode)
|
|
{
|
|
default: /* 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: /* 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* zc,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize,
|
|
U32 frame)
|
|
{
|
|
const BYTE* const ip = (const BYTE*) src;
|
|
size_t fhSize = 0;
|
|
|
|
if (zc->stage==0) return ERROR(stage_wrong);
|
|
if (frame && (zc->stage==1)) { /* copy saved header */
|
|
fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, zc->params, zc->frameContentSize, zc->dictID);
|
|
if (ZSTD_isError(fhSize)) return fhSize;
|
|
dstCapacity -= fhSize;
|
|
dst = (char*)dst + fhSize;
|
|
zc->stage = 2;
|
|
}
|
|
|
|
/* Check if blocks follow each other */
|
|
if (src != zc->nextSrc) {
|
|
/* not contiguous */
|
|
size_t const delta = zc->nextSrc - ip;
|
|
zc->lowLimit = zc->dictLimit;
|
|
zc->dictLimit = (U32)(zc->nextSrc - zc->base);
|
|
zc->dictBase = zc->base;
|
|
zc->base -= delta;
|
|
zc->nextToUpdate = zc->dictLimit;
|
|
if (zc->dictLimit - zc->lowLimit < 8) zc->lowLimit = zc->dictLimit; /* too small extDict */
|
|
}
|
|
|
|
/* preemptive overflow correction */
|
|
if (zc->lowLimit > (1<<30)) {
|
|
U32 const btplus = (zc->params.cParams.strategy == ZSTD_btlazy2) | (zc->params.cParams.strategy == ZSTD_btopt);
|
|
U32 const chainMask = (1 << (zc->params.cParams.chainLog - btplus)) - 1;
|
|
U32 const newLowLimit = zc->lowLimit & chainMask; /* preserve position % chainSize */
|
|
U32 const correction = zc->lowLimit - newLowLimit;
|
|
ZSTD_reduceIndex(zc, correction);
|
|
zc->base += correction;
|
|
zc->dictBase += correction;
|
|
zc->lowLimit = newLowLimit;
|
|
zc->dictLimit -= correction;
|
|
if (zc->nextToUpdate < correction) zc->nextToUpdate = 0;
|
|
else zc->nextToUpdate -= correction;
|
|
}
|
|
|
|
/* if input and dictionary overlap : reduce dictionary (presumed modified by input) */
|
|
if ((ip+srcSize > zc->dictBase + zc->lowLimit) && (ip < zc->dictBase + zc->dictLimit)) {
|
|
zc->lowLimit = (U32)(ip + srcSize - zc->dictBase);
|
|
if (zc->lowLimit > zc->dictLimit) zc->lowLimit = zc->dictLimit;
|
|
}
|
|
|
|
zc->nextSrc = ip + srcSize;
|
|
{ size_t const cSize = frame ?
|
|
ZSTD_compress_generic (zc, dst, dstCapacity, src, srcSize) :
|
|
ZSTD_compressBlock_internal (zc, dst, dstCapacity, src, srcSize);
|
|
if (ZSTD_isError(cSize)) return cSize;
|
|
return cSize + fhSize;
|
|
}
|
|
}
|
|
|
|
|
|
size_t ZSTD_compressContinue (ZSTD_CCtx* zc,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
return ZSTD_compressContinue_internal(zc, dst, dstCapacity, src, srcSize, 1);
|
|
}
|
|
|
|
|
|
size_t ZSTD_getBlockSizeMax(ZSTD_CCtx* cctx)
|
|
{
|
|
return MIN (ZSTD_BLOCKSIZE_ABSOLUTEMAX, 1 << cctx->params.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_getBlockSizeMax(cctx);
|
|
if (srcSize > blockSizeMax) return ERROR(srcSize_wrong);
|
|
ZSTD_LOG_BLOCK("%p: ZSTD_compressBlock searchLength=%d\n", cctx->base, cctx->params.cParams.searchLength);
|
|
return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 0);
|
|
}
|
|
|
|
|
|
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 = (U32)(iend - zc->base);
|
|
|
|
zc->nextSrc = iend;
|
|
if (srcSize <= 8) return 0;
|
|
|
|
switch(zc->params.cParams.strategy)
|
|
{
|
|
case ZSTD_fast:
|
|
ZSTD_fillHashTable (zc, iend, zc->params.cParams.searchLength);
|
|
break;
|
|
|
|
case ZSTD_dfast:
|
|
ZSTD_fillDoubleHashTable (zc, iend, zc->params.cParams.searchLength);
|
|
break;
|
|
|
|
case ZSTD_greedy:
|
|
case ZSTD_lazy:
|
|
case ZSTD_lazy2:
|
|
ZSTD_insertAndFindFirstIndex (zc, iend-8, zc->params.cParams.searchLength);
|
|
break;
|
|
|
|
case ZSTD_btlazy2:
|
|
case ZSTD_btopt:
|
|
ZSTD_updateTree(zc, iend-8, iend, 1 << zc->params.cParams.searchLog, zc->params.cParams.searchLength);
|
|
break;
|
|
|
|
default:
|
|
return ERROR(GENERIC); /* strategy doesn't exist; impossible */
|
|
}
|
|
|
|
zc->nextToUpdate = zc->loadedDictEnd;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Dictionary format :
|
|
Magic == ZSTD_DICT_MAGIC (4 bytes)
|
|
HUF_writeCTable(256)
|
|
FSE_writeNCount(ml)
|
|
FSE_writeNCount(off)
|
|
FSE_writeNCount(ll)
|
|
RepOffsets
|
|
Dictionary content
|
|
*/
|
|
/*! ZSTD_loadDictEntropyStats() :
|
|
@return : size read from dictionary
|
|
note : magic number supposed already checked */
|
|
static size_t ZSTD_loadDictEntropyStats(ZSTD_CCtx* cctx, const void* dict, size_t dictSize)
|
|
{
|
|
const BYTE* dictPtr = (const BYTE*)dict;
|
|
const BYTE* const dictEnd = dictPtr + dictSize;
|
|
|
|
{ size_t const hufHeaderSize = HUF_readCTable(cctx->hufTable, 255, dict, dictSize);
|
|
if (HUF_isError(hufHeaderSize)) return ERROR(dictionary_corrupted);
|
|
dictPtr += hufHeaderSize;
|
|
}
|
|
|
|
{ short offcodeNCount[MaxOff+1];
|
|
unsigned offcodeMaxValue = MaxOff, offcodeLog = OffFSELog;
|
|
size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd-dictPtr);
|
|
if (FSE_isError(offcodeHeaderSize)) return ERROR(dictionary_corrupted);
|
|
{ size_t const errorCode = FSE_buildCTable(cctx->offcodeCTable, offcodeNCount, offcodeMaxValue, offcodeLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted); }
|
|
dictPtr += offcodeHeaderSize;
|
|
}
|
|
|
|
{ short matchlengthNCount[MaxML+1];
|
|
unsigned matchlengthMaxValue = MaxML, matchlengthLog = MLFSELog;
|
|
size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd-dictPtr);
|
|
if (FSE_isError(matchlengthHeaderSize)) return ERROR(dictionary_corrupted);
|
|
{ size_t const errorCode = FSE_buildCTable(cctx->matchlengthCTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted); }
|
|
dictPtr += matchlengthHeaderSize;
|
|
}
|
|
|
|
{ short litlengthNCount[MaxLL+1];
|
|
unsigned litlengthMaxValue = MaxLL, litlengthLog = LLFSELog;
|
|
size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd-dictPtr);
|
|
if (FSE_isError(litlengthHeaderSize)) return ERROR(dictionary_corrupted);
|
|
{ size_t const errorCode = FSE_buildCTable(cctx->litlengthCTable, litlengthNCount, litlengthMaxValue, litlengthLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted); }
|
|
dictPtr += litlengthHeaderSize;
|
|
}
|
|
|
|
if (dictPtr+12 > dictEnd) return ERROR(dictionary_corrupted);
|
|
cctx->rep[0] = MEM_readLE32(dictPtr+0); if (cctx->rep[0] >= dictSize) return ERROR(dictionary_corrupted);
|
|
cctx->rep[1] = MEM_readLE32(dictPtr+4); if (cctx->rep[1] >= dictSize) return ERROR(dictionary_corrupted);
|
|
cctx->rep[2] = MEM_readLE32(dictPtr+8); if (cctx->rep[2] >= dictSize) return ERROR(dictionary_corrupted);
|
|
dictPtr += 12;
|
|
|
|
cctx->flagStaticTables = 1;
|
|
return dictPtr - (const BYTE*)dict;
|
|
}
|
|
|
|
/** ZSTD_compress_insertDictionary() :
|
|
* @return : 0, or an error code */
|
|
static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx* zc, const void* dict, size_t dictSize)
|
|
{
|
|
if ((dict==NULL) || (dictSize<=8)) return 0;
|
|
|
|
/* default : dict is pure content */
|
|
if (MEM_readLE32(dict) != ZSTD_DICT_MAGIC) return ZSTD_loadDictionaryContent(zc, dict, dictSize);
|
|
zc->dictID = zc->params.fParams.noDictIDFlag ? 0 : MEM_readLE32((const char*)dict+4);
|
|
|
|
/* known magic number : dict is parsed for entropy stats and content */
|
|
{ size_t const eSize = ZSTD_loadDictEntropyStats(zc, (const char*)dict+8 /* skip dictHeader */, dictSize-8) + 8;
|
|
if (ZSTD_isError(eSize)) return eSize;
|
|
return ZSTD_loadDictionaryContent(zc, (const char*)dict+eSize, dictSize-eSize);
|
|
}
|
|
}
|
|
|
|
|
|
/*! ZSTD_compressBegin_internal() :
|
|
* @return : 0, or an error code */
|
|
static size_t ZSTD_compressBegin_internal(ZSTD_CCtx* zc,
|
|
const void* dict, size_t dictSize,
|
|
ZSTD_parameters params, U64 pledgedSrcSize)
|
|
{
|
|
size_t const resetError = ZSTD_resetCCtx_advanced(zc, params, pledgedSrcSize, 1);
|
|
if (ZSTD_isError(resetError)) return resetError;
|
|
|
|
return ZSTD_compress_insertDictionary(zc, dict, dictSize);
|
|
}
|
|
|
|
|
|
/*! 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 */
|
|
{ size_t const errorCode = ZSTD_checkCParams_advanced(params.cParams, pledgedSrcSize);
|
|
if (ZSTD_isError(errorCode)) return errorCode; }
|
|
|
|
return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, pledgedSrcSize);
|
|
}
|
|
|
|
|
|
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);
|
|
ZSTD_LOG_BLOCK("%p: ZSTD_compressBegin_usingDict compressionLevel=%d\n", cctx->base, compressionLevel);
|
|
return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0);
|
|
}
|
|
|
|
|
|
size_t ZSTD_compressBegin(ZSTD_CCtx* zc, int compressionLevel)
|
|
{
|
|
ZSTD_LOG_BLOCK("%p: ZSTD_compressBegin compressionLevel=%d\n", zc->base, compressionLevel);
|
|
return ZSTD_compressBegin_usingDict(zc, NULL, 0, compressionLevel);
|
|
}
|
|
|
|
|
|
/*! ZSTD_compressEnd() :
|
|
* Write frame epilogue.
|
|
* @return : nb of bytes written into dst (or an error code) */
|
|
size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity)
|
|
{
|
|
BYTE* op = (BYTE*)dst;
|
|
size_t fhSize = 0;
|
|
|
|
if (cctx->stage==0) return ERROR(stage_wrong); /*< not even init ! */
|
|
|
|
/* special case : empty frame */
|
|
if (cctx->stage==1) {
|
|
fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, 0, 0);
|
|
if (ZSTD_isError(fhSize)) return fhSize;
|
|
dstCapacity -= fhSize;
|
|
op += fhSize;
|
|
cctx->stage = 2;
|
|
}
|
|
|
|
/* frame epilogue */
|
|
if (dstCapacity < ZSTD_blockHeaderSize) return ERROR(dstSize_tooSmall);
|
|
{ U32 const checksum = cctx->params.fParams.checksumFlag ?
|
|
(U32)(XXH64_digest(&cctx->xxhState) >> 11) :
|
|
0;
|
|
MEM_writeLE24(op, (U32)bt_end + (checksum << 2));
|
|
}
|
|
|
|
cctx->stage = 0; /* return to "created but not init" status */
|
|
return ZSTD_blockHeaderSize+fhSize;
|
|
}
|
|
|
|
|
|
/*! ZSTD_compress_usingPreparedCCtx() :
|
|
* Same as ZSTD_compress_usingDict, but using a reference context `preparedCCtx`, where dictionary has been loaded.
|
|
* It avoids reloading the dictionary each time.
|
|
* `preparedCCtx` must have been properly initialized using ZSTD_compressBegin_usingDict() or ZSTD_compressBegin_advanced().
|
|
* Requires 2 contexts : 1 for reference (preparedCCtx) which will not be modified, and 1 to run the compression operation (cctx) */
|
|
static size_t ZSTD_compress_usingPreparedCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
{ size_t const errorCode = ZSTD_copyCCtx(cctx, preparedCCtx);
|
|
if (ZSTD_isError(errorCode)) return errorCode;
|
|
}
|
|
{ size_t const cSize = ZSTD_compressContinue(cctx, dst, dstCapacity, src, srcSize);
|
|
if (ZSTD_isError(cSize)) return cSize;
|
|
|
|
{ size_t const endSize = ZSTD_compressEnd(cctx, (char*)dst+cSize, dstCapacity-cSize);
|
|
if (ZSTD_isError(endSize)) return endSize;
|
|
return cSize + endSize;
|
|
} }
|
|
}
|
|
|
|
|
|
static size_t ZSTD_compress_internal (ZSTD_CCtx* ctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize,
|
|
const void* dict,size_t dictSize,
|
|
ZSTD_parameters params)
|
|
{
|
|
BYTE* const ostart = (BYTE*)dst;
|
|
BYTE* op = ostart;
|
|
|
|
/* Init */
|
|
{ size_t const errorCode = ZSTD_compressBegin_internal(ctx, dict, dictSize, params, srcSize);
|
|
if(ZSTD_isError(errorCode)) return errorCode; }
|
|
|
|
/* body (compression) */
|
|
{ size_t const oSize = ZSTD_compressContinue (ctx, op, dstCapacity, src, srcSize);
|
|
if(ZSTD_isError(oSize)) return oSize;
|
|
op += oSize;
|
|
dstCapacity -= oSize; }
|
|
|
|
/* Close frame */
|
|
{ size_t const oSize = ZSTD_compressEnd(ctx, op, dstCapacity);
|
|
if(ZSTD_isError(oSize)) return oSize;
|
|
op += oSize; }
|
|
|
|
return (op - ostart);
|
|
}
|
|
|
|
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)
|
|
{
|
|
size_t const errorCode = ZSTD_checkCParams_advanced(params.cParams, srcSize);
|
|
if (ZSTD_isError(errorCode)) return errorCode;
|
|
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, dictSize);
|
|
params.fParams.contentSizeFlag = 1;
|
|
ZSTD_LOG_BLOCK("%p: ZSTD_compress_usingDict srcSize=%d dictSize=%d compressionLevel=%d\n", ctx->base, (int)srcSize, (int)dictSize, compressionLevel);
|
|
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)
|
|
{
|
|
ZSTD_LOG_BLOCK("%p: ZSTD_compressCCtx srcSize=%d compressionLevel=%d\n", ctx->base, (int)srcSize, 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));
|
|
memcpy(&ctxBody.customMem, &defaultCustomMem, sizeof(ZSTD_customMem));
|
|
result = ZSTD_compressCCtx(&ctxBody, dst, dstCapacity, src, srcSize, compressionLevel);
|
|
ctxBody.customMem.customFree(ctxBody.customMem.opaque, ctxBody.workSpace); /* can't free ctxBody, since it's on stack; just free heap content */
|
|
return result;
|
|
}
|
|
|
|
|
|
/* ===== Dictionary API ===== */
|
|
|
|
struct ZSTD_CDict_s {
|
|
void* dictContent;
|
|
size_t dictContentSize;
|
|
ZSTD_CCtx* refContext;
|
|
}; /* typedef'd tp ZSTD_CDict within zstd.h */
|
|
|
|
ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize, ZSTD_parameters params, ZSTD_customMem customMem)
|
|
{
|
|
if (!customMem.customAlloc && !customMem.customFree)
|
|
customMem = defaultCustomMem;
|
|
|
|
if (!customMem.customAlloc || !customMem.customFree) /* can't have 1/2 custom alloc/free as NULL */
|
|
return NULL;
|
|
|
|
{ ZSTD_CDict* const cdict = (ZSTD_CDict*) customMem.customAlloc(customMem.opaque, sizeof(*cdict));
|
|
void* const dictContent = customMem.customAlloc(customMem.opaque, dictSize);
|
|
ZSTD_CCtx* const cctx = ZSTD_createCCtx_advanced(customMem);
|
|
|
|
if (!dictContent || !cdict || !cctx) {
|
|
customMem.customFree(customMem.opaque, dictContent);
|
|
customMem.customFree(customMem.opaque, cdict);
|
|
customMem.customFree(customMem.opaque, cctx);
|
|
return NULL;
|
|
}
|
|
|
|
memcpy(dictContent, dict, dictSize);
|
|
{ size_t const errorCode = ZSTD_compressBegin_advanced(cctx, dictContent, dictSize, params, 0);
|
|
if (ZSTD_isError(errorCode)) {
|
|
customMem.customFree(customMem.opaque, dictContent);
|
|
customMem.customFree(customMem.opaque, cdict);
|
|
customMem.customFree(customMem.opaque, cctx);
|
|
return NULL;
|
|
} }
|
|
|
|
cdict->dictContent = dictContent;
|
|
cdict->dictContentSize = dictSize;
|
|
cdict->refContext = cctx;
|
|
return cdict;
|
|
}
|
|
}
|
|
|
|
ZSTD_CDict* ZSTD_createCDict(const void* dict, size_t dictSize, int compressionLevel)
|
|
{
|
|
ZSTD_customMem const allocator = { NULL, NULL, NULL };
|
|
ZSTD_parameters params;
|
|
memset(¶ms, 0, sizeof(params));
|
|
params.cParams = ZSTD_getCParams(compressionLevel, 0, dictSize);
|
|
params.fParams.contentSizeFlag = 1;
|
|
return ZSTD_createCDict_advanced(dict, dictSize, params, allocator);
|
|
}
|
|
|
|
size_t ZSTD_freeCDict(ZSTD_CDict* cdict)
|
|
{
|
|
ZSTD_freeFunction const cFree = cdict->refContext->customMem.customFree;
|
|
void* const opaque = cdict->refContext->customMem.opaque;
|
|
ZSTD_freeCCtx(cdict->refContext);
|
|
cFree(opaque, cdict->dictContent);
|
|
cFree(opaque, cdict);
|
|
return 0;
|
|
}
|
|
|
|
ZSTDLIB_API size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize,
|
|
const ZSTD_CDict* cdict)
|
|
{
|
|
return ZSTD_compress_usingPreparedCCtx(cctx, cdict->refContext,
|
|
dst, dstCapacity,
|
|
src, srcSize);
|
|
}
|
|
|
|
|
|
|
|
/*-===== Pre-defined compression levels =====-*/
|
|
|
|
#define ZSTD_DEFAULT_CLEVEL 1
|
|
#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" */
|
|
/* W, C, H, S, L, TL, strat */
|
|
{ 18, 12, 12, 1, 7, 16, ZSTD_fast }, /* level 0 - not used */
|
|
{ 19, 13, 14, 1, 7, 16, ZSTD_fast }, /* level 1 */
|
|
{ 19, 15, 16, 1, 6, 16, ZSTD_fast }, /* level 2 */
|
|
{ 20, 16, 18, 1, 5, 16, ZSTD_dfast }, /* level 3 */
|
|
{ 20, 13, 17, 2, 5, 16, ZSTD_greedy }, /* level 4.*/
|
|
{ 20, 15, 18, 3, 5, 16, ZSTD_greedy }, /* level 5 */
|
|
{ 21, 16, 19, 2, 5, 16, ZSTD_lazy }, /* level 6 */
|
|
{ 21, 17, 20, 3, 5, 16, ZSTD_lazy }, /* level 7 */
|
|
{ 21, 18, 20, 3, 5, 16, ZSTD_lazy2 }, /* level 8.*/
|
|
{ 21, 20, 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, 21, 5, 5, 16, ZSTD_btlazy2 }, /* level 15 */
|
|
{ 23, 22, 22, 5, 5, 16, ZSTD_btlazy2 }, /* level 16 */
|
|
{ 23, 23, 22, 5, 5, 16, ZSTD_btlazy2 }, /* level 17.*/
|
|
{ 23, 23, 22, 6, 5, 24, ZSTD_btopt }, /* level 18.*/
|
|
{ 23, 23, 22, 6, 3, 48, ZSTD_btopt }, /* level 19.*/
|
|
{ 25, 26, 23, 7, 3, 64, ZSTD_btopt }, /* level 20.*/
|
|
{ 26, 26, 23, 7, 3,256, ZSTD_btopt }, /* level 21.*/
|
|
{ 27, 27, 25, 9, 3,512, ZSTD_btopt }, /* level 22.*/
|
|
},
|
|
{ /* for srcSize <= 256 KB */
|
|
/* W, C, H, S, L, T, strat */
|
|
{ 18, 12, 12, 1, 7, 4, ZSTD_fast }, /* level 0 - not used */
|
|
{ 18, 13, 14, 1, 6, 4, ZSTD_fast }, /* level 1 */
|
|
{ 18, 15, 17, 1, 5, 4, ZSTD_fast }, /* level 2 */
|
|
{ 18, 13, 15, 1, 5, 4, ZSTD_greedy }, /* level 3.*/
|
|
{ 18, 15, 17, 1, 5, 4, ZSTD_greedy }, /* level 4.*/
|
|
{ 18, 16, 17, 4, 5, 4, ZSTD_greedy }, /* level 5 */
|
|
{ 18, 17, 17, 5, 5, 4, ZSTD_greedy }, /* level 6 */
|
|
{ 18, 17, 17, 4, 4, 4, ZSTD_lazy }, /* level 7 */
|
|
{ 18, 17, 17, 4, 4, 4, ZSTD_lazy2 }, /* level 8 */
|
|
{ 18, 17, 17, 5, 4, 4, ZSTD_lazy2 }, /* level 9 */
|
|
{ 18, 17, 17, 6, 4, 4, ZSTD_lazy2 }, /* level 10 */
|
|
{ 18, 18, 17, 6, 4, 4, ZSTD_lazy2 }, /* level 11.*/
|
|
{ 18, 18, 17, 7, 4, 4, ZSTD_lazy2 }, /* level 12.*/
|
|
{ 18, 19, 17, 7, 4, 4, ZSTD_btlazy2 }, /* level 13 */
|
|
{ 18, 18, 18, 4, 4, 16, ZSTD_btopt }, /* level 14.*/
|
|
{ 18, 18, 18, 8, 4, 24, ZSTD_btopt }, /* level 15.*/
|
|
{ 18, 19, 18, 8, 3, 48, ZSTD_btopt }, /* level 16.*/
|
|
{ 18, 19, 18, 8, 3, 96, 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_btopt }, /* level 20.*/
|
|
{ 18, 19, 18, 12, 3,512, ZSTD_btopt }, /* level 21.*/
|
|
{ 18, 19, 18, 13, 3,512, ZSTD_btopt }, /* 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_btopt }, /* level 20.*/
|
|
{ 17, 18, 17, 10, 3,256, ZSTD_btopt }, /* level 21.*/
|
|
{ 17, 18, 17, 11, 3,512, ZSTD_btopt }, /* 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_btopt }, /* level 20.*/
|
|
{ 14, 15, 15, 9, 3,256, ZSTD_btopt }, /* level 21.*/
|
|
{ 14, 15, 15, 10, 3,256, ZSTD_btopt }, /* level 22.*/
|
|
},
|
|
};
|
|
|
|
/*! 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 srcSize, size_t dictSize)
|
|
{
|
|
ZSTD_compressionParameters cp;
|
|
size_t const addedSize = srcSize ? 0 : 500;
|
|
U64 const rSize = srcSize+dictSize ? srcSize+dictSize+addedSize : (U64)-1;
|
|
U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB); /* intentional underflow for srcSizeHint == 0 */
|
|
if (compressionLevel <= 0) compressionLevel = ZSTD_DEFAULT_CLEVEL; /* 0 == default; no negative compressionLevel yet */
|
|
if (compressionLevel > ZSTD_MAX_CLEVEL) compressionLevel = ZSTD_MAX_CLEVEL;
|
|
cp = ZSTD_defaultCParameters[tableID][compressionLevel];
|
|
if (MEM_32bits()) { /* auto-correction, for 32-bits mode */
|
|
if (cp.windowLog > ZSTD_WINDOWLOG_MAX) cp.windowLog = ZSTD_WINDOWLOG_MAX;
|
|
if (cp.chainLog > ZSTD_CHAINLOG_MAX) cp.chainLog = ZSTD_CHAINLOG_MAX;
|
|
if (cp.hashLog > ZSTD_HASHLOG_MAX) cp.hashLog = ZSTD_HASHLOG_MAX;
|
|
}
|
|
cp = ZSTD_adjustCParams(cp, srcSize, dictSize);
|
|
return cp;
|
|
}
|
|
|
|
/*! 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 srcSize, size_t dictSize) {
|
|
ZSTD_parameters params;
|
|
ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSize, dictSize);
|
|
memset(¶ms, 0, sizeof(params));
|
|
params.cParams = cParams;
|
|
return params;
|
|
}
|