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Diffstat (limited to 'lib/zstd/compress.c')
| -rw-r--r-- | lib/zstd/compress.c | 3484 |
1 files changed, 3484 insertions, 0 deletions
diff --git a/lib/zstd/compress.c b/lib/zstd/compress.c new file mode 100644 index 000000000000..f9166cf4f7a9 --- /dev/null +++ b/lib/zstd/compress.c @@ -0,0 +1,3484 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/*-************************************* +* Dependencies +***************************************/ +#include "fse.h" +#include "huf.h" +#include "mem.h" +#include "zstd_internal.h" /* includes zstd.h */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/string.h> /* memset */ + +/*-************************************* +* Constants +***************************************/ +static const U32 g_searchStrength = 8; /* control skip over incompressible data */ +#define HASH_READ_SIZE 8 +typedef enum { ZSTDcs_created = 0, ZSTDcs_init, ZSTDcs_ongoing, ZSTDcs_ending } ZSTD_compressionStage_e; + +/*-************************************* +* Helper functions +***************************************/ +size_t ZSTD_compressBound(size_t srcSize) { return FSE_compressBound(srcSize) + 12; } + +/*-************************************* +* Sequence storage +***************************************/ +static void ZSTD_resetSeqStore(seqStore_t *ssPtr) +{ + ssPtr->lit = ssPtr->litStart; + ssPtr->sequences = ssPtr->sequencesStart; + ssPtr->longLengthID = 0; +} + +/*-************************************* +* Context memory management +***************************************/ +struct ZSTD_CCtx_s { + const BYTE *nextSrc; /* next block here to continue on curr prefix */ + const BYTE *base; /* All regular indexes relative to this position */ + const BYTE *dictBase; /* extDict indexes relative to this position */ + U32 dictLimit; /* below that point, need extDict */ + U32 lowLimit; /* below that point, no more data */ + U32 nextToUpdate; /* index from which to continue dictionary update */ + U32 nextToUpdate3; /* index from which to continue dictionary update */ + U32 hashLog3; /* dispatch table : larger == faster, more memory */ + U32 loadedDictEnd; /* index of end of dictionary */ + U32 forceWindow; /* force back-references to respect limit of 1<<wLog, even for dictionary */ + U32 forceRawDict; /* Force loading dictionary in "content-only" mode (no header analysis) */ + ZSTD_compressionStage_e stage; + U32 rep[ZSTD_REP_NUM]; + U32 repToConfirm[ZSTD_REP_NUM]; + U32 dictID; + ZSTD_parameters params; + void *workSpace; + size_t workSpaceSize; + size_t blockSize; + U64 frameContentSize; + struct xxh64_state xxhState; + ZSTD_customMem customMem; + + seqStore_t seqStore; /* sequences storage ptrs */ + U32 *hashTable; + U32 *hashTable3; + U32 *chainTable; + HUF_CElt *hufTable; + U32 flagStaticTables; + HUF_repeat flagStaticHufTable; + FSE_CTable offcodeCTable[FSE_CTABLE_SIZE_U32(OffFSELog, MaxOff)]; + FSE_CTable matchlengthCTable[FSE_CTABLE_SIZE_U32(MLFSELog, MaxML)]; + FSE_CTable litlengthCTable[FSE_CTABLE_SIZE_U32(LLFSELog, MaxLL)]; + unsigned tmpCounters[HUF_COMPRESS_WORKSPACE_SIZE_U32]; +}; + +size_t ZSTD_CCtxWorkspaceBound(ZSTD_compressionParameters cParams) +{ + size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << cParams.windowLog); + U32 const divider = (cParams.searchLength == 3) ? 3 : 4; + size_t const maxNbSeq = blockSize / divider; + size_t const tokenSpace = blockSize + 11 * maxNbSeq; + size_t const chainSize = (cParams.strategy == ZSTD_fast) ? 0 : (1 << cParams.chainLog); + size_t const hSize = ((size_t)1) << cParams.hashLog; + U32 const hashLog3 = (cParams.searchLength > 3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, cParams.windowLog); + size_t const h3Size = ((size_t)1) << hashLog3; + size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32); + size_t const optSpace = + ((MaxML + 1) + (MaxLL + 1) + (MaxOff + 1) + (1 << Litbits)) * sizeof(U32) + (ZSTD_OPT_NUM + 1) * (sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t)); + size_t const workspaceSize = tableSpace + (256 * sizeof(U32)) /* huffTable */ + tokenSpace + + (((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btopt2)) ? optSpace : 0); + + return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_CCtx)) + ZSTD_ALIGN(workspaceSize); +} + +static ZSTD_CCtx *ZSTD_createCCtx_advanced(ZSTD_customMem customMem) +{ + ZSTD_CCtx *cctx; + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + cctx = (ZSTD_CCtx *)ZSTD_malloc(sizeof(ZSTD_CCtx), customMem); + if (!cctx) + return NULL; + memset(cctx, 0, sizeof(ZSTD_CCtx)); + cctx->customMem = customMem; + return cctx; +} + +ZSTD_CCtx *ZSTD_initCCtx(void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + ZSTD_CCtx *cctx = ZSTD_createCCtx_advanced(stackMem); + if (cctx) { + cctx->workSpace = ZSTD_stackAllocAll(cctx->customMem.opaque, &cctx->workSpaceSize); + } + return cctx; +} + +size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx) +{ + if (cctx == NULL) + return 0; /* support free on NULL */ + ZSTD_free(cctx->workSpace, cctx->customMem); + ZSTD_free(cctx, cctx->customMem); + return 0; /* reserved as a potential error code in the future */ +} + +const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx) /* hidden interface */ { return &(ctx->seqStore); } + +static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx *cctx) { return cctx->params; } + +/** ZSTD_checkParams() : + ensure param values remain within authorized range. + @return : 0, or an error code if one value is beyond authorized range */ +size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams) +{ +#define CLAMPCHECK(val, min, max) \ + { \ + if ((val < min) | (val > max)) \ + return ERROR(compressionParameter_unsupported); \ + } + CLAMPCHECK(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX); + CLAMPCHECK(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX); + CLAMPCHECK(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX); + CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX); + CLAMPCHECK(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX); + CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX); + if ((U32)(cParams.strategy) > (U32)ZSTD_btopt2) + return ERROR(compressionParameter_unsupported); + return 0; +} + +/** ZSTD_cycleLog() : + * condition for correct operation : hashLog > 1 */ +static U32 ZSTD_cycleLog(U32 hashLog, ZSTD_strategy strat) +{ + U32 const btScale = ((U32)strat >= (U32)ZSTD_btlazy2); + return hashLog - btScale; +} + +/** ZSTD_adjustCParams() : + optimize `cPar` for a given input (`srcSize` and `dictSize`). + mostly downsizing to reduce memory consumption and initialization. + Both `srcSize` and `dictSize` are optional (use 0 if unknown), + but if both are 0, no optimization can be done. + Note : cPar is considered validated at this stage. Use ZSTD_checkParams() to ensure that. */ +ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize) +{ + if (srcSize + dictSize == 0) + return cPar; /* no size information available : no adjustment */ + + /* resize params, to use less memory when necessary */ + { + U32 const minSrcSize = (srcSize == 0) ? 500 : 0; + U64 const rSize = srcSize + dictSize + minSrcSize; + if (rSize < ((U64)1 << ZSTD_WINDOWLOG_MAX)) { + U32 const srcLog = MAX(ZSTD_HASHLOG_MIN, ZSTD_highbit32((U32)(rSize)-1) + 1); + if (cPar.windowLog > srcLog) + cPar.windowLog = srcLog; + } + } + if (cPar.hashLog > cPar.windowLog) + cPar.hashLog = cPar.windowLog; + { + U32 const cycleLog = ZSTD_cycleLog(cPar.chainLog, cPar.strategy); + if (cycleLog > cPar.windowLog) + cPar.chainLog -= (cycleLog - cPar.windowLog); + } + + if (cPar.windowLog < ZSTD_WINDOWLOG_ABSOLUTEMIN) + cPar.windowLog = ZSTD_WINDOWLOG_ABSOLUTEMIN; /* required for frame header */ + + return cPar; +} + +static U32 ZSTD_equivalentParams(ZSTD_parameters param1, ZSTD_parameters param2) +{ + return (param1.cParams.hashLog == param2.cParams.hashLog) & (param1.cParams.chainLog == param2.cParams.chainLog) & + (param1.cParams.strategy == param2.cParams.strategy) & ((param1.cParams.searchLength == 3) == (param2.cParams.searchLength == 3)); +} + +/*! ZSTD_continueCCtx() : + reuse CCtx without reset (note : requires no dictionary) */ +static size_t ZSTD_continueCCtx(ZSTD_CCtx *cctx, ZSTD_parameters params, U64 frameContentSize) +{ + U32 const end = (U32)(cctx->nextSrc - cctx->base); + cctx->params = params; + cctx->frameContentSize = frameContentSize; + cctx->lowLimit = end; + cctx->dictLimit = end; + cctx->nextToUpdate = end + 1; + cctx->stage = ZSTDcs_init; + cctx->dictID = 0; + cctx->loadedDictEnd = 0; + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + cctx->rep[i] = repStartValue[i]; + } + cctx->seqStore.litLengthSum = 0; /* force reset of btopt stats */ + xxh64_reset(&cctx->xxhState, 0); + return 0; +} + +typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset, ZSTDcrp_fullReset } ZSTD_compResetPolicy_e; + +/*! ZSTD_resetCCtx_advanced() : + note : `params` must be validated */ +static size_t ZSTD_resetCCtx_advanced(ZSTD_CCtx *zc, ZSTD_parameters params, U64 frameContentSize, ZSTD_compResetPolicy_e const crp) +{ + if (crp == ZSTDcrp_continue) + if (ZSTD_equivalentParams(params, zc->params)) { + zc->flagStaticTables = 0; + zc->flagStaticHufTable = HUF_repeat_none; + return ZSTD_continueCCtx(zc, params, frameContentSize); + } + + { + size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << params.cParams.windowLog); + U32 const divider = (params.cParams.searchLength == 3) ? 3 : 4; + size_t const maxNbSeq = blockSize / divider; + size_t const tokenSpace = blockSize + 11 * maxNbSeq; + size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ? 0 : (1 << params.cParams.chainLog); + size_t const hSize = ((size_t)1) << params.cParams.hashLog; + U32 const hashLog3 = (params.cParams.searchLength > 3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog); + size_t const h3Size = ((size_t)1) << hashLog3; + size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32); + void *ptr; + + /* Check if workSpace is large enough, alloc a new one if needed */ + { + size_t const optSpace = ((MaxML + 1) + (MaxLL + 1) + (MaxOff + 1) + (1 << Litbits)) * sizeof(U32) + + (ZSTD_OPT_NUM + 1) * (sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t)); + size_t const neededSpace = tableSpace + (256 * sizeof(U32)) /* huffTable */ + tokenSpace + + (((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) ? optSpace : 0); + if (zc->workSpaceSize < neededSpace) { + ZSTD_free(zc->workSpace, zc->customMem); + zc->workSpace = ZSTD_malloc(neededSpace, zc->customMem); + if (zc->workSpace == NULL) + return ERROR(memory_allocation); + zc->workSpaceSize = neededSpace; + } + } + + if (crp != ZSTDcrp_noMemset) + memset(zc->workSpace, 0, tableSpace); /* reset tables only */ + xxh64_reset(&zc->xxhState, 0); + zc->hashLog3 = hashLog3; + zc->hashTable = (U32 *)(zc->workSpace); + zc->chainTable = zc->hashTable + hSize; + zc->hashTable3 = zc->chainTable + chainSize; + ptr = zc->hashTable3 + h3Size; + zc->hufTable = (HUF_CElt *)ptr; + zc->flagStaticTables = 0; + zc->flagStaticHufTable = HUF_repeat_none; + ptr = ((U32 *)ptr) + 256; /* note : HUF_CElt* is incomplete type, size is simulated using U32 */ + + zc->nextToUpdate = 1; + zc->nextSrc = NULL; + zc->base = NULL; + zc->dictBase = NULL; + zc->dictLimit = 0; + zc->lowLimit = 0; + zc->params = params; + zc->blockSize = blockSize; + zc->frameContentSize = frameContentSize; + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + zc->rep[i] = repStartValue[i]; + } + + if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) { + zc->seqStore.litFreq = (U32 *)ptr; + zc->seqStore.litLengthFreq = zc->seqStore.litFreq + (1 << Litbits); + zc->seqStore.matchLengthFreq = zc->seqStore.litLengthFreq + (MaxLL + 1); + zc->seqStore.offCodeFreq = zc->seqStore.matchLengthFreq + (MaxML + 1); + ptr = zc->seqStore.offCodeFreq + (MaxOff + 1); + zc->seqStore.matchTable = (ZSTD_match_t *)ptr; + ptr = zc->seqStore.matchTable + ZSTD_OPT_NUM + 1; + zc->seqStore.priceTable = (ZSTD_optimal_t *)ptr; + ptr = zc->seqStore.priceTable + ZSTD_OPT_NUM + 1; + zc->seqStore.litLengthSum = 0; + } + zc->seqStore.sequencesStart = (seqDef *)ptr; + ptr = zc->seqStore.sequencesStart + maxNbSeq; + zc->seqStore.llCode = (BYTE *)ptr; + zc->seqStore.mlCode = zc->seqStore.llCode + maxNbSeq; + zc->seqStore.ofCode = zc->seqStore.mlCode + maxNbSeq; + zc->seqStore.litStart = zc->seqStore.ofCode + maxNbSeq; + + zc->stage = ZSTDcs_init; + zc->dictID = 0; + zc->loadedDictEnd = 0; + + return 0; + } +} + +/* ZSTD_invalidateRepCodes() : + * ensures next compression will not use repcodes from previous block. + * Note : only works with regular variant; + * do not use with extDict variant ! */ +void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx) +{ + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + cctx->rep[i] = 0; +} + +/*! ZSTD_copyCCtx() : +* Duplicate an existing context `srcCCtx` into another one `dstCCtx`. +* Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()). +* @return : 0, or an error code */ +size_t ZSTD_copyCCtx(ZSTD_CCtx *dstCCtx, const ZSTD_CCtx *srcCCtx, unsigned long long pledgedSrcSize) +{ + if (srcCCtx->stage != ZSTDcs_init) + return ERROR(stage_wrong); + + memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem)); + { + ZSTD_parameters params = srcCCtx->params; + params.fParams.contentSizeFlag = (pledgedSrcSize > 0); + ZSTD_resetCCtx_advanced(dstCCtx, params, pledgedSrcSize, ZSTDcrp_noMemset); + } + + /* copy tables */ + { + size_t const chainSize = (srcCCtx->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->params.cParams.chainLog); + size_t const hSize = ((size_t)1) << srcCCtx->params.cParams.hashLog; + size_t const h3Size = (size_t)1 << srcCCtx->hashLog3; + size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32); + memcpy(dstCCtx->workSpace, srcCCtx->workSpace, tableSpace); + } + + /* copy dictionary offsets */ + dstCCtx->nextToUpdate = srcCCtx->nextToUpdate; + dstCCtx->nextToUpdate3 = srcCCtx->nextToUpdate3; + dstCCtx->nextSrc = srcCCtx->nextSrc; + dstCCtx->base = srcCCtx->base; + dstCCtx->dictBase = srcCCtx->dictBase; + dstCCtx->dictLimit = srcCCtx->dictLimit; + dstCCtx->lowLimit = srcCCtx->lowLimit; + dstCCtx->loadedDictEnd = srcCCtx->loadedDictEnd; + dstCCtx->dictID = srcCCtx->dictID; + + /* copy entropy tables */ + dstCCtx->flagStaticTables = srcCCtx->flagStaticTables; + dstCCtx->flagStaticHufTable = srcCCtx->flagStaticHufTable; + if (srcCCtx->flagStaticTables) { + memcpy(dstCCtx->litlengthCTable, srcCCtx->litlengthCTable, sizeof(dstCCtx->litlengthCTable)); + memcpy(dstCCtx->matchlengthCTable, srcCCtx->matchlengthCTable, sizeof(dstCCtx->matchlengthCTable)); + memcpy(dstCCtx->offcodeCTable, srcCCtx->offcodeCTable, sizeof(dstCCtx->offcodeCTable)); + } + if (srcCCtx->flagStaticHufTable) { + memcpy(dstCCtx->hufTable, srcCCtx->hufTable, 256 * 4); + } + + return 0; +} + +/*! ZSTD_reduceTable() : +* reduce table indexes by `reducerValue` */ +static void ZSTD_reduceTable(U32 *const table, U32 const size, U32 const reducerValue) +{ + U32 u; + for (u = 0; u < size; u++) { + if (table[u] < reducerValue) + table[u] = 0; + else + table[u] -= reducerValue; + } +} + +/*! ZSTD_reduceIndex() : +* rescale all indexes to avoid future overflow (indexes are U32) */ +static void ZSTD_reduceIndex(ZSTD_CCtx *zc, const U32 reducerValue) +{ + { + U32 const hSize = 1 << zc->params.cParams.hashLog; + ZSTD_reduceTable(zc->hashTable, hSize, reducerValue); + } + + { + U32 const chainSize = (zc->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->params.cParams.chainLog); + ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue); + } + + { + U32 const h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0; + ZSTD_reduceTable(zc->hashTable3, h3Size, reducerValue); + } +} + +/*-******************************************************* +* Block entropic compression +*********************************************************/ + +/* See doc/zstd_compression_format.md for detailed format description */ + +size_t ZSTD_noCompressBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + if (srcSize + ZSTD_blockHeaderSize > dstCapacity) + return ERROR(dstSize_tooSmall); + memcpy((BYTE *)dst + ZSTD_blockHeaderSize, src, srcSize); + ZSTD_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 */ ZSTD_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 */ ZSTD_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 */ ZSTD_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 */ ZSTD_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->flagStaticHufTable == HUF_repeat_valid ? 6 : LITERAL_NOENTROPY; + if (srcSize <= minLitSize) + return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize); + } + + if (dstCapacity < lhSize + 1) + return ERROR(dstSize_tooSmall); /* not enough space for compression */ + { + HUF_repeat repeat = zc->flagStaticHufTable; + int const preferRepeat = zc->params.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0; + if (repeat == HUF_repeat_valid && lhSize == 3) + singleStream = 1; + cLitSize = singleStream ? HUF_compress1X_repeat(ostart + lhSize, dstCapacity - lhSize, src, srcSize, 255, 11, zc->tmpCounters, + sizeof(zc->tmpCounters), zc->hufTable, &repeat, preferRepeat) + : HUF_compress4X_repeat(ostart + lhSize, dstCapacity - lhSize, src, srcSize, 255, 11, zc->tmpCounters, + sizeof(zc->tmpCounters), zc->hufTable, &repeat, preferRepeat); + if (repeat != HUF_repeat_none) { + hType = set_repeat; + } /* reused the existing table */ + else { + zc->flagStaticHufTable = HUF_repeat_check; + } /* now have a table to reuse */ + } + + if ((cLitSize == 0) | (cLitSize >= srcSize - minGain)) { + zc->flagStaticHufTable = HUF_repeat_none; + return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize); + } + if (cLitSize == 1) { + zc->flagStaticHufTable = HUF_repeat_none; + return ZSTD_compressRleLiteralsBlock(dst, dstCapacity, src, srcSize); + } + + /* Build header */ + switch (lhSize) { + case 3: /* 2 - 2 - 10 - 10 */ + { + U32 const lhc = hType + ((!singleStream) << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 14); + ZSTD_writeLE24(ostart, lhc); + break; + } + case 4: /* 2 - 2 - 14 - 14 */ + { + U32 const lhc = hType + (2 << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 18); + ZSTD_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); + ZSTD_writeLE32(ostart, lhc); + ostart[4] = (BYTE)(cLitSize >> 10); + break; + } + } + return lhSize + cLitSize; +} + +static const BYTE LL_Code[64] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 16, 17, 17, 18, 18, + 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, + 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24}; + +static const BYTE ML_Code[128] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, + 26, 27, 28, 29, 30, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 36, 36, 36, 37, 37, 37, 37, 38, 38, 38, 38, + 38, 38, 38, 38, 39, 39, 39, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, + 40, 40, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 42, 42, 42, 42, 42, 42, 42, 42, + 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42}; + +void ZSTD_seqToCodes(const seqStore_t *seqStorePtr) +{ + BYTE const LL_deltaCode = 19; + BYTE const ML_deltaCode = 36; + const seqDef *const sequences = seqStorePtr->sequencesStart; + BYTE *const llCodeTable = seqStorePtr->llCode; + BYTE *const ofCodeTable = seqStorePtr->ofCode; + BYTE *const mlCodeTable = seqStorePtr->mlCode; + U32 const nbSeq = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart); + U32 u; + for (u = 0; u < nbSeq; u++) { + U32 const llv = sequences[u].litLength; + U32 const mlv = sequences[u].matchLength; + llCodeTable[u] = (llv > 63) ? (BYTE)ZSTD_highbit32(llv) + LL_deltaCode : LL_Code[llv]; + ofCodeTable[u] = (BYTE)ZSTD_highbit32(sequences[u].offset); + mlCodeTable[u] = (mlv > 127) ? (BYTE)ZSTD_highbit32(mlv) + ML_deltaCode : ML_Code[mlv]; + } + if (seqStorePtr->longLengthID == 1) + llCodeTable[seqStorePtr->longLengthPos] = MaxLL; + if (seqStorePtr->longLengthID == 2) + mlCodeTable[seqStorePtr->longLengthPos] = MaxML; +} + +ZSTD_STATIC size_t ZSTD_compressSequences_internal(ZSTD_CCtx *zc, void *dst, size_t dstCapacity) +{ + const int longOffsets = zc->params.cParams.windowLog > STREAM_ACCUMULATOR_MIN; + const seqStore_t *seqStorePtr = &(zc->seqStore); + FSE_CTable *CTable_LitLength = zc->litlengthCTable; + FSE_CTable *CTable_OffsetBits = zc->offcodeCTable; + FSE_CTable *CTable_MatchLength = zc->matchlengthCTable; + U32 LLtype, Offtype, MLtype; /* compressed, raw or rle */ + const seqDef *const sequences = seqStorePtr->sequencesStart; + const BYTE *const ofCodeTable = seqStorePtr->ofCode; + const BYTE *const llCodeTable = seqStorePtr->llCode; + const BYTE *const mlCodeTable = seqStorePtr->mlCode; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstCapacity; + BYTE *op = ostart; + size_t const nbSeq = seqStorePtr->sequences - seqStorePtr->sequencesStart; + BYTE *seqHead; + + U32 *count; + S16 *norm; + U32 *workspace; + size_t workspaceSize = sizeof(zc->tmpCounters); + { + size_t spaceUsed32 = 0; + count = (U32 *)zc->tmpCounters + spaceUsed32; + spaceUsed32 += MaxSeq + 1; + norm = (S16 *)((U32 *)zc->tmpCounters + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(S16) * (MaxSeq + 1), sizeof(U32)) >> 2; + + workspace = (U32 *)zc->tmpCounters + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + } + + /* 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, ZSTD_writeLE16(op + 1, (U16)(nbSeq - LONGNBSEQ)), op += 3; + if (nbSeq == 0) + return op - ostart; + + /* seqHead : flags for FSE encoding type */ + seqHead = op++; + +#define MIN_SEQ_FOR_DYNAMIC_FSE 64 +#define MAX_SEQ_FOR_STATIC_FSE 1000 + + /* convert length/distances into codes */ + ZSTD_seqToCodes(seqStorePtr); + + /* CTable for Literal Lengths */ + { + U32 max = MaxLL; + size_t const mostFrequent = FSE_countFast_wksp(count, &max, llCodeTable, nbSeq, workspace); + 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_wksp(CTable_LitLength, LL_defaultNorm, MaxLL, LL_defaultNormLog, workspace, workspaceSize); + LLtype = set_basic; + } else { + size_t nbSeq_1 = nbSeq; + const U32 tableLog = FSE_optimalTableLog(LLFSELog, nbSeq, max); + if (count[llCodeTable[nbSeq - 1]] > 1) { + count[llCodeTable[nbSeq - 1]]--; + nbSeq_1--; + } + FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max); + { + size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */ + if (FSE_isError(NCountSize)) + return NCountSize; + op += NCountSize; + } + FSE_buildCTable_wksp(CTable_LitLength, norm, max, tableLog, workspace, workspaceSize); + LLtype = set_compressed; + } + } + + /* CTable for Offsets */ + { + U32 max = MaxOff; + size_t const mostFrequent = FSE_countFast_wksp(count, &max, ofCodeTable, nbSeq, workspace); + 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_wksp(CTable_OffsetBits, OF_defaultNorm, MaxOff, OF_defaultNormLog, workspace, workspaceSize); + Offtype = set_basic; + } else { + size_t nbSeq_1 = nbSeq; + const U32 tableLog = FSE_optimalTableLog(OffFSELog, nbSeq, max); + if (count[ofCodeTable[nbSeq - 1]] > 1) { + count[ofCodeTable[nbSeq - 1]]--; + nbSeq_1--; + } + FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max); + { + size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */ + if (FSE_isError(NCountSize)) + return NCountSize; + op += NCountSize; + } + FSE_buildCTable_wksp(CTable_OffsetBits, norm, max, tableLog, workspace, workspaceSize); + Offtype = set_compressed; + } + } + + /* CTable for MatchLengths */ + { + U32 max = MaxML; + size_t const mostFrequent = FSE_countFast_wksp(count, &max, mlCodeTable, nbSeq, workspace); + 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_wksp(CTable_MatchLength, ML_defaultNorm, MaxML, ML_defaultNormLog, workspace, workspaceSize); + MLtype = set_basic; + } else { + size_t nbSeq_1 = nbSeq; + const U32 tableLog = FSE_optimalTableLog(MLFSELog, nbSeq, max); + if (count[mlCodeTable[nbSeq - 1]] > 1) { + count[mlCodeTable[nbSeq - 1]]--; + nbSeq_1--; + } + FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max); + { + size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */ + if (FSE_isError(NCountSize)) + return NCountSize; + op += NCountSize; + } + FSE_buildCTable_wksp(CTable_MatchLength, norm, max, tableLog, workspace, workspaceSize); + 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; + + CHECK_E(BIT_initCStream(&blockStream, op, oend - op), dstSize_tooSmall); /* not enough space remaining */ + + /* first symbols */ + FSE_initCState2(&stateMatchLength, CTable_MatchLength, mlCodeTable[nbSeq - 1]); + FSE_initCState2(&stateOffsetBits, CTable_OffsetBits, ofCodeTable[nbSeq - 1]); + FSE_initCState2(&stateLitLength, CTable_LitLength, llCodeTable[nbSeq - 1]); + BIT_addBits(&blockStream, sequences[nbSeq - 1].litLength, LL_bits[llCodeTable[nbSeq - 1]]); + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); + BIT_addBits(&blockStream, sequences[nbSeq - 1].matchLength, ML_bits[mlCodeTable[nbSeq - 1]]); + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); + if (longOffsets) { + U32 const ofBits = ofCodeTable[nbSeq - 1]; + int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN - 1); + if (extraBits) { + BIT_addBits(&blockStream, sequences[nbSeq - 1].offset, extraBits); + BIT_flushBits(&blockStream); + } + BIT_addBits(&blockStream, sequences[nbSeq - 1].offset >> extraBits, ofBits - extraBits); + } else { + BIT_addBits(&blockStream, sequences[nbSeq - 1].offset, ofCodeTable[nbSeq - 1]); + } + BIT_flushBits(&blockStream); + + { + size_t n; + for (n = nbSeq - 2; n < nbSeq; n--) { /* intentional underflow */ + BYTE const llCode = llCodeTable[n]; + BYTE const ofCode = ofCodeTable[n]; + BYTE const mlCode = mlCodeTable[n]; + U32 const llBits = LL_bits[llCode]; + U32 const ofBits = ofCode; /* 32b*/ /* 64b*/ + U32 const mlBits = ML_bits[mlCode]; + /* (7)*/ /* (7)*/ + FSE_encodeSymbol(&blockStream, &stateOffsetBits, ofCode); /* 15 */ /* 15 */ + FSE_encodeSymbol(&blockStream, &stateMatchLength, mlCode); /* 24 */ /* 24 */ + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); /* (7)*/ + FSE_encodeSymbol(&blockStream, &stateLitLength, llCode); /* 16 */ /* 33 */ + if (ZSTD_32bits() || (ofBits + mlBits + llBits >= 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) + BIT_flushBits(&blockStream); /* (7)*/ + BIT_addBits(&blockStream, sequences[n].litLength, llBits); + if (ZSTD_32bits() && ((llBits + mlBits) > 24)) + BIT_flushBits(&blockStream); + BIT_addBits(&blockStream, sequences[n].matchLength, mlBits); + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); /* (7)*/ + if (longOffsets) { + int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN - 1); + if (extraBits) { + BIT_addBits(&blockStream, sequences[n].offset, extraBits); + BIT_flushBits(&blockStream); /* (7)*/ + } + BIT_addBits(&blockStream, sequences[n].offset >> extraBits, ofBits - extraBits); /* 31 */ + } else { + BIT_addBits(&blockStream, sequences[n].offset, ofBits); /* 31 */ + } + BIT_flushBits(&blockStream); /* (7)*/ + } + } + + FSE_flushCState(&blockStream, &stateMatchLength); + FSE_flushCState(&blockStream, &stateOffsetBits); + FSE_flushCState(&blockStream, &stateLitLength); + + { + size_t const streamSize = BIT_closeCStream(&blockStream); + if (streamSize == 0) + return ERROR(dstSize_tooSmall); /* not enough space */ + op += streamSize; + } + } + return op - ostart; +} + +ZSTD_STATIC size_t ZSTD_compressSequences(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, size_t srcSize) +{ + size_t const cSize = ZSTD_compressSequences_internal(zc, dst, dstCapacity); + size_t const minGain = ZSTD_minGain(srcSize); + size_t const maxCSize = srcSize - minGain; + /* If the srcSize <= dstCapacity, then there is enough space to write a + * raw uncompressed block. Since we ran out of space, the block must not + * be compressible, so fall back to a raw uncompressed block. + */ + int const uncompressibleError = cSize == ERROR(dstSize_tooSmall) && srcSize <= dstCapacity; + int i; + + if (ZSTD_isError(cSize) && !uncompressibleError) + return cSize; + if (cSize >= maxCSize || uncompressibleError) { + zc->flagStaticHufTable = HUF_repeat_none; + return 0; + } + /* confirm repcodes */ + for (i = 0; i < ZSTD_REP_NUM; i++) + zc->rep[i] = zc->repToConfirm[i]; + return cSize; +} + +/*! 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 +*/ +ZSTD_STATIC void ZSTD_storeSeq(seqStore_t *seqStorePtr, size_t litLength, const void *literals, U32 offsetCode, size_t matchCode) +{ + /* copy Literals */ + ZSTD_wildcopy(seqStorePtr->lit, literals, litLength); + seqStorePtr->lit += litLength; + + /* literal Length */ + if (litLength > 0xFFFF) { + seqStorePtr->longLengthID = 1; + seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart); + } + seqStorePtr->sequences[0].litLength = (U16)litLength; + + /* match offset */ + seqStorePtr->sequences[0].offset = offsetCode + 1; + + /* match Length */ + if (matchCode > 0xFFFF) { + seqStorePtr->longLengthID = 2; + seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart); + } + seqStorePtr->sequences[0].matchLength = (U16)matchCode; + + seqStorePtr->sequences++; +} + +/*-************************************* +* Match length counter +***************************************/ +static unsigned ZSTD_NbCommonBytes(register size_t val) +{ + if (ZSTD_isLittleEndian()) { + if (ZSTD_64bits()) { + return (__builtin_ctzll((U64)val) >> 3); + } else { /* 32 bits */ + return (__builtin_ctz((U32)val) >> 3); + } + } else { /* Big Endian CPU */ + if (ZSTD_64bits()) { + return (__builtin_clzll(val) >> 3); + } else { /* 32 bits */ + return (__builtin_clz((U32)val) >> 3); + } + } +} + +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 = ZSTD_readST(pMatch) ^ ZSTD_readST(pIn); + if (!diff) { + pIn += sizeof(size_t); + pMatch += sizeof(size_t); + continue; + } + pIn += ZSTD_NbCommonBytes(diff); + return (size_t)(pIn - pStart); + } + if (ZSTD_64bits()) + if ((pIn < (pInLimit - 3)) && (ZSTD_read32(pMatch) == ZSTD_read32(pIn))) { + pIn += 4; + pMatch += 4; + } + if ((pIn < (pInLimit - 1)) && (ZSTD_read16(pMatch) == ZSTD_read16(pIn))) { + pIn += 2; + pMatch += 2; + } + if ((pIn < pInLimit) && (*pMatch == *pIn)) + pIn++; + return (size_t)(pIn - pStart); +} + +/** ZSTD_count_2segments() : +* can count match length with `ip` & `match` in 2 different segments. +* convention : on reaching mEnd, match count continue starting from iStart +*/ +static size_t ZSTD_count_2segments(const BYTE *ip, const BYTE *match, const BYTE *iEnd, const BYTE *mEnd, const BYTE *iStart) +{ + const BYTE *const vEnd = MIN(ip + (mEnd - match), iEnd); + size_t const matchLength = ZSTD_count(ip, match, vEnd); + if (match + matchLength != mEnd) + return matchLength; + return matchLength + ZSTD_count(ip + matchLength, iStart, iEnd); +} + +/*-************************************* +* Hashes +***************************************/ +static const U32 prime3bytes = 506832829U; +static U32 ZSTD_hash3(U32 u, U32 h) { return ((u << (32 - 24)) * prime3bytes) >> (32 - h); } +ZSTD_STATIC size_t ZSTD_hash3Ptr(const void *ptr, U32 h) { return ZSTD_hash3(ZSTD_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(ZSTD_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(ZSTD_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(ZSTD_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(ZSTD_readLE64(p), h); } + +static const U64 prime8bytes = 0xCF1BBCDCB7A56463ULL; +static size_t ZSTD_hash8(U64 u, U32 h) { return (size_t)(((u)*prime8bytes) >> (64 - h)); } +static size_t ZSTD_hash8Ptr(const void *p, U32 h) { return ZSTD_hash8(ZSTD_readLE64(p), h); } + +static size_t ZSTD_hashPtr(const void *p, U32 hBits, U32 mls) +{ + switch (mls) { + // case 3: return ZSTD_hash3Ptr(p, hBits); + default: + case 4: return ZSTD_hash4Ptr(p, hBits); + case 5: return ZSTD_hash5Ptr(p, hBits); + case 6: return ZSTD_hash6Ptr(p, hBits); + case 7: return ZSTD_hash7Ptr(p, hBits); + case 8: return ZSTD_hash8Ptr(p, hBits); + } +} + +/*-************************************* +* Fast Scan +***************************************/ +static void ZSTD_fillHashTable(ZSTD_CCtx *zc, const void *end, const U32 mls) +{ + U32 *const hashTable = zc->hashTable; + U32 const hBits = zc->params.cParams.hashLog; + const BYTE *const base = zc->base; + const BYTE *ip = base + zc->nextToUpdate; + const BYTE *const iend = ((const BYTE *)end) - HASH_READ_SIZE; + const size_t fastHashFillStep = 3; + + while (ip <= iend) { + hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip - base); + ip += fastHashFillStep; + } +} + +FORCE_INLINE +void ZSTD_compressBlock_fast_generic(ZSTD_CCtx *cctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *const hashTable = cctx->hashTable; + U32 const hBits = cctx->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 - HASH_READ_SIZE; + U32 offset_1 = cctx->rep[0], offset_2 = cctx->rep[1]; + U32 offsetSaved = 0; + + /* init */ + ip += (ip == lowest); + { + U32 const maxRep = (U32)(ip - lowest); + if (offset_2 > maxRep) + offsetSaved = offset_2, offset_2 = 0; + if (offset_1 > maxRep) + offsetSaved = offset_1, offset_1 = 0; + } + + /* Main Search Loop */ + while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */ + size_t mLength; + size_t const h = ZSTD_hashPtr(ip, hBits, mls); + U32 const curr = (U32)(ip - base); + U32 const matchIndex = hashTable[h]; + const BYTE *match = base + matchIndex; + hashTable[h] = curr; /* update hash table */ + + if ((offset_1 > 0) & (ZSTD_read32(ip + 1 - offset_1) == ZSTD_read32(ip + 1))) { + mLength = ZSTD_count(ip + 1 + 4, ip + 1 + 4 - offset_1, iend) + 4; + ip++; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH); + } else { + U32 offset; + if ((matchIndex <= lowestIndex) || (ZSTD_read32(match) != ZSTD_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 + curr + 2, hBits, mls)] = curr + 2; /* here because curr+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) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) { + /* store sequence */ + size_t const rLength = ZSTD_count(ip + 4, ip + 4 - offset_2, iend) + 4; + { + U32 const tmpOff = offset_2; + offset_2 = offset_1; + offset_1 = tmpOff; + } /* swap offset_2 <=> offset_1 */ + hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip - base); + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength - MINMATCH); + ip += rLength; + anchor = ip; + continue; /* faster when present ... (?) */ + } + } + } + + /* save reps for next block */ + cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved; + cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_fast(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + const U32 mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 7); return; + } +} + +static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *hashTable = ctx->hashTable; + const U32 hBits = ctx->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 curr = (U32)(ip - base); + const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */ + const BYTE *repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *repMatch = repBase + repIndex; + size_t mLength; + hashTable[h] = curr; /* update hash table */ + + if ((((U32)((dictLimit - 1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex)) && + (ZSTD_read32(repMatch) == ZSTD_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) || (ZSTD_read32(match) != ZSTD_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 = curr - 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 + curr + 2, hBits, mls)] = curr + 2; + hashTable[ZSTD_hashPtr(ip - 2, hBits, mls)] = (U32)(ip - 2 - base); + /* check immediate repcode */ + while (ip <= ilimit) { + U32 const curr2 = (U32)(ip - base); + U32 const repIndex2 = curr2 - offset_2; + const BYTE *repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2; + if ((((U32)((dictLimit - 1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */ + && (ZSTD_read32(repMatch2) == ZSTD_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)] = curr2; + ip += repLength2; + anchor = ip; + continue; + } + break; + } + } + } + + /* save reps for next block */ + ctx->repToConfirm[0] = offset_1; + ctx->repToConfirm[1] = offset_2; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + U32 const mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 7); return; + } +} + +/*-************************************* +* Double Fast +***************************************/ +static void ZSTD_fillDoubleHashTable(ZSTD_CCtx *cctx, const void *end, const U32 mls) +{ + U32 *const hashLarge = cctx->hashTable; + U32 const hBitsL = cctx->params.cParams.hashLog; + U32 *const hashSmall = cctx->chainTable; + U32 const hBitsS = cctx->params.cParams.chainLog; + const BYTE *const base = cctx->base; + const BYTE *ip = base + cctx->nextToUpdate; + const BYTE *const iend = ((const BYTE *)end) - HASH_READ_SIZE; + const size_t fastHashFillStep = 3; + + while (ip <= iend) { + hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip - base); + hashLarge[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip - base); + ip += fastHashFillStep; + } +} + +FORCE_INLINE +void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx *cctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *const hashLong = cctx->hashTable; + const U32 hBitsL = cctx->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 - HASH_READ_SIZE; + U32 offset_1 = cctx->rep[0], offset_2 = cctx->rep[1]; + U32 offsetSaved = 0; + + /* init */ + ip += (ip == lowest); + { + U32 const maxRep = (U32)(ip - lowest); + if (offset_2 > maxRep) + offsetSaved = offset_2, offset_2 = 0; + if (offset_1 > maxRep) + offsetSaved = offset_1, offset_1 = 0; + } + + /* Main Search Loop */ + while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */ + size_t mLength; + size_t const h2 = ZSTD_hashPtr(ip, hBitsL, 8); + size_t const h = ZSTD_hashPtr(ip, hBitsS, mls); + U32 const curr = (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] = curr; /* update hash tables */ + + if ((offset_1 > 0) & (ZSTD_read32(ip + 1 - offset_1) == ZSTD_read32(ip + 1))) { /* note : by construction, offset_1 <= curr */ + 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) && (ZSTD_read64(matchLong) == ZSTD_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) && (ZSTD_read32(match) == ZSTD_read32(ip))) { + size_t const h3 = ZSTD_hashPtr(ip + 1, hBitsL, 8); + U32 const matchIndex3 = hashLong[h3]; + const BYTE *match3 = base + matchIndex3; + hashLong[h3] = curr + 1; + if ((matchIndex3 > lowestIndex) && (ZSTD_read64(match3) == ZSTD_read64(ip + 1))) { + mLength = ZSTD_count(ip + 9, match3 + 8, iend) + 8; + ip++; + offset = (U32)(ip - match3); + while (((ip > anchor) & (match3 > lowest)) && (ip[-1] == match3[-1])) { + ip--; + match3--; + mLength++; + } /* catch up */ + } else { + mLength = ZSTD_count(ip + 4, match + 4, iend) + 4; + offset = (U32)(ip - match); + while (((ip > anchor) & (match > lowest)) && (ip[-1] == match[-1])) { + ip--; + match--; + mLength++; + } /* catch up */ + } + } else { + ip += ((ip - anchor) >> g_searchStrength) + 1; + continue; + } + + offset_2 = offset_1; + offset_1 = offset; + + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH); + } + + /* match found */ + ip += mLength; + anchor = ip; + + if (ip <= ilimit) { + /* Fill Table */ + hashLong[ZSTD_hashPtr(base + curr + 2, hBitsL, 8)] = hashSmall[ZSTD_hashPtr(base + curr + 2, hBitsS, mls)] = + curr + 2; /* here because curr+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) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) { + /* store sequence */ + size_t const rLength = ZSTD_count(ip + 4, ip + 4 - offset_2, iend) + 4; + { + U32 const tmpOff = offset_2; + offset_2 = offset_1; + offset_1 = tmpOff; + } /* swap offset_2 <=> offset_1 */ + hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip - base); + hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip - base); + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength - MINMATCH); + ip += rLength; + anchor = ip; + continue; /* faster when present ... (?) */ + } + } + } + + /* save reps for next block */ + cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved; + cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_doubleFast(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + const U32 mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 7); return; + } +} + +static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *const hashLong = ctx->hashTable; + U32 const hBitsL = ctx->params.cParams.hashLog; + U32 *const hashSmall = ctx->chainTable; + U32 const 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 curr = (U32)(ip - base); + const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */ + const BYTE *repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *repMatch = repBase + repIndex; + size_t mLength; + hashSmall[hSmall] = hashLong[hLong] = curr; /* update hash table */ + + if ((((U32)((dictLimit - 1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex)) && + (ZSTD_read32(repMatch) == ZSTD_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) && (ZSTD_read64(matchLong) == ZSTD_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 = curr - 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) && (ZSTD_read32(match) == ZSTD_read32(ip))) { + size_t const h3 = ZSTD_hashPtr(ip + 1, hBitsL, 8); + U32 const matchIndex3 = hashLong[h3]; + const BYTE *const match3Base = matchIndex3 < dictLimit ? dictBase : base; + const BYTE *match3 = match3Base + matchIndex3; + U32 offset; + hashLong[h3] = curr + 1; + if ((matchIndex3 > lowestIndex) && (ZSTD_read64(match3) == ZSTD_read64(ip + 1))) { + const BYTE *matchEnd = matchIndex3 < dictLimit ? dictEnd : iend; + const BYTE *lowMatchPtr = matchIndex3 < dictLimit ? dictStart : lowPrefixPtr; + mLength = ZSTD_count_2segments(ip + 9, match3 + 8, iend, matchEnd, lowPrefixPtr) + 8; + ip++; + offset = curr + 1 - matchIndex3; + while (((ip > anchor) & (match3 > lowMatchPtr)) && (ip[-1] == match3[-1])) { + ip--; + match3--; + mLength++; + } /* catch up */ + } else { + const BYTE *matchEnd = matchIndex < dictLimit ? dictEnd : iend; + const BYTE *lowMatchPtr = matchIndex < dictLimit ? dictStart : lowPrefixPtr; + mLength = ZSTD_count_2segments(ip + 4, match + 4, iend, matchEnd, lowPrefixPtr) + 4; + offset = curr - matchIndex; + while (((ip > anchor) & (match > lowMatchPtr)) && (ip[-1] == match[-1])) { + ip--; + match--; + mLength++; + } /* catch up */ + } + offset_2 = offset_1; + offset_1 = offset; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH); + + } else { + ip += ((ip - anchor) >> g_searchStrength) + 1; + continue; + } + } + + /* found a match : store it */ + ip += mLength; + anchor = ip; + + if (ip <= ilimit) { + /* Fill Table */ + hashSmall[ZSTD_hashPtr(base + curr + 2, hBitsS, mls)] = curr + 2; + hashLong[ZSTD_hashPtr(base + curr + 2, hBitsL, 8)] = curr + 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 curr2 = (U32)(ip - base); + U32 const repIndex2 = curr2 - offset_2; + const BYTE *repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2; + if ((((U32)((dictLimit - 1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */ + && (ZSTD_read32(repMatch2) == ZSTD_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)] = curr2; + hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = curr2; + ip += repLength2; + anchor = ip; + continue; + } + break; + } + } + } + + /* save reps for next block */ + ctx->repToConfirm[0] = offset_1; + ctx->repToConfirm[1] = offset_2; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_doubleFast_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + U32 const mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 7); return; + } +} + +/*-************************************* +* Binary Tree search +***************************************/ +/** ZSTD_insertBt1() : add one or multiple positions to tree. +* ip : assumed <= iend-8 . +* @return : nb of positions added */ +static U32 ZSTD_insertBt1(ZSTD_CCtx *zc, const BYTE *const ip, const U32 mls, const BYTE *const iend, U32 nbCompares, U32 extDict) +{ + U32 *const hashTable = zc->hashTable; + U32 const hashLog = zc->params.cParams.hashLog; + size_t const h = ZSTD_hashPtr(ip, hashLog, mls); + U32 *const bt = zc->chainTable; + U32 const btLog = zc->params.cParams.chainLog - 1; + U32 const btMask = (1 << btLog) - 1; + U32 matchIndex = hashTable[h]; + size_t commonLengthSmaller = 0, commonLengthLarger = 0; + const BYTE *const base = zc->base; + const BYTE *const dictBase = zc->dictBase; + const U32 dictLimit = zc->dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const BYTE *match; + const U32 curr = (U32)(ip - base); + const U32 btLow = btMask >= curr ? 0 : curr - btMask; + U32 *smallerPtr = bt + 2 * (curr & btMask); + U32 *largerPtr = smallerPtr + 1; + U32 dummy32; /* to be nullified at the end */ + U32 const windowLow = zc->lowLimit; + U32 matchEndIdx = curr + 8; + size_t bestLength = 8; + + hashTable[h] = curr; /* Update Hash Table */ + + while (nbCompares-- && (matchIndex > windowLow)) { + U32 *const nextPtr = bt + 2 * (matchIndex & btMask); + size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ + + 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 curr */ + *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 curr) */ + } else { + /* match is larger than curr */ + *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 > curr + 8) + return matchEndIdx - curr - 8; + return 1; +} + +static size_t ZSTD_insertBtAndFindBestMatch(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, size_t *offsetPtr, U32 nbCompares, const U32 mls, + U32 extDict) +{ + U32 *const hashTable = zc->hashTable; + U32 const hashLog = zc->params.cParams.hashLog; + size_t const h = ZSTD_hashPtr(ip, hashLog, mls); + U32 *const bt = zc->chainTable; + U32 const btLog = zc->params.cParams.chainLog - 1; + U32 const btMask = (1 << btLog) - 1; + U32 matchIndex = hashTable[h]; + size_t commonLengthSmaller = 0, commonLengthLarger = 0; + const BYTE *const base = zc->base; + const BYTE *const dictBase = zc->dictBase; + const U32 dictLimit = zc->dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const U32 curr = (U32)(ip - base); + const U32 btLow = btMask >= curr ? 0 : curr - btMask; + const U32 windowLow = zc->lowLimit; + U32 *smallerPtr = bt + 2 * (curr & btMask); + U32 *largerPtr = bt + 2 * (curr & btMask) + 1; + U32 matchEndIdx = curr + 8; + U32 dummy32; /* to be nullified at the end */ + size_t bestLength = 0; + + hashTable[h] = curr; /* Update Hash Table */ + + while (nbCompares-- && (matchIndex > windowLow)) { + U32 *const nextPtr = bt + 2 * (matchIndex & btMask); + size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ + const BYTE *match; + + if ((!extDict) || (matchIndex + matchLength >= dictLimit)) { + match = base + matchIndex; + if (match[matchLength] == ip[matchLength]) + matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iend) + 1; + } else { + match = dictBase + matchIndex; + matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iend, dictEnd, prefixStart); + if (matchIndex + matchLength >= dictLimit) + match = base + matchIndex; /* to prepare for next usage of match[matchLength] */ + } + + if (matchLength > bestLength) { + if (matchLength > matchEndIdx - matchIndex) + matchEndIdx = matchIndex + (U32)matchLength; + if ((4 * (int)(matchLength - bestLength)) > (int)(ZSTD_highbit32(curr - matchIndex + 1) - ZSTD_highbit32((U32)offsetPtr[0] + 1))) + bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + curr - 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 curr */ + *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 curr) */ + } else { + /* match is larger than curr */ + *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 > curr + 8) ? matchEndIdx - 8 : curr + 1; + return bestLength; +} + +static void ZSTD_updateTree(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, const U32 nbCompares, const U32 mls) +{ + const BYTE *const base = zc->base; + const U32 target = (U32)(ip - base); + U32 idx = zc->nextToUpdate; + + while (idx < target) + idx += ZSTD_insertBt1(zc, base + idx, mls, iend, nbCompares, 0); +} + +/** ZSTD_BtFindBestMatch() : Tree updater, providing best match */ +static size_t ZSTD_BtFindBestMatch(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 mls) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 0); +} + +static size_t ZSTD_BtFindBestMatch_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 matchLengthSearch) +{ + switch (matchLengthSearch) { + default: /* includes case 3 */ + case 4: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4); + case 5: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5); + case 7: + case 6: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6); + } +} + +static void ZSTD_updateTree_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, const U32 nbCompares, const U32 mls) +{ + const BYTE *const base = zc->base; + const U32 target = (U32)(ip - base); + U32 idx = zc->nextToUpdate; + + while (idx < target) + idx += ZSTD_insertBt1(zc, base + idx, mls, iend, nbCompares, 1); +} + +/** Tree updater, providing best match */ +static size_t ZSTD_BtFindBestMatch_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, + const U32 mls) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 1); +} + +static size_t ZSTD_BtFindBestMatch_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, + const U32 matchLengthSearch) +{ + switch (matchLengthSearch) { + default: /* includes case 3 */ + case 4: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4); + case 5: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5); + case 7: + case 6: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6); + } +} + +/* ********************************* +* Hash Chain +***********************************/ +#define NEXT_IN_CHAIN(d, mask) chainTable[(d)&mask] + +/* Update chains up to ip (excluded) + Assumption : always within prefix (i.e. not within extDict) */ +FORCE_INLINE +U32 ZSTD_insertAndFindFirstIndex(ZSTD_CCtx *zc, const BYTE *ip, U32 mls) +{ + U32 *const hashTable = zc->hashTable; + const U32 hashLog = zc->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)]; +} + +/* inlining is important to hardwire a hot branch (template emulation) */ +FORCE_INLINE +size_t ZSTD_HcFindBestMatch_generic(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 mls, + const U32 extDict) +{ + U32 *const chainTable = zc->chainTable; + const U32 chainSize = (1 << zc->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 curr = (U32)(ip - base); + const U32 minChain = curr > chainSize ? curr - 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 currMl = 0; + if ((!extDict) || matchIndex >= dictLimit) { + match = base + matchIndex; + if (match[ml] == ip[ml]) /* potentially better */ + currMl = ZSTD_count(ip, match, iLimit); + } else { + match = dictBase + matchIndex; + if (ZSTD_read32(match) == ZSTD_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */ + currMl = ZSTD_count_2segments(ip + EQUAL_READ32, match + EQUAL_READ32, iLimit, dictEnd, prefixStart) + EQUAL_READ32; + } + + /* save best solution */ + if (currMl > ml) { + ml = currMl; + *offsetPtr = curr - matchIndex + ZSTD_REP_MOVE; + if (ip + currMl == 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: /* includes case 3 */ + case 4: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 0); + case 5: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 0); + case 7: + case 6: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 0); + } +} + +FORCE_INLINE size_t ZSTD_HcFindBestMatch_extDict_selectMLS(ZSTD_CCtx *zc, const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, + const U32 matchLengthSearch) +{ + switch (matchLengthSearch) { + default: /* includes case 3 */ + case 4: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 1); + case 5: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 1); + case 7: + case 6: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 1); + } +} + +/* ******************************* +* Common parser - lazy strategy +*********************************/ +FORCE_INLINE +void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 searchMethod, const U32 depth) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base + ctx->dictLimit; + + U32 const maxSearches = 1 << ctx->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) & (ZSTD_read32(ip + 1) == ZSTD_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) & (ZSTD_read32(ip) == ZSTD_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) & (ZSTD_read32(ip) == ZSTD_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 */ + } + + /* NOTE: + * start[-offset+ZSTD_REP_MOVE-1] is undefined behavior. + * (-offset+ZSTD_REP_MOVE-1) is unsigned, and is added to start, which + * overflows the pointer, which is undefined behavior. + */ + /* catch up */ + if (offset) { + while ((start > anchor) && (start > base + offset - ZSTD_REP_MOVE) && + (start[-1] == (start-offset+ZSTD_REP_MOVE)[-1])) /* only search for offset within prefix */ + { + start--; + matchLength++; + } + offset_2 = offset_1; + offset_1 = (U32)(offset - ZSTD_REP_MOVE); + } + + /* store sequence */ +_storeSequence: + { + size_t const litLength = start - anchor; + ZSTD_storeSeq(seqStorePtr, litLength, anchor, (U32)offset, matchLength - MINMATCH); + anchor = ip = start + matchLength; + } + + /* check immediate repcode */ + while ((ip <= ilimit) && ((offset_2 > 0) & (ZSTD_read32(ip) == ZSTD_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->repToConfirm[0] = offset_1 ? offset_1 : savedOffset; + ctx->repToConfirm[1] = offset_2 ? offset_2 : savedOffset; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_btlazy2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 1, 2); } + +static void ZSTD_compressBlock_lazy2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 2); } + +static void ZSTD_compressBlock_lazy(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 1); } + +static void ZSTD_compressBlock_greedy(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 0); } + +FORCE_INLINE +void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 searchMethod, const U32 depth) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base; + const U32 dictLimit = ctx->dictLimit; + const U32 lowestIndex = ctx->lowLimit; + const BYTE *const prefixStart = base + dictLimit; + const BYTE *const dictBase = ctx->dictBase; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const dictStart = dictBase + ctx->lowLimit; + + const U32 maxSearches = 1 << ctx->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 curr = (U32)(ip - base); + + /* check repCode */ + { + const U32 repIndex = (U32)(curr + 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 (ZSTD_read32(ip + 1) == ZSTD_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++; + curr++; + /* check repCode */ + if (offset) { + const U32 repIndex = (U32)(curr - 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 (ZSTD_read32(ip) == ZSTD_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++; + curr++; + /* check repCode */ + if (offset) { + const U32 repIndex = (U32)(curr - 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 (ZSTD_read32(ip) == ZSTD_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 (ZSTD_read32(ip) == ZSTD_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->repToConfirm[0] = offset_1; + ctx->repToConfirm[1] = offset_2; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +void ZSTD_compressBlock_greedy_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 0); } + +static void ZSTD_compressBlock_lazy_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 1); +} + +static void ZSTD_compressBlock_lazy2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 2); +} + +static void ZSTD_compressBlock_btlazy2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 1, 2); +} + +/* The optimal parser */ +#include "zstd_opt.h" + +static void ZSTD_compressBlock_btopt(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 0); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +static void ZSTD_compressBlock_btopt2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 1); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +static void ZSTD_compressBlock_btopt_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 0); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +static void ZSTD_compressBlock_btopt2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 1); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +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][8] = { + {ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy, ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2, + ZSTD_compressBlock_btlazy2, ZSTD_compressBlock_btopt, ZSTD_compressBlock_btopt2}, + {ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict, ZSTD_compressBlock_lazy_extDict, + ZSTD_compressBlock_lazy2_extDict, ZSTD_compressBlock_btlazy2_extDict, ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btopt2_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); + const BYTE *const base = zc->base; + const BYTE *const istart = (const BYTE *)src; + const U32 curr = (U32)(istart - base); + if (srcSize < MIN_CBLOCK_SIZE + ZSTD_blockHeaderSize + 1) + return 0; /* don't even attempt compression below a certain srcSize */ + ZSTD_resetSeqStore(&(zc->seqStore)); + if (curr > zc->nextToUpdate + 384) + zc->nextToUpdate = curr - MIN(192, (U32)(curr - zc->nextToUpdate - 384)); /* update tree not updated after finding very long rep matches */ + blockCompressor(zc, src, srcSize); + return ZSTD_compressSequences(zc, dst, dstCapacity, srcSize); +} + +/*! ZSTD_compress_generic() : +* Compress a chunk of data into one or multiple blocks. +* All blocks will be terminated, all input will be consumed. +* Function will issue an error if there is not enough `dstCapacity` to hold the compressed content. +* Frame is supposed already started (header already produced) +* @return : compressed size, or an error code +*/ +static size_t ZSTD_compress_generic(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, U32 lastFrameChunk) +{ + size_t blockSize = cctx->blockSize; + size_t remaining = srcSize; + const BYTE *ip = (const BYTE *)src; + BYTE *const ostart = (BYTE *)dst; + BYTE *op = ostart; + U32 const maxDist = 1 << cctx->params.cParams.windowLog; + + if (cctx->params.fParams.checksumFlag && srcSize) + xxh64_update(&cctx->xxhState, src, srcSize); + + while (remaining) { + U32 const lastBlock = lastFrameChunk & (blockSize >= remaining); + size_t cSize; + + if (dstCapacity < ZSTD_blockHeaderSize + MIN_CBLOCK_SIZE) + return ERROR(dstSize_tooSmall); /* not enough space to store compressed block */ + if (remaining < blockSize) + blockSize = remaining; + + /* preemptive overflow correction */ + if (cctx->lowLimit > (3U << 29)) { + U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->params.cParams.hashLog, cctx->params.cParams.strategy)) - 1; + U32 const curr = (U32)(ip - cctx->base); + U32 const newCurr = (curr & cycleMask) + (1 << cctx->params.cParams.windowLog); + U32 const correction = curr - newCurr; + ZSTD_STATIC_ASSERT(ZSTD_WINDOWLOG_MAX_64 <= 30); + ZSTD_reduceIndex(cctx, correction); + cctx->base += correction; + cctx->dictBase += correction; + cctx->lowLimit -= correction; + cctx->dictLimit -= correction; + if (cctx->nextToUpdate < correction) + cctx->nextToUpdate = 0; + else + cctx->nextToUpdate -= correction; + } + + if ((U32)(ip + blockSize - cctx->base) > cctx->loadedDictEnd + maxDist) { + /* enforce maxDist */ + U32 const newLowLimit = (U32)(ip + blockSize - cctx->base) - maxDist; + if (cctx->lowLimit < newLowLimit) + cctx->lowLimit = newLowLimit; + if (cctx->dictLimit < cctx->lowLimit) + cctx->dictLimit = cctx->lowLimit; + } + + cSize = ZSTD_compressBlock_internal(cctx, op + ZSTD_blockHeaderSize, dstCapacity - ZSTD_blockHeaderSize, ip, blockSize); + if (ZSTD_isError(cSize)) + return cSize; + + if (cSize == 0) { /* block is not compressible */ + U32 const cBlockHeader24 = lastBlock + (((U32)bt_raw) << 1) + (U32)(blockSize << 3); + if (blockSize + ZSTD_blockHeaderSize > dstCapacity) + return ERROR(dstSize_tooSmall); + ZSTD_writeLE32(op, cBlockHeader24); /* no pb, 4th byte will be overwritten */ + memcpy(op + ZSTD_blockHeaderSize, ip, blockSize); + cSize = ZSTD_blockHeaderSize + blockSize; + } else { + U32 const cBlockHeader24 = lastBlock + (((U32)bt_compressed) << 1) + (U32)(cSize << 3); + ZSTD_writeLE24(op, cBlockHeader24); + cSize += ZSTD_blockHeaderSize; + } + + remaining -= blockSize; + dstCapacity -= cSize; + ip += blockSize; + op += cSize; + } + + if (lastFrameChunk && (op > ostart)) + cctx->stage = ZSTDcs_ending; + return op - ostart; +} + +static size_t ZSTD_writeFrameHeader(void *dst, size_t dstCapacity, ZSTD_parameters params, U64 pledgedSrcSize, U32 dictID) +{ + BYTE *const op = (BYTE *)dst; + U32 const 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); + BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3); + U32 const fcsCode = + params.fParams.contentSizeFlag ? (pledgedSrcSize >= 256) + (pledgedSrcSize >= 65536 + 256) + (pledgedSrcSize >= 0xFFFFFFFFU) : 0; /* 0-3 */ + BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag << 2) + (singleSegment << 5) + (fcsCode << 6)); + size_t pos; + + if (dstCapacity < ZSTD_frameHeaderSize_max) + return ERROR(dstSize_tooSmall); + + ZSTD_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: + ZSTD_writeLE16(op + pos, (U16)dictID); + pos += 2; + break; + case 3: + ZSTD_writeLE32(op + pos, dictID); + pos += 4; + break; + } + switch (fcsCode) { + default: /* impossible */ + case 0: + if (singleSegment) + op[pos++] = (BYTE)(pledgedSrcSize); + break; + case 1: + ZSTD_writeLE16(op + pos, (U16)(pledgedSrcSize - 256)); + pos += 2; + break; + case 2: + ZSTD_writeLE32(op + pos, (U32)(pledgedSrcSize)); + pos += 4; + break; + case 3: + ZSTD_writeLE64(op + pos, (U64)(pledgedSrcSize)); + pos += 8; + break; + } + return pos; +} + +static size_t ZSTD_compressContinue_internal(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, U32 frame, U32 lastFrameChunk) +{ + const BYTE *const ip = (const BYTE *)src; + size_t fhSize = 0; + + if (cctx->stage == ZSTDcs_created) + return ERROR(stage_wrong); /* missing init (ZSTD_compressBegin) */ + + if (frame && (cctx->stage == ZSTDcs_init)) { + fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, cctx->frameContentSize, cctx->dictID); + if (ZSTD_isError(fhSize)) + return fhSize; + dstCapacity -= fhSize; + dst = (char *)dst + fhSize; + cctx->stage = ZSTDcs_ongoing; + } + + /* Check if blocks follow each other */ + if (src != cctx->nextSrc) { + /* not contiguous */ + ptrdiff_t const delta = cctx->nextSrc - ip; + cctx->lowLimit = cctx->dictLimit; + cctx->dictLimit = (U32)(cctx->nextSrc - cctx->base); + cctx->dictBase = cctx->base; + cctx->base -= delta; + cctx->nextToUpdate = cctx->dictLimit; + if (cctx->dictLimit - cctx->lowLimit < HASH_READ_SIZE) + cctx->lowLimit = cctx->dictLimit; /* too small extDict */ + } + + /* if input and dictionary overlap : reduce dictionary (area presumed modified by input) */ + if ((ip + srcSize > cctx->dictBase + cctx->lowLimit) & (ip < cctx->dictBase + cctx->dictLimit)) { + ptrdiff_t const highInputIdx = (ip + srcSize) - cctx->dictBase; + U32 const lowLimitMax = (highInputIdx > (ptrdiff_t)cctx->dictLimit) ? cctx->dictLimit : (U32)highInputIdx; + cctx->lowLimit = lowLimitMax; + } + + cctx->nextSrc = ip + srcSize; + + if (srcSize) { + size_t const cSize = frame ? ZSTD_compress_generic(cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) + : ZSTD_compressBlock_internal(cctx, dst, dstCapacity, src, srcSize); + if (ZSTD_isError(cSize)) + return cSize; + return cSize + fhSize; + } else + return fhSize; +} + +size_t ZSTD_compressContinue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1, 0); +} + +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); + return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 0, 0); +} + +/*! ZSTD_loadDictionaryContent() : + * @return : 0, or an error code + */ +static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx *zc, const void *src, size_t srcSize) +{ + const BYTE *const ip = (const BYTE *)src; + const BYTE *const iend = ip + srcSize; + + /* input becomes curr prefix */ + zc->lowLimit = zc->dictLimit; + zc->dictLimit = (U32)(zc->nextSrc - zc->base); + zc->dictBase = zc->base; + zc->base += ip - zc->nextSrc; + zc->nextToUpdate = zc->dictLimit; + zc->loadedDictEnd = zc->forceWindow ? 0 : (U32)(iend - zc->base); + + zc->nextSrc = iend; + if (srcSize <= HASH_READ_SIZE) + return 0; + + switch (zc->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: + if (srcSize >= HASH_READ_SIZE) + ZSTD_insertAndFindFirstIndex(zc, iend - HASH_READ_SIZE, zc->params.cParams.searchLength); + break; + + case ZSTD_btlazy2: + case ZSTD_btopt: + case ZSTD_btopt2: + if (srcSize >= HASH_READ_SIZE) + ZSTD_updateTree(zc, iend - HASH_READ_SIZE, iend, 1 << zc->params.cParams.searchLog, zc->params.cParams.searchLength); + break; + + default: + return ERROR(GENERIC); /* strategy doesn't exist; impossible */ + } + + zc->nextToUpdate = (U32)(iend - zc->base); + return 0; +} + +/* Dictionaries that assign zero probability to symbols that show up causes problems + when FSE encoding. Refuse dictionaries that assign zero probability to symbols + that we may encounter during compression. + NOTE: This behavior is not standard and could be improved in the future. */ +static size_t ZSTD_checkDictNCount(short *normalizedCounter, unsigned dictMaxSymbolValue, unsigned maxSymbolValue) +{ + U32 s; + if (dictMaxSymbolValue < maxSymbolValue) + return ERROR(dictionary_corrupted); + for (s = 0; s <= maxSymbolValue; ++s) { + if (normalizedCounter[s] == 0) + return ERROR(dictionary_corrupted); + } + return 0; +} + +/* Dictionary format : + * See : + * https://github.com/facebook/zstd/blob/master/doc/zstd_compression_format.md#dictionary-format + */ +/*! ZSTD_loadZstdDictionary() : + * @return : 0, or an error code + * assumptions : magic number supposed already checked + * dictSize supposed > 8 + */ +static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx *cctx, const void *dict, size_t dictSize) +{ + const BYTE *dictPtr = (const BYTE *)dict; + const BYTE *const dictEnd = dictPtr + dictSize; + short offcodeNCount[MaxOff + 1]; + unsigned offcodeMaxValue = MaxOff; + + dictPtr += 4; /* skip magic number */ + cctx->dictID = cctx->params.fParams.noDictIDFlag ? 0 : ZSTD_readLE32(dictPtr); + dictPtr += 4; + + { + size_t const hufHeaderSize = HUF_readCTable_wksp(cctx->hufTable, 255, dictPtr, dictEnd - dictPtr, cctx->tmpCounters, sizeof(cctx->tmpCounters)); + if (HUF_isError(hufHeaderSize)) + return ERROR(dictionary_corrupted); + dictPtr += hufHeaderSize; + } + + { + unsigned offcodeLog; + size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(offcodeHeaderSize)) + return ERROR(dictionary_corrupted); + if (offcodeLog > OffFSELog) + return ERROR(dictionary_corrupted); + /* Defer checking offcodeMaxValue because we need to know the size of the dictionary content */ + CHECK_E(FSE_buildCTable_wksp(cctx->offcodeCTable, offcodeNCount, offcodeMaxValue, offcodeLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)), + dictionary_corrupted); + dictPtr += offcodeHeaderSize; + } + + { + short matchlengthNCount[MaxML + 1]; + unsigned matchlengthMaxValue = MaxML, matchlengthLog; + size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(matchlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (matchlengthLog > MLFSELog) + return ERROR(dictionary_corrupted); + /* Every match length code must have non-zero probability */ + CHECK_F(ZSTD_checkDictNCount(matchlengthNCount, matchlengthMaxValue, MaxML)); + CHECK_E( + FSE_buildCTable_wksp(cctx->matchlengthCTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)), + dictionary_corrupted); + dictPtr += matchlengthHeaderSize; + } + + { + short litlengthNCount[MaxLL + 1]; + unsigned litlengthMaxValue = MaxLL, litlengthLog; + size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(litlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (litlengthLog > LLFSELog) + return ERROR(dictionary_corrupted); + /* Every literal length code must have non-zero probability */ + CHECK_F(ZSTD_checkDictNCount(litlengthNCount, litlengthMaxValue, MaxLL)); + CHECK_E(FSE_buildCTable_wksp(cctx->litlengthCTable, litlengthNCount, litlengthMaxValue, litlengthLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)), + dictionary_corrupted); + dictPtr += litlengthHeaderSize; + } + + if (dictPtr + 12 > dictEnd) + return ERROR(dictionary_corrupted); + cctx->rep[0] = ZSTD_readLE32(dictPtr + 0); + cctx->rep[1] = ZSTD_readLE32(dictPtr + 4); + cctx->rep[2] = ZSTD_readLE32(dictPtr + 8); + dictPtr += 12; + + { + size_t const dictContentSize = (size_t)(dictEnd - dictPtr); + U32 offcodeMax = MaxOff; + if (dictContentSize <= ((U32)-1) - 128 KB) { + U32 const maxOffset = (U32)dictContentSize + 128 KB; /* The maximum offset that must be supported */ + offcodeMax = ZSTD_highbit32(maxOffset); /* Calculate minimum offset code required to represent maxOffset */ + } + /* All offset values <= dictContentSize + 128 KB must be representable */ + CHECK_F(ZSTD_checkDictNCount(offcodeNCount, offcodeMaxValue, MIN(offcodeMax, MaxOff))); + /* All repCodes must be <= dictContentSize and != 0*/ + { + U32 u; + for (u = 0; u < 3; u++) { + if (cctx->rep[u] == 0) + return ERROR(dictionary_corrupted); + if (cctx->rep[u] > dictContentSize) + return ERROR(dictionary_corrupted); + } + } + + cctx->flagStaticTables = 1; + cctx->flagStaticHufTable = HUF_repeat_valid; + return ZSTD_loadDictionaryContent(cctx, dictPtr, dictContentSize); + } +} + +/** ZSTD_compress_insertDictionary() : +* @return : 0, or an error code */ +static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx *cctx, const void *dict, size_t dictSize) +{ + if ((dict == NULL) || (dictSize <= 8)) + return 0; + + /* dict as pure content */ + if ((ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC) || (cctx->forceRawDict)) + return ZSTD_loadDictionaryContent(cctx, dict, dictSize); + + /* dict as zstd dictionary */ + return ZSTD_loadZstdDictionary(cctx, dict, dictSize); +} + +/*! ZSTD_compressBegin_internal() : +* @return : 0, or an error code */ +static size_t ZSTD_compressBegin_internal(ZSTD_CCtx *cctx, const void *dict, size_t dictSize, ZSTD_parameters params, U64 pledgedSrcSize) +{ + ZSTD_compResetPolicy_e const crp = dictSize ? ZSTDcrp_fullReset : ZSTDcrp_continue; + CHECK_F(ZSTD_resetCCtx_advanced(cctx, params, pledgedSrcSize, crp)); + return ZSTD_compress_insertDictionary(cctx, 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 */ + CHECK_F(ZSTD_checkCParams(params.cParams)); + 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); + return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0); +} + +size_t ZSTD_compressBegin(ZSTD_CCtx *cctx, int compressionLevel) { return ZSTD_compressBegin_usingDict(cctx, NULL, 0, compressionLevel); } + +/*! ZSTD_writeEpilogue() : +* Ends a frame. +* @return : nb of bytes written into dst (or an error code) */ +static size_t ZSTD_writeEpilogue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity) +{ + BYTE *const ostart = (BYTE *)dst; + BYTE *op = ostart; + size_t fhSize = 0; + + if (cctx->stage == ZSTDcs_created) + return ERROR(stage_wrong); /* init missing */ + + /* special case : empty frame */ + if (cctx->stage == ZSTDcs_init) { + fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, 0, 0); + if (ZSTD_isError(fhSize)) + return fhSize; + dstCapacity -= fhSize; + op += fhSize; + cctx->stage = ZSTDcs_ongoing; + } + + if (cctx->stage != ZSTDcs_ending) { + /* write one last empty block, make it the "last" block */ + U32 const cBlockHeader24 = 1 /* last block */ + (((U32)bt_raw) << 1) + 0; + if (dstCapacity < 4) + return ERROR(dstSize_tooSmall); + ZSTD_writeLE32(op, cBlockHeader24); + op += ZSTD_blockHeaderSize; + dstCapacity -= ZSTD_blockHeaderSize; + } + + if (cctx->params.fParams.checksumFlag) { + U32 const checksum = (U32)xxh64_digest(&cctx->xxhState); + if (dstCapacity < 4) + return ERROR(dstSize_tooSmall); + ZSTD_writeLE32(op, checksum); + op += 4; + } + + cctx->stage = ZSTDcs_created; /* return to "created but no init" status */ + return op - ostart; +} + +size_t ZSTD_compressEnd(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t endResult; + size_t const cSize = ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1, 1); + if (ZSTD_isError(cSize)) + return cSize; + endResult = ZSTD_writeEpilogue(cctx, (char *)dst + cSize, dstCapacity - cSize); + if (ZSTD_isError(endResult)) + return endResult; + return cSize + endResult; +} + +static size_t ZSTD_compress_internal(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize, + ZSTD_parameters params) +{ + CHECK_F(ZSTD_compressBegin_internal(cctx, dict, dictSize, params, srcSize)); + return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize); +} + +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, + ZSTD_parameters params) +{ + 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, ZSTD_parameters params) +{ + return ZSTD_compress_internal(ctx, dst, dstCapacity, src, srcSize, NULL, 0, params); +} + +/* ===== Dictionary API ===== */ + +struct ZSTD_CDict_s { + void *dictBuffer; + const void *dictContent; + size_t dictContentSize; + ZSTD_CCtx *refContext; +}; /* typedef'd tp ZSTD_CDict within "zstd.h" */ + +size_t ZSTD_CDictWorkspaceBound(ZSTD_compressionParameters cParams) { return ZSTD_CCtxWorkspaceBound(cParams) + ZSTD_ALIGN(sizeof(ZSTD_CDict)); } + +static ZSTD_CDict *ZSTD_createCDict_advanced(const void *dictBuffer, size_t dictSize, unsigned byReference, ZSTD_parameters params, ZSTD_customMem customMem) +{ + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + { + ZSTD_CDict *const cdict = (ZSTD_CDict *)ZSTD_malloc(sizeof(ZSTD_CDict), customMem); + ZSTD_CCtx *const cctx = ZSTD_createCCtx_advanced(customMem); + + if (!cdict || !cctx) { + ZSTD_free(cdict, customMem); + ZSTD_freeCCtx(cctx); + return NULL; + } + + if ((byReference) || (!dictBuffer) || (!dictSize)) { + cdict->dictBuffer = NULL; + cdict->dictContent = dictBuffer; + } else { + void *const internalBuffer = ZSTD_malloc(dictSize, customMem); + if (!internalBuffer) { + ZSTD_free(cctx, customMem); + ZSTD_free(cdict, customMem); + return NULL; + } + memcpy(internalBuffer, dictBuffer, dictSize); + cdict->dictBuffer = internalBuffer; + cdict->dictContent = internalBuffer; + } + + { + size_t const errorCode = ZSTD_compressBegin_advanced(cctx, cdict->dictContent, dictSize, params, 0); + if (ZSTD_isError(errorCode)) { + ZSTD_free(cdict->dictBuffer, customMem); + ZSTD_free(cdict, customMem); + ZSTD_freeCCtx(cctx); + return NULL; + } + } + + cdict->refContext = cctx; + cdict->dictContentSize = dictSize; + return cdict; + } +} + +ZSTD_CDict *ZSTD_initCDict(const void *dict, size_t dictSize, ZSTD_parameters params, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + return ZSTD_createCDict_advanced(dict, dictSize, 1, params, stackMem); +} + +size_t ZSTD_freeCDict(ZSTD_CDict *cdict) +{ + if (cdict == NULL) + return 0; /* support free on NULL */ + { + ZSTD_customMem const cMem = cdict->refContext->customMem; + ZSTD_freeCCtx(cdict->refContext); + ZSTD_free(cdict->dictBuffer, cMem); + ZSTD_free(cdict, cMem); + return 0; + } +} + +static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict *cdict) { return ZSTD_getParamsFromCCtx(cdict->refContext); } + +size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx *cctx, const ZSTD_CDict *cdict, unsigned long long pledgedSrcSize) +{ + if (cdict->dictContentSize) + CHECK_F(ZSTD_copyCCtx(cctx, cdict->refContext, pledgedSrcSize)) + else { + ZSTD_parameters params = cdict->refContext->params; + params.fParams.contentSizeFlag = (pledgedSrcSize > 0); + CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, params, pledgedSrcSize)); + } + return 0; +} + +/*! ZSTD_compress_usingCDict() : +* Compression using a digested Dictionary. +* Faster startup than ZSTD_compress_usingDict(), recommended when same dictionary is used multiple times. +* Note that compression level is decided during dictionary creation */ +size_t ZSTD_compress_usingCDict(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_CDict *cdict) +{ + CHECK_F(ZSTD_compressBegin_usingCDict(cctx, cdict, srcSize)); + + if (cdict->refContext->params.fParams.contentSizeFlag == 1) { + cctx->params.fParams.contentSizeFlag = 1; + cctx->frameContentSize = srcSize; + } else { + cctx->params.fParams.contentSizeFlag = 0; + } + + return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize); +} + +/* ****************************************************************** +* Streaming +********************************************************************/ + +typedef enum { zcss_init, zcss_load, zcss_flush, zcss_final } ZSTD_cStreamStage; + +struct ZSTD_CStream_s { + ZSTD_CCtx *cctx; + ZSTD_CDict *cdictLocal; + const ZSTD_CDict *cdict; + char *inBuff; + size_t inBuffSize; + size_t inToCompress; + size_t inBuffPos; + size_t inBuffTarget; + size_t blockSize; + char *outBuff; + size_t outBuffSize; + size_t outBuffContentSize; + size_t outBuffFlushedSize; + ZSTD_cStreamStage stage; + U32 checksum; + U32 frameEnded; + U64 pledgedSrcSize; + U64 inputProcessed; + ZSTD_parameters params; + ZSTD_customMem customMem; +}; /* typedef'd to ZSTD_CStream within "zstd.h" */ + +size_t ZSTD_CStreamWorkspaceBound(ZSTD_compressionParameters cParams) +{ + size_t const inBuffSize = (size_t)1 << cParams.windowLog; + size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, inBuffSize); + size_t const outBuffSize = ZSTD_compressBound(blockSize) + 1; + + return ZSTD_CCtxWorkspaceBound(cParams) + ZSTD_ALIGN(sizeof(ZSTD_CStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize); +} + +ZSTD_CStream *ZSTD_createCStream_advanced(ZSTD_customMem customMem) +{ + ZSTD_CStream *zcs; + + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + zcs = (ZSTD_CStream *)ZSTD_malloc(sizeof(ZSTD_CStream), customMem); + if (zcs == NULL) + return NULL; + memset(zcs, 0, sizeof(ZSTD_CStream)); + memcpy(&zcs->customMem, &customMem, sizeof(ZSTD_customMem)); + zcs->cctx = ZSTD_createCCtx_advanced(customMem); + if (zcs->cctx == NULL) { + ZSTD_freeCStream(zcs); + return NULL; + } + return zcs; +} + +size_t ZSTD_freeCStream(ZSTD_CStream *zcs) +{ + if (zcs == NULL) + return 0; /* support free on NULL */ + { + ZSTD_customMem const cMem = zcs->customMem; + ZSTD_freeCCtx(zcs->cctx); + zcs->cctx = NULL; + ZSTD_freeCDict(zcs->cdictLocal); + zcs->cdictLocal = NULL; + ZSTD_free(zcs->inBuff, cMem); + zcs->inBuff = NULL; + ZSTD_free(zcs->outBuff, cMem); + zcs->outBuff = NULL; + ZSTD_free(zcs, cMem); + return 0; + } +} + +/*====== Initialization ======*/ + +size_t ZSTD_CStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; } +size_t ZSTD_CStreamOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */; } + +static size_t ZSTD_resetCStream_internal(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize) +{ + if (zcs->inBuffSize == 0) + return ERROR(stage_wrong); /* zcs has not been init at least once => can't reset */ + + if (zcs->cdict) + CHECK_F(ZSTD_compressBegin_usingCDict(zcs->cctx, zcs->cdict, pledgedSrcSize)) + else + CHECK_F(ZSTD_compressBegin_advanced(zcs->cctx, NULL, 0, zcs->params, pledgedSrcSize)); + + zcs->inToCompress = 0; + zcs->inBuffPos = 0; + zcs->inBuffTarget = zcs->blockSize; + zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0; + zcs->stage = zcss_load; + zcs->frameEnded = 0; + zcs->pledgedSrcSize = pledgedSrcSize; + zcs->inputProcessed = 0; + return 0; /* ready to go */ +} + +size_t ZSTD_resetCStream(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize) +{ + + zcs->params.fParams.contentSizeFlag = (pledgedSrcSize > 0); + + return ZSTD_resetCStream_internal(zcs, pledgedSrcSize); +} + +static size_t ZSTD_initCStream_advanced(ZSTD_CStream *zcs, const void *dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize) +{ + /* allocate buffers */ + { + size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog; + if (zcs->inBuffSize < neededInBuffSize) { + zcs->inBuffSize = neededInBuffSize; + ZSTD_free(zcs->inBuff, zcs->customMem); + zcs->inBuff = (char *)ZSTD_malloc(neededInBuffSize, zcs->customMem); + if (zcs->inBuff == NULL) + return ERROR(memory_allocation); + } + zcs->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize); + } + if (zcs->outBuffSize < ZSTD_compressBound(zcs->blockSize) + 1) { + zcs->outBuffSize = ZSTD_compressBound(zcs->blockSize) + 1; + ZSTD_free(zcs->outBuff, zcs->customMem); + zcs->outBuff = (char *)ZSTD_malloc(zcs->outBuffSize, zcs->customMem); + if (zcs->outBuff == NULL) + return ERROR(memory_allocation); + } + + if (dict && dictSize >= 8) { + ZSTD_freeCDict(zcs->cdictLocal); + zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize, 0, params, zcs->customMem); + if (zcs->cdictLocal == NULL) + return ERROR(memory_allocation); + zcs->cdict = zcs->cdictLocal; + } else + zcs->cdict = NULL; + + zcs->checksum = params.fParams.checksumFlag > 0; + zcs->params = params; + + return ZSTD_resetCStream_internal(zcs, pledgedSrcSize); +} + +ZSTD_CStream *ZSTD_initCStream(ZSTD_parameters params, unsigned long long pledgedSrcSize, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + ZSTD_CStream *const zcs = ZSTD_createCStream_advanced(stackMem); + if (zcs) { + size_t const code = ZSTD_initCStream_advanced(zcs, NULL, 0, params, pledgedSrcSize); + if (ZSTD_isError(code)) { + return NULL; + } + } + return zcs; +} + +ZSTD_CStream *ZSTD_initCStream_usingCDict(const ZSTD_CDict *cdict, unsigned long long pledgedSrcSize, void *workspace, size_t workspaceSize) +{ + ZSTD_parameters const params = ZSTD_getParamsFromCDict(cdict); + ZSTD_CStream *const zcs = ZSTD_initCStream(params, pledgedSrcSize, workspace, workspaceSize); + if (zcs) { + zcs->cdict = cdict; + if (ZSTD_isError(ZSTD_resetCStream_internal(zcs, pledgedSrcSize))) { + return NULL; + } + } + return zcs; +} + +/*====== Compression ======*/ + +typedef enum { zsf_gather, zsf_flush, zsf_end } ZSTD_flush_e; + +ZSTD_STATIC size_t ZSTD_limitCopy(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t const length = MIN(dstCapacity, srcSize); + memcpy(dst, src, length); + return length; +} + +static size_t ZSTD_compressStream_generic(ZSTD_CStream *zcs, void *dst, size_t *dstCapacityPtr, const void *src, size_t *srcSizePtr, ZSTD_flush_e const flush) +{ + U32 someMoreWork = 1; + const char *const istart = (const char *)src; + const char *const iend = istart + *srcSizePtr; + const char *ip = istart; + char *const ostart = (char *)dst; + char *const oend = ostart + *dstCapacityPtr; + char *op = ostart; + + while (someMoreWork) { + switch (zcs->stage) { + case zcss_init: + return ERROR(init_missing); /* call ZBUFF_compressInit() first ! */ + + case zcss_load: + /* complete inBuffer */ + { + size_t const toLoad = zcs->inBuffTarget - zcs->inBuffPos; + size_t const loaded = ZSTD_limitCopy(zcs->inBuff + zcs->inBuffPos, toLoad, ip, iend - ip); + zcs->inBuffPos += loaded; + ip += loaded; + if ((zcs->inBuffPos == zcs->inToCompress) || (!flush && (toLoad != loaded))) { + someMoreWork = 0; + break; /* not enough input to get a full block : stop there, wait for more */ + } + } + /* compress curr block (note : this stage cannot be stopped in the middle) */ + { + void *cDst; + size_t cSize; + size_t const iSize = zcs->inBuffPos - zcs->inToCompress; + size_t oSize = oend - op; + if (oSize >= ZSTD_compressBound(iSize)) + cDst = op; /* compress directly into output buffer (avoid flush stage) */ + else + cDst = zcs->outBuff, oSize = zcs->outBuffSize; + cSize = (flush == zsf_end) ? ZSTD_compressEnd(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize) + : ZSTD_compressContinue(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize); + if (ZSTD_isError(cSize)) + return cSize; + if (flush == zsf_end) + zcs->frameEnded = 1; + /* prepare next block */ + zcs->inBuffTarget = zcs->inBuffPos + zcs->blockSize; + if (zcs->inBuffTarget > zcs->inBuffSize) + zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize; /* note : inBuffSize >= blockSize */ + zcs->inToCompress = zcs->inBuffPos; + if (cDst == op) { + op += cSize; + break; + } /* no need to flush */ + zcs->outBuffContentSize = cSize; + zcs->outBuffFlushedSize = 0; + zcs->stage = zcss_flush; /* pass-through to flush stage */ + } + + case zcss_flush: { + size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize; + size_t const flushed = ZSTD_limitCopy(op, oend - op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush); + op += flushed; + zcs->outBuffFlushedSize += flushed; + if (toFlush != flushed) { + someMoreWork = 0; + break; + } /* dst too small to store flushed data : stop there */ + zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0; + zcs->stage = zcss_load; + break; + } + + case zcss_final: + someMoreWork = 0; /* do nothing */ + break; + + default: + return ERROR(GENERIC); /* impossible */ + } + } + + *srcSizePtr = ip - istart; + *dstCapacityPtr = op - ostart; + zcs->inputProcessed += *srcSizePtr; + if (zcs->frameEnded) + return 0; + { + size_t hintInSize = zcs->inBuffTarget - zcs->inBuffPos; + if (hintInSize == 0) + hintInSize = zcs->blockSize; + return hintInSize; + } +} + +size_t ZSTD_compressStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output, ZSTD_inBuffer *input) +{ + size_t sizeRead = input->size - input->pos; + size_t sizeWritten = output->size - output->pos; + size_t const result = + ZSTD_compressStream_generic(zcs, (char *)(output->dst) + output->pos, &sizeWritten, (const char *)(input->src) + input->pos, &sizeRead, zsf_gather); + input->pos += sizeRead; + output->pos += sizeWritten; + return result; +} + +/*====== Finalize ======*/ + +/*! ZSTD_flushStream() : +* @return : amount of data remaining to flush */ +size_t ZSTD_flushStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output) +{ + size_t srcSize = 0; + size_t sizeWritten = output->size - output->pos; + size_t const result = ZSTD_compressStream_generic(zcs, (char *)(output->dst) + output->pos, &sizeWritten, &srcSize, + &srcSize, /* use a valid src address instead of NULL */ + zsf_flush); + output->pos += sizeWritten; + if (ZSTD_isError(result)) + return result; + return zcs->outBuffContentSize - zcs->outBuffFlushedSize; /* remaining to flush */ +} + +size_t ZSTD_endStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output) +{ + BYTE *const ostart = (BYTE *)(output->dst) + output->pos; + BYTE *const oend = (BYTE *)(output->dst) + output->size; + BYTE *op = ostart; + + if ((zcs->pledgedSrcSize) && (zcs->inputProcessed != zcs->pledgedSrcSize)) + return ERROR(srcSize_wrong); /* pledgedSrcSize not respected */ + + if (zcs->stage != zcss_final) { + /* flush whatever remains */ + size_t srcSize = 0; + size_t sizeWritten = output->size - output->pos; + size_t const notEnded = + ZSTD_compressStream_generic(zcs, ostart, &sizeWritten, &srcSize, &srcSize, zsf_end); /* use a valid src address instead of NULL */ + size_t const remainingToFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize; + op += sizeWritten; + if (remainingToFlush) { + output->pos += sizeWritten; + return remainingToFlush + ZSTD_BLOCKHEADERSIZE /* final empty block */ + (zcs->checksum * 4); + } + /* create epilogue */ + zcs->stage = zcss_final; + zcs->outBuffContentSize = !notEnded ? 0 : ZSTD_compressEnd(zcs->cctx, zcs->outBuff, zcs->outBuffSize, NULL, + 0); /* write epilogue, including final empty block, into outBuff */ + } + + /* flush epilogue */ + { + size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize; + size_t const flushed = ZSTD_limitCopy(op, oend - op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush); + op += flushed; + zcs->outBuffFlushedSize += flushed; + output->pos += op - ostart; + if (toFlush == flushed) + zcs->stage = zcss_init; /* end reached */ + return toFlush - flushed; + } +} + +/*-===== 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 - never used */ + {19, 13, 14, 1, 7, 16, ZSTD_fast}, /* level 1 */ + {19, 15, 16, 1, 6, 16, ZSTD_fast}, /* level 2 */ + {20, 16, 17, 1, 5, 16, ZSTD_dfast}, /* level 3.*/ + {20, 18, 18, 1, 5, 16, ZSTD_dfast}, /* 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, 21, 22, 4, 5, 24, ZSTD_btopt}, /* level 17 */ + {23, 23, 22, 6, 5, 32, ZSTD_btopt}, /* level 18 */ + {23, 23, 22, 6, 3, 48, ZSTD_btopt}, /* level 19 */ + {25, 25, 23, 7, 3, 64, ZSTD_btopt2}, /* level 20 */ + {26, 26, 23, 7, 3, 256, ZSTD_btopt2}, /* level 21 */ + {27, 27, 25, 9, 3, 512, ZSTD_btopt2}, /* level 22 */ + }, + { + /* for srcSize <= 256 KB */ + /* W, C, H, S, L, T, strat */ + {0, 0, 0, 0, 0, 0, ZSTD_fast}, /* level 0 - not used */ + {18, 13, 14, 1, 6, 8, ZSTD_fast}, /* level 1 */ + {18, 14, 13, 1, 5, 8, ZSTD_dfast}, /* level 2 */ + {18, 16, 15, 1, 5, 8, ZSTD_dfast}, /* level 3 */ + {18, 15, 17, 1, 5, 8, ZSTD_greedy}, /* level 4.*/ + {18, 16, 17, 4, 5, 8, ZSTD_greedy}, /* level 5.*/ + {18, 16, 17, 3, 5, 8, ZSTD_lazy}, /* level 6.*/ + {18, 17, 17, 4, 4, 8, ZSTD_lazy}, /* level 7 */ + {18, 17, 17, 4, 4, 8, ZSTD_lazy2}, /* level 8 */ + {18, 17, 17, 5, 4, 8, ZSTD_lazy2}, /* level 9 */ + {18, 17, 17, 6, 4, 8, ZSTD_lazy2}, /* level 10 */ + {18, 18, 17, 6, 4, 8, ZSTD_lazy2}, /* level 11.*/ + {18, 18, 17, 7, 4, 8, ZSTD_lazy2}, /* level 12.*/ + {18, 19, 17, 6, 4, 8, ZSTD_btlazy2}, /* level 13 */ + {18, 18, 18, 4, 4, 16, ZSTD_btopt}, /* level 14.*/ + {18, 18, 18, 4, 3, 16, ZSTD_btopt}, /* level 15.*/ + {18, 19, 18, 6, 3, 32, ZSTD_btopt}, /* level 16.*/ + {18, 19, 18, 8, 3, 64, ZSTD_btopt}, /* level 17.*/ + {18, 19, 18, 9, 3, 128, ZSTD_btopt}, /* level 18.*/ + {18, 19, 18, 10, 3, 256, ZSTD_btopt}, /* level 19.*/ + {18, 19, 18, 11, 3, 512, ZSTD_btopt2}, /* level 20.*/ + {18, 19, 18, 12, 3, 512, ZSTD_btopt2}, /* level 21.*/ + {18, 19, 18, 13, 3, 512, ZSTD_btopt2}, /* 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_btopt2}, /* level 20.*/ + {17, 18, 17, 10, 3, 256, ZSTD_btopt2}, /* level 21.*/ + {17, 18, 17, 11, 3, 512, ZSTD_btopt2}, /* 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_btopt2}, /* level 20.*/ + {14, 15, 15, 9, 3, 256, ZSTD_btopt2}, /* level 21.*/ + {14, 15, 15, 10, 3, 256, ZSTD_btopt2}, /* 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 (ZSTD_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; +} + +EXPORT_SYMBOL(ZSTD_maxCLevel); +EXPORT_SYMBOL(ZSTD_compressBound); + +EXPORT_SYMBOL(ZSTD_CCtxWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initCCtx); +EXPORT_SYMBOL(ZSTD_compressCCtx); +EXPORT_SYMBOL(ZSTD_compress_usingDict); + +EXPORT_SYMBOL(ZSTD_CDictWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initCDict); +EXPORT_SYMBOL(ZSTD_compress_usingCDict); + +EXPORT_SYMBOL(ZSTD_CStreamWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initCStream); +EXPORT_SYMBOL(ZSTD_initCStream_usingCDict); +EXPORT_SYMBOL(ZSTD_resetCStream); +EXPORT_SYMBOL(ZSTD_compressStream); +EXPORT_SYMBOL(ZSTD_flushStream); +EXPORT_SYMBOL(ZSTD_endStream); +EXPORT_SYMBOL(ZSTD_CStreamInSize); +EXPORT_SYMBOL(ZSTD_CStreamOutSize); + +EXPORT_SYMBOL(ZSTD_getCParams); +EXPORT_SYMBOL(ZSTD_getParams); +EXPORT_SYMBOL(ZSTD_checkCParams); +EXPORT_SYMBOL(ZSTD_adjustCParams); + +EXPORT_SYMBOL(ZSTD_compressBegin); +EXPORT_SYMBOL(ZSTD_compressBegin_usingDict); +EXPORT_SYMBOL(ZSTD_compressBegin_advanced); +EXPORT_SYMBOL(ZSTD_copyCCtx); +EXPORT_SYMBOL(ZSTD_compressBegin_usingCDict); +EXPORT_SYMBOL(ZSTD_compressContinue); +EXPORT_SYMBOL(ZSTD_compressEnd); + +EXPORT_SYMBOL(ZSTD_getBlockSizeMax); +EXPORT_SYMBOL(ZSTD_compressBlock); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("Zstd Compressor"); |