mirror of
https://github.com/facebook/zstd.git
synced 2024-12-12 04:06:43 +08:00
fbd97f305a
* Mark all bufferless and block level functions as deprecated * Update documentation to suggest not using these functions * Add `_deprecated()` wrappers for functions that we use internally and call those instead
1128 lines
43 KiB
C
1128 lines
43 KiB
C
/*
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* Copyright (c) Meta Platforms, Inc. and affiliates.
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* All rights reserved.
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*
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* This source code is licensed under both the BSD-style license (found in the
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* LICENSE file in the root directory of this source tree) and the GPLv2 (found
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* in the COPYING file in the root directory of this source tree).
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* You may select, at your option, one of the above-listed licenses.
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*/
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/*-**************************************
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* Tuning parameters
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****************************************/
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#define MINRATIO 4 /* minimum nb of apparition to be selected in dictionary */
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#define ZDICT_MAX_SAMPLES_SIZE (2000U << 20)
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#define ZDICT_MIN_SAMPLES_SIZE (ZDICT_CONTENTSIZE_MIN * MINRATIO)
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/*-**************************************
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* Compiler Options
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****************************************/
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/* Unix Large Files support (>4GB) */
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#define _FILE_OFFSET_BITS 64
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#if (defined(__sun__) && (!defined(__LP64__))) /* Sun Solaris 32-bits requires specific definitions */
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# ifndef _LARGEFILE_SOURCE
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# define _LARGEFILE_SOURCE
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# endif
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#elif ! defined(__LP64__) /* No point defining Large file for 64 bit */
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# ifndef _LARGEFILE64_SOURCE
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# define _LARGEFILE64_SOURCE
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# endif
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#endif
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/*-*************************************
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* Dependencies
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***************************************/
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#include <stdlib.h> /* malloc, free */
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#include <string.h> /* memset */
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#include <stdio.h> /* fprintf, fopen, ftello64 */
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#include <time.h> /* clock */
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#ifndef ZDICT_STATIC_LINKING_ONLY
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# define ZDICT_STATIC_LINKING_ONLY
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#endif
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#include "../common/mem.h" /* read */
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#include "../common/fse.h" /* FSE_normalizeCount, FSE_writeNCount */
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#include "../common/huf.h" /* HUF_buildCTable, HUF_writeCTable */
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#include "../common/zstd_internal.h" /* includes zstd.h */
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#include "../common/xxhash.h" /* XXH64 */
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#include "../compress/zstd_compress_internal.h" /* ZSTD_loadCEntropy() */
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#include "../zdict.h"
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#include "divsufsort.h"
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#include "../common/bits.h" /* ZSTD_NbCommonBytes */
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/*-*************************************
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* Constants
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***************************************/
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#define KB *(1 <<10)
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#define MB *(1 <<20)
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#define GB *(1U<<30)
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#define DICTLISTSIZE_DEFAULT 10000
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#define NOISELENGTH 32
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static const U32 g_selectivity_default = 9;
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/*-*************************************
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* Console display
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***************************************/
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#undef DISPLAY
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#define DISPLAY(...) { fprintf(stderr, __VA_ARGS__); fflush( stderr ); }
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#undef DISPLAYLEVEL
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#define DISPLAYLEVEL(l, ...) if (notificationLevel>=l) { DISPLAY(__VA_ARGS__); } /* 0 : no display; 1: errors; 2: default; 3: details; 4: debug */
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static clock_t ZDICT_clockSpan(clock_t nPrevious) { return clock() - nPrevious; }
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static void ZDICT_printHex(const void* ptr, size_t length)
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{
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const BYTE* const b = (const BYTE*)ptr;
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size_t u;
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for (u=0; u<length; u++) {
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BYTE c = b[u];
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if (c<32 || c>126) c = '.'; /* non-printable char */
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DISPLAY("%c", c);
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}
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}
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/*-********************************************************
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* Helper functions
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**********************************************************/
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unsigned ZDICT_isError(size_t errorCode) { return ERR_isError(errorCode); }
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const char* ZDICT_getErrorName(size_t errorCode) { return ERR_getErrorName(errorCode); }
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unsigned ZDICT_getDictID(const void* dictBuffer, size_t dictSize)
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{
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if (dictSize < 8) return 0;
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if (MEM_readLE32(dictBuffer) != ZSTD_MAGIC_DICTIONARY) return 0;
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return MEM_readLE32((const char*)dictBuffer + 4);
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}
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size_t ZDICT_getDictHeaderSize(const void* dictBuffer, size_t dictSize)
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{
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size_t headerSize;
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if (dictSize <= 8 || MEM_readLE32(dictBuffer) != ZSTD_MAGIC_DICTIONARY) return ERROR(dictionary_corrupted);
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{ ZSTD_compressedBlockState_t* bs = (ZSTD_compressedBlockState_t*)malloc(sizeof(ZSTD_compressedBlockState_t));
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U32* wksp = (U32*)malloc(HUF_WORKSPACE_SIZE);
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if (!bs || !wksp) {
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headerSize = ERROR(memory_allocation);
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} else {
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ZSTD_reset_compressedBlockState(bs);
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headerSize = ZSTD_loadCEntropy(bs, wksp, dictBuffer, dictSize);
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}
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free(bs);
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free(wksp);
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}
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return headerSize;
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}
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/*-********************************************************
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* Dictionary training functions
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**********************************************************/
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/*! ZDICT_count() :
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Count the nb of common bytes between 2 pointers.
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Note : this function presumes end of buffer followed by noisy guard band.
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*/
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static size_t ZDICT_count(const void* pIn, const void* pMatch)
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{
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const char* const pStart = (const char*)pIn;
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for (;;) {
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size_t const diff = MEM_readST(pMatch) ^ MEM_readST(pIn);
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if (!diff) {
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pIn = (const char*)pIn+sizeof(size_t);
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pMatch = (const char*)pMatch+sizeof(size_t);
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continue;
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}
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pIn = (const char*)pIn+ZSTD_NbCommonBytes(diff);
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return (size_t)((const char*)pIn - pStart);
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}
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}
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typedef struct {
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U32 pos;
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U32 length;
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U32 savings;
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} dictItem;
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static void ZDICT_initDictItem(dictItem* d)
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{
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d->pos = 1;
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d->length = 0;
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d->savings = (U32)(-1);
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}
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#define LLIMIT 64 /* heuristic determined experimentally */
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#define MINMATCHLENGTH 7 /* heuristic determined experimentally */
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static dictItem ZDICT_analyzePos(
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BYTE* doneMarks,
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const int* suffix, U32 start,
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const void* buffer, U32 minRatio, U32 notificationLevel)
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{
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U32 lengthList[LLIMIT] = {0};
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U32 cumulLength[LLIMIT] = {0};
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U32 savings[LLIMIT] = {0};
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const BYTE* b = (const BYTE*)buffer;
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size_t maxLength = LLIMIT;
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size_t pos = (size_t)suffix[start];
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U32 end = start;
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dictItem solution;
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/* init */
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memset(&solution, 0, sizeof(solution));
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doneMarks[pos] = 1;
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/* trivial repetition cases */
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if ( (MEM_read16(b+pos+0) == MEM_read16(b+pos+2))
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||(MEM_read16(b+pos+1) == MEM_read16(b+pos+3))
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||(MEM_read16(b+pos+2) == MEM_read16(b+pos+4)) ) {
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/* skip and mark segment */
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U16 const pattern16 = MEM_read16(b+pos+4);
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U32 u, patternEnd = 6;
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while (MEM_read16(b+pos+patternEnd) == pattern16) patternEnd+=2 ;
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if (b[pos+patternEnd] == b[pos+patternEnd-1]) patternEnd++;
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for (u=1; u<patternEnd; u++)
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doneMarks[pos+u] = 1;
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return solution;
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}
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/* look forward */
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{ size_t length;
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do {
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end++;
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length = ZDICT_count(b + pos, b + suffix[end]);
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} while (length >= MINMATCHLENGTH);
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}
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/* look backward */
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{ size_t length;
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do {
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length = ZDICT_count(b + pos, b + *(suffix+start-1));
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if (length >=MINMATCHLENGTH) start--;
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} while(length >= MINMATCHLENGTH);
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}
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/* exit if not found a minimum nb of repetitions */
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if (end-start < minRatio) {
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U32 idx;
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for(idx=start; idx<end; idx++)
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doneMarks[suffix[idx]] = 1;
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return solution;
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}
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{ int i;
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U32 mml;
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U32 refinedStart = start;
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U32 refinedEnd = end;
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DISPLAYLEVEL(4, "\n");
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DISPLAYLEVEL(4, "found %3u matches of length >= %i at pos %7u ", (unsigned)(end-start), MINMATCHLENGTH, (unsigned)pos);
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DISPLAYLEVEL(4, "\n");
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for (mml = MINMATCHLENGTH ; ; mml++) {
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BYTE currentChar = 0;
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U32 currentCount = 0;
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U32 currentID = refinedStart;
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U32 id;
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U32 selectedCount = 0;
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U32 selectedID = currentID;
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for (id =refinedStart; id < refinedEnd; id++) {
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if (b[suffix[id] + mml] != currentChar) {
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if (currentCount > selectedCount) {
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selectedCount = currentCount;
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selectedID = currentID;
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}
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currentID = id;
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currentChar = b[ suffix[id] + mml];
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currentCount = 0;
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}
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currentCount ++;
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}
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if (currentCount > selectedCount) { /* for last */
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selectedCount = currentCount;
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selectedID = currentID;
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}
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if (selectedCount < minRatio)
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break;
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refinedStart = selectedID;
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refinedEnd = refinedStart + selectedCount;
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}
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/* evaluate gain based on new dict */
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start = refinedStart;
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pos = suffix[refinedStart];
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end = start;
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memset(lengthList, 0, sizeof(lengthList));
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/* look forward */
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{ size_t length;
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do {
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end++;
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length = ZDICT_count(b + pos, b + suffix[end]);
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if (length >= LLIMIT) length = LLIMIT-1;
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lengthList[length]++;
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} while (length >=MINMATCHLENGTH);
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}
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/* look backward */
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{ size_t length = MINMATCHLENGTH;
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while ((length >= MINMATCHLENGTH) & (start > 0)) {
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length = ZDICT_count(b + pos, b + suffix[start - 1]);
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if (length >= LLIMIT) length = LLIMIT - 1;
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lengthList[length]++;
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if (length >= MINMATCHLENGTH) start--;
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}
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}
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/* largest useful length */
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memset(cumulLength, 0, sizeof(cumulLength));
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cumulLength[maxLength-1] = lengthList[maxLength-1];
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for (i=(int)(maxLength-2); i>=0; i--)
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cumulLength[i] = cumulLength[i+1] + lengthList[i];
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for (i=LLIMIT-1; i>=MINMATCHLENGTH; i--) if (cumulLength[i]>=minRatio) break;
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maxLength = i;
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/* reduce maxLength in case of final into repetitive data */
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{ U32 l = (U32)maxLength;
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BYTE const c = b[pos + maxLength-1];
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while (b[pos+l-2]==c) l--;
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maxLength = l;
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}
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if (maxLength < MINMATCHLENGTH) return solution; /* skip : no long-enough solution */
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/* calculate savings */
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savings[5] = 0;
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for (i=MINMATCHLENGTH; i<=(int)maxLength; i++)
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savings[i] = savings[i-1] + (lengthList[i] * (i-3));
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DISPLAYLEVEL(4, "Selected dict at position %u, of length %u : saves %u (ratio: %.2f) \n",
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(unsigned)pos, (unsigned)maxLength, (unsigned)savings[maxLength], (double)savings[maxLength] / (double)maxLength);
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solution.pos = (U32)pos;
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solution.length = (U32)maxLength;
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solution.savings = savings[maxLength];
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/* mark positions done */
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{ U32 id;
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for (id=start; id<end; id++) {
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U32 p, pEnd, length;
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U32 const testedPos = (U32)suffix[id];
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if (testedPos == pos)
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length = solution.length;
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else {
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length = (U32)ZDICT_count(b+pos, b+testedPos);
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if (length > solution.length) length = solution.length;
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}
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pEnd = (U32)(testedPos + length);
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for (p=testedPos; p<pEnd; p++)
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doneMarks[p] = 1;
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} } }
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return solution;
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}
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static int isIncluded(const void* in, const void* container, size_t length)
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{
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const char* const ip = (const char*) in;
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const char* const into = (const char*) container;
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size_t u;
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for (u=0; u<length; u++) { /* works because end of buffer is a noisy guard band */
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if (ip[u] != into[u]) break;
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}
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return u==length;
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}
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/*! ZDICT_tryMerge() :
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check if dictItem can be merged, do it if possible
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@return : id of destination elt, 0 if not merged
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*/
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static U32 ZDICT_tryMerge(dictItem* table, dictItem elt, U32 eltNbToSkip, const void* buffer)
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{
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const U32 tableSize = table->pos;
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const U32 eltEnd = elt.pos + elt.length;
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const char* const buf = (const char*) buffer;
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/* tail overlap */
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U32 u; for (u=1; u<tableSize; u++) {
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if (u==eltNbToSkip) continue;
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if ((table[u].pos > elt.pos) && (table[u].pos <= eltEnd)) { /* overlap, existing > new */
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/* append */
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U32 const addedLength = table[u].pos - elt.pos;
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table[u].length += addedLength;
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table[u].pos = elt.pos;
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table[u].savings += elt.savings * addedLength / elt.length; /* rough approx */
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table[u].savings += elt.length / 8; /* rough approx bonus */
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elt = table[u];
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/* sort : improve rank */
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while ((u>1) && (table[u-1].savings < elt.savings))
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table[u] = table[u-1], u--;
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table[u] = elt;
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return u;
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} }
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/* front overlap */
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for (u=1; u<tableSize; u++) {
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if (u==eltNbToSkip) continue;
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if ((table[u].pos + table[u].length >= elt.pos) && (table[u].pos < elt.pos)) { /* overlap, existing < new */
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/* append */
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int const addedLength = (int)eltEnd - (int)(table[u].pos + table[u].length);
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table[u].savings += elt.length / 8; /* rough approx bonus */
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if (addedLength > 0) { /* otherwise, elt fully included into existing */
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table[u].length += addedLength;
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table[u].savings += elt.savings * addedLength / elt.length; /* rough approx */
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}
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/* sort : improve rank */
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elt = table[u];
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while ((u>1) && (table[u-1].savings < elt.savings))
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table[u] = table[u-1], u--;
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table[u] = elt;
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return u;
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}
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if (MEM_read64(buf + table[u].pos) == MEM_read64(buf + elt.pos + 1)) {
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if (isIncluded(buf + table[u].pos, buf + elt.pos + 1, table[u].length)) {
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size_t const addedLength = MAX( (int)elt.length - (int)table[u].length , 1 );
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table[u].pos = elt.pos;
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table[u].savings += (U32)(elt.savings * addedLength / elt.length);
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table[u].length = MIN(elt.length, table[u].length + 1);
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return u;
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}
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}
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}
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return 0;
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}
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static void ZDICT_removeDictItem(dictItem* table, U32 id)
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{
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/* convention : table[0].pos stores nb of elts */
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U32 const max = table[0].pos;
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U32 u;
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if (!id) return; /* protection, should never happen */
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for (u=id; u<max-1; u++)
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table[u] = table[u+1];
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table->pos--;
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}
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static void ZDICT_insertDictItem(dictItem* table, U32 maxSize, dictItem elt, const void* buffer)
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{
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/* merge if possible */
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U32 mergeId = ZDICT_tryMerge(table, elt, 0, buffer);
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if (mergeId) {
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U32 newMerge = 1;
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while (newMerge) {
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newMerge = ZDICT_tryMerge(table, table[mergeId], mergeId, buffer);
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if (newMerge) ZDICT_removeDictItem(table, mergeId);
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mergeId = newMerge;
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}
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return;
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}
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/* insert */
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{ U32 current;
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U32 nextElt = table->pos;
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if (nextElt >= maxSize) nextElt = maxSize-1;
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current = nextElt-1;
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while (table[current].savings < elt.savings) {
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table[current+1] = table[current];
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current--;
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}
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table[current+1] = elt;
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table->pos = nextElt+1;
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}
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}
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static U32 ZDICT_dictSize(const dictItem* dictList)
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{
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U32 u, dictSize = 0;
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for (u=1; u<dictList[0].pos; u++)
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dictSize += dictList[u].length;
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return dictSize;
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}
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static size_t ZDICT_trainBuffer_legacy(dictItem* dictList, U32 dictListSize,
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const void* const buffer, size_t bufferSize, /* buffer must end with noisy guard band */
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const size_t* fileSizes, unsigned nbFiles,
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unsigned minRatio, U32 notificationLevel)
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{
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int* const suffix0 = (int*)malloc((bufferSize+2)*sizeof(*suffix0));
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int* const suffix = suffix0+1;
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U32* reverseSuffix = (U32*)malloc((bufferSize)*sizeof(*reverseSuffix));
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BYTE* doneMarks = (BYTE*)malloc((bufferSize+16)*sizeof(*doneMarks)); /* +16 for overflow security */
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U32* filePos = (U32*)malloc(nbFiles * sizeof(*filePos));
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size_t result = 0;
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clock_t displayClock = 0;
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clock_t const refreshRate = CLOCKS_PER_SEC * 3 / 10;
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# undef DISPLAYUPDATE
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# define DISPLAYUPDATE(l, ...) if (notificationLevel>=l) { \
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if (ZDICT_clockSpan(displayClock) > refreshRate) \
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{ displayClock = clock(); DISPLAY(__VA_ARGS__); \
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if (notificationLevel>=4) fflush(stderr); } }
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/* init */
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DISPLAYLEVEL(2, "\r%70s\r", ""); /* clean display line */
|
|
if (!suffix0 || !reverseSuffix || !doneMarks || !filePos) {
|
|
result = ERROR(memory_allocation);
|
|
goto _cleanup;
|
|
}
|
|
if (minRatio < MINRATIO) minRatio = MINRATIO;
|
|
memset(doneMarks, 0, bufferSize+16);
|
|
|
|
/* limit sample set size (divsufsort limitation)*/
|
|
if (bufferSize > ZDICT_MAX_SAMPLES_SIZE) DISPLAYLEVEL(3, "sample set too large : reduced to %u MB ...\n", (unsigned)(ZDICT_MAX_SAMPLES_SIZE>>20));
|
|
while (bufferSize > ZDICT_MAX_SAMPLES_SIZE) bufferSize -= fileSizes[--nbFiles];
|
|
|
|
/* sort */
|
|
DISPLAYLEVEL(2, "sorting %u files of total size %u MB ...\n", nbFiles, (unsigned)(bufferSize>>20));
|
|
{ int const divSuftSortResult = divsufsort((const unsigned char*)buffer, suffix, (int)bufferSize, 0);
|
|
if (divSuftSortResult != 0) { result = ERROR(GENERIC); goto _cleanup; }
|
|
}
|
|
suffix[bufferSize] = (int)bufferSize; /* leads into noise */
|
|
suffix0[0] = (int)bufferSize; /* leads into noise */
|
|
/* build reverse suffix sort */
|
|
{ size_t pos;
|
|
for (pos=0; pos < bufferSize; pos++)
|
|
reverseSuffix[suffix[pos]] = (U32)pos;
|
|
/* note filePos tracks borders between samples.
|
|
It's not used at this stage, but planned to become useful in a later update */
|
|
filePos[0] = 0;
|
|
for (pos=1; pos<nbFiles; pos++)
|
|
filePos[pos] = (U32)(filePos[pos-1] + fileSizes[pos-1]);
|
|
}
|
|
|
|
DISPLAYLEVEL(2, "finding patterns ... \n");
|
|
DISPLAYLEVEL(3, "minimum ratio : %u \n", minRatio);
|
|
|
|
{ U32 cursor; for (cursor=0; cursor < bufferSize; ) {
|
|
dictItem solution;
|
|
if (doneMarks[cursor]) { cursor++; continue; }
|
|
solution = ZDICT_analyzePos(doneMarks, suffix, reverseSuffix[cursor], buffer, minRatio, notificationLevel);
|
|
if (solution.length==0) { cursor++; continue; }
|
|
ZDICT_insertDictItem(dictList, dictListSize, solution, buffer);
|
|
cursor += solution.length;
|
|
DISPLAYUPDATE(2, "\r%4.2f %% \r", (double)cursor / (double)bufferSize * 100.0);
|
|
} }
|
|
|
|
_cleanup:
|
|
free(suffix0);
|
|
free(reverseSuffix);
|
|
free(doneMarks);
|
|
free(filePos);
|
|
return result;
|
|
}
|
|
|
|
|
|
static void ZDICT_fillNoise(void* buffer, size_t length)
|
|
{
|
|
unsigned const prime1 = 2654435761U;
|
|
unsigned const prime2 = 2246822519U;
|
|
unsigned acc = prime1;
|
|
size_t p=0;
|
|
for (p=0; p<length; p++) {
|
|
acc *= prime2;
|
|
((unsigned char*)buffer)[p] = (unsigned char)(acc >> 21);
|
|
}
|
|
}
|
|
|
|
|
|
typedef struct
|
|
{
|
|
ZSTD_CDict* dict; /* dictionary */
|
|
ZSTD_CCtx* zc; /* working context */
|
|
void* workPlace; /* must be ZSTD_BLOCKSIZE_MAX allocated */
|
|
} EStats_ress_t;
|
|
|
|
#define MAXREPOFFSET 1024
|
|
|
|
static void ZDICT_countEStats(EStats_ress_t esr, const ZSTD_parameters* params,
|
|
unsigned* countLit, unsigned* offsetcodeCount, unsigned* matchlengthCount, unsigned* litlengthCount, U32* repOffsets,
|
|
const void* src, size_t srcSize,
|
|
U32 notificationLevel)
|
|
{
|
|
size_t const blockSizeMax = MIN (ZSTD_BLOCKSIZE_MAX, 1 << params->cParams.windowLog);
|
|
size_t cSize;
|
|
|
|
if (srcSize > blockSizeMax) srcSize = blockSizeMax; /* protection vs large samples */
|
|
{ size_t const errorCode = ZSTD_compressBegin_usingCDict_deprecated(esr.zc, esr.dict);
|
|
if (ZSTD_isError(errorCode)) { DISPLAYLEVEL(1, "warning : ZSTD_compressBegin_usingCDict failed \n"); return; }
|
|
|
|
}
|
|
cSize = ZSTD_compressBlock_deprecated(esr.zc, esr.workPlace, ZSTD_BLOCKSIZE_MAX, src, srcSize);
|
|
if (ZSTD_isError(cSize)) { DISPLAYLEVEL(3, "warning : could not compress sample size %u \n", (unsigned)srcSize); return; }
|
|
|
|
if (cSize) { /* if == 0; block is not compressible */
|
|
const seqStore_t* const seqStorePtr = ZSTD_getSeqStore(esr.zc);
|
|
|
|
/* literals stats */
|
|
{ const BYTE* bytePtr;
|
|
for(bytePtr = seqStorePtr->litStart; bytePtr < seqStorePtr->lit; bytePtr++)
|
|
countLit[*bytePtr]++;
|
|
}
|
|
|
|
/* seqStats */
|
|
{ U32 const nbSeq = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
|
|
ZSTD_seqToCodes(seqStorePtr);
|
|
|
|
{ const BYTE* codePtr = seqStorePtr->ofCode;
|
|
U32 u;
|
|
for (u=0; u<nbSeq; u++) offsetcodeCount[codePtr[u]]++;
|
|
}
|
|
|
|
{ const BYTE* codePtr = seqStorePtr->mlCode;
|
|
U32 u;
|
|
for (u=0; u<nbSeq; u++) matchlengthCount[codePtr[u]]++;
|
|
}
|
|
|
|
{ const BYTE* codePtr = seqStorePtr->llCode;
|
|
U32 u;
|
|
for (u=0; u<nbSeq; u++) litlengthCount[codePtr[u]]++;
|
|
}
|
|
|
|
if (nbSeq >= 2) { /* rep offsets */
|
|
const seqDef* const seq = seqStorePtr->sequencesStart;
|
|
U32 offset1 = seq[0].offBase - ZSTD_REP_NUM;
|
|
U32 offset2 = seq[1].offBase - ZSTD_REP_NUM;
|
|
if (offset1 >= MAXREPOFFSET) offset1 = 0;
|
|
if (offset2 >= MAXREPOFFSET) offset2 = 0;
|
|
repOffsets[offset1] += 3;
|
|
repOffsets[offset2] += 1;
|
|
} } }
|
|
}
|
|
|
|
static size_t ZDICT_totalSampleSize(const size_t* fileSizes, unsigned nbFiles)
|
|
{
|
|
size_t total=0;
|
|
unsigned u;
|
|
for (u=0; u<nbFiles; u++) total += fileSizes[u];
|
|
return total;
|
|
}
|
|
|
|
typedef struct { U32 offset; U32 count; } offsetCount_t;
|
|
|
|
static void ZDICT_insertSortCount(offsetCount_t table[ZSTD_REP_NUM+1], U32 val, U32 count)
|
|
{
|
|
U32 u;
|
|
table[ZSTD_REP_NUM].offset = val;
|
|
table[ZSTD_REP_NUM].count = count;
|
|
for (u=ZSTD_REP_NUM; u>0; u--) {
|
|
offsetCount_t tmp;
|
|
if (table[u-1].count >= table[u].count) break;
|
|
tmp = table[u-1];
|
|
table[u-1] = table[u];
|
|
table[u] = tmp;
|
|
}
|
|
}
|
|
|
|
/* ZDICT_flatLit() :
|
|
* rewrite `countLit` to contain a mostly flat but still compressible distribution of literals.
|
|
* necessary to avoid generating a non-compressible distribution that HUF_writeCTable() cannot encode.
|
|
*/
|
|
static void ZDICT_flatLit(unsigned* countLit)
|
|
{
|
|
int u;
|
|
for (u=1; u<256; u++) countLit[u] = 2;
|
|
countLit[0] = 4;
|
|
countLit[253] = 1;
|
|
countLit[254] = 1;
|
|
}
|
|
|
|
#define OFFCODE_MAX 30 /* only applicable to first block */
|
|
static size_t ZDICT_analyzeEntropy(void* dstBuffer, size_t maxDstSize,
|
|
int compressionLevel,
|
|
const void* srcBuffer, const size_t* fileSizes, unsigned nbFiles,
|
|
const void* dictBuffer, size_t dictBufferSize,
|
|
unsigned notificationLevel)
|
|
{
|
|
unsigned countLit[256];
|
|
HUF_CREATE_STATIC_CTABLE(hufTable, 255);
|
|
unsigned offcodeCount[OFFCODE_MAX+1];
|
|
short offcodeNCount[OFFCODE_MAX+1];
|
|
U32 offcodeMax = ZSTD_highbit32((U32)(dictBufferSize + 128 KB));
|
|
unsigned matchLengthCount[MaxML+1];
|
|
short matchLengthNCount[MaxML+1];
|
|
unsigned litLengthCount[MaxLL+1];
|
|
short litLengthNCount[MaxLL+1];
|
|
U32 repOffset[MAXREPOFFSET];
|
|
offsetCount_t bestRepOffset[ZSTD_REP_NUM+1];
|
|
EStats_ress_t esr = { NULL, NULL, NULL };
|
|
ZSTD_parameters params;
|
|
U32 u, huffLog = 11, Offlog = OffFSELog, mlLog = MLFSELog, llLog = LLFSELog, total;
|
|
size_t pos = 0, errorCode;
|
|
size_t eSize = 0;
|
|
size_t const totalSrcSize = ZDICT_totalSampleSize(fileSizes, nbFiles);
|
|
size_t const averageSampleSize = totalSrcSize / (nbFiles + !nbFiles);
|
|
BYTE* dstPtr = (BYTE*)dstBuffer;
|
|
U32 wksp[HUF_CTABLE_WORKSPACE_SIZE_U32];
|
|
|
|
/* init */
|
|
DEBUGLOG(4, "ZDICT_analyzeEntropy");
|
|
if (offcodeMax>OFFCODE_MAX) { eSize = ERROR(dictionaryCreation_failed); goto _cleanup; } /* too large dictionary */
|
|
for (u=0; u<256; u++) countLit[u] = 1; /* any character must be described */
|
|
for (u=0; u<=offcodeMax; u++) offcodeCount[u] = 1;
|
|
for (u=0; u<=MaxML; u++) matchLengthCount[u] = 1;
|
|
for (u=0; u<=MaxLL; u++) litLengthCount[u] = 1;
|
|
memset(repOffset, 0, sizeof(repOffset));
|
|
repOffset[1] = repOffset[4] = repOffset[8] = 1;
|
|
memset(bestRepOffset, 0, sizeof(bestRepOffset));
|
|
if (compressionLevel==0) compressionLevel = ZSTD_CLEVEL_DEFAULT;
|
|
params = ZSTD_getParams(compressionLevel, averageSampleSize, dictBufferSize);
|
|
|
|
esr.dict = ZSTD_createCDict_advanced(dictBuffer, dictBufferSize, ZSTD_dlm_byRef, ZSTD_dct_rawContent, params.cParams, ZSTD_defaultCMem);
|
|
esr.zc = ZSTD_createCCtx();
|
|
esr.workPlace = malloc(ZSTD_BLOCKSIZE_MAX);
|
|
if (!esr.dict || !esr.zc || !esr.workPlace) {
|
|
eSize = ERROR(memory_allocation);
|
|
DISPLAYLEVEL(1, "Not enough memory \n");
|
|
goto _cleanup;
|
|
}
|
|
|
|
/* collect stats on all samples */
|
|
for (u=0; u<nbFiles; u++) {
|
|
ZDICT_countEStats(esr, ¶ms,
|
|
countLit, offcodeCount, matchLengthCount, litLengthCount, repOffset,
|
|
(const char*)srcBuffer + pos, fileSizes[u],
|
|
notificationLevel);
|
|
pos += fileSizes[u];
|
|
}
|
|
|
|
if (notificationLevel >= 4) {
|
|
/* writeStats */
|
|
DISPLAYLEVEL(4, "Offset Code Frequencies : \n");
|
|
for (u=0; u<=offcodeMax; u++) {
|
|
DISPLAYLEVEL(4, "%2u :%7u \n", u, offcodeCount[u]);
|
|
} }
|
|
|
|
/* analyze, build stats, starting with literals */
|
|
{ size_t maxNbBits = HUF_buildCTable_wksp(hufTable, countLit, 255, huffLog, wksp, sizeof(wksp));
|
|
if (HUF_isError(maxNbBits)) {
|
|
eSize = maxNbBits;
|
|
DISPLAYLEVEL(1, " HUF_buildCTable error \n");
|
|
goto _cleanup;
|
|
}
|
|
if (maxNbBits==8) { /* not compressible : will fail on HUF_writeCTable() */
|
|
DISPLAYLEVEL(2, "warning : pathological dataset : literals are not compressible : samples are noisy or too regular \n");
|
|
ZDICT_flatLit(countLit); /* replace distribution by a fake "mostly flat but still compressible" distribution, that HUF_writeCTable() can encode */
|
|
maxNbBits = HUF_buildCTable_wksp(hufTable, countLit, 255, huffLog, wksp, sizeof(wksp));
|
|
assert(maxNbBits==9);
|
|
}
|
|
huffLog = (U32)maxNbBits;
|
|
}
|
|
|
|
/* looking for most common first offsets */
|
|
{ U32 offset;
|
|
for (offset=1; offset<MAXREPOFFSET; offset++)
|
|
ZDICT_insertSortCount(bestRepOffset, offset, repOffset[offset]);
|
|
}
|
|
/* note : the result of this phase should be used to better appreciate the impact on statistics */
|
|
|
|
total=0; for (u=0; u<=offcodeMax; u++) total+=offcodeCount[u];
|
|
errorCode = FSE_normalizeCount(offcodeNCount, Offlog, offcodeCount, total, offcodeMax, /* useLowProbCount */ 1);
|
|
if (FSE_isError(errorCode)) {
|
|
eSize = errorCode;
|
|
DISPLAYLEVEL(1, "FSE_normalizeCount error with offcodeCount \n");
|
|
goto _cleanup;
|
|
}
|
|
Offlog = (U32)errorCode;
|
|
|
|
total=0; for (u=0; u<=MaxML; u++) total+=matchLengthCount[u];
|
|
errorCode = FSE_normalizeCount(matchLengthNCount, mlLog, matchLengthCount, total, MaxML, /* useLowProbCount */ 1);
|
|
if (FSE_isError(errorCode)) {
|
|
eSize = errorCode;
|
|
DISPLAYLEVEL(1, "FSE_normalizeCount error with matchLengthCount \n");
|
|
goto _cleanup;
|
|
}
|
|
mlLog = (U32)errorCode;
|
|
|
|
total=0; for (u=0; u<=MaxLL; u++) total+=litLengthCount[u];
|
|
errorCode = FSE_normalizeCount(litLengthNCount, llLog, litLengthCount, total, MaxLL, /* useLowProbCount */ 1);
|
|
if (FSE_isError(errorCode)) {
|
|
eSize = errorCode;
|
|
DISPLAYLEVEL(1, "FSE_normalizeCount error with litLengthCount \n");
|
|
goto _cleanup;
|
|
}
|
|
llLog = (U32)errorCode;
|
|
|
|
/* write result to buffer */
|
|
{ size_t const hhSize = HUF_writeCTable_wksp(dstPtr, maxDstSize, hufTable, 255, huffLog, wksp, sizeof(wksp));
|
|
if (HUF_isError(hhSize)) {
|
|
eSize = hhSize;
|
|
DISPLAYLEVEL(1, "HUF_writeCTable error \n");
|
|
goto _cleanup;
|
|
}
|
|
dstPtr += hhSize;
|
|
maxDstSize -= hhSize;
|
|
eSize += hhSize;
|
|
}
|
|
|
|
{ size_t const ohSize = FSE_writeNCount(dstPtr, maxDstSize, offcodeNCount, OFFCODE_MAX, Offlog);
|
|
if (FSE_isError(ohSize)) {
|
|
eSize = ohSize;
|
|
DISPLAYLEVEL(1, "FSE_writeNCount error with offcodeNCount \n");
|
|
goto _cleanup;
|
|
}
|
|
dstPtr += ohSize;
|
|
maxDstSize -= ohSize;
|
|
eSize += ohSize;
|
|
}
|
|
|
|
{ size_t const mhSize = FSE_writeNCount(dstPtr, maxDstSize, matchLengthNCount, MaxML, mlLog);
|
|
if (FSE_isError(mhSize)) {
|
|
eSize = mhSize;
|
|
DISPLAYLEVEL(1, "FSE_writeNCount error with matchLengthNCount \n");
|
|
goto _cleanup;
|
|
}
|
|
dstPtr += mhSize;
|
|
maxDstSize -= mhSize;
|
|
eSize += mhSize;
|
|
}
|
|
|
|
{ size_t const lhSize = FSE_writeNCount(dstPtr, maxDstSize, litLengthNCount, MaxLL, llLog);
|
|
if (FSE_isError(lhSize)) {
|
|
eSize = lhSize;
|
|
DISPLAYLEVEL(1, "FSE_writeNCount error with litlengthNCount \n");
|
|
goto _cleanup;
|
|
}
|
|
dstPtr += lhSize;
|
|
maxDstSize -= lhSize;
|
|
eSize += lhSize;
|
|
}
|
|
|
|
if (maxDstSize<12) {
|
|
eSize = ERROR(dstSize_tooSmall);
|
|
DISPLAYLEVEL(1, "not enough space to write RepOffsets \n");
|
|
goto _cleanup;
|
|
}
|
|
# if 0
|
|
MEM_writeLE32(dstPtr+0, bestRepOffset[0].offset);
|
|
MEM_writeLE32(dstPtr+4, bestRepOffset[1].offset);
|
|
MEM_writeLE32(dstPtr+8, bestRepOffset[2].offset);
|
|
#else
|
|
/* at this stage, we don't use the result of "most common first offset",
|
|
* as the impact of statistics is not properly evaluated */
|
|
MEM_writeLE32(dstPtr+0, repStartValue[0]);
|
|
MEM_writeLE32(dstPtr+4, repStartValue[1]);
|
|
MEM_writeLE32(dstPtr+8, repStartValue[2]);
|
|
#endif
|
|
eSize += 12;
|
|
|
|
_cleanup:
|
|
ZSTD_freeCDict(esr.dict);
|
|
ZSTD_freeCCtx(esr.zc);
|
|
free(esr.workPlace);
|
|
|
|
return eSize;
|
|
}
|
|
|
|
|
|
/**
|
|
* @returns the maximum repcode value
|
|
*/
|
|
static U32 ZDICT_maxRep(U32 const reps[ZSTD_REP_NUM])
|
|
{
|
|
U32 maxRep = reps[0];
|
|
int r;
|
|
for (r = 1; r < ZSTD_REP_NUM; ++r)
|
|
maxRep = MAX(maxRep, reps[r]);
|
|
return maxRep;
|
|
}
|
|
|
|
size_t ZDICT_finalizeDictionary(void* dictBuffer, size_t dictBufferCapacity,
|
|
const void* customDictContent, size_t dictContentSize,
|
|
const void* samplesBuffer, const size_t* samplesSizes,
|
|
unsigned nbSamples, ZDICT_params_t params)
|
|
{
|
|
size_t hSize;
|
|
#define HBUFFSIZE 256 /* should prove large enough for all entropy headers */
|
|
BYTE header[HBUFFSIZE];
|
|
int const compressionLevel = (params.compressionLevel == 0) ? ZSTD_CLEVEL_DEFAULT : params.compressionLevel;
|
|
U32 const notificationLevel = params.notificationLevel;
|
|
/* The final dictionary content must be at least as large as the largest repcode */
|
|
size_t const minContentSize = (size_t)ZDICT_maxRep(repStartValue);
|
|
size_t paddingSize;
|
|
|
|
/* check conditions */
|
|
DEBUGLOG(4, "ZDICT_finalizeDictionary");
|
|
if (dictBufferCapacity < dictContentSize) return ERROR(dstSize_tooSmall);
|
|
if (dictBufferCapacity < ZDICT_DICTSIZE_MIN) return ERROR(dstSize_tooSmall);
|
|
|
|
/* dictionary header */
|
|
MEM_writeLE32(header, ZSTD_MAGIC_DICTIONARY);
|
|
{ U64 const randomID = XXH64(customDictContent, dictContentSize, 0);
|
|
U32 const compliantID = (randomID % ((1U<<31)-32768)) + 32768;
|
|
U32 const dictID = params.dictID ? params.dictID : compliantID;
|
|
MEM_writeLE32(header+4, dictID);
|
|
}
|
|
hSize = 8;
|
|
|
|
/* entropy tables */
|
|
DISPLAYLEVEL(2, "\r%70s\r", ""); /* clean display line */
|
|
DISPLAYLEVEL(2, "statistics ... \n");
|
|
{ size_t const eSize = ZDICT_analyzeEntropy(header+hSize, HBUFFSIZE-hSize,
|
|
compressionLevel,
|
|
samplesBuffer, samplesSizes, nbSamples,
|
|
customDictContent, dictContentSize,
|
|
notificationLevel);
|
|
if (ZDICT_isError(eSize)) return eSize;
|
|
hSize += eSize;
|
|
}
|
|
|
|
/* Shrink the content size if it doesn't fit in the buffer */
|
|
if (hSize + dictContentSize > dictBufferCapacity) {
|
|
dictContentSize = dictBufferCapacity - hSize;
|
|
}
|
|
|
|
/* Pad the dictionary content with zeros if it is too small */
|
|
if (dictContentSize < minContentSize) {
|
|
RETURN_ERROR_IF(hSize + minContentSize > dictBufferCapacity, dstSize_tooSmall,
|
|
"dictBufferCapacity too small to fit max repcode");
|
|
paddingSize = minContentSize - dictContentSize;
|
|
} else {
|
|
paddingSize = 0;
|
|
}
|
|
|
|
{
|
|
size_t const dictSize = hSize + paddingSize + dictContentSize;
|
|
|
|
/* The dictionary consists of the header, optional padding, and the content.
|
|
* The padding comes before the content because the "best" position in the
|
|
* dictionary is the last byte.
|
|
*/
|
|
BYTE* const outDictHeader = (BYTE*)dictBuffer;
|
|
BYTE* const outDictPadding = outDictHeader + hSize;
|
|
BYTE* const outDictContent = outDictPadding + paddingSize;
|
|
|
|
assert(dictSize <= dictBufferCapacity);
|
|
assert(outDictContent + dictContentSize == (BYTE*)dictBuffer + dictSize);
|
|
|
|
/* First copy the customDictContent into its final location.
|
|
* `customDictContent` and `dictBuffer` may overlap, so we must
|
|
* do this before any other writes into the output buffer.
|
|
* Then copy the header & padding into the output buffer.
|
|
*/
|
|
memmove(outDictContent, customDictContent, dictContentSize);
|
|
memcpy(outDictHeader, header, hSize);
|
|
memset(outDictPadding, 0, paddingSize);
|
|
|
|
return dictSize;
|
|
}
|
|
}
|
|
|
|
|
|
static size_t ZDICT_addEntropyTablesFromBuffer_advanced(
|
|
void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
|
|
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
|
|
ZDICT_params_t params)
|
|
{
|
|
int const compressionLevel = (params.compressionLevel == 0) ? ZSTD_CLEVEL_DEFAULT : params.compressionLevel;
|
|
U32 const notificationLevel = params.notificationLevel;
|
|
size_t hSize = 8;
|
|
|
|
/* calculate entropy tables */
|
|
DISPLAYLEVEL(2, "\r%70s\r", ""); /* clean display line */
|
|
DISPLAYLEVEL(2, "statistics ... \n");
|
|
{ size_t const eSize = ZDICT_analyzeEntropy((char*)dictBuffer+hSize, dictBufferCapacity-hSize,
|
|
compressionLevel,
|
|
samplesBuffer, samplesSizes, nbSamples,
|
|
(char*)dictBuffer + dictBufferCapacity - dictContentSize, dictContentSize,
|
|
notificationLevel);
|
|
if (ZDICT_isError(eSize)) return eSize;
|
|
hSize += eSize;
|
|
}
|
|
|
|
/* add dictionary header (after entropy tables) */
|
|
MEM_writeLE32(dictBuffer, ZSTD_MAGIC_DICTIONARY);
|
|
{ U64 const randomID = XXH64((char*)dictBuffer + dictBufferCapacity - dictContentSize, dictContentSize, 0);
|
|
U32 const compliantID = (randomID % ((1U<<31)-32768)) + 32768;
|
|
U32 const dictID = params.dictID ? params.dictID : compliantID;
|
|
MEM_writeLE32((char*)dictBuffer+4, dictID);
|
|
}
|
|
|
|
if (hSize + dictContentSize < dictBufferCapacity)
|
|
memmove((char*)dictBuffer + hSize, (char*)dictBuffer + dictBufferCapacity - dictContentSize, dictContentSize);
|
|
return MIN(dictBufferCapacity, hSize+dictContentSize);
|
|
}
|
|
|
|
/*! ZDICT_trainFromBuffer_unsafe_legacy() :
|
|
* Warning : `samplesBuffer` must be followed by noisy guard band !!!
|
|
* @return : size of dictionary, or an error code which can be tested with ZDICT_isError()
|
|
*/
|
|
static size_t ZDICT_trainFromBuffer_unsafe_legacy(
|
|
void* dictBuffer, size_t maxDictSize,
|
|
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
|
|
ZDICT_legacy_params_t params)
|
|
{
|
|
U32 const dictListSize = MAX(MAX(DICTLISTSIZE_DEFAULT, nbSamples), (U32)(maxDictSize/16));
|
|
dictItem* const dictList = (dictItem*)malloc(dictListSize * sizeof(*dictList));
|
|
unsigned const selectivity = params.selectivityLevel == 0 ? g_selectivity_default : params.selectivityLevel;
|
|
unsigned const minRep = (selectivity > 30) ? MINRATIO : nbSamples >> selectivity;
|
|
size_t const targetDictSize = maxDictSize;
|
|
size_t const samplesBuffSize = ZDICT_totalSampleSize(samplesSizes, nbSamples);
|
|
size_t dictSize = 0;
|
|
U32 const notificationLevel = params.zParams.notificationLevel;
|
|
|
|
/* checks */
|
|
if (!dictList) return ERROR(memory_allocation);
|
|
if (maxDictSize < ZDICT_DICTSIZE_MIN) { free(dictList); return ERROR(dstSize_tooSmall); } /* requested dictionary size is too small */
|
|
if (samplesBuffSize < ZDICT_MIN_SAMPLES_SIZE) { free(dictList); return ERROR(dictionaryCreation_failed); } /* not enough source to create dictionary */
|
|
|
|
/* init */
|
|
ZDICT_initDictItem(dictList);
|
|
|
|
/* build dictionary */
|
|
ZDICT_trainBuffer_legacy(dictList, dictListSize,
|
|
samplesBuffer, samplesBuffSize,
|
|
samplesSizes, nbSamples,
|
|
minRep, notificationLevel);
|
|
|
|
/* display best matches */
|
|
if (params.zParams.notificationLevel>= 3) {
|
|
unsigned const nb = MIN(25, dictList[0].pos);
|
|
unsigned const dictContentSize = ZDICT_dictSize(dictList);
|
|
unsigned u;
|
|
DISPLAYLEVEL(3, "\n %u segments found, of total size %u \n", (unsigned)dictList[0].pos-1, dictContentSize);
|
|
DISPLAYLEVEL(3, "list %u best segments \n", nb-1);
|
|
for (u=1; u<nb; u++) {
|
|
unsigned const pos = dictList[u].pos;
|
|
unsigned const length = dictList[u].length;
|
|
U32 const printedLength = MIN(40, length);
|
|
if ((pos > samplesBuffSize) || ((pos + length) > samplesBuffSize)) {
|
|
free(dictList);
|
|
return ERROR(GENERIC); /* should never happen */
|
|
}
|
|
DISPLAYLEVEL(3, "%3u:%3u bytes at pos %8u, savings %7u bytes |",
|
|
u, length, pos, (unsigned)dictList[u].savings);
|
|
ZDICT_printHex((const char*)samplesBuffer+pos, printedLength);
|
|
DISPLAYLEVEL(3, "| \n");
|
|
} }
|
|
|
|
|
|
/* create dictionary */
|
|
{ unsigned dictContentSize = ZDICT_dictSize(dictList);
|
|
if (dictContentSize < ZDICT_CONTENTSIZE_MIN) { free(dictList); return ERROR(dictionaryCreation_failed); } /* dictionary content too small */
|
|
if (dictContentSize < targetDictSize/4) {
|
|
DISPLAYLEVEL(2, "! warning : selected content significantly smaller than requested (%u < %u) \n", dictContentSize, (unsigned)maxDictSize);
|
|
if (samplesBuffSize < 10 * targetDictSize)
|
|
DISPLAYLEVEL(2, "! consider increasing the number of samples (total size : %u MB)\n", (unsigned)(samplesBuffSize>>20));
|
|
if (minRep > MINRATIO) {
|
|
DISPLAYLEVEL(2, "! consider increasing selectivity to produce larger dictionary (-s%u) \n", selectivity+1);
|
|
DISPLAYLEVEL(2, "! note : larger dictionaries are not necessarily better, test its efficiency on samples \n");
|
|
}
|
|
}
|
|
|
|
if ((dictContentSize > targetDictSize*3) && (nbSamples > 2*MINRATIO) && (selectivity>1)) {
|
|
unsigned proposedSelectivity = selectivity-1;
|
|
while ((nbSamples >> proposedSelectivity) <= MINRATIO) { proposedSelectivity--; }
|
|
DISPLAYLEVEL(2, "! note : calculated dictionary significantly larger than requested (%u > %u) \n", dictContentSize, (unsigned)maxDictSize);
|
|
DISPLAYLEVEL(2, "! consider increasing dictionary size, or produce denser dictionary (-s%u) \n", proposedSelectivity);
|
|
DISPLAYLEVEL(2, "! always test dictionary efficiency on real samples \n");
|
|
}
|
|
|
|
/* limit dictionary size */
|
|
{ U32 const max = dictList->pos; /* convention : nb of useful elts within dictList */
|
|
U32 currentSize = 0;
|
|
U32 n; for (n=1; n<max; n++) {
|
|
currentSize += dictList[n].length;
|
|
if (currentSize > targetDictSize) { currentSize -= dictList[n].length; break; }
|
|
}
|
|
dictList->pos = n;
|
|
dictContentSize = currentSize;
|
|
}
|
|
|
|
/* build dict content */
|
|
{ U32 u;
|
|
BYTE* ptr = (BYTE*)dictBuffer + maxDictSize;
|
|
for (u=1; u<dictList->pos; u++) {
|
|
U32 l = dictList[u].length;
|
|
ptr -= l;
|
|
if (ptr<(BYTE*)dictBuffer) { free(dictList); return ERROR(GENERIC); } /* should not happen */
|
|
memcpy(ptr, (const char*)samplesBuffer+dictList[u].pos, l);
|
|
} }
|
|
|
|
dictSize = ZDICT_addEntropyTablesFromBuffer_advanced(dictBuffer, dictContentSize, maxDictSize,
|
|
samplesBuffer, samplesSizes, nbSamples,
|
|
params.zParams);
|
|
}
|
|
|
|
/* clean up */
|
|
free(dictList);
|
|
return dictSize;
|
|
}
|
|
|
|
|
|
/* ZDICT_trainFromBuffer_legacy() :
|
|
* issue : samplesBuffer need to be followed by a noisy guard band.
|
|
* work around : duplicate the buffer, and add the noise */
|
|
size_t ZDICT_trainFromBuffer_legacy(void* dictBuffer, size_t dictBufferCapacity,
|
|
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
|
|
ZDICT_legacy_params_t params)
|
|
{
|
|
size_t result;
|
|
void* newBuff;
|
|
size_t const sBuffSize = ZDICT_totalSampleSize(samplesSizes, nbSamples);
|
|
if (sBuffSize < ZDICT_MIN_SAMPLES_SIZE) return 0; /* not enough content => no dictionary */
|
|
|
|
newBuff = malloc(sBuffSize + NOISELENGTH);
|
|
if (!newBuff) return ERROR(memory_allocation);
|
|
|
|
memcpy(newBuff, samplesBuffer, sBuffSize);
|
|
ZDICT_fillNoise((char*)newBuff + sBuffSize, NOISELENGTH); /* guard band, for end of buffer condition */
|
|
|
|
result =
|
|
ZDICT_trainFromBuffer_unsafe_legacy(dictBuffer, dictBufferCapacity, newBuff,
|
|
samplesSizes, nbSamples, params);
|
|
free(newBuff);
|
|
return result;
|
|
}
|
|
|
|
|
|
size_t ZDICT_trainFromBuffer(void* dictBuffer, size_t dictBufferCapacity,
|
|
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples)
|
|
{
|
|
ZDICT_fastCover_params_t params;
|
|
DEBUGLOG(3, "ZDICT_trainFromBuffer");
|
|
memset(¶ms, 0, sizeof(params));
|
|
params.d = 8;
|
|
params.steps = 4;
|
|
/* Use default level since no compression level information is available */
|
|
params.zParams.compressionLevel = ZSTD_CLEVEL_DEFAULT;
|
|
#if defined(DEBUGLEVEL) && (DEBUGLEVEL>=1)
|
|
params.zParams.notificationLevel = DEBUGLEVEL;
|
|
#endif
|
|
return ZDICT_optimizeTrainFromBuffer_fastCover(dictBuffer, dictBufferCapacity,
|
|
samplesBuffer, samplesSizes, nbSamples,
|
|
¶ms);
|
|
}
|
|
|
|
size_t ZDICT_addEntropyTablesFromBuffer(void* dictBuffer, size_t dictContentSize, size_t dictBufferCapacity,
|
|
const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples)
|
|
{
|
|
ZDICT_params_t params;
|
|
memset(¶ms, 0, sizeof(params));
|
|
return ZDICT_addEntropyTablesFromBuffer_advanced(dictBuffer, dictContentSize, dictBufferCapacity,
|
|
samplesBuffer, samplesSizes, nbSamples,
|
|
params);
|
|
}
|