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			1036 lines
		
	
	
		
			38 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1036 lines
		
	
	
		
			38 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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    dictBuilder - dictionary builder for zstd
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    Copyright (C) Yann Collet 2016
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    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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    Redistribution and use in source and binary forms, with or without
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    modification, are permitted provided that the following conditions are
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    met:
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    * Redistributions of source code must retain the above copyright
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    notice, this list of conditions and the following disclaimer.
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    * Redistributions in binary form must reproduce the above
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    copyright notice, this list of conditions and the following disclaimer
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    in the documentation and/or other materials provided with the
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    distribution.
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    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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    You can contact the author at :
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    - Zstd homepage : https://www.zstd.net
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*/
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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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#  define _LARGEFILE_SOURCE
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#elif ! defined(__LP64__)                        /* No point defining Large file for 64 bit */
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#  define _LARGEFILE64_SOURCE
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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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#include "mem.h"           /* read */
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#include "error_private.h"
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#include "fse.h"           /* FSE_normalizeCount, FSE_writeNCount */
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#define HUF_STATIC_LINKING_ONLY
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#include "huf.h"
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#include "zstd_internal.h" /* includes zstd.h */
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#include "xxhash.h"
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#include "divsufsort.h"
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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 "zdict.h"
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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 10000
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#define NOISELENGTH 32
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#define PRIME1   2654435761U
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#define PRIME2   2246822519U
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#define MINRATIO 4
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static const U32 g_compressionLevel_default = 5;
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static const U32 g_selectivity_default = 9;
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static const size_t g_provision_entropySize = 200;
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static const size_t g_min_fast_dictContent = 192;
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/*-*************************************
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*  Console display
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***************************************/
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#define DISPLAY(...)         { fprintf(stderr, __VA_ARGS__); fflush( stderr ); }
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#define DISPLAYLEVEL(l, ...) if (g_displayLevel>=l) { DISPLAY(__VA_ARGS__); }
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static unsigned g_displayLevel = 0;   /* 0 : no display;   1: errors;   2: default;  4: full information */
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#define DISPLAYUPDATE(l, ...) if (g_displayLevel>=l) { \
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            if (ZDICT_clockSpan(g_time) > refreshRate)  \
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            { g_time = clock(); DISPLAY(__VA_ARGS__); \
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            if (g_displayLevel>=4) fflush(stdout); } }
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static const unsigned refreshRate = CLOCKS_PER_SEC * 3 / 10;
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static clock_t g_time = 0;
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static clock_t ZDICT_clockSpan(clock_t nPrevious) { return clock() - nPrevious; }
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static void ZDICT_printHex(U32 dlevel, 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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        DISPLAYLEVEL(dlevel, "%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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/*-********************************************************
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*  Dictionary training functions
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**********************************************************/
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static unsigned ZDICT_NbCommonBytes (register size_t val)
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{
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    if (MEM_isLittleEndian()) {
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        if (MEM_64bits()) {
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#       if defined(_MSC_VER) && defined(_WIN64)
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            unsigned long r = 0;
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            _BitScanForward64( &r, (U64)val );
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            return (unsigned)(r>>3);
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#       elif defined(__GNUC__) && (__GNUC__ >= 3)
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            return (__builtin_ctzll((U64)val) >> 3);
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#       else
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            static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 };
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            return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
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#       endif
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        } else { /* 32 bits */
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#       if defined(_MSC_VER)
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            unsigned long r=0;
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            _BitScanForward( &r, (U32)val );
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            return (unsigned)(r>>3);
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#       elif defined(__GNUC__) && (__GNUC__ >= 3)
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            return (__builtin_ctz((U32)val) >> 3);
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#       else
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            static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 };
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            return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
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#       endif
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        }
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    } else {  /* Big Endian CPU */
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        if (MEM_64bits()) {
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#       if defined(_MSC_VER) && defined(_WIN64)
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            unsigned long r = 0;
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            _BitScanReverse64( &r, val );
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            return (unsigned)(r>>3);
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#       elif defined(__GNUC__) && (__GNUC__ >= 3)
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            return (__builtin_clzll(val) >> 3);
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#       else
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            unsigned r;
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            const unsigned n32 = sizeof(size_t)*4;   /* calculate this way due to compiler complaining in 32-bits mode */
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            if (!(val>>n32)) { r=4; } else { r=0; val>>=n32; }
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            if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; }
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            r += (!val);
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            return r;
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#       endif
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        } else { /* 32 bits */
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#       if defined(_MSC_VER)
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            unsigned long r = 0;
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            _BitScanReverse( &r, (unsigned long)val );
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            return (unsigned)(r>>3);
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#       elif defined(__GNUC__) && (__GNUC__ >= 3)
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            return (__builtin_clz((U32)val) >> 3);
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#       else
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            unsigned r;
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            if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
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            r += (!val);
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            return r;
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#       endif
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    }   }
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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+ZDICT_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)
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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 length;
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    size_t maxLength = LLIMIT;
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    size_t pos = 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 u16 = MEM_read16(b+pos+4);
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        U32 u, e = 6;
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        while (MEM_read16(b+pos+e) == u16) e+=2 ;
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        if (b[pos+e] == b[pos+e-1]) e++;
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        for (u=1; u<e; 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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    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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    /* look backward */
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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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    /* 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 searchLength;
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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 >= %u at pos %7u  ", (U32)(end-start), MINMATCHLENGTH, (U32)pos);
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						|
        DISPLAYLEVEL(4, "\n");
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						|
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						|
        for (searchLength = MINMATCHLENGTH ; ; searchLength++) {
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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;
 | 
						|
            for (id =refinedStart; id < refinedEnd; id++) {
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						|
                if (b[ suffix[id] + searchLength] != 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] + searchLength];
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                    currentCount = 0;
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                }
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						|
                currentCount ++;
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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;
 | 
						|
        }
 | 
						|
 | 
						|
        /* evaluate gain based on new ref */
 | 
						|
        start = refinedStart;
 | 
						|
        pos = suffix[refinedStart];
 | 
						|
        end = start;
 | 
						|
        memset(lengthList, 0, sizeof(lengthList));
 | 
						|
 | 
						|
        /* look forward */
 | 
						|
        do {
 | 
						|
            end++;
 | 
						|
            length = ZDICT_count(b + pos, b + suffix[end]);
 | 
						|
            if (length >= LLIMIT) length = LLIMIT-1;
 | 
						|
            lengthList[length]++;
 | 
						|
        } while (length >=MINMATCHLENGTH);
 | 
						|
 | 
						|
        /* look backward */
 | 
						|
        do {
 | 
						|
            length = ZDICT_count(b + pos, b + suffix[start-1]);
 | 
						|
            if (length >= LLIMIT) length = LLIMIT-1;
 | 
						|
            lengthList[length]++;
 | 
						|
            if (length >=MINMATCHLENGTH) start--;
 | 
						|
        } while(length >= MINMATCHLENGTH);
 | 
						|
 | 
						|
        /* largest useful length */
 | 
						|
        memset(cumulLength, 0, sizeof(cumulLength));
 | 
						|
        cumulLength[maxLength-1] = lengthList[maxLength-1];
 | 
						|
        for (i=(int)(maxLength-2); i>=0; i--)
 | 
						|
            cumulLength[i] = cumulLength[i+1] + lengthList[i];
 | 
						|
 | 
						|
        for (i=LLIMIT-1; i>=MINMATCHLENGTH; i--) if (cumulLength[i]>=minRatio) break;
 | 
						|
        maxLength = i;
 | 
						|
 | 
						|
        /* reduce maxLength in case of final into repetitive data */
 | 
						|
        {   U32 l = (U32)maxLength;
 | 
						|
            BYTE const c = b[pos + maxLength-1];
 | 
						|
            while (b[pos+l-2]==c) l--;
 | 
						|
            maxLength = l;
 | 
						|
        }
 | 
						|
        if (maxLength < MINMATCHLENGTH) return solution;   /* skip : no long-enough solution */
 | 
						|
 | 
						|
        /* calculate savings */
 | 
						|
        savings[5] = 0;
 | 
						|
        for (i=MINMATCHLENGTH; i<=(int)maxLength; i++)
 | 
						|
            savings[i] = savings[i-1] + (lengthList[i] * (i-3));
 | 
						|
 | 
						|
        DISPLAYLEVEL(4, "Selected ref at position %u, of length %u : saves %u (ratio: %.2f)  \n",
 | 
						|
                     (U32)pos, (U32)maxLength, savings[maxLength], (double)savings[maxLength] / maxLength);
 | 
						|
 | 
						|
        solution.pos = (U32)pos;
 | 
						|
        solution.length = (U32)maxLength;
 | 
						|
        solution.savings = savings[maxLength];
 | 
						|
 | 
						|
        /* mark positions done */
 | 
						|
        {   U32 id;
 | 
						|
            for (id=start; id<end; id++) {
 | 
						|
                U32 p, pEnd;
 | 
						|
                U32 const testedPos = suffix[id];
 | 
						|
                if (testedPos == pos)
 | 
						|
                    length = solution.length;
 | 
						|
                else {
 | 
						|
                    length = ZDICT_count(b+pos, b+testedPos);
 | 
						|
                    if (length > solution.length) length = solution.length;
 | 
						|
                }
 | 
						|
                pEnd = (U32)(testedPos + length);
 | 
						|
                for (p=testedPos; p<pEnd; p++)
 | 
						|
                    doneMarks[p] = 1;
 | 
						|
    }   }   }
 | 
						|
 | 
						|
    return solution;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/*! ZDICT_checkMerge
 | 
						|
    check if dictItem can be merged, do it if possible
 | 
						|
    @return : id of destination elt, 0 if not merged
 | 
						|
*/
 | 
						|
static U32 ZDICT_checkMerge(dictItem* table, dictItem elt, U32 eltNbToSkip)
 | 
						|
{
 | 
						|
    const U32 tableSize = table->pos;
 | 
						|
    const U32 max = elt.pos + (elt.length-1);
 | 
						|
 | 
						|
    /* tail overlap */
 | 
						|
    U32 u; for (u=1; u<tableSize; u++) {
 | 
						|
        if (u==eltNbToSkip) continue;
 | 
						|
        if ((table[u].pos > elt.pos) && (table[u].pos < max)) {  /* overlap */
 | 
						|
            /* append */
 | 
						|
            U32 addedLength = table[u].pos - elt.pos;
 | 
						|
            table[u].length += addedLength;
 | 
						|
            table[u].pos = elt.pos;
 | 
						|
            table[u].savings += elt.savings * addedLength / elt.length;   /* rough approx */
 | 
						|
            table[u].savings += elt.length / 8;    /* rough approx */
 | 
						|
            elt = table[u];
 | 
						|
            while ((u>1) && (table[u-1].savings < elt.savings))
 | 
						|
                table[u] = table[u-1], u--;
 | 
						|
            table[u] = elt;
 | 
						|
            return u;
 | 
						|
    }   }
 | 
						|
 | 
						|
    /* front overlap */
 | 
						|
    for (u=1; u<tableSize; u++) {
 | 
						|
        if (u==eltNbToSkip) continue;
 | 
						|
        if ((table[u].pos + table[u].length > elt.pos) && (table[u].pos < elt.pos)) {  /* overlap */
 | 
						|
            /* append */
 | 
						|
            int addedLength = (elt.pos + elt.length) - (table[u].pos + table[u].length);
 | 
						|
            table[u].savings += elt.length / 8;    /* rough approx */
 | 
						|
            if (addedLength > 0) {   /* otherwise, already included */
 | 
						|
                table[u].length += addedLength;
 | 
						|
                table[u].savings += elt.savings * addedLength / elt.length;   /* rough approx */
 | 
						|
            }
 | 
						|
            elt = table[u];
 | 
						|
            while ((u>1) && (table[u-1].savings < elt.savings))
 | 
						|
                table[u] = table[u-1], u--;
 | 
						|
            table[u] = elt;
 | 
						|
            return u;
 | 
						|
    }   }
 | 
						|
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static void ZDICT_removeDictItem(dictItem* table, U32 id)
 | 
						|
{
 | 
						|
    /* convention : first element is nb of elts */
 | 
						|
    U32 const max = table->pos;
 | 
						|
    U32 u;
 | 
						|
    if (!id) return;   /* protection, should never happen */
 | 
						|
    for (u=id; u<max-1; u++)
 | 
						|
        table[u] = table[u+1];
 | 
						|
    table->pos--;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static void ZDICT_insertDictItem(dictItem* table, U32 maxSize, dictItem elt)
 | 
						|
{
 | 
						|
    /* merge if possible */
 | 
						|
    U32 mergeId = ZDICT_checkMerge(table, elt, 0);
 | 
						|
    if (mergeId) {
 | 
						|
        U32 newMerge = 1;
 | 
						|
        while (newMerge) {
 | 
						|
            newMerge = ZDICT_checkMerge(table, table[mergeId], mergeId);
 | 
						|
            if (newMerge) ZDICT_removeDictItem(table, mergeId);
 | 
						|
            mergeId = newMerge;
 | 
						|
        }
 | 
						|
        return;
 | 
						|
    }
 | 
						|
 | 
						|
    /* insert */
 | 
						|
    {   U32 current;
 | 
						|
        U32 nextElt = table->pos;
 | 
						|
        if (nextElt >= maxSize) nextElt = maxSize-1;
 | 
						|
        current = nextElt-1;
 | 
						|
        while (table[current].savings < elt.savings) {
 | 
						|
            table[current+1] = table[current];
 | 
						|
            current--;
 | 
						|
        }
 | 
						|
        table[current+1] = elt;
 | 
						|
        table->pos = nextElt+1;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static U32 ZDICT_dictSize(const dictItem* dictList)
 | 
						|
{
 | 
						|
    U32 u, dictSize = 0;
 | 
						|
    for (u=1; u<dictList[0].pos; u++)
 | 
						|
        dictSize += dictList[u].length;
 | 
						|
    return dictSize;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static size_t ZDICT_trainBuffer(dictItem* dictList, U32 dictListSize,
 | 
						|
                            const void* const buffer, const size_t bufferSize,   /* buffer must end with noisy guard band */
 | 
						|
                            const size_t* fileSizes, unsigned nbFiles,
 | 
						|
                            U32 shiftRatio, unsigned maxDictSize)
 | 
						|
{
 | 
						|
    int* const suffix0 = (int*)malloc((bufferSize+2)*sizeof(*suffix0));
 | 
						|
    int* const suffix = suffix0+1;
 | 
						|
    U32* reverseSuffix = (U32*)malloc((bufferSize)*sizeof(*reverseSuffix));
 | 
						|
    BYTE* doneMarks = (BYTE*)malloc((bufferSize+16)*sizeof(*doneMarks));   /* +16 for overflow security */
 | 
						|
    U32* filePos = (U32*)malloc(nbFiles * sizeof(*filePos));
 | 
						|
    U32 minRatio = nbFiles >> shiftRatio;
 | 
						|
    int divSuftSortResult;
 | 
						|
    size_t result = 0;
 | 
						|
 | 
						|
    /* init */
 | 
						|
    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);
 | 
						|
 | 
						|
    /* sort */
 | 
						|
    DISPLAYLEVEL(2, "sorting %u files of total size %u MB ...\n", nbFiles, (U32)(bufferSize>>20));
 | 
						|
    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;
 | 
						|
        /* build file pos */
 | 
						|
        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);
 | 
						|
            if (solution.length==0) { cursor++; continue; }
 | 
						|
            ZDICT_insertDictItem(dictList, dictListSize, solution);
 | 
						|
            cursor += solution.length;
 | 
						|
            DISPLAYUPDATE(2, "\r%4.2f %% \r", (double)cursor / bufferSize * 100);
 | 
						|
    }   }
 | 
						|
 | 
						|
    /* 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 > maxDictSize) break;
 | 
						|
        }
 | 
						|
        dictList->pos = n;
 | 
						|
    }
 | 
						|
 | 
						|
_cleanup:
 | 
						|
    free(suffix0);
 | 
						|
    free(reverseSuffix);
 | 
						|
    free(doneMarks);
 | 
						|
    free(filePos);
 | 
						|
    return result;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static void ZDICT_fillNoise(void* buffer, size_t length)
 | 
						|
{
 | 
						|
    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_CCtx* ref;
 | 
						|
    ZSTD_CCtx* zc;
 | 
						|
    void* workPlace;   /* must be ZSTD_BLOCKSIZE_MAX allocated */
 | 
						|
} EStats_ress_t;
 | 
						|
 | 
						|
#define MAXREPOFFSET 1024
 | 
						|
 | 
						|
static void ZDICT_countEStats(EStats_ress_t esr,
 | 
						|
                            U32* countLit, U32* offsetcodeCount, U32* matchlengthCount, U32* litlengthCount, U32* repOffsets,
 | 
						|
                            const void* src, size_t srcSize)
 | 
						|
{
 | 
						|
    size_t cSize;
 | 
						|
 | 
						|
    if (srcSize > ZSTD_BLOCKSIZE_MAX) srcSize = ZSTD_BLOCKSIZE_MAX;   /* protection vs large samples */
 | 
						|
	{	size_t const errorCode = ZSTD_copyCCtx(esr.zc, esr.ref);
 | 
						|
		if (ZSTD_isError(errorCode)) { DISPLAYLEVEL(1, "warning : ZSTD_copyCCtx failed \n"); return; }
 | 
						|
	}
 | 
						|
    cSize = ZSTD_compressBlock(esr.zc, esr.workPlace, ZSTD_BLOCKSIZE_MAX, src, srcSize);
 | 
						|
    if (ZSTD_isError(cSize)) { DISPLAYLEVEL(1, "warning : could not compress sample size %u \n", (U32)srcSize); return; }
 | 
						|
 | 
						|
    if (cSize) {  /* if == 0; block is not compressible */
 | 
						|
        const seqStore_t* seqStorePtr = ZSTD_getSeqStore(esr.zc);
 | 
						|
 | 
						|
        /* literals stats */
 | 
						|
        {   const BYTE* bytePtr;
 | 
						|
            for(bytePtr = seqStorePtr->litStart; bytePtr < seqStorePtr->lit; bytePtr++)
 | 
						|
                countLit[*bytePtr]++;
 | 
						|
        }
 | 
						|
 | 
						|
        /* seqStats */
 | 
						|
        {   size_t const nbSeq = (size_t)(seqStorePtr->offset - seqStorePtr->offsetStart);
 | 
						|
            ZSTD_seqToCodes(seqStorePtr, nbSeq);
 | 
						|
 | 
						|
            {   const BYTE* codePtr = seqStorePtr->offCodeStart;
 | 
						|
                size_t u;
 | 
						|
                for (u=0; u<nbSeq; u++) offsetcodeCount[codePtr[u]]++;
 | 
						|
            }
 | 
						|
 | 
						|
            {   const BYTE* codePtr = seqStorePtr->mlCodeStart;
 | 
						|
                size_t u;
 | 
						|
                for (u=0; u<nbSeq; u++) matchlengthCount[codePtr[u]]++;
 | 
						|
            }
 | 
						|
 | 
						|
            {   const BYTE* codePtr = seqStorePtr->llCodeStart;
 | 
						|
                size_t u;
 | 
						|
                for (u=0; u<nbSeq; u++) litlengthCount[codePtr[u]]++;
 | 
						|
        }   }
 | 
						|
 | 
						|
        /* rep offsets */
 | 
						|
        {   const U32* const offsetPtr = seqStorePtr->offsetStart;
 | 
						|
            U32 offset1 = offsetPtr[0] - 3;
 | 
						|
            U32 offset2 = offsetPtr[1] - 3;
 | 
						|
            if (offset1 >= MAXREPOFFSET) offset1 = 0;
 | 
						|
            if (offset2 >= MAXREPOFFSET) offset2 = 0;
 | 
						|
            repOffsets[offset1] += 3;
 | 
						|
            repOffsets[offset2] += 1;
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
static size_t ZDICT_maxSampleSize(const size_t* fileSizes, unsigned nbFiles)
 | 
						|
{
 | 
						|
    unsigned u;
 | 
						|
    size_t max=0;
 | 
						|
    for (u=0; u<nbFiles; u++)
 | 
						|
        if (max < fileSizes[u]) max = fileSizes[u];
 | 
						|
    return max;
 | 
						|
}
 | 
						|
*/
 | 
						|
 | 
						|
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;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
#define OFFCODE_MAX 18  /* only applicable to first block */
 | 
						|
static size_t ZDICT_analyzeEntropy(void*  dstBuffer, size_t maxDstSize,
 | 
						|
                                 unsigned compressionLevel,
 | 
						|
                           const void*  srcBuffer, const size_t* fileSizes, unsigned nbFiles,
 | 
						|
                           const void* dictBuffer, size_t  dictBufferSize)
 | 
						|
{
 | 
						|
    U32 countLit[256];
 | 
						|
    HUF_CREATE_STATIC_CTABLE(hufTable, 255);
 | 
						|
    U32 offcodeCount[OFFCODE_MAX+1];
 | 
						|
    short offcodeNCount[OFFCODE_MAX+1];
 | 
						|
    U32 matchLengthCount[MaxML+1];
 | 
						|
    short matchLengthNCount[MaxML+1];
 | 
						|
    U32 litLengthCount[MaxLL+1];
 | 
						|
    short litLengthNCount[MaxLL+1];
 | 
						|
    U32 repOffset[MAXREPOFFSET] = { 0 };
 | 
						|
    offsetCount_t bestRepOffset[ZSTD_REP_NUM+1];
 | 
						|
    EStats_ress_t esr;
 | 
						|
    ZSTD_parameters params;
 | 
						|
    U32 u, huffLog = 12, 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;
 | 
						|
    BYTE* dstPtr = (BYTE*)dstBuffer;
 | 
						|
 | 
						|
    /* init */
 | 
						|
    for (u=0; u<256; u++) countLit[u]=1;   /* any character must be described */
 | 
						|
    for (u=0; u<=OFFCODE_MAX; u++) offcodeCount[u]=1;
 | 
						|
    for (u=0; u<=MaxML; u++) matchLengthCount[u]=1;
 | 
						|
    for (u=0; u<=MaxLL; u++) litLengthCount[u]=1;
 | 
						|
    repOffset[1] = repOffset[4] = repOffset[8] = 1;
 | 
						|
    memset(bestRepOffset, 0, sizeof(bestRepOffset));
 | 
						|
    esr.ref = ZSTD_createCCtx();
 | 
						|
    esr.zc = ZSTD_createCCtx();
 | 
						|
    esr.workPlace = malloc(ZSTD_BLOCKSIZE_MAX);
 | 
						|
    if (!esr.ref || !esr.zc || !esr.workPlace) {
 | 
						|
            eSize = ERROR(memory_allocation);
 | 
						|
            DISPLAYLEVEL(1, "Not enough memory");
 | 
						|
            goto _cleanup;
 | 
						|
    }
 | 
						|
    if (compressionLevel==0) compressionLevel=g_compressionLevel_default;
 | 
						|
    params.cParams = ZSTD_getCParams(compressionLevel, averageSampleSize, dictBufferSize);
 | 
						|
    //params.cParams.strategy = ZSTD_greedy;
 | 
						|
    params.fParams.contentSizeFlag = 0;
 | 
						|
	{	size_t const beginResult = ZSTD_compressBegin_advanced(esr.ref, dictBuffer, dictBufferSize, params, 0);
 | 
						|
		if (ZSTD_isError(beginResult)) {
 | 
						|
			eSize = ERROR(GENERIC);
 | 
						|
			DISPLAYLEVEL(1, "error : ZSTD_compressBegin_advanced failed ");
 | 
						|
			goto _cleanup;
 | 
						|
	}	}
 | 
						|
 | 
						|
    /* collect stats on all files */
 | 
						|
    for (u=0; u<nbFiles; u++) {
 | 
						|
        ZDICT_countEStats(esr,
 | 
						|
                        countLit, offcodeCount, matchLengthCount, litLengthCount, repOffset,
 | 
						|
           (const char*)srcBuffer + pos, fileSizes[u]);
 | 
						|
        pos += fileSizes[u];
 | 
						|
    }
 | 
						|
 | 
						|
    /* analyze */
 | 
						|
    errorCode = HUF_buildCTable (hufTable, countLit, 255, huffLog);
 | 
						|
    if (HUF_isError(errorCode)) {
 | 
						|
        eSize = ERROR(GENERIC);
 | 
						|
        DISPLAYLEVEL(1, "HUF_buildCTable error");
 | 
						|
        goto _cleanup;
 | 
						|
    }
 | 
						|
    huffLog = (U32)errorCode;
 | 
						|
 | 
						|
    /* 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<=OFFCODE_MAX; u++) total+=offcodeCount[u];
 | 
						|
    errorCode = FSE_normalizeCount(offcodeNCount, Offlog, offcodeCount, total, OFFCODE_MAX);
 | 
						|
    if (FSE_isError(errorCode)) {
 | 
						|
        eSize = ERROR(GENERIC);
 | 
						|
        DISPLAYLEVEL(1, "FSE_normalizeCount error with offcodeCount");
 | 
						|
        goto _cleanup;
 | 
						|
    }
 | 
						|
    Offlog = (U32)errorCode;
 | 
						|
 | 
						|
    total=0; for (u=0; u<=MaxML; u++) total+=matchLengthCount[u];
 | 
						|
    errorCode = FSE_normalizeCount(matchLengthNCount, mlLog, matchLengthCount, total, MaxML);
 | 
						|
    if (FSE_isError(errorCode)) {
 | 
						|
        eSize = ERROR(GENERIC);
 | 
						|
        DISPLAYLEVEL(1, "FSE_normalizeCount error with matchLengthCount");
 | 
						|
        goto _cleanup;
 | 
						|
    }
 | 
						|
    mlLog = (U32)errorCode;
 | 
						|
 | 
						|
    total=0; for (u=0; u<=MaxLL; u++) total+=litLengthCount[u];
 | 
						|
    errorCode = FSE_normalizeCount(litLengthNCount, llLog, litLengthCount, total, MaxLL);
 | 
						|
    if (FSE_isError(errorCode)) {
 | 
						|
        eSize = ERROR(GENERIC);
 | 
						|
        DISPLAYLEVEL(1, "FSE_normalizeCount error with litLengthCount");
 | 
						|
        goto _cleanup;
 | 
						|
    }
 | 
						|
    llLog = (U32)errorCode;
 | 
						|
 | 
						|
 | 
						|
    /* write result to buffer */
 | 
						|
    {   size_t const hhSize = HUF_writeCTable(dstPtr, maxDstSize, hufTable, 255, huffLog);
 | 
						|
        if (HUF_isError(hhSize)) {
 | 
						|
            eSize = ERROR(GENERIC);
 | 
						|
            DISPLAYLEVEL(1, "HUF_writeCTable error");
 | 
						|
            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 = ERROR(GENERIC);
 | 
						|
            DISPLAYLEVEL(1, "FSE_writeNCount error with offcodeNCount");
 | 
						|
            goto _cleanup;
 | 
						|
        }
 | 
						|
        dstPtr += ohSize;
 | 
						|
        maxDstSize -= ohSize;
 | 
						|
        eSize += ohSize;
 | 
						|
    }
 | 
						|
 | 
						|
    {   size_t const mhSize = FSE_writeNCount(dstPtr, maxDstSize, matchLengthNCount, MaxML, mlLog);
 | 
						|
        if (FSE_isError(mhSize)) {
 | 
						|
            eSize = ERROR(GENERIC);
 | 
						|
            DISPLAYLEVEL(1, "FSE_writeNCount error with matchLengthNCount");
 | 
						|
            goto _cleanup;
 | 
						|
        }
 | 
						|
        dstPtr += mhSize;
 | 
						|
        maxDstSize -= mhSize;
 | 
						|
        eSize += mhSize;
 | 
						|
    }
 | 
						|
 | 
						|
    {   size_t const lhSize = FSE_writeNCount(dstPtr, maxDstSize, litLengthNCount, MaxLL, llLog);
 | 
						|
        if (FSE_isError(lhSize)) {
 | 
						|
            eSize = ERROR(GENERIC);
 | 
						|
            DISPLAYLEVEL(1, "FSE_writeNCount error with litlengthNCount");
 | 
						|
            goto _cleanup;
 | 
						|
        }
 | 
						|
        dstPtr += lhSize;
 | 
						|
        maxDstSize -= lhSize;
 | 
						|
        eSize += lhSize;
 | 
						|
    }
 | 
						|
 | 
						|
    if (maxDstSize<12) {
 | 
						|
        eSize = ERROR(GENERIC);
 | 
						|
        DISPLAYLEVEL(1, "not enough space to write RepOffsets");
 | 
						|
        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
 | 
						|
    dstPtr += 12;
 | 
						|
    eSize += 12;
 | 
						|
 | 
						|
_cleanup:
 | 
						|
    ZSTD_freeCCtx(esr.ref);
 | 
						|
    ZSTD_freeCCtx(esr.zc);
 | 
						|
    free(esr.workPlace);
 | 
						|
 | 
						|
    return eSize;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
#define DIB_FASTSEGMENTSIZE 64
 | 
						|
/*! ZDICT_fastSampling()  (based on an idea proposed by Giuseppe Ottaviano) :
 | 
						|
    Fill `dictBuffer` with stripes of size DIB_FASTSEGMENTSIZE from `samplesBuffer`,
 | 
						|
    up to `dictSize`.
 | 
						|
    Filling starts from the end of `dictBuffer`, down to maximum possible.
 | 
						|
    if `dictSize` is not a multiply of DIB_FASTSEGMENTSIZE, some bytes at beginning of `dictBuffer` won't be used.
 | 
						|
    @return : amount of data written into `dictBuffer`,
 | 
						|
              or an error code
 | 
						|
*/
 | 
						|
static size_t ZDICT_fastSampling(void* dictBuffer, size_t dictSize,
 | 
						|
                         const void* samplesBuffer, size_t samplesSize)
 | 
						|
{
 | 
						|
    char* dstPtr = (char*)dictBuffer + dictSize;
 | 
						|
    const char* srcPtr = (const char*)samplesBuffer;
 | 
						|
    size_t const nbSegments = dictSize / DIB_FASTSEGMENTSIZE;
 | 
						|
    size_t segNb, interSize;
 | 
						|
 | 
						|
    if (nbSegments <= 2) return ERROR(srcSize_wrong);
 | 
						|
    if (samplesSize < dictSize) return ERROR(srcSize_wrong);
 | 
						|
 | 
						|
    /* first and last segments are part of dictionary, in case they contain interesting header/footer */
 | 
						|
    dstPtr -= DIB_FASTSEGMENTSIZE;
 | 
						|
    memcpy(dstPtr, srcPtr, DIB_FASTSEGMENTSIZE);
 | 
						|
    dstPtr -= DIB_FASTSEGMENTSIZE;
 | 
						|
    memcpy(dstPtr, srcPtr+samplesSize-DIB_FASTSEGMENTSIZE, DIB_FASTSEGMENTSIZE);
 | 
						|
 | 
						|
    /* regularly copy a segment */
 | 
						|
    interSize = (samplesSize - nbSegments*DIB_FASTSEGMENTSIZE) / (nbSegments-1);
 | 
						|
    srcPtr += DIB_FASTSEGMENTSIZE;
 | 
						|
    for (segNb=2; segNb < nbSegments; segNb++) {
 | 
						|
        srcPtr += interSize;
 | 
						|
        dstPtr -= DIB_FASTSEGMENTSIZE;
 | 
						|
        memcpy(dstPtr, srcPtr, DIB_FASTSEGMENTSIZE);
 | 
						|
        srcPtr += DIB_FASTSEGMENTSIZE;
 | 
						|
    }
 | 
						|
 | 
						|
    return nbSegments * DIB_FASTSEGMENTSIZE;
 | 
						|
}
 | 
						|
 | 
						|
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)
 | 
						|
{
 | 
						|
    size_t hSize;
 | 
						|
    unsigned const compressionLevel = (params.compressionLevel == 0) ? g_compressionLevel_default : params.compressionLevel;
 | 
						|
 | 
						|
    /* dictionary header */
 | 
						|
    MEM_writeLE32(dictBuffer, ZSTD_DICT_MAGIC);
 | 
						|
    {   U64 const randomID = XXH64((char*)dictBuffer + dictBufferCapacity - dictContentSize, dictContentSize, 0);
 | 
						|
        U32 const dictID = params.dictID ? params.dictID : (U32)(randomID>>11);
 | 
						|
        MEM_writeLE32((char*)dictBuffer+4, dictID);
 | 
						|
    }
 | 
						|
    hSize = 8;
 | 
						|
 | 
						|
    /* entropy tables */
 | 
						|
    DISPLAYLEVEL(2, "\r%70s\r", "");   /* clean display line */
 | 
						|
    DISPLAYLEVEL(2, "statistics ... \n");
 | 
						|
    hSize += ZDICT_analyzeEntropy((char*)dictBuffer+hSize, dictBufferCapacity-hSize,
 | 
						|
                                  compressionLevel,
 | 
						|
                                  samplesBuffer, samplesSizes, nbSamples,
 | 
						|
                                  (char*)dictBuffer + dictBufferCapacity - dictContentSize, dictContentSize);
 | 
						|
 | 
						|
    if (hSize + dictContentSize < dictBufferCapacity)
 | 
						|
        memmove((char*)dictBuffer + hSize, (char*)dictBuffer + dictBufferCapacity - dictContentSize, dictContentSize);
 | 
						|
    return MIN(dictBufferCapacity, hSize+dictContentSize);
 | 
						|
}
 | 
						|
 | 
						|
#define DIB_MINSAMPLESSIZE (DIB_FASTSEGMENTSIZE*3)
 | 
						|
/*! ZDICT_trainFromBuffer_unsafe() :
 | 
						|
*   `samplesBuffer` must be followed by noisy guard band.
 | 
						|
*   @return : size of dictionary.
 | 
						|
*/
 | 
						|
size_t ZDICT_trainFromBuffer_unsafe(
 | 
						|
                            void* dictBuffer, size_t maxDictSize,
 | 
						|
                            const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
 | 
						|
                            ZDICT_params_t params)
 | 
						|
{
 | 
						|
    U32 const dictListSize = MAX( MAX(DICTLISTSIZE, nbSamples), (U32)(maxDictSize/16));
 | 
						|
    dictItem* const dictList = (dictItem*)malloc(dictListSize * sizeof(*dictList));
 | 
						|
    unsigned selectivity = params.selectivityLevel;
 | 
						|
    size_t const targetDictSize = maxDictSize;
 | 
						|
    size_t sBuffSize;
 | 
						|
    size_t dictSize = 0;
 | 
						|
 | 
						|
    /* checks */
 | 
						|
    if (maxDictSize <= g_provision_entropySize + g_min_fast_dictContent) return ERROR(dstSize_tooSmall);
 | 
						|
    if (!dictList) return ERROR(memory_allocation);
 | 
						|
 | 
						|
    /* init */
 | 
						|
    { unsigned u; for (u=0, sBuffSize=0; u<nbSamples; u++) sBuffSize += samplesSizes[u]; }
 | 
						|
    if (sBuffSize < DIB_MINSAMPLESSIZE) return 0;   /* not enough source to create dictionary */
 | 
						|
    ZDICT_initDictItem(dictList);
 | 
						|
    g_displayLevel = params.notificationLevel;
 | 
						|
    if (selectivity==0) selectivity = g_selectivity_default;
 | 
						|
 | 
						|
    /* build dictionary */
 | 
						|
    if (selectivity>1) {  /* selectivity == 1 => fast mode */
 | 
						|
        ZDICT_trainBuffer(dictList, dictListSize,
 | 
						|
                        samplesBuffer, sBuffSize,
 | 
						|
                        samplesSizes, nbSamples,
 | 
						|
                        selectivity, (U32)targetDictSize);
 | 
						|
 | 
						|
        /* display best matches */
 | 
						|
        if (g_displayLevel>= 3) {
 | 
						|
            U32 const nb = 25;
 | 
						|
            U32 const dictContentSize = ZDICT_dictSize(dictList);
 | 
						|
            U32 u;
 | 
						|
            DISPLAYLEVEL(3, "\n %u segments found, of total size %u \n", dictList[0].pos, dictContentSize);
 | 
						|
            DISPLAYLEVEL(3, "list %u best segments \n", nb);
 | 
						|
            for (u=1; u<=nb; u++) {
 | 
						|
                U32 p = dictList[u].pos;
 | 
						|
                U32 l = dictList[u].length;
 | 
						|
                U32 d = MIN(40, l);
 | 
						|
                DISPLAYLEVEL(3, "%3u:%3u bytes at pos %8u, savings %7u bytes |",
 | 
						|
                             u, l, p, dictList[u].savings);
 | 
						|
                ZDICT_printHex(3, (const char*)samplesBuffer+p, d);
 | 
						|
                DISPLAYLEVEL(3, "| \n");
 | 
						|
    }   }   }
 | 
						|
 | 
						|
    /* create dictionary */
 | 
						|
    {   U32 dictContentSize = ZDICT_dictSize(dictList);
 | 
						|
 | 
						|
        /* 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) return ERROR(GENERIC);   /* should not happen */
 | 
						|
                memcpy(ptr, (const char*)samplesBuffer+dictList[u].pos, l);
 | 
						|
        }   }
 | 
						|
 | 
						|
        /* fast mode dict content */
 | 
						|
        if (selectivity==1) {  /* note could also be used to complete a dictionary, but not necessarily better */
 | 
						|
            DISPLAYLEVEL(3, "\r%70s\r", "");   /* clean display line */
 | 
						|
            DISPLAYLEVEL(3, "Adding %u KB with fast sampling \n", (U32)(targetDictSize>>10));
 | 
						|
            dictContentSize = (U32)ZDICT_fastSampling(dictBuffer, targetDictSize,
 | 
						|
                                                      samplesBuffer, sBuffSize);
 | 
						|
        }
 | 
						|
 | 
						|
        dictSize = ZDICT_addEntropyTablesFromBuffer_advanced(dictBuffer, dictContentSize, maxDictSize,
 | 
						|
                                                             samplesBuffer, samplesSizes, nbSamples,
 | 
						|
                                                             params);
 | 
						|
    }
 | 
						|
 | 
						|
    /* clean up */
 | 
						|
    free(dictList);
 | 
						|
    return dictSize;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/* issue : samplesBuffer need to be followed by a noisy guard band.
 | 
						|
*  work around : duplicate the buffer, and add the noise */
 | 
						|
size_t ZDICT_trainFromBuffer_advanced(void* dictBuffer, size_t dictBufferCapacity,
 | 
						|
                                      const void* samplesBuffer, const size_t* samplesSizes, unsigned nbSamples,
 | 
						|
                                      ZDICT_params_t params)
 | 
						|
{
 | 
						|
    void* newBuff;
 | 
						|
    size_t sBuffSize;
 | 
						|
 | 
						|
    { unsigned u; for (u=0, sBuffSize=0; u<nbSamples; u++) sBuffSize += samplesSizes[u]; }
 | 
						|
    if (sBuffSize==0) return 0;   /* empty 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 */
 | 
						|
 | 
						|
    { size_t const result = ZDICT_trainFromBuffer_unsafe(
 | 
						|
                                        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_params_t params;
 | 
						|
    memset(¶ms, 0, sizeof(params));
 | 
						|
    return ZDICT_trainFromBuffer_advanced(dictBuffer, dictBufferCapacity,
 | 
						|
                                          samplesBuffer, samplesSizes, nbSamples,
 | 
						|
                                          params);
 | 
						|
}
 | 
						|
 | 
						|
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);
 | 
						|
}
 |