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v1.7.3
programs/datagen.c
218 строк
6 KB
Yann Collet
fixed minor coverity warnings
16 ноя 2016, 01:46
16 ноя 2016, 01:46
d2be69b
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/* datagen.c - compressible data generator test tool Copyright (C) Yann Collet 2012-2015 GPL v2 License This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. You can contact the author at : - LZ4 source repository : https://github.com/lz4/lz4 - Public forum : https://groups.google.com/forum/#!forum/lz4c */ /************************************** * Includes **************************************/ #include <stdlib.h> /* malloc */ #include <stdio.h> /* FILE, fwrite */ #include <string.h> /* memcpy */ /************************************** * Basic Types **************************************/ #if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */ # include <stdint.h> typedef uint8_t BYTE; typedef uint16_t U16; typedef uint32_t U32; typedef int32_t S32; typedef uint64_t U64; #else typedef unsigned char BYTE; typedef unsigned short U16; typedef unsigned int U32; typedef signed int S32; typedef unsigned long long U64; #endif /************************************** * OS-specific Includes **************************************/ #if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(_WIN32) || defined(__CYGWIN__) # include <fcntl.h> /* _O_BINARY */ # include <io.h> /* _setmode, _isatty */ # define SET_BINARY_MODE(file) _setmode(_fileno(file), _O_BINARY) #else # define SET_BINARY_MODE(file) #endif /************************************** * Constants **************************************/ #define KB *(1 <<10) #define PRIME1 2654435761U #define PRIME2 2246822519U /************************************** * Local types **************************************/ #define LTLOG 13 #define LTSIZE (1<<LTLOG) #define LTMASK (LTSIZE-1) typedef BYTE litDistribTable[LTSIZE]; /********************************************************* * Local Functions *********************************************************/ #define MIN(a,b) ( (a) < (b) ? (a) :(b) ) #define RDG_rotl32(x,r) ((x << r) | (x >> (32 - r))) static unsigned int RDG_rand(U32* src) { U32 rand32 = *src; rand32 *= PRIME1; rand32 ^= PRIME2; rand32 = RDG_rotl32(rand32, 13); *src = rand32; return rand32; } static void RDG_fillLiteralDistrib(litDistribTable lt, double ld) { BYTE const firstChar = ld <= 0.0 ? 0 : '('; BYTE const lastChar = ld <= 0.0 ? 255 : '}'; BYTE character = ld <= 0.0 ? 0 : '0'; U32 u = 0; while (u<LTSIZE) { U32 const weight = (U32)((double)(LTSIZE - u) * ld) + 1; U32 const end = MIN(u+weight, LTSIZE); while (u < end) lt[u++] = character; character++; if (character > lastChar) character = firstChar; } } static BYTE RDG_genChar(U32* seed, const litDistribTable lt) { U32 id = RDG_rand(seed) & LTMASK; return (lt[id]); } #define RDG_DICTSIZE (32 KB) #define RDG_RAND15BITS ((RDG_rand(seed) >> 3) & 32767) #define RDG_RANDLENGTH ( ((RDG_rand(seed) >> 7) & 7) ? (RDG_rand(seed) & 15) : (RDG_rand(seed) & 511) + 15) void RDG_genBlock(void* buffer, size_t buffSize, size_t prefixSize, double matchProba, litDistribTable lt, unsigned* seedPtr) { BYTE* buffPtr = (BYTE*)buffer; const U32 matchProba32 = (U32)(32768 * matchProba); size_t pos = prefixSize; U32* seed = seedPtr; /* special case */ while (matchProba >= 1.0) { size_t size0 = RDG_rand(seed) & 3; size0 = (size_t)1 << (16 + size0 * 2); size0 += RDG_rand(seed) & (size0-1); /* because size0 is power of 2*/ if (buffSize < pos + size0) { memset(buffPtr+pos, 0, buffSize-pos); return; } memset(buffPtr+pos, 0, size0); pos += size0; buffPtr[pos-1] = RDG_genChar(seed, lt); } /* init */ if (pos==0) buffPtr[0] = RDG_genChar(seed, lt), pos=1; /* Generate compressible data */ while (pos < buffSize) { /* Select : Literal (char) or Match (within 32K) */ if (RDG_RAND15BITS < matchProba32) { /* Copy (within 32K) */ size_t match; size_t d; int length = RDG_RANDLENGTH + 4; U32 offset = RDG_RAND15BITS + 1; if (offset > pos) offset = (U32)pos; match = pos - offset; d = pos + length; if (d > buffSize) d = buffSize; while (pos < d) buffPtr[pos++] = buffPtr[match++]; } else { /* Literal (noise) */ size_t d; size_t length = RDG_RANDLENGTH; d = pos + length; if (d > buffSize) d = buffSize; while (pos < d) buffPtr[pos++] = RDG_genChar(seed, lt); } } } void RDG_genBuffer(void* buffer, size_t size, double matchProba, double litProba, unsigned seed) { litDistribTable lt; if (litProba==0.0) litProba = matchProba / 4.5; RDG_fillLiteralDistrib(lt, litProba); RDG_genBlock(buffer, size, 0, matchProba, lt, &seed); } #define RDG_BLOCKSIZE (128 KB) void RDG_genOut(unsigned long long size, double matchProba, double litProba, unsigned seed) { BYTE buff[RDG_DICTSIZE + RDG_BLOCKSIZE]; U64 total = 0; size_t genBlockSize = RDG_BLOCKSIZE; litDistribTable lt; /* init */ if (litProba==0.0) litProba = matchProba / 4.5; RDG_fillLiteralDistrib(lt, litProba); SET_BINARY_MODE(stdout); /* Generate dict */ RDG_genBlock(buff, RDG_DICTSIZE, 0, matchProba, lt, &seed); /* Generate compressible data */ while (total < size) { RDG_genBlock(buff, RDG_DICTSIZE+RDG_BLOCKSIZE, RDG_DICTSIZE, matchProba, lt, &seed); if (size-total < RDG_BLOCKSIZE) genBlockSize = (size_t)(size-total); total += genBlockSize; fwrite(buff, 1, genBlockSize, stdout); /* update dict */ memcpy(buff, buff + RDG_BLOCKSIZE, RDG_DICTSIZE); } }