X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=deps%2Flibchdr%2Fdeps%2Fzstd-1.5.5%2Fprograms%2Fdatagen.c;fp=deps%2Flibchdr%2Fdeps%2Fzstd-1.5.5%2Fprograms%2Fdatagen.c;h=ddc690bb1b7599b416a68d5b72a74c48980c64cc;hb=648db22b0750712da893c306efcc8e4b2d3a4e3c;hp=0000000000000000000000000000000000000000;hpb=e2fb1389dc12376acb84e4993ed3b08760257252;p=pcsx_rearmed.git diff --git a/deps/libchdr/deps/zstd-1.5.5/programs/datagen.c b/deps/libchdr/deps/zstd-1.5.5/programs/datagen.c new file mode 100644 index 00000000..ddc690bb --- /dev/null +++ b/deps/libchdr/deps/zstd-1.5.5/programs/datagen.c @@ -0,0 +1,186 @@ +/* + * Copyright (c) Meta Platforms, Inc. and affiliates. + * All rights reserved. + * + * This source code is licensed under both the BSD-style license (found in the + * LICENSE file in the root directory of this source tree) and the GPLv2 (found + * in the COPYING file in the root directory of this source tree). + * You may select, at your option, one of the above-listed licenses. + */ + + + +/*-************************************ +* Dependencies +**************************************/ +#include "datagen.h" +#include "platform.h" /* SET_BINARY_MODE */ +#include /* malloc, free */ +#include /* FILE, fwrite, fprintf */ +#include /* memcpy */ +#include "../lib/common/mem.h" /* U32 */ + + +/*-************************************ +* Macros +**************************************/ +#define KB *(1 <<10) +#define MIN(a,b) ( (a) < (b) ? (a) : (b) ) + +#define RDG_DEBUG 0 +#define TRACE(...) if (RDG_DEBUG) fprintf(stderr, __VA_ARGS__ ) + + +/*-************************************ +* Local constants +**************************************/ +#define LTLOG 13 +#define LTSIZE (1<> (32 - r))) +static U32 RDG_rand(U32* src) +{ + static const U32 prime1 = 2654435761U; + static const U32 prime2 = 2246822519U; + U32 rand32 = *src; + rand32 *= prime1; + rand32 ^= prime2; + rand32 = RDG_rotl32(rand32, 13); + *src = rand32; + return rand32 >> 5; +} + +typedef U32 fixedPoint_24_8; + +static void RDG_fillLiteralDistrib(BYTE* ldt, fixedPoint_24_8 ld) +{ + BYTE const firstChar = (ld<=0.0) ? 0 : '('; + BYTE const lastChar = (ld<=0.0) ? 255 : '}'; + BYTE character = (ld<=0.0) ? 0 : '0'; + U32 u; + + if (ld<=0) ld = 0; + for (u=0; u> 8) + 1; + U32 const end = MIN ( u + weight , LTSIZE); + while (u < end) ldt[u++] = character; + character++; + if (character > lastChar) character = firstChar; + } +} + + +static BYTE RDG_genChar(U32* seed, const BYTE* ldt) +{ + U32 const id = RDG_rand(seed) & LTMASK; + return ldt[id]; /* memory-sanitizer fails here, stating "uninitialized value" when table initialized with P==0.0. Checked : table is fully initialized */ +} + + +static U32 RDG_rand15Bits (U32* seedPtr) +{ + return RDG_rand(seedPtr) & 0x7FFF; +} + +static U32 RDG_randLength(U32* seedPtr) +{ + if (RDG_rand(seedPtr) & 7) return (RDG_rand(seedPtr) & 0xF); /* small length */ + return (RDG_rand(seedPtr) & 0x1FF) + 0xF; +} + +static void RDG_genBlock(void* buffer, size_t buffSize, size_t prefixSize, + double matchProba, const BYTE* ldt, U32* seedPtr) +{ + BYTE* const buffPtr = (BYTE*)buffer; + U32 const matchProba32 = (U32)(32768 * matchProba); + size_t pos = prefixSize; + U32 prevOffset = 1; + + /* special case : sparse content */ + while (matchProba >= 1.0) { + size_t size0 = RDG_rand(seedPtr) & 3; + size0 = (size_t)1 << (16 + size0 * 2); + size0 += RDG_rand(seedPtr) & (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(seedPtr, ldt); + continue; + } + + /* init */ + if (pos==0) buffPtr[0] = RDG_genChar(seedPtr, ldt), pos=1; + + /* Generate compressible data */ + while (pos < buffSize) { + /* Select : Literal (char) or Match (within 32K) */ + if (RDG_rand15Bits(seedPtr) < matchProba32) { + /* Copy (within 32K) */ + U32 const length = RDG_randLength(seedPtr) + 4; + U32 const d = (U32) MIN(pos + length , buffSize); + U32 const repeatOffset = (RDG_rand(seedPtr) & 15) == 2; + U32 const randOffset = RDG_rand15Bits(seedPtr) + 1; + U32 const offset = repeatOffset ? prevOffset : (U32) MIN(randOffset , pos); + size_t match = pos - offset; + while (pos < d) { buffPtr[pos++] = buffPtr[match++]; /* correctly manages overlaps */ } + prevOffset = offset; + } else { + /* Literal (noise) */ + U32 const length = RDG_randLength(seedPtr); + U32 const d = (U32) MIN(pos + length, buffSize); + while (pos < d) { buffPtr[pos++] = RDG_genChar(seedPtr, ldt); } + } } +} + + +void RDG_genBuffer(void* buffer, size_t size, double matchProba, double litProba, unsigned seed) +{ + U32 seed32 = seed; + BYTE ldt[LTSIZE]; + memset(ldt, '0', sizeof(ldt)); /* yes, character '0', this is intentional */ + if (litProba<=0.0) litProba = matchProba / 4.5; + RDG_fillLiteralDistrib(ldt, (fixedPoint_24_8)(litProba * 256 + 0.001)); + RDG_genBlock(buffer, size, 0, matchProba, ldt, &seed32); +} + + +void RDG_genStdout(unsigned long long size, double matchProba, double litProba, unsigned seed) +{ + U32 seed32 = seed; + size_t const stdBlockSize = 128 KB; + size_t const stdDictSize = 32 KB; + BYTE* const buff = (BYTE*)malloc(stdDictSize + stdBlockSize); + U64 total = 0; + BYTE ldt[LTSIZE]; /* literals distribution table */ + + /* init */ + if (buff==NULL) { perror("datagen"); exit(1); } + if (litProba<=0.0) litProba = matchProba / 4.5; + memset(ldt, '0', sizeof(ldt)); /* yes, character '0', this is intentional */ + RDG_fillLiteralDistrib(ldt, (fixedPoint_24_8)(litProba * 256 + 0.001)); + SET_BINARY_MODE(stdout); + + /* Generate initial dict */ + RDG_genBlock(buff, stdDictSize, 0, matchProba, ldt, &seed32); + + /* Generate compressible data */ + while (total < size) { + size_t const genBlockSize = (size_t) (MIN (stdBlockSize, size-total)); + RDG_genBlock(buff, stdDictSize+stdBlockSize, stdDictSize, matchProba, ldt, &seed32); + total += genBlockSize; + { size_t const unused = fwrite(buff, 1, genBlockSize, stdout); (void)unused; } + /* update dict */ + memcpy(buff, buff + stdBlockSize, stdDictSize); + } + + /* cleanup */ + free(buff); +}