diff options
Diffstat (limited to 'lib/zstd')
-rw-r--r-- | lib/zstd/Makefile | 18 | ||||
-rw-r--r-- | lib/zstd/bitstream.h | 374 | ||||
-rw-r--r-- | lib/zstd/compress.c | 3484 | ||||
-rw-r--r-- | lib/zstd/decompress.c | 2528 | ||||
-rw-r--r-- | lib/zstd/entropy_common.c | 243 | ||||
-rw-r--r-- | lib/zstd/error_private.h | 53 | ||||
-rw-r--r-- | lib/zstd/fse.h | 575 | ||||
-rw-r--r-- | lib/zstd/fse_compress.c | 795 | ||||
-rw-r--r-- | lib/zstd/fse_decompress.c | 332 | ||||
-rw-r--r-- | lib/zstd/huf.h | 212 | ||||
-rw-r--r-- | lib/zstd/huf_compress.c | 770 | ||||
-rw-r--r-- | lib/zstd/huf_decompress.c | 960 | ||||
-rw-r--r-- | lib/zstd/mem.h | 151 | ||||
-rw-r--r-- | lib/zstd/zstd_common.c | 75 | ||||
-rw-r--r-- | lib/zstd/zstd_internal.h | 263 | ||||
-rw-r--r-- | lib/zstd/zstd_opt.h | 1014 |
16 files changed, 11847 insertions, 0 deletions
diff --git a/lib/zstd/Makefile b/lib/zstd/Makefile new file mode 100644 index 000000000000..dd0a359c135b --- /dev/null +++ b/lib/zstd/Makefile @@ -0,0 +1,18 @@ +obj-$(CONFIG_ZSTD_COMPRESS) += zstd_compress.o +obj-$(CONFIG_ZSTD_DECOMPRESS) += zstd_decompress.o + +ccflags-y += -O3 + +# Object files unique to zstd_compress and zstd_decompress +zstd_compress-y := fse_compress.o huf_compress.o compress.o +zstd_decompress-y := huf_decompress.o decompress.o + +# These object files are shared between the modules. +# Always add them to zstd_compress. +# Unless both zstd_compress and zstd_decompress are built in +# then also add them to zstd_decompress. +zstd_compress-y += entropy_common.o fse_decompress.o zstd_common.o + +ifneq ($(CONFIG_ZSTD_COMPRESS)$(CONFIG_ZSTD_DECOMPRESS),yy) + zstd_decompress-y += entropy_common.o fse_decompress.o zstd_common.o +endif diff --git a/lib/zstd/bitstream.h b/lib/zstd/bitstream.h new file mode 100644 index 000000000000..a826b99e1d63 --- /dev/null +++ b/lib/zstd/bitstream.h @@ -0,0 +1,374 @@ +/* + * bitstream + * Part of FSE library + * header file (to include) + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ +#ifndef BITSTREAM_H_MODULE +#define BITSTREAM_H_MODULE + +/* +* This API consists of small unitary functions, which must be inlined for best performance. +* Since link-time-optimization is not available for all compilers, +* these functions are defined into a .h to be included. +*/ + +/*-**************************************** +* Dependencies +******************************************/ +#include "error_private.h" /* error codes and messages */ +#include "mem.h" /* unaligned access routines */ + +/*========================================= +* Target specific +=========================================*/ +#define STREAM_ACCUMULATOR_MIN_32 25 +#define STREAM_ACCUMULATOR_MIN_64 57 +#define STREAM_ACCUMULATOR_MIN ((U32)(ZSTD_32bits() ? STREAM_ACCUMULATOR_MIN_32 : STREAM_ACCUMULATOR_MIN_64)) + +/*-****************************************** +* bitStream encoding API (write forward) +********************************************/ +/* bitStream can mix input from multiple sources. +* A critical property of these streams is that they encode and decode in **reverse** direction. +* So the first bit sequence you add will be the last to be read, like a LIFO stack. +*/ +typedef struct { + size_t bitContainer; + int bitPos; + char *startPtr; + char *ptr; + char *endPtr; +} BIT_CStream_t; + +ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *dstBuffer, size_t dstCapacity); +ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits); +ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC); +ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC); + +/* Start with initCStream, providing the size of buffer to write into. +* bitStream will never write outside of this buffer. +* `dstCapacity` must be >= sizeof(bitD->bitContainer), otherwise @return will be an error code. +* +* bits are first added to a local register. +* Local register is size_t, hence 64-bits on 64-bits systems, or 32-bits on 32-bits systems. +* Writing data into memory is an explicit operation, performed by the flushBits function. +* Hence keep track how many bits are potentially stored into local register to avoid register overflow. +* After a flushBits, a maximum of 7 bits might still be stored into local register. +* +* Avoid storing elements of more than 24 bits if you want compatibility with 32-bits bitstream readers. +* +* Last operation is to close the bitStream. +* The function returns the final size of CStream in bytes. +* If data couldn't fit into `dstBuffer`, it will return a 0 ( == not storable) +*/ + +/*-******************************************** +* bitStream decoding API (read backward) +**********************************************/ +typedef struct { + size_t bitContainer; + unsigned bitsConsumed; + const char *ptr; + const char *start; +} BIT_DStream_t; + +typedef enum { + BIT_DStream_unfinished = 0, + BIT_DStream_endOfBuffer = 1, + BIT_DStream_completed = 2, + BIT_DStream_overflow = 3 +} BIT_DStream_status; /* result of BIT_reloadDStream() */ +/* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... :( */ + +ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize); +ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, unsigned nbBits); +ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD); +ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *bitD); + +/* Start by invoking BIT_initDStream(). +* A chunk of the bitStream is then stored into a local register. +* Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t). +* You can then retrieve bitFields stored into the local register, **in reverse order**. +* Local register is explicitly reloaded from memory by the BIT_reloadDStream() method. +* A reload guarantee a minimum of ((8*sizeof(bitD->bitContainer))-7) bits when its result is BIT_DStream_unfinished. +* Otherwise, it can be less than that, so proceed accordingly. +* Checking if DStream has reached its end can be performed with BIT_endOfDStream(). +*/ + +/*-**************************************** +* unsafe API +******************************************/ +ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits); +/* faster, but works only if value is "clean", meaning all high bits above nbBits are 0 */ + +ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC); +/* unsafe version; does not check buffer overflow */ + +ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, unsigned nbBits); +/* faster, but works only if nbBits >= 1 */ + +/*-************************************************************** +* Internal functions +****************************************************************/ +ZSTD_STATIC unsigned BIT_highbit32(register U32 val) { return 31 - __builtin_clz(val); } + +/*===== Local Constants =====*/ +static const unsigned BIT_mask[] = {0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, + 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, + 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF, 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF}; /* up to 26 bits */ + +/*-************************************************************** +* bitStream encoding +****************************************************************/ +/*! BIT_initCStream() : + * `dstCapacity` must be > sizeof(void*) + * @return : 0 if success, + otherwise an error code (can be tested using ERR_isError() ) */ +ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *startPtr, size_t dstCapacity) +{ + bitC->bitContainer = 0; + bitC->bitPos = 0; + bitC->startPtr = (char *)startPtr; + bitC->ptr = bitC->startPtr; + bitC->endPtr = bitC->startPtr + dstCapacity - sizeof(bitC->ptr); + if (dstCapacity <= sizeof(bitC->ptr)) + return ERROR(dstSize_tooSmall); + return 0; +} + +/*! BIT_addBits() : + can add up to 26 bits into `bitC`. + Does not check for register overflow ! */ +ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits) +{ + bitC->bitContainer |= (value & BIT_mask[nbBits]) << bitC->bitPos; + bitC->bitPos += nbBits; +} + +/*! BIT_addBitsFast() : + * works only if `value` is _clean_, meaning all high bits above nbBits are 0 */ +ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits) +{ + bitC->bitContainer |= value << bitC->bitPos; + bitC->bitPos += nbBits; +} + +/*! BIT_flushBitsFast() : + * unsafe version; does not check buffer overflow */ +ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC) +{ + size_t const nbBytes = bitC->bitPos >> 3; + ZSTD_writeLEST(bitC->ptr, bitC->bitContainer); + bitC->ptr += nbBytes; + bitC->bitPos &= 7; + bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */ +} + +/*! BIT_flushBits() : + * safe version; check for buffer overflow, and prevents it. + * note : does not signal buffer overflow. This will be revealed later on using BIT_closeCStream() */ +ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC) +{ + size_t const nbBytes = bitC->bitPos >> 3; + ZSTD_writeLEST(bitC->ptr, bitC->bitContainer); + bitC->ptr += nbBytes; + if (bitC->ptr > bitC->endPtr) + bitC->ptr = bitC->endPtr; + bitC->bitPos &= 7; + bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */ +} + +/*! BIT_closeCStream() : + * @return : size of CStream, in bytes, + or 0 if it could not fit into dstBuffer */ +ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC) +{ + BIT_addBitsFast(bitC, 1, 1); /* endMark */ + BIT_flushBits(bitC); + + if (bitC->ptr >= bitC->endPtr) + return 0; /* doesn't fit within authorized budget : cancel */ + + return (bitC->ptr - bitC->startPtr) + (bitC->bitPos > 0); +} + +/*-******************************************************** +* bitStream decoding +**********************************************************/ +/*! BIT_initDStream() : +* Initialize a BIT_DStream_t. +* `bitD` : a pointer to an already allocated BIT_DStream_t structure. +* `srcSize` must be the *exact* size of the bitStream, in bytes. +* @return : size of stream (== srcSize) or an errorCode if a problem is detected +*/ +ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize) +{ + if (srcSize < 1) { + memset(bitD, 0, sizeof(*bitD)); + return ERROR(srcSize_wrong); + } + + if (srcSize >= sizeof(bitD->bitContainer)) { /* normal case */ + bitD->start = (const char *)srcBuffer; + bitD->ptr = (const char *)srcBuffer + srcSize - sizeof(bitD->bitContainer); + bitD->bitContainer = ZSTD_readLEST(bitD->ptr); + { + BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1]; + bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0; /* ensures bitsConsumed is always set */ + if (lastByte == 0) + return ERROR(GENERIC); /* endMark not present */ + } + } else { + bitD->start = (const char *)srcBuffer; + bitD->ptr = bitD->start; + bitD->bitContainer = *(const BYTE *)(bitD->start); + switch (srcSize) { + case 7: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[6]) << (sizeof(bitD->bitContainer) * 8 - 16); + case 6: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[5]) << (sizeof(bitD->bitContainer) * 8 - 24); + case 5: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[4]) << (sizeof(bitD->bitContainer) * 8 - 32); + case 4: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[3]) << 24; + case 3: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[2]) << 16; + case 2: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[1]) << 8; + default:; + } + { + BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1]; + bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0; + if (lastByte == 0) + return ERROR(GENERIC); /* endMark not present */ + } + bitD->bitsConsumed += (U32)(sizeof(bitD->bitContainer) - srcSize) * 8; + } + + return srcSize; +} + +ZSTD_STATIC size_t BIT_getUpperBits(size_t bitContainer, U32 const start) { return bitContainer >> start; } + +ZSTD_STATIC size_t BIT_getMiddleBits(size_t bitContainer, U32 const start, U32 const nbBits) { return (bitContainer >> start) & BIT_mask[nbBits]; } + +ZSTD_STATIC size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits) { return bitContainer & BIT_mask[nbBits]; } + +/*! BIT_lookBits() : + * Provides next n bits from local register. + * local register is not modified. + * On 32-bits, maxNbBits==24. + * On 64-bits, maxNbBits==56. + * @return : value extracted + */ +ZSTD_STATIC size_t BIT_lookBits(const BIT_DStream_t *bitD, U32 nbBits) +{ + U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1; + return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask - nbBits) & bitMask); +} + +/*! BIT_lookBitsFast() : +* unsafe version; only works only if nbBits >= 1 */ +ZSTD_STATIC size_t BIT_lookBitsFast(const BIT_DStream_t *bitD, U32 nbBits) +{ + U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1; + return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask + 1) - nbBits) & bitMask); +} + +ZSTD_STATIC void BIT_skipBits(BIT_DStream_t *bitD, U32 nbBits) { bitD->bitsConsumed += nbBits; } + +/*! BIT_readBits() : + * Read (consume) next n bits from local register and update. + * Pay attention to not read more than nbBits contained into local register. + * @return : extracted value. + */ +ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, U32 nbBits) +{ + size_t const value = BIT_lookBits(bitD, nbBits); + BIT_skipBits(bitD, nbBits); + return value; +} + +/*! BIT_readBitsFast() : +* unsafe version; only works only if nbBits >= 1 */ +ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, U32 nbBits) +{ + size_t const value = BIT_lookBitsFast(bitD, nbBits); + BIT_skipBits(bitD, nbBits); + return value; +} + +/*! BIT_reloadDStream() : +* Refill `bitD` from buffer previously set in BIT_initDStream() . +* This function is safe, it guarantees it will not read beyond src buffer. +* @return : status of `BIT_DStream_t` internal register. + if status == BIT_DStream_unfinished, internal register is filled with >= (sizeof(bitD->bitContainer)*8 - 7) bits */ +ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD) +{ + if (bitD->bitsConsumed > (sizeof(bitD->bitContainer) * 8)) /* should not happen => corruption detected */ + return BIT_DStream_overflow; + + if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) { + bitD->ptr -= bitD->bitsConsumed >> 3; + bitD->bitsConsumed &= 7; + bitD->bitContainer = ZSTD_readLEST(bitD->ptr); + return BIT_DStream_unfinished; + } + if (bitD->ptr == bitD->start) { + if (bitD->bitsConsumed < sizeof(bitD->bitContainer) * 8) + return BIT_DStream_endOfBuffer; + return BIT_DStream_completed; + } + { + U32 nbBytes = bitD->bitsConsumed >> 3; + BIT_DStream_status result = BIT_DStream_unfinished; + if (bitD->ptr - nbBytes < bitD->start) { + nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */ + result = BIT_DStream_endOfBuffer; + } + bitD->ptr -= nbBytes; + bitD->bitsConsumed -= nbBytes * 8; + bitD->bitContainer = ZSTD_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */ + return result; + } +} + +/*! BIT_endOfDStream() : +* @return Tells if DStream has exactly reached its end (all bits consumed). +*/ +ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *DStream) +{ + return ((DStream->ptr == DStream->start) && (DStream->bitsConsumed == sizeof(DStream->bitContainer) * 8)); +} + +#endif /* BITSTREAM_H_MODULE */ diff --git a/lib/zstd/compress.c b/lib/zstd/compress.c new file mode 100644 index 000000000000..f9166cf4f7a9 --- /dev/null +++ b/lib/zstd/compress.c @@ -0,0 +1,3484 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/*-************************************* +* Dependencies +***************************************/ +#include "fse.h" +#include "huf.h" +#include "mem.h" +#include "zstd_internal.h" /* includes zstd.h */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/string.h> /* memset */ + +/*-************************************* +* Constants +***************************************/ +static const U32 g_searchStrength = 8; /* control skip over incompressible data */ +#define HASH_READ_SIZE 8 +typedef enum { ZSTDcs_created = 0, ZSTDcs_init, ZSTDcs_ongoing, ZSTDcs_ending } ZSTD_compressionStage_e; + +/*-************************************* +* Helper functions +***************************************/ +size_t ZSTD_compressBound(size_t srcSize) { return FSE_compressBound(srcSize) + 12; } + +/*-************************************* +* Sequence storage +***************************************/ +static void ZSTD_resetSeqStore(seqStore_t *ssPtr) +{ + ssPtr->lit = ssPtr->litStart; + ssPtr->sequences = ssPtr->sequencesStart; + ssPtr->longLengthID = 0; +} + +/*-************************************* +* Context memory management +***************************************/ +struct ZSTD_CCtx_s { + const BYTE *nextSrc; /* next block here to continue on curr prefix */ + const BYTE *base; /* All regular indexes relative to this position */ + const BYTE *dictBase; /* extDict indexes relative to this position */ + U32 dictLimit; /* below that point, need extDict */ + U32 lowLimit; /* below that point, no more data */ + U32 nextToUpdate; /* index from which to continue dictionary update */ + U32 nextToUpdate3; /* index from which to continue dictionary update */ + U32 hashLog3; /* dispatch table : larger == faster, more memory */ + U32 loadedDictEnd; /* index of end of dictionary */ + U32 forceWindow; /* force back-references to respect limit of 1<<wLog, even for dictionary */ + U32 forceRawDict; /* Force loading dictionary in "content-only" mode (no header analysis) */ + ZSTD_compressionStage_e stage; + U32 rep[ZSTD_REP_NUM]; + U32 repToConfirm[ZSTD_REP_NUM]; + U32 dictID; + ZSTD_parameters params; + void *workSpace; + size_t workSpaceSize; + size_t blockSize; + U64 frameContentSize; + struct xxh64_state xxhState; + ZSTD_customMem customMem; + + seqStore_t seqStore; /* sequences storage ptrs */ + U32 *hashTable; + U32 *hashTable3; + U32 *chainTable; + HUF_CElt *hufTable; + U32 flagStaticTables; + HUF_repeat flagStaticHufTable; + FSE_CTable offcodeCTable[FSE_CTABLE_SIZE_U32(OffFSELog, MaxOff)]; + FSE_CTable matchlengthCTable[FSE_CTABLE_SIZE_U32(MLFSELog, MaxML)]; + FSE_CTable litlengthCTable[FSE_CTABLE_SIZE_U32(LLFSELog, MaxLL)]; + unsigned tmpCounters[HUF_COMPRESS_WORKSPACE_SIZE_U32]; +}; + +size_t ZSTD_CCtxWorkspaceBound(ZSTD_compressionParameters cParams) +{ + size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << cParams.windowLog); + U32 const divider = (cParams.searchLength == 3) ? 3 : 4; + size_t const maxNbSeq = blockSize / divider; + size_t const tokenSpace = blockSize + 11 * maxNbSeq; + size_t const chainSize = (cParams.strategy == ZSTD_fast) ? 0 : (1 << cParams.chainLog); + size_t const hSize = ((size_t)1) << cParams.hashLog; + U32 const hashLog3 = (cParams.searchLength > 3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, cParams.windowLog); + size_t const h3Size = ((size_t)1) << hashLog3; + size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32); + size_t const optSpace = + ((MaxML + 1) + (MaxLL + 1) + (MaxOff + 1) + (1 << Litbits)) * sizeof(U32) + (ZSTD_OPT_NUM + 1) * (sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t)); + size_t const workspaceSize = tableSpace + (256 * sizeof(U32)) /* huffTable */ + tokenSpace + + (((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btopt2)) ? optSpace : 0); + + return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_CCtx)) + ZSTD_ALIGN(workspaceSize); +} + +static ZSTD_CCtx *ZSTD_createCCtx_advanced(ZSTD_customMem customMem) +{ + ZSTD_CCtx *cctx; + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + cctx = (ZSTD_CCtx *)ZSTD_malloc(sizeof(ZSTD_CCtx), customMem); + if (!cctx) + return NULL; + memset(cctx, 0, sizeof(ZSTD_CCtx)); + cctx->customMem = customMem; + return cctx; +} + +ZSTD_CCtx *ZSTD_initCCtx(void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + ZSTD_CCtx *cctx = ZSTD_createCCtx_advanced(stackMem); + if (cctx) { + cctx->workSpace = ZSTD_stackAllocAll(cctx->customMem.opaque, &cctx->workSpaceSize); + } + return cctx; +} + +size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx) +{ + if (cctx == NULL) + return 0; /* support free on NULL */ + ZSTD_free(cctx->workSpace, cctx->customMem); + ZSTD_free(cctx, cctx->customMem); + return 0; /* reserved as a potential error code in the future */ +} + +const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx) /* hidden interface */ { return &(ctx->seqStore); } + +static ZSTD_parameters ZSTD_getParamsFromCCtx(const ZSTD_CCtx *cctx) { return cctx->params; } + +/** ZSTD_checkParams() : + ensure param values remain within authorized range. + @return : 0, or an error code if one value is beyond authorized range */ +size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams) +{ +#define CLAMPCHECK(val, min, max) \ + { \ + if ((val < min) | (val > max)) \ + return ERROR(compressionParameter_unsupported); \ + } + CLAMPCHECK(cParams.windowLog, ZSTD_WINDOWLOG_MIN, ZSTD_WINDOWLOG_MAX); + CLAMPCHECK(cParams.chainLog, ZSTD_CHAINLOG_MIN, ZSTD_CHAINLOG_MAX); + CLAMPCHECK(cParams.hashLog, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX); + CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX); + CLAMPCHECK(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX); + CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX); + if ((U32)(cParams.strategy) > (U32)ZSTD_btopt2) + return ERROR(compressionParameter_unsupported); + return 0; +} + +/** ZSTD_cycleLog() : + * condition for correct operation : hashLog > 1 */ +static U32 ZSTD_cycleLog(U32 hashLog, ZSTD_strategy strat) +{ + U32 const btScale = ((U32)strat >= (U32)ZSTD_btlazy2); + return hashLog - btScale; +} + +/** ZSTD_adjustCParams() : + optimize `cPar` for a given input (`srcSize` and `dictSize`). + mostly downsizing to reduce memory consumption and initialization. + Both `srcSize` and `dictSize` are optional (use 0 if unknown), + but if both are 0, no optimization can be done. + Note : cPar is considered validated at this stage. Use ZSTD_checkParams() to ensure that. */ +ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize) +{ + if (srcSize + dictSize == 0) + return cPar; /* no size information available : no adjustment */ + + /* resize params, to use less memory when necessary */ + { + U32 const minSrcSize = (srcSize == 0) ? 500 : 0; + U64 const rSize = srcSize + dictSize + minSrcSize; + if (rSize < ((U64)1 << ZSTD_WINDOWLOG_MAX)) { + U32 const srcLog = MAX(ZSTD_HASHLOG_MIN, ZSTD_highbit32((U32)(rSize)-1) + 1); + if (cPar.windowLog > srcLog) + cPar.windowLog = srcLog; + } + } + if (cPar.hashLog > cPar.windowLog) + cPar.hashLog = cPar.windowLog; + { + U32 const cycleLog = ZSTD_cycleLog(cPar.chainLog, cPar.strategy); + if (cycleLog > cPar.windowLog) + cPar.chainLog -= (cycleLog - cPar.windowLog); + } + + if (cPar.windowLog < ZSTD_WINDOWLOG_ABSOLUTEMIN) + cPar.windowLog = ZSTD_WINDOWLOG_ABSOLUTEMIN; /* required for frame header */ + + return cPar; +} + +static U32 ZSTD_equivalentParams(ZSTD_parameters param1, ZSTD_parameters param2) +{ + return (param1.cParams.hashLog == param2.cParams.hashLog) & (param1.cParams.chainLog == param2.cParams.chainLog) & + (param1.cParams.strategy == param2.cParams.strategy) & ((param1.cParams.searchLength == 3) == (param2.cParams.searchLength == 3)); +} + +/*! ZSTD_continueCCtx() : + reuse CCtx without reset (note : requires no dictionary) */ +static size_t ZSTD_continueCCtx(ZSTD_CCtx *cctx, ZSTD_parameters params, U64 frameContentSize) +{ + U32 const end = (U32)(cctx->nextSrc - cctx->base); + cctx->params = params; + cctx->frameContentSize = frameContentSize; + cctx->lowLimit = end; + cctx->dictLimit = end; + cctx->nextToUpdate = end + 1; + cctx->stage = ZSTDcs_init; + cctx->dictID = 0; + cctx->loadedDictEnd = 0; + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + cctx->rep[i] = repStartValue[i]; + } + cctx->seqStore.litLengthSum = 0; /* force reset of btopt stats */ + xxh64_reset(&cctx->xxhState, 0); + return 0; +} + +typedef enum { ZSTDcrp_continue, ZSTDcrp_noMemset, ZSTDcrp_fullReset } ZSTD_compResetPolicy_e; + +/*! ZSTD_resetCCtx_advanced() : + note : `params` must be validated */ +static size_t ZSTD_resetCCtx_advanced(ZSTD_CCtx *zc, ZSTD_parameters params, U64 frameContentSize, ZSTD_compResetPolicy_e const crp) +{ + if (crp == ZSTDcrp_continue) + if (ZSTD_equivalentParams(params, zc->params)) { + zc->flagStaticTables = 0; + zc->flagStaticHufTable = HUF_repeat_none; + return ZSTD_continueCCtx(zc, params, frameContentSize); + } + + { + size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << params.cParams.windowLog); + U32 const divider = (params.cParams.searchLength == 3) ? 3 : 4; + size_t const maxNbSeq = blockSize / divider; + size_t const tokenSpace = blockSize + 11 * maxNbSeq; + size_t const chainSize = (params.cParams.strategy == ZSTD_fast) ? 0 : (1 << params.cParams.chainLog); + size_t const hSize = ((size_t)1) << params.cParams.hashLog; + U32 const hashLog3 = (params.cParams.searchLength > 3) ? 0 : MIN(ZSTD_HASHLOG3_MAX, params.cParams.windowLog); + size_t const h3Size = ((size_t)1) << hashLog3; + size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32); + void *ptr; + + /* Check if workSpace is large enough, alloc a new one if needed */ + { + size_t const optSpace = ((MaxML + 1) + (MaxLL + 1) + (MaxOff + 1) + (1 << Litbits)) * sizeof(U32) + + (ZSTD_OPT_NUM + 1) * (sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t)); + size_t const neededSpace = tableSpace + (256 * sizeof(U32)) /* huffTable */ + tokenSpace + + (((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) ? optSpace : 0); + if (zc->workSpaceSize < neededSpace) { + ZSTD_free(zc->workSpace, zc->customMem); + zc->workSpace = ZSTD_malloc(neededSpace, zc->customMem); + if (zc->workSpace == NULL) + return ERROR(memory_allocation); + zc->workSpaceSize = neededSpace; + } + } + + if (crp != ZSTDcrp_noMemset) + memset(zc->workSpace, 0, tableSpace); /* reset tables only */ + xxh64_reset(&zc->xxhState, 0); + zc->hashLog3 = hashLog3; + zc->hashTable = (U32 *)(zc->workSpace); + zc->chainTable = zc->hashTable + hSize; + zc->hashTable3 = zc->chainTable + chainSize; + ptr = zc->hashTable3 + h3Size; + zc->hufTable = (HUF_CElt *)ptr; + zc->flagStaticTables = 0; + zc->flagStaticHufTable = HUF_repeat_none; + ptr = ((U32 *)ptr) + 256; /* note : HUF_CElt* is incomplete type, size is simulated using U32 */ + + zc->nextToUpdate = 1; + zc->nextSrc = NULL; + zc->base = NULL; + zc->dictBase = NULL; + zc->dictLimit = 0; + zc->lowLimit = 0; + zc->params = params; + zc->blockSize = blockSize; + zc->frameContentSize = frameContentSize; + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + zc->rep[i] = repStartValue[i]; + } + + if ((params.cParams.strategy == ZSTD_btopt) || (params.cParams.strategy == ZSTD_btopt2)) { + zc->seqStore.litFreq = (U32 *)ptr; + zc->seqStore.litLengthFreq = zc->seqStore.litFreq + (1 << Litbits); + zc->seqStore.matchLengthFreq = zc->seqStore.litLengthFreq + (MaxLL + 1); + zc->seqStore.offCodeFreq = zc->seqStore.matchLengthFreq + (MaxML + 1); + ptr = zc->seqStore.offCodeFreq + (MaxOff + 1); + zc->seqStore.matchTable = (ZSTD_match_t *)ptr; + ptr = zc->seqStore.matchTable + ZSTD_OPT_NUM + 1; + zc->seqStore.priceTable = (ZSTD_optimal_t *)ptr; + ptr = zc->seqStore.priceTable + ZSTD_OPT_NUM + 1; + zc->seqStore.litLengthSum = 0; + } + zc->seqStore.sequencesStart = (seqDef *)ptr; + ptr = zc->seqStore.sequencesStart + maxNbSeq; + zc->seqStore.llCode = (BYTE *)ptr; + zc->seqStore.mlCode = zc->seqStore.llCode + maxNbSeq; + zc->seqStore.ofCode = zc->seqStore.mlCode + maxNbSeq; + zc->seqStore.litStart = zc->seqStore.ofCode + maxNbSeq; + + zc->stage = ZSTDcs_init; + zc->dictID = 0; + zc->loadedDictEnd = 0; + + return 0; + } +} + +/* ZSTD_invalidateRepCodes() : + * ensures next compression will not use repcodes from previous block. + * Note : only works with regular variant; + * do not use with extDict variant ! */ +void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx) +{ + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + cctx->rep[i] = 0; +} + +/*! ZSTD_copyCCtx() : +* Duplicate an existing context `srcCCtx` into another one `dstCCtx`. +* Only works during stage ZSTDcs_init (i.e. after creation, but before first call to ZSTD_compressContinue()). +* @return : 0, or an error code */ +size_t ZSTD_copyCCtx(ZSTD_CCtx *dstCCtx, const ZSTD_CCtx *srcCCtx, unsigned long long pledgedSrcSize) +{ + if (srcCCtx->stage != ZSTDcs_init) + return ERROR(stage_wrong); + + memcpy(&dstCCtx->customMem, &srcCCtx->customMem, sizeof(ZSTD_customMem)); + { + ZSTD_parameters params = srcCCtx->params; + params.fParams.contentSizeFlag = (pledgedSrcSize > 0); + ZSTD_resetCCtx_advanced(dstCCtx, params, pledgedSrcSize, ZSTDcrp_noMemset); + } + + /* copy tables */ + { + size_t const chainSize = (srcCCtx->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << srcCCtx->params.cParams.chainLog); + size_t const hSize = ((size_t)1) << srcCCtx->params.cParams.hashLog; + size_t const h3Size = (size_t)1 << srcCCtx->hashLog3; + size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32); + memcpy(dstCCtx->workSpace, srcCCtx->workSpace, tableSpace); + } + + /* copy dictionary offsets */ + dstCCtx->nextToUpdate = srcCCtx->nextToUpdate; + dstCCtx->nextToUpdate3 = srcCCtx->nextToUpdate3; + dstCCtx->nextSrc = srcCCtx->nextSrc; + dstCCtx->base = srcCCtx->base; + dstCCtx->dictBase = srcCCtx->dictBase; + dstCCtx->dictLimit = srcCCtx->dictLimit; + dstCCtx->lowLimit = srcCCtx->lowLimit; + dstCCtx->loadedDictEnd = srcCCtx->loadedDictEnd; + dstCCtx->dictID = srcCCtx->dictID; + + /* copy entropy tables */ + dstCCtx->flagStaticTables = srcCCtx->flagStaticTables; + dstCCtx->flagStaticHufTable = srcCCtx->flagStaticHufTable; + if (srcCCtx->flagStaticTables) { + memcpy(dstCCtx->litlengthCTable, srcCCtx->litlengthCTable, sizeof(dstCCtx->litlengthCTable)); + memcpy(dstCCtx->matchlengthCTable, srcCCtx->matchlengthCTable, sizeof(dstCCtx->matchlengthCTable)); + memcpy(dstCCtx->offcodeCTable, srcCCtx->offcodeCTable, sizeof(dstCCtx->offcodeCTable)); + } + if (srcCCtx->flagStaticHufTable) { + memcpy(dstCCtx->hufTable, srcCCtx->hufTable, 256 * 4); + } + + return 0; +} + +/*! ZSTD_reduceTable() : +* reduce table indexes by `reducerValue` */ +static void ZSTD_reduceTable(U32 *const table, U32 const size, U32 const reducerValue) +{ + U32 u; + for (u = 0; u < size; u++) { + if (table[u] < reducerValue) + table[u] = 0; + else + table[u] -= reducerValue; + } +} + +/*! ZSTD_reduceIndex() : +* rescale all indexes to avoid future overflow (indexes are U32) */ +static void ZSTD_reduceIndex(ZSTD_CCtx *zc, const U32 reducerValue) +{ + { + U32 const hSize = 1 << zc->params.cParams.hashLog; + ZSTD_reduceTable(zc->hashTable, hSize, reducerValue); + } + + { + U32 const chainSize = (zc->params.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->params.cParams.chainLog); + ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue); + } + + { + U32 const h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0; + ZSTD_reduceTable(zc->hashTable3, h3Size, reducerValue); + } +} + +/*-******************************************************* +* Block entropic compression +*********************************************************/ + +/* See doc/zstd_compression_format.md for detailed format description */ + +size_t ZSTD_noCompressBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + if (srcSize + ZSTD_blockHeaderSize > dstCapacity) + return ERROR(dstSize_tooSmall); + memcpy((BYTE *)dst + ZSTD_blockHeaderSize, src, srcSize); + ZSTD_writeLE24(dst, (U32)(srcSize << 2) + (U32)bt_raw); + return ZSTD_blockHeaderSize + srcSize; +} + +static size_t ZSTD_noCompressLiterals(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + BYTE *const ostart = (BYTE * const)dst; + U32 const flSize = 1 + (srcSize > 31) + (srcSize > 4095); + + if (srcSize + flSize > dstCapacity) + return ERROR(dstSize_tooSmall); + + switch (flSize) { + case 1: /* 2 - 1 - 5 */ ostart[0] = (BYTE)((U32)set_basic + (srcSize << 3)); break; + case 2: /* 2 - 2 - 12 */ ZSTD_writeLE16(ostart, (U16)((U32)set_basic + (1 << 2) + (srcSize << 4))); break; + default: /*note : should not be necessary : flSize is within {1,2,3} */ + case 3: /* 2 - 2 - 20 */ ZSTD_writeLE32(ostart, (U32)((U32)set_basic + (3 << 2) + (srcSize << 4))); break; + } + + memcpy(ostart + flSize, src, srcSize); + return srcSize + flSize; +} + +static size_t ZSTD_compressRleLiteralsBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + BYTE *const ostart = (BYTE * const)dst; + U32 const flSize = 1 + (srcSize > 31) + (srcSize > 4095); + + (void)dstCapacity; /* dstCapacity already guaranteed to be >=4, hence large enough */ + + switch (flSize) { + case 1: /* 2 - 1 - 5 */ ostart[0] = (BYTE)((U32)set_rle + (srcSize << 3)); break; + case 2: /* 2 - 2 - 12 */ ZSTD_writeLE16(ostart, (U16)((U32)set_rle + (1 << 2) + (srcSize << 4))); break; + default: /*note : should not be necessary : flSize is necessarily within {1,2,3} */ + case 3: /* 2 - 2 - 20 */ ZSTD_writeLE32(ostart, (U32)((U32)set_rle + (3 << 2) + (srcSize << 4))); break; + } + + ostart[flSize] = *(const BYTE *)src; + return flSize + 1; +} + +static size_t ZSTD_minGain(size_t srcSize) { return (srcSize >> 6) + 2; } + +static size_t ZSTD_compressLiterals(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t const minGain = ZSTD_minGain(srcSize); + size_t const lhSize = 3 + (srcSize >= 1 KB) + (srcSize >= 16 KB); + BYTE *const ostart = (BYTE *)dst; + U32 singleStream = srcSize < 256; + symbolEncodingType_e hType = set_compressed; + size_t cLitSize; + +/* small ? don't even attempt compression (speed opt) */ +#define LITERAL_NOENTROPY 63 + { + size_t const minLitSize = zc->flagStaticHufTable == HUF_repeat_valid ? 6 : LITERAL_NOENTROPY; + if (srcSize <= minLitSize) + return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize); + } + + if (dstCapacity < lhSize + 1) + return ERROR(dstSize_tooSmall); /* not enough space for compression */ + { + HUF_repeat repeat = zc->flagStaticHufTable; + int const preferRepeat = zc->params.cParams.strategy < ZSTD_lazy ? srcSize <= 1024 : 0; + if (repeat == HUF_repeat_valid && lhSize == 3) + singleStream = 1; + cLitSize = singleStream ? HUF_compress1X_repeat(ostart + lhSize, dstCapacity - lhSize, src, srcSize, 255, 11, zc->tmpCounters, + sizeof(zc->tmpCounters), zc->hufTable, &repeat, preferRepeat) + : HUF_compress4X_repeat(ostart + lhSize, dstCapacity - lhSize, src, srcSize, 255, 11, zc->tmpCounters, + sizeof(zc->tmpCounters), zc->hufTable, &repeat, preferRepeat); + if (repeat != HUF_repeat_none) { + hType = set_repeat; + } /* reused the existing table */ + else { + zc->flagStaticHufTable = HUF_repeat_check; + } /* now have a table to reuse */ + } + + if ((cLitSize == 0) | (cLitSize >= srcSize - minGain)) { + zc->flagStaticHufTable = HUF_repeat_none; + return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize); + } + if (cLitSize == 1) { + zc->flagStaticHufTable = HUF_repeat_none; + return ZSTD_compressRleLiteralsBlock(dst, dstCapacity, src, srcSize); + } + + /* Build header */ + switch (lhSize) { + case 3: /* 2 - 2 - 10 - 10 */ + { + U32 const lhc = hType + ((!singleStream) << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 14); + ZSTD_writeLE24(ostart, lhc); + break; + } + case 4: /* 2 - 2 - 14 - 14 */ + { + U32 const lhc = hType + (2 << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 18); + ZSTD_writeLE32(ostart, lhc); + break; + } + default: /* should not be necessary, lhSize is only {3,4,5} */ + case 5: /* 2 - 2 - 18 - 18 */ + { + U32 const lhc = hType + (3 << 2) + ((U32)srcSize << 4) + ((U32)cLitSize << 22); + ZSTD_writeLE32(ostart, lhc); + ostart[4] = (BYTE)(cLitSize >> 10); + break; + } + } + return lhSize + cLitSize; +} + +static const BYTE LL_Code[64] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 16, 17, 17, 18, 18, + 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, + 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24}; + +static const BYTE ML_Code[128] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, + 26, 27, 28, 29, 30, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 36, 36, 36, 37, 37, 37, 37, 38, 38, 38, 38, + 38, 38, 38, 38, 39, 39, 39, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, + 40, 40, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 42, 42, 42, 42, 42, 42, 42, 42, + 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42}; + +void ZSTD_seqToCodes(const seqStore_t *seqStorePtr) +{ + BYTE const LL_deltaCode = 19; + BYTE const ML_deltaCode = 36; + const seqDef *const sequences = seqStorePtr->sequencesStart; + BYTE *const llCodeTable = seqStorePtr->llCode; + BYTE *const ofCodeTable = seqStorePtr->ofCode; + BYTE *const mlCodeTable = seqStorePtr->mlCode; + U32 const nbSeq = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart); + U32 u; + for (u = 0; u < nbSeq; u++) { + U32 const llv = sequences[u].litLength; + U32 const mlv = sequences[u].matchLength; + llCodeTable[u] = (llv > 63) ? (BYTE)ZSTD_highbit32(llv) + LL_deltaCode : LL_Code[llv]; + ofCodeTable[u] = (BYTE)ZSTD_highbit32(sequences[u].offset); + mlCodeTable[u] = (mlv > 127) ? (BYTE)ZSTD_highbit32(mlv) + ML_deltaCode : ML_Code[mlv]; + } + if (seqStorePtr->longLengthID == 1) + llCodeTable[seqStorePtr->longLengthPos] = MaxLL; + if (seqStorePtr->longLengthID == 2) + mlCodeTable[seqStorePtr->longLengthPos] = MaxML; +} + +ZSTD_STATIC size_t ZSTD_compressSequences_internal(ZSTD_CCtx *zc, void *dst, size_t dstCapacity) +{ + const int longOffsets = zc->params.cParams.windowLog > STREAM_ACCUMULATOR_MIN; + const seqStore_t *seqStorePtr = &(zc->seqStore); + FSE_CTable *CTable_LitLength = zc->litlengthCTable; + FSE_CTable *CTable_OffsetBits = zc->offcodeCTable; + FSE_CTable *CTable_MatchLength = zc->matchlengthCTable; + U32 LLtype, Offtype, MLtype; /* compressed, raw or rle */ + const seqDef *const sequences = seqStorePtr->sequencesStart; + const BYTE *const ofCodeTable = seqStorePtr->ofCode; + const BYTE *const llCodeTable = seqStorePtr->llCode; + const BYTE *const mlCodeTable = seqStorePtr->mlCode; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstCapacity; + BYTE *op = ostart; + size_t const nbSeq = seqStorePtr->sequences - seqStorePtr->sequencesStart; + BYTE *seqHead; + + U32 *count; + S16 *norm; + U32 *workspace; + size_t workspaceSize = sizeof(zc->tmpCounters); + { + size_t spaceUsed32 = 0; + count = (U32 *)zc->tmpCounters + spaceUsed32; + spaceUsed32 += MaxSeq + 1; + norm = (S16 *)((U32 *)zc->tmpCounters + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(S16) * (MaxSeq + 1), sizeof(U32)) >> 2; + + workspace = (U32 *)zc->tmpCounters + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + } + + /* Compress literals */ + { + const BYTE *const literals = seqStorePtr->litStart; + size_t const litSize = seqStorePtr->lit - literals; + size_t const cSize = ZSTD_compressLiterals(zc, op, dstCapacity, literals, litSize); + if (ZSTD_isError(cSize)) + return cSize; + op += cSize; + } + + /* Sequences Header */ + if ((oend - op) < 3 /*max nbSeq Size*/ + 1 /*seqHead */) + return ERROR(dstSize_tooSmall); + if (nbSeq < 0x7F) + *op++ = (BYTE)nbSeq; + else if (nbSeq < LONGNBSEQ) + op[0] = (BYTE)((nbSeq >> 8) + 0x80), op[1] = (BYTE)nbSeq, op += 2; + else + op[0] = 0xFF, ZSTD_writeLE16(op + 1, (U16)(nbSeq - LONGNBSEQ)), op += 3; + if (nbSeq == 0) + return op - ostart; + + /* seqHead : flags for FSE encoding type */ + seqHead = op++; + +#define MIN_SEQ_FOR_DYNAMIC_FSE 64 +#define MAX_SEQ_FOR_STATIC_FSE 1000 + + /* convert length/distances into codes */ + ZSTD_seqToCodes(seqStorePtr); + + /* CTable for Literal Lengths */ + { + U32 max = MaxLL; + size_t const mostFrequent = FSE_countFast_wksp(count, &max, llCodeTable, nbSeq, workspace); + if ((mostFrequent == nbSeq) && (nbSeq > 2)) { + *op++ = llCodeTable[0]; + FSE_buildCTable_rle(CTable_LitLength, (BYTE)max); + LLtype = set_rle; + } else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) { + LLtype = set_repeat; + } else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (LL_defaultNormLog - 1)))) { + FSE_buildCTable_wksp(CTable_LitLength, LL_defaultNorm, MaxLL, LL_defaultNormLog, workspace, workspaceSize); + LLtype = set_basic; + } else { + size_t nbSeq_1 = nbSeq; + const U32 tableLog = FSE_optimalTableLog(LLFSELog, nbSeq, max); + if (count[llCodeTable[nbSeq - 1]] > 1) { + count[llCodeTable[nbSeq - 1]]--; + nbSeq_1--; + } + FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max); + { + size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */ + if (FSE_isError(NCountSize)) + return NCountSize; + op += NCountSize; + } + FSE_buildCTable_wksp(CTable_LitLength, norm, max, tableLog, workspace, workspaceSize); + LLtype = set_compressed; + } + } + + /* CTable for Offsets */ + { + U32 max = MaxOff; + size_t const mostFrequent = FSE_countFast_wksp(count, &max, ofCodeTable, nbSeq, workspace); + if ((mostFrequent == nbSeq) && (nbSeq > 2)) { + *op++ = ofCodeTable[0]; + FSE_buildCTable_rle(CTable_OffsetBits, (BYTE)max); + Offtype = set_rle; + } else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) { + Offtype = set_repeat; + } else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (OF_defaultNormLog - 1)))) { + FSE_buildCTable_wksp(CTable_OffsetBits, OF_defaultNorm, MaxOff, OF_defaultNormLog, workspace, workspaceSize); + Offtype = set_basic; + } else { + size_t nbSeq_1 = nbSeq; + const U32 tableLog = FSE_optimalTableLog(OffFSELog, nbSeq, max); + if (count[ofCodeTable[nbSeq - 1]] > 1) { + count[ofCodeTable[nbSeq - 1]]--; + nbSeq_1--; + } + FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max); + { + size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */ + if (FSE_isError(NCountSize)) + return NCountSize; + op += NCountSize; + } + FSE_buildCTable_wksp(CTable_OffsetBits, norm, max, tableLog, workspace, workspaceSize); + Offtype = set_compressed; + } + } + + /* CTable for MatchLengths */ + { + U32 max = MaxML; + size_t const mostFrequent = FSE_countFast_wksp(count, &max, mlCodeTable, nbSeq, workspace); + if ((mostFrequent == nbSeq) && (nbSeq > 2)) { + *op++ = *mlCodeTable; + FSE_buildCTable_rle(CTable_MatchLength, (BYTE)max); + MLtype = set_rle; + } else if ((zc->flagStaticTables) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) { + MLtype = set_repeat; + } else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (ML_defaultNormLog - 1)))) { + FSE_buildCTable_wksp(CTable_MatchLength, ML_defaultNorm, MaxML, ML_defaultNormLog, workspace, workspaceSize); + MLtype = set_basic; + } else { + size_t nbSeq_1 = nbSeq; + const U32 tableLog = FSE_optimalTableLog(MLFSELog, nbSeq, max); + if (count[mlCodeTable[nbSeq - 1]] > 1) { + count[mlCodeTable[nbSeq - 1]]--; + nbSeq_1--; + } + FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max); + { + size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */ + if (FSE_isError(NCountSize)) + return NCountSize; + op += NCountSize; + } + FSE_buildCTable_wksp(CTable_MatchLength, norm, max, tableLog, workspace, workspaceSize); + MLtype = set_compressed; + } + } + + *seqHead = (BYTE)((LLtype << 6) + (Offtype << 4) + (MLtype << 2)); + zc->flagStaticTables = 0; + + /* Encoding Sequences */ + { + BIT_CStream_t blockStream; + FSE_CState_t stateMatchLength; + FSE_CState_t stateOffsetBits; + FSE_CState_t stateLitLength; + + CHECK_E(BIT_initCStream(&blockStream, op, oend - op), dstSize_tooSmall); /* not enough space remaining */ + + /* first symbols */ + FSE_initCState2(&stateMatchLength, CTable_MatchLength, mlCodeTable[nbSeq - 1]); + FSE_initCState2(&stateOffsetBits, CTable_OffsetBits, ofCodeTable[nbSeq - 1]); + FSE_initCState2(&stateLitLength, CTable_LitLength, llCodeTable[nbSeq - 1]); + BIT_addBits(&blockStream, sequences[nbSeq - 1].litLength, LL_bits[llCodeTable[nbSeq - 1]]); + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); + BIT_addBits(&blockStream, sequences[nbSeq - 1].matchLength, ML_bits[mlCodeTable[nbSeq - 1]]); + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); + if (longOffsets) { + U32 const ofBits = ofCodeTable[nbSeq - 1]; + int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN - 1); + if (extraBits) { + BIT_addBits(&blockStream, sequences[nbSeq - 1].offset, extraBits); + BIT_flushBits(&blockStream); + } + BIT_addBits(&blockStream, sequences[nbSeq - 1].offset >> extraBits, ofBits - extraBits); + } else { + BIT_addBits(&blockStream, sequences[nbSeq - 1].offset, ofCodeTable[nbSeq - 1]); + } + BIT_flushBits(&blockStream); + + { + size_t n; + for (n = nbSeq - 2; n < nbSeq; n--) { /* intentional underflow */ + BYTE const llCode = llCodeTable[n]; + BYTE const ofCode = ofCodeTable[n]; + BYTE const mlCode = mlCodeTable[n]; + U32 const llBits = LL_bits[llCode]; + U32 const ofBits = ofCode; /* 32b*/ /* 64b*/ + U32 const mlBits = ML_bits[mlCode]; + /* (7)*/ /* (7)*/ + FSE_encodeSymbol(&blockStream, &stateOffsetBits, ofCode); /* 15 */ /* 15 */ + FSE_encodeSymbol(&blockStream, &stateMatchLength, mlCode); /* 24 */ /* 24 */ + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); /* (7)*/ + FSE_encodeSymbol(&blockStream, &stateLitLength, llCode); /* 16 */ /* 33 */ + if (ZSTD_32bits() || (ofBits + mlBits + llBits >= 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) + BIT_flushBits(&blockStream); /* (7)*/ + BIT_addBits(&blockStream, sequences[n].litLength, llBits); + if (ZSTD_32bits() && ((llBits + mlBits) > 24)) + BIT_flushBits(&blockStream); + BIT_addBits(&blockStream, sequences[n].matchLength, mlBits); + if (ZSTD_32bits()) + BIT_flushBits(&blockStream); /* (7)*/ + if (longOffsets) { + int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN - 1); + if (extraBits) { + BIT_addBits(&blockStream, sequences[n].offset, extraBits); + BIT_flushBits(&blockStream); /* (7)*/ + } + BIT_addBits(&blockStream, sequences[n].offset >> extraBits, ofBits - extraBits); /* 31 */ + } else { + BIT_addBits(&blockStream, sequences[n].offset, ofBits); /* 31 */ + } + BIT_flushBits(&blockStream); /* (7)*/ + } + } + + FSE_flushCState(&blockStream, &stateMatchLength); + FSE_flushCState(&blockStream, &stateOffsetBits); + FSE_flushCState(&blockStream, &stateLitLength); + + { + size_t const streamSize = BIT_closeCStream(&blockStream); + if (streamSize == 0) + return ERROR(dstSize_tooSmall); /* not enough space */ + op += streamSize; + } + } + return op - ostart; +} + +ZSTD_STATIC size_t ZSTD_compressSequences(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, size_t srcSize) +{ + size_t const cSize = ZSTD_compressSequences_internal(zc, dst, dstCapacity); + size_t const minGain = ZSTD_minGain(srcSize); + size_t const maxCSize = srcSize - minGain; + /* If the srcSize <= dstCapacity, then there is enough space to write a + * raw uncompressed block. Since we ran out of space, the block must not + * be compressible, so fall back to a raw uncompressed block. + */ + int const uncompressibleError = cSize == ERROR(dstSize_tooSmall) && srcSize <= dstCapacity; + int i; + + if (ZSTD_isError(cSize) && !uncompressibleError) + return cSize; + if (cSize >= maxCSize || uncompressibleError) { + zc->flagStaticHufTable = HUF_repeat_none; + return 0; + } + /* confirm repcodes */ + for (i = 0; i < ZSTD_REP_NUM; i++) + zc->rep[i] = zc->repToConfirm[i]; + return cSize; +} + +/*! ZSTD_storeSeq() : + Store a sequence (literal length, literals, offset code and match length code) into seqStore_t. + `offsetCode` : distance to match, or 0 == repCode. + `matchCode` : matchLength - MINMATCH +*/ +ZSTD_STATIC void ZSTD_storeSeq(seqStore_t *seqStorePtr, size_t litLength, const void *literals, U32 offsetCode, size_t matchCode) +{ + /* copy Literals */ + ZSTD_wildcopy(seqStorePtr->lit, literals, litLength); + seqStorePtr->lit += litLength; + + /* literal Length */ + if (litLength > 0xFFFF) { + seqStorePtr->longLengthID = 1; + seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart); + } + seqStorePtr->sequences[0].litLength = (U16)litLength; + + /* match offset */ + seqStorePtr->sequences[0].offset = offsetCode + 1; + + /* match Length */ + if (matchCode > 0xFFFF) { + seqStorePtr->longLengthID = 2; + seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart); + } + seqStorePtr->sequences[0].matchLength = (U16)matchCode; + + seqStorePtr->sequences++; +} + +/*-************************************* +* Match length counter +***************************************/ +static unsigned ZSTD_NbCommonBytes(register size_t val) +{ + if (ZSTD_isLittleEndian()) { + if (ZSTD_64bits()) { + return (__builtin_ctzll((U64)val) >> 3); + } else { /* 32 bits */ + return (__builtin_ctz((U32)val) >> 3); + } + } else { /* Big Endian CPU */ + if (ZSTD_64bits()) { + return (__builtin_clzll(val) >> 3); + } else { /* 32 bits */ + return (__builtin_clz((U32)val) >> 3); + } + } +} + +static size_t ZSTD_count(const BYTE *pIn, const BYTE *pMatch, const BYTE *const pInLimit) +{ + const BYTE *const pStart = pIn; + const BYTE *const pInLoopLimit = pInLimit - (sizeof(size_t) - 1); + + while (pIn < pInLoopLimit) { + size_t const diff = ZSTD_readST(pMatch) ^ ZSTD_readST(pIn); + if (!diff) { + pIn += sizeof(size_t); + pMatch += sizeof(size_t); + continue; + } + pIn += ZSTD_NbCommonBytes(diff); + return (size_t)(pIn - pStart); + } + if (ZSTD_64bits()) + if ((pIn < (pInLimit - 3)) && (ZSTD_read32(pMatch) == ZSTD_read32(pIn))) { + pIn += 4; + pMatch += 4; + } + if ((pIn < (pInLimit - 1)) && (ZSTD_read16(pMatch) == ZSTD_read16(pIn))) { + pIn += 2; + pMatch += 2; + } + if ((pIn < pInLimit) && (*pMatch == *pIn)) + pIn++; + return (size_t)(pIn - pStart); +} + +/** ZSTD_count_2segments() : +* can count match length with `ip` & `match` in 2 different segments. +* convention : on reaching mEnd, match count continue starting from iStart +*/ +static size_t ZSTD_count_2segments(const BYTE *ip, const BYTE *match, const BYTE *iEnd, const BYTE *mEnd, const BYTE *iStart) +{ + const BYTE *const vEnd = MIN(ip + (mEnd - match), iEnd); + size_t const matchLength = ZSTD_count(ip, match, vEnd); + if (match + matchLength != mEnd) + return matchLength; + return matchLength + ZSTD_count(ip + matchLength, iStart, iEnd); +} + +/*-************************************* +* Hashes +***************************************/ +static const U32 prime3bytes = 506832829U; +static U32 ZSTD_hash3(U32 u, U32 h) { return ((u << (32 - 24)) * prime3bytes) >> (32 - h); } +ZSTD_STATIC size_t ZSTD_hash3Ptr(const void *ptr, U32 h) { return ZSTD_hash3(ZSTD_readLE32(ptr), h); } /* only in zstd_opt.h */ + +static const U32 prime4bytes = 2654435761U; +static U32 ZSTD_hash4(U32 u, U32 h) { return (u * prime4bytes) >> (32 - h); } +static size_t ZSTD_hash4Ptr(const void *ptr, U32 h) { return ZSTD_hash4(ZSTD_read32(ptr), h); } + +static const U64 prime5bytes = 889523592379ULL; +static size_t ZSTD_hash5(U64 u, U32 h) { return (size_t)(((u << (64 - 40)) * prime5bytes) >> (64 - h)); } +static size_t ZSTD_hash5Ptr(const void *p, U32 h) { return ZSTD_hash5(ZSTD_readLE64(p), h); } + +static const U64 prime6bytes = 227718039650203ULL; +static size_t ZSTD_hash6(U64 u, U32 h) { return (size_t)(((u << (64 - 48)) * prime6bytes) >> (64 - h)); } +static size_t ZSTD_hash6Ptr(const void *p, U32 h) { return ZSTD_hash6(ZSTD_readLE64(p), h); } + +static const U64 prime7bytes = 58295818150454627ULL; +static size_t ZSTD_hash7(U64 u, U32 h) { return (size_t)(((u << (64 - 56)) * prime7bytes) >> (64 - h)); } +static size_t ZSTD_hash7Ptr(const void *p, U32 h) { return ZSTD_hash7(ZSTD_readLE64(p), h); } + +static const U64 prime8bytes = 0xCF1BBCDCB7A56463ULL; +static size_t ZSTD_hash8(U64 u, U32 h) { return (size_t)(((u)*prime8bytes) >> (64 - h)); } +static size_t ZSTD_hash8Ptr(const void *p, U32 h) { return ZSTD_hash8(ZSTD_readLE64(p), h); } + +static size_t ZSTD_hashPtr(const void *p, U32 hBits, U32 mls) +{ + switch (mls) { + // case 3: return ZSTD_hash3Ptr(p, hBits); + default: + case 4: return ZSTD_hash4Ptr(p, hBits); + case 5: return ZSTD_hash5Ptr(p, hBits); + case 6: return ZSTD_hash6Ptr(p, hBits); + case 7: return ZSTD_hash7Ptr(p, hBits); + case 8: return ZSTD_hash8Ptr(p, hBits); + } +} + +/*-************************************* +* Fast Scan +***************************************/ +static void ZSTD_fillHashTable(ZSTD_CCtx *zc, const void *end, const U32 mls) +{ + U32 *const hashTable = zc->hashTable; + U32 const hBits = zc->params.cParams.hashLog; + const BYTE *const base = zc->base; + const BYTE *ip = base + zc->nextToUpdate; + const BYTE *const iend = ((const BYTE *)end) - HASH_READ_SIZE; + const size_t fastHashFillStep = 3; + + while (ip <= iend) { + hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip - base); + ip += fastHashFillStep; + } +} + +FORCE_INLINE +void ZSTD_compressBlock_fast_generic(ZSTD_CCtx *cctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *const hashTable = cctx->hashTable; + U32 const hBits = cctx->params.cParams.hashLog; + seqStore_t *seqStorePtr = &(cctx->seqStore); + const BYTE *const base = cctx->base; + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const U32 lowestIndex = cctx->dictLimit; + const BYTE *const lowest = base + lowestIndex; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - HASH_READ_SIZE; + U32 offset_1 = cctx->rep[0], offset_2 = cctx->rep[1]; + U32 offsetSaved = 0; + + /* init */ + ip += (ip == lowest); + { + U32 const maxRep = (U32)(ip - lowest); + if (offset_2 > maxRep) + offsetSaved = offset_2, offset_2 = 0; + if (offset_1 > maxRep) + offsetSaved = offset_1, offset_1 = 0; + } + + /* Main Search Loop */ + while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */ + size_t mLength; + size_t const h = ZSTD_hashPtr(ip, hBits, mls); + U32 const curr = (U32)(ip - base); + U32 const matchIndex = hashTable[h]; + const BYTE *match = base + matchIndex; + hashTable[h] = curr; /* update hash table */ + + if ((offset_1 > 0) & (ZSTD_read32(ip + 1 - offset_1) == ZSTD_read32(ip + 1))) { + mLength = ZSTD_count(ip + 1 + 4, ip + 1 + 4 - offset_1, iend) + 4; + ip++; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH); + } else { + U32 offset; + if ((matchIndex <= lowestIndex) || (ZSTD_read32(match) != ZSTD_read32(ip))) { + ip += ((ip - anchor) >> g_searchStrength) + 1; + continue; + } + mLength = ZSTD_count(ip + 4, match + 4, iend) + 4; + offset = (U32)(ip - match); + while (((ip > anchor) & (match > lowest)) && (ip[-1] == match[-1])) { + ip--; + match--; + mLength++; + } /* catch up */ + offset_2 = offset_1; + offset_1 = offset; + + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH); + } + + /* match found */ + ip += mLength; + anchor = ip; + + if (ip <= ilimit) { + /* Fill Table */ + hashTable[ZSTD_hashPtr(base + curr + 2, hBits, mls)] = curr + 2; /* here because curr+2 could be > iend-8 */ + hashTable[ZSTD_hashPtr(ip - 2, hBits, mls)] = (U32)(ip - 2 - base); + /* check immediate repcode */ + while ((ip <= ilimit) && ((offset_2 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) { + /* store sequence */ + size_t const rLength = ZSTD_count(ip + 4, ip + 4 - offset_2, iend) + 4; + { + U32 const tmpOff = offset_2; + offset_2 = offset_1; + offset_1 = tmpOff; + } /* swap offset_2 <=> offset_1 */ + hashTable[ZSTD_hashPtr(ip, hBits, mls)] = (U32)(ip - base); + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength - MINMATCH); + ip += rLength; + anchor = ip; + continue; /* faster when present ... (?) */ + } + } + } + + /* save reps for next block */ + cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved; + cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_fast(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + const U32 mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_fast_generic(ctx, src, srcSize, 7); return; + } +} + +static void ZSTD_compressBlock_fast_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *hashTable = ctx->hashTable; + const U32 hBits = ctx->params.cParams.hashLog; + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const base = ctx->base; + const BYTE *const dictBase = ctx->dictBase; + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const U32 lowestIndex = ctx->lowLimit; + const BYTE *const dictStart = dictBase + lowestIndex; + const U32 dictLimit = ctx->dictLimit; + const BYTE *const lowPrefixPtr = base + dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1]; + + /* Search Loop */ + while (ip < ilimit) { /* < instead of <=, because (ip+1) */ + const size_t h = ZSTD_hashPtr(ip, hBits, mls); + const U32 matchIndex = hashTable[h]; + const BYTE *matchBase = matchIndex < dictLimit ? dictBase : base; + const BYTE *match = matchBase + matchIndex; + const U32 curr = (U32)(ip - base); + const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */ + const BYTE *repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *repMatch = repBase + repIndex; + size_t mLength; + hashTable[h] = curr; /* update hash table */ + + if ((((U32)((dictLimit - 1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex)) && + (ZSTD_read32(repMatch) == ZSTD_read32(ip + 1))) { + const BYTE *repMatchEnd = repIndex < dictLimit ? dictEnd : iend; + mLength = ZSTD_count_2segments(ip + 1 + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repMatchEnd, lowPrefixPtr) + EQUAL_READ32; + ip++; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH); + } else { + if ((matchIndex < lowestIndex) || (ZSTD_read32(match) != ZSTD_read32(ip))) { + ip += ((ip - anchor) >> g_searchStrength) + 1; + continue; + } + { + const BYTE *matchEnd = matchIndex < dictLimit ? dictEnd : iend; + const BYTE *lowMatchPtr = matchIndex < dictLimit ? dictStart : lowPrefixPtr; + U32 offset; + mLength = ZSTD_count_2segments(ip + EQUAL_READ32, match + EQUAL_READ32, iend, matchEnd, lowPrefixPtr) + EQUAL_READ32; + while (((ip > anchor) & (match > lowMatchPtr)) && (ip[-1] == match[-1])) { + ip--; + match--; + mLength++; + } /* catch up */ + offset = curr - matchIndex; + offset_2 = offset_1; + offset_1 = offset; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH); + } + } + + /* found a match : store it */ + ip += mLength; + anchor = ip; + + if (ip <= ilimit) { + /* Fill Table */ + hashTable[ZSTD_hashPtr(base + curr + 2, hBits, mls)] = curr + 2; + hashTable[ZSTD_hashPtr(ip - 2, hBits, mls)] = (U32)(ip - 2 - base); + /* check immediate repcode */ + while (ip <= ilimit) { + U32 const curr2 = (U32)(ip - base); + U32 const repIndex2 = curr2 - offset_2; + const BYTE *repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2; + if ((((U32)((dictLimit - 1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */ + && (ZSTD_read32(repMatch2) == ZSTD_read32(ip))) { + const BYTE *const repEnd2 = repIndex2 < dictLimit ? dictEnd : iend; + size_t repLength2 = + ZSTD_count_2segments(ip + EQUAL_READ32, repMatch2 + EQUAL_READ32, iend, repEnd2, lowPrefixPtr) + EQUAL_READ32; + U32 tmpOffset = offset_2; + offset_2 = offset_1; + offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */ + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, repLength2 - MINMATCH); + hashTable[ZSTD_hashPtr(ip, hBits, mls)] = curr2; + ip += repLength2; + anchor = ip; + continue; + } + break; + } + } + } + + /* save reps for next block */ + ctx->repToConfirm[0] = offset_1; + ctx->repToConfirm[1] = offset_2; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_fast_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + U32 const mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_fast_extDict_generic(ctx, src, srcSize, 7); return; + } +} + +/*-************************************* +* Double Fast +***************************************/ +static void ZSTD_fillDoubleHashTable(ZSTD_CCtx *cctx, const void *end, const U32 mls) +{ + U32 *const hashLarge = cctx->hashTable; + U32 const hBitsL = cctx->params.cParams.hashLog; + U32 *const hashSmall = cctx->chainTable; + U32 const hBitsS = cctx->params.cParams.chainLog; + const BYTE *const base = cctx->base; + const BYTE *ip = base + cctx->nextToUpdate; + const BYTE *const iend = ((const BYTE *)end) - HASH_READ_SIZE; + const size_t fastHashFillStep = 3; + + while (ip <= iend) { + hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip - base); + hashLarge[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip - base); + ip += fastHashFillStep; + } +} + +FORCE_INLINE +void ZSTD_compressBlock_doubleFast_generic(ZSTD_CCtx *cctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *const hashLong = cctx->hashTable; + const U32 hBitsL = cctx->params.cParams.hashLog; + U32 *const hashSmall = cctx->chainTable; + const U32 hBitsS = cctx->params.cParams.chainLog; + seqStore_t *seqStorePtr = &(cctx->seqStore); + const BYTE *const base = cctx->base; + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const U32 lowestIndex = cctx->dictLimit; + const BYTE *const lowest = base + lowestIndex; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - HASH_READ_SIZE; + U32 offset_1 = cctx->rep[0], offset_2 = cctx->rep[1]; + U32 offsetSaved = 0; + + /* init */ + ip += (ip == lowest); + { + U32 const maxRep = (U32)(ip - lowest); + if (offset_2 > maxRep) + offsetSaved = offset_2, offset_2 = 0; + if (offset_1 > maxRep) + offsetSaved = offset_1, offset_1 = 0; + } + + /* Main Search Loop */ + while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */ + size_t mLength; + size_t const h2 = ZSTD_hashPtr(ip, hBitsL, 8); + size_t const h = ZSTD_hashPtr(ip, hBitsS, mls); + U32 const curr = (U32)(ip - base); + U32 const matchIndexL = hashLong[h2]; + U32 const matchIndexS = hashSmall[h]; + const BYTE *matchLong = base + matchIndexL; + const BYTE *match = base + matchIndexS; + hashLong[h2] = hashSmall[h] = curr; /* update hash tables */ + + if ((offset_1 > 0) & (ZSTD_read32(ip + 1 - offset_1) == ZSTD_read32(ip + 1))) { /* note : by construction, offset_1 <= curr */ + mLength = ZSTD_count(ip + 1 + 4, ip + 1 + 4 - offset_1, iend) + 4; + ip++; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH); + } else { + U32 offset; + if ((matchIndexL > lowestIndex) && (ZSTD_read64(matchLong) == ZSTD_read64(ip))) { + mLength = ZSTD_count(ip + 8, matchLong + 8, iend) + 8; + offset = (U32)(ip - matchLong); + while (((ip > anchor) & (matchLong > lowest)) && (ip[-1] == matchLong[-1])) { + ip--; + matchLong--; + mLength++; + } /* catch up */ + } else if ((matchIndexS > lowestIndex) && (ZSTD_read32(match) == ZSTD_read32(ip))) { + size_t const h3 = ZSTD_hashPtr(ip + 1, hBitsL, 8); + U32 const matchIndex3 = hashLong[h3]; + const BYTE *match3 = base + matchIndex3; + hashLong[h3] = curr + 1; + if ((matchIndex3 > lowestIndex) && (ZSTD_read64(match3) == ZSTD_read64(ip + 1))) { + mLength = ZSTD_count(ip + 9, match3 + 8, iend) + 8; + ip++; + offset = (U32)(ip - match3); + while (((ip > anchor) & (match3 > lowest)) && (ip[-1] == match3[-1])) { + ip--; + match3--; + mLength++; + } /* catch up */ + } else { + mLength = ZSTD_count(ip + 4, match + 4, iend) + 4; + offset = (U32)(ip - match); + while (((ip > anchor) & (match > lowest)) && (ip[-1] == match[-1])) { + ip--; + match--; + mLength++; + } /* catch up */ + } + } else { + ip += ((ip - anchor) >> g_searchStrength) + 1; + continue; + } + + offset_2 = offset_1; + offset_1 = offset; + + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH); + } + + /* match found */ + ip += mLength; + anchor = ip; + + if (ip <= ilimit) { + /* Fill Table */ + hashLong[ZSTD_hashPtr(base + curr + 2, hBitsL, 8)] = hashSmall[ZSTD_hashPtr(base + curr + 2, hBitsS, mls)] = + curr + 2; /* here because curr+2 could be > iend-8 */ + hashLong[ZSTD_hashPtr(ip - 2, hBitsL, 8)] = hashSmall[ZSTD_hashPtr(ip - 2, hBitsS, mls)] = (U32)(ip - 2 - base); + + /* check immediate repcode */ + while ((ip <= ilimit) && ((offset_2 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) { + /* store sequence */ + size_t const rLength = ZSTD_count(ip + 4, ip + 4 - offset_2, iend) + 4; + { + U32 const tmpOff = offset_2; + offset_2 = offset_1; + offset_1 = tmpOff; + } /* swap offset_2 <=> offset_1 */ + hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip - base); + hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip - base); + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, rLength - MINMATCH); + ip += rLength; + anchor = ip; + continue; /* faster when present ... (?) */ + } + } + } + + /* save reps for next block */ + cctx->repToConfirm[0] = offset_1 ? offset_1 : offsetSaved; + cctx->repToConfirm[1] = offset_2 ? offset_2 : offsetSaved; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_doubleFast(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + const U32 mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_doubleFast_generic(ctx, src, srcSize, 7); return; + } +} + +static void ZSTD_compressBlock_doubleFast_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 mls) +{ + U32 *const hashLong = ctx->hashTable; + U32 const hBitsL = ctx->params.cParams.hashLog; + U32 *const hashSmall = ctx->chainTable; + U32 const hBitsS = ctx->params.cParams.chainLog; + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const base = ctx->base; + const BYTE *const dictBase = ctx->dictBase; + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const U32 lowestIndex = ctx->lowLimit; + const BYTE *const dictStart = dictBase + lowestIndex; + const U32 dictLimit = ctx->dictLimit; + const BYTE *const lowPrefixPtr = base + dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1]; + + /* Search Loop */ + while (ip < ilimit) { /* < instead of <=, because (ip+1) */ + const size_t hSmall = ZSTD_hashPtr(ip, hBitsS, mls); + const U32 matchIndex = hashSmall[hSmall]; + const BYTE *matchBase = matchIndex < dictLimit ? dictBase : base; + const BYTE *match = matchBase + matchIndex; + + const size_t hLong = ZSTD_hashPtr(ip, hBitsL, 8); + const U32 matchLongIndex = hashLong[hLong]; + const BYTE *matchLongBase = matchLongIndex < dictLimit ? dictBase : base; + const BYTE *matchLong = matchLongBase + matchLongIndex; + + const U32 curr = (U32)(ip - base); + const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */ + const BYTE *repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *repMatch = repBase + repIndex; + size_t mLength; + hashSmall[hSmall] = hashLong[hLong] = curr; /* update hash table */ + + if ((((U32)((dictLimit - 1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > lowestIndex)) && + (ZSTD_read32(repMatch) == ZSTD_read32(ip + 1))) { + const BYTE *repMatchEnd = repIndex < dictLimit ? dictEnd : iend; + mLength = ZSTD_count_2segments(ip + 1 + 4, repMatch + 4, iend, repMatchEnd, lowPrefixPtr) + 4; + ip++; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, 0, mLength - MINMATCH); + } else { + if ((matchLongIndex > lowestIndex) && (ZSTD_read64(matchLong) == ZSTD_read64(ip))) { + const BYTE *matchEnd = matchLongIndex < dictLimit ? dictEnd : iend; + const BYTE *lowMatchPtr = matchLongIndex < dictLimit ? dictStart : lowPrefixPtr; + U32 offset; + mLength = ZSTD_count_2segments(ip + 8, matchLong + 8, iend, matchEnd, lowPrefixPtr) + 8; + offset = curr - matchLongIndex; + while (((ip > anchor) & (matchLong > lowMatchPtr)) && (ip[-1] == matchLong[-1])) { + ip--; + matchLong--; + mLength++; + } /* catch up */ + offset_2 = offset_1; + offset_1 = offset; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH); + + } else if ((matchIndex > lowestIndex) && (ZSTD_read32(match) == ZSTD_read32(ip))) { + size_t const h3 = ZSTD_hashPtr(ip + 1, hBitsL, 8); + U32 const matchIndex3 = hashLong[h3]; + const BYTE *const match3Base = matchIndex3 < dictLimit ? dictBase : base; + const BYTE *match3 = match3Base + matchIndex3; + U32 offset; + hashLong[h3] = curr + 1; + if ((matchIndex3 > lowestIndex) && (ZSTD_read64(match3) == ZSTD_read64(ip + 1))) { + const BYTE *matchEnd = matchIndex3 < dictLimit ? dictEnd : iend; + const BYTE *lowMatchPtr = matchIndex3 < dictLimit ? dictStart : lowPrefixPtr; + mLength = ZSTD_count_2segments(ip + 9, match3 + 8, iend, matchEnd, lowPrefixPtr) + 8; + ip++; + offset = curr + 1 - matchIndex3; + while (((ip > anchor) & (match3 > lowMatchPtr)) && (ip[-1] == match3[-1])) { + ip--; + match3--; + mLength++; + } /* catch up */ + } else { + const BYTE *matchEnd = matchIndex < dictLimit ? dictEnd : iend; + const BYTE *lowMatchPtr = matchIndex < dictLimit ? dictStart : lowPrefixPtr; + mLength = ZSTD_count_2segments(ip + 4, match + 4, iend, matchEnd, lowPrefixPtr) + 4; + offset = curr - matchIndex; + while (((ip > anchor) & (match > lowMatchPtr)) && (ip[-1] == match[-1])) { + ip--; + match--; + mLength++; + } /* catch up */ + } + offset_2 = offset_1; + offset_1 = offset; + ZSTD_storeSeq(seqStorePtr, ip - anchor, anchor, offset + ZSTD_REP_MOVE, mLength - MINMATCH); + + } else { + ip += ((ip - anchor) >> g_searchStrength) + 1; + continue; + } + } + + /* found a match : store it */ + ip += mLength; + anchor = ip; + + if (ip <= ilimit) { + /* Fill Table */ + hashSmall[ZSTD_hashPtr(base + curr + 2, hBitsS, mls)] = curr + 2; + hashLong[ZSTD_hashPtr(base + curr + 2, hBitsL, 8)] = curr + 2; + hashSmall[ZSTD_hashPtr(ip - 2, hBitsS, mls)] = (U32)(ip - 2 - base); + hashLong[ZSTD_hashPtr(ip - 2, hBitsL, 8)] = (U32)(ip - 2 - base); + /* check immediate repcode */ + while (ip <= ilimit) { + U32 const curr2 = (U32)(ip - base); + U32 const repIndex2 = curr2 - offset_2; + const BYTE *repMatch2 = repIndex2 < dictLimit ? dictBase + repIndex2 : base + repIndex2; + if ((((U32)((dictLimit - 1) - repIndex2) >= 3) & (repIndex2 > lowestIndex)) /* intentional overflow */ + && (ZSTD_read32(repMatch2) == ZSTD_read32(ip))) { + const BYTE *const repEnd2 = repIndex2 < dictLimit ? dictEnd : iend; + size_t const repLength2 = + ZSTD_count_2segments(ip + EQUAL_READ32, repMatch2 + EQUAL_READ32, iend, repEnd2, lowPrefixPtr) + EQUAL_READ32; + U32 tmpOffset = offset_2; + offset_2 = offset_1; + offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */ + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, repLength2 - MINMATCH); + hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = curr2; + hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = curr2; + ip += repLength2; + anchor = ip; + continue; + } + break; + } + } + } + + /* save reps for next block */ + ctx->repToConfirm[0] = offset_1; + ctx->repToConfirm[1] = offset_2; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_doubleFast_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + U32 const mls = ctx->params.cParams.searchLength; + switch (mls) { + default: /* includes case 3 */ + case 4: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 4); return; + case 5: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 5); return; + case 6: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 6); return; + case 7: ZSTD_compressBlock_doubleFast_extDict_generic(ctx, src, srcSize, 7); return; + } +} + +/*-************************************* +* Binary Tree search +***************************************/ +/** ZSTD_insertBt1() : add one or multiple positions to tree. +* ip : assumed <= iend-8 . +* @return : nb of positions added */ +static U32 ZSTD_insertBt1(ZSTD_CCtx *zc, const BYTE *const ip, const U32 mls, const BYTE *const iend, U32 nbCompares, U32 extDict) +{ + U32 *const hashTable = zc->hashTable; + U32 const hashLog = zc->params.cParams.hashLog; + size_t const h = ZSTD_hashPtr(ip, hashLog, mls); + U32 *const bt = zc->chainTable; + U32 const btLog = zc->params.cParams.chainLog - 1; + U32 const btMask = (1 << btLog) - 1; + U32 matchIndex = hashTable[h]; + size_t commonLengthSmaller = 0, commonLengthLarger = 0; + const BYTE *const base = zc->base; + const BYTE *const dictBase = zc->dictBase; + const U32 dictLimit = zc->dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const BYTE *match; + const U32 curr = (U32)(ip - base); + const U32 btLow = btMask >= curr ? 0 : curr - btMask; + U32 *smallerPtr = bt + 2 * (curr & btMask); + U32 *largerPtr = smallerPtr + 1; + U32 dummy32; /* to be nullified at the end */ + U32 const windowLow = zc->lowLimit; + U32 matchEndIdx = curr + 8; + size_t bestLength = 8; + + hashTable[h] = curr; /* Update Hash Table */ + + while (nbCompares-- && (matchIndex > windowLow)) { + U32 *const nextPtr = bt + 2 * (matchIndex & btMask); + size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ + + if ((!extDict) || (matchIndex + matchLength >= dictLimit)) { + match = base + matchIndex; + if (match[matchLength] == ip[matchLength]) + matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iend) + 1; + } else { + match = dictBase + matchIndex; + matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iend, dictEnd, prefixStart); + if (matchIndex + matchLength >= dictLimit) + match = base + matchIndex; /* to prepare for next usage of match[matchLength] */ + } + + if (matchLength > bestLength) { + bestLength = matchLength; + if (matchLength > matchEndIdx - matchIndex) + matchEndIdx = matchIndex + (U32)matchLength; + } + + if (ip + matchLength == iend) /* equal : no way to know if inf or sup */ + break; /* drop , to guarantee consistency ; miss a bit of compression, but other solutions can corrupt the tree */ + + if (match[matchLength] < ip[matchLength]) { /* necessarily within correct buffer */ + /* match is smaller than curr */ + *smallerPtr = matchIndex; /* update smaller idx */ + commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */ + if (matchIndex <= btLow) { + smallerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */ + matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */ + } else { + /* match is larger than curr */ + *largerPtr = matchIndex; + commonLengthLarger = matchLength; + if (matchIndex <= btLow) { + largerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + largerPtr = nextPtr; + matchIndex = nextPtr[0]; + } + } + + *smallerPtr = *largerPtr = 0; + if (bestLength > 384) + return MIN(192, (U32)(bestLength - 384)); /* speed optimization */ + if (matchEndIdx > curr + 8) + return matchEndIdx - curr - 8; + return 1; +} + +static size_t ZSTD_insertBtAndFindBestMatch(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, size_t *offsetPtr, U32 nbCompares, const U32 mls, + U32 extDict) +{ + U32 *const hashTable = zc->hashTable; + U32 const hashLog = zc->params.cParams.hashLog; + size_t const h = ZSTD_hashPtr(ip, hashLog, mls); + U32 *const bt = zc->chainTable; + U32 const btLog = zc->params.cParams.chainLog - 1; + U32 const btMask = (1 << btLog) - 1; + U32 matchIndex = hashTable[h]; + size_t commonLengthSmaller = 0, commonLengthLarger = 0; + const BYTE *const base = zc->base; + const BYTE *const dictBase = zc->dictBase; + const U32 dictLimit = zc->dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const U32 curr = (U32)(ip - base); + const U32 btLow = btMask >= curr ? 0 : curr - btMask; + const U32 windowLow = zc->lowLimit; + U32 *smallerPtr = bt + 2 * (curr & btMask); + U32 *largerPtr = bt + 2 * (curr & btMask) + 1; + U32 matchEndIdx = curr + 8; + U32 dummy32; /* to be nullified at the end */ + size_t bestLength = 0; + + hashTable[h] = curr; /* Update Hash Table */ + + while (nbCompares-- && (matchIndex > windowLow)) { + U32 *const nextPtr = bt + 2 * (matchIndex & btMask); + size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ + const BYTE *match; + + if ((!extDict) || (matchIndex + matchLength >= dictLimit)) { + match = base + matchIndex; + if (match[matchLength] == ip[matchLength]) + matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iend) + 1; + } else { + match = dictBase + matchIndex; + matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iend, dictEnd, prefixStart); + if (matchIndex + matchLength >= dictLimit) + match = base + matchIndex; /* to prepare for next usage of match[matchLength] */ + } + + if (matchLength > bestLength) { + if (matchLength > matchEndIdx - matchIndex) + matchEndIdx = matchIndex + (U32)matchLength; + if ((4 * (int)(matchLength - bestLength)) > (int)(ZSTD_highbit32(curr - matchIndex + 1) - ZSTD_highbit32((U32)offsetPtr[0] + 1))) + bestLength = matchLength, *offsetPtr = ZSTD_REP_MOVE + curr - matchIndex; + if (ip + matchLength == iend) /* equal : no way to know if inf or sup */ + break; /* drop, to guarantee consistency (miss a little bit of compression) */ + } + + if (match[matchLength] < ip[matchLength]) { + /* match is smaller than curr */ + *smallerPtr = matchIndex; /* update smaller idx */ + commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */ + if (matchIndex <= btLow) { + smallerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */ + matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */ + } else { + /* match is larger than curr */ + *largerPtr = matchIndex; + commonLengthLarger = matchLength; + if (matchIndex <= btLow) { + largerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + largerPtr = nextPtr; + matchIndex = nextPtr[0]; + } + } + + *smallerPtr = *largerPtr = 0; + + zc->nextToUpdate = (matchEndIdx > curr + 8) ? matchEndIdx - 8 : curr + 1; + return bestLength; +} + +static void ZSTD_updateTree(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, const U32 nbCompares, const U32 mls) +{ + const BYTE *const base = zc->base; + const U32 target = (U32)(ip - base); + U32 idx = zc->nextToUpdate; + + while (idx < target) + idx += ZSTD_insertBt1(zc, base + idx, mls, iend, nbCompares, 0); +} + +/** ZSTD_BtFindBestMatch() : Tree updater, providing best match */ +static size_t ZSTD_BtFindBestMatch(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 mls) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 0); +} + +static size_t ZSTD_BtFindBestMatch_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 matchLengthSearch) +{ + switch (matchLengthSearch) { + default: /* includes case 3 */ + case 4: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4); + case 5: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5); + case 7: + case 6: return ZSTD_BtFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6); + } +} + +static void ZSTD_updateTree_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iend, const U32 nbCompares, const U32 mls) +{ + const BYTE *const base = zc->base; + const U32 target = (U32)(ip - base); + U32 idx = zc->nextToUpdate; + + while (idx < target) + idx += ZSTD_insertBt1(zc, base + idx, mls, iend, nbCompares, 1); +} + +/** Tree updater, providing best match */ +static size_t ZSTD_BtFindBestMatch_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, + const U32 mls) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndFindBestMatch(zc, ip, iLimit, offsetPtr, maxNbAttempts, mls, 1); +} + +static size_t ZSTD_BtFindBestMatch_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, + const U32 matchLengthSearch) +{ + switch (matchLengthSearch) { + default: /* includes case 3 */ + case 4: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4); + case 5: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5); + case 7: + case 6: return ZSTD_BtFindBestMatch_extDict(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6); + } +} + +/* ********************************* +* Hash Chain +***********************************/ +#define NEXT_IN_CHAIN(d, mask) chainTable[(d)&mask] + +/* Update chains up to ip (excluded) + Assumption : always within prefix (i.e. not within extDict) */ +FORCE_INLINE +U32 ZSTD_insertAndFindFirstIndex(ZSTD_CCtx *zc, const BYTE *ip, U32 mls) +{ + U32 *const hashTable = zc->hashTable; + const U32 hashLog = zc->params.cParams.hashLog; + U32 *const chainTable = zc->chainTable; + const U32 chainMask = (1 << zc->params.cParams.chainLog) - 1; + const BYTE *const base = zc->base; + const U32 target = (U32)(ip - base); + U32 idx = zc->nextToUpdate; + + while (idx < target) { /* catch up */ + size_t const h = ZSTD_hashPtr(base + idx, hashLog, mls); + NEXT_IN_CHAIN(idx, chainMask) = hashTable[h]; + hashTable[h] = idx; + idx++; + } + + zc->nextToUpdate = target; + return hashTable[ZSTD_hashPtr(ip, hashLog, mls)]; +} + +/* inlining is important to hardwire a hot branch (template emulation) */ +FORCE_INLINE +size_t ZSTD_HcFindBestMatch_generic(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *const ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, const U32 mls, + const U32 extDict) +{ + U32 *const chainTable = zc->chainTable; + const U32 chainSize = (1 << zc->params.cParams.chainLog); + const U32 chainMask = chainSize - 1; + const BYTE *const base = zc->base; + const BYTE *const dictBase = zc->dictBase; + const U32 dictLimit = zc->dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const U32 lowLimit = zc->lowLimit; + const U32 curr = (U32)(ip - base); + const U32 minChain = curr > chainSize ? curr - chainSize : 0; + int nbAttempts = maxNbAttempts; + size_t ml = EQUAL_READ32 - 1; + + /* HC4 match finder */ + U32 matchIndex = ZSTD_insertAndFindFirstIndex(zc, ip, mls); + + for (; (matchIndex > lowLimit) & (nbAttempts > 0); nbAttempts--) { + const BYTE *match; + size_t currMl = 0; + if ((!extDict) || matchIndex >= dictLimit) { + match = base + matchIndex; + if (match[ml] == ip[ml]) /* potentially better */ + currMl = ZSTD_count(ip, match, iLimit); + } else { + match = dictBase + matchIndex; + if (ZSTD_read32(match) == ZSTD_read32(ip)) /* assumption : matchIndex <= dictLimit-4 (by table construction) */ + currMl = ZSTD_count_2segments(ip + EQUAL_READ32, match + EQUAL_READ32, iLimit, dictEnd, prefixStart) + EQUAL_READ32; + } + + /* save best solution */ + if (currMl > ml) { + ml = currMl; + *offsetPtr = curr - matchIndex + ZSTD_REP_MOVE; + if (ip + currMl == iLimit) + break; /* best possible, and avoid read overflow*/ + } + + if (matchIndex <= minChain) + break; + matchIndex = NEXT_IN_CHAIN(matchIndex, chainMask); + } + + return ml; +} + +FORCE_INLINE size_t ZSTD_HcFindBestMatch_selectMLS(ZSTD_CCtx *zc, const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, + const U32 matchLengthSearch) +{ + switch (matchLengthSearch) { + default: /* includes case 3 */ + case 4: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 0); + case 5: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 0); + case 7: + case 6: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 0); + } +} + +FORCE_INLINE size_t ZSTD_HcFindBestMatch_extDict_selectMLS(ZSTD_CCtx *zc, const BYTE *ip, const BYTE *const iLimit, size_t *offsetPtr, const U32 maxNbAttempts, + const U32 matchLengthSearch) +{ + switch (matchLengthSearch) { + default: /* includes case 3 */ + case 4: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 4, 1); + case 5: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 5, 1); + case 7: + case 6: return ZSTD_HcFindBestMatch_generic(zc, ip, iLimit, offsetPtr, maxNbAttempts, 6, 1); + } +} + +/* ******************************* +* Common parser - lazy strategy +*********************************/ +FORCE_INLINE +void ZSTD_compressBlock_lazy_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 searchMethod, const U32 depth) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base + ctx->dictLimit; + + U32 const maxSearches = 1 << ctx->params.cParams.searchLog; + U32 const mls = ctx->params.cParams.searchLength; + + typedef size_t (*searchMax_f)(ZSTD_CCtx * zc, const BYTE *ip, const BYTE *iLimit, size_t *offsetPtr, U32 maxNbAttempts, U32 matchLengthSearch); + searchMax_f const searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS : ZSTD_HcFindBestMatch_selectMLS; + U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1], savedOffset = 0; + + /* init */ + ip += (ip == base); + ctx->nextToUpdate3 = ctx->nextToUpdate; + { + U32 const maxRep = (U32)(ip - base); + if (offset_2 > maxRep) + savedOffset = offset_2, offset_2 = 0; + if (offset_1 > maxRep) + savedOffset = offset_1, offset_1 = 0; + } + + /* Match Loop */ + while (ip < ilimit) { + size_t matchLength = 0; + size_t offset = 0; + const BYTE *start = ip + 1; + + /* check repCode */ + if ((offset_1 > 0) & (ZSTD_read32(ip + 1) == ZSTD_read32(ip + 1 - offset_1))) { + /* repcode : we take it */ + matchLength = ZSTD_count(ip + 1 + EQUAL_READ32, ip + 1 + EQUAL_READ32 - offset_1, iend) + EQUAL_READ32; + if (depth == 0) + goto _storeSequence; + } + + /* first search (depth 0) */ + { + size_t offsetFound = 99999999; + size_t const ml2 = searchMax(ctx, ip, iend, &offsetFound, maxSearches, mls); + if (ml2 > matchLength) + matchLength = ml2, start = ip, offset = offsetFound; + } + + if (matchLength < EQUAL_READ32) { + ip += ((ip - anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */ + continue; + } + + /* let's try to find a better solution */ + if (depth >= 1) + while (ip < ilimit) { + ip++; + if ((offset) && ((offset_1 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_1)))) { + size_t const mlRep = ZSTD_count(ip + EQUAL_READ32, ip + EQUAL_READ32 - offset_1, iend) + EQUAL_READ32; + int const gain2 = (int)(mlRep * 3); + int const gain1 = (int)(matchLength * 3 - ZSTD_highbit32((U32)offset + 1) + 1); + if ((mlRep >= EQUAL_READ32) && (gain2 > gain1)) + matchLength = mlRep, offset = 0, start = ip; + } + { + size_t offset2 = 99999999; + size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls); + int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */ + int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 4); + if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) { + matchLength = ml2, offset = offset2, start = ip; + continue; /* search a better one */ + } + } + + /* let's find an even better one */ + if ((depth == 2) && (ip < ilimit)) { + ip++; + if ((offset) && ((offset_1 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_1)))) { + size_t const ml2 = ZSTD_count(ip + EQUAL_READ32, ip + EQUAL_READ32 - offset_1, iend) + EQUAL_READ32; + int const gain2 = (int)(ml2 * 4); + int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 1); + if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) + matchLength = ml2, offset = 0, start = ip; + } + { + size_t offset2 = 99999999; + size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls); + int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */ + int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 7); + if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) { + matchLength = ml2, offset = offset2, start = ip; + continue; + } + } + } + break; /* nothing found : store previous solution */ + } + + /* NOTE: + * start[-offset+ZSTD_REP_MOVE-1] is undefined behavior. + * (-offset+ZSTD_REP_MOVE-1) is unsigned, and is added to start, which + * overflows the pointer, which is undefined behavior. + */ + /* catch up */ + if (offset) { + while ((start > anchor) && (start > base + offset - ZSTD_REP_MOVE) && + (start[-1] == (start-offset+ZSTD_REP_MOVE)[-1])) /* only search for offset within prefix */ + { + start--; + matchLength++; + } + offset_2 = offset_1; + offset_1 = (U32)(offset - ZSTD_REP_MOVE); + } + + /* store sequence */ +_storeSequence: + { + size_t const litLength = start - anchor; + ZSTD_storeSeq(seqStorePtr, litLength, anchor, (U32)offset, matchLength - MINMATCH); + anchor = ip = start + matchLength; + } + + /* check immediate repcode */ + while ((ip <= ilimit) && ((offset_2 > 0) & (ZSTD_read32(ip) == ZSTD_read32(ip - offset_2)))) { + /* store sequence */ + matchLength = ZSTD_count(ip + EQUAL_READ32, ip + EQUAL_READ32 - offset_2, iend) + EQUAL_READ32; + offset = offset_2; + offset_2 = offset_1; + offset_1 = (U32)offset; /* swap repcodes */ + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength - MINMATCH); + ip += matchLength; + anchor = ip; + continue; /* faster when present ... (?) */ + } + } + + /* Save reps for next block */ + ctx->repToConfirm[0] = offset_1 ? offset_1 : savedOffset; + ctx->repToConfirm[1] = offset_2 ? offset_2 : savedOffset; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +static void ZSTD_compressBlock_btlazy2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 1, 2); } + +static void ZSTD_compressBlock_lazy2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 2); } + +static void ZSTD_compressBlock_lazy(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 1); } + +static void ZSTD_compressBlock_greedy(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_generic(ctx, src, srcSize, 0, 0); } + +FORCE_INLINE +void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const U32 searchMethod, const U32 depth) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base; + const U32 dictLimit = ctx->dictLimit; + const U32 lowestIndex = ctx->lowLimit; + const BYTE *const prefixStart = base + dictLimit; + const BYTE *const dictBase = ctx->dictBase; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const dictStart = dictBase + ctx->lowLimit; + + const U32 maxSearches = 1 << ctx->params.cParams.searchLog; + const U32 mls = ctx->params.cParams.searchLength; + + typedef size_t (*searchMax_f)(ZSTD_CCtx * zc, const BYTE *ip, const BYTE *iLimit, size_t *offsetPtr, U32 maxNbAttempts, U32 matchLengthSearch); + searchMax_f searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS_extDict : ZSTD_HcFindBestMatch_extDict_selectMLS; + + U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1]; + + /* init */ + ctx->nextToUpdate3 = ctx->nextToUpdate; + ip += (ip == prefixStart); + + /* Match Loop */ + while (ip < ilimit) { + size_t matchLength = 0; + size_t offset = 0; + const BYTE *start = ip + 1; + U32 curr = (U32)(ip - base); + + /* check repCode */ + { + const U32 repIndex = (U32)(curr + 1 - offset_1); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + if (ZSTD_read32(ip + 1) == ZSTD_read32(repMatch)) { + /* repcode detected we should take it */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + matchLength = + ZSTD_count_2segments(ip + 1 + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32; + if (depth == 0) + goto _storeSequence; + } + } + + /* first search (depth 0) */ + { + size_t offsetFound = 99999999; + size_t const ml2 = searchMax(ctx, ip, iend, &offsetFound, maxSearches, mls); + if (ml2 > matchLength) + matchLength = ml2, start = ip, offset = offsetFound; + } + + if (matchLength < EQUAL_READ32) { + ip += ((ip - anchor) >> g_searchStrength) + 1; /* jump faster over incompressible sections */ + continue; + } + + /* let's try to find a better solution */ + if (depth >= 1) + while (ip < ilimit) { + ip++; + curr++; + /* check repCode */ + if (offset) { + const U32 repIndex = (U32)(curr - offset_1); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + if (ZSTD_read32(ip) == ZSTD_read32(repMatch)) { + /* repcode detected */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + size_t const repLength = + ZSTD_count_2segments(ip + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repEnd, prefixStart) + + EQUAL_READ32; + int const gain2 = (int)(repLength * 3); + int const gain1 = (int)(matchLength * 3 - ZSTD_highbit32((U32)offset + 1) + 1); + if ((repLength >= EQUAL_READ32) && (gain2 > gain1)) + matchLength = repLength, offset = 0, start = ip; + } + } + + /* search match, depth 1 */ + { + size_t offset2 = 99999999; + size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls); + int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */ + int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 4); + if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) { + matchLength = ml2, offset = offset2, start = ip; + continue; /* search a better one */ + } + } + + /* let's find an even better one */ + if ((depth == 2) && (ip < ilimit)) { + ip++; + curr++; + /* check repCode */ + if (offset) { + const U32 repIndex = (U32)(curr - offset_1); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + if (ZSTD_read32(ip) == ZSTD_read32(repMatch)) { + /* repcode detected */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + size_t repLength = ZSTD_count_2segments(ip + EQUAL_READ32, repMatch + EQUAL_READ32, iend, + repEnd, prefixStart) + + EQUAL_READ32; + int gain2 = (int)(repLength * 4); + int gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 1); + if ((repLength >= EQUAL_READ32) && (gain2 > gain1)) + matchLength = repLength, offset = 0, start = ip; + } + } + + /* search match, depth 2 */ + { + size_t offset2 = 99999999; + size_t const ml2 = searchMax(ctx, ip, iend, &offset2, maxSearches, mls); + int const gain2 = (int)(ml2 * 4 - ZSTD_highbit32((U32)offset2 + 1)); /* raw approx */ + int const gain1 = (int)(matchLength * 4 - ZSTD_highbit32((U32)offset + 1) + 7); + if ((ml2 >= EQUAL_READ32) && (gain2 > gain1)) { + matchLength = ml2, offset = offset2, start = ip; + continue; + } + } + } + break; /* nothing found : store previous solution */ + } + + /* catch up */ + if (offset) { + U32 const matchIndex = (U32)((start - base) - (offset - ZSTD_REP_MOVE)); + const BYTE *match = (matchIndex < dictLimit) ? dictBase + matchIndex : base + matchIndex; + const BYTE *const mStart = (matchIndex < dictLimit) ? dictStart : prefixStart; + while ((start > anchor) && (match > mStart) && (start[-1] == match[-1])) { + start--; + match--; + matchLength++; + } /* catch up */ + offset_2 = offset_1; + offset_1 = (U32)(offset - ZSTD_REP_MOVE); + } + + /* store sequence */ + _storeSequence : { + size_t const litLength = start - anchor; + ZSTD_storeSeq(seqStorePtr, litLength, anchor, (U32)offset, matchLength - MINMATCH); + anchor = ip = start + matchLength; + } + + /* check immediate repcode */ + while (ip <= ilimit) { + const U32 repIndex = (U32)((ip - base) - offset_2); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + if (ZSTD_read32(ip) == ZSTD_read32(repMatch)) { + /* repcode detected we should take it */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + matchLength = + ZSTD_count_2segments(ip + EQUAL_READ32, repMatch + EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32; + offset = offset_2; + offset_2 = offset_1; + offset_1 = (U32)offset; /* swap offset history */ + ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength - MINMATCH); + ip += matchLength; + anchor = ip; + continue; /* faster when present ... (?) */ + } + break; + } + } + + /* Save reps for next block */ + ctx->repToConfirm[0] = offset_1; + ctx->repToConfirm[1] = offset_2; + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +void ZSTD_compressBlock_greedy_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) { ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 0); } + +static void ZSTD_compressBlock_lazy_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 1); +} + +static void ZSTD_compressBlock_lazy2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 0, 2); +} + +static void ZSTD_compressBlock_btlazy2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ + ZSTD_compressBlock_lazy_extDict_generic(ctx, src, srcSize, 1, 2); +} + +/* The optimal parser */ +#include "zstd_opt.h" + +static void ZSTD_compressBlock_btopt(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 0); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +static void ZSTD_compressBlock_btopt2(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_generic(ctx, src, srcSize, 1); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +static void ZSTD_compressBlock_btopt_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 0); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +static void ZSTD_compressBlock_btopt2_extDict(ZSTD_CCtx *ctx, const void *src, size_t srcSize) +{ +#ifdef ZSTD_OPT_H_91842398743 + ZSTD_compressBlock_opt_extDict_generic(ctx, src, srcSize, 1); +#else + (void)ctx; + (void)src; + (void)srcSize; + return; +#endif +} + +typedef void (*ZSTD_blockCompressor)(ZSTD_CCtx *ctx, const void *src, size_t srcSize); + +static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict) +{ + static const ZSTD_blockCompressor blockCompressor[2][8] = { + {ZSTD_compressBlock_fast, ZSTD_compressBlock_doubleFast, ZSTD_compressBlock_greedy, ZSTD_compressBlock_lazy, ZSTD_compressBlock_lazy2, + ZSTD_compressBlock_btlazy2, ZSTD_compressBlock_btopt, ZSTD_compressBlock_btopt2}, + {ZSTD_compressBlock_fast_extDict, ZSTD_compressBlock_doubleFast_extDict, ZSTD_compressBlock_greedy_extDict, ZSTD_compressBlock_lazy_extDict, + ZSTD_compressBlock_lazy2_extDict, ZSTD_compressBlock_btlazy2_extDict, ZSTD_compressBlock_btopt_extDict, ZSTD_compressBlock_btopt2_extDict}}; + + return blockCompressor[extDict][(U32)strat]; +} + +static size_t ZSTD_compressBlock_internal(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->params.cParams.strategy, zc->lowLimit < zc->dictLimit); + const BYTE *const base = zc->base; + const BYTE *const istart = (const BYTE *)src; + const U32 curr = (U32)(istart - base); + if (srcSize < MIN_CBLOCK_SIZE + ZSTD_blockHeaderSize + 1) + return 0; /* don't even attempt compression below a certain srcSize */ + ZSTD_resetSeqStore(&(zc->seqStore)); + if (curr > zc->nextToUpdate + 384) + zc->nextToUpdate = curr - MIN(192, (U32)(curr - zc->nextToUpdate - 384)); /* update tree not updated after finding very long rep matches */ + blockCompressor(zc, src, srcSize); + return ZSTD_compressSequences(zc, dst, dstCapacity, srcSize); +} + +/*! ZSTD_compress_generic() : +* Compress a chunk of data into one or multiple blocks. +* All blocks will be terminated, all input will be consumed. +* Function will issue an error if there is not enough `dstCapacity` to hold the compressed content. +* Frame is supposed already started (header already produced) +* @return : compressed size, or an error code +*/ +static size_t ZSTD_compress_generic(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, U32 lastFrameChunk) +{ + size_t blockSize = cctx->blockSize; + size_t remaining = srcSize; + const BYTE *ip = (const BYTE *)src; + BYTE *const ostart = (BYTE *)dst; + BYTE *op = ostart; + U32 const maxDist = 1 << cctx->params.cParams.windowLog; + + if (cctx->params.fParams.checksumFlag && srcSize) + xxh64_update(&cctx->xxhState, src, srcSize); + + while (remaining) { + U32 const lastBlock = lastFrameChunk & (blockSize >= remaining); + size_t cSize; + + if (dstCapacity < ZSTD_blockHeaderSize + MIN_CBLOCK_SIZE) + return ERROR(dstSize_tooSmall); /* not enough space to store compressed block */ + if (remaining < blockSize) + blockSize = remaining; + + /* preemptive overflow correction */ + if (cctx->lowLimit > (3U << 29)) { + U32 const cycleMask = (1 << ZSTD_cycleLog(cctx->params.cParams.hashLog, cctx->params.cParams.strategy)) - 1; + U32 const curr = (U32)(ip - cctx->base); + U32 const newCurr = (curr & cycleMask) + (1 << cctx->params.cParams.windowLog); + U32 const correction = curr - newCurr; + ZSTD_STATIC_ASSERT(ZSTD_WINDOWLOG_MAX_64 <= 30); + ZSTD_reduceIndex(cctx, correction); + cctx->base += correction; + cctx->dictBase += correction; + cctx->lowLimit -= correction; + cctx->dictLimit -= correction; + if (cctx->nextToUpdate < correction) + cctx->nextToUpdate = 0; + else + cctx->nextToUpdate -= correction; + } + + if ((U32)(ip + blockSize - cctx->base) > cctx->loadedDictEnd + maxDist) { + /* enforce maxDist */ + U32 const newLowLimit = (U32)(ip + blockSize - cctx->base) - maxDist; + if (cctx->lowLimit < newLowLimit) + cctx->lowLimit = newLowLimit; + if (cctx->dictLimit < cctx->lowLimit) + cctx->dictLimit = cctx->lowLimit; + } + + cSize = ZSTD_compressBlock_internal(cctx, op + ZSTD_blockHeaderSize, dstCapacity - ZSTD_blockHeaderSize, ip, blockSize); + if (ZSTD_isError(cSize)) + return cSize; + + if (cSize == 0) { /* block is not compressible */ + U32 const cBlockHeader24 = lastBlock + (((U32)bt_raw) << 1) + (U32)(blockSize << 3); + if (blockSize + ZSTD_blockHeaderSize > dstCapacity) + return ERROR(dstSize_tooSmall); + ZSTD_writeLE32(op, cBlockHeader24); /* no pb, 4th byte will be overwritten */ + memcpy(op + ZSTD_blockHeaderSize, ip, blockSize); + cSize = ZSTD_blockHeaderSize + blockSize; + } else { + U32 const cBlockHeader24 = lastBlock + (((U32)bt_compressed) << 1) + (U32)(cSize << 3); + ZSTD_writeLE24(op, cBlockHeader24); + cSize += ZSTD_blockHeaderSize; + } + + remaining -= blockSize; + dstCapacity -= cSize; + ip += blockSize; + op += cSize; + } + + if (lastFrameChunk && (op > ostart)) + cctx->stage = ZSTDcs_ending; + return op - ostart; +} + +static size_t ZSTD_writeFrameHeader(void *dst, size_t dstCapacity, ZSTD_parameters params, U64 pledgedSrcSize, U32 dictID) +{ + BYTE *const op = (BYTE *)dst; + U32 const dictIDSizeCode = (dictID > 0) + (dictID >= 256) + (dictID >= 65536); /* 0-3 */ + U32 const checksumFlag = params.fParams.checksumFlag > 0; + U32 const windowSize = 1U << params.cParams.windowLog; + U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize >= pledgedSrcSize); + BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3); + U32 const fcsCode = + params.fParams.contentSizeFlag ? (pledgedSrcSize >= 256) + (pledgedSrcSize >= 65536 + 256) + (pledgedSrcSize >= 0xFFFFFFFFU) : 0; /* 0-3 */ + BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag << 2) + (singleSegment << 5) + (fcsCode << 6)); + size_t pos; + + if (dstCapacity < ZSTD_frameHeaderSize_max) + return ERROR(dstSize_tooSmall); + + ZSTD_writeLE32(dst, ZSTD_MAGICNUMBER); + op[4] = frameHeaderDecriptionByte; + pos = 5; + if (!singleSegment) + op[pos++] = windowLogByte; + switch (dictIDSizeCode) { + default: /* impossible */ + case 0: break; + case 1: + op[pos] = (BYTE)(dictID); + pos++; + break; + case 2: + ZSTD_writeLE16(op + pos, (U16)dictID); + pos += 2; + break; + case 3: + ZSTD_writeLE32(op + pos, dictID); + pos += 4; + break; + } + switch (fcsCode) { + default: /* impossible */ + case 0: + if (singleSegment) + op[pos++] = (BYTE)(pledgedSrcSize); + break; + case 1: + ZSTD_writeLE16(op + pos, (U16)(pledgedSrcSize - 256)); + pos += 2; + break; + case 2: + ZSTD_writeLE32(op + pos, (U32)(pledgedSrcSize)); + pos += 4; + break; + case 3: + ZSTD_writeLE64(op + pos, (U64)(pledgedSrcSize)); + pos += 8; + break; + } + return pos; +} + +static size_t ZSTD_compressContinue_internal(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, U32 frame, U32 lastFrameChunk) +{ + const BYTE *const ip = (const BYTE *)src; + size_t fhSize = 0; + + if (cctx->stage == ZSTDcs_created) + return ERROR(stage_wrong); /* missing init (ZSTD_compressBegin) */ + + if (frame && (cctx->stage == ZSTDcs_init)) { + fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, cctx->frameContentSize, cctx->dictID); + if (ZSTD_isError(fhSize)) + return fhSize; + dstCapacity -= fhSize; + dst = (char *)dst + fhSize; + cctx->stage = ZSTDcs_ongoing; + } + + /* Check if blocks follow each other */ + if (src != cctx->nextSrc) { + /* not contiguous */ + ptrdiff_t const delta = cctx->nextSrc - ip; + cctx->lowLimit = cctx->dictLimit; + cctx->dictLimit = (U32)(cctx->nextSrc - cctx->base); + cctx->dictBase = cctx->base; + cctx->base -= delta; + cctx->nextToUpdate = cctx->dictLimit; + if (cctx->dictLimit - cctx->lowLimit < HASH_READ_SIZE) + cctx->lowLimit = cctx->dictLimit; /* too small extDict */ + } + + /* if input and dictionary overlap : reduce dictionary (area presumed modified by input) */ + if ((ip + srcSize > cctx->dictBase + cctx->lowLimit) & (ip < cctx->dictBase + cctx->dictLimit)) { + ptrdiff_t const highInputIdx = (ip + srcSize) - cctx->dictBase; + U32 const lowLimitMax = (highInputIdx > (ptrdiff_t)cctx->dictLimit) ? cctx->dictLimit : (U32)highInputIdx; + cctx->lowLimit = lowLimitMax; + } + + cctx->nextSrc = ip + srcSize; + + if (srcSize) { + size_t const cSize = frame ? ZSTD_compress_generic(cctx, dst, dstCapacity, src, srcSize, lastFrameChunk) + : ZSTD_compressBlock_internal(cctx, dst, dstCapacity, src, srcSize); + if (ZSTD_isError(cSize)) + return cSize; + return cSize + fhSize; + } else + return fhSize; +} + +size_t ZSTD_compressContinue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1, 0); +} + +size_t ZSTD_getBlockSizeMax(ZSTD_CCtx *cctx) { return MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, 1 << cctx->params.cParams.windowLog); } + +size_t ZSTD_compressBlock(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t const blockSizeMax = ZSTD_getBlockSizeMax(cctx); + if (srcSize > blockSizeMax) + return ERROR(srcSize_wrong); + return ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 0, 0); +} + +/*! ZSTD_loadDictionaryContent() : + * @return : 0, or an error code + */ +static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx *zc, const void *src, size_t srcSize) +{ + const BYTE *const ip = (const BYTE *)src; + const BYTE *const iend = ip + srcSize; + + /* input becomes curr prefix */ + zc->lowLimit = zc->dictLimit; + zc->dictLimit = (U32)(zc->nextSrc - zc->base); + zc->dictBase = zc->base; + zc->base += ip - zc->nextSrc; + zc->nextToUpdate = zc->dictLimit; + zc->loadedDictEnd = zc->forceWindow ? 0 : (U32)(iend - zc->base); + + zc->nextSrc = iend; + if (srcSize <= HASH_READ_SIZE) + return 0; + + switch (zc->params.cParams.strategy) { + case ZSTD_fast: ZSTD_fillHashTable(zc, iend, zc->params.cParams.searchLength); break; + + case ZSTD_dfast: ZSTD_fillDoubleHashTable(zc, iend, zc->params.cParams.searchLength); break; + + case ZSTD_greedy: + case ZSTD_lazy: + case ZSTD_lazy2: + if (srcSize >= HASH_READ_SIZE) + ZSTD_insertAndFindFirstIndex(zc, iend - HASH_READ_SIZE, zc->params.cParams.searchLength); + break; + + case ZSTD_btlazy2: + case ZSTD_btopt: + case ZSTD_btopt2: + if (srcSize >= HASH_READ_SIZE) + ZSTD_updateTree(zc, iend - HASH_READ_SIZE, iend, 1 << zc->params.cParams.searchLog, zc->params.cParams.searchLength); + break; + + default: + return ERROR(GENERIC); /* strategy doesn't exist; impossible */ + } + + zc->nextToUpdate = (U32)(iend - zc->base); + return 0; +} + +/* Dictionaries that assign zero probability to symbols that show up causes problems + when FSE encoding. Refuse dictionaries that assign zero probability to symbols + that we may encounter during compression. + NOTE: This behavior is not standard and could be improved in the future. */ +static size_t ZSTD_checkDictNCount(short *normalizedCounter, unsigned dictMaxSymbolValue, unsigned maxSymbolValue) +{ + U32 s; + if (dictMaxSymbolValue < maxSymbolValue) + return ERROR(dictionary_corrupted); + for (s = 0; s <= maxSymbolValue; ++s) { + if (normalizedCounter[s] == 0) + return ERROR(dictionary_corrupted); + } + return 0; +} + +/* Dictionary format : + * See : + * https://github.com/facebook/zstd/blob/master/doc/zstd_compression_format.md#dictionary-format + */ +/*! ZSTD_loadZstdDictionary() : + * @return : 0, or an error code + * assumptions : magic number supposed already checked + * dictSize supposed > 8 + */ +static size_t ZSTD_loadZstdDictionary(ZSTD_CCtx *cctx, const void *dict, size_t dictSize) +{ + const BYTE *dictPtr = (const BYTE *)dict; + const BYTE *const dictEnd = dictPtr + dictSize; + short offcodeNCount[MaxOff + 1]; + unsigned offcodeMaxValue = MaxOff; + + dictPtr += 4; /* skip magic number */ + cctx->dictID = cctx->params.fParams.noDictIDFlag ? 0 : ZSTD_readLE32(dictPtr); + dictPtr += 4; + + { + size_t const hufHeaderSize = HUF_readCTable_wksp(cctx->hufTable, 255, dictPtr, dictEnd - dictPtr, cctx->tmpCounters, sizeof(cctx->tmpCounters)); + if (HUF_isError(hufHeaderSize)) + return ERROR(dictionary_corrupted); + dictPtr += hufHeaderSize; + } + + { + unsigned offcodeLog; + size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(offcodeHeaderSize)) + return ERROR(dictionary_corrupted); + if (offcodeLog > OffFSELog) + return ERROR(dictionary_corrupted); + /* Defer checking offcodeMaxValue because we need to know the size of the dictionary content */ + CHECK_E(FSE_buildCTable_wksp(cctx->offcodeCTable, offcodeNCount, offcodeMaxValue, offcodeLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)), + dictionary_corrupted); + dictPtr += offcodeHeaderSize; + } + + { + short matchlengthNCount[MaxML + 1]; + unsigned matchlengthMaxValue = MaxML, matchlengthLog; + size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(matchlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (matchlengthLog > MLFSELog) + return ERROR(dictionary_corrupted); + /* Every match length code must have non-zero probability */ + CHECK_F(ZSTD_checkDictNCount(matchlengthNCount, matchlengthMaxValue, MaxML)); + CHECK_E( + FSE_buildCTable_wksp(cctx->matchlengthCTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)), + dictionary_corrupted); + dictPtr += matchlengthHeaderSize; + } + + { + short litlengthNCount[MaxLL + 1]; + unsigned litlengthMaxValue = MaxLL, litlengthLog; + size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(litlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (litlengthLog > LLFSELog) + return ERROR(dictionary_corrupted); + /* Every literal length code must have non-zero probability */ + CHECK_F(ZSTD_checkDictNCount(litlengthNCount, litlengthMaxValue, MaxLL)); + CHECK_E(FSE_buildCTable_wksp(cctx->litlengthCTable, litlengthNCount, litlengthMaxValue, litlengthLog, cctx->tmpCounters, sizeof(cctx->tmpCounters)), + dictionary_corrupted); + dictPtr += litlengthHeaderSize; + } + + if (dictPtr + 12 > dictEnd) + return ERROR(dictionary_corrupted); + cctx->rep[0] = ZSTD_readLE32(dictPtr + 0); + cctx->rep[1] = ZSTD_readLE32(dictPtr + 4); + cctx->rep[2] = ZSTD_readLE32(dictPtr + 8); + dictPtr += 12; + + { + size_t const dictContentSize = (size_t)(dictEnd - dictPtr); + U32 offcodeMax = MaxOff; + if (dictContentSize <= ((U32)-1) - 128 KB) { + U32 const maxOffset = (U32)dictContentSize + 128 KB; /* The maximum offset that must be supported */ + offcodeMax = ZSTD_highbit32(maxOffset); /* Calculate minimum offset code required to represent maxOffset */ + } + /* All offset values <= dictContentSize + 128 KB must be representable */ + CHECK_F(ZSTD_checkDictNCount(offcodeNCount, offcodeMaxValue, MIN(offcodeMax, MaxOff))); + /* All repCodes must be <= dictContentSize and != 0*/ + { + U32 u; + for (u = 0; u < 3; u++) { + if (cctx->rep[u] == 0) + return ERROR(dictionary_corrupted); + if (cctx->rep[u] > dictContentSize) + return ERROR(dictionary_corrupted); + } + } + + cctx->flagStaticTables = 1; + cctx->flagStaticHufTable = HUF_repeat_valid; + return ZSTD_loadDictionaryContent(cctx, dictPtr, dictContentSize); + } +} + +/** ZSTD_compress_insertDictionary() : +* @return : 0, or an error code */ +static size_t ZSTD_compress_insertDictionary(ZSTD_CCtx *cctx, const void *dict, size_t dictSize) +{ + if ((dict == NULL) || (dictSize <= 8)) + return 0; + + /* dict as pure content */ + if ((ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC) || (cctx->forceRawDict)) + return ZSTD_loadDictionaryContent(cctx, dict, dictSize); + + /* dict as zstd dictionary */ + return ZSTD_loadZstdDictionary(cctx, dict, dictSize); +} + +/*! ZSTD_compressBegin_internal() : +* @return : 0, or an error code */ +static size_t ZSTD_compressBegin_internal(ZSTD_CCtx *cctx, const void *dict, size_t dictSize, ZSTD_parameters params, U64 pledgedSrcSize) +{ + ZSTD_compResetPolicy_e const crp = dictSize ? ZSTDcrp_fullReset : ZSTDcrp_continue; + CHECK_F(ZSTD_resetCCtx_advanced(cctx, params, pledgedSrcSize, crp)); + return ZSTD_compress_insertDictionary(cctx, dict, dictSize); +} + +/*! ZSTD_compressBegin_advanced() : +* @return : 0, or an error code */ +size_t ZSTD_compressBegin_advanced(ZSTD_CCtx *cctx, const void *dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize) +{ + /* compression parameters verification and optimization */ + CHECK_F(ZSTD_checkCParams(params.cParams)); + return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, pledgedSrcSize); +} + +size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx *cctx, const void *dict, size_t dictSize, int compressionLevel) +{ + ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize); + return ZSTD_compressBegin_internal(cctx, dict, dictSize, params, 0); +} + +size_t ZSTD_compressBegin(ZSTD_CCtx *cctx, int compressionLevel) { return ZSTD_compressBegin_usingDict(cctx, NULL, 0, compressionLevel); } + +/*! ZSTD_writeEpilogue() : +* Ends a frame. +* @return : nb of bytes written into dst (or an error code) */ +static size_t ZSTD_writeEpilogue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity) +{ + BYTE *const ostart = (BYTE *)dst; + BYTE *op = ostart; + size_t fhSize = 0; + + if (cctx->stage == ZSTDcs_created) + return ERROR(stage_wrong); /* init missing */ + + /* special case : empty frame */ + if (cctx->stage == ZSTDcs_init) { + fhSize = ZSTD_writeFrameHeader(dst, dstCapacity, cctx->params, 0, 0); + if (ZSTD_isError(fhSize)) + return fhSize; + dstCapacity -= fhSize; + op += fhSize; + cctx->stage = ZSTDcs_ongoing; + } + + if (cctx->stage != ZSTDcs_ending) { + /* write one last empty block, make it the "last" block */ + U32 const cBlockHeader24 = 1 /* last block */ + (((U32)bt_raw) << 1) + 0; + if (dstCapacity < 4) + return ERROR(dstSize_tooSmall); + ZSTD_writeLE32(op, cBlockHeader24); + op += ZSTD_blockHeaderSize; + dstCapacity -= ZSTD_blockHeaderSize; + } + + if (cctx->params.fParams.checksumFlag) { + U32 const checksum = (U32)xxh64_digest(&cctx->xxhState); + if (dstCapacity < 4) + return ERROR(dstSize_tooSmall); + ZSTD_writeLE32(op, checksum); + op += 4; + } + + cctx->stage = ZSTDcs_created; /* return to "created but no init" status */ + return op - ostart; +} + +size_t ZSTD_compressEnd(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t endResult; + size_t const cSize = ZSTD_compressContinue_internal(cctx, dst, dstCapacity, src, srcSize, 1, 1); + if (ZSTD_isError(cSize)) + return cSize; + endResult = ZSTD_writeEpilogue(cctx, (char *)dst + cSize, dstCapacity - cSize); + if (ZSTD_isError(endResult)) + return endResult; + return cSize + endResult; +} + +static size_t ZSTD_compress_internal(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize, + ZSTD_parameters params) +{ + CHECK_F(ZSTD_compressBegin_internal(cctx, dict, dictSize, params, srcSize)); + return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize); +} + +size_t ZSTD_compress_usingDict(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize, + ZSTD_parameters params) +{ + return ZSTD_compress_internal(ctx, dst, dstCapacity, src, srcSize, dict, dictSize, params); +} + +size_t ZSTD_compressCCtx(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, ZSTD_parameters params) +{ + return ZSTD_compress_internal(ctx, dst, dstCapacity, src, srcSize, NULL, 0, params); +} + +/* ===== Dictionary API ===== */ + +struct ZSTD_CDict_s { + void *dictBuffer; + const void *dictContent; + size_t dictContentSize; + ZSTD_CCtx *refContext; +}; /* typedef'd tp ZSTD_CDict within "zstd.h" */ + +size_t ZSTD_CDictWorkspaceBound(ZSTD_compressionParameters cParams) { return ZSTD_CCtxWorkspaceBound(cParams) + ZSTD_ALIGN(sizeof(ZSTD_CDict)); } + +static ZSTD_CDict *ZSTD_createCDict_advanced(const void *dictBuffer, size_t dictSize, unsigned byReference, ZSTD_parameters params, ZSTD_customMem customMem) +{ + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + { + ZSTD_CDict *const cdict = (ZSTD_CDict *)ZSTD_malloc(sizeof(ZSTD_CDict), customMem); + ZSTD_CCtx *const cctx = ZSTD_createCCtx_advanced(customMem); + + if (!cdict || !cctx) { + ZSTD_free(cdict, customMem); + ZSTD_freeCCtx(cctx); + return NULL; + } + + if ((byReference) || (!dictBuffer) || (!dictSize)) { + cdict->dictBuffer = NULL; + cdict->dictContent = dictBuffer; + } else { + void *const internalBuffer = ZSTD_malloc(dictSize, customMem); + if (!internalBuffer) { + ZSTD_free(cctx, customMem); + ZSTD_free(cdict, customMem); + return NULL; + } + memcpy(internalBuffer, dictBuffer, dictSize); + cdict->dictBuffer = internalBuffer; + cdict->dictContent = internalBuffer; + } + + { + size_t const errorCode = ZSTD_compressBegin_advanced(cctx, cdict->dictContent, dictSize, params, 0); + if (ZSTD_isError(errorCode)) { + ZSTD_free(cdict->dictBuffer, customMem); + ZSTD_free(cdict, customMem); + ZSTD_freeCCtx(cctx); + return NULL; + } + } + + cdict->refContext = cctx; + cdict->dictContentSize = dictSize; + return cdict; + } +} + +ZSTD_CDict *ZSTD_initCDict(const void *dict, size_t dictSize, ZSTD_parameters params, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + return ZSTD_createCDict_advanced(dict, dictSize, 1, params, stackMem); +} + +size_t ZSTD_freeCDict(ZSTD_CDict *cdict) +{ + if (cdict == NULL) + return 0; /* support free on NULL */ + { + ZSTD_customMem const cMem = cdict->refContext->customMem; + ZSTD_freeCCtx(cdict->refContext); + ZSTD_free(cdict->dictBuffer, cMem); + ZSTD_free(cdict, cMem); + return 0; + } +} + +static ZSTD_parameters ZSTD_getParamsFromCDict(const ZSTD_CDict *cdict) { return ZSTD_getParamsFromCCtx(cdict->refContext); } + +size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx *cctx, const ZSTD_CDict *cdict, unsigned long long pledgedSrcSize) +{ + if (cdict->dictContentSize) + CHECK_F(ZSTD_copyCCtx(cctx, cdict->refContext, pledgedSrcSize)) + else { + ZSTD_parameters params = cdict->refContext->params; + params.fParams.contentSizeFlag = (pledgedSrcSize > 0); + CHECK_F(ZSTD_compressBegin_advanced(cctx, NULL, 0, params, pledgedSrcSize)); + } + return 0; +} + +/*! ZSTD_compress_usingCDict() : +* Compression using a digested Dictionary. +* Faster startup than ZSTD_compress_usingDict(), recommended when same dictionary is used multiple times. +* Note that compression level is decided during dictionary creation */ +size_t ZSTD_compress_usingCDict(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_CDict *cdict) +{ + CHECK_F(ZSTD_compressBegin_usingCDict(cctx, cdict, srcSize)); + + if (cdict->refContext->params.fParams.contentSizeFlag == 1) { + cctx->params.fParams.contentSizeFlag = 1; + cctx->frameContentSize = srcSize; + } else { + cctx->params.fParams.contentSizeFlag = 0; + } + + return ZSTD_compressEnd(cctx, dst, dstCapacity, src, srcSize); +} + +/* ****************************************************************** +* Streaming +********************************************************************/ + +typedef enum { zcss_init, zcss_load, zcss_flush, zcss_final } ZSTD_cStreamStage; + +struct ZSTD_CStream_s { + ZSTD_CCtx *cctx; + ZSTD_CDict *cdictLocal; + const ZSTD_CDict *cdict; + char *inBuff; + size_t inBuffSize; + size_t inToCompress; + size_t inBuffPos; + size_t inBuffTarget; + size_t blockSize; + char *outBuff; + size_t outBuffSize; + size_t outBuffContentSize; + size_t outBuffFlushedSize; + ZSTD_cStreamStage stage; + U32 checksum; + U32 frameEnded; + U64 pledgedSrcSize; + U64 inputProcessed; + ZSTD_parameters params; + ZSTD_customMem customMem; +}; /* typedef'd to ZSTD_CStream within "zstd.h" */ + +size_t ZSTD_CStreamWorkspaceBound(ZSTD_compressionParameters cParams) +{ + size_t const inBuffSize = (size_t)1 << cParams.windowLog; + size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, inBuffSize); + size_t const outBuffSize = ZSTD_compressBound(blockSize) + 1; + + return ZSTD_CCtxWorkspaceBound(cParams) + ZSTD_ALIGN(sizeof(ZSTD_CStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize); +} + +ZSTD_CStream *ZSTD_createCStream_advanced(ZSTD_customMem customMem) +{ + ZSTD_CStream *zcs; + + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + zcs = (ZSTD_CStream *)ZSTD_malloc(sizeof(ZSTD_CStream), customMem); + if (zcs == NULL) + return NULL; + memset(zcs, 0, sizeof(ZSTD_CStream)); + memcpy(&zcs->customMem, &customMem, sizeof(ZSTD_customMem)); + zcs->cctx = ZSTD_createCCtx_advanced(customMem); + if (zcs->cctx == NULL) { + ZSTD_freeCStream(zcs); + return NULL; + } + return zcs; +} + +size_t ZSTD_freeCStream(ZSTD_CStream *zcs) +{ + if (zcs == NULL) + return 0; /* support free on NULL */ + { + ZSTD_customMem const cMem = zcs->customMem; + ZSTD_freeCCtx(zcs->cctx); + zcs->cctx = NULL; + ZSTD_freeCDict(zcs->cdictLocal); + zcs->cdictLocal = NULL; + ZSTD_free(zcs->inBuff, cMem); + zcs->inBuff = NULL; + ZSTD_free(zcs->outBuff, cMem); + zcs->outBuff = NULL; + ZSTD_free(zcs, cMem); + return 0; + } +} + +/*====== Initialization ======*/ + +size_t ZSTD_CStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; } +size_t ZSTD_CStreamOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + 4 /* 32-bits hash */; } + +static size_t ZSTD_resetCStream_internal(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize) +{ + if (zcs->inBuffSize == 0) + return ERROR(stage_wrong); /* zcs has not been init at least once => can't reset */ + + if (zcs->cdict) + CHECK_F(ZSTD_compressBegin_usingCDict(zcs->cctx, zcs->cdict, pledgedSrcSize)) + else + CHECK_F(ZSTD_compressBegin_advanced(zcs->cctx, NULL, 0, zcs->params, pledgedSrcSize)); + + zcs->inToCompress = 0; + zcs->inBuffPos = 0; + zcs->inBuffTarget = zcs->blockSize; + zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0; + zcs->stage = zcss_load; + zcs->frameEnded = 0; + zcs->pledgedSrcSize = pledgedSrcSize; + zcs->inputProcessed = 0; + return 0; /* ready to go */ +} + +size_t ZSTD_resetCStream(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize) +{ + + zcs->params.fParams.contentSizeFlag = (pledgedSrcSize > 0); + + return ZSTD_resetCStream_internal(zcs, pledgedSrcSize); +} + +static size_t ZSTD_initCStream_advanced(ZSTD_CStream *zcs, const void *dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize) +{ + /* allocate buffers */ + { + size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog; + if (zcs->inBuffSize < neededInBuffSize) { + zcs->inBuffSize = neededInBuffSize; + ZSTD_free(zcs->inBuff, zcs->customMem); + zcs->inBuff = (char *)ZSTD_malloc(neededInBuffSize, zcs->customMem); + if (zcs->inBuff == NULL) + return ERROR(memory_allocation); + } + zcs->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize); + } + if (zcs->outBuffSize < ZSTD_compressBound(zcs->blockSize) + 1) { + zcs->outBuffSize = ZSTD_compressBound(zcs->blockSize) + 1; + ZSTD_free(zcs->outBuff, zcs->customMem); + zcs->outBuff = (char *)ZSTD_malloc(zcs->outBuffSize, zcs->customMem); + if (zcs->outBuff == NULL) + return ERROR(memory_allocation); + } + + if (dict && dictSize >= 8) { + ZSTD_freeCDict(zcs->cdictLocal); + zcs->cdictLocal = ZSTD_createCDict_advanced(dict, dictSize, 0, params, zcs->customMem); + if (zcs->cdictLocal == NULL) + return ERROR(memory_allocation); + zcs->cdict = zcs->cdictLocal; + } else + zcs->cdict = NULL; + + zcs->checksum = params.fParams.checksumFlag > 0; + zcs->params = params; + + return ZSTD_resetCStream_internal(zcs, pledgedSrcSize); +} + +ZSTD_CStream *ZSTD_initCStream(ZSTD_parameters params, unsigned long long pledgedSrcSize, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + ZSTD_CStream *const zcs = ZSTD_createCStream_advanced(stackMem); + if (zcs) { + size_t const code = ZSTD_initCStream_advanced(zcs, NULL, 0, params, pledgedSrcSize); + if (ZSTD_isError(code)) { + return NULL; + } + } + return zcs; +} + +ZSTD_CStream *ZSTD_initCStream_usingCDict(const ZSTD_CDict *cdict, unsigned long long pledgedSrcSize, void *workspace, size_t workspaceSize) +{ + ZSTD_parameters const params = ZSTD_getParamsFromCDict(cdict); + ZSTD_CStream *const zcs = ZSTD_initCStream(params, pledgedSrcSize, workspace, workspaceSize); + if (zcs) { + zcs->cdict = cdict; + if (ZSTD_isError(ZSTD_resetCStream_internal(zcs, pledgedSrcSize))) { + return NULL; + } + } + return zcs; +} + +/*====== Compression ======*/ + +typedef enum { zsf_gather, zsf_flush, zsf_end } ZSTD_flush_e; + +ZSTD_STATIC size_t ZSTD_limitCopy(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t const length = MIN(dstCapacity, srcSize); + memcpy(dst, src, length); + return length; +} + +static size_t ZSTD_compressStream_generic(ZSTD_CStream *zcs, void *dst, size_t *dstCapacityPtr, const void *src, size_t *srcSizePtr, ZSTD_flush_e const flush) +{ + U32 someMoreWork = 1; + const char *const istart = (const char *)src; + const char *const iend = istart + *srcSizePtr; + const char *ip = istart; + char *const ostart = (char *)dst; + char *const oend = ostart + *dstCapacityPtr; + char *op = ostart; + + while (someMoreWork) { + switch (zcs->stage) { + case zcss_init: + return ERROR(init_missing); /* call ZBUFF_compressInit() first ! */ + + case zcss_load: + /* complete inBuffer */ + { + size_t const toLoad = zcs->inBuffTarget - zcs->inBuffPos; + size_t const loaded = ZSTD_limitCopy(zcs->inBuff + zcs->inBuffPos, toLoad, ip, iend - ip); + zcs->inBuffPos += loaded; + ip += loaded; + if ((zcs->inBuffPos == zcs->inToCompress) || (!flush && (toLoad != loaded))) { + someMoreWork = 0; + break; /* not enough input to get a full block : stop there, wait for more */ + } + } + /* compress curr block (note : this stage cannot be stopped in the middle) */ + { + void *cDst; + size_t cSize; + size_t const iSize = zcs->inBuffPos - zcs->inToCompress; + size_t oSize = oend - op; + if (oSize >= ZSTD_compressBound(iSize)) + cDst = op; /* compress directly into output buffer (avoid flush stage) */ + else + cDst = zcs->outBuff, oSize = zcs->outBuffSize; + cSize = (flush == zsf_end) ? ZSTD_compressEnd(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize) + : ZSTD_compressContinue(zcs->cctx, cDst, oSize, zcs->inBuff + zcs->inToCompress, iSize); + if (ZSTD_isError(cSize)) + return cSize; + if (flush == zsf_end) + zcs->frameEnded = 1; + /* prepare next block */ + zcs->inBuffTarget = zcs->inBuffPos + zcs->blockSize; + if (zcs->inBuffTarget > zcs->inBuffSize) + zcs->inBuffPos = 0, zcs->inBuffTarget = zcs->blockSize; /* note : inBuffSize >= blockSize */ + zcs->inToCompress = zcs->inBuffPos; + if (cDst == op) { + op += cSize; + break; + } /* no need to flush */ + zcs->outBuffContentSize = cSize; + zcs->outBuffFlushedSize = 0; + zcs->stage = zcss_flush; /* pass-through to flush stage */ + } + + case zcss_flush: { + size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize; + size_t const flushed = ZSTD_limitCopy(op, oend - op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush); + op += flushed; + zcs->outBuffFlushedSize += flushed; + if (toFlush != flushed) { + someMoreWork = 0; + break; + } /* dst too small to store flushed data : stop there */ + zcs->outBuffContentSize = zcs->outBuffFlushedSize = 0; + zcs->stage = zcss_load; + break; + } + + case zcss_final: + someMoreWork = 0; /* do nothing */ + break; + + default: + return ERROR(GENERIC); /* impossible */ + } + } + + *srcSizePtr = ip - istart; + *dstCapacityPtr = op - ostart; + zcs->inputProcessed += *srcSizePtr; + if (zcs->frameEnded) + return 0; + { + size_t hintInSize = zcs->inBuffTarget - zcs->inBuffPos; + if (hintInSize == 0) + hintInSize = zcs->blockSize; + return hintInSize; + } +} + +size_t ZSTD_compressStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output, ZSTD_inBuffer *input) +{ + size_t sizeRead = input->size - input->pos; + size_t sizeWritten = output->size - output->pos; + size_t const result = + ZSTD_compressStream_generic(zcs, (char *)(output->dst) + output->pos, &sizeWritten, (const char *)(input->src) + input->pos, &sizeRead, zsf_gather); + input->pos += sizeRead; + output->pos += sizeWritten; + return result; +} + +/*====== Finalize ======*/ + +/*! ZSTD_flushStream() : +* @return : amount of data remaining to flush */ +size_t ZSTD_flushStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output) +{ + size_t srcSize = 0; + size_t sizeWritten = output->size - output->pos; + size_t const result = ZSTD_compressStream_generic(zcs, (char *)(output->dst) + output->pos, &sizeWritten, &srcSize, + &srcSize, /* use a valid src address instead of NULL */ + zsf_flush); + output->pos += sizeWritten; + if (ZSTD_isError(result)) + return result; + return zcs->outBuffContentSize - zcs->outBuffFlushedSize; /* remaining to flush */ +} + +size_t ZSTD_endStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output) +{ + BYTE *const ostart = (BYTE *)(output->dst) + output->pos; + BYTE *const oend = (BYTE *)(output->dst) + output->size; + BYTE *op = ostart; + + if ((zcs->pledgedSrcSize) && (zcs->inputProcessed != zcs->pledgedSrcSize)) + return ERROR(srcSize_wrong); /* pledgedSrcSize not respected */ + + if (zcs->stage != zcss_final) { + /* flush whatever remains */ + size_t srcSize = 0; + size_t sizeWritten = output->size - output->pos; + size_t const notEnded = + ZSTD_compressStream_generic(zcs, ostart, &sizeWritten, &srcSize, &srcSize, zsf_end); /* use a valid src address instead of NULL */ + size_t const remainingToFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize; + op += sizeWritten; + if (remainingToFlush) { + output->pos += sizeWritten; + return remainingToFlush + ZSTD_BLOCKHEADERSIZE /* final empty block */ + (zcs->checksum * 4); + } + /* create epilogue */ + zcs->stage = zcss_final; + zcs->outBuffContentSize = !notEnded ? 0 : ZSTD_compressEnd(zcs->cctx, zcs->outBuff, zcs->outBuffSize, NULL, + 0); /* write epilogue, including final empty block, into outBuff */ + } + + /* flush epilogue */ + { + size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize; + size_t const flushed = ZSTD_limitCopy(op, oend - op, zcs->outBuff + zcs->outBuffFlushedSize, toFlush); + op += flushed; + zcs->outBuffFlushedSize += flushed; + output->pos += op - ostart; + if (toFlush == flushed) + zcs->stage = zcss_init; /* end reached */ + return toFlush - flushed; + } +} + +/*-===== Pre-defined compression levels =====-*/ + +#define ZSTD_DEFAULT_CLEVEL 1 +#define ZSTD_MAX_CLEVEL 22 +int ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; } + +static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEVEL + 1] = { + { + /* "default" */ + /* W, C, H, S, L, TL, strat */ + {18, 12, 12, 1, 7, 16, ZSTD_fast}, /* level 0 - never used */ + {19, 13, 14, 1, 7, 16, ZSTD_fast}, /* level 1 */ + {19, 15, 16, 1, 6, 16, ZSTD_fast}, /* level 2 */ + {20, 16, 17, 1, 5, 16, ZSTD_dfast}, /* level 3.*/ + {20, 18, 18, 1, 5, 16, ZSTD_dfast}, /* level 4.*/ + {20, 15, 18, 3, 5, 16, ZSTD_greedy}, /* level 5 */ + {21, 16, 19, 2, 5, 16, ZSTD_lazy}, /* level 6 */ + {21, 17, 20, 3, 5, 16, ZSTD_lazy}, /* level 7 */ + {21, 18, 20, 3, 5, 16, ZSTD_lazy2}, /* level 8 */ + {21, 20, 20, 3, 5, 16, ZSTD_lazy2}, /* level 9 */ + {21, 19, 21, 4, 5, 16, ZSTD_lazy2}, /* level 10 */ + {22, 20, 22, 4, 5, 16, ZSTD_lazy2}, /* level 11 */ + {22, 20, 22, 5, 5, 16, ZSTD_lazy2}, /* level 12 */ + {22, 21, 22, 5, 5, 16, ZSTD_lazy2}, /* level 13 */ + {22, 21, 22, 6, 5, 16, ZSTD_lazy2}, /* level 14 */ + {22, 21, 21, 5, 5, 16, ZSTD_btlazy2}, /* level 15 */ + {23, 22, 22, 5, 5, 16, ZSTD_btlazy2}, /* level 16 */ + {23, 21, 22, 4, 5, 24, ZSTD_btopt}, /* level 17 */ + {23, 23, 22, 6, 5, 32, ZSTD_btopt}, /* level 18 */ + {23, 23, 22, 6, 3, 48, ZSTD_btopt}, /* level 19 */ + {25, 25, 23, 7, 3, 64, ZSTD_btopt2}, /* level 20 */ + {26, 26, 23, 7, 3, 256, ZSTD_btopt2}, /* level 21 */ + {27, 27, 25, 9, 3, 512, ZSTD_btopt2}, /* level 22 */ + }, + { + /* for srcSize <= 256 KB */ + /* W, C, H, S, L, T, strat */ + {0, 0, 0, 0, 0, 0, ZSTD_fast}, /* level 0 - not used */ + {18, 13, 14, 1, 6, 8, ZSTD_fast}, /* level 1 */ + {18, 14, 13, 1, 5, 8, ZSTD_dfast}, /* level 2 */ + {18, 16, 15, 1, 5, 8, ZSTD_dfast}, /* level 3 */ + {18, 15, 17, 1, 5, 8, ZSTD_greedy}, /* level 4.*/ + {18, 16, 17, 4, 5, 8, ZSTD_greedy}, /* level 5.*/ + {18, 16, 17, 3, 5, 8, ZSTD_lazy}, /* level 6.*/ + {18, 17, 17, 4, 4, 8, ZSTD_lazy}, /* level 7 */ + {18, 17, 17, 4, 4, 8, ZSTD_lazy2}, /* level 8 */ + {18, 17, 17, 5, 4, 8, ZSTD_lazy2}, /* level 9 */ + {18, 17, 17, 6, 4, 8, ZSTD_lazy2}, /* level 10 */ + {18, 18, 17, 6, 4, 8, ZSTD_lazy2}, /* level 11.*/ + {18, 18, 17, 7, 4, 8, ZSTD_lazy2}, /* level 12.*/ + {18, 19, 17, 6, 4, 8, ZSTD_btlazy2}, /* level 13 */ + {18, 18, 18, 4, 4, 16, ZSTD_btopt}, /* level 14.*/ + {18, 18, 18, 4, 3, 16, ZSTD_btopt}, /* level 15.*/ + {18, 19, 18, 6, 3, 32, ZSTD_btopt}, /* level 16.*/ + {18, 19, 18, 8, 3, 64, ZSTD_btopt}, /* level 17.*/ + {18, 19, 18, 9, 3, 128, ZSTD_btopt}, /* level 18.*/ + {18, 19, 18, 10, 3, 256, ZSTD_btopt}, /* level 19.*/ + {18, 19, 18, 11, 3, 512, ZSTD_btopt2}, /* level 20.*/ + {18, 19, 18, 12, 3, 512, ZSTD_btopt2}, /* level 21.*/ + {18, 19, 18, 13, 3, 512, ZSTD_btopt2}, /* level 22.*/ + }, + { + /* for srcSize <= 128 KB */ + /* W, C, H, S, L, T, strat */ + {17, 12, 12, 1, 7, 8, ZSTD_fast}, /* level 0 - not used */ + {17, 12, 13, 1, 6, 8, ZSTD_fast}, /* level 1 */ + {17, 13, 16, 1, 5, 8, ZSTD_fast}, /* level 2 */ + {17, 16, 16, 2, 5, 8, ZSTD_dfast}, /* level 3 */ + {17, 13, 15, 3, 4, 8, ZSTD_greedy}, /* level 4 */ + {17, 15, 17, 4, 4, 8, ZSTD_greedy}, /* level 5 */ + {17, 16, 17, 3, 4, 8, ZSTD_lazy}, /* level 6 */ + {17, 15, 17, 4, 4, 8, ZSTD_lazy2}, /* level 7 */ + {17, 17, 17, 4, 4, 8, ZSTD_lazy2}, /* level 8 */ + {17, 17, 17, 5, 4, 8, ZSTD_lazy2}, /* level 9 */ + {17, 17, 17, 6, 4, 8, ZSTD_lazy2}, /* level 10 */ + {17, 17, 17, 7, 4, 8, ZSTD_lazy2}, /* level 11 */ + {17, 17, 17, 8, 4, 8, ZSTD_lazy2}, /* level 12 */ + {17, 18, 17, 6, 4, 8, ZSTD_btlazy2}, /* level 13.*/ + {17, 17, 17, 7, 3, 8, ZSTD_btopt}, /* level 14.*/ + {17, 17, 17, 7, 3, 16, ZSTD_btopt}, /* level 15.*/ + {17, 18, 17, 7, 3, 32, ZSTD_btopt}, /* level 16.*/ + {17, 18, 17, 7, 3, 64, ZSTD_btopt}, /* level 17.*/ + {17, 18, 17, 7, 3, 256, ZSTD_btopt}, /* level 18.*/ + {17, 18, 17, 8, 3, 256, ZSTD_btopt}, /* level 19.*/ + {17, 18, 17, 9, 3, 256, ZSTD_btopt2}, /* level 20.*/ + {17, 18, 17, 10, 3, 256, ZSTD_btopt2}, /* level 21.*/ + {17, 18, 17, 11, 3, 512, ZSTD_btopt2}, /* level 22.*/ + }, + { + /* for srcSize <= 16 KB */ + /* W, C, H, S, L, T, strat */ + {14, 12, 12, 1, 7, 6, ZSTD_fast}, /* level 0 - not used */ + {14, 14, 14, 1, 6, 6, ZSTD_fast}, /* level 1 */ + {14, 14, 14, 1, 4, 6, ZSTD_fast}, /* level 2 */ + {14, 14, 14, 1, 4, 6, ZSTD_dfast}, /* level 3.*/ + {14, 14, 14, 4, 4, 6, ZSTD_greedy}, /* level 4.*/ + {14, 14, 14, 3, 4, 6, ZSTD_lazy}, /* level 5.*/ + {14, 14, 14, 4, 4, 6, ZSTD_lazy2}, /* level 6 */ + {14, 14, 14, 5, 4, 6, ZSTD_lazy2}, /* level 7 */ + {14, 14, 14, 6, 4, 6, ZSTD_lazy2}, /* level 8.*/ + {14, 15, 14, 6, 4, 6, ZSTD_btlazy2}, /* level 9.*/ + {14, 15, 14, 3, 3, 6, ZSTD_btopt}, /* level 10.*/ + {14, 15, 14, 6, 3, 8, ZSTD_btopt}, /* level 11.*/ + {14, 15, 14, 6, 3, 16, ZSTD_btopt}, /* level 12.*/ + {14, 15, 14, 6, 3, 24, ZSTD_btopt}, /* level 13.*/ + {14, 15, 15, 6, 3, 48, ZSTD_btopt}, /* level 14.*/ + {14, 15, 15, 6, 3, 64, ZSTD_btopt}, /* level 15.*/ + {14, 15, 15, 6, 3, 96, ZSTD_btopt}, /* level 16.*/ + {14, 15, 15, 6, 3, 128, ZSTD_btopt}, /* level 17.*/ + {14, 15, 15, 6, 3, 256, ZSTD_btopt}, /* level 18.*/ + {14, 15, 15, 7, 3, 256, ZSTD_btopt}, /* level 19.*/ + {14, 15, 15, 8, 3, 256, ZSTD_btopt2}, /* level 20.*/ + {14, 15, 15, 9, 3, 256, ZSTD_btopt2}, /* level 21.*/ + {14, 15, 15, 10, 3, 256, ZSTD_btopt2}, /* level 22.*/ + }, +}; + +/*! ZSTD_getCParams() : +* @return ZSTD_compressionParameters structure for a selected compression level, `srcSize` and `dictSize`. +* Size values are optional, provide 0 if not known or unused */ +ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long srcSize, size_t dictSize) +{ + ZSTD_compressionParameters cp; + size_t const addedSize = srcSize ? 0 : 500; + U64 const rSize = srcSize + dictSize ? srcSize + dictSize + addedSize : (U64)-1; + U32 const tableID = (rSize <= 256 KB) + (rSize <= 128 KB) + (rSize <= 16 KB); /* intentional underflow for srcSizeHint == 0 */ + if (compressionLevel <= 0) + compressionLevel = ZSTD_DEFAULT_CLEVEL; /* 0 == default; no negative compressionLevel yet */ + if (compressionLevel > ZSTD_MAX_CLEVEL) + compressionLevel = ZSTD_MAX_CLEVEL; + cp = ZSTD_defaultCParameters[tableID][compressionLevel]; + if (ZSTD_32bits()) { /* auto-correction, for 32-bits mode */ + if (cp.windowLog > ZSTD_WINDOWLOG_MAX) + cp.windowLog = ZSTD_WINDOWLOG_MAX; + if (cp.chainLog > ZSTD_CHAINLOG_MAX) + cp.chainLog = ZSTD_CHAINLOG_MAX; + if (cp.hashLog > ZSTD_HASHLOG_MAX) + cp.hashLog = ZSTD_HASHLOG_MAX; + } + cp = ZSTD_adjustCParams(cp, srcSize, dictSize); + return cp; +} + +/*! ZSTD_getParams() : +* same as ZSTD_getCParams(), but @return a `ZSTD_parameters` object (instead of `ZSTD_compressionParameters`). +* All fields of `ZSTD_frameParameters` are set to default (0) */ +ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long srcSize, size_t dictSize) +{ + ZSTD_parameters params; + ZSTD_compressionParameters const cParams = ZSTD_getCParams(compressionLevel, srcSize, dictSize); + memset(¶ms, 0, sizeof(params)); + params.cParams = cParams; + return params; +} + +EXPORT_SYMBOL(ZSTD_maxCLevel); +EXPORT_SYMBOL(ZSTD_compressBound); + +EXPORT_SYMBOL(ZSTD_CCtxWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initCCtx); +EXPORT_SYMBOL(ZSTD_compressCCtx); +EXPORT_SYMBOL(ZSTD_compress_usingDict); + +EXPORT_SYMBOL(ZSTD_CDictWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initCDict); +EXPORT_SYMBOL(ZSTD_compress_usingCDict); + +EXPORT_SYMBOL(ZSTD_CStreamWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initCStream); +EXPORT_SYMBOL(ZSTD_initCStream_usingCDict); +EXPORT_SYMBOL(ZSTD_resetCStream); +EXPORT_SYMBOL(ZSTD_compressStream); +EXPORT_SYMBOL(ZSTD_flushStream); +EXPORT_SYMBOL(ZSTD_endStream); +EXPORT_SYMBOL(ZSTD_CStreamInSize); +EXPORT_SYMBOL(ZSTD_CStreamOutSize); + +EXPORT_SYMBOL(ZSTD_getCParams); +EXPORT_SYMBOL(ZSTD_getParams); +EXPORT_SYMBOL(ZSTD_checkCParams); +EXPORT_SYMBOL(ZSTD_adjustCParams); + +EXPORT_SYMBOL(ZSTD_compressBegin); +EXPORT_SYMBOL(ZSTD_compressBegin_usingDict); +EXPORT_SYMBOL(ZSTD_compressBegin_advanced); +EXPORT_SYMBOL(ZSTD_copyCCtx); +EXPORT_SYMBOL(ZSTD_compressBegin_usingCDict); +EXPORT_SYMBOL(ZSTD_compressContinue); +EXPORT_SYMBOL(ZSTD_compressEnd); + +EXPORT_SYMBOL(ZSTD_getBlockSizeMax); +EXPORT_SYMBOL(ZSTD_compressBlock); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("Zstd Compressor"); diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c new file mode 100644 index 000000000000..b17846725ca0 --- /dev/null +++ b/lib/zstd/decompress.c @@ -0,0 +1,2528 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/* *************************************************************** +* Tuning parameters +*****************************************************************/ +/*! +* MAXWINDOWSIZE_DEFAULT : +* maximum window size accepted by DStream, by default. +* Frames requiring more memory will be rejected. +*/ +#ifndef ZSTD_MAXWINDOWSIZE_DEFAULT +#define ZSTD_MAXWINDOWSIZE_DEFAULT ((1 << ZSTD_WINDOWLOG_MAX) + 1) /* defined within zstd.h */ +#endif + +/*-******************************************************* +* Dependencies +*********************************************************/ +#include "fse.h" +#include "huf.h" +#include "mem.h" /* low level memory routines */ +#include "zstd_internal.h" +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/string.h> /* memcpy, memmove, memset */ + +#define ZSTD_PREFETCH(ptr) __builtin_prefetch(ptr, 0, 0) + +/*-************************************* +* Macros +***************************************/ +#define ZSTD_isError ERR_isError /* for inlining */ +#define FSE_isError ERR_isError +#define HUF_isError ERR_isError + +/*_******************************************************* +* Memory operations +**********************************************************/ +static void ZSTD_copy4(void *dst, const void *src) { memcpy(dst, src, 4); } + +/*-************************************************************* +* Context management +***************************************************************/ +typedef enum { + ZSTDds_getFrameHeaderSize, + ZSTDds_decodeFrameHeader, + ZSTDds_decodeBlockHeader, + ZSTDds_decompressBlock, + ZSTDds_decompressLastBlock, + ZSTDds_checkChecksum, + ZSTDds_decodeSkippableHeader, + ZSTDds_skipFrame +} ZSTD_dStage; + +typedef struct { + FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)]; + FSE_DTable OFTable[FSE_DTABLE_SIZE_U32(OffFSELog)]; + FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)]; + HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */ + U64 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32 / 2]; + U32 rep[ZSTD_REP_NUM]; +} ZSTD_entropyTables_t; + +struct ZSTD_DCtx_s { + const FSE_DTable *LLTptr; + const FSE_DTable *MLTptr; + const FSE_DTable *OFTptr; + const HUF_DTable *HUFptr; + ZSTD_entropyTables_t entropy; + const void *previousDstEnd; /* detect continuity */ + const void *base; /* start of curr segment */ + const void *vBase; /* virtual start of previous segment if it was just before curr one */ + const void *dictEnd; /* end of previous segment */ + size_t expected; + ZSTD_frameParams fParams; + blockType_e bType; /* used in ZSTD_decompressContinue(), to transfer blockType between header decoding and block decoding stages */ + ZSTD_dStage stage; + U32 litEntropy; + U32 fseEntropy; + struct xxh64_state xxhState; + size_t headerSize; + U32 dictID; + const BYTE *litPtr; + ZSTD_customMem customMem; + size_t litSize; + size_t rleSize; + BYTE litBuffer[ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH]; + BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; +}; /* typedef'd to ZSTD_DCtx within "zstd.h" */ + +size_t ZSTD_DCtxWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DCtx)); } + +size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx) +{ + dctx->expected = ZSTD_frameHeaderSize_prefix; + dctx->stage = ZSTDds_getFrameHeaderSize; + dctx->previousDstEnd = NULL; + dctx->base = NULL; + dctx->vBase = NULL; + dctx->dictEnd = NULL; + dctx->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ + dctx->litEntropy = dctx->fseEntropy = 0; + dctx->dictID = 0; + ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.rep) == sizeof(repStartValue)); + memcpy(dctx->entropy.rep, repStartValue, sizeof(repStartValue)); /* initial repcodes */ + dctx->LLTptr = dctx->entropy.LLTable; + dctx->MLTptr = dctx->entropy.MLTable; + dctx->OFTptr = dctx->entropy.OFTable; + dctx->HUFptr = dctx->entropy.hufTable; + return 0; +} + +ZSTD_DCtx *ZSTD_createDCtx_advanced(ZSTD_customMem customMem) +{ + ZSTD_DCtx *dctx; + + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + dctx = (ZSTD_DCtx *)ZSTD_malloc(sizeof(ZSTD_DCtx), customMem); + if (!dctx) + return NULL; + memcpy(&dctx->customMem, &customMem, sizeof(customMem)); + ZSTD_decompressBegin(dctx); + return dctx; +} + +ZSTD_DCtx *ZSTD_initDCtx(void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + return ZSTD_createDCtx_advanced(stackMem); +} + +size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx) +{ + if (dctx == NULL) + return 0; /* support free on NULL */ + ZSTD_free(dctx, dctx->customMem); + return 0; /* reserved as a potential error code in the future */ +} + +void ZSTD_copyDCtx(ZSTD_DCtx *dstDCtx, const ZSTD_DCtx *srcDCtx) +{ + size_t const workSpaceSize = (ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH) + ZSTD_frameHeaderSize_max; + memcpy(dstDCtx, srcDCtx, sizeof(ZSTD_DCtx) - workSpaceSize); /* no need to copy workspace */ +} + +static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict); + +/*-************************************************************* +* Decompression section +***************************************************************/ + +/*! ZSTD_isFrame() : + * Tells if the content of `buffer` starts with a valid Frame Identifier. + * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0. + * Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled. + * Note 3 : Skippable Frame Identifiers are considered valid. */ +unsigned ZSTD_isFrame(const void *buffer, size_t size) +{ + if (size < 4) + return 0; + { + U32 const magic = ZSTD_readLE32(buffer); + if (magic == ZSTD_MAGICNUMBER) + return 1; + if ((magic & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) + return 1; + } + return 0; +} + +/** ZSTD_frameHeaderSize() : +* srcSize must be >= ZSTD_frameHeaderSize_prefix. +* @return : size of the Frame Header */ +static size_t ZSTD_frameHeaderSize(const void *src, size_t srcSize) +{ + if (srcSize < ZSTD_frameHeaderSize_prefix) + return ERROR(srcSize_wrong); + { + BYTE const fhd = ((const BYTE *)src)[4]; + U32 const dictID = fhd & 3; + U32 const singleSegment = (fhd >> 5) & 1; + U32 const fcsId = fhd >> 6; + return ZSTD_frameHeaderSize_prefix + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId] + (singleSegment && !fcsId); + } +} + +/** ZSTD_getFrameParams() : +* decode Frame Header, or require larger `srcSize`. +* @return : 0, `fparamsPtr` is correctly filled, +* >0, `srcSize` is too small, result is expected `srcSize`, +* or an error code, which can be tested using ZSTD_isError() */ +size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src, size_t srcSize) +{ + const BYTE *ip = (const BYTE *)src; + + if (srcSize < ZSTD_frameHeaderSize_prefix) + return ZSTD_frameHeaderSize_prefix; + if (ZSTD_readLE32(src) != ZSTD_MAGICNUMBER) { + if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + if (srcSize < ZSTD_skippableHeaderSize) + return ZSTD_skippableHeaderSize; /* magic number + skippable frame length */ + memset(fparamsPtr, 0, sizeof(*fparamsPtr)); + fparamsPtr->frameContentSize = ZSTD_readLE32((const char *)src + 4); + fparamsPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */ + return 0; + } + return ERROR(prefix_unknown); + } + + /* ensure there is enough `srcSize` to fully read/decode frame header */ + { + size_t const fhsize = ZSTD_frameHeaderSize(src, srcSize); + if (srcSize < fhsize) + return fhsize; + } + + { + BYTE const fhdByte = ip[4]; + size_t pos = 5; + U32 const dictIDSizeCode = fhdByte & 3; + U32 const checksumFlag = (fhdByte >> 2) & 1; + U32 const singleSegment = (fhdByte >> 5) & 1; + U32 const fcsID = fhdByte >> 6; + U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX; + U32 windowSize = 0; + U32 dictID = 0; + U64 frameContentSize = 0; + if ((fhdByte & 0x08) != 0) + return ERROR(frameParameter_unsupported); /* reserved bits, which must be zero */ + if (!singleSegment) { + BYTE const wlByte = ip[pos++]; + U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN; + if (windowLog > ZSTD_WINDOWLOG_MAX) + return ERROR(frameParameter_windowTooLarge); /* avoids issue with 1 << windowLog */ + windowSize = (1U << windowLog); + windowSize += (windowSize >> 3) * (wlByte & 7); + } + + switch (dictIDSizeCode) { + default: /* impossible */ + case 0: break; + case 1: + dictID = ip[pos]; + pos++; + break; + case 2: + dictID = ZSTD_readLE16(ip + pos); + pos += 2; + break; + case 3: + dictID = ZSTD_readLE32(ip + pos); + pos += 4; + break; + } + switch (fcsID) { + default: /* impossible */ + case 0: + if (singleSegment) + frameContentSize = ip[pos]; + break; + case 1: frameContentSize = ZSTD_readLE16(ip + pos) + 256; break; + case 2: frameContentSize = ZSTD_readLE32(ip + pos); break; + case 3: frameContentSize = ZSTD_readLE64(ip + pos); break; + } + if (!windowSize) + windowSize = (U32)frameContentSize; + if (windowSize > windowSizeMax) + return ERROR(frameParameter_windowTooLarge); + fparamsPtr->frameContentSize = frameContentSize; + fparamsPtr->windowSize = windowSize; + fparamsPtr->dictID = dictID; + fparamsPtr->checksumFlag = checksumFlag; + } + return 0; +} + +/** ZSTD_getFrameContentSize() : +* compatible with legacy mode +* @return : decompressed size of the single frame pointed to be `src` if known, otherwise +* - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined +* - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) */ +unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize) +{ + { + ZSTD_frameParams fParams; + if (ZSTD_getFrameParams(&fParams, src, srcSize) != 0) + return ZSTD_CONTENTSIZE_ERROR; + if (fParams.windowSize == 0) { + /* Either skippable or empty frame, size == 0 either way */ + return 0; + } else if (fParams.frameContentSize != 0) { + return fParams.frameContentSize; + } else { + return ZSTD_CONTENTSIZE_UNKNOWN; + } + } +} + +/** ZSTD_findDecompressedSize() : + * compatible with legacy mode + * `srcSize` must be the exact length of some number of ZSTD compressed and/or + * skippable frames + * @return : decompressed size of the frames contained */ +unsigned long long ZSTD_findDecompressedSize(const void *src, size_t srcSize) +{ + { + unsigned long long totalDstSize = 0; + while (srcSize >= ZSTD_frameHeaderSize_prefix) { + const U32 magicNumber = ZSTD_readLE32(src); + + if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + size_t skippableSize; + if (srcSize < ZSTD_skippableHeaderSize) + return ERROR(srcSize_wrong); + skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize; + if (srcSize < skippableSize) { + return ZSTD_CONTENTSIZE_ERROR; + } + + src = (const BYTE *)src + skippableSize; + srcSize -= skippableSize; + continue; + } + + { + unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize); + if (ret >= ZSTD_CONTENTSIZE_ERROR) + return ret; + + /* check for overflow */ + if (totalDstSize + ret < totalDstSize) + return ZSTD_CONTENTSIZE_ERROR; + totalDstSize += ret; + } + { + size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize); + if (ZSTD_isError(frameSrcSize)) { + return ZSTD_CONTENTSIZE_ERROR; + } + + src = (const BYTE *)src + frameSrcSize; + srcSize -= frameSrcSize; + } + } + + if (srcSize) { + return ZSTD_CONTENTSIZE_ERROR; + } + + return totalDstSize; + } +} + +/** ZSTD_decodeFrameHeader() : +* `headerSize` must be the size provided by ZSTD_frameHeaderSize(). +* @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */ +static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx *dctx, const void *src, size_t headerSize) +{ + size_t const result = ZSTD_getFrameParams(&(dctx->fParams), src, headerSize); + if (ZSTD_isError(result)) + return result; /* invalid header */ + if (result > 0) + return ERROR(srcSize_wrong); /* headerSize too small */ + if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID)) + return ERROR(dictionary_wrong); + if (dctx->fParams.checksumFlag) + xxh64_reset(&dctx->xxhState, 0); + return 0; +} + +typedef struct { + blockType_e blockType; + U32 lastBlock; + U32 origSize; +} blockProperties_t; + +/*! ZSTD_getcBlockSize() : +* Provides the size of compressed block from block header `src` */ +size_t ZSTD_getcBlockSize(const void *src, size_t srcSize, blockProperties_t *bpPtr) +{ + if (srcSize < ZSTD_blockHeaderSize) + return ERROR(srcSize_wrong); + { + U32 const cBlockHeader = ZSTD_readLE24(src); + U32 const cSize = cBlockHeader >> 3; + bpPtr->lastBlock = cBlockHeader & 1; + bpPtr->blockType = (blockType_e)((cBlockHeader >> 1) & 3); + bpPtr->origSize = cSize; /* only useful for RLE */ + if (bpPtr->blockType == bt_rle) + return 1; + if (bpPtr->blockType == bt_reserved) + return ERROR(corruption_detected); + return cSize; + } +} + +static size_t ZSTD_copyRawBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + if (srcSize > dstCapacity) + return ERROR(dstSize_tooSmall); + memcpy(dst, src, srcSize); + return srcSize; +} + +static size_t ZSTD_setRleBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize, size_t regenSize) +{ + if (srcSize != 1) + return ERROR(srcSize_wrong); + if (regenSize > dstCapacity) + return ERROR(dstSize_tooSmall); + memset(dst, *(const BYTE *)src, regenSize); + return regenSize; +} + +/*! ZSTD_decodeLiteralsBlock() : + @return : nb of bytes read from src (< srcSize ) */ +size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx *dctx, const void *src, size_t srcSize) /* note : srcSize < BLOCKSIZE */ +{ + if (srcSize < MIN_CBLOCK_SIZE) + return ERROR(corruption_detected); + + { + const BYTE *const istart = (const BYTE *)src; + symbolEncodingType_e const litEncType = (symbolEncodingType_e)(istart[0] & 3); + + switch (litEncType) { + case set_repeat: + if (dctx->litEntropy == 0) + return ERROR(dictionary_corrupted); + /* fall-through */ + case set_compressed: + if (srcSize < 5) + return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3 */ + { + size_t lhSize, litSize, litCSize; + U32 singleStream = 0; + U32 const lhlCode = (istart[0] >> 2) & 3; + U32 const lhc = ZSTD_readLE32(istart); + switch (lhlCode) { + case 0: + case 1: + default: /* note : default is impossible, since lhlCode into [0..3] */ + /* 2 - 2 - 10 - 10 */ + singleStream = !lhlCode; + lhSize = 3; + litSize = (lhc >> 4) & 0x3FF; + litCSize = (lhc >> 14) & 0x3FF; + break; + case 2: + /* 2 - 2 - 14 - 14 */ + lhSize = 4; + litSize = (lhc >> 4) & 0x3FFF; + litCSize = lhc >> 18; + break; + case 3: + /* 2 - 2 - 18 - 18 */ + lhSize = 5; + litSize = (lhc >> 4) & 0x3FFFF; + litCSize = (lhc >> 22) + (istart[4] << 10); + break; + } + if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) + return ERROR(corruption_detected); + if (litCSize + lhSize > srcSize) + return ERROR(corruption_detected); + + if (HUF_isError( + (litEncType == set_repeat) + ? (singleStream ? HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr) + : HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr)) + : (singleStream + ? HUF_decompress1X2_DCtx_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize, + dctx->entropy.workspace, sizeof(dctx->entropy.workspace)) + : HUF_decompress4X_hufOnly_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize, + dctx->entropy.workspace, sizeof(dctx->entropy.workspace))))) + return ERROR(corruption_detected); + + dctx->litPtr = dctx->litBuffer; + dctx->litSize = litSize; + dctx->litEntropy = 1; + if (litEncType == set_compressed) + dctx->HUFptr = dctx->entropy.hufTable; + memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); + return litCSize + lhSize; + } + + case set_basic: { + size_t litSize, lhSize; + U32 const lhlCode = ((istart[0]) >> 2) & 3; + switch (lhlCode) { + case 0: + case 2: + default: /* note : default is impossible, since lhlCode into [0..3] */ + lhSize = 1; + litSize = istart[0] >> 3; + break; + case 1: + lhSize = 2; + litSize = ZSTD_readLE16(istart) >> 4; + break; + case 3: + lhSize = 3; + litSize = ZSTD_readLE24(istart) >> 4; + break; + } + + if (lhSize + litSize + WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */ + if (litSize + lhSize > srcSize) + return ERROR(corruption_detected); + memcpy(dctx->litBuffer, istart + lhSize, litSize); + dctx->litPtr = dctx->litBuffer; + dctx->litSize = litSize; + memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); + return lhSize + litSize; + } + /* direct reference into compressed stream */ + dctx->litPtr = istart + lhSize; + dctx->litSize = litSize; + return lhSize + litSize; + } + + case set_rle: { + U32 const lhlCode = ((istart[0]) >> 2) & 3; + size_t litSize, lhSize; + switch (lhlCode) { + case 0: + case 2: + default: /* note : default is impossible, since lhlCode into [0..3] */ + lhSize = 1; + litSize = istart[0] >> 3; + break; + case 1: + lhSize = 2; + litSize = ZSTD_readLE16(istart) >> 4; + break; + case 3: + lhSize = 3; + litSize = ZSTD_readLE24(istart) >> 4; + if (srcSize < 4) + return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */ + break; + } + if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) + return ERROR(corruption_detected); + memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH); + dctx->litPtr = dctx->litBuffer; + dctx->litSize = litSize; + return lhSize + 1; + } + default: + return ERROR(corruption_detected); /* impossible */ + } + } +} + +typedef union { + FSE_decode_t realData; + U32 alignedBy4; +} FSE_decode_t4; + +static const FSE_decode_t4 LL_defaultDTable[(1 << LL_DEFAULTNORMLOG) + 1] = { + {{LL_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ + {{0, 0, 4}}, /* 0 : base, symbol, bits */ + {{16, 0, 4}}, + {{32, 1, 5}}, + {{0, 3, 5}}, + {{0, 4, 5}}, + {{0, 6, 5}}, + {{0, 7, 5}}, + {{0, 9, 5}}, + {{0, 10, 5}}, + {{0, 12, 5}}, + {{0, 14, 6}}, + {{0, 16, 5}}, + {{0, 18, 5}}, + {{0, 19, 5}}, + {{0, 21, 5}}, + {{0, 22, 5}}, + {{0, 24, 5}}, + {{32, 25, 5}}, + {{0, 26, 5}}, + {{0, 27, 6}}, + {{0, 29, 6}}, + {{0, 31, 6}}, + {{32, 0, 4}}, + {{0, 1, 4}}, + {{0, 2, 5}}, + {{32, 4, 5}}, + {{0, 5, 5}}, + {{32, 7, 5}}, + {{0, 8, 5}}, + {{32, 10, 5}}, + {{0, 11, 5}}, + {{0, 13, 6}}, + {{32, 16, 5}}, + {{0, 17, 5}}, + {{32, 19, 5}}, + {{0, 20, 5}}, + {{32, 22, 5}}, + {{0, 23, 5}}, + {{0, 25, 4}}, + {{16, 25, 4}}, + {{32, 26, 5}}, + {{0, 28, 6}}, + {{0, 30, 6}}, + {{48, 0, 4}}, + {{16, 1, 4}}, + {{32, 2, 5}}, + {{32, 3, 5}}, + {{32, 5, 5}}, + {{32, 6, 5}}, + {{32, 8, 5}}, + {{32, 9, 5}}, + {{32, 11, 5}}, + {{32, 12, 5}}, + {{0, 15, 6}}, + {{32, 17, 5}}, + {{32, 18, 5}}, + {{32, 20, 5}}, + {{32, 21, 5}}, + {{32, 23, 5}}, + {{32, 24, 5}}, + {{0, 35, 6}}, + {{0, 34, 6}}, + {{0, 33, 6}}, + {{0, 32, 6}}, +}; /* LL_defaultDTable */ + +static const FSE_decode_t4 ML_defaultDTable[(1 << ML_DEFAULTNORMLOG) + 1] = { + {{ML_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ + {{0, 0, 6}}, /* 0 : base, symbol, bits */ + {{0, 1, 4}}, + {{32, 2, 5}}, + {{0, 3, 5}}, + {{0, 5, 5}}, + {{0, 6, 5}}, + {{0, 8, 5}}, + {{0, 10, 6}}, + {{0, 13, 6}}, + {{0, 16, 6}}, + {{0, 19, 6}}, + {{0, 22, 6}}, + {{0, 25, 6}}, + {{0, 28, 6}}, + {{0, 31, 6}}, + {{0, 33, 6}}, + {{0, 35, 6}}, + {{0, 37, 6}}, + {{0, 39, 6}}, + {{0, 41, 6}}, + {{0, 43, 6}}, + {{0, 45, 6}}, + {{16, 1, 4}}, + {{0, 2, 4}}, + {{32, 3, 5}}, + {{0, 4, 5}}, + {{32, 6, 5}}, + {{0, 7, 5}}, + {{0, 9, 6}}, + {{0, 12, 6}}, + {{0, 15, 6}}, + {{0, 18, 6}}, + {{0, 21, 6}}, + {{0, 24, 6}}, + {{0, 27, 6}}, + {{0, 30, 6}}, + {{0, 32, 6}}, + {{0, 34, 6}}, + {{0, 36, 6}}, + {{0, 38, 6}}, + {{0, 40, 6}}, + {{0, 42, 6}}, + {{0, 44, 6}}, + {{32, 1, 4}}, + {{48, 1, 4}}, + {{16, 2, 4}}, + {{32, 4, 5}}, + {{32, 5, 5}}, + {{32, 7, 5}}, + {{32, 8, 5}}, + {{0, 11, 6}}, + {{0, 14, 6}}, + {{0, 17, 6}}, + {{0, 20, 6}}, + {{0, 23, 6}}, + {{0, 26, 6}}, + {{0, 29, 6}}, + {{0, 52, 6}}, + {{0, 51, 6}}, + {{0, 50, 6}}, + {{0, 49, 6}}, + {{0, 48, 6}}, + {{0, 47, 6}}, + {{0, 46, 6}}, +}; /* ML_defaultDTable */ + +static const FSE_decode_t4 OF_defaultDTable[(1 << OF_DEFAULTNORMLOG) + 1] = { + {{OF_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ + {{0, 0, 5}}, /* 0 : base, symbol, bits */ + {{0, 6, 4}}, + {{0, 9, 5}}, + {{0, 15, 5}}, + {{0, 21, 5}}, + {{0, 3, 5}}, + {{0, 7, 4}}, + {{0, 12, 5}}, + {{0, 18, 5}}, + {{0, 23, 5}}, + {{0, 5, 5}}, + {{0, 8, 4}}, + {{0, 14, 5}}, + {{0, 20, 5}}, + {{0, 2, 5}}, + {{16, 7, 4}}, + {{0, 11, 5}}, + {{0, 17, 5}}, + {{0, 22, 5}}, + {{0, 4, 5}}, + {{16, 8, 4}}, + {{0, 13, 5}}, + {{0, 19, 5}}, + {{0, 1, 5}}, + {{16, 6, 4}}, + {{0, 10, 5}}, + {{0, 16, 5}}, + {{0, 28, 5}}, + {{0, 27, 5}}, + {{0, 26, 5}}, + {{0, 25, 5}}, + {{0, 24, 5}}, +}; /* OF_defaultDTable */ + +/*! ZSTD_buildSeqTable() : + @return : nb bytes read from src, + or an error code if it fails, testable with ZSTD_isError() +*/ +static size_t ZSTD_buildSeqTable(FSE_DTable *DTableSpace, const FSE_DTable **DTablePtr, symbolEncodingType_e type, U32 max, U32 maxLog, const void *src, + size_t srcSize, const FSE_decode_t4 *defaultTable, U32 flagRepeatTable, void *workspace, size_t workspaceSize) +{ + const void *const tmpPtr = defaultTable; /* bypass strict aliasing */ + switch (type) { + case set_rle: + if (!srcSize) + return ERROR(srcSize_wrong); + if ((*(const BYTE *)src) > max) + return ERROR(corruption_detected); + FSE_buildDTable_rle(DTableSpace, *(const BYTE *)src); + *DTablePtr = DTableSpace; + return 1; + case set_basic: *DTablePtr = (const FSE_DTable *)tmpPtr; return 0; + case set_repeat: + if (!flagRepeatTable) + return ERROR(corruption_detected); + return 0; + default: /* impossible */ + case set_compressed: { + U32 tableLog; + S16 *norm = (S16 *)workspace; + size_t const spaceUsed32 = ALIGN(sizeof(S16) * (MaxSeq + 1), sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(GENERIC); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + { + size_t const headerSize = FSE_readNCount(norm, &max, &tableLog, src, srcSize); + if (FSE_isError(headerSize)) + return ERROR(corruption_detected); + if (tableLog > maxLog) + return ERROR(corruption_detected); + FSE_buildDTable_wksp(DTableSpace, norm, max, tableLog, workspace, workspaceSize); + *DTablePtr = DTableSpace; + return headerSize; + } + } + } +} + +size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx *dctx, int *nbSeqPtr, const void *src, size_t srcSize) +{ + const BYTE *const istart = (const BYTE *const)src; + const BYTE *const iend = istart + srcSize; + const BYTE *ip = istart; + + /* check */ + if (srcSize < MIN_SEQUENCES_SIZE) + return ERROR(srcSize_wrong); + + /* SeqHead */ + { + int nbSeq = *ip++; + if (!nbSeq) { + *nbSeqPtr = 0; + return 1; + } + if (nbSeq > 0x7F) { + if (nbSeq == 0xFF) { + if (ip + 2 > iend) + return ERROR(srcSize_wrong); + nbSeq = ZSTD_readLE16(ip) + LONGNBSEQ, ip += 2; + } else { + if (ip >= iend) + return ERROR(srcSize_wrong); + nbSeq = ((nbSeq - 0x80) << 8) + *ip++; + } + } + *nbSeqPtr = nbSeq; + } + + /* FSE table descriptors */ + if (ip + 4 > iend) + return ERROR(srcSize_wrong); /* minimum possible size */ + { + symbolEncodingType_e const LLtype = (symbolEncodingType_e)(*ip >> 6); + symbolEncodingType_e const OFtype = (symbolEncodingType_e)((*ip >> 4) & 3); + symbolEncodingType_e const MLtype = (symbolEncodingType_e)((*ip >> 2) & 3); + ip++; + + /* Build DTables */ + { + size_t const llhSize = ZSTD_buildSeqTable(dctx->entropy.LLTable, &dctx->LLTptr, LLtype, MaxLL, LLFSELog, ip, iend - ip, + LL_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); + if (ZSTD_isError(llhSize)) + return ERROR(corruption_detected); + ip += llhSize; + } + { + size_t const ofhSize = ZSTD_buildSeqTable(dctx->entropy.OFTable, &dctx->OFTptr, OFtype, MaxOff, OffFSELog, ip, iend - ip, + OF_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); + if (ZSTD_isError(ofhSize)) + return ERROR(corruption_detected); + ip += ofhSize; + } + { + size_t const mlhSize = ZSTD_buildSeqTable(dctx->entropy.MLTable, &dctx->MLTptr, MLtype, MaxML, MLFSELog, ip, iend - ip, + ML_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); + if (ZSTD_isError(mlhSize)) + return ERROR(corruption_detected); + ip += mlhSize; + } + } + + return ip - istart; +} + +typedef struct { + size_t litLength; + size_t matchLength; + size_t offset; + const BYTE *match; +} seq_t; + +typedef struct { + BIT_DStream_t DStream; + FSE_DState_t stateLL; + FSE_DState_t stateOffb; + FSE_DState_t stateML; + size_t prevOffset[ZSTD_REP_NUM]; + const BYTE *base; + size_t pos; + uPtrDiff gotoDict; +} seqState_t; + +FORCE_NOINLINE +size_t ZSTD_execSequenceLast7(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, + const BYTE *const vBase, const BYTE *const dictEnd) +{ + BYTE *const oLitEnd = op + sequence.litLength; + size_t const sequenceLength = sequence.litLength + sequence.matchLength; + BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ + BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; + const BYTE *const iLitEnd = *litPtr + sequence.litLength; + const BYTE *match = oLitEnd - sequence.offset; + + /* check */ + if (oMatchEnd > oend) + return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ + if (iLitEnd > litLimit) + return ERROR(corruption_detected); /* over-read beyond lit buffer */ + if (oLitEnd <= oend_w) + return ERROR(GENERIC); /* Precondition */ + + /* copy literals */ + if (op < oend_w) { + ZSTD_wildcopy(op, *litPtr, oend_w - op); + *litPtr += oend_w - op; + op = oend_w; + } + while (op < oLitEnd) + *op++ = *(*litPtr)++; + + /* copy Match */ + if (sequence.offset > (size_t)(oLitEnd - base)) { + /* offset beyond prefix */ + if (sequence.offset > (size_t)(oLitEnd - vBase)) + return ERROR(corruption_detected); + match = dictEnd - (base - match); + if (match + sequence.matchLength <= dictEnd) { + memmove(oLitEnd, match, sequence.matchLength); + return sequenceLength; + } + /* span extDict & currPrefixSegment */ + { + size_t const length1 = dictEnd - match; + memmove(oLitEnd, match, length1); + op = oLitEnd + length1; + sequence.matchLength -= length1; + match = base; + } + } + while (op < oMatchEnd) + *op++ = *match++; + return sequenceLength; +} + +static seq_t ZSTD_decodeSequence(seqState_t *seqState) +{ + seq_t seq; + + U32 const llCode = FSE_peekSymbol(&seqState->stateLL); + U32 const mlCode = FSE_peekSymbol(&seqState->stateML); + U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ + + U32 const llBits = LL_bits[llCode]; + U32 const mlBits = ML_bits[mlCode]; + U32 const ofBits = ofCode; + U32 const totalBits = llBits + mlBits + ofBits; + + static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, + 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000}; + + static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, + 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41, + 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003}; + + static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD, + 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, + 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD}; + + /* sequence */ + { + size_t offset; + if (!ofCode) + offset = 0; + else { + offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); + } + + if (ofCode <= 1) { + offset += (llCode == 0); + if (offset) { + size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; + temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ + if (offset != 1) + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset = temp; + } else { + offset = seqState->prevOffset[0]; + } + } else { + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset; + } + seq.offset = offset; + } + + seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() && (mlBits + llBits > 24)) + BIT_reloadDStream(&seqState->DStream); + + seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) + BIT_reloadDStream(&seqState->DStream); + + /* ANS state update */ + FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ + FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ + FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ + + seq.match = NULL; + + return seq; +} + +FORCE_INLINE +size_t ZSTD_execSequence(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, + const BYTE *const vBase, const BYTE *const dictEnd) +{ + BYTE *const oLitEnd = op + sequence.litLength; + size_t const sequenceLength = sequence.litLength + sequence.matchLength; + BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ + BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; + const BYTE *const iLitEnd = *litPtr + sequence.litLength; + const BYTE *match = oLitEnd - sequence.offset; + + /* check */ + if (oMatchEnd > oend) + return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ + if (iLitEnd > litLimit) + return ERROR(corruption_detected); /* over-read beyond lit buffer */ + if (oLitEnd > oend_w) + return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); + + /* copy Literals */ + ZSTD_copy8(op, *litPtr); + if (sequence.litLength > 8) + ZSTD_wildcopy(op + 8, (*litPtr) + 8, + sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ + op = oLitEnd; + *litPtr = iLitEnd; /* update for next sequence */ + + /* copy Match */ + if (sequence.offset > (size_t)(oLitEnd - base)) { + /* offset beyond prefix */ + if (sequence.offset > (size_t)(oLitEnd - vBase)) + return ERROR(corruption_detected); + match = dictEnd + (match - base); + if (match + sequence.matchLength <= dictEnd) { + memmove(oLitEnd, match, sequence.matchLength); + return sequenceLength; + } + /* span extDict & currPrefixSegment */ + { + size_t const length1 = dictEnd - match; + memmove(oLitEnd, match, length1); + op = oLitEnd + length1; + sequence.matchLength -= length1; + match = base; + if (op > oend_w || sequence.matchLength < MINMATCH) { + U32 i; + for (i = 0; i < sequence.matchLength; ++i) + op[i] = match[i]; + return sequenceLength; + } + } + } + /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */ + + /* match within prefix */ + if (sequence.offset < 8) { + /* close range match, overlap */ + static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ + static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */ + int const sub2 = dec64table[sequence.offset]; + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += dec32table[sequence.offset]; + ZSTD_copy4(op + 4, match); + match -= sub2; + } else { + ZSTD_copy8(op, match); + } + op += 8; + match += 8; + + if (oMatchEnd > oend - (16 - MINMATCH)) { + if (op < oend_w) { + ZSTD_wildcopy(op, match, oend_w - op); + match += oend_w - op; + op = oend_w; + } + while (op < oMatchEnd) + *op++ = *match++; + } else { + ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */ + } + return sequenceLength; +} + +static size_t ZSTD_decompressSequences(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize) +{ + const BYTE *ip = (const BYTE *)seqStart; + const BYTE *const iend = ip + seqSize; + BYTE *const ostart = (BYTE * const)dst; + BYTE *const oend = ostart + maxDstSize; + BYTE *op = ostart; + const BYTE *litPtr = dctx->litPtr; + const BYTE *const litEnd = litPtr + dctx->litSize; + const BYTE *const base = (const BYTE *)(dctx->base); + const BYTE *const vBase = (const BYTE *)(dctx->vBase); + const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd); + int nbSeq; + + /* Build Decoding Tables */ + { + size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); + if (ZSTD_isError(seqHSize)) + return seqHSize; + ip += seqHSize; + } + + /* Regen sequences */ + if (nbSeq) { + seqState_t seqState; + dctx->fseEntropy = 1; + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + seqState.prevOffset[i] = dctx->entropy.rep[i]; + } + CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected); + FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); + FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); + FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); + + for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq;) { + nbSeq--; + { + seq_t const sequence = ZSTD_decodeSequence(&seqState); + size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd); + if (ZSTD_isError(oneSeqSize)) + return oneSeqSize; + op += oneSeqSize; + } + } + + /* check if reached exact end */ + if (nbSeq) + return ERROR(corruption_detected); + /* save reps for next block */ + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); + } + } + + /* last literal segment */ + { + size_t const lastLLSize = litEnd - litPtr; + if (lastLLSize > (size_t)(oend - op)) + return ERROR(dstSize_tooSmall); + memcpy(op, litPtr, lastLLSize); + op += lastLLSize; + } + + return op - ostart; +} + +FORCE_INLINE seq_t ZSTD_decodeSequenceLong_generic(seqState_t *seqState, int const longOffsets) +{ + seq_t seq; + + U32 const llCode = FSE_peekSymbol(&seqState->stateLL); + U32 const mlCode = FSE_peekSymbol(&seqState->stateML); + U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ + + U32 const llBits = LL_bits[llCode]; + U32 const mlBits = ML_bits[mlCode]; + U32 const ofBits = ofCode; + U32 const totalBits = llBits + mlBits + ofBits; + + static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, + 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000}; + + static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, + 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41, + 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003}; + + static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD, + 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, + 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD}; + + /* sequence */ + { + size_t offset; + if (!ofCode) + offset = 0; + else { + if (longOffsets) { + int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN); + offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits); + if (ZSTD_32bits() || extraBits) + BIT_reloadDStream(&seqState->DStream); + if (extraBits) + offset += BIT_readBitsFast(&seqState->DStream, extraBits); + } else { + offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); + } + } + + if (ofCode <= 1) { + offset += (llCode == 0); + if (offset) { + size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; + temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ + if (offset != 1) + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset = temp; + } else { + offset = seqState->prevOffset[0]; + } + } else { + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset; + } + seq.offset = offset; + } + + seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() && (mlBits + llBits > 24)) + BIT_reloadDStream(&seqState->DStream); + + seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) + BIT_reloadDStream(&seqState->DStream); + + { + size_t const pos = seqState->pos + seq.litLength; + seq.match = seqState->base + pos - seq.offset; /* single memory segment */ + if (seq.offset > pos) + seq.match += seqState->gotoDict; /* separate memory segment */ + seqState->pos = pos + seq.matchLength; + } + + /* ANS state update */ + FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ + FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ + FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ + + return seq; +} + +static seq_t ZSTD_decodeSequenceLong(seqState_t *seqState, unsigned const windowSize) +{ + if (ZSTD_highbit32(windowSize) > STREAM_ACCUMULATOR_MIN) { + return ZSTD_decodeSequenceLong_generic(seqState, 1); + } else { + return ZSTD_decodeSequenceLong_generic(seqState, 0); + } +} + +FORCE_INLINE +size_t ZSTD_execSequenceLong(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, + const BYTE *const vBase, const BYTE *const dictEnd) +{ + BYTE *const oLitEnd = op + sequence.litLength; + size_t const sequenceLength = sequence.litLength + sequence.matchLength; + BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ + BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; + const BYTE *const iLitEnd = *litPtr + sequence.litLength; + const BYTE *match = sequence.match; + + /* check */ + if (oMatchEnd > oend) + return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ + if (iLitEnd > litLimit) + return ERROR(corruption_detected); /* over-read beyond lit buffer */ + if (oLitEnd > oend_w) + return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); + + /* copy Literals */ + ZSTD_copy8(op, *litPtr); + if (sequence.litLength > 8) + ZSTD_wildcopy(op + 8, (*litPtr) + 8, + sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ + op = oLitEnd; + *litPtr = iLitEnd; /* update for next sequence */ + + /* copy Match */ + if (sequence.offset > (size_t)(oLitEnd - base)) { + /* offset beyond prefix */ + if (sequence.offset > (size_t)(oLitEnd - vBase)) + return ERROR(corruption_detected); + if (match + sequence.matchLength <= dictEnd) { + memmove(oLitEnd, match, sequence.matchLength); + return sequenceLength; + } + /* span extDict & currPrefixSegment */ + { + size_t const length1 = dictEnd - match; + memmove(oLitEnd, match, length1); + op = oLitEnd + length1; + sequence.matchLength -= length1; + match = base; + if (op > oend_w || sequence.matchLength < MINMATCH) { + U32 i; + for (i = 0; i < sequence.matchLength; ++i) + op[i] = match[i]; + return sequenceLength; + } + } + } + /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */ + + /* match within prefix */ + if (sequence.offset < 8) { + /* close range match, overlap */ + static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ + static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */ + int const sub2 = dec64table[sequence.offset]; + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += dec32table[sequence.offset]; + ZSTD_copy4(op + 4, match); + match -= sub2; + } else { + ZSTD_copy8(op, match); + } + op += 8; + match += 8; + + if (oMatchEnd > oend - (16 - MINMATCH)) { + if (op < oend_w) { + ZSTD_wildcopy(op, match, oend_w - op); + match += oend_w - op; + op = oend_w; + } + while (op < oMatchEnd) + *op++ = *match++; + } else { + ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */ + } + return sequenceLength; +} + +static size_t ZSTD_decompressSequencesLong(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize) +{ + const BYTE *ip = (const BYTE *)seqStart; + const BYTE *const iend = ip + seqSize; + BYTE *const ostart = (BYTE * const)dst; + BYTE *const oend = ostart + maxDstSize; + BYTE *op = ostart; + const BYTE *litPtr = dctx->litPtr; + const BYTE *const litEnd = litPtr + dctx->litSize; + const BYTE *const base = (const BYTE *)(dctx->base); + const BYTE *const vBase = (const BYTE *)(dctx->vBase); + const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd); + unsigned const windowSize = dctx->fParams.windowSize; + int nbSeq; + + /* Build Decoding Tables */ + { + size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); + if (ZSTD_isError(seqHSize)) + return seqHSize; + ip += seqHSize; + } + + /* Regen sequences */ + if (nbSeq) { +#define STORED_SEQS 4 +#define STOSEQ_MASK (STORED_SEQS - 1) +#define ADVANCED_SEQS 4 + seq_t *sequences = (seq_t *)dctx->entropy.workspace; + int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS); + seqState_t seqState; + int seqNb; + ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.workspace) >= sizeof(seq_t) * STORED_SEQS); + dctx->fseEntropy = 1; + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + seqState.prevOffset[i] = dctx->entropy.rep[i]; + } + seqState.base = base; + seqState.pos = (size_t)(op - base); + seqState.gotoDict = (uPtrDiff)dictEnd - (uPtrDiff)base; /* cast to avoid undefined behaviour */ + CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected); + FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); + FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); + FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); + + /* prepare in advance */ + for (seqNb = 0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNb < seqAdvance; seqNb++) { + sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize); + } + if (seqNb < seqAdvance) + return ERROR(corruption_detected); + + /* decode and decompress */ + for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb < nbSeq; seqNb++) { + seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize); + size_t const oneSeqSize = + ZSTD_execSequenceLong(op, oend, sequences[(seqNb - ADVANCED_SEQS) & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); + if (ZSTD_isError(oneSeqSize)) + return oneSeqSize; + ZSTD_PREFETCH(sequence.match); + sequences[seqNb & STOSEQ_MASK] = sequence; + op += oneSeqSize; + } + if (seqNb < nbSeq) + return ERROR(corruption_detected); + + /* finish queue */ + seqNb -= seqAdvance; + for (; seqNb < nbSeq; seqNb++) { + size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[seqNb & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); + if (ZSTD_isError(oneSeqSize)) + return oneSeqSize; + op += oneSeqSize; + } + + /* save reps for next block */ + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); + } + } + + /* last literal segment */ + { + size_t const lastLLSize = litEnd - litPtr; + if (lastLLSize > (size_t)(oend - op)) + return ERROR(dstSize_tooSmall); + memcpy(op, litPtr, lastLLSize); + op += lastLLSize; + } + + return op - ostart; +} + +static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ /* blockType == blockCompressed */ + const BYTE *ip = (const BYTE *)src; + + if (srcSize >= ZSTD_BLOCKSIZE_ABSOLUTEMAX) + return ERROR(srcSize_wrong); + + /* Decode literals section */ + { + size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize); + if (ZSTD_isError(litCSize)) + return litCSize; + ip += litCSize; + srcSize -= litCSize; + } + if (sizeof(size_t) > 4) /* do not enable prefetching on 32-bits x86, as it's performance detrimental */ + /* likely because of register pressure */ + /* if that's the correct cause, then 32-bits ARM should be affected differently */ + /* it would be good to test this on ARM real hardware, to see if prefetch version improves speed */ + if (dctx->fParams.windowSize > (1 << 23)) + return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize); + return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize); +} + +static void ZSTD_checkContinuity(ZSTD_DCtx *dctx, const void *dst) +{ + if (dst != dctx->previousDstEnd) { /* not contiguous */ + dctx->dictEnd = dctx->previousDstEnd; + dctx->vBase = (const char *)dst - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base)); + dctx->base = dst; + dctx->previousDstEnd = dst; + } +} + +size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t dSize; + ZSTD_checkContinuity(dctx, dst); + dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); + dctx->previousDstEnd = (char *)dst + dSize; + return dSize; +} + +/** ZSTD_insertBlock() : + insert `src` block into `dctx` history. Useful to track uncompressed blocks. */ +size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart, size_t blockSize) +{ + ZSTD_checkContinuity(dctx, blockStart); + dctx->previousDstEnd = (const char *)blockStart + blockSize; + return blockSize; +} + +size_t ZSTD_generateNxBytes(void *dst, size_t dstCapacity, BYTE byte, size_t length) +{ + if (length > dstCapacity) + return ERROR(dstSize_tooSmall); + memset(dst, byte, length); + return length; +} + +/** ZSTD_findFrameCompressedSize() : + * compatible with legacy mode + * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame + * `srcSize` must be at least as large as the frame contained + * @return : the compressed size of the frame starting at `src` */ +size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize) +{ + if (srcSize >= ZSTD_skippableHeaderSize && (ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + return ZSTD_skippableHeaderSize + ZSTD_readLE32((const BYTE *)src + 4); + } else { + const BYTE *ip = (const BYTE *)src; + const BYTE *const ipstart = ip; + size_t remainingSize = srcSize; + ZSTD_frameParams fParams; + + size_t const headerSize = ZSTD_frameHeaderSize(ip, remainingSize); + if (ZSTD_isError(headerSize)) + return headerSize; + + /* Frame Header */ + { + size_t const ret = ZSTD_getFrameParams(&fParams, ip, remainingSize); + if (ZSTD_isError(ret)) + return ret; + if (ret > 0) + return ERROR(srcSize_wrong); + } + + ip += headerSize; + remainingSize -= headerSize; + + /* Loop on each block */ + while (1) { + blockProperties_t blockProperties; + size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); + if (ZSTD_isError(cBlockSize)) + return cBlockSize; + + if (ZSTD_blockHeaderSize + cBlockSize > remainingSize) + return ERROR(srcSize_wrong); + + ip += ZSTD_blockHeaderSize + cBlockSize; + remainingSize -= ZSTD_blockHeaderSize + cBlockSize; + + if (blockProperties.lastBlock) + break; + } + + if (fParams.checksumFlag) { /* Frame content checksum */ + if (remainingSize < 4) + return ERROR(srcSize_wrong); + ip += 4; + remainingSize -= 4; + } + + return ip - ipstart; + } +} + +/*! ZSTD_decompressFrame() : +* @dctx must be properly initialized */ +static size_t ZSTD_decompressFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void **srcPtr, size_t *srcSizePtr) +{ + const BYTE *ip = (const BYTE *)(*srcPtr); + BYTE *const ostart = (BYTE * const)dst; + BYTE *const oend = ostart + dstCapacity; + BYTE *op = ostart; + size_t remainingSize = *srcSizePtr; + + /* check */ + if (remainingSize < ZSTD_frameHeaderSize_min + ZSTD_blockHeaderSize) + return ERROR(srcSize_wrong); + + /* Frame Header */ + { + size_t const frameHeaderSize = ZSTD_frameHeaderSize(ip, ZSTD_frameHeaderSize_prefix); + if (ZSTD_isError(frameHeaderSize)) + return frameHeaderSize; + if (remainingSize < frameHeaderSize + ZSTD_blockHeaderSize) + return ERROR(srcSize_wrong); + CHECK_F(ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize)); + ip += frameHeaderSize; + remainingSize -= frameHeaderSize; + } + + /* Loop on each block */ + while (1) { + size_t decodedSize; + blockProperties_t blockProperties; + size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); + if (ZSTD_isError(cBlockSize)) + return cBlockSize; + + ip += ZSTD_blockHeaderSize; + remainingSize -= ZSTD_blockHeaderSize; + if (cBlockSize > remainingSize) + return ERROR(srcSize_wrong); + + switch (blockProperties.blockType) { + case bt_compressed: decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend - op, ip, cBlockSize); break; + case bt_raw: decodedSize = ZSTD_copyRawBlock(op, oend - op, ip, cBlockSize); break; + case bt_rle: decodedSize = ZSTD_generateNxBytes(op, oend - op, *ip, blockProperties.origSize); break; + case bt_reserved: + default: return ERROR(corruption_detected); + } + + if (ZSTD_isError(decodedSize)) + return decodedSize; + if (dctx->fParams.checksumFlag) + xxh64_update(&dctx->xxhState, op, decodedSize); + op += decodedSize; + ip += cBlockSize; + remainingSize -= cBlockSize; + if (blockProperties.lastBlock) + break; + } + + if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */ + U32 const checkCalc = (U32)xxh64_digest(&dctx->xxhState); + U32 checkRead; + if (remainingSize < 4) + return ERROR(checksum_wrong); + checkRead = ZSTD_readLE32(ip); + if (checkRead != checkCalc) + return ERROR(checksum_wrong); + ip += 4; + remainingSize -= 4; + } + + /* Allow caller to get size read */ + *srcPtr = ip; + *srcSizePtr = remainingSize; + return op - ostart; +} + +static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict); +static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict); + +static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize, + const ZSTD_DDict *ddict) +{ + void *const dststart = dst; + + if (ddict) { + if (dict) { + /* programmer error, these two cases should be mutually exclusive */ + return ERROR(GENERIC); + } + + dict = ZSTD_DDictDictContent(ddict); + dictSize = ZSTD_DDictDictSize(ddict); + } + + while (srcSize >= ZSTD_frameHeaderSize_prefix) { + U32 magicNumber; + + magicNumber = ZSTD_readLE32(src); + if (magicNumber != ZSTD_MAGICNUMBER) { + if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + size_t skippableSize; + if (srcSize < ZSTD_skippableHeaderSize) + return ERROR(srcSize_wrong); + skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize; + if (srcSize < skippableSize) { + return ERROR(srcSize_wrong); + } + + src = (const BYTE *)src + skippableSize; + srcSize -= skippableSize; + continue; + } else { + return ERROR(prefix_unknown); + } + } + + if (ddict) { + /* we were called from ZSTD_decompress_usingDDict */ + ZSTD_refDDict(dctx, ddict); + } else { + /* this will initialize correctly with no dict if dict == NULL, so + * use this in all cases but ddict */ + CHECK_F(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize)); + } + ZSTD_checkContinuity(dctx, dst); + + { + const size_t res = ZSTD_decompressFrame(dctx, dst, dstCapacity, &src, &srcSize); + if (ZSTD_isError(res)) + return res; + /* don't need to bounds check this, ZSTD_decompressFrame will have + * already */ + dst = (BYTE *)dst + res; + dstCapacity -= res; + } + } + + if (srcSize) + return ERROR(srcSize_wrong); /* input not entirely consumed */ + + return (BYTE *)dst - (BYTE *)dststart; +} + +size_t ZSTD_decompress_usingDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize) +{ + return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, dict, dictSize, NULL); +} + +size_t ZSTD_decompressDCtx(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + return ZSTD_decompress_usingDict(dctx, dst, dstCapacity, src, srcSize, NULL, 0); +} + +/*-************************************** +* Advanced Streaming Decompression API +* Bufferless and synchronous +****************************************/ +size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx) { return dctx->expected; } + +ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx) +{ + switch (dctx->stage) { + default: /* should not happen */ + case ZSTDds_getFrameHeaderSize: + case ZSTDds_decodeFrameHeader: return ZSTDnit_frameHeader; + case ZSTDds_decodeBlockHeader: return ZSTDnit_blockHeader; + case ZSTDds_decompressBlock: return ZSTDnit_block; + case ZSTDds_decompressLastBlock: return ZSTDnit_lastBlock; + case ZSTDds_checkChecksum: return ZSTDnit_checksum; + case ZSTDds_decodeSkippableHeader: + case ZSTDds_skipFrame: return ZSTDnit_skippableFrame; + } +} + +int ZSTD_isSkipFrame(ZSTD_DCtx *dctx) { return dctx->stage == ZSTDds_skipFrame; } /* for zbuff */ + +/** ZSTD_decompressContinue() : +* @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity) +* or an error code, which can be tested using ZSTD_isError() */ +size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + /* Sanity check */ + if (srcSize != dctx->expected) + return ERROR(srcSize_wrong); + if (dstCapacity) + ZSTD_checkContinuity(dctx, dst); + + switch (dctx->stage) { + case ZSTDds_getFrameHeaderSize: + if (srcSize != ZSTD_frameHeaderSize_prefix) + return ERROR(srcSize_wrong); /* impossible */ + if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ + memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); + dctx->expected = ZSTD_skippableHeaderSize - ZSTD_frameHeaderSize_prefix; /* magic number + skippable frame length */ + dctx->stage = ZSTDds_decodeSkippableHeader; + return 0; + } + dctx->headerSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_prefix); + if (ZSTD_isError(dctx->headerSize)) + return dctx->headerSize; + memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); + if (dctx->headerSize > ZSTD_frameHeaderSize_prefix) { + dctx->expected = dctx->headerSize - ZSTD_frameHeaderSize_prefix; + dctx->stage = ZSTDds_decodeFrameHeader; + return 0; + } + dctx->expected = 0; /* not necessary to copy more */ + + case ZSTDds_decodeFrameHeader: + memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); + CHECK_F(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize)); + dctx->expected = ZSTD_blockHeaderSize; + dctx->stage = ZSTDds_decodeBlockHeader; + return 0; + + case ZSTDds_decodeBlockHeader: { + blockProperties_t bp; + size_t const cBlockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp); + if (ZSTD_isError(cBlockSize)) + return cBlockSize; + dctx->expected = cBlockSize; + dctx->bType = bp.blockType; + dctx->rleSize = bp.origSize; + if (cBlockSize) { + dctx->stage = bp.lastBlock ? ZSTDds_decompressLastBlock : ZSTDds_decompressBlock; + return 0; + } + /* empty block */ + if (bp.lastBlock) { + if (dctx->fParams.checksumFlag) { + dctx->expected = 4; + dctx->stage = ZSTDds_checkChecksum; + } else { + dctx->expected = 0; /* end of frame */ + dctx->stage = ZSTDds_getFrameHeaderSize; + } + } else { + dctx->expected = 3; /* go directly to next header */ + dctx->stage = ZSTDds_decodeBlockHeader; + } + return 0; + } + case ZSTDds_decompressLastBlock: + case ZSTDds_decompressBlock: { + size_t rSize; + switch (dctx->bType) { + case bt_compressed: rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); break; + case bt_raw: rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize); break; + case bt_rle: rSize = ZSTD_setRleBlock(dst, dstCapacity, src, srcSize, dctx->rleSize); break; + case bt_reserved: /* should never happen */ + default: return ERROR(corruption_detected); + } + if (ZSTD_isError(rSize)) + return rSize; + if (dctx->fParams.checksumFlag) + xxh64_update(&dctx->xxhState, dst, rSize); + + if (dctx->stage == ZSTDds_decompressLastBlock) { /* end of frame */ + if (dctx->fParams.checksumFlag) { /* another round for frame checksum */ + dctx->expected = 4; + dctx->stage = ZSTDds_checkChecksum; + } else { + dctx->expected = 0; /* ends here */ + dctx->stage = ZSTDds_getFrameHeaderSize; + } + } else { + dctx->stage = ZSTDds_decodeBlockHeader; + dctx->expected = ZSTD_blockHeaderSize; + dctx->previousDstEnd = (char *)dst + rSize; + } + return rSize; + } + case ZSTDds_checkChecksum: { + U32 const h32 = (U32)xxh64_digest(&dctx->xxhState); + U32 const check32 = ZSTD_readLE32(src); /* srcSize == 4, guaranteed by dctx->expected */ + if (check32 != h32) + return ERROR(checksum_wrong); + dctx->expected = 0; + dctx->stage = ZSTDds_getFrameHeaderSize; + return 0; + } + case ZSTDds_decodeSkippableHeader: { + memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); + dctx->expected = ZSTD_readLE32(dctx->headerBuffer + 4); + dctx->stage = ZSTDds_skipFrame; + return 0; + } + case ZSTDds_skipFrame: { + dctx->expected = 0; + dctx->stage = ZSTDds_getFrameHeaderSize; + return 0; + } + default: + return ERROR(GENERIC); /* impossible */ + } +} + +static size_t ZSTD_refDictContent(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) +{ + dctx->dictEnd = dctx->previousDstEnd; + dctx->vBase = (const char *)dict - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base)); + dctx->base = dict; + dctx->previousDstEnd = (const char *)dict + dictSize; + return 0; +} + +/* ZSTD_loadEntropy() : + * dict : must point at beginning of a valid zstd dictionary + * @return : size of entropy tables read */ +static size_t ZSTD_loadEntropy(ZSTD_entropyTables_t *entropy, const void *const dict, size_t const dictSize) +{ + const BYTE *dictPtr = (const BYTE *)dict; + const BYTE *const dictEnd = dictPtr + dictSize; + + if (dictSize <= 8) + return ERROR(dictionary_corrupted); + dictPtr += 8; /* skip header = magic + dictID */ + + { + size_t const hSize = HUF_readDTableX4_wksp(entropy->hufTable, dictPtr, dictEnd - dictPtr, entropy->workspace, sizeof(entropy->workspace)); + if (HUF_isError(hSize)) + return ERROR(dictionary_corrupted); + dictPtr += hSize; + } + + { + short offcodeNCount[MaxOff + 1]; + U32 offcodeMaxValue = MaxOff, offcodeLog; + size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(offcodeHeaderSize)) + return ERROR(dictionary_corrupted); + if (offcodeLog > OffFSELog) + return ERROR(dictionary_corrupted); + CHECK_E(FSE_buildDTable_wksp(entropy->OFTable, offcodeNCount, offcodeMaxValue, offcodeLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); + dictPtr += offcodeHeaderSize; + } + + { + short matchlengthNCount[MaxML + 1]; + unsigned matchlengthMaxValue = MaxML, matchlengthLog; + size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(matchlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (matchlengthLog > MLFSELog) + return ERROR(dictionary_corrupted); + CHECK_E(FSE_buildDTable_wksp(entropy->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); + dictPtr += matchlengthHeaderSize; + } + + { + short litlengthNCount[MaxLL + 1]; + unsigned litlengthMaxValue = MaxLL, litlengthLog; + size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(litlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (litlengthLog > LLFSELog) + return ERROR(dictionary_corrupted); + CHECK_E(FSE_buildDTable_wksp(entropy->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); + dictPtr += litlengthHeaderSize; + } + + if (dictPtr + 12 > dictEnd) + return ERROR(dictionary_corrupted); + { + int i; + size_t const dictContentSize = (size_t)(dictEnd - (dictPtr + 12)); + for (i = 0; i < 3; i++) { + U32 const rep = ZSTD_readLE32(dictPtr); + dictPtr += 4; + if (rep == 0 || rep >= dictContentSize) + return ERROR(dictionary_corrupted); + entropy->rep[i] = rep; + } + } + + return dictPtr - (const BYTE *)dict; +} + +static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) +{ + if (dictSize < 8) + return ZSTD_refDictContent(dctx, dict, dictSize); + { + U32 const magic = ZSTD_readLE32(dict); + if (magic != ZSTD_DICT_MAGIC) { + return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */ + } + } + dctx->dictID = ZSTD_readLE32((const char *)dict + 4); + + /* load entropy tables */ + { + size_t const eSize = ZSTD_loadEntropy(&dctx->entropy, dict, dictSize); + if (ZSTD_isError(eSize)) + return ERROR(dictionary_corrupted); + dict = (const char *)dict + eSize; + dictSize -= eSize; + } + dctx->litEntropy = dctx->fseEntropy = 1; + + /* reference dictionary content */ + return ZSTD_refDictContent(dctx, dict, dictSize); +} + +size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) +{ + CHECK_F(ZSTD_decompressBegin(dctx)); + if (dict && dictSize) + CHECK_E(ZSTD_decompress_insertDictionary(dctx, dict, dictSize), dictionary_corrupted); + return 0; +} + +/* ====== ZSTD_DDict ====== */ + +struct ZSTD_DDict_s { + void *dictBuffer; + const void *dictContent; + size_t dictSize; + ZSTD_entropyTables_t entropy; + U32 dictID; + U32 entropyPresent; + ZSTD_customMem cMem; +}; /* typedef'd to ZSTD_DDict within "zstd.h" */ + +size_t ZSTD_DDictWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DDict)); } + +static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict) { return ddict->dictContent; } + +static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict) { return ddict->dictSize; } + +static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict) +{ + ZSTD_decompressBegin(dstDCtx); /* init */ + if (ddict) { /* support refDDict on NULL */ + dstDCtx->dictID = ddict->dictID; + dstDCtx->base = ddict->dictContent; + dstDCtx->vBase = ddict->dictContent; + dstDCtx->dictEnd = (const BYTE *)ddict->dictContent + ddict->dictSize; + dstDCtx->previousDstEnd = dstDCtx->dictEnd; + if (ddict->entropyPresent) { + dstDCtx->litEntropy = 1; + dstDCtx->fseEntropy = 1; + dstDCtx->LLTptr = ddict->entropy.LLTable; + dstDCtx->MLTptr = ddict->entropy.MLTable; + dstDCtx->OFTptr = ddict->entropy.OFTable; + dstDCtx->HUFptr = ddict->entropy.hufTable; + dstDCtx->entropy.rep[0] = ddict->entropy.rep[0]; + dstDCtx->entropy.rep[1] = ddict->entropy.rep[1]; + dstDCtx->entropy.rep[2] = ddict->entropy.rep[2]; + } else { + dstDCtx->litEntropy = 0; + dstDCtx->fseEntropy = 0; + } + } +} + +static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict *ddict) +{ + ddict->dictID = 0; + ddict->entropyPresent = 0; + if (ddict->dictSize < 8) + return 0; + { + U32 const magic = ZSTD_readLE32(ddict->dictContent); + if (magic != ZSTD_DICT_MAGIC) + return 0; /* pure content mode */ + } + ddict->dictID = ZSTD_readLE32((const char *)ddict->dictContent + 4); + + /* load entropy tables */ + CHECK_E(ZSTD_loadEntropy(&ddict->entropy, ddict->dictContent, ddict->dictSize), dictionary_corrupted); + ddict->entropyPresent = 1; + return 0; +} + +static ZSTD_DDict *ZSTD_createDDict_advanced(const void *dict, size_t dictSize, unsigned byReference, ZSTD_customMem customMem) +{ + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + { + ZSTD_DDict *const ddict = (ZSTD_DDict *)ZSTD_malloc(sizeof(ZSTD_DDict), customMem); + if (!ddict) + return NULL; + ddict->cMem = customMem; + + if ((byReference) || (!dict) || (!dictSize)) { + ddict->dictBuffer = NULL; + ddict->dictContent = dict; + } else { + void *const internalBuffer = ZSTD_malloc(dictSize, customMem); + if (!internalBuffer) { + ZSTD_freeDDict(ddict); + return NULL; + } + memcpy(internalBuffer, dict, dictSize); + ddict->dictBuffer = internalBuffer; + ddict->dictContent = internalBuffer; + } + ddict->dictSize = dictSize; + ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ + /* parse dictionary content */ + { + size_t const errorCode = ZSTD_loadEntropy_inDDict(ddict); + if (ZSTD_isError(errorCode)) { + ZSTD_freeDDict(ddict); + return NULL; + } + } + + return ddict; + } +} + +/*! ZSTD_initDDict() : +* Create a digested dictionary, to start decompression without startup delay. +* `dict` content is copied inside DDict. +* Consequently, `dict` can be released after `ZSTD_DDict` creation */ +ZSTD_DDict *ZSTD_initDDict(const void *dict, size_t dictSize, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + return ZSTD_createDDict_advanced(dict, dictSize, 1, stackMem); +} + +size_t ZSTD_freeDDict(ZSTD_DDict *ddict) +{ + if (ddict == NULL) + return 0; /* support free on NULL */ + { + ZSTD_customMem const cMem = ddict->cMem; + ZSTD_free(ddict->dictBuffer, cMem); + ZSTD_free(ddict, cMem); + return 0; + } +} + +/*! ZSTD_getDictID_fromDict() : + * Provides the dictID stored within dictionary. + * if @return == 0, the dictionary is not conformant with Zstandard specification. + * It can still be loaded, but as a content-only dictionary. */ +unsigned ZSTD_getDictID_fromDict(const void *dict, size_t dictSize) +{ + if (dictSize < 8) + return 0; + if (ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC) + return 0; + return ZSTD_readLE32((const char *)dict + 4); +} + +/*! ZSTD_getDictID_fromDDict() : + * Provides the dictID of the dictionary loaded into `ddict`. + * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty. + * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ +unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict) +{ + if (ddict == NULL) + return 0; + return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize); +} + +/*! ZSTD_getDictID_fromFrame() : + * Provides the dictID required to decompressed the frame stored within `src`. + * If @return == 0, the dictID could not be decoded. + * This could for one of the following reasons : + * - The frame does not require a dictionary to be decoded (most common case). + * - The frame was built with dictID intentionally removed. Whatever dictionary is necessary is a hidden information. + * Note : this use case also happens when using a non-conformant dictionary. + * - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`). + * - This is not a Zstandard frame. + * When identifying the exact failure cause, it's possible to used ZSTD_getFrameParams(), which will provide a more precise error code. */ +unsigned ZSTD_getDictID_fromFrame(const void *src, size_t srcSize) +{ + ZSTD_frameParams zfp = {0, 0, 0, 0}; + size_t const hError = ZSTD_getFrameParams(&zfp, src, srcSize); + if (ZSTD_isError(hError)) + return 0; + return zfp.dictID; +} + +/*! ZSTD_decompress_usingDDict() : +* Decompression using a pre-digested Dictionary +* Use dictionary without significant overhead. */ +size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_DDict *ddict) +{ + /* pass content and size in case legacy frames are encountered */ + return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, NULL, 0, ddict); +} + +/*===================================== +* Streaming decompression +*====================================*/ + +typedef enum { zdss_init, zdss_loadHeader, zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage; + +/* *** Resource management *** */ +struct ZSTD_DStream_s { + ZSTD_DCtx *dctx; + ZSTD_DDict *ddictLocal; + const ZSTD_DDict *ddict; + ZSTD_frameParams fParams; + ZSTD_dStreamStage stage; + char *inBuff; + size_t inBuffSize; + size_t inPos; + size_t maxWindowSize; + char *outBuff; + size_t outBuffSize; + size_t outStart; + size_t outEnd; + size_t blockSize; + BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; /* tmp buffer to store frame header */ + size_t lhSize; + ZSTD_customMem customMem; + void *legacyContext; + U32 previousLegacyVersion; + U32 legacyVersion; + U32 hostageByte; +}; /* typedef'd to ZSTD_DStream within "zstd.h" */ + +size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize) +{ + size_t const blockSize = MIN(maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); + size_t const inBuffSize = blockSize; + size_t const outBuffSize = maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; + return ZSTD_DCtxWorkspaceBound() + ZSTD_ALIGN(sizeof(ZSTD_DStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize); +} + +static ZSTD_DStream *ZSTD_createDStream_advanced(ZSTD_customMem customMem) +{ + ZSTD_DStream *zds; + + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + zds = (ZSTD_DStream *)ZSTD_malloc(sizeof(ZSTD_DStream), customMem); + if (zds == NULL) + return NULL; + memset(zds, 0, sizeof(ZSTD_DStream)); + memcpy(&zds->customMem, &customMem, sizeof(ZSTD_customMem)); + zds->dctx = ZSTD_createDCtx_advanced(customMem); + if (zds->dctx == NULL) { + ZSTD_freeDStream(zds); + return NULL; + } + zds->stage = zdss_init; + zds->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT; + return zds; +} + +ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + ZSTD_DStream *zds = ZSTD_createDStream_advanced(stackMem); + if (!zds) { + return NULL; + } + + zds->maxWindowSize = maxWindowSize; + zds->stage = zdss_loadHeader; + zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; + ZSTD_freeDDict(zds->ddictLocal); + zds->ddictLocal = NULL; + zds->ddict = zds->ddictLocal; + zds->legacyVersion = 0; + zds->hostageByte = 0; + + { + size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); + size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; + + zds->inBuff = (char *)ZSTD_malloc(blockSize, zds->customMem); + zds->inBuffSize = blockSize; + zds->outBuff = (char *)ZSTD_malloc(neededOutSize, zds->customMem); + zds->outBuffSize = neededOutSize; + if (zds->inBuff == NULL || zds->outBuff == NULL) { + ZSTD_freeDStream(zds); + return NULL; + } + } + return zds; +} + +ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize, const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize) +{ + ZSTD_DStream *zds = ZSTD_initDStream(maxWindowSize, workspace, workspaceSize); + if (zds) { + zds->ddict = ddict; + } + return zds; +} + +size_t ZSTD_freeDStream(ZSTD_DStream *zds) +{ + if (zds == NULL) + return 0; /* support free on null */ + { + ZSTD_customMem const cMem = zds->customMem; + ZSTD_freeDCtx(zds->dctx); + zds->dctx = NULL; + ZSTD_freeDDict(zds->ddictLocal); + zds->ddictLocal = NULL; + ZSTD_free(zds->inBuff, cMem); + zds->inBuff = NULL; + ZSTD_free(zds->outBuff, cMem); + zds->outBuff = NULL; + ZSTD_free(zds, cMem); + return 0; + } +} + +/* *** Initialization *** */ + +size_t ZSTD_DStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX + ZSTD_blockHeaderSize; } +size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; } + +size_t ZSTD_resetDStream(ZSTD_DStream *zds) +{ + zds->stage = zdss_loadHeader; + zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; + zds->legacyVersion = 0; + zds->hostageByte = 0; + return ZSTD_frameHeaderSize_prefix; +} + +/* ***** Decompression ***** */ + +ZSTD_STATIC size_t ZSTD_limitCopy(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t const length = MIN(dstCapacity, srcSize); + memcpy(dst, src, length); + return length; +} + +size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inBuffer *input) +{ + const char *const istart = (const char *)(input->src) + input->pos; + const char *const iend = (const char *)(input->src) + input->size; + const char *ip = istart; + char *const ostart = (char *)(output->dst) + output->pos; + char *const oend = (char *)(output->dst) + output->size; + char *op = ostart; + U32 someMoreWork = 1; + + while (someMoreWork) { + switch (zds->stage) { + case zdss_init: + ZSTD_resetDStream(zds); /* transparent reset on starting decoding a new frame */ + /* fall-through */ + + case zdss_loadHeader: { + size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize); + if (ZSTD_isError(hSize)) + return hSize; + if (hSize != 0) { /* need more input */ + size_t const toLoad = hSize - zds->lhSize; /* if hSize!=0, hSize > zds->lhSize */ + if (toLoad > (size_t)(iend - ip)) { /* not enough input to load full header */ + memcpy(zds->headerBuffer + zds->lhSize, ip, iend - ip); + zds->lhSize += iend - ip; + input->pos = input->size; + return (MAX(ZSTD_frameHeaderSize_min, hSize) - zds->lhSize) + + ZSTD_blockHeaderSize; /* remaining header bytes + next block header */ + } + memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad); + zds->lhSize = hSize; + ip += toLoad; + break; + } + + /* check for single-pass mode opportunity */ + if (zds->fParams.frameContentSize && zds->fParams.windowSize /* skippable frame if == 0 */ + && (U64)(size_t)(oend - op) >= zds->fParams.frameContentSize) { + size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend - istart); + if (cSize <= (size_t)(iend - istart)) { + size_t const decompressedSize = ZSTD_decompress_usingDDict(zds->dctx, op, oend - op, istart, cSize, zds->ddict); + if (ZSTD_isError(decompressedSize)) + return decompressedSize; + ip = istart + cSize; + op += decompressedSize; + zds->dctx->expected = 0; + zds->stage = zdss_init; + someMoreWork = 0; + break; + } + } + + /* Consume header */ + ZSTD_refDDict(zds->dctx, zds->ddict); + { + size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); /* == ZSTD_frameHeaderSize_prefix */ + CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer, h1Size)); + { + size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); + CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer + h1Size, h2Size)); + } + } + + zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN); + if (zds->fParams.windowSize > zds->maxWindowSize) + return ERROR(frameParameter_windowTooLarge); + + /* Buffers are preallocated, but double check */ + { + size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); + size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; + if (zds->inBuffSize < blockSize) { + return ERROR(GENERIC); + } + if (zds->outBuffSize < neededOutSize) { + return ERROR(GENERIC); + } + zds->blockSize = blockSize; + } + zds->stage = zdss_read; + } + /* pass-through */ + + case zdss_read: { + size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx); + if (neededInSize == 0) { /* end of frame */ + zds->stage = zdss_init; + someMoreWork = 0; + break; + } + if ((size_t)(iend - ip) >= neededInSize) { /* decode directly from src */ + const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx); + size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, + (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart), ip, neededInSize); + if (ZSTD_isError(decodedSize)) + return decodedSize; + ip += neededInSize; + if (!decodedSize && !isSkipFrame) + break; /* this was just a header */ + zds->outEnd = zds->outStart + decodedSize; + zds->stage = zdss_flush; + break; + } + if (ip == iend) { + someMoreWork = 0; + break; + } /* no more input */ + zds->stage = zdss_load; + /* pass-through */ + } + + case zdss_load: { + size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx); + size_t const toLoad = neededInSize - zds->inPos; /* should always be <= remaining space within inBuff */ + size_t loadedSize; + if (toLoad > zds->inBuffSize - zds->inPos) + return ERROR(corruption_detected); /* should never happen */ + loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, iend - ip); + ip += loadedSize; + zds->inPos += loadedSize; + if (loadedSize < toLoad) { + someMoreWork = 0; + break; + } /* not enough input, wait for more */ + + /* decode loaded input */ + { + const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx); + size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart, + zds->inBuff, neededInSize); + if (ZSTD_isError(decodedSize)) + return decodedSize; + zds->inPos = 0; /* input is consumed */ + if (!decodedSize && !isSkipFrame) { + zds->stage = zdss_read; + break; + } /* this was just a header */ + zds->outEnd = zds->outStart + decodedSize; + zds->stage = zdss_flush; + /* pass-through */ + } + } + + case zdss_flush: { + size_t const toFlushSize = zds->outEnd - zds->outStart; + size_t const flushedSize = ZSTD_limitCopy(op, oend - op, zds->outBuff + zds->outStart, toFlushSize); + op += flushedSize; + zds->outStart += flushedSize; + if (flushedSize == toFlushSize) { /* flush completed */ + zds->stage = zdss_read; + if (zds->outStart + zds->blockSize > zds->outBuffSize) + zds->outStart = zds->outEnd = 0; + break; + } + /* cannot complete flush */ + someMoreWork = 0; + break; + } + default: + return ERROR(GENERIC); /* impossible */ + } + } + + /* result */ + input->pos += (size_t)(ip - istart); + output->pos += (size_t)(op - ostart); + { + size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds->dctx); + if (!nextSrcSizeHint) { /* frame fully decoded */ + if (zds->outEnd == zds->outStart) { /* output fully flushed */ + if (zds->hostageByte) { + if (input->pos >= input->size) { + zds->stage = zdss_read; + return 1; + } /* can't release hostage (not present) */ + input->pos++; /* release hostage */ + } + return 0; + } + if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */ + input->pos--; /* note : pos > 0, otherwise, impossible to finish reading last block */ + zds->hostageByte = 1; + } + return 1; + } + nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->dctx) == ZSTDnit_block); /* preload header of next block */ + if (zds->inPos > nextSrcSizeHint) + return ERROR(GENERIC); /* should never happen */ + nextSrcSizeHint -= zds->inPos; /* already loaded*/ + return nextSrcSizeHint; + } +} + +EXPORT_SYMBOL(ZSTD_DCtxWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initDCtx); +EXPORT_SYMBOL(ZSTD_decompressDCtx); +EXPORT_SYMBOL(ZSTD_decompress_usingDict); + +EXPORT_SYMBOL(ZSTD_DDictWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initDDict); +EXPORT_SYMBOL(ZSTD_decompress_usingDDict); + +EXPORT_SYMBOL(ZSTD_DStreamWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initDStream); +EXPORT_SYMBOL(ZSTD_initDStream_usingDDict); +EXPORT_SYMBOL(ZSTD_resetDStream); +EXPORT_SYMBOL(ZSTD_decompressStream); +EXPORT_SYMBOL(ZSTD_DStreamInSize); +EXPORT_SYMBOL(ZSTD_DStreamOutSize); + +EXPORT_SYMBOL(ZSTD_findFrameCompressedSize); +EXPORT_SYMBOL(ZSTD_getFrameContentSize); +EXPORT_SYMBOL(ZSTD_findDecompressedSize); + +EXPORT_SYMBOL(ZSTD_isFrame); +EXPORT_SYMBOL(ZSTD_getDictID_fromDict); +EXPORT_SYMBOL(ZSTD_getDictID_fromDDict); +EXPORT_SYMBOL(ZSTD_getDictID_fromFrame); + +EXPORT_SYMBOL(ZSTD_getFrameParams); +EXPORT_SYMBOL(ZSTD_decompressBegin); +EXPORT_SYMBOL(ZSTD_decompressBegin_usingDict); +EXPORT_SYMBOL(ZSTD_copyDCtx); +EXPORT_SYMBOL(ZSTD_nextSrcSizeToDecompress); +EXPORT_SYMBOL(ZSTD_decompressContinue); +EXPORT_SYMBOL(ZSTD_nextInputType); + +EXPORT_SYMBOL(ZSTD_decompressBlock); +EXPORT_SYMBOL(ZSTD_insertBlock); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("Zstd Decompressor"); diff --git a/lib/zstd/entropy_common.c b/lib/zstd/entropy_common.c new file mode 100644 index 000000000000..2b0a643c32c4 --- /dev/null +++ b/lib/zstd/entropy_common.c @@ -0,0 +1,243 @@ +/* + * Common functions of New Generation Entropy library + * Copyright (C) 2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************* +* Dependencies +***************************************/ +#include "error_private.h" /* ERR_*, ERROR */ +#include "fse.h" +#include "huf.h" +#include "mem.h" + +/*=== Version ===*/ +unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; } + +/*=== Error Management ===*/ +unsigned FSE_isError(size_t code) { return ERR_isError(code); } + +unsigned HUF_isError(size_t code) { return ERR_isError(code); } + +/*-************************************************************** +* FSE NCount encoding-decoding +****************************************************************/ +size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSVPtr, unsigned *tableLogPtr, const void *headerBuffer, size_t hbSize) +{ + const BYTE *const istart = (const BYTE *)headerBuffer; + const BYTE *const iend = istart + hbSize; + const BYTE *ip = istart; + int nbBits; + int remaining; + int threshold; + U32 bitStream; + int bitCount; + unsigned charnum = 0; + int previous0 = 0; + + if (hbSize < 4) + return ERROR(srcSize_wrong); + bitStream = ZSTD_readLE32(ip); + nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */ + if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) + return ERROR(tableLog_tooLarge); + bitStream >>= 4; + bitCount = 4; + *tableLogPtr = nbBits; + remaining = (1 << nbBits) + 1; + threshold = 1 << nbBits; + nbBits++; + + while ((remaining > 1) & (charnum <= *maxSVPtr)) { + if (previous0) { + unsigned n0 = charnum; + while ((bitStream & 0xFFFF) == 0xFFFF) { + n0 += 24; + if (ip < iend - 5) { + ip += 2; + bitStream = ZSTD_readLE32(ip) >> bitCount; + } else { + bitStream >>= 16; + bitCount += 16; + } + } + while ((bitStream & 3) == 3) { + n0 += 3; + bitStream >>= 2; + bitCount += 2; + } + n0 += bitStream & 3; + bitCount += 2; + if (n0 > *maxSVPtr) + return ERROR(maxSymbolValue_tooSmall); + while (charnum < n0) + normalizedCounter[charnum++] = 0; + if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) { + ip += bitCount >> 3; + bitCount &= 7; + bitStream = ZSTD_readLE32(ip) >> bitCount; + } else { + bitStream >>= 2; + } + } + { + int const max = (2 * threshold - 1) - remaining; + int count; + + if ((bitStream & (threshold - 1)) < (U32)max) { + count = bitStream & (threshold - 1); + bitCount += nbBits - 1; + } else { + count = bitStream & (2 * threshold - 1); + if (count >= threshold) + count -= max; + bitCount += nbBits; + } + + count--; /* extra accuracy */ + remaining -= count < 0 ? -count : count; /* -1 means +1 */ + normalizedCounter[charnum++] = (short)count; + previous0 = !count; + while (remaining < threshold) { + nbBits--; + threshold >>= 1; + } + + if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) { + ip += bitCount >> 3; + bitCount &= 7; + } else { + bitCount -= (int)(8 * (iend - 4 - ip)); + ip = iend - 4; + } + bitStream = ZSTD_readLE32(ip) >> (bitCount & 31); + } + } /* while ((remaining>1) & (charnum<=*maxSVPtr)) */ + if (remaining != 1) + return ERROR(corruption_detected); + if (bitCount > 32) + return ERROR(corruption_detected); + *maxSVPtr = charnum - 1; + + ip += (bitCount + 7) >> 3; + return ip - istart; +} + +/*! HUF_readStats() : + Read compact Huffman tree, saved by HUF_writeCTable(). + `huffWeight` is destination buffer. + `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32. + @return : size read from `src` , or an error Code . + Note : Needed by HUF_readCTable() and HUF_readDTableX?() . +*/ +size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 weightTotal; + const BYTE *ip = (const BYTE *)src; + size_t iSize; + size_t oSize; + + if (!srcSize) + return ERROR(srcSize_wrong); + iSize = ip[0]; + /* memset(huffWeight, 0, hwSize); */ /* is not necessary, even though some analyzer complain ... */ + + if (iSize >= 128) { /* special header */ + oSize = iSize - 127; + iSize = ((oSize + 1) / 2); + if (iSize + 1 > srcSize) + return ERROR(srcSize_wrong); + if (oSize >= hwSize) + return ERROR(corruption_detected); + ip += 1; + { + U32 n; + for (n = 0; n < oSize; n += 2) { + huffWeight[n] = ip[n / 2] >> 4; + huffWeight[n + 1] = ip[n / 2] & 15; + } + } + } else { /* header compressed with FSE (normal case) */ + if (iSize + 1 > srcSize) + return ERROR(srcSize_wrong); + oSize = FSE_decompress_wksp(huffWeight, hwSize - 1, ip + 1, iSize, 6, workspace, workspaceSize); /* max (hwSize-1) values decoded, as last one is implied */ + if (FSE_isError(oSize)) + return oSize; + } + + /* collect weight stats */ + memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32)); + weightTotal = 0; + { + U32 n; + for (n = 0; n < oSize; n++) { + if (huffWeight[n] >= HUF_TABLELOG_MAX) + return ERROR(corruption_detected); + rankStats[huffWeight[n]]++; + weightTotal += (1 << huffWeight[n]) >> 1; + } + } + if (weightTotal == 0) + return ERROR(corruption_detected); + + /* get last non-null symbol weight (implied, total must be 2^n) */ + { + U32 const tableLog = BIT_highbit32(weightTotal) + 1; + if (tableLog > HUF_TABLELOG_MAX) + return ERROR(corruption_detected); + *tableLogPtr = tableLog; + /* determine last weight */ + { + U32 const total = 1 << tableLog; + U32 const rest = total - weightTotal; + U32 const verif = 1 << BIT_highbit32(rest); + U32 const lastWeight = BIT_highbit32(rest) + 1; + if (verif != rest) + return ERROR(corruption_detected); /* last value must be a clean power of 2 */ + huffWeight[oSize] = (BYTE)lastWeight; + rankStats[lastWeight]++; + } + } + + /* check tree construction validity */ + if ((rankStats[1] < 2) || (rankStats[1] & 1)) + return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */ + + /* results */ + *nbSymbolsPtr = (U32)(oSize + 1); + return iSize + 1; +} diff --git a/lib/zstd/error_private.h b/lib/zstd/error_private.h new file mode 100644 index 000000000000..1a60b31f706c --- /dev/null +++ b/lib/zstd/error_private.h @@ -0,0 +1,53 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/* Note : this module is expected to remain private, do not expose it */ + +#ifndef ERROR_H_MODULE +#define ERROR_H_MODULE + +/* **************************************** +* Dependencies +******************************************/ +#include <linux/types.h> /* size_t */ +#include <linux/zstd.h> /* enum list */ + +/* **************************************** +* Compiler-specific +******************************************/ +#define ERR_STATIC static __attribute__((unused)) + +/*-**************************************** +* Customization (error_public.h) +******************************************/ +typedef ZSTD_ErrorCode ERR_enum; +#define PREFIX(name) ZSTD_error_##name + +/*-**************************************** +* Error codes handling +******************************************/ +#define ERROR(name) ((size_t)-PREFIX(name)) + +ERR_STATIC unsigned ERR_isError(size_t code) { return (code > ERROR(maxCode)); } + +ERR_STATIC ERR_enum ERR_getErrorCode(size_t code) +{ + if (!ERR_isError(code)) + return (ERR_enum)0; + return (ERR_enum)(0 - code); +} + +#endif /* ERROR_H_MODULE */ diff --git a/lib/zstd/fse.h b/lib/zstd/fse.h new file mode 100644 index 000000000000..7460ab04b191 --- /dev/null +++ b/lib/zstd/fse.h @@ -0,0 +1,575 @@ +/* + * FSE : Finite State Entropy codec + * Public Prototypes declaration + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ +#ifndef FSE_H +#define FSE_H + +/*-***************************************** +* Dependencies +******************************************/ +#include <linux/types.h> /* size_t, ptrdiff_t */ + +/*-***************************************** +* FSE_PUBLIC_API : control library symbols visibility +******************************************/ +#define FSE_PUBLIC_API + +/*------ Version ------*/ +#define FSE_VERSION_MAJOR 0 +#define FSE_VERSION_MINOR 9 +#define FSE_VERSION_RELEASE 0 + +#define FSE_LIB_VERSION FSE_VERSION_MAJOR.FSE_VERSION_MINOR.FSE_VERSION_RELEASE +#define FSE_QUOTE(str) #str +#define FSE_EXPAND_AND_QUOTE(str) FSE_QUOTE(str) +#define FSE_VERSION_STRING FSE_EXPAND_AND_QUOTE(FSE_LIB_VERSION) + +#define FSE_VERSION_NUMBER (FSE_VERSION_MAJOR * 100 * 100 + FSE_VERSION_MINOR * 100 + FSE_VERSION_RELEASE) +FSE_PUBLIC_API unsigned FSE_versionNumber(void); /**< library version number; to be used when checking dll version */ + +/*-***************************************** +* Tool functions +******************************************/ +FSE_PUBLIC_API size_t FSE_compressBound(size_t size); /* maximum compressed size */ + +/* Error Management */ +FSE_PUBLIC_API unsigned FSE_isError(size_t code); /* tells if a return value is an error code */ + +/*-***************************************** +* FSE detailed API +******************************************/ +/*! +FSE_compress() does the following: +1. count symbol occurrence from source[] into table count[] +2. normalize counters so that sum(count[]) == Power_of_2 (2^tableLog) +3. save normalized counters to memory buffer using writeNCount() +4. build encoding table 'CTable' from normalized counters +5. encode the data stream using encoding table 'CTable' + +FSE_decompress() does the following: +1. read normalized counters with readNCount() +2. build decoding table 'DTable' from normalized counters +3. decode the data stream using decoding table 'DTable' + +The following API allows targeting specific sub-functions for advanced tasks. +For example, it's possible to compress several blocks using the same 'CTable', +or to save and provide normalized distribution using external method. +*/ + +/* *** COMPRESSION *** */ +/*! FSE_optimalTableLog(): + dynamically downsize 'tableLog' when conditions are met. + It saves CPU time, by using smaller tables, while preserving or even improving compression ratio. + @return : recommended tableLog (necessarily <= 'maxTableLog') */ +FSE_PUBLIC_API unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue); + +/*! FSE_normalizeCount(): + normalize counts so that sum(count[]) == Power_of_2 (2^tableLog) + 'normalizedCounter' is a table of short, of minimum size (maxSymbolValue+1). + @return : tableLog, + or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_normalizeCount(short *normalizedCounter, unsigned tableLog, const unsigned *count, size_t srcSize, unsigned maxSymbolValue); + +/*! FSE_NCountWriteBound(): + Provides the maximum possible size of an FSE normalized table, given 'maxSymbolValue' and 'tableLog'. + Typically useful for allocation purpose. */ +FSE_PUBLIC_API size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog); + +/*! FSE_writeNCount(): + Compactly save 'normalizedCounter' into 'buffer'. + @return : size of the compressed table, + or an errorCode, which can be tested using FSE_isError(). */ +FSE_PUBLIC_API size_t FSE_writeNCount(void *buffer, size_t bufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog); + +/*! Constructor and Destructor of FSE_CTable. + Note that FSE_CTable size depends on 'tableLog' and 'maxSymbolValue' */ +typedef unsigned FSE_CTable; /* don't allocate that. It's only meant to be more restrictive than void* */ + +/*! FSE_compress_usingCTable(): + Compress `src` using `ct` into `dst` which must be already allocated. + @return : size of compressed data (<= `dstCapacity`), + or 0 if compressed data could not fit into `dst`, + or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_compress_usingCTable(void *dst, size_t dstCapacity, const void *src, size_t srcSize, const FSE_CTable *ct); + +/*! +Tutorial : +---------- +The first step is to count all symbols. FSE_count() does this job very fast. +Result will be saved into 'count', a table of unsigned int, which must be already allocated, and have 'maxSymbolValuePtr[0]+1' cells. +'src' is a table of bytes of size 'srcSize'. All values within 'src' MUST be <= maxSymbolValuePtr[0] +maxSymbolValuePtr[0] will be updated, with its real value (necessarily <= original value) +FSE_count() will return the number of occurrence of the most frequent symbol. +This can be used to know if there is a single symbol within 'src', and to quickly evaluate its compressibility. +If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()). + +The next step is to normalize the frequencies. +FSE_normalizeCount() will ensure that sum of frequencies is == 2 ^'tableLog'. +It also guarantees a minimum of 1 to any Symbol with frequency >= 1. +You can use 'tableLog'==0 to mean "use default tableLog value". +If you are unsure of which tableLog value to use, you can ask FSE_optimalTableLog(), +which will provide the optimal valid tableLog given sourceSize, maxSymbolValue, and a user-defined maximum (0 means "default"). + +The result of FSE_normalizeCount() will be saved into a table, +called 'normalizedCounter', which is a table of signed short. +'normalizedCounter' must be already allocated, and have at least 'maxSymbolValue+1' cells. +The return value is tableLog if everything proceeded as expected. +It is 0 if there is a single symbol within distribution. +If there is an error (ex: invalid tableLog value), the function will return an ErrorCode (which can be tested using FSE_isError()). + +'normalizedCounter' can be saved in a compact manner to a memory area using FSE_writeNCount(). +'buffer' must be already allocated. +For guaranteed success, buffer size must be at least FSE_headerBound(). +The result of the function is the number of bytes written into 'buffer'. +If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError(); ex : buffer size too small). + +'normalizedCounter' can then be used to create the compression table 'CTable'. +The space required by 'CTable' must be already allocated, using FSE_createCTable(). +You can then use FSE_buildCTable() to fill 'CTable'. +If there is an error, both functions will return an ErrorCode (which can be tested using FSE_isError()). + +'CTable' can then be used to compress 'src', with FSE_compress_usingCTable(). +Similar to FSE_count(), the convention is that 'src' is assumed to be a table of char of size 'srcSize' +The function returns the size of compressed data (without header), necessarily <= `dstCapacity`. +If it returns '0', compressed data could not fit into 'dst'. +If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()). +*/ + +/* *** DECOMPRESSION *** */ + +/*! FSE_readNCount(): + Read compactly saved 'normalizedCounter' from 'rBuffer'. + @return : size read from 'rBuffer', + or an errorCode, which can be tested using FSE_isError(). + maxSymbolValuePtr[0] and tableLogPtr[0] will also be updated with their respective values */ +FSE_PUBLIC_API size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSymbolValuePtr, unsigned *tableLogPtr, const void *rBuffer, size_t rBuffSize); + +/*! Constructor and Destructor of FSE_DTable. + Note that its size depends on 'tableLog' */ +typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */ + +/*! FSE_buildDTable(): + Builds 'dt', which must be already allocated, using FSE_createDTable(). + return : 0, or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize); + +/*! FSE_decompress_usingDTable(): + Decompress compressed source `cSrc` of size `cSrcSize` using `dt` + into `dst` which must be already allocated. + @return : size of regenerated data (necessarily <= `dstCapacity`), + or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_decompress_usingDTable(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt); + +/*! +Tutorial : +---------- +(Note : these functions only decompress FSE-compressed blocks. + If block is uncompressed, use memcpy() instead + If block is a single repeated byte, use memset() instead ) + +The first step is to obtain the normalized frequencies of symbols. +This can be performed by FSE_readNCount() if it was saved using FSE_writeNCount(). +'normalizedCounter' must be already allocated, and have at least 'maxSymbolValuePtr[0]+1' cells of signed short. +In practice, that means it's necessary to know 'maxSymbolValue' beforehand, +or size the table to handle worst case situations (typically 256). +FSE_readNCount() will provide 'tableLog' and 'maxSymbolValue'. +The result of FSE_readNCount() is the number of bytes read from 'rBuffer'. +Note that 'rBufferSize' must be at least 4 bytes, even if useful information is less than that. +If there is an error, the function will return an error code, which can be tested using FSE_isError(). + +The next step is to build the decompression tables 'FSE_DTable' from 'normalizedCounter'. +This is performed by the function FSE_buildDTable(). +The space required by 'FSE_DTable' must be already allocated using FSE_createDTable(). +If there is an error, the function will return an error code, which can be tested using FSE_isError(). + +`FSE_DTable` can then be used to decompress `cSrc`, with FSE_decompress_usingDTable(). +`cSrcSize` must be strictly correct, otherwise decompression will fail. +FSE_decompress_usingDTable() result will tell how many bytes were regenerated (<=`dstCapacity`). +If there is an error, the function will return an error code, which can be tested using FSE_isError(). (ex: dst buffer too small) +*/ + +/* *** Dependency *** */ +#include "bitstream.h" + +/* ***************************************** +* Static allocation +*******************************************/ +/* FSE buffer bounds */ +#define FSE_NCOUNTBOUND 512 +#define FSE_BLOCKBOUND(size) (size + (size >> 7)) +#define FSE_COMPRESSBOUND(size) (FSE_NCOUNTBOUND + FSE_BLOCKBOUND(size)) /* Macro version, useful for static allocation */ + +/* It is possible to statically allocate FSE CTable/DTable as a table of FSE_CTable/FSE_DTable using below macros */ +#define FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue) (1 + (1 << (maxTableLog - 1)) + ((maxSymbolValue + 1) * 2)) +#define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1 << maxTableLog)) + +/* ***************************************** +* FSE advanced API +*******************************************/ +/* FSE_count_wksp() : + * Same as FSE_count(), but using an externally provided scratch buffer. + * `workSpace` size must be table of >= `1024` unsigned + */ +size_t FSE_count_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace); + +/* FSE_countFast_wksp() : + * Same as FSE_countFast(), but using an externally provided scratch buffer. + * `workSpace` must be a table of minimum `1024` unsigned + */ +size_t FSE_countFast_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize, unsigned *workSpace); + +/*! FSE_count_simple + * Same as FSE_countFast(), but does not use any additional memory (not even on stack). + * This function is unsafe, and will segfault if any value within `src` is `> *maxSymbolValuePtr` (presuming it's also the size of `count`). +*/ +size_t FSE_count_simple(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize); + +unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus); +/**< same as FSE_optimalTableLog(), which used `minus==2` */ + +size_t FSE_buildCTable_raw(FSE_CTable *ct, unsigned nbBits); +/**< build a fake FSE_CTable, designed for a flat distribution, where each symbol uses nbBits */ + +size_t FSE_buildCTable_rle(FSE_CTable *ct, unsigned char symbolValue); +/**< build a fake FSE_CTable, designed to compress always the same symbolValue */ + +/* FSE_buildCTable_wksp() : + * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`). + * `wkspSize` must be >= `(1<<tableLog)`. + */ +size_t FSE_buildCTable_wksp(FSE_CTable *ct, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, size_t wkspSize); + +size_t FSE_buildDTable_raw(FSE_DTable *dt, unsigned nbBits); +/**< build a fake FSE_DTable, designed to read a flat distribution where each symbol uses nbBits */ + +size_t FSE_buildDTable_rle(FSE_DTable *dt, unsigned char symbolValue); +/**< build a fake FSE_DTable, designed to always generate the same symbolValue */ + +size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize); +/**< same as FSE_decompress(), using an externally allocated `workSpace` produced with `FSE_DTABLE_SIZE_U32(maxLog)` */ + +/* ***************************************** +* FSE symbol compression API +*******************************************/ +/*! + This API consists of small unitary functions, which highly benefit from being inlined. + Hence their body are included in next section. +*/ +typedef struct { + ptrdiff_t value; + const void *stateTable; + const void *symbolTT; + unsigned stateLog; +} FSE_CState_t; + +static void FSE_initCState(FSE_CState_t *CStatePtr, const FSE_CTable *ct); + +static void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *CStatePtr, unsigned symbol); + +static void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *CStatePtr); + +/**< +These functions are inner components of FSE_compress_usingCTable(). +They allow the creation of custom streams, mixing multiple tables and bit sources. + +A key property to keep in mind is that encoding and decoding are done **in reverse direction**. +So the first symbol you will encode is the last you will decode, like a LIFO stack. + +You will need a few variables to track your CStream. They are : + +FSE_CTable ct; // Provided by FSE_buildCTable() +BIT_CStream_t bitStream; // bitStream tracking structure +FSE_CState_t state; // State tracking structure (can have several) + + +The first thing to do is to init bitStream and state. + size_t errorCode = BIT_initCStream(&bitStream, dstBuffer, maxDstSize); + FSE_initCState(&state, ct); + +Note that BIT_initCStream() can produce an error code, so its result should be tested, using FSE_isError(); +You can then encode your input data, byte after byte. +FSE_encodeSymbol() outputs a maximum of 'tableLog' bits at a time. +Remember decoding will be done in reverse direction. + FSE_encodeByte(&bitStream, &state, symbol); + +At any time, you can also add any bit sequence. +Note : maximum allowed nbBits is 25, for compatibility with 32-bits decoders + BIT_addBits(&bitStream, bitField, nbBits); + +The above methods don't commit data to memory, they just store it into local register, for speed. +Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t). +Writing data to memory is a manual operation, performed by the flushBits function. + BIT_flushBits(&bitStream); + +Your last FSE encoding operation shall be to flush your last state value(s). + FSE_flushState(&bitStream, &state); + +Finally, you must close the bitStream. +The function returns the size of CStream in bytes. +If data couldn't fit into dstBuffer, it will return a 0 ( == not compressible) +If there is an error, it returns an errorCode (which can be tested using FSE_isError()). + size_t size = BIT_closeCStream(&bitStream); +*/ + +/* ***************************************** +* FSE symbol decompression API +*******************************************/ +typedef struct { + size_t state; + const void *table; /* precise table may vary, depending on U16 */ +} FSE_DState_t; + +static void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt); + +static unsigned char FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD); + +static unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr); + +/**< +Let's now decompose FSE_decompress_usingDTable() into its unitary components. +You will decode FSE-encoded symbols from the bitStream, +and also any other bitFields you put in, **in reverse order**. + +You will need a few variables to track your bitStream. They are : + +BIT_DStream_t DStream; // Stream context +FSE_DState_t DState; // State context. Multiple ones are possible +FSE_DTable* DTablePtr; // Decoding table, provided by FSE_buildDTable() + +The first thing to do is to init the bitStream. + errorCode = BIT_initDStream(&DStream, srcBuffer, srcSize); + +You should then retrieve your initial state(s) +(in reverse flushing order if you have several ones) : + errorCode = FSE_initDState(&DState, &DStream, DTablePtr); + +You can then decode your data, symbol after symbol. +For information the maximum number of bits read by FSE_decodeSymbol() is 'tableLog'. +Keep in mind that symbols are decoded in reverse order, like a LIFO stack (last in, first out). + unsigned char symbol = FSE_decodeSymbol(&DState, &DStream); + +You can retrieve any bitfield you eventually stored into the bitStream (in reverse order) +Note : maximum allowed nbBits is 25, for 32-bits compatibility + size_t bitField = BIT_readBits(&DStream, nbBits); + +All above operations only read from local register (which size depends on size_t). +Refueling the register from memory is manually performed by the reload method. + endSignal = FSE_reloadDStream(&DStream); + +BIT_reloadDStream() result tells if there is still some more data to read from DStream. +BIT_DStream_unfinished : there is still some data left into the DStream. +BIT_DStream_endOfBuffer : Dstream reached end of buffer. Its container may no longer be completely filled. +BIT_DStream_completed : Dstream reached its exact end, corresponding in general to decompression completed. +BIT_DStream_tooFar : Dstream went too far. Decompression result is corrupted. + +When reaching end of buffer (BIT_DStream_endOfBuffer), progress slowly, notably if you decode multiple symbols per loop, +to properly detect the exact end of stream. +After each decoded symbol, check if DStream is fully consumed using this simple test : + BIT_reloadDStream(&DStream) >= BIT_DStream_completed + +When it's done, verify decompression is fully completed, by checking both DStream and the relevant states. +Checking if DStream has reached its end is performed by : + BIT_endOfDStream(&DStream); +Check also the states. There might be some symbols left there, if some high probability ones (>50%) are possible. + FSE_endOfDState(&DState); +*/ + +/* ***************************************** +* FSE unsafe API +*******************************************/ +static unsigned char FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD); +/* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */ + +/* ***************************************** +* Implementation of inlined functions +*******************************************/ +typedef struct { + int deltaFindState; + U32 deltaNbBits; +} FSE_symbolCompressionTransform; /* total 8 bytes */ + +ZSTD_STATIC void FSE_initCState(FSE_CState_t *statePtr, const FSE_CTable *ct) +{ + const void *ptr = ct; + const U16 *u16ptr = (const U16 *)ptr; + const U32 tableLog = ZSTD_read16(ptr); + statePtr->value = (ptrdiff_t)1 << tableLog; + statePtr->stateTable = u16ptr + 2; + statePtr->symbolTT = ((const U32 *)ct + 1 + (tableLog ? (1 << (tableLog - 1)) : 1)); + statePtr->stateLog = tableLog; +} + +/*! FSE_initCState2() : +* Same as FSE_initCState(), but the first symbol to include (which will be the last to be read) +* uses the smallest state value possible, saving the cost of this symbol */ +ZSTD_STATIC void FSE_initCState2(FSE_CState_t *statePtr, const FSE_CTable *ct, U32 symbol) +{ + FSE_initCState(statePtr, ct); + { + const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol]; + const U16 *stateTable = (const U16 *)(statePtr->stateTable); + U32 nbBitsOut = (U32)((symbolTT.deltaNbBits + (1 << 15)) >> 16); + statePtr->value = (nbBitsOut << 16) - symbolTT.deltaNbBits; + statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState]; + } +} + +ZSTD_STATIC void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *statePtr, U32 symbol) +{ + const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol]; + const U16 *const stateTable = (const U16 *)(statePtr->stateTable); + U32 nbBitsOut = (U32)((statePtr->value + symbolTT.deltaNbBits) >> 16); + BIT_addBits(bitC, statePtr->value, nbBitsOut); + statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState]; +} + +ZSTD_STATIC void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *statePtr) +{ + BIT_addBits(bitC, statePtr->value, statePtr->stateLog); + BIT_flushBits(bitC); +} + +/* ====== Decompression ====== */ + +typedef struct { + U16 tableLog; + U16 fastMode; +} FSE_DTableHeader; /* sizeof U32 */ + +typedef struct { + unsigned short newState; + unsigned char symbol; + unsigned char nbBits; +} FSE_decode_t; /* size == U32 */ + +ZSTD_STATIC void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt) +{ + const void *ptr = dt; + const FSE_DTableHeader *const DTableH = (const FSE_DTableHeader *)ptr; + DStatePtr->state = BIT_readBits(bitD, DTableH->tableLog); + BIT_reloadDStream(bitD); + DStatePtr->table = dt + 1; +} + +ZSTD_STATIC BYTE FSE_peekSymbol(const FSE_DState_t *DStatePtr) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + return DInfo.symbol; +} + +ZSTD_STATIC void FSE_updateState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + U32 const nbBits = DInfo.nbBits; + size_t const lowBits = BIT_readBits(bitD, nbBits); + DStatePtr->state = DInfo.newState + lowBits; +} + +ZSTD_STATIC BYTE FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + U32 const nbBits = DInfo.nbBits; + BYTE const symbol = DInfo.symbol; + size_t const lowBits = BIT_readBits(bitD, nbBits); + + DStatePtr->state = DInfo.newState + lowBits; + return symbol; +} + +/*! FSE_decodeSymbolFast() : + unsafe, only works if no symbol has a probability > 50% */ +ZSTD_STATIC BYTE FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + U32 const nbBits = DInfo.nbBits; + BYTE const symbol = DInfo.symbol; + size_t const lowBits = BIT_readBitsFast(bitD, nbBits); + + DStatePtr->state = DInfo.newState + lowBits; + return symbol; +} + +ZSTD_STATIC unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr) { return DStatePtr->state == 0; } + +/* ************************************************************** +* Tuning parameters +****************************************************************/ +/*!MEMORY_USAGE : +* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) +* Increasing memory usage improves compression ratio +* Reduced memory usage can improve speed, due to cache effect +* Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */ +#ifndef FSE_MAX_MEMORY_USAGE +#define FSE_MAX_MEMORY_USAGE 14 +#endif +#ifndef FSE_DEFAULT_MEMORY_USAGE +#define FSE_DEFAULT_MEMORY_USAGE 13 +#endif + +/*!FSE_MAX_SYMBOL_VALUE : +* Maximum symbol value authorized. +* Required for proper stack allocation */ +#ifndef FSE_MAX_SYMBOL_VALUE +#define FSE_MAX_SYMBOL_VALUE 255 +#endif + +/* ************************************************************** +* template functions type & suffix +****************************************************************/ +#define FSE_FUNCTION_TYPE BYTE +#define FSE_FUNCTION_EXTENSION +#define FSE_DECODE_TYPE FSE_decode_t + +/* *************************************************************** +* Constants +*****************************************************************/ +#define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE - 2) +#define FSE_MAX_TABLESIZE (1U << FSE_MAX_TABLELOG) +#define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE - 1) +#define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE - 2) +#define FSE_MIN_TABLELOG 5 + +#define FSE_TABLELOG_ABSOLUTE_MAX 15 +#if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX +#error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported" +#endif + +#define FSE_TABLESTEP(tableSize) ((tableSize >> 1) + (tableSize >> 3) + 3) + +#endif /* FSE_H */ diff --git a/lib/zstd/fse_compress.c b/lib/zstd/fse_compress.c new file mode 100644 index 000000000000..ef3d1741d532 --- /dev/null +++ b/lib/zstd/fse_compress.c @@ -0,0 +1,795 @@ +/* + * FSE : Finite State Entropy encoder + * Copyright (C) 2013-2015, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************************************** +* Compiler specifics +****************************************************************/ +#define FORCE_INLINE static __always_inline + +/* ************************************************************** +* Includes +****************************************************************/ +#include "bitstream.h" +#include "fse.h" +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/math64.h> +#include <linux/string.h> /* memcpy, memset */ + +/* ************************************************************** +* Error Management +****************************************************************/ +#define FSE_STATIC_ASSERT(c) \ + { \ + enum { FSE_static_assert = 1 / (int)(!!(c)) }; \ + } /* use only *after* variable declarations */ + +/* ************************************************************** +* Templates +****************************************************************/ +/* + designed to be included + for type-specific functions (template emulation in C) + Objective is to write these functions only once, for improved maintenance +*/ + +/* safety checks */ +#ifndef FSE_FUNCTION_EXTENSION +#error "FSE_FUNCTION_EXTENSION must be defined" +#endif +#ifndef FSE_FUNCTION_TYPE +#error "FSE_FUNCTION_TYPE must be defined" +#endif + +/* Function names */ +#define FSE_CAT(X, Y) X##Y +#define FSE_FUNCTION_NAME(X, Y) FSE_CAT(X, Y) +#define FSE_TYPE_NAME(X, Y) FSE_CAT(X, Y) + +/* Function templates */ + +/* FSE_buildCTable_wksp() : + * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`). + * wkspSize should be sized to handle worst case situation, which is `1<<max_tableLog * sizeof(FSE_FUNCTION_TYPE)` + * workSpace must also be properly aligned with FSE_FUNCTION_TYPE requirements + */ +size_t FSE_buildCTable_wksp(FSE_CTable *ct, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize) +{ + U32 const tableSize = 1 << tableLog; + U32 const tableMask = tableSize - 1; + void *const ptr = ct; + U16 *const tableU16 = ((U16 *)ptr) + 2; + void *const FSCT = ((U32 *)ptr) + 1 /* header */ + (tableLog ? tableSize >> 1 : 1); + FSE_symbolCompressionTransform *const symbolTT = (FSE_symbolCompressionTransform *)(FSCT); + U32 const step = FSE_TABLESTEP(tableSize); + U32 highThreshold = tableSize - 1; + + U32 *cumul; + FSE_FUNCTION_TYPE *tableSymbol; + size_t spaceUsed32 = 0; + + cumul = (U32 *)workspace + spaceUsed32; + spaceUsed32 += FSE_MAX_SYMBOL_VALUE + 2; + tableSymbol = (FSE_FUNCTION_TYPE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(FSE_FUNCTION_TYPE) * ((size_t)1 << tableLog), sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + /* CTable header */ + tableU16[-2] = (U16)tableLog; + tableU16[-1] = (U16)maxSymbolValue; + + /* For explanations on how to distribute symbol values over the table : + * http://fastcompression.blogspot.fr/2014/02/fse-distributing-symbol-values.html */ + + /* symbol start positions */ + { + U32 u; + cumul[0] = 0; + for (u = 1; u <= maxSymbolValue + 1; u++) { + if (normalizedCounter[u - 1] == -1) { /* Low proba symbol */ + cumul[u] = cumul[u - 1] + 1; + tableSymbol[highThreshold--] = (FSE_FUNCTION_TYPE)(u - 1); + } else { + cumul[u] = cumul[u - 1] + normalizedCounter[u - 1]; + } + } + cumul[maxSymbolValue + 1] = tableSize + 1; + } + + /* Spread symbols */ + { + U32 position = 0; + U32 symbol; + for (symbol = 0; symbol <= maxSymbolValue; symbol++) { + int nbOccurences; + for (nbOccurences = 0; nbOccurences < normalizedCounter[symbol]; nbOccurences++) { + tableSymbol[position] = (FSE_FUNCTION_TYPE)symbol; + position = (position + step) & tableMask; + while (position > highThreshold) + position = (position + step) & tableMask; /* Low proba area */ + } + } + + if (position != 0) + return ERROR(GENERIC); /* Must have gone through all positions */ + } + + /* Build table */ + { + U32 u; + for (u = 0; u < tableSize; u++) { + FSE_FUNCTION_TYPE s = tableSymbol[u]; /* note : static analyzer may not understand tableSymbol is properly initialized */ + tableU16[cumul[s]++] = (U16)(tableSize + u); /* TableU16 : sorted by symbol order; gives next state value */ + } + } + + /* Build Symbol Transformation Table */ + { + unsigned total = 0; + unsigned s; + for (s = 0; s <= maxSymbolValue; s++) { + switch (normalizedCounter[s]) { + case 0: break; + + case -1: + case 1: + symbolTT[s].deltaNbBits = (tableLog << 16) - (1 << tableLog); + symbolTT[s].deltaFindState = total - 1; + total++; + break; + default: { + U32 const maxBitsOut = tableLog - BIT_highbit32(normalizedCounter[s] - 1); + U32 const minStatePlus = normalizedCounter[s] << maxBitsOut; + symbolTT[s].deltaNbBits = (maxBitsOut << 16) - minStatePlus; + symbolTT[s].deltaFindState = total - normalizedCounter[s]; + total += normalizedCounter[s]; + } + } + } + } + + return 0; +} + +/*-************************************************************** +* FSE NCount encoding-decoding +****************************************************************/ +size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog) +{ + size_t const maxHeaderSize = (((maxSymbolValue + 1) * tableLog) >> 3) + 3; + return maxSymbolValue ? maxHeaderSize : FSE_NCOUNTBOUND; /* maxSymbolValue==0 ? use default */ +} + +static size_t FSE_writeNCount_generic(void *header, size_t headerBufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, + unsigned writeIsSafe) +{ + BYTE *const ostart = (BYTE *)header; + BYTE *out = ostart; + BYTE *const oend = ostart + headerBufferSize; + int nbBits; + const int tableSize = 1 << tableLog; + int remaining; + int threshold; + U32 bitStream; + int bitCount; + unsigned charnum = 0; + int previous0 = 0; + + bitStream = 0; + bitCount = 0; + /* Table Size */ + bitStream += (tableLog - FSE_MIN_TABLELOG) << bitCount; + bitCount += 4; + + /* Init */ + remaining = tableSize + 1; /* +1 for extra accuracy */ + threshold = tableSize; + nbBits = tableLog + 1; + + while (remaining > 1) { /* stops at 1 */ + if (previous0) { + unsigned start = charnum; + while (!normalizedCounter[charnum]) + charnum++; + while (charnum >= start + 24) { + start += 24; + bitStream += 0xFFFFU << bitCount; + if ((!writeIsSafe) && (out > oend - 2)) + return ERROR(dstSize_tooSmall); /* Buffer overflow */ + out[0] = (BYTE)bitStream; + out[1] = (BYTE)(bitStream >> 8); + out += 2; + bitStream >>= 16; + } + while (charnum >= start + 3) { + start += 3; + bitStream += 3 << bitCount; + bitCount += 2; + } + bitStream += (charnum - start) << bitCount; + bitCount += 2; + if (bitCount > 16) { + if ((!writeIsSafe) && (out > oend - 2)) + return ERROR(dstSize_tooSmall); /* Buffer overflow */ + out[0] = (BYTE)bitStream; + out[1] = (BYTE)(bitStream >> 8); + out += 2; + bitStream >>= 16; + bitCount -= 16; + } + } + { + int count = normalizedCounter[charnum++]; + int const max = (2 * threshold - 1) - remaining; + remaining -= count < 0 ? -count : count; + count++; /* +1 for extra accuracy */ + if (count >= threshold) + count += max; /* [0..max[ [max..threshold[ (...) [threshold+max 2*threshold[ */ + bitStream += count << bitCount; + bitCount += nbBits; + bitCount -= (count < max); + previous0 = (count == 1); + if (remaining < 1) + return ERROR(GENERIC); + while (remaining < threshold) + nbBits--, threshold >>= 1; + } + if (bitCount > 16) { + if ((!writeIsSafe) && (out > oend - 2)) + return ERROR(dstSize_tooSmall); /* Buffer overflow */ + out[0] = (BYTE)bitStream; + out[1] = (BYTE)(bitStream >> 8); + out += 2; + bitStream >>= 16; + bitCount -= 16; + } + } + + /* flush remaining bitStream */ + if ((!writeIsSafe) && (out > oend - 2)) + return ERROR(dstSize_tooSmall); /* Buffer overflow */ + out[0] = (BYTE)bitStream; + out[1] = (BYTE)(bitStream >> 8); + out += (bitCount + 7) / 8; + + if (charnum > maxSymbolValue + 1) + return ERROR(GENERIC); + + return (out - ostart); +} + +size_t FSE_writeNCount(void *buffer, size_t bufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog) +{ + if (tableLog > FSE_MAX_TABLELOG) + return ERROR(tableLog_tooLarge); /* Unsupported */ + if (tableLog < FSE_MIN_TABLELOG) + return ERROR(GENERIC); /* Unsupported */ + + if (bufferSize < FSE_NCountWriteBound(maxSymbolValue, tableLog)) + return FSE_writeNCount_generic(buffer, bufferSize, normalizedCounter, maxSymbolValue, tableLog, 0); + + return FSE_writeNCount_generic(buffer, bufferSize, normalizedCounter, maxSymbolValue, tableLog, 1); +} + +/*-************************************************************** +* Counting histogram +****************************************************************/ +/*! FSE_count_simple + This function counts byte values within `src`, and store the histogram into table `count`. + It doesn't use any additional memory. + But this function is unsafe : it doesn't check that all values within `src` can fit into `count`. + For this reason, prefer using a table `count` with 256 elements. + @return : count of most numerous element +*/ +size_t FSE_count_simple(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize) +{ + const BYTE *ip = (const BYTE *)src; + const BYTE *const end = ip + srcSize; + unsigned maxSymbolValue = *maxSymbolValuePtr; + unsigned max = 0; + + memset(count, 0, (maxSymbolValue + 1) * sizeof(*count)); + if (srcSize == 0) { + *maxSymbolValuePtr = 0; + return 0; + } + + while (ip < end) + count[*ip++]++; + + while (!count[maxSymbolValue]) + maxSymbolValue--; + *maxSymbolValuePtr = maxSymbolValue; + + { + U32 s; + for (s = 0; s <= maxSymbolValue; s++) + if (count[s] > max) + max = count[s]; + } + + return (size_t)max; +} + +/* FSE_count_parallel_wksp() : + * Same as FSE_count_parallel(), but using an externally provided scratch buffer. + * `workSpace` size must be a minimum of `1024 * sizeof(unsigned)`` */ +static size_t FSE_count_parallel_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned checkMax, + unsigned *const workSpace) +{ + const BYTE *ip = (const BYTE *)source; + const BYTE *const iend = ip + sourceSize; + unsigned maxSymbolValue = *maxSymbolValuePtr; + unsigned max = 0; + U32 *const Counting1 = workSpace; + U32 *const Counting2 = Counting1 + 256; + U32 *const Counting3 = Counting2 + 256; + U32 *const Counting4 = Counting3 + 256; + + memset(Counting1, 0, 4 * 256 * sizeof(unsigned)); + + /* safety checks */ + if (!sourceSize) { + memset(count, 0, maxSymbolValue + 1); + *maxSymbolValuePtr = 0; + return 0; + } + if (!maxSymbolValue) + maxSymbolValue = 255; /* 0 == default */ + + /* by stripes of 16 bytes */ + { + U32 cached = ZSTD_read32(ip); + ip += 4; + while (ip < iend - 15) { + U32 c = cached; + cached = ZSTD_read32(ip); + ip += 4; + Counting1[(BYTE)c]++; + Counting2[(BYTE)(c >> 8)]++; + Counting3[(BYTE)(c >> 16)]++; + Counting4[c >> 24]++; + c = cached; + cached = ZSTD_read32(ip); + ip += 4; + Counting1[(BYTE)c]++; + Counting2[(BYTE)(c >> 8)]++; + Counting3[(BYTE)(c >> 16)]++; + Counting4[c >> 24]++; + c = cached; + cached = ZSTD_read32(ip); + ip += 4; + Counting1[(BYTE)c]++; + Counting2[(BYTE)(c >> 8)]++; + Counting3[(BYTE)(c >> 16)]++; + Counting4[c >> 24]++; + c = cached; + cached = ZSTD_read32(ip); + ip += 4; + Counting1[(BYTE)c]++; + Counting2[(BYTE)(c >> 8)]++; + Counting3[(BYTE)(c >> 16)]++; + Counting4[c >> 24]++; + } + ip -= 4; + } + + /* finish last symbols */ + while (ip < iend) + Counting1[*ip++]++; + + if (checkMax) { /* verify stats will fit into destination table */ + U32 s; + for (s = 255; s > maxSymbolValue; s--) { + Counting1[s] += Counting2[s] + Counting3[s] + Counting4[s]; + if (Counting1[s]) + return ERROR(maxSymbolValue_tooSmall); + } + } + + { + U32 s; + for (s = 0; s <= maxSymbolValue; s++) { + count[s] = Counting1[s] + Counting2[s] + Counting3[s] + Counting4[s]; + if (count[s] > max) + max = count[s]; + } + } + + while (!count[maxSymbolValue]) + maxSymbolValue--; + *maxSymbolValuePtr = maxSymbolValue; + return (size_t)max; +} + +/* FSE_countFast_wksp() : + * Same as FSE_countFast(), but using an externally provided scratch buffer. + * `workSpace` size must be table of >= `1024` unsigned */ +size_t FSE_countFast_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace) +{ + if (sourceSize < 1500) + return FSE_count_simple(count, maxSymbolValuePtr, source, sourceSize); + return FSE_count_parallel_wksp(count, maxSymbolValuePtr, source, sourceSize, 0, workSpace); +} + +/* FSE_count_wksp() : + * Same as FSE_count(), but using an externally provided scratch buffer. + * `workSpace` size must be table of >= `1024` unsigned */ +size_t FSE_count_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace) +{ + if (*maxSymbolValuePtr < 255) + return FSE_count_parallel_wksp(count, maxSymbolValuePtr, source, sourceSize, 1, workSpace); + *maxSymbolValuePtr = 255; + return FSE_countFast_wksp(count, maxSymbolValuePtr, source, sourceSize, workSpace); +} + +/*-************************************************************** +* FSE Compression Code +****************************************************************/ +/*! FSE_sizeof_CTable() : + FSE_CTable is a variable size structure which contains : + `U16 tableLog;` + `U16 maxSymbolValue;` + `U16 nextStateNumber[1 << tableLog];` // This size is variable + `FSE_symbolCompressionTransform symbolTT[maxSymbolValue+1];` // This size is variable +Allocation is manual (C standard does not support variable-size structures). +*/ +size_t FSE_sizeof_CTable(unsigned maxSymbolValue, unsigned tableLog) +{ + if (tableLog > FSE_MAX_TABLELOG) + return ERROR(tableLog_tooLarge); + return FSE_CTABLE_SIZE_U32(tableLog, maxSymbolValue) * sizeof(U32); +} + +/* provides the minimum logSize to safely represent a distribution */ +static unsigned FSE_minTableLog(size_t srcSize, unsigned maxSymbolValue) +{ + U32 minBitsSrc = BIT_highbit32((U32)(srcSize - 1)) + 1; + U32 minBitsSymbols = BIT_highbit32(maxSymbolValue) + 2; + U32 minBits = minBitsSrc < minBitsSymbols ? minBitsSrc : minBitsSymbols; + return minBits; +} + +unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus) +{ + U32 maxBitsSrc = BIT_highbit32((U32)(srcSize - 1)) - minus; + U32 tableLog = maxTableLog; + U32 minBits = FSE_minTableLog(srcSize, maxSymbolValue); + if (tableLog == 0) + tableLog = FSE_DEFAULT_TABLELOG; + if (maxBitsSrc < tableLog) + tableLog = maxBitsSrc; /* Accuracy can be reduced */ + if (minBits > tableLog) + tableLog = minBits; /* Need a minimum to safely represent all symbol values */ + if (tableLog < FSE_MIN_TABLELOG) + tableLog = FSE_MIN_TABLELOG; + if (tableLog > FSE_MAX_TABLELOG) + tableLog = FSE_MAX_TABLELOG; + return tableLog; +} + +unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue) +{ + return FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 2); +} + +/* Secondary normalization method. + To be used when primary method fails. */ + +static size_t FSE_normalizeM2(short *norm, U32 tableLog, const unsigned *count, size_t total, U32 maxSymbolValue) +{ + short const NOT_YET_ASSIGNED = -2; + U32 s; + U32 distributed = 0; + U32 ToDistribute; + + /* Init */ + U32 const lowThreshold = (U32)(total >> tableLog); + U32 lowOne = (U32)((total * 3) >> (tableLog + 1)); + + for (s = 0; s <= maxSymbolValue; s++) { + if (count[s] == 0) { + norm[s] = 0; + continue; + } + if (count[s] <= lowThreshold) { + norm[s] = -1; + distributed++; + total -= count[s]; + continue; + } + if (count[s] <= lowOne) { + norm[s] = 1; + distributed++; + total -= count[s]; + continue; + } + + norm[s] = NOT_YET_ASSIGNED; + } + ToDistribute = (1 << tableLog) - distributed; + + if ((total / ToDistribute) > lowOne) { + /* risk of rounding to zero */ + lowOne = (U32)((total * 3) / (ToDistribute * 2)); + for (s = 0; s <= maxSymbolValue; s++) { + if ((norm[s] == NOT_YET_ASSIGNED) && (count[s] <= lowOne)) { + norm[s] = 1; + distributed++; + total -= count[s]; + continue; + } + } + ToDistribute = (1 << tableLog) - distributed; + } + + if (distributed == maxSymbolValue + 1) { + /* all values are pretty poor; + probably incompressible data (should have already been detected); + find max, then give all remaining points to max */ + U32 maxV = 0, maxC = 0; + for (s = 0; s <= maxSymbolValue; s++) + if (count[s] > maxC) + maxV = s, maxC = count[s]; + norm[maxV] += (short)ToDistribute; + return 0; + } + + if (total == 0) { + /* all of the symbols were low enough for the lowOne or lowThreshold */ + for (s = 0; ToDistribute > 0; s = (s + 1) % (maxSymbolValue + 1)) + if (norm[s] > 0) + ToDistribute--, norm[s]++; + return 0; + } + + { + U64 const vStepLog = 62 - tableLog; + U64 const mid = (1ULL << (vStepLog - 1)) - 1; + U64 const rStep = div_u64((((U64)1 << vStepLog) * ToDistribute) + mid, (U32)total); /* scale on remaining */ + U64 tmpTotal = mid; + for (s = 0; s <= maxSymbolValue; s++) { + if (norm[s] == NOT_YET_ASSIGNED) { + U64 const end = tmpTotal + (count[s] * rStep); + U32 const sStart = (U32)(tmpTotal >> vStepLog); + U32 const sEnd = (U32)(end >> vStepLog); + U32 const weight = sEnd - sStart; + if (weight < 1) + return ERROR(GENERIC); + norm[s] = (short)weight; + tmpTotal = end; + } + } + } + + return 0; +} + +size_t FSE_normalizeCount(short *normalizedCounter, unsigned tableLog, const unsigned *count, size_t total, unsigned maxSymbolValue) +{ + /* Sanity checks */ + if (tableLog == 0) + tableLog = FSE_DEFAULT_TABLELOG; + if (tableLog < FSE_MIN_TABLELOG) + return ERROR(GENERIC); /* Unsupported size */ + if (tableLog > FSE_MAX_TABLELOG) + return ERROR(tableLog_tooLarge); /* Unsupported size */ + if (tableLog < FSE_minTableLog(total, maxSymbolValue)) + return ERROR(GENERIC); /* Too small tableLog, compression potentially impossible */ + + { + U32 const rtbTable[] = {0, 473195, 504333, 520860, 550000, 700000, 750000, 830000}; + U64 const scale = 62 - tableLog; + U64 const step = div_u64((U64)1 << 62, (U32)total); /* <== here, one division ! */ + U64 const vStep = 1ULL << (scale - 20); + int stillToDistribute = 1 << tableLog; + unsigned s; + unsigned largest = 0; + short largestP = 0; + U32 lowThreshold = (U32)(total >> tableLog); + + for (s = 0; s <= maxSymbolValue; s++) { + if (count[s] == total) + return 0; /* rle special case */ + if (count[s] == 0) { + normalizedCounter[s] = 0; + continue; + } + if (count[s] <= lowThreshold) { + normalizedCounter[s] = -1; + stillToDistribute--; + } else { + short proba = (short)((count[s] * step) >> scale); + if (proba < 8) { + U64 restToBeat = vStep * rtbTable[proba]; + proba += (count[s] * step) - ((U64)proba << scale) > restToBeat; + } + if (proba > largestP) + largestP = proba, largest = s; + normalizedCounter[s] = proba; + stillToDistribute -= proba; + } + } + if (-stillToDistribute >= (normalizedCounter[largest] >> 1)) { + /* corner case, need another normalization method */ + size_t const errorCode = FSE_normalizeM2(normalizedCounter, tableLog, count, total, maxSymbolValue); + if (FSE_isError(errorCode)) + return errorCode; + } else + normalizedCounter[largest] += (short)stillToDistribute; + } + + return tableLog; +} + +/* fake FSE_CTable, for raw (uncompressed) input */ +size_t FSE_buildCTable_raw(FSE_CTable *ct, unsigned nbBits) +{ + const unsigned tableSize = 1 << nbBits; + const unsigned tableMask = tableSize - 1; + const unsigned maxSymbolValue = tableMask; + void *const ptr = ct; + U16 *const tableU16 = ((U16 *)ptr) + 2; + void *const FSCT = ((U32 *)ptr) + 1 /* header */ + (tableSize >> 1); /* assumption : tableLog >= 1 */ + FSE_symbolCompressionTransform *const symbolTT = (FSE_symbolCompressionTransform *)(FSCT); + unsigned s; + + /* Sanity checks */ + if (nbBits < 1) + return ERROR(GENERIC); /* min size */ + + /* header */ + tableU16[-2] = (U16)nbBits; + tableU16[-1] = (U16)maxSymbolValue; + + /* Build table */ + for (s = 0; s < tableSize; s++) + tableU16[s] = (U16)(tableSize + s); + + /* Build Symbol Transformation Table */ + { + const U32 deltaNbBits = (nbBits << 16) - (1 << nbBits); + for (s = 0; s <= maxSymbolValue; s++) { + symbolTT[s].deltaNbBits = deltaNbBits; + symbolTT[s].deltaFindState = s - 1; + } + } + + return 0; +} + +/* fake FSE_CTable, for rle input (always same symbol) */ +size_t FSE_buildCTable_rle(FSE_CTable *ct, BYTE symbolValue) +{ + void *ptr = ct; + U16 *tableU16 = ((U16 *)ptr) + 2; + void *FSCTptr = (U32 *)ptr + 2; + FSE_symbolCompressionTransform *symbolTT = (FSE_symbolCompressionTransform *)FSCTptr; + + /* header */ + tableU16[-2] = (U16)0; + tableU16[-1] = (U16)symbolValue; + + /* Build table */ + tableU16[0] = 0; + tableU16[1] = 0; /* just in case */ + + /* Build Symbol Transformation Table */ + symbolTT[symbolValue].deltaNbBits = 0; + symbolTT[symbolValue].deltaFindState = 0; + + return 0; +} + +static size_t FSE_compress_usingCTable_generic(void *dst, size_t dstSize, const void *src, size_t srcSize, const FSE_CTable *ct, const unsigned fast) +{ + const BYTE *const istart = (const BYTE *)src; + const BYTE *const iend = istart + srcSize; + const BYTE *ip = iend; + + BIT_CStream_t bitC; + FSE_CState_t CState1, CState2; + + /* init */ + if (srcSize <= 2) + return 0; + { + size_t const initError = BIT_initCStream(&bitC, dst, dstSize); + if (FSE_isError(initError)) + return 0; /* not enough space available to write a bitstream */ + } + +#define FSE_FLUSHBITS(s) (fast ? BIT_flushBitsFast(s) : BIT_flushBits(s)) + + if (srcSize & 1) { + FSE_initCState2(&CState1, ct, *--ip); + FSE_initCState2(&CState2, ct, *--ip); + FSE_encodeSymbol(&bitC, &CState1, *--ip); + FSE_FLUSHBITS(&bitC); + } else { + FSE_initCState2(&CState2, ct, *--ip); + FSE_initCState2(&CState1, ct, *--ip); + } + + /* join to mod 4 */ + srcSize -= 2; + if ((sizeof(bitC.bitContainer) * 8 > FSE_MAX_TABLELOG * 4 + 7) && (srcSize & 2)) { /* test bit 2 */ + FSE_encodeSymbol(&bitC, &CState2, *--ip); + FSE_encodeSymbol(&bitC, &CState1, *--ip); + FSE_FLUSHBITS(&bitC); + } + + /* 2 or 4 encoding per loop */ + while (ip > istart) { + + FSE_encodeSymbol(&bitC, &CState2, *--ip); + + if (sizeof(bitC.bitContainer) * 8 < FSE_MAX_TABLELOG * 2 + 7) /* this test must be static */ + FSE_FLUSHBITS(&bitC); + + FSE_encodeSymbol(&bitC, &CState1, *--ip); + + if (sizeof(bitC.bitContainer) * 8 > FSE_MAX_TABLELOG * 4 + 7) { /* this test must be static */ + FSE_encodeSymbol(&bitC, &CState2, *--ip); + FSE_encodeSymbol(&bitC, &CState1, *--ip); + } + + FSE_FLUSHBITS(&bitC); + } + + FSE_flushCState(&bitC, &CState2); + FSE_flushCState(&bitC, &CState1); + return BIT_closeCStream(&bitC); +} + +size_t FSE_compress_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const FSE_CTable *ct) +{ + unsigned const fast = (dstSize >= FSE_BLOCKBOUND(srcSize)); + + if (fast) + return FSE_compress_usingCTable_generic(dst, dstSize, src, srcSize, ct, 1); + else + return FSE_compress_usingCTable_generic(dst, dstSize, src, srcSize, ct, 0); +} + +size_t FSE_compressBound(size_t size) { return FSE_COMPRESSBOUND(size); } diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c new file mode 100644 index 000000000000..a84300e5a013 --- /dev/null +++ b/lib/zstd/fse_decompress.c @@ -0,0 +1,332 @@ +/* + * FSE : Finite State Entropy decoder + * Copyright (C) 2013-2015, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************************************** +* Compiler specifics +****************************************************************/ +#define FORCE_INLINE static __always_inline + +/* ************************************************************** +* Includes +****************************************************************/ +#include "bitstream.h" +#include "fse.h" +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/string.h> /* memcpy, memset */ + +/* ************************************************************** +* Error Management +****************************************************************/ +#define FSE_isError ERR_isError +#define FSE_STATIC_ASSERT(c) \ + { \ + enum { FSE_static_assert = 1 / (int)(!!(c)) }; \ + } /* use only *after* variable declarations */ + +/* check and forward error code */ +#define CHECK_F(f) \ + { \ + size_t const e = f; \ + if (FSE_isError(e)) \ + return e; \ + } + +/* ************************************************************** +* Templates +****************************************************************/ +/* + designed to be included + for type-specific functions (template emulation in C) + Objective is to write these functions only once, for improved maintenance +*/ + +/* safety checks */ +#ifndef FSE_FUNCTION_EXTENSION +#error "FSE_FUNCTION_EXTENSION must be defined" +#endif +#ifndef FSE_FUNCTION_TYPE +#error "FSE_FUNCTION_TYPE must be defined" +#endif + +/* Function names */ +#define FSE_CAT(X, Y) X##Y +#define FSE_FUNCTION_NAME(X, Y) FSE_CAT(X, Y) +#define FSE_TYPE_NAME(X, Y) FSE_CAT(X, Y) + +/* Function templates */ + +size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize) +{ + void *const tdPtr = dt + 1; /* because *dt is unsigned, 32-bits aligned on 32-bits */ + FSE_DECODE_TYPE *const tableDecode = (FSE_DECODE_TYPE *)(tdPtr); + U16 *symbolNext = (U16 *)workspace; + + U32 const maxSV1 = maxSymbolValue + 1; + U32 const tableSize = 1 << tableLog; + U32 highThreshold = tableSize - 1; + + /* Sanity Checks */ + if (workspaceSize < sizeof(U16) * (FSE_MAX_SYMBOL_VALUE + 1)) + return ERROR(tableLog_tooLarge); + if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) + return ERROR(maxSymbolValue_tooLarge); + if (tableLog > FSE_MAX_TABLELOG) + return ERROR(tableLog_tooLarge); + + /* Init, lay down lowprob symbols */ + { + FSE_DTableHeader DTableH; + DTableH.tableLog = (U16)tableLog; + DTableH.fastMode = 1; + { + S16 const largeLimit = (S16)(1 << (tableLog - 1)); + U32 s; + for (s = 0; s < maxSV1; s++) { + if (normalizedCounter[s] == -1) { + tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s; + symbolNext[s] = 1; + } else { + if (normalizedCounter[s] >= largeLimit) + DTableH.fastMode = 0; + symbolNext[s] = normalizedCounter[s]; + } + } + } + memcpy(dt, &DTableH, sizeof(DTableH)); + } + + /* Spread symbols */ + { + U32 const tableMask = tableSize - 1; + U32 const step = FSE_TABLESTEP(tableSize); + U32 s, position = 0; + for (s = 0; s < maxSV1; s++) { + int i; + for (i = 0; i < normalizedCounter[s]; i++) { + tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s; + position = (position + step) & tableMask; + while (position > highThreshold) + position = (position + step) & tableMask; /* lowprob area */ + } + } + if (position != 0) + return ERROR(GENERIC); /* position must reach all cells once, otherwise normalizedCounter is incorrect */ + } + + /* Build Decoding table */ + { + U32 u; + for (u = 0; u < tableSize; u++) { + FSE_FUNCTION_TYPE const symbol = (FSE_FUNCTION_TYPE)(tableDecode[u].symbol); + U16 nextState = symbolNext[symbol]++; + tableDecode[u].nbBits = (BYTE)(tableLog - BIT_highbit32((U32)nextState)); + tableDecode[u].newState = (U16)((nextState << tableDecode[u].nbBits) - tableSize); + } + } + + return 0; +} + +/*-******************************************************* +* Decompression (Byte symbols) +*********************************************************/ +size_t FSE_buildDTable_rle(FSE_DTable *dt, BYTE symbolValue) +{ + void *ptr = dt; + FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr; + void *dPtr = dt + 1; + FSE_decode_t *const cell = (FSE_decode_t *)dPtr; + + DTableH->tableLog = 0; + DTableH->fastMode = 0; + + cell->newState = 0; + cell->symbol = symbolValue; + cell->nbBits = 0; + + return 0; +} + +size_t FSE_buildDTable_raw(FSE_DTable *dt, unsigned nbBits) +{ + void *ptr = dt; + FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr; + void *dPtr = dt + 1; + FSE_decode_t *const dinfo = (FSE_decode_t *)dPtr; + const unsigned tableSize = 1 << nbBits; + const unsigned tableMask = tableSize - 1; + const unsigned maxSV1 = tableMask + 1; + unsigned s; + + /* Sanity checks */ + if (nbBits < 1) + return ERROR(GENERIC); /* min size */ + + /* Build Decoding Table */ + DTableH->tableLog = (U16)nbBits; + DTableH->fastMode = 1; + for (s = 0; s < maxSV1; s++) { + dinfo[s].newState = 0; + dinfo[s].symbol = (BYTE)s; + dinfo[s].nbBits = (BYTE)nbBits; + } + + return 0; +} + +FORCE_INLINE size_t FSE_decompress_usingDTable_generic(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt, + const unsigned fast) +{ + BYTE *const ostart = (BYTE *)dst; + BYTE *op = ostart; + BYTE *const omax = op + maxDstSize; + BYTE *const olimit = omax - 3; + + BIT_DStream_t bitD; + FSE_DState_t state1; + FSE_DState_t state2; + + /* Init */ + CHECK_F(BIT_initDStream(&bitD, cSrc, cSrcSize)); + + FSE_initDState(&state1, &bitD, dt); + FSE_initDState(&state2, &bitD, dt); + +#define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD) + + /* 4 symbols per loop */ + for (; (BIT_reloadDStream(&bitD) == BIT_DStream_unfinished) & (op < olimit); op += 4) { + op[0] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */ + BIT_reloadDStream(&bitD); + + op[1] = FSE_GETSYMBOL(&state2); + + if (FSE_MAX_TABLELOG * 4 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */ + { + if (BIT_reloadDStream(&bitD) > BIT_DStream_unfinished) { + op += 2; + break; + } + } + + op[2] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */ + BIT_reloadDStream(&bitD); + + op[3] = FSE_GETSYMBOL(&state2); + } + + /* tail */ + /* note : BIT_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly BIT_DStream_completed */ + while (1) { + if (op > (omax - 2)) + return ERROR(dstSize_tooSmall); + *op++ = FSE_GETSYMBOL(&state1); + if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) { + *op++ = FSE_GETSYMBOL(&state2); + break; + } + + if (op > (omax - 2)) + return ERROR(dstSize_tooSmall); + *op++ = FSE_GETSYMBOL(&state2); + if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) { + *op++ = FSE_GETSYMBOL(&state1); + break; + } + } + + return op - ostart; +} + +size_t FSE_decompress_usingDTable(void *dst, size_t originalSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt) +{ + const void *ptr = dt; + const FSE_DTableHeader *DTableH = (const FSE_DTableHeader *)ptr; + const U32 fastMode = DTableH->fastMode; + + /* select fast mode (static) */ + if (fastMode) + return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1); + return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0); +} + +size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize) +{ + const BYTE *const istart = (const BYTE *)cSrc; + const BYTE *ip = istart; + unsigned tableLog; + unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE; + size_t NCountLength; + + FSE_DTable *dt; + short *counting; + size_t spaceUsed32 = 0; + + FSE_STATIC_ASSERT(sizeof(FSE_DTable) == sizeof(U32)); + + dt = (FSE_DTable *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += FSE_DTABLE_SIZE_U32(maxLog); + counting = (short *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(short) * (FSE_MAX_SYMBOL_VALUE + 1), sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + /* normal FSE decoding mode */ + NCountLength = FSE_readNCount(counting, &maxSymbolValue, &tableLog, istart, cSrcSize); + if (FSE_isError(NCountLength)) + return NCountLength; + // if (NCountLength >= cSrcSize) return ERROR(srcSize_wrong); /* too small input size; supposed to be already checked in NCountLength, only remaining + // case : NCountLength==cSrcSize */ + if (tableLog > maxLog) + return ERROR(tableLog_tooLarge); + ip += NCountLength; + cSrcSize -= NCountLength; + + CHECK_F(FSE_buildDTable_wksp(dt, counting, maxSymbolValue, tableLog, workspace, workspaceSize)); + + return FSE_decompress_usingDTable(dst, dstCapacity, ip, cSrcSize, dt); /* always return, even if it is an error code */ +} diff --git a/lib/zstd/huf.h b/lib/zstd/huf.h new file mode 100644 index 000000000000..2143da28d952 --- /dev/null +++ b/lib/zstd/huf.h @@ -0,0 +1,212 @@ +/* + * Huffman coder, part of New Generation Entropy library + * header file + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ +#ifndef HUF_H_298734234 +#define HUF_H_298734234 + +/* *** Dependencies *** */ +#include <linux/types.h> /* size_t */ + +/* *** Tool functions *** */ +#define HUF_BLOCKSIZE_MAX (128 * 1024) /**< maximum input size for a single block compressed with HUF_compress */ +size_t HUF_compressBound(size_t size); /**< maximum compressed size (worst case) */ + +/* Error Management */ +unsigned HUF_isError(size_t code); /**< tells if a return value is an error code */ + +/* *** Advanced function *** */ + +/** HUF_compress4X_wksp() : +* Same as HUF_compress2(), but uses externally allocated `workSpace`, which must be a table of >= 1024 unsigned */ +size_t HUF_compress4X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ + +/* *** Dependencies *** */ +#include "mem.h" /* U32 */ + +/* *** Constants *** */ +#define HUF_TABLELOG_MAX 12 /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */ +#define HUF_TABLELOG_DEFAULT 11 /* tableLog by default, when not specified */ +#define HUF_SYMBOLVALUE_MAX 255 + +#define HUF_TABLELOG_ABSOLUTEMAX 15 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */ +#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX) +#error "HUF_TABLELOG_MAX is too large !" +#endif + +/* **************************************** +* Static allocation +******************************************/ +/* HUF buffer bounds */ +#define HUF_CTABLEBOUND 129 +#define HUF_BLOCKBOUND(size) (size + (size >> 8) + 8) /* only true if incompressible pre-filtered with fast heuristic */ +#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */ + +/* static allocation of HUF's Compression Table */ +#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \ + U32 name##hb[maxSymbolValue + 1]; \ + void *name##hv = &(name##hb); \ + HUF_CElt *name = (HUF_CElt *)(name##hv) /* no final ; */ + +/* static allocation of HUF's DTable */ +typedef U32 HUF_DTable; +#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1 << (maxTableLog))) +#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = {((U32)((maxTableLog)-1) * 0x01000001)} +#define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = {((U32)(maxTableLog)*0x01000001)} + +/* The workspace must have alignment at least 4 and be at least this large */ +#define HUF_COMPRESS_WORKSPACE_SIZE (6 << 10) +#define HUF_COMPRESS_WORKSPACE_SIZE_U32 (HUF_COMPRESS_WORKSPACE_SIZE / sizeof(U32)) + +/* The workspace must have alignment at least 4 and be at least this large */ +#define HUF_DECOMPRESS_WORKSPACE_SIZE (3 << 10) +#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32)) + +/* **************************************** +* Advanced decompression functions +******************************************/ +size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); /**< decodes RLE and uncompressed */ +size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< considers RLE and uncompressed as errors */ +size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< single-symbol decoder */ +size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< double-symbols decoder */ + +/* **************************************** +* HUF detailed API +******************************************/ +/*! +HUF_compress() does the following: +1. count symbol occurrence from source[] into table count[] using FSE_count() +2. (optional) refine tableLog using HUF_optimalTableLog() +3. build Huffman table from count using HUF_buildCTable() +4. save Huffman table to memory buffer using HUF_writeCTable_wksp() +5. encode the data stream using HUF_compress4X_usingCTable() + +The following API allows targeting specific sub-functions for advanced tasks. +For example, it's possible to compress several blocks using the same 'CTable', +or to save and regenerate 'CTable' using external methods. +*/ +/* FSE_count() : find it within "fse.h" */ +unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue); +typedef struct HUF_CElt_s HUF_CElt; /* incomplete type */ +size_t HUF_writeCTable_wksp(void *dst, size_t maxDstSize, const HUF_CElt *CTable, unsigned maxSymbolValue, unsigned huffLog, void *workspace, size_t workspaceSize); +size_t HUF_compress4X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable); + +typedef enum { + HUF_repeat_none, /**< Cannot use the previous table */ + HUF_repeat_check, /**< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1, + 4}X_repeat */ + HUF_repeat_valid /**< Can use the previous table and it is asumed to be valid */ +} HUF_repeat; +/** HUF_compress4X_repeat() : +* Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none. +* If it uses hufTable it does not modify hufTable or repeat. +* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used. +* If preferRepeat then the old table will always be used if valid. */ +size_t HUF_compress4X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, + int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ + +/** HUF_buildCTable_wksp() : + * Same as HUF_buildCTable(), but using externally allocated scratch buffer. + * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of 1024 unsigned. + */ +size_t HUF_buildCTable_wksp(HUF_CElt *tree, const U32 *count, U32 maxSymbolValue, U32 maxNbBits, void *workSpace, size_t wkspSize); + +/*! HUF_readStats() : + Read compact Huffman tree, saved by HUF_writeCTable(). + `huffWeight` is destination buffer. + @return : size read from `src` , or an error Code . + Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */ +size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, + void *workspace, size_t workspaceSize); + +/** HUF_readCTable() : +* Loading a CTable saved with HUF_writeCTable() */ +size_t HUF_readCTable_wksp(HUF_CElt *CTable, unsigned maxSymbolValue, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); + +/* +HUF_decompress() does the following: +1. select the decompression algorithm (X2, X4) based on pre-computed heuristics +2. build Huffman table from save, using HUF_readDTableXn() +3. decode 1 or 4 segments in parallel using HUF_decompressSXn_usingDTable +*/ + +/** HUF_selectDecoder() : +* Tells which decoder is likely to decode faster, +* based on a set of pre-determined metrics. +* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 . +* Assumption : 0 < cSrcSize < dstSize <= 128 KB */ +U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize); + +size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); +size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); + +size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); +size_t HUF_decompress4X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); +size_t HUF_decompress4X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); + +/* single stream variants */ + +size_t HUF_compress1X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ +size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable); +/** HUF_compress1X_repeat() : +* Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none. +* If it uses hufTable it does not modify hufTable or repeat. +* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used. +* If preferRepeat then the old table will always be used if valid. */ +size_t HUF_compress1X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, + int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ + +size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); +size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< single-symbol decoder */ +size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< double-symbols decoder */ + +size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, + const HUF_DTable *DTable); /**< automatic selection of sing or double symbol decoder, based on DTable */ +size_t HUF_decompress1X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); +size_t HUF_decompress1X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); + +#endif /* HUF_H_298734234 */ diff --git a/lib/zstd/huf_compress.c b/lib/zstd/huf_compress.c new file mode 100644 index 000000000000..40055a7016e6 --- /dev/null +++ b/lib/zstd/huf_compress.c @@ -0,0 +1,770 @@ +/* + * Huffman encoder, part of New Generation Entropy library + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************************************** +* Includes +****************************************************************/ +#include "bitstream.h" +#include "fse.h" /* header compression */ +#include "huf.h" +#include <linux/kernel.h> +#include <linux/string.h> /* memcpy, memset */ + +/* ************************************************************** +* Error Management +****************************************************************/ +#define HUF_STATIC_ASSERT(c) \ + { \ + enum { HUF_static_assert = 1 / (int)(!!(c)) }; \ + } /* use only *after* variable declarations */ +#define CHECK_V_F(e, f) \ + size_t const e = f; \ + if (ERR_isError(e)) \ + return f +#define CHECK_F(f) \ + { \ + CHECK_V_F(_var_err__, f); \ + } + +/* ************************************************************** +* Utils +****************************************************************/ +unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue) +{ + return FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 1); +} + +/* ******************************************************* +* HUF : Huffman block compression +*********************************************************/ +/* HUF_compressWeights() : + * Same as FSE_compress(), but dedicated to huff0's weights compression. + * The use case needs much less stack memory. + * Note : all elements within weightTable are supposed to be <= HUF_TABLELOG_MAX. + */ +#define MAX_FSE_TABLELOG_FOR_HUFF_HEADER 6 +size_t HUF_compressWeights_wksp(void *dst, size_t dstSize, const void *weightTable, size_t wtSize, void *workspace, size_t workspaceSize) +{ + BYTE *const ostart = (BYTE *)dst; + BYTE *op = ostart; + BYTE *const oend = ostart + dstSize; + + U32 maxSymbolValue = HUF_TABLELOG_MAX; + U32 tableLog = MAX_FSE_TABLELOG_FOR_HUFF_HEADER; + + FSE_CTable *CTable; + U32 *count; + S16 *norm; + size_t spaceUsed32 = 0; + + HUF_STATIC_ASSERT(sizeof(FSE_CTable) == sizeof(U32)); + + CTable = (FSE_CTable *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += FSE_CTABLE_SIZE_U32(MAX_FSE_TABLELOG_FOR_HUFF_HEADER, HUF_TABLELOG_MAX); + count = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_MAX + 1; + norm = (S16 *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(S16) * (HUF_TABLELOG_MAX + 1), sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + /* init conditions */ + if (wtSize <= 1) + return 0; /* Not compressible */ + + /* Scan input and build symbol stats */ + { + CHECK_V_F(maxCount, FSE_count_simple(count, &maxSymbolValue, weightTable, wtSize)); + if (maxCount == wtSize) + return 1; /* only a single symbol in src : rle */ + if (maxCount == 1) + return 0; /* each symbol present maximum once => not compressible */ + } + + tableLog = FSE_optimalTableLog(tableLog, wtSize, maxSymbolValue); + CHECK_F(FSE_normalizeCount(norm, tableLog, count, wtSize, maxSymbolValue)); + + /* Write table description header */ + { + CHECK_V_F(hSize, FSE_writeNCount(op, oend - op, norm, maxSymbolValue, tableLog)); + op += hSize; + } + + /* Compress */ + CHECK_F(FSE_buildCTable_wksp(CTable, norm, maxSymbolValue, tableLog, workspace, workspaceSize)); + { + CHECK_V_F(cSize, FSE_compress_usingCTable(op, oend - op, weightTable, wtSize, CTable)); + if (cSize == 0) + return 0; /* not enough space for compressed data */ + op += cSize; + } + + return op - ostart; +} + +struct HUF_CElt_s { + U16 val; + BYTE nbBits; +}; /* typedef'd to HUF_CElt within "huf.h" */ + +/*! HUF_writeCTable_wksp() : + `CTable` : Huffman tree to save, using huf representation. + @return : size of saved CTable */ +size_t HUF_writeCTable_wksp(void *dst, size_t maxDstSize, const HUF_CElt *CTable, U32 maxSymbolValue, U32 huffLog, void *workspace, size_t workspaceSize) +{ + BYTE *op = (BYTE *)dst; + U32 n; + + BYTE *bitsToWeight; + BYTE *huffWeight; + size_t spaceUsed32 = 0; + + bitsToWeight = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_TABLELOG_MAX + 1, sizeof(U32)) >> 2; + huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + /* check conditions */ + if (maxSymbolValue > HUF_SYMBOLVALUE_MAX) + return ERROR(maxSymbolValue_tooLarge); + + /* convert to weight */ + bitsToWeight[0] = 0; + for (n = 1; n < huffLog + 1; n++) + bitsToWeight[n] = (BYTE)(huffLog + 1 - n); + for (n = 0; n < maxSymbolValue; n++) + huffWeight[n] = bitsToWeight[CTable[n].nbBits]; + + /* attempt weights compression by FSE */ + { + CHECK_V_F(hSize, HUF_compressWeights_wksp(op + 1, maxDstSize - 1, huffWeight, maxSymbolValue, workspace, workspaceSize)); + if ((hSize > 1) & (hSize < maxSymbolValue / 2)) { /* FSE compressed */ + op[0] = (BYTE)hSize; + return hSize + 1; + } + } + + /* write raw values as 4-bits (max : 15) */ + if (maxSymbolValue > (256 - 128)) + return ERROR(GENERIC); /* should not happen : likely means source cannot be compressed */ + if (((maxSymbolValue + 1) / 2) + 1 > maxDstSize) + return ERROR(dstSize_tooSmall); /* not enough space within dst buffer */ + op[0] = (BYTE)(128 /*special case*/ + (maxSymbolValue - 1)); + huffWeight[maxSymbolValue] = 0; /* to be sure it doesn't cause msan issue in final combination */ + for (n = 0; n < maxSymbolValue; n += 2) + op[(n / 2) + 1] = (BYTE)((huffWeight[n] << 4) + huffWeight[n + 1]); + return ((maxSymbolValue + 1) / 2) + 1; +} + +size_t HUF_readCTable_wksp(HUF_CElt *CTable, U32 maxSymbolValue, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 *rankVal; + BYTE *huffWeight; + U32 tableLog = 0; + U32 nbSymbols = 0; + size_t readSize; + size_t spaceUsed32 = 0; + + rankVal = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1; + huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + /* get symbol weights */ + readSize = HUF_readStats_wksp(huffWeight, HUF_SYMBOLVALUE_MAX + 1, rankVal, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize); + if (ERR_isError(readSize)) + return readSize; + + /* check result */ + if (tableLog > HUF_TABLELOG_MAX) + return ERROR(tableLog_tooLarge); + if (nbSymbols > maxSymbolValue + 1) + return ERROR(maxSymbolValue_tooSmall); + + /* Prepare base value per rank */ + { + U32 n, nextRankStart = 0; + for (n = 1; n <= tableLog; n++) { + U32 curr = nextRankStart; + nextRankStart += (rankVal[n] << (n - 1)); + rankVal[n] = curr; + } + } + + /* fill nbBits */ + { + U32 n; + for (n = 0; n < nbSymbols; n++) { + const U32 w = huffWeight[n]; + CTable[n].nbBits = (BYTE)(tableLog + 1 - w); + } + } + + /* fill val */ + { + U16 nbPerRank[HUF_TABLELOG_MAX + 2] = {0}; /* support w=0=>n=tableLog+1 */ + U16 valPerRank[HUF_TABLELOG_MAX + 2] = {0}; + { + U32 n; + for (n = 0; n < nbSymbols; n++) + nbPerRank[CTable[n].nbBits]++; + } + /* determine stating value per rank */ + valPerRank[tableLog + 1] = 0; /* for w==0 */ + { + U16 min = 0; + U32 n; + for (n = tableLog; n > 0; n--) { /* start at n=tablelog <-> w=1 */ + valPerRank[n] = min; /* get starting value within each rank */ + min += nbPerRank[n]; + min >>= 1; + } + } + /* assign value within rank, symbol order */ + { + U32 n; + for (n = 0; n <= maxSymbolValue; n++) + CTable[n].val = valPerRank[CTable[n].nbBits]++; + } + } + + return readSize; +} + +typedef struct nodeElt_s { + U32 count; + U16 parent; + BYTE byte; + BYTE nbBits; +} nodeElt; + +static U32 HUF_setMaxHeight(nodeElt *huffNode, U32 lastNonNull, U32 maxNbBits) +{ + const U32 largestBits = huffNode[lastNonNull].nbBits; + if (largestBits <= maxNbBits) + return largestBits; /* early exit : no elt > maxNbBits */ + + /* there are several too large elements (at least >= 2) */ + { + int totalCost = 0; + const U32 baseCost = 1 << (largestBits - maxNbBits); + U32 n = lastNonNull; + + while (huffNode[n].nbBits > maxNbBits) { + totalCost += baseCost - (1 << (largestBits - huffNode[n].nbBits)); + huffNode[n].nbBits = (BYTE)maxNbBits; + n--; + } /* n stops at huffNode[n].nbBits <= maxNbBits */ + while (huffNode[n].nbBits == maxNbBits) + n--; /* n end at index of smallest symbol using < maxNbBits */ + + /* renorm totalCost */ + totalCost >>= (largestBits - maxNbBits); /* note : totalCost is necessarily a multiple of baseCost */ + + /* repay normalized cost */ + { + U32 const noSymbol = 0xF0F0F0F0; + U32 rankLast[HUF_TABLELOG_MAX + 2]; + int pos; + + /* Get pos of last (smallest) symbol per rank */ + memset(rankLast, 0xF0, sizeof(rankLast)); + { + U32 currNbBits = maxNbBits; + for (pos = n; pos >= 0; pos--) { + if (huffNode[pos].nbBits >= currNbBits) + continue; + currNbBits = huffNode[pos].nbBits; /* < maxNbBits */ + rankLast[maxNbBits - currNbBits] = pos; + } + } + + while (totalCost > 0) { + U32 nBitsToDecrease = BIT_highbit32(totalCost) + 1; + for (; nBitsToDecrease > 1; nBitsToDecrease--) { + U32 highPos = rankLast[nBitsToDecrease]; + U32 lowPos = rankLast[nBitsToDecrease - 1]; + if (highPos == noSymbol) + continue; + if (lowPos == noSymbol) + break; + { + U32 const highTotal = huffNode[highPos].count; + U32 const lowTotal = 2 * huffNode[lowPos].count; + if (highTotal <= lowTotal) + break; + } + } + /* only triggered when no more rank 1 symbol left => find closest one (note : there is necessarily at least one !) */ + /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */ + while ((nBitsToDecrease <= HUF_TABLELOG_MAX) && (rankLast[nBitsToDecrease] == noSymbol)) + nBitsToDecrease++; + totalCost -= 1 << (nBitsToDecrease - 1); + if (rankLast[nBitsToDecrease - 1] == noSymbol) + rankLast[nBitsToDecrease - 1] = rankLast[nBitsToDecrease]; /* this rank is no longer empty */ + huffNode[rankLast[nBitsToDecrease]].nbBits++; + if (rankLast[nBitsToDecrease] == 0) /* special case, reached largest symbol */ + rankLast[nBitsToDecrease] = noSymbol; + else { + rankLast[nBitsToDecrease]--; + if (huffNode[rankLast[nBitsToDecrease]].nbBits != maxNbBits - nBitsToDecrease) + rankLast[nBitsToDecrease] = noSymbol; /* this rank is now empty */ + } + } /* while (totalCost > 0) */ + + while (totalCost < 0) { /* Sometimes, cost correction overshoot */ + if (rankLast[1] == noSymbol) { /* special case : no rank 1 symbol (using maxNbBits-1); let's create one from largest rank 0 + (using maxNbBits) */ + while (huffNode[n].nbBits == maxNbBits) + n--; + huffNode[n + 1].nbBits--; + rankLast[1] = n + 1; + totalCost++; + continue; + } + huffNode[rankLast[1] + 1].nbBits--; + rankLast[1]++; + totalCost++; + } + } + } /* there are several too large elements (at least >= 2) */ + + return maxNbBits; +} + +typedef struct { + U32 base; + U32 curr; +} rankPos; + +static void HUF_sort(nodeElt *huffNode, const U32 *count, U32 maxSymbolValue) +{ + rankPos rank[32]; + U32 n; + + memset(rank, 0, sizeof(rank)); + for (n = 0; n <= maxSymbolValue; n++) { + U32 r = BIT_highbit32(count[n] + 1); + rank[r].base++; + } + for (n = 30; n > 0; n--) + rank[n - 1].base += rank[n].base; + for (n = 0; n < 32; n++) + rank[n].curr = rank[n].base; + for (n = 0; n <= maxSymbolValue; n++) { + U32 const c = count[n]; + U32 const r = BIT_highbit32(c + 1) + 1; + U32 pos = rank[r].curr++; + while ((pos > rank[r].base) && (c > huffNode[pos - 1].count)) + huffNode[pos] = huffNode[pos - 1], pos--; + huffNode[pos].count = c; + huffNode[pos].byte = (BYTE)n; + } +} + +/** HUF_buildCTable_wksp() : + * Same as HUF_buildCTable(), but using externally allocated scratch buffer. + * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of 1024 unsigned. + */ +#define STARTNODE (HUF_SYMBOLVALUE_MAX + 1) +typedef nodeElt huffNodeTable[2 * HUF_SYMBOLVALUE_MAX + 1 + 1]; +size_t HUF_buildCTable_wksp(HUF_CElt *tree, const U32 *count, U32 maxSymbolValue, U32 maxNbBits, void *workSpace, size_t wkspSize) +{ + nodeElt *const huffNode0 = (nodeElt *)workSpace; + nodeElt *const huffNode = huffNode0 + 1; + U32 n, nonNullRank; + int lowS, lowN; + U16 nodeNb = STARTNODE; + U32 nodeRoot; + + /* safety checks */ + if (wkspSize < sizeof(huffNodeTable)) + return ERROR(GENERIC); /* workSpace is not large enough */ + if (maxNbBits == 0) + maxNbBits = HUF_TABLELOG_DEFAULT; + if (maxSymbolValue > HUF_SYMBOLVALUE_MAX) + return ERROR(GENERIC); + memset(huffNode0, 0, sizeof(huffNodeTable)); + + /* sort, decreasing order */ + HUF_sort(huffNode, count, maxSymbolValue); + + /* init for parents */ + nonNullRank = maxSymbolValue; + while (huffNode[nonNullRank].count == 0) + nonNullRank--; + lowS = nonNullRank; + nodeRoot = nodeNb + lowS - 1; + lowN = nodeNb; + huffNode[nodeNb].count = huffNode[lowS].count + huffNode[lowS - 1].count; + huffNode[lowS].parent = huffNode[lowS - 1].parent = nodeNb; + nodeNb++; + lowS -= 2; + for (n = nodeNb; n <= nodeRoot; n++) + huffNode[n].count = (U32)(1U << 30); + huffNode0[0].count = (U32)(1U << 31); /* fake entry, strong barrier */ + + /* create parents */ + while (nodeNb <= nodeRoot) { + U32 n1 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++; + U32 n2 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++; + huffNode[nodeNb].count = huffNode[n1].count + huffNode[n2].count; + huffNode[n1].parent = huffNode[n2].parent = nodeNb; + nodeNb++; + } + + /* distribute weights (unlimited tree height) */ + huffNode[nodeRoot].nbBits = 0; + for (n = nodeRoot - 1; n >= STARTNODE; n--) + huffNode[n].nbBits = huffNode[huffNode[n].parent].nbBits + 1; + for (n = 0; n <= nonNullRank; n++) + huffNode[n].nbBits = huffNode[huffNode[n].parent].nbBits + 1; + + /* enforce maxTableLog */ + maxNbBits = HUF_setMaxHeight(huffNode, nonNullRank, maxNbBits); + + /* fill result into tree (val, nbBits) */ + { + U16 nbPerRank[HUF_TABLELOG_MAX + 1] = {0}; + U16 valPerRank[HUF_TABLELOG_MAX + 1] = {0}; + if (maxNbBits > HUF_TABLELOG_MAX) + return ERROR(GENERIC); /* check fit into table */ + for (n = 0; n <= nonNullRank; n++) + nbPerRank[huffNode[n].nbBits]++; + /* determine stating value per rank */ + { + U16 min = 0; + for (n = maxNbBits; n > 0; n--) { + valPerRank[n] = min; /* get starting value within each rank */ + min += nbPerRank[n]; + min >>= 1; + } + } + for (n = 0; n <= maxSymbolValue; n++) + tree[huffNode[n].byte].nbBits = huffNode[n].nbBits; /* push nbBits per symbol, symbol order */ + for (n = 0; n <= maxSymbolValue; n++) + tree[n].val = valPerRank[tree[n].nbBits]++; /* assign value within rank, symbol order */ + } + + return maxNbBits; +} + +static size_t HUF_estimateCompressedSize(HUF_CElt *CTable, const unsigned *count, unsigned maxSymbolValue) +{ + size_t nbBits = 0; + int s; + for (s = 0; s <= (int)maxSymbolValue; ++s) { + nbBits += CTable[s].nbBits * count[s]; + } + return nbBits >> 3; +} + +static int HUF_validateCTable(const HUF_CElt *CTable, const unsigned *count, unsigned maxSymbolValue) +{ + int bad = 0; + int s; + for (s = 0; s <= (int)maxSymbolValue; ++s) { + bad |= (count[s] != 0) & (CTable[s].nbBits == 0); + } + return !bad; +} + +static void HUF_encodeSymbol(BIT_CStream_t *bitCPtr, U32 symbol, const HUF_CElt *CTable) +{ + BIT_addBitsFast(bitCPtr, CTable[symbol].val, CTable[symbol].nbBits); +} + +size_t HUF_compressBound(size_t size) { return HUF_COMPRESSBOUND(size); } + +#define HUF_FLUSHBITS(s) BIT_flushBits(s) + +#define HUF_FLUSHBITS_1(stream) \ + if (sizeof((stream)->bitContainer) * 8 < HUF_TABLELOG_MAX * 2 + 7) \ + HUF_FLUSHBITS(stream) + +#define HUF_FLUSHBITS_2(stream) \ + if (sizeof((stream)->bitContainer) * 8 < HUF_TABLELOG_MAX * 4 + 7) \ + HUF_FLUSHBITS(stream) + +size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable) +{ + const BYTE *ip = (const BYTE *)src; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + BYTE *op = ostart; + size_t n; + BIT_CStream_t bitC; + + /* init */ + if (dstSize < 8) + return 0; /* not enough space to compress */ + { + size_t const initErr = BIT_initCStream(&bitC, op, oend - op); + if (HUF_isError(initErr)) + return 0; + } + + n = srcSize & ~3; /* join to mod 4 */ + switch (srcSize & 3) { + case 3: HUF_encodeSymbol(&bitC, ip[n + 2], CTable); HUF_FLUSHBITS_2(&bitC); + case 2: HUF_encodeSymbol(&bitC, ip[n + 1], CTable); HUF_FLUSHBITS_1(&bitC); + case 1: HUF_encodeSymbol(&bitC, ip[n + 0], CTable); HUF_FLUSHBITS(&bitC); + case 0: + default:; + } + + for (; n > 0; n -= 4) { /* note : n&3==0 at this stage */ + HUF_encodeSymbol(&bitC, ip[n - 1], CTable); + HUF_FLUSHBITS_1(&bitC); + HUF_encodeSymbol(&bitC, ip[n - 2], CTable); + HUF_FLUSHBITS_2(&bitC); + HUF_encodeSymbol(&bitC, ip[n - 3], CTable); + HUF_FLUSHBITS_1(&bitC); + HUF_encodeSymbol(&bitC, ip[n - 4], CTable); + HUF_FLUSHBITS(&bitC); + } + + return BIT_closeCStream(&bitC); +} + +size_t HUF_compress4X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable) +{ + size_t const segmentSize = (srcSize + 3) / 4; /* first 3 segments */ + const BYTE *ip = (const BYTE *)src; + const BYTE *const iend = ip + srcSize; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + BYTE *op = ostart; + + if (dstSize < 6 + 1 + 1 + 1 + 8) + return 0; /* minimum space to compress successfully */ + if (srcSize < 12) + return 0; /* no saving possible : too small input */ + op += 6; /* jumpTable */ + + { + CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, segmentSize, CTable)); + if (cSize == 0) + return 0; + ZSTD_writeLE16(ostart, (U16)cSize); + op += cSize; + } + + ip += segmentSize; + { + CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, segmentSize, CTable)); + if (cSize == 0) + return 0; + ZSTD_writeLE16(ostart + 2, (U16)cSize); + op += cSize; + } + + ip += segmentSize; + { + CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, segmentSize, CTable)); + if (cSize == 0) + return 0; + ZSTD_writeLE16(ostart + 4, (U16)cSize); + op += cSize; + } + + ip += segmentSize; + { + CHECK_V_F(cSize, HUF_compress1X_usingCTable(op, oend - op, ip, iend - ip, CTable)); + if (cSize == 0) + return 0; + op += cSize; + } + + return op - ostart; +} + +static size_t HUF_compressCTable_internal(BYTE *const ostart, BYTE *op, BYTE *const oend, const void *src, size_t srcSize, unsigned singleStream, + const HUF_CElt *CTable) +{ + size_t const cSize = + singleStream ? HUF_compress1X_usingCTable(op, oend - op, src, srcSize, CTable) : HUF_compress4X_usingCTable(op, oend - op, src, srcSize, CTable); + if (HUF_isError(cSize)) { + return cSize; + } + if (cSize == 0) { + return 0; + } /* uncompressible */ + op += cSize; + /* check compressibility */ + if ((size_t)(op - ostart) >= srcSize - 1) { + return 0; + } + return op - ostart; +} + +/* `workSpace` must a table of at least 1024 unsigned */ +static size_t HUF_compress_internal(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, + unsigned singleStream, void *workSpace, size_t wkspSize, HUF_CElt *oldHufTable, HUF_repeat *repeat, int preferRepeat) +{ + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + BYTE *op = ostart; + + U32 *count; + size_t const countSize = sizeof(U32) * (HUF_SYMBOLVALUE_MAX + 1); + HUF_CElt *CTable; + size_t const CTableSize = sizeof(HUF_CElt) * (HUF_SYMBOLVALUE_MAX + 1); + + /* checks & inits */ + if (wkspSize < sizeof(huffNodeTable) + countSize + CTableSize) + return ERROR(GENERIC); + if (!srcSize) + return 0; /* Uncompressed (note : 1 means rle, so first byte must be correct) */ + if (!dstSize) + return 0; /* cannot fit within dst budget */ + if (srcSize > HUF_BLOCKSIZE_MAX) + return ERROR(srcSize_wrong); /* curr block size limit */ + if (huffLog > HUF_TABLELOG_MAX) + return ERROR(tableLog_tooLarge); + if (!maxSymbolValue) + maxSymbolValue = HUF_SYMBOLVALUE_MAX; + if (!huffLog) + huffLog = HUF_TABLELOG_DEFAULT; + + count = (U32 *)workSpace; + workSpace = (BYTE *)workSpace + countSize; + wkspSize -= countSize; + CTable = (HUF_CElt *)workSpace; + workSpace = (BYTE *)workSpace + CTableSize; + wkspSize -= CTableSize; + + /* Heuristic : If we don't need to check the validity of the old table use the old table for small inputs */ + if (preferRepeat && repeat && *repeat == HUF_repeat_valid) { + return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, oldHufTable); + } + + /* Scan input and build symbol stats */ + { + CHECK_V_F(largest, FSE_count_wksp(count, &maxSymbolValue, (const BYTE *)src, srcSize, (U32 *)workSpace)); + if (largest == srcSize) { + *ostart = ((const BYTE *)src)[0]; + return 1; + } /* single symbol, rle */ + if (largest <= (srcSize >> 7) + 1) + return 0; /* Fast heuristic : not compressible enough */ + } + + /* Check validity of previous table */ + if (repeat && *repeat == HUF_repeat_check && !HUF_validateCTable(oldHufTable, count, maxSymbolValue)) { + *repeat = HUF_repeat_none; + } + /* Heuristic : use existing table for small inputs */ + if (preferRepeat && repeat && *repeat != HUF_repeat_none) { + return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, oldHufTable); + } + + /* Build Huffman Tree */ + huffLog = HUF_optimalTableLog(huffLog, srcSize, maxSymbolValue); + { + CHECK_V_F(maxBits, HUF_buildCTable_wksp(CTable, count, maxSymbolValue, huffLog, workSpace, wkspSize)); + huffLog = (U32)maxBits; + /* Zero the unused symbols so we can check it for validity */ + memset(CTable + maxSymbolValue + 1, 0, CTableSize - (maxSymbolValue + 1) * sizeof(HUF_CElt)); + } + + /* Write table description header */ + { + CHECK_V_F(hSize, HUF_writeCTable_wksp(op, dstSize, CTable, maxSymbolValue, huffLog, workSpace, wkspSize)); + /* Check if using the previous table will be beneficial */ + if (repeat && *repeat != HUF_repeat_none) { + size_t const oldSize = HUF_estimateCompressedSize(oldHufTable, count, maxSymbolValue); + size_t const newSize = HUF_estimateCompressedSize(CTable, count, maxSymbolValue); + if (oldSize <= hSize + newSize || hSize + 12 >= srcSize) { + return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, oldHufTable); + } + } + /* Use the new table */ + if (hSize + 12ul >= srcSize) { + return 0; + } + op += hSize; + if (repeat) { + *repeat = HUF_repeat_none; + } + if (oldHufTable) { + memcpy(oldHufTable, CTable, CTableSize); + } /* Save the new table */ + } + return HUF_compressCTable_internal(ostart, op, oend, src, srcSize, singleStream, CTable); +} + +size_t HUF_compress1X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace, + size_t wkspSize) +{ + return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 1 /* single stream */, workSpace, wkspSize, NULL, NULL, 0); +} + +size_t HUF_compress1X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace, + size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, int preferRepeat) +{ + return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 1 /* single stream */, workSpace, wkspSize, hufTable, repeat, + preferRepeat); +} + +size_t HUF_compress4X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace, + size_t wkspSize) +{ + return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 0 /* 4 streams */, workSpace, wkspSize, NULL, NULL, 0); +} + +size_t HUF_compress4X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned huffLog, void *workSpace, + size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, int preferRepeat) +{ + return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 0 /* 4 streams */, workSpace, wkspSize, hufTable, repeat, + preferRepeat); +} diff --git a/lib/zstd/huf_decompress.c b/lib/zstd/huf_decompress.c new file mode 100644 index 000000000000..6526482047dc --- /dev/null +++ b/lib/zstd/huf_decompress.c @@ -0,0 +1,960 @@ +/* + * Huffman decoder, part of New Generation Entropy library + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************************************** +* Compiler specifics +****************************************************************/ +#define FORCE_INLINE static __always_inline + +/* ************************************************************** +* Dependencies +****************************************************************/ +#include "bitstream.h" /* BIT_* */ +#include "fse.h" /* header compression */ +#include "huf.h" +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/string.h> /* memcpy, memset */ + +/* ************************************************************** +* Error Management +****************************************************************/ +#define HUF_STATIC_ASSERT(c) \ + { \ + enum { HUF_static_assert = 1 / (int)(!!(c)) }; \ + } /* use only *after* variable declarations */ + +/*-***************************/ +/* generic DTableDesc */ +/*-***************************/ + +typedef struct { + BYTE maxTableLog; + BYTE tableType; + BYTE tableLog; + BYTE reserved; +} DTableDesc; + +static DTableDesc HUF_getDTableDesc(const HUF_DTable *table) +{ + DTableDesc dtd; + memcpy(&dtd, table, sizeof(dtd)); + return dtd; +} + +/*-***************************/ +/* single-symbol decoding */ +/*-***************************/ + +typedef struct { + BYTE byte; + BYTE nbBits; +} HUF_DEltX2; /* single-symbol decoding */ + +size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 tableLog = 0; + U32 nbSymbols = 0; + size_t iSize; + void *const dtPtr = DTable + 1; + HUF_DEltX2 *const dt = (HUF_DEltX2 *)dtPtr; + + U32 *rankVal; + BYTE *huffWeight; + size_t spaceUsed32 = 0; + + rankVal = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1; + huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + HUF_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable)); + /* memset(huffWeight, 0, sizeof(huffWeight)); */ /* is not necessary, even though some analyzer complain ... */ + + iSize = HUF_readStats_wksp(huffWeight, HUF_SYMBOLVALUE_MAX + 1, rankVal, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize); + if (HUF_isError(iSize)) + return iSize; + + /* Table header */ + { + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (tableLog > (U32)(dtd.maxTableLog + 1)) + return ERROR(tableLog_tooLarge); /* DTable too small, Huffman tree cannot fit in */ + dtd.tableType = 0; + dtd.tableLog = (BYTE)tableLog; + memcpy(DTable, &dtd, sizeof(dtd)); + } + + /* Calculate starting value for each rank */ + { + U32 n, nextRankStart = 0; + for (n = 1; n < tableLog + 1; n++) { + U32 const curr = nextRankStart; + nextRankStart += (rankVal[n] << (n - 1)); + rankVal[n] = curr; + } + } + + /* fill DTable */ + { + U32 n; + for (n = 0; n < nbSymbols; n++) { + U32 const w = huffWeight[n]; + U32 const length = (1 << w) >> 1; + U32 u; + HUF_DEltX2 D; + D.byte = (BYTE)n; + D.nbBits = (BYTE)(tableLog + 1 - w); + for (u = rankVal[w]; u < rankVal[w] + length; u++) + dt[u] = D; + rankVal[w] += length; + } + } + + return iSize; +} + +static BYTE HUF_decodeSymbolX2(BIT_DStream_t *Dstream, const HUF_DEltX2 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */ + BYTE const c = dt[val].byte; + BIT_skipBits(Dstream, dt[val].nbBits); + return c; +} + +#define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) *ptr++ = HUF_decodeSymbolX2(DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \ + if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \ + HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) + +#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \ + if (ZSTD_64bits()) \ + HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) + +FORCE_INLINE size_t HUF_decodeStreamX2(BYTE *p, BIT_DStream_t *const bitDPtr, BYTE *const pEnd, const HUF_DEltX2 *const dt, const U32 dtLog) +{ + BYTE *const pStart = p; + + /* up to 4 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p <= pEnd - 4)) { + HUF_DECODE_SYMBOLX2_2(p, bitDPtr); + HUF_DECODE_SYMBOLX2_1(p, bitDPtr); + HUF_DECODE_SYMBOLX2_2(p, bitDPtr); + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + } + + /* closer to the end */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p < pEnd)) + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + + /* no more data to retrieve from bitstream, hence no need to reload */ + while (p < pEnd) + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + + return pEnd - pStart; +} + +static size_t HUF_decompress1X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + BYTE *op = (BYTE *)dst; + BYTE *const oend = op + dstSize; + const void *dtPtr = DTable + 1; + const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr; + BIT_DStream_t bitD; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + { + size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize); + if (HUF_isError(errorCode)) + return errorCode; + } + + HUF_decodeStreamX2(op, &bitD, oend, dt, dtLog); + + /* check */ + if (!BIT_endOfDStream(&bitD)) + return ERROR(corruption_detected); + + return dstSize; +} + +size_t HUF_decompress1X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 0) + return ERROR(GENERIC); + return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress1X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx); +} + +static size_t HUF_decompress4X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + /* Check */ + if (cSrcSize < 10) + return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */ + + { + const BYTE *const istart = (const BYTE *)cSrc; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; + const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr; + + /* Init */ + BIT_DStream_t bitD1; + BIT_DStream_t bitD2; + BIT_DStream_t bitD3; + BIT_DStream_t bitD4; + size_t const length1 = ZSTD_readLE16(istart); + size_t const length2 = ZSTD_readLE16(istart + 2); + size_t const length3 = ZSTD_readLE16(istart + 4); + size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6); + const BYTE *const istart1 = istart + 6; /* jumpTable */ + const BYTE *const istart2 = istart1 + length1; + const BYTE *const istart3 = istart2 + length2; + const BYTE *const istart4 = istart3 + length3; + const size_t segmentSize = (dstSize + 3) / 4; + BYTE *const opStart2 = ostart + segmentSize; + BYTE *const opStart3 = opStart2 + segmentSize; + BYTE *const opStart4 = opStart3 + segmentSize; + BYTE *op1 = ostart; + BYTE *op2 = opStart2; + BYTE *op3 = opStart3; + BYTE *op4 = opStart4; + U32 endSignal; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + if (length4 > cSrcSize) + return ERROR(corruption_detected); /* overflow */ + { + size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* 16-32 symbols per loop (4-8 symbols per stream) */ + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + for (; (endSignal == BIT_DStream_unfinished) && (op4 < (oend - 7));) { + HUF_DECODE_SYMBOLX2_2(op1, &bitD1); + HUF_DECODE_SYMBOLX2_2(op2, &bitD2); + HUF_DECODE_SYMBOLX2_2(op3, &bitD3); + HUF_DECODE_SYMBOLX2_2(op4, &bitD4); + HUF_DECODE_SYMBOLX2_1(op1, &bitD1); + HUF_DECODE_SYMBOLX2_1(op2, &bitD2); + HUF_DECODE_SYMBOLX2_1(op3, &bitD3); + HUF_DECODE_SYMBOLX2_1(op4, &bitD4); + HUF_DECODE_SYMBOLX2_2(op1, &bitD1); + HUF_DECODE_SYMBOLX2_2(op2, &bitD2); + HUF_DECODE_SYMBOLX2_2(op3, &bitD3); + HUF_DECODE_SYMBOLX2_2(op4, &bitD4); + HUF_DECODE_SYMBOLX2_0(op1, &bitD1); + HUF_DECODE_SYMBOLX2_0(op2, &bitD2); + HUF_DECODE_SYMBOLX2_0(op3, &bitD3); + HUF_DECODE_SYMBOLX2_0(op4, &bitD4); + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + } + + /* check corruption */ + if (op1 > opStart2) + return ERROR(corruption_detected); + if (op2 > opStart3) + return ERROR(corruption_detected); + if (op3 > opStart4) + return ERROR(corruption_detected); + /* note : op4 supposed already verified within main loop */ + + /* finish bitStreams one by one */ + HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog); + HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog); + HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog); + HUF_decodeStreamX2(op4, &bitD4, oend, dt, dtLog); + + /* check */ + endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4); + if (!endSignal) + return ERROR(corruption_detected); + + /* decoded size */ + return dstSize; + } +} + +size_t HUF_decompress4X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 0) + return ERROR(GENERIC); + return HUF_decompress4X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX2_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress4X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx); +} + +/* *************************/ +/* double-symbols decoding */ +/* *************************/ +typedef struct { + U16 sequence; + BYTE nbBits; + BYTE length; +} HUF_DEltX4; /* double-symbols decoding */ + +typedef struct { + BYTE symbol; + BYTE weight; +} sortedSymbol_t; + +/* HUF_fillDTableX4Level2() : + * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */ +static void HUF_fillDTableX4Level2(HUF_DEltX4 *DTable, U32 sizeLog, const U32 consumed, const U32 *rankValOrigin, const int minWeight, + const sortedSymbol_t *sortedSymbols, const U32 sortedListSize, U32 nbBitsBaseline, U16 baseSeq) +{ + HUF_DEltX4 DElt; + U32 rankVal[HUF_TABLELOG_MAX + 1]; + + /* get pre-calculated rankVal */ + memcpy(rankVal, rankValOrigin, sizeof(rankVal)); + + /* fill skipped values */ + if (minWeight > 1) { + U32 i, skipSize = rankVal[minWeight]; + ZSTD_writeLE16(&(DElt.sequence), baseSeq); + DElt.nbBits = (BYTE)(consumed); + DElt.length = 1; + for (i = 0; i < skipSize; i++) + DTable[i] = DElt; + } + + /* fill DTable */ + { + U32 s; + for (s = 0; s < sortedListSize; s++) { /* note : sortedSymbols already skipped */ + const U32 symbol = sortedSymbols[s].symbol; + const U32 weight = sortedSymbols[s].weight; + const U32 nbBits = nbBitsBaseline - weight; + const U32 length = 1 << (sizeLog - nbBits); + const U32 start = rankVal[weight]; + U32 i = start; + const U32 end = start + length; + + ZSTD_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8))); + DElt.nbBits = (BYTE)(nbBits + consumed); + DElt.length = 2; + do { + DTable[i++] = DElt; + } while (i < end); /* since length >= 1 */ + + rankVal[weight] += length; + } + } +} + +typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1]; +typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1]; + +static void HUF_fillDTableX4(HUF_DEltX4 *DTable, const U32 targetLog, const sortedSymbol_t *sortedList, const U32 sortedListSize, const U32 *rankStart, + rankVal_t rankValOrigin, const U32 maxWeight, const U32 nbBitsBaseline) +{ + U32 rankVal[HUF_TABLELOG_MAX + 1]; + const int scaleLog = nbBitsBaseline - targetLog; /* note : targetLog >= srcLog, hence scaleLog <= 1 */ + const U32 minBits = nbBitsBaseline - maxWeight; + U32 s; + + memcpy(rankVal, rankValOrigin, sizeof(rankVal)); + + /* fill DTable */ + for (s = 0; s < sortedListSize; s++) { + const U16 symbol = sortedList[s].symbol; + const U32 weight = sortedList[s].weight; + const U32 nbBits = nbBitsBaseline - weight; + const U32 start = rankVal[weight]; + const U32 length = 1 << (targetLog - nbBits); + + if (targetLog - nbBits >= minBits) { /* enough room for a second symbol */ + U32 sortedRank; + int minWeight = nbBits + scaleLog; + if (minWeight < 1) + minWeight = 1; + sortedRank = rankStart[minWeight]; + HUF_fillDTableX4Level2(DTable + start, targetLog - nbBits, nbBits, rankValOrigin[nbBits], minWeight, sortedList + sortedRank, + sortedListSize - sortedRank, nbBitsBaseline, symbol); + } else { + HUF_DEltX4 DElt; + ZSTD_writeLE16(&(DElt.sequence), symbol); + DElt.nbBits = (BYTE)(nbBits); + DElt.length = 1; + { + U32 const end = start + length; + U32 u; + for (u = start; u < end; u++) + DTable[u] = DElt; + } + } + rankVal[weight] += length; + } +} + +size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 tableLog, maxW, sizeOfSort, nbSymbols; + DTableDesc dtd = HUF_getDTableDesc(DTable); + U32 const maxTableLog = dtd.maxTableLog; + size_t iSize; + void *dtPtr = DTable + 1; /* force compiler to avoid strict-aliasing */ + HUF_DEltX4 *const dt = (HUF_DEltX4 *)dtPtr; + U32 *rankStart; + + rankValCol_t *rankVal; + U32 *rankStats; + U32 *rankStart0; + sortedSymbol_t *sortedSymbol; + BYTE *weightList; + size_t spaceUsed32 = 0; + + HUF_STATIC_ASSERT((sizeof(rankValCol_t) & 3) == 0); + + rankVal = (rankValCol_t *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += (sizeof(rankValCol_t) * HUF_TABLELOG_MAX) >> 2; + rankStats = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_MAX + 1; + rankStart0 = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_MAX + 2; + sortedSymbol = (sortedSymbol_t *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(sortedSymbol_t) * (HUF_SYMBOLVALUE_MAX + 1), sizeof(U32)) >> 2; + weightList = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + rankStart = rankStart0 + 1; + memset(rankStats, 0, sizeof(U32) * (2 * HUF_TABLELOG_MAX + 2 + 1)); + + HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable)); /* if compiler fails here, assertion is wrong */ + if (maxTableLog > HUF_TABLELOG_MAX) + return ERROR(tableLog_tooLarge); + /* memset(weightList, 0, sizeof(weightList)); */ /* is not necessary, even though some analyzer complain ... */ + + iSize = HUF_readStats_wksp(weightList, HUF_SYMBOLVALUE_MAX + 1, rankStats, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize); + if (HUF_isError(iSize)) + return iSize; + + /* check result */ + if (tableLog > maxTableLog) + return ERROR(tableLog_tooLarge); /* DTable can't fit code depth */ + + /* find maxWeight */ + for (maxW = tableLog; rankStats[maxW] == 0; maxW--) { + } /* necessarily finds a solution before 0 */ + + /* Get start index of each weight */ + { + U32 w, nextRankStart = 0; + for (w = 1; w < maxW + 1; w++) { + U32 curr = nextRankStart; + nextRankStart += rankStats[w]; + rankStart[w] = curr; + } + rankStart[0] = nextRankStart; /* put all 0w symbols at the end of sorted list*/ + sizeOfSort = nextRankStart; + } + + /* sort symbols by weight */ + { + U32 s; + for (s = 0; s < nbSymbols; s++) { + U32 const w = weightList[s]; + U32 const r = rankStart[w]++; + sortedSymbol[r].symbol = (BYTE)s; + sortedSymbol[r].weight = (BYTE)w; + } + rankStart[0] = 0; /* forget 0w symbols; this is beginning of weight(1) */ + } + + /* Build rankVal */ + { + U32 *const rankVal0 = rankVal[0]; + { + int const rescale = (maxTableLog - tableLog) - 1; /* tableLog <= maxTableLog */ + U32 nextRankVal = 0; + U32 w; + for (w = 1; w < maxW + 1; w++) { + U32 curr = nextRankVal; + nextRankVal += rankStats[w] << (w + rescale); + rankVal0[w] = curr; + } + } + { + U32 const minBits = tableLog + 1 - maxW; + U32 consumed; + for (consumed = minBits; consumed < maxTableLog - minBits + 1; consumed++) { + U32 *const rankValPtr = rankVal[consumed]; + U32 w; + for (w = 1; w < maxW + 1; w++) { + rankValPtr[w] = rankVal0[w] >> consumed; + } + } + } + } + + HUF_fillDTableX4(dt, maxTableLog, sortedSymbol, sizeOfSort, rankStart0, rankVal, maxW, tableLog + 1); + + dtd.tableLog = (BYTE)maxTableLog; + dtd.tableType = 1; + memcpy(DTable, &dtd, sizeof(dtd)); + return iSize; +} + +static U32 HUF_decodeSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */ + memcpy(op, dt + val, 2); + BIT_skipBits(DStream, dt[val].nbBits); + return dt[val].length; +} + +static U32 HUF_decodeLastSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */ + memcpy(op, dt + val, 1); + if (dt[val].length == 1) + BIT_skipBits(DStream, dt[val].nbBits); + else { + if (DStream->bitsConsumed < (sizeof(DStream->bitContainer) * 8)) { + BIT_skipBits(DStream, dt[val].nbBits); + if (DStream->bitsConsumed > (sizeof(DStream->bitContainer) * 8)) + /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */ + DStream->bitsConsumed = (sizeof(DStream->bitContainer) * 8); + } + } + return 1; +} + +#define HUF_DECODE_SYMBOLX4_0(ptr, DStreamPtr) ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \ + if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \ + ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \ + if (ZSTD_64bits()) \ + ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +FORCE_INLINE size_t HUF_decodeStreamX4(BYTE *p, BIT_DStream_t *bitDPtr, BYTE *const pEnd, const HUF_DEltX4 *const dt, const U32 dtLog) +{ + BYTE *const pStart = p; + + /* up to 8 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd - (sizeof(bitDPtr->bitContainer) - 1))) { + HUF_DECODE_SYMBOLX4_2(p, bitDPtr); + HUF_DECODE_SYMBOLX4_1(p, bitDPtr); + HUF_DECODE_SYMBOLX4_2(p, bitDPtr); + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); + } + + /* closer to end : up to 2 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd - 2)) + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); + + while (p <= pEnd - 2) + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); /* no need to reload : reached the end of DStream */ + + if (p < pEnd) + p += HUF_decodeLastSymbolX4(p, bitDPtr, dt, dtLog); + + return p - pStart; +} + +static size_t HUF_decompress1X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + BIT_DStream_t bitD; + + /* Init */ + { + size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* decode */ + { + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; /* force compiler to not use strict-aliasing */ + const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + HUF_decodeStreamX4(ostart, &bitD, oend, dt, dtd.tableLog); + } + + /* check */ + if (!BIT_endOfDStream(&bitD)) + return ERROR(corruption_detected); + + /* decoded size */ + return dstSize; +} + +size_t HUF_decompress1X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 1) + return ERROR(GENERIC); + return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress1X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx); +} + +static size_t HUF_decompress4X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + if (cSrcSize < 10) + return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */ + + { + const BYTE *const istart = (const BYTE *)cSrc; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; + const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr; + + /* Init */ + BIT_DStream_t bitD1; + BIT_DStream_t bitD2; + BIT_DStream_t bitD3; + BIT_DStream_t bitD4; + size_t const length1 = ZSTD_readLE16(istart); + size_t const length2 = ZSTD_readLE16(istart + 2); + size_t const length3 = ZSTD_readLE16(istart + 4); + size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6); + const BYTE *const istart1 = istart + 6; /* jumpTable */ + const BYTE *const istart2 = istart1 + length1; + const BYTE *const istart3 = istart2 + length2; + const BYTE *const istart4 = istart3 + length3; + size_t const segmentSize = (dstSize + 3) / 4; + BYTE *const opStart2 = ostart + segmentSize; + BYTE *const opStart3 = opStart2 + segmentSize; + BYTE *const opStart4 = opStart3 + segmentSize; + BYTE *op1 = ostart; + BYTE *op2 = opStart2; + BYTE *op3 = opStart3; + BYTE *op4 = opStart4; + U32 endSignal; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + if (length4 > cSrcSize) + return ERROR(corruption_detected); /* overflow */ + { + size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* 16-32 symbols per loop (4-8 symbols per stream) */ + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + for (; (endSignal == BIT_DStream_unfinished) & (op4 < (oend - (sizeof(bitD4.bitContainer) - 1)));) { + HUF_DECODE_SYMBOLX4_2(op1, &bitD1); + HUF_DECODE_SYMBOLX4_2(op2, &bitD2); + HUF_DECODE_SYMBOLX4_2(op3, &bitD3); + HUF_DECODE_SYMBOLX4_2(op4, &bitD4); + HUF_DECODE_SYMBOLX4_1(op1, &bitD1); + HUF_DECODE_SYMBOLX4_1(op2, &bitD2); + HUF_DECODE_SYMBOLX4_1(op3, &bitD3); + HUF_DECODE_SYMBOLX4_1(op4, &bitD4); + HUF_DECODE_SYMBOLX4_2(op1, &bitD1); + HUF_DECODE_SYMBOLX4_2(op2, &bitD2); + HUF_DECODE_SYMBOLX4_2(op3, &bitD3); + HUF_DECODE_SYMBOLX4_2(op4, &bitD4); + HUF_DECODE_SYMBOLX4_0(op1, &bitD1); + HUF_DECODE_SYMBOLX4_0(op2, &bitD2); + HUF_DECODE_SYMBOLX4_0(op3, &bitD3); + HUF_DECODE_SYMBOLX4_0(op4, &bitD4); + + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + } + + /* check corruption */ + if (op1 > opStart2) + return ERROR(corruption_detected); + if (op2 > opStart3) + return ERROR(corruption_detected); + if (op3 > opStart4) + return ERROR(corruption_detected); + /* note : op4 already verified within main loop */ + + /* finish bitStreams one by one */ + HUF_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog); + HUF_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog); + HUF_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog); + HUF_decodeStreamX4(op4, &bitD4, oend, dt, dtLog); + + /* check */ + { + U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4); + if (!endCheck) + return ERROR(corruption_detected); + } + + /* decoded size */ + return dstSize; + } +} + +size_t HUF_decompress4X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 1) + return ERROR(GENERIC); + return HUF_decompress4X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx); +} + +/* ********************************/ +/* Generic decompression selector */ +/* ********************************/ + +size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc const dtd = HUF_getDTableDesc(DTable); + return dtd.tableType ? HUF_decompress1X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable) + : HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc const dtd = HUF_getDTableDesc(DTable); + return dtd.tableType ? HUF_decompress4X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable) + : HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable); +} + +typedef struct { + U32 tableTime; + U32 decode256Time; +} algo_time_t; +static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] = { + /* single, double, quad */ + {{0, 0}, {1, 1}, {2, 2}}, /* Q==0 : impossible */ + {{0, 0}, {1, 1}, {2, 2}}, /* Q==1 : impossible */ + {{38, 130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */ + {{448, 128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */ + {{556, 128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */ + {{714, 128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */ + {{883, 128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */ + {{897, 128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */ + {{926, 128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */ + {{947, 128}, {1729, 77}, {3359, 77}}, /* Q == 9 : 56-62% */ + {{1107, 128}, {2083, 81}, {4006, 84}}, /* Q ==10 : 62-69% */ + {{1177, 128}, {2379, 87}, {4785, 88}}, /* Q ==11 : 69-75% */ + {{1242, 128}, {2415, 93}, {5155, 84}}, /* Q ==12 : 75-81% */ + {{1349, 128}, {2644, 106}, {5260, 106}}, /* Q ==13 : 81-87% */ + {{1455, 128}, {2422, 124}, {4174, 124}}, /* Q ==14 : 87-93% */ + {{722, 128}, {1891, 145}, {1936, 146}}, /* Q ==15 : 93-99% */ +}; + +/** HUF_selectDecoder() : +* Tells which decoder is likely to decode faster, +* based on a set of pre-determined metrics. +* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 . +* Assumption : 0 < cSrcSize < dstSize <= 128 KB */ +U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize) +{ + /* decoder timing evaluation */ + U32 const Q = (U32)(cSrcSize * 16 / dstSize); /* Q < 16 since dstSize > cSrcSize */ + U32 const D256 = (U32)(dstSize >> 8); + U32 const DTime0 = algoTime[Q][0].tableTime + (algoTime[Q][0].decode256Time * D256); + U32 DTime1 = algoTime[Q][1].tableTime + (algoTime[Q][1].decode256Time * D256); + DTime1 += DTime1 >> 3; /* advantage to algorithm using less memory, for cache eviction */ + + return DTime1 < DTime0; +} + +typedef size_t (*decompressionAlgo)(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize); + +size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if (cSrcSize > dstSize) + return ERROR(corruption_detected); /* invalid */ + if (cSrcSize == dstSize) { + memcpy(dst, cSrc, dstSize); + return dstSize; + } /* not compressed */ + if (cSrcSize == 1) { + memset(dst, *(const BYTE *)cSrc, dstSize); + return dstSize; + } /* RLE */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} + +size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if ((cSrcSize >= dstSize) || (cSrcSize <= 1)) + return ERROR(corruption_detected); /* invalid */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} + +size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if (cSrcSize > dstSize) + return ERROR(corruption_detected); /* invalid */ + if (cSrcSize == dstSize) { + memcpy(dst, cSrc, dstSize); + return dstSize; + } /* not compressed */ + if (cSrcSize == 1) { + memset(dst, *(const BYTE *)cSrc, dstSize); + return dstSize; + } /* RLE */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress1X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} diff --git a/lib/zstd/mem.h b/lib/zstd/mem.h new file mode 100644 index 000000000000..3a0f34c8706c --- /dev/null +++ b/lib/zstd/mem.h @@ -0,0 +1,151 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +#ifndef MEM_H_MODULE +#define MEM_H_MODULE + +/*-**************************************** +* Dependencies +******************************************/ +#include <asm/unaligned.h> +#include <linux/string.h> /* memcpy */ +#include <linux/types.h> /* size_t, ptrdiff_t */ + +/*-**************************************** +* Compiler specifics +******************************************/ +#define ZSTD_STATIC static __inline __attribute__((unused)) + +/*-************************************************************** +* Basic Types +*****************************************************************/ +typedef uint8_t BYTE; +typedef uint16_t U16; +typedef int16_t S16; +typedef uint32_t U32; +typedef int32_t S32; +typedef uint64_t U64; +typedef int64_t S64; +typedef ptrdiff_t iPtrDiff; +typedef uintptr_t uPtrDiff; + +/*-************************************************************** +* Memory I/O +*****************************************************************/ +ZSTD_STATIC unsigned ZSTD_32bits(void) { return sizeof(size_t) == 4; } +ZSTD_STATIC unsigned ZSTD_64bits(void) { return sizeof(size_t) == 8; } + +#if defined(__LITTLE_ENDIAN) +#define ZSTD_LITTLE_ENDIAN 1 +#else +#define ZSTD_LITTLE_ENDIAN 0 +#endif + +ZSTD_STATIC unsigned ZSTD_isLittleEndian(void) { return ZSTD_LITTLE_ENDIAN; } + +ZSTD_STATIC U16 ZSTD_read16(const void *memPtr) { return get_unaligned((const U16 *)memPtr); } + +ZSTD_STATIC U32 ZSTD_read32(const void *memPtr) { return get_unaligned((const U32 *)memPtr); } + +ZSTD_STATIC U64 ZSTD_read64(const void *memPtr) { return get_unaligned((const U64 *)memPtr); } + +ZSTD_STATIC size_t ZSTD_readST(const void *memPtr) { return get_unaligned((const size_t *)memPtr); } + +ZSTD_STATIC void ZSTD_write16(void *memPtr, U16 value) { put_unaligned(value, (U16 *)memPtr); } + +ZSTD_STATIC void ZSTD_write32(void *memPtr, U32 value) { put_unaligned(value, (U32 *)memPtr); } + +ZSTD_STATIC void ZSTD_write64(void *memPtr, U64 value) { put_unaligned(value, (U64 *)memPtr); } + +/*=== Little endian r/w ===*/ + +ZSTD_STATIC U16 ZSTD_readLE16(const void *memPtr) { return get_unaligned_le16(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE16(void *memPtr, U16 val) { put_unaligned_le16(val, memPtr); } + +ZSTD_STATIC U32 ZSTD_readLE24(const void *memPtr) { return ZSTD_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16); } + +ZSTD_STATIC void ZSTD_writeLE24(void *memPtr, U32 val) +{ + ZSTD_writeLE16(memPtr, (U16)val); + ((BYTE *)memPtr)[2] = (BYTE)(val >> 16); +} + +ZSTD_STATIC U32 ZSTD_readLE32(const void *memPtr) { return get_unaligned_le32(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE32(void *memPtr, U32 val32) { put_unaligned_le32(val32, memPtr); } + +ZSTD_STATIC U64 ZSTD_readLE64(const void *memPtr) { return get_unaligned_le64(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE64(void *memPtr, U64 val64) { put_unaligned_le64(val64, memPtr); } + +ZSTD_STATIC size_t ZSTD_readLEST(const void *memPtr) +{ + if (ZSTD_32bits()) + return (size_t)ZSTD_readLE32(memPtr); + else + return (size_t)ZSTD_readLE64(memPtr); +} + +ZSTD_STATIC void ZSTD_writeLEST(void *memPtr, size_t val) +{ + if (ZSTD_32bits()) + ZSTD_writeLE32(memPtr, (U32)val); + else + ZSTD_writeLE64(memPtr, (U64)val); +} + +/*=== Big endian r/w ===*/ + +ZSTD_STATIC U32 ZSTD_readBE32(const void *memPtr) { return get_unaligned_be32(memPtr); } + +ZSTD_STATIC void ZSTD_writeBE32(void *memPtr, U32 val32) { put_unaligned_be32(val32, memPtr); } + +ZSTD_STATIC U64 ZSTD_readBE64(const void *memPtr) { return get_unaligned_be64(memPtr); } + +ZSTD_STATIC void ZSTD_writeBE64(void *memPtr, U64 val64) { put_unaligned_be64(val64, memPtr); } + +ZSTD_STATIC size_t ZSTD_readBEST(const void *memPtr) +{ + if (ZSTD_32bits()) + return (size_t)ZSTD_readBE32(memPtr); + else + return (size_t)ZSTD_readBE64(memPtr); +} + +ZSTD_STATIC void ZSTD_writeBEST(void *memPtr, size_t val) +{ + if (ZSTD_32bits()) + ZSTD_writeBE32(memPtr, (U32)val); + else + ZSTD_writeBE64(memPtr, (U64)val); +} + +/* function safe only for comparisons */ +ZSTD_STATIC U32 ZSTD_readMINMATCH(const void *memPtr, U32 length) +{ + switch (length) { + default: + case 4: return ZSTD_read32(memPtr); + case 3: + if (ZSTD_isLittleEndian()) + return ZSTD_read32(memPtr) << 8; + else + return ZSTD_read32(memPtr) >> 8; + } +} + +#endif /* MEM_H_MODULE */ diff --git a/lib/zstd/zstd_common.c b/lib/zstd/zstd_common.c new file mode 100644 index 000000000000..a282624ee155 --- /dev/null +++ b/lib/zstd/zstd_common.c @@ -0,0 +1,75 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/*-************************************* +* Dependencies +***************************************/ +#include "error_private.h" +#include "zstd_internal.h" /* declaration of ZSTD_isError, ZSTD_getErrorName, ZSTD_getErrorCode, ZSTD_getErrorString, ZSTD_versionNumber */ +#include <linux/kernel.h> + +/*=************************************************************** +* Custom allocator +****************************************************************/ + +#define stack_push(stack, size) \ + ({ \ + void *const ptr = ZSTD_PTR_ALIGN((stack)->ptr); \ + (stack)->ptr = (char *)ptr + (size); \ + (stack)->ptr <= (stack)->end ? ptr : NULL; \ + }) + +ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize) +{ + ZSTD_customMem stackMem = {ZSTD_stackAlloc, ZSTD_stackFree, workspace}; + ZSTD_stack *stack = (ZSTD_stack *)workspace; + /* Verify preconditions */ + if (!workspace || workspaceSize < sizeof(ZSTD_stack) || workspace != ZSTD_PTR_ALIGN(workspace)) { + ZSTD_customMem error = {NULL, NULL, NULL}; + return error; + } + /* Initialize the stack */ + stack->ptr = workspace; + stack->end = (char *)workspace + workspaceSize; + stack_push(stack, sizeof(ZSTD_stack)); + return stackMem; +} + +void *ZSTD_stackAllocAll(void *opaque, size_t *size) +{ + ZSTD_stack *stack = (ZSTD_stack *)opaque; + *size = (BYTE const *)stack->end - (BYTE *)ZSTD_PTR_ALIGN(stack->ptr); + return stack_push(stack, *size); +} + +void *ZSTD_stackAlloc(void *opaque, size_t size) +{ + ZSTD_stack *stack = (ZSTD_stack *)opaque; + return stack_push(stack, size); +} +void ZSTD_stackFree(void *opaque, void *address) +{ + (void)opaque; + (void)address; +} + +void *ZSTD_malloc(size_t size, ZSTD_customMem customMem) { return customMem.customAlloc(customMem.opaque, size); } + +void ZSTD_free(void *ptr, ZSTD_customMem customMem) +{ + if (ptr != NULL) + customMem.customFree(customMem.opaque, ptr); +} diff --git a/lib/zstd/zstd_internal.h b/lib/zstd/zstd_internal.h new file mode 100644 index 000000000000..1a79fab9e13a --- /dev/null +++ b/lib/zstd/zstd_internal.h @@ -0,0 +1,263 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +#ifndef ZSTD_CCOMMON_H_MODULE +#define ZSTD_CCOMMON_H_MODULE + +/*-******************************************************* +* Compiler specifics +*********************************************************/ +#define FORCE_INLINE static __always_inline +#define FORCE_NOINLINE static noinline + +/*-************************************* +* Dependencies +***************************************/ +#include "error_private.h" +#include "mem.h" +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/xxhash.h> +#include <linux/zstd.h> + +/*-************************************* +* shared macros +***************************************/ +#define MIN(a, b) ((a) < (b) ? (a) : (b)) +#define MAX(a, b) ((a) > (b) ? (a) : (b)) +#define CHECK_F(f) \ + { \ + size_t const errcod = f; \ + if (ERR_isError(errcod)) \ + return errcod; \ + } /* check and Forward error code */ +#define CHECK_E(f, e) \ + { \ + size_t const errcod = f; \ + if (ERR_isError(errcod)) \ + return ERROR(e); \ + } /* check and send Error code */ +#define ZSTD_STATIC_ASSERT(c) \ + { \ + enum { ZSTD_static_assert = 1 / (int)(!!(c)) }; \ + } + +/*-************************************* +* Common constants +***************************************/ +#define ZSTD_OPT_NUM (1 << 12) +#define ZSTD_DICT_MAGIC 0xEC30A437 /* v0.7+ */ + +#define ZSTD_REP_NUM 3 /* number of repcodes */ +#define ZSTD_REP_CHECK (ZSTD_REP_NUM) /* number of repcodes to check by the optimal parser */ +#define ZSTD_REP_MOVE (ZSTD_REP_NUM - 1) +#define ZSTD_REP_MOVE_OPT (ZSTD_REP_NUM) +static const U32 repStartValue[ZSTD_REP_NUM] = {1, 4, 8}; + +#define KB *(1 << 10) +#define MB *(1 << 20) +#define GB *(1U << 30) + +#define BIT7 128 +#define BIT6 64 +#define BIT5 32 +#define BIT4 16 +#define BIT1 2 +#define BIT0 1 + +#define ZSTD_WINDOWLOG_ABSOLUTEMIN 10 +static const size_t ZSTD_fcs_fieldSize[4] = {0, 2, 4, 8}; +static const size_t ZSTD_did_fieldSize[4] = {0, 1, 2, 4}; + +#define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */ +static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE; +typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e; + +#define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */ +#define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */) /* for a non-null block */ + +#define HufLog 12 +typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e; + +#define LONGNBSEQ 0x7F00 + +#define MINMATCH 3 +#define EQUAL_READ32 4 + +#define Litbits 8 +#define MaxLit ((1 << Litbits) - 1) +#define MaxML 52 +#define MaxLL 35 +#define MaxOff 28 +#define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */ +#define MLFSELog 9 +#define LLFSELog 9 +#define OffFSELog 8 + +static const U32 LL_bits[MaxLL + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}; +static const S16 LL_defaultNorm[MaxLL + 1] = {4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1, -1, -1, -1, -1}; +#define LL_DEFAULTNORMLOG 6 /* for static allocation */ +static const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG; + +static const U32 ML_bits[MaxML + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}; +static const S16 ML_defaultNorm[MaxML + 1] = {1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1}; +#define ML_DEFAULTNORMLOG 6 /* for static allocation */ +static const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG; + +static const S16 OF_defaultNorm[MaxOff + 1] = {1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1}; +#define OF_DEFAULTNORMLOG 5 /* for static allocation */ +static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG; + +/*-******************************************* +* Shared functions to include for inlining +*********************************************/ +ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) { + memcpy(dst, src, 8); +} +/*! ZSTD_wildcopy() : +* custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */ +#define WILDCOPY_OVERLENGTH 8 +ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length) +{ + const BYTE* ip = (const BYTE*)src; + BYTE* op = (BYTE*)dst; + BYTE* const oend = op + length; + /* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388. + * Avoid the bad case where the loop only runs once by handling the + * special case separately. This doesn't trigger the bug because it + * doesn't involve pointer/integer overflow. + */ + if (length <= 8) + return ZSTD_copy8(dst, src); + do { + ZSTD_copy8(op, ip); + op += 8; + ip += 8; + } while (op < oend); +} + +/*-******************************************* +* Private interfaces +*********************************************/ +typedef struct ZSTD_stats_s ZSTD_stats_t; + +typedef struct { + U32 off; + U32 len; +} ZSTD_match_t; + +typedef struct { + U32 price; + U32 off; + U32 mlen; + U32 litlen; + U32 rep[ZSTD_REP_NUM]; +} ZSTD_optimal_t; + +typedef struct seqDef_s { + U32 offset; + U16 litLength; + U16 matchLength; +} seqDef; + +typedef struct { + seqDef *sequencesStart; + seqDef *sequences; + BYTE *litStart; + BYTE *lit; + BYTE *llCode; + BYTE *mlCode; + BYTE *ofCode; + U32 longLengthID; /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */ + U32 longLengthPos; + /* opt */ + ZSTD_optimal_t *priceTable; + ZSTD_match_t *matchTable; + U32 *matchLengthFreq; + U32 *litLengthFreq; + U32 *litFreq; + U32 *offCodeFreq; + U32 matchLengthSum; + U32 matchSum; + U32 litLengthSum; + U32 litSum; + U32 offCodeSum; + U32 log2matchLengthSum; + U32 log2matchSum; + U32 log2litLengthSum; + U32 log2litSum; + U32 log2offCodeSum; + U32 factor; + U32 staticPrices; + U32 cachedPrice; + U32 cachedLitLength; + const BYTE *cachedLiterals; +} seqStore_t; + +const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx); +void ZSTD_seqToCodes(const seqStore_t *seqStorePtr); +int ZSTD_isSkipFrame(ZSTD_DCtx *dctx); + +/*= Custom memory allocation functions */ +typedef void *(*ZSTD_allocFunction)(void *opaque, size_t size); +typedef void (*ZSTD_freeFunction)(void *opaque, void *address); +typedef struct { + ZSTD_allocFunction customAlloc; + ZSTD_freeFunction customFree; + void *opaque; +} ZSTD_customMem; + +void *ZSTD_malloc(size_t size, ZSTD_customMem customMem); +void ZSTD_free(void *ptr, ZSTD_customMem customMem); + +/*====== stack allocation ======*/ + +typedef struct { + void *ptr; + const void *end; +} ZSTD_stack; + +#define ZSTD_ALIGN(x) ALIGN(x, sizeof(size_t)) +#define ZSTD_PTR_ALIGN(p) PTR_ALIGN(p, sizeof(size_t)) + +ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize); + +void *ZSTD_stackAllocAll(void *opaque, size_t *size); +void *ZSTD_stackAlloc(void *opaque, size_t size); +void ZSTD_stackFree(void *opaque, void *address); + +/*====== common function ======*/ + +ZSTD_STATIC U32 ZSTD_highbit32(U32 val) { return 31 - __builtin_clz(val); } + +/* hidden functions */ + +/* ZSTD_invalidateRepCodes() : + * ensures next compression will not use repcodes from previous block. + * Note : only works with regular variant; + * do not use with extDict variant ! */ +void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx); + +size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx); +size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx); +size_t ZSTD_freeCDict(ZSTD_CDict *cdict); +size_t ZSTD_freeDDict(ZSTD_DDict *cdict); +size_t ZSTD_freeCStream(ZSTD_CStream *zcs); +size_t ZSTD_freeDStream(ZSTD_DStream *zds); + +#endif /* ZSTD_CCOMMON_H_MODULE */ diff --git a/lib/zstd/zstd_opt.h b/lib/zstd/zstd_opt.h new file mode 100644 index 000000000000..55e1b4cba808 --- /dev/null +++ b/lib/zstd/zstd_opt.h @@ -0,0 +1,1014 @@ +/** + * Copyright (c) 2016-present, Przemyslaw Skibinski, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/* Note : this file is intended to be included within zstd_compress.c */ + +#ifndef ZSTD_OPT_H_91842398743 +#define ZSTD_OPT_H_91842398743 + +#define ZSTD_LITFREQ_ADD 2 +#define ZSTD_FREQ_DIV 4 +#define ZSTD_MAX_PRICE (1 << 30) + +/*-************************************* +* Price functions for optimal parser +***************************************/ +FORCE_INLINE void ZSTD_setLog2Prices(seqStore_t *ssPtr) +{ + ssPtr->log2matchLengthSum = ZSTD_highbit32(ssPtr->matchLengthSum + 1); + ssPtr->log2litLengthSum = ZSTD_highbit32(ssPtr->litLengthSum + 1); + ssPtr->log2litSum = ZSTD_highbit32(ssPtr->litSum + 1); + ssPtr->log2offCodeSum = ZSTD_highbit32(ssPtr->offCodeSum + 1); + ssPtr->factor = 1 + ((ssPtr->litSum >> 5) / ssPtr->litLengthSum) + ((ssPtr->litSum << 1) / (ssPtr->litSum + ssPtr->matchSum)); +} + +ZSTD_STATIC void ZSTD_rescaleFreqs(seqStore_t *ssPtr, const BYTE *src, size_t srcSize) +{ + unsigned u; + + ssPtr->cachedLiterals = NULL; + ssPtr->cachedPrice = ssPtr->cachedLitLength = 0; + ssPtr->staticPrices = 0; + + if (ssPtr->litLengthSum == 0) { + if (srcSize <= 1024) + ssPtr->staticPrices = 1; + + for (u = 0; u <= MaxLit; u++) + ssPtr->litFreq[u] = 0; + for (u = 0; u < srcSize; u++) + ssPtr->litFreq[src[u]]++; + + ssPtr->litSum = 0; + ssPtr->litLengthSum = MaxLL + 1; + ssPtr->matchLengthSum = MaxML + 1; + ssPtr->offCodeSum = (MaxOff + 1); + ssPtr->matchSum = (ZSTD_LITFREQ_ADD << Litbits); + + for (u = 0; u <= MaxLit; u++) { + ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> ZSTD_FREQ_DIV); + ssPtr->litSum += ssPtr->litFreq[u]; + } + for (u = 0; u <= MaxLL; u++) + ssPtr->litLengthFreq[u] = 1; + for (u = 0; u <= MaxML; u++) + ssPtr->matchLengthFreq[u] = 1; + for (u = 0; u <= MaxOff; u++) + ssPtr->offCodeFreq[u] = 1; + } else { + ssPtr->matchLengthSum = 0; + ssPtr->litLengthSum = 0; + ssPtr->offCodeSum = 0; + ssPtr->matchSum = 0; + ssPtr->litSum = 0; + + for (u = 0; u <= MaxLit; u++) { + ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> (ZSTD_FREQ_DIV + 1)); + ssPtr->litSum += ssPtr->litFreq[u]; + } + for (u = 0; u <= MaxLL; u++) { + ssPtr->litLengthFreq[u] = 1 + (ssPtr->litLengthFreq[u] >> (ZSTD_FREQ_DIV + 1)); + ssPtr->litLengthSum += ssPtr->litLengthFreq[u]; + } + for (u = 0; u <= MaxML; u++) { + ssPtr->matchLengthFreq[u] = 1 + (ssPtr->matchLengthFreq[u] >> ZSTD_FREQ_DIV); + ssPtr->matchLengthSum += ssPtr->matchLengthFreq[u]; + ssPtr->matchSum += ssPtr->matchLengthFreq[u] * (u + 3); + } + ssPtr->matchSum *= ZSTD_LITFREQ_ADD; + for (u = 0; u <= MaxOff; u++) { + ssPtr->offCodeFreq[u] = 1 + (ssPtr->offCodeFreq[u] >> ZSTD_FREQ_DIV); + ssPtr->offCodeSum += ssPtr->offCodeFreq[u]; + } + } + + ZSTD_setLog2Prices(ssPtr); +} + +FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t *ssPtr, U32 litLength, const BYTE *literals) +{ + U32 price, u; + + if (ssPtr->staticPrices) + return ZSTD_highbit32((U32)litLength + 1) + (litLength * 6); + + if (litLength == 0) + return ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[0] + 1); + + /* literals */ + if (ssPtr->cachedLiterals == literals) { + U32 const additional = litLength - ssPtr->cachedLitLength; + const BYTE *literals2 = ssPtr->cachedLiterals + ssPtr->cachedLitLength; + price = ssPtr->cachedPrice + additional * ssPtr->log2litSum; + for (u = 0; u < additional; u++) + price -= ZSTD_highbit32(ssPtr->litFreq[literals2[u]] + 1); + ssPtr->cachedPrice = price; + ssPtr->cachedLitLength = litLength; + } else { + price = litLength * ssPtr->log2litSum; + for (u = 0; u < litLength; u++) + price -= ZSTD_highbit32(ssPtr->litFreq[literals[u]] + 1); + + if (litLength >= 12) { + ssPtr->cachedLiterals = literals; + ssPtr->cachedPrice = price; + ssPtr->cachedLitLength = litLength; + } + } + + /* literal Length */ + { + const BYTE LL_deltaCode = 19; + const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength]; + price += LL_bits[llCode] + ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[llCode] + 1); + } + + return price; +} + +FORCE_INLINE U32 ZSTD_getPrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength, const int ultra) +{ + /* offset */ + U32 price; + BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1); + + if (seqStorePtr->staticPrices) + return ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit32((U32)matchLength + 1) + 16 + offCode; + + price = offCode + seqStorePtr->log2offCodeSum - ZSTD_highbit32(seqStorePtr->offCodeFreq[offCode] + 1); + if (!ultra && offCode >= 20) + price += (offCode - 19) * 2; + + /* match Length */ + { + const BYTE ML_deltaCode = 36; + const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength]; + price += ML_bits[mlCode] + seqStorePtr->log2matchLengthSum - ZSTD_highbit32(seqStorePtr->matchLengthFreq[mlCode] + 1); + } + + return price + ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + seqStorePtr->factor; +} + +ZSTD_STATIC void ZSTD_updatePrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength) +{ + U32 u; + + /* literals */ + seqStorePtr->litSum += litLength * ZSTD_LITFREQ_ADD; + for (u = 0; u < litLength; u++) + seqStorePtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD; + + /* literal Length */ + { + const BYTE LL_deltaCode = 19; + const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength]; + seqStorePtr->litLengthFreq[llCode]++; + seqStorePtr->litLengthSum++; + } + + /* match offset */ + { + BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1); + seqStorePtr->offCodeSum++; + seqStorePtr->offCodeFreq[offCode]++; + } + + /* match Length */ + { + const BYTE ML_deltaCode = 36; + const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength]; + seqStorePtr->matchLengthFreq[mlCode]++; + seqStorePtr->matchLengthSum++; + } + + ZSTD_setLog2Prices(seqStorePtr); +} + +#define SET_PRICE(pos, mlen_, offset_, litlen_, price_) \ + { \ + while (last_pos < pos) { \ + opt[last_pos + 1].price = ZSTD_MAX_PRICE; \ + last_pos++; \ + } \ + opt[pos].mlen = mlen_; \ + opt[pos].off = offset_; \ + opt[pos].litlen = litlen_; \ + opt[pos].price = price_; \ + } + +/* Update hashTable3 up to ip (excluded) + Assumption : always within prefix (i.e. not within extDict) */ +FORCE_INLINE +U32 ZSTD_insertAndFindFirstIndexHash3(ZSTD_CCtx *zc, const BYTE *ip) +{ + U32 *const hashTable3 = zc->hashTable3; + U32 const hashLog3 = zc->hashLog3; + const BYTE *const base = zc->base; + U32 idx = zc->nextToUpdate3; + const U32 target = zc->nextToUpdate3 = (U32)(ip - base); + const size_t hash3 = ZSTD_hash3Ptr(ip, hashLog3); + + while (idx < target) { + hashTable3[ZSTD_hash3Ptr(base + idx, hashLog3)] = idx; + idx++; + } + + return hashTable3[hash3]; +} + +/*-************************************* +* Binary Tree search +***************************************/ +static U32 ZSTD_insertBtAndGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, U32 nbCompares, const U32 mls, U32 extDict, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + const BYTE *const base = zc->base; + const U32 curr = (U32)(ip - base); + const U32 hashLog = zc->params.cParams.hashLog; + const size_t h = ZSTD_hashPtr(ip, hashLog, mls); + U32 *const hashTable = zc->hashTable; + U32 matchIndex = hashTable[h]; + U32 *const bt = zc->chainTable; + const U32 btLog = zc->params.cParams.chainLog - 1; + const U32 btMask = (1U << btLog) - 1; + size_t commonLengthSmaller = 0, commonLengthLarger = 0; + const BYTE *const dictBase = zc->dictBase; + const U32 dictLimit = zc->dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const U32 btLow = btMask >= curr ? 0 : curr - btMask; + const U32 windowLow = zc->lowLimit; + U32 *smallerPtr = bt + 2 * (curr & btMask); + U32 *largerPtr = bt + 2 * (curr & btMask) + 1; + U32 matchEndIdx = curr + 8; + U32 dummy32; /* to be nullified at the end */ + U32 mnum = 0; + + const U32 minMatch = (mls == 3) ? 3 : 4; + size_t bestLength = minMatchLen - 1; + + if (minMatch == 3) { /* HC3 match finder */ + U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3(zc, ip); + if (matchIndex3 > windowLow && (curr - matchIndex3 < (1 << 18))) { + const BYTE *match; + size_t currMl = 0; + if ((!extDict) || matchIndex3 >= dictLimit) { + match = base + matchIndex3; + if (match[bestLength] == ip[bestLength]) + currMl = ZSTD_count(ip, match, iLimit); + } else { + match = dictBase + matchIndex3; + if (ZSTD_readMINMATCH(match, MINMATCH) == + ZSTD_readMINMATCH(ip, MINMATCH)) /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */ + currMl = ZSTD_count_2segments(ip + MINMATCH, match + MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH; + } + + /* save best solution */ + if (currMl > bestLength) { + bestLength = currMl; + matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex3; + matches[mnum].len = (U32)currMl; + mnum++; + if (currMl > ZSTD_OPT_NUM) + goto update; + if (ip + currMl == iLimit) + goto update; /* best possible, and avoid read overflow*/ + } + } + } + + hashTable[h] = curr; /* Update Hash Table */ + + while (nbCompares-- && (matchIndex > windowLow)) { + U32 *nextPtr = bt + 2 * (matchIndex & btMask); + size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ + const BYTE *match; + + if ((!extDict) || (matchIndex + matchLength >= dictLimit)) { + match = base + matchIndex; + if (match[matchLength] == ip[matchLength]) { + matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iLimit) + 1; + } + } else { + match = dictBase + matchIndex; + matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iLimit, dictEnd, prefixStart); + if (matchIndex + matchLength >= dictLimit) + match = base + matchIndex; /* to prepare for next usage of match[matchLength] */ + } + + if (matchLength > bestLength) { + if (matchLength > matchEndIdx - matchIndex) + matchEndIdx = matchIndex + (U32)matchLength; + bestLength = matchLength; + matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex; + matches[mnum].len = (U32)matchLength; + mnum++; + if (matchLength > ZSTD_OPT_NUM) + break; + if (ip + matchLength == iLimit) /* equal : no way to know if inf or sup */ + break; /* drop, to guarantee consistency (miss a little bit of compression) */ + } + + if (match[matchLength] < ip[matchLength]) { + /* match is smaller than curr */ + *smallerPtr = matchIndex; /* update smaller idx */ + commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */ + if (matchIndex <= btLow) { + smallerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */ + matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */ + } else { + /* match is larger than curr */ + *largerPtr = matchIndex; + commonLengthLarger = matchLength; + if (matchIndex <= btLow) { + largerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + largerPtr = nextPtr; + matchIndex = nextPtr[0]; + } + } + + *smallerPtr = *largerPtr = 0; + +update: + zc->nextToUpdate = (matchEndIdx > curr + 8) ? matchEndIdx - 8 : curr + 1; + return mnum; +} + +/** Tree updater, providing best match */ +static U32 ZSTD_BtGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls, ZSTD_match_t *matches, + const U32 minMatchLen) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 0, matches, minMatchLen); +} + +static U32 ZSTD_BtGetAllMatches_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + switch (matchLengthSearch) { + case 3: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen); + default: + case 4: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen); + case 5: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen); + case 7: + case 6: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen); + } +} + +/** Tree updater, providing best match */ +static U32 ZSTD_BtGetAllMatches_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 1, matches, minMatchLen); +} + +static U32 ZSTD_BtGetAllMatches_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + switch (matchLengthSearch) { + case 3: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen); + default: + case 4: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen); + case 5: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen); + case 7: + case 6: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen); + } +} + +/*-******************************* +* Optimal parser +*********************************/ +FORCE_INLINE +void ZSTD_compressBlock_opt_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base; + const BYTE *const prefixStart = base + ctx->dictLimit; + + const U32 maxSearches = 1U << ctx->params.cParams.searchLog; + const U32 sufficient_len = ctx->params.cParams.targetLength; + const U32 mls = ctx->params.cParams.searchLength; + const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4; + + ZSTD_optimal_t *opt = seqStorePtr->priceTable; + ZSTD_match_t *matches = seqStorePtr->matchTable; + const BYTE *inr; + U32 offset, rep[ZSTD_REP_NUM]; + + /* init */ + ctx->nextToUpdate3 = ctx->nextToUpdate; + ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize); + ip += (ip == prefixStart); + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + rep[i] = ctx->rep[i]; + } + + /* Match Loop */ + while (ip < ilimit) { + U32 cur, match_num, last_pos, litlen, price; + U32 u, mlen, best_mlen, best_off, litLength; + memset(opt, 0, sizeof(ZSTD_optimal_t)); + last_pos = 0; + litlen = (U32)(ip - anchor); + + /* check repCode */ + { + U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor); + for (i = (ip == anchor); i < last_i; i++) { + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i]; + if ((repCur > 0) && (repCur < (S32)(ip - prefixStart)) && + (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repCur, minMatch))) { + mlen = (U32)ZSTD_count(ip + minMatch, ip + minMatch - repCur, iend) + minMatch; + if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + best_off = i - (ip == anchor); + do { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */ + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, ip, iend, maxSearches, mls, matches, minMatch); + + if (!last_pos && !match_num) { + ip++; + continue; + } + + if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + + /* set prices using matches at position = 0 */ + best_mlen = (last_pos) ? last_pos : minMatch; + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + while (mlen <= best_mlen) { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, matches[u].off, litlen, price); /* note : macro modifies last_pos */ + mlen++; + } + } + + if (last_pos < minMatch) { + ip++; + continue; + } + + /* initialize opt[0] */ + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + opt[0].rep[i] = rep[i]; + } + opt[0].mlen = 1; + opt[0].litlen = litlen; + + /* check further positions */ + for (cur = 1; cur <= last_pos; cur++) { + inr = ip + cur; + + if (opt[cur - 1].mlen == 1) { + litlen = opt[cur - 1].litlen + 1; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen); + } else + price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor); + } else { + litlen = 1; + price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1); + } + + if (cur > last_pos || price <= opt[cur].price) + SET_PRICE(cur, 1, 0, litlen, price); + + if (cur == last_pos) + break; + + if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */ + continue; + + mlen = opt[cur].mlen; + if (opt[cur].off > ZSTD_REP_MOVE_OPT) { + opt[cur].rep[2] = opt[cur - mlen].rep[1]; + opt[cur].rep[1] = opt[cur - mlen].rep[0]; + opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT; + } else { + opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2]; + opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1]; + opt[cur].rep[0] = + ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]); + } + + best_mlen = minMatch; + { + U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1); + for (i = (opt[cur].mlen != 1); i < last_i; i++) { /* check rep */ + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i]; + if ((repCur > 0) && (repCur < (S32)(inr - prefixStart)) && + (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(inr - repCur, minMatch))) { + mlen = (U32)ZSTD_count(inr + minMatch, inr + minMatch - repCur, iend) + minMatch; + + if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + last_pos = cur + 1; + goto _storeSequence; + } + + best_off = i - (opt[cur].mlen != 1); + if (mlen > best_mlen) + best_mlen = mlen; + + do { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen, + best_off, mlen - MINMATCH, ultra); + } else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || price <= opt[cur + mlen].price) + SET_PRICE(cur + mlen, mlen, i, litlen, price); + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, inr, iend, maxSearches, mls, matches, best_mlen); + + if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + last_pos = cur + 1; + goto _storeSequence; + } + + /* set prices using matches at position = cur */ + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + + while (mlen <= best_mlen) { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen, + matches[u].off - 1, mlen - MINMATCH, ultra); + else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || (price < opt[cur + mlen].price)) + SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price); + + mlen++; + } + } + } + + best_mlen = opt[last_pos].mlen; + best_off = opt[last_pos].off; + cur = last_pos - best_mlen; + + /* store sequence */ +_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */ + opt[0].mlen = 1; + + while (1) { + mlen = opt[cur].mlen; + offset = opt[cur].off; + opt[cur].mlen = best_mlen; + opt[cur].off = best_off; + best_mlen = mlen; + best_off = offset; + if (mlen > cur) + break; + cur -= mlen; + } + + for (u = 0; u <= last_pos;) { + u += opt[u].mlen; + } + + for (cur = 0; cur < last_pos;) { + mlen = opt[cur].mlen; + if (mlen == 1) { + ip++; + cur++; + continue; + } + offset = opt[cur].off; + cur += mlen; + litLength = (U32)(ip - anchor); + + if (offset > ZSTD_REP_MOVE_OPT) { + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = offset - ZSTD_REP_MOVE_OPT; + offset--; + } else { + if (offset != 0) { + best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]); + if (offset != 1) + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = best_off; + } + if (litLength == 0) + offset--; + } + + ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + anchor = ip = ip + mlen; + } + } /* for (cur=0; cur < last_pos; ) */ + + /* Save reps for next block */ + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + ctx->repToConfirm[i] = rep[i]; + } + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +FORCE_INLINE +void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base; + const U32 lowestIndex = ctx->lowLimit; + const U32 dictLimit = ctx->dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const BYTE *const dictBase = ctx->dictBase; + const BYTE *const dictEnd = dictBase + dictLimit; + + const U32 maxSearches = 1U << ctx->params.cParams.searchLog; + const U32 sufficient_len = ctx->params.cParams.targetLength; + const U32 mls = ctx->params.cParams.searchLength; + const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4; + + ZSTD_optimal_t *opt = seqStorePtr->priceTable; + ZSTD_match_t *matches = seqStorePtr->matchTable; + const BYTE *inr; + + /* init */ + U32 offset, rep[ZSTD_REP_NUM]; + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + rep[i] = ctx->rep[i]; + } + + ctx->nextToUpdate3 = ctx->nextToUpdate; + ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize); + ip += (ip == prefixStart); + + /* Match Loop */ + while (ip < ilimit) { + U32 cur, match_num, last_pos, litlen, price; + U32 u, mlen, best_mlen, best_off, litLength; + U32 curr = (U32)(ip - base); + memset(opt, 0, sizeof(ZSTD_optimal_t)); + last_pos = 0; + opt[0].litlen = (U32)(ip - anchor); + + /* check repCode */ + { + U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor); + for (i = (ip == anchor); i < last_i; i++) { + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i]; + const U32 repIndex = (U32)(curr - repCur); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if ((repCur > 0 && repCur <= (S32)curr) && + (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) { + /* repcode detected we should take it */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + mlen = (U32)ZSTD_count_2segments(ip + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch; + + if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + + best_off = i - (ip == anchor); + litlen = opt[0].litlen; + do { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */ + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, ip, iend, maxSearches, mls, matches, minMatch); /* first search (depth 0) */ + + if (!last_pos && !match_num) { + ip++; + continue; + } + + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + opt[0].rep[i] = rep[i]; + } + opt[0].mlen = 1; + + if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + + best_mlen = (last_pos) ? last_pos : minMatch; + + /* set prices using matches at position = 0 */ + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + litlen = opt[0].litlen; + while (mlen <= best_mlen) { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, matches[u].off, litlen, price); + mlen++; + } + } + + if (last_pos < minMatch) { + ip++; + continue; + } + + /* check further positions */ + for (cur = 1; cur <= last_pos; cur++) { + inr = ip + cur; + + if (opt[cur - 1].mlen == 1) { + litlen = opt[cur - 1].litlen + 1; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen); + } else + price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor); + } else { + litlen = 1; + price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1); + } + + if (cur > last_pos || price <= opt[cur].price) + SET_PRICE(cur, 1, 0, litlen, price); + + if (cur == last_pos) + break; + + if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */ + continue; + + mlen = opt[cur].mlen; + if (opt[cur].off > ZSTD_REP_MOVE_OPT) { + opt[cur].rep[2] = opt[cur - mlen].rep[1]; + opt[cur].rep[1] = opt[cur - mlen].rep[0]; + opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT; + } else { + opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2]; + opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1]; + opt[cur].rep[0] = + ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]); + } + + best_mlen = minMatch; + { + U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1); + for (i = (mlen != 1); i < last_i; i++) { + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i]; + const U32 repIndex = (U32)(curr + cur - repCur); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if ((repCur > 0 && repCur <= (S32)(curr + cur)) && + (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) { + /* repcode detected */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + mlen = (U32)ZSTD_count_2segments(inr + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch; + + if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + last_pos = cur + 1; + goto _storeSequence; + } + + best_off = i - (opt[cur].mlen != 1); + if (mlen > best_mlen) + best_mlen = mlen; + + do { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen, + best_off, mlen - MINMATCH, ultra); + } else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || price <= opt[cur + mlen].price) + SET_PRICE(cur + mlen, mlen, i, litlen, price); + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, inr, iend, maxSearches, mls, matches, minMatch); + + if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + last_pos = cur + 1; + goto _storeSequence; + } + + /* set prices using matches at position = cur */ + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + + while (mlen <= best_mlen) { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen, + matches[u].off - 1, mlen - MINMATCH, ultra); + else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || (price < opt[cur + mlen].price)) + SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price); + + mlen++; + } + } + } /* for (cur = 1; cur <= last_pos; cur++) */ + + best_mlen = opt[last_pos].mlen; + best_off = opt[last_pos].off; + cur = last_pos - best_mlen; + + /* store sequence */ +_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */ + opt[0].mlen = 1; + + while (1) { + mlen = opt[cur].mlen; + offset = opt[cur].off; + opt[cur].mlen = best_mlen; + opt[cur].off = best_off; + best_mlen = mlen; + best_off = offset; + if (mlen > cur) + break; + cur -= mlen; + } + + for (u = 0; u <= last_pos;) { + u += opt[u].mlen; + } + + for (cur = 0; cur < last_pos;) { + mlen = opt[cur].mlen; + if (mlen == 1) { + ip++; + cur++; + continue; + } + offset = opt[cur].off; + cur += mlen; + litLength = (U32)(ip - anchor); + + if (offset > ZSTD_REP_MOVE_OPT) { + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = offset - ZSTD_REP_MOVE_OPT; + offset--; + } else { + if (offset != 0) { + best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]); + if (offset != 1) + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = best_off; + } + + if (litLength == 0) + offset--; + } + + ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + anchor = ip = ip + mlen; + } + } /* for (cur=0; cur < last_pos; ) */ + + /* Save reps for next block */ + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + ctx->repToConfirm[i] = rep[i]; + } + + /* Last Literals */ + { + size_t lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +#endif /* ZSTD_OPT_H_91842398743 */ |