1180 lines
42 KiB
C
1180 lines
42 KiB
C
/*
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zstd - standard compression library
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Copyright (C) 2014-2016, Yann Collet.
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BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are
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met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above
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copyright notice, this list of conditions and the following disclaimer
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in the documentation and/or other materials provided with the
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distribution.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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You can contact the author at :
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- zstd source repository : https://github.com/Cyan4973/zstd
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*/
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/* ***************************************************************
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* Tuning parameters
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*****************************************************************/
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/*!
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* HEAPMODE :
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* Select how default decompression function ZSTD_decompress() will allocate memory,
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* in memory stack (0), or in memory heap (1, requires malloc())
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*/
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#ifndef ZSTD_HEAPMODE
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# define ZSTD_HEAPMODE 1
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#endif
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/*!
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* LEGACY_SUPPORT :
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* if set to 1, ZSTD_decompress() can decode older formats (v0.1+)
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*/
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#ifndef ZSTD_LEGACY_SUPPORT
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# define ZSTD_LEGACY_SUPPORT 0
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#endif
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/*-*******************************************************
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* Dependencies
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*********************************************************/
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#include <stdlib.h> /* calloc */
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#include <string.h> /* memcpy, memmove */
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#include <stdio.h> /* debug only : printf */
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#include "mem.h" /* low level memory routines */
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#include "zstd_internal.h"
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#include "fse_static.h"
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#include "huff0_static.h"
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#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
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# include "zstd_legacy.h"
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#endif
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/*-*******************************************************
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* Compiler specifics
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*********************************************************/
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#ifdef _MSC_VER /* Visual Studio */
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# define FORCE_INLINE static __forceinline
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# include <intrin.h> /* For Visual 2005 */
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# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
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# pragma warning(disable : 4324) /* disable: C4324: padded structure */
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#else
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# define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
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# ifdef __GNUC__
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# define FORCE_INLINE static inline __attribute__((always_inline))
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# else
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# define FORCE_INLINE static inline
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# endif
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#endif
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/*-*************************************
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* Local types
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***************************************/
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typedef struct
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{
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blockType_t blockType;
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U32 origSize;
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} blockProperties_t;
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/* *******************************************************
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* Memory operations
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**********************************************************/
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static void ZSTD_copy4(void* dst, const void* src) { memcpy(dst, src, 4); }
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/* *************************************
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* Error Management
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***************************************/
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unsigned ZSTD_versionNumber (void) { return ZSTD_VERSION_NUMBER; }
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/*! ZSTD_isError() :
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* tells if a return value is an error code */
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unsigned ZSTD_isError(size_t code) { return ERR_isError(code); }
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/*! ZSTD_getError() :
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* convert a `size_t` function result into a proper ZSTD_errorCode enum */
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ZSTD_ErrorCode ZSTD_getError(size_t code) { return ERR_getError(code); }
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/*! ZSTD_getErrorName() :
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* provides error code string (useful for debugging) */
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const char* ZSTD_getErrorName(size_t code) { return ERR_getErrorName(code); }
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/* *************************************************************
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* Context management
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***************************************************************/
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typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader,
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ZSTDds_decodeBlockHeader, ZSTDds_decompressBlock } ZSTD_dStage;
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struct ZSTD_DCtx_s
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{
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FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)];
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FSE_DTable OffTable[FSE_DTABLE_SIZE_U32(OffFSELog)];
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FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)];
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unsigned hufTableX4[HUF_DTABLE_SIZE(HufLog)];
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const void* previousDstEnd;
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const void* base;
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const void* vBase;
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const void* dictEnd;
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size_t expected;
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size_t headerSize;
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ZSTD_parameters params;
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blockType_t bType; /* used in ZSTD_decompressContinue(), to transfer blockType between header decoding and block decoding stages */
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ZSTD_dStage stage;
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U32 flagStaticTables;
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const BYTE* litPtr;
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size_t litBufSize;
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size_t litSize;
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BYTE litBuffer[BLOCKSIZE + WILDCOPY_OVERLENGTH];
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BYTE headerBuffer[ZSTD_frameHeaderSize_max];
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}; /* typedef'd to ZSTD_DCtx within "zstd_static.h" */
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size_t sizeofDCtx (void) { return sizeof(ZSTD_DCtx); }
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size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx)
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{
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dctx->expected = ZSTD_frameHeaderSize_min;
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dctx->stage = ZSTDds_getFrameHeaderSize;
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dctx->previousDstEnd = NULL;
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dctx->base = NULL;
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dctx->vBase = NULL;
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dctx->dictEnd = NULL;
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dctx->hufTableX4[0] = HufLog;
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dctx->flagStaticTables = 0;
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dctx->params.searchLength = MINMATCH; /* overwritten by frame but forces ZSTD_btopt to MINMATCH in block mode */
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ZSTD_LOG_BLOCK("%p: ZSTD_decompressBegin searchLength=%d\n", dctx->base, dctx->params.searchLength);
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return 0;
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}
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ZSTD_DCtx* ZSTD_createDCtx(void)
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{
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ZSTD_DCtx* dctx = (ZSTD_DCtx*)malloc(sizeof(ZSTD_DCtx));
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if (dctx==NULL) return NULL;
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ZSTD_decompressBegin(dctx);
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return dctx;
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}
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size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx)
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{
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free(dctx);
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return 0; /* reserved as a potential error code in the future */
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}
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void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx)
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{
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memcpy(dstDCtx, srcDCtx,
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sizeof(ZSTD_DCtx) - (BLOCKSIZE+WILDCOPY_OVERLENGTH + ZSTD_frameHeaderSize_max)); /* no need to copy workspace */
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}
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/* *************************************************************
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* Decompression section
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***************************************************************/
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/* Frame format description
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Frame Header - [ Block Header - Block ] - Frame End
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1) Frame Header
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- 4 bytes - Magic Number : ZSTD_MAGICNUMBER (defined within zstd_internal.h)
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- 1 byte - Window Descriptor
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2) Block Header
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- 3 bytes, starting with a 2-bits descriptor
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Uncompressed, Compressed, Frame End, unused
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3) Block
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See Block Format Description
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4) Frame End
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- 3 bytes, compatible with Block Header
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*/
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/* Block format description
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Block = Literal Section - Sequences Section
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Prerequisite : size of (compressed) block, maximum size of regenerated data
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1) Literal Section
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1.1) Header : 1-5 bytes
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flags: 2 bits
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00 compressed by Huff0
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01 unused
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10 is Raw (uncompressed)
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11 is Rle
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Note : using 01 => Huff0 with precomputed table ?
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Note : delta map ? => compressed ?
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1.1.1) Huff0-compressed literal block : 3-5 bytes
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srcSize < 1 KB => 3 bytes (2-2-10-10) => single stream
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srcSize < 1 KB => 3 bytes (2-2-10-10)
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srcSize < 16KB => 4 bytes (2-2-14-14)
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else => 5 bytes (2-2-18-18)
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big endian convention
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1.1.2) Raw (uncompressed) literal block header : 1-3 bytes
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size : 5 bits: (IS_RAW<<6) + (0<<4) + size
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12 bits: (IS_RAW<<6) + (2<<4) + (size>>8)
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size&255
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20 bits: (IS_RAW<<6) + (3<<4) + (size>>16)
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size>>8&255
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size&255
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1.1.3) Rle (repeated single byte) literal block header : 1-3 bytes
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size : 5 bits: (IS_RLE<<6) + (0<<4) + size
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12 bits: (IS_RLE<<6) + (2<<4) + (size>>8)
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size&255
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20 bits: (IS_RLE<<6) + (3<<4) + (size>>16)
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size>>8&255
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size&255
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1.1.4) Huff0-compressed literal block, using precomputed CTables : 3-5 bytes
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srcSize < 1 KB => 3 bytes (2-2-10-10) => single stream
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srcSize < 1 KB => 3 bytes (2-2-10-10)
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srcSize < 16KB => 4 bytes (2-2-14-14)
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else => 5 bytes (2-2-18-18)
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big endian convention
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1- CTable available (stored into workspace ?)
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2- Small input (fast heuristic ? Full comparison ? depend on clevel ?)
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1.2) Literal block content
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1.2.1) Huff0 block, using sizes from header
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See Huff0 format
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1.2.2) Huff0 block, using prepared table
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1.2.3) Raw content
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1.2.4) single byte
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2) Sequences section
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TO DO
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*/
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/** ZSTD_decodeFrameHeader_Part1() :
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* decode the 1st part of the Frame Header, which tells Frame Header size.
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* srcSize must be == ZSTD_frameHeaderSize_min.
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* @return : the full size of the Frame Header */
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static size_t ZSTD_decodeFrameHeader_Part1(ZSTD_DCtx* zc, const void* src, size_t srcSize)
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{
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U32 magicNumber;
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if (srcSize != ZSTD_frameHeaderSize_min)
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return ERROR(srcSize_wrong);
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magicNumber = MEM_readLE32(src);
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if (magicNumber != ZSTD_MAGICNUMBER) return ERROR(prefix_unknown);
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zc->headerSize = ZSTD_frameHeaderSize_min;
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return zc->headerSize;
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}
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size_t ZSTD_getFrameParams(ZSTD_parameters* params, const void* src, size_t srcSize)
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{
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U32 magicNumber;
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if (srcSize < ZSTD_frameHeaderSize_min) return ZSTD_frameHeaderSize_max;
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magicNumber = MEM_readLE32(src);
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if (magicNumber != ZSTD_MAGICNUMBER) return ERROR(prefix_unknown);
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memset(params, 0, sizeof(*params));
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params->windowLog = (((const BYTE*)src)[4] & 15) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
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params->searchLength = (((const BYTE*)src)[4] & 16) ? MINMATCH-1 : MINMATCH;
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if ((((const BYTE*)src)[4] >> 5) != 0) return ERROR(frameParameter_unsupported); /* reserved 3 bits */
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return 0;
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}
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/** ZSTD_decodeFrameHeader_Part2() :
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* decode the full Frame Header.
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* srcSize must be the size provided by ZSTD_decodeFrameHeader_Part1().
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* @return : 0, or an error code, which can be tested using ZSTD_isError() */
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static size_t ZSTD_decodeFrameHeader_Part2(ZSTD_DCtx* zc, const void* src, size_t srcSize)
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{
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size_t result;
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if (srcSize != zc->headerSize)
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return ERROR(srcSize_wrong);
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result = ZSTD_getFrameParams(&(zc->params), src, srcSize);
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if ((MEM_32bits()) && (zc->params.windowLog > 25)) return ERROR(frameParameter_unsupportedBy32bits);
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return result;
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}
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size_t ZSTD_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr)
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{
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const BYTE* const in = (const BYTE* const)src;
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BYTE headerFlags;
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U32 cSize;
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if (srcSize < 3)
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return ERROR(srcSize_wrong);
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headerFlags = *in;
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cSize = in[2] + (in[1]<<8) + ((in[0] & 7)<<16);
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bpPtr->blockType = (blockType_t)(headerFlags >> 6);
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bpPtr->origSize = (bpPtr->blockType == bt_rle) ? cSize : 0;
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if (bpPtr->blockType == bt_end) return 0;
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if (bpPtr->blockType == bt_rle) return 1;
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return cSize;
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}
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static size_t ZSTD_copyRawBlock(void* dst, size_t maxDstSize, const void* src, size_t srcSize)
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{
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if (srcSize > maxDstSize) return ERROR(dstSize_tooSmall);
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memcpy(dst, src, srcSize);
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return srcSize;
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}
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/*! ZSTD_decodeLiteralsBlock() :
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@return : nb of bytes read from src (< srcSize ) */
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size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
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const void* src, size_t srcSize) /* note : srcSize < BLOCKSIZE */
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{
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const BYTE* const istart = (const BYTE*) src;
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/* any compressed block with literals segment must be at least this size */
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if (srcSize < MIN_CBLOCK_SIZE) return ERROR(corruption_detected);
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switch(istart[0]>> 6)
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{
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case IS_HUF:
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{
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size_t litSize, litCSize, singleStream=0;
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U32 lhSize = ((istart[0]) >> 4) & 3;
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switch(lhSize)
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{
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case 0: case 1: default: /* note : default is impossible, since lhSize into [0..3] */
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/* 2 - 2 - 10 - 10 */
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lhSize=3;
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singleStream = istart[0] & 16;
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litSize = ((istart[0] & 15) << 6) + (istart[1] >> 2);
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litCSize = ((istart[1] & 3) << 8) + istart[2];
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break;
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case 2:
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/* 2 - 2 - 14 - 14 */
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lhSize=4;
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litSize = ((istart[0] & 15) << 10) + (istart[1] << 2) + (istart[2] >> 6);
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litCSize = ((istart[2] & 63) << 8) + istart[3];
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break;
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case 3:
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/* 2 - 2 - 18 - 18 */
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lhSize=5;
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litSize = ((istart[0] & 15) << 14) + (istart[1] << 6) + (istart[2] >> 2);
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litCSize = ((istart[2] & 3) << 16) + (istart[3] << 8) + istart[4];
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break;
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}
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if (litSize > BLOCKSIZE) return ERROR(corruption_detected);
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if (HUF_isError(singleStream ?
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HUF_decompress1X2(dctx->litBuffer, litSize, istart+lhSize, litCSize) :
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HUF_decompress (dctx->litBuffer, litSize, istart+lhSize, litCSize) ))
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return ERROR(corruption_detected);
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dctx->litPtr = dctx->litBuffer;
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dctx->litBufSize = BLOCKSIZE+8;
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dctx->litSize = litSize;
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return litCSize + lhSize;
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}
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case IS_PCH:
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{
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size_t errorCode;
|
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size_t litSize, litCSize;
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U32 lhSize = ((istart[0]) >> 4) & 3;
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if (lhSize != 1) /* only case supported for now : small litSize, single stream */
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return ERROR(corruption_detected);
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if (!dctx->flagStaticTables)
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return ERROR(dictionary_corrupted);
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/* 2 - 2 - 10 - 10 */
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lhSize=3;
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litSize = ((istart[0] & 15) << 6) + (istart[1] >> 2);
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litCSize = ((istart[1] & 3) << 8) + istart[2];
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errorCode = HUF_decompress1X4_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->hufTableX4);
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if (HUF_isError(errorCode)) return ERROR(corruption_detected);
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dctx->litPtr = dctx->litBuffer;
|
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dctx->litBufSize = BLOCKSIZE+WILDCOPY_OVERLENGTH;
|
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dctx->litSize = litSize;
|
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return litCSize + lhSize;
|
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}
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case IS_RAW:
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{
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size_t litSize;
|
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U32 lhSize = ((istart[0]) >> 4) & 3;
|
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switch(lhSize)
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{
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case 0: case 1: default: /* note : default is impossible, since lhSize into [0..3] */
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lhSize=1;
|
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litSize = istart[0] & 31;
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break;
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case 2:
|
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litSize = ((istart[0] & 15) << 8) + istart[1];
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break;
|
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case 3:
|
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litSize = ((istart[0] & 15) << 16) + (istart[1] << 8) + istart[2];
|
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break;
|
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}
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|
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if (lhSize+litSize+WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */
|
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if (litSize+lhSize > srcSize) return ERROR(corruption_detected);
|
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memcpy(dctx->litBuffer, istart+lhSize, litSize);
|
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dctx->litPtr = dctx->litBuffer;
|
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dctx->litBufSize = BLOCKSIZE+8;
|
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dctx->litSize = litSize;
|
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return lhSize+litSize;
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}
|
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/* direct reference into compressed stream */
|
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dctx->litPtr = istart+lhSize;
|
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dctx->litBufSize = srcSize-lhSize;
|
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dctx->litSize = litSize;
|
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return lhSize+litSize;
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}
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case IS_RLE:
|
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{
|
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size_t litSize;
|
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U32 lhSize = ((istart[0]) >> 4) & 3;
|
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switch(lhSize)
|
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{
|
|
case 0: case 1: default: /* note : default is impossible, since lhSize into [0..3] */
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lhSize = 1;
|
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litSize = istart[0] & 31;
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break;
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case 2:
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litSize = ((istart[0] & 15) << 8) + istart[1];
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break;
|
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case 3:
|
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litSize = ((istart[0] & 15) << 16) + (istart[1] << 8) + istart[2];
|
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break;
|
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}
|
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if (litSize > BLOCKSIZE) return ERROR(corruption_detected);
|
|
memset(dctx->litBuffer, istart[lhSize], litSize);
|
|
dctx->litPtr = dctx->litBuffer;
|
|
dctx->litBufSize = BLOCKSIZE+WILDCOPY_OVERLENGTH;
|
|
dctx->litSize = litSize;
|
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return lhSize+1;
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}
|
|
default:
|
|
return ERROR(corruption_detected); /* impossible */
|
|
}
|
|
}
|
|
|
|
|
|
size_t ZSTD_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr,
|
|
FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
const BYTE* const istart = (const BYTE* const)src;
|
|
const BYTE* ip = istart;
|
|
const BYTE* const iend = istart + srcSize;
|
|
U32 LLtype, Offtype, MLtype;
|
|
U32 LLlog, Offlog, MLlog;
|
|
size_t dumpsLength;
|
|
|
|
/* check */
|
|
if (srcSize < MIN_SEQUENCES_SIZE)
|
|
return ERROR(srcSize_wrong);
|
|
|
|
/* SeqHead */
|
|
*nbSeq = *ip++;
|
|
if (*nbSeq==0) return 1;
|
|
if (*nbSeq >= 0x7F) {
|
|
if (*nbSeq == 0xFF)
|
|
*nbSeq = MEM_readLE16(ip) + LONGNBSEQ, ip+=2;
|
|
else
|
|
*nbSeq = ((nbSeq[0]-0x80)<<8) + *ip++;
|
|
}
|
|
|
|
/* FSE table descriptors */
|
|
LLtype = *ip >> 6;
|
|
Offtype = (*ip >> 4) & 3;
|
|
MLtype = (*ip >> 2) & 3;
|
|
if (*ip & 2) {
|
|
dumpsLength = ip[2];
|
|
dumpsLength += ip[1] << 8;
|
|
ip += 3;
|
|
} else {
|
|
dumpsLength = ip[1];
|
|
dumpsLength += (ip[0] & 1) << 8;
|
|
ip += 2;
|
|
}
|
|
*dumpsPtr = ip;
|
|
ip += dumpsLength;
|
|
*dumpsLengthPtr = dumpsLength;
|
|
|
|
/* check */
|
|
if (ip > iend-3) return ERROR(srcSize_wrong); /* min : all 3 are "raw", hence no header, but at least xxLog bits per type */
|
|
|
|
/* sequences */
|
|
{
|
|
S16 norm[MaxML+1]; /* assumption : MaxML >= MaxLL >= MaxOff */
|
|
size_t headerSize;
|
|
|
|
/* Build DTables */
|
|
switch(LLtype)
|
|
{
|
|
U32 max;
|
|
case FSE_ENCODING_RLE :
|
|
LLlog = 0;
|
|
FSE_buildDTable_rle(DTableLL, *ip++);
|
|
break;
|
|
case FSE_ENCODING_RAW :
|
|
LLlog = LLbits;
|
|
FSE_buildDTable_raw(DTableLL, LLbits);
|
|
break;
|
|
case FSE_ENCODING_STATIC:
|
|
break;
|
|
case FSE_ENCODING_DYNAMIC :
|
|
default : /* impossible */
|
|
max = MaxLL;
|
|
headerSize = FSE_readNCount(norm, &max, &LLlog, ip, iend-ip);
|
|
if (FSE_isError(headerSize)) return ERROR(GENERIC);
|
|
if (LLlog > LLFSELog) return ERROR(corruption_detected);
|
|
ip += headerSize;
|
|
FSE_buildDTable(DTableLL, norm, max, LLlog);
|
|
}
|
|
|
|
switch(Offtype)
|
|
{
|
|
U32 max;
|
|
case FSE_ENCODING_RLE :
|
|
Offlog = 0;
|
|
if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */
|
|
FSE_buildDTable_rle(DTableOffb, *ip++ & MaxOff); /* if *ip > MaxOff, data is corrupted */
|
|
break;
|
|
case FSE_ENCODING_RAW :
|
|
Offlog = Offbits;
|
|
FSE_buildDTable_raw(DTableOffb, Offbits);
|
|
break;
|
|
case FSE_ENCODING_STATIC:
|
|
break;
|
|
case FSE_ENCODING_DYNAMIC :
|
|
default : /* impossible */
|
|
max = MaxOff;
|
|
headerSize = FSE_readNCount(norm, &max, &Offlog, ip, iend-ip);
|
|
if (FSE_isError(headerSize)) return ERROR(GENERIC);
|
|
if (Offlog > OffFSELog) return ERROR(corruption_detected);
|
|
ip += headerSize;
|
|
FSE_buildDTable(DTableOffb, norm, max, Offlog);
|
|
}
|
|
|
|
switch(MLtype)
|
|
{
|
|
U32 max;
|
|
case FSE_ENCODING_RLE :
|
|
MLlog = 0;
|
|
if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */
|
|
FSE_buildDTable_rle(DTableML, *ip++);
|
|
break;
|
|
case FSE_ENCODING_RAW :
|
|
MLlog = MLbits;
|
|
FSE_buildDTable_raw(DTableML, MLbits);
|
|
break;
|
|
case FSE_ENCODING_STATIC:
|
|
break;
|
|
case FSE_ENCODING_DYNAMIC :
|
|
default : /* impossible */
|
|
max = MaxML;
|
|
headerSize = FSE_readNCount(norm, &max, &MLlog, ip, iend-ip);
|
|
if (FSE_isError(headerSize)) return ERROR(GENERIC);
|
|
if (MLlog > MLFSELog) return ERROR(corruption_detected);
|
|
ip += headerSize;
|
|
FSE_buildDTable(DTableML, norm, max, MLlog);
|
|
} }
|
|
|
|
return ip-istart;
|
|
}
|
|
|
|
|
|
typedef struct {
|
|
size_t litLength;
|
|
size_t matchLength;
|
|
size_t offset;
|
|
} seq_t;
|
|
|
|
typedef struct {
|
|
BIT_DStream_t DStream;
|
|
FSE_DState_t stateLL;
|
|
FSE_DState_t stateOffb;
|
|
FSE_DState_t stateML;
|
|
size_t prevOffset;
|
|
const BYTE* dumps;
|
|
const BYTE* dumpsEnd;
|
|
} seqState_t;
|
|
|
|
|
|
|
|
static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState, const U32 mls)
|
|
{
|
|
size_t litLength;
|
|
size_t prevOffset;
|
|
size_t offset;
|
|
size_t matchLength;
|
|
const BYTE* dumps = seqState->dumps;
|
|
const BYTE* const de = seqState->dumpsEnd;
|
|
|
|
/* Literal length */
|
|
litLength = FSE_peakSymbol(&(seqState->stateLL));
|
|
prevOffset = litLength ? seq->offset : seqState->prevOffset;
|
|
if (litLength == MaxLL) {
|
|
U32 add = *dumps++;
|
|
if (add < 255) litLength += add;
|
|
else {
|
|
litLength = MEM_readLE32(dumps) & 0xFFFFFF; /* no risk : dumps is always followed by seq tables > 1 byte */
|
|
if (litLength&1) litLength>>=1, dumps += 3;
|
|
else litLength = (U16)(litLength)>>1, dumps += 2;
|
|
}
|
|
if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */
|
|
}
|
|
|
|
/* Offset */
|
|
{
|
|
static const U32 offsetPrefix[MaxOff+1] = {
|
|
1 /*fake*/, 1, 2, 4, 8, 0x10, 0x20, 0x40, 0x80, 0x100,
|
|
0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000, 0x20000, 0x40000,
|
|
0x80000, 0x100000, 0x200000, 0x400000, 0x800000, 0x1000000, 0x2000000, 0x4000000, /*fake*/ 1, 1, 1, 1 };
|
|
U32 offsetCode = FSE_peakSymbol(&(seqState->stateOffb)); /* <= maxOff, by table construction */
|
|
U32 nbBits = offsetCode - 1;
|
|
if (offsetCode==0) nbBits = 0; /* cmove */
|
|
offset = offsetPrefix[offsetCode] + BIT_readBits(&(seqState->DStream), nbBits);
|
|
if (MEM_32bits()) BIT_reloadDStream(&(seqState->DStream));
|
|
if (offsetCode==0) offset = prevOffset; /* repcode, cmove */
|
|
if (offsetCode | !litLength) seqState->prevOffset = seq->offset; /* cmove */
|
|
FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream)); /* update */
|
|
}
|
|
|
|
/* Literal length update */
|
|
FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream)); /* update */
|
|
if (MEM_32bits()) BIT_reloadDStream(&(seqState->DStream));
|
|
|
|
/* MatchLength */
|
|
matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream));
|
|
if (matchLength == MaxML) {
|
|
U32 add = *dumps++;
|
|
if (add < 255) matchLength += add;
|
|
else {
|
|
matchLength = MEM_readLE32(dumps) & 0xFFFFFF; /* no pb : dumps is always followed by seq tables > 1 byte */
|
|
if (matchLength&1) matchLength>>=1, dumps += 3;
|
|
else matchLength = (U16)(matchLength)>>1, dumps += 2;
|
|
}
|
|
if (dumps >= de) dumps = de-1; /* late correction, to avoid read overflow (data is now corrupted anyway) */
|
|
}
|
|
matchLength += mls;
|
|
|
|
/* save result */
|
|
seq->litLength = litLength;
|
|
seq->offset = offset;
|
|
seq->matchLength = matchLength;
|
|
seqState->dumps = dumps;
|
|
|
|
#if 0 /* debug */
|
|
{
|
|
static U64 totalDecoded = 0;
|
|
printf("pos %6u : %3u literals & match %3u bytes at distance %6u \n",
|
|
(U32)(totalDecoded), (U32)litLength, (U32)matchLength, (U32)offset);
|
|
totalDecoded += litLength + matchLength;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
|
|
FORCE_INLINE size_t ZSTD_execSequence(BYTE* op,
|
|
BYTE* const oend, seq_t sequence,
|
|
const BYTE** litPtr, const BYTE* const litLimit_8,
|
|
const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd)
|
|
{
|
|
static const int dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 }; /* added */
|
|
static const int dec64table[] = { 8, 8, 8, 7, 8, 9,10,11 }; /* substracted */
|
|
BYTE* const oLitEnd = op + sequence.litLength;
|
|
const size_t sequenceLength = sequence.litLength + sequence.matchLength;
|
|
BYTE* const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */
|
|
BYTE* const oend_8 = oend-8;
|
|
const BYTE* const litEnd = *litPtr + sequence.litLength;
|
|
const BYTE* match = oLitEnd - sequence.offset;
|
|
|
|
/* check */
|
|
if (oLitEnd > oend_8) return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of 8 from oend */
|
|
if (oMatchEnd > oend) return ERROR(dstSize_tooSmall); /* overwrite beyond dst buffer */
|
|
if (litEnd > litLimit_8) return ERROR(corruption_detected); /* risk read beyond lit buffer */
|
|
|
|
/* copy Literals */
|
|
ZSTD_wildcopy(op, *litPtr, sequence.litLength); /* note : oLitEnd <= oend-8 : no risk of overwrite beyond oend */
|
|
op = oLitEnd;
|
|
*litPtr = litEnd; /* 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 - (base-match);
|
|
if (match + sequence.matchLength <= dictEnd) {
|
|
memmove(oLitEnd, match, sequence.matchLength);
|
|
return sequenceLength;
|
|
}
|
|
/* span extDict & currentPrefixSegment */
|
|
{
|
|
size_t length1 = dictEnd - match;
|
|
memmove(oLitEnd, match, length1);
|
|
op = oLitEnd + length1;
|
|
sequence.matchLength -= length1;
|
|
match = base;
|
|
} }
|
|
|
|
/* match within prefix */
|
|
if (sequence.offset < 8) {
|
|
/* close range match, overlap */
|
|
const int 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-(16-3)) { // 3 = MINMATCH
|
|
if (op < oend_8) {
|
|
ZSTD_wildcopy(op, match, oend_8 - op);
|
|
match += oend_8 - op;
|
|
op = oend_8;
|
|
}
|
|
while (op < oMatchEnd)
|
|
*op++ = *match++;
|
|
} else {
|
|
ZSTD_wildcopy(op, match, 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* op = ostart;
|
|
BYTE* const oend = ostart + maxDstSize;
|
|
size_t errorCode, dumpsLength;
|
|
const BYTE* litPtr = dctx->litPtr;
|
|
const BYTE* const litLimit_8 = litPtr + dctx->litBufSize - 8;
|
|
const BYTE* const litEnd = litPtr + dctx->litSize;
|
|
int nbSeq;
|
|
const BYTE* dumps;
|
|
U32* DTableLL = dctx->LLTable;
|
|
U32* DTableML = dctx->MLTable;
|
|
U32* DTableOffb = dctx->OffTable;
|
|
const BYTE* const base = (const BYTE*) (dctx->base);
|
|
const BYTE* const vBase = (const BYTE*) (dctx->vBase);
|
|
const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
|
|
const U32 mls = dctx->params.searchLength;
|
|
|
|
/* Build Decoding Tables */
|
|
errorCode = ZSTD_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength,
|
|
DTableLL, DTableML, DTableOffb,
|
|
ip, seqSize);
|
|
if (ZSTD_isError(errorCode)) return errorCode;
|
|
ip += errorCode;
|
|
|
|
/* Regen sequences */
|
|
if (nbSeq) {
|
|
seq_t sequence;
|
|
seqState_t seqState;
|
|
|
|
memset(&sequence, 0, sizeof(sequence));
|
|
sequence.offset = REPCODE_STARTVALUE;
|
|
seqState.dumps = dumps;
|
|
seqState.dumpsEnd = dumps + dumpsLength;
|
|
seqState.prevOffset = REPCODE_STARTVALUE;
|
|
errorCode = BIT_initDStream(&(seqState.DStream), ip, iend-ip);
|
|
if (ERR_isError(errorCode)) return ERROR(corruption_detected);
|
|
FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL);
|
|
FSE_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb);
|
|
FSE_initDState(&(seqState.stateML), &(seqState.DStream), DTableML);
|
|
|
|
for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; ) {
|
|
size_t oneSeqSize;
|
|
nbSeq--;
|
|
ZSTD_decodeSequence(&sequence, &seqState, mls);
|
|
oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litLimit_8, base, vBase, dictEnd);
|
|
if (ZSTD_isError(oneSeqSize))
|
|
return oneSeqSize;
|
|
op += oneSeqSize;
|
|
}
|
|
|
|
/* check if reached exact end */
|
|
if (nbSeq) return ERROR(corruption_detected);
|
|
}
|
|
|
|
/* last literal segment */
|
|
{
|
|
size_t lastLLSize = litEnd - litPtr;
|
|
if (litPtr > litEnd) return ERROR(corruption_detected); /* too many literals already used */
|
|
if (op+lastLLSize > oend) return ERROR(dstSize_tooSmall);
|
|
memcpy(op, litPtr, lastLLSize);
|
|
op += lastLLSize;
|
|
}
|
|
|
|
return op-ostart;
|
|
}
|
|
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
|
|
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;
|
|
size_t litCSize;
|
|
|
|
if (srcSize >= BLOCKSIZE) return ERROR(srcSize_wrong);
|
|
|
|
ZSTD_LOG_BLOCK("%p: ZSTD_decompressBlock_internal searchLength=%d\n", dctx->base, dctx->params.searchLength);
|
|
|
|
/* Decode literals sub-block */
|
|
litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
|
|
if (ZSTD_isError(litCSize)) return litCSize;
|
|
ip += litCSize;
|
|
srcSize -= litCSize;
|
|
|
|
return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize);
|
|
}
|
|
|
|
|
|
size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
ZSTD_checkContinuity(dctx, dst);
|
|
return ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize);
|
|
}
|
|
|
|
|
|
/*! ZSTD_decompress_continueDCtx
|
|
* dctx must have been properly initialized */
|
|
static size_t ZSTD_decompress_continueDCtx(ZSTD_DCtx* dctx,
|
|
void* dst, size_t maxDstSize,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
const BYTE* ip = (const BYTE*)src;
|
|
const BYTE* iend = ip + srcSize;
|
|
BYTE* const ostart = (BYTE* const)dst;
|
|
BYTE* op = ostart;
|
|
BYTE* const oend = ostart + maxDstSize;
|
|
size_t remainingSize = srcSize;
|
|
blockProperties_t blockProperties;
|
|
|
|
/* Frame Header */
|
|
{
|
|
size_t frameHeaderSize;
|
|
if (srcSize < ZSTD_frameHeaderSize_min+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
|
|
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
|
|
{
|
|
const U32 magicNumber = MEM_readLE32(src);
|
|
if (ZSTD_isLegacy(magicNumber))
|
|
return ZSTD_decompressLegacy(dst, maxDstSize, src, srcSize, magicNumber);
|
|
}
|
|
#endif
|
|
frameHeaderSize = ZSTD_decodeFrameHeader_Part1(dctx, src, ZSTD_frameHeaderSize_min);
|
|
if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
|
|
if (srcSize < frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
|
|
ip += frameHeaderSize; remainingSize -= frameHeaderSize;
|
|
frameHeaderSize = ZSTD_decodeFrameHeader_Part2(dctx, src, frameHeaderSize);
|
|
if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
|
|
}
|
|
|
|
/* Loop on each block */
|
|
while (1)
|
|
{
|
|
size_t decodedSize=0;
|
|
size_t cBlockSize = ZSTD_getcBlockSize(ip, iend-ip, &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 :
|
|
return ERROR(GENERIC); /* not yet supported */
|
|
break;
|
|
case bt_end :
|
|
/* end of frame */
|
|
if (remainingSize) return ERROR(srcSize_wrong);
|
|
break;
|
|
default:
|
|
return ERROR(GENERIC); /* impossible */
|
|
}
|
|
if (cBlockSize == 0) break; /* bt_end */
|
|
|
|
if (ZSTD_isError(decodedSize)) return decodedSize;
|
|
op += decodedSize;
|
|
ip += cBlockSize;
|
|
remainingSize -= cBlockSize;
|
|
}
|
|
|
|
return op-ostart;
|
|
}
|
|
|
|
|
|
size_t ZSTD_decompress_usingPreparedDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* refDCtx,
|
|
void* dst, size_t maxDstSize,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
ZSTD_copyDCtx(dctx, refDCtx);
|
|
ZSTD_checkContinuity(dctx, dst);
|
|
return ZSTD_decompress_continueDCtx(dctx, dst, maxDstSize, src, srcSize);
|
|
}
|
|
|
|
|
|
size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
|
|
void* dst, size_t maxDstSize,
|
|
const void* src, size_t srcSize,
|
|
const void* dict, size_t dictSize)
|
|
{
|
|
ZSTD_decompressBegin_usingDict(dctx, dict, dictSize);
|
|
ZSTD_LOG_BLOCK("%p: ZSTD_decompressBegin_usingDict searchLength=%d\n", dctx->base, dctx->params.searchLength);
|
|
ZSTD_checkContinuity(dctx, dst);
|
|
return ZSTD_decompress_continueDCtx(dctx, dst, maxDstSize, src, srcSize);
|
|
}
|
|
|
|
|
|
size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize)
|
|
{
|
|
return ZSTD_decompress_usingDict(dctx, dst, maxDstSize, src, srcSize, NULL, 0);
|
|
}
|
|
|
|
size_t ZSTD_decompress(void* dst, size_t maxDstSize, const void* src, size_t srcSize)
|
|
{
|
|
#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE==1)
|
|
size_t regenSize;
|
|
ZSTD_DCtx* dctx = ZSTD_createDCtx();
|
|
if (dctx==NULL) return ERROR(memory_allocation);
|
|
regenSize = ZSTD_decompressDCtx(dctx, dst, maxDstSize, src, srcSize);
|
|
ZSTD_freeDCtx(dctx);
|
|
return regenSize;
|
|
#else
|
|
ZSTD_DCtx dctx;
|
|
return ZSTD_decompressDCtx(&dctx, dst, maxDstSize, src, srcSize);
|
|
#endif
|
|
}
|
|
|
|
|
|
/* ******************************
|
|
* Streaming Decompression API
|
|
********************************/
|
|
size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx)
|
|
{
|
|
return dctx->expected;
|
|
}
|
|
|
|
size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize)
|
|
{
|
|
/* Sanity check */
|
|
if (srcSize != dctx->expected) return ERROR(srcSize_wrong);
|
|
ZSTD_checkContinuity(dctx, dst);
|
|
|
|
/* Decompress : frame header; part 1 */
|
|
switch (dctx->stage)
|
|
{
|
|
case ZSTDds_getFrameHeaderSize :
|
|
{
|
|
/* get frame header size */
|
|
if (srcSize != ZSTD_frameHeaderSize_min) return ERROR(srcSize_wrong); /* impossible */
|
|
dctx->headerSize = ZSTD_decodeFrameHeader_Part1(dctx, src, ZSTD_frameHeaderSize_min);
|
|
if (ZSTD_isError(dctx->headerSize)) return dctx->headerSize;
|
|
memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_min);
|
|
if (dctx->headerSize > ZSTD_frameHeaderSize_min) {
|
|
dctx->expected = dctx->headerSize - ZSTD_frameHeaderSize_min;
|
|
dctx->stage = ZSTDds_decodeFrameHeader;
|
|
return 0;
|
|
}
|
|
dctx->expected = 0; /* not necessary to copy more */
|
|
}
|
|
case ZSTDds_decodeFrameHeader:
|
|
{
|
|
/* get frame header */
|
|
size_t result;
|
|
memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_min, src, dctx->expected);
|
|
result = ZSTD_decodeFrameHeader_Part2(dctx, dctx->headerBuffer, dctx->headerSize);
|
|
if (ZSTD_isError(result)) return result;
|
|
dctx->expected = ZSTD_blockHeaderSize;
|
|
dctx->stage = ZSTDds_decodeBlockHeader;
|
|
return 0;
|
|
}
|
|
case ZSTDds_decodeBlockHeader:
|
|
{
|
|
/* Decode block header */
|
|
blockProperties_t bp;
|
|
size_t blockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp);
|
|
if (ZSTD_isError(blockSize)) return blockSize;
|
|
if (bp.blockType == bt_end) {
|
|
dctx->expected = 0;
|
|
dctx->stage = ZSTDds_getFrameHeaderSize;
|
|
}
|
|
else {
|
|
dctx->expected = blockSize;
|
|
dctx->bType = bp.blockType;
|
|
dctx->stage = ZSTDds_decompressBlock;
|
|
}
|
|
return 0;
|
|
}
|
|
case ZSTDds_decompressBlock:
|
|
{
|
|
/* Decompress : block content */
|
|
size_t rSize;
|
|
switch(dctx->bType)
|
|
{
|
|
case bt_compressed:
|
|
rSize = ZSTD_decompressBlock_internal(dctx, dst, maxDstSize, src, srcSize);
|
|
break;
|
|
case bt_raw :
|
|
rSize = ZSTD_copyRawBlock(dst, maxDstSize, src, srcSize);
|
|
break;
|
|
case bt_rle :
|
|
return ERROR(GENERIC); /* not yet handled */
|
|
break;
|
|
case bt_end : /* should never happen (filtered at phase 1) */
|
|
rSize = 0;
|
|
break;
|
|
default:
|
|
return ERROR(GENERIC); /* impossible */
|
|
}
|
|
dctx->stage = ZSTDds_decodeBlockHeader;
|
|
dctx->expected = ZSTD_blockHeaderSize;
|
|
dctx->previousDstEnd = (char*)dst + rSize;
|
|
return rSize;
|
|
}
|
|
default:
|
|
return ERROR(GENERIC); /* impossible */
|
|
}
|
|
}
|
|
|
|
|
|
static void 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;
|
|
}
|
|
|
|
static size_t ZSTD_loadEntropy(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
|
|
{
|
|
size_t hSize, offcodeHeaderSize, matchlengthHeaderSize, errorCode, litlengthHeaderSize;
|
|
short offcodeNCount[MaxOff+1];
|
|
U32 offcodeMaxValue=MaxOff, offcodeLog=OffFSELog;
|
|
short matchlengthNCount[MaxML+1];
|
|
unsigned matchlengthMaxValue = MaxML, matchlengthLog = MLFSELog;
|
|
short litlengthNCount[MaxLL+1];
|
|
unsigned litlengthMaxValue = MaxLL, litlengthLog = LLFSELog;
|
|
|
|
hSize = HUF_readDTableX4(dctx->hufTableX4, dict, dictSize);
|
|
if (HUF_isError(hSize)) return ERROR(dictionary_corrupted);
|
|
dict = (const char*)dict + hSize;
|
|
dictSize -= hSize;
|
|
|
|
offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dict, dictSize);
|
|
if (FSE_isError(offcodeHeaderSize)) return ERROR(dictionary_corrupted);
|
|
errorCode = FSE_buildDTable(dctx->OffTable, offcodeNCount, offcodeMaxValue, offcodeLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted);
|
|
dict = (const char*)dict + offcodeHeaderSize;
|
|
dictSize -= offcodeHeaderSize;
|
|
|
|
matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dict, dictSize);
|
|
if (FSE_isError(matchlengthHeaderSize)) return ERROR(dictionary_corrupted);
|
|
errorCode = FSE_buildDTable(dctx->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted);
|
|
dict = (const char*)dict + matchlengthHeaderSize;
|
|
dictSize -= matchlengthHeaderSize;
|
|
|
|
litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dict, dictSize);
|
|
if (FSE_isError(litlengthHeaderSize)) return ERROR(dictionary_corrupted);
|
|
errorCode = FSE_buildDTable(dctx->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted);
|
|
|
|
dctx->flagStaticTables = 1;
|
|
return hSize + offcodeHeaderSize + matchlengthHeaderSize + litlengthHeaderSize;
|
|
}
|
|
|
|
static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
|
|
{
|
|
size_t eSize;
|
|
U32 magic = MEM_readLE32(dict);
|
|
if (magic != ZSTD_DICT_MAGIC) {
|
|
/* pure content mode */
|
|
ZSTD_refDictContent(dctx, dict, dictSize);
|
|
return 0;
|
|
}
|
|
/* load entropy tables */
|
|
dict = (const char*)dict + 4;
|
|
dictSize -= 4;
|
|
eSize = ZSTD_loadEntropy(dctx, dict, dictSize);
|
|
if (ZSTD_isError(eSize)) return ERROR(dictionary_corrupted);
|
|
|
|
/* reference dictionary content */
|
|
dict = (const char*)dict + eSize;
|
|
dictSize -= eSize;
|
|
ZSTD_refDictContent(dctx, dict, dictSize);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
|
|
{
|
|
size_t errorCode;
|
|
errorCode = ZSTD_decompressBegin(dctx);
|
|
if (ZSTD_isError(errorCode)) return errorCode;
|
|
|
|
if (dict && dictSize) {
|
|
errorCode = ZSTD_decompress_insertDictionary(dctx, dict, dictSize);
|
|
if (ZSTD_isError(errorCode)) return ERROR(dictionary_corrupted);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|