1563 lines
62 KiB
C
1563 lines
62 KiB
C
/**
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* Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under the BSD-style license found in the
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* LICENSE file in the root directory of this source tree. An additional grant
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* of patent rights can be found in the PATENTS file in the same directory.
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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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* MAXWINDOWSIZE_DEFAULT :
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* maximum window size accepted by DStream, by default.
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* Frames requiring more memory will be rejected.
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*/
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#ifndef ZSTD_MAXWINDOWSIZE_DEFAULT
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# define ZSTD_MAXWINDOWSIZE_DEFAULT (257 << 20) /* 257 MB */
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#endif
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/*-*******************************************************
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* Dependencies
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*********************************************************/
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#include <string.h> /* memcpy, memmove, memset */
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#include "mem.h" /* low level memory routines */
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#define XXH_STATIC_LINKING_ONLY /* XXH64_state_t */
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#include "xxhash.h" /* XXH64_* */
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#define FSE_STATIC_LINKING_ONLY
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#include "fse.h"
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#define HUF_STATIC_LINKING_ONLY
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#include "huf.h"
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#include "zstd_internal.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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* Macros
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***************************************/
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#define ZSTD_isError ERR_isError /* for inlining */
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#define FSE_isError ERR_isError
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#define HUF_isError ERR_isError
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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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* Context management
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***************************************************************/
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typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader,
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ZSTDds_decodeBlockHeader, ZSTDds_decompressBlock,
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ZSTDds_decompressLastBlock, ZSTDds_checkChecksum,
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ZSTDds_decodeSkippableHeader, ZSTDds_skipFrame } 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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HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */
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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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U32 rep[ZSTD_REP_NUM];
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ZSTD_frameParams fParams;
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blockType_e 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 litEntropy;
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U32 fseEntropy;
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XXH64_state_t xxhState;
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size_t headerSize;
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U32 dictID;
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const BYTE* litPtr;
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ZSTD_customMem customMem;
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size_t litBufSize;
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size_t litSize;
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size_t rleSize;
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BYTE litBuffer[ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH];
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BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
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}; /* typedef'd to ZSTD_DCtx within "zstd.h" */
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size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx) { return sizeof(*dctx); }
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size_t ZSTD_estimateDCtxSize(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_prefix;
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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->hufTable[0] = (HUF_DTable)((HufLog)*0x1000001);
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dctx->litEntropy = dctx->fseEntropy = 0;
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dctx->dictID = 0;
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MEM_STATIC_ASSERT(sizeof(dctx->rep)==sizeof(repStartValue));
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memcpy(dctx->rep, repStartValue, sizeof(repStartValue));
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return 0;
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}
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ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
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{
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ZSTD_DCtx* dctx;
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if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
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if (!customMem.customAlloc || !customMem.customFree) return NULL;
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dctx = (ZSTD_DCtx*) ZSTD_malloc(sizeof(ZSTD_DCtx), customMem);
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if (!dctx) return NULL;
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memcpy(&dctx->customMem, &customMem, sizeof(customMem));
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ZSTD_decompressBegin(dctx);
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return dctx;
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}
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ZSTD_DCtx* ZSTD_createDCtx(void)
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{
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return ZSTD_createDCtx_advanced(defaultCustomMem);
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}
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size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx)
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{
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if (dctx==NULL) return 0; /* support free on NULL */
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ZSTD_free(dctx, dctx->customMem);
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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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size_t const workSpaceSize = (ZSTD_BLOCKSIZE_ABSOLUTEMAX+WILDCOPY_OVERLENGTH) + ZSTD_frameHeaderSize_max;
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memcpy(dstDCtx, srcDCtx, sizeof(ZSTD_DCtx) - workSpaceSize); /* 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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/* See compression format details in : zstd_compression_format.md */
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/** ZSTD_frameHeaderSize() :
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* srcSize must be >= ZSTD_frameHeaderSize_prefix.
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* @return : size of the Frame Header */
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static size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
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{
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if (srcSize < ZSTD_frameHeaderSize_prefix) return ERROR(srcSize_wrong);
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{ BYTE const fhd = ((const BYTE*)src)[4];
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U32 const dictID= fhd & 3;
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U32 const singleSegment = (fhd >> 5) & 1;
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U32 const fcsId = fhd >> 6;
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return ZSTD_frameHeaderSize_prefix + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId]
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+ (singleSegment && !fcsId);
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}
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}
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/** ZSTD_getFrameParams() :
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* decode Frame Header, or require larger `srcSize`.
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* @return : 0, `fparamsPtr` is correctly filled,
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* >0, `srcSize` is too small, result is expected `srcSize`,
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* or an error code, which can be tested using ZSTD_isError() */
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size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t srcSize)
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{
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const BYTE* ip = (const BYTE*)src;
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if (srcSize < ZSTD_frameHeaderSize_prefix) return ZSTD_frameHeaderSize_prefix;
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if (MEM_readLE32(src) != ZSTD_MAGICNUMBER) {
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if ((MEM_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) {
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if (srcSize < ZSTD_skippableHeaderSize) return ZSTD_skippableHeaderSize; /* magic number + skippable frame length */
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memset(fparamsPtr, 0, sizeof(*fparamsPtr));
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fparamsPtr->frameContentSize = MEM_readLE32((const char *)src + 4);
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fparamsPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */
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return 0;
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}
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return ERROR(prefix_unknown);
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}
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/* ensure there is enough `srcSize` to fully read/decode frame header */
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{ size_t const fhsize = ZSTD_frameHeaderSize(src, srcSize);
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if (srcSize < fhsize) return fhsize; }
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{ BYTE const fhdByte = ip[4];
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size_t pos = 5;
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U32 const dictIDSizeCode = fhdByte&3;
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U32 const checksumFlag = (fhdByte>>2)&1;
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U32 const singleSegment = (fhdByte>>5)&1;
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U32 const fcsID = fhdByte>>6;
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U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX;
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U32 windowSize = 0;
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U32 dictID = 0;
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U64 frameContentSize = 0;
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if ((fhdByte & 0x08) != 0) return ERROR(frameParameter_unsupported); /* reserved bits, which must be zero */
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if (!singleSegment) {
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BYTE const wlByte = ip[pos++];
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U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
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if (windowLog > ZSTD_WINDOWLOG_MAX) return ERROR(frameParameter_unsupported);
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windowSize = (1U << windowLog);
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windowSize += (windowSize >> 3) * (wlByte&7);
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}
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switch(dictIDSizeCode)
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{
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default: /* impossible */
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case 0 : break;
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case 1 : dictID = ip[pos]; pos++; break;
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case 2 : dictID = MEM_readLE16(ip+pos); pos+=2; break;
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case 3 : dictID = MEM_readLE32(ip+pos); pos+=4; break;
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}
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switch(fcsID)
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{
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default: /* impossible */
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case 0 : if (singleSegment) frameContentSize = ip[pos]; break;
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case 1 : frameContentSize = MEM_readLE16(ip+pos)+256; break;
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case 2 : frameContentSize = MEM_readLE32(ip+pos); break;
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case 3 : frameContentSize = MEM_readLE64(ip+pos); break;
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}
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if (!windowSize) windowSize = (U32)frameContentSize;
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if (windowSize > windowSizeMax) return ERROR(frameParameter_unsupported);
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fparamsPtr->frameContentSize = frameContentSize;
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fparamsPtr->windowSize = windowSize;
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fparamsPtr->dictID = dictID;
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fparamsPtr->checksumFlag = checksumFlag;
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}
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return 0;
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}
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/** ZSTD_getDecompressedSize() :
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* compatible with legacy mode
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* @return : decompressed size if known, 0 otherwise
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note : 0 can mean any of the following :
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- decompressed size is not present within frame header
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- frame header unknown / not supported
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- frame header not complete (`srcSize` too small) */
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unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize)
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{
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#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
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if (ZSTD_isLegacy(src, srcSize)) return ZSTD_getDecompressedSize_legacy(src, srcSize);
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#endif
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{ ZSTD_frameParams fparams;
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size_t const frResult = ZSTD_getFrameParams(&fparams, src, srcSize);
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if (frResult!=0) return 0;
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return fparams.frameContentSize;
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}
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}
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/** ZSTD_decodeFrameHeader() :
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* `srcSize` must be the size provided by ZSTD_frameHeaderSize().
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* @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */
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static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx* dctx, const void* src, size_t srcSize)
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{
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size_t const result = ZSTD_getFrameParams(&(dctx->fParams), src, srcSize);
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if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID)) return ERROR(dictionary_wrong);
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if (dctx->fParams.checksumFlag) XXH64_reset(&dctx->xxhState, 0);
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return result;
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}
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typedef struct
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{
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blockType_e blockType;
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U32 lastBlock;
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U32 origSize;
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} blockProperties_t;
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/*! ZSTD_getcBlockSize() :
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* Provides the size of compressed block from block header `src` */
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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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if (srcSize < ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
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{ U32 const cBlockHeader = MEM_readLE24(src);
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U32 const cSize = cBlockHeader >> 3;
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bpPtr->lastBlock = cBlockHeader & 1;
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bpPtr->blockType = (blockType_e)((cBlockHeader >> 1) & 3);
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bpPtr->origSize = cSize; /* only useful for RLE */
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if (bpPtr->blockType == bt_rle) return 1;
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if (bpPtr->blockType == bt_reserved) return ERROR(corruption_detected);
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return cSize;
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}
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}
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static size_t ZSTD_copyRawBlock(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
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{
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if (srcSize > dstCapacity) 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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static size_t ZSTD_setRleBlock(void* dst, size_t dstCapacity, const void* src, size_t srcSize, size_t regenSize)
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{
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if (srcSize != 1) return ERROR(srcSize_wrong);
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if (regenSize > dstCapacity) return ERROR(dstSize_tooSmall);
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memset(dst, *(const BYTE*)src, regenSize);
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return regenSize;
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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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if (srcSize < MIN_CBLOCK_SIZE) return ERROR(corruption_detected);
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{ const BYTE* const istart = (const BYTE*) src;
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symbolEncodingType_e const litEncType = (symbolEncodingType_e)(istart[0] & 3);
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switch(litEncType)
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{
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case set_repeat:
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if (dctx->litEntropy==0) return ERROR(dictionary_corrupted);
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/* fall-through */
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case set_compressed:
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if (srcSize < 5) return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3 */
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{ size_t lhSize, litSize, litCSize;
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U32 singleStream=0;
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U32 const lhlCode = (istart[0] >> 2) & 3;
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U32 const lhc = MEM_readLE32(istart);
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switch(lhlCode)
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{
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case 0: case 1: default: /* note : default is impossible, since lhlCode into [0..3] */
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/* 2 - 2 - 10 - 10 */
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{ singleStream = !lhlCode;
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lhSize = 3;
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litSize = (lhc >> 4) & 0x3FF;
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litCSize = (lhc >> 14) & 0x3FF;
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break;
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}
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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 = (lhc >> 4) & 0x3FFF;
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litCSize = lhc >> 18;
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break;
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}
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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 = (lhc >> 4) & 0x3FFFF;
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litCSize = (lhc >> 22) + (istart[4] << 10);
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break;
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}
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}
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if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(corruption_detected);
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if (litCSize + lhSize > srcSize) return ERROR(corruption_detected);
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if (HUF_isError((litEncType==set_repeat) ?
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( singleStream ?
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HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->hufTable) :
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HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart+lhSize, litCSize, dctx->hufTable) ) :
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( singleStream ?
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HUF_decompress1X2_DCtx(dctx->hufTable, dctx->litBuffer, litSize, istart+lhSize, litCSize) :
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HUF_decompress4X_hufOnly (dctx->hufTable, 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 = ZSTD_BLOCKSIZE_ABSOLUTEMAX+WILDCOPY_OVERLENGTH;
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dctx->litSize = litSize;
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dctx->litEntropy = 1;
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return litCSize + lhSize;
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}
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case set_basic:
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{ size_t litSize, lhSize;
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U32 const lhlCode = ((istart[0]) >> 2) & 3;
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switch(lhlCode)
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{
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case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */
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lhSize = 1;
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litSize = istart[0] >> 3;
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break;
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case 1:
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lhSize = 2;
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litSize = MEM_readLE16(istart) >> 4;
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break;
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case 3:
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lhSize = 3;
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litSize = MEM_readLE24(istart) >> 4;
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break;
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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 = ZSTD_BLOCKSIZE_ABSOLUTEMAX+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 set_rle:
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{ U32 const lhlCode = ((istart[0]) >> 2) & 3;
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size_t litSize, lhSize;
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switch(lhlCode)
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{
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case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */
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lhSize = 1;
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litSize = istart[0] >> 3;
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break;
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case 1:
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lhSize = 2;
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litSize = MEM_readLE16(istart) >> 4;
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break;
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case 3:
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lhSize = 3;
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litSize = MEM_readLE24(istart) >> 4;
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if (srcSize<4) return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */
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break;
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}
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if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(corruption_detected);
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memset(dctx->litBuffer, istart[lhSize], litSize);
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dctx->litPtr = dctx->litBuffer;
|
|
dctx->litBufSize = ZSTD_BLOCKSIZE_ABSOLUTEMAX+WILDCOPY_OVERLENGTH;
|
|
dctx->litSize = litSize;
|
|
return lhSize+1;
|
|
}
|
|
default:
|
|
return ERROR(corruption_detected); /* impossible */
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
|
|
/*! ZSTD_buildSeqTable() :
|
|
@return : nb bytes read from src,
|
|
or an error code if it fails, testable with ZSTD_isError()
|
|
*/
|
|
FORCE_INLINE size_t ZSTD_buildSeqTable(FSE_DTable* DTable, symbolEncodingType_e type, U32 max, U32 maxLog,
|
|
const void* src, size_t srcSize,
|
|
const S16* defaultNorm, U32 defaultLog, U32 flagRepeatTable)
|
|
{
|
|
switch(type)
|
|
{
|
|
case set_rle :
|
|
if (!srcSize) return ERROR(srcSize_wrong);
|
|
if ( (*(const BYTE*)src) > max) return ERROR(corruption_detected);
|
|
FSE_buildDTable_rle(DTable, *(const BYTE*)src); /* if *src > max, data is corrupted */
|
|
return 1;
|
|
case set_basic :
|
|
FSE_buildDTable(DTable, defaultNorm, max, defaultLog);
|
|
return 0;
|
|
case set_repeat:
|
|
if (!flagRepeatTable) return ERROR(corruption_detected);
|
|
return 0;
|
|
default : /* impossible */
|
|
case set_compressed :
|
|
{ U32 tableLog;
|
|
S16 norm[MaxSeq+1];
|
|
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(DTable, norm, max, tableLog);
|
|
return headerSize;
|
|
} }
|
|
}
|
|
|
|
|
|
size_t ZSTD_decodeSeqHeaders(int* nbSeqPtr,
|
|
FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb, U32 flagRepeatTable,
|
|
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)
|
|
nbSeq = MEM_readLE16(ip) + LONGNBSEQ, ip+=2;
|
|
else
|
|
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(DTableLL, LLtype, MaxLL, LLFSELog, ip, iend-ip, LL_defaultNorm, LL_defaultNormLog, flagRepeatTable);
|
|
if (ZSTD_isError(llhSize)) return ERROR(corruption_detected);
|
|
ip += llhSize;
|
|
}
|
|
{ size_t const ofhSize = ZSTD_buildSeqTable(DTableOffb, OFtype, MaxOff, OffFSELog, ip, iend-ip, OF_defaultNorm, OF_defaultNormLog, flagRepeatTable);
|
|
if (ZSTD_isError(ofhSize)) return ERROR(corruption_detected);
|
|
ip += ofhSize;
|
|
}
|
|
{ size_t const mlhSize = ZSTD_buildSeqTable(DTableML, MLtype, MaxML, MLFSELog, ip, iend-ip, ML_defaultNorm, ML_defaultNormLog, flagRepeatTable);
|
|
if (ZSTD_isError(mlhSize)) return ERROR(corruption_detected);
|
|
ip += mlhSize;
|
|
} }
|
|
|
|
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[ZSTD_REP_NUM];
|
|
} seqState_t;
|
|
|
|
|
|
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_readBits(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
|
|
if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream);
|
|
}
|
|
|
|
if (ofCode <= 1) {
|
|
offset += (llCode==0);
|
|
if (offset) {
|
|
size_t const temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
|
|
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_readBits(&seqState->DStream, mlBits) : 0); /* <= 16 bits */
|
|
if (MEM_32bits() && (mlBits+llBits>24)) BIT_reloadDStream(&seqState->DStream);
|
|
|
|
seq.litLength = LL_base[llCode] + ((llCode>15) ? BIT_readBits(&seqState->DStream, llBits) : 0); /* <= 16 bits */
|
|
if (MEM_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 (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
|
|
FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */
|
|
|
|
return seq;
|
|
}
|
|
|
|
|
|
FORCE_INLINE
|
|
size_t ZSTD_execSequence(BYTE* op,
|
|
BYTE* const oend, seq_t sequence,
|
|
const BYTE** litPtr, const BYTE* const litLimit_w,
|
|
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 ((oLitEnd>oend_w) | (oMatchEnd>oend)) return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */
|
|
if (iLitEnd > litLimit_w) return ERROR(corruption_detected); /* over-read beyond lit buffer */
|
|
|
|
/* 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 - (base-match);
|
|
if (match + sequence.matchLength <= dictEnd) {
|
|
memmove(oLitEnd, match, sequence.matchLength);
|
|
return sequenceLength;
|
|
}
|
|
/* span extDict & currentPrefixSegment */
|
|
{ size_t const 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 */
|
|
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 }; /* substracted */
|
|
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, 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 litLimit_w = litPtr + dctx->litBufSize - WILDCOPY_OVERLENGTH;
|
|
const BYTE* const litEnd = litPtr + dctx->litSize;
|
|
FSE_DTable* DTableLL = dctx->LLTable;
|
|
FSE_DTable* DTableML = dctx->MLTable;
|
|
FSE_DTable* 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);
|
|
int nbSeq;
|
|
|
|
/* Build Decoding Tables */
|
|
{ size_t const seqHSize = ZSTD_decodeSeqHeaders(&nbSeq, DTableLL, DTableML, DTableOffb, dctx->fseEntropy, 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->rep[i]; }
|
|
{ size_t const 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 ; ) {
|
|
nbSeq--;
|
|
{ seq_t const sequence = ZSTD_decodeSequence(&seqState);
|
|
size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litLimit_w, 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->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 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;
|
|
|
|
if (srcSize >= ZSTD_BLOCKSIZE_ABSOLUTEMAX) return ERROR(srcSize_wrong);
|
|
|
|
/* Decode literals sub-block */
|
|
{ size_t const 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)
|
|
{
|
|
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. */
|
|
ZSTDLIB_API 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_decompressFrame() :
|
|
* `dctx` must be properly initialized */
|
|
static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
const BYTE* ip = (const BYTE*)src;
|
|
BYTE* const ostart = (BYTE* const)dst;
|
|
BYTE* const oend = ostart + dstCapacity;
|
|
BYTE* op = ostart;
|
|
size_t remainingSize = srcSize;
|
|
|
|
/* check */
|
|
if (srcSize < ZSTD_frameHeaderSize_min+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
|
|
|
|
/* Frame Header */
|
|
{ size_t const frameHeaderSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_prefix);
|
|
size_t result;
|
|
if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
|
|
if (srcSize < frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
|
|
result = ZSTD_decodeFrameHeader(dctx, src, frameHeaderSize);
|
|
if (ZSTD_isError(result)) return result;
|
|
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 = MEM_readLE32(ip);
|
|
if (checkRead != checkCalc) return ERROR(checksum_wrong);
|
|
remainingSize -= 4;
|
|
}
|
|
|
|
if (remainingSize) return ERROR(srcSize_wrong);
|
|
return op-ostart;
|
|
}
|
|
|
|
|
|
/*! ZSTD_decompress_usingPreparedDCtx() :
|
|
* Same as ZSTD_decompress_usingDict, but using a reference context `preparedDCtx`, where dictionary has been loaded.
|
|
* It avoids reloading the dictionary each time.
|
|
* `preparedDCtx` must have been properly initialized using ZSTD_decompressBegin_usingDict().
|
|
* Requires 2 contexts : 1 for reference (preparedDCtx), which will not be modified, and 1 to run the decompression operation (dctx) */
|
|
size_t ZSTD_decompress_usingPreparedDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* refDCtx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize)
|
|
{
|
|
ZSTD_copyDCtx(dctx, refDCtx);
|
|
ZSTD_checkContinuity(dctx, dst);
|
|
return ZSTD_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
|
|
}
|
|
|
|
|
|
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)
|
|
{
|
|
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
|
|
if (ZSTD_isLegacy(src, srcSize)) return ZSTD_decompressLegacy(dst, dstCapacity, src, srcSize, dict, dictSize);
|
|
#endif
|
|
ZSTD_decompressBegin_usingDict(dctx, dict, dictSize);
|
|
ZSTD_checkContinuity(dctx, dst);
|
|
return ZSTD_decompressFrame(dctx, dst, dstCapacity, src, srcSize);
|
|
}
|
|
|
|
|
|
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);
|
|
}
|
|
|
|
|
|
size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
|
|
{
|
|
#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE==1)
|
|
size_t regenSize;
|
|
ZSTD_DCtx* const dctx = ZSTD_createDCtx();
|
|
if (dctx==NULL) return ERROR(memory_allocation);
|
|
regenSize = ZSTD_decompressDCtx(dctx, dst, dstCapacity, src, srcSize);
|
|
ZSTD_freeDCtx(dctx);
|
|
return regenSize;
|
|
#else /* stack mode */
|
|
ZSTD_DCtx dctx;
|
|
return ZSTD_decompressDCtx(&dctx, dst, dstCapacity, src, srcSize);
|
|
#endif
|
|
}
|
|
|
|
|
|
/*-**************************************
|
|
* 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 ((MEM_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:
|
|
{ size_t result;
|
|
memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
|
|
result = ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize);
|
|
if (ZSTD_isError(result)) return result;
|
|
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 = MEM_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 = MEM_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;
|
|
}
|
|
|
|
static size_t ZSTD_loadEntropy(ZSTD_DCtx* dctx, const void* const dict, size_t const dictSize)
|
|
{
|
|
const BYTE* dictPtr = (const BYTE*)dict;
|
|
const BYTE* const dictEnd = dictPtr + dictSize;
|
|
|
|
{ size_t const hSize = HUF_readDTableX4(dctx->hufTable, dict, dictSize);
|
|
if (HUF_isError(hSize)) return ERROR(dictionary_corrupted);
|
|
dictPtr += hSize;
|
|
}
|
|
|
|
{ short offcodeNCount[MaxOff+1];
|
|
U32 offcodeMaxValue=MaxOff, offcodeLog=OffFSELog;
|
|
size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd-dictPtr);
|
|
if (FSE_isError(offcodeHeaderSize)) return ERROR(dictionary_corrupted);
|
|
{ size_t const errorCode = FSE_buildDTable(dctx->OffTable, offcodeNCount, offcodeMaxValue, offcodeLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted); }
|
|
dictPtr += offcodeHeaderSize;
|
|
}
|
|
|
|
{ short matchlengthNCount[MaxML+1];
|
|
unsigned matchlengthMaxValue = MaxML, matchlengthLog = MLFSELog;
|
|
size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd-dictPtr);
|
|
if (FSE_isError(matchlengthHeaderSize)) return ERROR(dictionary_corrupted);
|
|
{ size_t const errorCode = FSE_buildDTable(dctx->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted); }
|
|
dictPtr += matchlengthHeaderSize;
|
|
}
|
|
|
|
{ short litlengthNCount[MaxLL+1];
|
|
unsigned litlengthMaxValue = MaxLL, litlengthLog = LLFSELog;
|
|
size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd-dictPtr);
|
|
if (FSE_isError(litlengthHeaderSize)) return ERROR(dictionary_corrupted);
|
|
{ size_t const errorCode = FSE_buildDTable(dctx->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog);
|
|
if (FSE_isError(errorCode)) return ERROR(dictionary_corrupted); }
|
|
dictPtr += litlengthHeaderSize;
|
|
}
|
|
|
|
if (dictPtr+12 > dictEnd) return ERROR(dictionary_corrupted);
|
|
dctx->rep[0] = MEM_readLE32(dictPtr+0); if (dctx->rep[0] >= dictSize) return ERROR(dictionary_corrupted);
|
|
dctx->rep[1] = MEM_readLE32(dictPtr+4); if (dctx->rep[1] >= dictSize) return ERROR(dictionary_corrupted);
|
|
dctx->rep[2] = MEM_readLE32(dictPtr+8); if (dctx->rep[2] >= dictSize) return ERROR(dictionary_corrupted);
|
|
dictPtr += 12;
|
|
|
|
dctx->litEntropy = dctx->fseEntropy = 1;
|
|
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 = MEM_readLE32(dict);
|
|
if (magic != ZSTD_DICT_MAGIC) {
|
|
return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */
|
|
} }
|
|
dctx->dictID = MEM_readLE32((const char*)dict + 4);
|
|
|
|
/* load entropy tables */
|
|
dict = (const char*)dict + 8;
|
|
dictSize -= 8;
|
|
{ size_t const eSize = ZSTD_loadEntropy(dctx, dict, dictSize);
|
|
if (ZSTD_isError(eSize)) return ERROR(dictionary_corrupted);
|
|
dict = (const char*)dict + eSize;
|
|
dictSize -= eSize;
|
|
}
|
|
|
|
/* reference dictionary content */
|
|
return ZSTD_refDictContent(dctx, dict, dictSize);
|
|
}
|
|
|
|
|
|
size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize)
|
|
{
|
|
{ size_t const errorCode = ZSTD_decompressBegin(dctx);
|
|
if (ZSTD_isError(errorCode)) return errorCode; }
|
|
|
|
if (dict && dictSize) {
|
|
size_t const errorCode = ZSTD_decompress_insertDictionary(dctx, dict, dictSize);
|
|
if (ZSTD_isError(errorCode)) return ERROR(dictionary_corrupted);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
struct ZSTD_DDict_s {
|
|
void* dict;
|
|
size_t dictSize;
|
|
ZSTD_DCtx* refContext;
|
|
}; /* typedef'd to ZSTD_DDict within "zstd.h" */
|
|
|
|
ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize, ZSTD_customMem customMem)
|
|
{
|
|
if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
|
|
if (!customMem.customAlloc || !customMem.customFree) return NULL;
|
|
|
|
{ ZSTD_DDict* const ddict = (ZSTD_DDict*) ZSTD_malloc(sizeof(ZSTD_DDict), customMem);
|
|
void* const dictContent = ZSTD_malloc(dictSize, customMem);
|
|
ZSTD_DCtx* const dctx = ZSTD_createDCtx_advanced(customMem);
|
|
|
|
if (!dictContent || !ddict || !dctx) {
|
|
ZSTD_free(dictContent, customMem);
|
|
ZSTD_free(ddict, customMem);
|
|
ZSTD_free(dctx, customMem);
|
|
return NULL;
|
|
}
|
|
|
|
memcpy(dictContent, dict, dictSize);
|
|
{ size_t const errorCode = ZSTD_decompressBegin_usingDict(dctx, dictContent, dictSize);
|
|
if (ZSTD_isError(errorCode)) {
|
|
ZSTD_free(dictContent, customMem);
|
|
ZSTD_free(ddict, customMem);
|
|
ZSTD_free(dctx, customMem);
|
|
return NULL;
|
|
} }
|
|
|
|
ddict->dict = dictContent;
|
|
ddict->dictSize = dictSize;
|
|
ddict->refContext = dctx;
|
|
return ddict;
|
|
}
|
|
}
|
|
|
|
/*! ZSTD_createDDict() :
|
|
* Create a digested dictionary, ready to start decompression without startup delay.
|
|
* `dict` can be released after `ZSTD_DDict` creation */
|
|
ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
|
|
{
|
|
ZSTD_customMem const allocator = { NULL, NULL, NULL };
|
|
return ZSTD_createDDict_advanced(dict, dictSize, allocator);
|
|
}
|
|
|
|
size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
|
|
{
|
|
if (ddict==NULL) return 0; /* support free on NULL */
|
|
{ ZSTD_customMem const cMem = ddict->refContext->customMem;
|
|
ZSTD_freeDCtx(ddict->refContext);
|
|
ZSTD_free(ddict->dict, cMem);
|
|
ZSTD_free(ddict, cMem);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*! ZSTD_decompress_usingDDict() :
|
|
* Decompression using a pre-digested Dictionary
|
|
* Use dictionary without significant overhead. */
|
|
ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize,
|
|
const ZSTD_DDict* ddict)
|
|
{
|
|
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT==1)
|
|
if (ZSTD_isLegacy(src, srcSize)) return ZSTD_decompressLegacy(dst, dstCapacity, src, srcSize, ddict->dict, ddict->dictSize);
|
|
#endif
|
|
return ZSTD_decompress_usingPreparedDCtx(dctx, ddict->refContext,
|
|
dst, dstCapacity,
|
|
src, srcSize);
|
|
}
|
|
|
|
|
|
/*=====================================
|
|
* Streaming decompression
|
|
*====================================*/
|
|
|
|
typedef enum { zdss_init, zdss_loadHeader,
|
|
zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage;
|
|
|
|
/* *** Resource management *** */
|
|
struct ZSTD_DStream_s {
|
|
ZSTD_DCtx* zd;
|
|
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];
|
|
size_t lhSize;
|
|
ZSTD_customMem customMem;
|
|
void* dictContent;
|
|
size_t dictSize;
|
|
const void* dictSource;
|
|
void* legacyContext;
|
|
U32 previousLegacyVersion;
|
|
U32 legacyVersion;
|
|
}; /* typedef'd to ZSTD_DStream within "zstd.h" */
|
|
|
|
|
|
ZSTD_DStream* ZSTD_createDStream(void)
|
|
{
|
|
return ZSTD_createDStream_advanced(defaultCustomMem);
|
|
}
|
|
|
|
ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem)
|
|
{
|
|
ZSTD_DStream* zds;
|
|
|
|
if (!customMem.customAlloc && !customMem.customFree) customMem = defaultCustomMem;
|
|
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->zd = ZSTD_createDCtx_advanced(customMem);
|
|
if (zds->zd == NULL) { ZSTD_freeDStream(zds); return NULL; }
|
|
zds->stage = zdss_init;
|
|
zds->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT;
|
|
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->zd);
|
|
ZSTD_free(zds->inBuff, cMem);
|
|
ZSTD_free(zds->outBuff, cMem);
|
|
ZSTD_free(zds->dictContent, cMem);
|
|
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1)
|
|
if (zds->legacyContext)
|
|
ZSTD_freeLegacyStreamContext(zds->legacyContext, zds->previousLegacyVersion);
|
|
#endif
|
|
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_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize)
|
|
{
|
|
zds->stage = zdss_loadHeader;
|
|
zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
|
|
if ((dict != zds->dictSource) | (dictSize != zds->dictSize)) { /* new dictionary */
|
|
if (dictSize > zds->dictSize) {
|
|
ZSTD_free(zds->dictContent, zds->customMem);
|
|
zds->dictContent = ZSTD_malloc(dictSize, zds->customMem);
|
|
if (zds->dictContent == NULL) return ERROR(memory_allocation);
|
|
}
|
|
memcpy(zds->dictContent, dict, dictSize);
|
|
zds->dictSize = dictSize;
|
|
}
|
|
zds->legacyVersion = 0;
|
|
return ZSTD_frameHeaderSize_prefix;
|
|
}
|
|
|
|
size_t ZSTD_initDStream(ZSTD_DStream* zds)
|
|
{
|
|
return ZSTD_initDStream_usingDict(zds, NULL, 0);
|
|
}
|
|
|
|
size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds,
|
|
ZSTD_DStreamParameter_e paramType, unsigned paramValue)
|
|
{
|
|
switch(paramType)
|
|
{
|
|
default : return ERROR(parameter_unknown);
|
|
case ZSTDdsp_maxWindowSize : zds->maxWindowSize = paramValue; break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds)
|
|
{
|
|
return sizeof(*zds) + ZSTD_sizeof_DCtx(zds->zd) + zds->inBuffSize + zds->outBuffSize;
|
|
}
|
|
|
|
|
|
/* *** Decompression *** */
|
|
|
|
MEM_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;
|
|
|
|
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
|
|
if (zds->legacyVersion)
|
|
return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);
|
|
#endif
|
|
|
|
while (someMoreWork) {
|
|
switch(zds->stage)
|
|
{
|
|
case zdss_init :
|
|
return ERROR(init_missing);
|
|
|
|
case zdss_loadHeader :
|
|
{ size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize);
|
|
if (ZSTD_isError(hSize))
|
|
#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1)
|
|
{ U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart);
|
|
if (legacyVersion) {
|
|
size_t initResult;
|
|
initResult = ZSTD_initLegacyStream(&zds->legacyContext, zds->previousLegacyVersion, legacyVersion,
|
|
zds->dictContent, zds->dictSize);
|
|
if (ZSTD_isError(initResult)) return initResult;
|
|
zds->legacyVersion = zds->previousLegacyVersion = legacyVersion;
|
|
return ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input);
|
|
} else {
|
|
return hSize; /* error */
|
|
} }
|
|
#else
|
|
return hSize;
|
|
#endif
|
|
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;
|
|
} }
|
|
|
|
/* Consume header */
|
|
ZSTD_decompressBegin_usingDict(zds->zd, zds->dictContent, zds->dictSize);
|
|
{ size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->zd); /* == ZSTD_frameHeaderSize_prefix */
|
|
size_t const h1Result = ZSTD_decompressContinue(zds->zd, NULL, 0, zds->headerBuffer, h1Size);
|
|
if (ZSTD_isError(h1Result)) return h1Result; /* should not happen : already checked */
|
|
{ size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->zd);
|
|
size_t const h2Result = ZSTD_decompressContinue(zds->zd, NULL, 0, zds->headerBuffer+h1Size, h2Size);
|
|
if (ZSTD_isError(h2Result)) return h2Result;
|
|
} }
|
|
|
|
zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN);
|
|
if (zds->fParams.windowSize > zds->maxWindowSize) return ERROR(frameParameter_unsupported);
|
|
|
|
/* Frame header instruct buffer sizes */
|
|
{ size_t const blockSize = MIN(zds->fParams.windowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX);
|
|
size_t const neededOutSize = zds->fParams.windowSize + blockSize;
|
|
zds->blockSize = blockSize;
|
|
if (zds->inBuffSize < blockSize) {
|
|
ZSTD_free(zds->inBuff, zds->customMem);
|
|
zds->inBuffSize = blockSize;
|
|
zds->inBuff = (char*)ZSTD_malloc(blockSize, zds->customMem);
|
|
if (zds->inBuff == NULL) return ERROR(memory_allocation);
|
|
}
|
|
if (zds->outBuffSize < neededOutSize) {
|
|
ZSTD_free(zds->outBuff, zds->customMem);
|
|
zds->outBuffSize = neededOutSize;
|
|
zds->outBuff = (char*)ZSTD_malloc(neededOutSize, zds->customMem);
|
|
if (zds->outBuff == NULL) return ERROR(memory_allocation);
|
|
} }
|
|
zds->stage = zdss_read;
|
|
/* pass-through */
|
|
|
|
case zdss_read:
|
|
{ size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->zd);
|
|
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->zd);
|
|
size_t const decodedSize = ZSTD_decompressContinue(zds->zd,
|
|
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->zd);
|
|
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->zd);
|
|
size_t const decodedSize = ZSTD_decompressContinue(zds->zd,
|
|
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 flush everything */
|
|
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->zd);
|
|
if (!nextSrcSizeHint) return (zds->outEnd != zds->outStart); /* return 0 only if fully flushed too */
|
|
nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->zd) == ZSTDnit_block);
|
|
if (zds->inPos > nextSrcSizeHint) return ERROR(GENERIC); /* should never happen */
|
|
nextSrcSizeHint -= zds->inPos; /* already loaded*/
|
|
return nextSrcSizeHint;
|
|
}
|
|
}
|