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Diffstat (limited to 'lib/zstd/decompress.c')
| -rw-r--r-- | lib/zstd/decompress.c | 2531 |
1 files changed, 0 insertions, 2531 deletions
diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c deleted file mode 100644 index 66cd487a326a..000000000000 --- a/lib/zstd/decompress.c +++ /dev/null @@ -1,2531 +0,0 @@ -/** - * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. - * All rights reserved. - * - * This source code is licensed under the BSD-style license found in the - * LICENSE file in the root directory of https://github.com/facebook/zstd. - * An additional grant of patent rights can be found in the PATENTS file in the - * same directory. - * - * This program is free software; you can redistribute it and/or modify it under - * the terms of the GNU General Public License version 2 as published by the - * Free Software Foundation. This program is dual-licensed; you may select - * either version 2 of the GNU General Public License ("GPL") or BSD license - * ("BSD"). - */ - -/* *************************************************************** -* Tuning parameters -*****************************************************************/ -/*! -* MAXWINDOWSIZE_DEFAULT : -* maximum window size accepted by DStream, by default. -* Frames requiring more memory will be rejected. -*/ -#ifndef ZSTD_MAXWINDOWSIZE_DEFAULT -#define ZSTD_MAXWINDOWSIZE_DEFAULT ((1 << ZSTD_WINDOWLOG_MAX) + 1) /* defined within zstd.h */ -#endif - -/*-******************************************************* -* Dependencies -*********************************************************/ -#include "fse.h" -#include "huf.h" -#include "mem.h" /* low level memory routines */ -#include "zstd_internal.h" -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/string.h> /* memcpy, memmove, memset */ - -#define ZSTD_PREFETCH(ptr) __builtin_prefetch(ptr, 0, 0) - -/*-************************************* -* Macros -***************************************/ -#define ZSTD_isError ERR_isError /* for inlining */ -#define FSE_isError ERR_isError -#define HUF_isError ERR_isError - -/*_******************************************************* -* Memory operations -**********************************************************/ -static void ZSTD_copy4(void *dst, const void *src) { memcpy(dst, src, 4); } - -/*-************************************************************* -* Context management -***************************************************************/ -typedef enum { - ZSTDds_getFrameHeaderSize, - ZSTDds_decodeFrameHeader, - ZSTDds_decodeBlockHeader, - ZSTDds_decompressBlock, - ZSTDds_decompressLastBlock, - ZSTDds_checkChecksum, - ZSTDds_decodeSkippableHeader, - ZSTDds_skipFrame -} ZSTD_dStage; - -typedef struct { - FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)]; - FSE_DTable OFTable[FSE_DTABLE_SIZE_U32(OffFSELog)]; - FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)]; - HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */ - U64 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32 / 2]; - U32 rep[ZSTD_REP_NUM]; -} ZSTD_entropyTables_t; - -struct ZSTD_DCtx_s { - const FSE_DTable *LLTptr; - const FSE_DTable *MLTptr; - const FSE_DTable *OFTptr; - const HUF_DTable *HUFptr; - ZSTD_entropyTables_t entropy; - const void *previousDstEnd; /* detect continuity */ - const void *base; /* start of curr segment */ - const void *vBase; /* virtual start of previous segment if it was just before curr one */ - const void *dictEnd; /* end of previous segment */ - size_t expected; - ZSTD_frameParams fParams; - blockType_e bType; /* used in ZSTD_decompressContinue(), to transfer blockType between header decoding and block decoding stages */ - ZSTD_dStage stage; - U32 litEntropy; - U32 fseEntropy; - struct xxh64_state xxhState; - size_t headerSize; - U32 dictID; - const BYTE *litPtr; - ZSTD_customMem customMem; - size_t litSize; - size_t rleSize; - BYTE litBuffer[ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH]; - BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; -}; /* typedef'd to ZSTD_DCtx within "zstd.h" */ - -size_t ZSTD_DCtxWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DCtx)); } - -size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx) -{ - dctx->expected = ZSTD_frameHeaderSize_prefix; - dctx->stage = ZSTDds_getFrameHeaderSize; - dctx->previousDstEnd = NULL; - dctx->base = NULL; - dctx->vBase = NULL; - dctx->dictEnd = NULL; - dctx->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ - dctx->litEntropy = dctx->fseEntropy = 0; - dctx->dictID = 0; - ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.rep) == sizeof(repStartValue)); - memcpy(dctx->entropy.rep, repStartValue, sizeof(repStartValue)); /* initial repcodes */ - dctx->LLTptr = dctx->entropy.LLTable; - dctx->MLTptr = dctx->entropy.MLTable; - dctx->OFTptr = dctx->entropy.OFTable; - dctx->HUFptr = dctx->entropy.hufTable; - return 0; -} - -ZSTD_DCtx *ZSTD_createDCtx_advanced(ZSTD_customMem customMem) -{ - ZSTD_DCtx *dctx; - - if (!customMem.customAlloc || !customMem.customFree) - return NULL; - - dctx = (ZSTD_DCtx *)ZSTD_malloc(sizeof(ZSTD_DCtx), customMem); - if (!dctx) - return NULL; - memcpy(&dctx->customMem, &customMem, sizeof(customMem)); - ZSTD_decompressBegin(dctx); - return dctx; -} - -ZSTD_DCtx *ZSTD_initDCtx(void *workspace, size_t workspaceSize) -{ - ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); - return ZSTD_createDCtx_advanced(stackMem); -} - -size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx) -{ - if (dctx == NULL) - return 0; /* support free on NULL */ - ZSTD_free(dctx, dctx->customMem); - return 0; /* reserved as a potential error code in the future */ -} - -void ZSTD_copyDCtx(ZSTD_DCtx *dstDCtx, const ZSTD_DCtx *srcDCtx) -{ - size_t const workSpaceSize = (ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH) + ZSTD_frameHeaderSize_max; - memcpy(dstDCtx, srcDCtx, sizeof(ZSTD_DCtx) - workSpaceSize); /* no need to copy workspace */ -} - -static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict); - -/*-************************************************************* -* Decompression section -***************************************************************/ - -/*! ZSTD_isFrame() : - * Tells if the content of `buffer` starts with a valid Frame Identifier. - * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0. - * Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled. - * Note 3 : Skippable Frame Identifiers are considered valid. */ -unsigned ZSTD_isFrame(const void *buffer, size_t size) -{ - if (size < 4) - return 0; - { - U32 const magic = ZSTD_readLE32(buffer); - if (magic == ZSTD_MAGICNUMBER) - return 1; - if ((magic & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) - return 1; - } - return 0; -} - -/** ZSTD_frameHeaderSize() : -* srcSize must be >= ZSTD_frameHeaderSize_prefix. -* @return : size of the Frame Header */ -static size_t ZSTD_frameHeaderSize(const void *src, size_t srcSize) -{ - if (srcSize < ZSTD_frameHeaderSize_prefix) - return ERROR(srcSize_wrong); - { - BYTE const fhd = ((const BYTE *)src)[4]; - U32 const dictID = fhd & 3; - U32 const singleSegment = (fhd >> 5) & 1; - U32 const fcsId = fhd >> 6; - return ZSTD_frameHeaderSize_prefix + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId] + (singleSegment && !fcsId); - } -} - -/** ZSTD_getFrameParams() : -* decode Frame Header, or require larger `srcSize`. -* @return : 0, `fparamsPtr` is correctly filled, -* >0, `srcSize` is too small, result is expected `srcSize`, -* or an error code, which can be tested using ZSTD_isError() */ -size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src, size_t srcSize) -{ - const BYTE *ip = (const BYTE *)src; - - if (srcSize < ZSTD_frameHeaderSize_prefix) - return ZSTD_frameHeaderSize_prefix; - if (ZSTD_readLE32(src) != ZSTD_MAGICNUMBER) { - if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { - if (srcSize < ZSTD_skippableHeaderSize) - return ZSTD_skippableHeaderSize; /* magic number + skippable frame length */ - memset(fparamsPtr, 0, sizeof(*fparamsPtr)); - fparamsPtr->frameContentSize = ZSTD_readLE32((const char *)src + 4); - fparamsPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */ - return 0; - } - return ERROR(prefix_unknown); - } - - /* ensure there is enough `srcSize` to fully read/decode frame header */ - { - size_t const fhsize = ZSTD_frameHeaderSize(src, srcSize); - if (srcSize < fhsize) - return fhsize; - } - - { - BYTE const fhdByte = ip[4]; - size_t pos = 5; - U32 const dictIDSizeCode = fhdByte & 3; - U32 const checksumFlag = (fhdByte >> 2) & 1; - U32 const singleSegment = (fhdByte >> 5) & 1; - U32 const fcsID = fhdByte >> 6; - U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX; - U32 windowSize = 0; - U32 dictID = 0; - U64 frameContentSize = 0; - if ((fhdByte & 0x08) != 0) - return ERROR(frameParameter_unsupported); /* reserved bits, which must be zero */ - if (!singleSegment) { - BYTE const wlByte = ip[pos++]; - U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN; - if (windowLog > ZSTD_WINDOWLOG_MAX) - return ERROR(frameParameter_windowTooLarge); /* avoids issue with 1 << windowLog */ - windowSize = (1U << windowLog); - windowSize += (windowSize >> 3) * (wlByte & 7); - } - - switch (dictIDSizeCode) { - default: /* impossible */ - case 0: break; - case 1: - dictID = ip[pos]; - pos++; - break; - case 2: - dictID = ZSTD_readLE16(ip + pos); - pos += 2; - break; - case 3: - dictID = ZSTD_readLE32(ip + pos); - pos += 4; - break; - } - switch (fcsID) { - default: /* impossible */ - case 0: - if (singleSegment) - frameContentSize = ip[pos]; - break; - case 1: frameContentSize = ZSTD_readLE16(ip + pos) + 256; break; - case 2: frameContentSize = ZSTD_readLE32(ip + pos); break; - case 3: frameContentSize = ZSTD_readLE64(ip + pos); break; - } - if (!windowSize) - windowSize = (U32)frameContentSize; - if (windowSize > windowSizeMax) - return ERROR(frameParameter_windowTooLarge); - fparamsPtr->frameContentSize = frameContentSize; - fparamsPtr->windowSize = windowSize; - fparamsPtr->dictID = dictID; - fparamsPtr->checksumFlag = checksumFlag; - } - return 0; -} - -/** ZSTD_getFrameContentSize() : -* compatible with legacy mode -* @return : decompressed size of the single frame pointed to be `src` if known, otherwise -* - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined -* - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) */ -unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize) -{ - { - ZSTD_frameParams fParams; - if (ZSTD_getFrameParams(&fParams, src, srcSize) != 0) - return ZSTD_CONTENTSIZE_ERROR; - if (fParams.windowSize == 0) { - /* Either skippable or empty frame, size == 0 either way */ - return 0; - } else if (fParams.frameContentSize != 0) { - return fParams.frameContentSize; - } else { - return ZSTD_CONTENTSIZE_UNKNOWN; - } - } -} - -/** ZSTD_findDecompressedSize() : - * compatible with legacy mode - * `srcSize` must be the exact length of some number of ZSTD compressed and/or - * skippable frames - * @return : decompressed size of the frames contained */ -unsigned long long ZSTD_findDecompressedSize(const void *src, size_t srcSize) -{ - { - unsigned long long totalDstSize = 0; - while (srcSize >= ZSTD_frameHeaderSize_prefix) { - const U32 magicNumber = ZSTD_readLE32(src); - - if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { - size_t skippableSize; - if (srcSize < ZSTD_skippableHeaderSize) - return ERROR(srcSize_wrong); - skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize; - if (srcSize < skippableSize) { - return ZSTD_CONTENTSIZE_ERROR; - } - - src = (const BYTE *)src + skippableSize; - srcSize -= skippableSize; - continue; - } - - { - unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize); - if (ret >= ZSTD_CONTENTSIZE_ERROR) - return ret; - - /* check for overflow */ - if (totalDstSize + ret < totalDstSize) - return ZSTD_CONTENTSIZE_ERROR; - totalDstSize += ret; - } - { - size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize); - if (ZSTD_isError(frameSrcSize)) { - return ZSTD_CONTENTSIZE_ERROR; - } - - src = (const BYTE *)src + frameSrcSize; - srcSize -= frameSrcSize; - } - } - - if (srcSize) { - return ZSTD_CONTENTSIZE_ERROR; - } - - return totalDstSize; - } -} - -/** ZSTD_decodeFrameHeader() : -* `headerSize` must be the size provided by ZSTD_frameHeaderSize(). -* @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */ -static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx *dctx, const void *src, size_t headerSize) -{ - size_t const result = ZSTD_getFrameParams(&(dctx->fParams), src, headerSize); - if (ZSTD_isError(result)) - return result; /* invalid header */ - if (result > 0) - return ERROR(srcSize_wrong); /* headerSize too small */ - if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID)) - return ERROR(dictionary_wrong); - if (dctx->fParams.checksumFlag) - xxh64_reset(&dctx->xxhState, 0); - return 0; -} - -typedef struct { - blockType_e blockType; - U32 lastBlock; - U32 origSize; -} blockProperties_t; - -/*! ZSTD_getcBlockSize() : -* Provides the size of compressed block from block header `src` */ -size_t ZSTD_getcBlockSize(const void *src, size_t srcSize, blockProperties_t *bpPtr) -{ - if (srcSize < ZSTD_blockHeaderSize) - return ERROR(srcSize_wrong); - { - U32 const cBlockHeader = ZSTD_readLE24(src); - U32 const cSize = cBlockHeader >> 3; - bpPtr->lastBlock = cBlockHeader & 1; - bpPtr->blockType = (blockType_e)((cBlockHeader >> 1) & 3); - bpPtr->origSize = cSize; /* only useful for RLE */ - if (bpPtr->blockType == bt_rle) - return 1; - if (bpPtr->blockType == bt_reserved) - return ERROR(corruption_detected); - return cSize; - } -} - -static size_t ZSTD_copyRawBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize) -{ - if (srcSize > dstCapacity) - return ERROR(dstSize_tooSmall); - memcpy(dst, src, srcSize); - return srcSize; -} - -static size_t ZSTD_setRleBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize, size_t regenSize) -{ - if (srcSize != 1) - return ERROR(srcSize_wrong); - if (regenSize > dstCapacity) - return ERROR(dstSize_tooSmall); - memset(dst, *(const BYTE *)src, regenSize); - return regenSize; -} - -/*! ZSTD_decodeLiteralsBlock() : - @return : nb of bytes read from src (< srcSize ) */ -size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx *dctx, const void *src, size_t srcSize) /* note : srcSize < BLOCKSIZE */ -{ - if (srcSize < MIN_CBLOCK_SIZE) - return ERROR(corruption_detected); - - { - const BYTE *const istart = (const BYTE *)src; - symbolEncodingType_e const litEncType = (symbolEncodingType_e)(istart[0] & 3); - - switch (litEncType) { - case set_repeat: - if (dctx->litEntropy == 0) - return ERROR(dictionary_corrupted); - fallthrough; - case set_compressed: - if (srcSize < 5) - return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3 */ - { - size_t lhSize, litSize, litCSize; - U32 singleStream = 0; - U32 const lhlCode = (istart[0] >> 2) & 3; - U32 const lhc = ZSTD_readLE32(istart); - switch (lhlCode) { - case 0: - case 1: - default: /* note : default is impossible, since lhlCode into [0..3] */ - /* 2 - 2 - 10 - 10 */ - singleStream = !lhlCode; - lhSize = 3; - litSize = (lhc >> 4) & 0x3FF; - litCSize = (lhc >> 14) & 0x3FF; - break; - case 2: - /* 2 - 2 - 14 - 14 */ - lhSize = 4; - litSize = (lhc >> 4) & 0x3FFF; - litCSize = lhc >> 18; - break; - case 3: - /* 2 - 2 - 18 - 18 */ - lhSize = 5; - litSize = (lhc >> 4) & 0x3FFFF; - litCSize = (lhc >> 22) + (istart[4] << 10); - break; - } - if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) - return ERROR(corruption_detected); - if (litCSize + lhSize > srcSize) - return ERROR(corruption_detected); - - if (HUF_isError( - (litEncType == set_repeat) - ? (singleStream ? HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr) - : HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr)) - : (singleStream - ? HUF_decompress1X2_DCtx_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize, - dctx->entropy.workspace, sizeof(dctx->entropy.workspace)) - : HUF_decompress4X_hufOnly_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize, - dctx->entropy.workspace, sizeof(dctx->entropy.workspace))))) - return ERROR(corruption_detected); - - dctx->litPtr = dctx->litBuffer; - dctx->litSize = litSize; - dctx->litEntropy = 1; - if (litEncType == set_compressed) - dctx->HUFptr = dctx->entropy.hufTable; - memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); - return litCSize + lhSize; - } - - case set_basic: { - size_t litSize, lhSize; - U32 const lhlCode = ((istart[0]) >> 2) & 3; - switch (lhlCode) { - case 0: - case 2: - default: /* note : default is impossible, since lhlCode into [0..3] */ - lhSize = 1; - litSize = istart[0] >> 3; - break; - case 1: - lhSize = 2; - litSize = ZSTD_readLE16(istart) >> 4; - break; - case 3: - lhSize = 3; - litSize = ZSTD_readLE24(istart) >> 4; - break; - } - - if (lhSize + litSize + WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */ - if (litSize + lhSize > srcSize) - return ERROR(corruption_detected); - memcpy(dctx->litBuffer, istart + lhSize, litSize); - dctx->litPtr = dctx->litBuffer; - dctx->litSize = litSize; - memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); - return lhSize + litSize; - } - /* direct reference into compressed stream */ - dctx->litPtr = istart + lhSize; - dctx->litSize = litSize; - return lhSize + litSize; - } - - case set_rle: { - U32 const lhlCode = ((istart[0]) >> 2) & 3; - size_t litSize, lhSize; - switch (lhlCode) { - case 0: - case 2: - default: /* note : default is impossible, since lhlCode into [0..3] */ - lhSize = 1; - litSize = istart[0] >> 3; - break; - case 1: - lhSize = 2; - litSize = ZSTD_readLE16(istart) >> 4; - break; - case 3: - lhSize = 3; - litSize = ZSTD_readLE24(istart) >> 4; - if (srcSize < 4) - return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */ - break; - } - if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) - return ERROR(corruption_detected); - memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH); - dctx->litPtr = dctx->litBuffer; - dctx->litSize = litSize; - return lhSize + 1; - } - default: - return ERROR(corruption_detected); /* impossible */ - } - } -} - -typedef union { - FSE_decode_t realData; - U32 alignedBy4; -} FSE_decode_t4; - -static const FSE_decode_t4 LL_defaultDTable[(1 << LL_DEFAULTNORMLOG) + 1] = { - {{LL_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ - {{0, 0, 4}}, /* 0 : base, symbol, bits */ - {{16, 0, 4}}, - {{32, 1, 5}}, - {{0, 3, 5}}, - {{0, 4, 5}}, - {{0, 6, 5}}, - {{0, 7, 5}}, - {{0, 9, 5}}, - {{0, 10, 5}}, - {{0, 12, 5}}, - {{0, 14, 6}}, - {{0, 16, 5}}, - {{0, 18, 5}}, - {{0, 19, 5}}, - {{0, 21, 5}}, - {{0, 22, 5}}, - {{0, 24, 5}}, - {{32, 25, 5}}, - {{0, 26, 5}}, - {{0, 27, 6}}, - {{0, 29, 6}}, - {{0, 31, 6}}, - {{32, 0, 4}}, - {{0, 1, 4}}, - {{0, 2, 5}}, - {{32, 4, 5}}, - {{0, 5, 5}}, - {{32, 7, 5}}, - {{0, 8, 5}}, - {{32, 10, 5}}, - {{0, 11, 5}}, - {{0, 13, 6}}, - {{32, 16, 5}}, - {{0, 17, 5}}, - {{32, 19, 5}}, - {{0, 20, 5}}, - {{32, 22, 5}}, - {{0, 23, 5}}, - {{0, 25, 4}}, - {{16, 25, 4}}, - {{32, 26, 5}}, - {{0, 28, 6}}, - {{0, 30, 6}}, - {{48, 0, 4}}, - {{16, 1, 4}}, - {{32, 2, 5}}, - {{32, 3, 5}}, - {{32, 5, 5}}, - {{32, 6, 5}}, - {{32, 8, 5}}, - {{32, 9, 5}}, - {{32, 11, 5}}, - {{32, 12, 5}}, - {{0, 15, 6}}, - {{32, 17, 5}}, - {{32, 18, 5}}, - {{32, 20, 5}}, - {{32, 21, 5}}, - {{32, 23, 5}}, - {{32, 24, 5}}, - {{0, 35, 6}}, - {{0, 34, 6}}, - {{0, 33, 6}}, - {{0, 32, 6}}, -}; /* LL_defaultDTable */ - -static const FSE_decode_t4 ML_defaultDTable[(1 << ML_DEFAULTNORMLOG) + 1] = { - {{ML_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ - {{0, 0, 6}}, /* 0 : base, symbol, bits */ - {{0, 1, 4}}, - {{32, 2, 5}}, - {{0, 3, 5}}, - {{0, 5, 5}}, - {{0, 6, 5}}, - {{0, 8, 5}}, - {{0, 10, 6}}, - {{0, 13, 6}}, - {{0, 16, 6}}, - {{0, 19, 6}}, - {{0, 22, 6}}, - {{0, 25, 6}}, - {{0, 28, 6}}, - {{0, 31, 6}}, - {{0, 33, 6}}, - {{0, 35, 6}}, - {{0, 37, 6}}, - {{0, 39, 6}}, - {{0, 41, 6}}, - {{0, 43, 6}}, - {{0, 45, 6}}, - {{16, 1, 4}}, - {{0, 2, 4}}, - {{32, 3, 5}}, - {{0, 4, 5}}, - {{32, 6, 5}}, - {{0, 7, 5}}, - {{0, 9, 6}}, - {{0, 12, 6}}, - {{0, 15, 6}}, - {{0, 18, 6}}, - {{0, 21, 6}}, - {{0, 24, 6}}, - {{0, 27, 6}}, - {{0, 30, 6}}, - {{0, 32, 6}}, - {{0, 34, 6}}, - {{0, 36, 6}}, - {{0, 38, 6}}, - {{0, 40, 6}}, - {{0, 42, 6}}, - {{0, 44, 6}}, - {{32, 1, 4}}, - {{48, 1, 4}}, - {{16, 2, 4}}, - {{32, 4, 5}}, - {{32, 5, 5}}, - {{32, 7, 5}}, - {{32, 8, 5}}, - {{0, 11, 6}}, - {{0, 14, 6}}, - {{0, 17, 6}}, - {{0, 20, 6}}, - {{0, 23, 6}}, - {{0, 26, 6}}, - {{0, 29, 6}}, - {{0, 52, 6}}, - {{0, 51, 6}}, - {{0, 50, 6}}, - {{0, 49, 6}}, - {{0, 48, 6}}, - {{0, 47, 6}}, - {{0, 46, 6}}, -}; /* ML_defaultDTable */ - -static const FSE_decode_t4 OF_defaultDTable[(1 << OF_DEFAULTNORMLOG) + 1] = { - {{OF_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ - {{0, 0, 5}}, /* 0 : base, symbol, bits */ - {{0, 6, 4}}, - {{0, 9, 5}}, - {{0, 15, 5}}, - {{0, 21, 5}}, - {{0, 3, 5}}, - {{0, 7, 4}}, - {{0, 12, 5}}, - {{0, 18, 5}}, - {{0, 23, 5}}, - {{0, 5, 5}}, - {{0, 8, 4}}, - {{0, 14, 5}}, - {{0, 20, 5}}, - {{0, 2, 5}}, - {{16, 7, 4}}, - {{0, 11, 5}}, - {{0, 17, 5}}, - {{0, 22, 5}}, - {{0, 4, 5}}, - {{16, 8, 4}}, - {{0, 13, 5}}, - {{0, 19, 5}}, - {{0, 1, 5}}, - {{16, 6, 4}}, - {{0, 10, 5}}, - {{0, 16, 5}}, - {{0, 28, 5}}, - {{0, 27, 5}}, - {{0, 26, 5}}, - {{0, 25, 5}}, - {{0, 24, 5}}, -}; /* OF_defaultDTable */ - -/*! ZSTD_buildSeqTable() : - @return : nb bytes read from src, - or an error code if it fails, testable with ZSTD_isError() -*/ -static size_t ZSTD_buildSeqTable(FSE_DTable *DTableSpace, const FSE_DTable **DTablePtr, symbolEncodingType_e type, U32 max, U32 maxLog, const void *src, - size_t srcSize, const FSE_decode_t4 *defaultTable, U32 flagRepeatTable, void *workspace, size_t workspaceSize) -{ - const void *const tmpPtr = defaultTable; /* bypass strict aliasing */ - switch (type) { - case set_rle: - if (!srcSize) - return ERROR(srcSize_wrong); - if ((*(const BYTE *)src) > max) - return ERROR(corruption_detected); - FSE_buildDTable_rle(DTableSpace, *(const BYTE *)src); - *DTablePtr = DTableSpace; - return 1; - case set_basic: *DTablePtr = (const FSE_DTable *)tmpPtr; return 0; - case set_repeat: - if (!flagRepeatTable) - return ERROR(corruption_detected); - return 0; - default: /* impossible */ - case set_compressed: { - U32 tableLog; - S16 *norm = (S16 *)workspace; - size_t const spaceUsed32 = ALIGN(sizeof(S16) * (MaxSeq + 1), sizeof(U32)) >> 2; - - if ((spaceUsed32 << 2) > workspaceSize) - return ERROR(GENERIC); - workspace = (U32 *)workspace + spaceUsed32; - workspaceSize -= (spaceUsed32 << 2); - { - size_t const headerSize = FSE_readNCount(norm, &max, &tableLog, src, srcSize); - if (FSE_isError(headerSize)) - return ERROR(corruption_detected); - if (tableLog > maxLog) - return ERROR(corruption_detected); - FSE_buildDTable_wksp(DTableSpace, norm, max, tableLog, workspace, workspaceSize); - *DTablePtr = DTableSpace; - return headerSize; - } - } - } -} - -size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx *dctx, int *nbSeqPtr, const void *src, size_t srcSize) -{ - const BYTE *const istart = (const BYTE *const)src; - const BYTE *const iend = istart + srcSize; - const BYTE *ip = istart; - - /* check */ - if (srcSize < MIN_SEQUENCES_SIZE) - return ERROR(srcSize_wrong); - - /* SeqHead */ - { - int nbSeq = *ip++; - if (!nbSeq) { - *nbSeqPtr = 0; - return 1; - } - if (nbSeq > 0x7F) { - if (nbSeq == 0xFF) { - if (ip + 2 > iend) - return ERROR(srcSize_wrong); - nbSeq = ZSTD_readLE16(ip) + LONGNBSEQ, ip += 2; - } else { - if (ip >= iend) - return ERROR(srcSize_wrong); - nbSeq = ((nbSeq - 0x80) << 8) + *ip++; - } - } - *nbSeqPtr = nbSeq; - } - - /* FSE table descriptors */ - if (ip + 4 > iend) - return ERROR(srcSize_wrong); /* minimum possible size */ - { - symbolEncodingType_e const LLtype = (symbolEncodingType_e)(*ip >> 6); - symbolEncodingType_e const OFtype = (symbolEncodingType_e)((*ip >> 4) & 3); - symbolEncodingType_e const MLtype = (symbolEncodingType_e)((*ip >> 2) & 3); - ip++; - - /* Build DTables */ - { - size_t const llhSize = ZSTD_buildSeqTable(dctx->entropy.LLTable, &dctx->LLTptr, LLtype, MaxLL, LLFSELog, ip, iend - ip, - LL_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); - if (ZSTD_isError(llhSize)) - return ERROR(corruption_detected); - ip += llhSize; - } - { - size_t const ofhSize = ZSTD_buildSeqTable(dctx->entropy.OFTable, &dctx->OFTptr, OFtype, MaxOff, OffFSELog, ip, iend - ip, - OF_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); - if (ZSTD_isError(ofhSize)) - return ERROR(corruption_detected); - ip += ofhSize; - } - { - size_t const mlhSize = ZSTD_buildSeqTable(dctx->entropy.MLTable, &dctx->MLTptr, MLtype, MaxML, MLFSELog, ip, iend - ip, - ML_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); - if (ZSTD_isError(mlhSize)) - return ERROR(corruption_detected); - ip += mlhSize; - } - } - - return ip - istart; -} - -typedef struct { - size_t litLength; - size_t matchLength; - size_t offset; - const BYTE *match; -} seq_t; - -typedef struct { - BIT_DStream_t DStream; - FSE_DState_t stateLL; - FSE_DState_t stateOffb; - FSE_DState_t stateML; - size_t prevOffset[ZSTD_REP_NUM]; - const BYTE *base; - size_t pos; - uPtrDiff gotoDict; -} seqState_t; - -FORCE_NOINLINE -size_t ZSTD_execSequenceLast7(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, - const BYTE *const vBase, const BYTE *const dictEnd) -{ - BYTE *const oLitEnd = op + sequence.litLength; - size_t const sequenceLength = sequence.litLength + sequence.matchLength; - BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ - BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; - const BYTE *const iLitEnd = *litPtr + sequence.litLength; - const BYTE *match = oLitEnd - sequence.offset; - - /* check */ - if (oMatchEnd > oend) - return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ - if (iLitEnd > litLimit) - return ERROR(corruption_detected); /* over-read beyond lit buffer */ - if (oLitEnd <= oend_w) - return ERROR(GENERIC); /* Precondition */ - - /* copy literals */ - if (op < oend_w) { - ZSTD_wildcopy(op, *litPtr, oend_w - op); - *litPtr += oend_w - op; - op = oend_w; - } - while (op < oLitEnd) - *op++ = *(*litPtr)++; - - /* copy Match */ - if (sequence.offset > (size_t)(oLitEnd - base)) { - /* offset beyond prefix */ - if (sequence.offset > (size_t)(oLitEnd - vBase)) - return ERROR(corruption_detected); - match = dictEnd - (base - match); - if (match + sequence.matchLength <= dictEnd) { - memmove(oLitEnd, match, sequence.matchLength); - return sequenceLength; - } - /* span extDict & currPrefixSegment */ - { - size_t const length1 = dictEnd - match; - memmove(oLitEnd, match, length1); - op = oLitEnd + length1; - sequence.matchLength -= length1; - match = base; - } - } - while (op < oMatchEnd) - *op++ = *match++; - return sequenceLength; -} - -static seq_t ZSTD_decodeSequence(seqState_t *seqState) -{ - seq_t seq; - - U32 const llCode = FSE_peekSymbol(&seqState->stateLL); - U32 const mlCode = FSE_peekSymbol(&seqState->stateML); - U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ - - U32 const llBits = LL_bits[llCode]; - U32 const mlBits = ML_bits[mlCode]; - U32 const ofBits = ofCode; - U32 const totalBits = llBits + mlBits + ofBits; - - static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, - 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000}; - - static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, - 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41, - 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003}; - - static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD, - 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, - 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD}; - - /* sequence */ - { - size_t offset; - if (!ofCode) - offset = 0; - else { - offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ - if (ZSTD_32bits()) - BIT_reloadDStream(&seqState->DStream); - } - - if (ofCode <= 1) { - offset += (llCode == 0); - if (offset) { - size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; - temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ - if (offset != 1) - seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset = temp; - } else { - offset = seqState->prevOffset[0]; - } - } else { - seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset; - } - seq.offset = offset; - } - - seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ - if (ZSTD_32bits() && (mlBits + llBits > 24)) - BIT_reloadDStream(&seqState->DStream); - - seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ - if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) - BIT_reloadDStream(&seqState->DStream); - - /* ANS state update */ - FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ - FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ - if (ZSTD_32bits()) - BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ - FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ - - seq.match = NULL; - - return seq; -} - -FORCE_INLINE -size_t ZSTD_execSequence(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, - const BYTE *const vBase, const BYTE *const dictEnd) -{ - BYTE *const oLitEnd = op + sequence.litLength; - size_t const sequenceLength = sequence.litLength + sequence.matchLength; - BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ - BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; - const BYTE *const iLitEnd = *litPtr + sequence.litLength; - const BYTE *match = oLitEnd - sequence.offset; - - /* check */ - if (oMatchEnd > oend) - return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ - if (iLitEnd > litLimit) - return ERROR(corruption_detected); /* over-read beyond lit buffer */ - if (oLitEnd > oend_w) - return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); - - /* copy Literals */ - ZSTD_copy8(op, *litPtr); - if (sequence.litLength > 8) - ZSTD_wildcopy(op + 8, (*litPtr) + 8, - sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ - op = oLitEnd; - *litPtr = iLitEnd; /* update for next sequence */ - - /* copy Match */ - if (sequence.offset > (size_t)(oLitEnd - base)) { - /* offset beyond prefix */ - if (sequence.offset > (size_t)(oLitEnd - vBase)) - return ERROR(corruption_detected); - match = dictEnd + (match - base); - if (match + sequence.matchLength <= dictEnd) { - memmove(oLitEnd, match, sequence.matchLength); - return sequenceLength; - } - /* span extDict & currPrefixSegment */ - { - size_t const length1 = dictEnd - match; - memmove(oLitEnd, match, length1); - op = oLitEnd + length1; - sequence.matchLength -= length1; - match = base; - if (op > oend_w || sequence.matchLength < MINMATCH) { - U32 i; - for (i = 0; i < sequence.matchLength; ++i) - op[i] = match[i]; - return sequenceLength; - } - } - } - /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */ - - /* match within prefix */ - if (sequence.offset < 8) { - /* close range match, overlap */ - static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ - static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */ - int const sub2 = dec64table[sequence.offset]; - op[0] = match[0]; - op[1] = match[1]; - op[2] = match[2]; - op[3] = match[3]; - match += dec32table[sequence.offset]; - ZSTD_copy4(op + 4, match); - match -= sub2; - } else { - ZSTD_copy8(op, match); - } - op += 8; - match += 8; - - if (oMatchEnd > oend - (16 - MINMATCH)) { - if (op < oend_w) { - ZSTD_wildcopy(op, match, oend_w - op); - match += oend_w - op; - op = oend_w; - } - while (op < oMatchEnd) - *op++ = *match++; - } else { - ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */ - } - return sequenceLength; -} - -static size_t ZSTD_decompressSequences(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize) -{ - const BYTE *ip = (const BYTE *)seqStart; - const BYTE *const iend = ip + seqSize; - BYTE *const ostart = (BYTE * const)dst; - BYTE *const oend = ostart + maxDstSize; - BYTE *op = ostart; - const BYTE *litPtr = dctx->litPtr; - const BYTE *const litEnd = litPtr + dctx->litSize; - const BYTE *const base = (const BYTE *)(dctx->base); - const BYTE *const vBase = (const BYTE *)(dctx->vBase); - const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd); - int nbSeq; - - /* Build Decoding Tables */ - { - size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); - if (ZSTD_isError(seqHSize)) - return seqHSize; - ip += seqHSize; - } - - /* Regen sequences */ - if (nbSeq) { - seqState_t seqState; - dctx->fseEntropy = 1; - { - U32 i; - for (i = 0; i < ZSTD_REP_NUM; i++) - seqState.prevOffset[i] = dctx->entropy.rep[i]; - } - CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected); - FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); - FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); - FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); - - for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq;) { - nbSeq--; - { - seq_t const sequence = ZSTD_decodeSequence(&seqState); - size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd); - if (ZSTD_isError(oneSeqSize)) - return oneSeqSize; - op += oneSeqSize; - } - } - - /* check if reached exact end */ - if (nbSeq) - return ERROR(corruption_detected); - /* save reps for next block */ - { - U32 i; - for (i = 0; i < ZSTD_REP_NUM; i++) - dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); - } - } - - /* last literal segment */ - { - size_t const lastLLSize = litEnd - litPtr; - if (lastLLSize > (size_t)(oend - op)) - return ERROR(dstSize_tooSmall); - memcpy(op, litPtr, lastLLSize); - op += lastLLSize; - } - - return op - ostart; -} - -FORCE_INLINE seq_t ZSTD_decodeSequenceLong_generic(seqState_t *seqState, int const longOffsets) -{ - seq_t seq; - - U32 const llCode = FSE_peekSymbol(&seqState->stateLL); - U32 const mlCode = FSE_peekSymbol(&seqState->stateML); - U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ - - U32 const llBits = LL_bits[llCode]; - U32 const mlBits = ML_bits[mlCode]; - U32 const ofBits = ofCode; - U32 const totalBits = llBits + mlBits + ofBits; - - static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, - 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000}; - - static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, - 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41, - 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003}; - - static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD, - 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, - 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD}; - - /* sequence */ - { - size_t offset; - if (!ofCode) - offset = 0; - else { - if (longOffsets) { - int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN); - offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits); - if (ZSTD_32bits() || extraBits) - BIT_reloadDStream(&seqState->DStream); - if (extraBits) - offset += BIT_readBitsFast(&seqState->DStream, extraBits); - } else { - offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ - if (ZSTD_32bits()) - BIT_reloadDStream(&seqState->DStream); - } - } - - if (ofCode <= 1) { - offset += (llCode == 0); - if (offset) { - size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; - temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ - if (offset != 1) - seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset = temp; - } else { - offset = seqState->prevOffset[0]; - } - } else { - seqState->prevOffset[2] = seqState->prevOffset[1]; - seqState->prevOffset[1] = seqState->prevOffset[0]; - seqState->prevOffset[0] = offset; - } - seq.offset = offset; - } - - seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ - if (ZSTD_32bits() && (mlBits + llBits > 24)) - BIT_reloadDStream(&seqState->DStream); - - seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ - if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) - BIT_reloadDStream(&seqState->DStream); - - { - size_t const pos = seqState->pos + seq.litLength; - seq.match = seqState->base + pos - seq.offset; /* single memory segment */ - if (seq.offset > pos) - seq.match += seqState->gotoDict; /* separate memory segment */ - seqState->pos = pos + seq.matchLength; - } - - /* ANS state update */ - FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ - FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ - if (ZSTD_32bits()) - BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ - FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ - - return seq; -} - -static seq_t ZSTD_decodeSequenceLong(seqState_t *seqState, unsigned const windowSize) -{ - if (ZSTD_highbit32(windowSize) > STREAM_ACCUMULATOR_MIN) { - return ZSTD_decodeSequenceLong_generic(seqState, 1); - } else { - return ZSTD_decodeSequenceLong_generic(seqState, 0); - } -} - -FORCE_INLINE -size_t ZSTD_execSequenceLong(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, - const BYTE *const vBase, const BYTE *const dictEnd) -{ - BYTE *const oLitEnd = op + sequence.litLength; - size_t const sequenceLength = sequence.litLength + sequence.matchLength; - BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ - BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; - const BYTE *const iLitEnd = *litPtr + sequence.litLength; - const BYTE *match = sequence.match; - - /* check */ - if (oMatchEnd > oend) - return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ - if (iLitEnd > litLimit) - return ERROR(corruption_detected); /* over-read beyond lit buffer */ - if (oLitEnd > oend_w) - return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); - - /* copy Literals */ - ZSTD_copy8(op, *litPtr); - if (sequence.litLength > 8) - ZSTD_wildcopy(op + 8, (*litPtr) + 8, - sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ - op = oLitEnd; - *litPtr = iLitEnd; /* update for next sequence */ - - /* copy Match */ - if (sequence.offset > (size_t)(oLitEnd - base)) { - /* offset beyond prefix */ - if (sequence.offset > (size_t)(oLitEnd - vBase)) - return ERROR(corruption_detected); - if (match + sequence.matchLength <= dictEnd) { - memmove(oLitEnd, match, sequence.matchLength); - return sequenceLength; - } - /* span extDict & currPrefixSegment */ - { - size_t const length1 = dictEnd - match; - memmove(oLitEnd, match, length1); - op = oLitEnd + length1; - sequence.matchLength -= length1; - match = base; - if (op > oend_w || sequence.matchLength < MINMATCH) { - U32 i; - for (i = 0; i < sequence.matchLength; ++i) - op[i] = match[i]; - return sequenceLength; - } - } - } - /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */ - - /* match within prefix */ - if (sequence.offset < 8) { - /* close range match, overlap */ - static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ - static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */ - int const sub2 = dec64table[sequence.offset]; - op[0] = match[0]; - op[1] = match[1]; - op[2] = match[2]; - op[3] = match[3]; - match += dec32table[sequence.offset]; - ZSTD_copy4(op + 4, match); - match -= sub2; - } else { - ZSTD_copy8(op, match); - } - op += 8; - match += 8; - - if (oMatchEnd > oend - (16 - MINMATCH)) { - if (op < oend_w) { - ZSTD_wildcopy(op, match, oend_w - op); - match += oend_w - op; - op = oend_w; - } - while (op < oMatchEnd) - *op++ = *match++; - } else { - ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */ - } - return sequenceLength; -} - -static size_t ZSTD_decompressSequencesLong(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize) -{ - const BYTE *ip = (const BYTE *)seqStart; - const BYTE *const iend = ip + seqSize; - BYTE *const ostart = (BYTE * const)dst; - BYTE *const oend = ostart + maxDstSize; - BYTE *op = ostart; - const BYTE *litPtr = dctx->litPtr; - const BYTE *const litEnd = litPtr + dctx->litSize; - const BYTE *const base = (const BYTE *)(dctx->base); - const BYTE *const vBase = (const BYTE *)(dctx->vBase); - const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd); - unsigned const windowSize = dctx->fParams.windowSize; - int nbSeq; - - /* Build Decoding Tables */ - { - size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); - if (ZSTD_isError(seqHSize)) - return seqHSize; - ip += seqHSize; - } - - /* Regen sequences */ - if (nbSeq) { -#define STORED_SEQS 4 -#define STOSEQ_MASK (STORED_SEQS - 1) -#define ADVANCED_SEQS 4 - seq_t *sequences = (seq_t *)dctx->entropy.workspace; - int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS); - seqState_t seqState; - int seqNb; - ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.workspace) >= sizeof(seq_t) * STORED_SEQS); - dctx->fseEntropy = 1; - { - U32 i; - for (i = 0; i < ZSTD_REP_NUM; i++) - seqState.prevOffset[i] = dctx->entropy.rep[i]; - } - seqState.base = base; - seqState.pos = (size_t)(op - base); - seqState.gotoDict = (uPtrDiff)dictEnd - (uPtrDiff)base; /* cast to avoid undefined behaviour */ - CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected); - FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); - FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); - FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); - - /* prepare in advance */ - for (seqNb = 0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNb < seqAdvance; seqNb++) { - sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize); - } - if (seqNb < seqAdvance) - return ERROR(corruption_detected); - - /* decode and decompress */ - for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb < nbSeq; seqNb++) { - seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize); - size_t const oneSeqSize = - ZSTD_execSequenceLong(op, oend, sequences[(seqNb - ADVANCED_SEQS) & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); - if (ZSTD_isError(oneSeqSize)) - return oneSeqSize; - ZSTD_PREFETCH(sequence.match); - sequences[seqNb & STOSEQ_MASK] = sequence; - op += oneSeqSize; - } - if (seqNb < nbSeq) - return ERROR(corruption_detected); - - /* finish queue */ - seqNb -= seqAdvance; - for (; seqNb < nbSeq; seqNb++) { - size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[seqNb & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); - if (ZSTD_isError(oneSeqSize)) - return oneSeqSize; - op += oneSeqSize; - } - - /* save reps for next block */ - { - U32 i; - for (i = 0; i < ZSTD_REP_NUM; i++) - dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); - } - } - - /* last literal segment */ - { - size_t const lastLLSize = litEnd - litPtr; - if (lastLLSize > (size_t)(oend - op)) - return ERROR(dstSize_tooSmall); - memcpy(op, litPtr, lastLLSize); - op += lastLLSize; - } - - return op - ostart; -} - -static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) -{ /* blockType == blockCompressed */ - const BYTE *ip = (const BYTE *)src; - - if (srcSize >= ZSTD_BLOCKSIZE_ABSOLUTEMAX) - return ERROR(srcSize_wrong); - - /* Decode literals section */ - { - size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize); - if (ZSTD_isError(litCSize)) - return litCSize; - ip += litCSize; - srcSize -= litCSize; - } - if (sizeof(size_t) > 4) /* do not enable prefetching on 32-bits x86, as it's performance detrimental */ - /* likely because of register pressure */ - /* if that's the correct cause, then 32-bits ARM should be affected differently */ - /* it would be good to test this on ARM real hardware, to see if prefetch version improves speed */ - if (dctx->fParams.windowSize > (1 << 23)) - return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize); - return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize); -} - -static void ZSTD_checkContinuity(ZSTD_DCtx *dctx, const void *dst) -{ - if (dst != dctx->previousDstEnd) { /* not contiguous */ - dctx->dictEnd = dctx->previousDstEnd; - dctx->vBase = (const char *)dst - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base)); - dctx->base = dst; - dctx->previousDstEnd = dst; - } -} - -size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) -{ - size_t dSize; - ZSTD_checkContinuity(dctx, dst); - dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); - dctx->previousDstEnd = (char *)dst + dSize; - return dSize; -} - -/** ZSTD_insertBlock() : - insert `src` block into `dctx` history. Useful to track uncompressed blocks. */ -size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart, size_t blockSize) -{ - ZSTD_checkContinuity(dctx, blockStart); - dctx->previousDstEnd = (const char *)blockStart + blockSize; - return blockSize; -} - -size_t ZSTD_generateNxBytes(void *dst, size_t dstCapacity, BYTE byte, size_t length) -{ - if (length > dstCapacity) - return ERROR(dstSize_tooSmall); - memset(dst, byte, length); - return length; -} - -/** ZSTD_findFrameCompressedSize() : - * compatible with legacy mode - * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame - * `srcSize` must be at least as large as the frame contained - * @return : the compressed size of the frame starting at `src` */ -size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize) -{ - if (srcSize >= ZSTD_skippableHeaderSize && (ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { - return ZSTD_skippableHeaderSize + ZSTD_readLE32((const BYTE *)src + 4); - } else { - const BYTE *ip = (const BYTE *)src; - const BYTE *const ipstart = ip; - size_t remainingSize = srcSize; - ZSTD_frameParams fParams; - - size_t const headerSize = ZSTD_frameHeaderSize(ip, remainingSize); - if (ZSTD_isError(headerSize)) - return headerSize; - - /* Frame Header */ - { - size_t const ret = ZSTD_getFrameParams(&fParams, ip, remainingSize); - if (ZSTD_isError(ret)) - return ret; - if (ret > 0) - return ERROR(srcSize_wrong); - } - - ip += headerSize; - remainingSize -= headerSize; - - /* Loop on each block */ - while (1) { - blockProperties_t blockProperties; - size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); - if (ZSTD_isError(cBlockSize)) - return cBlockSize; - - if (ZSTD_blockHeaderSize + cBlockSize > remainingSize) - return ERROR(srcSize_wrong); - - ip += ZSTD_blockHeaderSize + cBlockSize; - remainingSize -= ZSTD_blockHeaderSize + cBlockSize; - - if (blockProperties.lastBlock) - break; - } - - if (fParams.checksumFlag) { /* Frame content checksum */ - if (remainingSize < 4) - return ERROR(srcSize_wrong); - ip += 4; - remainingSize -= 4; - } - - return ip - ipstart; - } -} - -/*! ZSTD_decompressFrame() : -* @dctx must be properly initialized */ -static size_t ZSTD_decompressFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void **srcPtr, size_t *srcSizePtr) -{ - const BYTE *ip = (const BYTE *)(*srcPtr); - BYTE *const ostart = (BYTE * const)dst; - BYTE *const oend = ostart + dstCapacity; - BYTE *op = ostart; - size_t remainingSize = *srcSizePtr; - - /* check */ - if (remainingSize < ZSTD_frameHeaderSize_min + ZSTD_blockHeaderSize) - return ERROR(srcSize_wrong); - - /* Frame Header */ - { - size_t const frameHeaderSize = ZSTD_frameHeaderSize(ip, ZSTD_frameHeaderSize_prefix); - if (ZSTD_isError(frameHeaderSize)) - return frameHeaderSize; - if (remainingSize < frameHeaderSize + ZSTD_blockHeaderSize) - return ERROR(srcSize_wrong); - CHECK_F(ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize)); - ip += frameHeaderSize; - remainingSize -= frameHeaderSize; - } - - /* Loop on each block */ - while (1) { - size_t decodedSize; - blockProperties_t blockProperties; - size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); - if (ZSTD_isError(cBlockSize)) - return cBlockSize; - - ip += ZSTD_blockHeaderSize; - remainingSize -= ZSTD_blockHeaderSize; - if (cBlockSize > remainingSize) - return ERROR(srcSize_wrong); - - switch (blockProperties.blockType) { - case bt_compressed: decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend - op, ip, cBlockSize); break; - case bt_raw: decodedSize = ZSTD_copyRawBlock(op, oend - op, ip, cBlockSize); break; - case bt_rle: decodedSize = ZSTD_generateNxBytes(op, oend - op, *ip, blockProperties.origSize); break; - case bt_reserved: - default: return ERROR(corruption_detected); - } - - if (ZSTD_isError(decodedSize)) - return decodedSize; - if (dctx->fParams.checksumFlag) - xxh64_update(&dctx->xxhState, op, decodedSize); - op += decodedSize; - ip += cBlockSize; - remainingSize -= cBlockSize; - if (blockProperties.lastBlock) - break; - } - - if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */ - U32 const checkCalc = (U32)xxh64_digest(&dctx->xxhState); - U32 checkRead; - if (remainingSize < 4) - return ERROR(checksum_wrong); - checkRead = ZSTD_readLE32(ip); - if (checkRead != checkCalc) - return ERROR(checksum_wrong); - ip += 4; - remainingSize -= 4; - } - - /* Allow caller to get size read */ - *srcPtr = ip; - *srcSizePtr = remainingSize; - return op - ostart; -} - -static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict); -static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict); - -static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize, - const ZSTD_DDict *ddict) -{ - void *const dststart = dst; - - if (ddict) { - if (dict) { - /* programmer error, these two cases should be mutually exclusive */ - return ERROR(GENERIC); - } - - dict = ZSTD_DDictDictContent(ddict); - dictSize = ZSTD_DDictDictSize(ddict); - } - - while (srcSize >= ZSTD_frameHeaderSize_prefix) { - U32 magicNumber; - - magicNumber = ZSTD_readLE32(src); - if (magicNumber != ZSTD_MAGICNUMBER) { - if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { - size_t skippableSize; - if (srcSize < ZSTD_skippableHeaderSize) - return ERROR(srcSize_wrong); - skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize; - if (srcSize < skippableSize) { - return ERROR(srcSize_wrong); - } - - src = (const BYTE *)src + skippableSize; - srcSize -= skippableSize; - continue; - } else { - return ERROR(prefix_unknown); - } - } - - if (ddict) { - /* we were called from ZSTD_decompress_usingDDict */ - ZSTD_refDDict(dctx, ddict); - } else { - /* this will initialize correctly with no dict if dict == NULL, so - * use this in all cases but ddict */ - CHECK_F(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize)); - } - ZSTD_checkContinuity(dctx, dst); - - { - const size_t res = ZSTD_decompressFrame(dctx, dst, dstCapacity, &src, &srcSize); - if (ZSTD_isError(res)) - return res; - /* don't need to bounds check this, ZSTD_decompressFrame will have - * already */ - dst = (BYTE *)dst + res; - dstCapacity -= res; - } - } - - if (srcSize) - return ERROR(srcSize_wrong); /* input not entirely consumed */ - - return (BYTE *)dst - (BYTE *)dststart; -} - -size_t ZSTD_decompress_usingDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize) -{ - return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, dict, dictSize, NULL); -} - -size_t ZSTD_decompressDCtx(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) -{ - return ZSTD_decompress_usingDict(dctx, dst, dstCapacity, src, srcSize, NULL, 0); -} - -/*-************************************** -* Advanced Streaming Decompression API -* Bufferless and synchronous -****************************************/ -size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx) { return dctx->expected; } - -ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx) -{ - switch (dctx->stage) { - default: /* should not happen */ - case ZSTDds_getFrameHeaderSize: - case ZSTDds_decodeFrameHeader: return ZSTDnit_frameHeader; - case ZSTDds_decodeBlockHeader: return ZSTDnit_blockHeader; - case ZSTDds_decompressBlock: return ZSTDnit_block; - case ZSTDds_decompressLastBlock: return ZSTDnit_lastBlock; - case ZSTDds_checkChecksum: return ZSTDnit_checksum; - case ZSTDds_decodeSkippableHeader: - case ZSTDds_skipFrame: return ZSTDnit_skippableFrame; - } -} - -int ZSTD_isSkipFrame(ZSTD_DCtx *dctx) { return dctx->stage == ZSTDds_skipFrame; } /* for zbuff */ - -/** ZSTD_decompressContinue() : -* @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity) -* or an error code, which can be tested using ZSTD_isError() */ -size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) -{ - /* Sanity check */ - if (srcSize != dctx->expected) - return ERROR(srcSize_wrong); - if (dstCapacity) - ZSTD_checkContinuity(dctx, dst); - - switch (dctx->stage) { - case ZSTDds_getFrameHeaderSize: - if (srcSize != ZSTD_frameHeaderSize_prefix) - return ERROR(srcSize_wrong); /* impossible */ - if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ - memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); - dctx->expected = ZSTD_skippableHeaderSize - ZSTD_frameHeaderSize_prefix; /* magic number + skippable frame length */ - dctx->stage = ZSTDds_decodeSkippableHeader; - return 0; - } - dctx->headerSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_prefix); - if (ZSTD_isError(dctx->headerSize)) - return dctx->headerSize; - memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); - if (dctx->headerSize > ZSTD_frameHeaderSize_prefix) { - dctx->expected = dctx->headerSize - ZSTD_frameHeaderSize_prefix; - dctx->stage = ZSTDds_decodeFrameHeader; - return 0; - } - dctx->expected = 0; /* not necessary to copy more */ - fallthrough; - - case ZSTDds_decodeFrameHeader: - memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); - CHECK_F(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize)); - dctx->expected = ZSTD_blockHeaderSize; - dctx->stage = ZSTDds_decodeBlockHeader; - return 0; - - case ZSTDds_decodeBlockHeader: { - blockProperties_t bp; - size_t const cBlockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp); - if (ZSTD_isError(cBlockSize)) - return cBlockSize; - dctx->expected = cBlockSize; - dctx->bType = bp.blockType; - dctx->rleSize = bp.origSize; - if (cBlockSize) { - dctx->stage = bp.lastBlock ? ZSTDds_decompressLastBlock : ZSTDds_decompressBlock; - return 0; - } - /* empty block */ - if (bp.lastBlock) { - if (dctx->fParams.checksumFlag) { - dctx->expected = 4; - dctx->stage = ZSTDds_checkChecksum; - } else { - dctx->expected = 0; /* end of frame */ - dctx->stage = ZSTDds_getFrameHeaderSize; - } - } else { - dctx->expected = 3; /* go directly to next header */ - dctx->stage = ZSTDds_decodeBlockHeader; - } - return 0; - } - case ZSTDds_decompressLastBlock: - case ZSTDds_decompressBlock: { - size_t rSize; - switch (dctx->bType) { - case bt_compressed: rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); break; - case bt_raw: rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize); break; - case bt_rle: rSize = ZSTD_setRleBlock(dst, dstCapacity, src, srcSize, dctx->rleSize); break; - case bt_reserved: /* should never happen */ - default: return ERROR(corruption_detected); - } - if (ZSTD_isError(rSize)) - return rSize; - if (dctx->fParams.checksumFlag) - xxh64_update(&dctx->xxhState, dst, rSize); - - if (dctx->stage == ZSTDds_decompressLastBlock) { /* end of frame */ - if (dctx->fParams.checksumFlag) { /* another round for frame checksum */ - dctx->expected = 4; - dctx->stage = ZSTDds_checkChecksum; - } else { - dctx->expected = 0; /* ends here */ - dctx->stage = ZSTDds_getFrameHeaderSize; - } - } else { - dctx->stage = ZSTDds_decodeBlockHeader; - dctx->expected = ZSTD_blockHeaderSize; - dctx->previousDstEnd = (char *)dst + rSize; - } - return rSize; - } - case ZSTDds_checkChecksum: { - U32 const h32 = (U32)xxh64_digest(&dctx->xxhState); - U32 const check32 = ZSTD_readLE32(src); /* srcSize == 4, guaranteed by dctx->expected */ - if (check32 != h32) - return ERROR(checksum_wrong); - dctx->expected = 0; - dctx->stage = ZSTDds_getFrameHeaderSize; - return 0; - } - case ZSTDds_decodeSkippableHeader: { - memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); - dctx->expected = ZSTD_readLE32(dctx->headerBuffer + 4); - dctx->stage = ZSTDds_skipFrame; - return 0; - } - case ZSTDds_skipFrame: { - dctx->expected = 0; - dctx->stage = ZSTDds_getFrameHeaderSize; - return 0; - } - default: - return ERROR(GENERIC); /* impossible */ - } -} - -static size_t ZSTD_refDictContent(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) -{ - dctx->dictEnd = dctx->previousDstEnd; - dctx->vBase = (const char *)dict - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base)); - dctx->base = dict; - dctx->previousDstEnd = (const char *)dict + dictSize; - return 0; -} - -/* ZSTD_loadEntropy() : - * dict : must point at beginning of a valid zstd dictionary - * @return : size of entropy tables read */ -static size_t ZSTD_loadEntropy(ZSTD_entropyTables_t *entropy, const void *const dict, size_t const dictSize) -{ - const BYTE *dictPtr = (const BYTE *)dict; - const BYTE *const dictEnd = dictPtr + dictSize; - - if (dictSize <= 8) - return ERROR(dictionary_corrupted); - dictPtr += 8; /* skip header = magic + dictID */ - - { - size_t const hSize = HUF_readDTableX4_wksp(entropy->hufTable, dictPtr, dictEnd - dictPtr, entropy->workspace, sizeof(entropy->workspace)); - if (HUF_isError(hSize)) - return ERROR(dictionary_corrupted); - dictPtr += hSize; - } - - { - short offcodeNCount[MaxOff + 1]; - U32 offcodeMaxValue = MaxOff, offcodeLog; - size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd - dictPtr); - if (FSE_isError(offcodeHeaderSize)) - return ERROR(dictionary_corrupted); - if (offcodeLog > OffFSELog) - return ERROR(dictionary_corrupted); - CHECK_E(FSE_buildDTable_wksp(entropy->OFTable, offcodeNCount, offcodeMaxValue, offcodeLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); - dictPtr += offcodeHeaderSize; - } - - { - short matchlengthNCount[MaxML + 1]; - unsigned matchlengthMaxValue = MaxML, matchlengthLog; - size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd - dictPtr); - if (FSE_isError(matchlengthHeaderSize)) - return ERROR(dictionary_corrupted); - if (matchlengthLog > MLFSELog) - return ERROR(dictionary_corrupted); - CHECK_E(FSE_buildDTable_wksp(entropy->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); - dictPtr += matchlengthHeaderSize; - } - - { - short litlengthNCount[MaxLL + 1]; - unsigned litlengthMaxValue = MaxLL, litlengthLog; - size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd - dictPtr); - if (FSE_isError(litlengthHeaderSize)) - return ERROR(dictionary_corrupted); - if (litlengthLog > LLFSELog) - return ERROR(dictionary_corrupted); - CHECK_E(FSE_buildDTable_wksp(entropy->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); - dictPtr += litlengthHeaderSize; - } - - if (dictPtr + 12 > dictEnd) - return ERROR(dictionary_corrupted); - { - int i; - size_t const dictContentSize = (size_t)(dictEnd - (dictPtr + 12)); - for (i = 0; i < 3; i++) { - U32 const rep = ZSTD_readLE32(dictPtr); - dictPtr += 4; - if (rep == 0 || rep >= dictContentSize) - return ERROR(dictionary_corrupted); - entropy->rep[i] = rep; - } - } - - return dictPtr - (const BYTE *)dict; -} - -static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) -{ - if (dictSize < 8) - return ZSTD_refDictContent(dctx, dict, dictSize); - { - U32 const magic = ZSTD_readLE32(dict); - if (magic != ZSTD_DICT_MAGIC) { - return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */ - } - } - dctx->dictID = ZSTD_readLE32((const char *)dict + 4); - - /* load entropy tables */ - { - size_t const eSize = ZSTD_loadEntropy(&dctx->entropy, dict, dictSize); - if (ZSTD_isError(eSize)) - return ERROR(dictionary_corrupted); - dict = (const char *)dict + eSize; - dictSize -= eSize; - } - dctx->litEntropy = dctx->fseEntropy = 1; - - /* reference dictionary content */ - return ZSTD_refDictContent(dctx, dict, dictSize); -} - -size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) -{ - CHECK_F(ZSTD_decompressBegin(dctx)); - if (dict && dictSize) - CHECK_E(ZSTD_decompress_insertDictionary(dctx, dict, dictSize), dictionary_corrupted); - return 0; -} - -/* ====== ZSTD_DDict ====== */ - -struct ZSTD_DDict_s { - void *dictBuffer; - const void *dictContent; - size_t dictSize; - ZSTD_entropyTables_t entropy; - U32 dictID; - U32 entropyPresent; - ZSTD_customMem cMem; -}; /* typedef'd to ZSTD_DDict within "zstd.h" */ - -size_t ZSTD_DDictWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DDict)); } - -static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict) { return ddict->dictContent; } - -static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict) { return ddict->dictSize; } - -static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict) -{ - ZSTD_decompressBegin(dstDCtx); /* init */ - if (ddict) { /* support refDDict on NULL */ - dstDCtx->dictID = ddict->dictID; - dstDCtx->base = ddict->dictContent; - dstDCtx->vBase = ddict->dictContent; - dstDCtx->dictEnd = (const BYTE *)ddict->dictContent + ddict->dictSize; - dstDCtx->previousDstEnd = dstDCtx->dictEnd; - if (ddict->entropyPresent) { - dstDCtx->litEntropy = 1; - dstDCtx->fseEntropy = 1; - dstDCtx->LLTptr = ddict->entropy.LLTable; - dstDCtx->MLTptr = ddict->entropy.MLTable; - dstDCtx->OFTptr = ddict->entropy.OFTable; - dstDCtx->HUFptr = ddict->entropy.hufTable; - dstDCtx->entropy.rep[0] = ddict->entropy.rep[0]; - dstDCtx->entropy.rep[1] = ddict->entropy.rep[1]; - dstDCtx->entropy.rep[2] = ddict->entropy.rep[2]; - } else { - dstDCtx->litEntropy = 0; - dstDCtx->fseEntropy = 0; - } - } -} - -static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict *ddict) -{ - ddict->dictID = 0; - ddict->entropyPresent = 0; - if (ddict->dictSize < 8) - return 0; - { - U32 const magic = ZSTD_readLE32(ddict->dictContent); - if (magic != ZSTD_DICT_MAGIC) - return 0; /* pure content mode */ - } - ddict->dictID = ZSTD_readLE32((const char *)ddict->dictContent + 4); - - /* load entropy tables */ - CHECK_E(ZSTD_loadEntropy(&ddict->entropy, ddict->dictContent, ddict->dictSize), dictionary_corrupted); - ddict->entropyPresent = 1; - return 0; -} - -static ZSTD_DDict *ZSTD_createDDict_advanced(const void *dict, size_t dictSize, unsigned byReference, ZSTD_customMem customMem) -{ - if (!customMem.customAlloc || !customMem.customFree) - return NULL; - - { - ZSTD_DDict *const ddict = (ZSTD_DDict *)ZSTD_malloc(sizeof(ZSTD_DDict), customMem); - if (!ddict) - return NULL; - ddict->cMem = customMem; - - if ((byReference) || (!dict) || (!dictSize)) { - ddict->dictBuffer = NULL; - ddict->dictContent = dict; - } else { - void *const internalBuffer = ZSTD_malloc(dictSize, customMem); - if (!internalBuffer) { - ZSTD_freeDDict(ddict); - return NULL; - } - memcpy(internalBuffer, dict, dictSize); - ddict->dictBuffer = internalBuffer; - ddict->dictContent = internalBuffer; - } - ddict->dictSize = dictSize; - ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ - /* parse dictionary content */ - { - size_t const errorCode = ZSTD_loadEntropy_inDDict(ddict); - if (ZSTD_isError(errorCode)) { - ZSTD_freeDDict(ddict); - return NULL; - } - } - - return ddict; - } -} - -/*! ZSTD_initDDict() : -* Create a digested dictionary, to start decompression without startup delay. -* `dict` content is copied inside DDict. -* Consequently, `dict` can be released after `ZSTD_DDict` creation */ -ZSTD_DDict *ZSTD_initDDict(const void *dict, size_t dictSize, void *workspace, size_t workspaceSize) -{ - ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); - return ZSTD_createDDict_advanced(dict, dictSize, 1, stackMem); -} - -size_t ZSTD_freeDDict(ZSTD_DDict *ddict) -{ - if (ddict == NULL) - return 0; /* support free on NULL */ - { - ZSTD_customMem const cMem = ddict->cMem; - ZSTD_free(ddict->dictBuffer, cMem); - ZSTD_free(ddict, cMem); - return 0; - } -} - -/*! ZSTD_getDictID_fromDict() : - * Provides the dictID stored within dictionary. - * if @return == 0, the dictionary is not conformant with Zstandard specification. - * It can still be loaded, but as a content-only dictionary. */ -unsigned ZSTD_getDictID_fromDict(const void *dict, size_t dictSize) -{ - if (dictSize < 8) - return 0; - if (ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC) - return 0; - return ZSTD_readLE32((const char *)dict + 4); -} - -/*! ZSTD_getDictID_fromDDict() : - * Provides the dictID of the dictionary loaded into `ddict`. - * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty. - * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ -unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict) -{ - if (ddict == NULL) - return 0; - return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize); -} - -/*! ZSTD_getDictID_fromFrame() : - * Provides the dictID required to decompressed the frame stored within `src`. - * If @return == 0, the dictID could not be decoded. - * This could for one of the following reasons : - * - The frame does not require a dictionary to be decoded (most common case). - * - The frame was built with dictID intentionally removed. Whatever dictionary is necessary is a hidden information. - * Note : this use case also happens when using a non-conformant dictionary. - * - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`). - * - This is not a Zstandard frame. - * When identifying the exact failure cause, it's possible to used ZSTD_getFrameParams(), which will provide a more precise error code. */ -unsigned ZSTD_getDictID_fromFrame(const void *src, size_t srcSize) -{ - ZSTD_frameParams zfp = {0, 0, 0, 0}; - size_t const hError = ZSTD_getFrameParams(&zfp, src, srcSize); - if (ZSTD_isError(hError)) - return 0; - return zfp.dictID; -} - -/*! ZSTD_decompress_usingDDict() : -* Decompression using a pre-digested Dictionary -* Use dictionary without significant overhead. */ -size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_DDict *ddict) -{ - /* pass content and size in case legacy frames are encountered */ - return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, NULL, 0, ddict); -} - -/*===================================== -* Streaming decompression -*====================================*/ - -typedef enum { zdss_init, zdss_loadHeader, zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage; - -/* *** Resource management *** */ -struct ZSTD_DStream_s { - ZSTD_DCtx *dctx; - ZSTD_DDict *ddictLocal; - const ZSTD_DDict *ddict; - ZSTD_frameParams fParams; - ZSTD_dStreamStage stage; - char *inBuff; - size_t inBuffSize; - size_t inPos; - size_t maxWindowSize; - char *outBuff; - size_t outBuffSize; - size_t outStart; - size_t outEnd; - size_t blockSize; - BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; /* tmp buffer to store frame header */ - size_t lhSize; - ZSTD_customMem customMem; - void *legacyContext; - U32 previousLegacyVersion; - U32 legacyVersion; - U32 hostageByte; -}; /* typedef'd to ZSTD_DStream within "zstd.h" */ - -size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize) -{ - size_t const blockSize = MIN(maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); - size_t const inBuffSize = blockSize; - size_t const outBuffSize = maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; - return ZSTD_DCtxWorkspaceBound() + ZSTD_ALIGN(sizeof(ZSTD_DStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize); -} - -static ZSTD_DStream *ZSTD_createDStream_advanced(ZSTD_customMem customMem) -{ - ZSTD_DStream *zds; - - if (!customMem.customAlloc || !customMem.customFree) - return NULL; - - zds = (ZSTD_DStream *)ZSTD_malloc(sizeof(ZSTD_DStream), customMem); - if (zds == NULL) - return NULL; - memset(zds, 0, sizeof(ZSTD_DStream)); - memcpy(&zds->customMem, &customMem, sizeof(ZSTD_customMem)); - zds->dctx = ZSTD_createDCtx_advanced(customMem); - if (zds->dctx == NULL) { - ZSTD_freeDStream(zds); - return NULL; - } - zds->stage = zdss_init; - zds->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT; - return zds; -} - -ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace, size_t workspaceSize) -{ - ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); - ZSTD_DStream *zds = ZSTD_createDStream_advanced(stackMem); - if (!zds) { - return NULL; - } - - zds->maxWindowSize = maxWindowSize; - zds->stage = zdss_loadHeader; - zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; - ZSTD_freeDDict(zds->ddictLocal); - zds->ddictLocal = NULL; - zds->ddict = zds->ddictLocal; - zds->legacyVersion = 0; - zds->hostageByte = 0; - - { - size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); - size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; - - zds->inBuff = (char *)ZSTD_malloc(blockSize, zds->customMem); - zds->inBuffSize = blockSize; - zds->outBuff = (char *)ZSTD_malloc(neededOutSize, zds->customMem); - zds->outBuffSize = neededOutSize; - if (zds->inBuff == NULL || zds->outBuff == NULL) { - ZSTD_freeDStream(zds); - return NULL; - } - } - return zds; -} - -ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize, const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize) -{ - ZSTD_DStream *zds = ZSTD_initDStream(maxWindowSize, workspace, workspaceSize); - if (zds) { - zds->ddict = ddict; - } - return zds; -} - -size_t ZSTD_freeDStream(ZSTD_DStream *zds) -{ - if (zds == NULL) - return 0; /* support free on null */ - { - ZSTD_customMem const cMem = zds->customMem; - ZSTD_freeDCtx(zds->dctx); - zds->dctx = NULL; - ZSTD_freeDDict(zds->ddictLocal); - zds->ddictLocal = NULL; - ZSTD_free(zds->inBuff, cMem); - zds->inBuff = NULL; - ZSTD_free(zds->outBuff, cMem); - zds->outBuff = NULL; - ZSTD_free(zds, cMem); - return 0; - } -} - -/* *** Initialization *** */ - -size_t ZSTD_DStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX + ZSTD_blockHeaderSize; } -size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; } - -size_t ZSTD_resetDStream(ZSTD_DStream *zds) -{ - zds->stage = zdss_loadHeader; - zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; - zds->legacyVersion = 0; - zds->hostageByte = 0; - return ZSTD_frameHeaderSize_prefix; -} - -/* ***** Decompression ***** */ - -ZSTD_STATIC size_t ZSTD_limitCopy(void *dst, size_t dstCapacity, const void *src, size_t srcSize) -{ - size_t const length = MIN(dstCapacity, srcSize); - memcpy(dst, src, length); - return length; -} - -size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inBuffer *input) -{ - const char *const istart = (const char *)(input->src) + input->pos; - const char *const iend = (const char *)(input->src) + input->size; - const char *ip = istart; - char *const ostart = (char *)(output->dst) + output->pos; - char *const oend = (char *)(output->dst) + output->size; - char *op = ostart; - U32 someMoreWork = 1; - - while (someMoreWork) { - switch (zds->stage) { - case zdss_init: - ZSTD_resetDStream(zds); /* transparent reset on starting decoding a new frame */ - fallthrough; - - case zdss_loadHeader: { - size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize); - if (ZSTD_isError(hSize)) - return hSize; - if (hSize != 0) { /* need more input */ - size_t const toLoad = hSize - zds->lhSize; /* if hSize!=0, hSize > zds->lhSize */ - if (toLoad > (size_t)(iend - ip)) { /* not enough input to load full header */ - memcpy(zds->headerBuffer + zds->lhSize, ip, iend - ip); - zds->lhSize += iend - ip; - input->pos = input->size; - return (MAX(ZSTD_frameHeaderSize_min, hSize) - zds->lhSize) + - ZSTD_blockHeaderSize; /* remaining header bytes + next block header */ - } - memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad); - zds->lhSize = hSize; - ip += toLoad; - break; - } - - /* check for single-pass mode opportunity */ - if (zds->fParams.frameContentSize && zds->fParams.windowSize /* skippable frame if == 0 */ - && (U64)(size_t)(oend - op) >= zds->fParams.frameContentSize) { - size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend - istart); - if (cSize <= (size_t)(iend - istart)) { - size_t const decompressedSize = ZSTD_decompress_usingDDict(zds->dctx, op, oend - op, istart, cSize, zds->ddict); - if (ZSTD_isError(decompressedSize)) - return decompressedSize; - ip = istart + cSize; - op += decompressedSize; - zds->dctx->expected = 0; - zds->stage = zdss_init; - someMoreWork = 0; - break; - } - } - - /* Consume header */ - ZSTD_refDDict(zds->dctx, zds->ddict); - { - size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); /* == ZSTD_frameHeaderSize_prefix */ - CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer, h1Size)); - { - size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); - CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer + h1Size, h2Size)); - } - } - - zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN); - if (zds->fParams.windowSize > zds->maxWindowSize) - return ERROR(frameParameter_windowTooLarge); - - /* Buffers are preallocated, but double check */ - { - size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); - size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; - if (zds->inBuffSize < blockSize) { - return ERROR(GENERIC); - } - if (zds->outBuffSize < neededOutSize) { - return ERROR(GENERIC); - } - zds->blockSize = blockSize; - } - zds->stage = zdss_read; - } - fallthrough; - - case zdss_read: { - size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx); - if (neededInSize == 0) { /* end of frame */ - zds->stage = zdss_init; - someMoreWork = 0; - break; - } - if ((size_t)(iend - ip) >= neededInSize) { /* decode directly from src */ - const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx); - size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, - (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart), ip, neededInSize); - if (ZSTD_isError(decodedSize)) - return decodedSize; - ip += neededInSize; - if (!decodedSize && !isSkipFrame) - break; /* this was just a header */ - zds->outEnd = zds->outStart + decodedSize; - zds->stage = zdss_flush; - break; - } - if (ip == iend) { - someMoreWork = 0; - break; - } /* no more input */ - zds->stage = zdss_load; - /* pass-through */ - } - fallthrough; - - case zdss_load: { - size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx); - size_t const toLoad = neededInSize - zds->inPos; /* should always be <= remaining space within inBuff */ - size_t loadedSize; - if (toLoad > zds->inBuffSize - zds->inPos) - return ERROR(corruption_detected); /* should never happen */ - loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, iend - ip); - ip += loadedSize; - zds->inPos += loadedSize; - if (loadedSize < toLoad) { - someMoreWork = 0; - break; - } /* not enough input, wait for more */ - - /* decode loaded input */ - { - const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx); - size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart, - zds->inBuff, neededInSize); - if (ZSTD_isError(decodedSize)) - return decodedSize; - zds->inPos = 0; /* input is consumed */ - if (!decodedSize && !isSkipFrame) { - zds->stage = zdss_read; - break; - } /* this was just a header */ - zds->outEnd = zds->outStart + decodedSize; - zds->stage = zdss_flush; - /* pass-through */ - } - } - fallthrough; - - case zdss_flush: { - size_t const toFlushSize = zds->outEnd - zds->outStart; - size_t const flushedSize = ZSTD_limitCopy(op, oend - op, zds->outBuff + zds->outStart, toFlushSize); - op += flushedSize; - zds->outStart += flushedSize; - if (flushedSize == toFlushSize) { /* flush completed */ - zds->stage = zdss_read; - if (zds->outStart + zds->blockSize > zds->outBuffSize) - zds->outStart = zds->outEnd = 0; - break; - } - /* cannot complete flush */ - someMoreWork = 0; - break; - } - default: - return ERROR(GENERIC); /* impossible */ - } - } - - /* result */ - input->pos += (size_t)(ip - istart); - output->pos += (size_t)(op - ostart); - { - size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds->dctx); - if (!nextSrcSizeHint) { /* frame fully decoded */ - if (zds->outEnd == zds->outStart) { /* output fully flushed */ - if (zds->hostageByte) { - if (input->pos >= input->size) { - zds->stage = zdss_read; - return 1; - } /* can't release hostage (not present) */ - input->pos++; /* release hostage */ - } - return 0; - } - if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */ - input->pos--; /* note : pos > 0, otherwise, impossible to finish reading last block */ - zds->hostageByte = 1; - } - return 1; - } - nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->dctx) == ZSTDnit_block); /* preload header of next block */ - if (zds->inPos > nextSrcSizeHint) - return ERROR(GENERIC); /* should never happen */ - nextSrcSizeHint -= zds->inPos; /* already loaded*/ - return nextSrcSizeHint; - } -} - -EXPORT_SYMBOL(ZSTD_DCtxWorkspaceBound); -EXPORT_SYMBOL(ZSTD_initDCtx); -EXPORT_SYMBOL(ZSTD_decompressDCtx); -EXPORT_SYMBOL(ZSTD_decompress_usingDict); - -EXPORT_SYMBOL(ZSTD_DDictWorkspaceBound); -EXPORT_SYMBOL(ZSTD_initDDict); -EXPORT_SYMBOL(ZSTD_decompress_usingDDict); - -EXPORT_SYMBOL(ZSTD_DStreamWorkspaceBound); -EXPORT_SYMBOL(ZSTD_initDStream); -EXPORT_SYMBOL(ZSTD_initDStream_usingDDict); -EXPORT_SYMBOL(ZSTD_resetDStream); -EXPORT_SYMBOL(ZSTD_decompressStream); -EXPORT_SYMBOL(ZSTD_DStreamInSize); -EXPORT_SYMBOL(ZSTD_DStreamOutSize); - -EXPORT_SYMBOL(ZSTD_findFrameCompressedSize); -EXPORT_SYMBOL(ZSTD_getFrameContentSize); -EXPORT_SYMBOL(ZSTD_findDecompressedSize); - -EXPORT_SYMBOL(ZSTD_isFrame); -EXPORT_SYMBOL(ZSTD_getDictID_fromDict); -EXPORT_SYMBOL(ZSTD_getDictID_fromDDict); -EXPORT_SYMBOL(ZSTD_getDictID_fromFrame); - -EXPORT_SYMBOL(ZSTD_getFrameParams); -EXPORT_SYMBOL(ZSTD_decompressBegin); -EXPORT_SYMBOL(ZSTD_decompressBegin_usingDict); -EXPORT_SYMBOL(ZSTD_copyDCtx); -EXPORT_SYMBOL(ZSTD_nextSrcSizeToDecompress); -EXPORT_SYMBOL(ZSTD_decompressContinue); -EXPORT_SYMBOL(ZSTD_nextInputType); - -EXPORT_SYMBOL(ZSTD_decompressBlock); -EXPORT_SYMBOL(ZSTD_insertBlock); - -MODULE_LICENSE("Dual BSD/GPL"); -MODULE_DESCRIPTION("Zstd Decompressor"); |