diff options
Diffstat (limited to 'vendor/github.com/DataDog/zstd/zstd_decompress.c')
| -rw-r--r-- | vendor/github.com/DataDog/zstd/zstd_decompress.c | 1765 |
1 files changed, 0 insertions, 1765 deletions
diff --git a/vendor/github.com/DataDog/zstd/zstd_decompress.c b/vendor/github.com/DataDog/zstd/zstd_decompress.c deleted file mode 100644 index 675596f5a..000000000 --- a/vendor/github.com/DataDog/zstd/zstd_decompress.c +++ /dev/null @@ -1,1765 +0,0 @@ -/* - * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. - * All rights reserved. - * - * This source code is licensed under both the BSD-style license (found in the - * LICENSE file in the root directory of this source tree) and the GPLv2 (found - * in the COPYING file in the root directory of this source tree). - * You may select, at your option, one of the above-listed licenses. - */ - - -/* *************************************************************** -* Tuning parameters -*****************************************************************/ -/*! - * HEAPMODE : - * Select how default decompression function ZSTD_decompress() allocates its context, - * on stack (0), or into heap (1, default; requires malloc()). - * Note that functions with explicit context such as ZSTD_decompressDCtx() are unaffected. - */ -#ifndef ZSTD_HEAPMODE -# define ZSTD_HEAPMODE 1 -#endif - -/*! -* LEGACY_SUPPORT : -* if set to 1+, ZSTD_decompress() can decode older formats (v0.1+) -*/ -#ifndef ZSTD_LEGACY_SUPPORT -# define ZSTD_LEGACY_SUPPORT 0 -#endif - -/*! - * MAXWINDOWSIZE_DEFAULT : - * maximum window size accepted by DStream __by default__. - * Frames requiring more memory will be rejected. - * It's possible to set a different limit using ZSTD_DCtx_setMaxWindowSize(). - */ -#ifndef ZSTD_MAXWINDOWSIZE_DEFAULT -# define ZSTD_MAXWINDOWSIZE_DEFAULT (((U32)1 << ZSTD_WINDOWLOG_LIMIT_DEFAULT) + 1) -#endif - -/*! - * NO_FORWARD_PROGRESS_MAX : - * maximum allowed nb of calls to ZSTD_decompressStream() - * without any forward progress - * (defined as: no byte read from input, and no byte flushed to output) - * before triggering an error. - */ -#ifndef ZSTD_NO_FORWARD_PROGRESS_MAX -# define ZSTD_NO_FORWARD_PROGRESS_MAX 16 -#endif - - -/*-******************************************************* -* Dependencies -*********************************************************/ -#include <string.h> /* memcpy, memmove, memset */ -#include "cpu.h" /* bmi2 */ -#include "mem.h" /* low level memory routines */ -#define FSE_STATIC_LINKING_ONLY -#include "fse.h" -#define HUF_STATIC_LINKING_ONLY -#include "huf.h" -#include "zstd_internal.h" /* blockProperties_t */ -#include "zstd_decompress_internal.h" /* ZSTD_DCtx */ -#include "zstd_ddict.h" /* ZSTD_DDictDictContent */ -#include "zstd_decompress_block.h" /* ZSTD_decompressBlock_internal */ - -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) -# include "zstd_legacy.h" -#endif - - -/*-************************************************************* -* Context management -***************************************************************/ -size_t ZSTD_sizeof_DCtx (const ZSTD_DCtx* dctx) -{ - if (dctx==NULL) return 0; /* support sizeof NULL */ - return sizeof(*dctx) - + ZSTD_sizeof_DDict(dctx->ddictLocal) - + dctx->inBuffSize + dctx->outBuffSize; -} - -size_t ZSTD_estimateDCtxSize(void) { return sizeof(ZSTD_DCtx); } - - -static size_t ZSTD_startingInputLength(ZSTD_format_e format) -{ - size_t const startingInputLength = (format==ZSTD_f_zstd1_magicless) ? - ZSTD_FRAMEHEADERSIZE_PREFIX - ZSTD_FRAMEIDSIZE : - ZSTD_FRAMEHEADERSIZE_PREFIX; - ZSTD_STATIC_ASSERT(ZSTD_FRAMEHEADERSIZE_PREFIX >= ZSTD_FRAMEIDSIZE); - /* only supports formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless */ - assert( (format == ZSTD_f_zstd1) || (format == ZSTD_f_zstd1_magicless) ); - return startingInputLength; -} - -static void ZSTD_initDCtx_internal(ZSTD_DCtx* dctx) -{ - dctx->format = ZSTD_f_zstd1; /* ZSTD_decompressBegin() invokes ZSTD_startingInputLength() with argument dctx->format */ - dctx->staticSize = 0; - dctx->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT; - dctx->ddict = NULL; - dctx->ddictLocal = NULL; - dctx->dictEnd = NULL; - dctx->ddictIsCold = 0; - dctx->dictUses = ZSTD_dont_use; - dctx->inBuff = NULL; - dctx->inBuffSize = 0; - dctx->outBuffSize = 0; - dctx->streamStage = zdss_init; - dctx->legacyContext = NULL; - dctx->previousLegacyVersion = 0; - dctx->noForwardProgress = 0; - dctx->bmi2 = ZSTD_cpuid_bmi2(ZSTD_cpuid()); -} - -ZSTD_DCtx* ZSTD_initStaticDCtx(void *workspace, size_t workspaceSize) -{ - ZSTD_DCtx* const dctx = (ZSTD_DCtx*) workspace; - - if ((size_t)workspace & 7) return NULL; /* 8-aligned */ - if (workspaceSize < sizeof(ZSTD_DCtx)) return NULL; /* minimum size */ - - ZSTD_initDCtx_internal(dctx); - dctx->staticSize = workspaceSize; - dctx->inBuff = (char*)(dctx+1); - return dctx; -} - -ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem) -{ - if (!customMem.customAlloc ^ !customMem.customFree) return NULL; - - { ZSTD_DCtx* const dctx = (ZSTD_DCtx*)ZSTD_malloc(sizeof(*dctx), customMem); - if (!dctx) return NULL; - dctx->customMem = customMem; - ZSTD_initDCtx_internal(dctx); - return dctx; - } -} - -ZSTD_DCtx* ZSTD_createDCtx(void) -{ - DEBUGLOG(3, "ZSTD_createDCtx"); - return ZSTD_createDCtx_advanced(ZSTD_defaultCMem); -} - -static void ZSTD_clearDict(ZSTD_DCtx* dctx) -{ - ZSTD_freeDDict(dctx->ddictLocal); - dctx->ddictLocal = NULL; - dctx->ddict = NULL; - dctx->dictUses = ZSTD_dont_use; -} - -size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx) -{ - if (dctx==NULL) return 0; /* support free on NULL */ - RETURN_ERROR_IF(dctx->staticSize, memory_allocation, "not compatible with static DCtx"); - { ZSTD_customMem const cMem = dctx->customMem; - ZSTD_clearDict(dctx); - ZSTD_free(dctx->inBuff, cMem); - dctx->inBuff = NULL; -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (dctx->legacyContext) - ZSTD_freeLegacyStreamContext(dctx->legacyContext, dctx->previousLegacyVersion); -#endif - ZSTD_free(dctx, cMem); - return 0; - } -} - -/* no longer useful */ -void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx) -{ - size_t const toCopy = (size_t)((char*)(&dstDCtx->inBuff) - (char*)dstDCtx); - memcpy(dstDCtx, srcDCtx, toCopy); /* no need to copy workspace */ -} - - -/*-************************************************************* - * Frame header decoding - ***************************************************************/ - -/*! 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 < ZSTD_FRAMEIDSIZE) return 0; - { U32 const magic = MEM_readLE32(buffer); - if (magic == ZSTD_MAGICNUMBER) return 1; - if ((magic & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) return 1; - } -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (ZSTD_isLegacy(buffer, size)) return 1; -#endif - return 0; -} - -/** ZSTD_frameHeaderSize_internal() : - * srcSize must be large enough to reach header size fields. - * note : only works for formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless. - * @return : size of the Frame Header - * or an error code, which can be tested with ZSTD_isError() */ -static size_t ZSTD_frameHeaderSize_internal(const void* src, size_t srcSize, ZSTD_format_e format) -{ - size_t const minInputSize = ZSTD_startingInputLength(format); - RETURN_ERROR_IF(srcSize < minInputSize, srcSize_wrong); - - { BYTE const fhd = ((const BYTE*)src)[minInputSize-1]; - U32 const dictID= fhd & 3; - U32 const singleSegment = (fhd >> 5) & 1; - U32 const fcsId = fhd >> 6; - return minInputSize + !singleSegment - + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId] - + (singleSegment && !fcsId); - } -} - -/** ZSTD_frameHeaderSize() : - * srcSize must be >= ZSTD_frameHeaderSize_prefix. - * @return : size of the Frame Header, - * or an error code (if srcSize is too small) */ -size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize) -{ - return ZSTD_frameHeaderSize_internal(src, srcSize, ZSTD_f_zstd1); -} - - -/** ZSTD_getFrameHeader_advanced() : - * decode Frame Header, or require larger `srcSize`. - * note : only works for formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless - * @return : 0, `zfhPtr` is correctly filled, - * >0, `srcSize` is too small, value is wanted `srcSize` amount, - * or an error code, which can be tested using ZSTD_isError() */ -size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format) -{ - const BYTE* ip = (const BYTE*)src; - size_t const minInputSize = ZSTD_startingInputLength(format); - - memset(zfhPtr, 0, sizeof(*zfhPtr)); /* not strictly necessary, but static analyzer do not understand that zfhPtr is only going to be read only if return value is zero, since they are 2 different signals */ - if (srcSize < minInputSize) return minInputSize; - RETURN_ERROR_IF(src==NULL, GENERIC, "invalid parameter"); - - if ( (format != ZSTD_f_zstd1_magicless) - && (MEM_readLE32(src) != ZSTD_MAGICNUMBER) ) { - if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { - /* skippable frame */ - if (srcSize < ZSTD_SKIPPABLEHEADERSIZE) - return ZSTD_SKIPPABLEHEADERSIZE; /* magic number + frame length */ - memset(zfhPtr, 0, sizeof(*zfhPtr)); - zfhPtr->frameContentSize = MEM_readLE32((const char *)src + ZSTD_FRAMEIDSIZE); - zfhPtr->frameType = ZSTD_skippableFrame; - return 0; - } - RETURN_ERROR(prefix_unknown); - } - - /* ensure there is enough `srcSize` to fully read/decode frame header */ - { size_t const fhsize = ZSTD_frameHeaderSize_internal(src, srcSize, format); - if (srcSize < fhsize) return fhsize; - zfhPtr->headerSize = (U32)fhsize; - } - - { BYTE const fhdByte = ip[minInputSize-1]; - size_t pos = minInputSize; - U32 const dictIDSizeCode = fhdByte&3; - U32 const checksumFlag = (fhdByte>>2)&1; - U32 const singleSegment = (fhdByte>>5)&1; - U32 const fcsID = fhdByte>>6; - U64 windowSize = 0; - U32 dictID = 0; - U64 frameContentSize = ZSTD_CONTENTSIZE_UNKNOWN; - RETURN_ERROR_IF((fhdByte & 0x08) != 0, frameParameter_unsupported, - "reserved bits, must be zero"); - - if (!singleSegment) { - BYTE const wlByte = ip[pos++]; - U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN; - RETURN_ERROR_IF(windowLog > ZSTD_WINDOWLOG_MAX, frameParameter_windowTooLarge); - windowSize = (1ULL << windowLog); - windowSize += (windowSize >> 3) * (wlByte&7); - } - switch(dictIDSizeCode) - { - default: assert(0); /* impossible */ - case 0 : break; - case 1 : dictID = ip[pos]; pos++; break; - case 2 : dictID = MEM_readLE16(ip+pos); pos+=2; break; - case 3 : dictID = MEM_readLE32(ip+pos); pos+=4; break; - } - switch(fcsID) - { - default: assert(0); /* impossible */ - case 0 : if (singleSegment) frameContentSize = ip[pos]; break; - case 1 : frameContentSize = MEM_readLE16(ip+pos)+256; break; - case 2 : frameContentSize = MEM_readLE32(ip+pos); break; - case 3 : frameContentSize = MEM_readLE64(ip+pos); break; - } - if (singleSegment) windowSize = frameContentSize; - - zfhPtr->frameType = ZSTD_frame; - zfhPtr->frameContentSize = frameContentSize; - zfhPtr->windowSize = windowSize; - zfhPtr->blockSizeMax = (unsigned) MIN(windowSize, ZSTD_BLOCKSIZE_MAX); - zfhPtr->dictID = dictID; - zfhPtr->checksumFlag = checksumFlag; - } - return 0; -} - -/** ZSTD_getFrameHeader() : - * decode Frame Header, or require larger `srcSize`. - * note : this function does not consume input, it only reads it. - * @return : 0, `zfhPtr` is correctly filled, - * >0, `srcSize` is too small, value is wanted `srcSize` amount, - * or an error code, which can be tested using ZSTD_isError() */ -size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize) -{ - return ZSTD_getFrameHeader_advanced(zfhPtr, src, srcSize, ZSTD_f_zstd1); -} - - -/** 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) -{ -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (ZSTD_isLegacy(src, srcSize)) { - unsigned long long const ret = ZSTD_getDecompressedSize_legacy(src, srcSize); - return ret == 0 ? ZSTD_CONTENTSIZE_UNKNOWN : ret; - } -#endif - { ZSTD_frameHeader zfh; - if (ZSTD_getFrameHeader(&zfh, src, srcSize) != 0) - return ZSTD_CONTENTSIZE_ERROR; - if (zfh.frameType == ZSTD_skippableFrame) { - return 0; - } else { - return zfh.frameContentSize; - } } -} - -static size_t readSkippableFrameSize(void const* src, size_t srcSize) -{ - size_t const skippableHeaderSize = ZSTD_SKIPPABLEHEADERSIZE; - U32 sizeU32; - - RETURN_ERROR_IF(srcSize < ZSTD_SKIPPABLEHEADERSIZE, srcSize_wrong); - - sizeU32 = MEM_readLE32((BYTE const*)src + ZSTD_FRAMEIDSIZE); - RETURN_ERROR_IF((U32)(sizeU32 + ZSTD_SKIPPABLEHEADERSIZE) < sizeU32, - frameParameter_unsupported); - - return skippableHeaderSize + sizeU32; -} - -/** 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) { - U32 const magicNumber = MEM_readLE32(src); - - if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { - size_t const skippableSize = readSkippableFrameSize(src, srcSize); - if (ZSTD_isError(skippableSize)) - return skippableSize; - 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; - } - } /* while (srcSize >= ZSTD_frameHeaderSize_prefix) */ - - if (srcSize) return ZSTD_CONTENTSIZE_ERROR; - - return totalDstSize; -} - -/** ZSTD_getDecompressedSize() : - * compatible with legacy mode - * @return : decompressed size if known, 0 otherwise - note : 0 can mean any of the following : - - frame content is empty - - decompressed size field is not present in frame header - - frame header unknown / not supported - - frame header not complete (`srcSize` too small) */ -unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize) -{ - unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize); - ZSTD_STATIC_ASSERT(ZSTD_CONTENTSIZE_ERROR < ZSTD_CONTENTSIZE_UNKNOWN); - return (ret >= ZSTD_CONTENTSIZE_ERROR) ? 0 : ret; -} - - -/** 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_getFrameHeader_advanced(&(dctx->fParams), src, headerSize, dctx->format); - if (ZSTD_isError(result)) return result; /* invalid header */ - RETURN_ERROR_IF(result>0, srcSize_wrong, "headerSize too small"); -#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION - /* Skip the dictID check in fuzzing mode, because it makes the search - * harder. - */ - RETURN_ERROR_IF(dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID), - dictionary_wrong); -#endif - if (dctx->fParams.checksumFlag) XXH64_reset(&dctx->xxhState, 0); - return 0; -} - -static ZSTD_frameSizeInfo ZSTD_errorFrameSizeInfo(size_t ret) -{ - ZSTD_frameSizeInfo frameSizeInfo; - frameSizeInfo.compressedSize = ret; - frameSizeInfo.decompressedBound = ZSTD_CONTENTSIZE_ERROR; - return frameSizeInfo; -} - -static ZSTD_frameSizeInfo ZSTD_findFrameSizeInfo(const void* src, size_t srcSize) -{ - ZSTD_frameSizeInfo frameSizeInfo; - memset(&frameSizeInfo, 0, sizeof(ZSTD_frameSizeInfo)); - -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (ZSTD_isLegacy(src, srcSize)) - return ZSTD_findFrameSizeInfoLegacy(src, srcSize); -#endif - - if ((srcSize >= ZSTD_SKIPPABLEHEADERSIZE) - && (MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { - frameSizeInfo.compressedSize = readSkippableFrameSize(src, srcSize); - return frameSizeInfo; - } else { - const BYTE* ip = (const BYTE*)src; - const BYTE* const ipstart = ip; - size_t remainingSize = srcSize; - size_t nbBlocks = 0; - ZSTD_frameHeader zfh; - - /* Extract Frame Header */ - { size_t const ret = ZSTD_getFrameHeader(&zfh, src, srcSize); - if (ZSTD_isError(ret)) - return ZSTD_errorFrameSizeInfo(ret); - if (ret > 0) - return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong)); - } - - ip += zfh.headerSize; - remainingSize -= zfh.headerSize; - - /* Iterate over each block */ - while (1) { - blockProperties_t blockProperties; - size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); - if (ZSTD_isError(cBlockSize)) - return ZSTD_errorFrameSizeInfo(cBlockSize); - - if (ZSTD_blockHeaderSize + cBlockSize > remainingSize) - return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong)); - - ip += ZSTD_blockHeaderSize + cBlockSize; - remainingSize -= ZSTD_blockHeaderSize + cBlockSize; - nbBlocks++; - - if (blockProperties.lastBlock) break; - } - - /* Final frame content checksum */ - if (zfh.checksumFlag) { - if (remainingSize < 4) - return ZSTD_errorFrameSizeInfo(ERROR(srcSize_wrong)); - ip += 4; - } - - frameSizeInfo.compressedSize = ip - ipstart; - frameSizeInfo.decompressedBound = (zfh.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN) - ? zfh.frameContentSize - : nbBlocks * zfh.blockSizeMax; - return frameSizeInfo; - } -} - -/** 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) -{ - ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize); - return frameSizeInfo.compressedSize; -} - - -/** ZSTD_decompressBound() : - * compatible with legacy mode - * `src` must point to the start of a ZSTD frame or a skippeable frame - * `srcSize` must be at least as large as the frame contained - * @return : the maximum decompressed size of the compressed source - */ -unsigned long long ZSTD_decompressBound(const void* src, size_t srcSize) -{ - unsigned long long bound = 0; - /* Iterate over each frame */ - while (srcSize > 0) { - ZSTD_frameSizeInfo const frameSizeInfo = ZSTD_findFrameSizeInfo(src, srcSize); - size_t const compressedSize = frameSizeInfo.compressedSize; - unsigned long long const decompressedBound = frameSizeInfo.decompressedBound; - if (ZSTD_isError(compressedSize) || decompressedBound == ZSTD_CONTENTSIZE_ERROR) - return ZSTD_CONTENTSIZE_ERROR; - src = (const BYTE*)src + compressedSize; - srcSize -= compressedSize; - bound += decompressedBound; - } - return bound; -} - - -/*-************************************************************* - * Frame decoding - ***************************************************************/ - - -void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst) -{ - if (dst != dctx->previousDstEnd) { /* not contiguous */ - dctx->dictEnd = dctx->previousDstEnd; - dctx->virtualStart = (const char*)dst - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->prefixStart)); - dctx->prefixStart = dst; - dctx->previousDstEnd = dst; - } -} - -/** 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; -} - - -static size_t ZSTD_copyRawBlock(void* dst, size_t dstCapacity, - const void* src, size_t srcSize) -{ - DEBUGLOG(5, "ZSTD_copyRawBlock"); - if (dst == NULL) { - if (srcSize == 0) return 0; - RETURN_ERROR(dstBuffer_null); - } - RETURN_ERROR_IF(srcSize > dstCapacity, dstSize_tooSmall); - memcpy(dst, src, srcSize); - return srcSize; -} - -static size_t ZSTD_setRleBlock(void* dst, size_t dstCapacity, - BYTE b, - size_t regenSize) -{ - if (dst == NULL) { - if (regenSize == 0) return 0; - RETURN_ERROR(dstBuffer_null); - } - RETURN_ERROR_IF(regenSize > dstCapacity, dstSize_tooSmall); - memset(dst, b, regenSize); - return regenSize; -} - - -/*! ZSTD_decompressFrame() : - * @dctx must be properly initialized - * will update *srcPtr and *srcSizePtr, - * to make *srcPtr progress by one frame. */ -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 remainingSrcSize = *srcSizePtr; - - DEBUGLOG(4, "ZSTD_decompressFrame (srcSize:%i)", (int)*srcSizePtr); - - /* check */ - RETURN_ERROR_IF( - remainingSrcSize < ZSTD_FRAMEHEADERSIZE_MIN+ZSTD_blockHeaderSize, - srcSize_wrong); - - /* Frame Header */ - { size_t const frameHeaderSize = ZSTD_frameHeaderSize(ip, ZSTD_FRAMEHEADERSIZE_PREFIX); - if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize; - RETURN_ERROR_IF(remainingSrcSize < frameHeaderSize+ZSTD_blockHeaderSize, - srcSize_wrong); - FORWARD_IF_ERROR( ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize) ); - ip += frameHeaderSize; remainingSrcSize -= frameHeaderSize; - } - - /* Loop on each block */ - while (1) { - size_t decodedSize; - blockProperties_t blockProperties; - size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSrcSize, &blockProperties); - if (ZSTD_isError(cBlockSize)) return cBlockSize; - - ip += ZSTD_blockHeaderSize; - remainingSrcSize -= ZSTD_blockHeaderSize; - RETURN_ERROR_IF(cBlockSize > remainingSrcSize, srcSize_wrong); - - switch(blockProperties.blockType) - { - case bt_compressed: - decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend-op, ip, cBlockSize, /* frame */ 1); - break; - case bt_raw : - decodedSize = ZSTD_copyRawBlock(op, oend-op, ip, cBlockSize); - break; - case bt_rle : - decodedSize = ZSTD_setRleBlock(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; - remainingSrcSize -= cBlockSize; - if (blockProperties.lastBlock) break; - } - - if (dctx->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN) { - RETURN_ERROR_IF((U64)(op-ostart) != dctx->fParams.frameContentSize, - corruption_detected); - } - if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */ - U32 const checkCalc = (U32)XXH64_digest(&dctx->xxhState); - U32 checkRead; - RETURN_ERROR_IF(remainingSrcSize<4, checksum_wrong); - checkRead = MEM_readLE32(ip); - RETURN_ERROR_IF(checkRead != checkCalc, checksum_wrong); - ip += 4; - remainingSrcSize -= 4; - } - - /* Allow caller to get size read */ - *srcPtr = ip; - *srcSizePtr = remainingSrcSize; - return op-ostart; -} - -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; - int moreThan1Frame = 0; - - DEBUGLOG(5, "ZSTD_decompressMultiFrame"); - assert(dict==NULL || ddict==NULL); /* either dict or ddict set, not both */ - - if (ddict) { - dict = ZSTD_DDict_dictContent(ddict); - dictSize = ZSTD_DDict_dictSize(ddict); - } - - while (srcSize >= ZSTD_FRAMEHEADERSIZE_PREFIX) { - -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT >= 1) - if (ZSTD_isLegacy(src, srcSize)) { - size_t decodedSize; - size_t const frameSize = ZSTD_findFrameCompressedSizeLegacy(src, srcSize); - if (ZSTD_isError(frameSize)) return frameSize; - RETURN_ERROR_IF(dctx->staticSize, memory_allocation, - "legacy support is not compatible with static dctx"); - - decodedSize = ZSTD_decompressLegacy(dst, dstCapacity, src, frameSize, dict, dictSize); - if (ZSTD_isError(decodedSize)) return decodedSize; - - assert(decodedSize <=- dstCapacity); - dst = (BYTE*)dst + decodedSize; - dstCapacity -= decodedSize; - - src = (const BYTE*)src + frameSize; - srcSize -= frameSize; - - continue; - } -#endif - - { U32 const magicNumber = MEM_readLE32(src); - DEBUGLOG(4, "reading magic number %08X (expecting %08X)", - (unsigned)magicNumber, ZSTD_MAGICNUMBER); - if ((magicNumber & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { - size_t const skippableSize = readSkippableFrameSize(src, srcSize); - if (ZSTD_isError(skippableSize)) - return skippableSize; - RETURN_ERROR_IF(srcSize < skippableSize, srcSize_wrong); - - src = (const BYTE *)src + skippableSize; - srcSize -= skippableSize; - continue; - } } - - if (ddict) { - /* we were called from ZSTD_decompress_usingDDict */ - FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDDict(dctx, ddict)); - } else { - /* this will initialize correctly with no dict if dict == NULL, so - * use this in all cases but ddict */ - FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize)); - } - ZSTD_checkContinuity(dctx, dst); - - { const size_t res = ZSTD_decompressFrame(dctx, dst, dstCapacity, - &src, &srcSize); - RETURN_ERROR_IF( - (ZSTD_getErrorCode(res) == ZSTD_error_prefix_unknown) - && (moreThan1Frame==1), - srcSize_wrong, - "at least one frame successfully completed, but following " - "bytes are garbage: it's more likely to be a srcSize error, " - "specifying more bytes than compressed size of frame(s). This " - "error message replaces ERROR(prefix_unknown), which would be " - "confusing, as the first header is actually correct. Note that " - "one could be unlucky, it might be a corruption error instead, " - "happening right at the place where we expect zstd magic " - "bytes. But this is _much_ less likely than a srcSize field " - "error."); - if (ZSTD_isError(res)) return res; - assert(res <= dstCapacity); - dst = (BYTE*)dst + res; - dstCapacity -= res; - } - moreThan1Frame = 1; - } /* while (srcSize >= ZSTD_frameHeaderSize_prefix) */ - - RETURN_ERROR_IF(srcSize, 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); -} - - -static ZSTD_DDict const* ZSTD_getDDict(ZSTD_DCtx* dctx) -{ - switch (dctx->dictUses) { - default: - assert(0 /* Impossible */); - /* fall-through */ - case ZSTD_dont_use: - ZSTD_clearDict(dctx); - return NULL; - case ZSTD_use_indefinitely: - return dctx->ddict; - case ZSTD_use_once: - dctx->dictUses = ZSTD_dont_use; - return dctx->ddict; - } -} - -size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize) -{ - return ZSTD_decompress_usingDDict(dctx, dst, dstCapacity, src, srcSize, ZSTD_getDDict(dctx)); -} - - -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(); - RETURN_ERROR_IF(dctx==NULL, memory_allocation); - regenSize = ZSTD_decompressDCtx(dctx, dst, dstCapacity, src, srcSize); - ZSTD_freeDCtx(dctx); - return regenSize; -#else /* stack mode */ - ZSTD_DCtx dctx; - ZSTD_initDCtx_internal(&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 */ - assert(0); - 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; - } -} - -static int ZSTD_isSkipFrame(ZSTD_DCtx* dctx) { return dctx->stage == ZSTDds_skipFrame; } - -/** ZSTD_decompressContinue() : - * srcSize : must be the exact nb of bytes expected (see ZSTD_nextSrcSizeToDecompress()) - * @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) -{ - DEBUGLOG(5, "ZSTD_decompressContinue (srcSize:%u)", (unsigned)srcSize); - /* Sanity check */ - RETURN_ERROR_IF(srcSize != dctx->expected, srcSize_wrong, "not allowed"); - if (dstCapacity) ZSTD_checkContinuity(dctx, dst); - - switch (dctx->stage) - { - case ZSTDds_getFrameHeaderSize : - assert(src != NULL); - if (dctx->format == ZSTD_f_zstd1) { /* allows header */ - assert(srcSize >= ZSTD_FRAMEIDSIZE); /* to read skippable magic number */ - if ((MEM_readLE32(src) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ - memcpy(dctx->headerBuffer, src, srcSize); - dctx->expected = ZSTD_SKIPPABLEHEADERSIZE - srcSize; /* remaining to load to get full skippable frame header */ - dctx->stage = ZSTDds_decodeSkippableHeader; - return 0; - } } - dctx->headerSize = ZSTD_frameHeaderSize_internal(src, srcSize, dctx->format); - if (ZSTD_isError(dctx->headerSize)) return dctx->headerSize; - memcpy(dctx->headerBuffer, src, srcSize); - dctx->expected = dctx->headerSize - srcSize; - dctx->stage = ZSTDds_decodeFrameHeader; - return 0; - - case ZSTDds_decodeFrameHeader: - assert(src != NULL); - memcpy(dctx->headerBuffer + (dctx->headerSize - srcSize), src, srcSize); - FORWARD_IF_ERROR(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 = ZSTD_blockHeaderSize; /* jump to next header */ - dctx->stage = ZSTDds_decodeBlockHeader; - } - return 0; - } - - case ZSTDds_decompressLastBlock: - case ZSTDds_decompressBlock: - DEBUGLOG(5, "ZSTD_decompressContinue: case ZSTDds_decompressBlock"); - { size_t rSize; - switch(dctx->bType) - { - case bt_compressed: - DEBUGLOG(5, "ZSTD_decompressContinue: case bt_compressed"); - rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 1); - break; - case bt_raw : - rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize); - break; - case bt_rle : - rSize = ZSTD_setRleBlock(dst, dstCapacity, *(const BYTE*)src, dctx->rleSize); - break; - case bt_reserved : /* should never happen */ - default: - RETURN_ERROR(corruption_detected); - } - if (ZSTD_isError(rSize)) return rSize; - DEBUGLOG(5, "ZSTD_decompressContinue: decoded size from block : %u", (unsigned)rSize); - dctx->decodedSize += rSize; - if (dctx->fParams.checksumFlag) XXH64_update(&dctx->xxhState, dst, rSize); - - if (dctx->stage == ZSTDds_decompressLastBlock) { /* end of frame */ - DEBUGLOG(4, "ZSTD_decompressContinue: decoded size from frame : %u", (unsigned)dctx->decodedSize); - RETURN_ERROR_IF( - dctx->fParams.frameContentSize != ZSTD_CONTENTSIZE_UNKNOWN - && dctx->decodedSize != dctx->fParams.frameContentSize, - corruption_detected); - 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: - assert(srcSize == 4); /* guaranteed by dctx->expected */ - { U32 const h32 = (U32)XXH64_digest(&dctx->xxhState); - U32 const check32 = MEM_readLE32(src); - DEBUGLOG(4, "ZSTD_decompressContinue: checksum : calculated %08X :: %08X read", (unsigned)h32, (unsigned)check32); - RETURN_ERROR_IF(check32 != h32, checksum_wrong); - dctx->expected = 0; - dctx->stage = ZSTDds_getFrameHeaderSize; - return 0; - } - - case ZSTDds_decodeSkippableHeader: - assert(src != NULL); - assert(srcSize <= ZSTD_SKIPPABLEHEADERSIZE); - memcpy(dctx->headerBuffer + (ZSTD_SKIPPABLEHEADERSIZE - srcSize), src, srcSize); /* complete skippable header */ - dctx->expected = MEM_readLE32(dctx->headerBuffer + ZSTD_FRAMEIDSIZE); /* note : dctx->expected can grow seriously large, beyond local buffer size */ - dctx->stage = ZSTDds_skipFrame; - return 0; - - case ZSTDds_skipFrame: - dctx->expected = 0; - dctx->stage = ZSTDds_getFrameHeaderSize; - return 0; - - default: - assert(0); /* impossible */ - RETURN_ERROR(GENERIC); /* some compiler require default to do something */ - } -} - - -static size_t ZSTD_refDictContent(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) -{ - dctx->dictEnd = dctx->previousDstEnd; - dctx->virtualStart = (const char*)dict - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->prefixStart)); - dctx->prefixStart = dict; - dctx->previousDstEnd = (const char*)dict + dictSize; - return 0; -} - -/*! ZSTD_loadDEntropy() : - * dict : must point at beginning of a valid zstd dictionary. - * @return : size of entropy tables read */ -size_t -ZSTD_loadDEntropy(ZSTD_entropyDTables_t* entropy, - const void* const dict, size_t const dictSize) -{ - const BYTE* dictPtr = (const BYTE*)dict; - const BYTE* const dictEnd = dictPtr + dictSize; - - RETURN_ERROR_IF(dictSize <= 8, dictionary_corrupted); - assert(MEM_readLE32(dict) == ZSTD_MAGIC_DICTIONARY); /* dict must be valid */ - dictPtr += 8; /* skip header = magic + dictID */ - - ZSTD_STATIC_ASSERT(offsetof(ZSTD_entropyDTables_t, OFTable) == offsetof(ZSTD_entropyDTables_t, LLTable) + sizeof(entropy->LLTable)); - ZSTD_STATIC_ASSERT(offsetof(ZSTD_entropyDTables_t, MLTable) == offsetof(ZSTD_entropyDTables_t, OFTable) + sizeof(entropy->OFTable)); - ZSTD_STATIC_ASSERT(sizeof(entropy->LLTable) + sizeof(entropy->OFTable) + sizeof(entropy->MLTable) >= HUF_DECOMPRESS_WORKSPACE_SIZE); - { void* const workspace = &entropy->LLTable; /* use fse tables as temporary workspace; implies fse tables are grouped together */ - size_t const workspaceSize = sizeof(entropy->LLTable) + sizeof(entropy->OFTable) + sizeof(entropy->MLTable); -#ifdef HUF_FORCE_DECOMPRESS_X1 - /* in minimal huffman, we always use X1 variants */ - size_t const hSize = HUF_readDTableX1_wksp(entropy->hufTable, - dictPtr, dictEnd - dictPtr, - workspace, workspaceSize); -#else - size_t const hSize = HUF_readDTableX2_wksp(entropy->hufTable, - dictPtr, dictEnd - dictPtr, - workspace, workspaceSize); -#endif - RETURN_ERROR_IF(HUF_isError(hSize), dictionary_corrupted); - dictPtr += hSize; - } - - { short offcodeNCount[MaxOff+1]; - unsigned offcodeMaxValue = MaxOff, offcodeLog; - size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd-dictPtr); - RETURN_ERROR_IF(FSE_isError(offcodeHeaderSize), dictionary_corrupted); - RETURN_ERROR_IF(offcodeMaxValue > MaxOff, dictionary_corrupted); - RETURN_ERROR_IF(offcodeLog > OffFSELog, dictionary_corrupted); - ZSTD_buildFSETable( entropy->OFTable, - offcodeNCount, offcodeMaxValue, - OF_base, OF_bits, - offcodeLog); - dictPtr += offcodeHeaderSize; - } - - { short matchlengthNCount[MaxML+1]; - unsigned matchlengthMaxValue = MaxML, matchlengthLog; - size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd-dictPtr); - RETURN_ERROR_IF(FSE_isError(matchlengthHeaderSize), dictionary_corrupted); - RETURN_ERROR_IF(matchlengthMaxValue > MaxML, dictionary_corrupted); - RETURN_ERROR_IF(matchlengthLog > MLFSELog, dictionary_corrupted); - ZSTD_buildFSETable( entropy->MLTable, - matchlengthNCount, matchlengthMaxValue, - ML_base, ML_bits, - matchlengthLog); - dictPtr += matchlengthHeaderSize; - } - - { short litlengthNCount[MaxLL+1]; - unsigned litlengthMaxValue = MaxLL, litlengthLog; - size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd-dictPtr); - RETURN_ERROR_IF(FSE_isError(litlengthHeaderSize), dictionary_corrupted); - RETURN_ERROR_IF(litlengthMaxValue > MaxLL, dictionary_corrupted); - RETURN_ERROR_IF(litlengthLog > LLFSELog, dictionary_corrupted); - ZSTD_buildFSETable( entropy->LLTable, - litlengthNCount, litlengthMaxValue, - LL_base, LL_bits, - litlengthLog); - dictPtr += litlengthHeaderSize; - } - - RETURN_ERROR_IF(dictPtr+12 > dictEnd, dictionary_corrupted); - { int i; - size_t const dictContentSize = (size_t)(dictEnd - (dictPtr+12)); - for (i=0; i<3; i++) { - U32 const rep = MEM_readLE32(dictPtr); dictPtr += 4; - RETURN_ERROR_IF(rep==0 || rep >= dictContentSize, - 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 = MEM_readLE32(dict); - if (magic != ZSTD_MAGIC_DICTIONARY) { - return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */ - } } - dctx->dictID = MEM_readLE32((const char*)dict + ZSTD_FRAMEIDSIZE); - - /* load entropy tables */ - { size_t const eSize = ZSTD_loadDEntropy(&dctx->entropy, dict, dictSize); - RETURN_ERROR_IF(ZSTD_isError(eSize), 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(ZSTD_DCtx* dctx) -{ - assert(dctx != NULL); - dctx->expected = ZSTD_startingInputLength(dctx->format); /* dctx->format must be properly set */ - dctx->stage = ZSTDds_getFrameHeaderSize; - dctx->decodedSize = 0; - dctx->previousDstEnd = NULL; - dctx->prefixStart = NULL; - dctx->virtualStart = 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; -} - -size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) -{ - FORWARD_IF_ERROR( ZSTD_decompressBegin(dctx) ); - if (dict && dictSize) - RETURN_ERROR_IF( - ZSTD_isError(ZSTD_decompress_insertDictionary(dctx, dict, dictSize)), - dictionary_corrupted); - return 0; -} - - -/* ====== ZSTD_DDict ====== */ - -size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict) -{ - DEBUGLOG(4, "ZSTD_decompressBegin_usingDDict"); - assert(dctx != NULL); - if (ddict) { - const char* const dictStart = (const char*)ZSTD_DDict_dictContent(ddict); - size_t const dictSize = ZSTD_DDict_dictSize(ddict); - const void* const dictEnd = dictStart + dictSize; - dctx->ddictIsCold = (dctx->dictEnd != dictEnd); - DEBUGLOG(4, "DDict is %s", - dctx->ddictIsCold ? "~cold~" : "hot!"); - } - FORWARD_IF_ERROR( ZSTD_decompressBegin(dctx) ); - if (ddict) { /* NULL ddict is equivalent to no dictionary */ - ZSTD_copyDDictParameters(dctx, ddict); - } - 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 (MEM_readLE32(dict) != ZSTD_MAGIC_DICTIONARY) return 0; - return MEM_readLE32((const char*)dict + ZSTD_FRAMEIDSIZE); -} - -/*! ZSTD_getDictID_fromFrame() : - * Provides the dictID required to decompress 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 (most common case). - * - The frame was built with dictID intentionally removed. - * Needed dictionary is a hidden information. - * Note : this use case also happens when using a non-conformant dictionary. - * - `srcSize` is too small, and as a result, frame header could not be decoded. - * Note : possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`. - * - This is not a Zstandard frame. - * When identifying the exact failure cause, it's possible to use - * ZSTD_getFrameHeader(), which will provide a more precise error code. */ -unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize) -{ - ZSTD_frameHeader zfp = { 0, 0, 0, ZSTD_frame, 0, 0, 0 }; - size_t const hError = ZSTD_getFrameHeader(&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 -*====================================*/ - -ZSTD_DStream* ZSTD_createDStream(void) -{ - DEBUGLOG(3, "ZSTD_createDStream"); - return ZSTD_createDStream_advanced(ZSTD_defaultCMem); -} - -ZSTD_DStream* ZSTD_initStaticDStream(void *workspace, size_t workspaceSize) -{ - return ZSTD_initStaticDCtx(workspace, workspaceSize); -} - -ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem) -{ - return ZSTD_createDCtx_advanced(customMem); -} - -size_t ZSTD_freeDStream(ZSTD_DStream* zds) -{ - return ZSTD_freeDCtx(zds); -} - - -/* *** Initialization *** */ - -size_t ZSTD_DStreamInSize(void) { return ZSTD_BLOCKSIZE_MAX + ZSTD_blockHeaderSize; } -size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_MAX; } - -size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx, - const void* dict, size_t dictSize, - ZSTD_dictLoadMethod_e dictLoadMethod, - ZSTD_dictContentType_e dictContentType) -{ - RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong); - ZSTD_clearDict(dctx); - if (dict && dictSize >= 8) { - dctx->ddictLocal = ZSTD_createDDict_advanced(dict, dictSize, dictLoadMethod, dictContentType, dctx->customMem); - RETURN_ERROR_IF(dctx->ddictLocal == NULL, memory_allocation); - dctx->ddict = dctx->ddictLocal; - dctx->dictUses = ZSTD_use_indefinitely; - } - return 0; -} - -size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) -{ - return ZSTD_DCtx_loadDictionary_advanced(dctx, dict, dictSize, ZSTD_dlm_byRef, ZSTD_dct_auto); -} - -size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize) -{ - return ZSTD_DCtx_loadDictionary_advanced(dctx, dict, dictSize, ZSTD_dlm_byCopy, ZSTD_dct_auto); -} - -size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType) -{ - FORWARD_IF_ERROR(ZSTD_DCtx_loadDictionary_advanced(dctx, prefix, prefixSize, ZSTD_dlm_byRef, dictContentType)); - dctx->dictUses = ZSTD_use_once; - return 0; -} - -size_t ZSTD_DCtx_refPrefix(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize) -{ - return ZSTD_DCtx_refPrefix_advanced(dctx, prefix, prefixSize, ZSTD_dct_rawContent); -} - - -/* ZSTD_initDStream_usingDict() : - * return : expected size, aka ZSTD_FRAMEHEADERSIZE_PREFIX. - * this function cannot fail */ -size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize) -{ - DEBUGLOG(4, "ZSTD_initDStream_usingDict"); - FORWARD_IF_ERROR( ZSTD_DCtx_reset(zds, ZSTD_reset_session_only) ); - FORWARD_IF_ERROR( ZSTD_DCtx_loadDictionary(zds, dict, dictSize) ); - return ZSTD_FRAMEHEADERSIZE_PREFIX; -} - -/* note : this variant can't fail */ -size_t ZSTD_initDStream(ZSTD_DStream* zds) -{ - DEBUGLOG(4, "ZSTD_initDStream"); - return ZSTD_initDStream_usingDDict(zds, NULL); -} - -/* ZSTD_initDStream_usingDDict() : - * ddict will just be referenced, and must outlive decompression session - * this function cannot fail */ -size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* dctx, const ZSTD_DDict* ddict) -{ - FORWARD_IF_ERROR( ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only) ); - FORWARD_IF_ERROR( ZSTD_DCtx_refDDict(dctx, ddict) ); - return ZSTD_FRAMEHEADERSIZE_PREFIX; -} - -/* ZSTD_resetDStream() : - * return : expected size, aka ZSTD_FRAMEHEADERSIZE_PREFIX. - * this function cannot fail */ -size_t ZSTD_resetDStream(ZSTD_DStream* dctx) -{ - FORWARD_IF_ERROR(ZSTD_DCtx_reset(dctx, ZSTD_reset_session_only)); - return ZSTD_FRAMEHEADERSIZE_PREFIX; -} - - -size_t ZSTD_DCtx_refDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict) -{ - RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong); - ZSTD_clearDict(dctx); - if (ddict) { - dctx->ddict = ddict; - dctx->dictUses = ZSTD_use_indefinitely; - } - return 0; -} - -/* ZSTD_DCtx_setMaxWindowSize() : - * note : no direct equivalence in ZSTD_DCtx_setParameter, - * since this version sets windowSize, and the other sets windowLog */ -size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize) -{ - ZSTD_bounds const bounds = ZSTD_dParam_getBounds(ZSTD_d_windowLogMax); - size_t const min = (size_t)1 << bounds.lowerBound; - size_t const max = (size_t)1 << bounds.upperBound; - RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong); - RETURN_ERROR_IF(maxWindowSize < min, parameter_outOfBound); - RETURN_ERROR_IF(maxWindowSize > max, parameter_outOfBound); - dctx->maxWindowSize = maxWindowSize; - return 0; -} - -size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format) -{ - return ZSTD_DCtx_setParameter(dctx, ZSTD_d_format, format); -} - -ZSTD_bounds ZSTD_dParam_getBounds(ZSTD_dParameter dParam) -{ - ZSTD_bounds bounds = { 0, 0, 0 }; - switch(dParam) { - case ZSTD_d_windowLogMax: - bounds.lowerBound = ZSTD_WINDOWLOG_ABSOLUTEMIN; - bounds.upperBound = ZSTD_WINDOWLOG_MAX; - return bounds; - case ZSTD_d_format: - bounds.lowerBound = (int)ZSTD_f_zstd1; - bounds.upperBound = (int)ZSTD_f_zstd1_magicless; - ZSTD_STATIC_ASSERT(ZSTD_f_zstd1 < ZSTD_f_zstd1_magicless); - return bounds; - default:; - } - bounds.error = ERROR(parameter_unsupported); - return bounds; -} - -/* ZSTD_dParam_withinBounds: - * @return 1 if value is within dParam bounds, - * 0 otherwise */ -static int ZSTD_dParam_withinBounds(ZSTD_dParameter dParam, int value) -{ - ZSTD_bounds const bounds = ZSTD_dParam_getBounds(dParam); - if (ZSTD_isError(bounds.error)) return 0; - if (value < bounds.lowerBound) return 0; - if (value > bounds.upperBound) return 0; - return 1; -} - -#define CHECK_DBOUNDS(p,v) { \ - RETURN_ERROR_IF(!ZSTD_dParam_withinBounds(p, v), parameter_outOfBound); \ -} - -size_t ZSTD_DCtx_setParameter(ZSTD_DCtx* dctx, ZSTD_dParameter dParam, int value) -{ - RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong); - switch(dParam) { - case ZSTD_d_windowLogMax: - if (value == 0) value = ZSTD_WINDOWLOG_LIMIT_DEFAULT; - CHECK_DBOUNDS(ZSTD_d_windowLogMax, value); - dctx->maxWindowSize = ((size_t)1) << value; - return 0; - case ZSTD_d_format: - CHECK_DBOUNDS(ZSTD_d_format, value); - dctx->format = (ZSTD_format_e)value; - return 0; - default:; - } - RETURN_ERROR(parameter_unsupported); -} - -size_t ZSTD_DCtx_reset(ZSTD_DCtx* dctx, ZSTD_ResetDirective reset) -{ - if ( (reset == ZSTD_reset_session_only) - || (reset == ZSTD_reset_session_and_parameters) ) { - dctx->streamStage = zdss_init; - dctx->noForwardProgress = 0; - } - if ( (reset == ZSTD_reset_parameters) - || (reset == ZSTD_reset_session_and_parameters) ) { - RETURN_ERROR_IF(dctx->streamStage != zdss_init, stage_wrong); - ZSTD_clearDict(dctx); - dctx->format = ZSTD_f_zstd1; - dctx->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT; - } - return 0; -} - - -size_t ZSTD_sizeof_DStream(const ZSTD_DStream* dctx) -{ - return ZSTD_sizeof_DCtx(dctx); -} - -size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize) -{ - size_t const blockSize = (size_t) MIN(windowSize, ZSTD_BLOCKSIZE_MAX); - unsigned long long const neededRBSize = windowSize + blockSize + (WILDCOPY_OVERLENGTH * 2); - unsigned long long const neededSize = MIN(frameContentSize, neededRBSize); - size_t const minRBSize = (size_t) neededSize; - RETURN_ERROR_IF((unsigned long long)minRBSize != neededSize, - frameParameter_windowTooLarge); - return minRBSize; -} - -size_t ZSTD_estimateDStreamSize(size_t windowSize) -{ - size_t const blockSize = MIN(windowSize, ZSTD_BLOCKSIZE_MAX); - size_t const inBuffSize = blockSize; /* no block can be larger */ - size_t const outBuffSize = ZSTD_decodingBufferSize_min(windowSize, ZSTD_CONTENTSIZE_UNKNOWN); - return ZSTD_estimateDCtxSize() + inBuffSize + outBuffSize; -} - -size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize) -{ - U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX; /* note : should be user-selectable, but requires an additional parameter (or a dctx) */ - ZSTD_frameHeader zfh; - size_t const err = ZSTD_getFrameHeader(&zfh, src, srcSize); - if (ZSTD_isError(err)) return err; - RETURN_ERROR_IF(err>0, srcSize_wrong); - RETURN_ERROR_IF(zfh.windowSize > windowSizeMax, - frameParameter_windowTooLarge); - return ZSTD_estimateDStreamSize((size_t)zfh.windowSize); -} - - -/* ***** 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; - - DEBUGLOG(5, "ZSTD_decompressStream"); - RETURN_ERROR_IF( - input->pos > input->size, - srcSize_wrong, - "forbidden. in: pos: %u vs size: %u", - (U32)input->pos, (U32)input->size); - RETURN_ERROR_IF( - output->pos > output->size, - dstSize_tooSmall, - "forbidden. out: pos: %u vs size: %u", - (U32)output->pos, (U32)output->size); - DEBUGLOG(5, "input size : %u", (U32)(input->size - input->pos)); - - while (someMoreWork) { - switch(zds->streamStage) - { - case zdss_init : - DEBUGLOG(5, "stage zdss_init => transparent reset "); - zds->streamStage = zdss_loadHeader; - zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; - zds->legacyVersion = 0; - zds->hostageByte = 0; - /* fall-through */ - - case zdss_loadHeader : - DEBUGLOG(5, "stage zdss_loadHeader (srcSize : %u)", (U32)(iend - ip)); -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) - if (zds->legacyVersion) { - RETURN_ERROR_IF(zds->staticSize, memory_allocation, - "legacy support is incompatible with static dctx"); - { size_t const hint = ZSTD_decompressLegacyStream(zds->legacyContext, zds->legacyVersion, output, input); - if (hint==0) zds->streamStage = zdss_init; - return hint; - } } -#endif - { size_t const hSize = ZSTD_getFrameHeader_advanced(&zds->fParams, zds->headerBuffer, zds->lhSize, zds->format); - DEBUGLOG(5, "header size : %u", (U32)hSize); - if (ZSTD_isError(hSize)) { -#if defined(ZSTD_LEGACY_SUPPORT) && (ZSTD_LEGACY_SUPPORT>=1) - U32 const legacyVersion = ZSTD_isLegacy(istart, iend-istart); - if (legacyVersion) { - ZSTD_DDict const* const ddict = ZSTD_getDDict(zds); - const void* const dict = ddict ? ZSTD_DDict_dictContent(ddict) : NULL; - size_t const dictSize = ddict ? ZSTD_DDict_dictSize(ddict) : 0; - DEBUGLOG(5, "ZSTD_decompressStream: detected legacy version v0.%u", legacyVersion); - RETURN_ERROR_IF(zds->staticSize, memory_allocation, - "legacy support is incompatible with static dctx"); - FORWARD_IF_ERROR(ZSTD_initLegacyStream(&zds->legacyContext, - zds->previousLegacyVersion, legacyVersion, - dict, dictSize)); - zds->legacyVersion = zds->previousLegacyVersion = legacyVersion; - { size_t const hint = ZSTD_decompressLegacyStream(zds->legacyContext, legacyVersion, output, input); - if (hint==0) zds->streamStage = zdss_init; /* or stay in stage zdss_loadHeader */ - return hint; - } } -#endif - return hSize; /* error */ - } - if (hSize != 0) { /* need more input */ - size_t const toLoad = hSize - zds->lhSize; /* if hSize!=0, hSize > zds->lhSize */ - size_t const remainingInput = (size_t)(iend-ip); - assert(iend >= ip); - if (toLoad > remainingInput) { /* not enough input to load full header */ - if (remainingInput > 0) { - memcpy(zds->headerBuffer + zds->lhSize, ip, remainingInput); - zds->lhSize += remainingInput; - } - input->pos = input->size; - return (MAX(ZSTD_FRAMEHEADERSIZE_MIN, hSize) - zds->lhSize) + ZSTD_blockHeaderSize; /* remaining header bytes + next block header */ - } - assert(ip != NULL); - 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)) { - /* shortcut : using single-pass mode */ - size_t const decompressedSize = ZSTD_decompress_usingDDict(zds, op, oend-op, istart, cSize, ZSTD_getDDict(zds)); - if (ZSTD_isError(decompressedSize)) return decompressedSize; - DEBUGLOG(4, "shortcut to single-pass ZSTD_decompress_usingDDict()") - ip = istart + cSize; - op += decompressedSize; - zds->expected = 0; - zds->streamStage = zdss_init; - someMoreWork = 0; - break; - } } - - /* Consume header (see ZSTDds_decodeFrameHeader) */ - DEBUGLOG(4, "Consume header"); - FORWARD_IF_ERROR(ZSTD_decompressBegin_usingDDict(zds, ZSTD_getDDict(zds))); - - if ((MEM_readLE32(zds->headerBuffer) & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ - zds->expected = MEM_readLE32(zds->headerBuffer + ZSTD_FRAMEIDSIZE); - zds->stage = ZSTDds_skipFrame; - } else { - FORWARD_IF_ERROR(ZSTD_decodeFrameHeader(zds, zds->headerBuffer, zds->lhSize)); - zds->expected = ZSTD_blockHeaderSize; - zds->stage = ZSTDds_decodeBlockHeader; - } - - /* control buffer memory usage */ - DEBUGLOG(4, "Control max memory usage (%u KB <= max %u KB)", - (U32)(zds->fParams.windowSize >>10), - (U32)(zds->maxWindowSize >> 10) ); - zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN); - RETURN_ERROR_IF(zds->fParams.windowSize > zds->maxWindowSize, - frameParameter_windowTooLarge); - - /* Adapt buffer sizes to frame header instructions */ - { size_t const neededInBuffSize = MAX(zds->fParams.blockSizeMax, 4 /* frame checksum */); - size_t const neededOutBuffSize = ZSTD_decodingBufferSize_min(zds->fParams.windowSize, zds->fParams.frameContentSize); - if ((zds->inBuffSize < neededInBuffSize) || (zds->outBuffSize < neededOutBuffSize)) { - size_t const bufferSize = neededInBuffSize + neededOutBuffSize; - DEBUGLOG(4, "inBuff : from %u to %u", - (U32)zds->inBuffSize, (U32)neededInBuffSize); - DEBUGLOG(4, "outBuff : from %u to %u", - (U32)zds->outBuffSize, (U32)neededOutBuffSize); - if (zds->staticSize) { /* static DCtx */ - DEBUGLOG(4, "staticSize : %u", (U32)zds->staticSize); - assert(zds->staticSize >= sizeof(ZSTD_DCtx)); /* controlled at init */ - RETURN_ERROR_IF( - bufferSize > zds->staticSize - sizeof(ZSTD_DCtx), - memory_allocation); - } else { - ZSTD_free(zds->inBuff, zds->customMem); - zds->inBuffSize = 0; - zds->outBuffSize = 0; - zds->inBuff = (char*)ZSTD_malloc(bufferSize, zds->customMem); - RETURN_ERROR_IF(zds->inBuff == NULL, memory_allocation); - } - zds->inBuffSize = neededInBuffSize; - zds->outBuff = zds->inBuff + zds->inBuffSize; - zds->outBuffSize = neededOutBuffSize; - } } - zds->streamStage = zdss_read; - /* fall-through */ - - case zdss_read: - DEBUGLOG(5, "stage zdss_read"); - { size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds); - DEBUGLOG(5, "neededInSize = %u", (U32)neededInSize); - if (neededInSize==0) { /* end of frame */ - zds->streamStage = zdss_init; - someMoreWork = 0; - break; - } - if ((size_t)(iend-ip) >= neededInSize) { /* decode directly from src */ - int const isSkipFrame = ZSTD_isSkipFrame(zds); - size_t const decodedSize = ZSTD_decompressContinue(zds, - 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->streamStage = zdss_flush; - break; - } } - if (ip==iend) { someMoreWork = 0; break; } /* no more input */ - zds->streamStage = zdss_load; - /* fall-through */ - - case zdss_load: - { size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds); - size_t const toLoad = neededInSize - zds->inPos; - int const isSkipFrame = ZSTD_isSkipFrame(zds); - size_t loadedSize; - if (isSkipFrame) { - loadedSize = MIN(toLoad, (size_t)(iend-ip)); - } else { - RETURN_ERROR_IF(toLoad > zds->inBuffSize - zds->inPos, - 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 */ - { size_t const decodedSize = ZSTD_decompressContinue(zds, - 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->streamStage = zdss_read; break; } /* this was just a header */ - zds->outEnd = zds->outStart + decodedSize; - } } - zds->streamStage = zdss_flush; - /* fall-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->streamStage = zdss_read; - if ( (zds->outBuffSize < zds->fParams.frameContentSize) - && (zds->outStart + zds->fParams.blockSizeMax > zds->outBuffSize) ) { - DEBUGLOG(5, "restart filling outBuff from beginning (left:%i, needed:%u)", - (int)(zds->outBuffSize - zds->outStart), - (U32)zds->fParams.blockSizeMax); - zds->outStart = zds->outEnd = 0; - } - break; - } } - /* cannot complete flush */ - someMoreWork = 0; - break; - - default: - assert(0); /* impossible */ - RETURN_ERROR(GENERIC); /* some compiler require default to do something */ - } } - - /* result */ - input->pos = (size_t)(ip - (const char*)(input->src)); - output->pos = (size_t)(op - (char*)(output->dst)); - if ((ip==istart) && (op==ostart)) { /* no forward progress */ - zds->noForwardProgress ++; - if (zds->noForwardProgress >= ZSTD_NO_FORWARD_PROGRESS_MAX) { - RETURN_ERROR_IF(op==oend, dstSize_tooSmall); - RETURN_ERROR_IF(ip==iend, srcSize_wrong); - assert(0); - } - } else { - zds->noForwardProgress = 0; - } - { size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds); - if (!nextSrcSizeHint) { /* frame fully decoded */ - if (zds->outEnd == zds->outStart) { /* output fully flushed */ - if (zds->hostageByte) { - if (input->pos >= input->size) { - /* can't release hostage (not present) */ - zds->streamStage = zdss_read; - return 1; - } - input->pos++; /* release hostage */ - } /* zds->hostageByte */ - return 0; - } /* zds->outEnd == zds->outStart */ - 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==0 */ - nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds) == ZSTDnit_block); /* preload header of next block */ - assert(zds->inPos <= nextSrcSizeHint); - nextSrcSizeHint -= zds->inPos; /* part already loaded*/ - return nextSrcSizeHint; - } -} - -size_t ZSTD_decompressStream_simpleArgs ( - ZSTD_DCtx* dctx, - void* dst, size_t dstCapacity, size_t* dstPos, - const void* src, size_t srcSize, size_t* srcPos) -{ - ZSTD_outBuffer output = { dst, dstCapacity, *dstPos }; - ZSTD_inBuffer input = { src, srcSize, *srcPos }; - /* ZSTD_compress_generic() will check validity of dstPos and srcPos */ - size_t const cErr = ZSTD_decompressStream(dctx, &output, &input); - *dstPos = output.pos; - *srcPos = input.pos; - return cErr; -} |