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-rw-r--r--lib/zstd/decompress.c2531
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");