v4.19.13 snapshot.
diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
new file mode 100644
index 0000000..b178467
--- /dev/null
+++ b/lib/zstd/decompress.c
@@ -0,0 +1,2528 @@
+/**
+ * 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);
+ /* fall-through */
+ 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 */
+
+ 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 */
+ /* fall-through */
+
+ 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;
+ }
+ /* pass-through */
+
+ 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 */
+ }
+
+ 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 */
+ }
+ }
+
+ 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");