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");