[PATCH 3/4] lib: Add zstd modules
Philipp Zabel
p.zabel at pengutronix.de
Thu Feb 1 02:46:14 PST 2018
Based on kernel commit 73f3d1b48f50 ("lib: Add zstd modules").
Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
---
include/linux/zstd.h | 1157 +++++++++++++++++++++
lib/Kconfig | 5 +
lib/Makefile | 1 +
lib/zstd/Makefile | 6 +
lib/zstd/bitstream.h | 374 +++++++
lib/zstd/decompress.c | 2528 +++++++++++++++++++++++++++++++++++++++++++++
lib/zstd/entropy_common.c | 243 +++++
lib/zstd/error_private.h | 53 +
lib/zstd/fse.h | 575 +++++++++++
lib/zstd/fse_decompress.c | 332 ++++++
lib/zstd/huf.h | 212 ++++
lib/zstd/huf_decompress.c | 960 +++++++++++++++++
lib/zstd/mem.h | 151 +++
lib/zstd/zstd_common.c | 75 ++
lib/zstd/zstd_internal.h | 263 +++++
lib/zstd/zstd_opt.h | 1014 ++++++++++++++++++
16 files changed, 7949 insertions(+)
create mode 100644 include/linux/zstd.h
create mode 100644 lib/zstd/Makefile
create mode 100644 lib/zstd/bitstream.h
create mode 100644 lib/zstd/decompress.c
create mode 100644 lib/zstd/entropy_common.c
create mode 100644 lib/zstd/error_private.h
create mode 100644 lib/zstd/fse.h
create mode 100644 lib/zstd/fse_decompress.c
create mode 100644 lib/zstd/huf.h
create mode 100644 lib/zstd/huf_decompress.c
create mode 100644 lib/zstd/mem.h
create mode 100644 lib/zstd/zstd_common.c
create mode 100644 lib/zstd/zstd_internal.h
create mode 100644 lib/zstd/zstd_opt.h
diff --git a/include/linux/zstd.h b/include/linux/zstd.h
new file mode 100644
index 0000000000..249575e248
--- /dev/null
+++ b/include/linux/zstd.h
@@ -0,0 +1,1157 @@
+/*
+ * 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").
+ */
+
+#ifndef ZSTD_H
+#define ZSTD_H
+
+/* ====== Dependency ======*/
+#include <linux/types.h> /* size_t */
+
+
+/*-*****************************************************************************
+ * Introduction
+ *
+ * zstd, short for Zstandard, is a fast lossless compression algorithm,
+ * targeting real-time compression scenarios at zlib-level and better
+ * compression ratios. The zstd compression library provides in-memory
+ * compression and decompression functions. The library supports compression
+ * levels from 1 up to ZSTD_maxCLevel() which is 22. Levels >= 20, labeled
+ * ultra, should be used with caution, as they require more memory.
+ * Compression can be done in:
+ * - a single step, reusing a context (described as Explicit memory management)
+ * - unbounded multiple steps (described as Streaming compression)
+ * The compression ratio achievable on small data can be highly improved using
+ * compression with a dictionary in:
+ * - a single step (described as Simple dictionary API)
+ * - a single step, reusing a dictionary (described as Fast dictionary API)
+ ******************************************************************************/
+
+/*====== Helper functions ======*/
+
+/**
+ * enum ZSTD_ErrorCode - zstd error codes
+ *
+ * Functions that return size_t can be checked for errors using ZSTD_isError()
+ * and the ZSTD_ErrorCode can be extracted using ZSTD_getErrorCode().
+ */
+typedef enum {
+ ZSTD_error_no_error,
+ ZSTD_error_GENERIC,
+ ZSTD_error_prefix_unknown,
+ ZSTD_error_version_unsupported,
+ ZSTD_error_parameter_unknown,
+ ZSTD_error_frameParameter_unsupported,
+ ZSTD_error_frameParameter_unsupportedBy32bits,
+ ZSTD_error_frameParameter_windowTooLarge,
+ ZSTD_error_compressionParameter_unsupported,
+ ZSTD_error_init_missing,
+ ZSTD_error_memory_allocation,
+ ZSTD_error_stage_wrong,
+ ZSTD_error_dstSize_tooSmall,
+ ZSTD_error_srcSize_wrong,
+ ZSTD_error_corruption_detected,
+ ZSTD_error_checksum_wrong,
+ ZSTD_error_tableLog_tooLarge,
+ ZSTD_error_maxSymbolValue_tooLarge,
+ ZSTD_error_maxSymbolValue_tooSmall,
+ ZSTD_error_dictionary_corrupted,
+ ZSTD_error_dictionary_wrong,
+ ZSTD_error_dictionaryCreation_failed,
+ ZSTD_error_maxCode
+} ZSTD_ErrorCode;
+
+/**
+ * ZSTD_maxCLevel() - maximum compression level available
+ *
+ * Return: Maximum compression level available.
+ */
+int ZSTD_maxCLevel(void);
+/**
+ * ZSTD_compressBound() - maximum compressed size in worst case scenario
+ * @srcSize: The size of the data to compress.
+ *
+ * Return: The maximum compressed size in the worst case scenario.
+ */
+size_t ZSTD_compressBound(size_t srcSize);
+/**
+ * ZSTD_isError() - tells if a size_t function result is an error code
+ * @code: The function result to check for error.
+ *
+ * Return: Non-zero iff the code is an error.
+ */
+static __attribute__((unused)) unsigned int ZSTD_isError(size_t code)
+{
+ return code > (size_t)-ZSTD_error_maxCode;
+}
+/**
+ * ZSTD_getErrorCode() - translates an error function result to a ZSTD_ErrorCode
+ * @functionResult: The result of a function for which ZSTD_isError() is true.
+ *
+ * Return: The ZSTD_ErrorCode corresponding to the functionResult or 0
+ * if the functionResult isn't an error.
+ */
+static __attribute__((unused)) ZSTD_ErrorCode ZSTD_getErrorCode(
+ size_t functionResult)
+{
+ if (!ZSTD_isError(functionResult))
+ return (ZSTD_ErrorCode)0;
+ return (ZSTD_ErrorCode)(0 - functionResult);
+}
+
+/**
+ * enum ZSTD_strategy - zstd compression search strategy
+ *
+ * From faster to stronger.
+ */
+typedef enum {
+ ZSTD_fast,
+ ZSTD_dfast,
+ ZSTD_greedy,
+ ZSTD_lazy,
+ ZSTD_lazy2,
+ ZSTD_btlazy2,
+ ZSTD_btopt,
+ ZSTD_btopt2
+} ZSTD_strategy;
+
+/**
+ * struct ZSTD_compressionParameters - zstd compression parameters
+ * @windowLog: Log of the largest match distance. Larger means more
+ * compression, and more memory needed during decompression.
+ * @chainLog: Fully searched segment. Larger means more compression, slower,
+ * and more memory (useless for fast).
+ * @hashLog: Dispatch table. Larger means more compression,
+ * slower, and more memory.
+ * @searchLog: Number of searches. Larger means more compression and slower.
+ * @searchLength: Match length searched. Larger means faster decompression,
+ * sometimes less compression.
+ * @targetLength: Acceptable match size for optimal parser (only). Larger means
+ * more compression, and slower.
+ * @strategy: The zstd compression strategy.
+ */
+typedef struct {
+ unsigned int windowLog;
+ unsigned int chainLog;
+ unsigned int hashLog;
+ unsigned int searchLog;
+ unsigned int searchLength;
+ unsigned int targetLength;
+ ZSTD_strategy strategy;
+} ZSTD_compressionParameters;
+
+/**
+ * struct ZSTD_frameParameters - zstd frame parameters
+ * @contentSizeFlag: Controls whether content size will be present in the frame
+ * header (when known).
+ * @checksumFlag: Controls whether a 32-bit checksum is generated at the end
+ * of the frame for error detection.
+ * @noDictIDFlag: Controls whether dictID will be saved into the frame header
+ * when using dictionary compression.
+ *
+ * The default value is all fields set to 0.
+ */
+typedef struct {
+ unsigned int contentSizeFlag;
+ unsigned int checksumFlag;
+ unsigned int noDictIDFlag;
+} ZSTD_frameParameters;
+
+/**
+ * struct ZSTD_parameters - zstd parameters
+ * @cParams: The compression parameters.
+ * @fParams: The frame parameters.
+ */
+typedef struct {
+ ZSTD_compressionParameters cParams;
+ ZSTD_frameParameters fParams;
+} ZSTD_parameters;
+
+/**
+ * ZSTD_getCParams() - returns ZSTD_compressionParameters for selected level
+ * @compressionLevel: The compression level from 1 to ZSTD_maxCLevel().
+ * @estimatedSrcSize: The estimated source size to compress or 0 if unknown.
+ * @dictSize: The dictionary size or 0 if a dictionary isn't being used.
+ *
+ * Return: The selected ZSTD_compressionParameters.
+ */
+ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel,
+ unsigned long long estimatedSrcSize, size_t dictSize);
+
+/**
+ * ZSTD_getParams() - returns ZSTD_parameters for selected level
+ * @compressionLevel: The compression level from 1 to ZSTD_maxCLevel().
+ * @estimatedSrcSize: The estimated source size to compress or 0 if unknown.
+ * @dictSize: The dictionary size or 0 if a dictionary isn't being used.
+ *
+ * The same as ZSTD_getCParams() except also selects the default frame
+ * parameters (all zero).
+ *
+ * Return: The selected ZSTD_parameters.
+ */
+ZSTD_parameters ZSTD_getParams(int compressionLevel,
+ unsigned long long estimatedSrcSize, size_t dictSize);
+
+/*-*************************************
+ * Explicit memory management
+ **************************************/
+
+/**
+ * ZSTD_CCtxWorkspaceBound() - amount of memory needed to initialize a ZSTD_CCtx
+ * @cParams: The compression parameters to be used for compression.
+ *
+ * If multiple compression parameters might be used, the caller must call
+ * ZSTD_CCtxWorkspaceBound() for each set of parameters and use the maximum
+ * size.
+ *
+ * Return: A lower bound on the size of the workspace that is passed to
+ * ZSTD_initCCtx().
+ */
+size_t ZSTD_CCtxWorkspaceBound(ZSTD_compressionParameters cParams);
+
+/**
+ * struct ZSTD_CCtx - the zstd compression context
+ *
+ * When compressing many times it is recommended to allocate a context just once
+ * and reuse it for each successive compression operation.
+ */
+typedef struct ZSTD_CCtx_s ZSTD_CCtx;
+/**
+ * ZSTD_initCCtx() - initialize a zstd compression context
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace. Use ZSTD_CCtxWorkspaceBound() to
+ * determine how large the workspace must be.
+ *
+ * Return: A compression context emplaced into workspace.
+ */
+ZSTD_CCtx *ZSTD_initCCtx(void *workspace, size_t workspaceSize);
+
+/**
+ * ZSTD_compressCCtx() - compress src into dst
+ * @ctx: The context. Must have been initialized with a workspace at
+ * least as large as ZSTD_CCtxWorkspaceBound(params.cParams).
+ * @dst: The buffer to compress src into.
+ * @dstCapacity: The size of the destination buffer. May be any size, but
+ * ZSTD_compressBound(srcSize) is guaranteed to be large enough.
+ * @src: The data to compress.
+ * @srcSize: The size of the data to compress.
+ * @params: The parameters to use for compression. See ZSTD_getParams().
+ *
+ * Return: The compressed size or an error, which can be checked using
+ * ZSTD_isError().
+ */
+size_t ZSTD_compressCCtx(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize, ZSTD_parameters params);
+
+/**
+ * ZSTD_DCtxWorkspaceBound() - amount of memory needed to initialize a ZSTD_DCtx
+ *
+ * Return: A lower bound on the size of the workspace that is passed to
+ * ZSTD_initDCtx().
+ */
+size_t ZSTD_DCtxWorkspaceBound(void);
+
+/**
+ * struct ZSTD_DCtx - the zstd decompression context
+ *
+ * When decompressing many times it is recommended to allocate a context just
+ * once and reuse it for each successive decompression operation.
+ */
+typedef struct ZSTD_DCtx_s ZSTD_DCtx;
+/**
+ * ZSTD_initDCtx() - initialize a zstd decompression context
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace. Use ZSTD_DCtxWorkspaceBound() to
+ * determine how large the workspace must be.
+ *
+ * Return: A decompression context emplaced into workspace.
+ */
+ZSTD_DCtx *ZSTD_initDCtx(void *workspace, size_t workspaceSize);
+
+/**
+ * ZSTD_decompressDCtx() - decompress zstd compressed src into dst
+ * @ctx: The decompression context.
+ * @dst: The buffer to decompress src into.
+ * @dstCapacity: The size of the destination buffer. Must be at least as large
+ * as the decompressed size. If the caller cannot upper bound the
+ * decompressed size, then it's better to use the streaming API.
+ * @src: The zstd compressed data to decompress. Multiple concatenated
+ * frames and skippable frames are allowed.
+ * @srcSize: The exact size of the data to decompress.
+ *
+ * Return: The decompressed size or an error, which can be checked using
+ * ZSTD_isError().
+ */
+size_t ZSTD_decompressDCtx(ZSTD_DCtx *ctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+
+/*-************************
+ * Simple dictionary API
+ **************************/
+
+/**
+ * ZSTD_compress_usingDict() - compress src into dst using a dictionary
+ * @ctx: The context. Must have been initialized with a workspace at
+ * least as large as ZSTD_CCtxWorkspaceBound(params.cParams).
+ * @dst: The buffer to compress src into.
+ * @dstCapacity: The size of the destination buffer. May be any size, but
+ * ZSTD_compressBound(srcSize) is guaranteed to be large enough.
+ * @src: The data to compress.
+ * @srcSize: The size of the data to compress.
+ * @dict: The dictionary to use for compression.
+ * @dictSize: The size of the dictionary.
+ * @params: The parameters to use for compression. See ZSTD_getParams().
+ *
+ * Compression using a predefined dictionary. The same dictionary must be used
+ * during decompression.
+ *
+ * Return: The compressed size or an error, which can be checked using
+ * ZSTD_isError().
+ */
+size_t ZSTD_compress_usingDict(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize, const void *dict, size_t dictSize,
+ ZSTD_parameters params);
+
+/**
+ * ZSTD_decompress_usingDict() - decompress src into dst using a dictionary
+ * @ctx: The decompression context.
+ * @dst: The buffer to decompress src into.
+ * @dstCapacity: The size of the destination buffer. Must be at least as large
+ * as the decompressed size. If the caller cannot upper bound the
+ * decompressed size, then it's better to use the streaming API.
+ * @src: The zstd compressed data to decompress. Multiple concatenated
+ * frames and skippable frames are allowed.
+ * @srcSize: The exact size of the data to decompress.
+ * @dict: The dictionary to use for decompression. The same dictionary
+ * must've been used to compress the data.
+ * @dictSize: The size of the dictionary.
+ *
+ * Return: The decompressed size or an error, which can be checked using
+ * ZSTD_isError().
+ */
+size_t ZSTD_decompress_usingDict(ZSTD_DCtx *ctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize, const void *dict, size_t dictSize);
+
+/*-**************************
+ * Fast dictionary API
+ ***************************/
+
+/**
+ * ZSTD_CDictWorkspaceBound() - memory needed to initialize a ZSTD_CDict
+ * @cParams: The compression parameters to be used for compression.
+ *
+ * Return: A lower bound on the size of the workspace that is passed to
+ * ZSTD_initCDict().
+ */
+size_t ZSTD_CDictWorkspaceBound(ZSTD_compressionParameters cParams);
+
+/**
+ * struct ZSTD_CDict - a digested dictionary to be used for compression
+ */
+typedef struct ZSTD_CDict_s ZSTD_CDict;
+
+/**
+ * ZSTD_initCDict() - initialize a digested dictionary for compression
+ * @dictBuffer: The dictionary to digest. The buffer is referenced by the
+ * ZSTD_CDict so it must outlive the returned ZSTD_CDict.
+ * @dictSize: The size of the dictionary.
+ * @params: The parameters to use for compression. See ZSTD_getParams().
+ * @workspace: The workspace. It must outlive the returned ZSTD_CDict.
+ * @workspaceSize: The workspace size. Must be at least
+ * ZSTD_CDictWorkspaceBound(params.cParams).
+ *
+ * When compressing multiple messages / blocks with the same dictionary it is
+ * recommended to load it just once. The ZSTD_CDict merely references the
+ * dictBuffer, so it must outlive the returned ZSTD_CDict.
+ *
+ * Return: The digested dictionary emplaced into workspace.
+ */
+ZSTD_CDict *ZSTD_initCDict(const void *dictBuffer, size_t dictSize,
+ ZSTD_parameters params, void *workspace, size_t workspaceSize);
+
+/**
+ * ZSTD_compress_usingCDict() - compress src into dst using a ZSTD_CDict
+ * @ctx: The context. Must have been initialized with a workspace at
+ * least as large as ZSTD_CCtxWorkspaceBound(cParams) where
+ * cParams are the compression parameters used to initialize the
+ * cdict.
+ * @dst: The buffer to compress src into.
+ * @dstCapacity: The size of the destination buffer. May be any size, but
+ * ZSTD_compressBound(srcSize) is guaranteed to be large enough.
+ * @src: The data to compress.
+ * @srcSize: The size of the data to compress.
+ * @cdict: The digested dictionary to use for compression.
+ * @params: The parameters to use for compression. See ZSTD_getParams().
+ *
+ * Compression using a digested dictionary. The same dictionary must be used
+ * during decompression.
+ *
+ * Return: The compressed size or an error, which can be checked using
+ * ZSTD_isError().
+ */
+size_t ZSTD_compress_usingCDict(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize, const ZSTD_CDict *cdict);
+
+
+/**
+ * ZSTD_DDictWorkspaceBound() - memory needed to initialize a ZSTD_DDict
+ *
+ * Return: A lower bound on the size of the workspace that is passed to
+ * ZSTD_initDDict().
+ */
+size_t ZSTD_DDictWorkspaceBound(void);
+
+/**
+ * struct ZSTD_DDict - a digested dictionary to be used for decompression
+ */
+typedef struct ZSTD_DDict_s ZSTD_DDict;
+
+/**
+ * ZSTD_initDDict() - initialize a digested dictionary for decompression
+ * @dictBuffer: The dictionary to digest. The buffer is referenced by the
+ * ZSTD_DDict so it must outlive the returned ZSTD_DDict.
+ * @dictSize: The size of the dictionary.
+ * @workspace: The workspace. It must outlive the returned ZSTD_DDict.
+ * @workspaceSize: The workspace size. Must be at least
+ * ZSTD_DDictWorkspaceBound().
+ *
+ * When decompressing multiple messages / blocks with the same dictionary it is
+ * recommended to load it just once. The ZSTD_DDict merely references the
+ * dictBuffer, so it must outlive the returned ZSTD_DDict.
+ *
+ * Return: The digested dictionary emplaced into workspace.
+ */
+ZSTD_DDict *ZSTD_initDDict(const void *dictBuffer, size_t dictSize,
+ void *workspace, size_t workspaceSize);
+
+/**
+ * ZSTD_decompress_usingDDict() - decompress src into dst using a ZSTD_DDict
+ * @ctx: The decompression context.
+ * @dst: The buffer to decompress src into.
+ * @dstCapacity: The size of the destination buffer. Must be at least as large
+ * as the decompressed size. If the caller cannot upper bound the
+ * decompressed size, then it's better to use the streaming API.
+ * @src: The zstd compressed data to decompress. Multiple concatenated
+ * frames and skippable frames are allowed.
+ * @srcSize: The exact size of the data to decompress.
+ * @ddict: The digested dictionary to use for decompression. The same
+ * dictionary must've been used to compress the data.
+ *
+ * Return: The decompressed size or an error, which can be checked using
+ * ZSTD_isError().
+ */
+size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst,
+ size_t dstCapacity, const void *src, size_t srcSize,
+ const ZSTD_DDict *ddict);
+
+
+/*-**************************
+ * Streaming
+ ***************************/
+
+/**
+ * struct ZSTD_inBuffer - input buffer for streaming
+ * @src: Start of the input buffer.
+ * @size: Size of the input buffer.
+ * @pos: Position where reading stopped. Will be updated.
+ * Necessarily 0 <= pos <= size.
+ */
+typedef struct ZSTD_inBuffer_s {
+ const void *src;
+ size_t size;
+ size_t pos;
+} ZSTD_inBuffer;
+
+/**
+ * struct ZSTD_outBuffer - output buffer for streaming
+ * @dst: Start of the output buffer.
+ * @size: Size of the output buffer.
+ * @pos: Position where writing stopped. Will be updated.
+ * Necessarily 0 <= pos <= size.
+ */
+typedef struct ZSTD_outBuffer_s {
+ void *dst;
+ size_t size;
+ size_t pos;
+} ZSTD_outBuffer;
+
+
+
+/*-*****************************************************************************
+ * Streaming compression - HowTo
+ *
+ * A ZSTD_CStream object is required to track streaming operation.
+ * Use ZSTD_initCStream() to initialize a ZSTD_CStream object.
+ * ZSTD_CStream objects can be reused multiple times on consecutive compression
+ * operations. It is recommended to re-use ZSTD_CStream in situations where many
+ * streaming operations will be achieved consecutively. Use one separate
+ * ZSTD_CStream per thread for parallel execution.
+ *
+ * Use ZSTD_compressStream() repetitively to consume input stream.
+ * The function will automatically update both `pos` fields.
+ * Note that it may not consume the entire input, in which case `pos < size`,
+ * and it's up to the caller to present again remaining data.
+ * It returns a hint for the preferred number of bytes to use as an input for
+ * the next function call.
+ *
+ * At any moment, it's possible to flush whatever data remains within internal
+ * buffer, using ZSTD_flushStream(). `output->pos` will be updated. There might
+ * still be some content left within the internal buffer if `output->size` is
+ * too small. It returns the number of bytes left in the internal buffer and
+ * must be called until it returns 0.
+ *
+ * ZSTD_endStream() instructs to finish a frame. It will perform a flush and
+ * write frame epilogue. The epilogue is required for decoders to consider a
+ * frame completed. Similar to ZSTD_flushStream(), it may not be able to flush
+ * the full content if `output->size` is too small. In which case, call again
+ * ZSTD_endStream() to complete the flush. It returns the number of bytes left
+ * in the internal buffer and must be called until it returns 0.
+ ******************************************************************************/
+
+/**
+ * ZSTD_CStreamWorkspaceBound() - memory needed to initialize a ZSTD_CStream
+ * @cParams: The compression parameters to be used for compression.
+ *
+ * Return: A lower bound on the size of the workspace that is passed to
+ * ZSTD_initCStream() and ZSTD_initCStream_usingCDict().
+ */
+size_t ZSTD_CStreamWorkspaceBound(ZSTD_compressionParameters cParams);
+
+/**
+ * struct ZSTD_CStream - the zstd streaming compression context
+ */
+typedef struct ZSTD_CStream_s ZSTD_CStream;
+
+/*===== ZSTD_CStream management functions =====*/
+/**
+ * ZSTD_initCStream() - initialize a zstd streaming compression context
+ * @params: The zstd compression parameters.
+ * @pledgedSrcSize: If params.fParams.contentSizeFlag == 1 then the caller must
+ * pass the source size (zero means empty source). Otherwise,
+ * the caller may optionally pass the source size, or zero if
+ * unknown.
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace.
+ * Use ZSTD_CStreamWorkspaceBound(params.cParams) to determine
+ * how large the workspace must be.
+ *
+ * Return: The zstd streaming compression context.
+ */
+ZSTD_CStream *ZSTD_initCStream(ZSTD_parameters params,
+ unsigned long long pledgedSrcSize, void *workspace,
+ size_t workspaceSize);
+
+/**
+ * ZSTD_initCStream_usingCDict() - initialize a streaming compression context
+ * @cdict: The digested dictionary to use for compression.
+ * @pledgedSrcSize: Optionally the source size, or zero if unknown.
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace. Call ZSTD_CStreamWorkspaceBound()
+ * with the cParams used to initialize the cdict to determine
+ * how large the workspace must be.
+ *
+ * Return: The zstd streaming compression context.
+ */
+ZSTD_CStream *ZSTD_initCStream_usingCDict(const ZSTD_CDict *cdict,
+ unsigned long long pledgedSrcSize, void *workspace,
+ size_t workspaceSize);
+
+/*===== Streaming compression functions =====*/
+/**
+ * ZSTD_resetCStream() - reset the context using parameters from creation
+ * @zcs: The zstd streaming compression context to reset.
+ * @pledgedSrcSize: Optionally the source size, or zero if unknown.
+ *
+ * Resets the context using the parameters from creation. Skips dictionary
+ * loading, since it can be reused. If `pledgedSrcSize` is non-zero the frame
+ * content size is always written into the frame header.
+ *
+ * Return: Zero or an error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_resetCStream(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize);
+/**
+ * ZSTD_compressStream() - streaming compress some of input into output
+ * @zcs: The zstd streaming compression context.
+ * @output: Destination buffer. `output->pos` is updated to indicate how much
+ * compressed data was written.
+ * @input: Source buffer. `input->pos` is updated to indicate how much data was
+ * read. Note that it may not consume the entire input, in which case
+ * `input->pos < input->size`, and it's up to the caller to present
+ * remaining data again.
+ *
+ * The `input` and `output` buffers may be any size. Guaranteed to make some
+ * forward progress if `input` and `output` are not empty.
+ *
+ * Return: A hint for the number of bytes to use as the input for the next
+ * function call or an error, which can be checked using
+ * ZSTD_isError().
+ */
+size_t ZSTD_compressStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output,
+ ZSTD_inBuffer *input);
+/**
+ * ZSTD_flushStream() - flush internal buffers into output
+ * @zcs: The zstd streaming compression context.
+ * @output: Destination buffer. `output->pos` is updated to indicate how much
+ * compressed data was written.
+ *
+ * ZSTD_flushStream() must be called until it returns 0, meaning all the data
+ * has been flushed. Since ZSTD_flushStream() causes a block to be ended,
+ * calling it too often will degrade the compression ratio.
+ *
+ * Return: The number of bytes still present within internal buffers or an
+ * error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_flushStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output);
+/**
+ * ZSTD_endStream() - flush internal buffers into output and end the frame
+ * @zcs: The zstd streaming compression context.
+ * @output: Destination buffer. `output->pos` is updated to indicate how much
+ * compressed data was written.
+ *
+ * ZSTD_endStream() must be called until it returns 0, meaning all the data has
+ * been flushed and the frame epilogue has been written.
+ *
+ * Return: The number of bytes still present within internal buffers or an
+ * error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_endStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output);
+
+/**
+ * ZSTD_CStreamInSize() - recommended size for the input buffer
+ *
+ * Return: The recommended size for the input buffer.
+ */
+size_t ZSTD_CStreamInSize(void);
+/**
+ * ZSTD_CStreamOutSize() - recommended size for the output buffer
+ *
+ * When the output buffer is at least this large, it is guaranteed to be large
+ * enough to flush at least one complete compressed block.
+ *
+ * Return: The recommended size for the output buffer.
+ */
+size_t ZSTD_CStreamOutSize(void);
+
+
+
+/*-*****************************************************************************
+ * Streaming decompression - HowTo
+ *
+ * A ZSTD_DStream object is required to track streaming operations.
+ * Use ZSTD_initDStream() to initialize a ZSTD_DStream object.
+ * ZSTD_DStream objects can be re-used multiple times.
+ *
+ * Use ZSTD_decompressStream() repetitively to consume your input.
+ * The function will update both `pos` fields.
+ * If `input->pos < input->size`, some input has not been consumed.
+ * It's up to the caller to present again remaining data.
+ * If `output->pos < output->size`, decoder has flushed everything it could.
+ * Returns 0 iff a frame is completely decoded and fully flushed.
+ * Otherwise it returns a suggested next input size that will never load more
+ * than the current frame.
+ ******************************************************************************/
+
+/**
+ * ZSTD_DStreamWorkspaceBound() - memory needed to initialize a ZSTD_DStream
+ * @maxWindowSize: The maximum window size allowed for compressed frames.
+ *
+ * Return: A lower bound on the size of the workspace that is passed to
+ * ZSTD_initDStream() and ZSTD_initDStream_usingDDict().
+ */
+size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize);
+
+/**
+ * struct ZSTD_DStream - the zstd streaming decompression context
+ */
+typedef struct ZSTD_DStream_s ZSTD_DStream;
+/*===== ZSTD_DStream management functions =====*/
+/**
+ * ZSTD_initDStream() - initialize a zstd streaming decompression context
+ * @maxWindowSize: The maximum window size allowed for compressed frames.
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace.
+ * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine
+ * how large the workspace must be.
+ *
+ * Return: The zstd streaming decompression context.
+ */
+ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace,
+ size_t workspaceSize);
+/**
+ * ZSTD_initDStream_usingDDict() - initialize streaming decompression context
+ * @maxWindowSize: The maximum window size allowed for compressed frames.
+ * @ddict: The digested dictionary to use for decompression.
+ * @workspace: The workspace to emplace the context into. It must outlive
+ * the returned context.
+ * @workspaceSize: The size of workspace.
+ * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine
+ * how large the workspace must be.
+ *
+ * Return: The zstd streaming decompression context.
+ */
+ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize,
+ const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize);
+
+/*===== Streaming decompression functions =====*/
+/**
+ * ZSTD_resetDStream() - reset the context using parameters from creation
+ * @zds: The zstd streaming decompression context to reset.
+ *
+ * Resets the context using the parameters from creation. Skips dictionary
+ * loading, since it can be reused.
+ *
+ * Return: Zero or an error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_resetDStream(ZSTD_DStream *zds);
+/**
+ * ZSTD_decompressStream() - streaming decompress some of input into output
+ * @zds: The zstd streaming decompression context.
+ * @output: Destination buffer. `output.pos` is updated to indicate how much
+ * decompressed data was written.
+ * @input: Source buffer. `input.pos` is updated to indicate how much data was
+ * read. Note that it may not consume the entire input, in which case
+ * `input.pos < input.size`, and it's up to the caller to present
+ * remaining data again.
+ *
+ * The `input` and `output` buffers may be any size. Guaranteed to make some
+ * forward progress if `input` and `output` are not empty.
+ * ZSTD_decompressStream() will not consume the last byte of the frame until
+ * the entire frame is flushed.
+ *
+ * Return: Returns 0 iff a frame is completely decoded and fully flushed.
+ * Otherwise returns a hint for the number of bytes to use as the input
+ * for the next function call or an error, which can be checked using
+ * ZSTD_isError(). The size hint will never load more than the frame.
+ */
+size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output,
+ ZSTD_inBuffer *input);
+
+/**
+ * ZSTD_DStreamInSize() - recommended size for the input buffer
+ *
+ * Return: The recommended size for the input buffer.
+ */
+size_t ZSTD_DStreamInSize(void);
+/**
+ * ZSTD_DStreamOutSize() - recommended size for the output buffer
+ *
+ * When the output buffer is at least this large, it is guaranteed to be large
+ * enough to flush at least one complete decompressed block.
+ *
+ * Return: The recommended size for the output buffer.
+ */
+size_t ZSTD_DStreamOutSize(void);
+
+
+/* --- Constants ---*/
+#define ZSTD_MAGICNUMBER 0xFD2FB528 /* >= v0.8.0 */
+#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50U
+
+#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
+#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2)
+
+#define ZSTD_WINDOWLOG_MAX_32 27
+#define ZSTD_WINDOWLOG_MAX_64 27
+#define ZSTD_WINDOWLOG_MAX \
+ ((unsigned int)(sizeof(size_t) == 4 \
+ ? ZSTD_WINDOWLOG_MAX_32 \
+ : ZSTD_WINDOWLOG_MAX_64))
+#define ZSTD_WINDOWLOG_MIN 10
+#define ZSTD_HASHLOG_MAX ZSTD_WINDOWLOG_MAX
+#define ZSTD_HASHLOG_MIN 6
+#define ZSTD_CHAINLOG_MAX (ZSTD_WINDOWLOG_MAX+1)
+#define ZSTD_CHAINLOG_MIN ZSTD_HASHLOG_MIN
+#define ZSTD_HASHLOG3_MAX 17
+#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1)
+#define ZSTD_SEARCHLOG_MIN 1
+/* only for ZSTD_fast, other strategies are limited to 6 */
+#define ZSTD_SEARCHLENGTH_MAX 7
+/* only for ZSTD_btopt, other strategies are limited to 4 */
+#define ZSTD_SEARCHLENGTH_MIN 3
+#define ZSTD_TARGETLENGTH_MIN 4
+#define ZSTD_TARGETLENGTH_MAX 999
+
+/* for static allocation */
+#define ZSTD_FRAMEHEADERSIZE_MAX 18
+#define ZSTD_FRAMEHEADERSIZE_MIN 6
+static const size_t ZSTD_frameHeaderSize_prefix = 5;
+static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
+static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
+/* magic number + skippable frame length */
+static const size_t ZSTD_skippableHeaderSize = 8;
+
+
+/*-*************************************
+ * Compressed size functions
+ **************************************/
+
+/**
+ * ZSTD_findFrameCompressedSize() - returns the size of a compressed frame
+ * @src: Source buffer. It should point to the start of a zstd encoded frame
+ * or a skippable frame.
+ * @srcSize: The size of the source buffer. It must be at least as large as the
+ * size of the frame.
+ *
+ * Return: The compressed size of the frame pointed to by `src` or an error,
+ * which can be check with ZSTD_isError().
+ * Suitable to pass to ZSTD_decompress() or similar functions.
+ */
+size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize);
+
+/*-*************************************
+ * Decompressed size functions
+ **************************************/
+/**
+ * ZSTD_getFrameContentSize() - returns the content size in a zstd frame header
+ * @src: It should point to the start of a zstd encoded frame.
+ * @srcSize: The size of the source buffer. It must be at least as large as the
+ * frame header. `ZSTD_frameHeaderSize_max` is always large enough.
+ *
+ * Return: The frame content size stored in the frame header if known.
+ * `ZSTD_CONTENTSIZE_UNKNOWN` if the content size isn't stored in the
+ * frame header. `ZSTD_CONTENTSIZE_ERROR` on invalid input.
+ */
+unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
+
+/**
+ * ZSTD_findDecompressedSize() - returns decompressed size of a series of frames
+ * @src: It should point to the start of a series of zstd encoded and/or
+ * skippable frames.
+ * @srcSize: The exact size of the series of frames.
+ *
+ * If any zstd encoded frame in the series doesn't have the frame content size
+ * set, `ZSTD_CONTENTSIZE_UNKNOWN` is returned. But frame content size is always
+ * set when using ZSTD_compress(). The decompressed size can be very large.
+ * If the source is untrusted, the decompressed size could be wrong or
+ * intentionally modified. Always ensure the result fits within the
+ * application's authorized limits. ZSTD_findDecompressedSize() handles multiple
+ * frames, and so it must traverse the input to read each frame header. This is
+ * efficient as most of the data is skipped, however it does mean that all frame
+ * data must be present and valid.
+ *
+ * Return: Decompressed size of all the data contained in the frames if known.
+ * `ZSTD_CONTENTSIZE_UNKNOWN` if the decompressed size is unknown.
+ * `ZSTD_CONTENTSIZE_ERROR` if an error occurred.
+ */
+unsigned long long ZSTD_findDecompressedSize(const void *src, size_t srcSize);
+
+/*-*************************************
+ * Advanced compression functions
+ **************************************/
+/**
+ * ZSTD_checkCParams() - ensure parameter values remain within authorized range
+ * @cParams: The zstd compression parameters.
+ *
+ * Return: Zero or an error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams);
+
+/**
+ * ZSTD_adjustCParams() - optimize parameters for a given srcSize and dictSize
+ * @srcSize: Optionally the estimated source size, or zero if unknown.
+ * @dictSize: Optionally the estimated dictionary size, or zero if unknown.
+ *
+ * Return: The optimized parameters.
+ */
+ZSTD_compressionParameters ZSTD_adjustCParams(
+ ZSTD_compressionParameters cParams, unsigned long long srcSize,
+ size_t dictSize);
+
+/*--- Advanced decompression functions ---*/
+
+/**
+ * ZSTD_isFrame() - returns true iff the buffer starts with a valid frame
+ * @buffer: The source buffer to check.
+ * @size: The size of the source buffer, must be at least 4 bytes.
+ *
+ * Return: True iff the buffer starts with a zstd or skippable frame identifier.
+ */
+unsigned int ZSTD_isFrame(const void *buffer, size_t size);
+
+/**
+ * ZSTD_getDictID_fromDict() - returns the dictionary id stored in a dictionary
+ * @dict: The dictionary buffer.
+ * @dictSize: The size of the dictionary buffer.
+ *
+ * Return: The dictionary id stored within the dictionary or 0 if the
+ * dictionary is not a zstd dictionary. If it returns 0 the
+ * dictionary can still be loaded as a content-only dictionary.
+ */
+unsigned int ZSTD_getDictID_fromDict(const void *dict, size_t dictSize);
+
+/**
+ * ZSTD_getDictID_fromDDict() - returns the dictionary id stored in a ZSTD_DDict
+ * @ddict: The ddict to find the id of.
+ *
+ * Return: The dictionary id stored within `ddict` or 0 if the dictionary is not
+ * a zstd dictionary. If it returns 0 `ddict` will be loaded as a
+ * content-only dictionary.
+ */
+unsigned int ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict);
+
+/**
+ * ZSTD_getDictID_fromFrame() - returns the dictionary id stored in a zstd frame
+ * @src: Source buffer. It must be a zstd encoded frame.
+ * @srcSize: The size of the source buffer. It must be at least as large as the
+ * frame header. `ZSTD_frameHeaderSize_max` is always large enough.
+ *
+ * Return: The dictionary id required to decompress the frame stored within
+ * `src` or 0 if the dictionary id could not be decoded. It can return
+ * 0 if the frame does not require a dictionary, the dictionary id
+ * wasn't stored in the frame, `src` is not a zstd frame, or `srcSize`
+ * is too small.
+ */
+unsigned int ZSTD_getDictID_fromFrame(const void *src, size_t srcSize);
+
+/**
+ * struct ZSTD_frameParams - zstd frame parameters stored in the frame header
+ * @frameContentSize: The frame content size, or 0 if not present.
+ * @windowSize: The window size, or 0 if the frame is a skippable frame.
+ * @dictID: The dictionary id, or 0 if not present.
+ * @checksumFlag: Whether a checksum was used.
+ */
+typedef struct {
+ unsigned long long frameContentSize;
+ unsigned int windowSize;
+ unsigned int dictID;
+ unsigned int checksumFlag;
+} ZSTD_frameParams;
+
+/**
+ * ZSTD_getFrameParams() - extracts parameters from a zstd or skippable frame
+ * @fparamsPtr: On success the frame parameters are written here.
+ * @src: The source buffer. It must point to a zstd or skippable frame.
+ * @srcSize: The size of the source buffer. `ZSTD_frameHeaderSize_max` is
+ * always large enough to succeed.
+ *
+ * Return: 0 on success. If more data is required it returns how many bytes
+ * must be provided to make forward progress. Otherwise it returns
+ * an error, which can be checked using ZSTD_isError().
+ */
+size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src,
+ size_t srcSize);
+
+/*-*****************************************************************************
+ * Buffer-less and synchronous inner streaming functions
+ *
+ * This is an advanced API, giving full control over buffer management, for
+ * users which need direct control over memory.
+ * But it's also a complex one, with many restrictions (documented below).
+ * Prefer using normal streaming API for an easier experience
+ ******************************************************************************/
+
+/*-*****************************************************************************
+ * Buffer-less streaming compression (synchronous mode)
+ *
+ * A ZSTD_CCtx object is required to track streaming operations.
+ * Use ZSTD_initCCtx() to initialize a context.
+ * ZSTD_CCtx object can be re-used multiple times within successive compression
+ * operations.
+ *
+ * Start by initializing a context.
+ * Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary
+ * compression,
+ * or ZSTD_compressBegin_advanced(), for finer parameter control.
+ * It's also possible to duplicate a reference context which has already been
+ * initialized, using ZSTD_copyCCtx()
+ *
+ * Then, consume your input using ZSTD_compressContinue().
+ * There are some important considerations to keep in mind when using this
+ * advanced function :
+ * - ZSTD_compressContinue() has no internal buffer. It uses externally provided
+ * buffer only.
+ * - Interface is synchronous : input is consumed entirely and produce 1+
+ * (or more) compressed blocks.
+ * - Caller must ensure there is enough space in `dst` to store compressed data
+ * under worst case scenario. Worst case evaluation is provided by
+ * ZSTD_compressBound().
+ * ZSTD_compressContinue() doesn't guarantee recover after a failed
+ * compression.
+ * - ZSTD_compressContinue() presumes prior input ***is still accessible and
+ * unmodified*** (up to maximum distance size, see WindowLog).
+ * It remembers all previous contiguous blocks, plus one separated memory
+ * segment (which can itself consists of multiple contiguous blocks)
+ * - ZSTD_compressContinue() detects that prior input has been overwritten when
+ * `src` buffer overlaps. In which case, it will "discard" the relevant memory
+ * section from its history.
+ *
+ * Finish a frame with ZSTD_compressEnd(), which will write the last block(s)
+ * and optional checksum. It's possible to use srcSize==0, in which case, it
+ * will write a final empty block to end the frame. Without last block mark,
+ * frames will be considered unfinished (corrupted) by decoders.
+ *
+ * `ZSTD_CCtx` object can be re-used (ZSTD_compressBegin()) to compress some new
+ * frame.
+ ******************************************************************************/
+
+/*===== Buffer-less streaming compression functions =====*/
+size_t ZSTD_compressBegin(ZSTD_CCtx *cctx, int compressionLevel);
+size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx *cctx, const void *dict,
+ size_t dictSize, int compressionLevel);
+size_t ZSTD_compressBegin_advanced(ZSTD_CCtx *cctx, const void *dict,
+ size_t dictSize, ZSTD_parameters params,
+ unsigned long long pledgedSrcSize);
+size_t ZSTD_copyCCtx(ZSTD_CCtx *cctx, const ZSTD_CCtx *preparedCCtx,
+ unsigned long long pledgedSrcSize);
+size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx *cctx, const ZSTD_CDict *cdict,
+ unsigned long long pledgedSrcSize);
+size_t ZSTD_compressContinue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+size_t ZSTD_compressEnd(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+
+
+
+/*-*****************************************************************************
+ * Buffer-less streaming decompression (synchronous mode)
+ *
+ * A ZSTD_DCtx object is required to track streaming operations.
+ * Use ZSTD_initDCtx() to initialize a context.
+ * A ZSTD_DCtx object can be re-used multiple times.
+ *
+ * First typical operation is to retrieve frame parameters, using
+ * ZSTD_getFrameParams(). It fills a ZSTD_frameParams structure which provide
+ * important information to correctly decode the frame, such as the minimum
+ * rolling buffer size to allocate to decompress data (`windowSize`), and the
+ * dictionary ID used.
+ * Note: content size is optional, it may not be present. 0 means unknown.
+ * Note that these values could be wrong, either because of data malformation,
+ * or because an attacker is spoofing deliberate false information. As a
+ * consequence, check that values remain within valid application range,
+ * especially `windowSize`, before allocation. Each application can set its own
+ * limit, depending on local restrictions. For extended interoperability, it is
+ * recommended to support at least 8 MB.
+ * Frame parameters are extracted from the beginning of the compressed frame.
+ * Data fragment must be large enough to ensure successful decoding, typically
+ * `ZSTD_frameHeaderSize_max` bytes.
+ * Result: 0: successful decoding, the `ZSTD_frameParams` structure is filled.
+ * >0: `srcSize` is too small, provide at least this many bytes.
+ * errorCode, which can be tested using ZSTD_isError().
+ *
+ * Start decompression, with ZSTD_decompressBegin() or
+ * ZSTD_decompressBegin_usingDict(). Alternatively, you can copy a prepared
+ * context, using ZSTD_copyDCtx().
+ *
+ * Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue()
+ * alternatively.
+ * ZSTD_nextSrcSizeToDecompress() tells how many bytes to provide as 'srcSize'
+ * to ZSTD_decompressContinue().
+ * ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will
+ * fail.
+ *
+ * The result of ZSTD_decompressContinue() is the number of bytes regenerated
+ * within 'dst' (necessarily <= dstCapacity). It can be zero, which is not an
+ * error; it just means ZSTD_decompressContinue() has decoded some metadata
+ * item. It can also be an error code, which can be tested with ZSTD_isError().
+ *
+ * ZSTD_decompressContinue() needs previous data blocks during decompression, up
+ * to `windowSize`. They should preferably be located contiguously, prior to
+ * current block. Alternatively, a round buffer of sufficient size is also
+ * possible. Sufficient size is determined by frame parameters.
+ * ZSTD_decompressContinue() is very sensitive to contiguity, if 2 blocks don't
+ * follow each other, make sure that either the compressor breaks contiguity at
+ * the same place, or that previous contiguous segment is large enough to
+ * properly handle maximum back-reference.
+ *
+ * A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero.
+ * Context can then be reset to start a new decompression.
+ *
+ * Note: it's possible to know if next input to present is a header or a block,
+ * using ZSTD_nextInputType(). This information is not required to properly
+ * decode a frame.
+ *
+ * == Special case: skippable frames ==
+ *
+ * Skippable frames allow integration of user-defined data into a flow of
+ * concatenated frames. Skippable frames will be ignored (skipped) by a
+ * decompressor. The format of skippable frames is as follows:
+ * a) Skippable frame ID - 4 Bytes, Little endian format, any value from
+ * 0x184D2A50 to 0x184D2A5F
+ * b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
+ * c) Frame Content - any content (User Data) of length equal to Frame Size
+ * For skippable frames ZSTD_decompressContinue() always returns 0.
+ * For skippable frames ZSTD_getFrameParams() returns fparamsPtr->windowLog==0
+ * what means that a frame is skippable.
+ * Note: If fparamsPtr->frameContentSize==0, it is ambiguous: the frame might
+ * actually be a zstd encoded frame with no content. For purposes of
+ * decompression, it is valid in both cases to skip the frame using
+ * ZSTD_findFrameCompressedSize() to find its size in bytes.
+ * It also returns frame size as fparamsPtr->frameContentSize.
+ ******************************************************************************/
+
+/*===== Buffer-less streaming decompression functions =====*/
+size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx);
+size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict,
+ size_t dictSize);
+void ZSTD_copyDCtx(ZSTD_DCtx *dctx, const ZSTD_DCtx *preparedDCtx);
+size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx);
+size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+typedef enum {
+ ZSTDnit_frameHeader,
+ ZSTDnit_blockHeader,
+ ZSTDnit_block,
+ ZSTDnit_lastBlock,
+ ZSTDnit_checksum,
+ ZSTDnit_skippableFrame
+} ZSTD_nextInputType_e;
+ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx);
+
+/*-*****************************************************************************
+ * Block functions
+ *
+ * Block functions produce and decode raw zstd blocks, without frame metadata.
+ * Frame metadata cost is typically ~18 bytes, which can be non-negligible for
+ * very small blocks (< 100 bytes). User will have to take in charge required
+ * information to regenerate data, such as compressed and content sizes.
+ *
+ * A few rules to respect:
+ * - Compressing and decompressing require a context structure
+ * + Use ZSTD_initCCtx() and ZSTD_initDCtx()
+ * - It is necessary to init context before starting
+ * + compression : ZSTD_compressBegin()
+ * + decompression : ZSTD_decompressBegin()
+ * + variants _usingDict() are also allowed
+ * + copyCCtx() and copyDCtx() work too
+ * - Block size is limited, it must be <= ZSTD_getBlockSizeMax()
+ * + If you need to compress more, cut data into multiple blocks
+ * + Consider using the regular ZSTD_compress() instead, as frame metadata
+ * costs become negligible when source size is large.
+ * - When a block is considered not compressible enough, ZSTD_compressBlock()
+ * result will be zero. In which case, nothing is produced into `dst`.
+ * + User must test for such outcome and deal directly with uncompressed data
+ * + ZSTD_decompressBlock() doesn't accept uncompressed data as input!!!
+ * + In case of multiple successive blocks, decoder must be informed of
+ * uncompressed block existence to follow proper history. Use
+ * ZSTD_insertBlock() in such a case.
+ ******************************************************************************/
+
+/* Define for static allocation */
+#define ZSTD_BLOCKSIZE_ABSOLUTEMAX (128 * 1024)
+/*===== Raw zstd block functions =====*/
+size_t ZSTD_getBlockSizeMax(ZSTD_CCtx *cctx);
+size_t ZSTD_compressBlock(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity,
+ const void *src, size_t srcSize);
+size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart,
+ size_t blockSize);
+
+#endif /* ZSTD_H */
diff --git a/lib/Kconfig b/lib/Kconfig
index cb6ce940a8..dca93b80d0 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -21,6 +21,11 @@ config LZ4_DECOMPRESS
bool "include lz4 uncompression support"
select UNCOMPRESS
+config ZSTD_DECOMPRESS
+ bool "include zstd uncompression support"
+ select UNCOMPRESS
+ select XXHASH
+
config XZ_DECOMPRESS
bool "include xz uncompression support"
select UNCOMPRESS
diff --git a/lib/Makefile b/lib/Makefile
index db9c895e46..e5cf32c162 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -36,6 +36,7 @@ obj-y += random.o
obj-$(CONFIG_IMAGE_SPARSE) += image-sparse.o
obj-y += lzo/
obj-$(CONFIG_LZ4_DECOMPRESS) += lz4/
+obj-$(CONFIG_ZSTD_DECOMPRESS) += zstd/
obj-y += show_progress.o
obj-$(CONFIG_LZO_DECOMPRESS) += decompress_unlzo.o
obj-$(CONFIG_LZ4_DECOMPRESS) += decompress_unlz4.o
diff --git a/lib/zstd/Makefile b/lib/zstd/Makefile
new file mode 100644
index 0000000000..0c4f56c50c
--- /dev/null
+++ b/lib/zstd/Makefile
@@ -0,0 +1,6 @@
+obj-$(CONFIG_ZSTD_DECOMPRESS) += zstd_decompress.o
+
+ccflags-y += -O3
+
+zstd_decompress-y := huf_decompress.o decompress.o
+zstd_decompress-y += entropy_common.o fse_decompress.o zstd_common.o
diff --git a/lib/zstd/bitstream.h b/lib/zstd/bitstream.h
new file mode 100644
index 0000000000..a826b99e1d
--- /dev/null
+++ b/lib/zstd/bitstream.h
@@ -0,0 +1,374 @@
+/*
+ * bitstream
+ * Part of FSE library
+ * header file (to include)
+ * Copyright (C) 2013-2016, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * 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").
+ *
+ * You can contact the author at :
+ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ */
+#ifndef BITSTREAM_H_MODULE
+#define BITSTREAM_H_MODULE
+
+/*
+* This API consists of small unitary functions, which must be inlined for best performance.
+* Since link-time-optimization is not available for all compilers,
+* these functions are defined into a .h to be included.
+*/
+
+/*-****************************************
+* Dependencies
+******************************************/
+#include "error_private.h" /* error codes and messages */
+#include "mem.h" /* unaligned access routines */
+
+/*=========================================
+* Target specific
+=========================================*/
+#define STREAM_ACCUMULATOR_MIN_32 25
+#define STREAM_ACCUMULATOR_MIN_64 57
+#define STREAM_ACCUMULATOR_MIN ((U32)(ZSTD_32bits() ? STREAM_ACCUMULATOR_MIN_32 : STREAM_ACCUMULATOR_MIN_64))
+
+/*-******************************************
+* bitStream encoding API (write forward)
+********************************************/
+/* bitStream can mix input from multiple sources.
+* A critical property of these streams is that they encode and decode in **reverse** direction.
+* So the first bit sequence you add will be the last to be read, like a LIFO stack.
+*/
+typedef struct {
+ size_t bitContainer;
+ int bitPos;
+ char *startPtr;
+ char *ptr;
+ char *endPtr;
+} BIT_CStream_t;
+
+ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *dstBuffer, size_t dstCapacity);
+ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits);
+ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC);
+ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC);
+
+/* Start with initCStream, providing the size of buffer to write into.
+* bitStream will never write outside of this buffer.
+* `dstCapacity` must be >= sizeof(bitD->bitContainer), otherwise @return will be an error code.
+*
+* bits are first added to a local register.
+* Local register is size_t, hence 64-bits on 64-bits systems, or 32-bits on 32-bits systems.
+* Writing data into memory is an explicit operation, performed by the flushBits function.
+* Hence keep track how many bits are potentially stored into local register to avoid register overflow.
+* After a flushBits, a maximum of 7 bits might still be stored into local register.
+*
+* Avoid storing elements of more than 24 bits if you want compatibility with 32-bits bitstream readers.
+*
+* Last operation is to close the bitStream.
+* The function returns the final size of CStream in bytes.
+* If data couldn't fit into `dstBuffer`, it will return a 0 ( == not storable)
+*/
+
+/*-********************************************
+* bitStream decoding API (read backward)
+**********************************************/
+typedef struct {
+ size_t bitContainer;
+ unsigned bitsConsumed;
+ const char *ptr;
+ const char *start;
+} BIT_DStream_t;
+
+typedef enum {
+ BIT_DStream_unfinished = 0,
+ BIT_DStream_endOfBuffer = 1,
+ BIT_DStream_completed = 2,
+ BIT_DStream_overflow = 3
+} BIT_DStream_status; /* result of BIT_reloadDStream() */
+/* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... :( */
+
+ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize);
+ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, unsigned nbBits);
+ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD);
+ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *bitD);
+
+/* Start by invoking BIT_initDStream().
+* A chunk of the bitStream is then stored into a local register.
+* Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t).
+* You can then retrieve bitFields stored into the local register, **in reverse order**.
+* Local register is explicitly reloaded from memory by the BIT_reloadDStream() method.
+* A reload guarantee a minimum of ((8*sizeof(bitD->bitContainer))-7) bits when its result is BIT_DStream_unfinished.
+* Otherwise, it can be less than that, so proceed accordingly.
+* Checking if DStream has reached its end can be performed with BIT_endOfDStream().
+*/
+
+/*-****************************************
+* unsafe API
+******************************************/
+ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits);
+/* faster, but works only if value is "clean", meaning all high bits above nbBits are 0 */
+
+ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC);
+/* unsafe version; does not check buffer overflow */
+
+ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, unsigned nbBits);
+/* faster, but works only if nbBits >= 1 */
+
+/*-**************************************************************
+* Internal functions
+****************************************************************/
+ZSTD_STATIC unsigned BIT_highbit32(register U32 val) { return 31 - __builtin_clz(val); }
+
+/*===== Local Constants =====*/
+static const unsigned BIT_mask[] = {0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF,
+ 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF,
+ 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF, 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF}; /* up to 26 bits */
+
+/*-**************************************************************
+* bitStream encoding
+****************************************************************/
+/*! BIT_initCStream() :
+ * `dstCapacity` must be > sizeof(void*)
+ * @return : 0 if success,
+ otherwise an error code (can be tested using ERR_isError() ) */
+ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *startPtr, size_t dstCapacity)
+{
+ bitC->bitContainer = 0;
+ bitC->bitPos = 0;
+ bitC->startPtr = (char *)startPtr;
+ bitC->ptr = bitC->startPtr;
+ bitC->endPtr = bitC->startPtr + dstCapacity - sizeof(bitC->ptr);
+ if (dstCapacity <= sizeof(bitC->ptr))
+ return ERROR(dstSize_tooSmall);
+ return 0;
+}
+
+/*! BIT_addBits() :
+ can add up to 26 bits into `bitC`.
+ Does not check for register overflow ! */
+ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits)
+{
+ bitC->bitContainer |= (value & BIT_mask[nbBits]) << bitC->bitPos;
+ bitC->bitPos += nbBits;
+}
+
+/*! BIT_addBitsFast() :
+ * works only if `value` is _clean_, meaning all high bits above nbBits are 0 */
+ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits)
+{
+ bitC->bitContainer |= value << bitC->bitPos;
+ bitC->bitPos += nbBits;
+}
+
+/*! BIT_flushBitsFast() :
+ * unsafe version; does not check buffer overflow */
+ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC)
+{
+ size_t const nbBytes = bitC->bitPos >> 3;
+ ZSTD_writeLEST(bitC->ptr, bitC->bitContainer);
+ bitC->ptr += nbBytes;
+ bitC->bitPos &= 7;
+ bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */
+}
+
+/*! BIT_flushBits() :
+ * safe version; check for buffer overflow, and prevents it.
+ * note : does not signal buffer overflow. This will be revealed later on using BIT_closeCStream() */
+ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC)
+{
+ size_t const nbBytes = bitC->bitPos >> 3;
+ ZSTD_writeLEST(bitC->ptr, bitC->bitContainer);
+ bitC->ptr += nbBytes;
+ if (bitC->ptr > bitC->endPtr)
+ bitC->ptr = bitC->endPtr;
+ bitC->bitPos &= 7;
+ bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */
+}
+
+/*! BIT_closeCStream() :
+ * @return : size of CStream, in bytes,
+ or 0 if it could not fit into dstBuffer */
+ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC)
+{
+ BIT_addBitsFast(bitC, 1, 1); /* endMark */
+ BIT_flushBits(bitC);
+
+ if (bitC->ptr >= bitC->endPtr)
+ return 0; /* doesn't fit within authorized budget : cancel */
+
+ return (bitC->ptr - bitC->startPtr) + (bitC->bitPos > 0);
+}
+
+/*-********************************************************
+* bitStream decoding
+**********************************************************/
+/*! BIT_initDStream() :
+* Initialize a BIT_DStream_t.
+* `bitD` : a pointer to an already allocated BIT_DStream_t structure.
+* `srcSize` must be the *exact* size of the bitStream, in bytes.
+* @return : size of stream (== srcSize) or an errorCode if a problem is detected
+*/
+ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize)
+{
+ if (srcSize < 1) {
+ memset(bitD, 0, sizeof(*bitD));
+ return ERROR(srcSize_wrong);
+ }
+
+ if (srcSize >= sizeof(bitD->bitContainer)) { /* normal case */
+ bitD->start = (const char *)srcBuffer;
+ bitD->ptr = (const char *)srcBuffer + srcSize - sizeof(bitD->bitContainer);
+ bitD->bitContainer = ZSTD_readLEST(bitD->ptr);
+ {
+ BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1];
+ bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0; /* ensures bitsConsumed is always set */
+ if (lastByte == 0)
+ return ERROR(GENERIC); /* endMark not present */
+ }
+ } else {
+ bitD->start = (const char *)srcBuffer;
+ bitD->ptr = bitD->start;
+ bitD->bitContainer = *(const BYTE *)(bitD->start);
+ switch (srcSize) {
+ case 7: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[6]) << (sizeof(bitD->bitContainer) * 8 - 16);
+ case 6: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[5]) << (sizeof(bitD->bitContainer) * 8 - 24);
+ case 5: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[4]) << (sizeof(bitD->bitContainer) * 8 - 32);
+ case 4: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[3]) << 24;
+ case 3: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[2]) << 16;
+ case 2: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[1]) << 8;
+ default:;
+ }
+ {
+ BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1];
+ bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0;
+ if (lastByte == 0)
+ return ERROR(GENERIC); /* endMark not present */
+ }
+ bitD->bitsConsumed += (U32)(sizeof(bitD->bitContainer) - srcSize) * 8;
+ }
+
+ return srcSize;
+}
+
+ZSTD_STATIC size_t BIT_getUpperBits(size_t bitContainer, U32 const start) { return bitContainer >> start; }
+
+ZSTD_STATIC size_t BIT_getMiddleBits(size_t bitContainer, U32 const start, U32 const nbBits) { return (bitContainer >> start) & BIT_mask[nbBits]; }
+
+ZSTD_STATIC size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits) { return bitContainer & BIT_mask[nbBits]; }
+
+/*! BIT_lookBits() :
+ * Provides next n bits from local register.
+ * local register is not modified.
+ * On 32-bits, maxNbBits==24.
+ * On 64-bits, maxNbBits==56.
+ * @return : value extracted
+ */
+ZSTD_STATIC size_t BIT_lookBits(const BIT_DStream_t *bitD, U32 nbBits)
+{
+ U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1;
+ return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask - nbBits) & bitMask);
+}
+
+/*! BIT_lookBitsFast() :
+* unsafe version; only works only if nbBits >= 1 */
+ZSTD_STATIC size_t BIT_lookBitsFast(const BIT_DStream_t *bitD, U32 nbBits)
+{
+ U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1;
+ return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask + 1) - nbBits) & bitMask);
+}
+
+ZSTD_STATIC void BIT_skipBits(BIT_DStream_t *bitD, U32 nbBits) { bitD->bitsConsumed += nbBits; }
+
+/*! BIT_readBits() :
+ * Read (consume) next n bits from local register and update.
+ * Pay attention to not read more than nbBits contained into local register.
+ * @return : extracted value.
+ */
+ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, U32 nbBits)
+{
+ size_t const value = BIT_lookBits(bitD, nbBits);
+ BIT_skipBits(bitD, nbBits);
+ return value;
+}
+
+/*! BIT_readBitsFast() :
+* unsafe version; only works only if nbBits >= 1 */
+ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, U32 nbBits)
+{
+ size_t const value = BIT_lookBitsFast(bitD, nbBits);
+ BIT_skipBits(bitD, nbBits);
+ return value;
+}
+
+/*! BIT_reloadDStream() :
+* Refill `bitD` from buffer previously set in BIT_initDStream() .
+* This function is safe, it guarantees it will not read beyond src buffer.
+* @return : status of `BIT_DStream_t` internal register.
+ if status == BIT_DStream_unfinished, internal register is filled with >= (sizeof(bitD->bitContainer)*8 - 7) bits */
+ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD)
+{
+ if (bitD->bitsConsumed > (sizeof(bitD->bitContainer) * 8)) /* should not happen => corruption detected */
+ return BIT_DStream_overflow;
+
+ if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) {
+ bitD->ptr -= bitD->bitsConsumed >> 3;
+ bitD->bitsConsumed &= 7;
+ bitD->bitContainer = ZSTD_readLEST(bitD->ptr);
+ return BIT_DStream_unfinished;
+ }
+ if (bitD->ptr == bitD->start) {
+ if (bitD->bitsConsumed < sizeof(bitD->bitContainer) * 8)
+ return BIT_DStream_endOfBuffer;
+ return BIT_DStream_completed;
+ }
+ {
+ U32 nbBytes = bitD->bitsConsumed >> 3;
+ BIT_DStream_status result = BIT_DStream_unfinished;
+ if (bitD->ptr - nbBytes < bitD->start) {
+ nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */
+ result = BIT_DStream_endOfBuffer;
+ }
+ bitD->ptr -= nbBytes;
+ bitD->bitsConsumed -= nbBytes * 8;
+ bitD->bitContainer = ZSTD_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */
+ return result;
+ }
+}
+
+/*! BIT_endOfDStream() :
+* @return Tells if DStream has exactly reached its end (all bits consumed).
+*/
+ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *DStream)
+{
+ return ((DStream->ptr == DStream->start) && (DStream->bitsConsumed == sizeof(DStream->bitContainer) * 8));
+}
+
+#endif /* BITSTREAM_H_MODULE */
diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
new file mode 100644
index 0000000000..8203b815ca
--- /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 <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");
diff --git a/lib/zstd/entropy_common.c b/lib/zstd/entropy_common.c
new file mode 100644
index 0000000000..2b0a643c32
--- /dev/null
+++ b/lib/zstd/entropy_common.c
@@ -0,0 +1,243 @@
+/*
+ * Common functions of New Generation Entropy library
+ * Copyright (C) 2016, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * 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").
+ *
+ * You can contact the author at :
+ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ */
+
+/* *************************************
+* Dependencies
+***************************************/
+#include "error_private.h" /* ERR_*, ERROR */
+#include "fse.h"
+#include "huf.h"
+#include "mem.h"
+
+/*=== Version ===*/
+unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; }
+
+/*=== Error Management ===*/
+unsigned FSE_isError(size_t code) { return ERR_isError(code); }
+
+unsigned HUF_isError(size_t code) { return ERR_isError(code); }
+
+/*-**************************************************************
+* FSE NCount encoding-decoding
+****************************************************************/
+size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSVPtr, unsigned *tableLogPtr, const void *headerBuffer, size_t hbSize)
+{
+ const BYTE *const istart = (const BYTE *)headerBuffer;
+ const BYTE *const iend = istart + hbSize;
+ const BYTE *ip = istart;
+ int nbBits;
+ int remaining;
+ int threshold;
+ U32 bitStream;
+ int bitCount;
+ unsigned charnum = 0;
+ int previous0 = 0;
+
+ if (hbSize < 4)
+ return ERROR(srcSize_wrong);
+ bitStream = ZSTD_readLE32(ip);
+ nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */
+ if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX)
+ return ERROR(tableLog_tooLarge);
+ bitStream >>= 4;
+ bitCount = 4;
+ *tableLogPtr = nbBits;
+ remaining = (1 << nbBits) + 1;
+ threshold = 1 << nbBits;
+ nbBits++;
+
+ while ((remaining > 1) & (charnum <= *maxSVPtr)) {
+ if (previous0) {
+ unsigned n0 = charnum;
+ while ((bitStream & 0xFFFF) == 0xFFFF) {
+ n0 += 24;
+ if (ip < iend - 5) {
+ ip += 2;
+ bitStream = ZSTD_readLE32(ip) >> bitCount;
+ } else {
+ bitStream >>= 16;
+ bitCount += 16;
+ }
+ }
+ while ((bitStream & 3) == 3) {
+ n0 += 3;
+ bitStream >>= 2;
+ bitCount += 2;
+ }
+ n0 += bitStream & 3;
+ bitCount += 2;
+ if (n0 > *maxSVPtr)
+ return ERROR(maxSymbolValue_tooSmall);
+ while (charnum < n0)
+ normalizedCounter[charnum++] = 0;
+ if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) {
+ ip += bitCount >> 3;
+ bitCount &= 7;
+ bitStream = ZSTD_readLE32(ip) >> bitCount;
+ } else {
+ bitStream >>= 2;
+ }
+ }
+ {
+ int const max = (2 * threshold - 1) - remaining;
+ int count;
+
+ if ((bitStream & (threshold - 1)) < (U32)max) {
+ count = bitStream & (threshold - 1);
+ bitCount += nbBits - 1;
+ } else {
+ count = bitStream & (2 * threshold - 1);
+ if (count >= threshold)
+ count -= max;
+ bitCount += nbBits;
+ }
+
+ count--; /* extra accuracy */
+ remaining -= count < 0 ? -count : count; /* -1 means +1 */
+ normalizedCounter[charnum++] = (short)count;
+ previous0 = !count;
+ while (remaining < threshold) {
+ nbBits--;
+ threshold >>= 1;
+ }
+
+ if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) {
+ ip += bitCount >> 3;
+ bitCount &= 7;
+ } else {
+ bitCount -= (int)(8 * (iend - 4 - ip));
+ ip = iend - 4;
+ }
+ bitStream = ZSTD_readLE32(ip) >> (bitCount & 31);
+ }
+ } /* while ((remaining>1) & (charnum<=*maxSVPtr)) */
+ if (remaining != 1)
+ return ERROR(corruption_detected);
+ if (bitCount > 32)
+ return ERROR(corruption_detected);
+ *maxSVPtr = charnum - 1;
+
+ ip += (bitCount + 7) >> 3;
+ return ip - istart;
+}
+
+/*! HUF_readStats() :
+ Read compact Huffman tree, saved by HUF_writeCTable().
+ `huffWeight` is destination buffer.
+ `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32.
+ @return : size read from `src` , or an error Code .
+ Note : Needed by HUF_readCTable() and HUF_readDTableX?() .
+*/
+size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
+{
+ U32 weightTotal;
+ const BYTE *ip = (const BYTE *)src;
+ size_t iSize;
+ size_t oSize;
+
+ if (!srcSize)
+ return ERROR(srcSize_wrong);
+ iSize = ip[0];
+ /* memset(huffWeight, 0, hwSize); */ /* is not necessary, even though some analyzer complain ... */
+
+ if (iSize >= 128) { /* special header */
+ oSize = iSize - 127;
+ iSize = ((oSize + 1) / 2);
+ if (iSize + 1 > srcSize)
+ return ERROR(srcSize_wrong);
+ if (oSize >= hwSize)
+ return ERROR(corruption_detected);
+ ip += 1;
+ {
+ U32 n;
+ for (n = 0; n < oSize; n += 2) {
+ huffWeight[n] = ip[n / 2] >> 4;
+ huffWeight[n + 1] = ip[n / 2] & 15;
+ }
+ }
+ } else { /* header compressed with FSE (normal case) */
+ if (iSize + 1 > srcSize)
+ return ERROR(srcSize_wrong);
+ oSize = FSE_decompress_wksp(huffWeight, hwSize - 1, ip + 1, iSize, 6, workspace, workspaceSize); /* max (hwSize-1) values decoded, as last one is implied */
+ if (FSE_isError(oSize))
+ return oSize;
+ }
+
+ /* collect weight stats */
+ memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32));
+ weightTotal = 0;
+ {
+ U32 n;
+ for (n = 0; n < oSize; n++) {
+ if (huffWeight[n] >= HUF_TABLELOG_MAX)
+ return ERROR(corruption_detected);
+ rankStats[huffWeight[n]]++;
+ weightTotal += (1 << huffWeight[n]) >> 1;
+ }
+ }
+ if (weightTotal == 0)
+ return ERROR(corruption_detected);
+
+ /* get last non-null symbol weight (implied, total must be 2^n) */
+ {
+ U32 const tableLog = BIT_highbit32(weightTotal) + 1;
+ if (tableLog > HUF_TABLELOG_MAX)
+ return ERROR(corruption_detected);
+ *tableLogPtr = tableLog;
+ /* determine last weight */
+ {
+ U32 const total = 1 << tableLog;
+ U32 const rest = total - weightTotal;
+ U32 const verif = 1 << BIT_highbit32(rest);
+ U32 const lastWeight = BIT_highbit32(rest) + 1;
+ if (verif != rest)
+ return ERROR(corruption_detected); /* last value must be a clean power of 2 */
+ huffWeight[oSize] = (BYTE)lastWeight;
+ rankStats[lastWeight]++;
+ }
+ }
+
+ /* check tree construction validity */
+ if ((rankStats[1] < 2) || (rankStats[1] & 1))
+ return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */
+
+ /* results */
+ *nbSymbolsPtr = (U32)(oSize + 1);
+ return iSize + 1;
+}
diff --git a/lib/zstd/error_private.h b/lib/zstd/error_private.h
new file mode 100644
index 0000000000..1a60b31f70
--- /dev/null
+++ b/lib/zstd/error_private.h
@@ -0,0 +1,53 @@
+/**
+ * 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").
+ */
+
+/* Note : this module is expected to remain private, do not expose it */
+
+#ifndef ERROR_H_MODULE
+#define ERROR_H_MODULE
+
+/* ****************************************
+* Dependencies
+******************************************/
+#include <linux/types.h> /* size_t */
+#include <linux/zstd.h> /* enum list */
+
+/* ****************************************
+* Compiler-specific
+******************************************/
+#define ERR_STATIC static __attribute__((unused))
+
+/*-****************************************
+* Customization (error_public.h)
+******************************************/
+typedef ZSTD_ErrorCode ERR_enum;
+#define PREFIX(name) ZSTD_error_##name
+
+/*-****************************************
+* Error codes handling
+******************************************/
+#define ERROR(name) ((size_t)-PREFIX(name))
+
+ERR_STATIC unsigned ERR_isError(size_t code) { return (code > ERROR(maxCode)); }
+
+ERR_STATIC ERR_enum ERR_getErrorCode(size_t code)
+{
+ if (!ERR_isError(code))
+ return (ERR_enum)0;
+ return (ERR_enum)(0 - code);
+}
+
+#endif /* ERROR_H_MODULE */
diff --git a/lib/zstd/fse.h b/lib/zstd/fse.h
new file mode 100644
index 0000000000..7460ab04b1
--- /dev/null
+++ b/lib/zstd/fse.h
@@ -0,0 +1,575 @@
+/*
+ * FSE : Finite State Entropy codec
+ * Public Prototypes declaration
+ * Copyright (C) 2013-2016, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * 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").
+ *
+ * You can contact the author at :
+ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ */
+#ifndef FSE_H
+#define FSE_H
+
+/*-*****************************************
+* Dependencies
+******************************************/
+#include <linux/types.h> /* size_t, ptrdiff_t */
+
+/*-*****************************************
+* FSE_PUBLIC_API : control library symbols visibility
+******************************************/
+#define FSE_PUBLIC_API
+
+/*------ Version ------*/
+#define FSE_VERSION_MAJOR 0
+#define FSE_VERSION_MINOR 9
+#define FSE_VERSION_RELEASE 0
+
+#define FSE_LIB_VERSION FSE_VERSION_MAJOR.FSE_VERSION_MINOR.FSE_VERSION_RELEASE
+#define FSE_QUOTE(str) #str
+#define FSE_EXPAND_AND_QUOTE(str) FSE_QUOTE(str)
+#define FSE_VERSION_STRING FSE_EXPAND_AND_QUOTE(FSE_LIB_VERSION)
+
+#define FSE_VERSION_NUMBER (FSE_VERSION_MAJOR * 100 * 100 + FSE_VERSION_MINOR * 100 + FSE_VERSION_RELEASE)
+FSE_PUBLIC_API unsigned FSE_versionNumber(void); /**< library version number; to be used when checking dll version */
+
+/*-*****************************************
+* Tool functions
+******************************************/
+FSE_PUBLIC_API size_t FSE_compressBound(size_t size); /* maximum compressed size */
+
+/* Error Management */
+FSE_PUBLIC_API unsigned FSE_isError(size_t code); /* tells if a return value is an error code */
+
+/*-*****************************************
+* FSE detailed API
+******************************************/
+/*!
+FSE_compress() does the following:
+1. count symbol occurrence from source[] into table count[]
+2. normalize counters so that sum(count[]) == Power_of_2 (2^tableLog)
+3. save normalized counters to memory buffer using writeNCount()
+4. build encoding table 'CTable' from normalized counters
+5. encode the data stream using encoding table 'CTable'
+
+FSE_decompress() does the following:
+1. read normalized counters with readNCount()
+2. build decoding table 'DTable' from normalized counters
+3. decode the data stream using decoding table 'DTable'
+
+The following API allows targeting specific sub-functions for advanced tasks.
+For example, it's possible to compress several blocks using the same 'CTable',
+or to save and provide normalized distribution using external method.
+*/
+
+/* *** COMPRESSION *** */
+/*! FSE_optimalTableLog():
+ dynamically downsize 'tableLog' when conditions are met.
+ It saves CPU time, by using smaller tables, while preserving or even improving compression ratio.
+ @return : recommended tableLog (necessarily <= 'maxTableLog') */
+FSE_PUBLIC_API unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue);
+
+/*! FSE_normalizeCount():
+ normalize counts so that sum(count[]) == Power_of_2 (2^tableLog)
+ 'normalizedCounter' is a table of short, of minimum size (maxSymbolValue+1).
+ @return : tableLog,
+ or an errorCode, which can be tested using FSE_isError() */
+FSE_PUBLIC_API size_t FSE_normalizeCount(short *normalizedCounter, unsigned tableLog, const unsigned *count, size_t srcSize, unsigned maxSymbolValue);
+
+/*! FSE_NCountWriteBound():
+ Provides the maximum possible size of an FSE normalized table, given 'maxSymbolValue' and 'tableLog'.
+ Typically useful for allocation purpose. */
+FSE_PUBLIC_API size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog);
+
+/*! FSE_writeNCount():
+ Compactly save 'normalizedCounter' into 'buffer'.
+ @return : size of the compressed table,
+ or an errorCode, which can be tested using FSE_isError(). */
+FSE_PUBLIC_API size_t FSE_writeNCount(void *buffer, size_t bufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog);
+
+/*! Constructor and Destructor of FSE_CTable.
+ Note that FSE_CTable size depends on 'tableLog' and 'maxSymbolValue' */
+typedef unsigned FSE_CTable; /* don't allocate that. It's only meant to be more restrictive than void* */
+
+/*! FSE_compress_usingCTable():
+ Compress `src` using `ct` into `dst` which must be already allocated.
+ @return : size of compressed data (<= `dstCapacity`),
+ or 0 if compressed data could not fit into `dst`,
+ or an errorCode, which can be tested using FSE_isError() */
+FSE_PUBLIC_API size_t FSE_compress_usingCTable(void *dst, size_t dstCapacity, const void *src, size_t srcSize, const FSE_CTable *ct);
+
+/*!
+Tutorial :
+----------
+The first step is to count all symbols. FSE_count() does this job very fast.
+Result will be saved into 'count', a table of unsigned int, which must be already allocated, and have 'maxSymbolValuePtr[0]+1' cells.
+'src' is a table of bytes of size 'srcSize'. All values within 'src' MUST be <= maxSymbolValuePtr[0]
+maxSymbolValuePtr[0] will be updated, with its real value (necessarily <= original value)
+FSE_count() will return the number of occurrence of the most frequent symbol.
+This can be used to know if there is a single symbol within 'src', and to quickly evaluate its compressibility.
+If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()).
+
+The next step is to normalize the frequencies.
+FSE_normalizeCount() will ensure that sum of frequencies is == 2 ^'tableLog'.
+It also guarantees a minimum of 1 to any Symbol with frequency >= 1.
+You can use 'tableLog'==0 to mean "use default tableLog value".
+If you are unsure of which tableLog value to use, you can ask FSE_optimalTableLog(),
+which will provide the optimal valid tableLog given sourceSize, maxSymbolValue, and a user-defined maximum (0 means "default").
+
+The result of FSE_normalizeCount() will be saved into a table,
+called 'normalizedCounter', which is a table of signed short.
+'normalizedCounter' must be already allocated, and have at least 'maxSymbolValue+1' cells.
+The return value is tableLog if everything proceeded as expected.
+It is 0 if there is a single symbol within distribution.
+If there is an error (ex: invalid tableLog value), the function will return an ErrorCode (which can be tested using FSE_isError()).
+
+'normalizedCounter' can be saved in a compact manner to a memory area using FSE_writeNCount().
+'buffer' must be already allocated.
+For guaranteed success, buffer size must be at least FSE_headerBound().
+The result of the function is the number of bytes written into 'buffer'.
+If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError(); ex : buffer size too small).
+
+'normalizedCounter' can then be used to create the compression table 'CTable'.
+The space required by 'CTable' must be already allocated, using FSE_createCTable().
+You can then use FSE_buildCTable() to fill 'CTable'.
+If there is an error, both functions will return an ErrorCode (which can be tested using FSE_isError()).
+
+'CTable' can then be used to compress 'src', with FSE_compress_usingCTable().
+Similar to FSE_count(), the convention is that 'src' is assumed to be a table of char of size 'srcSize'
+The function returns the size of compressed data (without header), necessarily <= `dstCapacity`.
+If it returns '0', compressed data could not fit into 'dst'.
+If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()).
+*/
+
+/* *** DECOMPRESSION *** */
+
+/*! FSE_readNCount():
+ Read compactly saved 'normalizedCounter' from 'rBuffer'.
+ @return : size read from 'rBuffer',
+ or an errorCode, which can be tested using FSE_isError().
+ maxSymbolValuePtr[0] and tableLogPtr[0] will also be updated with their respective values */
+FSE_PUBLIC_API size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSymbolValuePtr, unsigned *tableLogPtr, const void *rBuffer, size_t rBuffSize);
+
+/*! Constructor and Destructor of FSE_DTable.
+ Note that its size depends on 'tableLog' */
+typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */
+
+/*! FSE_buildDTable():
+ Builds 'dt', which must be already allocated, using FSE_createDTable().
+ return : 0, or an errorCode, which can be tested using FSE_isError() */
+FSE_PUBLIC_API size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize);
+
+/*! FSE_decompress_usingDTable():
+ Decompress compressed source `cSrc` of size `cSrcSize` using `dt`
+ into `dst` which must be already allocated.
+ @return : size of regenerated data (necessarily <= `dstCapacity`),
+ or an errorCode, which can be tested using FSE_isError() */
+FSE_PUBLIC_API size_t FSE_decompress_usingDTable(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt);
+
+/*!
+Tutorial :
+----------
+(Note : these functions only decompress FSE-compressed blocks.
+ If block is uncompressed, use memcpy() instead
+ If block is a single repeated byte, use memset() instead )
+
+The first step is to obtain the normalized frequencies of symbols.
+This can be performed by FSE_readNCount() if it was saved using FSE_writeNCount().
+'normalizedCounter' must be already allocated, and have at least 'maxSymbolValuePtr[0]+1' cells of signed short.
+In practice, that means it's necessary to know 'maxSymbolValue' beforehand,
+or size the table to handle worst case situations (typically 256).
+FSE_readNCount() will provide 'tableLog' and 'maxSymbolValue'.
+The result of FSE_readNCount() is the number of bytes read from 'rBuffer'.
+Note that 'rBufferSize' must be at least 4 bytes, even if useful information is less than that.
+If there is an error, the function will return an error code, which can be tested using FSE_isError().
+
+The next step is to build the decompression tables 'FSE_DTable' from 'normalizedCounter'.
+This is performed by the function FSE_buildDTable().
+The space required by 'FSE_DTable' must be already allocated using FSE_createDTable().
+If there is an error, the function will return an error code, which can be tested using FSE_isError().
+
+`FSE_DTable` can then be used to decompress `cSrc`, with FSE_decompress_usingDTable().
+`cSrcSize` must be strictly correct, otherwise decompression will fail.
+FSE_decompress_usingDTable() result will tell how many bytes were regenerated (<=`dstCapacity`).
+If there is an error, the function will return an error code, which can be tested using FSE_isError(). (ex: dst buffer too small)
+*/
+
+/* *** Dependency *** */
+#include "bitstream.h"
+
+/* *****************************************
+* Static allocation
+*******************************************/
+/* FSE buffer bounds */
+#define FSE_NCOUNTBOUND 512
+#define FSE_BLOCKBOUND(size) (size + (size >> 7))
+#define FSE_COMPRESSBOUND(size) (FSE_NCOUNTBOUND + FSE_BLOCKBOUND(size)) /* Macro version, useful for static allocation */
+
+/* It is possible to statically allocate FSE CTable/DTable as a table of FSE_CTable/FSE_DTable using below macros */
+#define FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue) (1 + (1 << (maxTableLog - 1)) + ((maxSymbolValue + 1) * 2))
+#define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1 << maxTableLog))
+
+/* *****************************************
+* FSE advanced API
+*******************************************/
+/* FSE_count_wksp() :
+ * Same as FSE_count(), but using an externally provided scratch buffer.
+ * `workSpace` size must be table of >= `1024` unsigned
+ */
+size_t FSE_count_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace);
+
+/* FSE_countFast_wksp() :
+ * Same as FSE_countFast(), but using an externally provided scratch buffer.
+ * `workSpace` must be a table of minimum `1024` unsigned
+ */
+size_t FSE_countFast_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize, unsigned *workSpace);
+
+/*! FSE_count_simple
+ * Same as FSE_countFast(), but does not use any additional memory (not even on stack).
+ * This function is unsafe, and will segfault if any value within `src` is `> *maxSymbolValuePtr` (presuming it's also the size of `count`).
+*/
+size_t FSE_count_simple(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize);
+
+unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus);
+/**< same as FSE_optimalTableLog(), which used `minus==2` */
+
+size_t FSE_buildCTable_raw(FSE_CTable *ct, unsigned nbBits);
+/**< build a fake FSE_CTable, designed for a flat distribution, where each symbol uses nbBits */
+
+size_t FSE_buildCTable_rle(FSE_CTable *ct, unsigned char symbolValue);
+/**< build a fake FSE_CTable, designed to compress always the same symbolValue */
+
+/* FSE_buildCTable_wksp() :
+ * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`).
+ * `wkspSize` must be >= `(1<<tableLog)`.
+ */
+size_t FSE_buildCTable_wksp(FSE_CTable *ct, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, size_t wkspSize);
+
+size_t FSE_buildDTable_raw(FSE_DTable *dt, unsigned nbBits);
+/**< build a fake FSE_DTable, designed to read a flat distribution where each symbol uses nbBits */
+
+size_t FSE_buildDTable_rle(FSE_DTable *dt, unsigned char symbolValue);
+/**< build a fake FSE_DTable, designed to always generate the same symbolValue */
+
+size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize);
+/**< same as FSE_decompress(), using an externally allocated `workSpace` produced with `FSE_DTABLE_SIZE_U32(maxLog)` */
+
+/* *****************************************
+* FSE symbol compression API
+*******************************************/
+/*!
+ This API consists of small unitary functions, which highly benefit from being inlined.
+ Hence their body are included in next section.
+*/
+typedef struct {
+ ptrdiff_t value;
+ const void *stateTable;
+ const void *symbolTT;
+ unsigned stateLog;
+} FSE_CState_t;
+
+static void FSE_initCState(FSE_CState_t *CStatePtr, const FSE_CTable *ct);
+
+static void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *CStatePtr, unsigned symbol);
+
+static void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *CStatePtr);
+
+/**<
+These functions are inner components of FSE_compress_usingCTable().
+They allow the creation of custom streams, mixing multiple tables and bit sources.
+
+A key property to keep in mind is that encoding and decoding are done **in reverse direction**.
+So the first symbol you will encode is the last you will decode, like a LIFO stack.
+
+You will need a few variables to track your CStream. They are :
+
+FSE_CTable ct; // Provided by FSE_buildCTable()
+BIT_CStream_t bitStream; // bitStream tracking structure
+FSE_CState_t state; // State tracking structure (can have several)
+
+
+The first thing to do is to init bitStream and state.
+ size_t errorCode = BIT_initCStream(&bitStream, dstBuffer, maxDstSize);
+ FSE_initCState(&state, ct);
+
+Note that BIT_initCStream() can produce an error code, so its result should be tested, using FSE_isError();
+You can then encode your input data, byte after byte.
+FSE_encodeSymbol() outputs a maximum of 'tableLog' bits at a time.
+Remember decoding will be done in reverse direction.
+ FSE_encodeByte(&bitStream, &state, symbol);
+
+At any time, you can also add any bit sequence.
+Note : maximum allowed nbBits is 25, for compatibility with 32-bits decoders
+ BIT_addBits(&bitStream, bitField, nbBits);
+
+The above methods don't commit data to memory, they just store it into local register, for speed.
+Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t).
+Writing data to memory is a manual operation, performed by the flushBits function.
+ BIT_flushBits(&bitStream);
+
+Your last FSE encoding operation shall be to flush your last state value(s).
+ FSE_flushState(&bitStream, &state);
+
+Finally, you must close the bitStream.
+The function returns the size of CStream in bytes.
+If data couldn't fit into dstBuffer, it will return a 0 ( == not compressible)
+If there is an error, it returns an errorCode (which can be tested using FSE_isError()).
+ size_t size = BIT_closeCStream(&bitStream);
+*/
+
+/* *****************************************
+* FSE symbol decompression API
+*******************************************/
+typedef struct {
+ size_t state;
+ const void *table; /* precise table may vary, depending on U16 */
+} FSE_DState_t;
+
+static void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt);
+
+static unsigned char FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD);
+
+static unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr);
+
+/**<
+Let's now decompose FSE_decompress_usingDTable() into its unitary components.
+You will decode FSE-encoded symbols from the bitStream,
+and also any other bitFields you put in, **in reverse order**.
+
+You will need a few variables to track your bitStream. They are :
+
+BIT_DStream_t DStream; // Stream context
+FSE_DState_t DState; // State context. Multiple ones are possible
+FSE_DTable* DTablePtr; // Decoding table, provided by FSE_buildDTable()
+
+The first thing to do is to init the bitStream.
+ errorCode = BIT_initDStream(&DStream, srcBuffer, srcSize);
+
+You should then retrieve your initial state(s)
+(in reverse flushing order if you have several ones) :
+ errorCode = FSE_initDState(&DState, &DStream, DTablePtr);
+
+You can then decode your data, symbol after symbol.
+For information the maximum number of bits read by FSE_decodeSymbol() is 'tableLog'.
+Keep in mind that symbols are decoded in reverse order, like a LIFO stack (last in, first out).
+ unsigned char symbol = FSE_decodeSymbol(&DState, &DStream);
+
+You can retrieve any bitfield you eventually stored into the bitStream (in reverse order)
+Note : maximum allowed nbBits is 25, for 32-bits compatibility
+ size_t bitField = BIT_readBits(&DStream, nbBits);
+
+All above operations only read from local register (which size depends on size_t).
+Refueling the register from memory is manually performed by the reload method.
+ endSignal = FSE_reloadDStream(&DStream);
+
+BIT_reloadDStream() result tells if there is still some more data to read from DStream.
+BIT_DStream_unfinished : there is still some data left into the DStream.
+BIT_DStream_endOfBuffer : Dstream reached end of buffer. Its container may no longer be completely filled.
+BIT_DStream_completed : Dstream reached its exact end, corresponding in general to decompression completed.
+BIT_DStream_tooFar : Dstream went too far. Decompression result is corrupted.
+
+When reaching end of buffer (BIT_DStream_endOfBuffer), progress slowly, notably if you decode multiple symbols per loop,
+to properly detect the exact end of stream.
+After each decoded symbol, check if DStream is fully consumed using this simple test :
+ BIT_reloadDStream(&DStream) >= BIT_DStream_completed
+
+When it's done, verify decompression is fully completed, by checking both DStream and the relevant states.
+Checking if DStream has reached its end is performed by :
+ BIT_endOfDStream(&DStream);
+Check also the states. There might be some symbols left there, if some high probability ones (>50%) are possible.
+ FSE_endOfDState(&DState);
+*/
+
+/* *****************************************
+* FSE unsafe API
+*******************************************/
+static unsigned char FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD);
+/* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */
+
+/* *****************************************
+* Implementation of inlined functions
+*******************************************/
+typedef struct {
+ int deltaFindState;
+ U32 deltaNbBits;
+} FSE_symbolCompressionTransform; /* total 8 bytes */
+
+ZSTD_STATIC void FSE_initCState(FSE_CState_t *statePtr, const FSE_CTable *ct)
+{
+ const void *ptr = ct;
+ const U16 *u16ptr = (const U16 *)ptr;
+ const U32 tableLog = ZSTD_read16(ptr);
+ statePtr->value = (ptrdiff_t)1 << tableLog;
+ statePtr->stateTable = u16ptr + 2;
+ statePtr->symbolTT = ((const U32 *)ct + 1 + (tableLog ? (1 << (tableLog - 1)) : 1));
+ statePtr->stateLog = tableLog;
+}
+
+/*! FSE_initCState2() :
+* Same as FSE_initCState(), but the first symbol to include (which will be the last to be read)
+* uses the smallest state value possible, saving the cost of this symbol */
+ZSTD_STATIC void FSE_initCState2(FSE_CState_t *statePtr, const FSE_CTable *ct, U32 symbol)
+{
+ FSE_initCState(statePtr, ct);
+ {
+ const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol];
+ const U16 *stateTable = (const U16 *)(statePtr->stateTable);
+ U32 nbBitsOut = (U32)((symbolTT.deltaNbBits + (1 << 15)) >> 16);
+ statePtr->value = (nbBitsOut << 16) - symbolTT.deltaNbBits;
+ statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState];
+ }
+}
+
+ZSTD_STATIC void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *statePtr, U32 symbol)
+{
+ const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol];
+ const U16 *const stateTable = (const U16 *)(statePtr->stateTable);
+ U32 nbBitsOut = (U32)((statePtr->value + symbolTT.deltaNbBits) >> 16);
+ BIT_addBits(bitC, statePtr->value, nbBitsOut);
+ statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState];
+}
+
+ZSTD_STATIC void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *statePtr)
+{
+ BIT_addBits(bitC, statePtr->value, statePtr->stateLog);
+ BIT_flushBits(bitC);
+}
+
+/* ====== Decompression ====== */
+
+typedef struct {
+ U16 tableLog;
+ U16 fastMode;
+} FSE_DTableHeader; /* sizeof U32 */
+
+typedef struct {
+ unsigned short newState;
+ unsigned char symbol;
+ unsigned char nbBits;
+} FSE_decode_t; /* size == U32 */
+
+ZSTD_STATIC void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt)
+{
+ const void *ptr = dt;
+ const FSE_DTableHeader *const DTableH = (const FSE_DTableHeader *)ptr;
+ DStatePtr->state = BIT_readBits(bitD, DTableH->tableLog);
+ BIT_reloadDStream(bitD);
+ DStatePtr->table = dt + 1;
+}
+
+ZSTD_STATIC BYTE FSE_peekSymbol(const FSE_DState_t *DStatePtr)
+{
+ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
+ return DInfo.symbol;
+}
+
+ZSTD_STATIC void FSE_updateState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD)
+{
+ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
+ U32 const nbBits = DInfo.nbBits;
+ size_t const lowBits = BIT_readBits(bitD, nbBits);
+ DStatePtr->state = DInfo.newState + lowBits;
+}
+
+ZSTD_STATIC BYTE FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD)
+{
+ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
+ U32 const nbBits = DInfo.nbBits;
+ BYTE const symbol = DInfo.symbol;
+ size_t const lowBits = BIT_readBits(bitD, nbBits);
+
+ DStatePtr->state = DInfo.newState + lowBits;
+ return symbol;
+}
+
+/*! FSE_decodeSymbolFast() :
+ unsafe, only works if no symbol has a probability > 50% */
+ZSTD_STATIC BYTE FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD)
+{
+ FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state];
+ U32 const nbBits = DInfo.nbBits;
+ BYTE const symbol = DInfo.symbol;
+ size_t const lowBits = BIT_readBitsFast(bitD, nbBits);
+
+ DStatePtr->state = DInfo.newState + lowBits;
+ return symbol;
+}
+
+ZSTD_STATIC unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr) { return DStatePtr->state == 0; }
+
+/* **************************************************************
+* Tuning parameters
+****************************************************************/
+/*!MEMORY_USAGE :
+* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
+* Increasing memory usage improves compression ratio
+* Reduced memory usage can improve speed, due to cache effect
+* Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */
+#ifndef FSE_MAX_MEMORY_USAGE
+#define FSE_MAX_MEMORY_USAGE 14
+#endif
+#ifndef FSE_DEFAULT_MEMORY_USAGE
+#define FSE_DEFAULT_MEMORY_USAGE 13
+#endif
+
+/*!FSE_MAX_SYMBOL_VALUE :
+* Maximum symbol value authorized.
+* Required for proper stack allocation */
+#ifndef FSE_MAX_SYMBOL_VALUE
+#define FSE_MAX_SYMBOL_VALUE 255
+#endif
+
+/* **************************************************************
+* template functions type & suffix
+****************************************************************/
+#define FSE_FUNCTION_TYPE BYTE
+#define FSE_FUNCTION_EXTENSION
+#define FSE_DECODE_TYPE FSE_decode_t
+
+/* ***************************************************************
+* Constants
+*****************************************************************/
+#define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE - 2)
+#define FSE_MAX_TABLESIZE (1U << FSE_MAX_TABLELOG)
+#define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE - 1)
+#define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE - 2)
+#define FSE_MIN_TABLELOG 5
+
+#define FSE_TABLELOG_ABSOLUTE_MAX 15
+#if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX
+#error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported"
+#endif
+
+#define FSE_TABLESTEP(tableSize) ((tableSize >> 1) + (tableSize >> 3) + 3)
+
+#endif /* FSE_H */
diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c
new file mode 100644
index 0000000000..a84300e5a0
--- /dev/null
+++ b/lib/zstd/fse_decompress.c
@@ -0,0 +1,332 @@
+/*
+ * FSE : Finite State Entropy decoder
+ * Copyright (C) 2013-2015, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * 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").
+ *
+ * You can contact the author at :
+ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ */
+
+/* **************************************************************
+* Compiler specifics
+****************************************************************/
+#define FORCE_INLINE static __always_inline
+
+/* **************************************************************
+* Includes
+****************************************************************/
+#include "bitstream.h"
+#include "fse.h"
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/string.h> /* memcpy, memset */
+
+/* **************************************************************
+* Error Management
+****************************************************************/
+#define FSE_isError ERR_isError
+#define FSE_STATIC_ASSERT(c) \
+ { \
+ enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
+ } /* use only *after* variable declarations */
+
+/* check and forward error code */
+#define CHECK_F(f) \
+ { \
+ size_t const e = f; \
+ if (FSE_isError(e)) \
+ return e; \
+ }
+
+/* **************************************************************
+* Templates
+****************************************************************/
+/*
+ designed to be included
+ for type-specific functions (template emulation in C)
+ Objective is to write these functions only once, for improved maintenance
+*/
+
+/* safety checks */
+#ifndef FSE_FUNCTION_EXTENSION
+#error "FSE_FUNCTION_EXTENSION must be defined"
+#endif
+#ifndef FSE_FUNCTION_TYPE
+#error "FSE_FUNCTION_TYPE must be defined"
+#endif
+
+/* Function names */
+#define FSE_CAT(X, Y) X##Y
+#define FSE_FUNCTION_NAME(X, Y) FSE_CAT(X, Y)
+#define FSE_TYPE_NAME(X, Y) FSE_CAT(X, Y)
+
+/* Function templates */
+
+size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize)
+{
+ void *const tdPtr = dt + 1; /* because *dt is unsigned, 32-bits aligned on 32-bits */
+ FSE_DECODE_TYPE *const tableDecode = (FSE_DECODE_TYPE *)(tdPtr);
+ U16 *symbolNext = (U16 *)workspace;
+
+ U32 const maxSV1 = maxSymbolValue + 1;
+ U32 const tableSize = 1 << tableLog;
+ U32 highThreshold = tableSize - 1;
+
+ /* Sanity Checks */
+ if (workspaceSize < sizeof(U16) * (FSE_MAX_SYMBOL_VALUE + 1))
+ return ERROR(tableLog_tooLarge);
+ if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE)
+ return ERROR(maxSymbolValue_tooLarge);
+ if (tableLog > FSE_MAX_TABLELOG)
+ return ERROR(tableLog_tooLarge);
+
+ /* Init, lay down lowprob symbols */
+ {
+ FSE_DTableHeader DTableH;
+ DTableH.tableLog = (U16)tableLog;
+ DTableH.fastMode = 1;
+ {
+ S16 const largeLimit = (S16)(1 << (tableLog - 1));
+ U32 s;
+ for (s = 0; s < maxSV1; s++) {
+ if (normalizedCounter[s] == -1) {
+ tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s;
+ symbolNext[s] = 1;
+ } else {
+ if (normalizedCounter[s] >= largeLimit)
+ DTableH.fastMode = 0;
+ symbolNext[s] = normalizedCounter[s];
+ }
+ }
+ }
+ memcpy(dt, &DTableH, sizeof(DTableH));
+ }
+
+ /* Spread symbols */
+ {
+ U32 const tableMask = tableSize - 1;
+ U32 const step = FSE_TABLESTEP(tableSize);
+ U32 s, position = 0;
+ for (s = 0; s < maxSV1; s++) {
+ int i;
+ for (i = 0; i < normalizedCounter[s]; i++) {
+ tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s;
+ position = (position + step) & tableMask;
+ while (position > highThreshold)
+ position = (position + step) & tableMask; /* lowprob area */
+ }
+ }
+ if (position != 0)
+ return ERROR(GENERIC); /* position must reach all cells once, otherwise normalizedCounter is incorrect */
+ }
+
+ /* Build Decoding table */
+ {
+ U32 u;
+ for (u = 0; u < tableSize; u++) {
+ FSE_FUNCTION_TYPE const symbol = (FSE_FUNCTION_TYPE)(tableDecode[u].symbol);
+ U16 nextState = symbolNext[symbol]++;
+ tableDecode[u].nbBits = (BYTE)(tableLog - BIT_highbit32((U32)nextState));
+ tableDecode[u].newState = (U16)((nextState << tableDecode[u].nbBits) - tableSize);
+ }
+ }
+
+ return 0;
+}
+
+/*-*******************************************************
+* Decompression (Byte symbols)
+*********************************************************/
+size_t FSE_buildDTable_rle(FSE_DTable *dt, BYTE symbolValue)
+{
+ void *ptr = dt;
+ FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr;
+ void *dPtr = dt + 1;
+ FSE_decode_t *const cell = (FSE_decode_t *)dPtr;
+
+ DTableH->tableLog = 0;
+ DTableH->fastMode = 0;
+
+ cell->newState = 0;
+ cell->symbol = symbolValue;
+ cell->nbBits = 0;
+
+ return 0;
+}
+
+size_t FSE_buildDTable_raw(FSE_DTable *dt, unsigned nbBits)
+{
+ void *ptr = dt;
+ FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr;
+ void *dPtr = dt + 1;
+ FSE_decode_t *const dinfo = (FSE_decode_t *)dPtr;
+ const unsigned tableSize = 1 << nbBits;
+ const unsigned tableMask = tableSize - 1;
+ const unsigned maxSV1 = tableMask + 1;
+ unsigned s;
+
+ /* Sanity checks */
+ if (nbBits < 1)
+ return ERROR(GENERIC); /* min size */
+
+ /* Build Decoding Table */
+ DTableH->tableLog = (U16)nbBits;
+ DTableH->fastMode = 1;
+ for (s = 0; s < maxSV1; s++) {
+ dinfo[s].newState = 0;
+ dinfo[s].symbol = (BYTE)s;
+ dinfo[s].nbBits = (BYTE)nbBits;
+ }
+
+ return 0;
+}
+
+FORCE_INLINE size_t FSE_decompress_usingDTable_generic(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt,
+ const unsigned fast)
+{
+ BYTE *const ostart = (BYTE *)dst;
+ BYTE *op = ostart;
+ BYTE *const omax = op + maxDstSize;
+ BYTE *const olimit = omax - 3;
+
+ BIT_DStream_t bitD;
+ FSE_DState_t state1;
+ FSE_DState_t state2;
+
+ /* Init */
+ CHECK_F(BIT_initDStream(&bitD, cSrc, cSrcSize));
+
+ FSE_initDState(&state1, &bitD, dt);
+ FSE_initDState(&state2, &bitD, dt);
+
+#define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD)
+
+ /* 4 symbols per loop */
+ for (; (BIT_reloadDStream(&bitD) == BIT_DStream_unfinished) & (op < olimit); op += 4) {
+ op[0] = FSE_GETSYMBOL(&state1);
+
+ if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */
+ BIT_reloadDStream(&bitD);
+
+ op[1] = FSE_GETSYMBOL(&state2);
+
+ if (FSE_MAX_TABLELOG * 4 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */
+ {
+ if (BIT_reloadDStream(&bitD) > BIT_DStream_unfinished) {
+ op += 2;
+ break;
+ }
+ }
+
+ op[2] = FSE_GETSYMBOL(&state1);
+
+ if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */
+ BIT_reloadDStream(&bitD);
+
+ op[3] = FSE_GETSYMBOL(&state2);
+ }
+
+ /* tail */
+ /* note : BIT_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly BIT_DStream_completed */
+ while (1) {
+ if (op > (omax - 2))
+ return ERROR(dstSize_tooSmall);
+ *op++ = FSE_GETSYMBOL(&state1);
+ if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) {
+ *op++ = FSE_GETSYMBOL(&state2);
+ break;
+ }
+
+ if (op > (omax - 2))
+ return ERROR(dstSize_tooSmall);
+ *op++ = FSE_GETSYMBOL(&state2);
+ if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) {
+ *op++ = FSE_GETSYMBOL(&state1);
+ break;
+ }
+ }
+
+ return op - ostart;
+}
+
+size_t FSE_decompress_usingDTable(void *dst, size_t originalSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt)
+{
+ const void *ptr = dt;
+ const FSE_DTableHeader *DTableH = (const FSE_DTableHeader *)ptr;
+ const U32 fastMode = DTableH->fastMode;
+
+ /* select fast mode (static) */
+ if (fastMode)
+ return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1);
+ return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0);
+}
+
+size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize)
+{
+ const BYTE *const istart = (const BYTE *)cSrc;
+ const BYTE *ip = istart;
+ unsigned tableLog;
+ unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE;
+ size_t NCountLength;
+
+ FSE_DTable *dt;
+ short *counting;
+ size_t spaceUsed32 = 0;
+
+ FSE_STATIC_ASSERT(sizeof(FSE_DTable) == sizeof(U32));
+
+ dt = (FSE_DTable *)((U32 *)workspace + spaceUsed32);
+ spaceUsed32 += FSE_DTABLE_SIZE_U32(maxLog);
+ counting = (short *)((U32 *)workspace + spaceUsed32);
+ spaceUsed32 += ALIGN(sizeof(short) * (FSE_MAX_SYMBOL_VALUE + 1), sizeof(U32)) >> 2;
+
+ if ((spaceUsed32 << 2) > workspaceSize)
+ return ERROR(tableLog_tooLarge);
+ workspace = (U32 *)workspace + spaceUsed32;
+ workspaceSize -= (spaceUsed32 << 2);
+
+ /* normal FSE decoding mode */
+ NCountLength = FSE_readNCount(counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
+ if (FSE_isError(NCountLength))
+ return NCountLength;
+ // if (NCountLength >= cSrcSize) return ERROR(srcSize_wrong); /* too small input size; supposed to be already checked in NCountLength, only remaining
+ // case : NCountLength==cSrcSize */
+ if (tableLog > maxLog)
+ return ERROR(tableLog_tooLarge);
+ ip += NCountLength;
+ cSrcSize -= NCountLength;
+
+ CHECK_F(FSE_buildDTable_wksp(dt, counting, maxSymbolValue, tableLog, workspace, workspaceSize));
+
+ return FSE_decompress_usingDTable(dst, dstCapacity, ip, cSrcSize, dt); /* always return, even if it is an error code */
+}
diff --git a/lib/zstd/huf.h b/lib/zstd/huf.h
new file mode 100644
index 0000000000..2143da28d9
--- /dev/null
+++ b/lib/zstd/huf.h
@@ -0,0 +1,212 @@
+/*
+ * Huffman coder, part of New Generation Entropy library
+ * header file
+ * Copyright (C) 2013-2016, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * 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").
+ *
+ * You can contact the author at :
+ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ */
+#ifndef HUF_H_298734234
+#define HUF_H_298734234
+
+/* *** Dependencies *** */
+#include <linux/types.h> /* size_t */
+
+/* *** Tool functions *** */
+#define HUF_BLOCKSIZE_MAX (128 * 1024) /**< maximum input size for a single block compressed with HUF_compress */
+size_t HUF_compressBound(size_t size); /**< maximum compressed size (worst case) */
+
+/* Error Management */
+unsigned HUF_isError(size_t code); /**< tells if a return value is an error code */
+
+/* *** Advanced function *** */
+
+/** HUF_compress4X_wksp() :
+* Same as HUF_compress2(), but uses externally allocated `workSpace`, which must be a table of >= 1024 unsigned */
+size_t HUF_compress4X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
+ size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
+
+/* *** Dependencies *** */
+#include "mem.h" /* U32 */
+
+/* *** Constants *** */
+#define HUF_TABLELOG_MAX 12 /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */
+#define HUF_TABLELOG_DEFAULT 11 /* tableLog by default, when not specified */
+#define HUF_SYMBOLVALUE_MAX 255
+
+#define HUF_TABLELOG_ABSOLUTEMAX 15 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
+#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX)
+#error "HUF_TABLELOG_MAX is too large !"
+#endif
+
+/* ****************************************
+* Static allocation
+******************************************/
+/* HUF buffer bounds */
+#define HUF_CTABLEBOUND 129
+#define HUF_BLOCKBOUND(size) (size + (size >> 8) + 8) /* only true if incompressible pre-filtered with fast heuristic */
+#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */
+
+/* static allocation of HUF's Compression Table */
+#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \
+ U32 name##hb[maxSymbolValue + 1]; \
+ void *name##hv = &(name##hb); \
+ HUF_CElt *name = (HUF_CElt *)(name##hv) /* no final ; */
+
+/* static allocation of HUF's DTable */
+typedef U32 HUF_DTable;
+#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1 << (maxTableLog)))
+#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = {((U32)((maxTableLog)-1) * 0x01000001)}
+#define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = {((U32)(maxTableLog)*0x01000001)}
+
+/* The workspace must have alignment at least 4 and be at least this large */
+#define HUF_COMPRESS_WORKSPACE_SIZE (6 << 10)
+#define HUF_COMPRESS_WORKSPACE_SIZE_U32 (HUF_COMPRESS_WORKSPACE_SIZE / sizeof(U32))
+
+/* The workspace must have alignment at least 4 and be at least this large */
+#define HUF_DECOMPRESS_WORKSPACE_SIZE (3 << 10)
+#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32))
+
+/* ****************************************
+* Advanced decompression functions
+******************************************/
+size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); /**< decodes RLE and uncompressed */
+size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
+ size_t workspaceSize); /**< considers RLE and uncompressed as errors */
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
+ size_t workspaceSize); /**< single-symbol decoder */
+size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
+ size_t workspaceSize); /**< double-symbols decoder */
+
+/* ****************************************
+* HUF detailed API
+******************************************/
+/*!
+HUF_compress() does the following:
+1. count symbol occurrence from source[] into table count[] using FSE_count()
+2. (optional) refine tableLog using HUF_optimalTableLog()
+3. build Huffman table from count using HUF_buildCTable()
+4. save Huffman table to memory buffer using HUF_writeCTable_wksp()
+5. encode the data stream using HUF_compress4X_usingCTable()
+
+The following API allows targeting specific sub-functions for advanced tasks.
+For example, it's possible to compress several blocks using the same 'CTable',
+or to save and regenerate 'CTable' using external methods.
+*/
+/* FSE_count() : find it within "fse.h" */
+unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue);
+typedef struct HUF_CElt_s HUF_CElt; /* incomplete type */
+size_t HUF_writeCTable_wksp(void *dst, size_t maxDstSize, const HUF_CElt *CTable, unsigned maxSymbolValue, unsigned huffLog, void *workspace, size_t workspaceSize);
+size_t HUF_compress4X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable);
+
+typedef enum {
+ HUF_repeat_none, /**< Cannot use the previous table */
+ HUF_repeat_check, /**< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1,
+ 4}X_repeat */
+ HUF_repeat_valid /**< Can use the previous table and it is asumed to be valid */
+} HUF_repeat;
+/** HUF_compress4X_repeat() :
+* Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
+* If it uses hufTable it does not modify hufTable or repeat.
+* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
+* If preferRepeat then the old table will always be used if valid. */
+size_t HUF_compress4X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
+ size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat,
+ int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
+
+/** HUF_buildCTable_wksp() :
+ * Same as HUF_buildCTable(), but using externally allocated scratch buffer.
+ * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of 1024 unsigned.
+ */
+size_t HUF_buildCTable_wksp(HUF_CElt *tree, const U32 *count, U32 maxSymbolValue, U32 maxNbBits, void *workSpace, size_t wkspSize);
+
+/*! HUF_readStats() :
+ Read compact Huffman tree, saved by HUF_writeCTable().
+ `huffWeight` is destination buffer.
+ @return : size read from `src` , or an error Code .
+ Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */
+size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize,
+ void *workspace, size_t workspaceSize);
+
+/** HUF_readCTable() :
+* Loading a CTable saved with HUF_writeCTable() */
+size_t HUF_readCTable_wksp(HUF_CElt *CTable, unsigned maxSymbolValue, const void *src, size_t srcSize, void *workspace, size_t workspaceSize);
+
+/*
+HUF_decompress() does the following:
+1. select the decompression algorithm (X2, X4) based on pre-computed heuristics
+2. build Huffman table from save, using HUF_readDTableXn()
+3. decode 1 or 4 segments in parallel using HUF_decompressSXn_usingDTable
+*/
+
+/** HUF_selectDecoder() :
+* Tells which decoder is likely to decode faster,
+* based on a set of pre-determined metrics.
+* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 .
+* Assumption : 0 < cSrcSize < dstSize <= 128 KB */
+U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize);
+
+size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize);
+size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize);
+
+size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
+size_t HUF_decompress4X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
+size_t HUF_decompress4X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
+
+/* single stream variants */
+
+size_t HUF_compress1X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
+ size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
+size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable);
+/** HUF_compress1X_repeat() :
+* Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
+* If it uses hufTable it does not modify hufTable or repeat.
+* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
+* If preferRepeat then the old table will always be used if valid. */
+size_t HUF_compress1X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace,
+ size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat,
+ int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */
+
+size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize);
+size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
+ size_t workspaceSize); /**< single-symbol decoder */
+size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace,
+ size_t workspaceSize); /**< double-symbols decoder */
+
+size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize,
+ const HUF_DTable *DTable); /**< automatic selection of sing or double symbol decoder, based on DTable */
+size_t HUF_decompress1X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
+size_t HUF_decompress1X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable);
+
+#endif /* HUF_H_298734234 */
diff --git a/lib/zstd/huf_decompress.c b/lib/zstd/huf_decompress.c
new file mode 100644
index 0000000000..6526482047
--- /dev/null
+++ b/lib/zstd/huf_decompress.c
@@ -0,0 +1,960 @@
+/*
+ * Huffman decoder, part of New Generation Entropy library
+ * Copyright (C) 2013-2016, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * 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").
+ *
+ * You can contact the author at :
+ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ */
+
+/* **************************************************************
+* Compiler specifics
+****************************************************************/
+#define FORCE_INLINE static __always_inline
+
+/* **************************************************************
+* Dependencies
+****************************************************************/
+#include "bitstream.h" /* BIT_* */
+#include "fse.h" /* header compression */
+#include "huf.h"
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/string.h> /* memcpy, memset */
+
+/* **************************************************************
+* Error Management
+****************************************************************/
+#define HUF_STATIC_ASSERT(c) \
+ { \
+ enum { HUF_static_assert = 1 / (int)(!!(c)) }; \
+ } /* use only *after* variable declarations */
+
+/*-***************************/
+/* generic DTableDesc */
+/*-***************************/
+
+typedef struct {
+ BYTE maxTableLog;
+ BYTE tableType;
+ BYTE tableLog;
+ BYTE reserved;
+} DTableDesc;
+
+static DTableDesc HUF_getDTableDesc(const HUF_DTable *table)
+{
+ DTableDesc dtd;
+ memcpy(&dtd, table, sizeof(dtd));
+ return dtd;
+}
+
+/*-***************************/
+/* single-symbol decoding */
+/*-***************************/
+
+typedef struct {
+ BYTE byte;
+ BYTE nbBits;
+} HUF_DEltX2; /* single-symbol decoding */
+
+size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
+{
+ U32 tableLog = 0;
+ U32 nbSymbols = 0;
+ size_t iSize;
+ void *const dtPtr = DTable + 1;
+ HUF_DEltX2 *const dt = (HUF_DEltX2 *)dtPtr;
+
+ U32 *rankVal;
+ BYTE *huffWeight;
+ size_t spaceUsed32 = 0;
+
+ rankVal = (U32 *)workspace + spaceUsed32;
+ spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1;
+ huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32);
+ spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
+
+ if ((spaceUsed32 << 2) > workspaceSize)
+ return ERROR(tableLog_tooLarge);
+ workspace = (U32 *)workspace + spaceUsed32;
+ workspaceSize -= (spaceUsed32 << 2);
+
+ HUF_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable));
+ /* memset(huffWeight, 0, sizeof(huffWeight)); */ /* is not necessary, even though some analyzer complain ... */
+
+ iSize = HUF_readStats_wksp(huffWeight, HUF_SYMBOLVALUE_MAX + 1, rankVal, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize);
+ if (HUF_isError(iSize))
+ return iSize;
+
+ /* Table header */
+ {
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (tableLog > (U32)(dtd.maxTableLog + 1))
+ return ERROR(tableLog_tooLarge); /* DTable too small, Huffman tree cannot fit in */
+ dtd.tableType = 0;
+ dtd.tableLog = (BYTE)tableLog;
+ memcpy(DTable, &dtd, sizeof(dtd));
+ }
+
+ /* Calculate starting value for each rank */
+ {
+ U32 n, nextRankStart = 0;
+ for (n = 1; n < tableLog + 1; n++) {
+ U32 const curr = nextRankStart;
+ nextRankStart += (rankVal[n] << (n - 1));
+ rankVal[n] = curr;
+ }
+ }
+
+ /* fill DTable */
+ {
+ U32 n;
+ for (n = 0; n < nbSymbols; n++) {
+ U32 const w = huffWeight[n];
+ U32 const length = (1 << w) >> 1;
+ U32 u;
+ HUF_DEltX2 D;
+ D.byte = (BYTE)n;
+ D.nbBits = (BYTE)(tableLog + 1 - w);
+ for (u = rankVal[w]; u < rankVal[w] + length; u++)
+ dt[u] = D;
+ rankVal[w] += length;
+ }
+ }
+
+ return iSize;
+}
+
+static BYTE HUF_decodeSymbolX2(BIT_DStream_t *Dstream, const HUF_DEltX2 *dt, const U32 dtLog)
+{
+ size_t const val = BIT_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */
+ BYTE const c = dt[val].byte;
+ BIT_skipBits(Dstream, dt[val].nbBits);
+ return c;
+}
+
+#define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) *ptr++ = HUF_decodeSymbolX2(DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \
+ if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \
+ HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
+
+#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \
+ if (ZSTD_64bits()) \
+ HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
+
+FORCE_INLINE size_t HUF_decodeStreamX2(BYTE *p, BIT_DStream_t *const bitDPtr, BYTE *const pEnd, const HUF_DEltX2 *const dt, const U32 dtLog)
+{
+ BYTE *const pStart = p;
+
+ /* up to 4 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p <= pEnd - 4)) {
+ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_1(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ }
+
+ /* closer to the end */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p < pEnd))
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+
+ /* no more data to retrieve from bitstream, hence no need to reload */
+ while (p < pEnd)
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+
+ return pEnd - pStart;
+}
+
+static size_t HUF_decompress1X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ BYTE *op = (BYTE *)dst;
+ BYTE *const oend = op + dstSize;
+ const void *dtPtr = DTable + 1;
+ const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr;
+ BIT_DStream_t bitD;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ U32 const dtLog = dtd.tableLog;
+
+ {
+ size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+
+ HUF_decodeStreamX2(op, &bitD, oend, dt, dtLog);
+
+ /* check */
+ if (!BIT_endOfDStream(&bitD))
+ return ERROR(corruption_detected);
+
+ return dstSize;
+}
+
+size_t HUF_decompress1X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 0)
+ return ERROR(GENERIC);
+ return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ const BYTE *ip = (const BYTE *)cSrc;
+
+ size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize);
+ if (HUF_isError(hSize))
+ return hSize;
+ if (hSize >= cSrcSize)
+ return ERROR(srcSize_wrong);
+ ip += hSize;
+ cSrcSize -= hSize;
+
+ return HUF_decompress1X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx);
+}
+
+static size_t HUF_decompress4X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ /* Check */
+ if (cSrcSize < 10)
+ return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
+
+ {
+ const BYTE *const istart = (const BYTE *)cSrc;
+ BYTE *const ostart = (BYTE *)dst;
+ BYTE *const oend = ostart + dstSize;
+ const void *const dtPtr = DTable + 1;
+ const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr;
+
+ /* Init */
+ BIT_DStream_t bitD1;
+ BIT_DStream_t bitD2;
+ BIT_DStream_t bitD3;
+ BIT_DStream_t bitD4;
+ size_t const length1 = ZSTD_readLE16(istart);
+ size_t const length2 = ZSTD_readLE16(istart + 2);
+ size_t const length3 = ZSTD_readLE16(istart + 4);
+ size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6);
+ const BYTE *const istart1 = istart + 6; /* jumpTable */
+ const BYTE *const istart2 = istart1 + length1;
+ const BYTE *const istart3 = istart2 + length2;
+ const BYTE *const istart4 = istart3 + length3;
+ const size_t segmentSize = (dstSize + 3) / 4;
+ BYTE *const opStart2 = ostart + segmentSize;
+ BYTE *const opStart3 = opStart2 + segmentSize;
+ BYTE *const opStart4 = opStart3 + segmentSize;
+ BYTE *op1 = ostart;
+ BYTE *op2 = opStart2;
+ BYTE *op3 = opStart3;
+ BYTE *op4 = opStart4;
+ U32 endSignal;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ U32 const dtLog = dtd.tableLog;
+
+ if (length4 > cSrcSize)
+ return ERROR(corruption_detected); /* overflow */
+ {
+ size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+
+ /* 16-32 symbols per loop (4-8 symbols per stream) */
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ for (; (endSignal == BIT_DStream_unfinished) && (op4 < (oend - 7));) {
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ }
+
+ /* check corruption */
+ if (op1 > opStart2)
+ return ERROR(corruption_detected);
+ if (op2 > opStart3)
+ return ERROR(corruption_detected);
+ if (op3 > opStart4)
+ return ERROR(corruption_detected);
+ /* note : op4 supposed already verified within main loop */
+
+ /* finish bitStreams one by one */
+ HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog);
+ HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog);
+ HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog);
+ HUF_decodeStreamX2(op4, &bitD4, oend, dt, dtLog);
+
+ /* check */
+ endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
+ if (!endSignal)
+ return ERROR(corruption_detected);
+
+ /* decoded size */
+ return dstSize;
+ }
+}
+
+size_t HUF_decompress4X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 0)
+ return ERROR(GENERIC);
+ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ const BYTE *ip = (const BYTE *)cSrc;
+
+ size_t const hSize = HUF_readDTableX2_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize);
+ if (HUF_isError(hSize))
+ return hSize;
+ if (hSize >= cSrcSize)
+ return ERROR(srcSize_wrong);
+ ip += hSize;
+ cSrcSize -= hSize;
+
+ return HUF_decompress4X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
+}
+
+/* *************************/
+/* double-symbols decoding */
+/* *************************/
+typedef struct {
+ U16 sequence;
+ BYTE nbBits;
+ BYTE length;
+} HUF_DEltX4; /* double-symbols decoding */
+
+typedef struct {
+ BYTE symbol;
+ BYTE weight;
+} sortedSymbol_t;
+
+/* HUF_fillDTableX4Level2() :
+ * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */
+static void HUF_fillDTableX4Level2(HUF_DEltX4 *DTable, U32 sizeLog, const U32 consumed, const U32 *rankValOrigin, const int minWeight,
+ const sortedSymbol_t *sortedSymbols, const U32 sortedListSize, U32 nbBitsBaseline, U16 baseSeq)
+{
+ HUF_DEltX4 DElt;
+ U32 rankVal[HUF_TABLELOG_MAX + 1];
+
+ /* get pre-calculated rankVal */
+ memcpy(rankVal, rankValOrigin, sizeof(rankVal));
+
+ /* fill skipped values */
+ if (minWeight > 1) {
+ U32 i, skipSize = rankVal[minWeight];
+ ZSTD_writeLE16(&(DElt.sequence), baseSeq);
+ DElt.nbBits = (BYTE)(consumed);
+ DElt.length = 1;
+ for (i = 0; i < skipSize; i++)
+ DTable[i] = DElt;
+ }
+
+ /* fill DTable */
+ {
+ U32 s;
+ for (s = 0; s < sortedListSize; s++) { /* note : sortedSymbols already skipped */
+ const U32 symbol = sortedSymbols[s].symbol;
+ const U32 weight = sortedSymbols[s].weight;
+ const U32 nbBits = nbBitsBaseline - weight;
+ const U32 length = 1 << (sizeLog - nbBits);
+ const U32 start = rankVal[weight];
+ U32 i = start;
+ const U32 end = start + length;
+
+ ZSTD_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8)));
+ DElt.nbBits = (BYTE)(nbBits + consumed);
+ DElt.length = 2;
+ do {
+ DTable[i++] = DElt;
+ } while (i < end); /* since length >= 1 */
+
+ rankVal[weight] += length;
+ }
+ }
+}
+
+typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1];
+typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1];
+
+static void HUF_fillDTableX4(HUF_DEltX4 *DTable, const U32 targetLog, const sortedSymbol_t *sortedList, const U32 sortedListSize, const U32 *rankStart,
+ rankVal_t rankValOrigin, const U32 maxWeight, const U32 nbBitsBaseline)
+{
+ U32 rankVal[HUF_TABLELOG_MAX + 1];
+ const int scaleLog = nbBitsBaseline - targetLog; /* note : targetLog >= srcLog, hence scaleLog <= 1 */
+ const U32 minBits = nbBitsBaseline - maxWeight;
+ U32 s;
+
+ memcpy(rankVal, rankValOrigin, sizeof(rankVal));
+
+ /* fill DTable */
+ for (s = 0; s < sortedListSize; s++) {
+ const U16 symbol = sortedList[s].symbol;
+ const U32 weight = sortedList[s].weight;
+ const U32 nbBits = nbBitsBaseline - weight;
+ const U32 start = rankVal[weight];
+ const U32 length = 1 << (targetLog - nbBits);
+
+ if (targetLog - nbBits >= minBits) { /* enough room for a second symbol */
+ U32 sortedRank;
+ int minWeight = nbBits + scaleLog;
+ if (minWeight < 1)
+ minWeight = 1;
+ sortedRank = rankStart[minWeight];
+ HUF_fillDTableX4Level2(DTable + start, targetLog - nbBits, nbBits, rankValOrigin[nbBits], minWeight, sortedList + sortedRank,
+ sortedListSize - sortedRank, nbBitsBaseline, symbol);
+ } else {
+ HUF_DEltX4 DElt;
+ ZSTD_writeLE16(&(DElt.sequence), symbol);
+ DElt.nbBits = (BYTE)(nbBits);
+ DElt.length = 1;
+ {
+ U32 const end = start + length;
+ U32 u;
+ for (u = start; u < end; u++)
+ DTable[u] = DElt;
+ }
+ }
+ rankVal[weight] += length;
+ }
+}
+
+size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize)
+{
+ U32 tableLog, maxW, sizeOfSort, nbSymbols;
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ U32 const maxTableLog = dtd.maxTableLog;
+ size_t iSize;
+ void *dtPtr = DTable + 1; /* force compiler to avoid strict-aliasing */
+ HUF_DEltX4 *const dt = (HUF_DEltX4 *)dtPtr;
+ U32 *rankStart;
+
+ rankValCol_t *rankVal;
+ U32 *rankStats;
+ U32 *rankStart0;
+ sortedSymbol_t *sortedSymbol;
+ BYTE *weightList;
+ size_t spaceUsed32 = 0;
+
+ HUF_STATIC_ASSERT((sizeof(rankValCol_t) & 3) == 0);
+
+ rankVal = (rankValCol_t *)((U32 *)workspace + spaceUsed32);
+ spaceUsed32 += (sizeof(rankValCol_t) * HUF_TABLELOG_MAX) >> 2;
+ rankStats = (U32 *)workspace + spaceUsed32;
+ spaceUsed32 += HUF_TABLELOG_MAX + 1;
+ rankStart0 = (U32 *)workspace + spaceUsed32;
+ spaceUsed32 += HUF_TABLELOG_MAX + 2;
+ sortedSymbol = (sortedSymbol_t *)((U32 *)workspace + spaceUsed32);
+ spaceUsed32 += ALIGN(sizeof(sortedSymbol_t) * (HUF_SYMBOLVALUE_MAX + 1), sizeof(U32)) >> 2;
+ weightList = (BYTE *)((U32 *)workspace + spaceUsed32);
+ spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2;
+
+ if ((spaceUsed32 << 2) > workspaceSize)
+ return ERROR(tableLog_tooLarge);
+ workspace = (U32 *)workspace + spaceUsed32;
+ workspaceSize -= (spaceUsed32 << 2);
+
+ rankStart = rankStart0 + 1;
+ memset(rankStats, 0, sizeof(U32) * (2 * HUF_TABLELOG_MAX + 2 + 1));
+
+ HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable)); /* if compiler fails here, assertion is wrong */
+ if (maxTableLog > HUF_TABLELOG_MAX)
+ return ERROR(tableLog_tooLarge);
+ /* memset(weightList, 0, sizeof(weightList)); */ /* is not necessary, even though some analyzer complain ... */
+
+ iSize = HUF_readStats_wksp(weightList, HUF_SYMBOLVALUE_MAX + 1, rankStats, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize);
+ if (HUF_isError(iSize))
+ return iSize;
+
+ /* check result */
+ if (tableLog > maxTableLog)
+ return ERROR(tableLog_tooLarge); /* DTable can't fit code depth */
+
+ /* find maxWeight */
+ for (maxW = tableLog; rankStats[maxW] == 0; maxW--) {
+ } /* necessarily finds a solution before 0 */
+
+ /* Get start index of each weight */
+ {
+ U32 w, nextRankStart = 0;
+ for (w = 1; w < maxW + 1; w++) {
+ U32 curr = nextRankStart;
+ nextRankStart += rankStats[w];
+ rankStart[w] = curr;
+ }
+ rankStart[0] = nextRankStart; /* put all 0w symbols at the end of sorted list*/
+ sizeOfSort = nextRankStart;
+ }
+
+ /* sort symbols by weight */
+ {
+ U32 s;
+ for (s = 0; s < nbSymbols; s++) {
+ U32 const w = weightList[s];
+ U32 const r = rankStart[w]++;
+ sortedSymbol[r].symbol = (BYTE)s;
+ sortedSymbol[r].weight = (BYTE)w;
+ }
+ rankStart[0] = 0; /* forget 0w symbols; this is beginning of weight(1) */
+ }
+
+ /* Build rankVal */
+ {
+ U32 *const rankVal0 = rankVal[0];
+ {
+ int const rescale = (maxTableLog - tableLog) - 1; /* tableLog <= maxTableLog */
+ U32 nextRankVal = 0;
+ U32 w;
+ for (w = 1; w < maxW + 1; w++) {
+ U32 curr = nextRankVal;
+ nextRankVal += rankStats[w] << (w + rescale);
+ rankVal0[w] = curr;
+ }
+ }
+ {
+ U32 const minBits = tableLog + 1 - maxW;
+ U32 consumed;
+ for (consumed = minBits; consumed < maxTableLog - minBits + 1; consumed++) {
+ U32 *const rankValPtr = rankVal[consumed];
+ U32 w;
+ for (w = 1; w < maxW + 1; w++) {
+ rankValPtr[w] = rankVal0[w] >> consumed;
+ }
+ }
+ }
+ }
+
+ HUF_fillDTableX4(dt, maxTableLog, sortedSymbol, sizeOfSort, rankStart0, rankVal, maxW, tableLog + 1);
+
+ dtd.tableLog = (BYTE)maxTableLog;
+ dtd.tableType = 1;
+ memcpy(DTable, &dtd, sizeof(dtd));
+ return iSize;
+}
+
+static U32 HUF_decodeSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog)
+{
+ size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
+ memcpy(op, dt + val, 2);
+ BIT_skipBits(DStream, dt[val].nbBits);
+ return dt[val].length;
+}
+
+static U32 HUF_decodeLastSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog)
+{
+ size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
+ memcpy(op, dt + val, 1);
+ if (dt[val].length == 1)
+ BIT_skipBits(DStream, dt[val].nbBits);
+ else {
+ if (DStream->bitsConsumed < (sizeof(DStream->bitContainer) * 8)) {
+ BIT_skipBits(DStream, dt[val].nbBits);
+ if (DStream->bitsConsumed > (sizeof(DStream->bitContainer) * 8))
+ /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
+ DStream->bitsConsumed = (sizeof(DStream->bitContainer) * 8);
+ }
+ }
+ return 1;
+}
+
+#define HUF_DECODE_SYMBOLX4_0(ptr, DStreamPtr) ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \
+ if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \
+ ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
+
+#define HUF_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \
+ if (ZSTD_64bits()) \
+ ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
+
+FORCE_INLINE size_t HUF_decodeStreamX4(BYTE *p, BIT_DStream_t *bitDPtr, BYTE *const pEnd, const HUF_DEltX4 *const dt, const U32 dtLog)
+{
+ BYTE *const pStart = p;
+
+ /* up to 8 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd - (sizeof(bitDPtr->bitContainer) - 1))) {
+ HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX4_1(p, bitDPtr);
+ HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
+ }
+
+ /* closer to end : up to 2 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd - 2))
+ HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
+
+ while (p <= pEnd - 2)
+ HUF_DECODE_SYMBOLX4_0(p, bitDPtr); /* no need to reload : reached the end of DStream */
+
+ if (p < pEnd)
+ p += HUF_decodeLastSymbolX4(p, bitDPtr, dt, dtLog);
+
+ return p - pStart;
+}
+
+static size_t HUF_decompress1X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ BIT_DStream_t bitD;
+
+ /* Init */
+ {
+ size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+
+ /* decode */
+ {
+ BYTE *const ostart = (BYTE *)dst;
+ BYTE *const oend = ostart + dstSize;
+ const void *const dtPtr = DTable + 1; /* force compiler to not use strict-aliasing */
+ const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ HUF_decodeStreamX4(ostart, &bitD, oend, dt, dtd.tableLog);
+ }
+
+ /* check */
+ if (!BIT_endOfDStream(&bitD))
+ return ERROR(corruption_detected);
+
+ /* decoded size */
+ return dstSize;
+}
+
+size_t HUF_decompress1X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 1)
+ return ERROR(GENERIC);
+ return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ const BYTE *ip = (const BYTE *)cSrc;
+
+ size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize);
+ if (HUF_isError(hSize))
+ return hSize;
+ if (hSize >= cSrcSize)
+ return ERROR(srcSize_wrong);
+ ip += hSize;
+ cSrcSize -= hSize;
+
+ return HUF_decompress1X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx);
+}
+
+static size_t HUF_decompress4X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ if (cSrcSize < 10)
+ return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
+
+ {
+ const BYTE *const istart = (const BYTE *)cSrc;
+ BYTE *const ostart = (BYTE *)dst;
+ BYTE *const oend = ostart + dstSize;
+ const void *const dtPtr = DTable + 1;
+ const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr;
+
+ /* Init */
+ BIT_DStream_t bitD1;
+ BIT_DStream_t bitD2;
+ BIT_DStream_t bitD3;
+ BIT_DStream_t bitD4;
+ size_t const length1 = ZSTD_readLE16(istart);
+ size_t const length2 = ZSTD_readLE16(istart + 2);
+ size_t const length3 = ZSTD_readLE16(istart + 4);
+ size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6);
+ const BYTE *const istart1 = istart + 6; /* jumpTable */
+ const BYTE *const istart2 = istart1 + length1;
+ const BYTE *const istart3 = istart2 + length2;
+ const BYTE *const istart4 = istart3 + length3;
+ size_t const segmentSize = (dstSize + 3) / 4;
+ BYTE *const opStart2 = ostart + segmentSize;
+ BYTE *const opStart3 = opStart2 + segmentSize;
+ BYTE *const opStart4 = opStart3 + segmentSize;
+ BYTE *op1 = ostart;
+ BYTE *op2 = opStart2;
+ BYTE *op3 = opStart3;
+ BYTE *op4 = opStart4;
+ U32 endSignal;
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ U32 const dtLog = dtd.tableLog;
+
+ if (length4 > cSrcSize)
+ return ERROR(corruption_detected); /* overflow */
+ {
+ size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+ {
+ size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4);
+ if (HUF_isError(errorCode))
+ return errorCode;
+ }
+
+ /* 16-32 symbols per loop (4-8 symbols per stream) */
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ for (; (endSignal == BIT_DStream_unfinished) & (op4 < (oend - (sizeof(bitD4.bitContainer) - 1)));) {
+ HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX4_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX4_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX4_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX4_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX4_0(op4, &bitD4);
+
+ endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
+ }
+
+ /* check corruption */
+ if (op1 > opStart2)
+ return ERROR(corruption_detected);
+ if (op2 > opStart3)
+ return ERROR(corruption_detected);
+ if (op3 > opStart4)
+ return ERROR(corruption_detected);
+ /* note : op4 already verified within main loop */
+
+ /* finish bitStreams one by one */
+ HUF_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog);
+ HUF_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog);
+ HUF_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog);
+ HUF_decodeStreamX4(op4, &bitD4, oend, dt, dtLog);
+
+ /* check */
+ {
+ U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
+ if (!endCheck)
+ return ERROR(corruption_detected);
+ }
+
+ /* decoded size */
+ return dstSize;
+ }
+}
+
+size_t HUF_decompress4X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ if (dtd.tableType != 1)
+ return ERROR(GENERIC);
+ return HUF_decompress4X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ const BYTE *ip = (const BYTE *)cSrc;
+
+ size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize);
+ if (HUF_isError(hSize))
+ return hSize;
+ if (hSize >= cSrcSize)
+ return ERROR(srcSize_wrong);
+ ip += hSize;
+ cSrcSize -= hSize;
+
+ return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx);
+}
+
+/* ********************************/
+/* Generic decompression selector */
+/* ********************************/
+
+size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ return dtd.tableType ? HUF_decompress1X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable)
+ : HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable);
+}
+
+size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable)
+{
+ DTableDesc const dtd = HUF_getDTableDesc(DTable);
+ return dtd.tableType ? HUF_decompress4X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable)
+ : HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable);
+}
+
+typedef struct {
+ U32 tableTime;
+ U32 decode256Time;
+} algo_time_t;
+static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] = {
+ /* single, double, quad */
+ {{0, 0}, {1, 1}, {2, 2}}, /* Q==0 : impossible */
+ {{0, 0}, {1, 1}, {2, 2}}, /* Q==1 : impossible */
+ {{38, 130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */
+ {{448, 128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */
+ {{556, 128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */
+ {{714, 128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */
+ {{883, 128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */
+ {{897, 128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */
+ {{926, 128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */
+ {{947, 128}, {1729, 77}, {3359, 77}}, /* Q == 9 : 56-62% */
+ {{1107, 128}, {2083, 81}, {4006, 84}}, /* Q ==10 : 62-69% */
+ {{1177, 128}, {2379, 87}, {4785, 88}}, /* Q ==11 : 69-75% */
+ {{1242, 128}, {2415, 93}, {5155, 84}}, /* Q ==12 : 75-81% */
+ {{1349, 128}, {2644, 106}, {5260, 106}}, /* Q ==13 : 81-87% */
+ {{1455, 128}, {2422, 124}, {4174, 124}}, /* Q ==14 : 87-93% */
+ {{722, 128}, {1891, 145}, {1936, 146}}, /* Q ==15 : 93-99% */
+};
+
+/** HUF_selectDecoder() :
+* Tells which decoder is likely to decode faster,
+* based on a set of pre-determined metrics.
+* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 .
+* Assumption : 0 < cSrcSize < dstSize <= 128 KB */
+U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize)
+{
+ /* decoder timing evaluation */
+ U32 const Q = (U32)(cSrcSize * 16 / dstSize); /* Q < 16 since dstSize > cSrcSize */
+ U32 const D256 = (U32)(dstSize >> 8);
+ U32 const DTime0 = algoTime[Q][0].tableTime + (algoTime[Q][0].decode256Time * D256);
+ U32 DTime1 = algoTime[Q][1].tableTime + (algoTime[Q][1].decode256Time * D256);
+ DTime1 += DTime1 >> 3; /* advantage to algorithm using less memory, for cache eviction */
+
+ return DTime1 < DTime0;
+}
+
+typedef size_t (*decompressionAlgo)(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize);
+
+size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ /* validation checks */
+ if (dstSize == 0)
+ return ERROR(dstSize_tooSmall);
+ if (cSrcSize > dstSize)
+ return ERROR(corruption_detected); /* invalid */
+ if (cSrcSize == dstSize) {
+ memcpy(dst, cSrc, dstSize);
+ return dstSize;
+ } /* not compressed */
+ if (cSrcSize == 1) {
+ memset(dst, *(const BYTE *)cSrc, dstSize);
+ return dstSize;
+ } /* RLE */
+
+ {
+ U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
+ return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize)
+ : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize);
+ }
+}
+
+size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ /* validation checks */
+ if (dstSize == 0)
+ return ERROR(dstSize_tooSmall);
+ if ((cSrcSize >= dstSize) || (cSrcSize <= 1))
+ return ERROR(corruption_detected); /* invalid */
+
+ {
+ U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
+ return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize)
+ : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize);
+ }
+}
+
+size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize)
+{
+ /* validation checks */
+ if (dstSize == 0)
+ return ERROR(dstSize_tooSmall);
+ if (cSrcSize > dstSize)
+ return ERROR(corruption_detected); /* invalid */
+ if (cSrcSize == dstSize) {
+ memcpy(dst, cSrc, dstSize);
+ return dstSize;
+ } /* not compressed */
+ if (cSrcSize == 1) {
+ memset(dst, *(const BYTE *)cSrc, dstSize);
+ return dstSize;
+ } /* RLE */
+
+ {
+ U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize);
+ return algoNb ? HUF_decompress1X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize)
+ : HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize);
+ }
+}
diff --git a/lib/zstd/mem.h b/lib/zstd/mem.h
new file mode 100644
index 0000000000..3a0f34c870
--- /dev/null
+++ b/lib/zstd/mem.h
@@ -0,0 +1,151 @@
+/**
+ * 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").
+ */
+
+#ifndef MEM_H_MODULE
+#define MEM_H_MODULE
+
+/*-****************************************
+* Dependencies
+******************************************/
+#include <asm/unaligned.h>
+#include <linux/string.h> /* memcpy */
+#include <linux/types.h> /* size_t, ptrdiff_t */
+
+/*-****************************************
+* Compiler specifics
+******************************************/
+#define ZSTD_STATIC static __inline __attribute__((unused))
+
+/*-**************************************************************
+* Basic Types
+*****************************************************************/
+typedef uint8_t BYTE;
+typedef uint16_t U16;
+typedef int16_t S16;
+typedef uint32_t U32;
+typedef int32_t S32;
+typedef uint64_t U64;
+typedef int64_t S64;
+typedef ptrdiff_t iPtrDiff;
+typedef uintptr_t uPtrDiff;
+
+/*-**************************************************************
+* Memory I/O
+*****************************************************************/
+ZSTD_STATIC unsigned ZSTD_32bits(void) { return sizeof(size_t) == 4; }
+ZSTD_STATIC unsigned ZSTD_64bits(void) { return sizeof(size_t) == 8; }
+
+#if defined(__LITTLE_ENDIAN)
+#define ZSTD_LITTLE_ENDIAN 1
+#else
+#define ZSTD_LITTLE_ENDIAN 0
+#endif
+
+ZSTD_STATIC unsigned ZSTD_isLittleEndian(void) { return ZSTD_LITTLE_ENDIAN; }
+
+ZSTD_STATIC U16 ZSTD_read16(const void *memPtr) { return get_unaligned((const U16 *)memPtr); }
+
+ZSTD_STATIC U32 ZSTD_read32(const void *memPtr) { return get_unaligned((const U32 *)memPtr); }
+
+ZSTD_STATIC U64 ZSTD_read64(const void *memPtr) { return get_unaligned((const U64 *)memPtr); }
+
+ZSTD_STATIC size_t ZSTD_readST(const void *memPtr) { return get_unaligned((const size_t *)memPtr); }
+
+ZSTD_STATIC void ZSTD_write16(void *memPtr, U16 value) { put_unaligned(value, (U16 *)memPtr); }
+
+ZSTD_STATIC void ZSTD_write32(void *memPtr, U32 value) { put_unaligned(value, (U32 *)memPtr); }
+
+ZSTD_STATIC void ZSTD_write64(void *memPtr, U64 value) { put_unaligned(value, (U64 *)memPtr); }
+
+/*=== Little endian r/w ===*/
+
+ZSTD_STATIC U16 ZSTD_readLE16(const void *memPtr) { return get_unaligned_le16(memPtr); }
+
+ZSTD_STATIC void ZSTD_writeLE16(void *memPtr, U16 val) { put_unaligned_le16(val, memPtr); }
+
+ZSTD_STATIC U32 ZSTD_readLE24(const void *memPtr) { return ZSTD_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16); }
+
+ZSTD_STATIC void ZSTD_writeLE24(void *memPtr, U32 val)
+{
+ ZSTD_writeLE16(memPtr, (U16)val);
+ ((BYTE *)memPtr)[2] = (BYTE)(val >> 16);
+}
+
+ZSTD_STATIC U32 ZSTD_readLE32(const void *memPtr) { return get_unaligned_le32(memPtr); }
+
+ZSTD_STATIC void ZSTD_writeLE32(void *memPtr, U32 val32) { put_unaligned_le32(val32, memPtr); }
+
+ZSTD_STATIC U64 ZSTD_readLE64(const void *memPtr) { return get_unaligned_le64(memPtr); }
+
+ZSTD_STATIC void ZSTD_writeLE64(void *memPtr, U64 val64) { put_unaligned_le64(val64, memPtr); }
+
+ZSTD_STATIC size_t ZSTD_readLEST(const void *memPtr)
+{
+ if (ZSTD_32bits())
+ return (size_t)ZSTD_readLE32(memPtr);
+ else
+ return (size_t)ZSTD_readLE64(memPtr);
+}
+
+ZSTD_STATIC void ZSTD_writeLEST(void *memPtr, size_t val)
+{
+ if (ZSTD_32bits())
+ ZSTD_writeLE32(memPtr, (U32)val);
+ else
+ ZSTD_writeLE64(memPtr, (U64)val);
+}
+
+/*=== Big endian r/w ===*/
+
+ZSTD_STATIC U32 ZSTD_readBE32(const void *memPtr) { return get_unaligned_be32(memPtr); }
+
+ZSTD_STATIC void ZSTD_writeBE32(void *memPtr, U32 val32) { put_unaligned_be32(val32, memPtr); }
+
+ZSTD_STATIC U64 ZSTD_readBE64(const void *memPtr) { return get_unaligned_be64(memPtr); }
+
+ZSTD_STATIC void ZSTD_writeBE64(void *memPtr, U64 val64) { put_unaligned_be64(val64, memPtr); }
+
+ZSTD_STATIC size_t ZSTD_readBEST(const void *memPtr)
+{
+ if (ZSTD_32bits())
+ return (size_t)ZSTD_readBE32(memPtr);
+ else
+ return (size_t)ZSTD_readBE64(memPtr);
+}
+
+ZSTD_STATIC void ZSTD_writeBEST(void *memPtr, size_t val)
+{
+ if (ZSTD_32bits())
+ ZSTD_writeBE32(memPtr, (U32)val);
+ else
+ ZSTD_writeBE64(memPtr, (U64)val);
+}
+
+/* function safe only for comparisons */
+ZSTD_STATIC U32 ZSTD_readMINMATCH(const void *memPtr, U32 length)
+{
+ switch (length) {
+ default:
+ case 4: return ZSTD_read32(memPtr);
+ case 3:
+ if (ZSTD_isLittleEndian())
+ return ZSTD_read32(memPtr) << 8;
+ else
+ return ZSTD_read32(memPtr) >> 8;
+ }
+}
+
+#endif /* MEM_H_MODULE */
diff --git a/lib/zstd/zstd_common.c b/lib/zstd/zstd_common.c
new file mode 100644
index 0000000000..a282624ee1
--- /dev/null
+++ b/lib/zstd/zstd_common.c
@@ -0,0 +1,75 @@
+/**
+ * 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").
+ */
+
+/*-*************************************
+* Dependencies
+***************************************/
+#include "error_private.h"
+#include "zstd_internal.h" /* declaration of ZSTD_isError, ZSTD_getErrorName, ZSTD_getErrorCode, ZSTD_getErrorString, ZSTD_versionNumber */
+#include <linux/kernel.h>
+
+/*=**************************************************************
+* Custom allocator
+****************************************************************/
+
+#define stack_push(stack, size) \
+ ({ \
+ void *const ptr = ZSTD_PTR_ALIGN((stack)->ptr); \
+ (stack)->ptr = (char *)ptr + (size); \
+ (stack)->ptr <= (stack)->end ? ptr : NULL; \
+ })
+
+ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize)
+{
+ ZSTD_customMem stackMem = {ZSTD_stackAlloc, ZSTD_stackFree, workspace};
+ ZSTD_stack *stack = (ZSTD_stack *)workspace;
+ /* Verify preconditions */
+ if (!workspace || workspaceSize < sizeof(ZSTD_stack) || workspace != ZSTD_PTR_ALIGN(workspace)) {
+ ZSTD_customMem error = {NULL, NULL, NULL};
+ return error;
+ }
+ /* Initialize the stack */
+ stack->ptr = workspace;
+ stack->end = (char *)workspace + workspaceSize;
+ stack_push(stack, sizeof(ZSTD_stack));
+ return stackMem;
+}
+
+void *ZSTD_stackAllocAll(void *opaque, size_t *size)
+{
+ ZSTD_stack *stack = (ZSTD_stack *)opaque;
+ *size = (BYTE const *)stack->end - (BYTE *)ZSTD_PTR_ALIGN(stack->ptr);
+ return stack_push(stack, *size);
+}
+
+void *ZSTD_stackAlloc(void *opaque, size_t size)
+{
+ ZSTD_stack *stack = (ZSTD_stack *)opaque;
+ return stack_push(stack, size);
+}
+void ZSTD_stackFree(void *opaque, void *address)
+{
+ (void)opaque;
+ (void)address;
+}
+
+void *ZSTD_malloc(size_t size, ZSTD_customMem customMem) { return customMem.customAlloc(customMem.opaque, size); }
+
+void ZSTD_free(void *ptr, ZSTD_customMem customMem)
+{
+ if (ptr != NULL)
+ customMem.customFree(customMem.opaque, ptr);
+}
diff --git a/lib/zstd/zstd_internal.h b/lib/zstd/zstd_internal.h
new file mode 100644
index 0000000000..1a79fab9e1
--- /dev/null
+++ b/lib/zstd/zstd_internal.h
@@ -0,0 +1,263 @@
+/**
+ * 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").
+ */
+
+#ifndef ZSTD_CCOMMON_H_MODULE
+#define ZSTD_CCOMMON_H_MODULE
+
+/*-*******************************************************
+* Compiler specifics
+*********************************************************/
+#define FORCE_INLINE static __always_inline
+#define FORCE_NOINLINE static noinline
+
+/*-*************************************
+* Dependencies
+***************************************/
+#include "error_private.h"
+#include "mem.h"
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/xxhash.h>
+#include <linux/zstd.h>
+
+/*-*************************************
+* shared macros
+***************************************/
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define CHECK_F(f) \
+ { \
+ size_t const errcod = f; \
+ if (ERR_isError(errcod)) \
+ return errcod; \
+ } /* check and Forward error code */
+#define CHECK_E(f, e) \
+ { \
+ size_t const errcod = f; \
+ if (ERR_isError(errcod)) \
+ return ERROR(e); \
+ } /* check and send Error code */
+#define ZSTD_STATIC_ASSERT(c) \
+ { \
+ enum { ZSTD_static_assert = 1 / (int)(!!(c)) }; \
+ }
+
+/*-*************************************
+* Common constants
+***************************************/
+#define ZSTD_OPT_NUM (1 << 12)
+#define ZSTD_DICT_MAGIC 0xEC30A437 /* v0.7+ */
+
+#define ZSTD_REP_NUM 3 /* number of repcodes */
+#define ZSTD_REP_CHECK (ZSTD_REP_NUM) /* number of repcodes to check by the optimal parser */
+#define ZSTD_REP_MOVE (ZSTD_REP_NUM - 1)
+#define ZSTD_REP_MOVE_OPT (ZSTD_REP_NUM)
+static const U32 repStartValue[ZSTD_REP_NUM] = {1, 4, 8};
+
+#define KB *(1 << 10)
+#define MB *(1 << 20)
+#define GB *(1U << 30)
+
+#define BIT7 128
+#define BIT6 64
+#define BIT5 32
+#define BIT4 16
+#define BIT1 2
+#define BIT0 1
+
+#define ZSTD_WINDOWLOG_ABSOLUTEMIN 10
+static const size_t ZSTD_fcs_fieldSize[4] = {0, 2, 4, 8};
+static const size_t ZSTD_did_fieldSize[4] = {0, 1, 2, 4};
+
+#define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */
+static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE;
+typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
+
+#define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
+#define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */) /* for a non-null block */
+
+#define HufLog 12
+typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e;
+
+#define LONGNBSEQ 0x7F00
+
+#define MINMATCH 3
+#define EQUAL_READ32 4
+
+#define Litbits 8
+#define MaxLit ((1 << Litbits) - 1)
+#define MaxML 52
+#define MaxLL 35
+#define MaxOff 28
+#define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */
+#define MLFSELog 9
+#define LLFSELog 9
+#define OffFSELog 8
+
+static const U32 LL_bits[MaxLL + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
+static const S16 LL_defaultNorm[MaxLL + 1] = {4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1, -1, -1, -1, -1};
+#define LL_DEFAULTNORMLOG 6 /* for static allocation */
+static const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG;
+
+static const U32 ML_bits[MaxML + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
+static const S16 ML_defaultNorm[MaxML + 1] = {1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1};
+#define ML_DEFAULTNORMLOG 6 /* for static allocation */
+static const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG;
+
+static const S16 OF_defaultNorm[MaxOff + 1] = {1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1};
+#define OF_DEFAULTNORMLOG 5 /* for static allocation */
+static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
+
+/*-*******************************************
+* Shared functions to include for inlining
+*********************************************/
+ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) {
+ memcpy(dst, src, 8);
+}
+/*! ZSTD_wildcopy() :
+* custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */
+#define WILDCOPY_OVERLENGTH 8
+ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
+{
+ const BYTE* ip = (const BYTE*)src;
+ BYTE* op = (BYTE*)dst;
+ BYTE* const oend = op + length;
+ /* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388.
+ * Avoid the bad case where the loop only runs once by handling the
+ * special case separately. This doesn't trigger the bug because it
+ * doesn't involve pointer/integer overflow.
+ */
+ if (length <= 8)
+ return ZSTD_copy8(dst, src);
+ do {
+ ZSTD_copy8(op, ip);
+ op += 8;
+ ip += 8;
+ } while (op < oend);
+}
+
+/*-*******************************************
+* Private interfaces
+*********************************************/
+typedef struct ZSTD_stats_s ZSTD_stats_t;
+
+typedef struct {
+ U32 off;
+ U32 len;
+} ZSTD_match_t;
+
+typedef struct {
+ U32 price;
+ U32 off;
+ U32 mlen;
+ U32 litlen;
+ U32 rep[ZSTD_REP_NUM];
+} ZSTD_optimal_t;
+
+typedef struct seqDef_s {
+ U32 offset;
+ U16 litLength;
+ U16 matchLength;
+} seqDef;
+
+typedef struct {
+ seqDef *sequencesStart;
+ seqDef *sequences;
+ BYTE *litStart;
+ BYTE *lit;
+ BYTE *llCode;
+ BYTE *mlCode;
+ BYTE *ofCode;
+ U32 longLengthID; /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
+ U32 longLengthPos;
+ /* opt */
+ ZSTD_optimal_t *priceTable;
+ ZSTD_match_t *matchTable;
+ U32 *matchLengthFreq;
+ U32 *litLengthFreq;
+ U32 *litFreq;
+ U32 *offCodeFreq;
+ U32 matchLengthSum;
+ U32 matchSum;
+ U32 litLengthSum;
+ U32 litSum;
+ U32 offCodeSum;
+ U32 log2matchLengthSum;
+ U32 log2matchSum;
+ U32 log2litLengthSum;
+ U32 log2litSum;
+ U32 log2offCodeSum;
+ U32 factor;
+ U32 staticPrices;
+ U32 cachedPrice;
+ U32 cachedLitLength;
+ const BYTE *cachedLiterals;
+} seqStore_t;
+
+const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx);
+void ZSTD_seqToCodes(const seqStore_t *seqStorePtr);
+int ZSTD_isSkipFrame(ZSTD_DCtx *dctx);
+
+/*= Custom memory allocation functions */
+typedef void *(*ZSTD_allocFunction)(void *opaque, size_t size);
+typedef void (*ZSTD_freeFunction)(void *opaque, void *address);
+typedef struct {
+ ZSTD_allocFunction customAlloc;
+ ZSTD_freeFunction customFree;
+ void *opaque;
+} ZSTD_customMem;
+
+void *ZSTD_malloc(size_t size, ZSTD_customMem customMem);
+void ZSTD_free(void *ptr, ZSTD_customMem customMem);
+
+/*====== stack allocation ======*/
+
+typedef struct {
+ void *ptr;
+ const void *end;
+} ZSTD_stack;
+
+#define ZSTD_ALIGN(x) ALIGN(x, sizeof(size_t))
+#define ZSTD_PTR_ALIGN(p) PTR_ALIGN(p, sizeof(size_t))
+
+ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize);
+
+void *ZSTD_stackAllocAll(void *opaque, size_t *size);
+void *ZSTD_stackAlloc(void *opaque, size_t size);
+void ZSTD_stackFree(void *opaque, void *address);
+
+/*====== common function ======*/
+
+ZSTD_STATIC U32 ZSTD_highbit32(U32 val) { return 31 - __builtin_clz(val); }
+
+/* hidden functions */
+
+/* ZSTD_invalidateRepCodes() :
+ * ensures next compression will not use repcodes from previous block.
+ * Note : only works with regular variant;
+ * do not use with extDict variant ! */
+void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx);
+
+size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx);
+size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx);
+size_t ZSTD_freeCDict(ZSTD_CDict *cdict);
+size_t ZSTD_freeDDict(ZSTD_DDict *cdict);
+size_t ZSTD_freeCStream(ZSTD_CStream *zcs);
+size_t ZSTD_freeDStream(ZSTD_DStream *zds);
+
+#endif /* ZSTD_CCOMMON_H_MODULE */
diff --git a/lib/zstd/zstd_opt.h b/lib/zstd/zstd_opt.h
new file mode 100644
index 0000000000..55e1b4cba8
--- /dev/null
+++ b/lib/zstd/zstd_opt.h
@@ -0,0 +1,1014 @@
+/**
+ * Copyright (c) 2016-present, Przemyslaw Skibinski, 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").
+ */
+
+/* Note : this file is intended to be included within zstd_compress.c */
+
+#ifndef ZSTD_OPT_H_91842398743
+#define ZSTD_OPT_H_91842398743
+
+#define ZSTD_LITFREQ_ADD 2
+#define ZSTD_FREQ_DIV 4
+#define ZSTD_MAX_PRICE (1 << 30)
+
+/*-*************************************
+* Price functions for optimal parser
+***************************************/
+FORCE_INLINE void ZSTD_setLog2Prices(seqStore_t *ssPtr)
+{
+ ssPtr->log2matchLengthSum = ZSTD_highbit32(ssPtr->matchLengthSum + 1);
+ ssPtr->log2litLengthSum = ZSTD_highbit32(ssPtr->litLengthSum + 1);
+ ssPtr->log2litSum = ZSTD_highbit32(ssPtr->litSum + 1);
+ ssPtr->log2offCodeSum = ZSTD_highbit32(ssPtr->offCodeSum + 1);
+ ssPtr->factor = 1 + ((ssPtr->litSum >> 5) / ssPtr->litLengthSum) + ((ssPtr->litSum << 1) / (ssPtr->litSum + ssPtr->matchSum));
+}
+
+ZSTD_STATIC void ZSTD_rescaleFreqs(seqStore_t *ssPtr, const BYTE *src, size_t srcSize)
+{
+ unsigned u;
+
+ ssPtr->cachedLiterals = NULL;
+ ssPtr->cachedPrice = ssPtr->cachedLitLength = 0;
+ ssPtr->staticPrices = 0;
+
+ if (ssPtr->litLengthSum == 0) {
+ if (srcSize <= 1024)
+ ssPtr->staticPrices = 1;
+
+ for (u = 0; u <= MaxLit; u++)
+ ssPtr->litFreq[u] = 0;
+ for (u = 0; u < srcSize; u++)
+ ssPtr->litFreq[src[u]]++;
+
+ ssPtr->litSum = 0;
+ ssPtr->litLengthSum = MaxLL + 1;
+ ssPtr->matchLengthSum = MaxML + 1;
+ ssPtr->offCodeSum = (MaxOff + 1);
+ ssPtr->matchSum = (ZSTD_LITFREQ_ADD << Litbits);
+
+ for (u = 0; u <= MaxLit; u++) {
+ ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> ZSTD_FREQ_DIV);
+ ssPtr->litSum += ssPtr->litFreq[u];
+ }
+ for (u = 0; u <= MaxLL; u++)
+ ssPtr->litLengthFreq[u] = 1;
+ for (u = 0; u <= MaxML; u++)
+ ssPtr->matchLengthFreq[u] = 1;
+ for (u = 0; u <= MaxOff; u++)
+ ssPtr->offCodeFreq[u] = 1;
+ } else {
+ ssPtr->matchLengthSum = 0;
+ ssPtr->litLengthSum = 0;
+ ssPtr->offCodeSum = 0;
+ ssPtr->matchSum = 0;
+ ssPtr->litSum = 0;
+
+ for (u = 0; u <= MaxLit; u++) {
+ ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> (ZSTD_FREQ_DIV + 1));
+ ssPtr->litSum += ssPtr->litFreq[u];
+ }
+ for (u = 0; u <= MaxLL; u++) {
+ ssPtr->litLengthFreq[u] = 1 + (ssPtr->litLengthFreq[u] >> (ZSTD_FREQ_DIV + 1));
+ ssPtr->litLengthSum += ssPtr->litLengthFreq[u];
+ }
+ for (u = 0; u <= MaxML; u++) {
+ ssPtr->matchLengthFreq[u] = 1 + (ssPtr->matchLengthFreq[u] >> ZSTD_FREQ_DIV);
+ ssPtr->matchLengthSum += ssPtr->matchLengthFreq[u];
+ ssPtr->matchSum += ssPtr->matchLengthFreq[u] * (u + 3);
+ }
+ ssPtr->matchSum *= ZSTD_LITFREQ_ADD;
+ for (u = 0; u <= MaxOff; u++) {
+ ssPtr->offCodeFreq[u] = 1 + (ssPtr->offCodeFreq[u] >> ZSTD_FREQ_DIV);
+ ssPtr->offCodeSum += ssPtr->offCodeFreq[u];
+ }
+ }
+
+ ZSTD_setLog2Prices(ssPtr);
+}
+
+FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t *ssPtr, U32 litLength, const BYTE *literals)
+{
+ U32 price, u;
+
+ if (ssPtr->staticPrices)
+ return ZSTD_highbit32((U32)litLength + 1) + (litLength * 6);
+
+ if (litLength == 0)
+ return ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[0] + 1);
+
+ /* literals */
+ if (ssPtr->cachedLiterals == literals) {
+ U32 const additional = litLength - ssPtr->cachedLitLength;
+ const BYTE *literals2 = ssPtr->cachedLiterals + ssPtr->cachedLitLength;
+ price = ssPtr->cachedPrice + additional * ssPtr->log2litSum;
+ for (u = 0; u < additional; u++)
+ price -= ZSTD_highbit32(ssPtr->litFreq[literals2[u]] + 1);
+ ssPtr->cachedPrice = price;
+ ssPtr->cachedLitLength = litLength;
+ } else {
+ price = litLength * ssPtr->log2litSum;
+ for (u = 0; u < litLength; u++)
+ price -= ZSTD_highbit32(ssPtr->litFreq[literals[u]] + 1);
+
+ if (litLength >= 12) {
+ ssPtr->cachedLiterals = literals;
+ ssPtr->cachedPrice = price;
+ ssPtr->cachedLitLength = litLength;
+ }
+ }
+
+ /* literal Length */
+ {
+ const BYTE LL_deltaCode = 19;
+ const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
+ price += LL_bits[llCode] + ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[llCode] + 1);
+ }
+
+ return price;
+}
+
+FORCE_INLINE U32 ZSTD_getPrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength, const int ultra)
+{
+ /* offset */
+ U32 price;
+ BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1);
+
+ if (seqStorePtr->staticPrices)
+ return ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit32((U32)matchLength + 1) + 16 + offCode;
+
+ price = offCode + seqStorePtr->log2offCodeSum - ZSTD_highbit32(seqStorePtr->offCodeFreq[offCode] + 1);
+ if (!ultra && offCode >= 20)
+ price += (offCode - 19) * 2;
+
+ /* match Length */
+ {
+ const BYTE ML_deltaCode = 36;
+ const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
+ price += ML_bits[mlCode] + seqStorePtr->log2matchLengthSum - ZSTD_highbit32(seqStorePtr->matchLengthFreq[mlCode] + 1);
+ }
+
+ return price + ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + seqStorePtr->factor;
+}
+
+ZSTD_STATIC void ZSTD_updatePrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength)
+{
+ U32 u;
+
+ /* literals */
+ seqStorePtr->litSum += litLength * ZSTD_LITFREQ_ADD;
+ for (u = 0; u < litLength; u++)
+ seqStorePtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD;
+
+ /* literal Length */
+ {
+ const BYTE LL_deltaCode = 19;
+ const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength];
+ seqStorePtr->litLengthFreq[llCode]++;
+ seqStorePtr->litLengthSum++;
+ }
+
+ /* match offset */
+ {
+ BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1);
+ seqStorePtr->offCodeSum++;
+ seqStorePtr->offCodeFreq[offCode]++;
+ }
+
+ /* match Length */
+ {
+ const BYTE ML_deltaCode = 36;
+ const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength];
+ seqStorePtr->matchLengthFreq[mlCode]++;
+ seqStorePtr->matchLengthSum++;
+ }
+
+ ZSTD_setLog2Prices(seqStorePtr);
+}
+
+#define SET_PRICE(pos, mlen_, offset_, litlen_, price_) \
+ { \
+ while (last_pos < pos) { \
+ opt[last_pos + 1].price = ZSTD_MAX_PRICE; \
+ last_pos++; \
+ } \
+ opt[pos].mlen = mlen_; \
+ opt[pos].off = offset_; \
+ opt[pos].litlen = litlen_; \
+ opt[pos].price = price_; \
+ }
+
+/* Update hashTable3 up to ip (excluded)
+ Assumption : always within prefix (i.e. not within extDict) */
+FORCE_INLINE
+U32 ZSTD_insertAndFindFirstIndexHash3(ZSTD_CCtx *zc, const BYTE *ip)
+{
+ U32 *const hashTable3 = zc->hashTable3;
+ U32 const hashLog3 = zc->hashLog3;
+ const BYTE *const base = zc->base;
+ U32 idx = zc->nextToUpdate3;
+ const U32 target = zc->nextToUpdate3 = (U32)(ip - base);
+ const size_t hash3 = ZSTD_hash3Ptr(ip, hashLog3);
+
+ while (idx < target) {
+ hashTable3[ZSTD_hash3Ptr(base + idx, hashLog3)] = idx;
+ idx++;
+ }
+
+ return hashTable3[hash3];
+}
+
+/*-*************************************
+* Binary Tree search
+***************************************/
+static U32 ZSTD_insertBtAndGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, U32 nbCompares, const U32 mls, U32 extDict,
+ ZSTD_match_t *matches, const U32 minMatchLen)
+{
+ const BYTE *const base = zc->base;
+ const U32 curr = (U32)(ip - base);
+ const U32 hashLog = zc->params.cParams.hashLog;
+ const size_t h = ZSTD_hashPtr(ip, hashLog, mls);
+ U32 *const hashTable = zc->hashTable;
+ U32 matchIndex = hashTable[h];
+ U32 *const bt = zc->chainTable;
+ const U32 btLog = zc->params.cParams.chainLog - 1;
+ const U32 btMask = (1U << btLog) - 1;
+ size_t commonLengthSmaller = 0, commonLengthLarger = 0;
+ const BYTE *const dictBase = zc->dictBase;
+ const U32 dictLimit = zc->dictLimit;
+ const BYTE *const dictEnd = dictBase + dictLimit;
+ const BYTE *const prefixStart = base + dictLimit;
+ const U32 btLow = btMask >= curr ? 0 : curr - btMask;
+ const U32 windowLow = zc->lowLimit;
+ U32 *smallerPtr = bt + 2 * (curr & btMask);
+ U32 *largerPtr = bt + 2 * (curr & btMask) + 1;
+ U32 matchEndIdx = curr + 8;
+ U32 dummy32; /* to be nullified at the end */
+ U32 mnum = 0;
+
+ const U32 minMatch = (mls == 3) ? 3 : 4;
+ size_t bestLength = minMatchLen - 1;
+
+ if (minMatch == 3) { /* HC3 match finder */
+ U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3(zc, ip);
+ if (matchIndex3 > windowLow && (curr - matchIndex3 < (1 << 18))) {
+ const BYTE *match;
+ size_t currMl = 0;
+ if ((!extDict) || matchIndex3 >= dictLimit) {
+ match = base + matchIndex3;
+ if (match[bestLength] == ip[bestLength])
+ currMl = ZSTD_count(ip, match, iLimit);
+ } else {
+ match = dictBase + matchIndex3;
+ if (ZSTD_readMINMATCH(match, MINMATCH) ==
+ ZSTD_readMINMATCH(ip, MINMATCH)) /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */
+ currMl = ZSTD_count_2segments(ip + MINMATCH, match + MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH;
+ }
+
+ /* save best solution */
+ if (currMl > bestLength) {
+ bestLength = currMl;
+ matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex3;
+ matches[mnum].len = (U32)currMl;
+ mnum++;
+ if (currMl > ZSTD_OPT_NUM)
+ goto update;
+ if (ip + currMl == iLimit)
+ goto update; /* best possible, and avoid read overflow*/
+ }
+ }
+ }
+
+ hashTable[h] = curr; /* Update Hash Table */
+
+ while (nbCompares-- && (matchIndex > windowLow)) {
+ U32 *nextPtr = bt + 2 * (matchIndex & btMask);
+ size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */
+ const BYTE *match;
+
+ if ((!extDict) || (matchIndex + matchLength >= dictLimit)) {
+ match = base + matchIndex;
+ if (match[matchLength] == ip[matchLength]) {
+ matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iLimit) + 1;
+ }
+ } else {
+ match = dictBase + matchIndex;
+ matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iLimit, dictEnd, prefixStart);
+ if (matchIndex + matchLength >= dictLimit)
+ match = base + matchIndex; /* to prepare for next usage of match[matchLength] */
+ }
+
+ if (matchLength > bestLength) {
+ if (matchLength > matchEndIdx - matchIndex)
+ matchEndIdx = matchIndex + (U32)matchLength;
+ bestLength = matchLength;
+ matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex;
+ matches[mnum].len = (U32)matchLength;
+ mnum++;
+ if (matchLength > ZSTD_OPT_NUM)
+ break;
+ if (ip + matchLength == iLimit) /* equal : no way to know if inf or sup */
+ break; /* drop, to guarantee consistency (miss a little bit of compression) */
+ }
+
+ if (match[matchLength] < ip[matchLength]) {
+ /* match is smaller than curr */
+ *smallerPtr = matchIndex; /* update smaller idx */
+ commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */
+ if (matchIndex <= btLow) {
+ smallerPtr = &dummy32;
+ break;
+ } /* beyond tree size, stop the search */
+ smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */
+ matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */
+ } else {
+ /* match is larger than curr */
+ *largerPtr = matchIndex;
+ commonLengthLarger = matchLength;
+ if (matchIndex <= btLow) {
+ largerPtr = &dummy32;
+ break;
+ } /* beyond tree size, stop the search */
+ largerPtr = nextPtr;
+ matchIndex = nextPtr[0];
+ }
+ }
+
+ *smallerPtr = *largerPtr = 0;
+
+update:
+ zc->nextToUpdate = (matchEndIdx > curr + 8) ? matchEndIdx - 8 : curr + 1;
+ return mnum;
+}
+
+/** Tree updater, providing best match */
+static U32 ZSTD_BtGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls, ZSTD_match_t *matches,
+ const U32 minMatchLen)
+{
+ if (ip < zc->base + zc->nextToUpdate)
+ return 0; /* skipped area */
+ ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls);
+ return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 0, matches, minMatchLen);
+}
+
+static U32 ZSTD_BtGetAllMatches_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */
+ const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch,
+ ZSTD_match_t *matches, const U32 minMatchLen)
+{
+ switch (matchLengthSearch) {
+ case 3: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
+ default:
+ case 4: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
+ case 5: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
+ case 7:
+ case 6: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
+ }
+}
+
+/** Tree updater, providing best match */
+static U32 ZSTD_BtGetAllMatches_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls,
+ ZSTD_match_t *matches, const U32 minMatchLen)
+{
+ if (ip < zc->base + zc->nextToUpdate)
+ return 0; /* skipped area */
+ ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls);
+ return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 1, matches, minMatchLen);
+}
+
+static U32 ZSTD_BtGetAllMatches_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */
+ const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch,
+ ZSTD_match_t *matches, const U32 minMatchLen)
+{
+ switch (matchLengthSearch) {
+ case 3: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen);
+ default:
+ case 4: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen);
+ case 5: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen);
+ case 7:
+ case 6: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen);
+ }
+}
+
+/*-*******************************
+* Optimal parser
+*********************************/
+FORCE_INLINE
+void ZSTD_compressBlock_opt_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra)
+{
+ seqStore_t *seqStorePtr = &(ctx->seqStore);
+ const BYTE *const istart = (const BYTE *)src;
+ const BYTE *ip = istart;
+ const BYTE *anchor = istart;
+ const BYTE *const iend = istart + srcSize;
+ const BYTE *const ilimit = iend - 8;
+ const BYTE *const base = ctx->base;
+ const BYTE *const prefixStart = base + ctx->dictLimit;
+
+ const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
+ const U32 sufficient_len = ctx->params.cParams.targetLength;
+ const U32 mls = ctx->params.cParams.searchLength;
+ const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
+
+ ZSTD_optimal_t *opt = seqStorePtr->priceTable;
+ ZSTD_match_t *matches = seqStorePtr->matchTable;
+ const BYTE *inr;
+ U32 offset, rep[ZSTD_REP_NUM];
+
+ /* init */
+ ctx->nextToUpdate3 = ctx->nextToUpdate;
+ ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize);
+ ip += (ip == prefixStart);
+ {
+ U32 i;
+ for (i = 0; i < ZSTD_REP_NUM; i++)
+ rep[i] = ctx->rep[i];
+ }
+
+ /* Match Loop */
+ while (ip < ilimit) {
+ U32 cur, match_num, last_pos, litlen, price;
+ U32 u, mlen, best_mlen, best_off, litLength;
+ memset(opt, 0, sizeof(ZSTD_optimal_t));
+ last_pos = 0;
+ litlen = (U32)(ip - anchor);
+
+ /* check repCode */
+ {
+ U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor);
+ for (i = (ip == anchor); i < last_i; i++) {
+ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
+ if ((repCur > 0) && (repCur < (S32)(ip - prefixStart)) &&
+ (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repCur, minMatch))) {
+ mlen = (U32)ZSTD_count(ip + minMatch, ip + minMatch - repCur, iend) + minMatch;
+ if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
+ best_mlen = mlen;
+ best_off = i;
+ cur = 0;
+ last_pos = 1;
+ goto _storeSequence;
+ }
+ best_off = i - (ip == anchor);
+ do {
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
+ if (mlen > last_pos || price < opt[mlen].price)
+ SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
+ mlen--;
+ } while (mlen >= minMatch);
+ }
+ }
+ }
+
+ match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, ip, iend, maxSearches, mls, matches, minMatch);
+
+ if (!last_pos && !match_num) {
+ ip++;
+ continue;
+ }
+
+ if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
+ best_mlen = matches[match_num - 1].len;
+ best_off = matches[match_num - 1].off;
+ cur = 0;
+ last_pos = 1;
+ goto _storeSequence;
+ }
+
+ /* set prices using matches at position = 0 */
+ best_mlen = (last_pos) ? last_pos : minMatch;
+ for (u = 0; u < match_num; u++) {
+ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
+ best_mlen = matches[u].len;
+ while (mlen <= best_mlen) {
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
+ if (mlen > last_pos || price < opt[mlen].price)
+ SET_PRICE(mlen, mlen, matches[u].off, litlen, price); /* note : macro modifies last_pos */
+ mlen++;
+ }
+ }
+
+ if (last_pos < minMatch) {
+ ip++;
+ continue;
+ }
+
+ /* initialize opt[0] */
+ {
+ U32 i;
+ for (i = 0; i < ZSTD_REP_NUM; i++)
+ opt[0].rep[i] = rep[i];
+ }
+ opt[0].mlen = 1;
+ opt[0].litlen = litlen;
+
+ /* check further positions */
+ for (cur = 1; cur <= last_pos; cur++) {
+ inr = ip + cur;
+
+ if (opt[cur - 1].mlen == 1) {
+ litlen = opt[cur - 1].litlen + 1;
+ if (cur > litlen) {
+ price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen);
+ } else
+ price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
+ } else {
+ litlen = 1;
+ price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1);
+ }
+
+ if (cur > last_pos || price <= opt[cur].price)
+ SET_PRICE(cur, 1, 0, litlen, price);
+
+ if (cur == last_pos)
+ break;
+
+ if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */
+ continue;
+
+ mlen = opt[cur].mlen;
+ if (opt[cur].off > ZSTD_REP_MOVE_OPT) {
+ opt[cur].rep[2] = opt[cur - mlen].rep[1];
+ opt[cur].rep[1] = opt[cur - mlen].rep[0];
+ opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
+ } else {
+ opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2];
+ opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1];
+ opt[cur].rep[0] =
+ ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]);
+ }
+
+ best_mlen = minMatch;
+ {
+ U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
+ for (i = (opt[cur].mlen != 1); i < last_i; i++) { /* check rep */
+ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
+ if ((repCur > 0) && (repCur < (S32)(inr - prefixStart)) &&
+ (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(inr - repCur, minMatch))) {
+ mlen = (U32)ZSTD_count(inr + minMatch, inr + minMatch - repCur, iend) + minMatch;
+
+ if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
+ best_mlen = mlen;
+ best_off = i;
+ last_pos = cur + 1;
+ goto _storeSequence;
+ }
+
+ best_off = i - (opt[cur].mlen != 1);
+ if (mlen > best_mlen)
+ best_mlen = mlen;
+
+ do {
+ if (opt[cur].mlen == 1) {
+ litlen = opt[cur].litlen;
+ if (cur > litlen) {
+ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen,
+ best_off, mlen - MINMATCH, ultra);
+ } else
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
+ } else {
+ litlen = 0;
+ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
+ }
+
+ if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
+ SET_PRICE(cur + mlen, mlen, i, litlen, price);
+ mlen--;
+ } while (mlen >= minMatch);
+ }
+ }
+ }
+
+ match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, inr, iend, maxSearches, mls, matches, best_mlen);
+
+ if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
+ best_mlen = matches[match_num - 1].len;
+ best_off = matches[match_num - 1].off;
+ last_pos = cur + 1;
+ goto _storeSequence;
+ }
+
+ /* set prices using matches at position = cur */
+ for (u = 0; u < match_num; u++) {
+ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
+ best_mlen = matches[u].len;
+
+ while (mlen <= best_mlen) {
+ if (opt[cur].mlen == 1) {
+ litlen = opt[cur].litlen;
+ if (cur > litlen)
+ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen,
+ matches[u].off - 1, mlen - MINMATCH, ultra);
+ else
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
+ } else {
+ litlen = 0;
+ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra);
+ }
+
+ if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
+ SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
+
+ mlen++;
+ }
+ }
+ }
+
+ best_mlen = opt[last_pos].mlen;
+ best_off = opt[last_pos].off;
+ cur = last_pos - best_mlen;
+
+ /* store sequence */
+_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
+ opt[0].mlen = 1;
+
+ while (1) {
+ mlen = opt[cur].mlen;
+ offset = opt[cur].off;
+ opt[cur].mlen = best_mlen;
+ opt[cur].off = best_off;
+ best_mlen = mlen;
+ best_off = offset;
+ if (mlen > cur)
+ break;
+ cur -= mlen;
+ }
+
+ for (u = 0; u <= last_pos;) {
+ u += opt[u].mlen;
+ }
+
+ for (cur = 0; cur < last_pos;) {
+ mlen = opt[cur].mlen;
+ if (mlen == 1) {
+ ip++;
+ cur++;
+ continue;
+ }
+ offset = opt[cur].off;
+ cur += mlen;
+ litLength = (U32)(ip - anchor);
+
+ if (offset > ZSTD_REP_MOVE_OPT) {
+ rep[2] = rep[1];
+ rep[1] = rep[0];
+ rep[0] = offset - ZSTD_REP_MOVE_OPT;
+ offset--;
+ } else {
+ if (offset != 0) {
+ best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
+ if (offset != 1)
+ rep[2] = rep[1];
+ rep[1] = rep[0];
+ rep[0] = best_off;
+ }
+ if (litLength == 0)
+ offset--;
+ }
+
+ ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
+ ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
+ anchor = ip = ip + mlen;
+ }
+ } /* for (cur=0; cur < last_pos; ) */
+
+ /* Save reps for next block */
+ {
+ int i;
+ for (i = 0; i < ZSTD_REP_NUM; i++)
+ ctx->repToConfirm[i] = rep[i];
+ }
+
+ /* Last Literals */
+ {
+ size_t const lastLLSize = iend - anchor;
+ memcpy(seqStorePtr->lit, anchor, lastLLSize);
+ seqStorePtr->lit += lastLLSize;
+ }
+}
+
+FORCE_INLINE
+void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra)
+{
+ seqStore_t *seqStorePtr = &(ctx->seqStore);
+ const BYTE *const istart = (const BYTE *)src;
+ const BYTE *ip = istart;
+ const BYTE *anchor = istart;
+ const BYTE *const iend = istart + srcSize;
+ const BYTE *const ilimit = iend - 8;
+ const BYTE *const base = ctx->base;
+ const U32 lowestIndex = ctx->lowLimit;
+ const U32 dictLimit = ctx->dictLimit;
+ const BYTE *const prefixStart = base + dictLimit;
+ const BYTE *const dictBase = ctx->dictBase;
+ const BYTE *const dictEnd = dictBase + dictLimit;
+
+ const U32 maxSearches = 1U << ctx->params.cParams.searchLog;
+ const U32 sufficient_len = ctx->params.cParams.targetLength;
+ const U32 mls = ctx->params.cParams.searchLength;
+ const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4;
+
+ ZSTD_optimal_t *opt = seqStorePtr->priceTable;
+ ZSTD_match_t *matches = seqStorePtr->matchTable;
+ const BYTE *inr;
+
+ /* init */
+ U32 offset, rep[ZSTD_REP_NUM];
+ {
+ U32 i;
+ for (i = 0; i < ZSTD_REP_NUM; i++)
+ rep[i] = ctx->rep[i];
+ }
+
+ ctx->nextToUpdate3 = ctx->nextToUpdate;
+ ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize);
+ ip += (ip == prefixStart);
+
+ /* Match Loop */
+ while (ip < ilimit) {
+ U32 cur, match_num, last_pos, litlen, price;
+ U32 u, mlen, best_mlen, best_off, litLength;
+ U32 curr = (U32)(ip - base);
+ memset(opt, 0, sizeof(ZSTD_optimal_t));
+ last_pos = 0;
+ opt[0].litlen = (U32)(ip - anchor);
+
+ /* check repCode */
+ {
+ U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor);
+ for (i = (ip == anchor); i < last_i; i++) {
+ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i];
+ const U32 repIndex = (U32)(curr - repCur);
+ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
+ const BYTE *const repMatch = repBase + repIndex;
+ if ((repCur > 0 && repCur <= (S32)curr) &&
+ (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
+ && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) {
+ /* repcode detected we should take it */
+ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
+ mlen = (U32)ZSTD_count_2segments(ip + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch;
+
+ if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
+ best_mlen = mlen;
+ best_off = i;
+ cur = 0;
+ last_pos = 1;
+ goto _storeSequence;
+ }
+
+ best_off = i - (ip == anchor);
+ litlen = opt[0].litlen;
+ do {
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
+ if (mlen > last_pos || price < opt[mlen].price)
+ SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
+ mlen--;
+ } while (mlen >= minMatch);
+ }
+ }
+ }
+
+ match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, ip, iend, maxSearches, mls, matches, minMatch); /* first search (depth 0) */
+
+ if (!last_pos && !match_num) {
+ ip++;
+ continue;
+ }
+
+ {
+ U32 i;
+ for (i = 0; i < ZSTD_REP_NUM; i++)
+ opt[0].rep[i] = rep[i];
+ }
+ opt[0].mlen = 1;
+
+ if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
+ best_mlen = matches[match_num - 1].len;
+ best_off = matches[match_num - 1].off;
+ cur = 0;
+ last_pos = 1;
+ goto _storeSequence;
+ }
+
+ best_mlen = (last_pos) ? last_pos : minMatch;
+
+ /* set prices using matches at position = 0 */
+ for (u = 0; u < match_num; u++) {
+ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
+ best_mlen = matches[u].len;
+ litlen = opt[0].litlen;
+ while (mlen <= best_mlen) {
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
+ if (mlen > last_pos || price < opt[mlen].price)
+ SET_PRICE(mlen, mlen, matches[u].off, litlen, price);
+ mlen++;
+ }
+ }
+
+ if (last_pos < minMatch) {
+ ip++;
+ continue;
+ }
+
+ /* check further positions */
+ for (cur = 1; cur <= last_pos; cur++) {
+ inr = ip + cur;
+
+ if (opt[cur - 1].mlen == 1) {
+ litlen = opt[cur - 1].litlen + 1;
+ if (cur > litlen) {
+ price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen);
+ } else
+ price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor);
+ } else {
+ litlen = 1;
+ price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1);
+ }
+
+ if (cur > last_pos || price <= opt[cur].price)
+ SET_PRICE(cur, 1, 0, litlen, price);
+
+ if (cur == last_pos)
+ break;
+
+ if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */
+ continue;
+
+ mlen = opt[cur].mlen;
+ if (opt[cur].off > ZSTD_REP_MOVE_OPT) {
+ opt[cur].rep[2] = opt[cur - mlen].rep[1];
+ opt[cur].rep[1] = opt[cur - mlen].rep[0];
+ opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT;
+ } else {
+ opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2];
+ opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1];
+ opt[cur].rep[0] =
+ ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]);
+ }
+
+ best_mlen = minMatch;
+ {
+ U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1);
+ for (i = (mlen != 1); i < last_i; i++) {
+ const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i];
+ const U32 repIndex = (U32)(curr + cur - repCur);
+ const BYTE *const repBase = repIndex < dictLimit ? dictBase : base;
+ const BYTE *const repMatch = repBase + repIndex;
+ if ((repCur > 0 && repCur <= (S32)(curr + cur)) &&
+ (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
+ && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) {
+ /* repcode detected */
+ const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend;
+ mlen = (U32)ZSTD_count_2segments(inr + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch;
+
+ if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
+ best_mlen = mlen;
+ best_off = i;
+ last_pos = cur + 1;
+ goto _storeSequence;
+ }
+
+ best_off = i - (opt[cur].mlen != 1);
+ if (mlen > best_mlen)
+ best_mlen = mlen;
+
+ do {
+ if (opt[cur].mlen == 1) {
+ litlen = opt[cur].litlen;
+ if (cur > litlen) {
+ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen,
+ best_off, mlen - MINMATCH, ultra);
+ } else
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra);
+ } else {
+ litlen = 0;
+ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra);
+ }
+
+ if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
+ SET_PRICE(cur + mlen, mlen, i, litlen, price);
+ mlen--;
+ } while (mlen >= minMatch);
+ }
+ }
+ }
+
+ match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, inr, iend, maxSearches, mls, matches, minMatch);
+
+ if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) {
+ best_mlen = matches[match_num - 1].len;
+ best_off = matches[match_num - 1].off;
+ last_pos = cur + 1;
+ goto _storeSequence;
+ }
+
+ /* set prices using matches at position = cur */
+ for (u = 0; u < match_num; u++) {
+ mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen;
+ best_mlen = matches[u].len;
+
+ while (mlen <= best_mlen) {
+ if (opt[cur].mlen == 1) {
+ litlen = opt[cur].litlen;
+ if (cur > litlen)
+ price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen,
+ matches[u].off - 1, mlen - MINMATCH, ultra);
+ else
+ price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra);
+ } else {
+ litlen = 0;
+ price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra);
+ }
+
+ if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
+ SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
+
+ mlen++;
+ }
+ }
+ } /* for (cur = 1; cur <= last_pos; cur++) */
+
+ best_mlen = opt[last_pos].mlen;
+ best_off = opt[last_pos].off;
+ cur = last_pos - best_mlen;
+
+ /* store sequence */
+_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */
+ opt[0].mlen = 1;
+
+ while (1) {
+ mlen = opt[cur].mlen;
+ offset = opt[cur].off;
+ opt[cur].mlen = best_mlen;
+ opt[cur].off = best_off;
+ best_mlen = mlen;
+ best_off = offset;
+ if (mlen > cur)
+ break;
+ cur -= mlen;
+ }
+
+ for (u = 0; u <= last_pos;) {
+ u += opt[u].mlen;
+ }
+
+ for (cur = 0; cur < last_pos;) {
+ mlen = opt[cur].mlen;
+ if (mlen == 1) {
+ ip++;
+ cur++;
+ continue;
+ }
+ offset = opt[cur].off;
+ cur += mlen;
+ litLength = (U32)(ip - anchor);
+
+ if (offset > ZSTD_REP_MOVE_OPT) {
+ rep[2] = rep[1];
+ rep[1] = rep[0];
+ rep[0] = offset - ZSTD_REP_MOVE_OPT;
+ offset--;
+ } else {
+ if (offset != 0) {
+ best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]);
+ if (offset != 1)
+ rep[2] = rep[1];
+ rep[1] = rep[0];
+ rep[0] = best_off;
+ }
+
+ if (litLength == 0)
+ offset--;
+ }
+
+ ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
+ ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH);
+ anchor = ip = ip + mlen;
+ }
+ } /* for (cur=0; cur < last_pos; ) */
+
+ /* Save reps for next block */
+ {
+ int i;
+ for (i = 0; i < ZSTD_REP_NUM; i++)
+ ctx->repToConfirm[i] = rep[i];
+ }
+
+ /* Last Literals */
+ {
+ size_t lastLLSize = iend - anchor;
+ memcpy(seqStorePtr->lit, anchor, lastLLSize);
+ seqStorePtr->lit += lastLLSize;
+ }
+}
+
+#endif /* ZSTD_OPT_H_91842398743 */
--
2.15.1
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