VC2022编译的zstd v1.4.7

/* * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc. * All rights reserved. * * This source code is licensed under both the BSD-style license (found in the * LICENSE file in the root directory of this source tree) and the GPLv2 (found * in the COPYING file in the root directory of this source tree). * You may select, at your option, one of the above-listed licenses. */ #if defined (__cplusplus) extern "C" { #endif #ifndef ZSTD_H_235446 #define ZSTD_H_235446 /* ====== Dependency ======*/ #include <limits.h> /* INT_MAX */ #include <stddef.h> /* size_t */ /* ===== ZSTDLIB_API : control library symbols visibility ===== */ #ifndef ZSTDLIB_VISIBILITY # if defined(__GNUC__) && (__GNUC__ >= 4) # define ZSTDLIB_VISIBILITY __attribute__ ((visibility ("default"))) # else # define ZSTDLIB_VISIBILITY # endif #endif #if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1) # define ZSTDLIB_API __declspec(dllexport) ZSTDLIB_VISIBILITY #elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1) # define ZSTDLIB_API __declspec(dllimport) ZSTDLIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/ #else # define ZSTDLIB_API ZSTDLIB_VISIBILITY #endif /******************************************************************************* 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 regular compression levels from 1 up to ZSTD_maxCLevel(), which is currently 22. Levels >= 20, labeled `--ultra`, should be used with caution, as they require more memory. The library also offers negative compression levels, which extend the range of speed vs. ratio preferences. The lower the level, the faster the speed (at the cost of compression). Compression can be done in: - a single step (described as Simple API) - a single step, reusing a context (described as Explicit context) - unbounded multiple steps (described as Streaming compression) The compression ratio achievable on small data can be highly improved using a dictionary. Dictionary compression can be performed in: - a single step (described as Simple dictionary API) - a single step, reusing a dictionary (described as Bulk-processing dictionary API) Advanced experimental functions can be accessed using `#define ZSTD_STATIC_LINKING_ONLY` before including zstd.h. Advanced experimental APIs should never be used with a dynamically-linked library. They are not "stable"; their definitions or signatures may change in the future. Only static linking is allowed. *******************************************************************************/ /*------ Version ------*/ #define ZSTD_VERSION_MAJOR 1 #define ZSTD_VERSION_MINOR 4 #define ZSTD_VERSION_RELEASE 7 #define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE) /*! ZSTD_versionNumber() : * Return runtime library version, the value is (MAJOR*100*100 + MINOR*100 + RELEASE). */ ZSTDLIB_API unsigned ZSTD_versionNumber(void); #define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE #define ZSTD_QUOTE(str) #str #define ZSTD_EXPAND_AND_QUOTE(str) ZSTD_QUOTE(str) #define ZSTD_VERSION_STRING ZSTD_EXPAND_AND_QUOTE(ZSTD_LIB_VERSION) /*! ZSTD_versionString() : * Return runtime library version, like "1.4.5". Requires v1.3.0+. */ ZSTDLIB_API const char* ZSTD_versionString(void); /* ************************************* * Default constant ***************************************/ #ifndef ZSTD_CLEVEL_DEFAULT # define ZSTD_CLEVEL_DEFAULT 3 #endif /* ************************************* * Constants ***************************************/ /* All magic numbers are supposed read/written to/from files/memory using little-endian convention */ #define ZSTD_MAGICNUMBER 0xFD2FB528 /* valid since v0.8.0 */ #define ZSTD_MAGIC_DICTIONARY 0xEC30A437 /* valid since v0.7.0 */ #define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50 /* all 16 values, from 0x184D2A50 to 0x184D2A5F, signal the beginning of a skippable frame */ #define ZSTD_MAGIC_SKIPPABLE_MASK 0xFFFFFFF0 #define ZSTD_BLOCKSIZELOG_MAX 17 #define ZSTD_BLOCKSIZE_MAX (1<<ZSTD_BLOCKSIZELOG_MAX) /*************************************** * Simple API ***************************************/ /*! ZSTD_compress() : * Compresses `src` content as a single zstd compressed frame into already allocated `dst`. * Hint : compression runs faster if `dstCapacity` >= `ZSTD_compressBound(srcSize)`. * @return : compressed size written into `dst` (<= `dstCapacity), * or an error code if it fails (which can be tested using ZSTD_isError()). */ ZSTDLIB_API size_t ZSTD_compress( void* dst, size_t dstCapacity, const void* src, size_t srcSize, int compressionLevel); /*! ZSTD_decompress() : * `compressedSize` : must be the _exact_ size of some number of compressed and/or skippable frames. * `dstCapacity` is an upper bound of originalSize to regenerate. * If user cannot imply a maximum upper bound, it's better to use streaming mode to decompress data. * @return : the number of bytes decompressed into `dst` (<= `dstCapacity`), * or an errorCode if it fails (which can be tested using ZSTD_isError()). */ ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity, const void* src, size_t compressedSize); /*! ZSTD_getFrameContentSize() : requires v1.3.0+ * `src` should point to the start of a ZSTD encoded frame. * `srcSize` must be at least as large as the frame header. * hint : any size >= `ZSTD_frameHeaderSize_max` is large enough. * @return : - decompressed size of `src` frame content, if known * - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined * - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) * note 1 : a 0 return value means the frame is valid but "empty". * note 2 : decompressed size is an optional field, it may not be present, typically in streaming mode. * When `return==ZSTD_CONTENTSIZE_UNKNOWN`, data to decompress could be any size. * In which case, it's necessary to use streaming mode to decompress data. * Optionally, application can rely on some implicit limit, * as ZSTD_decompress() only needs an upper bound of decompressed size. * (For example, data could be necessarily cut into blocks <= 16 KB). * note 3 : decompressed size is always present when compression is completed using single-pass functions, * such as ZSTD_compress(), ZSTD_compressCCtx() ZSTD_compress_usingDict() or ZSTD_compress_usingCDict(). * note 4 : decompressed size can be very large (64-bits value), * potentially larger than what local system can handle as a single memory segment. * In which case, it's necessary to use streaming mode to decompress data. * note 5 : If source is untrusted, decompressed size could be wrong or intentionally modified. * Always ensure return value fits within application's authorized limits. * Each application can set its own limits. * note 6 : This function replaces ZSTD_getDecompressedSize() */ #define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1) #define ZSTD_CONTENTSIZE_ERROR (0ULL - 2) ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize); /*! ZSTD_getDecompressedSize() : * NOTE: This function is now obsolete, in favor of ZSTD_getFrameContentSize(). * Both functions work the same way, but ZSTD_getDecompressedSize() blends * "empty", "unknown"