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+/*
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+ * LZ4 - Fast LZ compression algorithm
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+ * Header File
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+ * Copyright (C) 2011-2023, Yann Collet.
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+
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+ BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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+
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+ Redistribution and use in source and binary forms, with or without
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+ modification, are permitted provided that the following conditions are
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+ met:
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+
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+ * Redistributions of source code must retain the above copyright
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+ notice, this list of conditions and the following disclaimer.
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+ * Redistributions in binary form must reproduce the above
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+ copyright notice, this list of conditions and the following disclaimer
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+ in the documentation and/or other materials provided with the
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+ distribution.
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+
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+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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+
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+ You can contact the author at :
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+ - LZ4 homepage : http://www.lz4.org
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+ - LZ4 source repository : https://github.com/lz4/lz4
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+*/
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+#if defined (__cplusplus)
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+extern "C" {
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+#endif
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+
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+#ifndef LZ4_H_2983827168210
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+#define LZ4_H_2983827168210
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+
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+/* --- Dependency --- */
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+#include <stddef.h> /* size_t */
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+
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+
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+/**
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+ Introduction
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+
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+ LZ4 is lossless compression algorithm, providing compression speed >500 MB/s per core,
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+ scalable with multi-cores CPU. It features an extremely fast decoder, with speed in
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+ multiple GB/s per core, typically reaching RAM speed limits on multi-core systems.
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+
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+ The LZ4 compression library provides in-memory compression and decompression functions.
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+ It gives full buffer control to user.
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+ Compression can be done in:
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+ - a single step (described as Simple Functions)
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+ - a single step, reusing a context (described in Advanced Functions)
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+ - unbounded multiple steps (described as Streaming compression)
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+
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+ lz4.h generates and decodes LZ4-compressed blocks (doc/lz4_Block_format.md).
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+ Decompressing such a compressed block requires additional metadata.
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+ Exact metadata depends on exact decompression function.
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+ For the typical case of LZ4_decompress_safe(),
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+ metadata includes block's compressed size, and maximum bound of decompressed size.
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+ Each application is free to encode and pass such metadata in whichever way it wants.
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+
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+ lz4.h only handle blocks, it can not generate Frames.
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+
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+ Blocks are different from Frames (doc/lz4_Frame_format.md).
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+ Frames bundle both blocks and metadata in a specified manner.
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+ Embedding metadata is required for compressed data to be self-contained and portable.
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+ Frame format is delivered through a companion API, declared in lz4frame.h.
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+ The `lz4` CLI can only manage frames.
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+*/
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+
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+/*^***************************************************************
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+* Export parameters
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+*****************************************************************/
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+/*
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+* LZ4_DLL_EXPORT :
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+* Enable exporting of functions when building a Windows DLL
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+* LZ4LIB_VISIBILITY :
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+* Control library symbols visibility.
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+*/
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+#ifndef LZ4LIB_VISIBILITY
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+# if defined(__GNUC__) && (__GNUC__ >= 4)
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+# define LZ4LIB_VISIBILITY __attribute__ ((visibility ("default")))
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+# else
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+# define LZ4LIB_VISIBILITY
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+# endif
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+#endif
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+#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1)
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+# define LZ4LIB_API __declspec(dllexport) LZ4LIB_VISIBILITY
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+#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1)
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+# define LZ4LIB_API __declspec(dllimport) LZ4LIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
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+#else
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+# define LZ4LIB_API LZ4LIB_VISIBILITY
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+#endif
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+
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+/*! LZ4_FREESTANDING :
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+ * When this macro is set to 1, it enables "freestanding mode" that is
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+ * suitable for typical freestanding environment which doesn't support
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+ * standard C library.
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+ *
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+ * - LZ4_FREESTANDING is a compile-time switch.
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+ * - It requires the following macros to be defined:
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+ * LZ4_memcpy, LZ4_memmove, LZ4_memset.
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+ * - It only enables LZ4/HC functions which don't use heap.
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+ * All LZ4F_* functions are not supported.
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+ * - See tests/freestanding.c to check its basic setup.
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+ */
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+#if defined(LZ4_FREESTANDING) && (LZ4_FREESTANDING == 1)
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+# define LZ4_HEAPMODE 0
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+# define LZ4HC_HEAPMODE 0
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+# define LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION 1
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+# if !defined(LZ4_memcpy)
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+# error "LZ4_FREESTANDING requires macro 'LZ4_memcpy'."
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+# endif
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+# if !defined(LZ4_memset)
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+# error "LZ4_FREESTANDING requires macro 'LZ4_memset'."
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+# endif
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+# if !defined(LZ4_memmove)
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+# error "LZ4_FREESTANDING requires macro 'LZ4_memmove'."
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+# endif
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+#elif ! defined(LZ4_FREESTANDING)
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+# define LZ4_FREESTANDING 0
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+#endif
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+
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+
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+/*------ Version ------*/
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+#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */
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+#define LZ4_VERSION_MINOR 10 /* for new (non-breaking) interface capabilities */
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+#define LZ4_VERSION_RELEASE 0 /* for tweaks, bug-fixes, or development */
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+
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+#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
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+
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+#define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE
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+#define LZ4_QUOTE(str) #str
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+#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str)
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+#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION) /* requires v1.7.3+ */
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+
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+LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version; requires v1.3.0+ */
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+LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; useful to check dll version; requires v1.7.5+ */
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+
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+
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+/*-************************************
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+* Tuning memory usage
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+**************************************/
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+/*!
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+ * LZ4_MEMORY_USAGE :
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+ * Can be selected at compile time, by setting LZ4_MEMORY_USAGE.
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+ * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB)
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+ * Increasing memory usage improves compression ratio, generally at the cost of speed.
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+ * Reduced memory usage may improve speed at the cost of ratio, thanks to better cache locality.
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+ * Default value is 14, for 16KB, which nicely fits into most L1 caches.
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+ */
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+#ifndef LZ4_MEMORY_USAGE
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+# define LZ4_MEMORY_USAGE LZ4_MEMORY_USAGE_DEFAULT
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+#endif
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+
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+/* These are absolute limits, they should not be changed by users */
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+#define LZ4_MEMORY_USAGE_MIN 10
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+#define LZ4_MEMORY_USAGE_DEFAULT 14
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+#define LZ4_MEMORY_USAGE_MAX 20
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+
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+#if (LZ4_MEMORY_USAGE < LZ4_MEMORY_USAGE_MIN)
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+# error "LZ4_MEMORY_USAGE is too small !"
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+#endif
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+
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+#if (LZ4_MEMORY_USAGE > LZ4_MEMORY_USAGE_MAX)
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+# error "LZ4_MEMORY_USAGE is too large !"
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+#endif
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+
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+/*-************************************
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+* Simple Functions
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+**************************************/
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+/*! LZ4_compress_default() :
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+ * Compresses 'srcSize' bytes from buffer 'src'
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+ * into already allocated 'dst' buffer of size 'dstCapacity'.
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+ * Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
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+ * It also runs faster, so it's a recommended setting.
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+ * If the function cannot compress 'src' into a more limited 'dst' budget,
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+ * compression stops *immediately*, and the function result is zero.
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+ * In which case, 'dst' content is undefined (invalid).
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+ * srcSize : max supported value is LZ4_MAX_INPUT_SIZE.
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+ * dstCapacity : size of buffer 'dst' (which must be already allocated)
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+ * @return : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
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+ * or 0 if compression fails
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+ * Note : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
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+ */
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+LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity);
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+
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+/*! LZ4_decompress_safe() :
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+ * @compressedSize : is the exact complete size of the compressed block.
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+ * @dstCapacity : is the size of destination buffer (which must be already allocated),
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+ * presumed an upper bound of decompressed size.
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+ * @return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
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+ * If destination buffer is not large enough, decoding will stop and output an error code (negative value).
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+ * If the source stream is detected malformed, the function will stop decoding and return a negative result.
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+ * Note 1 : This function is protected against malicious data packets :
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+ * it will never writes outside 'dst' buffer, nor read outside 'source' buffer,
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+ * even if the compressed block is maliciously modified to order the decoder to do these actions.
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+ * In such case, the decoder stops immediately, and considers the compressed block malformed.
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+ * Note 2 : compressedSize and dstCapacity must be provided to the function, the compressed block does not contain them.
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+ * The implementation is free to send / store / derive this information in whichever way is most beneficial.
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+ * If there is a need for a different format which bundles together both compressed data and its metadata, consider looking at lz4frame.h instead.
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+ */
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+LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSize, int dstCapacity);
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+
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+
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+/*-************************************
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+* Advanced Functions
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+**************************************/
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+#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
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+#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
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+
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+/*! LZ4_compressBound() :
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+ Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
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+ This function is primarily useful for memory allocation purposes (destination buffer size).
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+ Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example).
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+ Note that LZ4_compress_default() compresses faster when dstCapacity is >= LZ4_compressBound(srcSize)
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+ inputSize : max supported value is LZ4_MAX_INPUT_SIZE
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+ return : maximum output size in a "worst case" scenario
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+ or 0, if input size is incorrect (too large or negative)
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+*/
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+LZ4LIB_API int LZ4_compressBound(int inputSize);
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+
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+/*! LZ4_compress_fast() :
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+ Same as LZ4_compress_default(), but allows selection of "acceleration" factor.
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+ The larger the acceleration value, the faster the algorithm, but also the lesser the compression.
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+ It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed.
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+ An acceleration value of "1" is the same as regular LZ4_compress_default()
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+ Values <= 0 will be replaced by LZ4_ACCELERATION_DEFAULT (currently == 1, see lz4.c).
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+ Values > LZ4_ACCELERATION_MAX will be replaced by LZ4_ACCELERATION_MAX (currently == 65537, see lz4.c).
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+*/
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+LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
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+
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+
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+/*! LZ4_compress_fast_extState() :
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+ * Same as LZ4_compress_fast(), using an externally allocated memory space for its state.
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+ * Use LZ4_sizeofState() to know how much memory must be allocated,
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+ * and allocate it on 8-bytes boundaries (using `malloc()` typically).
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+ * Then, provide this buffer as `void* state` to compression function.
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+ */
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+LZ4LIB_API int LZ4_sizeofState(void);
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+LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
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+
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+/*! LZ4_compress_destSize() :
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+ * Reverse the logic : compresses as much data as possible from 'src' buffer
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+ * into already allocated buffer 'dst', of size >= 'dstCapacity'.
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+ * This function either compresses the entire 'src' content into 'dst' if it's large enough,
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+ * or fill 'dst' buffer completely with as much data as possible from 'src'.
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+ * note: acceleration parameter is fixed to "default".
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+ *
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+ * *srcSizePtr : in+out parameter. Initially contains size of input.
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+ * Will be modified to indicate how many bytes where read from 'src' to fill 'dst'.
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+ * New value is necessarily <= input value.
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+ * @return : Nb bytes written into 'dst' (necessarily <= dstCapacity)
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+ * or 0 if compression fails.
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+ *
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+ * Note : from v1.8.2 to v1.9.1, this function had a bug (fixed in v1.9.2+):
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+ * the produced compressed content could, in specific circumstances,
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+ * require to be decompressed into a destination buffer larger
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+ * by at least 1 byte than the content to decompress.
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+ * If an application uses `LZ4_compress_destSize()`,
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+ * it's highly recommended to update liblz4 to v1.9.2 or better.
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+ * If this can't be done or ensured,
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+ * the receiving decompression function should provide
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+ * a dstCapacity which is > decompressedSize, by at least 1 byte.
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+ * See https://github.com/lz4/lz4/issues/859 for details
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+ */
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+LZ4LIB_API int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize);
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+
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+/*! LZ4_decompress_safe_partial() :
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+ * Decompress an LZ4 compressed block, of size 'srcSize' at position 'src',
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+ * into destination buffer 'dst' of size 'dstCapacity'.
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+ * Up to 'targetOutputSize' bytes will be decoded.
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+ * The function stops decoding on reaching this objective.
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+ * This can be useful to boost performance
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+ * whenever only the beginning of a block is required.
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+ *
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+ * @return : the number of bytes decoded in `dst` (necessarily <= targetOutputSize)
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+ * If source stream is detected malformed, function returns a negative result.
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+ *
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+ * Note 1 : @return can be < targetOutputSize, if compressed block contains less data.
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+ *
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+ * Note 2 : targetOutputSize must be <= dstCapacity
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+ *
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+ * Note 3 : this function effectively stops decoding on reaching targetOutputSize,
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+ * so dstCapacity is kind of redundant.
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+ * This is because in older versions of this function,
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+ * decoding operation would still write complete sequences.
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+ * Therefore, there was no guarantee that it would stop writing at exactly targetOutputSize,
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+ * it could write more bytes, though only up to dstCapacity.
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+ * Some "margin" used to be required for this operation to work properly.
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+ * Thankfully, this is no longer necessary.
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+ * The function nonetheless keeps the same signature, in an effort to preserve API compatibility.
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+ *
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+ * Note 4 : If srcSize is the exact size of the block,
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+ * then targetOutputSize can be any value,
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+ * including larger than the block's decompressed size.
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+ * The function will, at most, generate block's decompressed size.
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+ *
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+ * Note 5 : If srcSize is _larger_ than block's compressed size,
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+ * then targetOutputSize **MUST** be <= block's decompressed size.
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+ * Otherwise, *silent corruption will occur*.
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+ */
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+LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcSize, int targetOutputSize, int dstCapacity);
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+
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+
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+/*-*********************************************
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+* Streaming Compression Functions
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+***********************************************/
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+typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */
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+
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+/*!
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+ Note about RC_INVOKED
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+
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+ - RC_INVOKED is predefined symbol of rc.exe (the resource compiler which is part of MSVC/Visual Studio).
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+ https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros
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+
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+ - Since rc.exe is a legacy compiler, it truncates long symbol (> 30 chars)
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+ and reports warning "RC4011: identifier truncated".
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+
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+ - To eliminate the warning, we surround long preprocessor symbol with
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+ "#if !defined(RC_INVOKED) ... #endif" block that means
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+ "skip this block when rc.exe is trying to read it".
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+*/
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+#if !defined(RC_INVOKED) /* https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros */
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+#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION)
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+LZ4LIB_API LZ4_stream_t* LZ4_createStream(void);
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+LZ4LIB_API int LZ4_freeStream (LZ4_stream_t* streamPtr);
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+#endif /* !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) */
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+#endif
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+
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+/*! LZ4_resetStream_fast() : v1.9.0+
|
|
|
+ * Use this to prepare an LZ4_stream_t for a new chain of dependent blocks
|
|
|
+ * (e.g., LZ4_compress_fast_continue()).
|
|
|
+ *
|
|
|
+ * An LZ4_stream_t must be initialized once before usage.
|
|
|
+ * This is automatically done when created by LZ4_createStream().
|
|
|
+ * However, should the LZ4_stream_t be simply declared on stack (for example),
|
|
|
+ * it's necessary to initialize it first, using LZ4_initStream().
|
|
|
+ *
|
|
|
+ * After init, start any new stream with LZ4_resetStream_fast().
|
|
|
+ * A same LZ4_stream_t can be re-used multiple times consecutively
|
|
|
+ * and compress multiple streams,
|
|
|
+ * provided that it starts each new stream with LZ4_resetStream_fast().
|
|
|
+ *
|
|
|
+ * LZ4_resetStream_fast() is much faster than LZ4_initStream(),
|
|
|
+ * but is not compatible with memory regions containing garbage data.
|
|
|
+ *
|
|
|
+ * Note: it's only useful to call LZ4_resetStream_fast()
|
|
|
+ * in the context of streaming compression.
|
|
|
+ * The *extState* functions perform their own resets.
|
|
|
+ * Invoking LZ4_resetStream_fast() before is redundant, and even counterproductive.
|
|
|
+ */
|
|
|
+LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr);
|
|
|
+
|
|
|
+/*! LZ4_loadDict() :
|
|
|
+ * Use this function to reference a static dictionary into LZ4_stream_t.
|
|
|
+ * The dictionary must remain available during compression.
|
|
|
+ * LZ4_loadDict() triggers a reset, so any previous data will be forgotten.
|
|
|
+ * The same dictionary will have to be loaded on decompression side for successful decoding.
|
|
|
+ * Dictionary are useful for better compression of small data (KB range).
|
|
|
+ * While LZ4 itself accepts any input as dictionary, dictionary efficiency is also a topic.
|
|
|
+ * When in doubt, employ the Zstandard's Dictionary Builder.
|
|
|
+ * Loading a size of 0 is allowed, and is the same as reset.
|
|
|
+ * @return : loaded dictionary size, in bytes (note: only the last 64 KB are loaded)
|
|
|
+ */
|
|
|
+LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
|
|
|
+
|
|
|
+/*! LZ4_loadDictSlow() : v1.10.0+
|
|
|
+ * Same as LZ4_loadDict(),
|
|
|
+ * but uses a bit more cpu to reference the dictionary content more thoroughly.
|
|
|
+ * This is expected to slightly improve compression ratio.
|
|
|
+ * The extra-cpu cost is likely worth it if the dictionary is re-used across multiple sessions.
|
|
|
+ * @return : loaded dictionary size, in bytes (note: only the last 64 KB are loaded)
|
|
|
+ */
|
|
|
+LZ4LIB_API int LZ4_loadDictSlow(LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
|
|
|
+
|
|
|
+/*! LZ4_attach_dictionary() : stable since v1.10.0
|
|
|
+ *
|
|
|
+ * This allows efficient re-use of a static dictionary multiple times.
|
|
|
+ *
|
|
|
+ * Rather than re-loading the dictionary buffer into a working context before
|
|
|
+ * each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a
|
|
|
+ * working LZ4_stream_t, this function introduces a no-copy setup mechanism,
|
|
|
+ * in which the working stream references @dictionaryStream in-place.
|
|
|
+ *
|
|
|
+ * Several assumptions are made about the state of @dictionaryStream.
|
|
|
+ * Currently, only states which have been prepared by LZ4_loadDict() or
|
|
|
+ * LZ4_loadDictSlow() should be expected to work.
|
|
|
+ *
|
|
|
+ * Alternatively, the provided @dictionaryStream may be NULL,
|
|
|
+ * in which case any existing dictionary stream is unset.
|
|
|
+ *
|
|
|
+ * If a dictionary is provided, it replaces any pre-existing stream history.
|
|
|
+ * The dictionary contents are the only history that can be referenced and
|
|
|
+ * logically immediately precede the data compressed in the first subsequent
|
|
|
+ * compression call.
|
|
|
+ *
|
|
|
+ * The dictionary will only remain attached to the working stream through the
|
|
|
+ * first compression call, at the end of which it is cleared.
|
|
|
+ * @dictionaryStream stream (and source buffer) must remain in-place / accessible / unchanged
|
|
|
+ * through the completion of the compression session.
|
|
|
+ *
|
|
|
+ * Note: there is no equivalent LZ4_attach_*() method on the decompression side
|
|
|
+ * because there is no initialization cost, hence no need to share the cost across multiple sessions.
|
|
|
+ * To decompress LZ4 blocks using dictionary, attached or not,
|
|
|
+ * just employ the regular LZ4_setStreamDecode() for streaming,
|
|
|
+ * or the stateless LZ4_decompress_safe_usingDict() for one-shot decompression.
|
|
|
+ */
|
|
|
+LZ4LIB_API void
|
|
|
+LZ4_attach_dictionary(LZ4_stream_t* workingStream,
|
|
|
+ const LZ4_stream_t* dictionaryStream);
|
|
|
+
|
|
|
+/*! LZ4_compress_fast_continue() :
|
|
|
+ * Compress 'src' content using data from previously compressed blocks, for better compression ratio.
|
|
|
+ * 'dst' buffer must be already allocated.
|
|
|
+ * If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
|
|
|
+ *
|
|
|
+ * @return : size of compressed block
|
|
|
+ * or 0 if there is an error (typically, cannot fit into 'dst').
|
|
|
+ *
|
|
|
+ * Note 1 : Each invocation to LZ4_compress_fast_continue() generates a new block.
|
|
|
+ * Each block has precise boundaries.
|
|
|
+ * Each block must be decompressed separately, calling LZ4_decompress_*() with relevant metadata.
|
|
|
+ * It's not possible to append blocks together and expect a single invocation of LZ4_decompress_*() to decompress them together.
|
|
|
+ *
|
|
|
+ * Note 2 : The previous 64KB of source data is __assumed__ to remain present, unmodified, at same address in memory !
|
|
|
+ *
|
|
|
+ * Note 3 : When input is structured as a double-buffer, each buffer can have any size, including < 64 KB.
|
|
|
+ * Make sure that buffers are separated, by at least one byte.
|
|
|
+ * This construction ensures that each block only depends on previous block.
|
|
|
+ *
|
|
|
+ * Note 4 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
|
|
|
+ *
|
|
|
+ * Note 5 : After an error, the stream status is undefined (invalid), it can only be reset or freed.
|
|
|
+ */
|
|
|
+LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
|
|
+
|
|
|
+/*! LZ4_saveDict() :
|
|
|
+ * If last 64KB data cannot be guaranteed to remain available at its current memory location,
|
|
|
+ * save it into a safer place (char* safeBuffer).
|
|
|
+ * This is schematically equivalent to a memcpy() followed by LZ4_loadDict(),
|
|
|
+ * but is much faster, because LZ4_saveDict() doesn't need to rebuild tables.
|
|
|
+ * @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error.
|
|
|
+ */
|
|
|
+LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize);
|
|
|
+
|
|
|
+
|
|
|
+/*-**********************************************
|
|
|
+* Streaming Decompression Functions
|
|
|
+* Bufferless synchronous API
|
|
|
+************************************************/
|
|
|
+typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* tracking context */
|
|
|
+
|
|
|
+/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
|
|
|
+ * creation / destruction of streaming decompression tracking context.
|
|
|
+ * A tracking context can be re-used multiple times.
|
|
|
+ */
|
|
|
+#if !defined(RC_INVOKED) /* https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros */
|
|
|
+#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION)
|
|
|
+LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void);
|
|
|
+LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);
|
|
|
+#endif /* !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) */
|
|
|
+#endif
|
|
|
+
|
|
|
+/*! LZ4_setStreamDecode() :
|
|
|
+ * An LZ4_streamDecode_t context can be allocated once and re-used multiple times.
|
|
|
+ * Use this function to start decompression of a new stream of blocks.
|
|
|
+ * A dictionary can optionally be set. Use NULL or size 0 for a reset order.
|
|
|
+ * Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
|
|
|
+ * @return : 1 if OK, 0 if error
|
|
|
+ */
|
|
|
+LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);
|
|
|
+
|
|
|
+/*! LZ4_decoderRingBufferSize() : v1.8.2+
|
|
|
+ * Note : in a ring buffer scenario (optional),
|
|
|
+ * blocks are presumed decompressed next to each other
|
|
|
+ * up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize),
|
|
|
+ * at which stage it resumes from beginning of ring buffer.
|
|
|
+ * When setting such a ring buffer for streaming decompression,
|
|
|
+ * provides the minimum size of this ring buffer
|
|
|
+ * to be compatible with any source respecting maxBlockSize condition.
|
|
|
+ * @return : minimum ring buffer size,
|
|
|
+ * or 0 if there is an error (invalid maxBlockSize).
|
|
|
+ */
|
|
|
+LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize);
|
|
|
+#define LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize) (65536 + 14 + (maxBlockSize)) /* for static allocation; maxBlockSize presumed valid */
|
|
|
+
|
|
|
+/*! LZ4_decompress_safe_continue() :
|
|
|
+ * This decoding function allows decompression of consecutive blocks in "streaming" mode.
|
|
|
+ * The difference with the usual independent blocks is that
|
|
|
+ * new blocks are allowed to find references into former blocks.
|
|
|
+ * A block is an unsplittable entity, and must be presented entirely to the decompression function.
|
|
|
+ * LZ4_decompress_safe_continue() only accepts one block at a time.
|
|
|
+ * It's modeled after `LZ4_decompress_safe()` and behaves similarly.
|
|
|
+ *
|
|
|
+ * @LZ4_streamDecode : decompression state, tracking the position in memory of past data
|
|
|
+ * @compressedSize : exact complete size of one compressed block.
|
|
|
+ * @dstCapacity : size of destination buffer (which must be already allocated),
|
|
|
+ * must be an upper bound of decompressed size.
|
|
|
+ * @return : number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
|
|
|
+ * If destination buffer is not large enough, decoding will stop and output an error code (negative value).
|
|
|
+ * If the source stream is detected malformed, the function will stop decoding and return a negative result.
|
|
|
+ *
|
|
|
+ * The last 64KB of previously decoded data *must* remain available and unmodified
|
|
|
+ * at the memory position where they were previously decoded.
|
|
|
+ * If less than 64KB of data has been decoded, all the data must be present.
|
|
|
+ *
|
|
|
+ * Special : if decompression side sets a ring buffer, it must respect one of the following conditions :
|
|
|
+ * - Decompression buffer size is _at least_ LZ4_decoderRingBufferSize(maxBlockSize).
|
|
|
+ * maxBlockSize is the maximum size of any single block. It can have any value > 16 bytes.
|
|
|
+ * In which case, encoding and decoding buffers do not need to be synchronized.
|
|
|
+ * Actually, data can be produced by any source compliant with LZ4 format specification, and respecting maxBlockSize.
|
|
|
+ * - Synchronized mode :
|
|
|
+ * Decompression buffer size is _exactly_ the same as compression buffer size,
|
|
|
+ * and follows exactly same update rule (block boundaries at same positions),
|
|
|
+ * and decoding function is provided with exact decompressed size of each block (exception for last block of the stream),
|
|
|
+ * _then_ decoding & encoding ring buffer can have any size, including small ones ( < 64 KB).
|
|
|
+ * - Decompression buffer is larger than encoding buffer, by a minimum of maxBlockSize more bytes.
|
|
|
+ * In which case, encoding and decoding buffers do not need to be synchronized,
|
|
|
+ * and encoding ring buffer can have any size, including small ones ( < 64 KB).
|
|
|
+ *
|
|
|
+ * Whenever these conditions are not possible,
|
|
|
+ * save the last 64KB of decoded data into a safe buffer where it can't be modified during decompression,
|
|
|
+ * then indicate where this data is saved using LZ4_setStreamDecode(), before decompressing next block.
|
|
|
+*/
|
|
|
+LZ4LIB_API int
|
|
|
+LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode,
|
|
|
+ const char* src, char* dst,
|
|
|
+ int srcSize, int dstCapacity);
|
|
|
+
|
|
|
+
|
|
|
+/*! LZ4_decompress_safe_usingDict() :
|
|
|
+ * Works the same as
|
|
|
+ * a combination of LZ4_setStreamDecode() followed by LZ4_decompress_safe_continue()
|
|
|
+ * However, it's stateless: it doesn't need any LZ4_streamDecode_t state.
|
|
|
+ * Dictionary is presumed stable : it must remain accessible and unmodified during decompression.
|
|
|
+ * Performance tip : Decompression speed can be substantially increased
|
|
|
+ * when dst == dictStart + dictSize.
|
|
|
+ */
|
|
|
+LZ4LIB_API int
|
|
|
+LZ4_decompress_safe_usingDict(const char* src, char* dst,
|
|
|
+ int srcSize, int dstCapacity,
|
|
|
+ const char* dictStart, int dictSize);
|
|
|
+
|
|
|
+/*! LZ4_decompress_safe_partial_usingDict() :
|
|
|
+ * Behaves the same as LZ4_decompress_safe_partial()
|
|
|
+ * with the added ability to specify a memory segment for past data.
|
|
|
+ * Performance tip : Decompression speed can be substantially increased
|
|
|
+ * when dst == dictStart + dictSize.
|
|
|
+ */
|
|
|
+LZ4LIB_API int
|
|
|
+LZ4_decompress_safe_partial_usingDict(const char* src, char* dst,
|
|
|
+ int compressedSize,
|
|
|
+ int targetOutputSize, int maxOutputSize,
|
|
|
+ const char* dictStart, int dictSize);
|
|
|
+
|
|
|
+#endif /* LZ4_H_2983827168210 */
|
|
|
+
|
|
|
+
|
|
|
+/*^*************************************
|
|
|
+ * !!!!!! STATIC LINKING ONLY !!!!!!
|
|
|
+ ***************************************/
|
|
|
+
|
|
|
+/*-****************************************************************************
|
|
|
+ * Experimental section
|
|
|
+ *
|
|
|
+ * Symbols declared in this section must be considered unstable. Their
|
|
|
+ * signatures or semantics may change, or they may be removed altogether in the
|
|
|
+ * future. They are therefore only safe to depend on when the caller is
|
|
|
+ * statically linked against the library.
|
|
|
+ *
|
|
|
+ * To protect against unsafe usage, not only are the declarations guarded,
|
|
|
+ * the definitions are hidden by default
|
|
|
+ * when building LZ4 as a shared/dynamic library.
|
|
|
+ *
|
|
|
+ * In order to access these declarations,
|
|
|
+ * define LZ4_STATIC_LINKING_ONLY in your application
|
|
|
+ * before including LZ4's headers.
|
|
|
+ *
|
|
|
+ * In order to make their implementations accessible dynamically, you must
|
|
|
+ * define LZ4_PUBLISH_STATIC_FUNCTIONS when building the LZ4 library.
|
|
|
+ ******************************************************************************/
|
|
|
+
|
|
|
+#ifdef LZ4_STATIC_LINKING_ONLY
|
|
|
+
|
|
|
+#ifndef LZ4_STATIC_3504398509
|
|
|
+#define LZ4_STATIC_3504398509
|
|
|
+
|
|
|
+#ifdef LZ4_PUBLISH_STATIC_FUNCTIONS
|
|
|
+# define LZ4LIB_STATIC_API LZ4LIB_API
|
|
|
+#else
|
|
|
+# define LZ4LIB_STATIC_API
|
|
|
+#endif
|
|
|
+
|
|
|
+
|
|
|
+/*! LZ4_compress_fast_extState_fastReset() :
|
|
|
+ * A variant of LZ4_compress_fast_extState().
|
|
|
+ *
|
|
|
+ * Using this variant avoids an expensive initialization step.
|
|
|
+ * It is only safe to call if the state buffer is known to be correctly initialized already
|
|
|
+ * (see above comment on LZ4_resetStream_fast() for a definition of "correctly initialized").
|
|
|
+ * From a high level, the difference is that
|
|
|
+ * this function initializes the provided state with a call to something like LZ4_resetStream_fast()
|
|
|
+ * while LZ4_compress_fast_extState() starts with a call to LZ4_resetStream().
|
|
|
+ */
|
|
|
+LZ4LIB_STATIC_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
|
|
+
|
|
|
+/*! LZ4_compress_destSize_extState() : introduced in v1.10.0
|
|
|
+ * Same as LZ4_compress_destSize(), but using an externally allocated state.
|
|
|
+ * Also: exposes @acceleration
|
|
|
+ */
|
|
|
+int LZ4_compress_destSize_extState(void* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize, int acceleration);
|
|
|
+
|
|
|
+/*! In-place compression and decompression
|
|
|
+ *
|
|
|
+ * It's possible to have input and output sharing the same buffer,
|
|
|
+ * for highly constrained memory environments.
|
|
|
+ * In both cases, it requires input to lay at the end of the buffer,
|
|
|
+ * and decompression to start at beginning of the buffer.
|
|
|
+ * Buffer size must feature some margin, hence be larger than final size.
|
|
|
+ *
|
|
|
+ * |<------------------------buffer--------------------------------->|
|
|
|
+ * |<-----------compressed data--------->|
|
|
|
+ * |<-----------decompressed size------------------>|
|
|
|
+ * |<----margin---->|
|
|
|
+ *
|
|
|
+ * This technique is more useful for decompression,
|
|
|
+ * since decompressed size is typically larger,
|
|
|
+ * and margin is short.
|
|
|
+ *
|
|
|
+ * In-place decompression will work inside any buffer
|
|
|
+ * which size is >= LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize).
|
|
|
+ * This presumes that decompressedSize > compressedSize.
|
|
|
+ * Otherwise, it means compression actually expanded data,
|
|
|
+ * and it would be more efficient to store such data with a flag indicating it's not compressed.
|
|
|
+ * This can happen when data is not compressible (already compressed, or encrypted).
|
|
|
+ *
|
|
|
+ * For in-place compression, margin is larger, as it must be able to cope with both
|
|
|
+ * history preservation, requiring input data to remain unmodified up to LZ4_DISTANCE_MAX,
|
|
|
+ * and data expansion, which can happen when input is not compressible.
|
|
|
+ * As a consequence, buffer size requirements are much higher,
|
|
|
+ * and memory savings offered by in-place compression are more limited.
|
|
|
+ *
|
|
|
+ * There are ways to limit this cost for compression :
|
|
|
+ * - Reduce history size, by modifying LZ4_DISTANCE_MAX.
|
|
|
+ * Note that it is a compile-time constant, so all compressions will apply this limit.
|
|
|
+ * Lower values will reduce compression ratio, except when input_size < LZ4_DISTANCE_MAX,
|
|
|
+ * so it's a reasonable trick when inputs are known to be small.
|
|
|
+ * - Require the compressor to deliver a "maximum compressed size".
|
|
|
+ * This is the `dstCapacity` parameter in `LZ4_compress*()`.
|
|
|
+ * When this size is < LZ4_COMPRESSBOUND(inputSize), then compression can fail,
|
|
|
+ * in which case, the return code will be 0 (zero).
|
|
|
+ * The caller must be ready for these cases to happen,
|
|
|
+ * and typically design a backup scheme to send data uncompressed.
|
|
|
+ * The combination of both techniques can significantly reduce
|
|
|
+ * the amount of margin required for in-place compression.
|
|
|
+ *
|
|
|
+ * In-place compression can work in any buffer
|
|
|
+ * which size is >= (maxCompressedSize)
|
|
|
+ * with maxCompressedSize == LZ4_COMPRESSBOUND(srcSize) for guaranteed compression success.
|
|
|
+ * LZ4_COMPRESS_INPLACE_BUFFER_SIZE() depends on both maxCompressedSize and LZ4_DISTANCE_MAX,
|
|
|
+ * so it's possible to reduce memory requirements by playing with them.
|
|
|
+ */
|
|
|
+
|
|
|
+#define LZ4_DECOMPRESS_INPLACE_MARGIN(compressedSize) (((compressedSize) >> 8) + 32)
|
|
|
+#define LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize) ((decompressedSize) + LZ4_DECOMPRESS_INPLACE_MARGIN(decompressedSize)) /**< note: presumes that compressedSize < decompressedSize. note2: margin is overestimated a bit, since it could use compressedSize instead */
|
|
|
+
|
|
|
+#ifndef LZ4_DISTANCE_MAX /* history window size; can be user-defined at compile time */
|
|
|
+# define LZ4_DISTANCE_MAX 65535 /* set to maximum value by default */
|
|
|
+#endif
|
|
|
+
|
|
|
+#define LZ4_COMPRESS_INPLACE_MARGIN (LZ4_DISTANCE_MAX + 32) /* LZ4_DISTANCE_MAX can be safely replaced by srcSize when it's smaller */
|
|
|
+#define LZ4_COMPRESS_INPLACE_BUFFER_SIZE(maxCompressedSize) ((maxCompressedSize) + LZ4_COMPRESS_INPLACE_MARGIN) /**< maxCompressedSize is generally LZ4_COMPRESSBOUND(inputSize), but can be set to any lower value, with the risk that compression can fail (return code 0(zero)) */
|
|
|
+
|
|
|
+#endif /* LZ4_STATIC_3504398509 */
|
|
|
+#endif /* LZ4_STATIC_LINKING_ONLY */
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+#ifndef LZ4_H_98237428734687
|
|
|
+#define LZ4_H_98237428734687
|
|
|
+
|
|
|
+/*-************************************************************
|
|
|
+ * Private Definitions
|
|
|
+ **************************************************************
|
|
|
+ * Do not use these definitions directly.
|
|
|
+ * They are only exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`.
|
|
|
+ * Accessing members will expose user code to API and/or ABI break in future versions of the library.
|
|
|
+ **************************************************************/
|
|
|
+#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
|
|
|
+#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
|
|
|
+#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */
|
|
|
+
|
|
|
+#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
|
|
|
+# include <stdint.h>
|
|
|
+ typedef int8_t LZ4_i8;
|
|
|
+ typedef uint8_t LZ4_byte;
|
|
|
+ typedef uint16_t LZ4_u16;
|
|
|
+ typedef uint32_t LZ4_u32;
|
|
|
+#else
|
|
|
+ typedef signed char LZ4_i8;
|
|
|
+ typedef unsigned char LZ4_byte;
|
|
|
+ typedef unsigned short LZ4_u16;
|
|
|
+ typedef unsigned int LZ4_u32;
|
|
|
+#endif
|
|
|
+
|
|
|
+/*! LZ4_stream_t :
|
|
|
+ * Never ever use below internal definitions directly !
|
|
|
+ * These definitions are not API/ABI safe, and may change in future versions.
|
|
|
+ * If you need static allocation, declare or allocate an LZ4_stream_t object.
|
|
|
+**/
|
|
|
+
|
|
|
+typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
|
|
|
+struct LZ4_stream_t_internal {
|
|
|
+ LZ4_u32 hashTable[LZ4_HASH_SIZE_U32];
|
|
|
+ const LZ4_byte* dictionary;
|
|
|
+ const LZ4_stream_t_internal* dictCtx;
|
|
|
+ LZ4_u32 currentOffset;
|
|
|
+ LZ4_u32 tableType;
|
|
|
+ LZ4_u32 dictSize;
|
|
|
+ /* Implicit padding to ensure structure is aligned */
|
|
|
+};
|
|
|
+
|
|
|
+#define LZ4_STREAM_MINSIZE ((1UL << (LZ4_MEMORY_USAGE)) + 32) /* static size, for inter-version compatibility */
|
|
|
+union LZ4_stream_u {
|
|
|
+ char minStateSize[LZ4_STREAM_MINSIZE];
|
|
|
+ LZ4_stream_t_internal internal_donotuse;
|
|
|
+}; /* previously typedef'd to LZ4_stream_t */
|
|
|
+
|
|
|
+
|
|
|
+/*! LZ4_initStream() : v1.9.0+
|
|
|
+ * An LZ4_stream_t structure must be initialized at least once.
|
|
|
+ * This is automatically done when invoking LZ4_createStream(),
|
|
|
+ * but it's not when the structure is simply declared on stack (for example).
|
|
|
+ *
|
|
|
+ * Use LZ4_initStream() to properly initialize a newly declared LZ4_stream_t.
|
|
|
+ * It can also initialize any arbitrary buffer of sufficient size,
|
|
|
+ * and will @return a pointer of proper type upon initialization.
|
|
|
+ *
|
|
|
+ * Note : initialization fails if size and alignment conditions are not respected.
|
|
|
+ * In which case, the function will @return NULL.
|
|
|
+ * Note2: An LZ4_stream_t structure guarantees correct alignment and size.
|
|
|
+ * Note3: Before v1.9.0, use LZ4_resetStream() instead
|
|
|
+**/
|
|
|
+LZ4LIB_API LZ4_stream_t* LZ4_initStream (void* stateBuffer, size_t size);
|
|
|
+
|
|
|
+
|
|
|
+/*! LZ4_streamDecode_t :
|
|
|
+ * Never ever use below internal definitions directly !
|
|
|
+ * These definitions are not API/ABI safe, and may change in future versions.
|
|
|
+ * If you need static allocation, declare or allocate an LZ4_streamDecode_t object.
|
|
|
+**/
|
|
|
+typedef struct {
|
|
|
+ const LZ4_byte* externalDict;
|
|
|
+ const LZ4_byte* prefixEnd;
|
|
|
+ size_t extDictSize;
|
|
|
+ size_t prefixSize;
|
|
|
+} LZ4_streamDecode_t_internal;
|
|
|
+
|
|
|
+#define LZ4_STREAMDECODE_MINSIZE 32
|
|
|
+union LZ4_streamDecode_u {
|
|
|
+ char minStateSize[LZ4_STREAMDECODE_MINSIZE];
|
|
|
+ LZ4_streamDecode_t_internal internal_donotuse;
|
|
|
+} ; /* previously typedef'd to LZ4_streamDecode_t */
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*-************************************
|
|
|
+* Obsolete Functions
|
|
|
+**************************************/
|
|
|
+
|
|
|
+/*! Deprecation warnings
|
|
|
+ *
|
|
|
+ * Deprecated functions make the compiler generate a warning when invoked.
|
|
|
+ * This is meant to invite users to update their source code.
|
|
|
+ * Should deprecation warnings be a problem, it is generally possible to disable them,
|
|
|
+ * typically with -Wno-deprecated-declarations for gcc
|
|
|
+ * or _CRT_SECURE_NO_WARNINGS in Visual.
|
|
|
+ *
|
|
|
+ * Another method is to define LZ4_DISABLE_DEPRECATE_WARNINGS
|
|
|
+ * before including the header file.
|
|
|
+ */
|
|
|
+#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS
|
|
|
+# define LZ4_DEPRECATED(message) /* disable deprecation warnings */
|
|
|
+#else
|
|
|
+# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
|
|
|
+# define LZ4_DEPRECATED(message) [[deprecated(message)]]
|
|
|
+# elif defined(_MSC_VER)
|
|
|
+# define LZ4_DEPRECATED(message) __declspec(deprecated(message))
|
|
|
+# elif defined(__clang__) || (defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 45))
|
|
|
+# define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
|
|
|
+# elif defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 31)
|
|
|
+# define LZ4_DEPRECATED(message) __attribute__((deprecated))
|
|
|
+# else
|
|
|
+# pragma message("WARNING: LZ4_DEPRECATED needs custom implementation for this compiler")
|
|
|
+# define LZ4_DEPRECATED(message) /* disabled */
|
|
|
+# endif
|
|
|
+#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */
|
|
|
+
|
|
|
+/*! Obsolete compression functions (since v1.7.3) */
|
|
|
+LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress (const char* src, char* dest, int srcSize);
|
|
|
+LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* src, char* dest, int srcSize, int maxOutputSize);
|
|
|
+LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize);
|
|
|
+LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
|
|
|
+LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
|
|
|
+LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
|
|
|
+
|
|
|
+/*! Obsolete decompression functions (since v1.8.0) */
|
|
|
+LZ4_DEPRECATED("use LZ4_decompress_fast() instead") LZ4LIB_API int LZ4_uncompress (const char* source, char* dest, int outputSize);
|
|
|
+LZ4_DEPRECATED("use LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize);
|
|
|
+
|
|
|
+/* Obsolete streaming functions (since v1.7.0)
|
|
|
+ * degraded functionality; do not use!
|
|
|
+ *
|
|
|
+ * In order to perform streaming compression, these functions depended on data
|
|
|
+ * that is no longer tracked in the state. They have been preserved as well as
|
|
|
+ * possible: using them will still produce a correct output. However, they don't
|
|
|
+ * actually retain any history between compression calls. The compression ratio
|
|
|
+ * achieved will therefore be no better than compressing each chunk
|
|
|
+ * independently.
|
|
|
+ */
|
|
|
+LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API void* LZ4_create (char* inputBuffer);
|
|
|
+LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API int LZ4_sizeofStreamState(void);
|
|
|
+LZ4_DEPRECATED("Use LZ4_resetStream() instead") LZ4LIB_API int LZ4_resetStreamState(void* state, char* inputBuffer);
|
|
|
+LZ4_DEPRECATED("Use LZ4_saveDict() instead") LZ4LIB_API char* LZ4_slideInputBuffer (void* state);
|
|
|
+
|
|
|
+/*! Obsolete streaming decoding functions (since v1.7.0) */
|
|
|
+LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") LZ4LIB_API int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize);
|
|
|
+LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") LZ4LIB_API int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize);
|
|
|
+
|
|
|
+/*! Obsolete LZ4_decompress_fast variants (since v1.9.0) :
|
|
|
+ * These functions used to be faster than LZ4_decompress_safe(),
|
|
|
+ * but this is no longer the case. They are now slower.
|
|
|
+ * This is because LZ4_decompress_fast() doesn't know the input size,
|
|
|
+ * and therefore must progress more cautiously into the input buffer to not read beyond the end of block.
|
|
|
+ * On top of that `LZ4_decompress_fast()` is not protected vs malformed or malicious inputs, making it a security liability.
|
|
|
+ * As a consequence, LZ4_decompress_fast() is strongly discouraged, and deprecated.
|
|
|
+ *
|
|
|
+ * The last remaining LZ4_decompress_fast() specificity is that
|
|
|
+ * it can decompress a block without knowing its compressed size.
|
|
|
+ * Such functionality can be achieved in a more secure manner
|
|
|
+ * by employing LZ4_decompress_safe_partial().
|
|
|
+ *
|
|
|
+ * Parameters:
|
|
|
+ * originalSize : is the uncompressed size to regenerate.
|
|
|
+ * `dst` must be already allocated, its size must be >= 'originalSize' bytes.
|
|
|
+ * @return : number of bytes read from source buffer (== compressed size).
|
|
|
+ * The function expects to finish at block's end exactly.
|
|
|
+ * If the source stream is detected malformed, the function stops decoding and returns a negative result.
|
|
|
+ * note : LZ4_decompress_fast*() requires originalSize. Thanks to this information, it never writes past the output buffer.
|
|
|
+ * However, since it doesn't know its 'src' size, it may read an unknown amount of input, past input buffer bounds.
|
|
|
+ * Also, since match offsets are not validated, match reads from 'src' may underflow too.
|
|
|
+ * These issues never happen if input (compressed) data is correct.
|
|
|
+ * But they may happen if input data is invalid (error or intentional tampering).
|
|
|
+ * As a consequence, use these functions in trusted environments with trusted data **only**.
|
|
|
+ */
|
|
|
+LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_partial() instead")
|
|
|
+LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize);
|
|
|
+LZ4_DEPRECATED("This function is deprecated and unsafe. Consider migrating towards LZ4_decompress_safe_continue() instead. "
|
|
|
+ "Note that the contract will change (requires block's compressed size, instead of decompressed size)")
|
|
|
+LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);
|
|
|
+LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_partial_usingDict() instead")
|
|
|
+LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);
|
|
|
+
|
|
|
+/*! LZ4_resetStream() :
|
|
|
+ * An LZ4_stream_t structure must be initialized at least once.
|
|
|
+ * This is done with LZ4_initStream(), or LZ4_resetStream().
|
|
|
+ * Consider switching to LZ4_initStream(),
|
|
|
+ * invoking LZ4_resetStream() will trigger deprecation warnings in the future.
|
|
|
+ */
|
|
|
+LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
|
|
|
+
|
|
|
+
|
|
|
+#endif /* LZ4_H_98237428734687 */
|
|
|
+
|
|
|
+
|
|
|
+#if defined (__cplusplus)
|
|
|
+}
|
|
|
+#endif
|