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607 lines
30 KiB
C
607 lines
30 KiB
C
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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) 2011-2017, Yann Collet.
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BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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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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* 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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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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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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#ifndef LZ4_H_2983827168210
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#define LZ4_H_2983827168210
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/* --- Dependency --- */
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#include <stddef.h> /* size_t */
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/**
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Introduction
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LZ4 is lossless compression algorithm, providing compression speed at 400 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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The LZ4 compression library provides in-memory compression and decompression functions.
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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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lz4.h provides block compression functions. It gives full buffer control to user.
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Decompressing an lz4-compressed block also requires metadata (such as compressed size).
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Each application is free to encode such metadata in whichever way it wants.
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An additional format, called LZ4 frame specification (doc/lz4_Frame_format.md),
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take care of encoding standard metadata alongside LZ4-compressed blocks.
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If your application requires interoperability, it's recommended to use it.
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A library is provided to take care of it, see lz4frame.h.
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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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/*------ Version ------*/
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#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */
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#define LZ4_VERSION_MINOR 8 /* for new (non-breaking) interface capabilities */
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#define LZ4_VERSION_RELEASE 2 /* for tweaks, bug-fixes, or development */
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#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
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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)
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LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version */
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LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; unseful to check dll version */
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/*-************************************
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* Tuning parameter
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**************************************/
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/*!
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* LZ4_MEMORY_USAGE :
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* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
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* Increasing memory usage improves compression ratio
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* Reduced memory usage may improve speed, thanks to cache effect
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* Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
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*/
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#ifndef LZ4_MEMORY_USAGE
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# define LZ4_MEMORY_USAGE 14
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#endif
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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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Note : as a consequence, 'dst' content is not valid.
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Note 2 : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
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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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LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity);
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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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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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This function is protected against malicious data packets.
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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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* 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 ACCELERATION_DEFAULT (currently == 1, 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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LZ4_compress_fast_extState() :
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Same compression function, just using an externally allocated memory space to store compression 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 it 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 'targetDestSize'.
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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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*srcSizePtr : will be modified to indicate how many bytes where read from 'src' to fill 'dst'.
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New value is necessarily <= old value.
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return : Nb bytes written into 'dst' (necessarily <= targetDestSize)
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or 0 if compression fails
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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_fast() : **unsafe!**
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This function is a bit faster than LZ4_decompress_safe(),
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but it may misbehave on malformed input because it doesn't perform full validation of compressed data.
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originalSize : is the uncompressed size to regenerate
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Destination buffer must be already allocated, and its size must be >= 'originalSize' bytes.
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return : number of bytes read from source buffer (== compressed size).
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If the source stream is detected malformed, the function stops decoding and return a negative result.
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note : This function is only usable if the originalSize of uncompressed data is known in advance.
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The caller should also check that all the compressed input has been consumed properly,
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i.e. that the return value matches the size of the buffer with compressed input.
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The function never writes past the output buffer. However, since it doesn't know its 'src' size,
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it may read past the intended input. Also, because match offsets are not validated during decoding,
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reads from 'src' may underflow. Use this function in trusted environment **only**.
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*/
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LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize);
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/*!
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LZ4_decompress_safe_partial() :
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This function decompress a compressed block of size 'srcSize' at position 'src'
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into destination buffer 'dst' of size 'dstCapacity'.
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The function will decompress a minimum of 'targetOutputSize' bytes, and stop after that.
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However, it's not accurate, and may write more than 'targetOutputSize' (but always <= dstCapacity).
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@return : the number of bytes decoded in the destination buffer (necessarily <= dstCapacity)
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Note : this number can also be < targetOutputSize, if compressed block contains less data.
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Therefore, always control how many bytes were decoded.
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If source stream is detected malformed, function returns a negative result.
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This function is protected against malicious data packets.
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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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* 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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/*! LZ4_createStream() and LZ4_freeStream() :
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* LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure.
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* LZ4_freeStream() releases its memory.
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*/
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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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/*! LZ4_resetStream() :
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* An LZ4_stream_t structure can be allocated once and re-used multiple times.
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* Use this function to start compressing a new stream.
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*/
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LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
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/*! LZ4_loadDict() :
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* Use this function to load a static dictionary into LZ4_stream_t.
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* Any previous data will be forgotten, only 'dictionary' will remain in memory.
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* Loading a size of 0 is allowed, and is the same as reset.
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* @return : dictionary size, in bytes (necessarily <= 64 KB)
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*/
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LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
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/*! LZ4_compress_fast_continue() :
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* Compress 'src' content using data from previously compressed blocks, for better compression ratio.
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* 'dst' buffer must be already allocated.
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* If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
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*
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* Important : The previous 64KB of compressed data is assumed to remain present and unmodified in memory!
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*
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* Special 1 : When input is a double-buffer, they can have any size, including < 64 KB.
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* Make sure that buffers are separated by at least one byte.
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* This way, each block only depends on previous block.
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* Special 2 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
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*
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* @return : size of compressed block
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* or 0 if there is an error (typically, cannot fit into 'dst').
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* After an error, the stream status is invalid, it can only be reset or freed.
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*/
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LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
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/*! LZ4_saveDict() :
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* If last 64KB data cannot be guaranteed to remain available at its current memory location,
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* save it into a safer place (char* safeBuffer).
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* This is schematically equivalent to a memcpy() followed by LZ4_loadDict(),
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* but is much faster, because LZ4_saveDict() doesn't need to rebuild tables.
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* @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error.
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*/
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LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize);
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/*-**********************************************
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* Streaming Decompression Functions
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* Bufferless synchronous API
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************************************************/
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typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* tracking context */
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/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
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* creation / destruction of streaming decompression tracking context.
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* A tracking context can be re-used multiple times.
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*/
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LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void);
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LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);
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/*! LZ4_setStreamDecode() :
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* An LZ4_streamDecode_t context can be allocated once and re-used multiple times.
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* Use this function to start decompression of a new stream of blocks.
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* A dictionary can optionnally be set. Use NULL or size 0 for a reset order.
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* Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
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* @return : 1 if OK, 0 if error
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*/
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LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);
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/*! LZ4_decoderRingBufferSize() : v1.8.2
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* Note : in a ring buffer scenario (optional),
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* blocks are presumed decompressed next to each other
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* up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize),
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* at which stage it resumes from beginning of ring buffer.
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* When setting such a ring buffer for streaming decompression,
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* provides the minimum size of this ring buffer
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* to be compatible with any source respecting maxBlockSize condition.
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* @return : minimum ring buffer size,
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* or 0 if there is an error (invalid maxBlockSize).
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*/
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LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize);
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#define LZ4_DECODER_RING_BUFFER_SIZE(mbs) (65536 + 14 + (mbs)) /* for static allocation; mbs presumed valid */
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/*! LZ4_decompress_*_continue() :
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* These decoding functions allow decompression of consecutive blocks in "streaming" mode.
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* A block is an unsplittable entity, it must be presented entirely to a decompression function.
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* Decompression functions only accepts one block at a time.
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* The last 64KB of previously decoded data *must* remain available and unmodified at the memory position where they were decoded.
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* If less than 64KB of data has been decoded, all the data must be present.
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*
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* Special : if decompression side sets a ring buffer, it must respect one of the following conditions :
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* - Decompression buffer size is _at least_ LZ4_decoderRingBufferSize(maxBlockSize).
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* maxBlockSize is the maximum size of any single block. It can have any value > 16 bytes.
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* In which case, encoding and decoding buffers do not need to be synchronized.
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* Actually, data can be produced by any source compliant with LZ4 format specification, and respecting maxBlockSize.
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* - Synchronized mode :
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* Decompression buffer size is _exactly_ the same as compression buffer size,
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* and follows exactly same update rule (block boundaries at same positions),
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* and decoding function is provided with exact decompressed size of each block (exception for last block of the stream),
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* _then_ decoding & encoding ring buffer can have any size, including small ones ( < 64 KB).
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* - Decompression buffer is larger than encoding buffer, by a minimum of maxBlockSize more bytes.
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* In which case, encoding and decoding buffers do not need to be synchronized,
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* and encoding ring buffer can have any size, including small ones ( < 64 KB).
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*
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* 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);
|
||
|
LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);
|
||
|
|
||
|
|
||
|
/*! LZ4_decompress_*_usingDict() :
|
||
|
* These decoding functions work the same as
|
||
|
* a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue()
|
||
|
* They are stand-alone, and don't need an LZ4_streamDecode_t structure.
|
||
|
* Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
|
||
|
*/
|
||
|
LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* src, char* dst, int srcSize, int dstCapcity, const char* dictStart, int dictSize);
|
||
|
LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);
|
||
|
|
||
|
|
||
|
/*^**********************************************
|
||
|
* !!!!!! STATIC LINKING ONLY !!!!!!
|
||
|
***********************************************/
|
||
|
|
||
|
/*-************************************
|
||
|
* Unstable declarations
|
||
|
**************************************
|
||
|
* Declarations in this section should be considered unstable.
|
||
|
* Use at your own peril, etc., etc.
|
||
|
* They may be removed in the future.
|
||
|
* Their signatures may change.
|
||
|
**************************************/
|
||
|
|
||
|
#ifdef LZ4_STATIC_LINKING_ONLY
|
||
|
|
||
|
/*! LZ4_resetStream_fast() :
|
||
|
* Use this, like LZ4_resetStream(), to prepare a context for a new chain of
|
||
|
* calls to a streaming API (e.g., LZ4_compress_fast_continue()).
|
||
|
*
|
||
|
* Note:
|
||
|
* Using this in advance of a non- streaming-compression function is redundant,
|
||
|
* and potentially bad for performance, since they all perform their own custom
|
||
|
* reset internally.
|
||
|
*
|
||
|
* Differences from LZ4_resetStream():
|
||
|
* When an LZ4_stream_t is known to be in a internally coherent state,
|
||
|
* it can often be prepared for a new compression with almost no work, only
|
||
|
* sometimes falling back to the full, expensive reset that is always required
|
||
|
* when the stream is in an indeterminate state (i.e., the reset performed by
|
||
|
* LZ4_resetStream()).
|
||
|
*
|
||
|
* LZ4_streams are guaranteed to be in a valid state when:
|
||
|
* - returned from LZ4_createStream()
|
||
|
* - reset by LZ4_resetStream()
|
||
|
* - memset(stream, 0, sizeof(LZ4_stream_t)), though this is discouraged
|
||
|
* - the stream was in a valid state and was reset by LZ4_resetStream_fast()
|
||
|
* - the stream was in a valid state and was then used in any compression call
|
||
|
* that returned success
|
||
|
* - the stream was in an indeterminate state and was used in a compression
|
||
|
* call that fully reset the state (e.g., LZ4_compress_fast_extState()) and
|
||
|
* that returned success
|
||
|
*
|
||
|
* When a stream isn't known to be in a valid state, it is not safe to pass to
|
||
|
* any fastReset or streaming function. It must first be cleansed by the full
|
||
|
* LZ4_resetStream().
|
||
|
*/
|
||
|
LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr);
|
||
|
|
||
|
/*! 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_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||
|
|
||
|
/*! LZ4_attach_dictionary() :
|
||
|
* This is an experimental API that allows for the efficient use of a
|
||
|
* static dictionary many 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 the dictionary stream in-place.
|
||
|
*
|
||
|
* Several assumptions are made about the state of the dictionary stream.
|
||
|
* Currently, only streams which have been prepared by LZ4_loadDict() should
|
||
|
* be expected to work.
|
||
|
*
|
||
|
* Alternatively, the provided dictionary stream pointer 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. The dictionary
|
||
|
* stream (and source buffer) must remain in-place / accessible / unchanged
|
||
|
* through the completion of the first compression call on the stream.
|
||
|
*/
|
||
|
LZ4LIB_API void LZ4_attach_dictionary(LZ4_stream_t *working_stream, const LZ4_stream_t *dictionary_stream);
|
||
|
|
||
|
#endif
|
||
|
|
||
|
/*-************************************
|
||
|
* Private definitions
|
||
|
**************************************
|
||
|
* Do not use these definitions.
|
||
|
* They are exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`.
|
||
|
* Using these definitions will expose 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 struct LZ4_stream_t_internal LZ4_stream_t_internal;
|
||
|
struct LZ4_stream_t_internal {
|
||
|
uint32_t hashTable[LZ4_HASH_SIZE_U32];
|
||
|
uint32_t currentOffset;
|
||
|
uint16_t initCheck;
|
||
|
uint16_t tableType;
|
||
|
const uint8_t* dictionary;
|
||
|
const LZ4_stream_t_internal* dictCtx;
|
||
|
uint32_t dictSize;
|
||
|
};
|
||
|
|
||
|
typedef struct {
|
||
|
const uint8_t* externalDict;
|
||
|
size_t extDictSize;
|
||
|
const uint8_t* prefixEnd;
|
||
|
size_t prefixSize;
|
||
|
} LZ4_streamDecode_t_internal;
|
||
|
|
||
|
#else
|
||
|
|
||
|
typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
|
||
|
struct LZ4_stream_t_internal {
|
||
|
unsigned int hashTable[LZ4_HASH_SIZE_U32];
|
||
|
unsigned int currentOffset;
|
||
|
unsigned short initCheck;
|
||
|
unsigned short tableType;
|
||
|
const unsigned char* dictionary;
|
||
|
const LZ4_stream_t_internal* dictCtx;
|
||
|
unsigned int dictSize;
|
||
|
};
|
||
|
|
||
|
typedef struct {
|
||
|
const unsigned char* externalDict;
|
||
|
size_t extDictSize;
|
||
|
const unsigned char* prefixEnd;
|
||
|
size_t prefixSize;
|
||
|
} LZ4_streamDecode_t_internal;
|
||
|
|
||
|
#endif
|
||
|
|
||
|
/*!
|
||
|
* LZ4_stream_t :
|
||
|
* information structure to track an LZ4 stream.
|
||
|
* init this structure before first use.
|
||
|
* note : only use in association with static linking !
|
||
|
* this definition is not API/ABI safe,
|
||
|
* it may change in a future version !
|
||
|
*/
|
||
|
#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE-3)) + 4)
|
||
|
#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U64 * sizeof(unsigned long long))
|
||
|
union LZ4_stream_u {
|
||
|
unsigned long long table[LZ4_STREAMSIZE_U64];
|
||
|
LZ4_stream_t_internal internal_donotuse;
|
||
|
} ; /* previously typedef'd to LZ4_stream_t */
|
||
|
|
||
|
|
||
|
/*!
|
||
|
* LZ4_streamDecode_t :
|
||
|
* information structure to track an LZ4 stream during decompression.
|
||
|
* init this structure using LZ4_setStreamDecode (or memset()) before first use
|
||
|
* note : only use in association with static linking !
|
||
|
* this definition is not API/ABI safe,
|
||
|
* and may change in a future version !
|
||
|
*/
|
||
|
#define LZ4_STREAMDECODESIZE_U64 4
|
||
|
#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned long long))
|
||
|
union LZ4_streamDecode_u {
|
||
|
unsigned long long table[LZ4_STREAMDECODESIZE_U64];
|
||
|
LZ4_streamDecode_t_internal internal_donotuse;
|
||
|
} ; /* previously typedef'd to LZ4_streamDecode_t */
|
||
|
|
||
|
|
||
|
/*-************************************
|
||
|
* Obsolete Functions
|
||
|
**************************************/
|
||
|
|
||
|
/*! Deprecation warnings
|
||
|
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.
|
||
|
Otherwise, it's also possible to define LZ4_DISABLE_DEPRECATE_WARNINGS */
|
||
|
#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS
|
||
|
# define LZ4_DEPRECATED(message) /* disable deprecation warnings */
|
||
|
#else
|
||
|
# define LZ4_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
|
||
|
# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
|
||
|
# define LZ4_DEPRECATED(message) [[deprecated(message)]]
|
||
|
# elif (LZ4_GCC_VERSION >= 405) || defined(__clang__)
|
||
|
# define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
|
||
|
# elif (LZ4_GCC_VERSION >= 301)
|
||
|
# define LZ4_DEPRECATED(message) __attribute__((deprecated))
|
||
|
# elif defined(_MSC_VER)
|
||
|
# define LZ4_DEPRECATED(message) __declspec(deprecated(message))
|
||
|
# else
|
||
|
# pragma message("WARNING: You need to implement LZ4_DEPRECATED for this compiler")
|
||
|
# define LZ4_DEPRECATED(message)
|
||
|
# endif
|
||
|
#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */
|
||
|
|
||
|
/* Obsolete compression functions */
|
||
|
LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress (const char* source, char* dest, int sourceSize);
|
||
|
LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* source, char* dest, int sourceSize, 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 */
|
||
|
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; 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 */
|
||
|
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);
|
||
|
|
||
|
#endif /* LZ4_H_2983827168210 */
|
||
|
|
||
|
|
||
|
#if defined (__cplusplus)
|
||
|
}
|
||
|
#endif
|