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607 lines
30 KiB
607 lines
30 KiB
/* |
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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 source 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 optionally 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, |
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* save the last 64KB of decoded data into a safe buffer where it can't be modified during decompression, |
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* then indicate where this data is saved using LZ4_setStreamDecode(), before decompressing next block. |
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*/ |
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LZ4LIB_API int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int srcSize, int dstCapacity); |
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LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize); |
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/*! LZ4_decompress_*_usingDict() : |
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* These decoding functions work the same as |
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* a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue() |
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* They are stand-alone, and don't need an LZ4_streamDecode_t structure. |
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* Dictionary is presumed stable : it must remain accessible and unmodified during next decompression. |
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*/ |
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LZ4LIB_API int LZ4_decompress_safe_usingDict (const char* src, char* dst, int srcSize, int dstCapcity, const char* dictStart, int dictSize); |
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LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize); |
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/*^********************************************** |
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* !!!!!! STATIC LINKING ONLY !!!!!! |
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***********************************************/ |
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/*-************************************ |
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* Unstable declarations |
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************************************** |
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* Declarations in this section should be considered unstable. |
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* Use at your own peril, etc., etc. |
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* They may be removed in the future. |
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* Their signatures may change. |
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**************************************/ |
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#ifdef LZ4_STATIC_LINKING_ONLY |
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/*! LZ4_resetStream_fast() : |
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* Use this, like LZ4_resetStream(), to prepare a context for a new chain of |
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* calls to a streaming API (e.g., LZ4_compress_fast_continue()). |
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* |
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* Note: |
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* Using this in advance of a non- streaming-compression function is redundant, |
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* and potentially bad for performance, since they all perform their own custom |
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* reset internally. |
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* |
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* Differences from LZ4_resetStream(): |
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* When an LZ4_stream_t is known to be in a internally coherent state, |
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* it can often be prepared for a new compression with almost no work, only |
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* sometimes falling back to the full, expensive reset that is always required |
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* when the stream is in an indeterminate state (i.e., the reset performed by |
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* LZ4_resetStream()). |
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* |
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* LZ4_streams are guaranteed to be in a valid state when: |
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* - returned from LZ4_createStream() |
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* - reset by LZ4_resetStream() |
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* - memset(stream, 0, sizeof(LZ4_stream_t)), though this is discouraged |
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* - the stream was in a valid state and was reset by LZ4_resetStream_fast() |
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* - the stream was in a valid state and was then used in any compression call |
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* that returned success |
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* - the stream was in an indeterminate state and was used in a compression |
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* call that fully reset the state (e.g., LZ4_compress_fast_extState()) and |
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* that returned success |
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* |
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* When a stream isn't known to be in a valid state, it is not safe to pass to |
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* any fastReset or streaming function. It must first be cleansed by the full |
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* LZ4_resetStream(). |
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*/ |
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LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr); |
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/*! LZ4_compress_fast_extState_fastReset() : |
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* A variant of LZ4_compress_fast_extState(). |
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* |
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* Using this variant avoids an expensive initialization step. It is only safe |
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* to call if the state buffer is known to be correctly initialized already |
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* (see above comment on LZ4_resetStream_fast() for a definition of "correctly |
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* initialized"). From a high level, the difference is that this function |
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* initializes the provided state with a call to something like |
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* LZ4_resetStream_fast() while LZ4_compress_fast_extState() starts with a |
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* call to LZ4_resetStream(). |
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*/ |
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LZ4LIB_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); |
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/*! LZ4_attach_dictionary() : |
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* This is an experimental API that allows for the efficient use of a |
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* static dictionary many times. |
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* |
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* Rather than re-loading the dictionary buffer into a working context before |
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* each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a |
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* working LZ4_stream_t, this function introduces a no-copy setup mechanism, |
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* in which the working stream references the dictionary stream in-place. |
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* |
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* Several assumptions are made about the state of the dictionary stream. |
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* 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
|
|
|