228 lines
12 KiB
C
228 lines
12 KiB
C
/*
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LZ4 HC - High Compression Mode of LZ4
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Header File
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Copyright (C) 2011-2016, 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 source repository : https://github.com/lz4/lz4
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- LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
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*/
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#ifndef LZ4_HC_H_19834876238432
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#define LZ4_HC_H_19834876238432
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#if defined (__cplusplus)
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extern "C" {
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#endif
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/* --- Dependency --- */
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/* note : lz4hc is not an independent module, it requires lz4.h/lz4.c for proper compilation */
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#include "lz4.h" /* stddef, LZ4LIB_API, LZ4_DEPRECATED */
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/* --- Useful constants --- */
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#define LZ4HC_MIN_CLEVEL 3
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#define LZ4HC_DEFAULT_CLEVEL 9
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#define LZ4HC_MAX_CLEVEL 12
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/*-************************************
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* Block Compression
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**************************************/
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/*! LZ4_compress_HC() :
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* Compress data from `src` into `dst`, using the more powerful but slower "HC" algorithm.
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* `dst` must be already allocated.
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* Compression is guaranteed to succeed if `dstCapacity >= LZ4_compressBound(srcSize)` (see "lz4.h")
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* Max supported `srcSize` value is LZ4_MAX_INPUT_SIZE (see "lz4.h")
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* `compressionLevel` : Recommended values are between 4 and 9, although any value between 1 and LZ4HC_MAX_CLEVEL will work.
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* Values >LZ4HC_MAX_CLEVEL behave the same as LZ4HC_MAX_CLEVEL.
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* @return : the number of bytes written into 'dst'
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* or 0 if compression fails.
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*/
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LZ4LIB_API int LZ4_compress_HC (const char* src, char* dst, int srcSize, int dstCapacity, int compressionLevel);
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/* Note :
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* Decompression functions are provided within "lz4.h" (BSD license)
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*/
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/*! LZ4_compress_HC_extStateHC() :
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* Same as LZ4_compress_HC(), but using an externally allocated memory segment for `state`.
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* `state` size is provided by LZ4_sizeofStateHC().
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* Memory segment must be aligned on 8-bytes boundaries (which a normal malloc() will do properly).
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*/
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LZ4LIB_API int LZ4_compress_HC_extStateHC(void* state, const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel);
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LZ4LIB_API int LZ4_sizeofStateHC(void);
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/*-************************************
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* Streaming Compression
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* Bufferless synchronous API
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**************************************/
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typedef union LZ4_streamHC_u LZ4_streamHC_t; /* incomplete type (defined later) */
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/*! LZ4_createStreamHC() and LZ4_freeStreamHC() :
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* These functions create and release memory for LZ4 HC streaming state.
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* Newly created states are automatically initialized.
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* Existing states can be re-used several times, using LZ4_resetStreamHC().
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* These methods are API and ABI stable, they can be used in combination with a DLL.
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*/
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LZ4LIB_API LZ4_streamHC_t* LZ4_createStreamHC(void);
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LZ4LIB_API int LZ4_freeStreamHC (LZ4_streamHC_t* streamHCPtr);
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LZ4LIB_API void LZ4_resetStreamHC (LZ4_streamHC_t* streamHCPtr, int compressionLevel);
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LZ4LIB_API int LZ4_loadDictHC (LZ4_streamHC_t* streamHCPtr, const char* dictionary, int dictSize);
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LZ4LIB_API int LZ4_compress_HC_continue (LZ4_streamHC_t* streamHCPtr, const char* src, char* dst, int srcSize, int maxDstSize);
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LZ4LIB_API int LZ4_saveDictHC (LZ4_streamHC_t* streamHCPtr, char* safeBuffer, int maxDictSize);
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/*
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These functions compress data in successive blocks of any size, using previous blocks as dictionary.
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One key assumption is that previous blocks (up to 64 KB) remain read-accessible while compressing next blocks.
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There is an exception for ring buffers, which can be smaller than 64 KB.
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Ring buffers scenario is automatically detected and handled by LZ4_compress_HC_continue().
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Before starting compression, state must be properly initialized, using LZ4_resetStreamHC().
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A first "fictional block" can then be designated as initial dictionary, using LZ4_loadDictHC() (Optional).
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Then, use LZ4_compress_HC_continue() to compress each successive block.
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Previous memory blocks (including initial dictionary when present) must remain accessible and unmodified during compression.
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'dst' buffer should be sized to handle worst case scenarios, using LZ4_compressBound(), to ensure operation success.
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If, for any reason, previous data blocks can't be preserved unmodified in memory during next compression block,
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you must save it to a safer memory space, using LZ4_saveDictHC().
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Return value of LZ4_saveDictHC() is the size of dictionary effectively saved into 'safeBuffer'.
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*/
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/*-******************************************
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* !!!!! STATIC LINKING ONLY !!!!!
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*******************************************/
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/*-*************************************
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* PRIVATE DEFINITIONS :
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* Do not use these definitions.
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* They are exposed to allow static allocation of `LZ4_streamHC_t`.
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* Using these definitions makes the code vulnerable to potential API break when upgrading LZ4
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**************************************/
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#define LZ4HC_DICTIONARY_LOGSIZE 16
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#define LZ4HC_MAXD (1<<(LZ4HC_DICTIONARY_LOGSIZE+1))
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#define LZ4HC_MAXD_MASK (LZ4HC_MAXD - 1)
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#define LZ4HC_HASH_LOG (LZ4HC_DICTIONARY_LOGSIZE+2)
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#define LZ4HC_HASHTABLESIZE (1 << LZ4HC_HASH_LOG)
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#define LZ4HC_HASH_MASK (LZ4HC_HASHTABLESIZE - 1)
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#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
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#include <stdint.h>
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typedef struct
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{
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uint32_t hashTable[LZ4HC_HASHTABLESIZE];
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uint16_t chainTable[LZ4HC_MAXD];
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const uint8_t* end; /* next block here to continue on current prefix */
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const uint8_t* base; /* All index relative to this position */
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const uint8_t* dictBase; /* alternate base for extDict */
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uint8_t* inputBuffer; /* deprecated */
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uint32_t dictLimit; /* below that point, need extDict */
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uint32_t lowLimit; /* below that point, no more dict */
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uint32_t nextToUpdate; /* index from which to continue dictionary update */
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uint32_t searchNum; /* only for optimal parser */
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uint32_t compressionLevel;
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} LZ4HC_CCtx_internal;
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#else
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typedef struct
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{
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unsigned int hashTable[LZ4HC_HASHTABLESIZE];
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unsigned short chainTable[LZ4HC_MAXD];
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const unsigned char* end; /* next block here to continue on current prefix */
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const unsigned char* base; /* All index relative to this position */
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const unsigned char* dictBase; /* alternate base for extDict */
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unsigned char* inputBuffer; /* deprecated */
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unsigned int dictLimit; /* below that point, need extDict */
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unsigned int lowLimit; /* below that point, no more dict */
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unsigned int nextToUpdate; /* index from which to continue dictionary update */
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unsigned int searchNum; /* only for optimal parser */
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unsigned int compressionLevel;
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} LZ4HC_CCtx_internal;
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#endif
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#define LZ4_STREAMHCSIZE 4*LZ4HC_HASHTABLESIZE + 2*LZ4HC_MAXD + 52 /* 393268 */
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#define LZ4_STREAMHCSIZE_SIZET (LZ4_STREAMHCSIZE / sizeof(size_t))
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union LZ4_streamHC_u {
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size_t table[LZ4_STREAMHCSIZE_SIZET];
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LZ4HC_CCtx_internal internal_donotuse;
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}; /* previously typedef'd to LZ4_streamHC_t */
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/*
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LZ4_streamHC_t :
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This structure allows static allocation of LZ4 HC streaming state.
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State must be initialized using LZ4_resetStreamHC() before first use.
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Static allocation shall only be used in combination with static linking.
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When invoking LZ4 from a DLL, use create/free functions instead, which are API and ABI stable.
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*/
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/*-************************************
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* Deprecated Functions
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**************************************/
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/* see lz4.h LZ4_DISABLE_DEPRECATE_WARNINGS to turn off deprecation warnings */
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/* deprecated compression functions */
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/* these functions will trigger warning messages in future releases */
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LZ4_DEPRECATED("use LZ4_compress_HC() instead") int LZ4_compressHC (const char* source, char* dest, int inputSize);
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LZ4_DEPRECATED("use LZ4_compress_HC() instead") int LZ4_compressHC_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
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LZ4_DEPRECATED("use LZ4_compress_HC() instead") int LZ4_compressHC2 (const char* source, char* dest, int inputSize, int compressionLevel);
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LZ4_DEPRECATED("use LZ4_compress_HC() instead") int LZ4_compressHC2_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
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LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") int LZ4_compressHC_withStateHC (void* state, const char* source, char* dest, int inputSize);
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LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
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LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") int LZ4_compressHC2_withStateHC (void* state, const char* source, char* dest, int inputSize, int compressionLevel);
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LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") int LZ4_compressHC2_limitedOutput_withStateHC(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
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LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") int LZ4_compressHC_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize);
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LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") int LZ4_compressHC_limitedOutput_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
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/* Deprecated Streaming functions using older model; should no longer be used */
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LZ4_DEPRECATED("use LZ4_createStreamHC() instead") void* LZ4_createHC (char* inputBuffer);
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LZ4_DEPRECATED("use LZ4_saveDictHC() instead") char* LZ4_slideInputBufferHC (void* LZ4HC_Data);
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LZ4_DEPRECATED("use LZ4_freeStreamHC() instead") int LZ4_freeHC (void* LZ4HC_Data);
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LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel);
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LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
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LZ4_DEPRECATED("use LZ4_createStreamHC() instead") int LZ4_sizeofStreamStateHC(void);
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LZ4_DEPRECATED("use LZ4_resetStreamHC() instead") int LZ4_resetStreamStateHC(void* state, char* inputBuffer);
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#if defined (__cplusplus)
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}
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#endif
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#endif /* LZ4_HC_H_19834876238432 */
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