lz4frame.h

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/*
   LZ4 auto-framing library
   Header File
   Copyright (C) 2011-2017, Yann Collet.
   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions are
   met:

       * Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
       * Redistributions in binary form must reproduce the above
   copyright notice, this list of conditions and the following disclaimer
   in the documentation and/or other materials provided with the
   distribution.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

   You can contact the author at :
   - LZ4 source repository : https://github.com/lz4/lz4
   - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
*/

/* LZ4F is a stand-alone API to create LZ4-compressed frames
 * conformant with specification v1.5.1.
 * It also offers streaming capabilities.
 * lz4.h is not required when using lz4frame.h.
 * */

#ifndef LZ4F_H_09782039843
#define LZ4F_H_09782039843

#if defined (__cplusplus)
extern "C" {
#endif

/* ---   Dependency   --- */
#include <stddef.h>   /* size_t */


/*-***************************************************************
 *  Compiler specifics
 *****************************************************************/
/*  LZ4_DLL_EXPORT :
 *  Enable exporting of functions when building a Windows DLL
 *  LZ4FLIB_API :
 *  Control library symbols visibility.
 */
#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1)
#  define LZ4FLIB_API __declspec(dllexport)
#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1)
#  define LZ4FLIB_API __declspec(dllimport)
#elif defined(__GNUC__) && (__GNUC__ >= 4)
#  define LZ4FLIB_API __attribute__ ((__visibility__ ("default")))
#else
#  define LZ4FLIB_API
#endif

#ifdef LZ4F_DISABLE_DEPRECATE_WARNINGS
#  define LZ4F_DEPRECATE(x) x
#else
#  if defined(_MSC_VER)
#    define LZ4F_DEPRECATE(x) x   /* __declspec(deprecated) x - only works with C++ */
#  elif defined(__clang__) || (defined(__GNUC__) && (__GNUC__ >= 6))
#    define LZ4F_DEPRECATE(x) x __attribute__((deprecated))
#  else
#    define LZ4F_DEPRECATE(x) x   /* no deprecation warning for this compiler */
#  endif
#endif


/*-************************************
 *  Error management
 **************************************/
typedef size_t LZ4F_errorCode_t;

LZ4FLIB_API unsigned    LZ4F_isError(LZ4F_errorCode_t code);   
LZ4FLIB_API const char* LZ4F_getErrorName(LZ4F_errorCode_t code);   
/*-************************************
 *  Frame compression types
 **************************************/
/* #define LZ4F_DISABLE_OBSOLETE_ENUMS */  /* uncomment to disable obsolete enums */
#ifndef LZ4F_DISABLE_OBSOLETE_ENUMS
#  define LZ4F_OBSOLETE_ENUM(x) , LZ4F_DEPRECATE(x) = LZ4F_##x
#else
#  define LZ4F_OBSOLETE_ENUM(x)
#endif

/* The larger the block size, the (slightly) better the compression ratio,
 * though there are diminishing returns.
 * Larger blocks also increase memory usage on both compression and decompression sides. */
typedef enum {
    LZ4F_default=0,
    LZ4F_max64KB=4,
    LZ4F_max256KB=5,
    LZ4F_max1MB=6,
    LZ4F_max4MB=7
    LZ4F_OBSOLETE_ENUM(max64KB)
    LZ4F_OBSOLETE_ENUM(max256KB)
    LZ4F_OBSOLETE_ENUM(max1MB)
    LZ4F_OBSOLETE_ENUM(max4MB)
} LZ4F_blockSizeID_t;

/* Linked blocks sharply reduce inefficiencies when using small blocks,
 * they compress better.
 * However, some LZ4 decoders are only compatible with independent blocks */
typedef enum {
    LZ4F_blockLinked=0,
    LZ4F_blockIndependent
    LZ4F_OBSOLETE_ENUM(blockLinked)
    LZ4F_OBSOLETE_ENUM(blockIndependent)
} LZ4F_blockMode_t;

typedef enum {
    LZ4F_noContentChecksum=0,
    LZ4F_contentChecksumEnabled
    LZ4F_OBSOLETE_ENUM(noContentChecksum)
    LZ4F_OBSOLETE_ENUM(contentChecksumEnabled)
} LZ4F_contentChecksum_t;

typedef enum {
    LZ4F_frame=0,
    LZ4F_skippableFrame
    LZ4F_OBSOLETE_ENUM(skippableFrame)
} LZ4F_frameType_t;

#ifndef LZ4F_DISABLE_OBSOLETE_ENUMS
typedef LZ4F_blockSizeID_t blockSizeID_t;
typedef LZ4F_blockMode_t blockMode_t;
typedef LZ4F_frameType_t frameType_t;
typedef LZ4F_contentChecksum_t contentChecksum_t;
#endif

typedef struct {
  LZ4F_blockSizeID_t     blockSizeID;           /* max64KB, max256KB, max1MB, max4MB ; 0 == default */
  LZ4F_blockMode_t       blockMode;             /* blockLinked, blockIndependent ; 0 == default */
  LZ4F_contentChecksum_t contentChecksumFlag;   /* noContentChecksum, contentChecksumEnabled ; 0 == default  */
  LZ4F_frameType_t       frameType;             /* LZ4F_frame, skippableFrame ; 0 == default */
  unsigned long long     contentSize;           /* Size of uncompressed (original) content ; 0 == unknown */
  unsigned               reserved[2];           /* must be zero for forward compatibility */
} LZ4F_frameInfo_t;

typedef struct {
  LZ4F_frameInfo_t frameInfo;
  int      compressionLevel;       /* 0 == default (fast mode); values above LZ4HC_CLEVEL_MAX count as LZ4HC_CLEVEL_MAX; values below 0 trigger "fast acceleration", proportional to value */
  unsigned autoFlush;              /* 1 == always flush (reduce usage of tmp buffer) */
  unsigned reserved[4];            /* must be zero for forward compatibility */
} LZ4F_preferences_t;


/*-*********************************
*  Simple compression function
***********************************/
LZ4FLIB_API size_t LZ4F_compressFrameBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr);

LZ4FLIB_API size_t LZ4F_compressFrame(void* dstBuffer, size_t dstCapacity, const void* srcBuffer, size_t srcSize, const LZ4F_preferences_t* preferencesPtr);



/*-***********************************
*  Advanced compression functions
*************************************/
typedef struct LZ4F_cctx_s LZ4F_cctx;   /* incomplete type */
typedef LZ4F_cctx* LZ4F_compressionContext_t;   /* for compatibility with previous API version */

typedef struct {
  unsigned stableSrc;    /* 1 == src content will remain present on future calls to LZ4F_compress(); skip copying src content within tmp buffer */
  unsigned reserved[3];
} LZ4F_compressOptions_t;

/*---   Resource Management   ---*/

#define LZ4F_VERSION 100
LZ4FLIB_API unsigned LZ4F_getVersion(void);
LZ4FLIB_API LZ4F_errorCode_t LZ4F_createCompressionContext(LZ4F_cctx** cctxPtr, unsigned version);
LZ4FLIB_API LZ4F_errorCode_t LZ4F_freeCompressionContext(LZ4F_cctx* cctx);


/*----    Compression    ----*/

#define LZ4F_HEADER_SIZE_MAX 15

LZ4FLIB_API size_t LZ4F_compressBegin(LZ4F_cctx* cctx, void* dstBuffer, size_t dstCapacity, const LZ4F_preferences_t* prefsPtr);

LZ4FLIB_API size_t LZ4F_compressBound(size_t srcSize, const LZ4F_preferences_t* prefsPtr);

LZ4FLIB_API size_t LZ4F_compressUpdate(LZ4F_cctx* cctx, void* dstBuffer, size_t dstCapacity, const void* srcBuffer, size_t srcSize, const LZ4F_compressOptions_t* cOptPtr);

LZ4FLIB_API size_t LZ4F_flush(LZ4F_cctx* cctx, void* dstBuffer, size_t dstCapacity, const LZ4F_compressOptions_t* cOptPtr);

LZ4FLIB_API size_t LZ4F_compressEnd(LZ4F_cctx* cctx, void* dstBuffer, size_t dstCapacity, const LZ4F_compressOptions_t* cOptPtr);


/*-*********************************
*  Decompression functions
***********************************/
typedef struct LZ4F_dctx_s LZ4F_dctx;   /* incomplete type */
typedef LZ4F_dctx* LZ4F_decompressionContext_t;   /* compatibility with previous API versions */

typedef struct {
  unsigned stableDst;    /* pledge that at least 64KB+64Bytes of previously decompressed data remain unmodifed where it was decoded. This optimization skips storage operations in tmp buffers */
  unsigned reserved[3];
} LZ4F_decompressOptions_t;


/* Resource management */

LZ4FLIB_API LZ4F_errorCode_t LZ4F_createDecompressionContext(LZ4F_dctx** dctxPtr, unsigned version);
LZ4FLIB_API LZ4F_errorCode_t LZ4F_freeDecompressionContext(LZ4F_dctx* dctx);


/*-***********************************
*  Streaming decompression functions
*************************************/

LZ4FLIB_API size_t LZ4F_getFrameInfo(LZ4F_dctx* dctx,
                                     LZ4F_frameInfo_t* frameInfoPtr,
                                     const void* srcBuffer, size_t* srcSizePtr);

LZ4FLIB_API size_t LZ4F_decompress(LZ4F_dctx* dctx,
                                   void* dstBuffer, size_t* dstSizePtr,
                                   const void* srcBuffer, size_t* srcSizePtr,
                                   const LZ4F_decompressOptions_t* dOptPtr);


LZ4FLIB_API void LZ4F_resetDecompressionContext(LZ4F_dctx* dctx);   /* always successful */



#if defined (__cplusplus)
}
#endif

#endif  /* LZ4F_H_09782039843 */