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 able to create and decode LZ4 frames
 * conformant with specification v1.6.1 in doc/lz4_Frame_format.md .
 * Generated frames are compatible with `lz4` CLI.
 *
 * LZ4F also offers streaming capabilities.
 *
 * lz4.h is not required when using lz4frame.h,
 * except to extract common constant such as LZ4_VERSION_NUMBER.
 * */

#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_VISIBILITY :
 *  Control library symbols visibility.
 */
#ifndef LZ4FLIB_VISIBILITY
#  if defined(__GNUC__) && (__GNUC__ >= 4)
#    define LZ4FLIB_VISIBILITY __attribute__ ((visibility ("default")))
#  else
#    define LZ4FLIB_VISIBILITY
#  endif
#endif
#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1)
#  define LZ4FLIB_API __declspec(dllexport) LZ4FLIB_VISIBILITY
#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1)
#  define LZ4FLIB_API __declspec(dllimport) LZ4FLIB_VISIBILITY
#else
#  define LZ4FLIB_API LZ4FLIB_VISIBILITY
#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_ENABLE_OBSOLETE_ENUMS   // uncomment to enable obsolete enums */
#ifdef LZ4F_ENABLE_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_noBlockChecksum=0,
    LZ4F_blockChecksumEnabled
} LZ4F_blockChecksum_t;

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

#ifdef LZ4F_ENABLE_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;           /* LZ4F_blockLinked, LZ4F_blockIndependent; 0 == default */
  LZ4F_contentChecksum_t contentChecksumFlag; /* 1: frame terminated with 32-bit checksum of decompressed data; 0: disabled (default) */
  LZ4F_frameType_t       frameType;           /* read-only field : LZ4F_frame or LZ4F_skippableFrame */
  unsigned long long     contentSize;         /* Size of uncompressed content ; 0 == unknown */
  unsigned               dictID;              /* Dictionary ID, sent by compressor to help decoder select correct dictionary; 0 == no dictID provided */
  LZ4F_blockChecksum_t   blockChecksumFlag;   /* 1: each block followed by a checksum of block's compressed data; 0: disabled (default) */
} LZ4F_frameInfo_t;

#define LZ4F_INIT_FRAMEINFO   { LZ4F_default, LZ4F_blockLinked, LZ4F_noContentChecksum, LZ4F_frame, 0ULL, 0U, LZ4F_noBlockChecksum }    /* v1.8.3+ */

typedef struct {
  LZ4F_frameInfo_t frameInfo;
  int      compressionLevel;    /* 0: default (fast mode); values > LZ4HC_CLEVEL_MAX count as LZ4HC_CLEVEL_MAX; values < 0 trigger "fast acceleration" */
  unsigned autoFlush;           /* 1: always flush; reduces usage of internal buffers */
  unsigned favorDecSpeed;       /* 1: parser favors decompression speed vs compression ratio. Only works for high compression modes (>= LZ4HC_CLEVEL_OPT_MIN) */  /* v1.8.2+ */
  unsigned reserved[3];         /* must be zero for forward compatibility */
} LZ4F_preferences_t;

#define LZ4F_INIT_PREFERENCES   { LZ4F_INIT_FRAMEINFO, 0, 0u, 0u, { 0u, 0u, 0u } }    /* v1.8.3+ */


/*-*********************************
*  Simple compression function
***********************************/

LZ4FLIB_API int LZ4F_compressionLevel_max(void);   /* v1.8.0+ */

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    /* This number can be used to check for an incompatible API breaking change */
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_MIN  7   /* LZ4 Frame header size can vary, depending on selected paramaters */
#define LZ4F_HEADER_SIZE_MAX 19

/* Size in bytes of a block header in little-endian format. Highest bit indicates if block data is uncompressed */
#define LZ4F_BLOCK_HEADER_SIZE 4

/* Size in bytes of a block checksum footer in little-endian format. */
#define LZ4F_BLOCK_CHECKSUM_SIZE 4

/* Size in bytes of the content checksum. */
#define LZ4F_CONTENT_CHECKSUM_SIZE 4

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;    /* pledges that last 64KB decompressed data will remain available unmodified. This optimization skips storage operations in tmp buffers. */
  unsigned reserved[3];  /* must be set to zero for forward compatibility */
} 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
*************************************/

#define LZ4F_MIN_SIZE_TO_KNOW_HEADER_LENGTH 5

LZ4FLIB_API size_t LZ4F_headerSize(const void* src, size_t srcSize);

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 */

#if defined(LZ4F_STATIC_LINKING_ONLY) && !defined(LZ4F_H_STATIC_09782039843)
#define LZ4F_H_STATIC_09782039843

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

/* These declarations are not stable and may change in the future.
 * They are therefore only safe to depend on
 * when the caller is statically linked against the library.
 * To access their declarations, define LZ4F_STATIC_LINKING_ONLY.
 *
 * By default, these symbols aren't published into shared/dynamic libraries.
 * You can override this behavior and force them to be published
 * by defining LZ4F_PUBLISH_STATIC_FUNCTIONS.
 * Use at your own risk.
 */
#ifdef LZ4F_PUBLISH_STATIC_FUNCTIONS
# define LZ4FLIB_STATIC_API LZ4FLIB_API
#else
# define LZ4FLIB_STATIC_API
#endif


/* ---   Error List   --- */
#define LZ4F_LIST_ERRORS(ITEM) \
        ITEM(OK_NoError) \
        ITEM(ERROR_GENERIC) \
        ITEM(ERROR_maxBlockSize_invalid) \
        ITEM(ERROR_blockMode_invalid) \
        ITEM(ERROR_contentChecksumFlag_invalid) \
        ITEM(ERROR_compressionLevel_invalid) \
        ITEM(ERROR_headerVersion_wrong) \
        ITEM(ERROR_blockChecksum_invalid) \
        ITEM(ERROR_reservedFlag_set) \
        ITEM(ERROR_allocation_failed) \
        ITEM(ERROR_srcSize_tooLarge) \
        ITEM(ERROR_dstMaxSize_tooSmall) \
        ITEM(ERROR_frameHeader_incomplete) \
        ITEM(ERROR_frameType_unknown) \
        ITEM(ERROR_frameSize_wrong) \
        ITEM(ERROR_srcPtr_wrong) \
        ITEM(ERROR_decompressionFailed) \
        ITEM(ERROR_headerChecksum_invalid) \
        ITEM(ERROR_contentChecksum_invalid) \
        ITEM(ERROR_frameDecoding_alreadyStarted) \
        ITEM(ERROR_maxCode)

#define LZ4F_GENERATE_ENUM(ENUM) LZ4F_##ENUM,

/* enum list is exposed, to handle specific errors */
typedef enum { LZ4F_LIST_ERRORS(LZ4F_GENERATE_ENUM)
              _LZ4F_dummy_error_enum_for_c89_never_used } LZ4F_errorCodes;

LZ4FLIB_STATIC_API LZ4F_errorCodes LZ4F_getErrorCode(size_t functionResult);

LZ4FLIB_STATIC_API size_t LZ4F_getBlockSize(unsigned);

/**********************************
 *  Bulk processing dictionary API
 *********************************/

/* A Dictionary is useful for the compression of small messages (KB range).
 * It dramatically improves compression efficiency.
 *
 * LZ4 can ingest any input as dictionary, though only the last 64 KB are useful.
 * Best results are generally achieved by using Zstandard's Dictionary Builder
 * to generate a high-quality dictionary from a set of samples.
 *
 * Loading a dictionary has a cost, since it involves construction of tables.
 * The Bulk processing dictionary API makes it possible to share this cost
 * over an arbitrary number of compression jobs, even concurrently,
 * markedly improving compression latency for these cases.
 *
 * The same dictionary will have to be used on the decompression side
 * for decoding to be successful.
 * To help identify the correct dictionary at decoding stage,
 * the frame header allows optional embedding of a dictID field.
 */
typedef struct LZ4F_CDict_s LZ4F_CDict;

LZ4FLIB_STATIC_API LZ4F_CDict* LZ4F_createCDict(const void* dictBuffer, size_t dictSize);
LZ4FLIB_STATIC_API void        LZ4F_freeCDict(LZ4F_CDict* CDict);


LZ4FLIB_STATIC_API size_t LZ4F_compressFrame_usingCDict(
    LZ4F_cctx* cctx,
    void* dst, size_t dstCapacity,
    const void* src, size_t srcSize,
    const LZ4F_CDict* cdict,
    const LZ4F_preferences_t* preferencesPtr);


LZ4FLIB_STATIC_API size_t LZ4F_compressBegin_usingCDict(
    LZ4F_cctx* cctx,
    void* dstBuffer, size_t dstCapacity,
    const LZ4F_CDict* cdict,
    const LZ4F_preferences_t* prefsPtr);


LZ4FLIB_STATIC_API size_t LZ4F_decompress_usingDict(
    LZ4F_dctx* dctxPtr,
    void* dstBuffer, size_t* dstSizePtr,
    const void* srcBuffer, size_t* srcSizePtr,
    const void* dict, size_t dictSize,
    const LZ4F_decompressOptions_t* decompressOptionsPtr);

#if defined (__cplusplus)
}
#endif

#endif  /* defined(LZ4F_STATIC_LINKING_ONLY) && !defined(LZ4F_H_STATIC_09782039843) */