zstd.h

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/*
 * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under both the BSD-style license (found in the
 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
 * in the COPYING file in the root directory of this source tree).
 * You may select, at your option, one of the above-listed licenses.
 */
#if defined (__cplusplus)
extern "C" {
#endif

#ifndef ZSTD_H_235446
#define ZSTD_H_235446

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


/* =====   ZSTDLIB_API : control library symbols visibility   ===== */
#ifndef ZSTDLIB_VISIBILITY
#  if defined(__GNUC__) && (__GNUC__ >= 4)
#    define ZSTDLIB_VISIBILITY __attribute__ ((visibility ("default")))
#  else
#    define ZSTDLIB_VISIBILITY
#  endif
#endif
#if defined(ZSTD_DLL_EXPORT) && (ZSTD_DLL_EXPORT==1)
#  define ZSTDLIB_API __declspec(dllexport) ZSTDLIB_VISIBILITY
#elif defined(ZSTD_DLL_IMPORT) && (ZSTD_DLL_IMPORT==1)
#  define ZSTDLIB_API __declspec(dllimport) ZSTDLIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
#else
#  define ZSTDLIB_API ZSTDLIB_VISIBILITY
#endif


/*******************************************************************************
  Introduction

  zstd, short for Zstandard, is a fast lossless compression algorithm, targeting
  real-time compression scenarios at zlib-level and better compression ratios.
  The zstd compression library provides in-memory compression and decompression
  functions.

  The library supports regular compression levels from 1 up to ZSTD_maxCLevel(),
  which is currently 22. Levels >= 20, labeled `--ultra`, should be used with
  caution, as they require more memory. The library also offers negative
  compression levels, which extend the range of speed vs. ratio preferences.
  The lower the level, the faster the speed (at the cost of compression).

  Compression can be done in:
    - a single step (described as Simple API)
    - a single step, reusing a context (described as Explicit context)
    - unbounded multiple steps (described as Streaming compression)

  The compression ratio achievable on small data can be highly improved using
  a dictionary. Dictionary compression can be performed in:
    - a single step (described as Simple dictionary API)
    - a single step, reusing a dictionary (described as Bulk-processing
      dictionary API)

  Advanced experimental functions can be accessed using
  `#define ZSTD_STATIC_LINKING_ONLY` before including zstd.h.

  Advanced experimental APIs should never be used with a dynamically-linked
  library. They are not "stable"; their definitions or signatures may change in
  the future. Only static linking is allowed.
*******************************************************************************/

/*------   Version   ------*/
#define ZSTD_VERSION_MAJOR    1
#define ZSTD_VERSION_MINOR    3
#define ZSTD_VERSION_RELEASE  7

#define ZSTD_VERSION_NUMBER  (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE)
ZSTDLIB_API unsigned ZSTD_versionNumber(void);   
#define ZSTD_LIB_VERSION ZSTD_VERSION_MAJOR.ZSTD_VERSION_MINOR.ZSTD_VERSION_RELEASE
#define ZSTD_QUOTE(str) #str
#define ZSTD_EXPAND_AND_QUOTE(str) ZSTD_QUOTE(str)
#define ZSTD_VERSION_STRING ZSTD_EXPAND_AND_QUOTE(ZSTD_LIB_VERSION)
ZSTDLIB_API const char* ZSTD_versionString(void);   /* v1.3.0+ */

/***************************************
*  Default constant
***************************************/
#ifndef ZSTD_CLEVEL_DEFAULT
#  define ZSTD_CLEVEL_DEFAULT 3
#endif

/***************************************
*  Simple API
***************************************/
ZSTDLIB_API size_t ZSTD_compress( void* dst, size_t dstCapacity,
                            const void* src, size_t srcSize,
                                  int compressionLevel);

ZSTDLIB_API size_t ZSTD_decompress( void* dst, size_t dstCapacity,
                              const void* src, size_t compressedSize);

#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1)
#define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
ZSTDLIB_API unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);

ZSTDLIB_API unsigned long long ZSTD_getDecompressedSize(const void* src, size_t srcSize);


/*======  Helper functions  ======*/
#define ZSTD_COMPRESSBOUND(srcSize)   ((srcSize) + ((srcSize)>>8) + (((srcSize) < (128<<10)) ? (((128<<10) - (srcSize)) >> 11) /* margin, from 64 to 0 */ : 0))  /* this formula ensures that bound(A) + bound(B) <= bound(A+B) as long as A and B >= 128 KB */
ZSTDLIB_API size_t      ZSTD_compressBound(size_t srcSize); 
ZSTDLIB_API unsigned    ZSTD_isError(size_t code);          
ZSTDLIB_API const char* ZSTD_getErrorName(size_t code);     
ZSTDLIB_API int         ZSTD_maxCLevel(void);               
/***************************************
*  Explicit context
***************************************/
/*= Compression context
 *  When compressing many times,
 *  it is recommended to allocate a context just once, and re-use it for each successive compression operation.
 *  This will make workload friendlier for system's memory.
 *  Use one context per thread for parallel execution in multi-threaded environments. */
typedef struct ZSTD_CCtx_s ZSTD_CCtx;
ZSTDLIB_API ZSTD_CCtx* ZSTD_createCCtx(void);
ZSTDLIB_API size_t     ZSTD_freeCCtx(ZSTD_CCtx* cctx);

ZSTDLIB_API size_t ZSTD_compressCCtx(ZSTD_CCtx* ctx,
                                     void* dst, size_t dstCapacity,
                               const void* src, size_t srcSize,
                                     int compressionLevel);

/*= Decompression context
 *  When decompressing many times,
 *  it is recommended to allocate a context only once,
 *  and re-use it for each successive compression operation.
 *  This will make workload friendlier for system's memory.
 *  Use one context per thread for parallel execution. */
typedef struct ZSTD_DCtx_s ZSTD_DCtx;
ZSTDLIB_API ZSTD_DCtx* ZSTD_createDCtx(void);
ZSTDLIB_API size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);

ZSTDLIB_API size_t ZSTD_decompressDCtx(ZSTD_DCtx* ctx,
                                       void* dst, size_t dstCapacity,
                                 const void* src, size_t srcSize);


/**************************
*  Simple dictionary API
***************************/
ZSTDLIB_API size_t ZSTD_compress_usingDict(ZSTD_CCtx* ctx,
                                           void* dst, size_t dstCapacity,
                                     const void* src, size_t srcSize,
                                     const void* dict,size_t dictSize,
                                           int compressionLevel);

ZSTDLIB_API size_t ZSTD_decompress_usingDict(ZSTD_DCtx* dctx,
                                             void* dst, size_t dstCapacity,
                                       const void* src, size_t srcSize,
                                       const void* dict,size_t dictSize);


/**********************************
 *  Bulk processing dictionary API
 *********************************/
typedef struct ZSTD_CDict_s ZSTD_CDict;

ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict(const void* dictBuffer, size_t dictSize,
                                         int compressionLevel);

ZSTDLIB_API size_t      ZSTD_freeCDict(ZSTD_CDict* CDict);

ZSTDLIB_API size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
                                            void* dst, size_t dstCapacity,
                                      const void* src, size_t srcSize,
                                      const ZSTD_CDict* cdict);


typedef struct ZSTD_DDict_s ZSTD_DDict;

ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict(const void* dictBuffer, size_t dictSize);

ZSTDLIB_API size_t      ZSTD_freeDDict(ZSTD_DDict* ddict);

ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
                                              void* dst, size_t dstCapacity,
                                        const void* src, size_t srcSize,
                                        const ZSTD_DDict* ddict);


/****************************
*  Streaming
****************************/

typedef struct ZSTD_inBuffer_s {
  const void* src;    
  size_t size;        
  size_t pos;         
} ZSTD_inBuffer;

typedef struct ZSTD_outBuffer_s {
  void*  dst;         
  size_t size;        
  size_t pos;         
} ZSTD_outBuffer;



/*-***********************************************************************
*  Streaming compression - HowTo
*
*  A ZSTD_CStream object is required to track streaming operation.
*  Use ZSTD_createCStream() and ZSTD_freeCStream() to create/release resources.
*  ZSTD_CStream objects can be reused multiple times on consecutive compression operations.
*  It is recommended to re-use ZSTD_CStream in situations where many streaming operations will be achieved consecutively,
*  since it will play nicer with system's memory, by re-using already allocated memory.
*  Use one separate ZSTD_CStream per thread for parallel execution.
*
*  Start a new compression by initializing ZSTD_CStream context.
*  Use ZSTD_initCStream() to start a new compression operation.
*  Use variants ZSTD_initCStream_usingDict() or ZSTD_initCStream_usingCDict() for streaming with dictionary (experimental section)
*
*  Use ZSTD_compressStream() as many times as necessary to consume input stream.
*  The function will automatically update both `pos` fields within `input` and `output`.
*  Note that the function may not consume the entire input,
*  for example, because the output buffer is already full,
*  in which case `input.pos < input.size`.
*  The caller must check if input has been entirely consumed.
*  If not, the caller must make some room to receive more compressed data,
*  typically by emptying output buffer, or allocating a new output buffer,
*  and then present again remaining input data.
*  @return : a size hint, preferred nb of bytes to use as input for next function call
*            or an error code, which can be tested using ZSTD_isError().
*            Note 1 : it's just a hint, to help latency a little, any other value will work fine.
*            Note 2 : size hint is guaranteed to be <= ZSTD_CStreamInSize()
*
*  At any moment, it's possible to flush whatever data might remain stuck within internal buffer,
*  using ZSTD_flushStream(). `output->pos` will be updated.
*  Note that, if `output->size` is too small, a single invocation of ZSTD_flushStream() might not be enough (return code > 0).
*  In which case, make some room to receive more compressed data, and call again ZSTD_flushStream().
*  @return : 0 if internal buffers are entirely flushed,
*            >0 if some data still present within internal buffer (the value is minimal estimation of remaining size),
*            or an error code, which can be tested using ZSTD_isError().
*
*  ZSTD_endStream() instructs to finish a frame.
*  It will perform a flush and write frame epilogue.
*  The epilogue is required for decoders to consider a frame completed.
*  flush() operation is the same, and follows same rules as ZSTD_flushStream().
*  @return : 0 if frame fully completed and fully flushed,
*            >0 if some data still present within internal buffer (the value is minimal estimation of remaining size),
*            or an error code, which can be tested using ZSTD_isError().
*
* *******************************************************************/

typedef ZSTD_CCtx ZSTD_CStream;  
                                 /* Continue to distinguish them for compatibility with older versions <= v1.2.0 */
/*===== ZSTD_CStream management functions =====*/
ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream(void);
ZSTDLIB_API size_t ZSTD_freeCStream(ZSTD_CStream* zcs);

/*===== Streaming compression functions =====*/
ZSTDLIB_API size_t ZSTD_initCStream(ZSTD_CStream* zcs, int compressionLevel);
ZSTDLIB_API size_t ZSTD_compressStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output, ZSTD_inBuffer* input);
ZSTDLIB_API size_t ZSTD_flushStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output);
ZSTDLIB_API size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output);

ZSTDLIB_API size_t ZSTD_CStreamInSize(void);    
ZSTDLIB_API size_t ZSTD_CStreamOutSize(void);   
/*-***************************************************************************
*  Streaming decompression - HowTo
*
*  A ZSTD_DStream object is required to track streaming operations.
*  Use ZSTD_createDStream() and ZSTD_freeDStream() to create/release resources.
*  ZSTD_DStream objects can be re-used multiple times.
*
*  Use ZSTD_initDStream() to start a new decompression operation,
*   or ZSTD_initDStream_usingDict() if decompression requires a dictionary.
*   @return : recommended first input size
*
*  Use ZSTD_decompressStream() repetitively to consume your input.
*  The function will update both `pos` fields.
*  If `input.pos < input.size`, some input has not been consumed.
*  It's up to the caller to present again remaining data.
*  The function tries to flush all data decoded immediately, repecting buffer sizes.
*  If `output.pos < output.size`, decoder has flushed everything it could.
*  But if `output.pos == output.size`, there is no such guarantee,
*  it's likely that some decoded data was not flushed and still remains within internal buffers.
*  In which case, call ZSTD_decompressStream() again to flush whatever remains in the buffer.
*  When no additional input is provided, amount of data flushed is necessarily <= ZSTD_BLOCKSIZE_MAX.
* @return : 0 when a frame is completely decoded and fully flushed,
*        or an error code, which can be tested using ZSTD_isError(),
*        or any other value > 0, which means there is still some decoding or flushing to do to complete current frame :
*                                the return value is a suggested next input size (a hint for better latency)
*                                that will never load more than the current frame.
* *******************************************************************************/

typedef ZSTD_DCtx ZSTD_DStream;  
                                 /* For compatibility with versions <= v1.2.0, prefer differentiating them. */
/*===== ZSTD_DStream management functions =====*/
ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream(void);
ZSTDLIB_API size_t ZSTD_freeDStream(ZSTD_DStream* zds);

/*===== Streaming decompression functions =====*/
ZSTDLIB_API size_t ZSTD_initDStream(ZSTD_DStream* zds);
ZSTDLIB_API size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inBuffer* input);

ZSTDLIB_API size_t ZSTD_DStreamInSize(void);    
ZSTDLIB_API size_t ZSTD_DStreamOutSize(void);   
#endif  /* ZSTD_H_235446 */




#if defined(ZSTD_STATIC_LINKING_ONLY) && !defined(ZSTD_H_ZSTD_STATIC_LINKING_ONLY)
#define ZSTD_H_ZSTD_STATIC_LINKING_ONLY

/****************************************************************************************
 *   ADVANCED AND EXPERIMENTAL FUNCTIONS
 ****************************************************************************************
 * The definitions in this section are considered experimental.
 * They should never be used with a dynamic library, as prototypes may change in the future.
 * They are provided for advanced scenarios.
 * Use them only in association with static linking.
 * ***************************************************************************************/

ZSTDLIB_API int ZSTD_minCLevel(void);  
/* ---  Constants  ---*/
#define ZSTD_MAGICNUMBER            0xFD2FB528   /* v0.8+ */
#define ZSTD_MAGIC_DICTIONARY       0xEC30A437   /* v0.7+ */
#define ZSTD_MAGIC_SKIPPABLE_START  0x184D2A50U

#define ZSTD_BLOCKSIZELOG_MAX 17
#define ZSTD_BLOCKSIZE_MAX   (1<<ZSTD_BLOCKSIZELOG_MAX)   /* define, for static allocation */

#define ZSTD_WINDOWLOG_MAX_32   30
#define ZSTD_WINDOWLOG_MAX_64   31
#define ZSTD_WINDOWLOG_MAX    ((unsigned)(sizeof(size_t) == 4 ? ZSTD_WINDOWLOG_MAX_32 : ZSTD_WINDOWLOG_MAX_64))
#define ZSTD_WINDOWLOG_MIN      10
#define ZSTD_HASHLOG_MAX      ((ZSTD_WINDOWLOG_MAX < 30) ? ZSTD_WINDOWLOG_MAX : 30)
#define ZSTD_HASHLOG_MIN         6
#define ZSTD_CHAINLOG_MAX_32    29
#define ZSTD_CHAINLOG_MAX_64    30
#define ZSTD_CHAINLOG_MAX     ((unsigned)(sizeof(size_t) == 4 ? ZSTD_CHAINLOG_MAX_32 : ZSTD_CHAINLOG_MAX_64))
#define ZSTD_CHAINLOG_MIN       ZSTD_HASHLOG_MIN
#define ZSTD_HASHLOG3_MAX       17
#define ZSTD_SEARCHLOG_MAX     (ZSTD_WINDOWLOG_MAX-1)
#define ZSTD_SEARCHLOG_MIN       1
#define ZSTD_SEARCHLENGTH_MAX    7   /* only for ZSTD_fast, other strategies are limited to 6 */
#define ZSTD_SEARCHLENGTH_MIN    3   /* only for ZSTD_btopt, other strategies are limited to 4 */
#define ZSTD_TARGETLENGTH_MAX  ZSTD_BLOCKSIZE_MAX
#define ZSTD_TARGETLENGTH_MIN    0   /* note : comparing this constant to an unsigned results in a tautological test */
#define ZSTD_LDM_MINMATCH_MAX 4096
#define ZSTD_LDM_MINMATCH_MIN    4
#define ZSTD_LDM_BUCKETSIZELOG_MAX 8

#define ZSTD_FRAMEHEADERSIZE_PREFIX 5   /* minimum input size to know frame header size */
#define ZSTD_FRAMEHEADERSIZE_MIN    6
#define ZSTD_FRAMEHEADERSIZE_MAX   18   /* for static allocation */
static const size_t ZSTD_frameHeaderSize_prefix = ZSTD_FRAMEHEADERSIZE_PREFIX;
static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN;
static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX;
static const size_t ZSTD_skippableHeaderSize = 8;  /* magic number + skippable frame length */



/* ---  Advanced types  --- */
typedef enum { ZSTD_fast=1, ZSTD_dfast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2,
               ZSTD_btlazy2, ZSTD_btopt, ZSTD_btultra } ZSTD_strategy;   /* from faster to stronger */

typedef struct {
    unsigned windowLog;      
    unsigned chainLog;       
    unsigned hashLog;        
    unsigned searchLog;      
    unsigned searchLength;   
    unsigned targetLength;   
    ZSTD_strategy strategy;
} ZSTD_compressionParameters;

typedef struct {
    unsigned contentSizeFlag; 
    unsigned checksumFlag;    
    unsigned noDictIDFlag;    
} ZSTD_frameParameters;

typedef struct {
    ZSTD_compressionParameters cParams;
    ZSTD_frameParameters fParams;
} ZSTD_parameters;

typedef struct ZSTD_CCtx_params_s ZSTD_CCtx_params;

typedef enum {
    ZSTD_dct_auto=0,      /* dictionary is "full" when starting with ZSTD_MAGIC_DICTIONARY, otherwise it is "rawContent" */
    ZSTD_dct_rawContent,  /* ensures dictionary is always loaded as rawContent, even if it starts with ZSTD_MAGIC_DICTIONARY */
    ZSTD_dct_fullDict     /* refuses to load a dictionary if it does not respect Zstandard's specification */
} ZSTD_dictContentType_e;

typedef enum {
    ZSTD_dlm_byCopy = 0, 
    ZSTD_dlm_byRef,      
} ZSTD_dictLoadMethod_e;



/***************************************
*  Frame size functions
***************************************/

ZSTDLIB_API size_t ZSTD_findFrameCompressedSize(const void* src, size_t srcSize);

ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);

ZSTDLIB_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);


/***************************************
*  Memory management
***************************************/

ZSTDLIB_API size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
ZSTDLIB_API size_t ZSTD_sizeof_DCtx(const ZSTD_DCtx* dctx);
ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs);
ZSTDLIB_API size_t ZSTD_sizeof_DStream(const ZSTD_DStream* zds);
ZSTDLIB_API size_t ZSTD_sizeof_CDict(const ZSTD_CDict* cdict);
ZSTDLIB_API size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);

ZSTDLIB_API size_t ZSTD_estimateCCtxSize(int compressionLevel);
ZSTDLIB_API size_t ZSTD_estimateCCtxSize_usingCParams(ZSTD_compressionParameters cParams);
ZSTDLIB_API size_t ZSTD_estimateCCtxSize_usingCCtxParams(const ZSTD_CCtx_params* params);
ZSTDLIB_API size_t ZSTD_estimateDCtxSize(void);

ZSTDLIB_API size_t ZSTD_estimateCStreamSize(int compressionLevel);
ZSTDLIB_API size_t ZSTD_estimateCStreamSize_usingCParams(ZSTD_compressionParameters cParams);
ZSTDLIB_API size_t ZSTD_estimateCStreamSize_usingCCtxParams(const ZSTD_CCtx_params* params);
ZSTDLIB_API size_t ZSTD_estimateDStreamSize(size_t windowSize);
ZSTDLIB_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);

ZSTDLIB_API size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
ZSTDLIB_API size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, ZSTD_dictLoadMethod_e dictLoadMethod);
ZSTDLIB_API size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod);

ZSTDLIB_API ZSTD_CCtx*    ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize);
ZSTDLIB_API ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize);    
ZSTDLIB_API ZSTD_DCtx*    ZSTD_initStaticDCtx(void* workspace, size_t workspaceSize);
ZSTDLIB_API ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize);    
ZSTDLIB_API const ZSTD_CDict* ZSTD_initStaticCDict(
                                        void* workspace, size_t workspaceSize,
                                        const void* dict, size_t dictSize,
                                        ZSTD_dictLoadMethod_e dictLoadMethod,
                                        ZSTD_dictContentType_e dictContentType,
                                        ZSTD_compressionParameters cParams);

ZSTDLIB_API const ZSTD_DDict* ZSTD_initStaticDDict(
                                        void* workspace, size_t workspaceSize,
                                        const void* dict, size_t dictSize,
                                        ZSTD_dictLoadMethod_e dictLoadMethod,
                                        ZSTD_dictContentType_e dictContentType);

typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size);
typedef void  (*ZSTD_freeFunction) (void* opaque, void* address);
typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; void* opaque; } ZSTD_customMem;
static ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL };  
ZSTDLIB_API ZSTD_CCtx*    ZSTD_createCCtx_advanced(ZSTD_customMem customMem);
ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem);
ZSTDLIB_API ZSTD_DCtx*    ZSTD_createDCtx_advanced(ZSTD_customMem customMem);
ZSTDLIB_API ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem);

ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_advanced(const void* dict, size_t dictSize,
                                                  ZSTD_dictLoadMethod_e dictLoadMethod,
                                                  ZSTD_dictContentType_e dictContentType,
                                                  ZSTD_compressionParameters cParams,
                                                  ZSTD_customMem customMem);

ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize,
                                                  ZSTD_dictLoadMethod_e dictLoadMethod,
                                                  ZSTD_dictContentType_e dictContentType,
                                                  ZSTD_customMem customMem);



/***************************************
*  Advanced compression functions
***************************************/

ZSTDLIB_API ZSTD_CDict* ZSTD_createCDict_byReference(const void* dictBuffer, size_t dictSize, int compressionLevel);

ZSTDLIB_API ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize);

ZSTDLIB_API ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize);

ZSTDLIB_API size_t ZSTD_checkCParams(ZSTD_compressionParameters params);

ZSTDLIB_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize);

ZSTDLIB_API size_t ZSTD_compress_advanced (ZSTD_CCtx* cctx,
                                  void* dst, size_t dstCapacity,
                            const void* src, size_t srcSize,
                            const void* dict,size_t dictSize,
                                  ZSTD_parameters params);

ZSTDLIB_API size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
                                  void* dst, size_t dstCapacity,
                            const void* src, size_t srcSize,
                            const ZSTD_CDict* cdict, ZSTD_frameParameters fParams);


/*--- Advanced decompression functions ---*/

ZSTDLIB_API unsigned ZSTD_isFrame(const void* buffer, size_t size);

ZSTDLIB_API ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize);


ZSTDLIB_API unsigned ZSTD_getDictID_fromDict(const void* dict, size_t dictSize);

ZSTDLIB_API unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict);

ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize);


/********************************************************************
*  Advanced streaming functions
********************************************************************/

/*=====   Advanced Streaming compression functions  =====*/
ZSTDLIB_API size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize);   
ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); 
ZSTDLIB_API size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,
                                             ZSTD_parameters params, unsigned long long pledgedSrcSize);  
ZSTDLIB_API size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict);  
ZSTDLIB_API size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, ZSTD_frameParameters fParams, unsigned long long pledgedSrcSize);  
ZSTDLIB_API size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);


typedef struct {
    unsigned long long ingested;   /* nb input bytes read and buffered */
    unsigned long long consumed;   /* nb input bytes actually compressed */
    unsigned long long produced;   /* nb of compressed bytes generated and buffered */
    unsigned long long flushed;    /* nb of compressed bytes flushed : not provided; can be tracked from caller side */
    unsigned currentJobID;         /* MT only : latest started job nb */
    unsigned nbActiveWorkers;      /* MT only : nb of workers actively compressing at probe time */
} ZSTD_frameProgression;

/* ZSTD_getFrameProgression() :
 * tells how much data has been ingested (read from input)
 * consumed (input actually compressed) and produced (output) for current frame.
 * Note : (ingested - consumed) is amount of input data buffered internally, not yet compressed.
 * Aggregates progression inside active worker threads.
 */
ZSTDLIB_API ZSTD_frameProgression ZSTD_getFrameProgression(const ZSTD_CCtx* cctx);

ZSTDLIB_API size_t ZSTD_toFlushNow(ZSTD_CCtx* cctx);



/*=====   Advanced Streaming decompression functions  =====*/
typedef enum { DStream_p_maxWindowSize } ZSTD_DStreamParameter_e;
ZSTDLIB_API size_t ZSTD_setDStreamParameter(ZSTD_DStream* zds, ZSTD_DStreamParameter_e paramType, unsigned paramValue);   /* obsolete : this API will be removed in a future version */
ZSTDLIB_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize); 
ZSTDLIB_API size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict);  
ZSTDLIB_API size_t ZSTD_resetDStream(ZSTD_DStream* zds);  
/*********************************************************************
*  Buffer-less and synchronous inner streaming functions
*
*  This is an advanced API, giving full control over buffer management, for users which need direct control over memory.
*  But it's also a complex one, with several restrictions, documented below.
*  Prefer normal streaming API for an easier experience.
********************************************************************* */

/*=====   Buffer-less streaming compression functions  =====*/
ZSTDLIB_API size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel);
ZSTDLIB_API size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel);
ZSTDLIB_API size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize); 
ZSTDLIB_API size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict); 
ZSTDLIB_API size_t ZSTD_compressBegin_usingCDict_advanced(ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict, ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize);   /* compression parameters are already set within cdict. pledgedSrcSize must be correct. If srcSize is not known, use macro ZSTD_CONTENTSIZE_UNKNOWN */
ZSTDLIB_API size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize); 
ZSTDLIB_API size_t ZSTD_compressContinue(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
ZSTDLIB_API size_t ZSTD_compressEnd(ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);


/*-
  Buffer-less streaming decompression (synchronous mode)

  A ZSTD_DCtx object is required to track streaming operations.
  Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
  A ZSTD_DCtx object can be re-used multiple times.

  First typical operation is to retrieve frame parameters, using ZSTD_getFrameHeader().
  Frame header is extracted from the beginning of compressed frame, so providing only the frame's beginning is enough.
  Data fragment must be large enough to ensure successful decoding.
 `ZSTD_frameHeaderSize_max` bytes is guaranteed to always be large enough.
  @result : 0 : successful decoding, the `ZSTD_frameHeader` structure is correctly filled.
           >0 : `srcSize` is too small, please provide at least @result bytes on next attempt.
           errorCode, which can be tested using ZSTD_isError().

  It fills a ZSTD_frameHeader structure with important information to correctly decode the frame,
  such as the dictionary ID, content size, or maximum back-reference distance (`windowSize`).
  Note that these values could be wrong, either because of data corruption, or because a 3rd party deliberately spoofs false information.
  As a consequence, check that values remain within valid application range.
  For example, do not allocate memory blindly, check that `windowSize` is within expectation.
  Each application can set its own limits, depending on local restrictions.
  For extended interoperability, it is recommended to support `windowSize` of at least 8 MB.

  ZSTD_decompressContinue() needs previous data blocks during decompression, up to `windowSize` bytes.
  ZSTD_decompressContinue() is very sensitive to contiguity,
  if 2 blocks don't follow each other, make sure that either the compressor breaks contiguity at the same place,
  or that previous contiguous segment is large enough to properly handle maximum back-reference distance.
  There are multiple ways to guarantee this condition.

  The most memory efficient way is to use a round buffer of sufficient size.
  Sufficient size is determined by invoking ZSTD_decodingBufferSize_min(),
  which can @return an error code if required value is too large for current system (in 32-bits mode).
  In a round buffer methodology, ZSTD_decompressContinue() decompresses each block next to previous one,
  up to the moment there is not enough room left in the buffer to guarantee decoding another full block,
  which maximum size is provided in `ZSTD_frameHeader` structure, field `blockSizeMax`.
  At which point, decoding can resume from the beginning of the buffer.
  Note that already decoded data stored in the buffer should be flushed before being overwritten.

  There are alternatives possible, for example using two or more buffers of size `windowSize` each, though they consume more memory.

  Finally, if you control the compression process, you can also ignore all buffer size rules,
  as long as the encoder and decoder progress in "lock-step",
  aka use exactly the same buffer sizes, break contiguity at the same place, etc.

  Once buffers are setup, start decompression, with ZSTD_decompressBegin().
  If decompression requires a dictionary, use ZSTD_decompressBegin_usingDict() or ZSTD_decompressBegin_usingDDict().

  Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively.
  ZSTD_nextSrcSizeToDecompress() tells how many bytes to provide as 'srcSize' to ZSTD_decompressContinue().
  ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will fail.

 @result of ZSTD_decompressContinue() is the number of bytes regenerated within 'dst' (necessarily <= dstCapacity).
  It can be zero : it just means ZSTD_decompressContinue() has decoded some metadata item.
  It can also be an error code, which can be tested with ZSTD_isError().

  A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero.
  Context can then be reset to start a new decompression.

  Note : it's possible to know if next input to present is a header or a block, using ZSTD_nextInputType().
  This information is not required to properly decode a frame.

  == Special case : skippable frames ==

  Skippable frames allow integration of user-defined data into a flow of concatenated frames.
  Skippable frames will be ignored (skipped) by decompressor.
  The format of skippable frames is as follows :
  a) Skippable frame ID - 4 Bytes, Little endian format, any value from 0x184D2A50 to 0x184D2A5F
  b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits
  c) Frame Content - any content (User Data) of length equal to Frame Size
  For skippable frames ZSTD_getFrameHeader() returns zfhPtr->frameType==ZSTD_skippableFrame.
  For skippable frames ZSTD_decompressContinue() always returns 0 : it only skips the content.
*/

/*=====   Buffer-less streaming decompression functions  =====*/
typedef enum { ZSTD_frame, ZSTD_skippableFrame } ZSTD_frameType_e;
typedef struct {
    unsigned long long frameContentSize; /* if == ZSTD_CONTENTSIZE_UNKNOWN, it means this field is not available. 0 means "empty" */
    unsigned long long windowSize;       /* can be very large, up to <= frameContentSize */
    unsigned blockSizeMax;
    ZSTD_frameType_e frameType;          /* if == ZSTD_skippableFrame, frameContentSize is the size of skippable content */
    unsigned headerSize;
    unsigned dictID;
    unsigned checksumFlag;
} ZSTD_frameHeader;
ZSTDLIB_API size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize);   
ZSTDLIB_API size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize);  
ZSTDLIB_API size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx);
ZSTDLIB_API size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
ZSTDLIB_API size_t ZSTD_decompressBegin_usingDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);

ZSTDLIB_API size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx);
ZSTDLIB_API size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);

/* misc */
ZSTDLIB_API void   ZSTD_copyDCtx(ZSTD_DCtx* dctx, const ZSTD_DCtx* preparedDCtx);
typedef enum { ZSTDnit_frameHeader, ZSTDnit_blockHeader, ZSTDnit_block, ZSTDnit_lastBlock, ZSTDnit_checksum, ZSTDnit_skippableFrame } ZSTD_nextInputType_e;
ZSTDLIB_API ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx);



/* ============================================ */
/* ============================================ */

/* API design :
 *   In this advanced API, parameters are pushed one by one into an existing context,
 *   using ZSTD_CCtx_set*() functions.
 *   Pushed parameters are sticky : they are applied to next job, and any subsequent job.
 *   It's possible to reset parameters to "default" using ZSTD_CCtx_reset().
 *   Important : "sticky" parameters only work with `ZSTD_compress_generic()` !
 *               For any other entry point, "sticky" parameters are ignored !
 *
 *   This API is intended to replace all others advanced / experimental API entry points.
 */

/* note on enum design :
 * All enum will be pinned to explicit values before reaching "stable API" status */

typedef enum {
    /* Opened question : should we have a format ZSTD_f_auto ?
     * Today, it would mean exactly the same as ZSTD_f_zstd1.
     * But, in the future, should several formats become supported,
     * on the compression side, it would mean "default format".
     * On the decompression side, it would mean "automatic format detection",
     * so that ZSTD_f_zstd1 would mean "accept *only* zstd frames".
     * Since meaning is a little different, another option could be to define different enums for compression and decompression.
     * This question could be kept for later, when there are actually multiple formats to support,
     * but there is also the question of pinning enum values, and pinning value `0` is especially important */
    ZSTD_f_zstd1 = 0,        /* zstd frame format, specified in zstd_compression_format.md (default) */
    ZSTD_f_zstd1_magicless,  /* Variant of zstd frame format, without initial 4-bytes magic number.
                              * Useful to save 4 bytes per generated frame.
                              * Decoder cannot recognise automatically this format, requiring instructions. */
} ZSTD_format_e;

typedef enum {
    /* compression format */
    ZSTD_p_format = 10,      /* See ZSTD_format_e enum definition.
                              * Cast selected format as unsigned for ZSTD_CCtx_setParameter() compatibility. */

    /* compression parameters */
    ZSTD_p_compressionLevel=100, /* Update all compression parameters according to pre-defined cLevel table
                              * Default level is ZSTD_CLEVEL_DEFAULT==3.
                              * Special: value 0 means default, which is controlled by ZSTD_CLEVEL_DEFAULT.
                              * Note 1 : it's possible to pass a negative compression level by casting it to unsigned type.
                              * Note 2 : setting a level sets all default values of other compression parameters.
                              * Note 3 : setting compressionLevel automatically updates ZSTD_p_compressLiterals. */
    ZSTD_p_windowLog,        /* Maximum allowed back-reference distance, expressed as power of 2.
                              * Must be clamped between ZSTD_WINDOWLOG_MIN and ZSTD_WINDOWLOG_MAX.
                              * Special: value 0 means "use default windowLog".
                              * Note: Using a window size greater than ZSTD_MAXWINDOWSIZE_DEFAULT (default: 2^27)
                              *       requires explicitly allowing such window size during decompression stage. */
    ZSTD_p_hashLog,          /* Size of the initial probe table, as a power of 2.
                              * Resulting table size is (1 << (hashLog+2)).
                              * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX.
                              * Larger tables improve compression ratio of strategies <= dFast,
                              * and improve speed of strategies > dFast.
                              * Special: value 0 means "use default hashLog". */
    ZSTD_p_chainLog,         /* Size of the multi-probe search table, as a power of 2.
                              * Resulting table size is (1 << (chainLog+2)).
                              * Must be clamped between ZSTD_CHAINLOG_MIN and ZSTD_CHAINLOG_MAX.
                              * Larger tables result in better and slower compression.
                              * This parameter is useless when using "fast" strategy.
                              * Note it's still useful when using "dfast" strategy,
                              * in which case it defines a secondary probe table.
                              * Special: value 0 means "use default chainLog". */
    ZSTD_p_searchLog,        /* Number of search attempts, as a power of 2.
                              * More attempts result in better and slower compression.
                              * This parameter is useless when using "fast" and "dFast" strategies.
                              * Special: value 0 means "use default searchLog". */
    ZSTD_p_minMatch,         /* Minimum size of searched matches (note : repCode matches can be smaller).
                              * Larger values make faster compression and decompression, but decrease ratio.
                              * Must be clamped between ZSTD_SEARCHLENGTH_MIN and ZSTD_SEARCHLENGTH_MAX.
                              * Note that currently, for all strategies < btopt, effective minimum is 4.
                              *                    , for all strategies > fast, effective maximum is 6.
                              * Special: value 0 means "use default minMatchLength". */
    ZSTD_p_targetLength,     /* Impact of this field depends on strategy.
                              * For strategies btopt & btultra:
                              *     Length of Match considered "good enough" to stop search.
                              *     Larger values make compression stronger, and slower.
                              * For strategy fast:
                              *     Distance between match sampling.
                              *     Larger values make compression faster, and weaker.
                              * Special: value 0 means "use default targetLength". */
    ZSTD_p_compressionStrategy, /* See ZSTD_strategy enum definition.
                              * Cast selected strategy as unsigned for ZSTD_CCtx_setParameter() compatibility.
                              * The higher the value of selected strategy, the more complex it is,
                              * resulting in stronger and slower compression.
                              * Special: value 0 means "use default strategy". */

    ZSTD_p_enableLongDistanceMatching=160, /* Enable long distance matching.
                                         * This parameter is designed to improve compression ratio
                                         * for large inputs, by finding large matches at long distance.
                                         * It increases memory usage and window size.
                                         * Note: enabling this parameter increases ZSTD_p_windowLog to 128 MB
                                         * except when expressly set to a different value. */
    ZSTD_p_ldmHashLog,       /* Size of the table for long distance matching, as a power of 2.
                              * Larger values increase memory usage and compression ratio,
                              * but decrease compression speed.
                              * Must be clamped between ZSTD_HASHLOG_MIN and ZSTD_HASHLOG_MAX
                              * default: windowlog - 7.
                              * Special: value 0 means "automatically determine hashlog". */
    ZSTD_p_ldmMinMatch,      /* Minimum match size for long distance matcher.
                              * Larger/too small values usually decrease compression ratio.
                              * Must be clamped between ZSTD_LDM_MINMATCH_MIN and ZSTD_LDM_MINMATCH_MAX.
                              * Special: value 0 means "use default value" (default: 64). */
    ZSTD_p_ldmBucketSizeLog, /* Log size of each bucket in the LDM hash table for collision resolution.
                              * Larger values improve collision resolution but decrease compression speed.
                              * The maximum value is ZSTD_LDM_BUCKETSIZELOG_MAX .
                              * Special: value 0 means "use default value" (default: 3). */
    ZSTD_p_ldmHashEveryLog,  /* Frequency of inserting/looking up entries in the LDM hash table.
                              * Must be clamped between 0 and (ZSTD_WINDOWLOG_MAX - ZSTD_HASHLOG_MIN).
                              * Default is MAX(0, (windowLog - ldmHashLog)), optimizing hash table usage.
                              * Larger values improve compression speed.
                              * Deviating far from default value will likely result in a compression ratio decrease.
                              * Special: value 0 means "automatically determine hashEveryLog". */

    /* frame parameters */
    ZSTD_p_contentSizeFlag=200, /* Content size will be written into frame header _whenever known_ (default:1)
                              * Content size must be known at the beginning of compression,
                              * it is provided using ZSTD_CCtx_setPledgedSrcSize() */
    ZSTD_p_checksumFlag,     /* A 32-bits checksum of content is written at end of frame (default:0) */
    ZSTD_p_dictIDFlag,       /* When applicable, dictionary's ID is written into frame header (default:1) */

    /* multi-threading parameters */
    /* These parameters are only useful if multi-threading is enabled (ZSTD_MULTITHREAD).
     * They return an error otherwise. */
    ZSTD_p_nbWorkers=400,    /* Select how many threads will be spawned to compress in parallel.
                              * When nbWorkers >= 1, triggers asynchronous mode :
                              * ZSTD_compress_generic() consumes some input, flush some output if possible, and immediately gives back control to caller,
                              * while compression work is performed in parallel, within worker threads.
                              * (note : a strong exception to this rule is when first invocation sets ZSTD_e_end : it becomes a blocking call).
                              * More workers improve speed, but also increase memory usage.
                              * Default value is `0`, aka "single-threaded mode" : no worker is spawned, compression is performed inside Caller's thread, all invocations are blocking */
    ZSTD_p_jobSize,          /* Size of a compression job. This value is enforced only in non-blocking mode.
                              * Each compression job is completed in parallel, so this value indirectly controls the nb of active threads.
                              * 0 means default, which is dynamically determined based on compression parameters.
                              * Job size must be a minimum of overlapSize, or 1 MB, whichever is largest.
                              * The minimum size is automatically and transparently enforced */
    ZSTD_p_overlapSizeLog,   /* Size of previous input reloaded at the beginning of each job.
                              * 0 => no overlap, 6(default) => use 1/8th of windowSize, >=9 => use full windowSize */

    /* =================================================================== */
    /* experimental parameters - no stability guaranteed                   */
    /* =================================================================== */

    ZSTD_p_forceMaxWindow=1100, /* Force back-reference distances to remain < windowSize,
                              * even when referencing into Dictionary content (default:0) */
    ZSTD_p_forceAttachDict,  /* ZSTD supports usage of a CDict in-place
                              * (avoiding having to copy the compression tables
                              * from the CDict into the working context). Using
                              * a CDict in this way saves an initial setup step,
                              * but comes at the cost of more work per byte of
                              * input. ZSTD has a simple internal heuristic that
                              * guesses which strategy will be faster. You can
                              * use this flag to override that guess.
                              *
                              * Note that the by-reference, in-place strategy is
                              * only used when reusing a compression context
                              * with compatible compression parameters. (If
                              * incompatible / uninitialized, the working
                              * context needs to be cleared anyways, which is
                              * about as expensive as overwriting it with the
                              * dictionary context, so there's no savings in
                              * using the CDict by-ref.)
                              *
                              * Values greater than 0 force attaching the dict.
                              * Values less than 0 force copying the dict.
                              * 0 selects the default heuristic-guided behavior.
                              */

} ZSTD_cParameter;


ZSTDLIB_API size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value);

ZSTDLIB_API size_t ZSTD_CCtx_getParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned* value);

ZSTDLIB_API size_t ZSTD_CCtx_setPledgedSrcSize(ZSTD_CCtx* cctx, unsigned long long pledgedSrcSize);

ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary_byReference(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
ZSTDLIB_API size_t ZSTD_CCtx_loadDictionary_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType);


ZSTDLIB_API size_t ZSTD_CCtx_refCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict);

ZSTDLIB_API size_t ZSTD_CCtx_refPrefix(ZSTD_CCtx* cctx,
                                       const void* prefix, size_t prefixSize);
ZSTDLIB_API size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx,
                                       const void* prefix, size_t prefixSize,
                                       ZSTD_dictContentType_e dictContentType);

ZSTDLIB_API void ZSTD_CCtx_reset(ZSTD_CCtx* cctx);

ZSTDLIB_API size_t ZSTD_CCtx_resetParameters(ZSTD_CCtx* cctx);



typedef enum {
    ZSTD_e_continue=0, /* collect more data, encoder decides when to output compressed result, for optimal compression ratio */
    ZSTD_e_flush,      /* flush any data provided so far,
                        * it creates (at least) one new block, that can be decoded immediately on reception;
                        * frame will continue: any future data can still reference previously compressed data, improving compression. */
    ZSTD_e_end         /* flush any remaining data and close current frame.
                        * any additional data starts a new frame.
                        * each frame is independent (does not reference any content from previous frame). */
} ZSTD_EndDirective;

ZSTDLIB_API size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
                                          ZSTD_outBuffer* output,
                                          ZSTD_inBuffer* input,
                                          ZSTD_EndDirective endOp);


ZSTDLIB_API size_t ZSTD_compress_generic_simpleArgs (
                            ZSTD_CCtx* cctx,
                            void* dst, size_t dstCapacity, size_t* dstPos,
                      const void* src, size_t srcSize, size_t* srcPos,
                            ZSTD_EndDirective endOp);


ZSTDLIB_API ZSTD_CCtx_params* ZSTD_createCCtxParams(void);
ZSTDLIB_API size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);


ZSTDLIB_API size_t ZSTD_CCtxParams_reset(ZSTD_CCtx_params* params);

ZSTDLIB_API size_t ZSTD_CCtxParams_init(ZSTD_CCtx_params* cctxParams, int compressionLevel);

ZSTDLIB_API size_t ZSTD_CCtxParams_init_advanced(ZSTD_CCtx_params* cctxParams, ZSTD_parameters params);


ZSTDLIB_API size_t ZSTD_CCtxParam_setParameter(ZSTD_CCtx_params* params, ZSTD_cParameter param, unsigned value);

ZSTDLIB_API size_t ZSTD_CCtxParam_getParameter(ZSTD_CCtx_params* params, ZSTD_cParameter param, unsigned* value);

ZSTDLIB_API size_t ZSTD_CCtx_setParametersUsingCCtxParams(
        ZSTD_CCtx* cctx, const ZSTD_CCtx_params* params);


/* ==================================== */
/*===   Advanced decompression API   ===*/
/* ==================================== */

/* The following API works the same way as the advanced compression API :
 * a context is created, parameters are pushed into it one by one,
 * then the context can be used to decompress data using an interface similar to the straming API.
 */

ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
ZSTDLIB_API size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType);


ZSTDLIB_API size_t ZSTD_DCtx_refDDict(ZSTD_DCtx* dctx, const ZSTD_DDict* ddict);


ZSTDLIB_API size_t ZSTD_DCtx_refPrefix(ZSTD_DCtx* dctx,
                                    const void* prefix, size_t prefixSize);
ZSTDLIB_API size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx,
                                    const void* prefix, size_t prefixSize,
                                    ZSTD_dictContentType_e dictContentType);


ZSTDLIB_API size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize);


ZSTDLIB_API size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format);


ZSTDLIB_API size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr,
                        const void* src, size_t srcSize, ZSTD_format_e format);


ZSTDLIB_API size_t ZSTD_decompress_generic(ZSTD_DCtx* dctx,
                                           ZSTD_outBuffer* output,
                                           ZSTD_inBuffer* input);


ZSTDLIB_API size_t ZSTD_decompress_generic_simpleArgs (
                            ZSTD_DCtx* dctx,
                            void* dst, size_t dstCapacity, size_t* dstPos,
                      const void* src, size_t srcSize, size_t* srcPos);


ZSTDLIB_API void ZSTD_DCtx_reset(ZSTD_DCtx* dctx);



/* ============================ */
/* ============================ */

/*=====   Raw zstd block functions  =====*/
ZSTDLIB_API size_t ZSTD_getBlockSize   (const ZSTD_CCtx* cctx);
ZSTDLIB_API size_t ZSTD_compressBlock  (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
ZSTDLIB_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
ZSTDLIB_API size_t ZSTD_insertBlock    (ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize);  
#endif   /* ZSTD_H_ZSTD_STATIC_LINKING_ONLY */

#if defined (__cplusplus)
}
#endif