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/*
* Copyright (c) 2016-2020, 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.
*/
#ifndef ZSTDv05_H
#define ZSTDv05_H
#if defined (__cplusplus)
extern "C" {
#endif
/*-*************************************
* Dependencies
***************************************/
#include <stddef.h> /* size_t */
#include "../common/mem.h" /* U64, U32 */
/* *************************************
* Simple functions
***************************************/
/*! ZSTDv05_decompress() :
`compressedSize` : is the _exact_ size of the compressed blob, otherwise decompression will fail.
`dstCapacity` must be large enough, equal or larger than originalSize.
@return : the number of bytes decompressed into `dst` (<= `dstCapacity`),
or an errorCode if it fails (which can be tested using ZSTDv05_isError()) */
size_t ZSTDv05_decompress( void* dst, size_t dstCapacity,
const void* src, size_t compressedSize);
/**
ZSTDv05_findFrameSizeInfoLegacy() : get the source length and decompressed bound of a ZSTD frame compliant with v0.5.x format
srcSize : The size of the 'src' buffer, at least as large as the frame pointed to by 'src'
cSize (output parameter) : the number of bytes that would be read to decompress this frame
or an error code if it fails (which can be tested using ZSTDv01_isError())
dBound (output parameter) : an upper-bound for the decompressed size of the data in the frame
or ZSTD_CONTENTSIZE_ERROR if an error occurs
note : assumes `cSize` and `dBound` are _not_ NULL.
*/
void ZSTDv05_findFrameSizeInfoLegacy(const void *src, size_t srcSize,
size_t* cSize, unsigned long long* dBound);
/* *************************************
* Helper functions
***************************************/
/* Error Management */
unsigned ZSTDv05_isError(size_t code); /*!< tells if a `size_t` function result is an error code */
const char* ZSTDv05_getErrorName(size_t code); /*!< provides readable string for an error code */
/* *************************************
* Explicit memory management
***************************************/
/** Decompression context */
typedef struct ZSTDv05_DCtx_s ZSTDv05_DCtx;
ZSTDv05_DCtx* ZSTDv05_createDCtx(void);
size_t ZSTDv05_freeDCtx(ZSTDv05_DCtx* dctx); /*!< @return : errorCode */
/** ZSTDv05_decompressDCtx() :
* Same as ZSTDv05_decompress(), but requires an already allocated ZSTDv05_DCtx (see ZSTDv05_createDCtx()) */
size_t ZSTDv05_decompressDCtx(ZSTDv05_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
/*-***********************
* Simple Dictionary API
*************************/
/*! ZSTDv05_decompress_usingDict() :
* Decompression using a pre-defined Dictionary content (see dictBuilder).
* Dictionary must be identical to the one used during compression, otherwise regenerated data will be corrupted.
* Note : dict can be NULL, in which case, it's equivalent to ZSTDv05_decompressDCtx() */
size_t ZSTDv05_decompress_usingDict(ZSTDv05_DCtx* dctx,
void* dst, size_t dstCapacity,
const void* src, size_t srcSize,
const void* dict,size_t dictSize);
/*-************************
* Advanced Streaming API
***************************/
typedef enum { ZSTDv05_fast, ZSTDv05_greedy, ZSTDv05_lazy, ZSTDv05_lazy2, ZSTDv05_btlazy2, ZSTDv05_opt, ZSTDv05_btopt } ZSTDv05_strategy;
typedef struct {
U64 srcSize;
U32 windowLog; /* the only useful information to retrieve */
U32 contentLog; U32 hashLog; U32 searchLog; U32 searchLength; U32 targetLength; ZSTDv05_strategy strategy;
} ZSTDv05_parameters;
size_t ZSTDv05_getFrameParams(ZSTDv05_parameters* params, const void* src, size_t srcSize);
size_t ZSTDv05_decompressBegin_usingDict(ZSTDv05_DCtx* dctx, const void* dict, size_t dictSize);
void ZSTDv05_copyDCtx(ZSTDv05_DCtx* dstDCtx, const ZSTDv05_DCtx* srcDCtx);
size_t ZSTDv05_nextSrcSizeToDecompress(ZSTDv05_DCtx* dctx);
size_t ZSTDv05_decompressContinue(ZSTDv05_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
/*-***********************
* ZBUFF API
*************************/
typedef struct ZBUFFv05_DCtx_s ZBUFFv05_DCtx;
ZBUFFv05_DCtx* ZBUFFv05_createDCtx(void);
size_t ZBUFFv05_freeDCtx(ZBUFFv05_DCtx* dctx);
size_t ZBUFFv05_decompressInit(ZBUFFv05_DCtx* dctx);
size_t ZBUFFv05_decompressInitDictionary(ZBUFFv05_DCtx* dctx, const void* dict, size_t dictSize);
size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* dctx,
void* dst, size_t* dstCapacityPtr,
const void* src, size_t* srcSizePtr);
/*-***************************************************************************
* Streaming decompression
*
* A ZBUFFv05_DCtx object is required to track streaming operations.
* Use ZBUFFv05_createDCtx() and ZBUFFv05_freeDCtx() to create/release resources.
* Use ZBUFFv05_decompressInit() to start a new decompression operation,
* or ZBUFFv05_decompressInitDictionary() if decompression requires a dictionary.
* Note that ZBUFFv05_DCtx objects can be reused multiple times.
*
* Use ZBUFFv05_decompressContinue() repetitively to consume your input.
* *srcSizePtr and *dstCapacityPtr can be any size.
* The function will report how many bytes were read or written by modifying *srcSizePtr and *dstCapacityPtr.
* Note that it may not consume the entire input, in which case it's up to the caller to present remaining input again.
* The content of @dst will be overwritten (up to *dstCapacityPtr) at each function call, so save its content if it matters or change @dst.
* @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to help latency)
* or 0 when a frame is completely decoded
* or an error code, which can be tested using ZBUFFv05_isError().
*
* Hint : recommended buffer sizes (not compulsory) : ZBUFFv05_recommendedDInSize() / ZBUFFv05_recommendedDOutSize()
* output : ZBUFFv05_recommendedDOutSize==128 KB block size is the internal unit, it ensures it's always possible to write a full block when decoded.
* input : ZBUFFv05_recommendedDInSize==128Kb+3; just follow indications from ZBUFFv05_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 .
* *******************************************************************************/
/* *************************************
* Tool functions
***************************************/
unsigned ZBUFFv05_isError(size_t errorCode);
const char* ZBUFFv05_getErrorName(size_t errorCode);
/** Functions below provide recommended buffer sizes for Compression or Decompression operations.
* These sizes are just hints, and tend to offer better latency */
size_t ZBUFFv05_recommendedDInSize(void);
size_t ZBUFFv05_recommendedDOutSize(void);
/*-*************************************
* Constants
***************************************/
#define ZSTDv05_MAGICNUMBER 0xFD2FB525 /* v0.5 */
#if defined (__cplusplus)
}
#endif
#endif /* ZSTDv0505_H */
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