188 lines
8.5 KiB
C
188 lines
8.5 KiB
C
/*
|
|
* Copyright (c) Yann Collet, Meta Platforms, Inc. and affiliates.
|
|
* 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 ZSTDv07_H_235446
|
|
#define ZSTDv07_H_235446
|
|
|
|
#if defined (__cplusplus)
|
|
extern "C" {
|
|
#endif
|
|
|
|
/*====== Dependency ======*/
|
|
#include <stddef.h> /* size_t */
|
|
|
|
|
|
/*====== Export for Windows ======*/
|
|
/*!
|
|
* ZSTDv07_DLL_EXPORT :
|
|
* Enable exporting of functions when building a Windows DLL
|
|
*/
|
|
#if defined(_WIN32) && defined(ZSTDv07_DLL_EXPORT) && (ZSTDv07_DLL_EXPORT==1)
|
|
# define ZSTDLIBv07_API __declspec(dllexport)
|
|
#else
|
|
# define ZSTDLIBv07_API
|
|
#endif
|
|
|
|
|
|
/* *************************************
|
|
* Simple API
|
|
***************************************/
|
|
/*! ZSTDv07_getDecompressedSize() :
|
|
* @return : decompressed size if known, 0 otherwise.
|
|
note 1 : if `0`, follow up with ZSTDv07_getFrameParams() to know precise failure cause.
|
|
note 2 : decompressed size could be wrong or intentionally modified !
|
|
always ensure results fit within application's authorized limits */
|
|
unsigned long long ZSTDv07_getDecompressedSize(const void* src, size_t srcSize);
|
|
|
|
/*! ZSTDv07_decompress() :
|
|
`compressedSize` : must be _exact_ size of compressed input, otherwise decompression will fail.
|
|
`dstCapacity` must be 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 ZSTDv07_isError()) */
|
|
ZSTDLIBv07_API size_t ZSTDv07_decompress( void* dst, size_t dstCapacity,
|
|
const void* src, size_t compressedSize);
|
|
|
|
/**
|
|
ZSTDv07_findFrameSizeInfoLegacy() : get the source length and decompressed bound of a ZSTD frame compliant with v0.7.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 ZSTDv07_findFrameSizeInfoLegacy(const void *src, size_t srcSize,
|
|
size_t* cSize, unsigned long long* dBound);
|
|
|
|
/*====== Helper functions ======*/
|
|
ZSTDLIBv07_API unsigned ZSTDv07_isError(size_t code); /*!< tells if a `size_t` function result is an error code */
|
|
ZSTDLIBv07_API const char* ZSTDv07_getErrorName(size_t code); /*!< provides readable string from an error code */
|
|
|
|
|
|
/*-*************************************
|
|
* Explicit memory management
|
|
***************************************/
|
|
/** Decompression context */
|
|
typedef struct ZSTDv07_DCtx_s ZSTDv07_DCtx;
|
|
ZSTDLIBv07_API ZSTDv07_DCtx* ZSTDv07_createDCtx(void);
|
|
ZSTDLIBv07_API size_t ZSTDv07_freeDCtx(ZSTDv07_DCtx* dctx); /*!< @return : errorCode */
|
|
|
|
/** ZSTDv07_decompressDCtx() :
|
|
* Same as ZSTDv07_decompress(), requires an allocated ZSTDv07_DCtx (see ZSTDv07_createDCtx()) */
|
|
ZSTDLIBv07_API size_t ZSTDv07_decompressDCtx(ZSTDv07_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
|
|
|
|
|
|
/*-************************
|
|
* Simple dictionary API
|
|
***************************/
|
|
/*! ZSTDv07_decompress_usingDict() :
|
|
* Decompression using a pre-defined Dictionary content (see dictBuilder).
|
|
* Dictionary must be identical to the one used during compression.
|
|
* Note : This function load the dictionary, resulting in a significant startup time */
|
|
ZSTDLIBv07_API size_t ZSTDv07_decompress_usingDict(ZSTDv07_DCtx* dctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize,
|
|
const void* dict,size_t dictSize);
|
|
|
|
|
|
/*-**************************
|
|
* Advanced Dictionary API
|
|
****************************/
|
|
/*! ZSTDv07_createDDict() :
|
|
* Create a digested dictionary, ready to start decompression operation without startup delay.
|
|
* `dict` can be released after creation */
|
|
typedef struct ZSTDv07_DDict_s ZSTDv07_DDict;
|
|
ZSTDLIBv07_API ZSTDv07_DDict* ZSTDv07_createDDict(const void* dict, size_t dictSize);
|
|
ZSTDLIBv07_API size_t ZSTDv07_freeDDict(ZSTDv07_DDict* ddict);
|
|
|
|
/*! ZSTDv07_decompress_usingDDict() :
|
|
* Decompression using a pre-digested Dictionary
|
|
* Faster startup than ZSTDv07_decompress_usingDict(), recommended when same dictionary is used multiple times. */
|
|
ZSTDLIBv07_API size_t ZSTDv07_decompress_usingDDict(ZSTDv07_DCtx* dctx,
|
|
void* dst, size_t dstCapacity,
|
|
const void* src, size_t srcSize,
|
|
const ZSTDv07_DDict* ddict);
|
|
|
|
typedef struct {
|
|
unsigned long long frameContentSize;
|
|
unsigned windowSize;
|
|
unsigned dictID;
|
|
unsigned checksumFlag;
|
|
} ZSTDv07_frameParams;
|
|
|
|
ZSTDLIBv07_API size_t ZSTDv07_getFrameParams(ZSTDv07_frameParams* fparamsPtr, const void* src, size_t srcSize); /**< doesn't consume input */
|
|
|
|
|
|
|
|
|
|
/* *************************************
|
|
* Streaming functions
|
|
***************************************/
|
|
typedef struct ZBUFFv07_DCtx_s ZBUFFv07_DCtx;
|
|
ZSTDLIBv07_API ZBUFFv07_DCtx* ZBUFFv07_createDCtx(void);
|
|
ZSTDLIBv07_API size_t ZBUFFv07_freeDCtx(ZBUFFv07_DCtx* dctx);
|
|
|
|
ZSTDLIBv07_API size_t ZBUFFv07_decompressInit(ZBUFFv07_DCtx* dctx);
|
|
ZSTDLIBv07_API size_t ZBUFFv07_decompressInitDictionary(ZBUFFv07_DCtx* dctx, const void* dict, size_t dictSize);
|
|
|
|
ZSTDLIBv07_API size_t ZBUFFv07_decompressContinue(ZBUFFv07_DCtx* dctx,
|
|
void* dst, size_t* dstCapacityPtr,
|
|
const void* src, size_t* srcSizePtr);
|
|
|
|
/*-***************************************************************************
|
|
* Streaming decompression howto
|
|
*
|
|
* A ZBUFFv07_DCtx object is required to track streaming operations.
|
|
* Use ZBUFFv07_createDCtx() and ZBUFFv07_freeDCtx() to create/release resources.
|
|
* Use ZBUFFv07_decompressInit() to start a new decompression operation,
|
|
* or ZBUFFv07_decompressInitDictionary() if decompression requires a dictionary.
|
|
* Note that ZBUFFv07_DCtx objects can be re-init multiple times.
|
|
*
|
|
* Use ZBUFFv07_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 ZBUFFv07_isError().
|
|
*
|
|
* Hint : recommended buffer sizes (not compulsory) : ZBUFFv07_recommendedDInSize() and ZBUFFv07_recommendedDOutSize()
|
|
* output : ZBUFFv07_recommendedDOutSize== 128 KB block size is the internal unit, it ensures it's always possible to write a full block when decoded.
|
|
* input : ZBUFFv07_recommendedDInSize == 128KB + 3;
|
|
* just follow indications from ZBUFFv07_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 .
|
|
* *******************************************************************************/
|
|
|
|
|
|
/* *************************************
|
|
* Tool functions
|
|
***************************************/
|
|
ZSTDLIBv07_API unsigned ZBUFFv07_isError(size_t errorCode);
|
|
ZSTDLIBv07_API const char* ZBUFFv07_getErrorName(size_t errorCode);
|
|
|
|
/** Functions below provide recommended buffer sizes for Compression or Decompression operations.
|
|
* These sizes are just hints, they tend to offer better latency */
|
|
ZSTDLIBv07_API size_t ZBUFFv07_recommendedDInSize(void);
|
|
ZSTDLIBv07_API size_t ZBUFFv07_recommendedDOutSize(void);
|
|
|
|
|
|
/*-*************************************
|
|
* Constants
|
|
***************************************/
|
|
#define ZSTDv07_MAGICNUMBER 0xFD2FB527 /* v0.7 */
|
|
|
|
|
|
#if defined (__cplusplus)
|
|
}
|
|
#endif
|
|
|
|
#endif /* ZSTDv07_H_235446 */
|