/** * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. * All rights reserved. * * This source code is licensed under the BSD-style license found in the * LICENSE file in the root directory of this source tree. An additional grant * of patent rights can be found in the PATENTS file in the same directory. */ #ifndef ZSTDv06_H #define ZSTDv06_H #if defined (__cplusplus) extern "C" { #endif /*-************************************* * Dependencies ***************************************/ #include /* size_t */ /*-*************************************************************** * Export parameters *****************************************************************/ /*! * ZSTDv06_DLL_EXPORT : * Enable exporting of functions when building a Windows DLL */ #if defined(_WIN32) && defined(ZSTDv06_DLL_EXPORT) && (ZSTDv06_DLL_EXPORT==1) # define ZSTDLIB_API __declspec(dllexport) #else # define ZSTDLIB_API #endif /* ************************************* * Simple functions ***************************************/ /*! ZSTDv06_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 ZSTDv06_isError()) */ ZSTDLIB_API size_t ZSTDv06_decompress( void* dst, size_t dstCapacity, const void* src, size_t compressedSize); /* ************************************* * Helper functions ***************************************/ ZSTDLIB_API size_t ZSTDv06_compressBound(size_t srcSize); /*!< maximum compressed size (worst case scenario) */ /* Error Management */ ZSTDLIB_API unsigned ZSTDv06_isError(size_t code); /*!< tells if a `size_t` function result is an error code */ ZSTDLIB_API const char* ZSTDv06_getErrorName(size_t code); /*!< provides readable string for an error code */ /* ************************************* * Explicit memory management ***************************************/ /** Decompression context */ typedef struct ZSTDv06_DCtx_s ZSTDv06_DCtx; ZSTDLIB_API ZSTDv06_DCtx* ZSTDv06_createDCtx(void); ZSTDLIB_API size_t ZSTDv06_freeDCtx(ZSTDv06_DCtx* dctx); /*!< @return : errorCode */ /** ZSTDv06_decompressDCtx() : * Same as ZSTDv06_decompress(), but requires an already allocated ZSTDv06_DCtx (see ZSTDv06_createDCtx()) */ ZSTDLIB_API size_t ZSTDv06_decompressDCtx(ZSTDv06_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); /*-*********************** * Dictionary API *************************/ /*! ZSTDv06_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 ZSTDv06_decompressDCtx() */ ZSTDLIB_API size_t ZSTDv06_decompress_usingDict(ZSTDv06_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize, const void* dict,size_t dictSize); /*-************************ * Advanced Streaming API ***************************/ struct ZSTDv06_frameParams_s { unsigned long long frameContentSize; unsigned windowLog; }; typedef struct ZSTDv06_frameParams_s ZSTDv06_frameParams; ZSTDLIB_API size_t ZSTDv06_getFrameParams(ZSTDv06_frameParams* fparamsPtr, const void* src, size_t srcSize); /**< doesn't consume input */ ZSTDLIB_API size_t ZSTDv06_decompressBegin_usingDict(ZSTDv06_DCtx* dctx, const void* dict, size_t dictSize); ZSTDLIB_API void ZSTDv06_copyDCtx(ZSTDv06_DCtx* dctx, const ZSTDv06_DCtx* preparedDCtx); ZSTDLIB_API size_t ZSTDv06_nextSrcSizeToDecompress(ZSTDv06_DCtx* dctx); ZSTDLIB_API size_t ZSTDv06_decompressContinue(ZSTDv06_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); /* ************************************* * ZBUFF API ***************************************/ typedef struct ZBUFFv06_DCtx_s ZBUFFv06_DCtx; ZSTDLIB_API ZBUFFv06_DCtx* ZBUFFv06_createDCtx(void); ZSTDLIB_API size_t ZBUFFv06_freeDCtx(ZBUFFv06_DCtx* dctx); ZSTDLIB_API size_t ZBUFFv06_decompressInit(ZBUFFv06_DCtx* dctx); ZSTDLIB_API size_t ZBUFFv06_decompressInitDictionary(ZBUFFv06_DCtx* dctx, const void* dict, size_t dictSize); ZSTDLIB_API size_t ZBUFFv06_decompressContinue(ZBUFFv06_DCtx* dctx, void* dst, size_t* dstCapacityPtr, const void* src, size_t* srcSizePtr); /*-*************************************************************************** * Streaming decompression howto * * A ZBUFFv06_DCtx object is required to track streaming operations. * Use ZBUFFv06_createDCtx() and ZBUFFv06_freeDCtx() to create/release resources. * Use ZBUFFv06_decompressInit() to start a new decompression operation, * or ZBUFFv06_decompressInitDictionary() if decompression requires a dictionary. * Note that ZBUFFv06_DCtx objects can be re-init multiple times. * * Use ZBUFFv06_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 ZBUFFv06_isError(). * * Hint : recommended buffer sizes (not compulsory) : ZBUFFv06_recommendedDInSize() and ZBUFFv06_recommendedDOutSize() * output : ZBUFFv06_recommendedDOutSize== 128 KB block size is the internal unit, it ensures it's always possible to write a full block when decoded. * input : ZBUFFv06_recommendedDInSize == 128KB + 3; * just follow indications from ZBUFFv06_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 . * *******************************************************************************/ /* ************************************* * Tool functions ***************************************/ ZSTDLIB_API unsigned ZBUFFv06_isError(size_t errorCode); ZSTDLIB_API const char* ZBUFFv06_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 */ ZSTDLIB_API size_t ZBUFFv06_recommendedDInSize(void); ZSTDLIB_API size_t ZBUFFv06_recommendedDOutSize(void); /*-************************************* * Constants ***************************************/ #define ZSTDv06_MAGICNUMBER 0xFD2FB526 /* v0.6 */ #if defined (__cplusplus) } #endif #endif /* ZSTDv06_BUFFERED_H */