diff options
Diffstat (limited to 'src/zstd/lib/legacy/zstd_v04.h')
| -rw-r--r-- | src/zstd/lib/legacy/zstd_v04.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/zstd/lib/legacy/zstd_v04.h b/src/zstd/lib/legacy/zstd_v04.h new file mode 100644 index 000000000..15fce0d48 --- /dev/null +++ b/src/zstd/lib/legacy/zstd_v04.h @@ -0,0 +1,142 @@ +/* + * 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 ZSTD_V04_H_91868324769238 +#define ZSTD_V04_H_91868324769238 + +#if defined (__cplusplus) +extern "C" { +#endif + +/* ************************************* +* Includes +***************************************/ +#include <stddef.h> /* size_t */ + + +/* ************************************* +* Simple one-step function +***************************************/ +/** +ZSTDv04_decompress() : decompress ZSTD frames compliant with v0.4.x format + compressedSize : is the exact source size + maxOriginalSize : is the size of the 'dst' buffer, which must be already allocated. + It must be equal or larger than originalSize, otherwise decompression will fail. + return : the number of bytes decompressed into destination buffer (originalSize) + or an errorCode if it fails (which can be tested using ZSTDv01_isError()) +*/ +size_t ZSTDv04_decompress( void* dst, size_t maxOriginalSize, + const void* src, size_t compressedSize); + + /** + ZSTDv04_findFrameSizeInfoLegacy() : get the source length and decompressed bound of a ZSTD frame compliant with v0.4.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 ZSTDv04_findFrameSizeInfoLegacy(const void *src, size_t srcSize, + size_t* cSize, unsigned long long* dBound); + +/** +ZSTDv04_isError() : tells if the result of ZSTDv04_decompress() is an error +*/ +unsigned ZSTDv04_isError(size_t code); + + +/* ************************************* +* Advanced functions +***************************************/ +typedef struct ZSTDv04_Dctx_s ZSTDv04_Dctx; +ZSTDv04_Dctx* ZSTDv04_createDCtx(void); +size_t ZSTDv04_freeDCtx(ZSTDv04_Dctx* dctx); + +size_t ZSTDv04_decompressDCtx(ZSTDv04_Dctx* dctx, + void* dst, size_t maxOriginalSize, + const void* src, size_t compressedSize); + + +/* ************************************* +* Direct Streaming +***************************************/ +size_t ZSTDv04_resetDCtx(ZSTDv04_Dctx* dctx); + +size_t ZSTDv04_nextSrcSizeToDecompress(ZSTDv04_Dctx* dctx); +size_t ZSTDv04_decompressContinue(ZSTDv04_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize); +/** + Use above functions alternatively. + ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue(). + ZSTD_decompressContinue() will use previous data blocks to improve compression if they are located prior to current block. + Result is the number of bytes regenerated within 'dst'. + It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header. +*/ + + +/* ************************************* +* Buffered Streaming +***************************************/ +typedef struct ZBUFFv04_DCtx_s ZBUFFv04_DCtx; +ZBUFFv04_DCtx* ZBUFFv04_createDCtx(void); +size_t ZBUFFv04_freeDCtx(ZBUFFv04_DCtx* dctx); + +size_t ZBUFFv04_decompressInit(ZBUFFv04_DCtx* dctx); +size_t ZBUFFv04_decompressWithDictionary(ZBUFFv04_DCtx* dctx, const void* dict, size_t dictSize); + +size_t ZBUFFv04_decompressContinue(ZBUFFv04_DCtx* dctx, void* dst, size_t* maxDstSizePtr, const void* src, size_t* srcSizePtr); + +/** ************************************************ +* Streaming decompression +* +* A ZBUFF_DCtx object is required to track streaming operation. +* Use ZBUFF_createDCtx() and ZBUFF_freeDCtx() to create/release resources. +* Use ZBUFF_decompressInit() to start a new decompression operation. +* ZBUFF_DCtx objects can be reused multiple times. +* +* Optionally, a reference to a static dictionary can be set, using ZBUFF_decompressWithDictionary() +* It must be the same content as the one set during compression phase. +* Dictionary content must remain accessible during the decompression process. +* +* Use ZBUFF_decompressContinue() repetitively to consume your input. +* *srcSizePtr and *maxDstSizePtr can be any size. +* The function will report how many bytes were read or written by modifying *srcSizePtr and *maxDstSizePtr. +* 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 *maxDstSizePtr) 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 improve latency) +* or 0 when a frame is completely decoded +* or an error code, which can be tested using ZBUFF_isError(). +* +* Hint : recommended buffer sizes (not compulsory) : ZBUFF_recommendedDInSize / ZBUFF_recommendedDOutSize +* output : ZBUFF_recommendedDOutSize==128 KB block size is the internal unit, it ensures it's always possible to write a full block when it's decoded. +* input : ZBUFF_recommendedDInSize==128Kb+3; just follow indications from ZBUFF_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 . +* **************************************************/ +unsigned ZBUFFv04_isError(size_t errorCode); +const char* ZBUFFv04_getErrorName(size_t errorCode); + + +/** The below functions provide recommended buffer sizes for Compression or Decompression operations. +* These sizes are not compulsory, they just tend to offer better latency */ +size_t ZBUFFv04_recommendedDInSize(void); +size_t ZBUFFv04_recommendedDOutSize(void); + + +/* ************************************* +* Prefix - version detection +***************************************/ +#define ZSTDv04_magicNumber 0xFD2FB524 /* v0.4 */ + + +#if defined (__cplusplus) +} +#endif + +#endif /* ZSTD_V04_H_91868324769238 */ |