Holger Hildebrandt | fa07499 | 2020-03-27 15:42:06 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This source code is licensed under both the BSD-style license (found in the |
| 6 | * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
| 7 | * in the COPYING file in the root directory of this source tree). |
| 8 | * You may select, at your option, one of the above-listed licenses. |
| 9 | */ |
| 10 | |
| 11 | #ifndef ZSTD_V02_H_4174539423 |
| 12 | #define ZSTD_V02_H_4174539423 |
| 13 | |
| 14 | #if defined (__cplusplus) |
| 15 | extern "C" { |
| 16 | #endif |
| 17 | |
| 18 | /* ************************************* |
| 19 | * Includes |
| 20 | ***************************************/ |
| 21 | #include <stddef.h> /* size_t */ |
| 22 | |
| 23 | |
| 24 | /* ************************************* |
| 25 | * Simple one-step function |
| 26 | ***************************************/ |
| 27 | /** |
| 28 | ZSTDv02_decompress() : decompress ZSTD frames compliant with v0.2.x format |
| 29 | compressedSize : is the exact source size |
| 30 | maxOriginalSize : is the size of the 'dst' buffer, which must be already allocated. |
| 31 | It must be equal or larger than originalSize, otherwise decompression will fail. |
| 32 | return : the number of bytes decompressed into destination buffer (originalSize) |
| 33 | or an errorCode if it fails (which can be tested using ZSTDv01_isError()) |
| 34 | */ |
| 35 | size_t ZSTDv02_decompress( void* dst, size_t maxOriginalSize, |
| 36 | const void* src, size_t compressedSize); |
| 37 | |
| 38 | /** |
| 39 | ZSTDv02_findFrameSizeInfoLegacy() : get the source length and decompressed bound of a ZSTD frame compliant with v0.2.x format |
| 40 | srcSize : The size of the 'src' buffer, at least as large as the frame pointed to by 'src' |
| 41 | cSize (output parameter) : the number of bytes that would be read to decompress this frame |
| 42 | or an error code if it fails (which can be tested using ZSTDv01_isError()) |
| 43 | dBound (output parameter) : an upper-bound for the decompressed size of the data in the frame |
| 44 | or ZSTD_CONTENTSIZE_ERROR if an error occurs |
| 45 | |
| 46 | note : assumes `cSize` and `dBound` are _not_ NULL. |
| 47 | */ |
| 48 | void ZSTDv02_findFrameSizeInfoLegacy(const void *src, size_t srcSize, |
| 49 | size_t* cSize, unsigned long long* dBound); |
| 50 | |
| 51 | /** |
| 52 | ZSTDv02_isError() : tells if the result of ZSTDv02_decompress() is an error |
| 53 | */ |
| 54 | unsigned ZSTDv02_isError(size_t code); |
| 55 | |
| 56 | |
| 57 | /* ************************************* |
| 58 | * Advanced functions |
| 59 | ***************************************/ |
| 60 | typedef struct ZSTDv02_Dctx_s ZSTDv02_Dctx; |
| 61 | ZSTDv02_Dctx* ZSTDv02_createDCtx(void); |
| 62 | size_t ZSTDv02_freeDCtx(ZSTDv02_Dctx* dctx); |
| 63 | |
| 64 | size_t ZSTDv02_decompressDCtx(void* ctx, |
| 65 | void* dst, size_t maxOriginalSize, |
| 66 | const void* src, size_t compressedSize); |
| 67 | |
| 68 | /* ************************************* |
| 69 | * Streaming functions |
| 70 | ***************************************/ |
| 71 | size_t ZSTDv02_resetDCtx(ZSTDv02_Dctx* dctx); |
| 72 | |
| 73 | size_t ZSTDv02_nextSrcSizeToDecompress(ZSTDv02_Dctx* dctx); |
| 74 | size_t ZSTDv02_decompressContinue(ZSTDv02_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize); |
| 75 | /** |
| 76 | Use above functions alternatively. |
| 77 | ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue(). |
| 78 | ZSTD_decompressContinue() will use previous data blocks to improve compression if they are located prior to current block. |
| 79 | Result is the number of bytes regenerated within 'dst'. |
| 80 | It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header. |
| 81 | */ |
| 82 | |
| 83 | /* ************************************* |
| 84 | * Prefix - version detection |
| 85 | ***************************************/ |
| 86 | #define ZSTDv02_magicNumber 0xFD2FB522 /* v0.2 */ |
| 87 | |
| 88 | |
| 89 | #if defined (__cplusplus) |
| 90 | } |
| 91 | #endif |
| 92 | |
| 93 | #endif /* ZSTD_V02_H_4174539423 */ |