648db22b |
1 | /* |
2 | * Copyright (c) Yann Collet, Meta Platforms, Inc. and affiliates. |
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_V04_H_91868324769238 |
12 | #define ZSTD_V04_H_91868324769238 |
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 | ZSTDv04_decompress() : decompress ZSTD frames compliant with v0.4.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 ZSTDv04_decompress( void* dst, size_t maxOriginalSize, |
36 | const void* src, size_t compressedSize); |
37 | |
38 | /** |
39 | ZSTDv04_findFrameSizeInfoLegacy() : get the source length and decompressed bound of a ZSTD frame compliant with v0.4.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 ZSTDv04_findFrameSizeInfoLegacy(const void *src, size_t srcSize, |
49 | size_t* cSize, unsigned long long* dBound); |
50 | |
51 | /** |
52 | ZSTDv04_isError() : tells if the result of ZSTDv04_decompress() is an error |
53 | */ |
54 | unsigned ZSTDv04_isError(size_t code); |
55 | |
56 | |
57 | /* ************************************* |
58 | * Advanced functions |
59 | ***************************************/ |
60 | typedef struct ZSTDv04_Dctx_s ZSTDv04_Dctx; |
61 | ZSTDv04_Dctx* ZSTDv04_createDCtx(void); |
62 | size_t ZSTDv04_freeDCtx(ZSTDv04_Dctx* dctx); |
63 | |
64 | size_t ZSTDv04_decompressDCtx(ZSTDv04_Dctx* dctx, |
65 | void* dst, size_t maxOriginalSize, |
66 | const void* src, size_t compressedSize); |
67 | |
68 | |
69 | /* ************************************* |
70 | * Direct Streaming |
71 | ***************************************/ |
72 | size_t ZSTDv04_resetDCtx(ZSTDv04_Dctx* dctx); |
73 | |
74 | size_t ZSTDv04_nextSrcSizeToDecompress(ZSTDv04_Dctx* dctx); |
75 | size_t ZSTDv04_decompressContinue(ZSTDv04_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize); |
76 | /** |
77 | Use above functions alternatively. |
78 | ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue(). |
79 | ZSTD_decompressContinue() will use previous data blocks to improve compression if they are located prior to current block. |
80 | Result is the number of bytes regenerated within 'dst'. |
81 | It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header. |
82 | */ |
83 | |
84 | |
85 | /* ************************************* |
86 | * Buffered Streaming |
87 | ***************************************/ |
88 | typedef struct ZBUFFv04_DCtx_s ZBUFFv04_DCtx; |
89 | ZBUFFv04_DCtx* ZBUFFv04_createDCtx(void); |
90 | size_t ZBUFFv04_freeDCtx(ZBUFFv04_DCtx* dctx); |
91 | |
92 | size_t ZBUFFv04_decompressInit(ZBUFFv04_DCtx* dctx); |
93 | size_t ZBUFFv04_decompressWithDictionary(ZBUFFv04_DCtx* dctx, const void* dict, size_t dictSize); |
94 | |
95 | size_t ZBUFFv04_decompressContinue(ZBUFFv04_DCtx* dctx, void* dst, size_t* maxDstSizePtr, const void* src, size_t* srcSizePtr); |
96 | |
97 | /** ************************************************ |
98 | * Streaming decompression |
99 | * |
100 | * A ZBUFF_DCtx object is required to track streaming operation. |
101 | * Use ZBUFF_createDCtx() and ZBUFF_freeDCtx() to create/release resources. |
102 | * Use ZBUFF_decompressInit() to start a new decompression operation. |
103 | * ZBUFF_DCtx objects can be reused multiple times. |
104 | * |
105 | * Optionally, a reference to a static dictionary can be set, using ZBUFF_decompressWithDictionary() |
106 | * It must be the same content as the one set during compression phase. |
107 | * Dictionary content must remain accessible during the decompression process. |
108 | * |
109 | * Use ZBUFF_decompressContinue() repetitively to consume your input. |
110 | * *srcSizePtr and *maxDstSizePtr can be any size. |
111 | * The function will report how many bytes were read or written by modifying *srcSizePtr and *maxDstSizePtr. |
112 | * Note that it may not consume the entire input, in which case it's up to the caller to present remaining input again. |
113 | * The content of dst will be overwritten (up to *maxDstSizePtr) at each function call, so save its content if it matters or change dst. |
114 | * @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to improve latency) |
115 | * or 0 when a frame is completely decoded |
116 | * or an error code, which can be tested using ZBUFF_isError(). |
117 | * |
118 | * Hint : recommended buffer sizes (not compulsory) : ZBUFF_recommendedDInSize / ZBUFF_recommendedDOutSize |
119 | * 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. |
120 | * input : ZBUFF_recommendedDInSize==128Kb+3; just follow indications from ZBUFF_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 . |
121 | * **************************************************/ |
122 | unsigned ZBUFFv04_isError(size_t errorCode); |
123 | const char* ZBUFFv04_getErrorName(size_t errorCode); |
124 | |
125 | |
126 | /** The below functions provide recommended buffer sizes for Compression or Decompression operations. |
127 | * These sizes are not compulsory, they just tend to offer better latency */ |
128 | size_t ZBUFFv04_recommendedDInSize(void); |
129 | size_t ZBUFFv04_recommendedDOutSize(void); |
130 | |
131 | |
132 | /* ************************************* |
133 | * Prefix - version detection |
134 | ***************************************/ |
135 | #define ZSTDv04_magicNumber 0xFD2FB524 /* v0.4 */ |
136 | |
137 | |
138 | #if defined (__cplusplus) |
139 | } |
140 | #endif |
141 | |
142 | #endif /* ZSTD_V04_H_91868324769238 */ |