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 ZSTDv05_H |
12 | #define ZSTDv05_H |
13 | |
14 | #if defined (__cplusplus) |
15 | extern "C" { |
16 | #endif |
17 | |
18 | /*-************************************* |
19 | * Dependencies |
20 | ***************************************/ |
21 | #include <stddef.h> /* size_t */ |
22 | #include "../common/mem.h" /* U64, U32 */ |
23 | |
24 | |
25 | /* ************************************* |
26 | * Simple functions |
27 | ***************************************/ |
28 | /*! ZSTDv05_decompress() : |
29 | `compressedSize` : is the _exact_ size of the compressed blob, otherwise decompression will fail. |
30 | `dstCapacity` must be large enough, equal or larger than originalSize. |
31 | @return : the number of bytes decompressed into `dst` (<= `dstCapacity`), |
32 | or an errorCode if it fails (which can be tested using ZSTDv05_isError()) */ |
33 | size_t ZSTDv05_decompress( void* dst, size_t dstCapacity, |
34 | const void* src, size_t compressedSize); |
35 | |
36 | /** |
37 | ZSTDv05_findFrameSizeInfoLegacy() : get the source length and decompressed bound of a ZSTD frame compliant with v0.5.x format |
38 | srcSize : The size of the 'src' buffer, at least as large as the frame pointed to by 'src' |
39 | cSize (output parameter) : the number of bytes that would be read to decompress this frame |
40 | or an error code if it fails (which can be tested using ZSTDv01_isError()) |
41 | dBound (output parameter) : an upper-bound for the decompressed size of the data in the frame |
42 | or ZSTD_CONTENTSIZE_ERROR if an error occurs |
43 | |
44 | note : assumes `cSize` and `dBound` are _not_ NULL. |
45 | */ |
46 | void ZSTDv05_findFrameSizeInfoLegacy(const void *src, size_t srcSize, |
47 | size_t* cSize, unsigned long long* dBound); |
48 | |
49 | /* ************************************* |
50 | * Helper functions |
51 | ***************************************/ |
52 | /* Error Management */ |
53 | unsigned ZSTDv05_isError(size_t code); /*!< tells if a `size_t` function result is an error code */ |
54 | const char* ZSTDv05_getErrorName(size_t code); /*!< provides readable string for an error code */ |
55 | |
56 | |
57 | /* ************************************* |
58 | * Explicit memory management |
59 | ***************************************/ |
60 | /** Decompression context */ |
61 | typedef struct ZSTDv05_DCtx_s ZSTDv05_DCtx; |
62 | ZSTDv05_DCtx* ZSTDv05_createDCtx(void); |
63 | size_t ZSTDv05_freeDCtx(ZSTDv05_DCtx* dctx); /*!< @return : errorCode */ |
64 | |
65 | /** ZSTDv05_decompressDCtx() : |
66 | * Same as ZSTDv05_decompress(), but requires an already allocated ZSTDv05_DCtx (see ZSTDv05_createDCtx()) */ |
67 | size_t ZSTDv05_decompressDCtx(ZSTDv05_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); |
68 | |
69 | |
70 | /*-*********************** |
71 | * Simple Dictionary API |
72 | *************************/ |
73 | /*! ZSTDv05_decompress_usingDict() : |
74 | * Decompression using a pre-defined Dictionary content (see dictBuilder). |
75 | * Dictionary must be identical to the one used during compression, otherwise regenerated data will be corrupted. |
76 | * Note : dict can be NULL, in which case, it's equivalent to ZSTDv05_decompressDCtx() */ |
77 | size_t ZSTDv05_decompress_usingDict(ZSTDv05_DCtx* dctx, |
78 | void* dst, size_t dstCapacity, |
79 | const void* src, size_t srcSize, |
80 | const void* dict,size_t dictSize); |
81 | |
82 | /*-************************ |
83 | * Advanced Streaming API |
84 | ***************************/ |
85 | typedef enum { ZSTDv05_fast, ZSTDv05_greedy, ZSTDv05_lazy, ZSTDv05_lazy2, ZSTDv05_btlazy2, ZSTDv05_opt, ZSTDv05_btopt } ZSTDv05_strategy; |
86 | typedef struct { |
87 | U64 srcSize; |
88 | U32 windowLog; /* the only useful information to retrieve */ |
89 | U32 contentLog; U32 hashLog; U32 searchLog; U32 searchLength; U32 targetLength; ZSTDv05_strategy strategy; |
90 | } ZSTDv05_parameters; |
91 | size_t ZSTDv05_getFrameParams(ZSTDv05_parameters* params, const void* src, size_t srcSize); |
92 | |
93 | size_t ZSTDv05_decompressBegin_usingDict(ZSTDv05_DCtx* dctx, const void* dict, size_t dictSize); |
94 | void ZSTDv05_copyDCtx(ZSTDv05_DCtx* dstDCtx, const ZSTDv05_DCtx* srcDCtx); |
95 | size_t ZSTDv05_nextSrcSizeToDecompress(ZSTDv05_DCtx* dctx); |
96 | size_t ZSTDv05_decompressContinue(ZSTDv05_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize); |
97 | |
98 | |
99 | /*-*********************** |
100 | * ZBUFF API |
101 | *************************/ |
102 | typedef struct ZBUFFv05_DCtx_s ZBUFFv05_DCtx; |
103 | ZBUFFv05_DCtx* ZBUFFv05_createDCtx(void); |
104 | size_t ZBUFFv05_freeDCtx(ZBUFFv05_DCtx* dctx); |
105 | |
106 | size_t ZBUFFv05_decompressInit(ZBUFFv05_DCtx* dctx); |
107 | size_t ZBUFFv05_decompressInitDictionary(ZBUFFv05_DCtx* dctx, const void* dict, size_t dictSize); |
108 | |
109 | size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* dctx, |
110 | void* dst, size_t* dstCapacityPtr, |
111 | const void* src, size_t* srcSizePtr); |
112 | |
113 | /*-*************************************************************************** |
114 | * Streaming decompression |
115 | * |
116 | * A ZBUFFv05_DCtx object is required to track streaming operations. |
117 | * Use ZBUFFv05_createDCtx() and ZBUFFv05_freeDCtx() to create/release resources. |
118 | * Use ZBUFFv05_decompressInit() to start a new decompression operation, |
119 | * or ZBUFFv05_decompressInitDictionary() if decompression requires a dictionary. |
120 | * Note that ZBUFFv05_DCtx objects can be reused multiple times. |
121 | * |
122 | * Use ZBUFFv05_decompressContinue() repetitively to consume your input. |
123 | * *srcSizePtr and *dstCapacityPtr can be any size. |
124 | * The function will report how many bytes were read or written by modifying *srcSizePtr and *dstCapacityPtr. |
125 | * Note that it may not consume the entire input, in which case it's up to the caller to present remaining input again. |
126 | * The content of @dst will be overwritten (up to *dstCapacityPtr) at each function call, so save its content if it matters or change @dst. |
127 | * @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to help latency) |
128 | * or 0 when a frame is completely decoded |
129 | * or an error code, which can be tested using ZBUFFv05_isError(). |
130 | * |
131 | * Hint : recommended buffer sizes (not compulsory) : ZBUFFv05_recommendedDInSize() / ZBUFFv05_recommendedDOutSize() |
132 | * output : ZBUFFv05_recommendedDOutSize==128 KB block size is the internal unit, it ensures it's always possible to write a full block when decoded. |
133 | * input : ZBUFFv05_recommendedDInSize==128Kb+3; just follow indications from ZBUFFv05_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 . |
134 | * *******************************************************************************/ |
135 | |
136 | |
137 | /* ************************************* |
138 | * Tool functions |
139 | ***************************************/ |
140 | unsigned ZBUFFv05_isError(size_t errorCode); |
141 | const char* ZBUFFv05_getErrorName(size_t errorCode); |
142 | |
143 | /** Functions below provide recommended buffer sizes for Compression or Decompression operations. |
144 | * These sizes are just hints, and tend to offer better latency */ |
145 | size_t ZBUFFv05_recommendedDInSize(void); |
146 | size_t ZBUFFv05_recommendedDOutSize(void); |
147 | |
148 | |
149 | |
150 | /*-************************************* |
151 | * Constants |
152 | ***************************************/ |
153 | #define ZSTDv05_MAGICNUMBER 0xFD2FB525 /* v0.5 */ |
154 | |
155 | |
156 | |
157 | |
158 | #if defined (__cplusplus) |
159 | } |
160 | #endif |
161 | |
162 | #endif /* ZSTDv0505_H */ |