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 ZSTDv06_H
12#define ZSTDv06_H
13
14#if defined (__cplusplus)
15extern "C" {
16#endif
17
18/*====== Dependency ======*/
19#include <stddef.h> /* size_t */
20
21
22/*====== Export for Windows ======*/
23/*!
24* ZSTDv06_DLL_EXPORT :
25* Enable exporting of functions when building a Windows DLL
26*/
27#if defined(_WIN32) && defined(ZSTDv06_DLL_EXPORT) && (ZSTDv06_DLL_EXPORT==1)
28# define ZSTDLIBv06_API __declspec(dllexport)
29#else
30# define ZSTDLIBv06_API
31#endif
32
33
34/* *************************************
35* Simple functions
36***************************************/
37/*! ZSTDv06_decompress() :
38 `compressedSize` : is the _exact_ size of the compressed blob, otherwise decompression will fail.
39 `dstCapacity` must be large enough, equal or larger than originalSize.
40 @return : the number of bytes decompressed into `dst` (<= `dstCapacity`),
41 or an errorCode if it fails (which can be tested using ZSTDv06_isError()) */
42ZSTDLIBv06_API size_t ZSTDv06_decompress( void* dst, size_t dstCapacity,
43 const void* src, size_t compressedSize);
44
45/**
46ZSTDv06_getFrameSrcSize() : get the source length of a ZSTD frame
47 compressedSize : The size of the 'src' buffer, at least as large as the frame pointed to by 'src'
48 return : the number of bytes that would be read to decompress this frame
49 or an errorCode if it fails (which can be tested using ZSTDv06_isError())
50*/
51size_t ZSTDv06_findFrameCompressedSize(const void* src, size_t compressedSize);
52
53/* *************************************
54* Helper functions
55***************************************/
56ZSTDLIBv06_API size_t ZSTDv06_compressBound(size_t srcSize); /*!< maximum compressed size (worst case scenario) */
57
58/* Error Management */
59ZSTDLIBv06_API unsigned ZSTDv06_isError(size_t code); /*!< tells if a `size_t` function result is an error code */
60ZSTDLIBv06_API const char* ZSTDv06_getErrorName(size_t code); /*!< provides readable string for an error code */
61
62
63/* *************************************
64* Explicit memory management
65***************************************/
66/** Decompression context */
67typedef struct ZSTDv06_DCtx_s ZSTDv06_DCtx;
68ZSTDLIBv06_API ZSTDv06_DCtx* ZSTDv06_createDCtx(void);
69ZSTDLIBv06_API size_t ZSTDv06_freeDCtx(ZSTDv06_DCtx* dctx); /*!< @return : errorCode */
70
71/** ZSTDv06_decompressDCtx() :
72* Same as ZSTDv06_decompress(), but requires an already allocated ZSTDv06_DCtx (see ZSTDv06_createDCtx()) */
73ZSTDLIBv06_API size_t ZSTDv06_decompressDCtx(ZSTDv06_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
74
75
76/*-***********************
77* Dictionary API
78*************************/
79/*! ZSTDv06_decompress_usingDict() :
80* Decompression using a pre-defined Dictionary content (see dictBuilder).
81* Dictionary must be identical to the one used during compression, otherwise regenerated data will be corrupted.
82* Note : dict can be NULL, in which case, it's equivalent to ZSTDv06_decompressDCtx() */
83ZSTDLIBv06_API size_t ZSTDv06_decompress_usingDict(ZSTDv06_DCtx* dctx,
84 void* dst, size_t dstCapacity,
85 const void* src, size_t srcSize,
86 const void* dict,size_t dictSize);
87
88
89/*-************************
90* Advanced Streaming API
91***************************/
92struct ZSTDv06_frameParams_s { unsigned long long frameContentSize; unsigned windowLog; };
93typedef struct ZSTDv06_frameParams_s ZSTDv06_frameParams;
94
95ZSTDLIBv06_API size_t ZSTDv06_getFrameParams(ZSTDv06_frameParams* fparamsPtr, const void* src, size_t srcSize); /**< doesn't consume input */
96ZSTDLIBv06_API size_t ZSTDv06_decompressBegin_usingDict(ZSTDv06_DCtx* dctx, const void* dict, size_t dictSize);
97ZSTDLIBv06_API void ZSTDv06_copyDCtx(ZSTDv06_DCtx* dctx, const ZSTDv06_DCtx* preparedDCtx);
98
99ZSTDLIBv06_API size_t ZSTDv06_nextSrcSizeToDecompress(ZSTDv06_DCtx* dctx);
100ZSTDLIBv06_API size_t ZSTDv06_decompressContinue(ZSTDv06_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
101
102
103
104/* *************************************
105* ZBUFF API
106***************************************/
107
108typedef struct ZBUFFv06_DCtx_s ZBUFFv06_DCtx;
109ZSTDLIBv06_API ZBUFFv06_DCtx* ZBUFFv06_createDCtx(void);
110ZSTDLIBv06_API size_t ZBUFFv06_freeDCtx(ZBUFFv06_DCtx* dctx);
111
112ZSTDLIBv06_API size_t ZBUFFv06_decompressInit(ZBUFFv06_DCtx* dctx);
113ZSTDLIBv06_API size_t ZBUFFv06_decompressInitDictionary(ZBUFFv06_DCtx* dctx, const void* dict, size_t dictSize);
114
115ZSTDLIBv06_API size_t ZBUFFv06_decompressContinue(ZBUFFv06_DCtx* dctx,
116 void* dst, size_t* dstCapacityPtr,
117 const void* src, size_t* srcSizePtr);
118
119/*-***************************************************************************
120* Streaming decompression howto
121*
122* A ZBUFFv06_DCtx object is required to track streaming operations.
123* Use ZBUFFv06_createDCtx() and ZBUFFv06_freeDCtx() to create/release resources.
124* Use ZBUFFv06_decompressInit() to start a new decompression operation,
125* or ZBUFFv06_decompressInitDictionary() if decompression requires a dictionary.
126* Note that ZBUFFv06_DCtx objects can be re-init multiple times.
127*
128* Use ZBUFFv06_decompressContinue() repetitively to consume your input.
129* *srcSizePtr and *dstCapacityPtr can be any size.
130* The function will report how many bytes were read or written by modifying *srcSizePtr and *dstCapacityPtr.
131* Note that it may not consume the entire input, in which case it's up to the caller to present remaining input again.
132* The content of `dst` will be overwritten (up to *dstCapacityPtr) at each function call, so save its content if it matters, or change `dst`.
133* @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to help latency),
134* or 0 when a frame is completely decoded,
135* or an error code, which can be tested using ZBUFFv06_isError().
136*
137* Hint : recommended buffer sizes (not compulsory) : ZBUFFv06_recommendedDInSize() and ZBUFFv06_recommendedDOutSize()
138* output : ZBUFFv06_recommendedDOutSize== 128 KB block size is the internal unit, it ensures it's always possible to write a full block when decoded.
139* input : ZBUFFv06_recommendedDInSize == 128KB + 3;
140* just follow indications from ZBUFFv06_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 .
141* *******************************************************************************/
142
143
144/* *************************************
145* Tool functions
146***************************************/
147ZSTDLIBv06_API unsigned ZBUFFv06_isError(size_t errorCode);
148ZSTDLIBv06_API const char* ZBUFFv06_getErrorName(size_t errorCode);
149
150/** Functions below provide recommended buffer sizes for Compression or Decompression operations.
151* These sizes are just hints, they tend to offer better latency */
152ZSTDLIBv06_API size_t ZBUFFv06_recommendedDInSize(void);
153ZSTDLIBv06_API size_t ZBUFFv06_recommendedDOutSize(void);
154
155
156/*-*************************************
157* Constants
158***************************************/
159#define ZSTDv06_MAGICNUMBER 0xFD2FB526 /* v0.6 */
160
161
162
163#if defined (__cplusplus)
164}
165#endif
166
167#endif /* ZSTDv06_BUFFERED_H */
168