blob: 4a979854b36e6a8aecfb660f4256f28bbc748f7b [file] [log] [blame]
Scott Baker2c1c4822019-10-16 11:02:41 -07001/*
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 ZSTDv05_H
12#define ZSTDv05_H
13
14#if defined (__cplusplus)
15extern "C" {
16#endif
17
18/*-*************************************
19* Dependencies
20***************************************/
21#include <stddef.h> /* size_t */
22#include "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()) */
33size_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 */
46void 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 */
53unsigned ZSTDv05_isError(size_t code); /*!< tells if a `size_t` function result is an error code */
54const char* ZSTDv05_getErrorName(size_t code); /*!< provides readable string for an error code */
55
56
57/* *************************************
58* Explicit memory management
59***************************************/
60/** Decompression context */
61typedef struct ZSTDv05_DCtx_s ZSTDv05_DCtx;
62ZSTDv05_DCtx* ZSTDv05_createDCtx(void);
63size_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()) */
67size_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() */
77size_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***************************/
85typedef enum { ZSTDv05_fast, ZSTDv05_greedy, ZSTDv05_lazy, ZSTDv05_lazy2, ZSTDv05_btlazy2, ZSTDv05_opt, ZSTDv05_btopt } ZSTDv05_strategy;
86typedef 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;
91size_t ZSTDv05_getFrameParams(ZSTDv05_parameters* params, const void* src, size_t srcSize);
92
93size_t ZSTDv05_decompressBegin_usingDict(ZSTDv05_DCtx* dctx, const void* dict, size_t dictSize);
94void ZSTDv05_copyDCtx(ZSTDv05_DCtx* dstDCtx, const ZSTDv05_DCtx* srcDCtx);
95size_t ZSTDv05_nextSrcSizeToDecompress(ZSTDv05_DCtx* dctx);
96size_t ZSTDv05_decompressContinue(ZSTDv05_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
97
98
99/*-***********************
100* ZBUFF API
101*************************/
102typedef struct ZBUFFv05_DCtx_s ZBUFFv05_DCtx;
103ZBUFFv05_DCtx* ZBUFFv05_createDCtx(void);
104size_t ZBUFFv05_freeDCtx(ZBUFFv05_DCtx* dctx);
105
106size_t ZBUFFv05_decompressInit(ZBUFFv05_DCtx* dctx);
107size_t ZBUFFv05_decompressInitDictionary(ZBUFFv05_DCtx* dctx, const void* dict, size_t dictSize);
108
109size_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***************************************/
140unsigned ZBUFFv05_isError(size_t errorCode);
141const 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 */
145size_t ZBUFFv05_recommendedDInSize(void);
146size_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 */