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 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/**
37ZSTDv05_getFrameSrcSize() : get the source length of a ZSTD frame
38 compressedSize : The size of the 'src' buffer, at least as large as the frame pointed to by 'src'
39 return : the number of bytes that would be read to decompress this frame
40 or an errorCode if it fails (which can be tested using ZSTDv05_isError())
41*/
42size_t ZSTDv05_findFrameCompressedSize(const void* src, size_t compressedSize);
43
44/* *************************************
45* Helper functions
46***************************************/
47/* Error Management */
48unsigned ZSTDv05_isError(size_t code); /*!< tells if a `size_t` function result is an error code */
49const char* ZSTDv05_getErrorName(size_t code); /*!< provides readable string for an error code */
50
51
52/* *************************************
53* Explicit memory management
54***************************************/
55/** Decompression context */
56typedef struct ZSTDv05_DCtx_s ZSTDv05_DCtx;
57ZSTDv05_DCtx* ZSTDv05_createDCtx(void);
58size_t ZSTDv05_freeDCtx(ZSTDv05_DCtx* dctx); /*!< @return : errorCode */
59
60/** ZSTDv05_decompressDCtx() :
61* Same as ZSTDv05_decompress(), but requires an already allocated ZSTDv05_DCtx (see ZSTDv05_createDCtx()) */
62size_t ZSTDv05_decompressDCtx(ZSTDv05_DCtx* ctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
63
64
65/*-***********************
66* Simple Dictionary API
67*************************/
68/*! ZSTDv05_decompress_usingDict() :
69* Decompression using a pre-defined Dictionary content (see dictBuilder).
70* Dictionary must be identical to the one used during compression, otherwise regenerated data will be corrupted.
71* Note : dict can be NULL, in which case, it's equivalent to ZSTDv05_decompressDCtx() */
72size_t ZSTDv05_decompress_usingDict(ZSTDv05_DCtx* dctx,
73 void* dst, size_t dstCapacity,
74 const void* src, size_t srcSize,
75 const void* dict,size_t dictSize);
76
77/*-************************
78* Advanced Streaming API
79***************************/
80typedef enum { ZSTDv05_fast, ZSTDv05_greedy, ZSTDv05_lazy, ZSTDv05_lazy2, ZSTDv05_btlazy2, ZSTDv05_opt, ZSTDv05_btopt } ZSTDv05_strategy;
81typedef struct {
82 U64 srcSize;
83 U32 windowLog; /* the only useful information to retrieve */
84 U32 contentLog; U32 hashLog; U32 searchLog; U32 searchLength; U32 targetLength; ZSTDv05_strategy strategy;
85} ZSTDv05_parameters;
86size_t ZSTDv05_getFrameParams(ZSTDv05_parameters* params, const void* src, size_t srcSize);
87
88size_t ZSTDv05_decompressBegin_usingDict(ZSTDv05_DCtx* dctx, const void* dict, size_t dictSize);
89void ZSTDv05_copyDCtx(ZSTDv05_DCtx* dstDCtx, const ZSTDv05_DCtx* srcDCtx);
90size_t ZSTDv05_nextSrcSizeToDecompress(ZSTDv05_DCtx* dctx);
91size_t ZSTDv05_decompressContinue(ZSTDv05_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
92
93
94/*-***********************
95* ZBUFF API
96*************************/
97typedef struct ZBUFFv05_DCtx_s ZBUFFv05_DCtx;
98ZBUFFv05_DCtx* ZBUFFv05_createDCtx(void);
99size_t ZBUFFv05_freeDCtx(ZBUFFv05_DCtx* dctx);
100
101size_t ZBUFFv05_decompressInit(ZBUFFv05_DCtx* dctx);
102size_t ZBUFFv05_decompressInitDictionary(ZBUFFv05_DCtx* dctx, const void* dict, size_t dictSize);
103
104size_t ZBUFFv05_decompressContinue(ZBUFFv05_DCtx* dctx,
105 void* dst, size_t* dstCapacityPtr,
106 const void* src, size_t* srcSizePtr);
107
108/*-***************************************************************************
109* Streaming decompression
110*
111* A ZBUFFv05_DCtx object is required to track streaming operations.
112* Use ZBUFFv05_createDCtx() and ZBUFFv05_freeDCtx() to create/release resources.
113* Use ZBUFFv05_decompressInit() to start a new decompression operation,
114* or ZBUFFv05_decompressInitDictionary() if decompression requires a dictionary.
115* Note that ZBUFFv05_DCtx objects can be reused multiple times.
116*
117* Use ZBUFFv05_decompressContinue() repetitively to consume your input.
118* *srcSizePtr and *dstCapacityPtr can be any size.
119* The function will report how many bytes were read or written by modifying *srcSizePtr and *dstCapacityPtr.
120* Note that it may not consume the entire input, in which case it's up to the caller to present remaining input again.
121* The content of @dst will be overwritten (up to *dstCapacityPtr) at each function call, so save its content if it matters or change @dst.
122* @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to help latency)
123* or 0 when a frame is completely decoded
124* or an error code, which can be tested using ZBUFFv05_isError().
125*
126* Hint : recommended buffer sizes (not compulsory) : ZBUFFv05_recommendedDInSize() / ZBUFFv05_recommendedDOutSize()
127* output : ZBUFFv05_recommendedDOutSize==128 KB block size is the internal unit, it ensures it's always possible to write a full block when decoded.
128* input : ZBUFFv05_recommendedDInSize==128Kb+3; just follow indications from ZBUFFv05_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 .
129* *******************************************************************************/
130
131
132/* *************************************
133* Tool functions
134***************************************/
135unsigned ZBUFFv05_isError(size_t errorCode);
136const char* ZBUFFv05_getErrorName(size_t errorCode);
137
138/** Functions below provide recommended buffer sizes for Compression or Decompression operations.
139* These sizes are just hints, and tend to offer better latency */
140size_t ZBUFFv05_recommendedDInSize(void);
141size_t ZBUFFv05_recommendedDOutSize(void);
142
143
144
145/*-*************************************
146* Constants
147***************************************/
148#define ZSTDv05_MAGICNUMBER 0xFD2FB525 /* v0.5 */
149
150
151
152
153#if defined (__cplusplus)
154}
155#endif
156
157#endif /* ZSTDv0505_H */
158