xref: /aosp_15_r20/external/zstd/lib/legacy/zstd_v04.h (revision 01826a4963a0d8a59bc3812d29bdf0fb76416722)
1*01826a49SYabin Cui /*
2*01826a49SYabin Cui  * Copyright (c) Yann Collet, Meta Platforms, Inc. and affiliates.
3*01826a49SYabin Cui  * All rights reserved.
4*01826a49SYabin Cui  *
5*01826a49SYabin Cui  * This source code is licensed under both the BSD-style license (found in the
6*01826a49SYabin Cui  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7*01826a49SYabin Cui  * in the COPYING file in the root directory of this source tree).
8*01826a49SYabin Cui  * You may select, at your option, one of the above-listed licenses.
9*01826a49SYabin Cui  */
10*01826a49SYabin Cui 
11*01826a49SYabin Cui #ifndef ZSTD_V04_H_91868324769238
12*01826a49SYabin Cui #define ZSTD_V04_H_91868324769238
13*01826a49SYabin Cui 
14*01826a49SYabin Cui #if defined (__cplusplus)
15*01826a49SYabin Cui extern "C" {
16*01826a49SYabin Cui #endif
17*01826a49SYabin Cui 
18*01826a49SYabin Cui /* *************************************
19*01826a49SYabin Cui *  Includes
20*01826a49SYabin Cui ***************************************/
21*01826a49SYabin Cui #include <stddef.h>   /* size_t */
22*01826a49SYabin Cui 
23*01826a49SYabin Cui 
24*01826a49SYabin Cui /* *************************************
25*01826a49SYabin Cui *  Simple one-step function
26*01826a49SYabin Cui ***************************************/
27*01826a49SYabin Cui /**
28*01826a49SYabin Cui ZSTDv04_decompress() : decompress ZSTD frames compliant with v0.4.x format
29*01826a49SYabin Cui     compressedSize : is the exact source size
30*01826a49SYabin Cui     maxOriginalSize : is the size of the 'dst' buffer, which must be already allocated.
31*01826a49SYabin Cui                       It must be equal or larger than originalSize, otherwise decompression will fail.
32*01826a49SYabin Cui     return : the number of bytes decompressed into destination buffer (originalSize)
33*01826a49SYabin Cui              or an errorCode if it fails (which can be tested using ZSTDv01_isError())
34*01826a49SYabin Cui */
35*01826a49SYabin Cui size_t ZSTDv04_decompress( void* dst, size_t maxOriginalSize,
36*01826a49SYabin Cui                      const void* src, size_t compressedSize);
37*01826a49SYabin Cui 
38*01826a49SYabin Cui  /**
39*01826a49SYabin Cui  ZSTDv04_findFrameSizeInfoLegacy() : get the source length and decompressed bound of a ZSTD frame compliant with v0.4.x format
40*01826a49SYabin Cui      srcSize : The size of the 'src' buffer, at least as large as the frame pointed to by 'src'
41*01826a49SYabin Cui      cSize (output parameter)  : the number of bytes that would be read to decompress this frame
42*01826a49SYabin Cui                                  or an error code if it fails (which can be tested using ZSTDv01_isError())
43*01826a49SYabin Cui      dBound (output parameter) : an upper-bound for the decompressed size of the data in the frame
44*01826a49SYabin Cui                                  or ZSTD_CONTENTSIZE_ERROR if an error occurs
45*01826a49SYabin Cui 
46*01826a49SYabin Cui     note : assumes `cSize` and `dBound` are _not_ NULL.
47*01826a49SYabin Cui  */
48*01826a49SYabin Cui  void ZSTDv04_findFrameSizeInfoLegacy(const void *src, size_t srcSize,
49*01826a49SYabin Cui                                       size_t* cSize, unsigned long long* dBound);
50*01826a49SYabin Cui 
51*01826a49SYabin Cui /**
52*01826a49SYabin Cui ZSTDv04_isError() : tells if the result of ZSTDv04_decompress() is an error
53*01826a49SYabin Cui */
54*01826a49SYabin Cui unsigned ZSTDv04_isError(size_t code);
55*01826a49SYabin Cui 
56*01826a49SYabin Cui 
57*01826a49SYabin Cui /* *************************************
58*01826a49SYabin Cui *  Advanced functions
59*01826a49SYabin Cui ***************************************/
60*01826a49SYabin Cui typedef struct ZSTDv04_Dctx_s ZSTDv04_Dctx;
61*01826a49SYabin Cui ZSTDv04_Dctx* ZSTDv04_createDCtx(void);
62*01826a49SYabin Cui size_t ZSTDv04_freeDCtx(ZSTDv04_Dctx* dctx);
63*01826a49SYabin Cui 
64*01826a49SYabin Cui size_t ZSTDv04_decompressDCtx(ZSTDv04_Dctx* dctx,
65*01826a49SYabin Cui                               void* dst, size_t maxOriginalSize,
66*01826a49SYabin Cui                         const void* src, size_t compressedSize);
67*01826a49SYabin Cui 
68*01826a49SYabin Cui 
69*01826a49SYabin Cui /* *************************************
70*01826a49SYabin Cui *  Direct Streaming
71*01826a49SYabin Cui ***************************************/
72*01826a49SYabin Cui size_t ZSTDv04_resetDCtx(ZSTDv04_Dctx* dctx);
73*01826a49SYabin Cui 
74*01826a49SYabin Cui size_t ZSTDv04_nextSrcSizeToDecompress(ZSTDv04_Dctx* dctx);
75*01826a49SYabin Cui size_t ZSTDv04_decompressContinue(ZSTDv04_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize);
76*01826a49SYabin Cui /**
77*01826a49SYabin Cui   Use above functions alternatively.
78*01826a49SYabin Cui   ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue().
79*01826a49SYabin Cui   ZSTD_decompressContinue() will use previous data blocks to improve compression if they are located prior to current block.
80*01826a49SYabin Cui   Result is the number of bytes regenerated within 'dst'.
81*01826a49SYabin Cui   It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header.
82*01826a49SYabin Cui */
83*01826a49SYabin Cui 
84*01826a49SYabin Cui 
85*01826a49SYabin Cui /* *************************************
86*01826a49SYabin Cui *  Buffered Streaming
87*01826a49SYabin Cui ***************************************/
88*01826a49SYabin Cui typedef struct ZBUFFv04_DCtx_s ZBUFFv04_DCtx;
89*01826a49SYabin Cui ZBUFFv04_DCtx* ZBUFFv04_createDCtx(void);
90*01826a49SYabin Cui size_t         ZBUFFv04_freeDCtx(ZBUFFv04_DCtx* dctx);
91*01826a49SYabin Cui 
92*01826a49SYabin Cui size_t ZBUFFv04_decompressInit(ZBUFFv04_DCtx* dctx);
93*01826a49SYabin Cui size_t ZBUFFv04_decompressWithDictionary(ZBUFFv04_DCtx* dctx, const void* dict, size_t dictSize);
94*01826a49SYabin Cui 
95*01826a49SYabin Cui size_t ZBUFFv04_decompressContinue(ZBUFFv04_DCtx* dctx, void* dst, size_t* maxDstSizePtr, const void* src, size_t* srcSizePtr);
96*01826a49SYabin Cui 
97*01826a49SYabin Cui /** ************************************************
98*01826a49SYabin Cui *  Streaming decompression
99*01826a49SYabin Cui *
100*01826a49SYabin Cui *  A ZBUFF_DCtx object is required to track streaming operation.
101*01826a49SYabin Cui *  Use ZBUFF_createDCtx() and ZBUFF_freeDCtx() to create/release resources.
102*01826a49SYabin Cui *  Use ZBUFF_decompressInit() to start a new decompression operation.
103*01826a49SYabin Cui *  ZBUFF_DCtx objects can be reused multiple times.
104*01826a49SYabin Cui *
105*01826a49SYabin Cui *  Optionally, a reference to a static dictionary can be set, using ZBUFF_decompressWithDictionary()
106*01826a49SYabin Cui *  It must be the same content as the one set during compression phase.
107*01826a49SYabin Cui *  Dictionary content must remain accessible during the decompression process.
108*01826a49SYabin Cui *
109*01826a49SYabin Cui *  Use ZBUFF_decompressContinue() repetitively to consume your input.
110*01826a49SYabin Cui *  *srcSizePtr and *maxDstSizePtr can be any size.
111*01826a49SYabin Cui *  The function will report how many bytes were read or written by modifying *srcSizePtr and *maxDstSizePtr.
112*01826a49SYabin Cui *  Note that it may not consume the entire input, in which case it's up to the caller to present remaining input again.
113*01826a49SYabin Cui *  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*01826a49SYabin Cui *  @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*01826a49SYabin Cui *            or 0 when a frame is completely decoded
116*01826a49SYabin Cui *            or an error code, which can be tested using ZBUFF_isError().
117*01826a49SYabin Cui *
118*01826a49SYabin Cui *  Hint : recommended buffer sizes (not compulsory) : ZBUFF_recommendedDInSize / ZBUFF_recommendedDOutSize
119*01826a49SYabin Cui *  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*01826a49SYabin Cui *  input : ZBUFF_recommendedDInSize==128Kb+3; just follow indications from ZBUFF_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 .
121*01826a49SYabin Cui * **************************************************/
122*01826a49SYabin Cui unsigned ZBUFFv04_isError(size_t errorCode);
123*01826a49SYabin Cui const char* ZBUFFv04_getErrorName(size_t errorCode);
124*01826a49SYabin Cui 
125*01826a49SYabin Cui 
126*01826a49SYabin Cui /** The below functions provide recommended buffer sizes for Compression or Decompression operations.
127*01826a49SYabin Cui *   These sizes are not compulsory, they just tend to offer better latency */
128*01826a49SYabin Cui size_t ZBUFFv04_recommendedDInSize(void);
129*01826a49SYabin Cui size_t ZBUFFv04_recommendedDOutSize(void);
130*01826a49SYabin Cui 
131*01826a49SYabin Cui 
132*01826a49SYabin Cui /* *************************************
133*01826a49SYabin Cui *  Prefix - version detection
134*01826a49SYabin Cui ***************************************/
135*01826a49SYabin Cui #define ZSTDv04_magicNumber 0xFD2FB524   /* v0.4 */
136*01826a49SYabin Cui 
137*01826a49SYabin Cui 
138*01826a49SYabin Cui #if defined (__cplusplus)
139*01826a49SYabin Cui }
140*01826a49SYabin Cui #endif
141*01826a49SYabin Cui 
142*01826a49SYabin Cui #endif /* ZSTD_V04_H_91868324769238 */
143