SDL  2.0
SDL_test_crc32.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 
22 /**
23  * \file SDL_test_crc32.h
24  *
25  * Include file for SDL test framework.
26  *
27  * This code is a part of the SDL2_test library, not the main SDL library.
28  */
29 
30 /*
31 
32  Implements CRC32 calculations (default output is Perl String::CRC32 compatible).
33 
34 */
35 
36 #ifndef SDL_test_crc32_h_
37 #define SDL_test_crc32_h_
38 
39 #include "begin_code.h"
40 /* Set up for C function definitions, even when using C++ */
41 #ifdef __cplusplus
42 extern "C" {
43 #endif
44 
45 
46 /* ------------ Definitions --------- */
47 
48 /* Definition shared by all CRC routines */
49 
50 #ifndef CrcUint32
51  #define CrcUint32 unsigned int
52 #endif
53 #ifndef CrcUint8
54  #define CrcUint8 unsigned char
55 #endif
56 
57 #ifdef ORIGINAL_METHOD
58  #define CRC32_POLY 0x04c11db7 /* AUTODIN II, Ethernet, & FDDI */
59 #else
60  #define CRC32_POLY 0xEDB88320 /* Perl String::CRC32 compatible */
61 #endif
62 
63 /**
64  * Data structure for CRC32 (checksum) computation
65  */
66  typedef struct {
67  CrcUint32 crc32_table[256]; /* CRC table */
68  } SDLTest_Crc32Context;
69 
70 /* ---------- Function Prototypes ------------- */
71 
72 /**
73  * \brief Initialize the CRC context
74  *
75  * Note: The function initializes the crc table required for all crc calculations.
76  *
77  * \param crcContext pointer to context variable
78  *
79  * \returns 0 for OK, -1 on error
80  *
81  */
82  int SDLTest_Crc32Init(SDLTest_Crc32Context * crcContext);
83 
84 
85 /**
86  * \brief calculate a crc32 from a data block
87  *
88  * \param crcContext pointer to context variable
89  * \param inBuf input buffer to checksum
90  * \param inLen length of input buffer
91  * \param crc32 pointer to Uint32 to store the final CRC into
92  *
93  * \returns 0 for OK, -1 on error
94  *
95  */
96 int SDLTest_Crc32Calc(SDLTest_Crc32Context * crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32);
97 
98 /* Same routine broken down into three steps */
99 int SDLTest_Crc32CalcStart(SDLTest_Crc32Context * crcContext, CrcUint32 *crc32);
100 int SDLTest_Crc32CalcEnd(SDLTest_Crc32Context * crcContext, CrcUint32 *crc32);
101 int SDLTest_Crc32CalcBuffer(SDLTest_Crc32Context * crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32);
102 
103 
104 /**
105  * \brief clean up CRC context
106  *
107  * \param crcContext pointer to context variable
108  *
109  * \returns 0 for OK, -1 on error
110  *
111 */
112 
113 int SDLTest_Crc32Done(SDLTest_Crc32Context * crcContext);
114 
115 
116 /* Ends C function definitions when using C++ */
117 #ifdef __cplusplus
118 }
119 #endif
120 #include "close_code.h"
121 
122 #endif /* SDL_test_crc32_h_ */
123 
124 /* vi: set ts=4 sw=4 expandtab: */