ds5w.dscrc32 source code

1 /*
2 	DS_CRC32.h is part of DualSenseWindows
3 	https://github.com/Ohjurot/DualSense-Windows
4 
5 	Contributors of this file:
6 	11.2020 Ludwig Füchsl
7 
8 	Licensed under the MIT License (To be found in repository root directory)
9 */
10 module ds5w.dscrc32;
11 
12 class CRC32
13 {
14 private:
15     /// <summary>
16     /// Fast lookup precalculated byte crc hashes
17     /// </summary>
18     const static uint[256] hashTable =
19         [
20             0xd202ef8d, 0xa505df1b, 0x3c0c8ea1, 0x4b0bbe37, 0xd56f2b94, 0xa2681b02,
21             0x3b614ab8, 0x4c667a2e,
22             0xdcd967bf, 0xabde5729, 0x32d70693, 0x45d03605, 0xdbb4a3a6, 0xacb39330,
23             0x35bac28a, 0x42bdf21c,
24             0xcfb5ffe9, 0xb8b2cf7f, 0x21bb9ec5, 0x56bcae53, 0xc8d83bf0, 0xbfdf0b66,
25             0x26d65adc, 0x51d16a4a,
26             0xc16e77db, 0xb669474d, 0x2f6016f7, 0x58672661, 0xc603b3c2, 0xb1048354,
27             0x280dd2ee, 0x5f0ae278,
28             0xe96ccf45, 0x9e6bffd3, 0x762ae69, 0x70659eff, 0xee010b5c, 0x99063bca,
29             0xf6a70, 0x77085ae6,
30             0xe7b74777, 0x90b077e1, 0x9b9265b, 0x7ebe16cd, 0xe0da836e, 0x97ddb3f8,
31             0xed4e242, 0x79d3d2d4,
32             0xf4dbdf21, 0x83dcefb7, 0x1ad5be0d, 0x6dd28e9b, 0xf3b61b38, 0x84b12bae,
33             0x1db87a14, 0x6abf4a82,
34             0xfa005713, 0x8d076785, 0x140e363f, 0x630906a9, 0xfd6d930a, 0x8a6aa39c,
35             0x1363f226, 0x6464c2b0,
36             0xa4deae1d, 0xd3d99e8b, 0x4ad0cf31, 0x3dd7ffa7, 0xa3b36a04, 0xd4b45a92,
37             0x4dbd0b28, 0x3aba3bbe,
38             0xaa05262f, 0xdd0216b9, 0x440b4703, 0x330c7795, 0xad68e236, 0xda6fd2a0,
39             0x4366831a, 0x3461b38c,
40             0xb969be79, 0xce6e8eef, 0x5767df55, 0x2060efc3, 0xbe047a60, 0xc9034af6,
41             0x500a1b4c, 0x270d2bda,
42             0xb7b2364b, 0xc0b506dd, 0x59bc5767, 0x2ebb67f1, 0xb0dff252, 0xc7d8c2c4,
43             0x5ed1937e, 0x29d6a3e8,
44             0x9fb08ed5, 0xe8b7be43, 0x71beeff9, 0x6b9df6f, 0x98dd4acc, 0xefda7a5a,
45             0x76d32be0, 0x1d41b76,
46             0x916b06e7, 0xe66c3671, 0x7f6567cb, 0x862575d, 0x9606c2fe, 0xe101f268,
47             0x7808a3d2, 0xf0f9344,
48             0x82079eb1, 0xf500ae27, 0x6c09ff9d, 0x1b0ecf0b, 0x856a5aa8, 0xf26d6a3e,
49             0x6b643b84, 0x1c630b12,
50             0x8cdc1683, 0xfbdb2615, 0x62d277af, 0x15d54739, 0x8bb1d29a, 0xfcb6e20c,
51             0x65bfb3b6, 0x12b88320,
52             0x3fba6cad, 0x48bd5c3b, 0xd1b40d81, 0xa6b33d17, 0x38d7a8b4, 0x4fd09822,
53             0xd6d9c998, 0xa1def90e,
54             0x3161e49f, 0x4666d409, 0xdf6f85b3, 0xa868b525, 0x360c2086, 0x410b1010,
55             0xd80241aa, 0xaf05713c,
56             0x220d7cc9, 0x550a4c5f, 0xcc031de5, 0xbb042d73, 0x2560b8d0, 0x52678846,
57             0xcb6ed9fc, 0xbc69e96a,
58             0x2cd6f4fb, 0x5bd1c46d, 0xc2d895d7, 0xb5dfa541, 0x2bbb30e2, 0x5cbc0074,
59             0xc5b551ce, 0xb2b26158,
60             0x4d44c65, 0x73d37cf3, 0xeada2d49, 0x9ddd1ddf, 0x3b9887c, 0x74beb8ea,
61             0xedb7e950, 0x9ab0d9c6,
62             0xa0fc457, 0x7d08f4c1, 0xe401a57b, 0x930695ed, 0xd62004e, 0x7a6530d8,
63             0xe36c6162, 0x946b51f4,
64             0x19635c01, 0x6e646c97, 0xf76d3d2d, 0x806a0dbb, 0x1e0e9818, 0x6909a88e,
65             0xf000f934, 0x8707c9a2,
66             0x17b8d433, 0x60bfe4a5, 0xf9b6b51f, 0x8eb18589, 0x10d5102a, 0x67d220bc,
67             0xfedb7106, 0x89dc4190,
68             0x49662d3d, 0x3e611dab, 0xa7684c11, 0xd06f7c87, 0x4e0be924, 0x390cd9b2,
69             0xa0058808, 0xd702b89e,
70             0x47bda50f, 0x30ba9599, 0xa9b3c423, 0xdeb4f4b5, 0x40d06116, 0x37d75180,
71             0xaede003a, 0xd9d930ac,
72             0x54d13d59, 0x23d60dcf, 0xbadf5c75, 0xcdd86ce3, 0x53bcf940, 0x24bbc9d6,
73             0xbdb2986c, 0xcab5a8fa,
74             0x5a0ab56b, 0x2d0d85fd, 0xb404d447, 0xc303e4d1, 0x5d677172, 0x2a6041e4,
75             0xb369105e, 0xc46e20c8,
76             0x72080df5, 0x50f3d63, 0x9c066cd9, 0xeb015c4f, 0x7565c9ec, 0x262f97a,
77             0x9b6ba8c0, 0xec6c9856,
78             0x7cd385c7, 0xbd4b551, 0x92dde4eb, 0xe5dad47d, 0x7bbe41de, 0xcb97148,
79             0x95b020f2, 0xe2b71064,
80             0x6fbf1d91, 0x18b82d07, 0x81b17cbd, 0xf6b64c2b, 0x68d2d988, 0x1fd5e91e,
81             0x86dcb8a4, 0xf1db8832,
82             0x616495a3, 0x1663a535, 0x8f6af48f, 0xf86dc419, 0x660951ba, 0x110e612c,
83             0x88073096, 0xff000000
84         ];
85 
86     /// <summary>
87     /// Start seed for crc hash
88     /// </summary>
89     const static uint crcSeed = 0xeada2d49;
90 
91 public:
92     /// <summary>
93     /// Compute the CRC32 Hash
94     /// </summary>
95     /// <param name="buffer">Input buffer</param>
96     /// <param name="len">Length of buffer</param>
97     /// <returns>Computed crc value</returns>
98     static uint compute(ubyte* buffer, int len)
99     {
100         // Start point
101         uint result = crcSeed;
102 
103         // Foreach element in arrray
104         foreach (i; 0 .. len)
105         {
106             // Compute crc
107             result = hashTable[(cast(ubyte) result) ^ (cast(ubyte) buffer[i])] ^ (result >> 8);
108         }
109 
110         // Return result
111         return result;
112     }
113 }