Linux preempt-rt

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## Elixir Cross Referencer

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182``` ``` /* * Keyed 32-bit hash function using TEA in a Davis-Meyer function * H0 = Key * Hi = E Mi(Hi-1) + Hi-1 * * (see Applied Cryptography, 2nd edition, p448). * * Jeremy Fitzhardinge 1998 * * Jeremy has agreed to the contents of reiserfs/README. -Hans * Yura's function is added (04/07/2000) */ // // keyed_hash // yura_hash // r5_hash // #include #include #include #define DELTA 0x9E3779B9 #define FULLROUNDS 10 /* 32 is overkill, 16 is strong crypto */ #define PARTROUNDS 6 /* 6 gets complete mixing */ /* a, b, c, d - data; h0, h1 - accumulated hash */ #define TEACORE(rounds) \ do { \ u32 sum = 0; \ int n = rounds; \ u32 b0, b1; \ \ b0 = h0; \ b1 = h1; \ \ do \ { \ sum += DELTA; \ b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b); \ b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d); \ } while(--n); \ \ h0 += b0; \ h1 += b1; \ } while(0) u32 keyed_hash(const signed char *msg, int len) { u32 k[] = { 0x9464a485, 0x542e1a94, 0x3e846bff, 0xb75bcfc3 }; u32 h0 = k[0], h1 = k[1]; u32 a, b, c, d; u32 pad; int i; // assert(len >= 0 && len < 256); pad = (u32) len | ((u32) len << 8); pad |= pad << 16; while (len >= 16) { a = (u32) msg[0] | (u32) msg[1] << 8 | (u32) msg[2] << 16 | (u32) msg[3] << 24; b = (u32) msg[4] | (u32) msg[5] << 8 | (u32) msg[6] << 16 | (u32) msg[7] << 24; c = (u32) msg[8] | (u32) msg[9] << 8 | (u32) msg[10] << 16 | (u32) msg[11] << 24; d = (u32) msg[12] | (u32) msg[13] << 8 | (u32) msg[14] << 16 | (u32) msg[15] << 24; TEACORE(PARTROUNDS); len -= 16; msg += 16; } if (len >= 12) { a = (u32) msg[0] | (u32) msg[1] << 8 | (u32) msg[2] << 16 | (u32) msg[3] << 24; b = (u32) msg[4] | (u32) msg[5] << 8 | (u32) msg[6] << 16 | (u32) msg[7] << 24; c = (u32) msg[8] | (u32) msg[9] << 8 | (u32) msg[10] << 16 | (u32) msg[11] << 24; d = pad; for (i = 12; i < len; i++) { d <<= 8; d |= msg[i]; } } else if (len >= 8) { a = (u32) msg[0] | (u32) msg[1] << 8 | (u32) msg[2] << 16 | (u32) msg[3] << 24; b = (u32) msg[4] | (u32) msg[5] << 8 | (u32) msg[6] << 16 | (u32) msg[7] << 24; c = d = pad; for (i = 8; i < len; i++) { c <<= 8; c |= msg[i]; } } else if (len >= 4) { a = (u32) msg[0] | (u32) msg[1] << 8 | (u32) msg[2] << 16 | (u32) msg[3] << 24; b = c = d = pad; for (i = 4; i < len; i++) { b <<= 8; b |= msg[i]; } } else { a = b = c = d = pad; for (i = 0; i < len; i++) { a <<= 8; a |= msg[i]; } } TEACORE(FULLROUNDS); /* return 0;*/ return h0 ^ h1; } /* What follows in this file is copyright 2000 by Hans Reiser, and the * licensing of what follows is governed by reiserfs/README */ u32 yura_hash(const signed char *msg, int len) { int j, pow; u32 a, c; int i; for (pow = 1, i = 1; i < len; i++) pow = pow * 10; if (len == 1) a = msg[0] - 48; else a = (msg[0] - 48) * pow; for (i = 1; i < len; i++) { c = msg[i] - 48; for (pow = 1, j = i; j < len - 1; j++) pow = pow * 10; a = a + c * pow; } for (; i < 40; i++) { c = '0' - 48; for (pow = 1, j = i; j < len - 1; j++) pow = pow * 10; a = a + c * pow; } for (; i < 256; i++) { c = i; for (pow = 1, j = i; j < len - 1; j++) pow = pow * 10; a = a + c * pow; } a = a << 7; return a; } u32 r5_hash(const signed char *msg, int len) { u32 a = 0; while (*msg) { a += *msg << 4; a += *msg >> 4; a *= 11; msg++; } return a; } ```