| 1 | /* |
| 2 | * Handling of the int64 and uint64 types. Done in 32-bit integers, |
| 3 | * for (pre-C99) portability. Hopefully once C99 becomes widespread |
| 4 | * we can kiss this lot goodbye... |
| 5 | */ |
| 6 | |
| 7 | #include <assert.h> |
| 8 | #include <string.h> |
| 9 | |
| 10 | #include "int64.h" |
| 11 | |
| 12 | uint64 uint64_div10(uint64 x, int *remainder) |
| 13 | { |
| 14 | uint64 y; |
| 15 | unsigned int rem, r2; |
| 16 | y.hi = x.hi / 10; |
| 17 | y.lo = x.lo / 10; |
| 18 | rem = x.lo % 10; |
| 19 | /* |
| 20 | * Now we have to add in the remainder left over from x.hi. |
| 21 | */ |
| 22 | r2 = x.hi % 10; |
| 23 | y.lo += r2 * 429496729; |
| 24 | rem += r2 * 6; |
| 25 | y.lo += rem / 10; |
| 26 | rem %= 10; |
| 27 | |
| 28 | if (remainder) |
| 29 | *remainder = rem; |
| 30 | return y; |
| 31 | } |
| 32 | |
| 33 | void uint64_decimal(uint64 x, char *buffer) |
| 34 | { |
| 35 | char buf[20]; |
| 36 | int start = 20; |
| 37 | int d; |
| 38 | |
| 39 | do { |
| 40 | x = uint64_div10(x, &d); |
| 41 | assert(start > 0); |
| 42 | buf[--start] = d + '0'; |
| 43 | } while (x.hi || x.lo); |
| 44 | |
| 45 | memcpy(buffer, buf + start, sizeof(buf) - start); |
| 46 | buffer[sizeof(buf) - start] = '\0'; |
| 47 | } |
| 48 | |
| 49 | uint64 uint64_make(unsigned long hi, unsigned long lo) |
| 50 | { |
| 51 | uint64 y; |
| 52 | y.hi = hi & 0xFFFFFFFFU; |
| 53 | y.lo = lo & 0xFFFFFFFFU; |
| 54 | return y; |
| 55 | } |
| 56 | |
| 57 | uint64 uint64_add(uint64 x, uint64 y) |
| 58 | { |
| 59 | x.lo = (x.lo + y.lo) & 0xFFFFFFFFU; |
| 60 | x.hi += y.hi + (x.lo < y.lo ? 1 : 0); |
| 61 | return x; |
| 62 | } |
| 63 | |
| 64 | uint64 uint64_add32(uint64 x, unsigned long y) |
| 65 | { |
| 66 | uint64 yy; |
| 67 | yy.hi = 0; |
| 68 | yy.lo = y; |
| 69 | return uint64_add(x, yy); |
| 70 | } |
| 71 | |
| 72 | int uint64_compare(uint64 x, uint64 y) |
| 73 | { |
| 74 | if (x.hi != y.hi) |
| 75 | return x.hi < y.hi ? -1 : +1; |
| 76 | if (x.lo != y.lo) |
| 77 | return x.lo < y.lo ? -1 : +1; |
| 78 | return 0; |
| 79 | } |
| 80 | |
| 81 | uint64 uint64_subtract(uint64 x, uint64 y) |
| 82 | { |
| 83 | x.lo = (x.lo - y.lo) & 0xFFFFFFFFU; |
| 84 | x.hi = (x.hi - y.hi - (x.lo > (y.lo ^ 0xFFFFFFFFU) ? 1 : 0)) & 0xFFFFFFFFU; |
| 85 | return x; |
| 86 | } |
| 87 | |
| 88 | double uint64_to_double(uint64 x) |
| 89 | { |
| 90 | return (4294967296.0 * x.hi) + (double)x.lo; |
| 91 | } |
| 92 | |
| 93 | uint64 uint64_shift_right(uint64 x, int shift) |
| 94 | { |
| 95 | if (shift < 32) { |
| 96 | x.lo >>= shift; |
| 97 | x.lo |= (x.hi << (32-shift)) & 0xFFFFFFFFU; |
| 98 | x.hi >>= shift; |
| 99 | } else { |
| 100 | x.lo = x.hi >> (shift-32); |
| 101 | x.hi = 0; |
| 102 | } |
| 103 | return x; |
| 104 | } |
| 105 | |
| 106 | uint64 uint64_shift_left(uint64 x, int shift) |
| 107 | { |
| 108 | if (shift < 32) { |
| 109 | x.hi = (x.hi << shift) & 0xFFFFFFFFU; |
| 110 | x.hi |= (x.lo >> (32-shift)); |
| 111 | x.lo = (x.lo << shift) & 0xFFFFFFFFU; |
| 112 | } else { |
| 113 | x.hi = (x.lo << (shift-32)) & 0xFFFFFFFFU; |
| 114 | x.lo = 0; |
| 115 | } |
| 116 | return x; |
| 117 | } |
| 118 | |
| 119 | uint64 uint64_from_decimal(char *str) |
| 120 | { |
| 121 | uint64 ret; |
| 122 | ret.hi = ret.lo = 0; |
| 123 | while (*str >= '0' && *str <= '9') { |
| 124 | ret = uint64_add(uint64_shift_left(ret, 3), |
| 125 | uint64_shift_left(ret, 1)); |
| 126 | ret = uint64_add32(ret, *str - '0'); |
| 127 | str++; |
| 128 | } |
| 129 | return ret; |
| 130 | } |
| 131 | |
| 132 | #ifdef TESTMODE |
| 133 | |
| 134 | #include <stdio.h> |
| 135 | |
| 136 | int main(void) |
| 137 | { |
| 138 | uint64 x, y, z; |
| 139 | char buf[80]; |
| 140 | |
| 141 | x = uint64_make(0x3456789AUL, 0xDEF01234UL); |
| 142 | printf("%08lx.%08lx\n", x.hi, x.lo); |
| 143 | uint64_decimal(x, buf); |
| 144 | printf("%s\n", buf); |
| 145 | |
| 146 | y = uint64_add32(x, 0xFFFFFFFFU); |
| 147 | printf("%08lx.%08lx\n", y.hi, y.lo); |
| 148 | uint64_decimal(y, buf); |
| 149 | printf("%s\n", buf); |
| 150 | |
| 151 | z = uint64_subtract(y, x); |
| 152 | printf("%08lx.%08lx\n", z.hi, z.lo); |
| 153 | uint64_decimal(z, buf); |
| 154 | printf("%s\n", buf); |
| 155 | |
| 156 | z = uint64_subtract(x, y); |
| 157 | printf("%08lx.%08lx\n", z.hi, z.lo); |
| 158 | uint64_decimal(z, buf); |
| 159 | printf("%s\n", buf); |
| 160 | |
| 161 | y = uint64_shift_right(x, 4); |
| 162 | printf("%08lx.%08lx\n", y.hi, y.lo); |
| 163 | |
| 164 | y = uint64_shift_right(x, 36); |
| 165 | printf("%08lx.%08lx\n", y.hi, y.lo); |
| 166 | |
| 167 | y = uint64_shift_left(x, 4); |
| 168 | printf("%08lx.%08lx\n", x.hi, x.lo); |
| 169 | |
| 170 | y = uint64_shift_left(x, 36); |
| 171 | printf("%08lx.%08lx\n", x.hi, x.lo); |
| 172 | |
| 173 | return 0; |
| 174 | } |
| 175 | #endif |