The Tor Browser / file comparison
comparison: security/nss/lib/freebl/mpi/utils/gcd.c
security/nss/lib/freebl/mpi/utils/gcd.c
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
equal
deleted
inserted
replaced
| -1:000000000000 | 0:7b50072acf2c |
|---|---|
| 1 /* | |
| 2 * gcd.c | |
| 3 * | |
| 4 * Greatest common divisor | |
| 5 * | |
| 6 * This Source Code Form is subject to the terms of the Mozilla Public | |
| 7 * License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 8 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ | |
| 9 | |
| 10 #include <stdio.h> | |
| 11 #include <stdlib.h> | |
| 12 #include <string.h> | |
| 13 | |
| 14 #include "mpi.h" | |
| 15 | |
| 16 char *g_prog = NULL; | |
| 17 | |
| 18 void print_mp_int(mp_int *mp, FILE *ofp); | |
| 19 | |
| 20 int main(int argc, char *argv[]) | |
| 21 { | |
| 22 mp_int a, b, x, y; | |
| 23 mp_err res; | |
| 24 int ext = 0; | |
| 25 | |
| 26 g_prog = argv[0]; | |
| 27 | |
| 28 if(argc < 3) { | |
| 29 fprintf(stderr, "Usage: %s <a> <b>\n", g_prog); | |
| 30 return 1; | |
| 31 } | |
| 32 | |
| 33 mp_init(&a); mp_read_radix(&a, argv[1], 10); | |
| 34 mp_init(&b); mp_read_radix(&b, argv[2], 10); | |
| 35 | |
| 36 /* If we were called 'xgcd', compute x, y so that g = ax + by */ | |
| 37 if(strcmp(g_prog, "xgcd") == 0) { | |
| 38 ext = 1; | |
| 39 mp_init(&x); mp_init(&y); | |
| 40 } | |
| 41 | |
| 42 if(ext) { | |
| 43 if((res = mp_xgcd(&a, &b, &a, &x, &y)) != MP_OKAY) { | |
| 44 fprintf(stderr, "%s: error: %s\n", g_prog, mp_strerror(res)); | |
| 45 mp_clear(&a); mp_clear(&b); | |
| 46 mp_clear(&x); mp_clear(&y); | |
| 47 return 1; | |
| 48 } | |
| 49 } else { | |
| 50 if((res = mp_gcd(&a, &b, &a)) != MP_OKAY) { | |
| 51 fprintf(stderr, "%s: error: %s\n", g_prog, | |
| 52 mp_strerror(res)); | |
| 53 mp_clear(&a); mp_clear(&b); | |
| 54 return 1; | |
| 55 } | |
| 56 } | |
| 57 | |
| 58 print_mp_int(&a, stdout); | |
| 59 if(ext) { | |
| 60 fputs("x = ", stdout); print_mp_int(&x, stdout); | |
| 61 fputs("y = ", stdout); print_mp_int(&y, stdout); | |
| 62 } | |
| 63 | |
| 64 mp_clear(&a); mp_clear(&b); | |
| 65 | |
| 66 if(ext) { | |
| 67 mp_clear(&x); | |
| 68 mp_clear(&y); | |
| 69 } | |
| 70 | |
| 71 return 0; | |
| 72 | |
| 73 } | |
| 74 | |
| 75 void print_mp_int(mp_int *mp, FILE *ofp) | |
| 76 { | |
| 77 char *buf; | |
| 78 int len; | |
| 79 | |
| 80 len = mp_radix_size(mp, 10); | |
| 81 buf = calloc(len, sizeof(char)); | |
| 82 mp_todecimal(mp, buf); | |
| 83 fprintf(ofp, "%s\n", buf); | |
| 84 free(buf); | |
| 85 | |
| 86 } |
