libtommath/bn_mp_and.c
2019-04-07 17:26:31 +02:00

42 lines
845 B
C

#include "tommath_private.h"
#ifdef BN_MP_AND_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
/* AND two ints together */
int mp_and(const mp_int *a, const mp_int *b, mp_int *c)
{
int res, ix, px;
mp_int t;
const mp_int *x;
if (a->used > b->used) {
if ((res = mp_init_copy(&t, a)) != MP_OKAY) {
return res;
}
px = b->used;
x = b;
} else {
if ((res = mp_init_copy(&t, b)) != MP_OKAY) {
return res;
}
px = a->used;
x = a;
}
for (ix = 0; ix < px; ix++) {
t.dp[ix] &= x->dp[ix];
}
/* zero digits above the last from the smallest mp_int */
for (; ix < t.used; ix++) {
t.dp[ix] = 0;
}
mp_clamp(&t);
mp_exch(c, &t);
mp_clear(&t);
return MP_OKAY;
}
#endif