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#include "tommath_private.h"
#ifdef BN_MP_MOD_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
* LibTomMath is a library that provides multiple-precision
* integer arithmetic as well as number theoretic functionality.
*
* The library was designed directly after the MPI library by
* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
* SPDX-License-Identifier: Unlicense
*/
/* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */
int mp_mod(const mp_int *a, const mp_int *b, mp_int *c)
{
mp_int t;
int res;
if ((res = mp_init_size(&t, b->used)) != MP_OKAY) {
return res;
}
if ((res = mp_div(a, b, NULL, &t)) != MP_OKAY) {
mp_clear(&t);
return res;
}
if ((mp_iszero(&t) != MP_NO) || (t.sign == b->sign)) {
res = MP_OKAY;
mp_exch(&t, c);
} else {
res = mp_add(b, &t, c);
}
mp_clear(&t);
return res;
}
#endif
/* ref: $Format:%D$ */
/* git commit: $Format:%H$ */
/* commit time: $Format:%ai$ */
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