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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.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tstdenis82@gmail.com, http://libtom.org
*/
/* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */
int
mp_mod (mp_int * a, 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
/* $Source$ */
/* $Revision$ */
/* $Date$ */
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