libtommath/bn_mp_neg.c
2019-02-02 07:39:23 +01:00

38 lines
865 B
C

#include "tommath_private.h"
#ifdef BN_MP_NEG_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
*/
/* b = -a */
int mp_neg(const mp_int *a, mp_int *b)
{
int res;
if (a != b) {
if ((res = mp_copy(a, b)) != MP_OKAY) {
return res;
}
}
if (!IS_ZERO(b)) {
b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS;
} else {
b->sign = MP_ZPOS;
}
return MP_OKAY;
}
#endif
/* ref: $Format:%D$ */
/* git commit: $Format:%H$ */
/* commit time: $Format:%ai$ */