view libtommath/bn_mp_neg.c @ 1673:e0871128e61f

CBC mode cleanup (#95) * Fix CBC mode can't be fully disabled * Fix CBC mode can't be the only mode
author Vladislav Grishenko <themiron@users.noreply.github.com>
date Mon, 25 May 2020 20:55:13 +0500
parents f52919ffd3b1
children 1051e4eea25a
line wrap: on
line source

#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 (mp_iszero(b) != MP_YES) {
      b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS;
   } else {
      b->sign = MP_ZPOS;
   }

   return MP_OKAY;
}
#endif

/* ref:         HEAD -> master, tag: v1.1.0 */
/* git commit:  08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
/* commit time: 2019-01-28 20:32:32 +0100 */