crypto/external/bsd/heimdal/dist/lib/hcrypto/libtommath/bn_mp_neg.c

   1 /*      $NetBSD: bn_mp_neg.c,v 1.1.1.2 2014/04/24 12:45:31 pettai Exp $ */
   2
   3 #include <tommath.h>
   4 #ifdef BN_MP_NEG_C
   5 /* LibTomMath, multiple-precision integer library -- Tom St Denis
   6  *
   7  * LibTomMath is a library that provides multiple-precision
   8  * integer arithmetic as well as number theoretic functionality.
   9  *
  10  * The library was designed directly after the MPI library by
  11  * Michael Fromberger but has been written from scratch with
  12  * additional optimizations in place.
  13  *
  14  * The library is free for all purposes without any express
  15  * guarantee it works.
  16  *
  17  * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
  18  */
  19
  20 /* b = -a */
  21 int mp_neg (mp_int * a, mp_int * b)
  22 {
  23   int     res;
  24   if (a != b) {
  25      if ((res = mp_copy (a, b)) != MP_OKAY) {
  26         return res;
  27      }
  28   }
  29
  30   if (mp_iszero(b) != MP_YES) {
  31      b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS;
  32   } else {
  33      b->sign = MP_ZPOS;
  34   }
  35
  36   return MP_OKAY;
  37 }
  38 #endif
  39
  40 /* Source: /cvs/libtom/libtommath/bn_mp_neg.c,v  */
  41 /* Revision: 1.4  */
  42 /* Date: 2006/12/28 01:25:13  */