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