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#include <tommath.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.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 *
 * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
 */

/* b = -a */
int mp_neg(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

/* $Source: /cvs/libtom/libtommath/bn_mp_neg.c,v $ */
/* $Revision: 1.4 $ */
/* $Date: 2006/12/28 01:25:13 $ */