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#include <tommath.h>
#ifdef BN_MP_COPY_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
 */

/* copy, b = a */
int mp_copy(mp_int * a, mp_int * b)
{
	int res, n;

	/* if dst == src do nothing */
	if (a == b) {
		return MP_OKAY;
	}

	/* grow dest */
	if (b->alloc < a->used) {
		if ((res = mp_grow(b, a->used)) != MP_OKAY) {
			return res;
		}
	}

	/* zero b and copy the parameters over */
	{
		register mp_digit *tmpa, *tmpb;

		/* pointer aliases */

		/* source */
		tmpa = a->dp;

		/* destination */
		tmpb = b->dp;

		/* copy all the digits */
		for (n = 0; n < a->used; n++) {
			*tmpb++ = *tmpa++;
		}

		/* clear high digits */
		for (; n < b->used; n++) {
			*tmpb++ = 0;
		}
	}

	/* copy used count and sign */
	b->used = a->used;
	b->sign = a->sign;
	return MP_OKAY;
}
#endif

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