tommath/bn_mp_copy.c

69 lines
1.3 KiB
C
Raw Normal View History

2004-10-29 18:07:18 -04:00
#include <tommath.h>
#ifdef BN_MP_COPY_C
2003-02-28 11:08:34 -05:00
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
2003-08-04 21:24:44 -04:00
* LibTomMath is a library that provides multiple-precision
2003-02-28 11:08:34 -05:00
* integer arithmetic as well as number theoretic functionality.
*
2003-08-04 21:24:44 -04:00
* The library was designed directly after the MPI library by
2003-02-28 11:08:34 -05:00
* 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.
*
2007-04-18 05:58:18 -04:00
* Tom St Denis, tomstdenis@gmail.com, http://libtom.org
2003-02-28 11:08:34 -05:00
*/
/* copy, b = a */
int
mp_copy (mp_int * a, mp_int * b)
{
2003-02-28 11:09:08 -05:00
int res, n;
2003-02-28 11:08:34 -05:00
/* if dst == src do nothing */
2003-05-29 09:35:26 -04:00
if (a == b) {
2003-02-28 11:08:34 -05:00
return MP_OKAY;
}
/* grow dest */
2003-08-04 21:24:44 -04:00
if (b->alloc < a->used) {
if ((res = mp_grow (b, a->used)) != MP_OKAY) {
return res;
}
2003-02-28 11:08:34 -05:00
}
/* zero b and copy the parameters over */
2003-02-28 11:09:08 -05:00
{
register mp_digit *tmpa, *tmpb;
2003-05-17 08:33:54 -04:00
/* pointer aliases */
2003-08-04 21:24:44 -04:00
/* source */
2003-02-28 11:09:08 -05:00
tmpa = a->dp;
2003-08-04 21:24:44 -04:00
/* destination */
2003-02-28 11:09:08 -05:00
tmpb = b->dp;
/* copy all the digits */
for (n = 0; n < a->used; n++) {
*tmpb++ = *tmpa++;
}
2003-02-28 11:08:34 -05:00
2003-02-28 11:09:08 -05:00
/* clear high digits */
2003-05-17 08:33:54 -04:00
for (; n < b->used; n++) {
2003-02-28 11:09:08 -05:00
*tmpb++ = 0;
}
2003-02-28 11:08:34 -05:00
}
2003-08-04 21:24:44 -04:00
/* copy used count and sign */
2003-05-17 08:33:54 -04:00
b->used = a->used;
b->sign = a->sign;
2003-02-28 11:08:34 -05:00
return MP_OKAY;
}
2004-10-29 18:07:18 -04:00
#endif
2005-08-01 12:37:28 -04:00
/* $Source$ */
/* $Revision$ */
/* $Date$ */