1/* mpi-cmp.c  -  MPI functions
 2 * Copyright (C) 1998, 1999 Free Software Foundation, Inc.
 3 *
 4 * This file is part of GnuPG.
 5 *
 6 * GnuPG is free software; you can redistribute it and/or modify
 7 * it under the terms of the GNU General Public License as published by
 8 * the Free Software Foundation; either version 2 of the License, or
 9 * (at your option) any later version.
10 *
11 * GnuPG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
19 */
20
21#include "mpi-internal.h"
22
23int mpi_cmp_ui(MPI u, unsigned long v)
24{
25	mpi_limb_t limb = v;
26
27	mpi_normalize(u);
28	if (u->nlimbs == 0) {
29		if (v == 0)
30			return 0;
31		else
32			return -1;
33	}
34	if (u->sign)
35		return -1;
36	if (u->nlimbs > 1)
37		return 1;
38
39	if (u->d[0] == limb)
40		return 0;
41	else if (u->d[0] > limb)
42		return 1;
43	else
44		return -1;
45}
46EXPORT_SYMBOL_GPL(mpi_cmp_ui);
47
48int mpi_cmp(MPI u, MPI v)
49{
50	mpi_size_t usize, vsize;
51	int cmp;
52
53	mpi_normalize(u);
54	mpi_normalize(v);
55	usize = u->nlimbs;
56	vsize = v->nlimbs;
57	if (!u->sign && v->sign)
58		return 1;
59	if (u->sign && !v->sign)
60		return -1;
61	if (usize != vsize && !u->sign && !v->sign)
62		return usize - vsize;
63	if (usize != vsize && u->sign && v->sign)
64		return vsize - usize;
65	if (!usize)
66		return 0;
67	cmp = mpihelp_cmp(u->d, v->d, usize);
68	if (u->sign)
69		return -cmp;
70	return cmp;
71}
72EXPORT_SYMBOL_GPL(mpi_cmp);