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
mpi_cmp_ui(MPI u,unsigned long v)23 int mpi_cmp_ui(MPI u, unsigned long v)
24 {
25 mpi_limb_t limb = v;
26
27 mpi_normalize(u);
28 if (!u->nlimbs && !limb)
29 return 0;
30 if (u->sign)
31 return -1;
32 if (u->nlimbs > 1)
33 return 1;
34
35 if (u->d[0] == limb)
36 return 0;
37 else if (u->d[0] > limb)
38 return 1;
39 else
40 return -1;
41 }
42
mpi_cmp(MPI u,MPI v)43 int mpi_cmp(MPI u, MPI v)
44 {
45 mpi_size_t usize, vsize;
46 int cmp;
47
48 mpi_normalize(u);
49 mpi_normalize(v);
50 usize = u->nlimbs;
51 vsize = v->nlimbs;
52 if (!u->sign && v->sign)
53 return 1;
54 if (u->sign && !v->sign)
55 return -1;
56 if (usize != vsize && !u->sign && !v->sign)
57 return usize - vsize;
58 if (usize != vsize && u->sign && v->sign)
59 return vsize + usize;
60 if (!usize)
61 return 0;
62 cmp = mpihelp_cmp(u->d, v->d, usize);
63 if (!cmp)
64 return 0;
65 if ((cmp < 0 ? 1 : 0) == (u->sign ? 1 : 0))
66 return 1;
67 return -1;
68 }
69