| Dmitry Kasatkin | 7e8dec9 | 2011-11-07 15:16:37 +0200 | [diff] [blame] | 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 | |
| 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 | |
| 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 | } |