projects / thirdparty / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 12f008b6 DH |
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 | EXPORT_SYMBOL_GPL(mpi_cmp_ui); | |
| 43 | ||
| a8ea8bdd | 44 | static int do_mpi_cmp(MPI u, MPI v, int absmode) |
| 12f008b6 | 45 | { |
| a8ea8bdd TZ |
46 | mpi_size_t usize; |
| 47 | mpi_size_t vsize; | |
| 48 | int usign; | |
| 49 | int vsign; | |
| 12f008b6 DH |
50 | int cmp; |
| 51 | ||
| 52 | mpi_normalize(u); | |
| 53 | mpi_normalize(v); | |
| a8ea8bdd | 54 | |
| 12f008b6 DH |
55 | usize = u->nlimbs; |
| 56 | vsize = v->nlimbs; | |
| a8ea8bdd TZ |
57 | usign = absmode ? 0 : u->sign; |
| 58 | vsign = absmode ? 0 : v->sign; | |
| 59 | ||
| 60 | /* Compare sign bits. */ | |
| 61 | ||
| 62 | if (!usign && vsign) | |
| 12f008b6 | 63 | return 1; |
| a8ea8bdd | 64 | if (usign && !vsign) |
| 12f008b6 | 65 | return -1; |
| a8ea8bdd TZ |
66 | |
| 67 | /* U and V are either both positive or both negative. */ | |
| 68 | ||
| 69 | if (usize != vsize && !usign && !vsign) | |
| 12f008b6 | 70 | return usize - vsize; |
| a8ea8bdd TZ |
71 | if (usize != vsize && usign && vsign) |
| 72 | return vsize + usize; | |
| 12f008b6 DH |
73 | if (!usize) |
| 74 | return 0; | |
| 75 | cmp = mpihelp_cmp(u->d, v->d, usize); | |
| a8ea8bdd TZ |
76 | if (!cmp) |
| 77 | return 0; | |
| 78 | if ((cmp < 0?1:0) == (usign?1:0)) | |
| 79 | return 1; | |
| 80 | ||
| 81 | return -1; | |
| 82 | } | |
| 83 | ||
| 84 | int mpi_cmp(MPI u, MPI v) | |
| 85 | { | |
| 86 | return do_mpi_cmp(u, v, 0); | |
| 12f008b6 DH |
87 | } |
| 88 | EXPORT_SYMBOL_GPL(mpi_cmp); | |
| a8ea8bdd TZ |
89 | |
| 90 | int mpi_cmpabs(MPI u, MPI v) | |
| 91 | { | |
| 92 | return do_mpi_cmp(u, v, 1); | |
| 93 | } | |
| 94 | EXPORT_SYMBOL_GPL(mpi_cmpabs); |