363f488d |
1 | /* -*-c-*- |
2 | * |
f51b6004 |
3 | * $Id: primorial.c,v 1.4 2000/08/15 21:41:09 mdw Exp $ |
363f488d |
4 | * |
5 | * Computes the product of the small primes |
6 | * |
7 | * (c) 1999 Straylight/Edgeware |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of Catacomb. |
13 | * |
14 | * Catacomb is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU Library General Public License as |
16 | * published by the Free Software Foundation; either version 2 of the |
17 | * License, or (at your option) any later version. |
18 | * |
19 | * Catacomb is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU Library General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU Library General Public |
25 | * License along with Catacomb; if not, write to the Free |
26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
27 | * MA 02111-1307, USA. |
28 | */ |
29 | |
30 | /*----- Revision history --------------------------------------------------* |
31 | * |
32 | * $Log: primorial.c,v $ |
f51b6004 |
33 | * Revision 1.4 2000/08/15 21:41:09 mdw |
34 | * Bug fix: minimize the right thing. |
35 | * |
1b5b5d69 |
36 | * Revision 1.3 2000/07/15 10:02:07 mdw |
37 | * Include missing header file. |
38 | * |
3edff102 |
39 | * Revision 1.2 2000/07/09 21:31:43 mdw |
40 | * Use `mpmul'. |
41 | * |
363f488d |
42 | * Revision 1.1 1999/12/22 15:51:02 mdw |
43 | * Calculate product of small primes for DSA prime search. |
44 | * |
45 | */ |
46 | |
47 | /*----- Header files ------------------------------------------------------*/ |
48 | |
49 | #include "mp.h" |
1b5b5d69 |
50 | #include "mpint.h" |
3edff102 |
51 | #include "mpmul.h" |
363f488d |
52 | #include "primetab.h" |
53 | |
54 | /*----- Global variables --------------------------------------------------*/ |
55 | |
56 | mp *primorial = 0; |
57 | |
58 | /*----- Main code ---------------------------------------------------------*/ |
59 | |
60 | /* --- @primorial_setup@ --- * |
61 | * |
62 | * Arguments: --- |
63 | * |
64 | * Returns: --- |
65 | * |
66 | * Use: Computes the product of the small primes in the table |
67 | * @primetab@. |
68 | */ |
69 | |
70 | void primorial_setup(void) |
71 | { |
3edff102 |
72 | mp *p = MP_NEW; |
73 | mpmul mm = MPMUL_INIT; |
363f488d |
74 | int i; |
75 | |
76 | if (primorial) |
77 | return; |
3edff102 |
78 | |
363f488d |
79 | for (i = 0; i < NPRIME; i++) { |
3edff102 |
80 | p = mp_fromuint(p, primetab[i]); |
81 | mpmul_add(&mm, p); |
363f488d |
82 | } |
3edff102 |
83 | mp_drop(p); |
84 | primorial = mpmul_done(&mm); |
f51b6004 |
85 | mp_minimize(primorial); |
86 | primorial->a->n--; /* Permanent allocation */ |
363f488d |
87 | } |
88 | |
89 | /*----- That's all, folks -------------------------------------------------*/ |