Commit | Line | Data |
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893c6259 | 1 | /* -*-c-*- |
2 | * | |
893c6259 | 3 | * Generate a random multiprecision integer |
4 | * | |
5 | * (c) 1999 Straylight/Edgeware | |
6 | */ | |
7 | ||
45c0fd36 | 8 | /*----- Licensing notice --------------------------------------------------* |
893c6259 | 9 | * |
10 | * This file is part of Catacomb. | |
11 | * | |
12 | * Catacomb is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU Library General Public License as | |
14 | * published by the Free Software Foundation; either version 2 of the | |
15 | * License, or (at your option) any later version. | |
45c0fd36 | 16 | * |
893c6259 | 17 | * Catacomb is distributed in the hope that it will be useful, |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | * GNU Library General Public License for more details. | |
45c0fd36 | 21 | * |
893c6259 | 22 | * You should have received a copy of the GNU Library General Public |
23 | * License along with Catacomb; if not, write to the Free | |
24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, | |
25 | * MA 02111-1307, USA. | |
26 | */ | |
27 | ||
893c6259 | 28 | #ifndef CATACOMB_MPRAND_H |
29 | #define CATACOMB_MPRAND_H | |
30 | ||
31 | #ifdef __cplusplus | |
32 | extern "C" { | |
33 | #endif | |
34 | ||
35 | /*----- Header files ------------------------------------------------------*/ | |
36 | ||
37 | #ifndef CATACOMB_GRAND_H | |
38 | # include "grand.h" | |
39 | #endif | |
40 | ||
41 | #ifndef CATACOMB_MP_H | |
42 | # include "mp.h" | |
43 | #endif | |
44 | ||
45 | /*----- Functions provided ------------------------------------------------*/ | |
46 | ||
47 | /* --- @mprand@ --- * | |
48 | * | |
49 | * Arguments: @mp *d@ = destination integer | |
50 | * @unsigned b@ = number of bits | |
51 | * @grand *r@ = pointer to random number source | |
52 | * @mpw or@ = mask to OR with low-order bits | |
53 | * | |
54 | * Returns: A random integer with the requested number of bits | |
55 | * | |
56 | * Use: Constructs an arbitrarily large pseudorandom integer. | |
57 | * Assuming that the generator @r@ is good, the result is | |
58 | * uniformly distributed in the interval %$[2^{b - 1}, 2^b)$%. | |
59 | * The result is then ORred with the given @or@ value. This | |
60 | * will often be 1, to make the result odd. | |
423acb94 MW |
61 | * |
62 | * The length @b@ may be zero; but %$\texttt{or} \ge 2^b$% is | |
63 | * not permitted. | |
893c6259 | 64 | */ |
65 | ||
66 | extern mp *mprand(mp */*d*/, unsigned /*b*/, grand */*r*/, mpw /*or*/); | |
67 | ||
743cef23 | 68 | /* --- @mprand_range@ --- * |
69 | * | |
70 | * Arguments: @mp *d@ = destination integer | |
71 | * @mp *l@ = limit for random number | |
72 | * @grand *r@ = random number source | |
73 | * @mpw or@ = mask for low-order bits | |
74 | * | |
45c0fd36 | 75 | * Returns: A pseudorandom integer, unformly distributed over the |
743cef23 | 76 | * interval %$[0, l)$%. |
77 | * | |
78 | * Use: Generates a uniformly-distributed pseudorandom number in the | |
423acb94 | 79 | * appropriate range. We must have %$l > 0$%. |
743cef23 | 80 | */ |
81 | ||
82 | extern mp *mprand_range(mp */*d*/, mp */*l*/, grand */*r*/, mpw /*or*/); | |
83 | ||
893c6259 | 84 | /*----- That's all, folks -------------------------------------------------*/ |
85 | ||
86 | #ifdef __cplusplus | |
87 | } | |
88 | #endif | |
89 | ||
90 | #endif |