1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/* Random kit 1.6 */
/*
* Anyone who attempts to generate random numbers by deterministic means is,
* of course, living in a state of sin.
* -- John von Neumann
*/
/*
* Copyright (c) 2003-2006, Jean-Sebastien Roy (js@jeannot.org)
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/* @(#) $Jeannot: rk_mt.h,v 1.6 2006/02/20 19:13:37 js Exp $ */
/*
* Typical use:
*
* {
* rk_state state;
* unsigned long seed = 1, random_value;
*
* rk_seed(seed, &state); // Initialize the RNG
* ...
* random_value = rk_random(&state); // a random value in [0..RK_MAX]
* }
*
* Instead of rk_seed, you can use rk_randomseed which will get a random seed
* from /dev/urandom (or the clock, if /dev/urandom is unavailable):
*
* {
* rk_state state;
* unsigned long random_value;
*
* rk_randomseed(&state); // Initialize the RNG with a random seed
* ...
* random_value = rk_random(&state); // a random value in [0..RK_MAX]
* }
*/
/*
* Useful macro:
* RK_DEV_RANDOM: the device used for random seeding.
* defaults to "/dev/urandom"
*/
#include <stddef.h>
#ifndef _RK_MT_
#define _RK_MT_
#define RK_STATE_LEN 624
typedef struct rk_state_
{
unsigned long key[RK_STATE_LEN];
int pos;
int has_gauss; /* !=0: gauss contains a gaussian deviate */
double gauss;
}
rk_state;
typedef enum {
RK_NOERR = 0, /* no error */
RK_ENODEV = 1, /* no RK_DEV_RANDOM device */
RK_ERR_MAX = 2
} rk_error;
/* error strings */
extern char *rk_strerror[RK_ERR_MAX];
/* Maximum generated random value */
#define RK_MAX 0xFFFFFFFFUL
#ifdef __cplusplus
extern "C" {
#endif
/*
* Initialize the RNG state using the given seed.
*/
extern void rk_seed(unsigned long seed, rk_state *state);
/*
* Initialize the RNG state using a random seed.
* Uses /dev/urandom or, when unavailable, the clock (see rk_mt.c).
* Returns RK_NOERR when no errors occurs.
* Returns RK_ENODEV when the use of RK_DEV_RANDOM failed (for example because
* there is no such device). In this case, the RNG was initialized using the
* clock.
*/
extern rk_error rk_randomseed(rk_state *state);
/*
* Returns a random unsigned long between 0 and RK_MAX inclusive
*/
extern unsigned long rk_random(rk_state *state);
/*
* Returns a random long between 0 and LONG_MAX inclusive
*/
extern long rk_long(rk_state *state);
/*
* Returns a random unsigned long between 0 and ULONG_MAX inclusive
*/
extern unsigned long rk_ulong(rk_state *state);
/*
* Returns a random unsigned long between 0 and max inclusive.
*/
extern unsigned long rk_interval(unsigned long max, rk_state *state);
/*
* Returns a random double between 0.0 and 1.0, 1.0 excluded.
*/
extern double rk_double(rk_state *state);
/*
* Copy a random generator state.
*/
extern void rk_copy(rk_state *copy, rk_state *orig);
/*
* fill the buffer with size random bytes.
* If state == NULL, the random generator is inilialized using rk_randomseed.
* Calling multiple times rk_randomseed should be avoided therefore calling
* multiple times rk_fill with state == NULL should be avoided.
*/
extern void rk_fill(void *buffer, size_t size, rk_state *state);
/*
* fill the buffer with randombytes from the random device
* Returns RK_ENODEV if the device is unavailable, or RK_NOERR if it is
* On Unix, if strong is defined, RK_DEV_RANDOM is used. If not, RK_DEV_URANDOM
* is used instead. This parameter has no effect on Windows.
* Warning: on most unixes RK_DEV_RANDOM will wait for enough entropy to answer
* which can take a very long time on quiet systems.
*/
extern rk_error rk_devfill(void *buffer, size_t size, int strong);
/*
* fill the buffer using rk_devfill if the random device is available and using
* rk_fill if is is not
* parameters have the same meaning as rk_fill and rk_devfill
* Returns RK_ENODEV if the device is unavailable, or RK_NOERR if it is
*/
extern rk_error rk_altfill(void *buffer, size_t size, int strong,
rk_state *state);
/*
* return a random gaussian deviate with variance unity and zero mean.
*/
extern double rk_gauss(rk_state *state);
/* Utility functions */
/*
* fill the key vector using Knuth RNG as used in MT reference implementation
* using the provided seed. The key vector length is len.
*/
extern void rk_knuth_fill(unsigned long seed, unsigned long *key,
unsigned long len);
/*
* return a random unsigned long based upon the system state (clock, pid)
* used as seed when there is no random device.
*/
extern unsigned long rk_seedfromsystem(void);
#ifdef __cplusplus
}
#endif
#endif /* _RK_MT_ */
|
