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
|
/* xscreensaver, Copyright (c) 1997, 1998, 2003 by Jamie Zawinski <jwz@jwz.org>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. No representations are made about the suitability of this
* software for any purpose. It is provided "as is" without express or
* implied warranty.
*/
#ifndef __YARANDOM_H__
#define __YARANDOM_H__
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_INTTYPES_H
# include <inttypes.h>
#endif
#undef random
#undef rand
#undef drand48
#undef srandom
#undef srand
#undef srand48
#undef frand
#undef RAND_MAX
#ifdef VMS
# include "vms-gtod.h"
#endif
extern unsigned int ya_random (void);
extern void ya_rand_init (unsigned int);
#define random() ya_random()
#define RAND_MAX 0xFFFFFFFF
/*#define srandom(i) ya_rand_init(0)*/
/* Define these away to keep people from using the wrong APIs in xscreensaver.
*/
#define rand __ERROR_use_random_not_rand_in_xscreensaver__
#define drand48 __ERROR_use_frand_not_drand48_in_xscreensaver__
#define srandom __ERROR_do_not_call_srandom_in_xscreensaver__
#define srand __ERROR_do_not_call_srand_in_xscreensaver__
#define srand48 __ERROR_do_not_call_srand48_in_xscreensaver__
#define ya_rand_init __ERROR_do_not_call_ya_rand_init_in_xscreensaver__
#if defined (__GNUC__) && (__GNUC__ >= 2)
/* Implement frand using GCC's statement-expression extension. */
# define frand(f) \
__extension__ \
({ double tmp = ((((double) random()) * ((double) (f))) / \
((double) ((unsigned int)~0))); \
tmp < 0 ? (-tmp) : tmp; })
#else /* not GCC2 - implement frand using a global variable.*/
static double _frand_tmp_;
# define frand(f) \
(_frand_tmp_ = ((((double) random()) * ((double) (f))) / \
((double) ((unsigned int)~0))), \
_frand_tmp_ < 0 ? (-_frand_tmp_) : _frand_tmp_)
#endif /* not GCC2 */
/* Compatibility with the xlockmore RNG API
(note that the xlockmore hacks never expect negative numbers.)
*/
#define LRAND() ((long) (random() & 0x7fffffff))
/* The first NRAND(n) is much faster, when uint64_t is available to allow it.
* Especially on ARM and other processors without built-in division.
*
* n must be greater than zero.
*
* The division by RAND_MAX+1 should optimize down to a bit shift.
*
* Although the result here is never negative, this needs to return signed
* integers: A binary operator in C requires operands have the same type, and
* if one side is signed and the other is unsigned, but they're both the same
* size, then the signed operand is cast to unsigned, and the result is
* similarly unsigned. This can potentially cause problems when idioms like
* "NRAND(n) * RANDSIGN()" (where RANDSIGN() returns either -1 or 1) is used
* to get random numbers from the range (-n,n).
*/
#ifdef HAVE_INTTYPES_H
# define NRAND(n) ((int32_t) ((uint64_t) random() * (uint32_t) (n) / \
((uint64_t) RAND_MAX + 1)))
#else
# define NRAND(n) ((int) (LRAND() % (n)))
#endif
#define MAXRAND (2147483648.0) /* unsigned 1<<31 as a float */
#define SRAND(n) /* already seeded by screenhack.c */
#endif /* __YARANDOM_H__ */
|
