MFC r1.12 (HEAD):
[dragonfly.git] / usr.sbin / pppd / magic.c
blob316ce060945b985f0f2fad3d58d264c96b6d8fff
1 /*
2 * magic.c - PPP Magic Number routines.
4 * Copyright (c) 1989 Carnegie Mellon University.
5 * All rights reserved.
7 * Redistribution and use in source and binary forms are permitted
8 * provided that the above copyright notice and this paragraph are
9 * duplicated in all such forms and that any documentation,
10 * advertising materials, and other materials related to such
11 * distribution and use acknowledge that the software was developed
12 * by Carnegie Mellon University. The name of the
13 * University may not be used to endorse or promote products derived
14 * from this software without specific prior written permission.
15 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
17 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19 * $FreeBSD: src/usr.sbin/pppd/magic.c,v 1.8 1999/08/28 01:19:05 peter Exp $
20 * $DragonFly: src/usr.sbin/pppd/magic.c,v 1.4 2005/11/24 23:42:54 swildner Exp $
23 #include <stdio.h>
24 #include <unistd.h>
25 #include <sys/types.h>
26 #include <sys/time.h>
28 #include "pppd.h"
29 #include "magic.h"
31 extern long mrand48(void);
32 extern void srand48(long);
35 * magic_init - Initialize the magic number generator.
37 * Attempts to compute a random number seed which will not repeat.
38 * The current method uses the current hostid, current process ID
39 * and current time, currently.
41 void
42 magic_init(void)
44 long seed;
45 struct timeval t;
47 gettimeofday(&t, NULL);
48 seed = get_host_seed() ^ t.tv_sec ^ t.tv_usec ^ getpid();
49 srand48(seed);
53 * magic - Returns the next magic number.
55 u_int32_t
56 magic(void)
58 return (u_int32_t) mrand48();
61 #ifdef NO_DRAND48
63 * Substitute procedures for those systems which don't have
64 * drand48 et al.
67 double
68 drand48(void)
70 return (double)random() / (double)0x7fffffffL; /* 2**31-1 */
73 long
74 mrand48(void)
76 return random();
79 void
80 srand48(long seedval)
82 srandom((int)seedval);
85 #endif