xref: /openbsd-src/usr.sbin/rdate/rdate.c (revision 47911bd667ac77dc523b8a13ef40b012dbffa741)
1 /*	$OpenBSD: rdate.c,v 1.19 2002/09/08 12:33:42 jakob Exp $	*/
2 /*	$NetBSD: rdate.c,v 1.4 1996/03/16 12:37:45 pk Exp $	*/
3 
4 /*
5  * Copyright (c) 1994 Christos Zoulas
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Christos Zoulas.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * rdate.c: Set the date from the specified host
36  *
37  *	Uses the rfc868 time protocol at socket 37.
38  *	Time is returned as the number of seconds since
39  *	midnight January 1st 1900.
40  */
41 #ifndef lint
42 #if 0
43 from: static char rcsid[] = "$NetBSD: rdate.c,v 1.3 1996/02/22 06:59:18 thorpej Exp $";
44 #else
45 static const char rcsid[] = "$OpenBSD: rdate.c,v 1.19 2002/09/08 12:33:42 jakob Exp $";
46 #endif
47 #endif				/* lint */
48 
49 #include <sys/param.h>
50 #include <sys/time.h>
51 
52 #include <stdio.h>
53 #include <ctype.h>
54 #include <err.h>
55 #include <string.h>
56 #include <unistd.h>
57 #include <time.h>
58 
59 /* there are systems without libutil; for portability */
60 #ifndef NO_UTIL
61 #include <util.h>
62 #else
63 #define logwtmp(a,b,c)
64 #endif
65 
66 void rfc868time_client (const char *, struct timeval *, struct timeval *, int);
67 void ntp_client (const char *, struct timeval *, struct timeval *, int);
68 
69 extern char    *__progname;
70 
71 void
72 usage()
73 {
74 	(void) fprintf(stderr, "Usage: %s [-ncpsa] host\n", __progname);
75 	(void) fprintf(stderr, "  -n: use SNTP instead of RFC868 time protocol\n");
76 	(void) fprintf(stderr, "  -c: correct leap second count\n");
77 	(void) fprintf(stderr, "  -p: just print, don't set\n");
78 	(void) fprintf(stderr, "  -s: just set, don't print\n");
79 	(void) fprintf(stderr, "  -a: use adjtime instead of instant change\n");
80 	(void) fprintf(stderr, "  -v: verbose output\n");
81 }
82 
83 int
84 main(int argc, char **argv)
85 {
86 	int             pr = 0, silent = 0, ntp = 0, verbose = 0;
87 	int		slidetime = 0, corrleaps = 0;
88 	char           *hname;
89 	extern int      optind;
90 	int             c;
91 
92 	struct timeval new, adjust;
93 
94 	while ((c = getopt(argc, argv, "psancv")) != -1)
95 		switch (c) {
96 		case 'p':
97 			pr++;
98 			break;
99 
100 		case 's':
101 			silent++;
102 			break;
103 
104 		case 'a':
105 			slidetime++;
106 			break;
107 
108 		case 'n':
109 			ntp++;
110 			break;
111 
112 		case 'c':
113 			corrleaps = 1;
114 			break;
115 
116 		case 'v':
117 			verbose++;
118 			break;
119 
120 		default:
121 			usage();
122 			return 1;
123 		}
124 
125 	if (argc - 1 != optind) {
126 		usage();
127 		return 1;
128 	}
129 	hname = argv[optind];
130 
131 	if (ntp)
132 		ntp_client(hname, &new, &adjust, corrleaps);
133 	else
134 		rfc868time_client(hname, &new, &adjust, corrleaps);
135 
136 	if (!pr) {
137 		if (!slidetime) {
138 			logwtmp("|", "date", "");
139 			if (settimeofday(&new, NULL) == -1)
140 				err(1, "Could not set time of day");
141 			logwtmp("{", "date", "");
142 		} else {
143 			if (adjtime(&adjust, NULL) == -1)
144 				err(1, "Could not adjust time of day");
145 		}
146 	}
147 
148 	if (!silent) {
149 		struct tm      *ltm;
150 		char		buf[80];
151 		time_t		tim = new.tv_sec;
152 		double		adjsec;
153 
154 		ltm = localtime(&tim);
155 		(void) strftime(buf, sizeof buf, "%a %b %e %H:%M:%S %Z %Y\n", ltm);
156 		(void) fputs(buf, stdout);
157 
158 		adjsec  = adjust.tv_sec + adjust.tv_usec / 1.0e6;
159 
160 		if (slidetime || verbose) {
161 			if (ntp)
162 				(void) fprintf(stdout,
163 				   "%s: adjust local clock by %.6f seconds\n",
164 				   __progname, adjsec);
165 			else
166 				(void) fprintf(stdout,
167 				   "%s: adjust local clock by %ld seconds\n",
168 				   __progname, adjust.tv_sec);
169 		}
170 	}
171 
172 	return 0;
173 }
174