date.c revision 24348 
1/*
2 * Copyright (c) 1985, 1987, 1988, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	$Id: date.c,v 1.10 1997/02/22 14:02:33 peter Exp $
34 */
35
36#ifndef lint
37static char const copyright[] =
38"@(#) Copyright (c) 1985, 1987, 1988, 1993\n\
39	The Regents of the University of California.  All rights reserved.\n";
40#endif /* not lint */
41
42#ifndef lint
43static char const sccsid[] = "@(#)date.c	8.2 (Berkeley) 4/28/95";
44#endif /* not lint */
45
46#include <sys/param.h>
47#include <sys/time.h>
48
49#include <ctype.h>
50#include <err.h>
51#include <fcntl.h>
52#include <stdio.h>
53#include <stdlib.h>
54#include <string.h>
55#include <syslog.h>
56#include <unistd.h>
57#include <locale.h>
58
59#include "extern.h"
60
61time_t tval;
62int retval, nflag;
63
64static void setthetime __P((char *));
65static void badformat __P((void));
66static void usage __P((void));
67
68int logwtmp __P((char *, char *, char *));
69
70int
71main(argc, argv)
72	int argc;
73	char **argv;
74{
75	extern int optind;
76	extern char *optarg;
77	struct timezone tz;
78	int ch, rflag;
79	char *format, buf[1024];
80	char *endptr;
81	int set_timezone;
82
83	(void) setlocale(LC_TIME, "");
84	tz.tz_dsttime = tz.tz_minuteswest = 0;
85	rflag = 0;
86	set_timezone = 0;
87	while ((ch = getopt(argc, argv, "d:nr:ut:")) != -1)
88		switch((char)ch) {
89		case 'd':		/* daylight savings time */
90			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
91			if (endptr == optarg || *endptr != '\0')
92				usage();
93			set_timezone = 1;
94			break;
95		case 'n':		/* don't set network */
96			nflag = 1;
97			break;
98		case 'r':		/* user specified seconds */
99			rflag = 1;
100			tval = atol(optarg);
101			break;
102		case 'u':		/* do everything in GMT */
103			(void)setenv("TZ", "GMT0", 1);
104			break;
105		case 't':		/* minutes west of GMT */
106					/* error check; don't allow "PST" */
107			tz.tz_minuteswest = strtol(optarg, &endptr, 10);
108			if (endptr == optarg || *endptr != '\0')
109				usage();
110			set_timezone = 1;
111			break;
112		default:
113			usage();
114		}
115	argc -= optind;
116	argv += optind;
117
118	/*
119	 * If -d or -t, set the timezone or daylight savings time; this
120	 * doesn't belong here, there kernel should not know about either.
121	 */
122	if (set_timezone && settimeofday((struct timeval *)NULL, &tz))
123		err(1, "settimeofday (timezone)");
124
125	if (!rflag && time(&tval) == -1)
126		err(1, "time");
127
128	format = "%+";
129
130	/* allow the operands in any order */
131	if (*argv && **argv == '+') {
132		format = *argv + 1;
133		++argv;
134	}
135
136	if (*argv) {
137		setthetime(*argv);
138		++argv;
139	}
140
141	if (*argv && **argv == '+')
142		format = *argv + 1;
143
144	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
145	(void)printf("%s\n", buf);
146	exit(retval);
147}
148
149#define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
150void
151setthetime(p)
152	register char *p;
153{
154	register struct tm *lt;
155	struct timeval tv;
156	char *dot, *t;
157
158	for (t = p, dot = NULL; *t; ++t) {
159		if (isdigit(*t))
160			continue;
161		if (*t == '.' && dot == NULL) {
162			dot = t;
163			continue;
164		}
165		badformat();
166	}
167
168	lt = localtime(&tval);
169
170	if (dot != NULL) {			/* .ss */
171		*dot++ = '\0';
172		if (strlen(dot) != 2)
173			badformat();
174		lt->tm_sec = ATOI2(dot);
175		if (lt->tm_sec > 61)
176			badformat();
177	} else
178		lt->tm_sec = 0;
179
180	switch (strlen(p)) {
181	case 10:				/* yy */
182		lt->tm_year = ATOI2(p);
183		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
184			lt->tm_year += 100;
185		/* FALLTHROUGH */
186	case 8:					/* mm */
187		lt->tm_mon = ATOI2(p);
188		if (lt->tm_mon > 12)
189			badformat();
190		--lt->tm_mon;			/* time struct is 0 - 11 */
191		/* FALLTHROUGH */
192	case 6:					/* dd */
193		lt->tm_mday = ATOI2(p);
194		if (lt->tm_mday > 31)
195			badformat();
196		/* FALLTHROUGH */
197	case 4:					/* hh */
198		lt->tm_hour = ATOI2(p);
199		if (lt->tm_hour > 23)
200			badformat();
201		/* FALLTHROUGH */
202	case 2:					/* mm */
203		lt->tm_min = ATOI2(p);
204		if (lt->tm_min > 59)
205			badformat();
206		break;
207	default:
208		badformat();
209	}
210
211	/* convert broken-down time to GMT clock time */
212	if ((tval = mktime(lt)) == -1)
213		errx(1, "nonexistent time");
214
215	/* set the time */
216	if (nflag || netsettime(tval)) {
217		logwtmp("|", "date", "");
218		tv.tv_sec = tval;
219		tv.tv_usec = 0;
220		if (settimeofday(&tv, (struct timezone *)NULL))
221			err(1, "settimeofday (timeval)");
222		logwtmp("{", "date", "");
223	}
224
225	if ((p = getlogin()) == NULL)
226		p = "???";
227	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
228}
229
230static void
231badformat()
232{
233	warnx("illegal time format");
234	usage();
235}
236
237static void
238usage()
239{
240	(void)fprintf(stderr,
241	    "usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]\n");
242	(void)fprintf(stderr, "            [yy[mm[dd[hh]]]]mm[.ss]]\n");
243	exit(1);
244}
245