date.c revision 27874
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 1.13 1997/06/06 06:34:37 charnier 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#include "vary.h"
61
62time_t tval;
63int retval, nflag;
64
65static void setthetime __P((char *));
66static void badformat __P((void));
67static void usage __P((void));
68
69int logwtmp __P((char *, char *, char *));
70
71int
72main(argc, argv)
73	int argc;
74	char **argv;
75{
76	extern int optind;
77	extern char *optarg;
78	struct timezone tz;
79	int ch, rflag;
80	char *format, buf[1024];
81	char *endptr;
82	int set_timezone;
83	struct vary *v;
84	const struct vary *badv;
85	struct tm lt;
86
87	v = NULL;
88	(void) setlocale(LC_TIME, "");
89	tz.tz_dsttime = tz.tz_minuteswest = 0;
90	rflag = 0;
91	set_timezone = 0;
92	while ((ch = getopt(argc, argv, "D:W:M:Y:d:nr:ut:")) != -1)
93		switch((char)ch) {
94		case 'd':		/* daylight savings time */
95			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
96			if (endptr == optarg || *endptr != '\0')
97				usage();
98			set_timezone = 1;
99			break;
100		case 'n':		/* don't set network */
101			nflag = 1;
102			break;
103		case 'r':		/* user specified seconds */
104			rflag = 1;
105			tval = atol(optarg);
106			break;
107		case 'u':		/* do everything in GMT */
108			(void)setenv("TZ", "GMT0", 1);
109			break;
110		case 't':		/* minutes west of GMT */
111					/* error check; don't allow "PST" */
112			tz.tz_minuteswest = strtol(optarg, &endptr, 10);
113			if (endptr == optarg || *endptr != '\0')
114				usage();
115			set_timezone = 1;
116			break;
117		case 'D':
118		case 'W':
119		case 'M':
120		case 'Y':
121			v = vary_append(v, ch, optarg);
122			break;
123		default:
124			usage();
125		}
126	argc -= optind;
127	argv += optind;
128
129	/*
130	 * If -d or -t, set the timezone or daylight savings time; this
131	 * doesn't belong here; the kernel should not know about either.
132	 */
133	if (set_timezone && settimeofday((struct timeval *)NULL, &tz))
134		err(1, "settimeofday (timezone)");
135
136	if (!rflag && time(&tval) == -1)
137		err(1, "time");
138
139	format = "%+";
140
141	/* allow the operands in any order */
142	if (*argv && **argv == '+') {
143		format = *argv + 1;
144		++argv;
145	}
146
147	if (*argv) {
148		setthetime(*argv);
149		++argv;
150	}
151
152	if (*argv && **argv == '+')
153		format = *argv + 1;
154
155	lt = *localtime(&tval);
156	badv = vary_apply(v, &lt);
157	if (badv) {
158		fprintf(stderr, "-%c %s: Cannot apply date adjustment\n",
159			badv->flag, badv->arg);
160		vary_destroy(v);
161		usage();
162	}
163	vary_destroy(v);
164	(void)strftime(buf, sizeof(buf), format, &lt);
165	(void)printf("%s\n", buf);
166	exit(retval);
167}
168
169#define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
170void
171setthetime(p)
172	register char *p;
173{
174	register struct tm *lt;
175	struct timeval tv;
176	char *dot, *t;
177
178	for (t = p, dot = NULL; *t; ++t) {
179		if (isdigit(*t))
180			continue;
181		if (*t == '.' && dot == NULL) {
182			dot = t;
183			continue;
184		}
185		badformat();
186	}
187
188	lt = localtime(&tval);
189
190	if (dot != NULL) {			/* .ss */
191		*dot++ = '\0';
192		if (strlen(dot) != 2)
193			badformat();
194		lt->tm_sec = ATOI2(dot);
195		if (lt->tm_sec > 61)
196			badformat();
197	} else
198		lt->tm_sec = 0;
199
200	switch (strlen(p)) {
201	case 10:				/* yy */
202		lt->tm_year = ATOI2(p);
203		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
204			lt->tm_year += 100;
205		/* FALLTHROUGH */
206	case 8:					/* mm */
207		lt->tm_mon = ATOI2(p);
208		if (lt->tm_mon > 12)
209			badformat();
210		--lt->tm_mon;			/* time struct is 0 - 11 */
211		/* FALLTHROUGH */
212	case 6:					/* dd */
213		lt->tm_mday = ATOI2(p);
214		if (lt->tm_mday > 31)
215			badformat();
216		/* FALLTHROUGH */
217	case 4:					/* hh */
218		lt->tm_hour = ATOI2(p);
219		if (lt->tm_hour > 23)
220			badformat();
221		/* FALLTHROUGH */
222	case 2:					/* mm */
223		lt->tm_min = ATOI2(p);
224		if (lt->tm_min > 59)
225			badformat();
226		break;
227	default:
228		badformat();
229	}
230
231	/* convert broken-down time to GMT clock time */
232	if ((tval = mktime(lt)) == -1)
233		errx(1, "nonexistent time");
234
235	/* set the time */
236	if (nflag || netsettime(tval)) {
237		logwtmp("|", "date", "");
238		tv.tv_sec = tval;
239		tv.tv_usec = 0;
240		if (settimeofday(&tv, (struct timezone *)NULL))
241			err(1, "settimeofday (timeval)");
242		logwtmp("{", "date", "");
243	}
244
245	if ((p = getlogin()) == NULL)
246		p = "???";
247	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
248}
249
250static void
251badformat()
252{
253	warnx("illegal time format");
254	usage();
255}
256
257static void
258usage()
259{
260	(void)fprintf(stderr, "%s\n%s\n",
261		"usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]",
262		"            [-DWMY [+|-]val] [[[[yy]mm]dd]HH]MM[.ss]]");
263	exit(1);
264}
265