date.c revision 9944 
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 1.4 1995/04/03 20:08:33 joerg Exp $
34 */
35
36#ifndef lint
37static char 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 sccsid[] = "@(#)date.c	8.1 (Berkeley) 5/31/93";
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
58#include "extern.h"
59
60time_t tval;
61int retval, nflag;
62
63static void setthetime __P((char *));
64static void badformat __P((void));
65static void usage __P((void));
66
67int logwtmp __P((char *, char *, char *));
68
69int
70main(argc, argv)
71	int argc;
72	char **argv;
73{
74	extern int optind;
75	extern char *optarg;
76	struct timezone tz;
77	int ch, rflag;
78	char *format, buf[1024];
79	char *endptr;
80	int set_timezone;
81
82	tz.tz_dsttime = tz.tz_minuteswest = 0;
83	rflag = 0;
84	set_timezone = 0;
85	while ((ch = getopt(argc, argv, "d:nr:ut:")) != EOF)
86		switch((char)ch) {
87		case 'd':		/* daylight savings time */
88			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
89			if (endptr == optarg || *endptr != '\0')
90				usage();
91			set_timezone = 1;
92			break;
93		case 'n':		/* don't set network */
94			nflag = 1;
95			break;
96		case 'r':		/* user specified seconds */
97			rflag = 1;
98			tval = atol(optarg);
99			break;
100		case 'u':		/* do everything in GMT */
101			(void)setenv("TZ", "GMT0", 1);
102			break;
103		case 't':		/* minutes west of GMT */
104					/* error check; don't allow "PST" */
105			tz.tz_minuteswest = strtol(optarg, &endptr, 10);
106			if (endptr == optarg || *endptr != '\0')
107				usage();
108			set_timezone = 1;
109			break;
110		default:
111			usage();
112		}
113	argc -= optind;
114	argv += optind;
115
116	/*
117	 * If -d or -t, set the timezone or daylight savings time; this
118	 * doesn't belong here, there kernel should not know about either.
119	 */
120	if (set_timezone && settimeofday((struct timeval *)NULL, &tz))
121		err(1, "settimeofday (timezone)");
122
123	if (!rflag && time(&tval) == -1)
124		err(1, "time");
125
126	format = "%+";
127
128	/* allow the operands in any order */
129	if (*argv && **argv == '+') {
130		format = *argv + 1;
131		++argv;
132	}
133
134	if (*argv) {
135		setthetime(*argv);
136		++argv;
137	}
138
139	if (*argv && **argv == '+')
140		format = *argv + 1;
141
142	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
143	(void)printf("%s\n", buf);
144	exit(retval);
145}
146
147#define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
148void
149setthetime(p)
150	register char *p;
151{
152	register struct tm *lt;
153	struct timeval tv;
154	char *dot, *t;
155
156	for (t = p, dot = NULL; *t; ++t) {
157		if (isdigit(*t))
158			continue;
159		if (*t == '.' && dot == NULL) {
160			dot = t;
161			continue;
162		}
163		badformat();
164	}
165
166	lt = localtime(&tval);
167
168	if (dot != NULL) {			/* .ss */
169		*dot++ = '\0';
170		if (strlen(dot) != 2)
171			badformat();
172		lt->tm_sec = ATOI2(dot);
173		if (lt->tm_sec > 61)
174			badformat();
175	} else
176		lt->tm_sec = 0;
177
178	switch (strlen(p)) {
179	case 10:				/* yy */
180		lt->tm_year = ATOI2(p);
181		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
182			lt->tm_year += 100;
183		/* FALLTHROUGH */
184	case 8:					/* mm */
185		lt->tm_mon = ATOI2(p);
186		if (lt->tm_mon > 12)
187			badformat();
188		--lt->tm_mon;			/* time struct is 0 - 11 */
189		/* FALLTHROUGH */
190	case 6:					/* dd */
191		lt->tm_mday = ATOI2(p);
192		if (lt->tm_mday > 31)
193			badformat();
194		/* FALLTHROUGH */
195	case 4:					/* hh */
196		lt->tm_hour = ATOI2(p);
197		if (lt->tm_hour > 23)
198			badformat();
199		/* FALLTHROUGH */
200	case 2:					/* mm */
201		lt->tm_min = ATOI2(p);
202		if (lt->tm_min > 59)
203			badformat();
204		break;
205	default:
206		badformat();
207	}
208
209	/* convert broken-down time to GMT clock time */
210	if ((tval = mktime(lt)) == -1)
211		badformat();
212
213	/* set the time */
214	if (nflag || netsettime(tval)) {
215		logwtmp("|", "date", "");
216		tv.tv_sec = tval;
217		tv.tv_usec = 0;
218		if (settimeofday(&tv, (struct timezone *)NULL))
219			err(1, "settimeofday (timeval)");
220		logwtmp("{", "date", "");
221	}
222
223	if ((p = getlogin()) == NULL)
224		p = "???";
225	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
226}
227
228static void
229badformat()
230{
231	warnx("illegal time format");
232	usage();
233}
234
235static void
236usage()
237{
238	(void)fprintf(stderr,
239	    "usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]\n");
240	(void)fprintf(stderr, "            [yy[mm[dd[hh]]]]mm[.ss]]\n");
241	exit(1);
242}
243