date.c revision 1.1.1.3 
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
34#ifndef lint
35static char copyright[] =
36"@(#) Copyright (c) 1985, 1987, 1988, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41static char sccsid[] = "@(#)date.c	8.2 (Berkeley) 4/28/95";
42#endif /* not lint */
43
44#include <sys/param.h>
45#include <sys/time.h>
46
47#include <ctype.h>
48#include <err.h>
49#include <fcntl.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53#include <syslog.h>
54#include <unistd.h>
55
56#include "extern.h"
57
58time_t tval;
59int retval, nflag;
60
61static void setthetime __P((char *));
62static void badformat __P((void));
63static void usage __P((void));
64
65int logwtmp __P((char *, char *, char *));
66
67int
68main(argc, argv)
69	int argc;
70	char **argv;
71{
72	extern int optind;
73	extern char *optarg;
74	struct timezone tz;
75	int ch, rflag;
76	char *format, buf[1024];
77
78	tz.tz_dsttime = tz.tz_minuteswest = 0;
79	rflag = 0;
80	while ((ch = getopt(argc, argv, "d:nr:ut:")) != -1)
81		switch((char)ch) {
82		case 'd':		/* daylight savings time */
83			tz.tz_dsttime = atoi(optarg) ? 1 : 0;
84			break;
85		case 'n':		/* don't set network */
86			nflag = 1;
87			break;
88		case 'r':		/* user specified seconds */
89			rflag = 1;
90			tval = atol(optarg);
91			break;
92		case 'u':		/* do everything in GMT */
93			(void)setenv("TZ", "GMT0", 1);
94			break;
95		case 't':		/* minutes west of GMT */
96					/* error check; don't allow "PST" */
97			if (isdigit(*optarg)) {
98				tz.tz_minuteswest = atoi(optarg);
99				break;
100			}
101			/* FALLTHROUGH */
102		default:
103			usage();
104		}
105	argc -= optind;
106	argv += optind;
107
108	/*
109	 * If -d or -t, set the timezone or daylight savings time; this
110	 * doesn't belong here, there kernel should not know about either.
111	 */
112	if ((tz.tz_minuteswest || tz.tz_dsttime) &&
113	    settimeofday(NULL, &tz))
114		err(1, "settimeofday");
115
116	if (!rflag && time(&tval) == -1)
117		err(1, "time");
118
119	format = "%a %b %e %H:%M:%S %Z %Y";
120
121	/* allow the operands in any order */
122	if (*argv && **argv == '+') {
123		format = *argv + 1;
124		++argv;
125	}
126
127	if (*argv) {
128		setthetime(*argv);
129		++argv;
130	}
131
132	if (*argv && **argv == '+')
133		format = *argv + 1;
134
135	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
136	(void)printf("%s\n", buf);
137	exit(retval);
138}
139
140#define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
141void
142setthetime(p)
143	register char *p;
144{
145	register struct tm *lt;
146	struct timeval tv;
147	char *dot, *t;
148
149	for (t = p, dot = NULL; *t; ++t) {
150		if (isdigit(*t))
151			continue;
152		if (*t == '.' && dot == NULL) {
153			dot = t;
154			continue;
155		}
156		badformat();
157	}
158
159	lt = localtime(&tval);
160
161	if (dot != NULL) {			/* .ss */
162		*dot++ = '\0';
163		if (strlen(dot) != 2)
164			badformat();
165		lt->tm_sec = ATOI2(dot);
166		if (lt->tm_sec > 61)
167			badformat();
168	} else
169		lt->tm_sec = 0;
170
171	switch (strlen(p)) {
172	case 10:				/* yy */
173		lt->tm_year = ATOI2(p);
174		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
175			lt->tm_year += 100;
176		/* FALLTHROUGH */
177	case 8:					/* mm */
178		lt->tm_mon = ATOI2(p);
179		if (lt->tm_mon > 12)
180			badformat();
181		--lt->tm_mon;			/* time struct is 0 - 11 */
182		/* FALLTHROUGH */
183	case 6:					/* dd */
184		lt->tm_mday = ATOI2(p);
185		if (lt->tm_mday > 31)
186			badformat();
187		/* FALLTHROUGH */
188	case 4:					/* hh */
189		lt->tm_hour = ATOI2(p);
190		if (lt->tm_hour > 23)
191			badformat();
192		/* FALLTHROUGH */
193	case 2:					/* mm */
194		lt->tm_min = ATOI2(p);
195		if (lt->tm_min > 59)
196			badformat();
197		break;
198	default:
199		badformat();
200	}
201
202	/* convert broken-down time to GMT clock time */
203	if ((tval = mktime(lt)) == -1)
204		badformat();
205
206	/* set the time */
207	if (nflag || netsettime(tval)) {
208		logwtmp("|", "date", "");
209		tv.tv_sec = tval;
210		tv.tv_usec = 0;
211		if (settimeofday(&tv, NULL)) {
212			perror("date: settimeofday");
213			exit(1);
214		}
215		logwtmp("{", "date", "");
216	}
217
218	if ((p = getlogin()) == NULL)
219		p = "???";
220	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
221}
222
223static void
224badformat()
225{
226	warnx("illegal time format");
227	usage();
228}
229
230static void
231usage()
232{
233	(void)fprintf(stderr,
234	    "usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]\n");
235	(void)fprintf(stderr, "            [yy[mm[dd[hh]]]]mm[.ss]]\n");
236	exit(1);
237}
238