date.c revision 1.1 
1/*
2 * Copyright (c) 1985, 1987, 1988 The Regents of the University of California.
3 * 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
35char copyright[] =
36"@(#) Copyright (c) 1985, 1987, 1988 The Regents of the University of California.\n\
37 All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41static char sccsid[] = "@(#)date.c	5.5 (Berkeley) 3/18/91";
42#endif /* not lint */
43
44#include <sys/param.h>
45#include <sys/time.h>
46#include <sys/file.h>
47#include <syslog.h>
48#include <unistd.h>
49#include <stdio.h>
50#include <stdlib.h>
51#include <string.h>
52#include <ctype.h>
53
54time_t tval;
55int retval, nflag;
56
57main(argc, argv)
58	int argc;
59	char **argv;
60{
61	extern int optind;
62	extern char *optarg;
63	struct timezone tz;
64	int ch, rflag;
65	char *format, buf[1024];
66
67	tz.tz_dsttime = tz.tz_minuteswest = 0;
68	rflag = 0;
69	while ((ch = getopt(argc, argv, "d:nr:ut:")) != EOF)
70		switch((char)ch) {
71		case 'd':		/* daylight savings time */
72			tz.tz_dsttime = atoi(optarg) ? 1 : 0;
73			break;
74		case 'n':		/* don't set network */
75			nflag = 1;
76			break;
77		case 'r':		/* user specified seconds */
78			rflag = 1;
79			tval = atol(optarg);
80			break;
81		case 'u':		/* do everything in GMT */
82			(void)setenv("TZ", "GMT0", 1);
83			break;
84		case 't':		/* minutes west of GMT */
85					/* error check; don't allow "PST" */
86			if (isdigit(*optarg)) {
87				tz.tz_minuteswest = atoi(optarg);
88				break;
89			}
90			/* FALLTHROUGH */
91		default:
92			usage();
93		}
94	argc -= optind;
95	argv += optind;
96
97	/*
98	 * If -d or -t, set the timezone or daylight savings time; this
99	 * doesn't belong here, there kernel should not know about either.
100	 */
101	if ((tz.tz_minuteswest || tz.tz_dsttime) &&
102	    settimeofday((struct timeval *)NULL, &tz)) {
103		perror("date: settimeofday");
104		exit(1);
105	}
106
107	if (!rflag && time(&tval) == -1) {
108		perror("date: time");
109		exit(1);
110	}
111
112	format = "%a %b %e %H:%M:%S %Z %Y\n";
113
114	/* allow the operands in any order */
115	if (*argv && **argv == '+') {
116		format = *argv + 1;
117		++argv;
118	}
119
120	if (*argv) {
121		setthetime(*argv);
122		++argv;
123	}
124
125	if (*argv && **argv == '+')
126		format = *argv + 1;
127
128	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
129	(void)printf("%s", buf);
130	exit(retval);
131}
132
133#define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
134setthetime(p)
135	register char *p;
136{
137	register struct tm *lt;
138	struct timeval tv;
139	int dot;
140	char *t;
141
142	for (t = p, dot = 0; *t; ++t)
143		if (!isdigit(*t) && (*t != '.' || dot++))
144			badformat();
145
146	lt = localtime(&tval);
147
148	if (t = index(p, '.')) {		/* .ss */
149		*t++ = '\0';
150		if (lt->tm_sec > 61)
151			badformat();
152	} else
153		lt->tm_sec = 0;
154
155	for (t = p; *t; ++t)
156		if (!isdigit(*t))
157			badformat();
158
159	switch (strlen(p)) {
160	case 10:				/* yy */
161		lt->tm_year = ATOI2(p);
162		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
163			lt->tm_year += 100;
164		/* FALLTHROUGH */
165	case 8:					/* mm */
166		lt->tm_mon = ATOI2(p);
167		if (lt->tm_mon > 12)
168			badformat();
169		--lt->tm_mon;			/* time struct is 0 - 11 */
170		/* FALLTHROUGH */
171	case 6:					/* dd */
172		lt->tm_mday = ATOI2(p);
173		if (lt->tm_mday > 31)
174			badformat();
175		/* FALLTHROUGH */
176	case 4:					/* hh */
177		lt->tm_hour = ATOI2(p);
178		if (lt->tm_hour > 23)
179			badformat();
180		/* FALLTHROUGH */
181	case 2:					/* mm */
182		lt->tm_min = ATOI2(p);
183		if (lt->tm_min > 59)
184			badformat();
185		break;
186	default:
187		badformat();
188	}
189
190	/* convert broken-down time to GMT clock time */
191	if ((tval = mktime(lt)) == -1)
192		badformat();
193
194	if (!(p = getlogin()))			/* single-user or no tty */
195		p = "root";
196	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
197
198	/* set the time */
199	if (nflag || netsettime(tval)) {
200		logwtmp("|", "date", "");
201		tv.tv_sec = tval;
202		tv.tv_usec = 0;
203		if (settimeofday(&tv, (struct timezone *)NULL)) {
204			perror("date: settimeofday");
205			exit(1);
206		}
207		logwtmp("{", "date", "");
208	}
209}
210
211badformat()
212{
213	(void)fprintf(stderr, "date: illegal time format.\n");
214	usage();
215}
216
217usage()
218{
219	(void)fprintf(stderr,
220	    "usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]\n");
221	(void)fprintf(stderr, "            [yy[mm[dd[hh]]]]mm[.ss]]\n");
222	exit(1);
223}
224