xref: /freebsd/bin/date/date.c (revision 17ee9d00bc1ae1e598c38f25826f861e4bc6c3ce)
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 1.2 1994/09/24 02:54:36 davidg Exp $
34  */
35 
36 #ifndef lint
37 static 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
43 static 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 
60 time_t tval;
61 int retval, nflag;
62 
63 static void setthetime __P((char *));
64 static void badformat __P((void));
65 static void usage __P((void));
66 
67 int logwtmp __P((char *, char *, char *));
68 
69 int
70 main(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 = "%a %b %e %H:%M:%S %Z %Y\n";
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", buf);
144 	exit(retval);
145 }
146 
147 #define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
148 void
149 setthetime(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 
228 static void
229 badformat()
230 {
231 	warnx("illegal time format");
232 	usage();
233 }
234 
235 static void
236 usage()
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