xref: /netbsd-src/bin/date/date.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
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
35 static 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
41 /*static char sccsid[] = "from: @(#)date.c	8.1 (Berkeley) 5/31/93";*/
42 static char *rcsid = "$Id: date.c,v 1.8 1994/09/22 09:24:49 mycroft Exp $";
43 #endif /* not lint */
44 
45 #include <sys/param.h>
46 #include <sys/time.h>
47 
48 #include <ctype.h>
49 #include <err.h>
50 #include <fcntl.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <locale.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 
80 	setlocale(LC_ALL, "");
81 
82 	tz.tz_dsttime = tz.tz_minuteswest = 0;
83 	rflag = 0;
84 	while ((ch = getopt(argc, argv, "d:nr:ut:")) != -1)
85 		switch((char)ch) {
86 		case 'd':		/* daylight savings time */
87 			tz.tz_dsttime = atoi(optarg) ? 1 : 0;
88 			break;
89 		case 'n':		/* don't set network */
90 			nflag = 1;
91 			break;
92 		case 'r':		/* user specified seconds */
93 			rflag = 1;
94 			tval = atol(optarg);
95 			break;
96 		case 'u':		/* do everything in GMT */
97 			(void)setenv("TZ", "GMT0", 1);
98 			break;
99 		case 't':		/* minutes west of GMT */
100 					/* error check; don't allow "PST" */
101 			if (isdigit(*optarg)) {
102 				tz.tz_minuteswest = atoi(optarg);
103 				break;
104 			}
105 			/* FALLTHROUGH */
106 		default:
107 			usage();
108 		}
109 	argc -= optind;
110 	argv += optind;
111 
112 	/*
113 	 * If -d or -t, set the timezone or daylight savings time; this
114 	 * doesn't belong here, there kernel should not know about either.
115 	 */
116 	if ((tz.tz_minuteswest || tz.tz_dsttime) &&
117 	    settimeofday(NULL, &tz))
118 		err(1, "settimeofday");
119 
120 	if (!rflag && time(&tval) == -1)
121 		err(1, "time");
122 
123 	format = "%a %b %e %H:%M:%S %Z %Y";
124 
125 	/* allow the operands in any order */
126 	if (*argv && **argv == '+') {
127 		format = *argv + 1;
128 		++argv;
129 	}
130 
131 	if (*argv) {
132 		setthetime(*argv);
133 		++argv;
134 	}
135 
136 	if (*argv && **argv == '+')
137 		format = *argv + 1;
138 
139 	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
140 	(void)printf("%s\n", buf);
141 	exit(retval);
142 }
143 
144 #define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
145 void
146 setthetime(p)
147 	register char *p;
148 {
149 	register struct tm *lt;
150 	struct timeval tv;
151 	char *dot, *t;
152 
153 	for (t = p, dot = NULL; *t; ++t) {
154 		if (isdigit(*t))
155 			continue;
156 		if (*t == '.' && dot == NULL) {
157 			dot = t;
158 			continue;
159 		}
160 		badformat();
161 	}
162 
163 	lt = localtime(&tval);
164 
165 	if (dot != NULL) {			/* .ss */
166 		*dot++ = '\0';
167 		if (strlen(dot) != 2)
168 			badformat();
169 		lt->tm_sec = ATOI2(dot);
170 		if (lt->tm_sec > 61)
171 			badformat();
172 	} else
173 		lt->tm_sec = 0;
174 
175 	switch (strlen(p)) {
176 	case 10:				/* yy */
177 		lt->tm_year = ATOI2(p);
178 		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
179 			lt->tm_year += 100;
180 		/* FALLTHROUGH */
181 	case 8:					/* mm */
182 		lt->tm_mon = ATOI2(p);
183 		if (lt->tm_mon > 12)
184 			badformat();
185 		--lt->tm_mon;			/* time struct is 0 - 11 */
186 		/* FALLTHROUGH */
187 	case 6:					/* dd */
188 		lt->tm_mday = ATOI2(p);
189 		if (lt->tm_mday > 31)
190 			badformat();
191 		/* FALLTHROUGH */
192 	case 4:					/* hh */
193 		lt->tm_hour = ATOI2(p);
194 		if (lt->tm_hour > 23)
195 			badformat();
196 		/* FALLTHROUGH */
197 	case 2:					/* mm */
198 		lt->tm_min = ATOI2(p);
199 		if (lt->tm_min > 59)
200 			badformat();
201 		break;
202 	default:
203 		badformat();
204 	}
205 
206 	/* convert broken-down time to GMT clock time */
207 	if ((tval = mktime(lt)) == -1)
208 		badformat();
209 
210 	/* set the time */
211 	if (nflag || netsettime(tval)) {
212 		logwtmp("|", "date", "");
213 		tv.tv_sec = tval;
214 		tv.tv_usec = 0;
215 		if (settimeofday(&tv, NULL)) {
216 			perror("date: settimeofday");
217 			exit(1);
218 		}
219 		logwtmp("{", "date", "");
220 	}
221 
222 	if ((p = getlogin()) == NULL)
223 		p = "???";
224 	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
225 }
226 
227 static void
228 badformat()
229 {
230 	warnx("illegal time format");
231 	usage();
232 }
233 
234 static void
235 usage()
236 {
237 	(void)fprintf(stderr,
238 	    "usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]\n");
239 	(void)fprintf(stderr, "            [yy[mm[dd[hh]]]]mm[.ss]]\n");
240 	exit(1);
241 }
242