xref: /netbsd-src/bin/date/date.c (revision cda4f8f6ee55684e8d311b86c99ea59191e6b74f)
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
35 char 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
41 static char sccsid[] = "@(#)date.c	5.5 (Berkeley) 3/18/91";
42 static char rcsid[] = "$Header: /cvsroot/src/bin/date/date.c,v 1.4 1993/06/21 05:18:44 deraadt Exp $";
43 #endif /* not lint */
44 
45 #include <sys/param.h>
46 #include <sys/time.h>
47 #include <sys/file.h>
48 #include <syslog.h>
49 #include <unistd.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <ctype.h>
54 
55 time_t tval;
56 int retval, nflag;
57 
58 main(argc, argv)
59 	int argc;
60 	char **argv;
61 {
62 	extern int optind;
63 	extern char *optarg;
64 	struct timezone tz;
65 	int ch, rflag;
66 	char *format, buf[1024];
67 
68 	tz.tz_dsttime = tz.tz_minuteswest = 0;
69 	rflag = 0;
70 	while ((ch = getopt(argc, argv, "d:nr:ut:")) != EOF)
71 		switch((char)ch) {
72 		case 'd':		/* daylight savings time */
73 			tz.tz_dsttime = atoi(optarg) ? 1 : 0;
74 			break;
75 		case 'n':		/* don't set network */
76 			nflag = 1;
77 			break;
78 		case 'r':		/* user specified seconds */
79 			rflag = 1;
80 			tval = atol(optarg);
81 			break;
82 		case 'u':		/* do everything in GMT */
83 			(void)setenv("TZ", "GMT0", 1);
84 			break;
85 		case 't':		/* minutes west of GMT */
86 					/* error check; don't allow "PST" */
87 			if (isdigit(*optarg)) {
88 				tz.tz_minuteswest = atoi(optarg);
89 				break;
90 			}
91 			/* FALLTHROUGH */
92 		default:
93 			usage();
94 		}
95 	argc -= optind;
96 	argv += optind;
97 
98 	/*
99 	 * If -d or -t, set the timezone or daylight savings time; this
100 	 * doesn't belong here, there kernel should not know about either.
101 	 */
102 	if ((tz.tz_minuteswest || tz.tz_dsttime) &&
103 	    settimeofday((struct timeval *)NULL, &tz)) {
104 		perror("date: settimeofday");
105 		exit(1);
106 	}
107 
108 	if (!rflag && time(&tval) == -1) {
109 		perror("date: time");
110 		exit(1);
111 	}
112 
113 	format = "%a %b %e %H:%M:%S %Z %Y\n";
114 
115 	/* allow the operands in any order */
116 	if (*argv && **argv == '+') {
117 		format = *argv + 1;
118 		++argv;
119 	}
120 
121 	if (*argv) {
122 		setthetime(*argv);
123 		++argv;
124 	}
125 
126 	if (*argv && **argv == '+')
127 		format = *argv + 1;
128 
129 	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
130 	(void)printf("%s", buf);
131 	exit(retval);
132 }
133 
134 #define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
135 setthetime(p)
136 	register char *p;
137 {
138 	register struct tm *lt;
139 	struct timeval tv;
140 	int dot;
141 	char *t;
142 
143 	for (t = p, dot = 0; *t; ++t)
144 		if (!isdigit(*t) && (*t != '.' || dot++))
145 			badformat();
146 
147 	lt = localtime(&tval);
148 
149 	if (t = index(p, '.')) {		/* .ss */
150 		*t++ = '\0';
151 		lt->tm_sec = ATOI2(t);
152 		if (lt->tm_sec > 61)
153 			badformat();
154 	} else
155 		lt->tm_sec = 0;
156 
157 	for (t = p; *t; ++t)
158 		if (!isdigit(*t))
159 			badformat();
160 
161 	switch (strlen(p)) {
162 	case 10:				/* yy */
163 		lt->tm_year = ATOI2(p);
164 		if (lt->tm_year < 69)		/* hack for 2000 ;-} */
165 			lt->tm_year += 100;
166 		/* FALLTHROUGH */
167 	case 8:					/* mm */
168 		lt->tm_mon = ATOI2(p);
169 		if (lt->tm_mon > 12)
170 			badformat();
171 		--lt->tm_mon;			/* time struct is 0 - 11 */
172 		/* FALLTHROUGH */
173 	case 6:					/* dd */
174 		lt->tm_mday = ATOI2(p);
175 		if (lt->tm_mday > 31)
176 			badformat();
177 		/* FALLTHROUGH */
178 	case 4:					/* hh */
179 		lt->tm_hour = ATOI2(p);
180 		if (lt->tm_hour > 23)
181 			badformat();
182 		/* FALLTHROUGH */
183 	case 2:					/* mm */
184 		lt->tm_min = ATOI2(p);
185 		if (lt->tm_min > 59)
186 			badformat();
187 		break;
188 	default:
189 		badformat();
190 	}
191 
192 	/* convert broken-down time to GMT clock time */
193 	if ((tval = mktime(lt)) == -1)
194 		badformat();
195 
196 	if (!(p = getlogin()))			/* single-user or no tty */
197 		p = "root";
198 	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
199 
200 	/* set the time */
201 	if (nflag || netsettime(tval)) {
202 		logwtmp("|", "date", "");
203 		tv.tv_sec = tval;
204 		tv.tv_usec = 0;
205 		if (settimeofday(&tv, (struct timezone *)NULL)) {
206 			perror("date: settimeofday");
207 			exit(1);
208 		}
209 		logwtmp("{", "date", "");
210 	}
211 }
212 
213 badformat()
214 {
215 	(void)fprintf(stderr, "date: illegal time format.\n");
216 	usage();
217 }
218 
219 usage()
220 {
221 	(void)fprintf(stderr,
222 	    "usage: date [-nu] [-d dst] [-r seconds] [-t west] [+format]\n");
223 	(void)fprintf(stderr, "            [yy[mm[dd[hh]]]]mm[.ss]]\n");
224 	exit(1);
225 }
226