xref: /freebsd/bin/date/date.c (revision 17d6c636720d00f77e5d098daf4c278f89d84f7b)
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 const 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 #if 0
42 static char sccsid[] = "@(#)date.c	8.2 (Berkeley) 4/28/95";
43 #endif
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #include <sys/param.h>
49 #include <sys/time.h>
50 
51 #include <ctype.h>
52 #include <err.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <syslog.h>
57 #include <unistd.h>
58 #include <locale.h>
59 
60 #include "extern.h"
61 #include "vary.h"
62 
63 #ifndef	TM_YEAR_BASE
64 #define	TM_YEAR_BASE	1900
65 #endif
66 
67 time_t tval;
68 int retval;
69 
70 static void setthetime __P((const char *, const char *, int, int));
71 static void badformat __P((void));
72 static void usage __P((void));
73 
74 int logwtmp __P((char *, char *, char *));
75 
76 int
77 main(argc, argv)
78 	int argc;
79 	char **argv;
80 {
81 	struct timezone tz;
82 	int ch, rflag;
83 	int jflag, nflag;
84 	char *format, buf[1024];
85 	char *endptr, *fmt;
86 	char *tmp;
87 	int set_timezone;
88 	struct vary *v;
89 	const struct vary *badv;
90 	struct tm lt;
91 
92 	v = NULL;
93 	fmt = NULL;
94 	(void) setlocale(LC_TIME, "");
95 	tz.tz_dsttime = tz.tz_minuteswest = 0;
96 	rflag = 0;
97 	jflag = nflag = 0;
98 	set_timezone = 0;
99 	while ((ch = getopt(argc, argv, "d:f:jnr:t:uv:")) != -1)
100 		switch((char)ch) {
101 		case 'd':		/* daylight savings time */
102 			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
103 			if (endptr == optarg || *endptr != '\0')
104 				usage();
105 			set_timezone = 1;
106 			break;
107 		case 'f':
108 			fmt = optarg;
109 			break;
110 		case 'j':
111 			jflag = 1;	/* don't set time */
112 			break;
113 		case 'n':		/* don't set network */
114 			nflag = 1;
115 			break;
116 		case 'r':		/* user specified seconds */
117 			rflag = 1;
118 			tval = strtoq(optarg, &tmp, 0);
119 			if (*tmp != 0)
120 				usage();
121 			break;
122 		case 't':		/* minutes west of UTC */
123 					/* error check; don't allow "PST" */
124 			tz.tz_minuteswest = strtol(optarg, &endptr, 10);
125 			if (endptr == optarg || *endptr != '\0')
126 				usage();
127 			set_timezone = 1;
128 			break;
129 		case 'u':		/* do everything in UTC */
130 			(void)setenv("TZ", "UTC0", 1);
131 			break;
132 		case 'v':
133 			v = vary_append(v, optarg);
134 			break;
135 		default:
136 			usage();
137 		}
138 	argc -= optind;
139 	argv += optind;
140 
141 	/*
142 	 * If -d or -t, set the timezone or daylight savings time; this
143 	 * doesn't belong here; the kernel should not know about either.
144 	 */
145 	if (set_timezone && settimeofday((struct timeval *)NULL, &tz))
146 		err(1, "settimeofday (timezone)");
147 
148 	if (!rflag && time(&tval) == -1)
149 		err(1, "time");
150 
151 	format = "%+";
152 
153 	/* allow the operands in any order */
154 	if (*argv && **argv == '+') {
155 		format = *argv + 1;
156 		++argv;
157 	}
158 
159 	if (*argv) {
160 		setthetime(fmt, *argv, jflag, nflag);
161 		++argv;
162 	} else if (fmt != NULL)
163 		usage();
164 
165 	if (*argv && **argv == '+')
166 		format = *argv + 1;
167 
168 	lt = *localtime(&tval);
169 	badv = vary_apply(v, &lt);
170 	if (badv) {
171 		fprintf(stderr, "%s: Cannot apply date adjustment\n",
172 			badv->arg);
173 		vary_destroy(v);
174 		usage();
175 	}
176 	vary_destroy(v);
177 	(void)strftime(buf, sizeof(buf), format, &lt);
178 	(void)printf("%s\n", buf);
179 	exit(retval);
180 }
181 
182 #define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
183 
184 void
185 setthetime(fmt, p, jflag, nflag)
186 	const char *fmt;
187 	register const char *p;
188 	int jflag, nflag;
189 {
190 	register struct tm *lt;
191 	struct timeval tv;
192 	const char *dot, *t;
193 	int century;
194 
195 	if (fmt != NULL) {
196 		lt = localtime(&tval);
197 		t = strptime(p, fmt, lt);
198 		if (t == NULL) {
199 			fprintf(stderr, "Failed conversion of ``%s''"
200 				" using format ``%s''\n", p, fmt);
201 			badformat();
202 		} else if (*t != '\0')
203 			fprintf(stderr, "Warning: Ignoring %ld extraneous"
204 				" characters in date string (%s)\n",
205 				(long) strlen(t), t);
206 	} else {
207 		for (t = p, dot = NULL; *t; ++t) {
208 			if (isdigit(*t))
209 				continue;
210 			if (*t == '.' && dot == NULL) {
211 				dot = t;
212 				continue;
213 			}
214 			badformat();
215 		}
216 
217 		lt = localtime(&tval);
218 
219 		if (dot != NULL) {			/* .ss */
220 			dot++; /* *dot++ = '\0'; */
221 			if (strlen(dot) != 2)
222 				badformat();
223 			lt->tm_sec = ATOI2(dot);
224 			if (lt->tm_sec > 61)
225 				badformat();
226 		} else
227 			lt->tm_sec = 0;
228 
229 		century = 0;
230 		/* if p has a ".ss" field then let's pretend it's not there */
231 		switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
232 		case 12:				/* cc */
233 			lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
234 			century = 1;
235 			/* FALLTHROUGH */
236 		case 10:				/* yy */
237 			if (century)
238 				lt->tm_year += ATOI2(p);
239 			else {				/* hack for 2000 ;-} */
240 				lt->tm_year = ATOI2(p);
241 				if (lt->tm_year < 69)
242 					lt->tm_year += 2000 - TM_YEAR_BASE;
243 				else
244 					lt->tm_year += 1900 - TM_YEAR_BASE;
245 			}
246 			/* FALLTHROUGH */
247 		case 8:					/* mm */
248 			lt->tm_mon = ATOI2(p);
249 			if (lt->tm_mon > 12)
250 				badformat();
251 			--lt->tm_mon;		/* time struct is 0 - 11 */
252 			/* FALLTHROUGH */
253 		case 6:					/* dd */
254 			lt->tm_mday = ATOI2(p);
255 			if (lt->tm_mday > 31)
256 				badformat();
257 			/* FALLTHROUGH */
258 		case 4:					/* HH */
259 			lt->tm_hour = ATOI2(p);
260 			if (lt->tm_hour > 23)
261 				badformat();
262 			/* FALLTHROUGH */
263 		case 2:					/* MM */
264 			lt->tm_min = ATOI2(p);
265 			if (lt->tm_min > 59)
266 				badformat();
267 			break;
268 		default:
269 			badformat();
270 		}
271 	}
272 
273 	/* Let mktime() decide whether summer time is in effect. */
274 	lt->tm_isdst = -1;
275 
276 	/* convert broken-down time to GMT clock time */
277 	if ((tval = mktime(lt)) == -1)
278 		errx(1, "nonexistent time");
279 
280 	if (!jflag) {
281 		/* set the time */
282 		if (nflag || netsettime(tval)) {
283 			logwtmp("|", "date", "");
284 			tv.tv_sec = tval;
285 			tv.tv_usec = 0;
286 			if (settimeofday(&tv, (struct timezone *)NULL))
287 				err(1, "settimeofday (timeval)");
288 			logwtmp("{", "date", "");
289 		}
290 
291 		if ((p = getlogin()) == NULL)
292 			p = "???";
293 		syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
294 	}
295 }
296 
297 static void
298 badformat()
299 {
300 	warnx("illegal time format");
301 	usage();
302 }
303 
304 static void
305 usage()
306 {
307 	(void)fprintf(stderr, "%s\n%s\n",
308 	    "usage: date [-jnu] [-d dst] [-r seconds] [-t west] "
309 	    "[-v[+|-]val[ymwdHMS]] ... ",
310 	    "            "
311 	    "[-f fmt date | [[[[[cc]yy]mm]dd]HH]MM[.ss]] [+format]");
312 	exit(1);
313 }
314