xref: /freebsd/bin/date/date.c (revision 68e7a217f8019b955f87547f218e95ab237597af)
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 <locale.h>
54 #include <libutil.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <syslog.h>
59 #include <unistd.h>
60 
61 #include "extern.h"
62 #include "vary.h"
63 
64 #ifndef	TM_YEAR_BASE
65 #define	TM_YEAR_BASE	1900
66 #endif
67 
68 time_t tval;
69 int retval;
70 
71 static void setthetime(const char *, const char *, int, int);
72 static void badformat(void);
73 static void usage(void);
74 
75 int
76 main(int argc, char *argv[])
77 {
78 	struct timezone tz;
79 	int ch, rflag;
80 	int jflag, nflag;
81 	const char *format;
82 	char buf[1024];
83 	char *endptr, *fmt;
84 	char *tmp;
85 	int set_timezone;
86 	struct vary *v;
87 	const struct vary *badv;
88 	struct tm lt;
89 
90 	v = NULL;
91 	fmt = NULL;
92 	(void) setlocale(LC_TIME, "");
93 	tz.tz_dsttime = tz.tz_minuteswest = 0;
94 	rflag = 0;
95 	jflag = nflag = 0;
96 	set_timezone = 0;
97 	while ((ch = getopt(argc, argv, "d:f:jnr:t:uv:")) != -1)
98 		switch((char)ch) {
99 		case 'd':		/* daylight savings time */
100 			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
101 			if (endptr == optarg || *endptr != '\0')
102 				usage();
103 			set_timezone = 1;
104 			break;
105 		case 'f':
106 			fmt = optarg;
107 			break;
108 		case 'j':
109 			jflag = 1;	/* don't set time */
110 			break;
111 		case 'n':		/* don't set network */
112 			nflag = 1;
113 			break;
114 		case 'r':		/* user specified seconds */
115 			rflag = 1;
116 			tval = strtoq(optarg, &tmp, 0);
117 			if (*tmp != 0)
118 				usage();
119 			break;
120 		case 't':		/* minutes west of UTC */
121 					/* error check; don't allow "PST" */
122 			tz.tz_minuteswest = strtol(optarg, &endptr, 10);
123 			if (endptr == optarg || *endptr != '\0')
124 				usage();
125 			set_timezone = 1;
126 			break;
127 		case 'u':		/* do everything in UTC */
128 			(void)setenv("TZ", "UTC0", 1);
129 			break;
130 		case 'v':
131 			v = vary_append(v, optarg);
132 			break;
133 		default:
134 			usage();
135 		}
136 	argc -= optind;
137 	argv += optind;
138 
139 	/*
140 	 * If -d or -t, set the timezone or daylight savings time; this
141 	 * doesn't belong here; the kernel should not know about either.
142 	 */
143 	if (set_timezone && settimeofday((struct timeval *)NULL, &tz))
144 		err(1, "settimeofday (timezone)");
145 
146 	if (!rflag && time(&tval) == -1)
147 		err(1, "time");
148 
149 	format = "%+";
150 
151 	/* allow the operands in any order */
152 	if (*argv && **argv == '+') {
153 		format = *argv + 1;
154 		++argv;
155 	}
156 
157 	if (*argv) {
158 		setthetime(fmt, *argv, jflag, nflag);
159 		++argv;
160 	} else if (fmt != NULL)
161 		usage();
162 
163 	if (*argv && **argv == '+')
164 		format = *argv + 1;
165 
166 	lt = *localtime(&tval);
167 	badv = vary_apply(v, &lt);
168 	if (badv) {
169 		fprintf(stderr, "%s: Cannot apply date adjustment\n",
170 			badv->arg);
171 		vary_destroy(v);
172 		usage();
173 	}
174 	vary_destroy(v);
175 	(void)strftime(buf, sizeof(buf), format, &lt);
176 	(void)printf("%s\n", buf);
177 	exit(retval);
178 }
179 
180 #define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
181 
182 void
183 setthetime(const char *fmt, const char *p, int jflag, int nflag)
184 {
185 	struct tm *lt;
186 	struct timeval tv;
187 	const char *dot, *t;
188 	int century;
189 
190 	if (fmt != NULL) {
191 		lt = localtime(&tval);
192 		t = strptime(p, fmt, lt);
193 		if (t == NULL) {
194 			fprintf(stderr, "Failed conversion of ``%s''"
195 				" using format ``%s''\n", p, fmt);
196 			badformat();
197 		} else if (*t != '\0')
198 			fprintf(stderr, "Warning: Ignoring %ld extraneous"
199 				" characters in date string (%s)\n",
200 				(long) strlen(t), t);
201 	} else {
202 		for (t = p, dot = NULL; *t; ++t) {
203 			if (isdigit(*t))
204 				continue;
205 			if (*t == '.' && dot == NULL) {
206 				dot = t;
207 				continue;
208 			}
209 			badformat();
210 		}
211 
212 		lt = localtime(&tval);
213 
214 		if (dot != NULL) {			/* .ss */
215 			dot++; /* *dot++ = '\0'; */
216 			if (strlen(dot) != 2)
217 				badformat();
218 			lt->tm_sec = ATOI2(dot);
219 			if (lt->tm_sec > 61)
220 				badformat();
221 		} else
222 			lt->tm_sec = 0;
223 
224 		century = 0;
225 		/* if p has a ".ss" field then let's pretend it's not there */
226 		switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
227 		case 12:				/* cc */
228 			lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
229 			century = 1;
230 			/* FALLTHROUGH */
231 		case 10:				/* yy */
232 			if (century)
233 				lt->tm_year += ATOI2(p);
234 			else {				/* hack for 2000 ;-} */
235 				lt->tm_year = ATOI2(p);
236 				if (lt->tm_year < 69)
237 					lt->tm_year += 2000 - TM_YEAR_BASE;
238 				else
239 					lt->tm_year += 1900 - TM_YEAR_BASE;
240 			}
241 			/* FALLTHROUGH */
242 		case 8:					/* mm */
243 			lt->tm_mon = ATOI2(p);
244 			if (lt->tm_mon > 12)
245 				badformat();
246 			--lt->tm_mon;		/* time struct is 0 - 11 */
247 			/* FALLTHROUGH */
248 		case 6:					/* dd */
249 			lt->tm_mday = ATOI2(p);
250 			if (lt->tm_mday > 31)
251 				badformat();
252 			/* FALLTHROUGH */
253 		case 4:					/* HH */
254 			lt->tm_hour = ATOI2(p);
255 			if (lt->tm_hour > 23)
256 				badformat();
257 			/* FALLTHROUGH */
258 		case 2:					/* MM */
259 			lt->tm_min = ATOI2(p);
260 			if (lt->tm_min > 59)
261 				badformat();
262 			break;
263 		default:
264 			badformat();
265 		}
266 	}
267 
268 	/* Let mktime() decide whether summer time is in effect. */
269 	lt->tm_isdst = -1;
270 
271 	/* convert broken-down time to GMT clock time */
272 	if ((tval = mktime(lt)) == -1)
273 		errx(1, "nonexistent time");
274 
275 	if (!jflag) {
276 		/* set the time */
277 		if (nflag || netsettime(tval)) {
278 			logwtmp("|", "date", "");
279 			tv.tv_sec = tval;
280 			tv.tv_usec = 0;
281 			if (settimeofday(&tv, (struct timezone *)NULL))
282 				err(1, "settimeofday (timeval)");
283 			logwtmp("{", "date", "");
284 		}
285 
286 		if ((p = getlogin()) == NULL)
287 			p = "???";
288 		syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
289 	}
290 }
291 
292 static void
293 badformat(void)
294 {
295 	warnx("illegal time format");
296 	usage();
297 }
298 
299 static void
300 usage(void)
301 {
302 	(void)fprintf(stderr, "%s\n%s\n",
303 	    "usage: date [-jnu] [-d dst] [-r seconds] [-t west] "
304 	    "[-v[+|-]val[ymwdHMS]] ... ",
305 	    "            "
306 	    "[-f fmt date | [[[[[cc]yy]mm]dd]HH]MM[.ss]] [+format]");
307 	exit(1);
308 }
309