xref: /freebsd/bin/date/date.c (revision fcb560670601b2a4d87bb31d7531c8dcc37ee71b)
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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static char const copyright[] =
32 "@(#) Copyright (c) 1985, 1987, 1988, 1993\n\
33 	The Regents of the University of California.  All rights reserved.\n";
34 #endif /* not lint */
35 
36 #if 0
37 #ifndef lint
38 static char sccsid[] = "@(#)date.c	8.2 (Berkeley) 4/28/95";
39 #endif /* not lint */
40 #endif
41 
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44 
45 #include <sys/param.h>
46 #include <sys/time.h>
47 
48 #include <ctype.h>
49 #include <err.h>
50 #include <locale.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <syslog.h>
55 #include <unistd.h>
56 #include <utmpx.h>
57 
58 #include "extern.h"
59 #include "vary.h"
60 
61 #ifndef	TM_YEAR_BASE
62 #define	TM_YEAR_BASE	1900
63 #endif
64 
65 static time_t tval;
66 int retval;
67 
68 static void setthetime(const char *, const char *, int, int);
69 static void badformat(void);
70 static void usage(void);
71 
72 static const char *rfc2822_format = "%a, %d %b %Y %T %z";
73 
74 int
75 main(int argc, char *argv[])
76 {
77 	struct timezone tz;
78 	int ch, rflag;
79 	int jflag, nflag, Rflag;
80 	const char *format;
81 	char buf[1024];
82 	char *endptr, *fmt;
83 	char *tmp;
84 	int set_timezone;
85 	struct vary *v;
86 	const struct vary *badv;
87 	struct tm lt;
88 
89 	v = NULL;
90 	fmt = NULL;
91 	(void) setlocale(LC_TIME, "");
92 	tz.tz_dsttime = tz.tz_minuteswest = 0;
93 	rflag = 0;
94 	jflag = nflag = Rflag = 0;
95 	set_timezone = 0;
96 	while ((ch = getopt(argc, argv, "d:f:jnRr:t:uv:")) != -1)
97 		switch((char)ch) {
98 		case 'd':		/* daylight savings time */
99 			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
100 			if (endptr == optarg || *endptr != '\0')
101 				usage();
102 			set_timezone = 1;
103 			break;
104 		case 'f':
105 			fmt = optarg;
106 			break;
107 		case 'j':
108 			jflag = 1;	/* don't set time */
109 			break;
110 		case 'n':		/* don't set network */
111 			nflag = 1;
112 			break;
113 		case 'R':		/* RFC 2822 datetime format */
114 			Rflag = 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(NULL, &tz) != 0)
146 		err(1, "settimeofday (timezone)");
147 
148 	if (!rflag && time(&tval) == -1)
149 		err(1, "time");
150 
151 	format = "%+";
152 
153 	if (Rflag)
154 		format = rfc2822_format;
155 
156 	/* allow the operands in any order */
157 	if (*argv && **argv == '+') {
158 		format = *argv + 1;
159 		++argv;
160 	}
161 
162 	if (*argv) {
163 		setthetime(fmt, *argv, jflag, nflag);
164 		++argv;
165 	} else if (fmt != NULL)
166 		usage();
167 
168 	if (*argv && **argv == '+')
169 		format = *argv + 1;
170 
171 	lt = *localtime(&tval);
172 	badv = vary_apply(v, &lt);
173 	if (badv) {
174 		fprintf(stderr, "%s: Cannot apply date adjustment\n",
175 			badv->arg);
176 		vary_destroy(v);
177 		usage();
178 	}
179 	vary_destroy(v);
180 
181 	if (format == rfc2822_format)
182 		/*
183 		 * When using RFC 2822 datetime format, don't honor the
184 		 * locale.
185 		 */
186 		setlocale(LC_TIME, "C");
187 
188 	(void)strftime(buf, sizeof(buf), format, &lt);
189 	(void)printf("%s\n", buf);
190 	if (fflush(stdout))
191 		err(1, "stdout");
192 	exit(retval);
193 }
194 
195 #define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
196 
197 static void
198 setthetime(const char *fmt, const char *p, int jflag, int nflag)
199 {
200 	struct utmpx utx;
201 	struct tm *lt;
202 	struct timeval tv;
203 	const char *dot, *t;
204 	int century;
205 
206 	lt = localtime(&tval);
207 	lt->tm_isdst = -1;		/* divine correct DST */
208 
209 	if (fmt != NULL) {
210 		t = strptime(p, fmt, lt);
211 		if (t == NULL) {
212 			fprintf(stderr, "Failed conversion of ``%s''"
213 				" using format ``%s''\n", p, fmt);
214 			badformat();
215 		} else if (*t != '\0')
216 			fprintf(stderr, "Warning: Ignoring %ld extraneous"
217 				" characters in date string (%s)\n",
218 				(long) strlen(t), t);
219 	} else {
220 		for (t = p, dot = NULL; *t; ++t) {
221 			if (isdigit(*t))
222 				continue;
223 			if (*t == '.' && dot == NULL) {
224 				dot = t;
225 				continue;
226 			}
227 			badformat();
228 		}
229 
230 		if (dot != NULL) {			/* .ss */
231 			dot++; /* *dot++ = '\0'; */
232 			if (strlen(dot) != 2)
233 				badformat();
234 			lt->tm_sec = ATOI2(dot);
235 			if (lt->tm_sec > 61)
236 				badformat();
237 		} else
238 			lt->tm_sec = 0;
239 
240 		century = 0;
241 		/* if p has a ".ss" field then let's pretend it's not there */
242 		switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
243 		case 12:				/* cc */
244 			lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
245 			century = 1;
246 			/* FALLTHROUGH */
247 		case 10:				/* yy */
248 			if (century)
249 				lt->tm_year += ATOI2(p);
250 			else {
251 				lt->tm_year = ATOI2(p);
252 				if (lt->tm_year < 69)	/* hack for 2000 ;-} */
253 					lt->tm_year += 2000 - TM_YEAR_BASE;
254 				else
255 					lt->tm_year += 1900 - TM_YEAR_BASE;
256 			}
257 			/* FALLTHROUGH */
258 		case 8:					/* mm */
259 			lt->tm_mon = ATOI2(p);
260 			if (lt->tm_mon > 12)
261 				badformat();
262 			--lt->tm_mon;		/* time struct is 0 - 11 */
263 			/* FALLTHROUGH */
264 		case 6:					/* dd */
265 			lt->tm_mday = ATOI2(p);
266 			if (lt->tm_mday > 31)
267 				badformat();
268 			/* FALLTHROUGH */
269 		case 4:					/* HH */
270 			lt->tm_hour = ATOI2(p);
271 			if (lt->tm_hour > 23)
272 				badformat();
273 			/* FALLTHROUGH */
274 		case 2:					/* MM */
275 			lt->tm_min = ATOI2(p);
276 			if (lt->tm_min > 59)
277 				badformat();
278 			break;
279 		default:
280 			badformat();
281 		}
282 	}
283 
284 	/* convert broken-down time to GMT clock time */
285 	if ((tval = mktime(lt)) == -1)
286 		errx(1, "nonexistent time");
287 
288 	if (!jflag) {
289 		/* set the time */
290 		if (nflag || netsettime(tval)) {
291 			utx.ut_type = OLD_TIME;
292 			(void)gettimeofday(&utx.ut_tv, NULL);
293 			pututxline(&utx);
294 			tv.tv_sec = tval;
295 			tv.tv_usec = 0;
296 			if (settimeofday(&tv, NULL) != 0)
297 				err(1, "settimeofday (timeval)");
298 			utx.ut_type = NEW_TIME;
299 			(void)gettimeofday(&utx.ut_tv, NULL);
300 			pututxline(&utx);
301 		}
302 
303 		if ((p = getlogin()) == NULL)
304 			p = "???";
305 		syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
306 	}
307 }
308 
309 static void
310 badformat(void)
311 {
312 	warnx("illegal time format");
313 	usage();
314 }
315 
316 static void
317 usage(void)
318 {
319 	(void)fprintf(stderr, "%s\n%s\n",
320 	    "usage: date [-jnRu] [-d dst] [-r seconds] [-t west] "
321 	    "[-v[+|-]val[ymwdHMS]] ... ",
322 	    "            "
323 	    "[-f fmt date | [[[[[cc]yy]mm]dd]HH]MM[.ss]] [+format]");
324 	exit(1);
325 }
326