xref: /freebsd/bin/date/date.c (revision 276da39af92f48350aa01091a2b8b3e735217eea)
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 #include <sys/stat.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <locale.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <syslog.h>
56 #include <unistd.h>
57 #include <utmpx.h>
58 
59 #include "extern.h"
60 #include "vary.h"
61 
62 #ifndef	TM_YEAR_BASE
63 #define	TM_YEAR_BASE	1900
64 #endif
65 
66 static time_t tval;
67 int retval;
68 
69 static void setthetime(const char *, const char *, int, int);
70 static void badformat(void);
71 static void usage(void);
72 
73 static const char *rfc2822_format = "%a, %d %b %Y %T %z";
74 
75 int
76 main(int argc, char *argv[])
77 {
78 	struct timezone tz;
79 	int ch, rflag;
80 	int jflag, nflag, Rflag;
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 	struct stat sb;
90 
91 	v = NULL;
92 	fmt = NULL;
93 	(void) setlocale(LC_TIME, "");
94 	tz.tz_dsttime = tz.tz_minuteswest = 0;
95 	rflag = 0;
96 	jflag = nflag = Rflag = 0;
97 	set_timezone = 0;
98 	while ((ch = getopt(argc, argv, "d:f:jnRr:t:uv:")) != -1)
99 		switch((char)ch) {
100 		case 'd':		/* daylight savings time */
101 			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
102 			if (endptr == optarg || *endptr != '\0')
103 				usage();
104 			set_timezone = 1;
105 			break;
106 		case 'f':
107 			fmt = optarg;
108 			break;
109 		case 'j':
110 			jflag = 1;	/* don't set time */
111 			break;
112 		case 'n':		/* don't set network */
113 			nflag = 1;
114 			break;
115 		case 'R':		/* RFC 2822 datetime format */
116 			Rflag = 1;
117 			break;
118 		case 'r':		/* user specified seconds */
119 			rflag = 1;
120 			tval = strtoq(optarg, &tmp, 0);
121 			if (*tmp != 0) {
122 				if (stat(optarg, &sb) == 0)
123 					tval = sb.st_mtim.tv_sec;
124 				else
125 					usage();
126 			}
127 			break;
128 		case 't':		/* minutes west of UTC */
129 					/* error check; don't allow "PST" */
130 			tz.tz_minuteswest = strtol(optarg, &endptr, 10);
131 			if (endptr == optarg || *endptr != '\0')
132 				usage();
133 			set_timezone = 1;
134 			break;
135 		case 'u':		/* do everything in UTC */
136 			(void)setenv("TZ", "UTC0", 1);
137 			break;
138 		case 'v':
139 			v = vary_append(v, optarg);
140 			break;
141 		default:
142 			usage();
143 		}
144 	argc -= optind;
145 	argv += optind;
146 
147 	/*
148 	 * If -d or -t, set the timezone or daylight savings time; this
149 	 * doesn't belong here; the kernel should not know about either.
150 	 */
151 	if (set_timezone && settimeofday(NULL, &tz) != 0)
152 		err(1, "settimeofday (timezone)");
153 
154 	if (!rflag && time(&tval) == -1)
155 		err(1, "time");
156 
157 	format = "%+";
158 
159 	if (Rflag)
160 		format = rfc2822_format;
161 
162 	/* allow the operands in any order */
163 	if (*argv && **argv == '+') {
164 		format = *argv + 1;
165 		++argv;
166 	}
167 
168 	if (*argv) {
169 		setthetime(fmt, *argv, jflag, nflag);
170 		++argv;
171 	} else if (fmt != NULL)
172 		usage();
173 
174 	if (*argv && **argv == '+')
175 		format = *argv + 1;
176 
177 	lt = *localtime(&tval);
178 	badv = vary_apply(v, &lt);
179 	if (badv) {
180 		fprintf(stderr, "%s: Cannot apply date adjustment\n",
181 			badv->arg);
182 		vary_destroy(v);
183 		usage();
184 	}
185 	vary_destroy(v);
186 
187 	if (format == rfc2822_format)
188 		/*
189 		 * When using RFC 2822 datetime format, don't honor the
190 		 * locale.
191 		 */
192 		setlocale(LC_TIME, "C");
193 
194 	(void)strftime(buf, sizeof(buf), format, &lt);
195 	(void)printf("%s\n", buf);
196 	if (fflush(stdout))
197 		err(1, "stdout");
198 	exit(retval);
199 }
200 
201 #define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
202 
203 static void
204 setthetime(const char *fmt, const char *p, int jflag, int nflag)
205 {
206 	struct utmpx utx;
207 	struct tm *lt;
208 	struct timeval tv;
209 	const char *dot, *t;
210 	int century;
211 
212 	lt = localtime(&tval);
213 	lt->tm_isdst = -1;		/* divine correct DST */
214 
215 	if (fmt != NULL) {
216 		t = strptime(p, fmt, lt);
217 		if (t == NULL) {
218 			fprintf(stderr, "Failed conversion of ``%s''"
219 				" using format ``%s''\n", p, fmt);
220 			badformat();
221 		} else if (*t != '\0')
222 			fprintf(stderr, "Warning: Ignoring %ld extraneous"
223 				" characters in date string (%s)\n",
224 				(long) strlen(t), t);
225 	} else {
226 		for (t = p, dot = NULL; *t; ++t) {
227 			if (isdigit(*t))
228 				continue;
229 			if (*t == '.' && dot == NULL) {
230 				dot = t;
231 				continue;
232 			}
233 			badformat();
234 		}
235 
236 		if (dot != NULL) {			/* .ss */
237 			dot++; /* *dot++ = '\0'; */
238 			if (strlen(dot) != 2)
239 				badformat();
240 			lt->tm_sec = ATOI2(dot);
241 			if (lt->tm_sec > 61)
242 				badformat();
243 		} else
244 			lt->tm_sec = 0;
245 
246 		century = 0;
247 		/* if p has a ".ss" field then let's pretend it's not there */
248 		switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
249 		case 12:				/* cc */
250 			lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
251 			century = 1;
252 			/* FALLTHROUGH */
253 		case 10:				/* yy */
254 			if (century)
255 				lt->tm_year += ATOI2(p);
256 			else {
257 				lt->tm_year = ATOI2(p);
258 				if (lt->tm_year < 69)	/* hack for 2000 ;-} */
259 					lt->tm_year += 2000 - TM_YEAR_BASE;
260 				else
261 					lt->tm_year += 1900 - TM_YEAR_BASE;
262 			}
263 			/* FALLTHROUGH */
264 		case 8:					/* mm */
265 			lt->tm_mon = ATOI2(p);
266 			if (lt->tm_mon > 12)
267 				badformat();
268 			--lt->tm_mon;		/* time struct is 0 - 11 */
269 			/* FALLTHROUGH */
270 		case 6:					/* dd */
271 			lt->tm_mday = ATOI2(p);
272 			if (lt->tm_mday > 31)
273 				badformat();
274 			/* FALLTHROUGH */
275 		case 4:					/* HH */
276 			lt->tm_hour = ATOI2(p);
277 			if (lt->tm_hour > 23)
278 				badformat();
279 			/* FALLTHROUGH */
280 		case 2:					/* MM */
281 			lt->tm_min = ATOI2(p);
282 			if (lt->tm_min > 59)
283 				badformat();
284 			break;
285 		default:
286 			badformat();
287 		}
288 	}
289 
290 	/* convert broken-down time to GMT clock time */
291 	if ((tval = mktime(lt)) == -1)
292 		errx(1, "nonexistent time");
293 
294 	if (!jflag) {
295 		/* set the time */
296 		if (nflag || netsettime(tval)) {
297 			utx.ut_type = OLD_TIME;
298 			(void)gettimeofday(&utx.ut_tv, NULL);
299 			pututxline(&utx);
300 			tv.tv_sec = tval;
301 			tv.tv_usec = 0;
302 			if (settimeofday(&tv, NULL) != 0)
303 				err(1, "settimeofday (timeval)");
304 			utx.ut_type = NEW_TIME;
305 			(void)gettimeofday(&utx.ut_tv, NULL);
306 			pututxline(&utx);
307 		}
308 
309 		if ((p = getlogin()) == NULL)
310 			p = "???";
311 		syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
312 	}
313 }
314 
315 static void
316 badformat(void)
317 {
318 	warnx("illegal time format");
319 	usage();
320 }
321 
322 static void
323 usage(void)
324 {
325 	(void)fprintf(stderr, "%s\n%s\n",
326 	    "usage: date [-jnRu] [-d dst] [-r seconds] [-t west] "
327 	    "[-v[+|-]val[ymwdHMS]] ... ",
328 	    "            "
329 	    "[-f fmt date | [[[[[cc]yy]mm]dd]HH]MM[.ss]] [+format]");
330 	exit(1);
331 }
332