xref: /dragonfly/bin/date/date.c (revision 6693db17)
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  * @(#) Copyright (c) 1985, 1987, 1988, 1993 The Regents of the University of California.  All rights reserved.
34  * @(#)date.c	8.2 (Berkeley) 4/28/95
35  * $FreeBSD: src/bin/date/date.c,v 1.47 2005/01/10 08:39:21 imp Exp $
36  * $DragonFly: src/bin/date/date.c,v 1.14 2006/01/12 13:43:10 corecode Exp $
37  */
38 
39 #include <sys/param.h>
40 #include <sys/time.h>
41 
42 #include <ctype.h>
43 #include <err.h>
44 #include <langinfo.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <syslog.h>
49 #include <unistd.h>
50 #include <locale.h>
51 #include <libutil.h>
52 
53 #include "extern.h"
54 #include "vary.h"
55 
56 #ifndef	TM_YEAR_BASE
57 #define	TM_YEAR_BASE	1900
58 #endif
59 
60 static time_t tval;
61 int retval;
62 
63 static void setthetime(const char *, const char *, int, int);
64 static void badformat(void);
65 static void usage(void);
66 
67 int
68 main(int argc, char **argv)
69 {
70 	struct timezone tz;
71 	int ch, rflag;
72 	int jflag, nflag;
73 	const char *format;
74 	char buf[1024];
75 	char *endptr, *fmt;
76 	char *tmp;
77 	int set_timezone;
78 	struct vary *v;
79 	const struct vary *badv;
80 	struct tm lt;
81 
82 	v = NULL;
83 	fmt = NULL;
84 	setlocale(LC_TIME, "");
85 	tz.tz_dsttime = tz.tz_minuteswest = 0;
86 	rflag = 0;
87 	jflag = nflag = 0;
88 	set_timezone = 0;
89 	while ((ch = getopt(argc, argv, "d:f:jnr:t:uv:")) != -1)
90 		switch(ch) {
91 		case 'd':		/* daylight savings time */
92 			tz.tz_dsttime = strtol(optarg, &endptr, 10) ? 1 : 0;
93 			if (endptr == optarg || *endptr != '\0')
94 				usage();
95 			set_timezone = 1;
96 			break;
97 		case 'f':
98 			fmt = optarg;
99 			break;
100 		case 'j':
101 			jflag = 1;	/* don't set time */
102 			break;
103 		case 'n':		/* don't set network */
104 			nflag = 1;
105 			break;
106 		case 'r':		/* user specified seconds */
107 			rflag = 1;
108 			tval = strtoll(optarg, &tmp, 0);
109 			if (*tmp != 0)
110 				usage();
111 			break;
112 		case 't':		/* minutes west of UTC */
113 					/* error check; don't allow "PST" */
114 			tz.tz_minuteswest = strtol(optarg, &endptr, 10);
115 			if (endptr == optarg || *endptr != '\0')
116 				usage();
117 			set_timezone = 1;
118 			break;
119 		case 'u':		/* do everything in UTC */
120 			if (setenv("TZ", "UTC0", 1) != 0)
121 				err(1, "setenv: cannot set TZ=UTC0");
122 			break;
123 		case 'v':
124 			v = vary_append(v, optarg);
125 			break;
126 		default:
127 			usage();
128 		}
129 	argc -= optind;
130 	argv += optind;
131 
132 	/*
133 	 * If -d or -t, set the timezone or daylight savings time; this
134 	 * doesn't belong here; the kernel should not know about either.
135 	 */
136 	if (set_timezone && settimeofday(NULL, &tz))
137 		err(1, "settimeofday (timezone)");
138 
139 	if (!rflag && time(&tval) == -1)
140 		err(1, "time");
141 
142 	format = nl_langinfo(_DATE_FMT);
143 
144 	/* allow the operands in any order */
145 	if (*argv && **argv == '+') {
146 		format = *argv + 1;
147 		++argv;
148 	}
149 
150 	if (*argv) {
151 		setthetime(fmt, *argv, jflag, nflag);
152 		++argv;
153 	} else if (fmt != NULL)
154 		usage();
155 
156 	if (*argv && **argv == '+')
157 		format = *argv + 1;
158 
159 	lt = *localtime(&tval);
160 	badv = vary_apply(v, &lt);
161 	if (badv) {
162 		fprintf(stderr, "%s: Cannot apply date adjustment\n",
163 			badv->arg);
164 		vary_destroy(v);
165 		usage();
166 	}
167 	vary_destroy(v);
168 	strftime(buf, sizeof(buf), format, &lt);
169 	printf("%s\n", buf);
170 	if (fflush(stdout) != 0)
171 		err(1, "stdout");
172 	exit(retval);
173 }
174 
175 #define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
176 
177 static void
178 setthetime(const char *fmt, const char *p, int jflag, int nflag)
179 {
180 	struct tm *lt;
181 	struct timeval tv;
182 	const char *dot, *t;
183 	int century;
184 
185 	if (fmt != NULL) {
186 		lt = localtime(&tval);
187 		t = strptime(p, fmt, lt);
188 		if (t == NULL) {
189 			fprintf(stderr, "Failed conversion of ``%s''"
190 				" using format ``%s''\n", p, fmt);
191 			badformat();
192 		} else if (*t != '\0')
193 			fprintf(stderr, "Warning: Ignoring %ld extraneous"
194 				" characters in date string (%s)\n",
195 				(long) strlen(t), t);
196 	} else {
197 		for (t = p, dot = NULL; *t; ++t) {
198 			if (isdigit(*t))
199 				continue;
200 			if (*t == '.' && dot == NULL) {
201 				dot = t;
202 				continue;
203 			}
204 			badformat();
205 		}
206 
207 		lt = localtime(&tval);
208 
209 		if (dot != NULL) {			/* .ss */
210 			dot++; /* *dot++ = '\0'; */
211 			if (strlen(dot) != 2)
212 				badformat();
213 			lt->tm_sec = ATOI2(dot);
214 			if (lt->tm_sec > 61)
215 				badformat();
216 		} else
217 			lt->tm_sec = 0;
218 
219 		century = 0;
220 		/* if p has a ".ss" field then let's pretend it's not there */
221 		switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
222 		case 12:				/* cc */
223 			lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
224 			century = 1;
225 			/* FALLTHROUGH */
226 		case 10:				/* yy */
227 			if (century)
228 				lt->tm_year += ATOI2(p);
229 			else {				/* hack for 2000 ;-} */
230 				lt->tm_year = ATOI2(p);
231 				if (lt->tm_year < 69)
232 					lt->tm_year += 2000 - TM_YEAR_BASE;
233 				else
234 					lt->tm_year += 1900 - TM_YEAR_BASE;
235 			}
236 			/* FALLTHROUGH */
237 		case 8:					/* mm */
238 			lt->tm_mon = ATOI2(p);
239 			if (lt->tm_mon > 12)
240 				badformat();
241 			--lt->tm_mon;		/* time struct is 0 - 11 */
242 			/* FALLTHROUGH */
243 		case 6:					/* dd */
244 			lt->tm_mday = ATOI2(p);
245 			if (lt->tm_mday > 31)
246 				badformat();
247 			/* FALLTHROUGH */
248 		case 4:					/* HH */
249 			lt->tm_hour = ATOI2(p);
250 			if (lt->tm_hour > 23)
251 				badformat();
252 			/* FALLTHROUGH */
253 		case 2:					/* MM */
254 			lt->tm_min = ATOI2(p);
255 			if (lt->tm_min > 59)
256 				badformat();
257 			break;
258 		default:
259 			badformat();
260 		}
261 	}
262 
263 	/* Let mktime() decide whether summer time is in effect. */
264 	lt->tm_isdst = -1;
265 
266 	/* convert broken-down time to GMT clock time */
267 	if ((tval = mktime(lt)) == -1)
268 		errx(1, "nonexistent time");
269 
270 	if (!jflag) {
271 		/* set the time */
272 		if (nflag || netsettime(tval)) {
273 			logwtmp("|", "date", "");
274 			tv.tv_sec = tval;
275 			tv.tv_usec = 0;
276 			if (settimeofday(&tv, NULL))
277 				err(1, "settimeofday (timeval)");
278 			logwtmp("{", "date", "");
279 		}
280 
281 		if ((p = getlogin()) == NULL)
282 			p = "???";
283 		syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
284 	}
285 }
286 
287 static void
288 badformat(void)
289 {
290 	warnx("illegal time format");
291 	usage();
292 }
293 
294 static void
295 usage(void)
296 {
297 	fprintf(stderr, "%s\n%s\n",
298 	    "usage: date [-jnu] [-d dst] [-r seconds] [-t west] "
299 	    "[-v[+|-]val[ymwdHMS]] ... ",
300 	    "            "
301 	    "[-f fmt date | [[[[[cc]yy]mm]dd]HH]MM[.ss]] [+format]");
302 	exit(1);
303 }
304