xref: /dragonfly/bin/date/date.c (revision 1bf4b486)
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 1.13 2005/07/20 19:51:56 cpressey 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 			setenv("TZ", "UTC0", 1);
121 			break;
122 		case 'v':
123 			v = vary_append(v, optarg);
124 			break;
125 		default:
126 			usage();
127 		}
128 	argc -= optind;
129 	argv += optind;
130 
131 	/*
132 	 * If -d or -t, set the timezone or daylight savings time; this
133 	 * doesn't belong here; the kernel should not know about either.
134 	 */
135 	if (set_timezone && settimeofday((struct timeval *)NULL, &tz))
136 		err(1, "settimeofday (timezone)");
137 
138 	if (!rflag && time(&tval) == -1)
139 		err(1, "time");
140 
141 	format = nl_langinfo(_DATE_FMT);
142 
143 	/* allow the operands in any order */
144 	if (*argv && **argv == '+') {
145 		format = *argv + 1;
146 		++argv;
147 	}
148 
149 	if (*argv) {
150 		setthetime(fmt, *argv, jflag, nflag);
151 		++argv;
152 	} else if (fmt != NULL)
153 		usage();
154 
155 	if (*argv && **argv == '+')
156 		format = *argv + 1;
157 
158 	lt = *localtime(&tval);
159 	badv = vary_apply(v, &lt);
160 	if (badv) {
161 		fprintf(stderr, "%s: Cannot apply date adjustment\n",
162 			badv->arg);
163 		vary_destroy(v);
164 		usage();
165 	}
166 	vary_destroy(v);
167 	strftime(buf, sizeof(buf), format, &lt);
168 	printf("%s\n", buf);
169 	if (fflush(stdout) != 0)
170 		err(1, "stdout");
171 	exit(retval);
172 }
173 
174 #define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
175 
176 static void
177 setthetime(const char *fmt, const char *p, int jflag, int nflag)
178 {
179 	struct tm *lt;
180 	struct timeval tv;
181 	const char *dot, *t;
182 	int century;
183 
184 	if (fmt != NULL) {
185 		lt = localtime(&tval);
186 		t = strptime(p, fmt, lt);
187 		if (t == NULL) {
188 			fprintf(stderr, "Failed conversion of ``%s''"
189 				" using format ``%s''\n", p, fmt);
190 			badformat();
191 		} else if (*t != '\0')
192 			fprintf(stderr, "Warning: Ignoring %ld extraneous"
193 				" characters in date string (%s)\n",
194 				(long) strlen(t), t);
195 	} else {
196 		for (t = p, dot = NULL; *t; ++t) {
197 			if (isdigit(*t))
198 				continue;
199 			if (*t == '.' && dot == NULL) {
200 				dot = t;
201 				continue;
202 			}
203 			badformat();
204 		}
205 
206 		lt = localtime(&tval);
207 
208 		if (dot != NULL) {			/* .ss */
209 			dot++; /* *dot++ = '\0'; */
210 			if (strlen(dot) != 2)
211 				badformat();
212 			lt->tm_sec = ATOI2(dot);
213 			if (lt->tm_sec > 61)
214 				badformat();
215 		} else
216 			lt->tm_sec = 0;
217 
218 		century = 0;
219 		/* if p has a ".ss" field then let's pretend it's not there */
220 		switch (strlen(p) - ((dot != NULL) ? 3 : 0)) {
221 		case 12:				/* cc */
222 			lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
223 			century = 1;
224 			/* FALLTHROUGH */
225 		case 10:				/* yy */
226 			if (century)
227 				lt->tm_year += ATOI2(p);
228 			else {				/* hack for 2000 ;-} */
229 				lt->tm_year = ATOI2(p);
230 				if (lt->tm_year < 69)
231 					lt->tm_year += 2000 - TM_YEAR_BASE;
232 				else
233 					lt->tm_year += 1900 - TM_YEAR_BASE;
234 			}
235 			/* FALLTHROUGH */
236 		case 8:					/* mm */
237 			lt->tm_mon = ATOI2(p);
238 			if (lt->tm_mon > 12)
239 				badformat();
240 			--lt->tm_mon;		/* time struct is 0 - 11 */
241 			/* FALLTHROUGH */
242 		case 6:					/* dd */
243 			lt->tm_mday = ATOI2(p);
244 			if (lt->tm_mday > 31)
245 				badformat();
246 			/* FALLTHROUGH */
247 		case 4:					/* HH */
248 			lt->tm_hour = ATOI2(p);
249 			if (lt->tm_hour > 23)
250 				badformat();
251 			/* FALLTHROUGH */
252 		case 2:					/* MM */
253 			lt->tm_min = ATOI2(p);
254 			if (lt->tm_min > 59)
255 				badformat();
256 			break;
257 		default:
258 			badformat();
259 		}
260 	}
261 
262 	/* Let mktime() decide whether summer time is in effect. */
263 	lt->tm_isdst = -1;
264 
265 	/* convert broken-down time to GMT clock time */
266 	if ((tval = mktime(lt)) == -1)
267 		errx(1, "nonexistent time");
268 
269 	if (!jflag) {
270 		/* set the time */
271 		if (nflag || netsettime(tval)) {
272 			logwtmp("|", "date", "");
273 			tv.tv_sec = tval;
274 			tv.tv_usec = 0;
275 			if (settimeofday(&tv, (struct timezone *)NULL))
276 				err(1, "settimeofday (timeval)");
277 			logwtmp("{", "date", "");
278 		}
279 
280 		if ((p = getlogin()) == NULL)
281 			p = "???";
282 		syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
283 	}
284 }
285 
286 static void
287 badformat(void)
288 {
289 	warnx("illegal time format");
290 	usage();
291 }
292 
293 static void
294 usage(void)
295 {
296 	fprintf(stderr, "%s\n%s\n",
297 	    "usage: date [-jnu] [-d dst] [-r seconds] [-t west] "
298 	    "[-v[+|-]val[ymwdHMS]] ... ",
299 	    "            "
300 	    "[-f fmt date | [[[[[cc]yy]mm]dd]HH]MM[.ss]] [+format]");
301 	exit(1);
302 }
303