xref: /illumos-gate/usr/src/cmd/date/date.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 /*
43  *	date - with format capabilities and international flair
44  */
45 
46 #include	<locale.h>
47 #include	<fcntl.h>
48 #include	<langinfo.h>
49 #include	<stdio.h>
50 #include	<stdlib.h>
51 #include	<string.h>
52 #include	<time.h>
53 #include	<unistd.h>
54 #include	<sys/time.h>
55 #include	<sys/types.h>
56 #include	<ctype.h>
57 #include	<utmpx.h>
58 #include	<tzfile.h>
59 
60 #define	year_size(A)	((isleap(A)) ? 366 : 365)
61 static 	char	buf[BUFSIZ];
62 static	time_t	clock_val;
63 static  short	month_size[12] =
64 	{ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
65 static  struct  utmpx wtmpx[2] = {
66 	{"", "", OTIME_MSG, 0, OLD_TIME, 0, 0, 0},
67 	{"", "", NTIME_MSG, 0, NEW_TIME, 0, 0, 0}
68 	};
69 static char *usage =
70 	"usage:\tdate [-u] mmddHHMM[[cc]yy][.SS]\n\tdate [-u] [+format]\n"
71 	"\tdate -a [-]sss[.fff]\n";
72 static int uflag = 0;
73 
74 static int get_adj(char *, struct timeval *);
75 static int setdate(struct tm *, char *);
76 
77 int
78 main(int argc, char **argv)
79 {
80 	struct tm *tp, tm;
81 	struct timeval tv;
82 	char *fmt;
83 	int c, aflag = 0, illflag = 0;
84 
85 	(void) setlocale(LC_ALL, "");
86 
87 #if !defined(TEXT_DOMAIN)
88 #define	TEXT_DOMAIN "SYS_TEST"
89 #endif
90 	(void) textdomain(TEXT_DOMAIN);
91 
92 	while ((c = getopt(argc, argv, "a:u")) != EOF)
93 		switch (c) {
94 		case 'a':
95 			aflag++;
96 			if (get_adj(optarg, &tv) < 0) {
97 				(void) fprintf(stderr,
98 				    gettext("date: invalid argument -- %s\n"),
99 						optarg);
100 				illflag++;
101 			}
102 			break;
103 		case 'u':
104 			uflag++;
105 			break;
106 		default:
107 			illflag++;
108 		}
109 
110 	argc -= optind;
111 	argv  = &argv[optind];
112 
113 	/* -u and -a are mutually exclusive */
114 	if (uflag && aflag)
115 		illflag++;
116 
117 	if (illflag) {
118 		(void) fprintf(stderr, gettext(usage));
119 		exit(1);
120 	}
121 
122 	(void) time(&clock_val);
123 
124 	if (aflag) {
125 		if (adjtime(&tv, 0) < 0) {
126 			perror(gettext("date: Failed to adjust date"));
127 			exit(1);
128 		}
129 		exit(0);
130 	}
131 
132 	if (argc > 0) {
133 		if (*argv[0] == '+')
134 			fmt = &argv[0][1];
135 		else {
136 			if (setdate(localtime(&clock_val), argv[0])) {
137 				(void) fprintf(stderr, gettext(usage));
138 				exit(1);
139 			}
140 			fmt = nl_langinfo(_DATE_FMT);
141 		}
142 	} else
143 		fmt = nl_langinfo(_DATE_FMT);
144 
145 	if (uflag) {
146 		(void) putenv("TZ=GMT0");
147 		tzset();
148 		tp = gmtime(&clock_val);
149 	} else
150 		tp = localtime(&clock_val);
151 	(void) memcpy(&tm, tp, sizeof (struct tm));
152 	(void) strftime(buf, BUFSIZ, fmt, &tm);
153 
154 	(void) puts(buf);
155 
156 	return (0);
157 }
158 
159 int
160 setdate(struct tm *current_date, char *date)
161 {
162 	int	i;
163 	int	mm;
164 	int	hh;
165 	int	min;
166 	int	sec = 0;
167 	char	*secptr;
168 	int	yy;
169 	int	dd	= 0;
170 	int	minidx	= 6;
171 	int	len;
172 	int	dd_check;
173 
174 	/*  Parse date string  */
175 	if ((secptr = strchr(date, '.')) != NULL && strlen(&secptr[1]) == 2 &&
176 	    isdigit(secptr[1]) && isdigit(secptr[2]) &&
177 	    (sec = atoi(&secptr[1])) >= 0 && sec < 60)
178 		secptr[0] = '\0';	/* eat decimal point only on success */
179 
180 	len = strlen(date);
181 
182 	for (i = 0; i < len; i++) {
183 		if (!isdigit(date[i])) {
184 			(void) fprintf(stderr,
185 			gettext("date: bad conversion\n"));
186 			exit(1);
187 		}
188 	}
189 	switch (strlen(date)) {
190 	case 12:
191 		yy = atoi(&date[8]);
192 		date[8] = '\0';
193 		break;
194 	case 10:
195 		/*
196 		 * The YY format has the following representation:
197 		 * 00-68 = 2000 thru 2068
198 		 * 69-99 = 1969 thru 1999
199 		 */
200 		if (atoi(&date[8]) <= 68) {
201 			yy = 1900 + (atoi(&date[8]) + 100);
202 		} else {
203 			yy = 1900 + atoi(&date[8]);
204 		}
205 		date[8] = '\0';
206 		break;
207 	case 8:
208 		yy = 1900 + current_date->tm_year;
209 		break;
210 	case 4:
211 		yy = 1900 + current_date->tm_year;
212 		mm = current_date->tm_mon + 1; 	/* tm_mon goes from 1 to 11 */
213 		dd = current_date->tm_mday;
214 		minidx = 2;
215 		break;
216 	default:
217 		(void) fprintf(stderr, gettext("date: bad conversion\n"));
218 		return (1);
219 	}
220 
221 	min = atoi(&date[minidx]);
222 	date[minidx] = '\0';
223 	hh = atoi(&date[minidx-2]);
224 	date[minidx-2] = '\0';
225 
226 	if (!dd) {
227 		/*
228 		 * if dd is 0 (not between 1 and 31), then
229 		 * read the value supplied by the user.
230 		 */
231 		dd = atoi(&date[2]);
232 		date[2] = '\0';
233 		mm = atoi(&date[0]);
234 	}
235 
236 	if (hh == 24)
237 		hh = 0, dd++;
238 
239 	/*  Validate date elements  */
240 	dd_check = 0;
241 	if (mm >= 1 && mm <= 12) {
242 		dd_check = month_size[mm - 1];	/* get days in this month */
243 		if (mm == 2 && isleap(yy))	/* adjust for leap year */
244 			dd_check++;
245 	}
246 	if (!((mm >= 1 && mm <= 12) && (dd >= 1 && dd <= dd_check) &&
247 		(hh >= 0 && hh <= 23) && (min >= 0 && min <= 59))) {
248 		(void) fprintf(stderr, gettext("date: bad conversion\n"));
249 		return (1);
250 	}
251 
252 	/*  Build date and time number  */
253 	for (clock_val = 0, i = 1970; i < yy; i++)
254 		clock_val += year_size(i);
255 	/*  Adjust for leap year  */
256 	if (isleap(yy) && mm >= 3)
257 		clock_val += 1;
258 	/*  Adjust for different month lengths  */
259 	while (--mm)
260 		clock_val += (time_t)month_size[mm - 1];
261 	/*  Load up the rest  */
262 	clock_val += (time_t)(dd - 1);
263 	clock_val *= 24;
264 	clock_val += (time_t)hh;
265 	clock_val *= 60;
266 	clock_val += (time_t)min;
267 	clock_val *= 60;
268 	clock_val += sec;
269 
270 	if (!uflag) {
271 		/* convert to GMT assuming standard time */
272 		/* correction is made in localtime(3C) */
273 
274 		/*
275 		 * call localtime to set up "timezone" variable applicable
276 		 * for clock_val time, to support Olson timezones which
277 		 * can allow timezone rules to change.
278 		 */
279 		(void) localtime(&clock_val);
280 
281 		clock_val += (time_t)timezone;
282 
283 		/* correct if daylight savings time in effect */
284 
285 		if (localtime(&clock_val)->tm_isdst)
286 			clock_val = clock_val - (time_t)(timezone - altzone);
287 	}
288 
289 	(void) time(&wtmpx[0].ut_xtime);
290 	if (stime(&clock_val) < 0) {
291 		perror("date");
292 		return (1);
293 	}
294 #if defined(i386)
295 	/* correct the kernel's "gmt_lag" and the PC's RTC */
296 	(void) system("/usr/sbin/rtc -c > /dev/null 2>&1");
297 #endif
298 	(void) time(&wtmpx[1].ut_xtime);
299 	(void) pututxline(&wtmpx[0]);
300 	(void) pututxline(&wtmpx[1]);
301 	(void) updwtmpx(WTMPX_FILE, &wtmpx[0]);
302 	(void) updwtmpx(WTMPX_FILE, &wtmpx[1]);
303 	return (0);
304 }
305 
306 int
307 get_adj(char *cp, struct timeval *tp)
308 {
309 	register int mult;
310 	int sign;
311 
312 	/* arg must be [-]sss[.fff] */
313 
314 	tp->tv_sec = tp->tv_usec = 0;
315 	if (*cp == '-') {
316 		sign = -1;
317 		cp++;
318 	} else {
319 		sign = 1;
320 	}
321 
322 	while (*cp >= '0' && *cp <= '9') {
323 		tp->tv_sec *= 10;
324 		tp->tv_sec += *cp++ - '0';
325 	}
326 	if (*cp == '.') {
327 		cp++;
328 		mult = 100000;
329 		while (*cp >= '0' && *cp <= '9') {
330 			tp->tv_usec += (*cp++ - '0') * mult;
331 			mult /= 10;
332 		}
333 	}
334 	/*
335 	 * if there's anything left in the string,
336 	 * the input was invalid.
337 	 */
338 	if (*cp) {
339 		return (-1);
340 	} else {
341 		tp->tv_sec *= sign;
342 		tp->tv_usec *= sign;
343 		return (0);
344 	}
345 }
346