date.c revision 1.34 
1/* $NetBSD: date.c,v 1.34 2001/09/13 10:06:40 wiz Exp $ */
2
3/*
4 * Copyright (c) 1985, 1987, 1988, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include <sys/cdefs.h>
37#ifndef lint
38__COPYRIGHT(
39"@(#) Copyright (c) 1985, 1987, 1988, 1993\n\
40	The Regents of the University of California.  All rights reserved.\n");
41#endif /* not lint */
42
43#ifndef lint
44#if 0
45static char sccsid[] = "@(#)date.c	8.2 (Berkeley) 4/28/95";
46#else
47__RCSID("$NetBSD: date.c,v 1.34 2001/09/13 10:06:40 wiz Exp $");
48#endif
49#endif /* not lint */
50
51#include <sys/param.h>
52#include <sys/time.h>
53
54#include <ctype.h>
55#include <err.h>
56#include <fcntl.h>
57#include <locale.h>
58#include <stdio.h>
59#include <stdlib.h>
60#include <string.h>
61#include <syslog.h>
62#include <time.h>
63#include <tzfile.h>
64#include <unistd.h>
65#include <util.h>
66
67#include "extern.h"
68
69time_t tval;
70int retval, nflag;
71
72int main(int, char *[]);
73static void badformat(void);
74static void badtime(void);
75static void setthetime(const char *);
76static void usage(void);
77
78int
79main(int argc, char *argv[])
80{
81	char buf[1024], *format;
82	int ch, rflag;
83
84	(void)setlocale(LC_ALL, "");
85
86	rflag = 0;
87	while ((ch = getopt(argc, argv, "nr:u")) != -1)
88		switch((char)ch) {
89		case 'n':		/* don't set network */
90			nflag = 1;
91			break;
92		case 'r':		/* user specified seconds */
93			rflag = 1;
94			tval = strtol(optarg, NULL, 0);
95			break;
96		case 'u':		/* do everything in UTC */
97			(void)putenv("TZ=UTC0");
98			break;
99		default:
100			usage();
101		}
102	argc -= optind;
103	argv += optind;
104
105	if (!rflag && time(&tval) == -1)
106		err(1, "time");
107
108	format = "%a %b %e %H:%M:%S %Z %Y";
109
110	/* allow the operands in any order */
111	if (*argv && **argv == '+') {
112		format = *argv + 1;
113		++argv;
114	}
115
116	if (*argv) {
117		setthetime(*argv);
118		++argv;
119	}
120
121	if (*argv && **argv == '+')
122		format = *argv + 1;
123
124	(void)strftime(buf, sizeof(buf), format, localtime(&tval));
125	(void)printf("%s\n", buf);
126	exit(retval);
127	/* NOTREACHED */
128}
129
130static void
131badformat(void)
132{
133	warnx("illegal time format");
134	usage();
135}
136
137static void
138badtime(void)
139{
140	errx(1, "illegal time");
141}
142
143#define ATOI2(s) ((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
144
145static void
146setthetime(const char *p)
147{
148	struct timeval tv;
149	struct tm *lt;
150	const char *dot, *t;
151	int len, yearset;
152
153	for (t = p, dot = NULL; *t; ++t) {
154		if (isdigit((unsigned char)*t))
155			continue;
156		if (*t == '.' && dot == NULL) {
157			dot = t;
158			continue;
159		}
160		badformat();
161	}
162
163	lt = localtime(&tval);
164
165	lt->tm_isdst = -1;			/* Divine correct DST */
166
167	if (dot != NULL) {			/* .ss */
168		len = strlen(dot);
169		if (len != 3)
170			badformat();
171		++dot;
172		lt->tm_sec = ATOI2(dot);
173	} else {
174		len = 0;
175		lt->tm_sec = 0;
176	}
177
178	yearset = 0;
179	switch (strlen(p) - len) {
180	case 12:				/* cc */
181		lt->tm_year = ATOI2(p) * 100 - TM_YEAR_BASE;
182		yearset = 1;
183		/* FALLTHROUGH */
184	case 10:				/* yy */
185		if (yearset) {
186			lt->tm_year += ATOI2(p);
187		} else {
188			yearset = ATOI2(p);
189			if (yearset < 69)
190				lt->tm_year = yearset + 2000 - TM_YEAR_BASE;
191			else
192				lt->tm_year = yearset + 1900 - TM_YEAR_BASE;
193		}
194		/* FALLTHROUGH */
195	case 8:					/* mm */
196		lt->tm_mon = ATOI2(p);
197		--lt->tm_mon;			/* time struct is 0 - 11 */
198		/* FALLTHROUGH */
199	case 6:					/* dd */
200		lt->tm_mday = ATOI2(p);
201		/* FALLTHROUGH */
202	case 4:					/* hh */
203		lt->tm_hour = ATOI2(p);
204		/* FALLTHROUGH */
205	case 2:					/* mm */
206		lt->tm_min = ATOI2(p);
207		break;
208	default:
209		badformat();
210	}
211
212	/* convert broken-down time to UTC clock time */
213	if ((tval = mktime(lt)) == -1)
214		badtime();
215
216	/* set the time */
217	if (nflag || netsettime(tval)) {
218		logwtmp("|", "date", "");
219		tv.tv_sec = tval;
220		tv.tv_usec = 0;
221		if (settimeofday(&tv, NULL)) {
222			perror("date: settimeofday");
223			exit(1);
224		}
225		logwtmp("{", "date", "");
226	}
227
228	if ((p = getlogin()) == NULL)
229		p = "???";
230	syslog(LOG_AUTH | LOG_NOTICE, "date set by %s", p);
231}
232
233static void
234usage(void)
235{
236	(void)fprintf(stderr,
237	    "usage: %s [-nu] [-r seconds] [+format]\n", getprogname());
238	(void)fprintf(stderr, "       %s [[[[[cc]yy]mm]dd]hh]mm[.ss]\n", getprogname());
239	exit(1);
240	/* NOTREACHED */
241}
242