xref: /freebsd/usr.bin/calendar/calendar.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1 /*-
2  * Copyright (c) 1989, 1993, 1994
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 const char copyright[] =
32 "@(#) Copyright (c) 1989, 1993\n\
33 	The Regents of the University of California.  All rights reserved.\n";
34 #endif
35 
36 #if 0
37 #ifndef lint
38 static char sccsid[] = "@(#)calendar.c	8.3 (Berkeley) 3/25/94";
39 #endif
40 #endif
41 
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44 
45 #include <err.h>
46 #include <errno.h>
47 #include <locale.h>
48 #include <pwd.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <time.h>
53 #include <unistd.h>
54 
55 #include "calendar.h"
56 
57 #define	UTCOFFSET_NOTSET	100	/* Expected between -24 and +24 */
58 #define	LONGITUDE_NOTSET	1000	/* Expected between -360 and +360 */
59 
60 struct passwd	*pw;
61 int		doall = 0;
62 int		debug = 0;
63 static char	*DEBUG = NULL;
64 static time_t	f_time = 0;
65 double		UTCOffset = UTCOFFSET_NOTSET;
66 int		EastLongitude = LONGITUDE_NOTSET;
67 
68 static void	usage(void) __dead2;
69 
70 int
71 main(int argc, char *argv[])
72 {
73 	int	f_dayAfter = 0;		/* days after current date */
74 	int	f_dayBefore = 0;	/* days before current date */
75 	int	Friday = 5;		/* day before weekend */
76 
77 	int ch;
78 	struct tm tp1, tp2;
79 
80 	(void)setlocale(LC_ALL, "");
81 
82 	while ((ch = getopt(argc, argv, "-A:aB:D:dF:f:l:t:U:W:?")) != -1)
83 		switch (ch) {
84 		case '-':		/* backward contemptible */
85 		case 'a':
86 			if (getuid()) {
87 				errno = EPERM;
88 				err(1, NULL);
89 			}
90 			doall = 1;
91 			break;
92 
93 		case 'W': /* we don't need no steenking Fridays */
94 			Friday = -1;
95 			/* FALLTHROUGH */
96 
97 		case 'A': /* days after current date */
98 			f_dayAfter = atoi(optarg);
99 			if (f_dayAfter < 0)
100 				errx(1, "number of days must be positive");
101 			break;
102 
103 		case 'B': /* days before current date */
104 			f_dayBefore = atoi(optarg);
105 			if (f_dayBefore < 0)
106 				errx(1, "number of days must be positive");
107 			break;
108 
109 		case 'D': /* debug output of sun and moon info */
110 			DEBUG = optarg;
111 			break;
112 
113 		case 'd': /* debug output of current date */
114 			debug = 1;
115 			break;
116 
117 		case 'F': /* Change the time: When does weekend start? */
118 			Friday = atoi(optarg);
119 			break;
120 
121 		case 'f': /* other calendar file */
122 			calendarFile = optarg;
123 			break;
124 
125 		case 'l': /* Change longitudal position */
126 			EastLongitude = strtol(optarg, NULL, 10);
127 			break;
128 
129 		case 't': /* other date, for tests */
130 			f_time = Mktime(optarg);
131 			break;
132 
133 		case 'U': /* Change UTC offset */
134 			UTCOffset = strtod(optarg, NULL);
135 			break;
136 
137 		case '?':
138 		default:
139 			usage();
140 		}
141 
142 	argc -= optind;
143 	argv += optind;
144 
145 	if (argc)
146 		usage();
147 
148 	/* use current time */
149 	if (f_time <= 0)
150 		(void)time(&f_time);
151 
152 	/* if not set, determine where I could be */
153 	{
154 		if (UTCOffset == UTCOFFSET_NOTSET &&
155 		    EastLongitude == LONGITUDE_NOTSET) {
156 			/* Calculate on difference between here and UTC */
157 			time_t t;
158 			struct tm tm;
159 			long utcoffset, hh, mm, ss;
160 			double uo;
161 
162 			time(&t);
163 			localtime_r(&t, &tm);
164 			utcoffset = tm.tm_gmtoff;
165 			/* seconds -> hh:mm:ss */
166 			hh = utcoffset / SECSPERHOUR;
167 			utcoffset %= SECSPERHOUR;
168 			mm = utcoffset / SECSPERMINUTE;
169 			utcoffset %= SECSPERMINUTE;
170 			ss = utcoffset;
171 
172 			/* hh:mm:ss -> hh.mmss */
173 			uo = mm + (100.0 * (ss / 60.0));
174 			uo /=  60.0 / 100.0;
175 			uo = hh + uo / 100;
176 
177 			UTCOffset = uo;
178 			EastLongitude = UTCOffset * 15;
179 		} else if (UTCOffset == UTCOFFSET_NOTSET) {
180 			/* Base on information given */
181 			UTCOffset = EastLongitude / 15;
182 		} else if (EastLongitude == LONGITUDE_NOTSET) {
183 			/* Base on information given */
184 			EastLongitude = UTCOffset * 15;
185 		}
186 	}
187 
188 	settimes(f_time, f_dayBefore, f_dayAfter, Friday, &tp1, &tp2);
189 	generatedates(&tp1, &tp2);
190 
191 	/*
192 	 * FROM now on, we are working in UTC.
193 	 * This will only affect moon and sun related events anyway.
194 	 */
195 	if (setenv("TZ", "UTC", 1) != 0)
196 		errx(1, "setenv: %s", strerror(errno));
197 	tzset();
198 
199 	if (debug)
200 		dumpdates();
201 
202 	if (DEBUG != NULL) {
203 		dodebug(DEBUG);
204 		exit(0);
205 	}
206 
207 	if (doall)
208 		while ((pw = getpwent()) != NULL) {
209 			(void)setegid(pw->pw_gid);
210 			(void)initgroups(pw->pw_name, pw->pw_gid);
211 			(void)seteuid(pw->pw_uid);
212 			if (!chdir(pw->pw_dir))
213 				cal();
214 			(void)seteuid(0);
215 		}
216 	else
217 		cal();
218 	exit(0);
219 }
220 
221 
222 static void __dead2
223 usage(void)
224 {
225 
226 	fprintf(stderr, "%s\n%s\n%s\n",
227 	    "usage: calendar [-A days] [-a] [-B days] [-D sun|moon] [-d]",
228 	    "		     [-F friday] [-f calendarfile] [-l longitude]",
229 	    "		     [-t dd[.mm[.year]]] [-U utcoffset] [-W days]"
230 	    );
231 	exit(1);
232 }
233