xref: /freebsd/usr.bin/calendar/calendar.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993, 1994
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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/types.h>
33 #include <err.h>
34 #include <errno.h>
35 #include <locale.h>
36 #include <login_cap.h>
37 #include <langinfo.h>
38 #include <pwd.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <time.h>
43 #include <unistd.h>
44 
45 #include "calendar.h"
46 
47 #define	UTCOFFSET_NOTSET	100	/* Expected between -24 and +24 */
48 #define	LONGITUDE_NOTSET	1000	/* Expected between -360 and +360 */
49 
50 struct passwd	*pw;
51 int		doall = 0;
52 int		debug = 0;
53 static char	*DEBUG = NULL;
54 static time_t	f_time = 0;
55 double		UTCOffset = UTCOFFSET_NOTSET;
56 int		EastLongitude = LONGITUDE_NOTSET;
57 #ifdef WITH_ICONV
58 const char	*outputEncoding = NULL;
59 #endif
60 
61 static void	usage(void) __dead2;
62 
63 int
64 main(int argc, char *argv[])
65 {
66 	int	f_dayAfter = 0;		/* days after current date */
67 	int	f_dayBefore = 0;	/* days before current date */
68 	int	Friday = 5;		/* day before weekend */
69 
70 	int ch;
71 	struct tm tp1, tp2;
72 
73 	(void)setlocale(LC_ALL, "");
74 
75 	while ((ch = getopt(argc, argv, "-A:aB:D:dF:f:l:t:U:W:?")) != -1)
76 		switch (ch) {
77 		case '-':		/* backward contemptible */
78 		case 'a':
79 			if (getuid()) {
80 				errno = EPERM;
81 				err(1, NULL);
82 			}
83 			doall = 1;
84 			break;
85 
86 		case 'W': /* we don't need no steenking Fridays */
87 			Friday = -1;
88 			/* FALLTHROUGH */
89 
90 		case 'A': /* days after current date */
91 			f_dayAfter = atoi(optarg);
92 			if (f_dayAfter < 0)
93 				errx(1, "number of days must be positive");
94 			break;
95 
96 		case 'B': /* days before current date */
97 			f_dayBefore = atoi(optarg);
98 			if (f_dayBefore < 0)
99 				errx(1, "number of days must be positive");
100 			break;
101 
102 		case 'D': /* debug output of sun and moon info */
103 			DEBUG = optarg;
104 			break;
105 
106 		case 'd': /* debug output of current date */
107 			debug = 1;
108 			break;
109 
110 		case 'F': /* Change the time: When does weekend start? */
111 			Friday = atoi(optarg);
112 			break;
113 
114 		case 'f': /* other calendar file */
115 			calendarFile = optarg;
116 			break;
117 
118 		case 'l': /* Change longitudal position */
119 			EastLongitude = strtol(optarg, NULL, 10);
120 			break;
121 
122 		case 't': /* other date, for tests */
123 			f_time = Mktime(optarg);
124 			break;
125 
126 		case 'U': /* Change UTC offset */
127 			UTCOffset = strtod(optarg, NULL);
128 			break;
129 
130 		case '?':
131 		default:
132 			usage();
133 		}
134 
135 	argc -= optind;
136 	argv += optind;
137 
138 	if (argc)
139 		usage();
140 
141 	/* use current time */
142 	if (f_time <= 0)
143 		(void)time(&f_time);
144 
145 	/* if not set, determine where I could be */
146 	{
147 		if (UTCOffset == UTCOFFSET_NOTSET &&
148 		    EastLongitude == LONGITUDE_NOTSET) {
149 			/* Calculate on difference between here and UTC */
150 			time_t t;
151 			struct tm tm;
152 			long utcoffset, hh, mm, ss;
153 			double uo;
154 
155 			time(&t);
156 			localtime_r(&t, &tm);
157 			utcoffset = tm.tm_gmtoff;
158 			/* seconds -> hh:mm:ss */
159 			hh = utcoffset / SECSPERHOUR;
160 			utcoffset %= SECSPERHOUR;
161 			mm = utcoffset / SECSPERMINUTE;
162 			utcoffset %= SECSPERMINUTE;
163 			ss = utcoffset;
164 
165 			/* hh:mm:ss -> hh.mmss */
166 			uo = mm + (100.0 * (ss / 60.0));
167 			uo /=  60.0 / 100.0;
168 			uo = hh + uo / 100;
169 
170 			UTCOffset = uo;
171 			EastLongitude = UTCOffset * 15;
172 		} else if (UTCOffset == UTCOFFSET_NOTSET) {
173 			/* Base on information given */
174 			UTCOffset = EastLongitude / 15;
175 		} else if (EastLongitude == LONGITUDE_NOTSET) {
176 			/* Base on information given */
177 			EastLongitude = UTCOffset * 15;
178 		}
179 	}
180 
181 	settimes(f_time, f_dayBefore, f_dayAfter, Friday, &tp1, &tp2);
182 	generatedates(&tp1, &tp2);
183 
184 	/*
185 	 * FROM now on, we are working in UTC.
186 	 * This will only affect moon and sun related events anyway.
187 	 */
188 	if (setenv("TZ", "UTC", 1) != 0)
189 		errx(1, "setenv: %s", strerror(errno));
190 	tzset();
191 
192 	if (debug)
193 		dumpdates();
194 
195 	if (DEBUG != NULL) {
196 		dodebug(DEBUG);
197 		exit(0);
198 	}
199 
200 	if (doall)
201 		while ((pw = getpwent()) != NULL) {
202 			pid_t pid;
203 
204 			if (chdir(pw->pw_dir) == -1)
205 				continue;
206 			pid = fork();
207 			if (pid < 0)
208 				err(1, "fork");
209 			if (pid == 0) {
210 				login_cap_t *lc;
211 
212 				lc = login_getpwclass(pw);
213 				if (setusercontext(lc, pw, pw->pw_uid,
214 				    LOGIN_SETALL) != 0)
215 					errx(1, "setusercontext");
216 				setenv("HOME", pw->pw_dir, 1);
217 				cal();
218 				exit(0);
219 			}
220 		}
221 	else {
222 #ifdef WITH_ICONV
223 		/* Save the information about the encoding used in the terminal. */
224 		outputEncoding = strdup(nl_langinfo(CODESET));
225 		if (outputEncoding == NULL)
226 			errx(1, "cannot allocate memory");
227 #endif
228 		cal();
229 	}
230 	exit(0);
231 }
232 
233 
234 static void __dead2
235 usage(void)
236 {
237 
238 	fprintf(stderr, "%s\n%s\n%s\n",
239 	    "usage: calendar [-A days] [-a] [-B days] [-D sun|moon] [-d]",
240 	    "		     [-F friday] [-f calendarfile] [-l longitude]",
241 	    "		     [-t dd[.mm[.year]]] [-U utcoffset] [-W days]"
242 	    );
243 	exit(1);
244 }
245