xref: /openbsd-src/usr.bin/leave/leave.c (revision f2da64fbbbf1b03f09f390ab01267c93dfd77c4c)
1 /*	$OpenBSD: leave.c,v 1.17 2015/10/09 01:37:08 deraadt Exp $	*/
2 /*	$NetBSD: leave.c,v 1.4 1995/07/03 16:50:13 phil Exp $	*/
3 
4 /*
5  * Copyright (c) 1980, 1988, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/time.h>
34 #include <ctype.h>
35 #include <err.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <unistd.h>
39 
40 static __dead void	usage(void);
41 static void		doalarm(u_int secs);
42 
43 #define SECOND  1
44 #define MINUTE  (SECOND * 60)
45 #define	FIVEMIN	(5 * MINUTE)
46 #define HOUR    (MINUTE * 60)
47 
48 /*
49  * leave [[+]hhmm]
50  *
51  * Reminds you when you have to leave.
52  * Leave prompts for input and goes away if you hit return.
53  * It nags you like a mother hen.
54  */
55 int
56 main(int argc, char *argv[])
57 {
58 	u_int secs;
59 	int hours, minutes;
60 	char c, *cp;
61 	struct tm *t;
62 	time_t now;
63 	int plusnow = 0, twentyfour;
64 	char buf[50];
65 
66 	if (pledge("stdio proc", NULL) == -1)
67 		err(1, "pledge");
68 
69 	if (setvbuf(stdout, NULL, _IOLBF, 0) != 0)
70 		errx(1, "Cannot set stdout to line buffered.");
71 
72 	if (argc < 2) {
73 		(void)fputs("When do you have to leave? ", stdout);
74 		cp = fgets(buf, sizeof(buf), stdin);
75 		if (cp == NULL || *cp == '\n')
76 			exit(0);
77 	} else if (argc > 2)
78 		usage();
79 	else
80 		cp = argv[1];
81 
82 	if (*cp == '+') {
83 		plusnow = 1;
84 		++cp;
85 	}
86 
87 	for (hours = 0; (c = *cp) && c != '\n'; ++cp) {
88 		if (!isdigit((unsigned char)c))
89 			usage();
90 		hours = hours * 10 + (c - '0');
91 	}
92 	minutes = hours % 100;
93 	hours /= 100;
94 	/* determine 24 hours mode */
95 	twentyfour = hours > 12;
96 
97 	if (minutes < 0 || minutes > 59)
98 		usage();
99 	if (plusnow)
100 		secs = (hours * HOUR) + (minutes * MINUTE);
101 	else {
102 		if (hours > 23)
103 			usage();
104 		(void)time(&now);
105 		t = localtime(&now);
106 		while (t->tm_hour > hours ||
107 		    (t->tm_hour == hours && t->tm_min >= minutes)) {
108 			if (twentyfour)
109 				hours += 24;
110 			else
111 				hours += 12;
112 		}
113 
114 		secs = (hours - t->tm_hour) * HOUR;
115 		secs += (minutes - t->tm_min) * MINUTE;
116 	}
117 	doalarm(secs);
118 	exit(0);
119 }
120 
121 static void
122 doalarm(u_int secs)
123 {
124 	int bother;
125 	time_t daytime;
126 	pid_t pid;
127 
128 	switch (pid = fork()) {
129 	case 0:
130 		break;
131 	case -1:
132 		err(1, "Fork failed");
133 		/* NOTREACHED */
134 	default:
135 		(void)time(&daytime);
136 		daytime += secs;
137 		printf("Alarm set for %.16s. (pid %ld)\n",
138 		    ctime(&daytime), (long)pid);
139 		exit(0);
140 	}
141 	sleep(2);			/* let parent print set message */
142 
143 	/*
144 	 * if write fails, we've lost the terminal through someone else
145 	 * causing a vhangup by logging in.
146 	 */
147 	if (secs >= FIVEMIN) {
148 		sleep(secs - FIVEMIN);
149 		if (puts("\a\aYou have to leave in 5 minutes.") == EOF)
150 			exit(0);
151 		secs = FIVEMIN;
152 	}
153 
154 	if (secs >= MINUTE) {
155 		sleep(secs - MINUTE);
156 		if (puts("\a\aJust one more minute!") == EOF)
157 			exit(0);
158 	}
159 
160 	for (bother = 10; bother--;) {
161 		sleep(MINUTE);
162 		if (puts("\a\aTime to leave!") == EOF)
163 			exit(0);
164 	}
165 
166 	puts("\a\aThat was the last time I'll tell you.  Bye.");
167 	exit(0);
168 }
169 
170 static __dead void
171 usage(void)
172 {
173 	fprintf(stderr, "usage: leave [[+]hhmm]\n");
174 	exit(1);
175 }
176