1 /* $OpenBSD: sleep.c,v 1.29 2020/02/25 15:46:15 cheloha Exp $ */
2 /* $NetBSD: sleep.c,v 1.8 1995/03/21 09:11:11 cgd Exp $ */
3
4 /*
5 * Copyright (c) 1988, 1993, 1994
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
35 #include <ctype.h>
36 #include <err.h>
37 #include <signal.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <time.h>
41 #include <unistd.h>
42
43 void alarmh(int);
44 void usage(void);
45
46 int
main(int argc,char * argv[])47 main(int argc, char *argv[])
48 {
49 struct timespec rqtp;
50 time_t t;
51 char *cp;
52 int ch, i;
53
54 if (pledge("stdio", NULL) == -1)
55 err(1, "pledge");
56
57 signal(SIGALRM, alarmh);
58
59 while ((ch = getopt(argc, argv, "")) != -1) {
60 switch(ch) {
61 default:
62 usage();
63 }
64 }
65 argc -= optind;
66 argv += optind;
67
68 if (argc != 1)
69 usage();
70
71 timespecclear(&rqtp);
72
73 /* Handle whole seconds. */
74 for (cp = argv[0]; *cp != '\0' && *cp != '.'; cp++) {
75 if (!isdigit((unsigned char)*cp))
76 errx(1, "seconds is invalid: %s", argv[0]);
77 t = (rqtp.tv_sec * 10) + (*cp - '0');
78 if (t / 10 != rqtp.tv_sec) /* overflow */
79 errx(1, "seconds is too large: %s", argv[0]);
80 rqtp.tv_sec = t;
81 }
82
83 /*
84 * Handle fractions of a second. The multiplier divides to zero
85 * after nine digits so anything more precise than a nanosecond is
86 * validated but not used.
87 */
88 if (*cp == '.') {
89 i = 100000000;
90 for (cp++; *cp != '\0'; cp++) {
91 if (!isdigit((unsigned char)*cp))
92 errx(1, "seconds is invalid: %s", argv[0]);
93 rqtp.tv_nsec += (*cp - '0') * i;
94 i /= 10;
95 }
96 }
97
98 if (timespecisset(&rqtp)) {
99 if (nanosleep(&rqtp, NULL) == -1)
100 err(1, "nanosleep");
101 }
102
103 return 0;
104 }
105
106 void
usage(void)107 usage(void)
108 {
109 fprintf(stderr, "usage: %s seconds\n", getprogname());
110 exit(1);
111 }
112
113 /*
114 * POSIX.1 says sleep(1) may exit with status zero upon receipt
115 * of SIGALRM.
116 */
117 void
alarmh(int signo)118 alarmh(int signo)
119 {
120 /*
121 * Always _exit(2) from signal handlers: exit(3) is not
122 * generally signal-safe.
123 */
124 _exit(0);
125 }
126