1 /* $OpenBSD: sleep.c,v 1.24 2015/10/11 20:17:49 guenther 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 <ctype.h> 34 #include <errno.h> 35 #include <signal.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <time.h> 39 #include <unistd.h> 40 #include <err.h> 41 42 extern char *__progname; 43 44 void usage(void); 45 void alarmh(int); 46 47 int 48 main(int argc, char *argv[]) 49 { 50 int ch; 51 time_t secs = 0, t; 52 char *cp; 53 long nsecs = 0; 54 struct timespec rqtp; 55 int i; 56 57 if (pledge("stdio", NULL) == -1) 58 err(1, "pledge"); 59 60 signal(SIGALRM, alarmh); 61 62 while ((ch = getopt(argc, argv, "")) != -1) 63 switch(ch) { 64 default: 65 usage(); 66 } 67 argc -= optind; 68 argv += optind; 69 70 if (argc != 1) 71 usage(); 72 73 cp = *argv; 74 while ((*cp != '\0') && (*cp != '.')) { 75 if (!isdigit((unsigned char)*cp)) 76 usage(); 77 t = (secs * 10) + (*cp++ - '0'); 78 if (t / 10 != secs) /* oflow */ 79 return (EINVAL); 80 secs = t; 81 } 82 83 /* Handle fractions of a second */ 84 if (*cp == '.') { 85 cp++; 86 for (i = 100000000; i > 0; i /= 10) { 87 if (*cp == '\0') 88 break; 89 if (!isdigit((unsigned char)*cp)) 90 usage(); 91 nsecs += (*cp++ - '0') * i; 92 } 93 94 /* 95 * We parse all the way down to nanoseconds 96 * in the above for loop. Be pedantic about 97 * checking the rest of the argument. 98 */ 99 while (*cp != '\0') { 100 if (!isdigit((unsigned char)*cp++)) 101 usage(); 102 } 103 } 104 105 rqtp.tv_sec = secs; 106 rqtp.tv_nsec = nsecs; 107 108 if ((secs > 0) || (nsecs > 0)) 109 if (nanosleep(&rqtp, NULL)) 110 err(1, NULL); 111 return (0); 112 } 113 114 void 115 usage(void) 116 { 117 (void)fprintf(stderr, "usage: %s seconds\n", __progname); 118 exit(1); 119 } 120 121 /* 122 * POSIX 1003.2 says sleep should exit with 0 return code on reception 123 * of SIGALRM. 124 */ 125 /* ARGSUSED */ 126 void 127 alarmh(int signo) 128 { 129 /* 130 * exit() flushes stdio buffers, which is not legal in a signal 131 * handler. Use _exit(). 132 */ 133 _exit(0); 134 } 135