1 /* 2 * Copyright (c) 1988, 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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#) Copyright (c) 1988, 1993, 1994 The Regents of the University of California. All rights reserved. 34 * @(#)sleep.c 8.3 (Berkeley) 4/2/94 35 * $FreeBSD: src/bin/sleep/sleep.c,v 1.9.2.1 2001/08/01 05:23:25 obrien Exp $ 36 * $DragonFly: src/bin/sleep/sleep.c,v 1.7 2005/02/27 15:57:15 liamfoy Exp $ 37 */ 38 39 #include <ctype.h> 40 #include <limits.h> 41 #include <locale.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <time.h> 45 #include <unistd.h> 46 47 static void usage(void); 48 49 int 50 main(int argc, char **argv) 51 { 52 struct timespec time_to_sleep; 53 long l; 54 int ch, neg; 55 char *p; 56 57 setlocale(LC_ALL, ""); 58 59 while ((ch = getopt(argc, argv, "")) != -1) 60 switch(ch) { 61 default: 62 usage(); 63 /* NOTREACHED */ 64 } 65 argc -= optind; 66 argv += optind; 67 68 if (argc != 1) { 69 usage(); 70 /* NOTREACHED */ 71 } 72 73 p = argv[0]; 74 75 /* Skip over leading whitespaces. */ 76 while (isspace(*p)) 77 ++p; 78 79 /* Check for optional `+' or `-' sign. */ 80 neg = 0; 81 if (*p == '-') { 82 neg = 1; 83 ++p; 84 } 85 else if (*p == '+') 86 ++p; 87 88 /* Calculate seconds. */ 89 if (isdigit(*p)) { 90 l = strtol(p, &p, 10); 91 if (l > INT_MAX) { 92 /* 93 * Avoid overflow when `seconds' is huge. This assumes 94 * that the maximum value for a time_t is <= INT_MAX. 95 */ 96 l = INT_MAX; 97 } 98 } else 99 l = 0; 100 time_to_sleep.tv_sec = (time_t)l; 101 102 /* Calculate nanoseconds. */ 103 time_to_sleep.tv_nsec = 0; 104 105 if (*p == '.') { /* Decimal point. */ 106 l = 100000000L; 107 do { 108 if (isdigit(*++p)) 109 time_to_sleep.tv_nsec += (*p - '0') * l; 110 else 111 break; 112 } while (l /= 10); 113 } 114 115 if (!neg && (time_to_sleep.tv_sec > 0 || time_to_sleep.tv_nsec > 0)) 116 nanosleep(&time_to_sleep, (struct timespec *)NULL); 117 118 exit(0); 119 } 120 121 static void 122 usage(void) 123 { 124 fprintf(stderr, "usage: sleep seconds\n"); 125 exit(1); 126 } 127