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