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 1.4 2003/09/28 14:39:15 hmp Exp $ 37 */ 38 39 #include <ctype.h> 40 #include <limits.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <time.h> 44 #include <unistd.h> 45 46 int main (int, char *[]); 47 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 while ((ch = getopt(argc, argv, "")) != -1) 58 switch(ch) { 59 case '?': 60 default: 61 usage(); 62 /* NOTREACHED */ 63 } 64 argc -= optind; 65 argv += optind; 66 67 if (argc != 1) { 68 usage(); 69 /* NOTREACHED */ 70 } 71 72 p = argv[0]; 73 74 /* Skip over leading whitespaces. */ 75 while (isspace((unsigned char)*p)) 76 ++p; 77 78 /* Check for optional `+' or `-' sign. */ 79 neg = 0; 80 if (*p == '-') { 81 neg = 1; 82 ++p; 83 } 84 else if (*p == '+') 85 ++p; 86 87 /* Calculate seconds. */ 88 if (isdigit((unsigned char)*p)) { 89 l = strtol(p, &p, 10); 90 if (l > INT_MAX) { 91 /* 92 * Avoid overflow when `seconds' is huge. This assumes 93 * that the maximum value for a time_t is >= INT_MAX. 94 */ 95 l = INT_MAX; 96 } 97 } else 98 l = 0; 99 time_to_sleep.tv_sec = (time_t)l; 100 101 /* Calculate nanoseconds. */ 102 time_to_sleep.tv_nsec = 0; 103 104 if (*p == '.') { /* Decimal point. */ 105 l = 100000000L; 106 do { 107 if (isdigit((unsigned char)*++p)) 108 time_to_sleep.tv_nsec += (*p - '0') * l; 109 else 110 break; 111 } while (l /= 10); 112 } 113 114 if (!neg && (time_to_sleep.tv_sec > 0 || time_to_sleep.tv_nsec > 0)) 115 (void)nanosleep(&time_to_sleep, (struct timespec *)NULL); 116 117 exit(0); 118 } 119 120 void 121 usage(void) 122 { 123 124 (void)fprintf(stderr, "usage: sleep seconds\n"); 125 exit(1); 126 } 127