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 * 4. 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 30#if 0 31#ifndef lint 32static char const copyright[] = 33"@(#) Copyright (c) 1988, 1993, 1994\n\ 34 The Regents of the University of California. All rights reserved.\n"; 35#endif /* not lint */ 36 37#ifndef lint 38static char sccsid[] = "@(#)sleep.c 8.3 (Berkeley) 4/2/94"; 39#endif /* not lint */ 40#endif 41#include <sys/cdefs.h> 42__FBSDID("$FreeBSD: src/bin/sleep/sleep.c,v 1.20 2005/08/07 09:11:38 stefanf Exp $"); 43 44#include <ctype.h> 45#include <limits.h> 46#include <stdio.h> 47#include <stdlib.h> 48#include <time.h> 49#include <unistd.h> 50#include <string.h> 51 52void usage(void); 53 54int 55main(int argc, char *argv[]) 56{ 57 struct timespec time_to_sleep; 58 long l; 59 int neg; 60 char *p; 61 62 if (argc == 2) { 63 p = argv[1]; 64 } else if (argc == 3 && !strcmp("--", argv[1])) { 65 // POSIX issue: "sleep -- 3" should be the same as "sleep 3", 66 // normally getopt makes this kind of thing work, but sleep has 67 // no options, so we do it "the easy way" 68 p = argv[2]; 69 } else { 70 usage(); 71 return(1); 72 } 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 if (!isdigit((unsigned char)*p) && *p != '.') { 84 usage(); 85 return(1); 86 } 87 } 88 else if (*p == '+') 89 ++p; 90 91 /* Calculate seconds. */ 92 if (isdigit((unsigned char)*p)) { 93 l = strtol(p, &p, 10); 94 if (l > INT_MAX) { 95 /* 96 * Avoid overflow when `seconds' is huge. This assumes 97 * that the maximum value for a time_t is <= INT_MAX. 98 */ 99 l = INT_MAX; 100 } 101 } else 102 l = 0; 103 time_to_sleep.tv_sec = (time_t)l; 104 105 /* Calculate nanoseconds. */ 106 time_to_sleep.tv_nsec = 0; 107 108 if (*p == '.') { /* Decimal point. */ 109 l = 100000000L; 110 do { 111 if (isdigit((unsigned char)*++p)) 112 time_to_sleep.tv_nsec += (*p - '0') * l; 113 else 114 break; 115 l /= 10; 116 } while (l); 117 } 118 119 if (!neg && (time_to_sleep.tv_sec > 0 || time_to_sleep.tv_nsec > 0)) 120 (void)nanosleep(&time_to_sleep, (struct timespec *)NULL); 121 122 return(0); 123} 124 125void 126usage(void) 127{ 128 const char msg[] = "usage: sleep seconds\n"; 129 130 write(STDERR_FILENO, msg, sizeof(msg) - 1); 131} 132