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 34 #ifndef lint 35 static char const copyright[] = 36 "@(#) Copyright (c) 1988, 1993, 1994\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)sleep.c 8.3 (Berkeley) 4/2/94"; 43 #endif 44 static const char rcsid[] = 45 "$FreeBSD$"; 46 #endif /* not lint */ 47 48 #include <ctype.h> 49 #include <limits.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <time.h> 53 #include <unistd.h> 54 55 void usage(void); 56 57 int 58 main(int argc, char *argv[]) 59 { 60 struct timespec time_to_sleep; 61 long l; 62 int ch, neg; 63 char *p; 64 65 while ((ch = getopt(argc, argv, "")) != -1) 66 switch(ch) { 67 case '?': 68 default: 69 usage(); 70 /* NOTREACHED */ 71 } 72 argc -= optind; 73 argv += optind; 74 75 if (argc != 1) { 76 usage(); 77 /* NOTREACHED */ 78 } 79 80 p = argv[0]; 81 82 /* Skip over leading whitespaces. */ 83 while (isspace((unsigned char)*p)) 84 ++p; 85 86 /* Check for optional `+' or `-' sign. */ 87 neg = 0; 88 if (*p == '-') { 89 neg = 1; 90 ++p; 91 } 92 else if (*p == '+') 93 ++p; 94 95 /* Calculate seconds. */ 96 if (isdigit((unsigned char)*p)) { 97 l = strtol(p, &p, 10); 98 if (l > INT_MAX) { 99 /* 100 * Avoid overflow when `seconds' is huge. This assumes 101 * that the maximum value for a time_t is >= INT_MAX. 102 */ 103 l = INT_MAX; 104 } 105 } else 106 l = 0; 107 time_to_sleep.tv_sec = (time_t)l; 108 109 /* Calculate nanoseconds. */ 110 time_to_sleep.tv_nsec = 0; 111 112 if (*p == '.') { /* Decimal point. */ 113 l = 100000000L; 114 do { 115 if (isdigit((unsigned char)*++p)) 116 time_to_sleep.tv_nsec += (*p - '0') * l; 117 else 118 break; 119 } while (l /= 10); 120 } 121 122 if (!neg && (time_to_sleep.tv_sec > 0 || time_to_sleep.tv_nsec > 0)) 123 (void)nanosleep(&time_to_sleep, (struct timespec *)NULL); 124 125 exit(0); 126 } 127 128 void 129 usage(void) 130 { 131 132 (void)fprintf(stderr, "usage: sleep seconds\n"); 133 exit(1); 134 } 135