sleep/sleep.c

   1 /*      $NetBSD: sleep.c,v 1.15 1998/07/28 11:41:58 mycroft Exp $       */
   2
   3 /*
   4  * Copyright (c) 1988, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <sys/cdefs.h>
  37 #ifndef lint
  38 __COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\n\
  39         The Regents of the University of California.  All rights reserved.\n");
  40 #endif /* not lint */
  41
  42 #ifndef lint
  43 #if 0
  44 static char sccsid[] = "@(#)sleep.c     8.3 (Berkeley) 4/2/94";
  45 #else
  46 __RCSID("$NetBSD: sleep.c,v 1.15 1998/07/28 11:41:58 mycroft Exp $");
  47 #endif
  48 #endif /* not lint */
  49
  50 #include <time.h>
  51 #include <ctype.h>
  52 #include <math.h>
  53 #include <signal.h>
  54 #include <stdio.h>
  55 #include <stdlib.h>
  56 #include <unistd.h>
  57 #include <locale.h>
  58
  59 void usage __P((void));
  60 void alarmhandle __P((int));
  61 int  main __P((int, char *[]));
  62
  63 int
  64 main(argc, argv)
  65         int argc;
  66         char *argv[];
  67 {
  68         char *arg, *temp;
  69         double val, ival, fval;
  70         struct timespec ntime;
  71         int fracflag;
  72         int ch;
  73
  74         (void)setlocale(LC_ALL, "");
  75
  76         (void)signal(SIGALRM, alarmhandle);
  77
  78         while ((ch = getopt(argc, argv, "")) != -1)
  79                 switch(ch) {
  80                 case '?':
  81                 default:
  82                         usage();
  83                 }
  84         argc -= optind;
  85         argv += optind;
  86
  87         if (argc != 1)
  88                 usage();
  89
  90         /*
  91          * Okay, why not just use atof for everything? Why bother
  92          * checking if there is a fraction in use? Because the old
  93          * sleep handled the full range of integers, that's why, and a
  94          * double can't handle a large long. This is fairly useless
  95          * given how large a number a double can hold on most
  96          * machines, but now we won't ever have trouble. If you want
  97          * 1000000000.9 seconds of sleep, well, that's your
  98          * problem. Why use an isdigit() check instead of checking for
  99          * a period? Because doing it this way means locales will be
 100          * handled transparently by the atof code.
 101          */
 102         fracflag = 0;
 103         arg = *argv;
 104         for (temp = arg; *temp != '\0'; temp++)
 105                 if (!isdigit(*temp))
 106                         fracflag++;
 107
 108         if (fracflag) {
 109                 val = atof(arg);
 110                 if (val <= 0)
 111                         exit(0);
 112                 ival = floor(val);
 113                 fval = (1000000000 * (val-ival));
 114                 ntime.tv_sec = ival;
 115                 ntime.tv_nsec = fval;
 116         }
 117         else{
 118                 ntime.tv_sec = atol(arg);
 119                 if (ntime.tv_sec <= 0)
 120                         exit(0);
 121                 ntime.tv_nsec = 0;
 122         }
 123
 124         (void)nanosleep(&ntime, NULL);
 125
 126         exit(0);
 127         /* NOTREACHED */
 128 }
 129
 130 void
 131 usage()
 132 {
 133         (void)fputs("usage: sleep seconds\n", stderr);
 134         exit(1);
 135         /* NOTREACHED */
 136 }
 137
 138 /* ARGSUSED */
 139 void
 140 alarmhandle(i)
 141         int i;
 142 {
 143         _exit(0);
 144         /* NOTREACHED */
 145 }