src/sleep.c

   1 /* sleep - delay for a specified amount of time.
   2    Copyright (C) 84, 1991-1997, 1999-2002 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 #include <config.h>
  19 #include <stdio.h>
  20 #include <assert.h>
  21 #include <sys/types.h>
  22 #include <time.h>
  23 #include <getopt.h>
  24
  25 #define USE_CLOCK_GETTIME (defined CLOCK_REALTIME && HAVE_CLOCK_GETTIME)
  26 #if ! USE_CLOCK_GETTIME
  27 # include <sys/time.h>
  28 #endif
  29
  30 #ifndef TIME_T_MAX
  31 # define TIME_T_MAX TYPE_MAXIMUM (time_t)
  32 #endif
  33
  34 #include "system.h"
  35 #include "closeout.h"
  36 #include "error.h"
  37 #include "long-options.h"
  38 #include "timespec.h"
  39 #include "xnanosleep.h"
  40 #include "xstrtod.h"
  41
  42 /* The official name of this program (e.g., no `g' prefix).  */
  43 #define PROGRAM_NAME "sleep"
  44
  45 #define AUTHORS N_ ("Jim Meyering and Paul Eggert")
  46
  47 /* The name by which this program was run. */
  48 char *program_name;
  49
  50 static struct option const long_options[] =
  51 {
  52   {0, 0, 0, 0}
  53 };
  54
  55 void
  56 usage (int status)
  57 {
  58   if (status != 0)
  59     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  60              program_name);
  61   else
  62     {
  63       printf (_("\
  64 Usage: %s NUMBER[SUFFIX]...\n\
  65   or:  %s OPTION\n\
  66 Pause for NUMBER seconds.  SUFFIX may be `s' for seconds (the default),\n\
  67 `m' for minutes, `h' for hours or `d' for days.  Unlike most implementations\n\
  68 that require NUMBER be an integer, here NUMBER may be an arbitrary floating\n\
  69 point number.\n\
  70 \n\
  71 "),
  72               program_name, program_name);
  73       fputs (HELP_OPTION_DESCRIPTION, stdout);
  74       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  75       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
  76     }
  77   exit (status);
  78 }
  79
  80 /* Given a floating point value *X, and a suffix character, SUFFIX_CHAR,
  81    scale *X by the multiplier implied by SUFFIX_CHAR.  SUFFIX_CHAR may
  82    be the NUL byte or `s' to denote seconds, `m' for minutes, `h' for
  83    hours, or `d' for days.  If SUFFIX_CHAR is invalid, don't modify *X
  84    and return nonzero.  Otherwise return zero.  */
  85
  86 static int
  87 apply_suffix (double *x, char suffix_char)
  88 {
  89   unsigned int multiplier;
  90
  91   switch (suffix_char)
  92     {
  93     case 0:
  94     case 's':
  95       multiplier = 1;
  96       break;
  97     case 'm':
  98       multiplier = 60;
  99       break;
 100     case 'h':
 101       multiplier = 60 * 60;
 102       break;
 103     case 'd':
 104       multiplier = 60 * 60 * 24;
 105       break;
 106     default:
 107       multiplier = 0;
 108     }
 109
 110   if (multiplier == 0)
 111     return 1;
 112
 113   *x *= multiplier;
 114
 115   return 0;
 116 }
 117
 118 int
 119 main (int argc, char **argv)
 120 {
 121   int i;
 122   double seconds = 0.0;
 123   int c;
 124   int fail = 0;
 125
 126   program_name = argv[0];
 127   setlocale (LC_ALL, "");
 128   bindtextdomain (PACKAGE, LOCALEDIR);
 129   textdomain (PACKAGE);
 130
 131   atexit (close_stdout);
 132
 133   parse_long_options (argc, argv, PROGRAM_NAME, GNU_PACKAGE, VERSION,
 134                       AUTHORS, usage);
 135
 136   while ((c = getopt_long (argc, argv, "", long_options, NULL)) != -1)
 137     {
 138       switch (c)
 139         {
 140         case 0:
 141           break;
 142
 143         default:
 144           usage (EXIT_FAILURE);
 145         }
 146     }
 147
 148   if (argc == 1)
 149     {
 150       error (0, 0, _("too few arguments"));
 151       usage (EXIT_FAILURE);
 152     }
 153
 154   for (i = optind; i < argc; i++)
 155     {
 156       double s;
 157       const char *p;
 158       if (xstrtod (argv[i], &p, &s)
 159           /* Nonnegative interval.  */
 160           || ! (0 <= s)
 161           /* No extra chars after the number and an optional s,m,h,d char.  */
 162           || (*p && *(p+1))
 163           /* Check any suffix char and update S based on the suffix.  */
 164           || apply_suffix (&s, *p))
 165         {
 166           error (0, 0, _("invalid time interval `%s'"), argv[i]);
 167           fail = 1;
 168         }
 169
 170       seconds += s;
 171     }
 172
 173   if (fail)
 174     usage (EXIT_FAILURE);
 175
 176   if (xnanosleep (seconds))
 177     error (EXIT_FAILURE, errno, _("cannot read realtime clock"));
 178
 179   exit (EXIT_SUCCESS);
 180 }