src/sleep.c

   1 /* sleep - delay for a specified amount of time.
   2    Copyright (C) 84, 1991-1997, 1999-2005 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  17
  18 #include <config.h>
  19 #include <stdio.h>
  20 #include <assert.h>
  21 #include <sys/types.h>
  22 #include <getopt.h>
  23
  24 #include "system.h"
  25 #include "c-strtod.h"
  26 #include "error.h"
  27 #include "long-options.h"
  28 #include "quote.h"
  29 #include "xnanosleep.h"
  30 #include "xstrtod.h"
  31
  32 /* The official name of this program (e.g., no `g' prefix).  */
  33 #define PROGRAM_NAME "sleep"
  34
  35 #define AUTHORS "Jim Meyering", "Paul Eggert"
  36
  37 /* The name by which this program was run. */
  38 char *program_name;
  39
  40 void
  41 usage (int status)
  42 {
  43   if (status != EXIT_SUCCESS)
  44     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  45              program_name);
  46   else
  47     {
  48       printf (_("\
  49 Usage: %s NUMBER[SUFFIX]...\n\
  50   or:  %s OPTION\n\
  51 Pause for NUMBER seconds.  SUFFIX may be `s' for seconds (the default),\n\
  52 `m' for minutes, `h' for hours or `d' for days.  Unlike most implementations\n\
  53 that require NUMBER be an integer, here NUMBER may be an arbitrary floating\n\
  54 point number.\n\
  55 \n\
  56 "),
  57               program_name, program_name);
  58       fputs (HELP_OPTION_DESCRIPTION, stdout);
  59       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  60       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
  61     }
  62   exit (status);
  63 }
  64
  65 /* Given a floating point value *X, and a suffix character, SUFFIX_CHAR,
  66    scale *X by the multiplier implied by SUFFIX_CHAR.  SUFFIX_CHAR may
  67    be the NUL byte or `s' to denote seconds, `m' for minutes, `h' for
  68    hours, or `d' for days.  If SUFFIX_CHAR is invalid, don't modify *X
  69    and return false.  Otherwise return true.  */
  70
  71 static bool
  72 apply_suffix (double *x, char suffix_char)
  73 {
  74   int multiplier;
  75
  76   switch (suffix_char)
  77     {
  78     case 0:
  79     case 's':
  80       multiplier = 1;
  81       break;
  82     case 'm':
  83       multiplier = 60;
  84       break;
  85     case 'h':
  86       multiplier = 60 * 60;
  87       break;
  88     case 'd':
  89       multiplier = 60 * 60 * 24;
  90       break;
  91     default:
  92       return false;
  93     }
  94
  95   *x *= multiplier;
  96
  97   return true;
  98 }
  99
 100 int
 101 main (int argc, char **argv)
 102 {
 103   int i;
 104   double seconds = 0.0;
 105   bool ok = true;
 106
 107   initialize_main (&argc, &argv);
 108   program_name = argv[0];
 109   setlocale (LC_ALL, "");
 110   bindtextdomain (PACKAGE, LOCALEDIR);
 111   textdomain (PACKAGE);
 112
 113   atexit (close_stdout);
 114
 115   parse_long_options (argc, argv, PROGRAM_NAME, GNU_PACKAGE, VERSION,
 116                       usage, AUTHORS, (char const *) NULL);
 117   if (getopt_long (argc, argv, "", NULL, NULL) != -1)
 118     usage (EXIT_FAILURE);
 119
 120   if (argc == 1)
 121     {
 122       error (0, 0, _("missing operand"));
 123       usage (EXIT_FAILURE);
 124     }
 125
 126   for (i = optind; i < argc; i++)
 127     {
 128       double s;
 129       const char *p;
 130       if (! xstrtod (argv[i], &p, &s, c_strtod)
 131           /* Nonnegative interval.  */
 132           || ! (0 <= s)
 133           /* No extra chars after the number and an optional s,m,h,d char.  */
 134           || (*p && *(p+1))
 135           /* Check any suffix char and update S based on the suffix.  */
 136           || ! apply_suffix (&s, *p))
 137         {
 138           error (0, 0, _("invalid time interval %s"), quote (argv[i]));
 139           ok = false;
 140         }
 141
 142       seconds += s;
 143     }
 144
 145   if (!ok)
 146     usage (EXIT_FAILURE);
 147
 148   if (xnanosleep (seconds))
 149     error (EXIT_FAILURE, errno, _("cannot read realtime clock"));
 150
 151   exit (EXIT_SUCCESS);
 152 }