1  /* sleep - delay for a specified amount of time.
       2     Copyright (C) 1984-2023 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 3 of the License, or
       7     (at your option) 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, see <https://www.gnu.org/licenses/>.  */
      16  
      17  #include <config.h>
      18  #include <stdio.h>
      19  #include <sys/types.h>
      20  
      21  #include "system.h"
      22  #include "cl-strtod.h"
      23  #include "long-options.h"
      24  #include "quote.h"
      25  #include "xnanosleep.h"
      26  #include "xstrtod.h"
      27  
      28  /* The official name of this program (e.g., no 'g' prefix).  */
      29  #define PROGRAM_NAME "sleep"
      30  
      31  #define AUTHORS \
      32    proper_name ("Jim Meyering"), \
      33    proper_name ("Paul Eggert")
      34  
      35  void
      36  usage (int status)
      37  {
      38    if (status != EXIT_SUCCESS)
      39      emit_try_help ();
      40    else
      41      {
      42        printf (_("\
      43  Usage: %s NUMBER[SUFFIX]...\n\
      44    or:  %s OPTION\n\
      45  Pause for NUMBER seconds.  SUFFIX may be 's' for seconds (the default),\n\
      46  'm' for minutes, 'h' for hours or 'd' for days.  NUMBER need not be an\n\
      47  integer.  Given two or more arguments, pause for the amount of time\n\
      48  specified by the sum of their values.\n\
      49  \n\
      50  "),
      51                program_name, program_name);
      52        fputs (HELP_OPTION_DESCRIPTION, stdout);
      53        fputs (VERSION_OPTION_DESCRIPTION, stdout);
      54        emit_ancillary_info (PROGRAM_NAME);
      55      }
      56    exit (status);
      57  }
      58  
      59  /* Given a floating point value *X, and a suffix character, SUFFIX_CHAR,
      60     scale *X by the multiplier implied by SUFFIX_CHAR.  SUFFIX_CHAR may
      61     be the NUL byte or 's' to denote seconds, 'm' for minutes, 'h' for
      62     hours, or 'd' for days.  If SUFFIX_CHAR is invalid, don't modify *X
      63     and return false.  Otherwise return true.  */
      64  
      65  static bool
      66  apply_suffix (double *x, char suffix_char)
      67  {
      68    int multiplier;
      69  
      70    switch (suffix_char)
      71      {
      72      case 0:
      73      case 's':
      74        multiplier = 1;
      75        break;
      76      case 'm':
      77        multiplier = 60;
      78        break;
      79      case 'h':
      80        multiplier = 60 * 60;
      81        break;
      82      case 'd':
      83        multiplier = 60 * 60 * 24;
      84        break;
      85      default:
      86        return false;
      87      }
      88  
      89    *x *= multiplier;
      90  
      91    return true;
      92  }
      93  
      94  int
      95  main (int argc, char **argv)
      96  {
      97    double seconds = 0.0;
      98    bool ok = true;
      99  
     100    initialize_main (&argc, &argv);
     101    set_program_name (argv[0]);
     102    setlocale (LC_ALL, "");
     103    bindtextdomain (PACKAGE, LOCALEDIR);
     104    textdomain (PACKAGE);
     105  
     106    atexit (close_stdout);
     107  
     108    parse_gnu_standard_options_only (argc, argv, PROGRAM_NAME, PACKAGE_NAME,
     109                                     Version, true, usage, AUTHORS,
     110                                     (char const *) nullptr);
     111  
     112    if (argc == 1)
     113      {
     114        error (0, 0, _("missing operand"));
     115        usage (EXIT_FAILURE);
     116      }
     117  
     118    for (int i = optind; i < argc; i++)
     119      {
     120        double s;
     121        char const *p;
     122        if (! (xstrtod (argv[i], &p, &s, cl_strtod) || errno == ERANGE)
     123            /* Nonnegative interval.  */
     124            || ! (0 <= s)
     125            /* No extra chars after the number and an optional s,m,h,d char.  */
     126            || (*p && *(p + 1))
     127            /* Check any suffix char and update S based on the suffix.  */
     128            || ! apply_suffix (&s, *p))
     129          {
     130            error (0, 0, _("invalid time interval %s"), quote (argv[i]));
     131            ok = false;
     132          }
     133  
     134        seconds += s;
     135      }
     136  
     137    if (!ok)
     138      usage (EXIT_FAILURE);
     139  
     140    if (xnanosleep (seconds))
     141      error (EXIT_FAILURE, errno, _("cannot read realtime clock"));
     142  
     143    return EXIT_SUCCESS;
     144  }