coreutils/sleep.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * sleep implementation for busybox
   4  *
   5  * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9 /* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  10  *
  11  * Rewritten to do proper arg and error checking.
  12  * Also, added a 'fancy' configuration to accept multiple args with
  13  * time suffixes for seconds, minutes, hours, and days.
  14  */
  15 //config:config SLEEP
  16 //config:       bool "sleep (2.4 kb)"
  17 //config:       default y
  18 //config:       help
  19 //config:       sleep is used to pause for a specified number of seconds.
  20 //config:       It comes in 2 versions:
  21 //config:       - small: takes one integer parameter
  22 //config:       - fancy:
  23 //config:               * takes multiple integer arguments with suffixes:
  24 //config:                       sleep 1d 2h 3m 15s
  25 //config:               * allows fractional numbers:
  26 //config:                       sleep 2.3s 4.5h sleeps for 16202.3 seconds
  27 //config:       fancy is more compatible with coreutils sleep, but it adds around
  28 //config:       1k of code.
  29 //config:
  30 //config:config FEATURE_FANCY_SLEEP
  31 //config:       bool "Enable multiple arguments and s/m/h/d suffixes"
  32 //config:       default y
  33 //config:       depends on SLEEP
  34 //config:       help
  35 //config:       Allow sleep to pause for specified minutes, hours, and days.
  36
  37 /* Do not make this applet NOFORK. It breaks ^C-ing of pauses in shells */
  38 //applet:IF_SLEEP(APPLET(sleep, BB_DIR_BIN, BB_SUID_DROP))
  39
  40 //kbuild:lib-$(CONFIG_SLEEP) += sleep.o
  41 //kbuild:lib-$(CONFIG_ASH_SLEEP) += sleep.o
  42
  43 /* BB_AUDIT SUSv3 compliant */
  44 /* BB_AUDIT GNU issues -- fancy version matches except args must be ints. */
  45 /* http://www.opengroup.org/onlinepubs/007904975/utilities/sleep.html */
  46
  47 //usage:#define sleep_trivial_usage
  48 //usage:        IF_FEATURE_FANCY_SLEEP("[") "N" IF_FEATURE_FANCY_SLEEP("]...")
  49 //usage:#define sleep_full_usage "\n\n"
  50 //usage:        IF_NOT_FEATURE_FANCY_SLEEP("Pause for N seconds")
  51 //usage:        IF_FEATURE_FANCY_SLEEP(
  52 //usage:       "Pause for a time equal to the total of the args given, where each arg can\n"
  53 //usage:       "have an optional suffix of (s)econds, (m)inutes, (h)ours, or (d)ays")
  54 //usage:
  55 //usage:#define sleep_example_usage
  56 //usage:       "$ sleep 2\n"
  57 //usage:       "[2 second delay results]\n"
  58 //usage:        IF_FEATURE_FANCY_SLEEP(
  59 //usage:       "$ sleep 1d 3h 22m 8s\n"
  60 //usage:       "[98528 second delay results]\n")
  61
  62 #include "libbb.h"
  63
  64 int sleep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  65 int sleep_main(int argc UNUSED_PARAM, char **argv)
  66 {
  67         duration_t duration;
  68
  69         /* Note: sleep_main may be directly called from ash as a builtin.
  70          * This brings some complications:
  71          * + we can't use xfunc here
  72          * + we can't use bb_show_usage
  73          * + applet_name can be the name of the shell
  74          */
  75         argv = skip_dash_dash(argv);
  76         if (!argv[0]) {
  77                 /* Without this, bare "sleep" in ash shows _ash_ --help */
  78                 /* (ash can be the "sh" applet as well, so check 2nd char) */
  79                 if (ENABLE_ASH_SLEEP && applet_name[1] != 'l') {
  80                         bb_simple_error_msg("sleep: missing operand");
  81                         return EXIT_FAILURE;
  82                 }
  83                 bb_show_usage();
  84         }
  85
  86         /* GNU sleep accepts "inf", "INF", "infinity" and "INFINITY" */
  87         if (strncasecmp(argv[0], "inf", 3) == 0)
  88                 for (;;)
  89                         sleep(INT_MAX);
  90
  91 //FIXME: in ash, "sleep 123qwerty" as a builtin aborts the shell
  92 #if ENABLE_FEATURE_FANCY_SLEEP
  93         duration = 0;
  94         do {
  95                 duration += parse_duration_str(*argv);
  96         } while (*++argv);
  97         sleep_for_duration(duration);
  98 #else /* simple */
  99         duration = xatou(*argv);
 100         sleep(duration);
 101 #endif
 102         return EXIT_SUCCESS;
 103 }