grub-core/commands/sleep.c

   1 /* sleep.c - Command to wait a specified number of seconds.  */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2006,2007,2008  Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <grub/dl.h>
  21 #include <grub/term.h>
  22 #include <grub/time.h>
  23 #include <grub/types.h>
  24 #include <grub/misc.h>
  25 #include <grub/extcmd.h>
  26 #include <grub/i18n.h>
  27
  28 GRUB_MOD_LICENSE ("GPLv3+");
  29
  30 static const struct grub_arg_option options[] =
  31   {
  32     {"verbose", 'v', 0, N_("Verbose countdown."), 0, 0},
  33     {"interruptible", 'i', 0, N_("Allow to interrupt with ESC."), 0, 0},
  34     {0, 0, 0, 0, 0, 0}
  35   };
  36
  37 static grub_uint16_t *pos;
  38
  39 static void
  40 do_print (int n)
  41 {
  42   grub_term_restore_pos (pos);
  43   /* NOTE: Do not remove the trailing space characters.
  44      They are required to clear the line.  */
  45   grub_printf ("%d    ", n);
  46 }
  47
  48 /* Based on grub_millisleep() from kern/generic/millisleep.c.  */
  49 static int
  50 grub_interruptible_millisleep (grub_uint32_t ms)
  51 {
  52   grub_uint64_t start;
  53
  54   start = grub_get_time_ms ();
  55
  56   while (grub_get_time_ms () - start < ms)
  57     if (grub_getkey_noblock () == GRUB_TERM_ESC)
  58       return 1;
  59
  60   return 0;
  61 }
  62
  63 static grub_err_t
  64 grub_cmd_sleep (grub_extcmd_context_t ctxt, int argc, char **args)
  65 {
  66   struct grub_arg_list *state = ctxt->state;
  67   int n;
  68
  69   if (argc != 1)
  70     return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));
  71
  72   n = grub_strtoul (args[0], 0, 10);
  73
  74   if (n == 0)
  75     {
  76       /* Either `0' or broken input.  */
  77       return 0;
  78     }
  79
  80   pos = grub_term_save_pos ();
  81
  82   for (; n; n--)
  83     {
  84       if (state[0].set)
  85         do_print (n);
  86
  87       if (state[1].set)
  88         {
  89           if (grub_interruptible_millisleep (1000))
  90             return 1;
  91         }
  92       else
  93         grub_millisleep (1000);
  94     }
  95   if (state[0].set)
  96     do_print (0);
  97
  98   return 0;
  99 }
 100
 101 static grub_extcmd_t cmd;
 102 \f
 103 GRUB_MOD_INIT(sleep)
 104 {
 105   cmd = grub_register_extcmd ("sleep", grub_cmd_sleep, 0,
 106                               N_("NUMBER_OF_SECONDS"),
 107                               N_("Wait for a specified number of seconds."),
 108                               options);
 109 }
 110
 111 GRUB_MOD_FINI(sleep)
 112 {
 113   grub_unregister_extcmd (cmd);
 114 }