arch/common/boot/grub2/commands/read.c

   1 /* read.c - Command to read variables from user.  */
   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/misc.h>
  22 #include <grub/mm.h>
  23 #include <grub/normal.h>
  24 #include <grub/term.h>
  25 #include <grub/types.h>
  26
  27 static char *
  28 grub_getline (void)
  29 {
  30   int i;
  31   char *line;
  32   char *tmp;
  33   char c;
  34
  35   i = 0;
  36   line = grub_malloc (1 + i + sizeof('\0'));
  37   if (! line)
  38     return NULL;
  39
  40   while (1)
  41     {
  42       c = grub_getkey ();
  43       if ((c == '\n') || (c == '\r'))
  44         break;
  45
  46       line[i] = c;
  47       if (grub_isprint (c))
  48         grub_putchar (c);
  49       i++;
  50       tmp = grub_realloc (line, 1 + i + sizeof('\0'));
  51       if (! tmp)
  52         {
  53           grub_free (line);
  54           return NULL;
  55         }
  56       line = tmp;
  57     }
  58   line[i] = '\0';
  59
  60   return line;
  61 }
  62
  63 static grub_err_t
  64 grub_cmd_read (struct grub_arg_list *state UNUSED, int argc, char **args)
  65 {
  66   char *line = grub_getline ();
  67   if (! line)
  68     return grub_errno;
  69   if (argc > 0)
  70     grub_env_set (args[0], line);
  71
  72   grub_free (line);
  73   return 0;
  74 }
  75
  76 \f
  77 GRUB_MOD_INIT(read)
  78 {
  79   grub_register_command ("read", grub_cmd_read, GRUB_COMMAND_FLAG_CMDLINE,
  80                          "read [ENVVAR]", "Set variable with user input", 0);
  81 }
  82
  83 GRUB_MOD_FINI(read)
  84 {
  85   grub_unregister_command ("read");
  86 }