normal/menu_viewer.c

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 2009  Free Software Foundation, Inc.
   4  *
   5  *  GRUB is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  GRUB is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <grub/mm.h>
  20 #include <grub/misc.h>
  21 #include <grub/env.h>
  22 #include <grub/menu_viewer.h>
  23 #include <grub/menu.h>
  24
  25 /* The list of menu viewers.  */
  26 static grub_menu_viewer_t menu_viewer_list;
  27
  28 void
  29 grub_menu_viewer_register (grub_menu_viewer_t viewer)
  30 {
  31   viewer->next = menu_viewer_list;
  32   menu_viewer_list = viewer;
  33 }
  34
  35 static grub_menu_viewer_t get_current_menu_viewer (void)
  36 {
  37   const char *selected_name = grub_env_get ("menuviewer");
  38
  39   /* If none selected, pick the last registered one. */
  40   if (selected_name == 0)
  41     return menu_viewer_list;
  42
  43   grub_menu_viewer_t cur;
  44   for (cur = menu_viewer_list; cur; cur = cur->next)
  45     {
  46       if (grub_strcmp (cur->name, selected_name) == 0)
  47         return cur;
  48     }
  49
  50   /* Fall back to the first entry (or null).  */
  51   return menu_viewer_list;
  52 }
  53
  54 grub_err_t
  55 grub_menu_viewer_show_menu (grub_menu_t menu, int nested)
  56 {
  57   grub_menu_viewer_t cur = get_current_menu_viewer ();
  58   if (!cur)
  59     return grub_error (GRUB_ERR_BAD_ARGUMENT, "No menu viewer available.");
  60
  61   return cur->show_menu (menu, nested);
  62 }
  63