text: /*
   *  GRUB  --  GRand Unified Bootloader
   *  Copyright (C) 2009  Free Software Foundation, Inc.
   *
   *  GRUB is free software: you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  GRUB is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  #include <grub/env.h>
  #include <grub/misc.h>
  #include <grub/disk.h>
  #include <grub/machine/biosnum.h>
  
  static int
  grub_get_root_biosnumber_default (void)
  {
    const char *biosnum;
    int ret = -1;
    grub_device_t dev;
  
    biosnum = grub_env_get ("biosnum");
  
    if (biosnum)
      return grub_strtoul (biosnum, 0, 0);
  
    dev = grub_device_open (0);
    if (dev && dev->disk && dev->disk->dev
        && dev->disk->dev->id == GRUB_DISK_DEVICE_BIOSDISK_ID)
      ret = (int) dev->disk->id;
  
    if (dev)
      grub_device_close (dev);
  
    return ret;
  }
  
  int (*grub_get_root_biosnumber) (void) = grub_get_root_biosnumber_default;
  