1 files changed, 47 insertions, 0 deletions
diff --git a/grub-core/lib/i386/pc/biosnum.c b/grub-core/lib/i386/pc/biosnum.c
new file mode 100644
index 0000000..0f0e743
--- /dev/null
+++ b/grub-core/lib/i386/pc/biosnum.c
@@ -0,0 +1,47 @@
+/*
+ *  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;