From 9f2f979bcf7bfd6cef08c17b5a432444ac8603dc Mon Sep 17 00:00:00 2001
From: Andrey Borzenkov <arvidjaar@gmail.com>
Date: Tue, 10 Dec 2013 09:55:27 +0400
Subject: [PATCH] always define config_directory and config_file as full
 pathname

If configfile is relative pathname, extend it with current ($root) so its
interpretation does not change if $root is changed later.

Suggested by Vladimir Serbienko.
---
 grub-core/normal/main.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/grub-core/normal/main.c b/grub-core/normal/main.c
index 991a59524..84df3601f 100644
--- a/grub-core/normal/main.c
+++ b/grub-core/normal/main.c
@@ -190,14 +190,26 @@ read_config_file (const char *config)
   ctmp = grub_env_get ("config_directory");
   if (ctmp)
     old_dir = grub_strdup (ctmp);
-  grub_env_set ("config_file", config);
-  config_dir = grub_strdup (config);
+  if (*config == '(')
+    {
+      grub_env_set ("config_file", config);
+      config_dir = grub_strdup (config);
+    }
+  else
+    {
+      /* $root is guranteed to be defined, otherwise open above would fail */
+      config_dir = grub_xasprintf ("(%s)%s", grub_env_get ("root"), config);
+      if (config_dir)
+	grub_env_set ("config_file", config_dir);
+    }
   if (config_dir)
-    ptr = grub_strrchr (config_dir, '/');
-  if (ptr)
-    *ptr = 0;
-  grub_env_set ("config_directory", config_dir);
-  grub_free (config_dir);
+    {
+      ptr = grub_strrchr (config_dir, '/');
+      if (ptr)
+	*ptr = 0;
+      grub_env_set ("config_directory", config_dir);
+      grub_free (config_dir);
+    }
 
   grub_env_export ("config_file");
   grub_env_export ("config_directory");