FS.FILO.Ext2: Update stubs
diff --git a/src/fs-filo-ext2.adb b/src/fs-filo-ext2.adb
index df8525f..730cd11 100644
--- a/src/fs-filo-ext2.adb
+++ b/src/fs-filo-ext2.adb
@@ -4,24 +4,43 @@
 
 package body FS.FILO.Ext2 is
 
-   procedure Mount (Success : out Boolean)
+   function Is_Mounted (State : T) return Boolean is (State.S >= Mounted);
+   function Is_Open (State : T) return Boolean is (State.S = File_Opened);
+
+   procedure Mount
+     (State    : in out T;
+      Part_Len : in     Partition_Length;
+      Success  :    out Boolean)
    is
    begin
       Success := False;
    end Mount;
 
-   procedure Open (File_Path : String; Success : out Boolean)
+   procedure Open
+     (State       : in out T;
+      File_Len    :    out File_Length;
+      File_Path   : in     String;
+      Success     : out    Boolean)
    is
    begin
+      File_Len := 0;
       Success := False;
    end Open;
 
-   procedure Close is null;
+   procedure Close (State : in out T) is
+   begin
+      State.S := Mounted;
+   end Close;
 
-   procedure Read (Buf : out Buffer_Type; Len : out Natural)
+   procedure Read
+     (State    : in out T;
+      File_Len : in     File_Length;
+      File_Pos : in out File_Offset;
+      Buf      :    out Buffer_Type;
+      Len      :    out Natural)
    is
    begin
-      Buf := (others => 16#00#);
+      Buf := (others => 0);
       Len := 0;
    end Read;