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130 | -- --
-- package Copyright (c) Dmitry A. Kazakov --
-- Test_Persistent_File_Storage Luebeck --
-- Interface Autumn, 2004 --
-- --
-- Last revision : 23:22 29 Sep 2017 --
-- --
-- This library 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 2 of --
-- the License, or (at your option) any later version. This library --
-- 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 --
-- this library; if not, write to the Free Software Foundation, --
-- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. --
-- --
-- As a special exception, if other files instantiate generics from --
-- this unit, or you link this unit with other files to produce an --
-- executable, this unit does not by itself cause the resulting --
-- executable to be covered by the GNU General Public License. This --
-- exception does not however invalidate any other reasons why the --
-- executable file might be covered by the GNU Public License. --
--____________________________________________________________________--
with Ada.Direct_IO;
with Ada.Finalization;
with Generic_Map;
with Object.Handle;
with Object.Archived; use Object.Archived;
with Deposit_Handles; use Deposit_Handles;
package Test_Persistent_File_Storage is
--
-- File_Storage -- Direct I/O based storage for persistent objects
--
type File_Storage is
new Ada.Finalization.Limited_Controlled with private;
--
-- Key -- To reference stored objects = record number 1..
--
type Key is new Integer;
subtype Deposit_Handle is Deposit_Handles.Handle;
procedure Initialize (Storage : in out File_Storage);
procedure Finalize (Storage : in out File_Storage);
procedure Clean_Up;
function Store
( Storage : access File_Storage;
Object : Deposit_Handle
) return Key;
function Restore
( Storage : access File_Storage;
ID : Key
) return Deposit_Handle;
private
--
-- Index_Record -- One per bound object
--
type Index_Record (Storage : access File_Storage) is
new Backward_Link with
record
ID : Key; -- Object identifier
end record;
type Index_Record_Ptr is access all Index_Record'Class;
--
-- Implementation of Backward_Link's operation
--
procedure Deleted
( Link : in out Index_Record;
Temps : in out Deposit_Container'Class
);
procedure Destroyed (Link : in out Index_Record);
--
-- Record_Handles -- Handles to index records
--
package Record_Handles is
new Object.Handle (Index_Record, Index_Record_Ptr);
use Record_Handles;
subtype Record_Handle is Record_Handles.Handle;
--
-- Map : object pointer -> record handle
--
function "<" (Left, Right : Deposit_Ptr) return Boolean;
package Object_Maps is
new Generic_Map
( Key_Type => Deposit_Ptr,
Object_Type => Record_Handle
);
use Object_Maps;
subtype Object_Map is Object_Maps.Map;
--
-- Map : object key -> record handle
--
package Key_Maps is
new Generic_Map
( Key_Type => Key,
Object_Type => Record_Handle
);
use Key_Maps;
subtype Key_Map is Key_Maps.Map;
--
-- File record
--
type Reference_List is array (Integer range 1..256) of Key;
type File_Record is record
Length : Natural := 0;
Count : Natural := 0;
References : Reference_List;
Descriptor : String (1..1024);
end record;
package Record_Files is new Ada.Direct_IO (File_Record);
use Record_Files;
--
-- File_Storage -- Implementation
--
type File_Storage is
new Ada.Finalization.Limited_Controlled with
record
File : File_Type;
Object_To_Record : Object_Map;
Key_To_Record : Key_Map;
Last_ID : Key := 0; -- Last used object key
end record;
end Test_Persistent_File_Storage;
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