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1352 | -- --
-- package Copyright (c) Dmitry A. Kazakov --
-- Persistent.Data_Bank.Index Luebeck --
-- Implementation Autumn, 2004 --
-- --
-- Last revision : 22:45 07 Apr 2016 --
-- --
-- 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.IO_Exceptions; use Ada.IO_Exceptions;
with Ada.Tags; use Ada.Tags;
with Strings_Edit.Quoted; use Strings_Edit.Quoted;
with Object; use Object;
package body Persistent.Data_Bank.Index is
use Ptr_Map;
use Key_Map;
use Name_Map;
--
-- Create -- New catalogue record
--
-- List - The catalogue
-- Object - The object
-- External - The object's key
-- Name - The object's name
-- Parent - The object's parent
--
procedure Create
( List : in out Catalogue;
Object : Deposit_Ptr;
External : Key;
Name : String;
Parent : Catalogue_Record_Ptr
);
--
-- Delete -- A catalogue record
--
-- List - The catalogue
-- Item - The record to be deleted (a pointer to)
--
procedure Delete
( List : in out Catalogue;
Item : Catalogue_Record_Ptr
);
--
-- Notify_Deletion_By_Key -- Notify objects holding backward links
--
-- List - The catalogue
-- Object - The key of the object being deleted
--
procedure Notify_Deletion_By_Key
( List : in out Catalogue;
Object : Key
);
function "<" (Left, Right : By_Name_Ptr) return Boolean is
begin
if Equal (Right, null) then
return False;
elsif Equal (Left, null) then
return True;
elsif Left.Parent = Right.Parent then
return Left.Name < Right.Name;
else
return By_Key_Ptr (Left.Parent) < By_Key_Ptr (Right.Parent);
end if;
end "<";
function "<" (Left, Right : By_Entity_Ptr) return Boolean is
begin
if Equal (Right, null) then
return False;
elsif Equal (Left, null) then
return True;
else
if Left.all in Catalogue_Record'Class then
if Right.all in Catalogue_Record'Class then
return
Less
( This (Catalogue_Record'Class (Left.all )).all,
This (Catalogue_Record'Class (Right.all)).all
);
else
return
Less
( This (Catalogue_Record'Class (Left.all)).all,
Right.all
);
end if;
else
if Right.all in Catalogue_Record'Class then
return
Less
( Left.all,
This (Catalogue_Record'Class (Right.all)).all
);
else
return Less (Left.all, Right.all);
end if;
end if;
end if;
end "<";
function "<" (Left, Right : By_Key_Ptr) return Boolean is
begin
if Equal (Right, null) then
return False;
elsif Equal (Left, null) then
return True;
else
return Left.External < Right.External;
end if;
end "<";
function "=" (Left, Right : By_Name_Ptr) return Boolean is
begin
if Equal (Left, null) then
return Equal (Right, null);
elsif Equal (Right, null) then
return False;
else
return
( Left.Parent = Right.Parent
and then
Left.Name = Right.Name
);
end if;
end "=";
function "=" (Left, Right : By_Entity_Ptr) return Boolean is
begin
if Equal (Left, null) then
return Equal (Right, null);
elsif Equal (Right, null) then
return False;
else
if Left.all in Catalogue_Record'Class then
if Right.all in Catalogue_Record'Class then
return
Equal
( This (Catalogue_Record'Class (Left.all )).all,
This (Catalogue_Record'Class (Right.all)).all
);
else
return
Equal
( This (Catalogue_Record'Class (Left.all)).all,
Right.all
);
end if;
else
if Right.all in Catalogue_Record'Class then
return
Object.Equal
( Left.all,
This (Catalogue_Record'Class (Right.all)).all
);
else
return Object.Equal (Left.all, Right.all);
end if;
end if;
end if;
end "=";
function "=" (Left, Right : By_Key_Ptr) return Boolean is
begin
if Equal (Left, null) then
return Equal (Right, null);
elsif Equal (Right, null) then
return False;
else
return Left.External = Right.External;
end if;
end "=";
procedure Add
( List : in out Catalogue;
Object : Deposit_Ptr;
External : Key;
Name : String;
Parent : Key
) is
begin
if Name'Length = 0 then
Raise_Exception
( Name_Error'Identity,
"No empty names allowed"
);
end if;
if Parent = Null_Key then
Create (List, Object, External, Name, null);
else
declare
Index : constant Integer := Find (List, Parent);
begin
if Index < 0 then
Raise_Exception
( Constraint_Error'Identity,
( "Parent "
& Image (List.Storage.all, Parent)
& " of "
& Image (List.Storage.all, External)
& " does not persist"
) );
end if;
declare
Parent_Ptr : constant Catalogue_Record_Ptr :=
Catalogue_Record_Ptr (Get (List.By_Key, Index));
begin
if Parent_Ptr.Name_Length = 0 then
Raise_Exception
( Name_Error'Identity,
( "Parent "
& Image (List.Storage.all, Parent)
& " of "
& Image (List.Storage.all, External)
& " is anonymous"
) );
end if;
Create (List, Object, External, Name, Parent_Ptr);
end;
end;
end if;
end Add;
procedure Add
( List : in out Catalogue;
Object : Deposit_Ptr;
External : Key
) is
begin
Create (List, Object, External, "", null);
end Add;
procedure Create
( List : in out Catalogue;
Object : Deposit_Ptr;
External : Key;
Name : String;
Parent : Catalogue_Record_Ptr
) is
Index : Integer;
begin
Index := Find (List.By_Ptr, By_Entity_Ptr (Object));
if Index > 0 then
--
-- The object already bound. We check if it has the properties
-- requested.
--
declare
Item : Catalogue_Record renames
Catalogue_Record (Get (List.By_Ptr, Index).all);
begin
if Name /= Item.Name then
Raise_Exception
( Name_Error'Identity,
( "Object "
& Image (List.Storage.all, External)
& " is already bound as "
& Quote (Item.Name)
) );
elsif Parent /= Item.Parent then
Raise_Exception
( Name_Error'Identity,
( "Object "
& Image (List.Storage.all, External)
& ", child of "
& Image (List.Storage.all, Item.Parent.External)
& " is already child of "
& Image (List.Storage.all, Parent.External)
) );
elsif External /= Item.External then
Raise_Exception
( Name_Error'Identity,
( "Object "
& Image (List.Storage.all, External)
& " is bound under other key "
& Image (List.Storage.all, Item.External)
) );
end if;
end;
else
--
-- The object is not bound, so we create a record for it
--
declare
Link : constant Backward_Link_Ptr :=
new Catalogue_Record (Name'Length);
Item : Catalogue_Record renames Catalogue_Record (Link.all);
begin
Increment_Count (Item);
Attach (Link, Object);
Item.List := List'Unchecked_Access;
Item.External := External;
Item.Name := Name;
if Parent /= null then
Item.Parent := Parent;
Increment_Count (This (Parent.all).all);
end if;
Add (List.By_Ptr, Item'Unchecked_Access);
Add (List.By_Key, Item'Unchecked_Access);
if Name'Length /= 0 then
Add (List.By_Name, Item'Unchecked_Access);
end if;
exception
when others =>
Delete (List, Item'Unchecked_Access);
raise;
end;
end if;
end Create;
procedure Delete
( List : in out Catalogue;
Item : Catalogue_Record_Ptr
) is
begin
if Item /= null then
Remove (List.By_Ptr, By_Entity_Ptr (Item));
Remove (List.By_Key, By_Key_Ptr (Item));
Remove (List.By_Name, By_Name_Ptr (Item));
if Item.Parent /= null then
declare
Ptr : Object.Entity_Ptr :=
Object.Entity_Ptr (This (Item.Parent.all));
begin
Item.Parent := null;
Object.Release (Ptr);
end;
end if;
Detach (Item.all);
declare
Ptr : Object.Entity_Ptr := Object.Entity_Ptr (Item);
begin
Object.Release (Ptr);
end;
end if;
end Delete;
procedure Delete (List : in out Catalogue; ID : Deposit_Ptr) is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
Delete
( List,
Catalogue_Record
( Get (List.By_Ptr, Index).all
) 'Unchecked_Access
);
end if;
end Delete;
procedure Delete (List : in out Catalogue; ID : Key) is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
Delete
( List,
Catalogue_Record_Ptr (Get (List.By_Key, Index))
);
end if;
end Delete;
procedure Delete
( List : in out Catalogue;
Name : String;
Parent : Deposit_Ptr
) is
Index : constant Integer :=
Find (List, Name, Get_As (List, Parent, As_Old));
begin
if Index > 0 then
Delete
( List,
Catalogue_Record_Ptr (Get (List.By_Name, Index))
);
end if;
end Delete;
procedure Delete
( List : in out Catalogue;
Name : String;
Parent : Key
) is
Index : constant Integer :=
Find (List, Name, Get_As (List, Parent, As_Old));
begin
if Index > 0 then
Delete
( List,
Catalogue_Record_Ptr (Get (List.By_Name, Index))
);
end if;
end Delete;
procedure Deleted
( Item : in out Catalogue_Record;
Temps : in out Deposit_Container'Class
) is
begin
null;
end Deleted;
procedure Destroyed (Item : in out Catalogue_Record) is
Object : Deposit'Class renames This (Item).all;
begin
if Item.Name_Length = 0 then
--
-- The object is anonymous. It is a candidate for collection
-- when no other object uses it.
--
case Get_Access_Mode (Item.List.Storage.all) is
when Read_Only =>
Raise_Exception
( Use_Error'Identity,
"Nested transaction requires access upgrade"
);
when Read_Write =>
if Has_Dependants
( Item.List.Storage,
Item.External,
True
)
then
if Is_Modified (Object) then
Put (Item.List.Storage.all, Item.External, Object);
Reset_Modified (Object);
end if;
else
Delete (Item.List.Storage.all, Item.External);
end if;
when Fully =>
declare
Mutex : Write_Mutex (Item.List.Storage);
begin
if Has_Dependants
( Item.List.Storage,
Item.External,
True
)
then
if Is_Modified (Object) then
Put
( Item.List.Storage.all,
Item.External,
Object
);
Reset_Modified (Object);
end if;
else
Delete (Item.List.Storage.all, Item.External);
end if;
Commit (Mutex);
end;
end case;
elsif Is_Modified (Object) then
case Get_Access_Mode (Item.List.Storage.all) is
when Read_Only =>
Raise_Exception
( Use_Error'Identity,
"Nested transaction requires access upgrade"
);
when Read_Write =>
Put (Item.List.Storage.all, Item.External, Object);
when Fully =>
declare
Mutex : Write_Mutex (Item.List.Storage);
begin
Put (Item.List.Storage.all, Item.External, Object);
Commit (Mutex);
end;
end case;
Reset_Modified (Object);
end if;
Delete (Item.List.all, Item'Unchecked_Access);
exception
when Use_Error =>
--
-- Nested transaction, this is an idicator that the object is
-- being destroyed upon error recovery which will be followed
-- by the pending transaction roll-back. So the database will
-- not be changed anyway. The object is silently removed from
-- the index an that is.
--
Delete (Item.List.all, Item'Unchecked_Access);
when Error : others =>
Delete (Item.List.all, Item'Unchecked_Access);
On_Error
( Item.List.Storage.all,
"Destroying " & Expanded_Name (Object'Tag),
Error
);
end Destroyed;
procedure Erase (List : in out Catalogue) is
begin
while not Is_Empty (List.By_Key) loop
Delete
( List,
Catalogue_Record_Ptr (Get (List.By_Key, 1))
);
end loop;
end Erase;
procedure Finalize (List : in out Catalogue) is
begin
Erase (List);
exception
when Error : others =>
On_Error
( List.Storage.all,
"Finalizing catalogue",
Error
);
end Finalize;
function Find
( List : Catalogue;
ID : String;
Parent : Catalogue_Record_Ptr
) return Integer is
Item : aliased Catalogue_Record (ID'Length);
begin
Item.Name := ID;
Item.Parent := Parent;
return Find (List.By_Name, Item'Unchecked_Access);
end Find;
function Find (List : Catalogue; ID : Deposit_Ptr) return Integer is
begin
return Find (List.By_Ptr, ID.all'Unchecked_Access);
end Find;
function Find (List : Catalogue; ID : Key) return Integer is
Item : aliased Catalogue_Record (0);
begin
Item.External := ID;
return Find (List.By_Key, Item'Unchecked_Access);
end Find;
function Get (List : Catalogue; Name : String; Parent : Deposit_Ptr)
return Key is
Index : constant Integer :=
Find (List, Name, Get_As (List, Parent, As_Old));
begin
if Index > 0 then
return Get (List.By_Name, Index).External;
end if;
raise End_Error;
end Get;
function Get (List : Catalogue; Name : String; Parent : Key)
return Key is
Index : constant Integer :=
Find (List, Name, Get_As (List, Parent, As_Old));
begin
if Index > 0 then
return Get (List.By_Name, Index).External;
end if;
raise End_Error;
end Get;
function Get (List : Catalogue; Name : String; Parent : Deposit_Ptr)
return Deposit_Ptr is
Index : constant Integer :=
Find (List, Name, Get_As (List, Parent, As_Old));
begin
if Index > 0 then
return This (Get (List.By_Name, Index).all);
end if;
raise End_Error;
end Get;
function Get (List : Catalogue; Name : String; Parent : Key)
return Deposit_Ptr is
Index : constant Integer :=
Find (List, Name, Get_As (List, Parent, As_Old));
begin
if Index > 0 then
return This (Get (List.By_Name, Index).all);
end if;
raise End_Error;
end Get;
function Get (List : Catalogue; ID : Deposit_Ptr) return Key is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
return
Catalogue_Record
( Get (List.By_Ptr, Index).all
) .External;
end if;
raise End_Error;
end Get;
function Get (List : Catalogue; ID : Deposit_Ptr) return String is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
declare
Item : Catalogue_Record renames
Catalogue_Record (Get (List.By_Ptr, Index).all);
begin
if Item.Name'Length > 0 then
return Item.Name;
end if;
end;
end if;
raise End_Error;
end Get;
function Get (List : Catalogue; ID : Key) return String is
Index : constant Integer := Find (List, ID);
begin
if ( Index > 0
and then
Get (List.By_Key, Index).Name'Length > 0
)
then
return Get (List.By_Key, Index).Name;
end if;
raise End_Error;
end Get;
function Get (List : Catalogue; ID : Key) return Deposit_Ptr is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
return This (Get (List.By_Key, Index).all);
end if;
raise End_Error;
end Get;
function Get_As
( List : Catalogue;
ID : Deposit_Ptr;
As : Query_Mode
) return Catalogue_Record_Ptr is
begin
if ID = null then
return null;
end if;
declare
Index : constant Integer := Find (List, ID);
begin
if Index < 0 then
case As is
when As_New =>
Raise_Exception
( Constraint_Error'Identity,
"Parent does not persist"
);
when As_Old =>
Raise_Exception
( Data_Error'Identity,
"Parent does not persist"
);
end case;
end if;
declare
Result : constant Catalogue_Record_Ptr :=
Catalogue_Record_Ptr (Get (List.By_Ptr, Index));
begin
if Result.Name_Length = 0 then
case As is
when As_New =>
Raise_Exception
( Name_Error'Identity,
"Parent is anonymous"
);
when As_Old =>
Raise_Exception
( Data_Error'Identity,
"Parent is anonymous"
);
end case;
end if;
return Result;
end;
end;
end Get_As;
function Get_As
( List : Catalogue;
ID : Key;
As : Query_Mode
) return Catalogue_Record_Ptr is
begin
if ID = Null_Key then
return null;
end if;
declare
Index : constant Integer := Find (List, ID);
begin
if Index < 0 then
case As is
when As_New =>
Raise_Exception
( Constraint_Error'Identity,
"Parent does not persist"
);
when As_Old =>
Raise_Exception
( Data_Error'Identity,
"Parent does not persist"
);
end case;
end if;
declare
Result : constant Catalogue_Record_Ptr :=
Catalogue_Record_Ptr (Get (List.By_Key, Index));
begin
if Result.Name_Length = 0 then
case As is
when As_New =>
Raise_Exception
( Name_Error'Identity,
"Parent is anonymous"
);
when As_Old =>
Raise_Exception
( Data_Error'Identity,
"Parent is anonymous"
);
end case;
end if;
return Result;
end;
end;
end Get_As;
procedure Get_Descendants
( List : Catalogue;
Item : Catalogue_Record_Ptr;
Result : in out Ptr_Map.Set
) is
Child : aliased Catalogue_Record (0);
Index : Integer;
begin
Child.Parent := Item;
Index := Find (List.By_Name, Child'Unchecked_Access);
if Index < 0 then
Index := -Index;
end if;
for Position in Index..Get_Size (List.By_Name) loop
exit when Get (List.By_Name, Position).Parent /= Item;
Add (Result, By_Entity_Ptr (Get (List.By_Name, Position)));
end loop;
end Get_Descendants;
function Get_New_Parent_Key
( List : Catalogue;
Parent : Deposit_Ptr
) return Key is
begin
if Parent = null then
return Null_Key;
else
return Get_As (List, Parent, As_New).External;
end if;
end Get_New_Parent_Key;
function Get_Key (List : Catalogue; ID : Deposit_Ptr) return Key is
begin
if ID = null then
return Null_Key;
else
return Get_As (List, ID, As_Old).External;
end if;
end Get_Key;
function Get_Parent (List : Catalogue; ID : Deposit_Ptr)
return Deposit_Ptr is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
declare
Item : Catalogue_Record renames
Catalogue_Record (Get (List.By_Ptr, Index).all);
begin
if Item.Parent = null then
return null;
else
return This (Item.Parent.all);
end if;
end;
end if;
raise End_Error;
end Get_Parent;
function Get_Parent (List : Catalogue; ID : Deposit_Ptr)
return Key is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
declare
Item : Catalogue_Record renames
Catalogue_Record (Get (List.By_Ptr, Index).all);
begin
if Item.Parent = null then
return Null_Key;
else
return Item.Parent.External;
end if;
end;
end if;
raise End_Error;
end Get_Parent;
function Get_Parent (List : Catalogue; ID : Key)
return Deposit_Ptr is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
declare
Item : Catalogue_Record'Class renames
Catalogue_Record'Class
( Get (List.By_Key, Index).all
);
begin
if Item.Parent = null then
return null;
else
return This (Item.Parent.all);
end if;
end;
end if;
raise End_Error;
end Get_Parent;
function Get_Parent (List : Catalogue; ID : Key) return Key is
Index : constant Integer := Find (List, ID);
begin
if Index > 0 then
declare
Item : Catalogue_Record'Class renames
Catalogue_Record'Class
( Get (List.By_Key, Index).all
);
begin
if Item.Parent = null then
return Null_Key;
else
return Item.Parent.External;
end if;
end;
end if;
raise End_Error;
end Get_Parent;
function Is_Descendant
( List : Catalogue;
Object : Deposit_Ptr;
Parent : Deposit_Ptr
) return Boolean is
begin
if Object = Parent then
return False;
elsif Parent = null then
return Is_In (List, Object);
elsif Object = null then
return False;
end if;
declare
Object_Index : Integer;
Parent_Index : Integer;
That : Catalogue_Record_Ptr;
This : Catalogue_Record_Ptr;
begin
Object_Index := Find (List, Object);
if Object_Index < 0 then
return False;
end if;
Parent_Index := Find (List, Parent);
if Object_Index < 0 then
return False;
end if;
That :=
Catalogue_Record
( Get (List.By_Ptr, Object_Index).all
) 'Unchecked_Access;
This :=
Catalogue_Record
( Get (List.By_Ptr, Parent_Index).all
) 'Unchecked_Access.Parent;
while This /= null loop
if This = That then
return True;
end if;
This := This.Parent;
end loop;
return False;
end;
end Is_Descendant;
function Is_Descendant_Or_Same
( List : Catalogue;
Object : Catalogue_Record_Ptr;
Parent : Catalogue_Record_Ptr
) return Boolean is
begin
if Parent = null or else Object = Parent then
return True;
end if;
if Object = null then
return False;
end if;
declare
This : Catalogue_Record_Ptr := Object.Parent;
begin
while This /= null loop
if This = Parent then
return True;
end if;
This := This.Parent;
end loop;
return False;
end;
end Is_Descendant_Or_Same;
function Is_In (List : Catalogue; ID : Key)
return Boolean is
begin
return Find (List, ID) > 0;
end Is_In;
function Is_In (List : Catalogue; ID : Deposit_Ptr)
return Boolean is
begin
return Find (List, ID) > 0;
end Is_In;
function Is_In (List : Catalogue; ID : String; Parent : Deposit_Ptr)
return Boolean is
begin
return Find (List, ID, Get_As (List, Parent, As_Old)) > 0;
end Is_In;
function Is_In (List : Catalogue; ID : String; Parent : Key)
return Boolean is
begin
return Find (List, ID, Get_As (List, Parent, As_Old)) > 0;
end Is_In;
procedure Notify_Deletion_By_Key
( List : in out Catalogue;
Object : Key
) is
Dependants : Deposit_List;
This : Deposit_Handle;
begin
for Index in 1..Positive'Last loop
-- For each backward link to the object
declare
Link_Key : constant Persistent_Key'Class :=
Get_Dependant (List.Storage, Object, Index);
begin
if not Is_Valid (This) then
-- The object is not resident
This := Get (List.Storage, Object);
end if;
Add (Dependants, Get (List.Storage, Key (Link_Key)));
end;
end loop;
exception
when End_Error =>
if Is_Valid (This) then
--
-- No more backward links. Now List contains all objects
-- dependant on this one. Next we notify them about possible
-- further deletion of the Object.
--
Delete (Ptr (This).all);
Invalidate (This);
end if;
when Error : others =>
On_Error
( List.Storage.all,
"Notifying deletion by key",
Error
);
end Notify_Deletion_By_Key;
procedure Rename
( Store : in out Data_Bank'Class;
List : in out Catalogue;
Old : Catalogue_Record_Ptr;
New_Name : String;
New_Parent : Catalogue_Record_Ptr
) is
procedure Rename_Unchecked
( Old : Catalogue_Record_Ptr;
Name : String;
Parent : Catalogue_Record_Ptr
) is
Link : constant Backward_Link_Ptr :=
new Catalogue_Record (Name'Length);
Item : Catalogue_Record renames Catalogue_Record (Link.all);
begin
Increment_Count (Item);
Item.List := Old.List;
Item.External := Old.External;
Item.Name := Name;
if Parent /= null then
Item.Parent := Parent;
Increment_Count (This (Parent.all).all);
end if;
Attach (Link, This (Old.all));
Delete (List, Old);
Add (List.By_Ptr, Item'Unchecked_Access);
Add (List.By_Key, Item'Unchecked_Access);
if Name'Length = 0 then
declare
Reference : Deposit_Handle;
begin
Deposit_Handles.Set (Reference, This (Link.all));
Delete (Ptr (Reference).all);
end;
else
Add (List.By_Name, Item'Unchecked_Access);
end if;
exception
when others =>
Delete (List, Item'Unchecked_Access);
raise;
end Rename_Unchecked;
begin
if Old.Parent = New_Parent and then Old.Name = New_Name then
return;
end if;
if New_Name'Length > 0 then
--
-- Renaming
--
if Find (List, New_Name, New_Parent) > 0 then
Raise_Exception
( Name_Error'Identity,
( "Object "
& Quote (New_Name)
& " already exists"
) );
end if;
if Is_Descendant_Or_Same (List, New_Parent, Old) then
Raise_Exception
( Name_Error'Identity,
( "Object "
& Quote (New_Name)
& " is renamed to a self-descendant"
) );
end if;
if New_Parent = null then
-- Renamed to root-level
Rename
( Store,
Old.External,
New_Name,
Persistent.Data_Bank.Index.Null_Key
);
else
-- Renamed to have a parent
Rename (Store, Old.External, New_Name, New_Parent.External);
end if;
else
--
-- Recursively unnaming all indexed descendants
--
declare
Descendants : Ptr_Map.Set;
begin
Get_Descendants (List, Old, Descendants);
for Index in 1..Get_Size (Descendants) loop
Rename_Unchecked
( Catalogue_Record_Ptr (Get (Descendants, Index)),
"",
null
);
end loop;
end;
Unname_By_Key (Store, List, Old.External);
end if;
--
-- Renaming / unnaming in the index
--
Rename_Unchecked (Old, New_Name, New_Parent);
end Rename;
procedure Rename
( Store : in out Data_Bank'Class;
List : in out Catalogue;
Old_Name : String;
Old_Parent : Deposit_Ptr;
New_Name : String;
New_Parent : Deposit_Ptr
) is
Where : constant Catalogue_Record_Ptr :=
Get_As (List, Old_Parent, As_Old);
Index : constant Integer := Find (List, Old_Name, Where);
begin
if Index > 0 then
-- The object being renamed is in the index
Rename
( Store,
List,
Catalogue_Record_Ptr (Get (List.By_Name, Index)),
New_Name,
Get_As (List, New_Parent, As_New)
);
elsif Where = null then
-- The object is not in the index and it is a root-level one
declare
Object_Key : constant Key :=
Key
( Find
( Store'Unchecked_Access,
Old_Name,
Persistent.Data_Bank.Index.Null_Key
) );
begin
if Null_Key = Object_Key then
Raise_Exception
( End_Error'Identity,
"Object " & Old_Name & " does not exist"
);
else
Rename
( Store,
Object_Key,
New_Name,
Get_New_Parent_Key (List, New_Parent)
);
end if;
end;
else
-- The object is not in the index
declare
Object_Key : constant Key :=
Key
( Find
( Store'Unchecked_Access,
Old_Name,
Where.External
) );
begin
if Null_Key = Object_Key then
Raise_Exception
( End_Error'Identity,
"Object " & Old_Name & " does not exist"
);
else
Rename
( Store,
Object_Key,
New_Name,
Get_New_Parent_Key (List, New_Parent)
);
end if;
end;
end if;
end Rename;
procedure Rename
( Store : in out Data_Bank'Class;
List : in out Catalogue;
Object : Deposit_Ptr;
New_Name : String;
New_Parent : Deposit_Ptr
) is
Index : constant Integer := Find (List, Object);
begin
if Index <= 0 then
raise Constraint_Error;
end if;
Rename
( Store,
List,
Catalogue_Record_Ptr (Get (List.By_Ptr, Index)),
New_Name,
Get_As (List, New_Parent, As_New)
);
end Rename;
procedure Unname
( Store : in out Data_Bank'Class;
List : in out Catalogue;
Name : String;
Parent : Deposit_Ptr
) is
Where : constant Catalogue_Record_Ptr :=
Get_As (List, Parent, As_Old);
Index : constant Integer := Find (List, Name, Where);
begin
if Index > 0 then
-- The object is in the index
declare
Item : constant Catalogue_Record_Ptr :=
Catalogue_Record_Ptr (Get (List.By_Name, Index));
Object : Deposit_Handle := Ref (This (Item.all));
begin
--
-- Ensure that the object will not be deleted in the course
-- of the notification operation
--
Notify_Deletion_By_Key (List, Item.External);
Rename (Store, List, Item, "", null);
end;
else
-- The object is not in the index
declare
function Parent_Key return Key is
begin
if Where = null then
return Persistent.Data_Bank.Index.Null_Key;
else
return Where.External;
end if;
end Parent_Key;
begin
declare
Object_Key : constant Key :=
Key (Find (Store'Access, Name, Parent_Key));
begin
if Null_Key /= Object_Key then
Notify_Deletion_By_Key (List, Object_Key);
Unname_By_Key (Store, List, Object_Key);
end if;
end;
exception
when End_Error =>
null;
end;
end if;
end Unname;
procedure Unname
( Store : in out Data_Bank'Class;
List : in out Catalogue;
Object : Deposit_Ptr
) is
Index : constant Integer := Find (List, Object);
begin
if Index > 0 then
Rename
( Store,
List,
Catalogue_Record_Ptr (Get (List.By_Ptr, Index)),
"",
null
);
end if;
end Unname;
procedure Unname_By_Key
( Store : in out Data_Bank'Class;
List : in out Catalogue;
ID : Key
) is
function Is_Named (This : Key) return Boolean is
Parent : aliased Key;
begin
declare
Name : String :=
Get_Name (Store'Access, This, Parent'Access);
begin
return True;
end;
exception
when Name_Error | End_Error =>
return False;
end Is_Named;
Unnamed : Key_Array;
Removed : Key_Array;
This : Key := ID;
From : Integer := Integer'First;
To : Integer := Integer'First;
begin
loop
Get_Children (Store, This, Unnamed, To);
--
-- Because the parent object is not in the index none of its
-- successors can be there. For this reason there is no need to
-- check if a child is in the index and handle it any
-- different.
--
if Has_Dependants (Store'Access, This, False) then
--
-- There are other objects using this one
--
Unname (Store, This);
else
--
-- The object is collected. All the objects it refers are
-- checked for collection
--
declare
From : Integer := Integer'First;
To : Integer := Integer'First;
begin
Get_References (Store, This, Removed, To);
Notify_Deletion_By_Key (List, This);
Delete (Store, This);
while From < To loop
This := Key (Get (Removed, From));
From := From + 1;
--
-- Only the object outside the index should be checked
-- for collection. Memory-resident objects will be
-- collected later on destruction.
--
if not
( Is_In (List, This)
or else
Is_Named (This)
or else
Has_Dependants
( Store'Unchecked_Access,
This,
False
) )
then
Get_References (Store, This, Removed, To);
Notify_Deletion_By_Key (List, This);
Delete (Store, This);
end if;
end loop;
end;
end if;
exit when From = To;
This := Key (Get (Unnamed, From));
From := From + 1;
end loop;
end Unname_By_Key;
end Persistent.Data_Bank.Index;
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