0309455b50
2010-01-27 Vasiliy Fofanov <fofanov@adacore.com> * g-regist.adb (For_Every_Key): Fix previous change. 2010-01-27 Thomas Quinot <quinot@adacore.com> * lib-writ.ads: Current version of spec for new N (note) ALI lines 2010-01-27 Yannick Moy <moy@adacore.com> * a-cdlili.adb (Insert): Correct exception message when cursor designates wrong list. From-SVN: r156284
1836 lines
45 KiB
Ada
1836 lines
45 KiB
Ada
------------------------------------------------------------------------------
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-- --
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-- GNAT LIBRARY COMPONENTS --
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-- --
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-- A D A . C O N T A I N E R S . D O U B L Y _ L I N K E D _ L I S T S --
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-- --
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-- B o d y --
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-- --
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-- Copyright (C) 2004-2009, Free Software Foundation, Inc. --
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-- --
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-- GNAT is free software; you can redistribute it and/or modify it under --
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-- terms of the GNU General Public License as published by the Free Soft- --
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-- ware Foundation; either version 3, or (at your option) any later ver- --
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-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
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-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
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-- or FITNESS FOR A PARTICULAR PURPOSE. --
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-- --
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-- As a special exception under Section 7 of GPL version 3, you are granted --
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-- additional permissions described in the GCC Runtime Library Exception, --
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-- version 3.1, as published by the Free Software Foundation. --
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-- --
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-- You should have received a copy of the GNU General Public License and --
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-- a copy of the GCC Runtime Library Exception along with this program; --
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-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
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-- <http://www.gnu.org/licenses/>. --
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-- --
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-- This unit was originally developed by Matthew J Heaney. --
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------------------------------------------------------------------------------
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with System; use type System.Address;
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with Ada.Unchecked_Deallocation;
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package body Ada.Containers.Doubly_Linked_Lists is
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-----------------------
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-- Local Subprograms --
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-----------------------
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procedure Free (X : in out Node_Access);
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procedure Insert_Internal
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(Container : in out List;
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Before : Node_Access;
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New_Node : Node_Access);
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function Vet (Position : Cursor) return Boolean;
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---------
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-- "=" --
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---------
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function "=" (Left, Right : List) return Boolean is
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L : Node_Access := Left.First;
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R : Node_Access := Right.First;
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begin
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if Left'Address = Right'Address then
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return True;
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end if;
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if Left.Length /= Right.Length then
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return False;
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end if;
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for J in 1 .. Left.Length loop
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if L.Element /= R.Element then
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return False;
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end if;
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L := L.Next;
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R := R.Next;
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end loop;
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return True;
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end "=";
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------------
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-- Adjust --
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------------
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procedure Adjust (Container : in out List) is
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Src : Node_Access := Container.First;
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begin
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if Src = null then
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pragma Assert (Container.Last = null);
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pragma Assert (Container.Length = 0);
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pragma Assert (Container.Busy = 0);
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pragma Assert (Container.Lock = 0);
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return;
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end if;
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pragma Assert (Container.First.Prev = null);
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pragma Assert (Container.Last.Next = null);
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pragma Assert (Container.Length > 0);
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Container.First := null;
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Container.Last := null;
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Container.Length := 0;
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Container.Busy := 0;
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Container.Lock := 0;
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Container.First := new Node_Type'(Src.Element, null, null);
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Container.Last := Container.First;
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Container.Length := 1;
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Src := Src.Next;
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while Src /= null loop
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Container.Last.Next := new Node_Type'(Element => Src.Element,
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Prev => Container.Last,
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Next => null);
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Container.Last := Container.Last.Next;
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Container.Length := Container.Length + 1;
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Src := Src.Next;
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end loop;
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end Adjust;
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------------
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-- Append --
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------------
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procedure Append
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(Container : in out List;
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New_Item : Element_Type;
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Count : Count_Type := 1)
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is
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begin
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Insert (Container, No_Element, New_Item, Count);
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end Append;
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-----------
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-- Clear --
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-----------
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procedure Clear (Container : in out List) is
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X : Node_Access;
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begin
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if Container.Length = 0 then
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pragma Assert (Container.First = null);
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pragma Assert (Container.Last = null);
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pragma Assert (Container.Busy = 0);
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pragma Assert (Container.Lock = 0);
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return;
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end if;
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pragma Assert (Container.First.Prev = null);
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pragma Assert (Container.Last.Next = null);
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if Container.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements (list is busy)";
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end if;
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while Container.Length > 1 loop
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X := Container.First;
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pragma Assert (X.Next.Prev = Container.First);
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Container.First := X.Next;
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Container.First.Prev := null;
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Container.Length := Container.Length - 1;
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Free (X);
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end loop;
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X := Container.First;
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pragma Assert (X = Container.Last);
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Container.First := null;
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Container.Last := null;
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Container.Length := 0;
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pragma Warnings (Off);
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Free (X);
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pragma Warnings (On);
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end Clear;
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--------------
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-- Contains --
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--------------
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function Contains
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(Container : List;
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Item : Element_Type) return Boolean
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is
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begin
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return Find (Container, Item) /= No_Element;
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end Contains;
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------------
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-- Delete --
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------------
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procedure Delete
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(Container : in out List;
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Position : in out Cursor;
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Count : Count_Type := 1)
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is
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X : Node_Access;
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begin
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if Position.Node = null then
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raise Constraint_Error with
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"Position cursor has no element";
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end if;
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if Position.Container /= Container'Unrestricted_Access then
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raise Program_Error with
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"Position cursor designates wrong container";
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end if;
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pragma Assert (Vet (Position), "bad cursor in Delete");
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if Position.Node = Container.First then
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Delete_First (Container, Count);
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Position := No_Element; -- Post-York behavior
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return;
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end if;
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if Count = 0 then
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Position := No_Element; -- Post-York behavior
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return;
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end if;
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if Container.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements (list is busy)";
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end if;
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for Index in 1 .. Count loop
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X := Position.Node;
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Container.Length := Container.Length - 1;
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if X = Container.Last then
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Position := No_Element;
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Container.Last := X.Prev;
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Container.Last.Next := null;
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Free (X);
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return;
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end if;
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Position.Node := X.Next;
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X.Next.Prev := X.Prev;
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X.Prev.Next := X.Next;
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Free (X);
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end loop;
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Position := No_Element; -- Post-York behavior
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end Delete;
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------------------
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-- Delete_First --
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------------------
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procedure Delete_First
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(Container : in out List;
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Count : Count_Type := 1)
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is
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X : Node_Access;
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begin
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if Count >= Container.Length then
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Clear (Container);
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return;
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end if;
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if Count = 0 then
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return;
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end if;
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if Container.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements (list is busy)";
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end if;
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for I in 1 .. Count loop
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X := Container.First;
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pragma Assert (X.Next.Prev = Container.First);
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Container.First := X.Next;
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Container.First.Prev := null;
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Container.Length := Container.Length - 1;
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Free (X);
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end loop;
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end Delete_First;
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-----------------
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-- Delete_Last --
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-----------------
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procedure Delete_Last
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(Container : in out List;
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Count : Count_Type := 1)
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is
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X : Node_Access;
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begin
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if Count >= Container.Length then
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Clear (Container);
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return;
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end if;
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if Count = 0 then
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return;
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end if;
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if Container.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements (list is busy)";
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end if;
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for I in 1 .. Count loop
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X := Container.Last;
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pragma Assert (X.Prev.Next = Container.Last);
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Container.Last := X.Prev;
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Container.Last.Next := null;
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Container.Length := Container.Length - 1;
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Free (X);
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end loop;
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end Delete_Last;
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-------------
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-- Element --
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-------------
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function Element (Position : Cursor) return Element_Type is
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begin
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if Position.Node = null then
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raise Constraint_Error with
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"Position cursor has no element";
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end if;
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pragma Assert (Vet (Position), "bad cursor in Element");
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return Position.Node.Element;
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end Element;
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----------
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-- Find --
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----------
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function Find
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(Container : List;
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Item : Element_Type;
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Position : Cursor := No_Element) return Cursor
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is
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Node : Node_Access := Position.Node;
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begin
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if Node = null then
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Node := Container.First;
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else
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if Position.Container /= Container'Unrestricted_Access then
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raise Program_Error with
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"Position cursor designates wrong container";
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end if;
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pragma Assert (Vet (Position), "bad cursor in Find");
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end if;
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while Node /= null loop
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if Node.Element = Item then
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return Cursor'(Container'Unchecked_Access, Node);
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end if;
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Node := Node.Next;
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end loop;
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return No_Element;
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end Find;
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-----------
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-- First --
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-----------
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function First (Container : List) return Cursor is
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begin
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if Container.First = null then
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return No_Element;
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end if;
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return Cursor'(Container'Unchecked_Access, Container.First);
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end First;
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-------------------
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-- First_Element --
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-------------------
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function First_Element (Container : List) return Element_Type is
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begin
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if Container.First = null then
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raise Constraint_Error with "list is empty";
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end if;
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return Container.First.Element;
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end First_Element;
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----------
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-- Free --
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----------
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procedure Free (X : in out Node_Access) is
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procedure Deallocate is
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new Ada.Unchecked_Deallocation (Node_Type, Node_Access);
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begin
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X.Prev := X;
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X.Next := X;
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Deallocate (X);
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end Free;
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---------------------
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-- Generic_Sorting --
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---------------------
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package body Generic_Sorting is
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---------------
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-- Is_Sorted --
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---------------
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function Is_Sorted (Container : List) return Boolean is
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Node : Node_Access := Container.First;
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begin
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for I in 2 .. Container.Length loop
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if Node.Next.Element < Node.Element then
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return False;
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end if;
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Node := Node.Next;
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end loop;
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return True;
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end Is_Sorted;
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-----------
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-- Merge --
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-----------
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procedure Merge
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(Target : in out List;
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Source : in out List)
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is
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LI, RI : Cursor;
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begin
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if Target'Address = Source'Address then
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return;
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end if;
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if Target.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements of Target (list is busy)";
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end if;
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if Source.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements of Source (list is busy)";
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end if;
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LI := First (Target);
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RI := First (Source);
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while RI.Node /= null loop
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pragma Assert (RI.Node.Next = null
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or else not (RI.Node.Next.Element <
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RI.Node.Element));
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if LI.Node = null then
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Splice (Target, No_Element, Source);
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return;
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end if;
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pragma Assert (LI.Node.Next = null
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or else not (LI.Node.Next.Element <
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LI.Node.Element));
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if RI.Node.Element < LI.Node.Element then
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declare
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RJ : Cursor := RI;
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pragma Warnings (Off, RJ);
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begin
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RI.Node := RI.Node.Next;
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Splice (Target, LI, Source, RJ);
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end;
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else
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LI.Node := LI.Node.Next;
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end if;
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end loop;
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end Merge;
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----------
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-- Sort --
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----------
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procedure Sort (Container : in out List) is
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procedure Partition (Pivot : Node_Access; Back : Node_Access);
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procedure Sort (Front, Back : Node_Access);
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---------------
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-- Partition --
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---------------
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procedure Partition (Pivot : Node_Access; Back : Node_Access) is
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Node : Node_Access := Pivot.Next;
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begin
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while Node /= Back loop
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if Node.Element < Pivot.Element then
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declare
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Prev : constant Node_Access := Node.Prev;
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Next : constant Node_Access := Node.Next;
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begin
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Prev.Next := Next;
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if Next = null then
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Container.Last := Prev;
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else
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Next.Prev := Prev;
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end if;
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Node.Next := Pivot;
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Node.Prev := Pivot.Prev;
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Pivot.Prev := Node;
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if Node.Prev = null then
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Container.First := Node;
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else
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Node.Prev.Next := Node;
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end if;
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Node := Next;
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end;
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else
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Node := Node.Next;
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end if;
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end loop;
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end Partition;
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----------
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-- Sort --
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----------
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procedure Sort (Front, Back : Node_Access) is
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Pivot : constant Node_Access :=
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(if Front = null then Container.First else Front.Next);
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begin
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if Pivot /= Back then
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Partition (Pivot, Back);
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Sort (Front, Pivot);
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Sort (Pivot, Back);
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end if;
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end Sort;
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|
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-- Start of processing for Sort
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begin
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if Container.Length <= 1 then
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return;
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end if;
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pragma Assert (Container.First.Prev = null);
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pragma Assert (Container.Last.Next = null);
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if Container.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements (list is busy)";
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end if;
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Sort (Front => null, Back => null);
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pragma Assert (Container.First.Prev = null);
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pragma Assert (Container.Last.Next = null);
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end Sort;
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end Generic_Sorting;
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|
|
-----------------
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-- Has_Element --
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-----------------
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|
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function Has_Element (Position : Cursor) return Boolean is
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begin
|
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pragma Assert (Vet (Position), "bad cursor in Has_Element");
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return Position.Node /= null;
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end Has_Element;
|
|
|
|
------------
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|
-- Insert --
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|
------------
|
|
|
|
procedure Insert
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(Container : in out List;
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Before : Cursor;
|
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New_Item : Element_Type;
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Position : out Cursor;
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Count : Count_Type := 1)
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is
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New_Node : Node_Access;
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begin
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if Before.Container /= null then
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if Before.Container /= Container'Unrestricted_Access then
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raise Program_Error with
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"Before cursor designates wrong list";
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end if;
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pragma Assert (Vet (Before), "bad cursor in Insert");
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end if;
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if Count = 0 then
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Position := Before;
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return;
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end if;
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|
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if Container.Length > Count_Type'Last - Count then
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raise Constraint_Error with "new length exceeds maximum";
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end if;
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|
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if Container.Busy > 0 then
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raise Program_Error with
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"attempt to tamper with elements (list is busy)";
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end if;
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|
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New_Node := new Node_Type'(New_Item, null, null);
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Insert_Internal (Container, Before.Node, New_Node);
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Position := Cursor'(Container'Unchecked_Access, New_Node);
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|
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for J in Count_Type'(2) .. Count loop
|
|
New_Node := new Node_Type'(New_Item, null, null);
|
|
Insert_Internal (Container, Before.Node, New_Node);
|
|
end loop;
|
|
end Insert;
|
|
|
|
procedure Insert
|
|
(Container : in out List;
|
|
Before : Cursor;
|
|
New_Item : Element_Type;
|
|
Count : Count_Type := 1)
|
|
is
|
|
Position : Cursor;
|
|
pragma Unreferenced (Position);
|
|
begin
|
|
Insert (Container, Before, New_Item, Position, Count);
|
|
end Insert;
|
|
|
|
procedure Insert
|
|
(Container : in out List;
|
|
Before : Cursor;
|
|
Position : out Cursor;
|
|
Count : Count_Type := 1)
|
|
is
|
|
New_Node : Node_Access;
|
|
|
|
begin
|
|
if Before.Container /= null then
|
|
if Before.Container /= Container'Unrestricted_Access then
|
|
raise Program_Error with
|
|
"Before cursor designates wrong list";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Before), "bad cursor in Insert");
|
|
end if;
|
|
|
|
if Count = 0 then
|
|
Position := Before;
|
|
return;
|
|
end if;
|
|
|
|
if Container.Length > Count_Type'Last - Count then
|
|
raise Constraint_Error with "new length exceeds maximum";
|
|
end if;
|
|
|
|
if Container.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements (list is busy)";
|
|
end if;
|
|
|
|
New_Node := new Node_Type;
|
|
Insert_Internal (Container, Before.Node, New_Node);
|
|
|
|
Position := Cursor'(Container'Unchecked_Access, New_Node);
|
|
|
|
for J in Count_Type'(2) .. Count loop
|
|
New_Node := new Node_Type;
|
|
Insert_Internal (Container, Before.Node, New_Node);
|
|
end loop;
|
|
end Insert;
|
|
|
|
---------------------
|
|
-- Insert_Internal --
|
|
---------------------
|
|
|
|
procedure Insert_Internal
|
|
(Container : in out List;
|
|
Before : Node_Access;
|
|
New_Node : Node_Access)
|
|
is
|
|
begin
|
|
if Container.Length = 0 then
|
|
pragma Assert (Before = null);
|
|
pragma Assert (Container.First = null);
|
|
pragma Assert (Container.Last = null);
|
|
|
|
Container.First := New_Node;
|
|
Container.Last := New_Node;
|
|
|
|
elsif Before = null then
|
|
pragma Assert (Container.Last.Next = null);
|
|
|
|
Container.Last.Next := New_Node;
|
|
New_Node.Prev := Container.Last;
|
|
|
|
Container.Last := New_Node;
|
|
|
|
elsif Before = Container.First then
|
|
pragma Assert (Container.First.Prev = null);
|
|
|
|
Container.First.Prev := New_Node;
|
|
New_Node.Next := Container.First;
|
|
|
|
Container.First := New_Node;
|
|
|
|
else
|
|
pragma Assert (Container.First.Prev = null);
|
|
pragma Assert (Container.Last.Next = null);
|
|
|
|
New_Node.Next := Before;
|
|
New_Node.Prev := Before.Prev;
|
|
|
|
Before.Prev.Next := New_Node;
|
|
Before.Prev := New_Node;
|
|
end if;
|
|
|
|
Container.Length := Container.Length + 1;
|
|
end Insert_Internal;
|
|
|
|
--------------
|
|
-- Is_Empty --
|
|
--------------
|
|
|
|
function Is_Empty (Container : List) return Boolean is
|
|
begin
|
|
return Container.Length = 0;
|
|
end Is_Empty;
|
|
|
|
-------------
|
|
-- Iterate --
|
|
-------------
|
|
|
|
procedure Iterate
|
|
(Container : List;
|
|
Process : not null access procedure (Position : Cursor))
|
|
is
|
|
C : List renames Container'Unrestricted_Access.all;
|
|
B : Natural renames C.Busy;
|
|
|
|
Node : Node_Access := Container.First;
|
|
|
|
begin
|
|
B := B + 1;
|
|
|
|
begin
|
|
while Node /= null loop
|
|
Process (Cursor'(Container'Unchecked_Access, Node));
|
|
Node := Node.Next;
|
|
end loop;
|
|
exception
|
|
when others =>
|
|
B := B - 1;
|
|
raise;
|
|
end;
|
|
|
|
B := B - 1;
|
|
end Iterate;
|
|
|
|
----------
|
|
-- Last --
|
|
----------
|
|
|
|
function Last (Container : List) return Cursor is
|
|
begin
|
|
if Container.Last = null then
|
|
return No_Element;
|
|
end if;
|
|
|
|
return Cursor'(Container'Unchecked_Access, Container.Last);
|
|
end Last;
|
|
|
|
------------------
|
|
-- Last_Element --
|
|
------------------
|
|
|
|
function Last_Element (Container : List) return Element_Type is
|
|
begin
|
|
if Container.Last = null then
|
|
raise Constraint_Error with "list is empty";
|
|
end if;
|
|
|
|
return Container.Last.Element;
|
|
end Last_Element;
|
|
|
|
------------
|
|
-- Length --
|
|
------------
|
|
|
|
function Length (Container : List) return Count_Type is
|
|
begin
|
|
return Container.Length;
|
|
end Length;
|
|
|
|
----------
|
|
-- Move --
|
|
----------
|
|
|
|
procedure Move
|
|
(Target : in out List;
|
|
Source : in out List)
|
|
is
|
|
begin
|
|
if Target'Address = Source'Address then
|
|
return;
|
|
end if;
|
|
|
|
if Source.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements of Source (list is busy)";
|
|
end if;
|
|
|
|
Clear (Target);
|
|
|
|
Target.First := Source.First;
|
|
Source.First := null;
|
|
|
|
Target.Last := Source.Last;
|
|
Source.Last := null;
|
|
|
|
Target.Length := Source.Length;
|
|
Source.Length := 0;
|
|
end Move;
|
|
|
|
----------
|
|
-- Next --
|
|
----------
|
|
|
|
procedure Next (Position : in out Cursor) is
|
|
begin
|
|
Position := Next (Position);
|
|
end Next;
|
|
|
|
function Next (Position : Cursor) return Cursor is
|
|
begin
|
|
if Position.Node = null then
|
|
return No_Element;
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad cursor in Next");
|
|
|
|
declare
|
|
Next_Node : constant Node_Access := Position.Node.Next;
|
|
begin
|
|
if Next_Node = null then
|
|
return No_Element;
|
|
end if;
|
|
|
|
return Cursor'(Position.Container, Next_Node);
|
|
end;
|
|
end Next;
|
|
|
|
-------------
|
|
-- Prepend --
|
|
-------------
|
|
|
|
procedure Prepend
|
|
(Container : in out List;
|
|
New_Item : Element_Type;
|
|
Count : Count_Type := 1)
|
|
is
|
|
begin
|
|
Insert (Container, First (Container), New_Item, Count);
|
|
end Prepend;
|
|
|
|
--------------
|
|
-- Previous --
|
|
--------------
|
|
|
|
procedure Previous (Position : in out Cursor) is
|
|
begin
|
|
Position := Previous (Position);
|
|
end Previous;
|
|
|
|
function Previous (Position : Cursor) return Cursor is
|
|
begin
|
|
if Position.Node = null then
|
|
return No_Element;
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad cursor in Previous");
|
|
|
|
declare
|
|
Prev_Node : constant Node_Access := Position.Node.Prev;
|
|
begin
|
|
if Prev_Node = null then
|
|
return No_Element;
|
|
end if;
|
|
|
|
return Cursor'(Position.Container, Prev_Node);
|
|
end;
|
|
end Previous;
|
|
|
|
-------------------
|
|
-- Query_Element --
|
|
-------------------
|
|
|
|
procedure Query_Element
|
|
(Position : Cursor;
|
|
Process : not null access procedure (Element : Element_Type))
|
|
is
|
|
begin
|
|
if Position.Node = null then
|
|
raise Constraint_Error with
|
|
"Position cursor has no element";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad cursor in Query_Element");
|
|
|
|
declare
|
|
C : List renames Position.Container.all'Unrestricted_Access.all;
|
|
B : Natural renames C.Busy;
|
|
L : Natural renames C.Lock;
|
|
|
|
begin
|
|
B := B + 1;
|
|
L := L + 1;
|
|
|
|
begin
|
|
Process (Position.Node.Element);
|
|
exception
|
|
when others =>
|
|
L := L - 1;
|
|
B := B - 1;
|
|
raise;
|
|
end;
|
|
|
|
L := L - 1;
|
|
B := B - 1;
|
|
end;
|
|
end Query_Element;
|
|
|
|
----------
|
|
-- Read --
|
|
----------
|
|
|
|
procedure Read
|
|
(Stream : not null access Root_Stream_Type'Class;
|
|
Item : out List)
|
|
is
|
|
N : Count_Type'Base;
|
|
X : Node_Access;
|
|
|
|
begin
|
|
Clear (Item);
|
|
Count_Type'Base'Read (Stream, N);
|
|
|
|
if N = 0 then
|
|
return;
|
|
end if;
|
|
|
|
X := new Node_Type;
|
|
|
|
begin
|
|
Element_Type'Read (Stream, X.Element);
|
|
exception
|
|
when others =>
|
|
Free (X);
|
|
raise;
|
|
end;
|
|
|
|
Item.First := X;
|
|
Item.Last := X;
|
|
|
|
loop
|
|
Item.Length := Item.Length + 1;
|
|
exit when Item.Length = N;
|
|
|
|
X := new Node_Type;
|
|
|
|
begin
|
|
Element_Type'Read (Stream, X.Element);
|
|
exception
|
|
when others =>
|
|
Free (X);
|
|
raise;
|
|
end;
|
|
|
|
X.Prev := Item.Last;
|
|
Item.Last.Next := X;
|
|
Item.Last := X;
|
|
end loop;
|
|
end Read;
|
|
|
|
procedure Read
|
|
(Stream : not null access Root_Stream_Type'Class;
|
|
Item : out Cursor)
|
|
is
|
|
begin
|
|
raise Program_Error with "attempt to stream list cursor";
|
|
end Read;
|
|
|
|
---------------------
|
|
-- Replace_Element --
|
|
---------------------
|
|
|
|
procedure Replace_Element
|
|
(Container : in out List;
|
|
Position : Cursor;
|
|
New_Item : Element_Type)
|
|
is
|
|
begin
|
|
if Position.Container = null then
|
|
raise Constraint_Error with "Position cursor has no element";
|
|
end if;
|
|
|
|
if Position.Container /= Container'Unchecked_Access then
|
|
raise Program_Error with
|
|
"Position cursor designates wrong container";
|
|
end if;
|
|
|
|
if Container.Lock > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with cursors (list is locked)";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad cursor in Replace_Element");
|
|
|
|
Position.Node.Element := New_Item;
|
|
end Replace_Element;
|
|
|
|
----------------------
|
|
-- Reverse_Elements --
|
|
----------------------
|
|
|
|
procedure Reverse_Elements (Container : in out List) is
|
|
I : Node_Access := Container.First;
|
|
J : Node_Access := Container.Last;
|
|
|
|
procedure Swap (L, R : Node_Access);
|
|
|
|
----------
|
|
-- Swap --
|
|
----------
|
|
|
|
procedure Swap (L, R : Node_Access) is
|
|
LN : constant Node_Access := L.Next;
|
|
LP : constant Node_Access := L.Prev;
|
|
|
|
RN : constant Node_Access := R.Next;
|
|
RP : constant Node_Access := R.Prev;
|
|
|
|
begin
|
|
if LP /= null then
|
|
LP.Next := R;
|
|
end if;
|
|
|
|
if RN /= null then
|
|
RN.Prev := L;
|
|
end if;
|
|
|
|
L.Next := RN;
|
|
R.Prev := LP;
|
|
|
|
if LN = R then
|
|
pragma Assert (RP = L);
|
|
|
|
L.Prev := R;
|
|
R.Next := L;
|
|
|
|
else
|
|
L.Prev := RP;
|
|
RP.Next := L;
|
|
|
|
R.Next := LN;
|
|
LN.Prev := R;
|
|
end if;
|
|
end Swap;
|
|
|
|
-- Start of processing for Reverse_Elements
|
|
|
|
begin
|
|
if Container.Length <= 1 then
|
|
return;
|
|
end if;
|
|
|
|
pragma Assert (Container.First.Prev = null);
|
|
pragma Assert (Container.Last.Next = null);
|
|
|
|
if Container.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements (list is busy)";
|
|
end if;
|
|
|
|
Container.First := J;
|
|
Container.Last := I;
|
|
loop
|
|
Swap (L => I, R => J);
|
|
|
|
J := J.Next;
|
|
exit when I = J;
|
|
|
|
I := I.Prev;
|
|
exit when I = J;
|
|
|
|
Swap (L => J, R => I);
|
|
|
|
I := I.Next;
|
|
exit when I = J;
|
|
|
|
J := J.Prev;
|
|
exit when I = J;
|
|
end loop;
|
|
|
|
pragma Assert (Container.First.Prev = null);
|
|
pragma Assert (Container.Last.Next = null);
|
|
end Reverse_Elements;
|
|
|
|
------------------
|
|
-- Reverse_Find --
|
|
------------------
|
|
|
|
function Reverse_Find
|
|
(Container : List;
|
|
Item : Element_Type;
|
|
Position : Cursor := No_Element) return Cursor
|
|
is
|
|
Node : Node_Access := Position.Node;
|
|
|
|
begin
|
|
if Node = null then
|
|
Node := Container.Last;
|
|
|
|
else
|
|
if Position.Container /= Container'Unrestricted_Access then
|
|
raise Program_Error with
|
|
"Position cursor designates wrong container";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad cursor in Reverse_Find");
|
|
end if;
|
|
|
|
while Node /= null loop
|
|
if Node.Element = Item then
|
|
return Cursor'(Container'Unchecked_Access, Node);
|
|
end if;
|
|
|
|
Node := Node.Prev;
|
|
end loop;
|
|
|
|
return No_Element;
|
|
end Reverse_Find;
|
|
|
|
---------------------
|
|
-- Reverse_Iterate --
|
|
---------------------
|
|
|
|
procedure Reverse_Iterate
|
|
(Container : List;
|
|
Process : not null access procedure (Position : Cursor))
|
|
is
|
|
C : List renames Container'Unrestricted_Access.all;
|
|
B : Natural renames C.Busy;
|
|
|
|
Node : Node_Access := Container.Last;
|
|
|
|
begin
|
|
B := B + 1;
|
|
|
|
begin
|
|
while Node /= null loop
|
|
Process (Cursor'(Container'Unchecked_Access, Node));
|
|
Node := Node.Prev;
|
|
end loop;
|
|
|
|
exception
|
|
when others =>
|
|
B := B - 1;
|
|
raise;
|
|
end;
|
|
|
|
B := B - 1;
|
|
end Reverse_Iterate;
|
|
|
|
------------
|
|
-- Splice --
|
|
------------
|
|
|
|
procedure Splice
|
|
(Target : in out List;
|
|
Before : Cursor;
|
|
Source : in out List)
|
|
is
|
|
begin
|
|
if Before.Container /= null then
|
|
if Before.Container /= Target'Unrestricted_Access then
|
|
raise Program_Error with
|
|
"Before cursor designates wrong container";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Before), "bad cursor in Splice");
|
|
end if;
|
|
|
|
if Target'Address = Source'Address
|
|
or else Source.Length = 0
|
|
then
|
|
return;
|
|
end if;
|
|
|
|
pragma Assert (Source.First.Prev = null);
|
|
pragma Assert (Source.Last.Next = null);
|
|
|
|
if Target.Length > Count_Type'Last - Source.Length then
|
|
raise Constraint_Error with "new length exceeds maximum";
|
|
end if;
|
|
|
|
if Target.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements of Target (list is busy)";
|
|
end if;
|
|
|
|
if Source.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements of Source (list is busy)";
|
|
end if;
|
|
|
|
if Target.Length = 0 then
|
|
pragma Assert (Target.First = null);
|
|
pragma Assert (Target.Last = null);
|
|
pragma Assert (Before = No_Element);
|
|
|
|
Target.First := Source.First;
|
|
Target.Last := Source.Last;
|
|
|
|
elsif Before.Node = null then
|
|
pragma Assert (Target.Last.Next = null);
|
|
|
|
Target.Last.Next := Source.First;
|
|
Source.First.Prev := Target.Last;
|
|
|
|
Target.Last := Source.Last;
|
|
|
|
elsif Before.Node = Target.First then
|
|
pragma Assert (Target.First.Prev = null);
|
|
|
|
Source.Last.Next := Target.First;
|
|
Target.First.Prev := Source.Last;
|
|
|
|
Target.First := Source.First;
|
|
|
|
else
|
|
pragma Assert (Target.Length >= 2);
|
|
|
|
Before.Node.Prev.Next := Source.First;
|
|
Source.First.Prev := Before.Node.Prev;
|
|
|
|
Before.Node.Prev := Source.Last;
|
|
Source.Last.Next := Before.Node;
|
|
end if;
|
|
|
|
Source.First := null;
|
|
Source.Last := null;
|
|
|
|
Target.Length := Target.Length + Source.Length;
|
|
Source.Length := 0;
|
|
end Splice;
|
|
|
|
procedure Splice
|
|
(Container : in out List;
|
|
Before : Cursor;
|
|
Position : Cursor)
|
|
is
|
|
begin
|
|
if Before.Container /= null then
|
|
if Before.Container /= Container'Unchecked_Access then
|
|
raise Program_Error with
|
|
"Before cursor designates wrong container";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Before), "bad Before cursor in Splice");
|
|
end if;
|
|
|
|
if Position.Node = null then
|
|
raise Constraint_Error with "Position cursor has no element";
|
|
end if;
|
|
|
|
if Position.Container /= Container'Unrestricted_Access then
|
|
raise Program_Error with
|
|
"Position cursor designates wrong container";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad Position cursor in Splice");
|
|
|
|
if Position.Node = Before.Node
|
|
or else Position.Node.Next = Before.Node
|
|
then
|
|
return;
|
|
end if;
|
|
|
|
pragma Assert (Container.Length >= 2);
|
|
|
|
if Container.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements (list is busy)";
|
|
end if;
|
|
|
|
if Before.Node = null then
|
|
pragma Assert (Position.Node /= Container.Last);
|
|
|
|
if Position.Node = Container.First then
|
|
Container.First := Position.Node.Next;
|
|
Container.First.Prev := null;
|
|
else
|
|
Position.Node.Prev.Next := Position.Node.Next;
|
|
Position.Node.Next.Prev := Position.Node.Prev;
|
|
end if;
|
|
|
|
Container.Last.Next := Position.Node;
|
|
Position.Node.Prev := Container.Last;
|
|
|
|
Container.Last := Position.Node;
|
|
Container.Last.Next := null;
|
|
|
|
return;
|
|
end if;
|
|
|
|
if Before.Node = Container.First then
|
|
pragma Assert (Position.Node /= Container.First);
|
|
|
|
if Position.Node = Container.Last then
|
|
Container.Last := Position.Node.Prev;
|
|
Container.Last.Next := null;
|
|
else
|
|
Position.Node.Prev.Next := Position.Node.Next;
|
|
Position.Node.Next.Prev := Position.Node.Prev;
|
|
end if;
|
|
|
|
Container.First.Prev := Position.Node;
|
|
Position.Node.Next := Container.First;
|
|
|
|
Container.First := Position.Node;
|
|
Container.First.Prev := null;
|
|
|
|
return;
|
|
end if;
|
|
|
|
if Position.Node = Container.First then
|
|
Container.First := Position.Node.Next;
|
|
Container.First.Prev := null;
|
|
|
|
elsif Position.Node = Container.Last then
|
|
Container.Last := Position.Node.Prev;
|
|
Container.Last.Next := null;
|
|
|
|
else
|
|
Position.Node.Prev.Next := Position.Node.Next;
|
|
Position.Node.Next.Prev := Position.Node.Prev;
|
|
end if;
|
|
|
|
Before.Node.Prev.Next := Position.Node;
|
|
Position.Node.Prev := Before.Node.Prev;
|
|
|
|
Before.Node.Prev := Position.Node;
|
|
Position.Node.Next := Before.Node;
|
|
|
|
pragma Assert (Container.First.Prev = null);
|
|
pragma Assert (Container.Last.Next = null);
|
|
end Splice;
|
|
|
|
procedure Splice
|
|
(Target : in out List;
|
|
Before : Cursor;
|
|
Source : in out List;
|
|
Position : in out Cursor)
|
|
is
|
|
begin
|
|
if Target'Address = Source'Address then
|
|
Splice (Target, Before, Position);
|
|
return;
|
|
end if;
|
|
|
|
if Before.Container /= null then
|
|
if Before.Container /= Target'Unrestricted_Access then
|
|
raise Program_Error with
|
|
"Before cursor designates wrong container";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Before), "bad Before cursor in Splice");
|
|
end if;
|
|
|
|
if Position.Node = null then
|
|
raise Constraint_Error with "Position cursor has no element";
|
|
end if;
|
|
|
|
if Position.Container /= Source'Unrestricted_Access then
|
|
raise Program_Error with
|
|
"Position cursor designates wrong container";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad Position cursor in Splice");
|
|
|
|
if Target.Length = Count_Type'Last then
|
|
raise Constraint_Error with "Target is full";
|
|
end if;
|
|
|
|
if Target.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements of Target (list is busy)";
|
|
end if;
|
|
|
|
if Source.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements of Source (list is busy)";
|
|
end if;
|
|
|
|
if Position.Node = Source.First then
|
|
Source.First := Position.Node.Next;
|
|
|
|
if Position.Node = Source.Last then
|
|
pragma Assert (Source.First = null);
|
|
pragma Assert (Source.Length = 1);
|
|
Source.Last := null;
|
|
|
|
else
|
|
Source.First.Prev := null;
|
|
end if;
|
|
|
|
elsif Position.Node = Source.Last then
|
|
pragma Assert (Source.Length >= 2);
|
|
Source.Last := Position.Node.Prev;
|
|
Source.Last.Next := null;
|
|
|
|
else
|
|
pragma Assert (Source.Length >= 3);
|
|
Position.Node.Prev.Next := Position.Node.Next;
|
|
Position.Node.Next.Prev := Position.Node.Prev;
|
|
end if;
|
|
|
|
if Target.Length = 0 then
|
|
pragma Assert (Target.First = null);
|
|
pragma Assert (Target.Last = null);
|
|
pragma Assert (Before = No_Element);
|
|
|
|
Target.First := Position.Node;
|
|
Target.Last := Position.Node;
|
|
|
|
Target.First.Prev := null;
|
|
Target.Last.Next := null;
|
|
|
|
elsif Before.Node = null then
|
|
pragma Assert (Target.Last.Next = null);
|
|
Target.Last.Next := Position.Node;
|
|
Position.Node.Prev := Target.Last;
|
|
|
|
Target.Last := Position.Node;
|
|
Target.Last.Next := null;
|
|
|
|
elsif Before.Node = Target.First then
|
|
pragma Assert (Target.First.Prev = null);
|
|
Target.First.Prev := Position.Node;
|
|
Position.Node.Next := Target.First;
|
|
|
|
Target.First := Position.Node;
|
|
Target.First.Prev := null;
|
|
|
|
else
|
|
pragma Assert (Target.Length >= 2);
|
|
Before.Node.Prev.Next := Position.Node;
|
|
Position.Node.Prev := Before.Node.Prev;
|
|
|
|
Before.Node.Prev := Position.Node;
|
|
Position.Node.Next := Before.Node;
|
|
end if;
|
|
|
|
Target.Length := Target.Length + 1;
|
|
Source.Length := Source.Length - 1;
|
|
|
|
Position.Container := Target'Unchecked_Access;
|
|
end Splice;
|
|
|
|
----------
|
|
-- Swap --
|
|
----------
|
|
|
|
procedure Swap
|
|
(Container : in out List;
|
|
I, J : Cursor)
|
|
is
|
|
begin
|
|
if I.Node = null then
|
|
raise Constraint_Error with "I cursor has no element";
|
|
end if;
|
|
|
|
if J.Node = null then
|
|
raise Constraint_Error with "J cursor has no element";
|
|
end if;
|
|
|
|
if I.Container /= Container'Unchecked_Access then
|
|
raise Program_Error with "I cursor designates wrong container";
|
|
end if;
|
|
|
|
if J.Container /= Container'Unchecked_Access then
|
|
raise Program_Error with "J cursor designates wrong container";
|
|
end if;
|
|
|
|
if I.Node = J.Node then
|
|
return;
|
|
end if;
|
|
|
|
if Container.Lock > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with cursors (list is locked)";
|
|
end if;
|
|
|
|
pragma Assert (Vet (I), "bad I cursor in Swap");
|
|
pragma Assert (Vet (J), "bad J cursor in Swap");
|
|
|
|
declare
|
|
EI : Element_Type renames I.Node.Element;
|
|
EJ : Element_Type renames J.Node.Element;
|
|
|
|
EI_Copy : constant Element_Type := EI;
|
|
|
|
begin
|
|
EI := EJ;
|
|
EJ := EI_Copy;
|
|
end;
|
|
end Swap;
|
|
|
|
----------------
|
|
-- Swap_Links --
|
|
----------------
|
|
|
|
procedure Swap_Links
|
|
(Container : in out List;
|
|
I, J : Cursor)
|
|
is
|
|
begin
|
|
if I.Node = null then
|
|
raise Constraint_Error with "I cursor has no element";
|
|
end if;
|
|
|
|
if J.Node = null then
|
|
raise Constraint_Error with "J cursor has no element";
|
|
end if;
|
|
|
|
if I.Container /= Container'Unrestricted_Access then
|
|
raise Program_Error with "I cursor designates wrong container";
|
|
end if;
|
|
|
|
if J.Container /= Container'Unrestricted_Access then
|
|
raise Program_Error with "J cursor designates wrong container";
|
|
end if;
|
|
|
|
if I.Node = J.Node then
|
|
return;
|
|
end if;
|
|
|
|
if Container.Busy > 0 then
|
|
raise Program_Error with
|
|
"attempt to tamper with elements (list is busy)";
|
|
end if;
|
|
|
|
pragma Assert (Vet (I), "bad I cursor in Swap_Links");
|
|
pragma Assert (Vet (J), "bad J cursor in Swap_Links");
|
|
|
|
declare
|
|
I_Next : constant Cursor := Next (I);
|
|
|
|
begin
|
|
if I_Next = J then
|
|
Splice (Container, Before => I, Position => J);
|
|
|
|
else
|
|
declare
|
|
J_Next : constant Cursor := Next (J);
|
|
|
|
begin
|
|
if J_Next = I then
|
|
Splice (Container, Before => J, Position => I);
|
|
|
|
else
|
|
pragma Assert (Container.Length >= 3);
|
|
|
|
Splice (Container, Before => I_Next, Position => J);
|
|
Splice (Container, Before => J_Next, Position => I);
|
|
end if;
|
|
end;
|
|
end if;
|
|
end;
|
|
end Swap_Links;
|
|
|
|
--------------------
|
|
-- Update_Element --
|
|
--------------------
|
|
|
|
procedure Update_Element
|
|
(Container : in out List;
|
|
Position : Cursor;
|
|
Process : not null access procedure (Element : in out Element_Type))
|
|
is
|
|
begin
|
|
if Position.Node = null then
|
|
raise Constraint_Error with "Position cursor has no element";
|
|
end if;
|
|
|
|
if Position.Container /= Container'Unchecked_Access then
|
|
raise Program_Error with
|
|
"Position cursor designates wrong container";
|
|
end if;
|
|
|
|
pragma Assert (Vet (Position), "bad cursor in Update_Element");
|
|
|
|
declare
|
|
B : Natural renames Container.Busy;
|
|
L : Natural renames Container.Lock;
|
|
|
|
begin
|
|
B := B + 1;
|
|
L := L + 1;
|
|
|
|
begin
|
|
Process (Position.Node.Element);
|
|
exception
|
|
when others =>
|
|
L := L - 1;
|
|
B := B - 1;
|
|
raise;
|
|
end;
|
|
|
|
L := L - 1;
|
|
B := B - 1;
|
|
end;
|
|
end Update_Element;
|
|
|
|
---------
|
|
-- Vet --
|
|
---------
|
|
|
|
function Vet (Position : Cursor) return Boolean is
|
|
begin
|
|
if Position.Node = null then
|
|
return Position.Container = null;
|
|
end if;
|
|
|
|
if Position.Container = null then
|
|
return False;
|
|
end if;
|
|
|
|
if Position.Node.Next = Position.Node then
|
|
return False;
|
|
end if;
|
|
|
|
if Position.Node.Prev = Position.Node then
|
|
return False;
|
|
end if;
|
|
|
|
declare
|
|
L : List renames Position.Container.all;
|
|
begin
|
|
if L.Length = 0 then
|
|
return False;
|
|
end if;
|
|
|
|
if L.First = null then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Last = null then
|
|
return False;
|
|
end if;
|
|
|
|
if L.First.Prev /= null then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Last.Next /= null then
|
|
return False;
|
|
end if;
|
|
|
|
if Position.Node.Prev = null
|
|
and then Position.Node /= L.First
|
|
then
|
|
return False;
|
|
end if;
|
|
|
|
-- If we get here, we know that this disjunction is true:
|
|
-- Position.Node.Prev /= null or else Position.Node = L.First
|
|
|
|
if Position.Node.Next = null
|
|
and then Position.Node /= L.Last
|
|
then
|
|
return False;
|
|
end if;
|
|
|
|
-- If we get here, we know that this disjunction is true:
|
|
-- Position.Node.Next /= null or else Position.Node = L.Last
|
|
|
|
if L.Length = 1 then
|
|
return L.First = L.Last;
|
|
end if;
|
|
|
|
if L.First = L.Last then
|
|
return False;
|
|
end if;
|
|
|
|
if L.First.Next = null then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Last.Prev = null then
|
|
return False;
|
|
end if;
|
|
|
|
if L.First.Next.Prev /= L.First then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Last.Prev.Next /= L.Last then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Length = 2 then
|
|
if L.First.Next /= L.Last then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Last.Prev /= L.First then
|
|
return False;
|
|
end if;
|
|
|
|
return True;
|
|
end if;
|
|
|
|
if L.First.Next = L.Last then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Last.Prev = L.First then
|
|
return False;
|
|
end if;
|
|
|
|
if Position.Node = L.First then -- eliminates ealier disjunct
|
|
return True;
|
|
end if;
|
|
|
|
-- If we get here, we know, per disjunctive syllogism (modus
|
|
-- tollendo ponens), that this predicate is true:
|
|
-- Position.Node.Prev /= null
|
|
|
|
if Position.Node = L.Last then -- eliminates earlier disjunct
|
|
return True;
|
|
end if;
|
|
|
|
-- If we get here, we know, per disjunctive syllogism (modus
|
|
-- tollendo ponens), that this predicate is true:
|
|
-- Position.Node.Next /= null
|
|
|
|
if Position.Node.Next.Prev /= Position.Node then
|
|
return False;
|
|
end if;
|
|
|
|
if Position.Node.Prev.Next /= Position.Node then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Length = 3 then
|
|
if L.First.Next /= Position.Node then
|
|
return False;
|
|
end if;
|
|
|
|
if L.Last.Prev /= Position.Node then
|
|
return False;
|
|
end if;
|
|
end if;
|
|
|
|
return True;
|
|
end;
|
|
end Vet;
|
|
|
|
-----------
|
|
-- Write --
|
|
-----------
|
|
|
|
procedure Write
|
|
(Stream : not null access Root_Stream_Type'Class;
|
|
Item : List)
|
|
is
|
|
Node : Node_Access := Item.First;
|
|
|
|
begin
|
|
Count_Type'Base'Write (Stream, Item.Length);
|
|
|
|
while Node /= null loop
|
|
Element_Type'Write (Stream, Node.Element);
|
|
Node := Node.Next;
|
|
end loop;
|
|
end Write;
|
|
|
|
procedure Write
|
|
(Stream : not null access Root_Stream_Type'Class;
|
|
Item : Cursor)
|
|
is
|
|
begin
|
|
raise Program_Error with "attempt to stream list cursor";
|
|
end Write;
|
|
|
|
end Ada.Containers.Doubly_Linked_Lists;
|