| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT LIBRARY COMPONENTS -- |
| -- -- |
| -- ADA.CONTAINERS.FORMAL_DOUBLY_LINKED_LISTS -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 2010-2014, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 3, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. -- |
| -- -- |
| -- As a special exception under Section 7 of GPL version 3, you are granted -- |
| -- additional permissions described in the GCC Runtime Library Exception, -- |
| -- version 3.1, as published by the Free Software Foundation. -- |
| -- -- |
| -- You should have received a copy of the GNU General Public License and -- |
| -- a copy of the GCC Runtime Library Exception along with this program; -- |
| -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- |
| -- <http://www.gnu.org/licenses/>. -- |
| ------------------------------------------------------------------------------ |
| |
| with System; use type System.Address; |
| |
| package body Ada.Containers.Formal_Doubly_Linked_Lists with |
| SPARK_Mode => Off |
| is |
| pragma Annotate (CodePeer, Skip_Analysis); |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| procedure Allocate |
| (Container : in out List; |
| New_Item : Element_Type; |
| New_Node : out Count_Type); |
| |
| procedure Allocate |
| (Container : in out List; |
| New_Node : out Count_Type); |
| |
| procedure Free |
| (Container : in out List; |
| X : Count_Type); |
| |
| procedure Insert_Internal |
| (Container : in out List; |
| Before : Count_Type; |
| New_Node : Count_Type); |
| |
| function Vet (L : List; Position : Cursor) return Boolean; |
| |
| --------- |
| -- "=" -- |
| --------- |
| |
| function "=" (Left, Right : List) return Boolean is |
| LI, RI : Count_Type; |
| |
| begin |
| if Left'Address = Right'Address then |
| return True; |
| end if; |
| |
| if Left.Length /= Right.Length then |
| return False; |
| end if; |
| |
| LI := Left.First; |
| RI := Left.First; |
| while LI /= 0 loop |
| if Left.Nodes (LI).Element /= Right.Nodes (LI).Element then |
| return False; |
| end if; |
| |
| LI := Left.Nodes (LI).Next; |
| RI := Right.Nodes (RI).Next; |
| end loop; |
| |
| return True; |
| end "="; |
| |
| -------------- |
| -- Allocate -- |
| -------------- |
| |
| procedure Allocate |
| (Container : in out List; |
| New_Item : Element_Type; |
| New_Node : out Count_Type) |
| is |
| N : Node_Array renames Container.Nodes; |
| |
| begin |
| if Container.Free >= 0 then |
| New_Node := Container.Free; |
| N (New_Node).Element := New_Item; |
| Container.Free := N (New_Node).Next; |
| |
| else |
| New_Node := abs Container.Free; |
| N (New_Node).Element := New_Item; |
| Container.Free := Container.Free - 1; |
| end if; |
| end Allocate; |
| |
| procedure Allocate |
| (Container : in out List; |
| New_Node : out Count_Type) |
| is |
| N : Node_Array renames Container.Nodes; |
| |
| begin |
| if Container.Free >= 0 then |
| New_Node := Container.Free; |
| Container.Free := N (New_Node).Next; |
| |
| else |
| New_Node := abs Container.Free; |
| Container.Free := Container.Free - 1; |
| end if; |
| end Allocate; |
| |
| ------------ |
| -- Append -- |
| ------------ |
| |
| procedure Append |
| (Container : in out List; |
| New_Item : Element_Type; |
| Count : Count_Type := 1) |
| is |
| begin |
| Insert (Container, No_Element, New_Item, Count); |
| end Append; |
| |
| ------------ |
| -- Assign -- |
| ------------ |
| |
| procedure Assign (Target : in out List; Source : List) is |
| N : Node_Array renames Source.Nodes; |
| J : Count_Type; |
| |
| begin |
| if Target'Address = Source'Address then |
| return; |
| end if; |
| |
| if Target.Capacity < Source.Length then |
| raise Constraint_Error with -- ??? |
| "Source length exceeds Target capacity"; |
| end if; |
| |
| Clear (Target); |
| |
| J := Source.First; |
| while J /= 0 loop |
| Append (Target, N (J).Element); |
| J := N (J).Next; |
| end loop; |
| end Assign; |
| |
| ----------- |
| -- Clear -- |
| ----------- |
| |
| procedure Clear (Container : in out List) is |
| N : Node_Array renames Container.Nodes; |
| X : Count_Type; |
| |
| begin |
| if Container.Length = 0 then |
| pragma Assert (Container.First = 0); |
| pragma Assert (Container.Last = 0); |
| return; |
| end if; |
| |
| pragma Assert (Container.First >= 1); |
| pragma Assert (Container.Last >= 1); |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| |
| while Container.Length > 1 loop |
| X := Container.First; |
| |
| Container.First := N (X).Next; |
| N (Container.First).Prev := 0; |
| |
| Container.Length := Container.Length - 1; |
| |
| Free (Container, X); |
| end loop; |
| |
| X := Container.First; |
| |
| Container.First := 0; |
| Container.Last := 0; |
| Container.Length := 0; |
| |
| Free (Container, X); |
| end Clear; |
| |
| -------------- |
| -- Contains -- |
| -------------- |
| |
| function Contains |
| (Container : List; |
| Item : Element_Type) return Boolean |
| is |
| begin |
| return Find (Container, Item) /= No_Element; |
| end Contains; |
| |
| ---------- |
| -- Copy -- |
| ---------- |
| |
| function Copy |
| (Source : List; |
| Capacity : Count_Type := 0) return List |
| is |
| C : constant Count_Type := Count_Type'Max (Source.Capacity, Capacity); |
| N : Count_Type; |
| P : List (C); |
| |
| begin |
| if 0 < Capacity and then Capacity < Source.Capacity then |
| raise Capacity_Error; |
| end if; |
| |
| N := 1; |
| while N <= Source.Capacity loop |
| P.Nodes (N).Prev := Source.Nodes (N).Prev; |
| P.Nodes (N).Next := Source.Nodes (N).Next; |
| P.Nodes (N).Element := Source.Nodes (N).Element; |
| N := N + 1; |
| end loop; |
| |
| P.Free := Source.Free; |
| P.Length := Source.Length; |
| P.First := Source.First; |
| P.Last := Source.Last; |
| |
| if P.Free >= 0 then |
| N := Source.Capacity + 1; |
| while N <= C loop |
| Free (P, N); |
| N := N + 1; |
| end loop; |
| end if; |
| |
| return P; |
| end Copy; |
| |
| --------------------- |
| -- Current_To_Last -- |
| --------------------- |
| |
| function Current_To_Last |
| (Container : List; |
| Current : Cursor) return List is |
| Curs : Cursor := First (Container); |
| C : List (Container.Capacity) := Copy (Container, Container.Capacity); |
| Node : Count_Type; |
| |
| begin |
| if Curs = No_Element then |
| Clear (C); |
| return C; |
| end if; |
| |
| if Current /= No_Element and not Has_Element (Container, Current) then |
| raise Constraint_Error; |
| end if; |
| |
| while Curs.Node /= Current.Node loop |
| Node := Curs.Node; |
| Delete (C, Curs); |
| Curs := Next (Container, (Node => Node)); |
| end loop; |
| |
| return C; |
| end Current_To_Last; |
| |
| ------------ |
| -- Delete -- |
| ------------ |
| |
| procedure Delete |
| (Container : in out List; |
| Position : in out Cursor; |
| Count : Count_Type := 1) |
| is |
| N : Node_Array renames Container.Nodes; |
| X : Count_Type; |
| |
| begin |
| if not Has_Element (Container => Container, |
| Position => Position) |
| then |
| raise Constraint_Error with |
| "Position cursor has no element"; |
| end if; |
| |
| pragma Assert (Vet (Container, Position), "bad cursor in Delete"); |
| pragma Assert (Container.First >= 1); |
| pragma Assert (Container.Last >= 1); |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| |
| if Position.Node = Container.First then |
| Delete_First (Container, Count); |
| Position := No_Element; |
| return; |
| end if; |
| |
| if Count = 0 then |
| Position := No_Element; |
| return; |
| end if; |
| |
| for Index in 1 .. Count loop |
| pragma Assert (Container.Length >= 2); |
| |
| X := Position.Node; |
| Container.Length := Container.Length - 1; |
| |
| if X = Container.Last then |
| Position := No_Element; |
| |
| Container.Last := N (X).Prev; |
| N (Container.Last).Next := 0; |
| |
| Free (Container, X); |
| return; |
| end if; |
| |
| Position.Node := N (X).Next; |
| pragma Assert (N (Position.Node).Prev >= 0); |
| |
| N (N (X).Next).Prev := N (X).Prev; |
| N (N (X).Prev).Next := N (X).Next; |
| |
| Free (Container, X); |
| end loop; |
| Position := No_Element; |
| end Delete; |
| |
| ------------------ |
| -- Delete_First -- |
| ------------------ |
| |
| procedure Delete_First |
| (Container : in out List; |
| Count : Count_Type := 1) |
| is |
| N : Node_Array renames Container.Nodes; |
| X : Count_Type; |
| |
| begin |
| if Count >= Container.Length then |
| Clear (Container); |
| return; |
| end if; |
| |
| if Count = 0 then |
| return; |
| end if; |
| |
| for J in 1 .. Count loop |
| X := Container.First; |
| pragma Assert (N (N (X).Next).Prev = Container.First); |
| |
| Container.First := N (X).Next; |
| N (Container.First).Prev := 0; |
| |
| Container.Length := Container.Length - 1; |
| |
| Free (Container, X); |
| end loop; |
| end Delete_First; |
| |
| ----------------- |
| -- Delete_Last -- |
| ----------------- |
| |
| procedure Delete_Last |
| (Container : in out List; |
| Count : Count_Type := 1) |
| is |
| N : Node_Array renames Container.Nodes; |
| X : Count_Type; |
| |
| begin |
| if Count >= Container.Length then |
| Clear (Container); |
| return; |
| end if; |
| |
| if Count = 0 then |
| return; |
| end if; |
| |
| for J in 1 .. Count loop |
| X := Container.Last; |
| pragma Assert (N (N (X).Prev).Next = Container.Last); |
| |
| Container.Last := N (X).Prev; |
| N (Container.Last).Next := 0; |
| |
| Container.Length := Container.Length - 1; |
| |
| Free (Container, X); |
| end loop; |
| end Delete_Last; |
| |
| ------------- |
| -- Element -- |
| ------------- |
| |
| function Element |
| (Container : List; |
| Position : Cursor) return Element_Type |
| is |
| begin |
| if not Has_Element (Container => Container, Position => Position) then |
| raise Constraint_Error with |
| "Position cursor has no element"; |
| end if; |
| |
| return Container.Nodes (Position.Node).Element; |
| end Element; |
| |
| ---------- |
| -- Find -- |
| ---------- |
| |
| function Find |
| (Container : List; |
| Item : Element_Type; |
| Position : Cursor := No_Element) return Cursor |
| is |
| From : Count_Type := Position.Node; |
| |
| begin |
| if From = 0 and Container.Length = 0 then |
| return No_Element; |
| end if; |
| |
| if From = 0 then |
| From := Container.First; |
| end if; |
| |
| if Position.Node /= 0 and then |
| not Has_Element (Container, Position) |
| then |
| raise Constraint_Error with |
| "Position cursor has no element"; |
| end if; |
| |
| while From /= 0 loop |
| if Container.Nodes (From).Element = Item then |
| return (Node => From); |
| end if; |
| |
| From := Container.Nodes (From).Next; |
| end loop; |
| |
| return No_Element; |
| end Find; |
| |
| ----------- |
| -- First -- |
| ----------- |
| |
| function First (Container : List) return Cursor is |
| begin |
| if Container.First = 0 then |
| return No_Element; |
| end if; |
| |
| return (Node => Container.First); |
| end First; |
| |
| ------------------- |
| -- First_Element -- |
| ------------------- |
| |
| function First_Element (Container : List) return Element_Type is |
| F : constant Count_Type := Container.First; |
| begin |
| if F = 0 then |
| raise Constraint_Error with "list is empty"; |
| else |
| return Container.Nodes (F).Element; |
| end if; |
| end First_Element; |
| |
| ----------------------- |
| -- First_To_Previous -- |
| ----------------------- |
| |
| function First_To_Previous |
| (Container : List; |
| Current : Cursor) return List |
| is |
| Curs : Cursor := Current; |
| C : List (Container.Capacity) := Copy (Container, Container.Capacity); |
| Node : Count_Type; |
| |
| begin |
| if Curs = No_Element then |
| return C; |
| |
| elsif not Has_Element (Container, Curs) then |
| raise Constraint_Error; |
| |
| else |
| while Curs.Node /= 0 loop |
| Node := Curs.Node; |
| Delete (C, Curs); |
| Curs := Next (Container, (Node => Node)); |
| end loop; |
| |
| return C; |
| end if; |
| end First_To_Previous; |
| |
| ---------- |
| -- Free -- |
| ---------- |
| |
| procedure Free |
| (Container : in out List; |
| X : Count_Type) |
| is |
| pragma Assert (X > 0); |
| pragma Assert (X <= Container.Capacity); |
| |
| N : Node_Array renames Container.Nodes; |
| |
| begin |
| N (X).Prev := -1; -- Node is deallocated (not on active list) |
| |
| if Container.Free >= 0 then |
| N (X).Next := Container.Free; |
| Container.Free := X; |
| |
| elsif X + 1 = abs Container.Free then |
| N (X).Next := 0; -- Not strictly necessary, but marginally safer |
| Container.Free := Container.Free + 1; |
| |
| else |
| Container.Free := abs Container.Free; |
| |
| if Container.Free > Container.Capacity then |
| Container.Free := 0; |
| |
| else |
| for J in Container.Free .. Container.Capacity - 1 loop |
| N (J).Next := J + 1; |
| end loop; |
| |
| N (Container.Capacity).Next := 0; |
| end if; |
| |
| N (X).Next := Container.Free; |
| Container.Free := X; |
| end if; |
| end Free; |
| |
| --------------------- |
| -- Generic_Sorting -- |
| --------------------- |
| |
| package body Generic_Sorting is |
| |
| --------------- |
| -- Is_Sorted -- |
| --------------- |
| |
| function Is_Sorted (Container : List) return Boolean is |
| Nodes : Node_Array renames Container.Nodes; |
| Node : Count_Type := Container.First; |
| |
| begin |
| for J in 2 .. Container.Length loop |
| if Nodes (Nodes (Node).Next).Element < Nodes (Node).Element then |
| return False; |
| else |
| Node := Nodes (Node).Next; |
| end if; |
| end loop; |
| |
| return True; |
| end Is_Sorted; |
| |
| ----------- |
| -- Merge -- |
| ----------- |
| |
| procedure Merge |
| (Target : in out List; |
| Source : in out List) |
| is |
| LN : Node_Array renames Target.Nodes; |
| RN : Node_Array renames Source.Nodes; |
| LI : Cursor; |
| RI : Cursor; |
| |
| begin |
| if Target'Address = Source'Address then |
| return; |
| end if; |
| |
| LI := First (Target); |
| RI := First (Source); |
| while RI.Node /= 0 loop |
| pragma Assert (RN (RI.Node).Next = 0 |
| or else not (RN (RN (RI.Node).Next).Element < |
| RN (RI.Node).Element)); |
| |
| if LI.Node = 0 then |
| Splice (Target, No_Element, Source); |
| return; |
| end if; |
| |
| pragma Assert (LN (LI.Node).Next = 0 |
| or else not (LN (LN (LI.Node).Next).Element < |
| LN (LI.Node).Element)); |
| |
| if RN (RI.Node).Element < LN (LI.Node).Element then |
| declare |
| RJ : Cursor := RI; |
| pragma Warnings (Off, RJ); |
| begin |
| RI.Node := RN (RI.Node).Next; |
| Splice (Target, LI, Source, RJ); |
| end; |
| |
| else |
| LI.Node := LN (LI.Node).Next; |
| end if; |
| end loop; |
| end Merge; |
| |
| ---------- |
| -- Sort -- |
| ---------- |
| |
| procedure Sort (Container : in out List) is |
| N : Node_Array renames Container.Nodes; |
| |
| procedure Partition (Pivot, Back : Count_Type); |
| procedure Sort (Front, Back : Count_Type); |
| |
| --------------- |
| -- Partition -- |
| --------------- |
| |
| procedure Partition (Pivot, Back : Count_Type) is |
| Node : Count_Type; |
| |
| begin |
| Node := N (Pivot).Next; |
| while Node /= Back loop |
| if N (Node).Element < N (Pivot).Element then |
| declare |
| Prev : constant Count_Type := N (Node).Prev; |
| Next : constant Count_Type := N (Node).Next; |
| |
| begin |
| N (Prev).Next := Next; |
| |
| if Next = 0 then |
| Container.Last := Prev; |
| else |
| N (Next).Prev := Prev; |
| end if; |
| |
| N (Node).Next := Pivot; |
| N (Node).Prev := N (Pivot).Prev; |
| |
| N (Pivot).Prev := Node; |
| |
| if N (Node).Prev = 0 then |
| Container.First := Node; |
| else |
| N (N (Node).Prev).Next := Node; |
| end if; |
| |
| Node := Next; |
| end; |
| |
| else |
| Node := N (Node).Next; |
| end if; |
| end loop; |
| end Partition; |
| |
| ---------- |
| -- Sort -- |
| ---------- |
| |
| procedure Sort (Front, Back : Count_Type) is |
| Pivot : Count_Type; |
| |
| begin |
| if Front = 0 then |
| Pivot := Container.First; |
| else |
| Pivot := N (Front).Next; |
| end if; |
| |
| if Pivot /= Back then |
| Partition (Pivot, Back); |
| Sort (Front, Pivot); |
| Sort (Pivot, Back); |
| end if; |
| end Sort; |
| |
| -- Start of processing for Sort |
| |
| begin |
| if Container.Length <= 1 then |
| return; |
| end if; |
| |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| |
| Sort (Front => 0, Back => 0); |
| |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| end Sort; |
| |
| end Generic_Sorting; |
| |
| ----------------- |
| -- Has_Element -- |
| ----------------- |
| |
| function Has_Element (Container : List; Position : Cursor) return Boolean is |
| begin |
| if Position.Node = 0 then |
| return False; |
| end if; |
| |
| return Container.Nodes (Position.Node).Prev /= -1; |
| end Has_Element; |
| |
| ------------ |
| -- Insert -- |
| ------------ |
| |
| procedure Insert |
| (Container : in out List; |
| Before : Cursor; |
| New_Item : Element_Type; |
| Position : out Cursor; |
| Count : Count_Type := 1) |
| is |
| J : Count_Type; |
| |
| begin |
| if Before.Node /= 0 then |
| pragma Assert (Vet (Container, Before), "bad cursor in Insert"); |
| end if; |
| |
| if Count = 0 then |
| Position := Before; |
| return; |
| end if; |
| |
| if Container.Length > Container.Capacity - Count then |
| raise Constraint_Error with "new length exceeds capacity"; |
| end if; |
| |
| Allocate (Container, New_Item, New_Node => J); |
| Insert_Internal (Container, Before.Node, New_Node => J); |
| Position := (Node => J); |
| |
| for Index in 2 .. Count loop |
| Allocate (Container, New_Item, New_Node => J); |
| Insert_Internal (Container, Before.Node, New_Node => J); |
| end loop; |
| end Insert; |
| |
| procedure Insert |
| (Container : in out List; |
| Before : Cursor; |
| New_Item : Element_Type; |
| Count : Count_Type := 1) |
| is |
| Position : Cursor; |
| 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 |
| J : Count_Type; |
| |
| begin |
| if Before.Node /= 0 then |
| pragma Assert (Vet (Container, Before), "bad cursor in Insert"); |
| end if; |
| |
| if Count = 0 then |
| Position := Before; |
| return; |
| end if; |
| |
| if Container.Length > Container.Capacity - Count then |
| raise Constraint_Error with "new length exceeds capacity"; |
| end if; |
| |
| Allocate (Container, New_Node => J); |
| Insert_Internal (Container, Before.Node, New_Node => J); |
| Position := (Node => J); |
| |
| for Index in 2 .. Count loop |
| Allocate (Container, New_Node => J); |
| Insert_Internal (Container, Before.Node, New_Node => J); |
| end loop; |
| end Insert; |
| |
| --------------------- |
| -- Insert_Internal -- |
| --------------------- |
| |
| procedure Insert_Internal |
| (Container : in out List; |
| Before : Count_Type; |
| New_Node : Count_Type) |
| is |
| N : Node_Array renames Container.Nodes; |
| |
| begin |
| if Container.Length = 0 then |
| pragma Assert (Before = 0); |
| pragma Assert (Container.First = 0); |
| pragma Assert (Container.Last = 0); |
| |
| Container.First := New_Node; |
| Container.Last := New_Node; |
| |
| N (Container.First).Prev := 0; |
| N (Container.Last).Next := 0; |
| |
| elsif Before = 0 then |
| pragma Assert (N (Container.Last).Next = 0); |
| |
| N (Container.Last).Next := New_Node; |
| N (New_Node).Prev := Container.Last; |
| |
| Container.Last := New_Node; |
| N (Container.Last).Next := 0; |
| |
| elsif Before = Container.First then |
| pragma Assert (N (Container.First).Prev = 0); |
| |
| N (Container.First).Prev := New_Node; |
| N (New_Node).Next := Container.First; |
| |
| Container.First := New_Node; |
| N (Container.First).Prev := 0; |
| |
| else |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| |
| N (New_Node).Next := Before; |
| N (New_Node).Prev := N (Before).Prev; |
| |
| N (N (Before).Prev).Next := New_Node; |
| N (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 Length (Container) = 0; |
| end Is_Empty; |
| |
| ---------- |
| -- Last -- |
| ---------- |
| |
| function Last (Container : List) return Cursor is |
| begin |
| if Container.Last = 0 then |
| return No_Element; |
| end if; |
| |
| return (Node => Container.Last); |
| end Last; |
| |
| ------------------ |
| -- Last_Element -- |
| ------------------ |
| |
| function Last_Element (Container : List) return Element_Type is |
| L : constant Count_Type := Container.Last; |
| begin |
| if L = 0 then |
| raise Constraint_Error with "list is empty"; |
| else |
| return Container.Nodes (L).Element; |
| end if; |
| 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 |
| N : Node_Array renames Source.Nodes; |
| X : Count_Type; |
| |
| begin |
| if Target'Address = Source'Address then |
| return; |
| end if; |
| |
| if Target.Capacity < Source.Length then |
| raise Constraint_Error with -- ??? |
| "Source length exceeds Target capacity"; |
| end if; |
| |
| Clear (Target); |
| |
| while Source.Length > 1 loop |
| pragma Assert (Source.First in 1 .. Source.Capacity); |
| pragma Assert (Source.Last /= Source.First); |
| pragma Assert (N (Source.First).Prev = 0); |
| pragma Assert (N (Source.Last).Next = 0); |
| |
| -- Copy first element from Source to Target |
| |
| X := Source.First; |
| Append (Target, N (X).Element); -- optimize away??? |
| |
| -- Unlink first node of Source |
| |
| Source.First := N (X).Next; |
| N (Source.First).Prev := 0; |
| |
| Source.Length := Source.Length - 1; |
| |
| -- The representation invariants for Source have been restored. It is |
| -- now safe to free the unlinked node, without fear of corrupting the |
| -- active links of Source. |
| |
| -- Note that the algorithm we use here models similar algorithms used |
| -- in the unbounded form of the doubly-linked list container. In that |
| -- case, Free is an instantation of Unchecked_Deallocation, which can |
| -- fail (because PE will be raised if controlled Finalize fails), so |
| -- we must defer the call until the last step. Here in the bounded |
| -- form, Free merely links the node we have just "deallocated" onto a |
| -- list of inactive nodes, so technically Free cannot fail. However, |
| -- for consistency, we handle Free the same way here as we do for the |
| -- unbounded form, with the pessimistic assumption that it can fail. |
| |
| Free (Source, X); |
| end loop; |
| |
| if Source.Length = 1 then |
| pragma Assert (Source.First in 1 .. Source.Capacity); |
| pragma Assert (Source.Last = Source.First); |
| pragma Assert (N (Source.First).Prev = 0); |
| pragma Assert (N (Source.Last).Next = 0); |
| |
| -- Copy element from Source to Target |
| |
| X := Source.First; |
| Append (Target, N (X).Element); |
| |
| -- Unlink node of Source |
| |
| Source.First := 0; |
| Source.Last := 0; |
| Source.Length := 0; |
| |
| -- Return the unlinked node to the free store |
| |
| Free (Source, X); |
| end if; |
| end Move; |
| |
| ---------- |
| -- Next -- |
| ---------- |
| |
| procedure Next (Container : List; Position : in out Cursor) is |
| begin |
| Position := Next (Container, Position); |
| end Next; |
| |
| function Next (Container : List; Position : Cursor) return Cursor is |
| begin |
| if Position.Node = 0 then |
| return No_Element; |
| end if; |
| |
| if not Has_Element (Container, Position) then |
| raise Program_Error with "Position cursor has no element"; |
| end if; |
| |
| return (Node => Container.Nodes (Position.Node).Next); |
| 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 (Container : List; Position : in out Cursor) is |
| begin |
| Position := Previous (Container, Position); |
| end Previous; |
| |
| function Previous (Container : List; Position : Cursor) return Cursor is |
| begin |
| if Position.Node = 0 then |
| return No_Element; |
| end if; |
| |
| if not Has_Element (Container, Position) then |
| raise Program_Error with "Position cursor has no element"; |
| end if; |
| |
| return (Node => Container.Nodes (Position.Node).Prev); |
| end Previous; |
| |
| --------------------- |
| -- Replace_Element -- |
| --------------------- |
| |
| procedure Replace_Element |
| (Container : in out List; |
| Position : Cursor; |
| New_Item : Element_Type) |
| is |
| begin |
| if not Has_Element (Container, Position) then |
| raise Constraint_Error with "Position cursor has no element"; |
| end if; |
| |
| pragma Assert |
| (Vet (Container, Position), "bad cursor in Replace_Element"); |
| |
| Container.Nodes (Position.Node).Element := New_Item; |
| end Replace_Element; |
| |
| ---------------------- |
| -- Reverse_Elements -- |
| ---------------------- |
| |
| procedure Reverse_Elements (Container : in out List) is |
| N : Node_Array renames Container.Nodes; |
| I : Count_Type := Container.First; |
| J : Count_Type := Container.Last; |
| |
| procedure Swap (L, R : Count_Type); |
| |
| ---------- |
| -- Swap -- |
| ---------- |
| |
| procedure Swap (L, R : Count_Type) is |
| LN : constant Count_Type := N (L).Next; |
| LP : constant Count_Type := N (L).Prev; |
| |
| RN : constant Count_Type := N (R).Next; |
| RP : constant Count_Type := N (R).Prev; |
| |
| begin |
| if LP /= 0 then |
| N (LP).Next := R; |
| end if; |
| |
| if RN /= 0 then |
| N (RN).Prev := L; |
| end if; |
| |
| N (L).Next := RN; |
| N (R).Prev := LP; |
| |
| if LN = R then |
| pragma Assert (RP = L); |
| |
| N (L).Prev := R; |
| N (R).Next := L; |
| |
| else |
| N (L).Prev := RP; |
| N (RP).Next := L; |
| |
| N (R).Next := LN; |
| N (LN).Prev := R; |
| end if; |
| end Swap; |
| |
| -- Start of processing for Reverse_Elements |
| |
| begin |
| if Container.Length <= 1 then |
| return; |
| end if; |
| |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| |
| Container.First := J; |
| Container.Last := I; |
| loop |
| Swap (L => I, R => J); |
| |
| J := N (J).Next; |
| exit when I = J; |
| |
| I := N (I).Prev; |
| exit when I = J; |
| |
| Swap (L => J, R => I); |
| |
| I := N (I).Next; |
| exit when I = J; |
| |
| J := N (J).Prev; |
| exit when I = J; |
| end loop; |
| |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| end Reverse_Elements; |
| |
| ------------------ |
| -- Reverse_Find -- |
| ------------------ |
| |
| function Reverse_Find |
| (Container : List; |
| Item : Element_Type; |
| Position : Cursor := No_Element) return Cursor |
| is |
| CFirst : Count_Type := Position.Node; |
| |
| begin |
| if CFirst = 0 then |
| CFirst := Container.First; |
| end if; |
| |
| if Container.Length = 0 then |
| return No_Element; |
| |
| else |
| while CFirst /= 0 loop |
| if Container.Nodes (CFirst).Element = Item then |
| return (Node => CFirst); |
| else |
| CFirst := Container.Nodes (CFirst).Prev; |
| end if; |
| end loop; |
| |
| return No_Element; |
| end if; |
| end Reverse_Find; |
| |
| ------------ |
| -- Splice -- |
| ------------ |
| |
| procedure Splice |
| (Target : in out List; |
| Before : Cursor; |
| Source : in out List) |
| is |
| SN : Node_Array renames Source.Nodes; |
| |
| begin |
| if Before.Node /= 0 then |
| pragma Assert (Vet (Target, Before), "bad cursor in Splice"); |
| end if; |
| |
| if Target'Address = Source'Address |
| or else Source.Length = 0 |
| then |
| return; |
| end if; |
| |
| pragma Assert (SN (Source.First).Prev = 0); |
| pragma Assert (SN (Source.Last).Next = 0); |
| |
| if Target.Length > Count_Type'Base'Last - Source.Length then |
| raise Constraint_Error with "new length exceeds maximum"; |
| end if; |
| |
| if Target.Length + Source.Length > Target.Capacity then |
| raise Constraint_Error; |
| end if; |
| |
| loop |
| Insert (Target, Before, SN (Source.Last).Element); |
| Delete_Last (Source); |
| exit when Is_Empty (Source); |
| end loop; |
| end Splice; |
| |
| procedure Splice |
| (Target : in out List; |
| Before : Cursor; |
| Source : in out List; |
| Position : in out Cursor) |
| is |
| Target_Position : Cursor; |
| |
| begin |
| if Target'Address = Source'Address then |
| Splice (Target, Before, Position); |
| return; |
| end if; |
| |
| if Position.Node = 0 then |
| raise Constraint_Error with "Position cursor has no element"; |
| end if; |
| |
| pragma Assert (Vet (Source, Position), "bad Position cursor in Splice"); |
| |
| if Target.Length >= Target.Capacity then |
| raise Constraint_Error; |
| end if; |
| |
| Insert |
| (Container => Target, |
| Before => Before, |
| New_Item => Source.Nodes (Position.Node).Element, |
| Position => Target_Position); |
| |
| Delete (Source, Position); |
| Position := Target_Position; |
| end Splice; |
| |
| procedure Splice |
| (Container : in out List; |
| Before : Cursor; |
| Position : Cursor) |
| is |
| N : Node_Array renames Container.Nodes; |
| |
| begin |
| if Before.Node /= 0 then |
| pragma Assert |
| (Vet (Container, Before), "bad Before cursor in Splice"); |
| end if; |
| |
| if Position.Node = 0 then |
| raise Constraint_Error with "Position cursor has no element"; |
| end if; |
| |
| pragma Assert |
| (Vet (Container, Position), "bad Position cursor in Splice"); |
| |
| if Position.Node = Before.Node |
| or else N (Position.Node).Next = Before.Node |
| then |
| return; |
| end if; |
| |
| pragma Assert (Container.Length >= 2); |
| |
| if Before.Node = 0 then |
| pragma Assert (Position.Node /= Container.Last); |
| |
| if Position.Node = Container.First then |
| Container.First := N (Position.Node).Next; |
| N (Container.First).Prev := 0; |
| |
| else |
| N (N (Position.Node).Prev).Next := N (Position.Node).Next; |
| N (N (Position.Node).Next).Prev := N (Position.Node).Prev; |
| end if; |
| |
| N (Container.Last).Next := Position.Node; |
| N (Position.Node).Prev := Container.Last; |
| |
| Container.Last := Position.Node; |
| N (Container.Last).Next := 0; |
| |
| return; |
| end if; |
| |
| if Before.Node = Container.First then |
| pragma Assert (Position.Node /= Container.First); |
| |
| if Position.Node = Container.Last then |
| Container.Last := N (Position.Node).Prev; |
| N (Container.Last).Next := 0; |
| |
| else |
| N (N (Position.Node).Prev).Next := N (Position.Node).Next; |
| N (N (Position.Node).Next).Prev := N (Position.Node).Prev; |
| end if; |
| |
| N (Container.First).Prev := Position.Node; |
| N (Position.Node).Next := Container.First; |
| |
| Container.First := Position.Node; |
| N (Container.First).Prev := 0; |
| |
| return; |
| end if; |
| |
| if Position.Node = Container.First then |
| Container.First := N (Position.Node).Next; |
| N (Container.First).Prev := 0; |
| |
| elsif Position.Node = Container.Last then |
| Container.Last := N (Position.Node).Prev; |
| N (Container.Last).Next := 0; |
| |
| else |
| N (N (Position.Node).Prev).Next := N (Position.Node).Next; |
| N (N (Position.Node).Next).Prev := N (Position.Node).Prev; |
| end if; |
| |
| N (N (Before.Node).Prev).Next := Position.Node; |
| N (Position.Node).Prev := N (Before.Node).Prev; |
| |
| N (Before.Node).Prev := Position.Node; |
| N (Position.Node).Next := Before.Node; |
| |
| pragma Assert (N (Container.First).Prev = 0); |
| pragma Assert (N (Container.Last).Next = 0); |
| end Splice; |
| |
| ------------------ |
| -- Strict_Equal -- |
| ------------------ |
| |
| function Strict_Equal (Left, Right : List) return Boolean is |
| CL : Count_Type := Left.First; |
| CR : Count_Type := Right.First; |
| |
| begin |
| while CL /= 0 or CR /= 0 loop |
| if CL /= CR or else |
| Left.Nodes (CL).Element /= Right.Nodes (CL).Element |
| then |
| return False; |
| end if; |
| |
| CL := Left.Nodes (CL).Next; |
| CR := Right.Nodes (CR).Next; |
| end loop; |
| |
| return True; |
| end Strict_Equal; |
| |
| ---------- |
| -- Swap -- |
| ---------- |
| |
| procedure Swap |
| (Container : in out List; |
| I, J : Cursor) |
| is |
| begin |
| if I.Node = 0 then |
| raise Constraint_Error with "I cursor has no element"; |
| end if; |
| |
| if J.Node = 0 then |
| raise Constraint_Error with "J cursor has no element"; |
| end if; |
| |
| if I.Node = J.Node then |
| return; |
| end if; |
| |
| pragma Assert (Vet (Container, I), "bad I cursor in Swap"); |
| pragma Assert (Vet (Container, J), "bad J cursor in Swap"); |
| |
| declare |
| NN : Node_Array renames Container.Nodes; |
| NI : Node_Type renames NN (I.Node); |
| NJ : Node_Type renames NN (J.Node); |
| |
| EI_Copy : constant Element_Type := NI.Element; |
| |
| begin |
| NI.Element := NJ.Element; |
| NJ.Element := EI_Copy; |
| end; |
| end Swap; |
| |
| ---------------- |
| -- Swap_Links -- |
| ---------------- |
| |
| procedure Swap_Links |
| (Container : in out List; |
| I, J : Cursor) |
| is |
| I_Next, J_Next : Cursor; |
| |
| begin |
| if I.Node = 0 then |
| raise Constraint_Error with "I cursor has no element"; |
| end if; |
| |
| if J.Node = 0 then |
| raise Constraint_Error with "J cursor has no element"; |
| end if; |
| |
| if I.Node = J.Node then |
| return; |
| end if; |
| |
| pragma Assert (Vet (Container, I), "bad I cursor in Swap_Links"); |
| pragma Assert (Vet (Container, J), "bad J cursor in Swap_Links"); |
| |
| I_Next := Next (Container, I); |
| |
| if I_Next = J then |
| Splice (Container, Before => I, Position => J); |
| |
| else |
| J_Next := Next (Container, J); |
| |
| 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 if; |
| end Swap_Links; |
| |
| --------- |
| -- Vet -- |
| --------- |
| |
| function Vet (L : List; Position : Cursor) return Boolean is |
| N : Node_Array renames L.Nodes; |
| |
| begin |
| if L.Length = 0 then |
| return False; |
| end if; |
| |
| if L.First = 0 then |
| return False; |
| end if; |
| |
| if L.Last = 0 then |
| return False; |
| end if; |
| |
| if Position.Node > L.Capacity then |
| return False; |
| end if; |
| |
| if N (Position.Node).Prev < 0 |
| or else N (Position.Node).Prev > L.Capacity |
| then |
| return False; |
| end if; |
| |
| if N (Position.Node).Next > L.Capacity then |
| return False; |
| end if; |
| |
| if N (L.First).Prev /= 0 then |
| return False; |
| end if; |
| |
| if N (L.Last).Next /= 0 then |
| return False; |
| end if; |
| |
| if N (Position.Node).Prev = 0 |
| and then Position.Node /= L.First |
| then |
| return False; |
| end if; |
| |
| if N (Position.Node).Next = 0 |
| and then Position.Node /= L.Last |
| then |
| return False; |
| end if; |
| |
| if L.Length = 1 then |
| return L.First = L.Last; |
| end if; |
| |
| if L.First = L.Last then |
| return False; |
| end if; |
| |
| if N (L.First).Next = 0 then |
| return False; |
| end if; |
| |
| if N (L.Last).Prev = 0 then |
| return False; |
| end if; |
| |
| if N (N (L.First).Next).Prev /= L.First then |
| return False; |
| end if; |
| |
| if N (N (L.Last).Prev).Next /= L.Last then |
| return False; |
| end if; |
| |
| if L.Length = 2 then |
| if N (L.First).Next /= L.Last then |
| return False; |
| end if; |
| |
| if N (L.Last).Prev /= L.First then |
| return False; |
| end if; |
| |
| return True; |
| end if; |
| |
| if N (L.First).Next = L.Last then |
| return False; |
| end if; |
| |
| if N (L.Last).Prev = L.First then |
| return False; |
| end if; |
| |
| if Position.Node = L.First then |
| return True; |
| end if; |
| |
| if Position.Node = L.Last then |
| return True; |
| end if; |
| |
| if N (Position.Node).Next = 0 then |
| return False; |
| end if; |
| |
| if N (Position.Node).Prev = 0 then |
| return False; |
| end if; |
| |
| if N (N (Position.Node).Next).Prev /= Position.Node then |
| return False; |
| end if; |
| |
| if N (N (Position.Node).Prev).Next /= Position.Node then |
| return False; |
| end if; |
| |
| if L.Length = 3 then |
| if N (L.First).Next /= Position.Node then |
| return False; |
| end if; |
| |
| if N (L.Last).Prev /= Position.Node then |
| return False; |
| end if; |
| end if; |
| |
| return True; |
| end Vet; |
| |
| end Ada.Containers.Formal_Doubly_Linked_Lists; |
