with System; use type System.Address;
with Ada.Unchecked_Deallocation;
package body Ada.Containers.Indefinite_Doubly_Linked_Lists is
procedure Free is
new Ada.Unchecked_Deallocation (Node_Type, Node_Access);
procedure Free is
new Ada.Unchecked_Deallocation (Element_Type, Element_Access);
procedure Delete_Node
(Container : in out List;
Node : in out Node_Access);
procedure Insert_Internal
(Container : in out List;
Before : Node_Access;
New_Node : Node_Access);
function "=" (Left, Right : List) return Boolean is
L : Node_Access;
R : Node_Access;
begin
if Left'Address = Right'Address then
return True;
end if;
if Left.Length /= Right.Length then
return False;
end if;
L := Left.First;
R := Right.First;
for J in 1 .. Left.Length loop
if L.Element = null then
if R.Element /= null then
return False;
end if;
elsif R.Element = null then
return False;
elsif L.Element.all /= R.Element.all then
return False;
end if;
L := L.Next;
R := R.Next;
end loop;
return True;
end "=";
procedure Adjust (Container : in out List) is
Src : Node_Access := Container.First;
Dst : Node_Access;
begin
if Src = null then
pragma Assert (Container.Last = null);
pragma Assert (Container.Length = 0);
return;
end if;
pragma Assert (Container.First.Prev = null);
pragma Assert (Container.Last.Next = null);
pragma Assert (Container.Length > 0);
Container.First := null;
Container.Last := null;
Container.Length := 0;
Dst := new Node_Type'(null, null, null);
if Src.Element /= null then
begin
Dst.Element := new Element_Type'(Src.Element.all);
exception
when others =>
Free (Dst);
raise;
end;
end if;
Container.First := Dst;
Container.Last := Dst;
loop
Container.Length := Container.Length + 1;
Src := Src.Next;
exit when Src = null;
Dst := new Node_Type'(null, Prev => Container.Last, Next => null);
if Src.Element /= null then
begin
Dst.Element := new Element_Type'(Src.Element.all);
exception
when others =>
Free (Dst);
raise;
end;
end if;
Container.Last.Next := Dst;
Container.Last := Dst;
end loop;
end Adjust;
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;
procedure Clear (Container : in out List) is
begin
Delete_Last (Container, Count => Container.Length);
end Clear;
function Contains
(Container : List;
Item : Element_Type) return Boolean is
begin
return Find (Container, Item) /= No_Element;
end Contains;
procedure Delete
(Container : in out List;
Position : in out Cursor;
Count : Count_Type := 1)
is
begin
if Position = No_Element then
return;
end if;
if Position.Container /= List_Access'(Container'Unchecked_Access) then
raise Program_Error;
end if;
for Index in 1 .. Count loop
Delete_Node (Container, Position.Node);
if Position.Node = null then
Position.Container := null;
return;
end if;
end loop;
end Delete;
procedure Delete_First
(Container : in out List;
Count : Count_Type := 1)
is
Node : Node_Access := Container.First;
begin
for J in 1 .. Count_Type'Min (Count, Container.Length) loop
Delete_Node (Container, Node);
end loop;
end Delete_First;
procedure Delete_Last
(Container : in out List;
Count : Count_Type := 1)
is
Node : Node_Access;
begin
for J in 1 .. Count_Type'Min (Count, Container.Length) loop
Node := Container.Last;
Delete_Node (Container, Node);
end loop;
end Delete_Last;
procedure Delete_Node
(Container : in out List;
Node : in out Node_Access)
is
X : Node_Access := Node;
begin
Node := X.Next;
Container.Length := Container.Length - 1;
if X = Container.First then
Container.First := X.Next;
if X = Container.Last then
pragma Assert (Container.First = null);
pragma Assert (Container.Length = 0);
Container.Last := null;
else
pragma Assert (Container.Length > 0);
Container.First.Prev := null;
end if;
elsif X = Container.Last then
pragma Assert (Container.Length > 0);
Container.Last := X.Prev;
Container.Last.Next := null;
else
pragma Assert (Container.Length > 0);
X.Next.Prev := X.Prev;
X.Prev.Next := X.Next;
end if;
Free (X.Element);
Free (X);
end Delete_Node;
function Element (Position : Cursor) return Element_Type is
begin
return Position.Node.Element.all;
end Element;
function 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.First;
elsif Position.Container /= List_Access'(Container'Unchecked_Access) then
raise Program_Error;
end if;
while Node /= null loop
if Node.Element /= null
and then Node.Element.all = Item
then
return Cursor'(Container'Unchecked_Access, Node);
end if;
Node := Node.Next;
end loop;
return No_Element;
end Find;
function First (Container : List) return Cursor is
begin
if Container.First = null then
return No_Element;
end if;
return Cursor'(Container'Unchecked_Access, Container.First);
end First;
function First_Element (Container : List) return Element_Type is
begin
return Container.First.Element.all;
end First_Element;
procedure Generic_Merge
(Target : in out List;
Source : in out List)
is
LI : Cursor;
RI : Cursor;
begin
if Target'Address = Source'Address then
return;
end if;
LI := First (Target);
RI := First (Source);
while RI.Node /= null loop
if LI.Node = null then
Splice (Target, No_Element, Source);
return;
end if;
if LI.Node.Element = null then
LI.Node := LI.Node.Next;
elsif RI.Node.Element = null
or else RI.Node.Element.all < LI.Node.Element.all
then
declare
RJ : constant Cursor := RI;
begin
RI.Node := RI.Node.Next;
Splice (Target, LI, Source, RJ);
end;
else
LI.Node := LI.Node.Next;
end if;
end loop;
end Generic_Merge;
procedure Generic_Sort (Container : in out List) is
procedure Partition (Pivot : Node_Access; Back : Node_Access);
procedure Sort (Front, Back : Node_Access);
procedure Partition (Pivot : Node_Access; Back : Node_Access) is
Node : Node_Access := Pivot.Next;
begin
while Node /= Back loop
if Pivot.Element = null then
Node := Node.Next;
elsif Node.Element = null
or else Node.Element.all < Pivot.Element.all
then
declare
Prev : constant Node_Access := Node.Prev;
Next : constant Node_Access := Node.Next;
begin
Prev.Next := Next;
if Next = null then
Container.Last := Prev;
else
Next.Prev := Prev;
end if;
Node.Next := Pivot;
Node.Prev := Pivot.Prev;
Pivot.Prev := Node;
if Node.Prev = null then
Container.First := Node;
else
Node.Prev.Next := Node;
end if;
Node := Next;
end;
else
Node := Node.Next;
end if;
end loop;
end Partition;
procedure Sort (Front, Back : Node_Access) is
Pivot : Node_Access;
begin
if Front = null then
Pivot := Container.First;
else
Pivot := Front.Next;
end if;
if Pivot /= Back then
Partition (Pivot, Back);
Sort (Front, Pivot);
Sort (Pivot, Back);
end if;
end Sort;
begin
Sort (Front => null, Back => null);
pragma Assert (Container.Length = 0
or else (Container.First.Prev = null
and Container.Last.Next = null));
end Generic_Sort;
function Has_Element (Position : Cursor) return Boolean is
begin
return Position.Container /= null and then Position.Node /= null;
end Has_Element;
procedure Insert
(Container : in out List;
Before : Cursor;
New_Item : Element_Type;
Position : out Cursor;
Count : Count_Type := 1)
is
New_Node : Node_Access;
begin
if Before.Container /= null
and then Before.Container /= List_Access'(Container'Unchecked_Access)
then
raise Program_Error;
end if;
if Count = 0 then
Position := Before;
return;
end if;
declare
Element : Element_Access := new Element_Type'(New_Item);
begin
New_Node := new Node_Type'(Element, null, null);
exception
when others =>
Free (Element);
raise;
end;
Insert_Internal (Container, Before.Node, New_Node);
Position := Cursor'(Before.Container, New_Node);
for J in Count_Type'(2) .. Count loop
declare
Element : Element_Access := new Element_Type'(New_Item);
begin
New_Node := new Node_Type'(Element, null, null);
exception
when others =>
Free (Element);
raise;
end;
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;
begin
Insert (Container, Before, New_Item, Position, Count);
end Insert;
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;
function Is_Empty (Container : List) return Boolean is
begin
return Container.Length = 0;
end Is_Empty;
procedure Iterate
(Container : List;
Process : not null access procedure (Position : in Cursor))
is
Node : Node_Access := Container.First;
begin
while Node /= null loop
Process (Cursor'(Container'Unchecked_Access, Node));
Node := Node.Next;
end loop;
end Iterate;
procedure Move (Target : in out List; Source : in out List) is
begin
if Target'Address = Source'Address then
return;
end if;
if Target.Length > 0 then
raise Constraint_Error;
end if;
Target.First := Source.First;
Source.First := null;
Target.Last := Source.Last;
Source.Last := null;
Target.Length := Source.Length;
Source.Length := 0;
end Move;
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;
function Last_Element (Container : List) return Element_Type is
begin
return Container.Last.Element.all;
end Last_Element;
function Length (Container : List) return Count_Type is
begin
return Container.Length;
end Length;
procedure Next (Position : in out Cursor) is
begin
if Position.Node = null then
return;
end if;
Position.Node := Position.Node.Next;
if Position.Node = null then
Position.Container := null;
end if;
end Next;
function Next (Position : Cursor) return Cursor is
begin
if Position.Node = null then
return No_Element;
end if;
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;
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;
procedure Previous (Position : in out Cursor) is
begin
if Position.Node = null then
return;
end if;
Position.Node := Position.Node.Prev;
if Position.Node = null then
Position.Container := null;
end if;
end Previous;
function Previous (Position : Cursor) return Cursor is
begin
if Position.Node = null then
return No_Element;
end if;
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;
procedure Query_Element
(Position : Cursor;
Process : not null access procedure (Element : in Element_Type))
is
begin
Process (Position.Node.Element.all);
end Query_Element;
procedure Read
(Stream : 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
X.Element := new Element_Type'(Element_Type'Input (Stream));
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
X.Element := new Element_Type'(Element_Type'Input (Stream));
exception
when others =>
Free (X);
raise;
end;
X.Prev := Item.Last;
Item.Last.Next := X;
Item.Last := X;
end loop;
end Read;
procedure Replace_Element
(Position : Cursor;
By : Element_Type)
is
X : Element_Access := Position.Node.Element;
begin
Position.Node.Element := new Element_Type'(By);
Free (X);
end Replace_Element;
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;
elsif Position.Container /= List_Access'(Container'Unchecked_Access) then
raise Program_Error;
end if;
while Node /= null loop
if Node.Element /= null
and then Node.Element.all = Item
then
return Cursor'(Container'Unchecked_Access, Node);
end if;
Node := Node.Prev;
end loop;
return No_Element;
end Reverse_Find;
procedure Reverse_Iterate
(Container : List;
Process : not null access procedure (Position : in Cursor))
is
Node : Node_Access := Container.Last;
begin
while Node /= null loop
Process (Cursor'(Container'Unchecked_Access, Node));
Node := Node.Prev;
end loop;
end Reverse_Iterate;
procedure Reverse_List (Container : in out List) is
I : Node_Access := Container.First;
J : Node_Access := Container.Last;
procedure Swap (L, R : Node_Access);
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;
begin
if Container.Length <= 1 then
return;
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_List;
procedure Splice
(Target : in out List;
Before : Cursor;
Source : in out List)
is
begin
if Before.Container /= null
and then Before.Container /= List_Access'(Target'Unchecked_Access)
then
raise Program_Error;
end if;
if Target'Address = Source'Address
or else Source.Length = 0
then
return;
end if;
if Target.Length = 0 then
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
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
(Target : in out List;
Before : Cursor;
Position : Cursor)
is
X : Node_Access := Position.Node;
begin
if Before.Container /= null
and then Before.Container /= List_Access'(Target'Unchecked_Access)
then
raise Program_Error;
end if;
if Position.Container /= null
and then Position.Container /= List_Access'(Target'Unchecked_Access)
then
raise Program_Error;
end if;
if X = null
or else X = Before.Node
or else X.Next = Before.Node
then
return;
end if;
pragma Assert (Target.Length > 0);
if Before.Node = null then
pragma Assert (X /= Target.Last);
if X = Target.First then
Target.First := X.Next;
Target.First.Prev := null;
else
X.Prev.Next := X.Next;
X.Next.Prev := X.Prev;
end if;
Target.Last.Next := X;
X.Prev := Target.Last;
Target.Last := X;
Target.Last.Next := null;
return;
end if;
if Before.Node = Target.First then
pragma Assert (X /= Target.First);
if X = Target.Last then
Target.Last := X.Prev;
Target.Last.Next := null;
else
X.Prev.Next := X.Next;
X.Next.Prev := X.Prev;
end if;
Target.First.Prev := X;
X.Next := Target.First;
Target.First := X;
Target.First.Prev := null;
return;
end if;
if X = Target.First then
Target.First := X.Next;
Target.First.Prev := null;
elsif X = Target.Last then
Target.Last := X.Prev;
Target.Last.Next := null;
else
X.Prev.Next := X.Next;
X.Next.Prev := X.Prev;
end if;
Before.Node.Prev.Next := X;
X.Prev := Before.Node.Prev;
Before.Node.Prev := X;
X.Next := Before.Node;
end Splice;
procedure Splice
(Target : in out List;
Before : Cursor;
Source : in out List;
Position : Cursor)
is
X : Node_Access := Position.Node;
begin
if Target'Address = Source'Address then
Splice (Target, Before, Position);
return;
end if;
if Before.Container /= null
and then Before.Container /= List_Access'(Target'Unchecked_Access)
then
raise Program_Error;
end if;
if Position.Container /= null
and then Position.Container /= List_Access'(Source'Unchecked_Access)
then
raise Program_Error;
end if;
if X = null then
return;
end if;
pragma Assert (Source.Length > 0);
pragma Assert (Source.First.Prev = null);
pragma Assert (Source.Last.Next = null);
if X = Source.First then
Source.First := X.Next;
Source.First.Prev := null;
if X = Source.Last then
pragma Assert (Source.First = null);
pragma Assert (Source.Length = 1);
Source.Last := null;
end if;
elsif X = Source.Last then
Source.Last := X.Prev;
Source.Last.Next := null;
else
X.Prev.Next := X.Next;
X.Next.Prev := X.Prev;
end if;
if Target.Length = 0 then
pragma Assert (Before = No_Element);
pragma Assert (Target.First = null);
pragma Assert (Target.Last = null);
Target.First := X;
Target.Last := X;
elsif Before.Node = null then
Target.Last.Next := X;
X.Next := Target.Last;
Target.Last := X;
Target.Last.Next := null;
elsif Before.Node = Target.First then
Target.First.Prev := X;
X.Next := Target.First;
Target.First := X;
Target.First.Prev := null;
else
Before.Node.Prev.Next := X;
X.Prev := Before.Node.Prev;
Before.Node.Prev := X;
X.Next := Before.Node;
end if;
Target.Length := Target.Length + 1;
Source.Length := Source.Length - 1;
end Splice;
procedure Swap (I, J : Cursor) is
EI : constant Element_Access := I.Node.Element;
begin
I.Node.Element := J.Node.Element;
J.Node.Element := EI;
end Swap;
procedure Swap_Links
(Container : in out List;
I, J : Cursor)
is
begin
if I = No_Element
or else J = No_Element
then
raise Constraint_Error;
end if;
if I.Container /= List_Access'(Container'Unchecked_Access) then
raise Program_Error;
end if;
if J.Container /= I.Container then
raise Program_Error;
end if;
pragma Assert (Container.Length >= 1);
if I.Node = J.Node then
return;
end if;
pragma Assert (Container.Length >= 2);
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;
procedure Update_Element
(Position : Cursor;
Process : not null access procedure (Element : in out Element_Type))
is
begin
Process (Position.Node.Element.all);
end Update_Element;
procedure Write
(Stream : 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'Output (Stream, Node.Element.all); Node := Node.Next;
end loop;
end Write;
end Ada.Containers.Indefinite_Doubly_Linked_Lists;