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------------------------------------------------------------------------------
-- --
-- GNAT LIBRARY COMPONENTS --
-- --
-- ADA.CONTAINERS.FORMAL_INDEFINITE_VECTORS --
-- --
-- B o d y --
-- --
-- Copyright (C) 2010-2022, 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 Ada.Containers.Generic_Array_Sort;
with Ada.Unchecked_Deallocation;
with System; use type System.Address;
package body Ada.Containers.Formal_Indefinite_Vectors with
SPARK_Mode => Off
is
function H (New_Item : Element_Type) return Holder renames To_Holder;
function E (Container : Holder) return Element_Type renames Get;
Growth_Factor : constant := 2;
-- When growing a container, multiply current capacity by this. Doubling
-- leads to amortized linear-time copying.
subtype Int is Long_Long_Integer;
procedure Free is
new Ada.Unchecked_Deallocation (Elements_Array, Elements_Array_Ptr);
type Maximal_Array_Ptr is access all Elements_Array (Array_Index)
with Storage_Size => 0;
type Maximal_Array_Ptr_Const is access constant Elements_Array (Array_Index)
with Storage_Size => 0;
function Elems (Container : in out Vector) return Maximal_Array_Ptr;
function Elemsc
(Container : Vector) return Maximal_Array_Ptr_Const;
-- Returns a pointer to the Elements array currently in use -- either
-- Container.Elements_Ptr or a pointer to Container.Elements. We work with
-- pointers to a bogus array subtype that is constrained with the maximum
-- possible bounds. This means that the pointer is a thin pointer. This is
-- necessary because 'Unrestricted_Access doesn't work when it produces
-- access-to-unconstrained and is returned from a function.
--
-- Note that this is dangerous: make sure calls to this use an indexed
-- component or slice that is within the bounds 1 .. Length (Container).
function Get_Element
(Container : Vector;
Position : Capacity_Range) return Element_Type;
function To_Array_Index (Index : Index_Type'Base) return Count_Type'Base;
function Current_Capacity (Container : Vector) return Capacity_Range;
procedure Insert_Space
(Container : in out Vector;
Before : Extended_Index;
Count : Count_Type := 1);
---------
-- "=" --
---------
function "=" (Left : Vector; Right : Vector) return Boolean is
begin
if Left'Address = Right'Address then
return True;
end if;
if Length (Left) /= Length (Right) then
return False;
end if;
for J in 1 .. Length (Left) loop
if Get_Element (Left, J) /= Get_Element (Right, J) then
return False;
end if;
end loop;
return True;
end "=";
------------
-- Append --
------------
procedure Append (Container : in out Vector; New_Item : Vector) is
begin
if Is_Empty (New_Item) then
return;
end if;
if Container.Last >= Index_Type'Last then
raise Constraint_Error with "vector is already at its maximum length";
end if;
Insert (Container, Container.Last + 1, New_Item);
end Append;
procedure Append (Container : in out Vector; New_Item : Element_Type) is
begin
Append (Container, New_Item, 1);
end Append;
procedure Append
(Container : in out Vector;
New_Item : Element_Type;
Count : Count_Type)
is
begin
if Count = 0 then
return;
end if;
if Container.Last >= Index_Type'Last then
raise Constraint_Error with "vector is already at its maximum length";
end if;
Insert (Container, Container.Last + 1, New_Item, Count);
end Append;
------------
-- Assign --
------------
procedure Assign (Target : in out Vector; Source : Vector) is
LS : constant Capacity_Range := Length (Source);
begin
if Target'Address = Source'Address then
return;
end if;
if Bounded and then Target.Capacity < LS then
raise Constraint_Error;
end if;
Clear (Target);
Append (Target, Source);
end Assign;
--------------
-- Capacity --
--------------
function Capacity (Container : Vector) return Capacity_Range is
begin
return
(if Bounded then
Container.Capacity
else
Capacity_Range'Last);
end Capacity;
-----------
-- Clear --
-----------
procedure Clear (Container : in out Vector) is
begin
Container.Last := No_Index;
-- Free element, note that this is OK if Elements_Ptr is null
Free (Container.Elements_Ptr);
end Clear;
------------------------
-- Constant_Reference --
------------------------
function Constant_Reference
(Container : aliased Vector;
Index : Index_Type) return not null access constant Element_Type
is
begin
if Index > Container.Last then
raise Constraint_Error with "Index is out of range";
end if;
declare
II : constant Int'Base := Int (Index) - Int (No_Index);
I : constant Capacity_Range := Capacity_Range (II);
begin
return Constant_Reference (Elemsc (Container) (I));
end;
end Constant_Reference;
--------------
-- Contains --
--------------
function Contains
(Container : Vector;
Item : Element_Type) return Boolean
is
begin
return Find_Index (Container, Item) /= No_Index;
end Contains;
----------
-- Copy --
----------
function Copy
(Source : Vector;
Capacity : Capacity_Range := 0) return Vector
is
LS : constant Capacity_Range := Length (Source);
C : Capacity_Range;
begin
if Capacity = 0 then
C := LS;
elsif Capacity >= LS then
C := Capacity;
else
raise Capacity_Error;
end if;
return Target : Vector (C) do
Elems (Target) (1 .. LS) := Elemsc (Source) (1 .. LS);
Target.Last := Source.Last;
end return;
end Copy;
----------------------
-- Current_Capacity --
----------------------
function Current_Capacity (Container : Vector) return Capacity_Range is
begin
return
(if Container.Elements_Ptr = null then
Container.Elements'Length
else
Container.Elements_Ptr.all'Length);
end Current_Capacity;
------------
-- Delete --
------------
procedure Delete (Container : in out Vector; Index : Extended_Index) is
begin
Delete (Container, Index, 1);
end Delete;
procedure Delete
(Container : in out Vector;
Index : Extended_Index;
Count : Count_Type)
is
Old_Last : constant Index_Type'Base := Container.Last;
Old_Len : constant Count_Type := Length (Container);
New_Last : Index_Type'Base;
Count2 : Count_Type'Base; -- count of items from Index to Old_Last
Off : Count_Type'Base; -- Index expressed as offset from IT'First
begin
-- Delete removes items from the vector, the number of which is the
-- minimum of the specified Count and the items (if any) that exist from
-- Index to Container.Last. There are no constraints on the specified
-- value of Count (it can be larger than what's available at this
-- position in the vector, for example), but there are constraints on
-- the allowed values of the Index.
-- As a precondition on the generic actual Index_Type, the base type
-- must include Index_Type'Pred (Index_Type'First); this is the value
-- that Container.Last assumes when the vector is empty. However, we do
-- not allow that as the value for Index when specifying which items
-- should be deleted, so we must manually check. (That the user is
-- allowed to specify the value at all here is a consequence of the
-- declaration of the Extended_Index subtype, which includes the values
-- in the base range that immediately precede and immediately follow the
-- values in the Index_Type.)
if Index < Index_Type'First then
raise Constraint_Error with "Index is out of range (too small)";
end if;
-- We do allow a value greater than Container.Last to be specified as
-- the Index, but only if it's immediately greater. This allows the
-- corner case of deleting no items from the back end of the vector to
-- be treated as a no-op. (It is assumed that specifying an index value
-- greater than Last + 1 indicates some deeper flaw in the caller's
-- algorithm, so that case is treated as a proper error.)
if Index > Old_Last then
if Index > Old_Last + 1 then
raise Constraint_Error with "Index is out of range (too large)";
end if;
return;
end if;
if Count = 0 then
return;
end if;
-- We first calculate what's available for deletion starting at
-- Index. Here and elsewhere we use the wider of Index_Type'Base and
-- Count_Type'Base as the type for intermediate values. (See function
-- Length for more information.)
if Count_Type'Base'Last >= Index_Type'Pos (Index_Type'Base'Last) then
Count2 := Count_Type'Base (Old_Last) - Count_Type'Base (Index) + 1;
else
Count2 := Count_Type'Base (Old_Last - Index + 1);
end if;
-- If more elements are requested (Count) for deletion than are
-- available (Count2) for deletion beginning at Index, then everything
-- from Index is deleted. There are no elements to slide down, and so
-- all we need to do is set the value of Container.Last.
if Count >= Count2 then
Container.Last := Index - 1;
return;
end if;
-- There are some elements that aren't being deleted (the requested
-- count was less than the available count), so we must slide them down
-- to Index. We first calculate the index values of the respective array
-- slices, using the wider of Index_Type'Base and Count_Type'Base as the
-- type for intermediate calculations.
if Index_Type'Base'Last >= Count_Type'Pos (Count_Type'Last) then
Off := Count_Type'Base (Index - Index_Type'First);
New_Last := Old_Last - Index_Type'Base (Count);
else
Off := Count_Type'Base (Index) - Count_Type'Base (Index_Type'First);
New_Last := Index_Type'Base (Count_Type'Base (Old_Last) - Count);
end if;
-- The array index values for each slice have already been determined,
-- so we just slide down to Index the elements that weren't deleted.
declare
EA : Maximal_Array_Ptr renames Elems (Container);
Idx : constant Count_Type := EA'First + Off;
begin
EA (Idx .. Old_Len - Count) := EA (Idx + Count .. Old_Len);
Container.Last := New_Last;
end;
end Delete;
------------------
-- Delete_First --
------------------
procedure Delete_First (Container : in out Vector) is
begin
Delete_First (Container, 1);
end Delete_First;
procedure Delete_First (Container : in out Vector; Count : Count_Type) is
begin
if Count = 0 then
return;
elsif Count >= Length (Container) then
Clear (Container);
return;
else
Delete (Container, Index_Type'First, Count);
end if;
end Delete_First;
-----------------
-- Delete_Last --
-----------------
procedure Delete_Last (Container : in out Vector) is
begin
Delete_Last (Container, 1);
end Delete_Last;
procedure Delete_Last (Container : in out Vector; Count : Count_Type) is
begin
if Count = 0 then
return;
end if;
-- There is no restriction on how large Count can be when deleting
-- items. If it is equal or greater than the current length, then this
-- is equivalent to clearing the vector. (In particular, there's no need
-- for us to actually calculate the new value for Last.)
-- If the requested count is less than the current length, then we must
-- calculate the new value for Last. For the type we use the widest of
-- Index_Type'Base and Count_Type'Base for the intermediate values of
-- our calculation. (See the comments in Length for more information.)
if Count >= Length (Container) then
Container.Last := No_Index;
elsif Index_Type'Base'Last >= Count_Type'Pos (Count_Type'Last) then
Container.Last := Container.Last - Index_Type'Base (Count);
else
Container.Last :=
Index_Type'Base (Count_Type'Base (Container.Last) - Count);
end if;
end Delete_Last;
-------------
-- Element --
-------------
function Element
(Container : Vector;
Index : Index_Type) return Element_Type
is
begin
if Index > Container.Last then
raise Constraint_Error with "Index is out of range";
end if;
declare
II : constant Int'Base := Int (Index) - Int (No_Index);
I : constant Capacity_Range := Capacity_Range (II);
begin
return Get_Element (Container, I);
end;
end Element;
-----------
-- Elems --
-----------
function Elems (Container : in out Vector) return Maximal_Array_Ptr is
begin
return
(if Container.Elements_Ptr = null then
Container.Elements'Unrestricted_Access
else
Container.Elements_Ptr.all'Unrestricted_Access);
end Elems;
function Elemsc (Container : Vector) return Maximal_Array_Ptr_Const is
begin
return
(if Container.Elements_Ptr = null then
Container.Elements'Unrestricted_Access
else
Container.Elements_Ptr.all'Unrestricted_Access);
end Elemsc;
----------------
-- Find_Index --
----------------
function Find_Index
(Container : Vector;
Item : Element_Type;
Index : Index_Type := Index_Type'First) return Extended_Index
is
K : Count_Type;
Last : constant Extended_Index := Last_Index (Container);
begin
K := Capacity_Range (Int (Index) - Int (No_Index));
for Indx in Index .. Last loop
if Get_Element (Container, K) = Item then
return Indx;
end if;
K := K + 1;
end loop;
return No_Index;
end Find_Index;
-------------------
-- First_Element --
-------------------
function First_Element (Container : Vector) return Element_Type is
begin
if Is_Empty (Container) then
raise Constraint_Error with "Container is empty";
else
return Get_Element (Container, 1);
end if;
end First_Element;
-----------------
-- First_Index --
-----------------
function First_Index (Container : Vector) return Index_Type is
pragma Unreferenced (Container);
begin
return Index_Type'First;
end First_Index;
------------------
-- Formal_Model --
------------------
package body Formal_Model is
-------------------------
-- M_Elements_In_Union --
-------------------------
function M_Elements_In_Union
(Container : M.Sequence;
Left : M.Sequence;
Right : M.Sequence) return Boolean
is
begin
for Index in Index_Type'First .. M.Last (Container) loop
declare
Elem : constant Element_Type := Element (Container, Index);
begin
if not M.Contains (Left, Index_Type'First, M.Last (Left), Elem)
and then
not M.Contains
(Right, Index_Type'First, M.Last (Right), Elem)
then
return False;
end if;
end;
end loop;
return True;
end M_Elements_In_Union;
-------------------------
-- M_Elements_Included --
-------------------------
function M_Elements_Included
(Left : M.Sequence;
L_Fst : Index_Type := Index_Type'First;
L_Lst : Extended_Index;
Right : M.Sequence;
R_Fst : Index_Type := Index_Type'First;
R_Lst : Extended_Index) return Boolean
is
begin
for I in L_Fst .. L_Lst loop
declare
Found : Boolean := False;
J : Extended_Index := R_Fst - 1;
begin
while not Found and J < R_Lst loop
J := J + 1;
if Element (Left, I) = Element (Right, J) then
Found := True;
end if;
end loop;
if not Found then
return False;
end if;
end;
end loop;
return True;
end M_Elements_Included;
-------------------------
-- M_Elements_Reversed --
-------------------------
function M_Elements_Reversed
(Left : M.Sequence;
Right : M.Sequence) return Boolean
is
L : constant Index_Type := M.Last (Left);
begin
if L /= M.Last (Right) then
return False;
end if;
for I in Index_Type'First .. L loop
if Element (Left, I) /= Element (Right, L - I + 1)
then
return False;
end if;
end loop;
return True;
end M_Elements_Reversed;
------------------------
-- M_Elements_Swapped --
------------------------
function M_Elements_Swapped
(Left : M.Sequence;
Right : M.Sequence;
X : Index_Type;
Y : Index_Type) return Boolean
is
begin
if M.Length (Left) /= M.Length (Right)
or else Element (Left, X) /= Element (Right, Y)
or else Element (Left, Y) /= Element (Right, X)
then
return False;
end if;
for I in Index_Type'First .. M.Last (Left) loop
if I /= X and then I /= Y
and then Element (Left, I) /= Element (Right, I)
then
return False;
end if;
end loop;
return True;
end M_Elements_Swapped;
-----------
-- Model --
-----------
function Model (Container : Vector) return M.Sequence is
R : M.Sequence;
begin
for Position in 1 .. Length (Container) loop
R := M.Add (R, E (Elemsc (Container) (Position)));
end loop;
return R;
end Model;
end Formal_Model;
---------------------
-- Generic_Sorting --
---------------------
package body Generic_Sorting with SPARK_Mode => Off is
------------------
-- Formal_Model --
------------------
package body Formal_Model is
-----------------------
-- M_Elements_Sorted --
-----------------------
function M_Elements_Sorted (Container : M.Sequence) return Boolean is
begin
if M.Length (Container) = 0 then
return True;
end if;
declare
E1 : Element_Type := Element (Container, Index_Type'First);
begin
for I in Index_Type'First + 1 .. M.Last (Container) loop
declare
E2 : constant Element_Type := Element (Container, I);
begin
if E2 < E1 then
return False;
end if;
E1 := E2;
end;
end loop;
end;
return True;
end M_Elements_Sorted;
end Formal_Model;
---------------
-- Is_Sorted --
---------------
function Is_Sorted (Container : Vector) return Boolean is
L : constant Capacity_Range := Length (Container);
begin
for J in 1 .. L - 1 loop
if Get_Element (Container, J + 1) < Get_Element (Container, J) then
return False;
end if;
end loop;
return True;
end Is_Sorted;
----------
-- Sort --
----------
procedure Sort (Container : in out Vector) is
function "<" (Left : Holder; Right : Holder) return Boolean is
(E (Left) < E (Right));
procedure Sort is new Generic_Array_Sort
(Index_Type => Array_Index,
Element_Type => Holder,
Array_Type => Elements_Array,
"<" => "<");
Len : constant Capacity_Range := Length (Container);
begin
if Container.Last <= Index_Type'First then
return;
else
Sort (Elems (Container) (1 .. Len));
end if;
end Sort;
-----------
-- Merge --
-----------
procedure Merge (Target : in out Vector; Source : in out Vector) is
I : Count_Type;
J : Count_Type;
begin
if Target'Address = Source'Address then
raise Program_Error with "Target and Source denote same container";
end if;
if Length (Source) = 0 then
return;
end if;
if Length (Target) = 0 then
Move (Target => Target, Source => Source);
return;
end if;
I := Length (Target);
declare
New_Length : constant Count_Type := I + Length (Source);
begin
if not Bounded
and then Current_Capacity (Target) < Capacity_Range (New_Length)
then
Reserve_Capacity
(Target,
Capacity_Range'Max
(Current_Capacity (Target) * Growth_Factor,
Capacity_Range (New_Length)));
end if;
if Index_Type'Base'Last >= Count_Type'Pos (Count_Type'Last) then
Target.Last := No_Index + Index_Type'Base (New_Length);
else
Target.Last :=
Index_Type'Base (Count_Type'Base (No_Index) + New_Length);
end if;
end;
declare
TA : Maximal_Array_Ptr renames Elems (Target);
SA : Maximal_Array_Ptr renames Elems (Source);
begin
J := Length (Target);
while Length (Source) /= 0 loop
if I = 0 then
TA (1 .. J) := SA (1 .. Length (Source));
Source.Last := No_Index;
exit;
end if;
if E (SA (Length (Source))) < E (TA (I)) then
TA (J) := TA (I);
I := I - 1;
else
TA (J) := SA (Length (Source));
Source.Last := Source.Last - 1;
end if;
J := J - 1;
end loop;
end;
end Merge;
end Generic_Sorting;
-----------------
-- Get_Element --
-----------------
function Get_Element
(Container : Vector;
Position : Capacity_Range) return Element_Type
is
begin
return E (Elemsc (Container) (Position));
end Get_Element;
-----------------
-- Has_Element --
-----------------
function Has_Element
(Container : Vector;
Position : Extended_Index) return Boolean
is
begin
return Position in First_Index (Container) .. Last_Index (Container);
end Has_Element;
------------
-- Insert --
------------
procedure Insert
(Container : in out Vector;
Before : Extended_Index;
New_Item : Element_Type)
is
begin
Insert (Container, Before, New_Item, 1);
end Insert;
procedure Insert
(Container : in out Vector;
Before : Extended_Index;
New_Item : Element_Type;
Count : Count_Type)
is
J : Count_Type'Base; -- scratch
begin
-- Use Insert_Space to create the "hole" (the destination slice)
Insert_Space (Container, Before, Count);
J := To_Array_Index (Before);
Elems (Container) (J .. J - 1 + Count) := [others => H (New_Item)];
end Insert;
procedure Insert
(Container : in out Vector;
Before : Extended_Index;
New_Item : Vector)
is
N : constant Count_Type := Length (New_Item);
B : Count_Type; -- index Before converted to Count_Type
begin
if Container'Address = New_Item'Address then
raise Program_Error with
"Container and New_Item denote same container";
end if;
-- Use Insert_Space to create the "hole" (the destination slice) into
-- which we copy the source items.
Insert_Space (Container, Before, Count => N);
if N = 0 then
-- There's nothing else to do here (vetting of parameters was
-- performed already in Insert_Space), so we simply return.
return;
end if;
B := To_Array_Index (Before);
Elems (Container) (B .. B + N - 1) := Elemsc (New_Item) (1 .. N);
end Insert;
------------------
-- Insert_Space --
------------------
procedure Insert_Space
(Container : in out Vector;
Before : Extended_Index;
Count : Count_Type := 1)
is
Old_Length : constant Count_Type := Length (Container);
Max_Length : Count_Type'Base; -- determined from range of Index_Type
New_Length : Count_Type'Base; -- sum of current length and Count
Index : Index_Type'Base; -- scratch for intermediate values
J : Count_Type'Base; -- scratch
begin
-- As a precondition on the generic actual Index_Type, the base type
-- must include Index_Type'Pred (Index_Type'First); this is the value
-- that Container.Last assumes when the vector is empty. However, we do
-- not allow that as the value for Index when specifying where the new
-- items should be inserted, so we must manually check. (That the user
-- is allowed to specify the value at all here is a consequence of the
-- declaration of the Extended_Index subtype, which includes the values
-- in the base range that immediately precede and immediately follow the
-- values in the Index_Type.)
if Before < Index_Type'First then
raise Constraint_Error with
"Before index is out of range (too small)";
end if;
-- We do allow a value greater than Container.Last to be specified as
-- the Index, but only if it's immediately greater. This allows for the
-- case of appending items to the back end of the vector. (It is assumed
-- that specifying an index value greater than Last + 1 indicates some
-- deeper flaw in the caller's algorithm, so that case is treated as a
-- proper error.)
if Before > Container.Last
and then Before - 1 > Container.Last
then
raise Constraint_Error with
"Before index is out of range (too large)";
end if;
-- We treat inserting 0 items into the container as a no-op, so we
-- simply return.
if Count = 0 then
return;
end if;
-- There are two constraints we need to satisfy. The first constraint is
-- that a container cannot have more than Count_Type'Last elements, so
-- we must check the sum of the current length and the insertion
-- count. Note that we cannot simply add these values, because of the
-- possibility of overflow.
if Old_Length > Count_Type'Last - Count then
raise Constraint_Error with "Count is out of range";
end if;
-- It is now safe compute the length of the new vector, without fear of
-- overflow.
New_Length := Old_Length + Count;
-- The second constraint is that the new Last index value cannot exceed
-- Index_Type'Last. In each branch below, we calculate the maximum
-- length (computed from the range of values in Index_Type), and then
-- compare the new length to the maximum length. If the new length is
-- acceptable, then we compute the new last index from that.
if Index_Type'Base'Last >= Count_Type'Pos (Count_Type'Last) then
-- We have to handle the case when there might be more values in the
-- range of Index_Type than in the range of Count_Type.
if Index_Type'First <= 0 then
-- We know that No_Index (the same as Index_Type'First - 1) is
-- less than 0, so it is safe to compute the following sum without
-- fear of overflow.
Index := No_Index + Index_Type'Base (Count_Type'Last);
if Index <= Index_Type'Last then
-- We have determined that range of Index_Type has at least as
-- many values as in Count_Type, so Count_Type'Last is the
-- maximum number of items that are allowed.
Max_Length := Count_Type'Last;
else
-- The range of Index_Type has fewer values than in Count_Type,
-- so the maximum number of items is computed from the range of
-- the Index_Type.
Max_Length := Count_Type'Base (Index_Type'Last - No_Index);
end if;
else
-- No_Index is equal or greater than 0, so we can safely compute
-- the difference without fear of overflow (which we would have to
-- worry about if No_Index were less than 0, but that case is
-- handled above).
if Index_Type'Last - No_Index >= Count_Type'Pos (Count_Type'Last)
then
-- We have determined that range of Index_Type has at least as
-- many values as in Count_Type, so Count_Type'Last is the
-- maximum number of items that are allowed.
Max_Length := Count_Type'Last;
else
-- The range of Index_Type has fewer values than in Count_Type,
-- so the maximum number of items is computed from the range of
-- the Index_Type.
Max_Length := Count_Type'Base (Index_Type'Last - No_Index);
end if;
end if;
elsif Index_Type'First <= 0 then
-- We know that No_Index (the same as Index_Type'First - 1) is less
-- than 0, so it is safe to compute the following sum without fear of
-- overflow.
J := Count_Type'Base (No_Index) + Count_Type'Last;
if J <= Count_Type'Base (Index_Type'Last) then
-- We have determined that range of Index_Type has at least as
-- many values as in Count_Type, so Count_Type'Last is the maximum
-- number of items that are allowed.
Max_Length := Count_Type'Last;
else
-- The range of Index_Type has fewer values than Count_Type does,
-- so the maximum number of items is computed from the range of
-- the Index_Type.
Max_Length :=
Count_Type'Base (Index_Type'Last) - Count_Type'Base (No_Index);
end if;
else
-- No_Index is equal or greater than 0, so we can safely compute the
-- difference without fear of overflow (which we would have to worry
-- about if No_Index were less than 0, but that case is handled
-- above).
Max_Length :=
Count_Type'Base (Index_Type'Last) - Count_Type'Base (No_Index);
end if;
-- We have just computed the maximum length (number of items). We must
-- now compare the requested length to the maximum length, as we do not
-- allow a vector expand beyond the maximum (because that would create
-- an internal array with a last index value greater than
-- Index_Type'Last, with no way to index those elements).
if New_Length > Max_Length then
raise Constraint_Error with "Count is out of range";
end if;
J := To_Array_Index (Before);
-- Increase the capacity of container if needed
if not Bounded
and then Current_Capacity (Container) < Capacity_Range (New_Length)
then
Reserve_Capacity
(Container,
Capacity_Range'Max
(Current_Capacity (Container) * Growth_Factor,
Capacity_Range (New_Length)));
end if;
declare
EA : Maximal_Array_Ptr renames Elems (Container);
begin
if Before <= Container.Last then
-- The new items are being inserted before some existing
-- elements, so we must slide the existing elements up to their
-- new home.
EA (J + Count .. New_Length) := EA (J .. Old_Length);
end if;
end;
if Index_Type'Base'Last >= Count_Type'Pos (Count_Type'Last) then
Container.Last := No_Index + Index_Type'Base (New_Length);
else
Container.Last :=
Index_Type'Base (Count_Type'Base (No_Index) + New_Length);
end if;
end Insert_Space;
--------------
-- Is_Empty --
--------------
function Is_Empty (Container : Vector) return Boolean is
begin
return Last_Index (Container) < Index_Type'First;
end Is_Empty;
------------------
-- Last_Element --
------------------
function Last_Element (Container : Vector) return Element_Type is
begin
if Is_Empty (Container) then
raise Constraint_Error with "Container is empty";
else
return Get_Element (Container, Length (Container));
end if;
end Last_Element;
----------------
-- Last_Index --
----------------
function Last_Index (Container : Vector) return Extended_Index is
begin
return Container.Last;
end Last_Index;
------------
-- Length --
------------
function Length (Container : Vector) return Capacity_Range is
L : constant Int := Int (Container.Last);
F : constant Int := Int (Index_Type'First);
N : constant Int'Base := L - F + 1;
begin
return Capacity_Range (N);
end Length;
----------
-- Move --
----------
procedure Move (Target : in out Vector; Source : in out Vector) is
LS : constant Capacity_Range := Length (Source);
begin
if Target'Address = Source'Address then
return;
end if;
if Bounded and then Target.Capacity < LS then
raise Constraint_Error;
end if;
Clear (Target);
Append (Target, Source);
Clear (Source);
end Move;
------------
-- Prepend --
------------
procedure Prepend (Container : in out Vector; New_Item : Vector) is
begin
Insert (Container, Index_Type'First, New_Item);
end Prepend;
procedure Prepend (Container : in out Vector; New_Item : Element_Type) is
begin
Prepend (Container, New_Item, 1);
end Prepend;
procedure Prepend
(Container : in out Vector;
New_Item : Element_Type;
Count : Count_Type)
is
begin
Insert (Container, Index_Type'First, New_Item, Count);
end Prepend;
---------------
-- Reference --
---------------
function Reference
(Container : not null access Vector;
Index : Index_Type) return not null access Element_Type
is
begin
if Index > Container.Last then
raise Constraint_Error with "Index is out of range";
end if;
declare
II : constant Int'Base := Int (Index) - Int (No_Index);
I : constant Capacity_Range := Capacity_Range (II);
begin
if Container.Elements_Ptr = null then
return Reference (Container.Elements (I)'Access);
else
return Reference (Container.Elements_Ptr (I)'Access);
end if;
end;
end Reference;
---------------------
-- Replace_Element --
---------------------
procedure Replace_Element
(Container : in out Vector;
Index : Index_Type;
New_Item : Element_Type)
is
begin
if Index > Container.Last then
raise Constraint_Error with "Index is out of range";
end if;
declare
II : constant Int'Base := Int (Index) - Int (No_Index);
I : constant Capacity_Range := Capacity_Range (II);
begin
Elems (Container) (I) := H (New_Item);
end;
end Replace_Element;
----------------------
-- Reserve_Capacity --
----------------------
procedure Reserve_Capacity
(Container : in out Vector;
Capacity : Capacity_Range)
is
begin
if Bounded then
if Capacity > Container.Capacity then
raise Constraint_Error with "Capacity is out of range";
end if;
else
if Capacity > Current_Capacity (Container) then
declare
New_Elements : constant Elements_Array_Ptr :=
new Elements_Array (1 .. Capacity);
L : constant Capacity_Range := Length (Container);
begin
New_Elements (1 .. L) := Elemsc (Container) (1 .. L);
Free (Container.Elements_Ptr);
Container.Elements_Ptr := New_Elements;
end;
end if;
end if;
end Reserve_Capacity;
----------------------
-- Reverse_Elements --
----------------------
procedure Reverse_Elements (Container : in out Vector) is
begin
if Length (Container) <= 1 then
return;
end if;
declare
I : Capacity_Range;
J : Capacity_Range;
E : Elements_Array renames
Elems (Container) (1 .. Length (Container));
begin
I := 1;
J := Length (Container);
while I < J loop
declare
EI : constant Holder := E (I);
begin
E (I) := E (J);
E (J) := EI;
end;
I := I + 1;
J := J - 1;
end loop;
end;
end Reverse_Elements;
------------------------
-- Reverse_Find_Index --
------------------------
function Reverse_Find_Index
(Container : Vector;
Item : Element_Type;
Index : Index_Type := Index_Type'Last) return Extended_Index
is
Last : Index_Type'Base;
K : Count_Type'Base;
begin
if Index > Last_Index (Container) then
Last := Last_Index (Container);
else
Last := Index;
end if;
K := Capacity_Range (Int (Last) - Int (No_Index));
for Indx in reverse Index_Type'First .. Last loop
if Get_Element (Container, K) = Item then
return Indx;
end if;
K := K - 1;
end loop;
return No_Index;
end Reverse_Find_Index;
----------
-- Swap --
----------
procedure Swap
(Container : in out Vector;
I : Index_Type;
J : Index_Type)
is
begin
if I > Container.Last then
raise Constraint_Error with "I index is out of range";
end if;
if J > Container.Last then
raise Constraint_Error with "J index is out of range";
end if;
if I = J then
return;
end if;
declare
II : constant Int'Base := Int (I) - Int (No_Index);
JJ : constant Int'Base := Int (J) - Int (No_Index);
EI : Holder renames Elems (Container) (Capacity_Range (II));
EJ : Holder renames Elems (Container) (Capacity_Range (JJ));
EI_Copy : constant Holder := EI;
begin
EI := EJ;
EJ := EI_Copy;
end;
end Swap;
--------------------
-- To_Array_Index --
--------------------
function To_Array_Index (Index : Index_Type'Base) return Count_Type'Base is
Offset : Count_Type'Base;
begin
-- We know that
-- Index >= Index_Type'First
-- hence we also know that
-- Index - Index_Type'First >= 0
-- The issue is that even though 0 is guaranteed to be a value in the
-- type Index_Type'Base, there's no guarantee that the difference is a
-- value in that type. To prevent overflow we use the wider of
-- Count_Type'Base and Index_Type'Base to perform intermediate
-- calculations.
if Index_Type'Base'Last >= Count_Type'Pos (Count_Type'Last) then
Offset := Count_Type'Base (Index - Index_Type'First);
else
Offset := Count_Type'Base (Index) -
Count_Type'Base (Index_Type'First);
end if;
-- The array index subtype for all container element arrays always
-- starts with 1.
return 1 + Offset;
end To_Array_Index;
---------------
-- To_Vector --
---------------
function To_Vector
(New_Item : Element_Type;
Length : Capacity_Range) return Vector
is
begin
if Length = 0 then
return Empty_Vector;
end if;
declare
First : constant Int := Int (Index_Type'First);
Last_As_Int : constant Int'Base := First + Int (Length) - 1;
Last : Index_Type;
begin
if Last_As_Int > Index_Type'Pos (Index_Type'Last) then
raise Constraint_Error with "Length is out of range"; -- ???
end if;
Last := Index_Type (Last_As_Int);
return
(Capacity => Length,
Last => Last,
Elements_Ptr => <>,
Elements => [others => H (New_Item)]);
end;
end To_Vector;
end Ada.Containers.Formal_Indefinite_Vectors;