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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- R E S T R I C T --
-- --
-- S p e c --
-- --
-- $Revision: 1.7 $ --
-- --
-- Copyright (C) 1992,1993,1994,1995,1996 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 2, 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. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
-- --
------------------------------------------------------------------------------
-- This package deals with the implementation of the Restrictions pragma
with Types; use Types;
with Uintp; use Uintp;
with Uname; use Uname;
package Restrict is
Any_Restrictions : Boolean := False;
-- Set to True if any restrictions have been processed (used to optimize
-- testing of restrictions to speed up normal case with no restrictions).
-- The following enumeration type defines the set of restriction
-- identifiers that are implemented in GNAT. To add a new restriction
-- identifier, add an entry with the name to be used in the pragma.
type Restriction_Id is (
Immediate_Reclamation, -- (RM H.4(10))
No_Abort_Statements, -- (RM D.7(5), H.4(3))
No_Access_Subprograms, -- (RM H.4(17))
No_Allocators, -- (RM H.4(7))
No_Asynchronous_Control, -- (RM D.9(10))
No_Delay, -- (RM H.4(21))
No_Dispatch, -- (RM H.4(19))
No_Dynamic_Priorities, -- (RM D.9(9))
No_Exceptions, -- (RM H.4(12))
No_Fixed_Point, -- (RM H.4(15))
No_Floating_Point, -- (RM H.4(14))
No_Implementation_Attributes, -- GNAT
No_Implementation_Pragmas, -- GNAT
No_IO, -- (RM H.4(20))
No_Implicit_Heap_Allocations, -- (RM D.8(8), H.4(3))
No_Local_Allocators, -- (RM H.4(8))
No_Nested_Finalization, -- (RM D.7(4))
No_Protected_Types, -- (RM H.4(5))
No_Recursion, -- (RM H.4(22))
No_Reentrancy, -- (RM H.4(23))
No_Task_Allocators, -- (RM D.7(7))
No_Task_Hierarchy, -- (RM D.7(3), H.4(3))
No_Terminate_Alternatives, -- (RM D.7(6))
No_Unchecked_Access, -- (RM H.4(18))
No_Unchecked_Conversion, -- (RM H.4(16))
No_Unchecked_Deallocation, -- (RM H.4(9))
Not_A_Restriction_Id);
-- The following enumeration type defines the set of restriction
-- parameter identifiers that are implemented in GNAT. To add a new
-- restriction parameter identifier, add an entry with the name to be
-- used in the pragma.
-- Note: the GNAT implementation currently only accomodates restriction
-- parameter identifiers whose expression value is a non-negative
-- integer. This is true for all language defined parameters.
type Restriction_Parameter_Id is (
Max_Asynchronous_Select_Nesting, -- (RM D.9(18), H.4(3))
Max_Protected_Entries, -- (RM D.9(14))
Max_Select_Alternatives, -- (RM D.9(12))
Max_Storage_At_Blocking, -- (RM D.9(17))
Max_Task_Entries, -- (RM D.9(13), H.4(3))
Max_Tasks, -- (RM D.9(19), H.4(3))
Not_A_Restriction_Parameter_Id);
-- The following array indicates the setting of restriction identifiers.
-- All values are initially False, and are set True if a Restrictions
-- pragma specifies the corresponding restriction identifier.
type Restrictions_Type is
array (Restriction_Id) of Boolean;
Restrictions_Default :
constant Restrictions_Type := (others => False);
Restrictions :
Restrictions_Type := Restrictions_Default;
-- The following array indicates the setting of restriction parameter
-- identifier values. All values are initially set to -1 indicating that
-- the parameter is not set, and are set to the appropriate non-negative
-- value if a Restrictions pragma specifies the corresponding restriction
-- parameter identifier with an appropriate value.
type Restriction_Parameters_Type is
array (Restriction_Parameter_Id) of Uint;
Restriction_Parameters_Default :
constant Restriction_Parameters_Type := (others => Uint_Minus_1);
Restriction_Parameters :
Restriction_Parameters_Type := Restriction_Parameters_Default;
-- This array defines the mapping between restriction identifiers and
-- predefined language files containing units for which the identifier
-- forbids semantic dependence.
type Unit_Entry is record
Res_Id : Restriction_Id;
Filenm : String (1 .. 6);
end record;
type Unit_Array_Type is array (Positive range <>) of Unit_Entry;
Unit_Array : constant Unit_Array_Type := (
(No_Asynchronous_Control, "astaco"),
(No_Delay, "calend"),
(No_Dynamic_Priorities, "dynpri"),
(No_IO, "direio"),
(No_IO, "sequio"),
(No_IO, "ststio"),
(No_IO, "textio"),
(No_IO, "witeio"),
(No_Unchecked_Conversion, "unccon"),
(No_Unchecked_Deallocation, "uncdea"));
-----------------
-- Subprograms --
-----------------
procedure Check_Restricted_Unit (U : Unit_Name_Type; Loc : Source_Ptr);
-- Checks if loading of unit U is prohibited by the setting of some
-- restriction (e.g. No_IO restricts the loading of unit Ada.Text_IO).
-- If a restriction exists post error message at the given location.
procedure Check_Restriction (R : Restriction_Id; N : Node_Id);
-- Checks that the given restriction is not set, and if it is set, posts
-- an appropriate message is posted on the given node.
procedure Check_Restriction
(R : Restriction_Parameter_Id;
N : Node_Id);
-- Checks that the given restriction parameter identifier is not set to
-- zero. If it is set to zero, then the node N is replaced by a node
-- that raises Storage_Error, and a warning is issued.
procedure Check_Restriction
(R : Restriction_Parameter_Id;
V : Uint;
N : Node_Id);
-- Checks that the count in V does not exceed the maximum value of the
-- restriction parameter value corresponding to the given restriction
-- parameter identifier (if it has been set). If the count in V exceeds
-- the maximum, then post an error message on node N.
function Get_Restriction_Id
(N : Name_Id)
return Restriction_Id;
-- Given an identifier name, determines if it is a valid restriction
-- identifier, and if so returns the corresponding Restriction_Id
-- value, otherwise returns Not_A_Restriction_Id.
function Get_Restriction_Parameter_Id
(N : Name_Id)
return Restriction_Parameter_Id;
-- Given an identifier name, determines if it is a valid restriction
-- parameter identifier, and if so returns the corresponding
-- Restriction_Parameter_Id value, otherwise returns
-- Not_A_Restriction_Parameter_Id.
end Restrict;
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