------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S Y S T E M . P A R A M E T E R S -- -- -- -- S p e c -- -- -- -- $Revision: 1.1.1.1 $ -- -- -- Copyright (C) 1992-2001 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 is the RT-GNU/Linux version. -- Blank line intentional so that it lines up exactly with default. -- This package defines some system dependent parameters for GNAT. These -- are values that are referenced by the runtime library and are therefore -- relevant to the target machine. -- The parameters whose value is defined in the spec are not generally -- expected to be changed. If they are changed, it will be necessary to -- recompile the run-time library. -- The parameters which are defined by functions can be changed by modifying -- the body of System.Parameters in file s-parame.adb. A change to this body -- requires only rebinding and relinking of the application. -- Note: do not introduce any pragma Inline statements into this unit, since -- otherwise the relinking and rebinding capability would be deactivated. package System.Parameters is pragma Pure (Parameters); --------------------------------------- -- Task And Stack Allocation Control -- --------------------------------------- type Task_Storage_Size is new Integer; -- Type used in tasking units for task storage size type Size_Type is new Task_Storage_Size; -- Type used to provide task storage size to runtime Unspecified_Size : constant Size_Type := Size_Type'First; -- Value used to indicate that no size type is set subtype Ratio is Size_Type range -1 .. 100; Dynamic : constant Size_Type := 10; -- The secondary stack ratio is a constant between 0 and 100 which -- determines the percentage of the allocated task stack that is -- used by the secondary stack (the rest being the primary stack). -- The special value of minus one indicates that the secondary -- stack is to be allocated from the heap instead. Sec_Stack_Ratio : constant Ratio := Dynamic; -- This constant defines the handling of the secondary stack Sec_Stack_Dynamic : constant Boolean := Sec_Stack_Ratio = Dynamic; -- Convenient Boolean for testing for dynamic secondary stack function Default_Stack_Size return Size_Type; -- Default task stack size used if none is specified function Minimum_Stack_Size return Size_Type; -- Minimum task stack size permitted function Adjust_Storage_Size (Size : Size_Type) return Size_Type; -- Given the storage size stored in the TCB, return the Storage_Size -- value required by the RM for the Storage_Size attribute. The -- required adjustment is as follows: -- -- when Size = Unspecified_Size, return Default_Stack_Size -- when Size < Minimum_Stack_Size, return Minimum_Stack_Size -- otherwise return given Size Stack_Grows_Down : constant Boolean := True; -- This constant indicates whether the stack grows up (False) or -- down (True) in memory as functions are called. It is used for -- proper implementation of the stack overflow check. ---------------------------------------------- -- Characteristics of types in Interfaces.C -- ---------------------------------------------- long_bits : constant := Long_Integer'Size; -- Number of bits in type long and unsigned_long. The normal convention -- is that this is the same as type Long_Integer, but this is not true -- of all targets. For example, in OpenVMS long /= Long_Integer. ---------------------------------------------- -- Behavior of Pragma Finalize_Storage_Only -- ---------------------------------------------- -- Garbage_Collected is a Boolean constant whose value indicates the -- effect of the pragma Finalize_Storage_Entry on a controlled type. -- Garbage_Collected = False -- The system releases all storage on program termination only, -- but not other garbage collection occurs, so finalization calls -- are ommitted only for outer level onjects can be omitted if -- pragma Finalize_Storage_Only is used. -- Garbage_Collected = True -- The system provides full garbage collection, so it is never -- necessary to release storage for controlled objects for which -- a pragma Finalize_Storage_Only is used. Garbage_Collected : constant Boolean := False; -- The storage mode for this system (release on program exit) end System.Parameters;