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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S Y S T E M . S T A N D A R D _ L I B R A R Y --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2010, 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/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package is included in all programs. It contains declarations that
-- are required to be part of every Ada program. A special mechanism is
-- required to ensure that these are loaded, since it may be the case in
-- some programs that the only references to these required packages are
-- from C code or from code generated directly by Gigi, and in both cases
-- the binder is not aware of such references.
-- System.Standard_Library also includes data that must be present in every
-- program, in particular data for all the standard exceptions, and also some
-- subprograms that must be present in every program.
-- The binder unconditionally includes s-stalib.ali, which ensures that this
-- package and the packages it references are included in all Ada programs,
-- together with the included data.
pragma Compiler_Unit;
pragma Polling (Off);
-- We must turn polling off for this unit, because otherwise we get
-- elaboration circularities with Ada.Exceptions if polling is on.
with Ada.Unchecked_Conversion;
package System.Standard_Library is
pragma Warnings (Off);
pragma Preelaborate_05;
pragma Warnings (On);
type Big_String_Ptr is access all String (Positive);
for Big_String_Ptr'Storage_Size use 0;
-- A non-fat pointer type for null terminated strings
function To_Ptr is
new Ada.Unchecked_Conversion (System.Address, Big_String_Ptr);
---------------------------------------------
-- Type For Enumeration Image Index Tables --
---------------------------------------------
-- Note: these types are declared at the start of this unit, since
-- they must appear before any enumeration types declared in this
-- unit. Note that the spec of system is already elaborated at
-- this point (since we are a child of system), which means that
-- enumeration types in package System cannot use these types.
type Image_Index_Table_8 is
array (Integer range <>) of Short_Short_Integer;
type Image_Index_Table_16 is
array (Integer range <>) of Short_Integer;
type Image_Index_Table_32 is
array (Integer range <>) of Integer;
-- These types are used to generate the index vector used for enumeration
-- type image tables. See spec of Exp_Imgv in the main GNAT sources for a
-- full description of the data structures that are used here.
-------------------------------------
-- Exception Declarations and Data --
-------------------------------------
type Raise_Action is access procedure;
-- A pointer to a procedure used in the Raise_Hook field
type Exception_Data;
type Exception_Data_Ptr is access all Exception_Data;
-- An equivalent of Exception_Id that is public
type Exception_Code is mod 2 ** Integer'Size;
-- A scalar value bound to some exception data. Typically used for
-- imported or exported exceptions on VMS. Having a separate type for this
-- is useful to enforce consistency throughout the various run-time units
-- handling such codes, and having it unsigned is the most appropriate
-- choice for it's currently single use on VMS.
-- ??? The construction in Cstand has no way to access the proper type
-- node for Exception_Code, and currently uses Standard_Unsigned as a
-- fallback. The representations shall match, and the size clause below
-- is aimed at ensuring that.
for Exception_Code'Size use Integer'Size;
-- The following record defines the underlying representation of exceptions
-- WARNING! Any changes to this may need to be reflected in the following
-- locations in the compiler and runtime code:
-- 1. The Internal_Exception routine in s-exctab.adb
-- 2. The processing in gigi that tests Not_Handled_By_Others
-- 3. Expand_N_Exception_Declaration in Exp_Ch11
-- 4. The construction of the exception type in Cstand
type Exception_Data is record
Not_Handled_By_Others : Boolean;
-- Normally set False, indicating that the exception is handled in the
-- usual way by others (i.e. an others handler handles the exception).
-- Set True to indicate that this exception is not caught by others
-- handlers, but must be explicitly named in a handler. This latter
-- setting is currently used by the Abort_Signal.
Lang : Character;
-- A character indicating the language raising the exception.
-- Set to "A" for exceptions defined by an Ada program.
-- Set to "V" for imported VMS exceptions.
Name_Length : Natural;
-- Length of fully expanded name of exception
Full_Name : System.Address;
-- Fully expanded name of exception, null terminated
-- You can use To_Ptr to convert this to a string.
HTable_Ptr : Exception_Data_Ptr;
-- Hash table pointer used to link entries together in the hash table
-- built (by Register_Exception in s-exctab.adb) for converting between
-- identities and names.
Import_Code : Exception_Code;
-- Value for imported exceptions. Needed only for the handling of
-- Import/Export_Exception for the VMS case, but present in all
-- implementations (we might well extend this mechanism for other
-- systems in the future).
Raise_Hook : Raise_Action;
-- This field can be used to place a "hook" on an exception. If the
-- value is non-null, then it points to a procedure which is called
-- whenever the exception is raised. This call occurs immediately,
-- before any other actions taken by the raise (and in particular
-- before any unwinding of the stack occurs).
end record;
-- Definitions for standard predefined exceptions defined in Standard,
-- Why are the NULs necessary here, seems like they should not be
-- required, since Gigi is supposed to add a Nul to each name ???
Constraint_Error_Name : constant String := "CONSTRAINT_ERROR" & ASCII.NUL;
Program_Error_Name : constant String := "PROGRAM_ERROR" & ASCII.NUL;
Storage_Error_Name : constant String := "STORAGE_ERROR" & ASCII.NUL;
Tasking_Error_Name : constant String := "TASKING_ERROR" & ASCII.NUL;
Abort_Signal_Name : constant String := "_ABORT_SIGNAL" & ASCII.NUL;
Numeric_Error_Name : constant String := "NUMERIC_ERROR" & ASCII.NUL;
-- This is used only in the Ada 83 case, but it is not worth having a
-- separate version of s-stalib.ads for use in Ada 83 mode.
Constraint_Error_Def : aliased Exception_Data :=
(Not_Handled_By_Others => False,
Lang => 'A',
Name_Length => Constraint_Error_Name'Length,
Full_Name => Constraint_Error_Name'Address,
HTable_Ptr => null,
Import_Code => 0,
Raise_Hook => null);
Numeric_Error_Def : aliased Exception_Data :=
(Not_Handled_By_Others => False,
Lang => 'A',
Name_Length => Numeric_Error_Name'Length,
Full_Name => Numeric_Error_Name'Address,
HTable_Ptr => null,
Import_Code => 0,
Raise_Hook => null);
Program_Error_Def : aliased Exception_Data :=
(Not_Handled_By_Others => False,
Lang => 'A',
Name_Length => Program_Error_Name'Length,
Full_Name => Program_Error_Name'Address,
HTable_Ptr => null,
Import_Code => 0,
Raise_Hook => null);
Storage_Error_Def : aliased Exception_Data :=
(Not_Handled_By_Others => False,
Lang => 'A',
Name_Length => Storage_Error_Name'Length,
Full_Name => Storage_Error_Name'Address,
HTable_Ptr => null,
Import_Code => 0,
Raise_Hook => null);
Tasking_Error_Def : aliased Exception_Data :=
(Not_Handled_By_Others => False,
Lang => 'A',
Name_Length => Tasking_Error_Name'Length,
Full_Name => Tasking_Error_Name'Address,
HTable_Ptr => null,
Import_Code => 0,
Raise_Hook => null);
Abort_Signal_Def : aliased Exception_Data :=
(Not_Handled_By_Others => True,
Lang => 'A',
Name_Length => Abort_Signal_Name'Length,
Full_Name => Abort_Signal_Name'Address,
HTable_Ptr => null,
Import_Code => 0,
Raise_Hook => null);
pragma Export (C, Constraint_Error_Def, "constraint_error");
pragma Export (C, Numeric_Error_Def, "numeric_error");
pragma Export (C, Program_Error_Def, "program_error");
pragma Export (C, Storage_Error_Def, "storage_error");
pragma Export (C, Tasking_Error_Def, "tasking_error");
pragma Export (C, Abort_Signal_Def, "_abort_signal");
Local_Partition_ID : Natural := 0;
-- This variable contains the local Partition_ID that will be used when
-- building exception occurrences. In distributed mode, it will be
-- set by each partition to the correct value during the elaboration.
type Exception_Trace_Kind is
(RM_Convention,
-- No particular trace is requested, only unhandled exceptions
-- in the environment task (following the RM) will be printed.
-- This is the default behavior.
Every_Raise,
-- Denotes every possible raise event, either explicit or due to
-- a specific language rule, within the context of a task or not.
Unhandled_Raise
-- Denotes the raise events corresponding to exceptions for which
-- there is no user defined handler.
);
-- Provide a way to denote different kinds of automatic traces related
-- to exceptions that can be requested.
Exception_Trace : Exception_Trace_Kind := RM_Convention;
pragma Atomic (Exception_Trace);
-- By default, follow the RM convention
-----------------
-- Subprograms --
-----------------
procedure Abort_Undefer_Direct;
pragma Inline (Abort_Undefer_Direct);
-- A little procedure that just calls Abort_Undefer.all, for use in
-- clean up procedures, which only permit a simple subprogram name.
procedure Adafinal;
-- Performs the Ada Runtime finalization the first time it is invoked.
-- All subsequent calls are ignored.
end System.Standard_Library;
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