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-- --
-- --
-- S Y S T E M . S T R E A M _ A T T R I B U T E S --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2003 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. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
-- This package contains the implementations of the stream attributes for
-- elementary types. These are the subprograms that are directly accessed
-- by occurrences of the stream attributes where the type is elementary.
-- We only provide the subprograms for the standard base types. For user
-- defined types, the subprogram for the corresponding root type is called
-- with an appropriate conversion.
with System;
with System.Unsigned_Types;
with Ada.Streams;
package System.Stream_Attributes is
pragma Preelaborate (Stream_Attributes);
pragma Suppress (Accessibility_Check, Stream_Attributes);
-- No need to check accessibility on arguments of subprograms
package UST renames System.Unsigned_Types;
subtype RST is Ada.Streams.Root_Stream_Type'Class;
subtype SEC is Ada.Streams.Stream_Element_Count;
-- Enumeration types are usually transferred using the routine for the
-- corresponding integer. The exception is that special routines are
-- provided for Boolean and the character types, in case the protocol
-- in use provides specially for these types.
-- Access types use either a thin pointer (single address) or fat pointer
-- (double address) form. The following types are used to hold access
-- values using unchecked conversions.
type Thin_Pointer is record
P1 : System.Address;
end record;
type Fat_Pointer is record
P1 : System.Address;
P2 : System.Address;
end record;
-- Treatment of enumeration types --
-- In this interface, there are no specific routines for general input
-- or output of enumeration types. Generally, enumeration types whose
-- representation is unsigned (no negative representation values) are
-- treated as unsigned integers, and enumeration types that do have
-- negative representation values are treated as signed integers.
-- An exception is that there are specialized routines for Boolean,
-- Character, and Wide_Character types, but these specialized routines
-- are used only if the type in question has a standard representation.
-- For the case of a non-standard representation (one where the size of
-- the first subtype is specified, or where an enumeration representation
-- clause is given, these three types are treated like any other cases
-- of enumeration types, as described above.
-- for
-- Input Functions --
-- Functions for S'Input attribute. These functions are also used for
-- S'Read, with the obvious transformation, since the input operation
-- is the same for all elementary types (no bounds or discriminants
-- are involved).
function I_AD (Stream : access RST) return Fat_Pointer;
function I_AS (Stream : access RST) return Thin_Pointer;
function I_B (Stream : access RST) return Boolean;
function I_C (Stream : access RST) return Character;
function I_F (Stream : access RST) return Float;
function I_I (Stream : access RST) return Integer;
function I_LF (Stream : access RST) return Long_Float;
function I_LI (Stream : access RST) return Long_Integer;
function I_LLF (Stream : access RST) return Long_Long_Float;
function I_LLI (Stream : access RST) return Long_Long_Integer;
function I_LLU (Stream : access RST) return UST.Long_Long_Unsigned;
function I_LU (Stream : access RST) return UST.Long_Unsigned;
function I_SF (Stream : access RST) return Short_Float;
function I_SI (Stream : access RST) return Short_Integer;
function I_SSI (Stream : access RST) return Short_Short_Integer;
function I_SSU (Stream : access RST) return UST.Short_Short_Unsigned;
function I_SU (Stream : access RST) return UST.Short_Unsigned;
function I_U (Stream : access RST) return UST.Unsigned;
function I_WC (Stream : access RST) return Wide_Character;
-- Output Procedures --
-- Procedures for S'Write attribute. These procedures are also used
-- for 'Output, since for elementary types there is no difference
-- between 'Write and 'Output because there are no discriminants
-- or bounds to be written.
procedure W_AD (Stream : access RST; Item : in Fat_Pointer);
procedure W_AS (Stream : access RST; Item : in Thin_Pointer);
procedure W_B (Stream : access RST; Item : in Boolean);
procedure W_C (Stream : access RST; Item : in Character);
procedure W_F (Stream : access RST; Item : in Float);
procedure W_I (Stream : access RST; Item : in Integer);
procedure W_LF (Stream : access RST; Item : in Long_Float);
procedure W_LI (Stream : access RST; Item : in Long_Integer);
procedure W_LLF (Stream : access RST; Item : in Long_Long_Float);
procedure W_LLI (Stream : access RST; Item : in Long_Long_Integer);
procedure W_LLU (Stream : access RST; Item : in UST.Long_Long_Unsigned);
procedure W_LU (Stream : access RST; Item : in UST.Long_Unsigned);
procedure W_SF (Stream : access RST; Item : in Short_Float);
procedure W_SI (Stream : access RST; Item : in Short_Integer);
procedure W_SSI (Stream : access RST; Item : in Short_Short_Integer);
procedure W_SSU (Stream : access RST; Item : in UST.Short_Short_Unsigned);
procedure W_SU (Stream : access RST; Item : in UST.Short_Unsigned);
procedure W_U (Stream : access RST; Item : in UST.Unsigned);
procedure W_WC (Stream : access RST; Item : in Wide_Character);
-- Composite Input/Output --
-- The following Boolean constant is defined and set to True only if the
-- stream representation of a series of elementary items of the same
-- type (one of the types handled by the above procedures) has the same
-- representation as an array of such items in memory. This allows such
-- a series of items to be read or written as a block, instead of
-- element by element.
-- If the stream representation does not have this property for all the
-- above types, then this constant can be omitted or set to False,
-- and the front end will generate element-by-element operations.
-- This interface assumes that a Stream_Element has the same size as
-- a Storage_Unit. If that is not the case, then this flag should
-- also be omitted (or set to False).
Block_Stream_Ops_OK : constant Boolean := True;
-- Set to False if block stream operations not permitted
pragma Inline (I_AD);
pragma Inline (I_AS);
pragma Inline (I_B);
pragma Inline (I_C);
pragma Inline (I_F);
pragma Inline (I_I);
pragma Inline (I_LF);
pragma Inline (I_LI);
pragma Inline (I_LLF);
pragma Inline (I_LLI);
pragma Inline (I_LLU);
pragma Inline (I_LU);
pragma Inline (I_SF);
pragma Inline (I_SI);
pragma Inline (I_SSI);
pragma Inline (I_SSU);
pragma Inline (I_SU);
pragma Inline (I_U);
pragma Inline (I_WC);
pragma Inline (W_AD);
pragma Inline (W_AS);
pragma Inline (W_B);
pragma Inline (W_C);
pragma Inline (W_F);
pragma Inline (W_I);
pragma Inline (W_LF);
pragma Inline (W_LI);
pragma Inline (W_LLF);
pragma Inline (W_LLI);
pragma Inline (W_LLU);
pragma Inline (W_LU);
pragma Inline (W_SF);
pragma Inline (W_SI);
pragma Inline (W_SSI);
pragma Inline (W_SSU);
pragma Inline (W_SU);
pragma Inline (W_U);
pragma Inline (W_WC);
end System.Stream_Attributes;