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-- --
-- --
-- A D A . S T R I N G S . U N B O U N D E D . A U X --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2021, 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 --
-- --
-- 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 --
-- <>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
-- This child package of Ada.Strings.Unbounded provides some specialized
-- access functions which are intended to allow more efficient use of the
-- facilities of Ada.Strings.Unbounded, particularly by other layered
-- utilities (such as GNAT.SPITBOL.Patterns).
package Ada.Strings.Unbounded.Aux is
pragma Preelaborate;
subtype Big_String is String (1 .. Positive'Last);
pragma Suppress_Initialization (Big_String);
-- Type used to obtain string access to given address. Initialization is
-- suppressed, since we never want to have variables of this type, and
-- we never want to attempt initialiazation of virtual variables of this
-- type (e.g. when pragma Normalize_Scalars is used).
type Big_String_Access is access all Big_String;
for Big_String_Access'Storage_Size use 0;
-- We use this access type to pass a pointer to an area of storage to be
-- accessed as a string. Of course when this pointer is used, it is the
-- responsibility of the accessor to ensure proper bounds. The storage
-- size clause ensures we do not allocate variables of this type.
procedure Get_String
(U : Unbounded_String;
S : out Big_String_Access;
L : out Natural);
pragma Inline (Get_String);
-- Return the internal string pointer used in the representation of an
-- unbounded string as well as the actual current length (which may be less
-- than S.all'Length because in general there can be extra space assigned).
-- The characters of this string may be not be modified via the returned
-- pointer, and are valid only as long as the original unbounded string is
-- not accessed or modified.
-- This procedure is much more efficient than the use of To_String
-- since it avoids the need to copy the string. The lower bound of the
-- referenced string returned by this call is always one, so the actual
-- string data is always accessible as S (1 .. L).
procedure Set_String
(U : out Unbounded_String;
Length : Positive;
Set : not null access procedure (S : out String));
pragma Inline (Set_String);
-- Create an unbounded string U with the given Length, using Set to fill
-- the contents of U.
end Ada.Strings.Unbounded.Aux;