1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUNTIME COMPONENTS                          --
4--                                                                          --
5--                       S Y S T E M . P A C K _ 2 0                        --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-1999 Free Software Foundation, Inc.          --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 2,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
17-- for  more details.  You should have  received  a copy of the GNU General --
18-- Public License  distributed with GNAT;  see file COPYING.  If not, write --
19-- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
20-- MA 02111-1307, USA.                                                      --
21--                                                                          --
22-- As a special exception,  if other files  instantiate  generics from this --
23-- unit, or you link  this unit with other files  to produce an executable, --
24-- this  unit  does not  by itself cause  the resulting  executable  to  be --
25-- covered  by the  GNU  General  Public  License.  This exception does not --
26-- however invalidate  any other reasons why  the executable file  might be --
27-- covered by the  GNU Public License.                                      --
28--                                                                          --
29-- GNAT was originally developed  by the GNAT team at  New York University. --
30-- Extensive contributions were provided by Ada Core Technologies Inc.      --
31--                                                                          --
32------------------------------------------------------------------------------
33
34--  Handling of packed arrays with Component_Size = 20
35
36package System.Pack_20 is
37pragma Preelaborate (Pack_20);
38
39   Bits : constant := 20;
40
41   type Bits_20 is mod 2 ** Bits;
42   for Bits_20'Size use Bits;
43
44   function Get_20 (Arr : System.Address; N : Natural) return Bits_20;
45   --  Arr is the address of the packed array, N is the zero-based
46   --  subscript. This element is extracted and returned.
47
48   procedure Set_20 (Arr : System.Address; N : Natural; E : Bits_20);
49   --  Arr is the address of the packed array, N is the zero-based
50   --  subscript. This element is set to the given value.
51
52   function GetU_20 (Arr : System.Address; N : Natural) return Bits_20;
53   --  Arr is the address of the packed array, N is the zero-based
54   --  subscript. This element is extracted and returned. This version
55   --  is used when Arr may represent an unaligned address.
56
57   procedure SetU_20 (Arr : System.Address; N : Natural; E : Bits_20);
58   --  Arr is the address of the packed array, N is the zero-based
59   --  subscript. This element is set to the given value. This version
60   --  is used when Arr may represent an unaligned address
61
62end System.Pack_20;
63