1------------------------------------------------------------------------------
2--                                                                          --
3--                    GNAT RUN-TIME LIBRARY COMPONENTS                      --
4--                                                                          --
5--       S Y S T E M . C O M P A R E _ A R R A Y _ U N S I G N E D _ 8      --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 2002-2021, 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 3,  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.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNAT was originally developed  by the GNAT team at  New York University. --
28-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29--                                                                          --
30------------------------------------------------------------------------------
31
32--  This package contains functions for runtime comparisons on arrays whose
33--  elements are 8-bit discrete type values to be treated as unsigned.
34
35pragma Compiler_Unit_Warning;
36
37package System.Compare_Array_Unsigned_8 is
38
39   --  Note: although the functions in this package are in a sense Pure, the
40   --  package cannot be declared as Pure, since the arguments are addresses,
41   --  not the data, and the result is not pure wrt the address values.
42
43   function Compare_Array_U8
44     (Left      : System.Address;
45      Right     : System.Address;
46      Left_Len  : Natural;
47      Right_Len : Natural) return Integer;
48   --  Compare the array starting at address Left of length Left_Len with the
49   --  array starting at address Right of length Right_Len. The comparison is
50   --  in the normal Ada semantic sense of array comparison. The result is -1,
51   --  0, +1 for Left < Right, Left = Right, Left > Right respectively. This
52   --  function works with 4 byte words if the operands are aligned on 4-byte
53   --  boundaries and long enough.
54
55   function Compare_Array_U8_Unaligned
56     (Left      : System.Address;
57      Right     : System.Address;
58      Left_Len  : Natural;
59      Right_Len : Natural) return Integer;
60   --  Same functionality as Compare_Array_U8 but always proceeds by bytes.
61   --  Used when the caller knows that the operands are unaligned, or short
62   --  enough that it makes no sense to go by words.
63
64end System.Compare_Array_Unsigned_8;
65