1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUN-TIME COMPONENTS                         --
4--                                                                          --
5--                      S Y S T E M . W I D _ E N U M                       --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2009, 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
32with Ada.Unchecked_Conversion;
33
34package body System.Wid_Enum is
35
36   -------------------------
37   -- Width_Enumeration_8 --
38   -------------------------
39
40   function Width_Enumeration_8
41     (Names   : String;
42      Indexes : System.Address;
43      Lo, Hi  : Natural)
44      return    Natural
45   is
46      pragma Warnings (Off, Names);
47
48      W : Natural;
49
50      type Natural_8 is range 0 .. 2 ** 7 - 1;
51      type Index_Table is array (Natural) of Natural_8;
52      type Index_Table_Ptr is access Index_Table;
53
54      function To_Index_Table_Ptr is
55        new Ada.Unchecked_Conversion (System.Address, Index_Table_Ptr);
56
57      IndexesT : constant Index_Table_Ptr := To_Index_Table_Ptr (Indexes);
58
59   begin
60      W := 0;
61
62      for J in Lo .. Hi loop
63         W := Natural'Max (W, Natural (IndexesT (J + 1) - IndexesT (J)));
64      end loop;
65
66      return W;
67   end Width_Enumeration_8;
68
69   --------------------------
70   -- Width_Enumeration_16 --
71   --------------------------
72
73   function Width_Enumeration_16
74     (Names   : String;
75      Indexes : System.Address;
76      Lo, Hi  : Natural)
77      return    Natural
78   is
79      pragma Warnings (Off, Names);
80
81      W : Natural;
82
83      type Natural_16 is range 0 .. 2 ** 15 - 1;
84      type Index_Table is array (Natural) of Natural_16;
85      type Index_Table_Ptr is access Index_Table;
86
87      function To_Index_Table_Ptr is
88        new Ada.Unchecked_Conversion (System.Address, Index_Table_Ptr);
89
90      IndexesT : constant Index_Table_Ptr := To_Index_Table_Ptr (Indexes);
91
92   begin
93      W := 0;
94
95      for J in Lo .. Hi loop
96         W := Natural'Max (W, Natural (IndexesT (J + 1) - IndexesT (J)));
97      end loop;
98
99      return W;
100   end Width_Enumeration_16;
101
102   --------------------------
103   -- Width_Enumeration_32 --
104   --------------------------
105
106   function Width_Enumeration_32
107     (Names   : String;
108      Indexes : System.Address;
109      Lo, Hi  : Natural)
110      return    Natural
111   is
112      pragma Warnings (Off, Names);
113
114      W : Natural;
115
116      type Natural_32 is range 0 .. 2 ** 31 - 1;
117      type Index_Table is array (Natural) of Natural_32;
118      type Index_Table_Ptr is access Index_Table;
119
120      function To_Index_Table_Ptr is
121        new Ada.Unchecked_Conversion (System.Address, Index_Table_Ptr);
122
123      IndexesT : constant Index_Table_Ptr := To_Index_Table_Ptr (Indexes);
124
125   begin
126      W := 0;
127
128      for J in Lo .. Hi loop
129         W := Natural'Max (W, Natural (IndexesT (J + 1) - IndexesT (J)));
130      end loop;
131
132      return W;
133   end Width_Enumeration_32;
134
135end System.Wid_Enum;
136