File : s-widenu.adb
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 -- --
19 -- --
20 -- --
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 with Ada.Unchecked_Conversion;
33
34 package 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
135 end System.Wid_Enum;