1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- S Y S T E M . V A L _ W C H A R --
9 -- Copyright (C) 1992-2006, Free Software Foundation, Inc. --
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, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
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. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 with Interfaces; use Interfaces;
35 with System.Val_Util; use System.Val_Util;
36 with System.WCh_Cnv; use System.WCh_Cnv;
37 with System.WCh_Con; use System.WCh_Con;
39 package body System.Val_WChar is
41 --------------------------
42 -- Value_Wide_Character --
43 --------------------------
45 function Value_Wide_Character
47 EM : System.WCh_Con.WC_Encoding_Method) return Wide_Character
49 WC : constant Wide_Wide_Character := Value_Wide_Wide_Character (Str, EM);
50 WV : constant Unsigned_32 := Wide_Wide_Character'Pos (WC);
53 raise Constraint_Error
54 with "out of range character for Value attribute";
56 return Wide_Character'Val (WV);
58 end Value_Wide_Character;
60 -------------------------------
61 -- Value_Wide_Wide_Character --
62 -------------------------------
64 function Value_Wide_Wide_Character
66 EM : System.WCh_Con.WC_Encoding_Method) return Wide_Wide_Character
70 S : String (Str'Range) := Str;
73 Normalize_String (S, F, L);
75 -- Character literal case
77 if S (F) = ''' and then S (L) = ''' then
79 -- Must be at least three characters
82 raise Constraint_Error;
84 -- If just three characters, simple character case
87 return Wide_Wide_Character'Val (Character'Pos (S (F + 1)));
89 -- Only other possibility for quoted string is wide char sequence
94 W : Wide_Wide_Character;
96 function In_Char return Character;
97 -- Function for instantiations of Char_Sequence_To_UTF_32
103 function In_Char return Character is
108 raise Constraint_Error;
115 new Char_Sequence_To_UTF_32 (In_Char);
122 if S (F + 1) = '[' then
123 W := Wide_Wide_Character'Val (UTF_32 ('[', WCEM_Brackets));
126 W := Wide_Wide_Character'Val (UTF_32 (S (F + 1), EM));
130 raise Constraint_Error;
137 -- Deal with Hex_hhhhhhhh cases for wide_[wide_]character cases
139 elsif Str'Length = 12
140 and then Str (Str'First .. Str'First + 3) = "Hex_"
143 W : Unsigned_32 := 0;
146 for J in Str'First + 4 .. Str'First + 11 loop
147 W := W * 16 + Character'Pos (Str (J));
149 if Str (J) in '0' .. '9' then
150 W := W - Character'Pos ('0');
151 elsif Str (J) in 'A' .. 'F' then
152 W := W - Character'Pos ('A') + 10;
153 elsif Str (J) in 'a' .. 'f' then
154 W := W - Character'Pos ('a') + 10;
156 raise Constraint_Error;
160 if W > 16#7FFF_FFFF# then
161 raise Constraint_Error;
163 return Wide_Wide_Character'Val (W);
167 -- Otherwise must be one of the special names for Character
171 Wide_Wide_Character'Val (Character'Pos (Character'Value (Str)));
175 when Constraint_Error =>
176 raise Constraint_Error with "invalid string for value attribute";
177 end Value_Wide_Wide_Character;
179 end System.Val_WChar;