gcc/ada/s-wwdwch.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                     S Y S T E M . W W D _ W C H A R                      --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2005, 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- --
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  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.                                              --
  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 with Interfaces; use Interfaces;
  35
  36 with System.WWd_Char;
  37
  38 package body System.Wwd_WChar is
  39
  40    ------------------------------------
  41    -- Wide_Wide_Width_Wide_Character --
  42    ------------------------------------
  43
  44    --  This is the case where we are talking about the Wide_Wide_Image of
  45    --  a Wide_Character, which is always the same character sequence as the
  46    --  Wide_Image of the same Wide_Character.
  47
  48    function Wide_Wide_Width_Wide_Character
  49      (Lo, Hi : Wide_Character) return Natural
  50    is
  51    begin
  52       return Wide_Width_Wide_Character (Lo, Hi);
  53    end Wide_Wide_Width_Wide_Character;
  54
  55    ------------------------------------
  56    -- Wide_Wide_Width_Wide_Wide_Char --
  57    ------------------------------------
  58
  59    function Wide_Wide_Width_Wide_Wide_Char
  60      (Lo, Hi : Wide_Wide_Character) return Natural
  61    is
  62       LV : constant Unsigned_32 := Wide_Wide_Character'Pos (Lo);
  63       HV : constant Unsigned_32 := Wide_Wide_Character'Pos (Hi);
  64
  65    begin
  66       --  Return zero if empty range
  67
  68       if LV > HV then
  69          return 0;
  70
  71       --  Return max value (12) for wide character (Hex_hhhhhhhh)
  72
  73       elsif HV > 255 then
  74          return 12;
  75
  76       --  If any characters in normal character range, then use normal
  77       --  Wide_Wide_Width attribute on this range to find out a starting point.
  78       --  Otherwise start with zero.
  79
  80       else
  81          return
  82            System.WWd_Char.Wide_Wide_Width_Character
  83              (Lo => Character'Val (LV),
  84               Hi => Character'Val (Unsigned_32'Min (255, HV)));
  85       end if;
  86    end Wide_Wide_Width_Wide_Wide_Char;
  87
  88    -------------------------------
  89    -- Wide_Width_Wide_Character --
  90    -------------------------------
  91
  92    function Wide_Width_Wide_Character
  93      (Lo, Hi : Wide_Character) return Natural
  94    is
  95       LV : constant Unsigned_32 := Wide_Character'Pos (Lo);
  96       HV : constant Unsigned_32 := Wide_Character'Pos (Hi);
  97
  98    begin
  99       --  Return zero if empty range
 100
 101       if LV > HV then
 102          return 0;
 103
 104       --  Return max value (12) for wide character (Hex_hhhhhhhh)
 105
 106       elsif HV > 255 then
 107          return 12;
 108
 109       --  If any characters in normal character range, then use normal
 110       --  Wide_Wide_Width attribute on this range to find out a starting point.
 111       --  Otherwise start with zero.
 112
 113       else
 114          return
 115            System.WWd_Char.Wide_Width_Character
 116              (Lo => Character'Val (LV),
 117               Hi => Character'Val (Unsigned_32'Min (255, HV)));
 118       end if;
 119    end Wide_Width_Wide_Character;
 120
 121    ------------------------------------
 122    -- Wide_Width_Wide_Wide_Character --
 123    ------------------------------------
 124
 125    function Wide_Width_Wide_Wide_Character
 126      (Lo, Hi : Wide_Wide_Character) return Natural
 127    is
 128    begin
 129       return Wide_Wide_Width_Wide_Wide_Char (Lo, Hi);
 130    end Wide_Width_Wide_Wide_Character;
 131
 132 end System.Wwd_WChar;