gcc/ada/s-imgwiu.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                       S Y S T E M . I M G _ W I U                        --
   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- --
  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.                                              --
  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 System.Unsigned_Types; use System.Unsigned_Types;
  35
  36 package body System.Img_WIU is
  37
  38    -----------------------------
  39    -- Set_Image_Width_Integer --
  40    -----------------------------
  41
  42    procedure Set_Image_Width_Integer
  43      (V : Integer;
  44       W : Integer;
  45       S : out String;
  46       P : in out Natural)
  47    is
  48       Start : Natural;
  49
  50    begin
  51       --  Positive case can just use the unsigned circuit directly
  52
  53       if V >= 0 then
  54          Set_Image_Width_Unsigned (Unsigned (V), W, S, P);
  55
  56       --  Negative case has to set a minus sign. Note also that we have to be
  57       --  careful not to generate overflow with the largest negative number.
  58
  59       else
  60          P := P + 1;
  61          S (P) := ' ';
  62          Start := P;
  63
  64          declare
  65             pragma Suppress (Overflow_Check);
  66             pragma Suppress (Range_Check);
  67          begin
  68             Set_Image_Width_Unsigned (Unsigned (-V), W - 1, S, P);
  69          end;
  70
  71          --  Set minus sign in last leading blank location. Because of the
  72          --  code above, there must be at least one such location.
  73
  74          while S (Start + 1) = ' ' loop
  75             Start := Start + 1;
  76          end loop;
  77
  78          S (Start) := '-';
  79       end if;
  80
  81    end Set_Image_Width_Integer;
  82
  83    ------------------------------
  84    -- Set_Image_Width_Unsigned --
  85    ------------------------------
  86
  87    procedure Set_Image_Width_Unsigned
  88      (V : Unsigned;
  89       W : Integer;
  90       S : out String;
  91       P : in out Natural)
  92    is
  93       Start : constant Natural := P;
  94       F, T  : Natural;
  95
  96       procedure Set_Digits (T : Unsigned);
  97       --  Set digits of absolute value of T
  98
  99       procedure Set_Digits (T : Unsigned) is
 100       begin
 101          if T >= 10 then
 102             Set_Digits (T / 10);
 103             P := P + 1;
 104             S (P) := Character'Val (T mod 10 + Character'Pos ('0'));
 105          else
 106             P := P + 1;
 107             S (P) := Character'Val (T + Character'Pos ('0'));
 108          end if;
 109       end Set_Digits;
 110
 111    --  Start of processing for Set_Image_Width_Unsigned
 112
 113    begin
 114       Set_Digits (V);
 115
 116       --  Add leading spaces if required by width parameter
 117
 118       if P - Start < W then
 119          F := P;
 120          P := P + (W - (P - Start));
 121          T := P;
 122
 123          while F > Start loop
 124             S (T) := S (F);
 125             T := T - 1;
 126             F := F - 1;
 127          end loop;
 128
 129          for J in Start + 1 .. T loop
 130             S (J) := ' ';
 131          end loop;
 132       end if;
 133
 134    end Set_Image_Width_Unsigned;
 135
 136 end System.Img_WIU;