File : s-widllu.adb


   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                       S Y S T E M . W I D _ L L U                        --
   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 System.Unsigned_Types; use System.Unsigned_Types;
  33 
  34 package body System.Wid_LLU is
  35 
  36    ------------------------------
  37    -- Width_Long_Long_Unsigned --
  38    ------------------------------
  39 
  40    function Width_Long_Long_Unsigned
  41      (Lo, Hi : Long_Long_Unsigned)
  42       return   Natural
  43    is
  44       W : Natural;
  45       T : Long_Long_Unsigned;
  46 
  47    begin
  48       if Lo > Hi then
  49          return 0;
  50 
  51       else
  52          --  Minimum value is 2, one for sign, one for digit
  53 
  54          W := 2;
  55 
  56          --  Get max of absolute values, but avoid bomb if we have the maximum
  57          --  negative number (note that First + 1 has same digits as First)
  58 
  59          T := Long_Long_Unsigned'Max (Lo, Hi);
  60 
  61          --  Increase value if more digits required
  62 
  63          while T >= 10 loop
  64             T := T / 10;
  65             W := W + 1;
  66          end loop;
  67 
  68          return W;
  69       end if;
  70 
  71    end Width_Long_Long_Unsigned;
  72 
  73 end System.Wid_LLU;