gcc/ada/s-vallli.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                       S Y S T E M . V A L _ L L I                        --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --   Copyright (C) 1992,1993,1994,1995,1996 Free Software Foundation, Inc.  --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- As a special exception,  if other files  instantiate  generics from this --
  24 -- unit, or you link  this unit with other files  to produce an executable, --
  25 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  26 -- covered  by the  GNU  General  Public  License.  This exception does not --
  27 -- however invalidate  any other reasons why  the executable file  might be --
  28 -- covered by the  GNU Public License.                                      --
  29 --                                                                          --
  30 -- GNAT was originally developed  by the GNAT team at  New York University. --
  31 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
  32 --                                                                          --
  33 ------------------------------------------------------------------------------
  34
  35 with System.Unsigned_Types; use System.Unsigned_Types;
  36 with System.Val_LLU;        use System.Val_LLU;
  37 with System.Val_Util;       use System.Val_Util;
  38
  39 package body System.Val_LLI is
  40
  41    ---------------------------
  42    -- Scn_Long_Long_Integer --
  43    ---------------------------
  44
  45    function Scan_Long_Long_Integer
  46      (Str  : String;
  47       Ptr  : access Integer;
  48       Max  : Integer)
  49       return Long_Long_Integer
  50    is
  51       Uval : Long_Long_Unsigned;
  52       --  Unsigned result
  53
  54       Minus : Boolean := False;
  55       --  Set to True if minus sign is present, otherwise to False
  56
  57       Start : Positive;
  58       --  Saves location of first non-blank (not used in this case)
  59
  60    begin
  61       Scan_Sign (Str, Ptr, Max, Minus, Start);
  62       Uval := Scan_Long_Long_Unsigned (Str, Ptr, Max);
  63
  64       --  Deal with overflow cases, and also with maximum negative number
  65
  66       if Uval > Long_Long_Unsigned (Long_Long_Integer'Last) then
  67          if Minus
  68            and then Uval = Long_Long_Unsigned (-(Long_Long_Integer'First)) then
  69             return Long_Long_Integer'First;
  70          else
  71             raise Constraint_Error;
  72          end if;
  73
  74       --  Negative values
  75
  76       elsif Minus then
  77          return -(Long_Long_Integer (Uval));
  78
  79       --  Positive values
  80
  81       else
  82          return Long_Long_Integer (Uval);
  83       end if;
  84
  85    end Scan_Long_Long_Integer;
  86
  87    -----------------------------
  88    -- Value_Long_Long_Integer --
  89    -----------------------------
  90
  91    function Value_Long_Long_Integer (Str : String) return Long_Long_Integer is
  92       V : Long_Long_Integer;
  93       P : aliased Integer := Str'First;
  94
  95    begin
  96       V := Scan_Long_Long_Integer (Str, P'Access, Str'Last);
  97       Scan_Trailing_Blanks (Str, P);
  98       return V;
  99
 100    end Value_Long_Long_Integer;
 101
 102 end System.Val_LLI;