gcc/ada/switch.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                               S W I T C H                                --
   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 -- GNAT was originally developed  by the GNAT team at  New York University. --
  23 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  24 --                                                                          --
  25 ------------------------------------------------------------------------------
  26
  27 with Osint;
  28
  29 package body Switch is
  30
  31    ----------------
  32    -- Bad_Switch --
  33    ----------------
  34
  35    procedure Bad_Switch (Switch : Character) is
  36    begin
  37       Osint.Fail ("invalid switch: ", (1 => Switch));
  38    end Bad_Switch;
  39
  40    procedure Bad_Switch (Switch : String) is
  41    begin
  42       Osint.Fail ("invalid switch: ", Switch);
  43    end Bad_Switch;
  44
  45    -------------------------
  46    -- Is_Front_End_Switch --
  47    -------------------------
  48
  49    function Is_Front_End_Switch (Switch_Chars : String) return Boolean is
  50       Ptr : constant Positive := Switch_Chars'First;
  51    begin
  52       return Is_Switch (Switch_Chars)
  53         and then
  54           (Switch_Chars (Ptr + 1) = 'I'
  55             or else (Switch_Chars'Length >= 5
  56                       and then Switch_Chars (Ptr + 1 .. Ptr + 4) = "gnat")
  57             or else (Switch_Chars'Length >= 5
  58                       and then Switch_Chars (Ptr + 2 .. Ptr + 4) = "RTS"));
  59    end Is_Front_End_Switch;
  60
  61    ---------------
  62    -- Is_Switch --
  63    ---------------
  64
  65    function Is_Switch (Switch_Chars : String) return Boolean is
  66    begin
  67       return Switch_Chars'Length > 1
  68         and then Switch_Chars (Switch_Chars'First) = '-';
  69    end Is_Switch;
  70
  71    --------------
  72    -- Scan_Nat --
  73    --------------
  74
  75    procedure Scan_Nat
  76      (Switch_Chars : String;
  77       Max          : Integer;
  78       Ptr          : in out Integer;
  79       Result       : out Nat;
  80       Switch       : Character)
  81    is
  82    begin
  83       Result := 0;
  84
  85       if Ptr > Max or else Switch_Chars (Ptr) not in '0' .. '9' then
  86          Osint.Fail ("missing numeric value for switch: ", (1 => Switch));
  87
  88       else
  89          while Ptr <= Max and then Switch_Chars (Ptr) in '0' .. '9' loop
  90             Result := Result * 10 +
  91               Character'Pos (Switch_Chars (Ptr)) - Character'Pos ('0');
  92             Ptr := Ptr + 1;
  93
  94             if Result > Switch_Max_Value then
  95                Osint.Fail
  96                  ("numeric value out of range for switch: ", (1 => Switch));
  97             end if;
  98          end loop;
  99       end if;
 100    end Scan_Nat;
 101
 102    --------------
 103    -- Scan_Pos --
 104    --------------
 105
 106    procedure Scan_Pos
 107      (Switch_Chars : String;
 108       Max          : Integer;
 109       Ptr          : in out Integer;
 110       Result       : out Pos;
 111       Switch       : Character)
 112    is
 113       Temp : Nat;
 114
 115    begin
 116       Scan_Nat (Switch_Chars, Max, Ptr, Temp, Switch);
 117
 118       if Temp = 0 then
 119          Osint.Fail ("numeric value out of range for switch: ", (1 => Switch));
 120       end if;
 121
 122       Result := Temp;
 123    end Scan_Pos;
 124
 125 end Switch;