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    -------------------------
  41    -- Is_Front_End_Switch --
  42    -------------------------
  43
  44    function Is_Front_End_Switch (Switch_Chars : String) return Boolean is
  45       Ptr : constant Positive := Switch_Chars'First;
  46    begin
  47       return Is_Switch (Switch_Chars)
  48         and then
  49           (Switch_Chars (Ptr + 1) = 'I'
  50             or else (Switch_Chars'Length >= 5
  51                       and then Switch_Chars (Ptr + 1 .. Ptr + 4) = "gnat")
  52             or else (Switch_Chars'Length >= 5
  53                       and then Switch_Chars (Ptr + 2 .. Ptr + 4) = "RTS"));
  54    end Is_Front_End_Switch;
  55
  56    ---------------
  57    -- Is_Switch --
  58    ---------------
  59
  60    function Is_Switch (Switch_Chars : String) return Boolean is
  61    begin
  62       return Switch_Chars'Length > 1
  63         and then Switch_Chars (Switch_Chars'First) = '-';
  64    end Is_Switch;
  65
  66    ------------------------
  67    --------------
  68    -- Scan_Nat --
  69    --------------
  70
  71    procedure Scan_Nat
  72      (Switch_Chars : String;
  73       Max          : Integer;
  74       Ptr          : in out Integer;
  75       Result       : out Nat;
  76       Switch       : Character)
  77    is
  78    begin
  79       Result := 0;
  80
  81       if Ptr > Max or else Switch_Chars (Ptr) not in '0' .. '9' then
  82          Osint.Fail ("missing numeric value for switch: ", (1 => Switch));
  83
  84       else
  85          while Ptr <= Max and then Switch_Chars (Ptr) in '0' .. '9' loop
  86             Result := Result * 10 +
  87               Character'Pos (Switch_Chars (Ptr)) - Character'Pos ('0');
  88             Ptr := Ptr + 1;
  89
  90             if Result > Switch_Max_Value then
  91                Osint.Fail
  92                  ("numeric value out of range for switch: ", (1 => Switch));
  93             end if;
  94          end loop;
  95       end if;
  96    end Scan_Nat;
  97
  98    --------------
  99    -- Scan_Pos --
 100    --------------
 101
 102    procedure Scan_Pos
 103      (Switch_Chars : String;
 104       Max          : Integer;
 105       Ptr          : in out Integer;
 106       Result       : out Pos;
 107       Switch       : Character)
 108    is
 109       Temp : Nat;
 110
 111    begin
 112       Scan_Nat (Switch_Chars, Max, Ptr, Temp, Switch);
 113
 114       if Temp = 0 then
 115          Osint.Fail ("numeric value out of range for switch: ", (1 => Switch));
 116       end if;
 117
 118       Result := Temp;
 119    end Scan_Pos;
 120
 121 end Switch;