gcc/ada/prj-ext.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              P R J . E X T                               --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --             Copyright (C) 2000 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,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, 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 GNAT.HTable;
  28 with GNAT.OS_Lib; use GNAT.OS_Lib;
  29 with Namet;       use Namet;
  30 with Prj.Com;     use Prj.Com;
  31 with Stringt;     use Stringt;
  32 with Types;       use Types;
  33
  34 package body Prj.Ext is
  35
  36    package Htable is new GNAT.HTable.Simple_HTable
  37      (Header_Num => Header_Num,
  38       Element    => String_Id,
  39       No_Element => No_String,
  40       Key        => Name_Id,
  41       Hash       => Hash,
  42       Equal      => "=");
  43
  44    ---------
  45    -- Add --
  46    ---------
  47
  48    procedure Add
  49      (External_Name : String;
  50       Value         : String)
  51    is
  52       The_Key   : Name_Id;
  53       The_Value : String_Id;
  54
  55    begin
  56       Start_String;
  57       Store_String_Chars (Value);
  58       The_Value := End_String;
  59       Name_Len := External_Name'Length;
  60       Name_Buffer (1 .. Name_Len) := External_Name;
  61       The_Key := Name_Find;
  62       Htable.Set (The_Key, The_Value);
  63    end Add;
  64
  65    -----------
  66    -- Check --
  67    -----------
  68
  69    function Check (Declaration : String) return Boolean is
  70    begin
  71       for Equal_Pos in Declaration'Range loop
  72
  73          if Declaration (Equal_Pos) = '=' then
  74             exit when Equal_Pos = Declaration'First;
  75             exit when Equal_Pos = Declaration'Last;
  76             Add
  77               (External_Name =>
  78                  Declaration (Declaration'First .. Equal_Pos - 1),
  79                Value =>
  80                  Declaration (Equal_Pos + 1 .. Declaration'Last));
  81             return True;
  82          end if;
  83
  84       end loop;
  85
  86       return False;
  87    end Check;
  88
  89    --------------
  90    -- Value_Of --
  91    --------------
  92
  93    function Value_Of
  94      (External_Name : Name_Id;
  95       With_Default  : String_Id := No_String)
  96       return          String_Id
  97    is
  98       The_Value : String_Id;
  99
 100    begin
 101       The_Value := Htable.Get (External_Name);
 102
 103       if The_Value /= No_String then
 104          return The_Value;
 105       end if;
 106
 107       --  Find if it is an environment.
 108       --  If it is, put the value in the hash table.
 109
 110       declare
 111          Env_Value : constant String_Access :=
 112            Getenv (Get_Name_String (External_Name));
 113
 114       begin
 115          if Env_Value /= null and then Env_Value'Length > 0 then
 116             Start_String;
 117             Store_String_Chars (Env_Value.all);
 118             The_Value := End_String;
 119             Htable.Set (External_Name, The_Value);
 120             return The_Value;
 121
 122          else
 123             return With_Default;
 124          end if;
 125       end;
 126    end Value_Of;
 127
 128 end Prj.Ext;