gcc/ada/libgnat/a-colien.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --         A D A . C O M M A N D _ L I N E . E N V I R O N M E N T          --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1996-2018, 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 -- As a special exception under Section 7 of GPL version 3, you are granted --
  19 -- additional permissions described in the GCC Runtime Library Exception,   --
  20 -- version 3.1, as published by the Free Software Foundation.               --
  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;
  33
  34 package body Ada.Command_Line.Environment is
  35
  36    -----------------------
  37    -- Environment_Count --
  38    -----------------------
  39
  40    function Environment_Count return Natural is
  41       function Env_Count return Natural;
  42       pragma Import (C, Env_Count, "__gnat_env_count");
  43
  44    begin
  45       return Env_Count;
  46    end Environment_Count;
  47
  48    -----------------------
  49    -- Environment_Value --
  50    -----------------------
  51
  52    function Environment_Value (Number : Positive) return String is
  53       procedure Fill_Env (E : System.Address; Env_Num : Integer);
  54       pragma Import (C, Fill_Env, "__gnat_fill_env");
  55
  56       function Len_Env (Env_Num : Integer) return Integer;
  57       pragma Import (C, Len_Env, "__gnat_len_env");
  58
  59    begin
  60       if Number > Environment_Count then
  61          raise Constraint_Error;
  62       end if;
  63
  64       declare
  65          Env : aliased String (1 .. Len_Env (Number - 1));
  66       begin
  67          Fill_Env (Env'Address, Number - 1);
  68          return Env;
  69       end;
  70    end Environment_Value;
  71
  72 end Ada.Command_Line.Environment;