1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUN-TIME COMPONENTS                         --
4--                                                                          --
5--                     A D A . C O M M A N D _ L I N E                      --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2018, 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
32with System; use System;
33
34package body Ada.Command_Line is
35
36   function Arg_Count return Natural;
37   pragma Import (C, Arg_Count, "__gnat_arg_count");
38
39   procedure Fill_Arg (A : System.Address; Arg_Num : Integer);
40   pragma Import (C, Fill_Arg, "__gnat_fill_arg");
41
42   function Len_Arg (Arg_Num : Integer) return Integer;
43   pragma Import (C, Len_Arg, "__gnat_len_arg");
44
45   -----------------------
46   -- Local Subprograms --
47   -----------------------
48
49   function Initialized return Boolean;
50   --  Checks to ensure that gnat_argc and gnat_argv have been properly
51   --  initialized.  Returns false if not, or if argv / argc are
52   --  unsupported on the target (e.g. VxWorks).
53
54   --------------
55   -- Argument --
56   --------------
57
58   function Argument (Number : Positive) return String is
59   begin
60      if Number > Argument_Count then
61         raise Constraint_Error;
62      end if;
63
64      declare
65         Num : constant Positive :=
66                 (if Remove_Args = null then Number else Remove_Args (Number));
67         Arg : aliased String (1 .. Len_Arg (Num));
68      begin
69         Fill_Arg (Arg'Address, Num);
70         return Arg;
71      end;
72   end Argument;
73
74   --------------------
75   -- Argument_Count --
76   --------------------
77
78   function Argument_Count return Natural is
79   begin
80      if not Initialized then
81         --  RM A.15 (11)
82         return 0;
83      end if;
84
85      if Remove_Args = null then
86         return Arg_Count - 1;
87      else
88         return Remove_Count;
89      end if;
90   end Argument_Count;
91
92   -----------------
93   -- Initialized --
94   -----------------
95
96   function Initialized return Boolean is
97      gnat_argv : System.Address;
98      pragma Import (C, gnat_argv, "gnat_argv");
99
100   begin
101      return gnat_argv /= System.Null_Address;
102   end Initialized;
103
104   ------------------
105   -- Command_Name --
106   ------------------
107
108   function Command_Name return String is
109   begin
110      if not Initialized then
111         return "";
112      end if;
113
114      declare
115         Arg : aliased String (1 .. Len_Arg (0));
116
117      begin
118         Fill_Arg (Arg'Address, 0);
119         return Arg;
120      end;
121   end Command_Name;
122
123end Ada.Command_Line;
124