gcc/m2/gm2-libs/Args.mod

   1 (* Args.mod provide access to command line arguments.
   2
   3 Copyright (C) 2001-2024 Free Software Foundation, Inc.
   4 Contributed by Gaius Mulley <gaius@glam.ac.uk>.
   5
   6 This file is part of GNU Modula-2.
   7
   8 GNU Modula-2 is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GNU Modula-2 is distributed in the hope that it will be useful, but
  14 WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 General Public License for more details.
  17
  18 Under Section 7 of GPL version 3, you are granted additional
  19 permissions described in the GCC Runtime Library Exception, version
  20 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 IMPLEMENTATION MODULE Args ;
  28
  29
  30 FROM UnixArgs IMPORT GetArgC, GetArgV ;
  31 FROM ASCII IMPORT nul ;
  32
  33
  34 CONST
  35    MaxArgs   =  255 ;
  36    MaxString = 4096 ;
  37
  38
  39 (*
  40    Source allows us to examine the ArgV contents.
  41 *)
  42
  43 VAR
  44    Source: POINTER TO ARRAY [0..MaxArgs] OF
  45            POINTER TO ARRAY [0..MaxString] OF CHAR ;
  46
  47
  48 (*
  49    GetArg - returns the nth argument from the command line.
  50             The success of the operation is returned.
  51 *)
  52
  53 PROCEDURE GetArg (VAR a: ARRAY OF CHAR; n: CARDINAL) : BOOLEAN ;
  54 VAR
  55    i   : INTEGER ;
  56    High,
  57    j   : CARDINAL ;
  58 BEGIN
  59    i := VAL (INTEGER, n) ;
  60    j := 0 ;
  61    High := HIGH(a) ;
  62    IF i < GetArgC ()
  63    THEN
  64       Source := GetArgV () ;
  65       WHILE (j<High) AND (Source^[i]^[j]#nul) DO
  66          a[j] := Source^[i]^[j] ;
  67          INC(j)
  68       END
  69    END ;
  70    IF j<=High
  71    THEN
  72       a[j] := nul
  73    END ;
  74    RETURN i < GetArgC ()
  75 END GetArg ;
  76
  77
  78 (*
  79    Narg - returns the number of arguments available from
  80           command line.
  81 *)
  82
  83 PROCEDURE Narg () : CARDINAL ;
  84 BEGIN
  85    RETURN GetArgC ()
  86 END Narg ;
  87
  88
  89 END Args.