gcc/m2/gm2-libs/GetOpt.mod

   1 (* GetOpt.mod allows users to manage long options to getopt.
   2
   3 Copyright (C) 2017-2024 Free Software Foundation, Inc.
   4 Contributed by Gaius Mulley <gaius.mulley@southwales.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 GetOpt ;  (*!m2pim+gm2*)
  28
  29 FROM DynamicStrings IMPORT string, InitStringCharStar ;
  30 FROM Storage IMPORT ALLOCATE, REALLOCATE, DEALLOCATE ;
  31 FROM MemUtils IMPORT MemCopy ;
  32
  33 IMPORT cgetopt ;
  34
  35
  36 TYPE
  37    LongOptions = POINTER TO RECORD
  38                                cptr: cgetopt.Options
  39                             END ;
  40
  41
  42 (*
  43    GetOpt - call C getopt and fill in the parameters:
  44             optarg, optind, opterr and optop.
  45 *)
  46
  47 PROCEDURE GetOpt (argc: INTEGER; argv: ADDRESS; optstring: String;
  48                   VAR optarg: String;
  49                   VAR optind, opterr, optopt: INTEGER) : CHAR ;
  50 VAR
  51    r: CHAR ;
  52 BEGIN
  53    r := cgetopt.getopt (argc, argv, string (optstring)) ;
  54    optarg := InitStringCharStar (cgetopt.optarg) ;
  55    opterr := cgetopt.opterr ;
  56    optopt := cgetopt.optopt ;
  57    RETURN r
  58 END GetOpt ;
  59
  60
  61 (*
  62    InitLongOptions - creates and returns a LongOptions empty array.
  63 *)
  64
  65 PROCEDURE InitLongOptions () : LongOptions ;
  66 VAR
  67    lo: LongOptions ;
  68 BEGIN
  69    NEW (lo) ;
  70    WITH lo^ DO
  71       cptr := cgetopt.InitOptions ()
  72    END ;
  73    RETURN lo
  74 END InitLongOptions ;
  75
  76
  77 (*
  78    AddLongOption - appends long option {name, has_arg, flag, val} to the
  79                    array of options and new long options array is returned.
  80                    The old array, lo, should no longer be used.
  81
  82    (from man 3 getopt)
  83        The meanings of the different fields are:
  84
  85        name   is the name of the long option.
  86
  87        has_arg
  88               is: no_argument (or 0) if the option does not take an  argument;  required_argument
  89               (or  1)  if  the  option  requires  an argument; or optional_argument (or 2) if the
  90               option takes an optional argument.
  91
  92        flag   specifies how results are returned for a  long  option.   If  flag  is  NULL,  then
  93               getopt_long()  returns  val.   (For example, the calling program may set val to the
  94               equivalent short option character.)  Otherwise, getopt_long() returns 0,  and  flag
  95               points to a variable which is set to val if the option is found, but left unchanged
  96               if the option is not found.
  97
  98        val    is the value to return, or to load into the variable pointed to by flag.
  99
 100        The last element of the array must be filled with zeros.
 101 *)
 102
 103 PROCEDURE AddLongOption (lo: LongOptions; index: CARDINAL;
 104                          name: String; has_arg: INTEGER;
 105                          VAR flag: INTEGER; val: INTEGER) : LongOptions ;
 106 BEGIN
 107    cgetopt.SetOption (lo^.cptr, index, name, has_arg, flag, val) ;
 108    RETURN lo
 109 END AddLongOption ;
 110
 111
 112 (*
 113    KillLongOptions - returns NIL and also frees up memory associated with, lo.
 114 *)
 115
 116 PROCEDURE KillLongOptions (lo: LongOptions) : LongOptions ;
 117 BEGIN
 118    lo^.cptr := cgetopt.KillOptions (lo^.cptr) ;
 119    DISPOSE (lo) ;
 120    RETURN NIL
 121 END KillLongOptions ;
 122
 123
 124 (*
 125    GetOptLong - works like GetOpt but will accept long options (using two dashes).
 126                 If the program only accepts long options then optstring should be
 127                 an empty string, not NIL.
 128 *)
 129
 130 PROCEDURE GetOptLong (argc: INTEGER; argv: ADDRESS; optstring: String;
 131                       longopts: LongOptions; VAR longindex: INTEGER) : INTEGER ;
 132 BEGIN
 133    RETURN cgetopt.getopt_long (argc, argv, string (optstring),
 134                                cgetopt.GetLongOptionArray (longopts^.cptr), longindex)
 135 END GetOptLong ;
 136
 137
 138 (*
 139    GetOptLongOnly - works like GetOptLong except that a single dash can be used
 140                     for a long option.
 141 *)
 142
 143 PROCEDURE GetOptLongOnly (argc: INTEGER; argv: ADDRESS; optstring: String;
 144                           longopts: LongOptions; VAR longindex: INTEGER) : INTEGER ;
 145 BEGIN
 146    RETURN cgetopt.getopt_long_only (argc, argv, string (optstring),
 147                                     cgetopt.GetLongOptionArray (longopts^.cptr), longindex)
 148 END GetOptLongOnly ;
 149
 150
 151 END GetOpt.