src/gnu_getopt.h

   1 /*
   2  * Portability wrapper to provide <getopt.h> declarations when the
   3  * system is missing them.
   4  *
   5  * Copyright © 2024 Nick Bowler
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  */
  20
  21 /*
  22  * If either HAVE_GETOPT_LONG or HAVE_GETOPT_LONG_ONLY are defined to 1,
  23  * then the system <getopt.h> is used to get a declaration of struct
  24  * option and the global getopt variables.  If neither are defined,
  25  * then <getopt.h> is not included and replacements are provided.
  26  *
  27  * These replacements will interfere with POSIX getopt which uses the
  28  * same variable names so that cannot be used at the same time.  For
  29  * the same reason, do not use both getopt_long and getopt_long_only
  30  * in the same program, as some systems provide one but not both.
  31  */
  32
  33 #ifndef DX_GETOPT_H_
  34 #define DX_GETOPT_H_
  35
  36 #if HAVE_GETOPT_LONG || HAVE_GETOPT_LONG_ONLY
  37 #       include <getopt.h>
  38 #else
  39 struct option {
  40         const char *name;
  41         int has_arg, *flag, val;
  42 };
  43
  44 extern int optind, optopt, opterr;
  45 extern char *optarg;
  46 #endif
  47
  48 /* Local fallback implementation */
  49 int gnu_getopt(int, char **, const char *, const struct option *, int *, int);
  50
  51 #if !HAVE_GETOPT_LONG
  52 #define getopt_long(argc, argv, sopts, lopts, idx) \
  53         gnu_getopt(argc, argv, sopts, lopts, idx, 0)
  54 #endif
  55
  56 #if !HAVE_GETOPT_LONG_ONLY
  57 #define getopt_long_only(argc, argv, sopts, lopts, idx) \
  58         gnu_getopt(argc, argv, sopts, lopts, idx, 1)
  59 #endif
  60
  61 #endif