freebsd-dev/gnu/usr.bin/sort/long-options.c

/* Utility to accept --help and --version options as unobtrusively as possible.
   Copyright (C) 1993, 1994 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* Jim Meyering (meyering@comco.com) */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <getopt.h>
#include "long-options.h"

static struct option const long_options[] =
{
  {"help", no_argument, 0, 'h'},
  {"version", no_argument, 0, 'v'},
  {0, 0, 0, 0}
};

/* Process long options --help and --version, but only if argc == 2.
   Be careful not to gobble up `--'.  */

void
parse_long_options (argc, argv, command_name, version_string, usage)
     int argc;
     char **argv;
     const char *command_name;
     const char *version_string;
     void (*usage)();
{
  int c;
  int saved_opterr;
  int saved_optind;

  saved_opterr = opterr;
  saved_optind = optind;

  /* Don't print an error message for unrecognized options.  */
  opterr = 0;

  if (argc == 2
      && (c = getopt_long (argc, argv, "+", long_options, (int *) 0)) != EOF)
    {
      switch (c)
	{
	case 'h':
	  (*usage) (0);

	case 'v':
	  printf ("%s - %s\n", command_name, version_string);
	  exit (0);

	default:
	  /* Don't process any other long-named options.  */
	  break;
	}
    }

  /* Restore previous value.  */
  opterr = saved_opterr;

  /* Restore optind in case it has advanced past a leading `--'.  */
  optind = saved_optind;
}