getopt.c

/*
 * Copyright (c) 1987, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
 
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getopt.c    8.3 (Berkeley) 4/27/95";
#endif /* LIBC_SCCS and not lint */
 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "getopt.h"
 
OPENMESHDLLEXPORT int   opterr = 1,             /* if error message should be printed */
        optind = 1,             /* index into parent argv vector */
        optopt,                 /* character checked for validity */
        optreset;               /* reset getopt */
OPENMESHDLLEXPORT char  *optarg;                /* argument associated with option */
 
#define BADCH   (int)'?'
#define BADARG  (int)':'
#define EMSG    ""
 
/*
 * getopt --
 *      Parse argc/argv argument vector.
 */
OPENMESHDLLEXPORT int
getopt(int nargc, char * const *nargv, const char *ostr)
{
#  define __progname nargv[0]
        static char *place = EMSG;              /* option letter processing */
        char *oli;                              /* option letter list index */
 
        if (optreset || !*place) {              /* update scanning pointer */
                optreset = 0;
                if (optind >= nargc || *(place = nargv[optind]) != '-') {
                        place = EMSG;
                        return (-1);
                }
                if (place[1] && *++place == '-') {      /* found "--" */
                        ++optind;
                        place = EMSG;
                        return (-1);
                }
        }                                       /* option letter okay? */
        if ((optopt = (int)*place++) == (int)':' ||
            !(oli = (char *)strchr(ostr, optopt))) {
                /*
                 * if the user didn't specify '-' as an option,
                 * assume it means -1.
                 */
                if (optopt == (int)'-')
                        return (-1);
                if (!*place)
                        ++optind;
                if (opterr && *ostr != ':')
                        (void)fprintf(stderr,
                            "%s: illegal option -- %c\n", __progname, optopt);
                return (BADCH);
        }
        if (*++oli != ':') {                    /* don't need argument */
                optarg = NULL;
                if (!*place)
                        ++optind;
        }
        else {                                  /* need an argument */
                if (*place)                     /* no white space */
                        optarg = place;
                else if (nargc <= ++optind) {   /* no arg */
                        place = EMSG;
                        if (*ostr == ':')
                                return (BADARG);
                        if (opterr)
                                (void)fprintf(stderr,
                                    "%s: option requires an argument -- %c\n",
                                    __progname, optopt);
                        return (BADCH);
                }
                else                            /* white space */
                        optarg = nargv[optind];
                place = EMSG;
                ++optind;
        }
        return (optopt);                        /* dump back option letter */
}