getopt.c

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/*
 * Copyright (c) 1987 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.
 *
 * Fri Jun 13 10:39:00 1997, tfelix@fred.net:
 *     Ported to Win32, changed index/rindex to strchr/strrchr
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getopt.c    4.13 (Berkeley) 2/23/91";
#endif /* LIBC_SCCS and not lint */

#include "precomp.h"

/*
 * get option letter from argument vector
 */
int opterr = 1,     /* if error message should be printed */
    optind = 1,     /* index into parent argv vector */
    optopt;         /* character checked for validity */
const char  *optarg;        /* argument associated with option */

#define BADCH   (int)'?'
#define EMSG    ""

int
getopt(int nargc, char * const *nargv, const char *ostr)
{
    static const char *place = EMSG;        /* option letter processing */
    register char *oli;         /* option letter list index */
    char *p;

    if (!*place) {              /* update scanning pointer */
        if (optind >= nargc || *(place = nargv[optind]) != '-') {
            place = EMSG;
            return(EOF);
        }
        if (place[1] && *++place == '-') {  /* found "--" */
            ++optind;
            place = EMSG;
            return(EOF);
        }
    }                   /* option letter okay? */
    if ((optopt = (int)*place++) == (int)':' ||
        !(oli = strchr(ostr, optopt))) {
        /*
         * if the user didn't specify '-' as an option,
         * assume it means EOF.
         */
        if (optopt == (int)'-')
            return(EOF);
        if (!*place)
            ++optind;
        if (opterr) {
            if (!(p = strrchr(*nargv, '/')))
                p = *nargv;
            else
                ++p;
            (void)fprintf(stderr, "%s: illegal option -- %c\n",
                p, 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 (!(p = strrchr(*nargv, '/')))
                p = *nargv;
            else
                ++p;
            if (opterr)
                (void)fprintf(stderr,
                    "%s: option requires an argument -- %c\n",
                    p, optopt);
            return(BADCH);
        }
        else                /* white space */
            optarg = nargv[optind];
        place = EMSG;
        ++optind;
    }
    return(optopt);             /* dump back option letter */
}