getopt.c

Go to the documentation of this file.

/* src/port/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. 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.
 */
 
#include "c.h"
 
#include "pg_getopt.h"
 
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getopt.c    8.3 (Berkeley) 4/27/95";
#endif                          /* LIBC_SCCS and not lint */
 
 
/*
 * On OpenBSD and some versions of Solaris, opterr and friends are defined in
 * core libc rather than in a separate getopt module.  Define these variables
 * only if configure found they aren't there by default; otherwise, this
 * module and its callers will just use libc's variables.  (We assume that
 * testing opterr is sufficient for all of these.)
 */
#ifndef HAVE_INT_OPTERR
 
int         opterr = 1,         /* if error message should be printed */
            optind = 1,         /* index into parent argv vector */
            optopt;             /* character checked for validity */
char       *optarg;             /* argument associated with option */
 
#endif
 
#define BADCH   (int)'?'
#define BADARG  (int)':'
#define EMSG    ""
 
/*
 * getopt
 *  Parse argc/argv argument vector.
 *
 * This implementation does not use optreset.  Instead, we guarantee that
 * it can be restarted on a new argv array after a previous call returned -1,
 * if the caller resets optind to 1 before the first call of the new series.
 * (Internally, this means we must be sure to reset "place" to EMSG before
 * returning -1.)
 */
int
getopt(int nargc, char *const *nargv, const char *ostr)
{
    static char *place = EMSG;  /* option letter processing */
    char       *oli;            /* option letter list index */
 
    if (!*place)
    {                           /* update scanning pointer */
        if (optind >= nargc || *(place = nargv[optind]) != '-')
        {
            place = EMSG;
            return -1;
        }
        if (place[1] && *++place == '-' && place[1] == '\0')
        {                       /* found "--" */
            ++optind;
            place = EMSG;
            return -1;
        }
    }                           /* option letter okay? */
    if ((optopt = (int) *place++) == (int) ':' ||
        !(oli = strchr(ostr, optopt)))
    {
        /*
         * if the user didn't specify '-' as an option, assume it means -1.
         */
        if (optopt == (int) '-')
        {
            place = EMSG;
            return -1;
        }
        if (!*place)
            ++optind;
        if (opterr && *ostr != ':')
            (void) fprintf(stderr,
                           "illegal option -- %c\n", 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,
                               "option requires an argument -- %c\n",
                               optopt);
            return BADCH;
        }
        else
            /* white space */
            optarg = nargv[optind];
        place = EMSG;
        ++optind;
    }
    return optopt;              /* dump back option letter */
}