/*
* 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"

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

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

/*
* getopt --
*      Parse argc/argv argument vector.
*/
int
getopt(int nargc, char * const *nargv, const char *ostr)
{
       char *cp;
       static char *__progname;
       static char *place = EMSG;              /* option letter processing */
       char *oli;                              /* option letter list index */

       if (__progname == NULL) {
               if ((cp = strrchr(nargv[0], '/')) != NULL)
                       __progname = cp + 1;
               else
                       __progname = nargv[0];
       }
       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);
               }
       }
       optopt = (int)*place++;
       if (optopt == (int)':') {               /* option letter okay? */
               if (!*place)
                       ++optind;
               if (opterr && *ostr != ':')
                       (void)fprintf(stderr,
                           "%s: illegal option -- %c\n", __progname, optopt);
               return (BADCH);
       }
       oli = strchr(ostr, optopt);
       if (!oli) {
               /*
                * 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 */
}