examples/Stdlib/ConsoleApp/GETOPT.C

/*
Copyright (c) 1997-2010 Nokia Corporation and/or its subsidiary(-ies). All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this
  list of conditions and the following disclaimer.
* 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.
* Neither the name of Nokia Corporation 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.

Description:  
*/


#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getopt.c    8.2 (Berkeley) 4/2/94";
#endif /* LIBC_SCCS and not lint */

#include <stdio.h>
#include <stdlib.h>
#include <string.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)
{
//      extern char *__progname;
        static char *place = EMSG;              /* option letter processing */
        char *oli=NULL;                         /* option letter list index */

        if (optreset || !*place) {              /* update scanning pointer */
                optreset = 0;
                if (optind >= nargc || *(place = nargv[optind]) != '-') {
                        place = EMSG;
                        return (EOF);
                }
                if (place[1] && *++place == '-') {      /* found "--" */
                        ++optind;
                        place = EMSG;
                        return (EOF);
                }
        }                                       /* option letter okay? */

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

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