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.
- */
- #if defined(LIBC_SCCS) && !defined(lint)
- static char sccsid[] = "@(#)getopt.c 4.13 (Berkeley) 2/23/91";
- #endif /* LIBC_SCCS and not lint */
- #include "port.h"
- #include <stdio.h>
- #include <string.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 */
- char *optarg; /* argument associated with option */
- #define BADCH (int)'?'
- #define EMSG ""
- int
- getopt(int nargc, char** nargv, char* ostr)
- {
- static 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 -- %cn",
- 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 -- %cn",
- p, optopt);
- return(BADCH);
- }
- else /* white space */
- optarg = nargv[optind];
- place = EMSG;
- ++optind;
- }
- return(optopt); /* dump back option letter */
- }