getopt.c revision 126696 
1/*	$NetBSD: getopt.c,v 1.26 2003/08/07 16:43:40 agc Exp $	*/
2
3/*
4 * Copyright (c) 1987, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#if defined(LIBC_SCCS) && !defined(lint)
37static char sccsid[] = "@(#)getopt.c	8.3 (Berkeley) 4/27/95";
38#endif /* LIBC_SCCS and not lint */
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD: head/lib/libc/stdlib/getopt.c 126696 2004-03-06 17:05:45Z ache $");
41
42#include "namespace.h"
43#include <stdio.h>
44#include <stdlib.h>
45#include <string.h>
46#include <unistd.h>
47#include "un-namespace.h"
48
49#include "libc_private.h"
50
51int	opterr = 1,		/* if error message should be printed */
52	optind = 1,		/* index into parent argv vector */
53	optopt,			/* character checked for validity */
54	optreset;		/* reset getopt */
55char	*optarg;		/* argument associated with option */
56
57#define	BADCH	(int)'?'
58#define	BADARG	(int)':'
59#define	EMSG	""
60
61/*
62 * getopt --
63 *	Parse argc/argv argument vector.
64 */
65int
66getopt(nargc, nargv, ostr)
67	int nargc;
68	char * const nargv[];
69	const char *ostr;
70{
71	static char *place = EMSG;		/* option letter processing */
72	char *oli;				/* option letter list index */
73
74	if (optreset || *place == 0) {		/* update scanning pointer */
75		optreset = 0;
76		place = nargv[optind];
77		if (optind >= nargc || *place++ != '-') {
78			/* Argument is absent or is not an option */
79			place = EMSG;
80			return (-1);
81		}
82		optopt = *place++;
83		if (optopt == '-' && *place == 0) {
84			/* "--" => end of options */
85			++optind;
86			place = EMSG;
87			return (-1);
88		}
89		if (optopt == 0) {
90			/* Solitary '-', treat as a '-' option
91			   if the program (eg su) is looking for it. */
92			place = EMSG;
93			if (strchr(ostr, '-') == NULL)
94				return (-1);
95			optopt = '-';
96		}
97	} else
98		optopt = *place++;
99
100	/* See if option letter is one the caller wanted... */
101	if (optopt == ':' || (oli = strchr(ostr, optopt)) == NULL) {
102		if (*place == 0)
103			++optind;
104		if (opterr && *ostr != ':')
105			(void)fprintf(stderr,
106			    "%s: illegal option -- %c\n", _getprogname(),
107			    optopt);
108		return (BADCH);
109	}
110
111	/* Does this option need an argument? */
112	if (oli[1] != ':') {
113		/* don't need argument */
114		optarg = NULL;
115		if (*place == 0)
116			++optind;
117	} else {
118		/* Option-argument is either the rest of this argument or the
119		   entire next argument. */
120		if (*place)
121			optarg = place;
122		else if (nargc > ++optind)
123			optarg = nargv[optind];
124		else {
125			/* option-argument absent */
126			place = EMSG;
127			if (*ostr == ':')
128				return (BADARG);
129			if (opterr)
130				(void)fprintf(stderr,
131				    "%s: option requires an argument -- %c\n",
132				    _getprogname(), optopt);
133			return (BADCH);
134		}
135		place = EMSG;
136		++optind;
137	}
138	return (optopt);			/* return option letter */
139}
140