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