xref: /f-stack/tools/compat/getopt.c (revision a9e7dcf4)
1 /*	$NetBSD: getopt.c,v 1.29 2014/06/05 22:00:22 christos 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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if defined(LIBC_SCCS) && !defined(lint)
33 static char sccsid[] = "@(#)getopt.c	8.3 (Berkeley) 4/27/95";
34 #endif /* LIBC_SCCS and not lint */
35 #include <sys/cdefs.h>
36 #ifndef FSTACK
37 __FBSDID("$FreeBSD$");
38 
39 #include "namespace.h"
40 #endif
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 #ifndef FSTACK
46 #include "un-namespace.h"
47 
48 #include "libc_private.h"
49 #endif
50 
51 int	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 */
55 char	*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  */
65 int
66 getopt(int nargc, char * const nargv[], const char *ostr)
67 {
68 	static char *place = EMSG;		/* option letter processing */
69 	char *oli;				/* option letter list index */
70 
71 	if (optreset || *place == 0) {		/* update scanning pointer */
72 		optreset = 0;
73 		place = nargv[optind];
74 		if (optind >= nargc || *place++ != '-') {
75 			/* Argument is absent or is not an option */
76 			place = EMSG;
77 			return (-1);
78 		}
79 		optopt = *place++;
80 		if (optopt == '-' && *place == 0) {
81 			/* "--" => end of options */
82 			++optind;
83 			place = EMSG;
84 			return (-1);
85 		}
86 		if (optopt == 0) {
87 			/* Solitary '-', treat as a '-' option
88 			   if the program (eg su) is looking for it. */
89 			place = EMSG;
90 			if (strchr(ostr, '-') == NULL)
91 				return (-1);
92 			optopt = '-';
93 		}
94 	} else
95 		optopt = *place++;
96 
97 	/* See if option letter is one the caller wanted... */
98 	if (optopt == ':' || (oli = strchr(ostr, optopt)) == NULL) {
99 		if (*place == 0)
100 			++optind;
101 		if (opterr && *ostr != ':')
102 			(void)fprintf(stderr,
103 #ifndef FSTACK
104 			    "%s: illegal option -- %c\n", _getprogname(),
105 #else
106 			    "illegal option -- %c\n",
107 #endif
108 			    optopt);
109 		return (BADCH);
110 	}
111 
112 	/* Does this option need an argument? */
113 	if (oli[1] != ':') {
114 		/* don't need argument */
115 		optarg = NULL;
116 		if (*place == 0)
117 			++optind;
118 	} else {
119 		/* Option-argument is either the rest of this argument or the
120 		   entire next argument. */
121 		if (*place)
122 			optarg = place;
123 		else if (oli[2] == ':')
124 			/*
125 			 * GNU Extension, for optional arguments if the rest of
126 			 * the argument is empty, we return NULL
127 			 */
128 			optarg = NULL;
129 		else if (nargc > ++optind)
130 			optarg = nargv[optind];
131 		else {
132 			/* option-argument absent */
133 			place = EMSG;
134 			if (*ostr == ':')
135 				return (BADARG);
136 			if (opterr)
137 				(void)fprintf(stderr,
138 #ifndef FSTACK
139 				    "%s: option requires an argument -- %c\n",
140 				    _getprogname(), optopt);
141 #else
142 					"option requires an argument -- %c\n", optopt);
143 #endif
144 			return (BADCH);
145 		}
146 		place = EMSG;
147 		++optind;
148 	}
149 	return (optopt);			/* return option letter */
150 }
151