xref: /titanic_51/usr/src/boot/lib/libstand/getopt.c (revision 4a5d661a82b942b6538acd26209d959ce98b593a)
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 <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #if defined(LIBC_SCCS) && !defined(lint)
34 static char sccsid[] = "@(#)getopt.c	8.3 (Berkeley) 4/27/95";
35 #endif /* LIBC_SCCS and not lint */
36 
37 #include "stand.h"
38 #include <string.h>
39 
40 int	opterr = 1,		/* if error message should be printed */
41 	optind = 1,		/* index into parent argv vector */
42 	optopt,			/* character checked for validity */
43 	optreset;		/* reset getopt */
44 char	*optarg;		/* argument associated with option */
45 
46 #define	BADCH	(int)'?'
47 #define	BADARG	(int)':'
48 #define	EMSG	""
49 
50 /*
51  * getopt --
52  *	Parse argc/argv argument vector.
53  */
54 int
55 getopt(int nargc, char * const *nargv, const char *ostr)
56 {
57 	static char *place = EMSG;		/* option letter processing */
58 	char *oli;				/* option letter list index */
59 
60 	if (optreset || !*place) {		/* update scanning pointer */
61 		optreset = 0;
62 		if (optind >= nargc || *(place = nargv[optind]) != '-') {
63 			place = EMSG;
64 			return (-1);
65 		}
66 		if (place[1] && *++place == '-') {	/* found "--" */
67 			++optind;
68 			place = EMSG;
69 			return (-1);
70 		}
71 	}					/* option letter okay? */
72 	if ((optopt = (int)*place++) == (int)':' ||
73 	    !(oli = strchr(ostr, optopt))) {
74 		/*
75 		 * if the user didn't specify '-' as an option,
76 		 * assume it means -1.
77 		 */
78 		if (optopt == (int)'-')
79 			return (-1);
80 		if (!*place)
81 			++optind;
82 		if (opterr && *ostr != ':')
83 			(void)printf("illegal option -- %c\n", optopt);
84 		return (BADCH);
85 	}
86 	if (*++oli != ':') {			/* don't need argument */
87 		optarg = NULL;
88 		if (!*place)
89 			++optind;
90 	}
91 	else {					/* need an argument */
92 		if (*place)			/* no white space */
93 			optarg = place;
94 		else if (nargc <= ++optind) {	/* no arg */
95 			place = EMSG;
96 			if (*ostr == ':')
97 				return (BADARG);
98 			if (opterr)
99 				(void)printf("option requires an argument -- %c\n", optopt);
100 			return (BADCH);
101 		}
102 	 	else				/* white space */
103 			optarg = nargv[optind];
104 		place = EMSG;
105 		++optind;
106 	}
107 	return (optopt);			/* dump back option letter */
108 }
109