1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29#include <stdio.h>
30#include <string.h>
31#include "volume_error.h"
32#include "getopt_ext.h"
33
34/*
35 * Functions
36 */
37
38/*
39 * Identical to getopt(3), except that
40 *
41 * 1. If "-" is the first character of optstring, each non-option argv
42 *    element is handled as if it were the argument of an option with
43 *    character code GETOPT_NON_OPTION_ARG.  The result is that
44 *    GETOPT_DONE_PARSING will not be returned until the end of the
45 *    argument list has been reached.
46 *
47 *    This mirrors the functionality provided by GNU getopt.
48 *
49 * 2. GETOPT_ERR_INVALID_OPT or GETOPT_ERR_MISSING_ARG is returned
50 *    instead of '?'.  Subsequently "-?" can be used as a valid
51 *    option.
52 *
53 * 3. GETOPT_DONE_PARSING, GETOPT_ERR_INVALID_ARG, or
54 *    GETOPT_NON_OPTION_ARG is returned instead of -1.
55 *
56 * @param       argc
57 *              The number of arguments in the array
58 *
59 * @param       argv
60 *              The argument array
61 *
62 * @param       optstring
63 *              The option letters, with ':' following options with
64 *              required arguments.  See note about "-" as the first
65 *              character.
66 *
67 * @return      GETOPT_ERR_INVALID_OPT
68 *              if the option is not found in optstring
69 *
70 *              GETOPT_ERR_MISSING_ARG
71 *              if the option requires an argument which is missing
72 *
73 *              GETOPT_ERR_INVALID_ARG
74 *              if "-" is not the first character in optstring and a
75 *              non-option argument is encountered
76 *
77 *              GETOPT_NON_OPTION_ARG
78 *              if "-" is the first character in optstring and a
79 *              non-option argument is encountered
80 *
81 *              GETOPT_DONE_PARSING
82 *              if the end of the argument list is reached
83 *
84 *              <optopt>
85 *              the option character itself, if none of the above
86 *              scenarios applies.
87 */
88extern int
89getopt_ext(
90    int argc,
91    char * const argv[],
92    const char *optstring)
93{
94	int c;
95	int handle_non_options = (*optstring == '-');
96
97	/* Is "-" the first character of optstring? */
98	if (handle_non_options) {
99	    /* getopt(3) doesn't understand "-" */
100	    optstring++;
101	}
102
103	switch (c = getopt(argc, argv, optstring)) {
104
105		/*
106		 * getopt(3) returns -1 when 1) it encounters a non-option
107		 * argument or 2) reaches the end of the argument list.
108		 * Distinguish from the two possibilities.
109		 */
110	    case -1:
111		if (optind < argc) {
112		    optarg = argv[optind];
113
114		    /* Non-option argument found */
115		    if (handle_non_options) {
116			/* Non-option arguments are valid */
117			c = GETOPT_NON_OPTION_ARG;
118			optind++;
119		    } else {
120			/* Non-option arguments are invalid */
121			c = GETOPT_ERR_INVALID_ARG;
122		    }
123		} else {
124		    /* End of the argument list reached */
125		    c = GETOPT_DONE_PARSING;
126		}
127	    break;
128
129		/*
130		 * getopt(3) returns '?' when 1) the "-?" option is
131		 * encountered, 2) an invalid option is given or 3) a
132		 * valid option requiring an argument is found but no
133		 * argument is specified.  Distinguish from the three
134		 * possibilities.
135		 */
136	    case '?':
137		/* Is this an error or was -? encountered? */
138		if (optopt != '?') {
139		    if (strchr(optstring, optopt) == NULL) {
140			/* Invalid option */
141			c = GETOPT_ERR_INVALID_OPT;
142			optarg = argv[optind-1];
143		    } else {
144			/* Valid option without required argument */
145			c = GETOPT_ERR_MISSING_ARG;
146		    }
147		}
148	}
149
150	return (c);
151}
152