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 2004 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26 /*
27 * Portions Copyright (c) 2005 Gunnar Ritter, Freiburg i. Br., Germany
28 *
29 * Sccsid @(#)getopt.c 1.7 (gritter) 6/22/05
30 */
31 /* from OpenSolaris "getopt.c 1.23 05/06/08 SMI" */
32
33 /* Copyright (c) 1988 AT&T */
34 /* All Rights Reserved */
35
36
37 /*
38 * See getopt(3C) and SUS/XPG getopt() for function definition and
39 * requirements.
40 *
41 * This actual implementation is a bit looser than the specification
42 * as it allows any character other than ':' to be used as an option
43 * character - The specification only guarantees the alnum characters
44 * ([a-z][A-Z][0-9]).
45 */
46
47 #include <unistd.h>
48 #include <string.h>
49 #include <stdio.h>
50
51 /*
52 * Generalized error processing macro. The parameter i is a pointer to
53 * the failed option string. If it is NULL, the character in c is converted
54 * to a string and displayed instead. s is the error text.
55 *
56 * This could be / should be a static function if it is used more, but
57 * that would require moving the 'optstring[0]' test outside of the
58 * function.
59 */
60 #define ERR(s, c) if (opterr && optstring[0] != ':') { \
61 char errbuf[256]; \
62 snprintf(errbuf, sizeof (errbuf), s, argv[0], c); \
63 write(2, errbuf, strlen(errbuf)); }
64
65 /*
66 * getopt_sp is required to keep state between successive calls to getopt()
67 * while extracting aggregated options (ie: -abcd). Hence, getopt() is not
68 * thread safe or reentrant, but it really doesn't matter.
69 *
70 * So, why isn't this "static" you ask? Because the historical Bourne
71 * shell has actually latched on to this little piece of private data.
72 */
73 int getopt_sp = 1;
74
75 /*
76 * Determine if the specified character (c) is present in the string
77 * (optstring) as a regular, single character option. If the option is found,
78 * return a pointer into optstring pointing at the option character,
79 * otherwise return null. The character ':' is not allowed.
80 */
81 static char *
parse(const char * optstring,const char c)82 parse(const char *optstring, const char c)
83 {
84 char *cp = (char *)optstring;
85
86 if (c == ':')
87 return (NULL);
88 do {
89 if (*cp == c)
90 return (cp);
91 } while (*cp++ != '\0');
92 return (NULL);
93 }
94
95 /*
96 * External function entry point.
97 */
98 int
getopt(int argc,char * const * argv,const char * optstring)99 getopt(int argc, char *const *argv, const char *optstring)
100 {
101 char c;
102 char *cp;
103
104 /*
105 * Has the end of the options been encountered? The following
106 * implements the SUS requirements:
107 *
108 * If, when getopt() is called:
109 * argv[optind] is a null pointer
110 * *argv[optind] is not the character '-'
111 * argv[optind] points to the string "-"
112 * getopt() returns -1 without changing optind. If
113 * argv[optind] points to the string "--"
114 * getopt() returns -1 after incrementing optind.
115 */
116 if (getopt_sp == 1) {
117 if (optind >= argc || argv[optind][0] != '-' ||
118 argv[optind] == NULL || argv[optind][1] == '\0')
119 return (EOF);
120 else if (strcmp(argv[optind], "--") == 0) {
121 optind++;
122 return (EOF);
123 }
124 }
125
126 /*
127 * Getting this far indicates that an option has been encountered.
128 * Note that the syntax of optstring applies special meanings to
129 * the characters ':' and '(', so they are not permissible as
130 * option letters. A special meaning is also applied to the ')'
131 * character, but its meaning can be determined from context.
132 * Note that the specification only requires that the alnum
133 * characters be accepted.
134 */
135 optopt = c = (unsigned char)argv[optind][getopt_sp];
136 optarg = NULL;
137 if ((cp = parse(optstring, c)) == NULL) {
138 /* LINTED: variable format specifier */
139 ERR("%s: illegal option -- %c\n", c);
140 if (argv[optind][++getopt_sp] == '\0') {
141 optind++;
142 getopt_sp = 1;
143 }
144 return ('?');
145 }
146 optopt = c = *cp;
147
148 /*
149 * A valid option has been identified. If it should have an
150 * option-argument, process that now. SUS defines the setting
151 * of optarg as follows:
152 *
153 * 1. If the option was the last character in the string pointed to
154 * by an element of argv, then optarg contains the next element
155 * of argv, and optind is incremented by 2. If the resulting
156 * value of optind is not less than argc, this indicates a
157 * missing option-argument, and getopt() returns an error
158 * indication.
159 *
160 * 2. Otherwise, optarg points to the string following the option
161 * character in that element of argv, and optind is incremented
162 * by 1.
163 *
164 * The second clause allows -abcd (where b requires an option-argument)
165 * to be interpreted as "-a -b cd".
166 */
167 if (*(cp + 1) == ':') {
168 /* The option takes an argument */
169 if (argv[optind][getopt_sp+1] != '\0') {
170 optarg = &argv[optind++][getopt_sp+1];
171 } else if (++optind >= argc) {
172 /* LINTED: variable format specifier */
173 ERR("%s: option requires an argument -- %c\n", c);
174 getopt_sp = 1;
175 optarg = NULL;
176 return (optstring[0] == ':' ? ':' : '?');
177 } else
178 optarg = argv[optind++];
179 getopt_sp = 1;
180 } else {
181 /* The option does NOT take an argument */
182 if (argv[optind][++getopt_sp] == '\0') {
183 getopt_sp = 1;
184 optind++;
185 }
186 optarg = NULL;
187 }
188 return (c);
189 } /* getopt() */
190