xref: /freebsd/contrib/libarchive/unzip/cmdline.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
1 /*-
2  * Copyright (c) 2003-2008 Tim Kientzle
3  * 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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 /*
27  * Command line parser for bsdunzip.
28  */
29 
30 #include "bsdunzip_platform.h"
31 #ifdef HAVE_ERRNO_H
32 #include <errno.h>
33 #endif
34 #ifdef HAVE_STDLIB_H
35 #include <stdlib.h>
36 #endif
37 #ifdef HAVE_STRING_H
38 #include <string.h>
39 #endif
40 
41 #include "bsdunzip.h"
42 #include "err.h"
43 
44 /*
45  * Short options for bsdunzip.  Please keep this sorted.
46  */
47 static const char *short_options
48 	= "aCcd:fI:jLlnO:opP:qtuvx:yZ:";
49 
50 /*
51  * Long options for bsdunzip.  Please keep this list sorted.
52  *
53  * The symbolic names for options that lack a short equivalent are
54  * defined in bsdunzip.h.  Also note that so far I've found no need
55  * to support optional arguments to long options.  That would be
56  * a small change to the code below.
57  */
58 
59 static const struct bsdunzip_option {
60 	const char *name;
61 	int required;      /* 1 if this option requires an argument. */
62 	int equivalent;    /* Equivalent short option. */
63 } bsdunzip_longopts[] = {
64 	{ "version", 0, OPTION_VERSION },
65 	{ NULL, 0, 0 }
66 };
67 
68 /*
69  * This getopt implementation has two key features that common
70  * getopt_long() implementations lack.  Apart from those, it's a
71  * straightforward option parser, considerably simplified by not
72  * needing to support the wealth of exotic getopt_long() features.  It
73  * has, of course, been shamelessly tailored for bsdunzip.  (If you're
74  * looking for a generic getopt_long() implementation for your
75  * project, I recommend Gregory Pietsch's public domain getopt_long()
76  * implementation.)  The two additional features are:
77  */
78 
79 int
80 bsdunzip_getopt(struct bsdunzip *bsdunzip)
81 {
82 	enum { state_start = 0, state_next_word, state_short, state_long };
83 
84 	const struct bsdunzip_option *popt, *match, *match2;
85 	const char *p, *long_prefix;
86 	size_t optlength;
87 	int opt;
88 	int required;
89 
90 again:
91 	match = NULL;
92 	match2 = NULL;
93 	long_prefix = "--";
94 	opt = OPTION_NONE;
95 	required = 0;
96 	bsdunzip->argument = NULL;
97 
98 	/* First time through, initialize everything. */
99 	if (bsdunzip->getopt_state == state_start) {
100 		/* Skip program name. */
101 		++bsdunzip->argv;
102 		--bsdunzip->argc;
103 		if (*bsdunzip->argv == NULL)
104 			return (-1);
105 		bsdunzip->getopt_state = state_next_word;
106 	}
107 
108 	/*
109 	 * We're ready to look at the next word in argv.
110 	 */
111 	if (bsdunzip->getopt_state == state_next_word) {
112 		/* No more arguments, so no more options. */
113 		if (bsdunzip->argv[0] == NULL)
114 			return (-1);
115 		/* Doesn't start with '-', so no more options. */
116 		if (bsdunzip->argv[0][0] != '-')
117 			return (-1);
118 		/* "--" marks end of options; consume it and return. */
119 		if (strcmp(bsdunzip->argv[0], "--") == 0) {
120 			++bsdunzip->argv;
121 			--bsdunzip->argc;
122 			bsdunzip_optind++;
123 			return (-1);
124 		}
125 		/* Get next word for parsing. */
126 		bsdunzip->getopt_word = *bsdunzip->argv++;
127 		--bsdunzip->argc;
128 		bsdunzip_optind++;
129 		if (bsdunzip->getopt_word[1] == '-') {
130 			/* Set up long option parser. */
131 			bsdunzip->getopt_state = state_long;
132 			bsdunzip->getopt_word += 2; /* Skip leading '--' */
133 		} else {
134 			/* Set up short option parser. */
135 			bsdunzip->getopt_state = state_short;
136 			++bsdunzip->getopt_word;  /* Skip leading '-' */
137 		}
138 	}
139 
140 	/*
141 	 * We're parsing a group of POSIX-style single-character options.
142 	 */
143 	if (bsdunzip->getopt_state == state_short) {
144 		/* Peel next option off of a group of short options. */
145 		opt = *bsdunzip->getopt_word++;
146 		if (opt == '\0') {
147 			/* End of this group; recurse to get next option. */
148 			bsdunzip->getopt_state = state_next_word;
149 			goto again;
150 		}
151 
152 		/* Does this option take an argument? */
153 		p = strchr(short_options, opt);
154 		if (p == NULL)
155 			return ('?');
156 		if (p[1] == ':')
157 			required = 1;
158 
159 		/* If it takes an argument, parse that. */
160 		if (required) {
161 			/* If arg is run-in, bsdunzip->getopt_word already points to it. */
162 			if (bsdunzip->getopt_word[0] == '\0') {
163 				/* Otherwise, pick up the next word. */
164 				bsdunzip->getopt_word = *bsdunzip->argv;
165 				if (bsdunzip->getopt_word == NULL) {
166 					lafe_warnc(0,
167 					    "Option -%c requires an argument",
168 					    opt);
169 					return ('?');
170 				}
171 				++bsdunzip->argv;
172 				--bsdunzip->argc;
173 				bsdunzip_optind++;
174 			}
175 			bsdunzip->getopt_state = state_next_word;
176 			bsdunzip->argument = bsdunzip->getopt_word;
177 		}
178 	}
179 
180 	/* We're reading a long option */
181 	if (bsdunzip->getopt_state == state_long) {
182 		/* After this long option, we'll be starting a new word. */
183 		bsdunzip->getopt_state = state_next_word;
184 
185 		/* Option name ends at '=' if there is one. */
186 		p = strchr(bsdunzip->getopt_word, '=');
187 		if (p != NULL) {
188 			optlength = (size_t)(p - bsdunzip->getopt_word);
189 			bsdunzip->argument = (char *)(uintptr_t)(p + 1);
190 		} else {
191 			optlength = strlen(bsdunzip->getopt_word);
192 		}
193 
194 		/* Search the table for an unambiguous match. */
195 		for (popt = bsdunzip_longopts; popt->name != NULL; popt++) {
196 			/* Short-circuit if first chars don't match. */
197 			if (popt->name[0] != bsdunzip->getopt_word[0])
198 				continue;
199 			/* If option is a prefix of name in table, record it.*/
200 			if (strncmp(bsdunzip->getopt_word, popt->name, optlength) == 0) {
201 				match2 = match; /* Record up to two matches. */
202 				match = popt;
203 				/* If it's an exact match, we're done. */
204 				if (strlen(popt->name) == optlength) {
205 					match2 = NULL; /* Forget the others. */
206 					break;
207 				}
208 			}
209 		}
210 
211 		/* Fail if there wasn't a unique match. */
212 		if (match == NULL) {
213 			lafe_warnc(0,
214 			    "Option %s%s is not supported",
215 			    long_prefix, bsdunzip->getopt_word);
216 			return ('?');
217 		}
218 		if (match2 != NULL) {
219 			lafe_warnc(0,
220 			    "Ambiguous option %s%s (matches --%s and --%s)",
221 			    long_prefix, bsdunzip->getopt_word, match->name, match2->name);
222 			return ('?');
223 		}
224 
225 		/* We've found a unique match; does it need an argument? */
226 		if (match->required) {
227 			/* Argument required: get next word if necessary. */
228 			if (bsdunzip->argument == NULL) {
229 				bsdunzip->argument = *bsdunzip->argv;
230 				if (bsdunzip->argument == NULL) {
231 					lafe_warnc(0,
232 					    "Option %s%s requires an argument",
233 					    long_prefix, match->name);
234 					return ('?');
235 				}
236 				++bsdunzip->argv;
237 				--bsdunzip->argc;
238 				bsdunzip_optind++;
239 			}
240 		} else {
241 			/* Argument forbidden: fail if there is one. */
242 			if (bsdunzip->argument != NULL) {
243 				lafe_warnc(0,
244 				    "Option %s%s does not allow an argument",
245 				    long_prefix, match->name);
246 				return ('?');
247 			}
248 		}
249 		return (match->equivalent);
250 	}
251 
252 	return (opt);
253 }
254