fnmatch.c revision 304275
1/*
2 * Copyright (c) 1989, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Guido van Rossum.
7 *
8 * Copyright (c) 2011 The FreeBSD Foundation
9 * All rights reserved.
10 * Portions of this software were developed by David Chisnall
11 * under sponsorship from the FreeBSD Foundation.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38#if defined(LIBC_SCCS) && !defined(lint)
39static char sccsid[] = "@(#)fnmatch.c	8.2 (Berkeley) 4/16/94";
40#endif /* LIBC_SCCS and not lint */
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD: stable/11/lib/libc/gen/fnmatch.c 304275 2016-08-17 08:51:47Z ache $");
43
44/*
45 * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
46 * Compares a filename or pathname to a pattern.
47 */
48
49/*
50 * Some notes on multibyte character support:
51 * 1. Patterns with illegal byte sequences match nothing.
52 * 2. Illegal byte sequences in the "string" argument are handled by treating
53 *    them as single-byte characters with a value of the first byte of the
54 *    sequence cast to wchar_t.
55 * 3. Multibyte conversion state objects (mbstate_t) are passed around and
56 *    used for most, but not all, conversions. Further work will be required
57 *    to support state-dependent encodings.
58 */
59
60#include <fnmatch.h>
61#include <limits.h>
62#include <string.h>
63#include <wchar.h>
64#include <wctype.h>
65
66#include "collate.h"
67
68#define	EOS	'\0'
69
70#define RANGE_MATCH     1
71#define RANGE_NOMATCH   0
72#define RANGE_ERROR     (-1)
73
74static int rangematch(const char *, wchar_t, int, char **, mbstate_t *);
75static int fnmatch1(const char *, const char *, const char *, int, mbstate_t,
76		mbstate_t);
77
78int
79fnmatch(const char *pattern, const char *string, int flags)
80{
81	static const mbstate_t initial;
82
83	return (fnmatch1(pattern, string, string, flags, initial, initial));
84}
85
86static int
87fnmatch1(const char *pattern, const char *string, const char *stringstart,
88    int flags, mbstate_t patmbs, mbstate_t strmbs)
89{
90	const char *bt_pattern, *bt_string;
91	mbstate_t bt_patmbs, bt_strmbs;
92	char *newp;
93	char c;
94	wchar_t pc, sc;
95	size_t pclen, sclen;
96
97	bt_pattern = bt_string = NULL;
98	for (;;) {
99		pclen = mbrtowc(&pc, pattern, MB_LEN_MAX, &patmbs);
100		if (pclen == (size_t)-1 || pclen == (size_t)-2)
101			return (FNM_NOMATCH);
102		pattern += pclen;
103		sclen = mbrtowc(&sc, string, MB_LEN_MAX, &strmbs);
104		if (sclen == (size_t)-1 || sclen == (size_t)-2) {
105			sc = (unsigned char)*string;
106			sclen = 1;
107			memset(&strmbs, 0, sizeof(strmbs));
108		}
109		switch (pc) {
110		case EOS:
111			if ((flags & FNM_LEADING_DIR) && sc == '/')
112				return (0);
113			if (sc == EOS)
114				return (0);
115			goto backtrack;
116		case '?':
117			if (sc == EOS)
118				return (FNM_NOMATCH);
119			if (sc == '/' && (flags & FNM_PATHNAME))
120				goto backtrack;
121			if (sc == '.' && (flags & FNM_PERIOD) &&
122			    (string == stringstart ||
123			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
124				goto backtrack;
125			string += sclen;
126			break;
127		case '*':
128			c = *pattern;
129			/* Collapse multiple stars. */
130			while (c == '*')
131				c = *++pattern;
132
133			if (sc == '.' && (flags & FNM_PERIOD) &&
134			    (string == stringstart ||
135			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
136				goto backtrack;
137
138			/* Optimize for pattern with * at end or before /. */
139			if (c == EOS)
140				if (flags & FNM_PATHNAME)
141					return ((flags & FNM_LEADING_DIR) ||
142					    strchr(string, '/') == NULL ?
143					    0 : FNM_NOMATCH);
144				else
145					return (0);
146			else if (c == '/' && flags & FNM_PATHNAME) {
147				if ((string = strchr(string, '/')) == NULL)
148					return (FNM_NOMATCH);
149				break;
150			}
151
152			/*
153			 * First try the shortest match for the '*' that
154			 * could work. We can forget any earlier '*' since
155			 * there is no way having it match more characters
156			 * can help us, given that we are already here.
157			 */
158			bt_pattern = pattern, bt_patmbs = patmbs;
159			bt_string = string, bt_strmbs = strmbs;
160			break;
161		case '[':
162			if (sc == EOS)
163				return (FNM_NOMATCH);
164			if (sc == '/' && (flags & FNM_PATHNAME))
165				goto backtrack;
166			if (sc == '.' && (flags & FNM_PERIOD) &&
167			    (string == stringstart ||
168			    ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
169				goto backtrack;
170
171			switch (rangematch(pattern, sc, flags, &newp,
172			    &patmbs)) {
173			case RANGE_ERROR:
174				goto norm;
175			case RANGE_MATCH:
176				pattern = newp;
177				break;
178			case RANGE_NOMATCH:
179				goto backtrack;
180			}
181			string += sclen;
182			break;
183		case '\\':
184			if (!(flags & FNM_NOESCAPE)) {
185				pclen = mbrtowc(&pc, pattern, MB_LEN_MAX,
186				    &patmbs);
187				if (pclen == (size_t)-1 || pclen == (size_t)-2)
188					return (FNM_NOMATCH);
189				pattern += pclen;
190			}
191			/* FALLTHROUGH */
192		default:
193		norm:
194			string += sclen;
195			if (pc == sc)
196				;
197			else if ((flags & FNM_CASEFOLD) &&
198				 (towlower(pc) == towlower(sc)))
199				;
200			else {
201		backtrack:
202				/*
203				 * If we have a mismatch (other than hitting
204				 * the end of the string), go back to the last
205				 * '*' seen and have it match one additional
206				 * character.
207				 */
208				if (bt_pattern == NULL)
209					return (FNM_NOMATCH);
210				sclen = mbrtowc(&sc, bt_string, MB_LEN_MAX,
211				    &bt_strmbs);
212				if (sclen == (size_t)-1 ||
213				    sclen == (size_t)-2) {
214					sc = (unsigned char)*bt_string;
215					sclen = 1;
216					memset(&bt_strmbs, 0,
217					    sizeof(bt_strmbs));
218				}
219				if (sc == EOS)
220					return (FNM_NOMATCH);
221				if (sc == '/' && flags & FNM_PATHNAME)
222					return (FNM_NOMATCH);
223				bt_string += sclen;
224				pattern = bt_pattern, patmbs = bt_patmbs;
225				string = bt_string, strmbs = bt_strmbs;
226			}
227			break;
228		}
229	}
230	/* NOTREACHED */
231}
232
233static int
234rangematch(const char *pattern, wchar_t test, int flags, char **newp,
235    mbstate_t *patmbs)
236{
237	int negate, ok;
238	wchar_t c, c2;
239	size_t pclen;
240	const char *origpat;
241	struct xlocale_collate *table =
242		(struct xlocale_collate*)__get_locale()->components[XLC_COLLATE];
243
244	/*
245	 * A bracket expression starting with an unquoted circumflex
246	 * character produces unspecified results (IEEE 1003.2-1992,
247	 * 3.13.2).  This implementation treats it like '!', for
248	 * consistency with the regular expression syntax.
249	 * J.T. Conklin (conklin@ngai.kaleida.com)
250	 */
251	if ( (negate = (*pattern == '!' || *pattern == '^')) )
252		++pattern;
253
254	if (flags & FNM_CASEFOLD)
255		test = towlower(test);
256
257	/*
258	 * A right bracket shall lose its special meaning and represent
259	 * itself in a bracket expression if it occurs first in the list.
260	 * -- POSIX.2 2.8.3.2
261	 */
262	ok = 0;
263	origpat = pattern;
264	for (;;) {
265		if (*pattern == ']' && pattern > origpat) {
266			pattern++;
267			break;
268		} else if (*pattern == '\0') {
269			return (RANGE_ERROR);
270		} else if (*pattern == '/' && (flags & FNM_PATHNAME)) {
271			return (RANGE_NOMATCH);
272		} else if (*pattern == '\\' && !(flags & FNM_NOESCAPE))
273			pattern++;
274		pclen = mbrtowc(&c, pattern, MB_LEN_MAX, patmbs);
275		if (pclen == (size_t)-1 || pclen == (size_t)-2)
276			return (RANGE_NOMATCH);
277		pattern += pclen;
278
279		if (flags & FNM_CASEFOLD)
280			c = towlower(c);
281
282		if (*pattern == '-' && *(pattern + 1) != EOS &&
283		    *(pattern + 1) != ']') {
284			if (*++pattern == '\\' && !(flags & FNM_NOESCAPE))
285				if (*pattern != EOS)
286					pattern++;
287			pclen = mbrtowc(&c2, pattern, MB_LEN_MAX, patmbs);
288			if (pclen == (size_t)-1 || pclen == (size_t)-2)
289				return (RANGE_NOMATCH);
290			pattern += pclen;
291			if (c2 == EOS)
292				return (RANGE_ERROR);
293
294			if (flags & FNM_CASEFOLD)
295				c2 = towlower(c2);
296
297			if (table->__collate_load_error ?
298			    c <= test && test <= c2 :
299			       __wcollate_range_cmp(c, test) <= 0
300			    && __wcollate_range_cmp(test, c2) <= 0
301			   )
302				ok = 1;
303		} else if (c == test)
304			ok = 1;
305	}
306
307	*newp = (char *)pattern;
308	return (ok == negate ? RANGE_NOMATCH : RANGE_MATCH);
309}
310