xref: /csrg-svn/lib/libc/gen/glob.c (revision 50117)
1 /*
2  * Copyright (c) 1989 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Guido van Rossum.
7  *
8  * %sccs.include.redist.c%
9  */
10 
11 #if defined(LIBC_SCCS) && !defined(lint)
12 static char sccsid[] = "@(#)glob.c	5.11 (Berkeley) 06/23/91";
13 #endif /* LIBC_SCCS and not lint */
14 
15 /*
16  * glob(3) -- a superset of the one defined in POSIX 1003.2.
17  *
18  * The [!...] convention to negate a range is supported (SysV, Posix, ksh).
19  *
20  * Optional extra services, controlled by flags not defined by POSIX:
21  *
22  * GLOB_QUOTE:
23  *	Escaping convention: \ inhibits any special meaning the following
24  *	character might have (except \ at end of string is retained).
25  * GLOB_MAGCHAR:
26  *	Set in gl_flags if pattern contained a globbing character.
27  * gl_matchc:
28  *	Number of matches in the current invocation of glob.
29  */
30 
31 #include <sys/cdefs.h>
32 #include <sys/param.h>
33 #include <sys/stat.h>
34 #include <dirent.h>
35 #include <glob.h>
36 #include <ctype.h>
37 #include <errno.h>
38 #include <string.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 
42 #define	DOLLAR		'$'
43 #define	DOT		'.'
44 #define	EOS		'\0'
45 #define	LBRACKET	'['
46 #define	NOT		'!'
47 #define	QUESTION	'?'
48 #define	QUOTE		'\\'
49 #define	RANGE		'-'
50 #define	RBRACKET	']'
51 #define	SEP		'/'
52 #define	STAR		'*'
53 #define	TILDE		'~'
54 #define	UNDERSCORE	'_'
55 
56 #define	M_QUOTE		0x8000
57 #define	M_PROTECT	0x4000
58 #define	M_MASK		0xffff
59 
60 #define	META(c)		((c)|M_QUOTE)
61 #define	M_ALL		META('*')
62 #define	M_END		META(']')
63 #define	M_NOT		META('!')
64 #define	M_ONE		META('?')
65 #define	M_RNG		META('-')
66 #define	M_SET		META('[')
67 #define	ismeta(c)	(((c)&M_QUOTE) != 0)
68 
69 typedef u_short Char;
70 
71 static int	 compare __P((const void *, const void *));
72 static void	 g_Ctoc __P((Char *, char *));
73 static int	 g_lstat __P((Char *, struct stat *));
74 static DIR	*g_opendir __P((Char *));
75 static Char	*g_strchr __P((Char *, int));
76 static int	 g_stat __P((Char *, struct stat *));
77 static int	 glob1 __P((Char *, glob_t *));
78 static int	 glob2 __P((Char *, Char *, Char *, glob_t *));
79 static int	 glob3 __P((Char *, Char *, Char *, Char *, glob_t *));
80 static int	 globextend __P((Char *, glob_t *));
81 static int	 match __P((Char *, Char *, Char *));
82 #ifdef DEBUG
83 static void	 qprintf __P((Char *));
84 #endif
85 
86 /*
87  * The main glob() routine: compiles the pattern (optionally processing
88  * quotes), calls glob1() to do the real pattern matching, and finally
89  * sorts the list (unless unsorted operation is requested).  Returns 0
90  * if things went well, nonzero if errors occurred.  It is not an error
91  * to find no matches.
92  */
93 glob(pattern, flags, errfunc, pglob)
94 	const char *pattern;
95 	int flags, (*errfunc) __P((char *, int));
96 	glob_t *pglob;
97 {
98 	const char *compilepat, *patnext;
99 	int c, err, oldpathc;
100 	Char *bufnext, *bufend, *compilebuf, *qpatnext, patbuf[MAXPATHLEN+1];
101 
102 	patnext = pattern;
103 	if (!(flags & GLOB_APPEND)) {
104 		pglob->gl_pathc = 0;
105 		pglob->gl_pathv = NULL;
106 		if (!(flags & GLOB_DOOFFS))
107 			pglob->gl_offs = 0;
108 	}
109 	pglob->gl_flags = flags & ~GLOB_MAGCHAR;
110 	pglob->gl_errfunc = errfunc;
111 	oldpathc = pglob->gl_pathc;
112 	pglob->gl_matchc = 0;
113 
114 	bufnext = patbuf;
115 	bufend = bufnext + MAXPATHLEN;
116 	compilebuf = bufnext;
117 	compilepat = patnext;
118 	if (flags & GLOB_QUOTE) {
119 		/* Protect the quoted characters. */
120 		while (bufnext < bufend && (c = *patnext++) != EOS)
121 			if (c == QUOTE) {
122 				if ((c = *patnext++) == EOS) {
123 					c = QUOTE;
124 					--patnext;
125 				}
126 				*bufnext++ = c | M_PROTECT;
127 			}
128 			else
129 				*bufnext++ = c;
130 	}
131 	else
132 	    while (bufnext < bufend && (c = *patnext++) != EOS)
133 		    *bufnext++ = c;
134 	*bufnext = EOS;
135 
136 	bufnext = patbuf;
137 	qpatnext = patbuf;
138 	/* We don't need to check for buffer overflow any more. */
139 	while ((c = *qpatnext++) != EOS) {
140 		switch (c) {
141 		case LBRACKET:
142 			pglob->gl_flags |= GLOB_MAGCHAR;
143 			c = *qpatnext;
144 			if (c == NOT)
145 				++qpatnext;
146 			if (*qpatnext == EOS ||
147 			    g_strchr(qpatnext+1, RBRACKET) == NULL) {
148 				*bufnext++ = LBRACKET;
149 				if (c == NOT)
150 					--qpatnext;
151 				break;
152 			}
153 			*bufnext++ = M_SET;
154 			if (c == NOT)
155 				*bufnext++ = M_NOT;
156 			c = *qpatnext++;
157 			do {
158 				*bufnext++ = c;
159 				if (*qpatnext == RANGE &&
160 				    (c = qpatnext[1]) != RBRACKET) {
161 					*bufnext++ = M_RNG;
162 					*bufnext++ = c;
163 					qpatnext += 2;
164 				}
165 			} while ((c = *qpatnext++) != RBRACKET);
166 			*bufnext++ = M_END;
167 			break;
168 		case QUESTION:
169 			pglob->gl_flags |= GLOB_MAGCHAR;
170 			*bufnext++ = M_ONE;
171 			break;
172 		case STAR:
173 			pglob->gl_flags |= GLOB_MAGCHAR;
174 			*bufnext++ = M_ALL;
175 			break;
176 		default:
177 			*bufnext++ = c;
178 			break;
179 		}
180 	}
181 	*bufnext = EOS;
182 #ifdef DEBUG
183 	qprintf(patbuf);
184 #endif
185 
186 	if ((err = glob1(patbuf, pglob)) != 0)
187 		return(err);
188 
189 	if (pglob->gl_pathc == oldpathc && flags & GLOB_NOCHECK) {
190 		if (!(flags & GLOB_QUOTE)) {
191 			Char *dp = compilebuf;
192 			const char *sp = compilepat;
193 			while (*dp++ = (u_char)*sp++);
194 		}
195 		else {
196 			/*
197 			 * Copy pattern, interpreting quotes; this is slightly
198 			 * different than the interpretation of quotes above
199 			 * -- which should prevail?
200 			 */
201 			while (*compilepat != EOS) {
202 				if (*compilepat == QUOTE) {
203 					if (*++compilepat == EOS)
204 						--compilepat;
205 				}
206 				*compilebuf++ = (u_char)*compilepat++;
207 			}
208 			*compilebuf = EOS;
209 		}
210 		return(globextend(patbuf, pglob));
211 	} else if (!(flags & GLOB_NOSORT))
212 		qsort(pglob->gl_pathv + pglob->gl_offs + oldpathc,
213 		    pglob->gl_pathc - oldpathc, sizeof(char *), compare);
214 	return(0);
215 }
216 
217 static int
218 compare(p, q)
219 	const void *p, *q;
220 {
221 	return(strcmp(*(char **)p, *(char **)q));
222 }
223 
224 static
225 glob1(pattern, pglob)
226 	Char *pattern;
227 	glob_t *pglob;
228 {
229 	Char pathbuf[MAXPATHLEN+1];
230 
231 	/* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */
232 	if (*pattern == EOS)
233 		return(0);
234 	return(glob2(pathbuf, pathbuf, pattern, pglob));
235 }
236 
237 /*
238  * The functions glob2 and glob3 are mutually recursive; there is one level
239  * of recursion for each segment in the pattern that contains one or more
240  * meta characters.
241  */
242 static
243 glob2(pathbuf, pathend, pattern, pglob)
244 	Char *pathbuf, *pathend, *pattern;
245 	glob_t *pglob;
246 {
247 	struct stat sb;
248 	Char *p, *q;
249 	int anymeta;
250 
251 	/*
252 	 * Loop over pattern segments until end of pattern or until
253 	 * segment with meta character found.
254 	 */
255 	for (anymeta = 0;;) {
256 		if (*pattern == EOS) {		/* End of pattern? */
257 			*pathend = EOS;
258 			if (g_stat(pathbuf, &sb))
259 				return(0);
260 
261 			if (((pglob->gl_flags & GLOB_MARK) &&
262 			    pathend[-1] != SEP) && (S_ISDIR(sb.st_mode)
263 			    || (S_ISLNK(sb.st_mode) &&
264 			    (g_stat(pathbuf, &sb) == 0) &&
265 			    S_ISDIR(sb.st_mode)))) {
266 				*pathend++ = SEP;
267 				*pathend = EOS;
268 			}
269 			++pglob->gl_matchc;
270 			return(globextend(pathbuf, pglob));
271 		}
272 
273 		/* Find end of next segment, copy tentatively to pathend. */
274 		q = pathend;
275 		p = pattern;
276 		while (*p != EOS && *p != SEP) {
277 			if (ismeta(*p))
278 				anymeta = 1;
279 			*q++ = *p++;
280 		}
281 
282 		if (!anymeta) {		/* No expansion, do next segment. */
283 			pathend = q;
284 			pattern = p;
285 			while (*pattern == SEP)
286 				*pathend++ = *pattern++;
287 		} else			/* Need expansion, recurse. */
288 			return(glob3(pathbuf, pathend, pattern, p, pglob));
289 	}
290 	/* NOTREACHED */
291 }
292 
293 static
294 glob3(pathbuf, pathend, pattern, restpattern, pglob)
295 	Char *pathbuf, *pathend, *pattern, *restpattern;
296 	glob_t *pglob;
297 {
298 	register struct dirent *dp;
299 	DIR *dirp;
300 	int len, err;
301 
302 	*pathend = EOS;
303 	errno = 0;
304 
305 	if (!(dirp = g_opendir(pathbuf)))
306 		/* TODO: don't call for ENOENT or ENOTDIR? */
307 		if (pglob->gl_errfunc &&
308 		    (*pglob->gl_errfunc)(pathbuf, errno) ||
309 		    (pglob->gl_flags & GLOB_ERR))
310 			return(GLOB_ABEND);
311 		else
312 			return(0);
313 
314 	err = 0;
315 
316 	/* Search directory for matching names. */
317 	while ((dp = readdir(dirp))) {
318 		register char *sc;
319 		register Char *dc;
320 
321 		/* Initial DOT must be matched literally. */
322 		if (dp->d_name[0] == DOT && *pattern != DOT)
323 			continue;
324 		for (sc = dp->d_name, dc = pathend;
325 		     *dc++ = (u_char)*sc++;);
326 		if (!match(pathend, pattern, restpattern)) {
327 			*pathend = EOS;
328 			continue;
329 		}
330 		err = glob2(pathbuf, --dc, restpattern, pglob);
331 		if (err)
332 			break;
333 	}
334 
335 	/* TODO: check error from readdir? */
336 	(void)closedir(dirp);
337 	return(err);
338 }
339 
340 
341 /*
342  * Extend the gl_pathv member of a glob_t structure to accomodate a new item,
343  * add the new item, and update gl_pathc.
344  *
345  * This assumes the BSD realloc, which only copies the block when its size
346  * crosses a power-of-two boundary; for v7 realloc, this would cause quadratic
347  * behavior.
348  *
349  * Return 0 if new item added, error code if memory couldn't be allocated.
350  *
351  * Invariant of the glob_t structure:
352  *	Either gl_pathc is zero and gl_pathv is NULL; or gl_pathc > 0 and
353  *	gl_pathv points to (gl_offs + gl_pathc + 1) items.
354  */
355 static int
356 globextend(path, pglob)
357 	Char *path;
358 	glob_t *pglob;
359 {
360 	register char **pathv;
361 	register int i;
362 	u_int newsize;
363 	char *copy;
364 	Char *p;
365 
366 	newsize = sizeof(*pathv) * (2 + pglob->gl_pathc + pglob->gl_offs);
367 	pathv = (char **)realloc((char *)pglob->gl_pathv, newsize);
368 	if (pathv == NULL)
369 		return(GLOB_NOSPACE);
370 
371 	if (pglob->gl_pathv == NULL && pglob->gl_offs > 0) {
372 		/* first time around -- clear initial gl_offs items */
373 		pathv += pglob->gl_offs;
374 		for (i = pglob->gl_offs; --i >= 0; )
375 			*--pathv = NULL;
376 	}
377 	pglob->gl_pathv = pathv;
378 
379 	for (p = path; *p++;);
380 	if ((copy = malloc(p - path)) != NULL) {
381 		g_Ctoc(path, copy);
382 		pathv[pglob->gl_offs + pglob->gl_pathc++] = copy;
383 	}
384 	pathv[pglob->gl_offs + pglob->gl_pathc] = NULL;
385 	return(copy == NULL ? GLOB_NOSPACE : 0);
386 }
387 
388 
389 /*
390  * pattern matching function for filenames.  Each occurrence of the *
391  * pattern causes a recursion level.
392  */
393 static
394 match(name, pat, patend)
395 	register Char *name, *pat, *patend;
396 {
397 	int ok, negate_range;
398 	Char c, k;
399 
400 	while (pat < patend) {
401 		c = *pat++;
402 		switch (c & M_MASK) {
403 		case M_ALL:
404 			if (pat == patend)
405 				return(1);
406 			for (; *name != EOS; ++name)
407 				if (match(name, pat, patend))
408 					return(1);
409 			return(0);
410 		case M_ONE:
411 			if (*name++ == EOS)
412 				return(0);
413 			break;
414 		case M_SET:
415 			ok = 0;
416 			k = *name++;
417 			if (negate_range = ((*pat & M_MASK) == M_NOT))
418 				++pat;
419 			while (((c = *pat++) & M_MASK) != M_END)
420 				if ((*pat & M_MASK) == M_RNG) {
421 					if (c <= k && k <= pat[1])
422 						ok = 1;
423 					pat += 2;
424 				} else if (c == k)
425 					ok = 1;
426 			if (ok == negate_range)
427 				return(0);
428 			break;
429 		default:
430 			if (*name++ != c)
431 				return(0);
432 			break;
433 		}
434 	}
435 	return(*name == EOS);
436 }
437 
438 /* Free allocated data belonging to a glob_t structure. */
439 void
440 globfree(pglob)
441 	glob_t *pglob;
442 {
443 	register int i;
444 	register char **pp;
445 
446 	if (pglob->gl_pathv != NULL) {
447 		pp = pglob->gl_pathv + pglob->gl_offs;
448 		for (i = pglob->gl_pathc; i--; ++pp)
449 			if (*pp)
450 				free(*pp);
451 		free(pglob->gl_pathv);
452 	}
453 }
454 
455 static DIR *
456 g_opendir(str)
457 	register Char *str;
458 {
459 	char buf[MAXPATHLEN];
460 
461 	if (!*str)
462 		return(opendir("."));
463 	g_Ctoc(str, buf);
464 	return(opendir(buf));
465 }
466 
467 static int
468 g_lstat(fn, sb)
469 	register Char *fn;
470 	struct stat *sb;
471 {
472 	char buf[MAXPATHLEN];
473 
474 	g_Ctoc(fn, buf);
475 	return(lstat(buf, sb));
476 }
477 
478 static int
479 g_stat(fn, sb)
480 	register Char *fn;
481 	struct stat *sb;
482 {
483 	char buf[MAXPATHLEN];
484 
485 	g_Ctoc(fn, buf);
486 	return(stat(buf, sb));
487 }
488 
489 static Char *
490 g_strchr(str, ch)
491 	Char *str;
492 	int ch;
493 {
494 	do {
495 		if (*str == ch)
496 			return (str);
497 	} while (*str++);
498 	return (NULL);
499 }
500 
501 static void
502 g_Ctoc(str, buf)
503 	register Char *str;
504 	char *buf;
505 {
506 	register char *dc;
507 
508 	for (dc = buf; *dc++ = *str++;);
509 }
510 
511 #ifdef DEBUG
512 static void
513 qprintf(s)
514 	register Char *s;
515 {
516 	register Char *p;
517 
518 	for (p = s; *p; p++)
519 		(void)printf("%c", *p & 0xff);
520 	(void)printf("\n");
521 	for (p = s; *p; p++)
522 		(void)printf("%c", *p & M_PROTECT ? '"' : ' ');
523 	(void)printf("\n");
524 	for (p = s; *p; p++)
525 		(void)printf("%c", *p & M_META ? '_' : ' ');
526 	(void)printf("\n");
527 }
528 #endif
529