xref: /original-bsd/lib/libc/gen/glob.c (revision 94e7bb75)
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	5.15 (Berkeley) 02/05/92";
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  * GLOB_NOMAGIC:
28  *	Same as GLOB_NOCHECK, but it will only append pattern if it did
29  *	not contain any magic characters.  [Used in csh style globbing]
30  * gl_matchc:
31  *	Number of matches in the current invocation of glob.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/stat.h>
36 #include <dirent.h>
37 #include <glob.h>
38 #include <ctype.h>
39 #include <errno.h>
40 #include <string.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 
44 #define	DOLLAR		'$'
45 #define	DOT		'.'
46 #define	EOS		'\0'
47 #define	LBRACKET	'['
48 #define	NOT		'!'
49 #define	QUESTION	'?'
50 #define	QUOTE		'\\'
51 #define	RANGE		'-'
52 #define	RBRACKET	']'
53 #define	SEP		'/'
54 #define	STAR		'*'
55 #define	TILDE		'~'
56 #define	UNDERSCORE	'_'
57 
58 #define	M_QUOTE		0x8000
59 #define	M_PROTECT	0x4000
60 #define	M_MASK		0xffff
61 #define	M_ASCII		0x00ff
62 
63 #define	CHAR(c)		((c)&M_ASCII)
64 #define	META(c)		((c)|M_QUOTE)
65 #define	M_ALL		META('*')
66 #define	M_END		META(']')
67 #define	M_NOT		META('!')
68 #define	M_ONE		META('?')
69 #define	M_RNG		META('-')
70 #define	M_SET		META('[')
71 #define	ismeta(c)	(((c)&M_QUOTE) != 0)
72 
73 typedef u_short Char;
74 
75 static int	 compare __P((const void *, const void *));
76 static void	 g_Ctoc __P((Char *, char *));
77 static int	 g_lstat __P((Char *, struct stat *));
78 static DIR	*g_opendir __P((Char *));
79 static Char	*g_strchr __P((Char *, int));
80 static int	 g_stat __P((Char *, struct stat *));
81 static int	 glob1 __P((Char *, glob_t *));
82 static int	 glob2 __P((Char *, Char *, Char *, glob_t *));
83 static int	 glob3 __P((Char *, Char *, Char *, Char *, glob_t *));
84 static int	 globextend __P((Char *, glob_t *));
85 static int	 match __P((Char *, Char *, Char *));
86 #ifdef DEBUG
87 static void	 qprintf __P((Char *));
88 #endif
89 
90 /*
91  * The main glob() routine: compiles the pattern (optionally processing
92  * quotes), calls glob1() to do the real pattern matching, and finally
93  * sorts the list (unless unsorted operation is requested).  Returns 0
94  * if things went well, nonzero if errors occurred.  It is not an error
95  * to find no matches.
96  */
97 glob(pattern, flags, errfunc, pglob)
98 	const char *pattern;
99 	int flags, (*errfunc) __P((char *, int));
100 	glob_t *pglob;
101 {
102 	const u_char *compilepat, *patnext;
103 	int c, err, oldpathc;
104 	Char *bufnext, *bufend, *compilebuf, *qpatnext, patbuf[MAXPATHLEN+1];
105 
106 	patnext = (u_char *) pattern;
107 	if (!(flags & GLOB_APPEND)) {
108 		pglob->gl_pathc = 0;
109 		pglob->gl_pathv = NULL;
110 		if (!(flags & GLOB_DOOFFS))
111 			pglob->gl_offs = 0;
112 	}
113 	pglob->gl_flags = flags & ~GLOB_MAGCHAR;
114 	pglob->gl_errfunc = errfunc;
115 	oldpathc = pglob->gl_pathc;
116 	pglob->gl_matchc = 0;
117 
118 	bufnext = patbuf;
119 	bufend = bufnext + MAXPATHLEN;
120 	compilebuf = bufnext;
121 	compilepat = patnext;
122 	if (flags & GLOB_QUOTE) {
123 		/* Protect the quoted characters. */
124 		while (bufnext < bufend && (c = *patnext++) != EOS)
125 			if (c == QUOTE) {
126 				if ((c = *patnext++) == EOS) {
127 					c = QUOTE;
128 					--patnext;
129 				}
130 				*bufnext++ = c | M_PROTECT;
131 			}
132 			else
133 				*bufnext++ = c;
134 	}
135 	else
136 	    while (bufnext < bufend && (c = *patnext++) != EOS)
137 		    *bufnext++ = c;
138 	*bufnext = EOS;
139 
140 	bufnext = patbuf;
141 	qpatnext = patbuf;
142 	/* We don't need to check for buffer overflow any more. */
143 	while ((c = *qpatnext++) != EOS) {
144 		switch (c) {
145 		case LBRACKET:
146 			c = *qpatnext;
147 			if (c == NOT)
148 				++qpatnext;
149 			if (*qpatnext == EOS ||
150 			    g_strchr(qpatnext+1, RBRACKET) == NULL) {
151 				*bufnext++ = LBRACKET;
152 				if (c == NOT)
153 					--qpatnext;
154 				break;
155 			}
156 			*bufnext++ = M_SET;
157 			if (c == NOT)
158 				*bufnext++ = M_NOT;
159 			c = *qpatnext++;
160 			do {
161 				*bufnext++ = CHAR(c);
162 				if (*qpatnext == RANGE &&
163 				    (c = qpatnext[1]) != RBRACKET) {
164 					*bufnext++ = M_RNG;
165 					*bufnext++ = CHAR(c);
166 					qpatnext += 2;
167 				}
168 			} while ((c = *qpatnext++) != RBRACKET);
169 			pglob->gl_flags |= GLOB_MAGCHAR;
170 			*bufnext++ = M_END;
171 			break;
172 		case QUESTION:
173 			pglob->gl_flags |= GLOB_MAGCHAR;
174 			*bufnext++ = M_ONE;
175 			break;
176 		case STAR:
177 			pglob->gl_flags |= GLOB_MAGCHAR;
178 			*bufnext++ = M_ALL;
179 			break;
180 		default:
181 			*bufnext++ = CHAR(c);
182 			break;
183 		}
184 	}
185 	*bufnext = EOS;
186 #ifdef DEBUG
187 	qprintf(patbuf);
188 #endif
189 
190 	if ((err = glob1(patbuf, pglob)) != 0)
191 		return(err);
192 
193 	/*
194 	 * If there was no match we are going to append the pattern
195 	 * if GLOB_NOCHECK was specified or if GLOB_NOMAGIC was specified
196 	 * and the pattern did not contain any magic characters
197 	 * GLOB_NOMAGIC is there just for compatibility with csh.
198 	 */
199 	if (pglob->gl_pathc == oldpathc &&
200 	    ((flags & GLOB_NOCHECK) ||
201 	     ((flags & GLOB_NOMAGIC) && !(pglob->gl_flags & GLOB_MAGCHAR)))) {
202 		if (!(flags & GLOB_QUOTE)) {
203 			Char *dp = compilebuf;
204 			const u_char *sp = compilepat;
205 			while (*dp++ = *sp++);
206 		}
207 		else {
208 			/*
209 			 * Copy pattern, interpreting quotes; this is slightly
210 			 * different than the interpretation of quotes above
211 			 * -- which should prevail?
212 			 */
213 			while (*compilepat != EOS) {
214 				if (*compilepat == QUOTE) {
215 					if (*++compilepat == EOS)
216 						--compilepat;
217 				}
218 				*compilebuf++ = (u_char)*compilepat++;
219 			}
220 			*compilebuf = EOS;
221 		}
222 		return(globextend(patbuf, pglob));
223 	} else if (!(flags & GLOB_NOSORT))
224 		qsort(pglob->gl_pathv + pglob->gl_offs + oldpathc,
225 		    pglob->gl_pathc - oldpathc, sizeof(char *), compare);
226 	return(0);
227 }
228 
229 static int
230 compare(p, q)
231 	const void *p, *q;
232 {
233 	return(strcmp(*(char **)p, *(char **)q));
234 }
235 
236 static
237 glob1(pattern, pglob)
238 	Char *pattern;
239 	glob_t *pglob;
240 {
241 	Char pathbuf[MAXPATHLEN+1];
242 
243 	/* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */
244 	if (*pattern == EOS)
245 		return(0);
246 	return(glob2(pathbuf, pathbuf, pattern, pglob));
247 }
248 
249 /*
250  * The functions glob2 and glob3 are mutually recursive; there is one level
251  * of recursion for each segment in the pattern that contains one or more
252  * meta characters.
253  */
254 static
255 glob2(pathbuf, pathend, pattern, pglob)
256 	Char *pathbuf, *pathend, *pattern;
257 	glob_t *pglob;
258 {
259 	struct stat sb;
260 	Char *p, *q;
261 	int anymeta;
262 
263 	/*
264 	 * Loop over pattern segments until end of pattern or until
265 	 * segment with meta character found.
266 	 */
267 	for (anymeta = 0;;) {
268 		if (*pattern == EOS) {		/* End of pattern? */
269 			*pathend = EOS;
270 			if (g_lstat(pathbuf, &sb))
271 				return(0);
272 
273 			if (((pglob->gl_flags & GLOB_MARK) &&
274 			    pathend[-1] != SEP) && (S_ISDIR(sb.st_mode)
275 			    || (S_ISLNK(sb.st_mode) &&
276 			    (g_stat(pathbuf, &sb) == 0) &&
277 			    S_ISDIR(sb.st_mode)))) {
278 				*pathend++ = SEP;
279 				*pathend = EOS;
280 			}
281 			++pglob->gl_matchc;
282 			return(globextend(pathbuf, pglob));
283 		}
284 
285 		/* Find end of next segment, copy tentatively to pathend. */
286 		q = pathend;
287 		p = pattern;
288 		while (*p != EOS && *p != SEP) {
289 			if (ismeta(*p))
290 				anymeta = 1;
291 			*q++ = *p++;
292 		}
293 
294 		if (!anymeta) {		/* No expansion, do next segment. */
295 			pathend = q;
296 			pattern = p;
297 			while (*pattern == SEP)
298 				*pathend++ = *pattern++;
299 		} else			/* Need expansion, recurse. */
300 			return(glob3(pathbuf, pathend, pattern, p, pglob));
301 	}
302 	/* NOTREACHED */
303 }
304 
305 static
306 glob3(pathbuf, pathend, pattern, restpattern, pglob)
307 	Char *pathbuf, *pathend, *pattern, *restpattern;
308 	glob_t *pglob;
309 {
310 	register struct dirent *dp;
311 	DIR *dirp;
312 	int len, err;
313 
314 	*pathend = EOS;
315 	errno = 0;
316 
317 	if (!(dirp = g_opendir(pathbuf)))
318 		/* TODO: don't call for ENOENT or ENOTDIR? */
319 		if (pglob->gl_errfunc &&
320 		    (*pglob->gl_errfunc)(pathbuf, errno) ||
321 		    (pglob->gl_flags & GLOB_ERR))
322 			return(GLOB_ABEND);
323 		else
324 			return(0);
325 
326 	err = 0;
327 
328 	/* Search directory for matching names. */
329 	while ((dp = readdir(dirp))) {
330 		register u_char *sc;
331 		register Char *dc;
332 
333 		/* Initial DOT must be matched literally. */
334 		if (dp->d_name[0] == DOT && *pattern != DOT)
335 			continue;
336 		for (sc = (u_char *) dp->d_name, dc = pathend;
337 		     *dc++ = *sc++;);
338 		if (!match(pathend, pattern, restpattern)) {
339 			*pathend = EOS;
340 			continue;
341 		}
342 		err = glob2(pathbuf, --dc, restpattern, pglob);
343 		if (err)
344 			break;
345 	}
346 
347 	/* TODO: check error from readdir? */
348 	(void)closedir(dirp);
349 	return(err);
350 }
351 
352 
353 /*
354  * Extend the gl_pathv member of a glob_t structure to accomodate a new item,
355  * add the new item, and update gl_pathc.
356  *
357  * This assumes the BSD realloc, which only copies the block when its size
358  * crosses a power-of-two boundary; for v7 realloc, this would cause quadratic
359  * behavior.
360  *
361  * Return 0 if new item added, error code if memory couldn't be allocated.
362  *
363  * Invariant of the glob_t structure:
364  *	Either gl_pathc is zero and gl_pathv is NULL; or gl_pathc > 0 and
365  *	gl_pathv points to (gl_offs + gl_pathc + 1) items.
366  */
367 static int
368 globextend(path, pglob)
369 	Char *path;
370 	glob_t *pglob;
371 {
372 	register char **pathv;
373 	register int i;
374 	u_int newsize;
375 	char *copy;
376 	Char *p;
377 
378 	newsize = sizeof(*pathv) * (2 + pglob->gl_pathc + pglob->gl_offs);
379 	pathv = (char **)realloc((char *)pglob->gl_pathv, newsize);
380 	if (pathv == NULL)
381 		return(GLOB_NOSPACE);
382 
383 	if (pglob->gl_pathv == NULL && pglob->gl_offs > 0) {
384 		/* first time around -- clear initial gl_offs items */
385 		pathv += pglob->gl_offs;
386 		for (i = pglob->gl_offs; --i >= 0; )
387 			*--pathv = NULL;
388 	}
389 	pglob->gl_pathv = pathv;
390 
391 	for (p = path; *p++;);
392 	if ((copy = malloc(p - path)) != NULL) {
393 		g_Ctoc(path, copy);
394 		pathv[pglob->gl_offs + pglob->gl_pathc++] = copy;
395 	}
396 	pathv[pglob->gl_offs + pglob->gl_pathc] = NULL;
397 	return(copy == NULL ? GLOB_NOSPACE : 0);
398 }
399 
400 
401 /*
402  * pattern matching function for filenames.  Each occurrence of the *
403  * pattern causes a recursion level.
404  */
405 static
406 match(name, pat, patend)
407 	register Char *name, *pat, *patend;
408 {
409 	int ok, negate_range;
410 	Char c, k;
411 
412 	while (pat < patend) {
413 		c = *pat++;
414 		switch (c & M_MASK) {
415 		case M_ALL:
416 			if (pat == patend)
417 				return(1);
418 			for (; *name != EOS; ++name)
419 				if (match(name, pat, patend))
420 					return(1);
421 			return(0);
422 		case M_ONE:
423 			if (*name++ == EOS)
424 				return(0);
425 			break;
426 		case M_SET:
427 			ok = 0;
428 			if ((k = *name++) == EOS)
429 				return(0);
430 			if (negate_range = ((*pat & M_MASK) == M_NOT))
431 				++pat;
432 			while (((c = *pat++) & M_MASK) != M_END)
433 				if ((*pat & M_MASK) == M_RNG) {
434 					if (c <= k && k <= pat[1])
435 						ok = 1;
436 					pat += 2;
437 				} else if (c == k)
438 					ok = 1;
439 			if (ok == negate_range)
440 				return(0);
441 			break;
442 		default:
443 			if (*name++ != c)
444 				return(0);
445 			break;
446 		}
447 	}
448 	return(*name == EOS);
449 }
450 
451 /* Free allocated data belonging to a glob_t structure. */
452 void
453 globfree(pglob)
454 	glob_t *pglob;
455 {
456 	register int i;
457 	register char **pp;
458 
459 	if (pglob->gl_pathv != NULL) {
460 		pp = pglob->gl_pathv + pglob->gl_offs;
461 		for (i = pglob->gl_pathc; i--; ++pp)
462 			if (*pp)
463 				free(*pp);
464 		free(pglob->gl_pathv);
465 	}
466 }
467 
468 static DIR *
469 g_opendir(str)
470 	register Char *str;
471 {
472 	char buf[MAXPATHLEN];
473 
474 	if (!*str)
475 		return(opendir("."));
476 	g_Ctoc(str, buf);
477 	return(opendir(buf));
478 }
479 
480 static int
481 g_lstat(fn, sb)
482 	register Char *fn;
483 	struct stat *sb;
484 {
485 	char buf[MAXPATHLEN];
486 
487 	g_Ctoc(fn, buf);
488 	return(lstat(buf, sb));
489 }
490 
491 static int
492 g_stat(fn, sb)
493 	register Char *fn;
494 	struct stat *sb;
495 {
496 	char buf[MAXPATHLEN];
497 
498 	g_Ctoc(fn, buf);
499 	return(stat(buf, sb));
500 }
501 
502 static Char *
503 g_strchr(str, ch)
504 	Char *str;
505 	int ch;
506 {
507 	do {
508 		if (*str == ch)
509 			return (str);
510 	} while (*str++);
511 	return (NULL);
512 }
513 
514 static void
515 g_Ctoc(str, buf)
516 	register Char *str;
517 	char *buf;
518 {
519 	register char *dc;
520 
521 	for (dc = buf; *dc++ = *str++;);
522 }
523 
524 #ifdef DEBUG
525 static void
526 qprintf(s)
527 	register Char *s;
528 {
529 	register Char *p;
530 
531 	for (p = s; *p; p++)
532 		(void)printf("%c", *p & 0xff);
533 	(void)printf("\n");
534 	for (p = s; *p; p++)
535 		(void)printf("%c", *p & M_PROTECT ? '"' : ' ');
536 	(void)printf("\n");
537 	for (p = s; *p; p++)
538 		(void)printf("%c", *p & M_META ? '_' : ' ');
539 	(void)printf("\n");
540 }
541 #endif
542