xref: /freebsd/lib/libc/gen/fts-compat15.c (revision 4bd01d6ae01632501b63438b8d9a401db9744a78)
1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  */
32 /*
33  * Compatibility shim for FBSD_1.5 fts(3) ABI.
34  * This file provides the old fts functions for binaries compiled
35  * against FreeBSD 15.x and earlier without fts_dirfd in FTSENT15.
36  */
37 
38 #include "namespace.h"
39 #include <sys/param.h>
40 #include <sys/mount.h>
41 #include <sys/stat.h>
42 
43 #include <dirent.h>
44 #include <errno.h>
45 #include <fcntl.h>
46 #include "fts-compat15.h"
47 #include <fts.h>
48 #include <stdalign.h>
49 #include <stdint.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 #include "un-namespace.h"
54 
55 #include "gen-private.h"
56 
57 #ifdef __BLOCKS__
58 #include <Block.h>
59 #else
60 #include "block_abi.h"
61 typedef DECLARE_BLOCK(int, fts_block,
62     const FTSENT15 * const *, const FTSENT15 * const *);
63 void qsort_b(void *, size_t, size_t, fts_block);
64 #endif /* __BLOCKS__ */
65 /* only present if linked with blocks runtime */
66 void *_Block_copy(const void *) __weak_symbol;
67 void _Block_release(const void *) __weak_symbol;
68 extern void *_NSConcreteGlobalBlock[] __weak_symbol;
69 
70 static FTSENT15	*fts_alloc(FTS15 *, char *, size_t);
71 static FTSENT15	*fts_build(FTS15 *, int);
72 static void	 fts_lfree(FTSENT15 *);
73 static void	 fts_load(FTS15 *, FTSENT15 *);
74 static size_t	 fts_maxarglen(char * const *);
75 static void	 fts_padjust(FTS15 *, FTSENT15 *);
76 static int	 fts_palloc(FTS15 *, size_t);
77 static FTSENT15	*fts_sort(FTS15 *, FTSENT15 *, size_t);
78 static int	 fts_stat(FTS15 *, FTSENT15 *, int, int);
79 static int	 fts_safe_changedir(FTS15 *, FTSENT15 *, int, char *);
80 static int	 fts_ufslinks(FTS15 *, const FTSENT15 *);
81 
82 #define	ISDOT(a)	(a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
83 
84 #define	CLR(opt)	(sp->fts_options &= ~(opt))
85 #define	ISSET(opt)	(sp->fts_options & (opt))
86 #define	SET(opt)	(sp->fts_options |= (opt))
87 
88 #define	FCHDIR(sp, fd)	(!ISSET(FTS_NOCHDIR) && fchdir(fd))
89 
90 /* fts_build flags */
91 #define	BCHILD		1		/* freebsd15_fts_children */
92 #define	BNAMES		2		/* freebsd15_fts_children, names only */
93 #define	BREAD		3		/* freebsd15_fts_read */
94 
95 /*
96  * Internal representation of an FTS15, including extra implementation
97  * details.  The FTS15 returned from freebsd15_fts_open points to this structure's
98  * ftsp_fts member (and can be cast to an _fts_private as required)
99  */
100 struct _fts_private {
101 	FTS15		ftsp_fts;
102 	struct statfs	ftsp_statfs;
103 	dev_t		ftsp_dev;
104 	int		ftsp_linksreliable;
105 };
106 
107 /*
108  * The "FTS_NOSTAT" option can avoid a lot of calls to stat(2) if it
109  * knows that a directory could not possibly have subdirectories.  This
110  * is decided by looking at the link count: a subdirectory would
111  * increment its parent's link count by virtue of its own ".." entry.
112  * This assumption only holds for UFS-like filesystems that implement
113  * links and directories this way, so we must punt for others.
114  */
115 static const char *ufslike_filesystems[] = {
116 	"ufs",
117 	"zfs",
118 	"nfs",
119 	"ext2fs",
120 	0
121 };
122 
123 /*
124  * POSIX provides nlink_t but unfortunately not NLINK_MAX.
125  */
126 #define NLINK_MAX \
127 	_Generic((nlink_t)0,						\
128 		int16_t: INT16_MAX,					\
129 		uint16_t: UINT16_MAX,					\
130 		int32_t: INT32_MAX,					\
131 		uint32_t: UINT32_MAX,					\
132 		int64_t: INT64_MAX,					\
133 		uint64_t: UINT64_MAX,					\
134 		default: 0)
135 
136 static FTS15 *
__fts_open(FTS15 * sp,char * const * argv)137 __fts_open(FTS15 *sp, char * const *argv)
138 {
139 	FTSENT15 *p, *root;
140 	FTSENT15 *parent, *tmp;
141 	size_t len, nitems;
142 
143 	/* Logical walks turn on NOCHDIR; symbolic links are too hard. */
144 	if (ISSET(FTS_LOGICAL))
145 		SET(FTS_NOCHDIR);
146 
147 	/* NOSTAT_TYPE implies NOSTAT */
148 	if (ISSET(FTS_NOSTAT_TYPE))
149 		SET(FTS_NOSTAT);
150 
151 	/*
152 	 * Start out with 1K of path space, and enough, in any case,
153 	 * to hold the user's paths.
154 	 */
155 	if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN)))
156 		goto mem1;
157 
158 	/* Allocate/initialize root's parent. */
159 	if ((parent = fts_alloc(sp, "", 0)) == NULL)
160 		goto mem2;
161 	parent->fts_level = FTS_ROOTPARENTLEVEL;
162 
163 	/* Shush, GCC. */
164 	tmp = NULL;
165 
166 	/* Allocate/initialize root(s). */
167 	for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
168 		len = strlen(*argv);
169 
170 		p = fts_alloc(sp, *argv, len);
171 		p->fts_level = FTS_ROOTLEVEL;
172 		p->fts_parent = parent;
173 		p->fts_accpath = p->fts_name;
174 		p->fts_info = fts_stat(sp, p,
175 		    ISSET(FTS_COMFOLLOWDIR) ? -1 : ISSET(FTS_COMFOLLOW),
176 		    -1);
177 
178 		/* Command-line "." and ".." are real directories. */
179 		if (p->fts_info == FTS_DOT)
180 			p->fts_info = FTS_D;
181 
182 		/*
183 		 * If comparison routine supplied, traverse in sorted
184 		 * order; otherwise traverse in the order specified.
185 		 */
186 		if (sp->fts_compar) {
187 			p->fts_link = root;
188 			root = p;
189 		} else {
190 			p->fts_link = NULL;
191 			if (root == NULL)
192 				tmp = root = p;
193 			else {
194 				tmp->fts_link = p;
195 				tmp = p;
196 			}
197 		}
198 	}
199 	if (sp->fts_compar && nitems > 1)
200 		root = fts_sort(sp, root, nitems);
201 
202 	/*
203 	 * Allocate a dummy pointer and make freebsd15_fts_read think that we've just
204 	 * finished the node before the root(s); set p->fts_info to FTS_INIT
205 	 * so that everything about the "current" node is ignored.
206 	 */
207 	if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
208 		goto mem3;
209 	sp->fts_cur->fts_link = root;
210 	sp->fts_cur->fts_info = FTS_INIT;
211 
212 	/*
213 	 * If using chdir(2), grab a file descriptor pointing to dot to ensure
214 	 * that we can get back here; this could be avoided for some paths,
215 	 * but almost certainly not worth the effort.  Slashes, symbolic links,
216 	 * and ".." are all fairly nasty problems.  Note, if we can't get the
217 	 * descriptor we run anyway, just more slowly.
218 	 */
219 	if (!ISSET(FTS_NOCHDIR) &&
220 	    (sp->fts_rfd = _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0)
221 		SET(FTS_NOCHDIR);
222 
223 	return (sp);
224 
225 mem3:	fts_lfree(root);
226 	free(parent);
227 mem2:	free(sp->fts_path);
228 mem1:	free(sp);
229 	return (NULL);
230 }
231 
232 FTS15 *
freebsd15_fts_open(char * const * argv,int options,int (* compar)(const FTSENT15 * const *,const FTSENT15 * const *))233 freebsd15_fts_open(char * const *argv, int options,
234     int (*compar)(const FTSENT15 * const *, const FTSENT15 * const *))
235 {
236 	struct _fts_private *priv;
237 	FTS15 *sp;
238 
239 	/* Options check. */
240 	if (options & ~FTS_OPTIONMASK) {
241 		errno = EINVAL;
242 		return (NULL);
243 	}
244 
245 	/* freebsd15_fts_open() requires at least one path */
246 	if (*argv == NULL) {
247 		errno = EINVAL;
248 		return (NULL);
249 	}
250 
251 	/* Allocate/initialize the stream. */
252 	if ((priv = calloc(1, sizeof(*priv))) == NULL)
253 		return (NULL);
254 	sp = &priv->ftsp_fts;
255 	sp->fts_compar = (int (*)(const FTSENT15 * const *,
256             const FTSENT15 * const *))compar;
257         sp->fts_options = options;
258         return ((FTS15 *)__fts_open(sp, argv));
259 }
260 
261 #ifdef __BLOCKS__
262 FTS15 *
263 freebsd15_fts_open_b(char * const *argv, int options,
264     int (^compar)(const FTSENT15 * const *, const FTSENT15 * const *))
265 #else
266 FTS15 *
267 freebsd15_fts_open_b(char * const *argv, int options, fts_block compar)
268 #endif /* __BLOCKS__ */
269 {
270 	struct _fts_private *priv;
271 	FTS15 *sp;
272 
273 	/* No blocks, no problems. */
274 	if (compar == NULL)
275 		return (freebsd15_fts_open(argv, options, NULL));
276 
277 	/* Avoid segfault if blocks runtime is missing. */
278 	if (_Block_copy == NULL) {
279 		errno = ENOSYS;
280 		return (NULL);
281 	}
282 
283 	/* Options check. */
284 	if (options & ~FTS_OPTIONMASK) {
285 		errno = EINVAL;
286 		return (NULL);
287 	}
288 
289 	/* freebsd15_fts_open() requires at least one path */
290 	if (*argv == NULL) {
291 		errno = EINVAL;
292 		return (NULL);
293 	}
294 
295 	/* Allocate/initialize the stream. */
296 	if ((priv = calloc(1, sizeof(*priv))) == NULL)
297 		return (NULL);
298 	sp = &priv->ftsp_fts;
299 #ifdef __BLOCKS__
300 	compar = Block_copy(compar);
301 #else
302 	if (compar->isa != &_NSConcreteGlobalBlock)
303 		compar = _Block_copy(compar);
304 #endif /* __BLOCKS__ */
305 	if (compar == NULL) {
306 		free(priv);
307 		return (NULL);
308 	}
309 	sp->fts_compar_b = compar;
310 	sp->fts_options = options | FTS_COMPAR_B;
311 
312 	if ((sp = __fts_open(sp, argv)) == NULL) {
313 #ifdef __BLOCKS__
314 		Block_release(compar);
315 #else
316 		if (compar->isa != &_NSConcreteGlobalBlock)
317 			_Block_release(compar);
318 #endif /* __BLOCKS__ */
319 	}
320 	return (sp);
321 }
322 
323 static void
fts_load(FTS15 * sp,FTSENT15 * p)324 fts_load(FTS15 *sp, FTSENT15 *p)
325 {
326 	size_t len;
327 	char *cp;
328 
329 	/*
330 	 * Load the stream structure for the next traversal.  Since we don't
331 	 * actually enter the directory until after the preorder visit, set
332 	 * the fts_accpath field specially so the chdir gets done to the right
333 	 * place and the user can access the first node.  From freebsd15_fts_open it's
334 	 * known that the path will fit.
335 	 */
336 	len = p->fts_pathlen = p->fts_namelen;
337 	memmove(sp->fts_path, p->fts_name, len + 1);
338 	if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
339 		len = strlen(++cp);
340 		memmove(p->fts_name, cp, len + 1);
341 		p->fts_namelen = len;
342 	}
343 	p->fts_accpath = p->fts_path = sp->fts_path;
344 	sp->fts_dev = p->fts_dev;
345 }
346 
347 int
freebsd15_fts_close(FTS15 * sp)348 freebsd15_fts_close(FTS15 *sp)
349 {
350 	FTSENT15 *freep, *p;
351 	int saved_errno;
352 
353 	/*
354 	 * This still works if we haven't read anything -- the dummy structure
355 	 * points to the root list, so we step through to the end of the root
356 	 * list which has a valid parent pointer.
357 	 */
358 	if (sp->fts_cur) {
359 		for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
360 			freep = p;
361 			p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
362 			free(freep);
363 		}
364 		free(p);
365 	}
366 
367 	/* Free up child linked list, sort array, path buffer. */
368 	if (sp->fts_child)
369 		fts_lfree(sp->fts_child);
370 	if (sp->fts_array)
371 		free(sp->fts_array);
372 	free(sp->fts_path);
373 
374 	/* Free up any block pointer. */
375 	if (ISSET(FTS_COMPAR_B) && sp->fts_compar_b != NULL) {
376 #ifdef __BLOCKS__
377 		Block_release(sp->fts_compar_b);
378 #else
379 		if (((fts_block)(sp->fts_compar_b))->isa !=
380 		    &_NSConcreteGlobalBlock)
381 			_Block_release(sp->fts_compar_b);
382 #endif /* __BLOCKS__ */
383 	}
384 
385 	/* Return to original directory, save errno if necessary. */
386 	if (!ISSET(FTS_NOCHDIR)) {
387 		saved_errno = fchdir(sp->fts_rfd) ? errno : 0;
388 		(void)_close(sp->fts_rfd);
389 
390 		/* Set errno and return. */
391 		if (saved_errno != 0) {
392 			/* Free up the stream pointer. */
393 			free(sp);
394 			errno = saved_errno;
395 			return (-1);
396 		}
397 	}
398 
399 	/* Free up the stream pointer. */
400 	free(sp);
401 	return (0);
402 }
403 
404 /*
405  * Special case of "/" at the end of the path so that slashes aren't
406  * appended which would cause paths to be written as "....//foo".
407  */
408 #define	NAPPEND(p)							\
409 	(p->fts_path[p->fts_pathlen - 1] == '/'				\
410 	    ? p->fts_pathlen - 1 : p->fts_pathlen)
411 
412 FTSENT15 *
freebsd15_fts_read(FTS15 * sp)413 freebsd15_fts_read(FTS15 *sp)
414 {
415 	FTSENT15 *p, *tmp;
416 	int instr;
417 	char *t;
418 	int saved_errno;
419 
420 	/* If finished or unrecoverable error, return NULL. */
421 	if (sp->fts_cur == NULL || ISSET(FTS_STOP))
422 		return (NULL);
423 
424 	/* Set current node pointer. */
425 	p = sp->fts_cur;
426 
427 	/* Save and zero out user instructions. */
428 	instr = p->fts_instr;
429 	p->fts_instr = FTS_NOINSTR;
430 
431 	/* Any type of file may be re-visited; re-stat and re-turn. */
432 	if (instr == FTS_AGAIN) {
433 		p->fts_info = fts_stat(sp, p, 0, -1);
434 		return (p);
435 	}
436 
437 	/*
438 	 * Following a symlink -- SLNONE test allows application to see
439 	 * SLNONE and recover.  If indirecting through a symlink, have
440 	 * keep a pointer to current location.  If unable to get that
441 	 * pointer, follow fails.
442 	 */
443 	if (instr == FTS_FOLLOW &&
444 	    (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
445 		p->fts_info = fts_stat(sp, p, 1, -1);
446 		if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
447 			if ((p->fts_symfd = _open(".", O_RDONLY | O_CLOEXEC,
448 			    0)) < 0) {
449 				p->fts_errno = errno;
450 				p->fts_info = FTS_ERR;
451 			} else
452 				p->fts_flags |= FTS_SYMFOLLOW;
453 		}
454 		return (p);
455 	}
456 
457 	/* Directory in pre-order. */
458 	if (p->fts_info == FTS_D) {
459 		/* If skipped or crossed mount point, do post-order visit. */
460 		if (instr == FTS_SKIP ||
461 		    (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) {
462 			if (p->fts_flags & FTS_SYMFOLLOW)
463 				(void)_close(p->fts_symfd);
464 			if (sp->fts_child) {
465 				fts_lfree(sp->fts_child);
466 				sp->fts_child = NULL;
467 			}
468 			p->fts_info = FTS_DP;
469 			return (p);
470 		}
471 
472 		/* Rebuild if only read the names and now traversing. */
473 		if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
474 			CLR(FTS_NAMEONLY);
475 			fts_lfree(sp->fts_child);
476 			sp->fts_child = NULL;
477 		}
478 
479 		/*
480 		 * Cd to the subdirectory.
481 		 *
482 		 * If have already read and now fail to chdir, whack the list
483 		 * to make the names come out right, and set the parent errno
484 		 * so the application will eventually get an error condition.
485 		 * Set the FTS_DONTCHDIR flag so that when we logically change
486 		 * directories back to the parent we don't do a chdir.
487 		 *
488 		 * If haven't read do so.  If the read fails, fts_build sets
489 		 * FTS_STOP or the fts_info field of the node.
490 		 */
491 		if (sp->fts_child != NULL) {
492 			if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
493 				p->fts_errno = errno;
494 				p->fts_flags |= FTS_DONTCHDIR;
495 				for (p = sp->fts_child; p != NULL;
496 				    p = p->fts_link)
497 					p->fts_accpath =
498 					    p->fts_parent->fts_accpath;
499 			}
500 		} else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
501 			if (ISSET(FTS_STOP))
502 				return (NULL);
503 			return (p);
504 		}
505 		p = sp->fts_child;
506 		sp->fts_child = NULL;
507 		goto name;
508 	}
509 
510 	/* Move to the next node on this level. */
511 next:	tmp = p;
512 	if ((p = p->fts_link) != NULL) {
513 		/*
514 		 * If reached the top, return to the original directory (or
515 		 * the root of the tree), and load the paths for the next root.
516 		 */
517 		if (p->fts_level == FTS_ROOTLEVEL) {
518 			if (FCHDIR(sp, sp->fts_rfd)) {
519 				SET(FTS_STOP);
520 				return (NULL);
521 			}
522 			free(tmp);
523 			fts_load(sp, p);
524 			return (sp->fts_cur = p);
525 		}
526 
527 		/*
528 		 * User may have called freebsd15_fts_set on the node.  If skipped,
529 		 * ignore.  If followed, get a file descriptor so we can
530 		 * get back if necessary.
531 		 */
532 		if (p->fts_instr == FTS_SKIP) {
533 			free(tmp);
534 			goto next;
535 		}
536 		if (p->fts_instr == FTS_FOLLOW) {
537 			p->fts_info = fts_stat(sp, p, 1, -1);
538 			if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
539 				if ((p->fts_symfd =
540 				    _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0) {
541 					p->fts_errno = errno;
542 					p->fts_info = FTS_ERR;
543 				} else
544 					p->fts_flags |= FTS_SYMFOLLOW;
545 			}
546 			p->fts_instr = FTS_NOINSTR;
547 		}
548 
549 		free(tmp);
550 
551 name:		t = sp->fts_path + NAPPEND(p->fts_parent);
552 		*t++ = '/';
553 		memmove(t, p->fts_name, p->fts_namelen + 1);
554 		return (sp->fts_cur = p);
555 	}
556 
557 	/* Move up to the parent node. */
558 	p = tmp->fts_parent;
559 
560 	if (p->fts_level == FTS_ROOTPARENTLEVEL) {
561 		/*
562 		 * Done; free everything up and set errno to 0 so the user
563 		 * can distinguish between error and EOF.
564 		 */
565 		free(tmp);
566 		free(p);
567 		errno = 0;
568 		return (sp->fts_cur = NULL);
569 	}
570 
571 	/* NUL terminate the pathname. */
572 	sp->fts_path[p->fts_pathlen] = '\0';
573 
574 	/*
575 	 * Return to the parent directory.  If at a root node or came through
576 	 * a symlink, go back through the file descriptor.  Otherwise, cd up
577 	 * one directory.
578 	 */
579 	if (p->fts_level == FTS_ROOTLEVEL) {
580 		if (FCHDIR(sp, sp->fts_rfd)) {
581 			SET(FTS_STOP);
582 			return (NULL);
583 		}
584 	} else if (p->fts_flags & FTS_SYMFOLLOW) {
585 		if (FCHDIR(sp, p->fts_symfd)) {
586 			saved_errno = errno;
587 			(void)_close(p->fts_symfd);
588 			errno = saved_errno;
589 			SET(FTS_STOP);
590 			return (NULL);
591 		}
592 		(void)_close(p->fts_symfd);
593 	} else if (!(p->fts_flags & FTS_DONTCHDIR) &&
594 	    fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
595 		SET(FTS_STOP);
596 		return (NULL);
597 	}
598 	free(tmp);
599 	p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
600 	return (sp->fts_cur = p);
601 }
602 
603 /*
604  * Fts_set takes the stream as an argument although it's not used in this
605  * implementation; it would be necessary if anyone wanted to add global
606  * semantics to fts using freebsd15_fts_set.  An error return is allowed for similar
607  * reasons.
608  */
609 /* ARGSUSED */
610 int
freebsd15_fts_set(FTS15 * sp,FTSENT15 * p,int instr)611 freebsd15_fts_set(FTS15 *sp, FTSENT15 *p, int instr)
612 {
613 	if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
614 	    instr != FTS_NOINSTR && instr != FTS_SKIP) {
615 		errno = EINVAL;
616 		return (1);
617 	}
618 	p->fts_instr = instr;
619 	return (0);
620 }
621 
622 FTSENT15 *
freebsd15_fts_children(FTS15 * sp,int instr)623 freebsd15_fts_children(FTS15 *sp, int instr)
624 {
625 	FTSENT15 *p;
626 	int fd, rc, serrno;
627 
628 	if (instr != 0 && instr != FTS_NAMEONLY) {
629 		errno = EINVAL;
630 		return (NULL);
631 	}
632 
633 	/* Set current node pointer. */
634 	p = sp->fts_cur;
635 
636 	/*
637 	 * Errno set to 0 so user can distinguish empty directory from
638 	 * an error.
639 	 */
640 	errno = 0;
641 
642 	/* Fatal errors stop here. */
643 	if (ISSET(FTS_STOP))
644 		return (NULL);
645 
646 	/* Return logical hierarchy of user's arguments. */
647 	if (p->fts_info == FTS_INIT)
648 		return (p->fts_link);
649 
650 	/*
651 	 * If not a directory being visited in pre-order, stop here.  Could
652 	 * allow FTS_DNR, assuming the user has fixed the problem, but the
653 	 * same effect is available with FTS_AGAIN.
654 	 */
655 	if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
656 		return (NULL);
657 
658 	/* Free up any previous child list. */
659 	if (sp->fts_child != NULL)
660 		fts_lfree(sp->fts_child);
661 
662 	if (instr == FTS_NAMEONLY) {
663 		SET(FTS_NAMEONLY);
664 		instr = BNAMES;
665 	} else
666 		instr = BCHILD;
667 
668 	/*
669 	 * If using chdir on a relative path and called BEFORE freebsd15_fts_read does
670 	 * its chdir to the root of a traversal, we can lose -- we need to
671 	 * chdir into the subdirectory, and we don't know where the current
672 	 * directory is, so we can't get back so that the upcoming chdir by
673 	 * freebsd15_fts_read will work.
674 	 */
675 	if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
676 	    ISSET(FTS_NOCHDIR))
677 		return (sp->fts_child = fts_build(sp, instr));
678 
679 	if ((fd = _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0)
680 		return (NULL);
681 	sp->fts_child = fts_build(sp, instr);
682 	serrno = (sp->fts_child == NULL) ? errno : 0;
683 	rc = fchdir(fd);
684 	if (rc < 0 && serrno == 0)
685 		serrno = errno;
686 	(void)_close(fd);
687 	errno = serrno;
688 	if (rc < 0)
689 		return (NULL);
690 	return (sp->fts_child);
691 }
692 
693 #ifndef freebsd15_fts_get_clientptr
694 #error "freebsd15_fts_get_clientptr not defined"
695 #endif
696 
697 void *
698 (freebsd15_fts_get_clientptr)(FTS15 *sp)
699 {
700 	return (freebsd15_fts_get_clientptr(sp));
701 }
702 
703 #ifndef freebsd15_fts_get_stream
704 #error "freebsd15_fts_get_stream not defined"
705 #endif
706 
707 FTS15 *
708 (freebsd15_fts_get_stream)(FTSENT15 *p)
709 {
710 	return (freebsd15_fts_get_stream(p));
711 }
712 
713 void
freebsd15_fts_set_clientptr(FTS15 * sp,void * clientptr)714 freebsd15_fts_set_clientptr(FTS15 *sp, void *clientptr)
715 {
716 	sp->fts_clientptr = clientptr;
717 }
718 
719 static struct dirent *
fts_safe_readdir(DIR * dirp,int * readdir_errno)720 fts_safe_readdir(DIR *dirp, int *readdir_errno)
721 {
722 	struct dirent *ret;
723 
724 	errno = 0;
725 	if (!dirp)
726 		return (NULL);
727 	ret = readdir(dirp);
728 	*readdir_errno = errno;
729 	return (ret);
730 }
731 
732 /*
733  * This is the tricky part -- do not casually change *anything* in here.  The
734  * idea is to build the linked list of entries that are used by freebsd15_fts_children
735  * and freebsd15_fts_read.  There are lots of special cases.
736  *
737  * The real slowdown in walking the tree is the stat calls.  If FTS_NOSTAT is
738  * set and it's a physical walk (so that symbolic links can't be directories),
739  * we can do things quickly.  First, if it's a 4.4BSD file system, the type
740  * of the file is in the directory entry.  Otherwise, we assume that the number
741  * of subdirectories in a node is equal to the number of links to the parent.
742  * The former skips all stat calls.  The latter skips stat calls in any leaf
743  * directories and for any files after the subdirectories in the directory have
744  * been found, cutting the stat calls by about 2/3.
745  */
746 static FTSENT15 *
fts_build(FTS15 * sp,int type)747 fts_build(FTS15 *sp, int type)
748 {
749 	struct dirent *dp;
750 	FTSENT15 *p, *head;
751 	FTSENT15 *cur, *tail;
752 	DIR *dirp;
753 	void *oldaddr;
754 	char *cp;
755 	int cderrno, descend, oflag, saved_errno, nostat, doadjust,
756 	    readdir_errno;
757 	long level;
758 	int64_t nlinks;	/* has to be signed because -1 is a magic value */
759 	size_t dnamlen, len, maxlen, nitems;
760 
761 	/* Set current node pointer. */
762 	cur = sp->fts_cur;
763 
764 	/*
765 	 * Open the directory for reading.  If this fails, we're done.
766 	 * If being called from freebsd15_fts_read, set the fts_info field.
767 	 */
768 	if (ISSET(FTS_WHITEOUT))
769 		oflag = DTF_NODUP;
770 	else
771 		oflag = DTF_HIDEW | DTF_NODUP;
772 	if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
773 		if (type == BREAD) {
774 			cur->fts_info = FTS_DNR;
775 			cur->fts_errno = errno;
776 		}
777 		return (NULL);
778 	}
779 
780 	/*
781 	 * In the FTS_PHYSICAL | FTS_NOSTAT case, we want to avoid calling
782 	 * fstat() unnecessarily, but we still need to call it for
783 	 * subdirectories.  The current directory's link count provides an
784 	 * upper bound on the number of subdirectories we may encounter
785 	 * (including . and .. in the FTS_SEEDOT case).  We initialize
786 	 * nlinks to the current directory's link count, then decrement it
787 	 * every time we encounter a directory, so when we hit zero we can
788 	 * save some time by not calling fstat() on subsequent entries.
789 	 *
790 	 * If FTS_NOSTAT is not set, or the link count is less than two
791 	 * (which should not be possible) or equal to NLINK_MAX (which
792 	 * suggests that the actual value could be higher), or the current
793 	 * filesystem is not known to provide reliable link counts, we
794 	 * initialize nlinks to -1 and fstat() everything.
795 	 *
796 	 * In the rare case where we don't need to stat anything, even
797 	 * subdirectories, we initialize nlinks to 0 regardless of the
798 	 * actual link count.
799 	 *
800 	 * Note that we ignore the FTS_NOSTAT flag in the FTS_LOGICAL
801 	 * case, although we could choose to only stat symbolic links.
802 	 * Implementing this is left as an exercise for the reader.
803 	 */
804 	if (type == BNAMES) {
805 		nlinks = 0;
806 		/* Be quiet about nostat, GCC. */
807 		nostat = 0;
808 	} else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
809 		if (cur->fts_nlink >= 2 && cur->fts_nlink < NLINK_MAX &&
810 		    cur->fts_nlink <= INT64_MAX && fts_ufslinks(sp, cur))
811 			nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2);
812 		else
813 			nlinks = -1;
814 		nostat = 1;
815 	} else {
816 		nlinks = -1;
817 		nostat = 0;
818 	}
819 
820 #ifdef notdef
821 	(void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink);
822 	(void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n",
823 	    ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT));
824 #endif
825 	/*
826 	 * If we're going to need to stat anything or we want to descend
827 	 * and stay in the directory, chdir.  If this fails we keep going,
828 	 * but set a flag so we don't chdir after the post-order visit.
829 	 * We won't be able to stat anything, but we can still return the
830 	 * names themselves.  Note, that since freebsd15_fts_read won't be able to
831 	 * chdir into the directory, it will have to return different path
832 	 * names than before, i.e. "a/b" instead of "b".  Since the node
833 	 * has already been visited in pre-order, have to wait until the
834 	 * post-order visit to return the error.  There is a special case
835 	 * here, if there was nothing to stat then it's not an error to
836 	 * not be able to stat.  This is all fairly nasty.  If a program
837 	 * needed sorted entries or stat information, they had better be
838 	 * checking FTS_NS on the returned nodes.
839 	 */
840 	cderrno = 0;
841 	if (nlinks || type == BREAD) {
842 		if (fts_safe_changedir(sp, cur, _dirfd(dirp), NULL)) {
843 			if (nlinks && type == BREAD)
844 				cur->fts_errno = errno;
845 			cur->fts_flags |= FTS_DONTCHDIR;
846 			descend = 0;
847 			cderrno = errno;
848 		} else
849 			descend = 1;
850 	} else
851 		descend = 0;
852 
853 	/*
854 	 * Figure out the max file name length that can be stored in the
855 	 * current path -- the inner loop allocates more path as necessary.
856 	 * We really wouldn't have to do the maxlen calculations here, we
857 	 * could do them in freebsd15_fts_read before returning the path, but it's a
858 	 * lot easier here since the length is part of the dirent structure.
859 	 *
860 	 * If not changing directories set a pointer so that can just append
861 	 * each new name into the path.
862 	 */
863 	len = NAPPEND(cur);
864 	if (ISSET(FTS_NOCHDIR)) {
865 		cp = sp->fts_path + len;
866 		*cp++ = '/';
867 	} else {
868 		/* GCC, you're too verbose. */
869 		cp = NULL;
870 	}
871 	len++;
872 	maxlen = sp->fts_pathlen - len;
873 
874 	level = cur->fts_level + 1;
875 
876 	/* Read the directory, attaching each entry to the `link' pointer. */
877 	doadjust = 0;
878 	readdir_errno = 0;
879 	for (head = tail = NULL, nitems = 0;
880 	    (dp = fts_safe_readdir(dirp, &readdir_errno));) {
881 		dnamlen = dp->d_namlen;
882 		if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
883 			continue;
884 
885 		if ((p = fts_alloc(sp, dp->d_name, dnamlen)) == NULL)
886 			goto mem1;
887 		if (dnamlen >= maxlen) {	/* include space for NUL */
888 			oldaddr = sp->fts_path;
889 			if (fts_palloc(sp, dnamlen + len + 1)) {
890 				/*
891 				 * No more memory for path or structures.  Save
892 				 * errno, free up the current structure and the
893 				 * structures already allocated.
894 				 */
895 mem1:				saved_errno = errno;
896 				if (p)
897 					free(p);
898 				fts_lfree(head);
899 				(void)closedir(dirp);
900 				cur->fts_info = FTS_ERR;
901 				SET(FTS_STOP);
902 				errno = saved_errno;
903 				return (NULL);
904 			}
905 			/* Did realloc() change the pointer? */
906 			if (oldaddr != sp->fts_path) {
907 				doadjust = 1;
908 				if (ISSET(FTS_NOCHDIR))
909 					cp = sp->fts_path + len;
910 			}
911 			maxlen = sp->fts_pathlen - len;
912 		}
913 
914 		p->fts_level = level;
915 		p->fts_parent = sp->fts_cur;
916 		p->fts_pathlen = len + dnamlen;
917 
918 		if (dp->d_type == DT_WHT)
919 			p->fts_flags |= FTS_ISW;
920 
921 		if (cderrno) {
922 			if (nlinks) {
923 				p->fts_info = FTS_NS;
924 				p->fts_errno = cderrno;
925 			} else
926 				p->fts_info = FTS_NSOK;
927 			p->fts_accpath = cur->fts_accpath;
928 		} else if (nlinks == 0 || (nostat &&
929 		    dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN)) {
930 			p->fts_accpath =
931 			    ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name;
932 			p->fts_info = FTS_NSOK;
933 		} else {
934 			/* Build a file name for fts_stat to stat. */
935 			if (ISSET(FTS_NOCHDIR)) {
936 				p->fts_accpath = p->fts_path;
937 				memmove(cp, p->fts_name, p->fts_namelen + 1);
938 				p->fts_info = fts_stat(sp, p, 0, _dirfd(dirp));
939 			} else {
940 				p->fts_accpath = p->fts_name;
941 				p->fts_info = fts_stat(sp, p, 0, -1);
942 			}
943 
944 			/* Decrement link count if applicable. */
945 			if (nlinks > 0 && (p->fts_info == FTS_D ||
946 			    p->fts_info == FTS_DC || p->fts_info == FTS_DOT))
947 				--nlinks;
948 		}
949 		if (p->fts_info == FTS_NSOK && ISSET(FTS_NOSTAT_TYPE)) {
950 			switch (dp->d_type) {
951 			case DT_FIFO:
952 			case DT_CHR:
953 			case DT_BLK:
954 			case DT_SOCK:
955 				p->fts_info = FTS_DEFAULT;
956 				break;
957 			case DT_REG:
958 				p->fts_info = FTS_F;
959 				break;
960 			case DT_LNK:
961 				p->fts_info = FTS_SL;
962 				break;
963 			case DT_WHT:
964 				p->fts_info = FTS_W;
965 				break;
966 			}
967 		}
968 
969 		/* We walk in directory order so "ls -f" doesn't get upset. */
970 		p->fts_link = NULL;
971 		if (head == NULL)
972 			head = tail = p;
973 		else {
974 			tail->fts_link = p;
975 			tail = p;
976 		}
977 		++nitems;
978 	}
979 
980 	if (readdir_errno) {
981 		cur->fts_errno = readdir_errno;
982 		/*
983 		 * If we've not read any items yet, treat
984 		 * the error as if we can't access the dir.
985 		 */
986 		cur->fts_info = nitems ? FTS_ERR : FTS_DNR;
987 	}
988 
989 	if (dirp)
990 		(void)closedir(dirp);
991 
992 	/*
993 	 * If realloc() changed the address of the path, adjust the
994 	 * addresses for the rest of the tree and the dir list.
995 	 */
996 	if (doadjust)
997 		fts_padjust(sp, head);
998 
999 	/*
1000 	 * If not changing directories, reset the path back to original
1001 	 * state.
1002 	 */
1003 	if (ISSET(FTS_NOCHDIR))
1004 		sp->fts_path[cur->fts_pathlen] = '\0';
1005 
1006 	/*
1007 	 * If descended after called from freebsd15_fts_children or after called from
1008 	 * freebsd15_fts_read and nothing found, get back.  At the root level we use
1009 	 * the saved fd; if one of freebsd15_fts_open()'s arguments is a relative path
1010 	 * to an empty directory, we wind up here with no other way back.  If
1011 	 * can't get back, we're done.
1012 	 */
1013 	if (descend && (type == BCHILD || !nitems) &&
1014 	    (cur->fts_level == FTS_ROOTLEVEL ?
1015 	    FCHDIR(sp, sp->fts_rfd) :
1016 	    fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1017 		fts_lfree(head);
1018 		cur->fts_info = FTS_ERR;
1019 		SET(FTS_STOP);
1020 		return (NULL);
1021 	}
1022 
1023 	/* If didn't find anything, return NULL. */
1024 	if (!nitems) {
1025 		if (type == BREAD &&
1026 		    cur->fts_info != FTS_DNR && cur->fts_info != FTS_ERR)
1027 			cur->fts_info = FTS_DP;
1028 		return (NULL);
1029 	}
1030 
1031 	/* Sort the entries. */
1032 	if (sp->fts_compar && nitems > 1)
1033 		head = fts_sort(sp, head, nitems);
1034 	return (head);
1035 }
1036 
1037 static int
fts_stat(FTS15 * sp,FTSENT15 * p,int follow,int dfd)1038 fts_stat(FTS15 *sp, FTSENT15 *p, int follow, int dfd)
1039 {
1040 	FTSENT15 *t;
1041 	dev_t dev;
1042 	ino_t ino;
1043 	struct stat *sbp, sb;
1044 	int ret, saved_errno;
1045 	const char *path;
1046 
1047 	if (dfd == -1) {
1048 		path = p->fts_accpath;
1049 		dfd = AT_FDCWD;
1050 	} else {
1051 		path = p->fts_name;
1052 	}
1053 
1054 	/* If user needs stat info, stat buffer already allocated. */
1055 	sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp;
1056 
1057 	/* Check for whiteout. */
1058 	if (p->fts_flags & FTS_ISW) {
1059 		if (sbp != &sb) {
1060 			memset(sbp, '\0', sizeof(*sbp));
1061 			sbp->st_mode = S_IFWHT;
1062 		}
1063 		return (FTS_W);
1064 	}
1065 
1066 	/*
1067 	 * If doing a logical walk, or caller requested FTS_COMFOLLOW, do
1068 	 * a full stat(2).  If that fails, do an lstat(2) to check for a
1069 	 * non-existent symlink.  If that fails, set the errno from the
1070 	 * stat(2) call.
1071 	 *
1072 	 * As a special case, if stat(2) succeeded but the target is not a
1073 	 * directory and follow is negative (indicating FTS_COMFOLLOWDIR
1074 	 * rather than FTS_COMFOLLOW), we also revert to lstat(2).
1075 	 */
1076 	if (ISSET(FTS_LOGICAL) || follow) {
1077 		if ((ret = fstatat(dfd, path, sbp, 0)) != 0 ||
1078 		    (follow < 0 && !S_ISDIR(sbp->st_mode))) {
1079 			saved_errno = errno;
1080 			if (fstatat(dfd, path, sbp, AT_SYMLINK_NOFOLLOW)) {
1081 				p->fts_errno = saved_errno;
1082 				goto err;
1083 			}
1084 			errno = 0;
1085 			if (ret != 0 && S_ISLNK(sbp->st_mode))
1086 				return (FTS_SLNONE);
1087 		}
1088 	} else if (fstatat(dfd, path, sbp, AT_SYMLINK_NOFOLLOW)) {
1089 		p->fts_errno = errno;
1090 err:		memset(sbp, 0, sizeof(struct stat));
1091 		return (FTS_NS);
1092 	}
1093 
1094 	if (S_ISDIR(sbp->st_mode)) {
1095 		/*
1096 		 * Set the device/inode.  Used to find cycles and check for
1097 		 * crossing mount points.  Also remember the link count, used
1098 		 * in fts_build to limit the number of stat calls.  It is
1099 		 * understood that these fields are only referenced if fts_info
1100 		 * is set to FTS_D.
1101 		 */
1102 		dev = p->fts_dev = sbp->st_dev;
1103 		ino = p->fts_ino = sbp->st_ino;
1104 		p->fts_nlink = sbp->st_nlink;
1105 
1106 		if (ISDOT(p->fts_name))
1107 			return (FTS_DOT);
1108 
1109 		/*
1110 		 * Cycle detection is done by brute force when the directory
1111 		 * is first encountered.  If the tree gets deep enough or the
1112 		 * number of symbolic links to directories is high enough,
1113 		 * something faster might be worthwhile.
1114 		 */
1115 		for (t = p->fts_parent;
1116 		    t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1117 			if (ino == t->fts_ino && dev == t->fts_dev) {
1118 				p->fts_cycle = t;
1119 				return (FTS_DC);
1120 			}
1121 		return (FTS_D);
1122 	}
1123 	if (S_ISLNK(sbp->st_mode))
1124 		return (FTS_SL);
1125 	if (S_ISREG(sbp->st_mode))
1126 		return (FTS_F);
1127 	return (FTS_DEFAULT);
1128 }
1129 
1130 static FTSENT15 *
fts_sort(FTS15 * sp,FTSENT15 * head,size_t nitems)1131 fts_sort(FTS15 *sp, FTSENT15 *head, size_t nitems)
1132 {
1133 	FTSENT15 **ap, *p;
1134 
1135 	/*
1136 	 * Construct an array of pointers to the structures and call qsort(3).
1137 	 * Reassemble the array in the order returned by qsort.  If unable to
1138 	 * sort for memory reasons, return the directory entries in their
1139 	 * current order.  Allocate enough space for the current needs plus
1140 	 * 40 so don't realloc one entry at a time.
1141 	 */
1142 	if (nitems > sp->fts_nitems) {
1143 		sp->fts_nitems = nitems + 40;
1144 		if ((sp->fts_array = reallocf(sp->fts_array,
1145 		    sp->fts_nitems * sizeof(FTSENT15 *))) == NULL) {
1146 			sp->fts_nitems = 0;
1147 			return (head);
1148 		}
1149 	}
1150 	for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1151 		*ap++ = p;
1152 	if (ISSET(FTS_COMPAR_B)) {
1153 #ifdef __BLOCKS__
1154 		qsort_b(sp->fts_array, nitems, sizeof(FTSENT15 *),
1155 		    (int (^)(const void *, const void *))sp->fts_compar_b);
1156 #else
1157 		qsort_b(sp->fts_array, nitems, sizeof(FTSENT15 *),
1158 		    sp->fts_compar_b);
1159 #endif /* __BLOCKS__ */
1160 	} else {
1161 		qsort(sp->fts_array, nitems, sizeof(FTSENT15 *),
1162 		    (int (*)(const void *, const void *))sp->fts_compar);
1163 	}
1164 	for (head = *(ap = sp->fts_array); --nitems; ++ap)
1165 		ap[0]->fts_link = ap[1];
1166 	ap[0]->fts_link = NULL;
1167 	return (head);
1168 }
1169 
1170 static FTSENT15 *
fts_alloc(FTS15 * sp,char * name,size_t namelen)1171 fts_alloc(FTS15 *sp, char *name, size_t namelen)
1172 {
1173 	FTSENT15 *p;
1174 	size_t len;
1175 
1176 	/*
1177 	 * The file name is a variable length array and no stat structure is
1178 	 * necessary if the user has set the nostat bit.  Allocate the FTSENT15
1179 	 * structure, the file name and the stat structure in one chunk, but
1180 	 * be careful that the stat structure is reasonably aligned.
1181 	 */
1182 	len = sizeof(FTSENT15) + namelen + 1;
1183 	if (!ISSET(FTS_NOSTAT)) {
1184 		len = roundup(len, alignof(struct stat));
1185 		p = calloc(1, len + sizeof(struct stat));
1186 	} else {
1187 		p = calloc(1, len);
1188 	}
1189 	if (p == NULL)
1190 		return (NULL);
1191 
1192 	p->fts_symfd = -1;
1193 	p->fts_path = sp->fts_path;
1194 	p->fts_name = (char *)(p + 1);
1195 	p->fts_namelen = namelen;
1196 	p->fts_instr = FTS_NOINSTR;
1197 	if (!ISSET(FTS_NOSTAT))
1198 		p->fts_statp = (struct stat *)((char *)p + len);
1199 	p->fts_fts = sp;
1200 	memcpy(p->fts_name, name, namelen);
1201 
1202 	return (p);
1203 }
1204 
1205 static void
fts_lfree(FTSENT15 * head)1206 fts_lfree(FTSENT15 *head)
1207 {
1208 	FTSENT15 *p;
1209 
1210 	/* Free a linked list of structures. */
1211 	while ((p = head)) {
1212 		head = head->fts_link;
1213 		free(p);
1214 	}
1215 }
1216 
1217 /*
1218  * Allow essentially unlimited paths; find, rm, ls should all work on any tree.
1219  * Most systems will allow creation of paths much longer than MAXPATHLEN, even
1220  * though the kernel won't resolve them.  Add the size (not just what's needed)
1221  * plus 256 bytes so don't realloc the path 2 bytes at a time.
1222  */
1223 static int
fts_palloc(FTS15 * sp,size_t more)1224 fts_palloc(FTS15 *sp, size_t more)
1225 {
1226 
1227 	sp->fts_pathlen += more + 256;
1228 	sp->fts_path = reallocf(sp->fts_path, sp->fts_pathlen);
1229 	return (sp->fts_path == NULL);
1230 }
1231 
1232 /*
1233  * When the path is realloc'd, have to fix all of the pointers in structures
1234  * already returned.
1235  */
1236 static void
fts_padjust(FTS15 * sp,FTSENT15 * head)1237 fts_padjust(FTS15 *sp, FTSENT15 *head)
1238 {
1239 	FTSENT15 *p;
1240 	char *addr = sp->fts_path;
1241 
1242 #define	ADJUST(p) do {							\
1243 	if ((p)->fts_accpath != (p)->fts_name) {			\
1244 		(p)->fts_accpath =					\
1245 		    (char *)addr + ((p)->fts_accpath - (p)->fts_path);	\
1246 	}								\
1247 	(p)->fts_path = addr;						\
1248 } while (0)
1249 	/* Adjust the current set of children. */
1250 	for (p = sp->fts_child; p; p = p->fts_link)
1251 		ADJUST(p);
1252 
1253 	/* Adjust the rest of the tree, including the current level. */
1254 	for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1255 		ADJUST(p);
1256 		p = p->fts_link ? p->fts_link : p->fts_parent;
1257 	}
1258 }
1259 
1260 static size_t
fts_maxarglen(char * const * argv)1261 fts_maxarglen(char * const *argv)
1262 {
1263 	size_t len, max;
1264 
1265 	for (max = 0; *argv; ++argv)
1266 		if ((len = strlen(*argv)) > max)
1267 			max = len;
1268 	return (max + 1);
1269 }
1270 
1271 /*
1272  * Change to dir specified by fd or p->fts_accpath without getting
1273  * tricked by someone changing the world out from underneath us.
1274  * Assumes p->fts_dev and p->fts_ino are filled in.
1275  */
1276 static int
fts_safe_changedir(FTS15 * sp,FTSENT15 * p,int fd,char * path)1277 fts_safe_changedir(FTS15 *sp, FTSENT15 *p, int fd, char *path)
1278 {
1279 	int ret, oerrno, newfd;
1280 	struct stat sb;
1281 	struct statfs sf;
1282 
1283 	newfd = fd;
1284 	if (ISSET(FTS_NOCHDIR))
1285 		return (0);
1286 	if (fd < 0 && (newfd = _open(path, O_RDONLY | O_DIRECTORY |
1287 	    O_CLOEXEC, 0)) < 0)
1288 		return (-1);
1289 	if (_fstat(newfd, &sb)) {
1290 		ret = -1;
1291 		goto bail;
1292 	}
1293 	if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) {
1294 		if (_fstatfs(newfd, &sf) != 0 ||
1295 		    (sf.f_flags & MNT_AUTOMOUNTED) == 0) {
1296 			errno = ENOENT;		/* disinformation */
1297 			ret = -1;
1298 			goto bail;
1299 		}
1300 		/* autofs might did the mount under us, accept. */
1301 		p->fts_dev = sb.st_dev;
1302 		p->fts_ino = sb.st_ino;
1303 	}
1304 	ret = fchdir(newfd);
1305 bail:
1306 	oerrno = errno;
1307 	if (fd < 0)
1308 		(void)_close(newfd);
1309 	errno = oerrno;
1310 	return (ret);
1311 }
1312 
1313 /*
1314  * Check if the filesystem for "ent" has UFS-style links.
1315  */
1316 static int
fts_ufslinks(FTS15 * sp,const FTSENT15 * ent)1317 fts_ufslinks(FTS15 *sp, const FTSENT15 *ent)
1318 {
1319 	struct _fts_private *priv;
1320 	const char **cpp;
1321 
1322 	priv = (struct _fts_private *)sp;
1323 	/*
1324 	 * If this node's device is different from the previous, grab
1325 	 * the filesystem information, and decide on the reliability
1326 	 * of the link information from this filesystem for stat(2)
1327 	 * avoidance.
1328 	 */
1329 	if (priv->ftsp_dev != ent->fts_dev) {
1330 		if (statfs(ent->fts_path, &priv->ftsp_statfs) != -1) {
1331 			priv->ftsp_dev = ent->fts_dev;
1332 			priv->ftsp_linksreliable = 0;
1333 			for (cpp = ufslike_filesystems; *cpp; cpp++) {
1334 				if (strcmp(priv->ftsp_statfs.f_fstypename,
1335 				    *cpp) == 0) {
1336 					priv->ftsp_linksreliable = 1;
1337 					break;
1338 				}
1339 			}
1340 		} else {
1341 			priv->ftsp_linksreliable = 0;
1342 		}
1343 	}
1344 	return (priv->ftsp_linksreliable);
1345 }
1346 
1347 __sym_compat(fts_open, freebsd15_fts_open, FBSD_1.5);
1348 __sym_compat(fts_close, freebsd15_fts_close, FBSD_1.5);
1349 __sym_compat(fts_read, freebsd15_fts_read, FBSD_1.5);
1350 __sym_compat(fts_set, freebsd15_fts_set, FBSD_1.5);
1351 __sym_compat(fts_children, freebsd15_fts_children, FBSD_1.5);
1352 __sym_compat(fts_get_clientptr, freebsd15_fts_get_clientptr, FBSD_1.5);
1353 __sym_compat(fts_get_stream, freebsd15_fts_get_stream, FBSD_1.5);
1354 __sym_compat(fts_set_clientptr, freebsd15_fts_set_clientptr, FBSD_1.5);
1355 __sym_compat(fts_open_b, freebsd15_fts_open_b, FBSD_1.5);
1356