1 /* Traverse a file hierarchy.
3 Copyright (C) 2004-2009 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 * Copyright (c) 1990, 1993, 1994
20 * The Regents of the University of California. All rights reserved.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the above copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 4. Neither the name of the University nor the names of its contributors
31 * may be used to endorse or promote products derived from this software
32 * without specific prior written permission.
34 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
35 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
36 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
37 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
38 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
39 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
40 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
41 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
42 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
43 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
49 #if defined(LIBC_SCCS) && !defined(lint)
50 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
51 #endif /* LIBC_SCCS and not lint */
55 #if HAVE_SYS_PARAM_H || defined _LIBC
56 # include <sys/param.h>
59 # include <include/sys/stat.h>
61 # include <sys/stat.h>
72 # include "dirent--.h"
73 # include "unistd--.h"
74 /* FIXME - use fcntl(F_DUPFD_CLOEXEC)/openat(O_CLOEXEC) once they are
78 # include "same-inode.h"
82 #ifndef _D_EXACT_NAMLEN
83 # define _D_EXACT_NAMLEN(dirent) strlen ((dirent)->d_name)
86 #if HAVE_STRUCT_DIRENT_D_TYPE
87 /* True if the type of the directory entry D is known. */
88 # define DT_IS_KNOWN(d) ((d)->d_type != DT_UNKNOWN)
89 /* True if the type of the directory entry D must be T. */
90 # define DT_MUST_BE(d, t) ((d)->d_type == (t))
91 # define D_TYPE(d) ((d)->d_type)
93 # define DT_IS_KNOWN(d) false
94 # define DT_MUST_BE(d, t) false
95 # define D_TYPE(d) DT_UNKNOWN
100 /* Any nonzero values will do here, so long as they're distinct.
101 Undef any existing macros out of the way. */
127 NOT_AN_INODE_NUMBER = 0
130 #ifdef D_INO_IN_DIRENT
131 # define D_INO(dp) (dp)->d_ino
133 /* Some systems don't have inodes, so fake them to avoid lots of ifdefs. */
134 # define D_INO(dp) NOT_AN_INODE_NUMBER
137 /* If there are more than this many entries in a directory,
138 and the conditions mentioned below are satisfied, then sort
139 the entries on inode number before any further processing. */
140 #ifndef FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
141 # define FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD 10000
145 _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD = FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
150 FTS_NO_STAT_REQUIRED = 1,
151 FTS_STAT_REQUIRED = 2
156 # define close __close
158 # define closedir __closedir
160 # define fchdir __fchdir
164 # define opendir __opendir
166 # define readdir __readdir
168 # undef internal_function
169 # define internal_function /* empty */
173 # define __set_errno(Val) errno = (Val)
176 #ifndef __attribute__
177 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
178 # define __attribute__(x) /* empty */
182 #ifndef ATTRIBUTE_UNUSED
183 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
186 /* If this host provides the openat function, then we can avoid
187 attempting to open "." in some initialization code below. */
189 # define HAVE_OPENAT_SUPPORT 1
191 # define HAVE_OPENAT_SUPPORT 0
195 # define fts_assert(expr) ((void) 0)
197 # define fts_assert(expr) \
206 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
207 static FTSENT *fts_build (FTS *, int) internal_function;
208 static void fts_lfree (FTSENT *) internal_function;
209 static void fts_load (FTS *, FTSENT *) internal_function;
210 static size_t fts_maxarglen (char * const *) internal_function;
211 static void fts_padjust (FTS *, FTSENT *) internal_function;
212 static bool fts_palloc (FTS *, size_t) internal_function;
213 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
214 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
215 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
219 # include "fts-cycle.c"
221 static bool enter_dir (FTS *fts, FTSENT *ent) { return true; }
222 static void leave_dir (FTS *fts, FTSENT *ent) {}
223 static bool setup_dir (FTS *fts) { return true; }
224 static void free_dir (FTS *fts) {}
228 # define MAX(a,b) ((a) > (b) ? (a) : (b))
232 # define SIZE_MAX ((size_t) -1)
235 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
236 #define STREQ(a, b) (strcmp ((a), (b)) == 0)
238 #define CLR(opt) (sp->fts_options &= ~(opt))
239 #define ISSET(opt) (sp->fts_options & (opt))
240 #define SET(opt) (sp->fts_options |= (opt))
242 /* FIXME: make this a function */
243 #define RESTORE_INITIAL_CWD(sp) \
244 (fd_ring_clear (&((sp)->fts_fd_ring)), \
245 FCHDIR ((sp), (ISSET (FTS_CWDFD) ? AT_FDCWD : (sp)->fts_rfd)))
247 /* FIXME: FTS_NOCHDIR is now misnamed.
248 Call it FTS_USE_FULL_RELATIVE_FILE_NAMES instead. */
249 #define FCHDIR(sp, fd) \
250 (!ISSET(FTS_NOCHDIR) && (ISSET(FTS_CWDFD) \
251 ? (cwd_advance_fd ((sp), (fd), true), 0) \
255 /* fts_build flags */
256 /* FIXME: make this an enum */
257 #define BCHILD 1 /* fts_children */
258 #define BNAMES 2 /* fts_children, names only */
259 #define BREAD 3 /* fts_read */
262 # include <inttypes.h>
265 # include "getcwdat.h"
266 bool fts_debug = false;
267 # define Dprintf(x) do { if (fts_debug) printf x; } while (false)
270 # define fd_ring_check(x)
271 # define fd_ring_print(a, b, c)
274 #define LEAVE_DIR(Fts, Ent, Tag) \
277 Dprintf ((" %s-leaving: %s\n", Tag, (Ent)->fts_path)); \
278 leave_dir (Fts, Ent); \
279 fd_ring_check (Fts); \
284 fd_ring_clear (I_ring *fd_ring)
286 while ( ! i_ring_empty (fd_ring))
288 int fd = i_ring_pop (fd_ring);
294 /* Overload the fts_statp->st_size member (otherwise unused, when
295 fts_info is FTS_NSOK) to indicate whether fts_read should stat
296 this entry or not. */
298 fts_set_stat_required (FTSENT *p, bool required)
300 fts_assert (p->fts_info == FTS_NSOK);
301 p->fts_statp->st_size = (required
303 : FTS_NO_STAT_REQUIRED);
306 /* file-descriptor-relative opendir. */
307 /* FIXME: if others need this function, move it into lib/openat.c */
310 opendirat (int fd, char const *dir)
312 int new_fd = openat (fd, dir,
313 O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK);
318 set_cloexec_flag (new_fd, true);
319 dirp = fdopendir (new_fd);
322 int saved_errno = errno;
329 /* Virtual fchdir. Advance SP's working directory file descriptor,
330 SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
331 CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory
332 open on sp->fts_cwd_fd; i.e., to move the working directory one level
336 cwd_advance_fd (FTS *sp, int fd, bool chdir_down_one)
338 int old = sp->fts_cwd_fd;
339 fts_assert (old != fd || old == AT_FDCWD);
343 /* Push "old" onto the ring.
344 If the displaced file descriptor is non-negative, close it. */
345 int prev_fd_in_slot = i_ring_push (&sp->fts_fd_ring, old);
346 fd_ring_print (sp, stderr, "post-push");
347 if (0 <= prev_fd_in_slot)
348 close (prev_fd_in_slot); /* ignore any close failure */
350 else if ( ! ISSET (FTS_NOCHDIR))
353 close (old); /* ignore any close failure */
359 /* Open the directory DIR if possible, and return a file
360 descriptor. Return -1 and set errno on failure. It doesn't matter
361 whether the file descriptor has read or write access. */
365 diropen (FTS const *sp, char const *dir)
367 int open_flags = (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
368 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0));
370 int fd = (ISSET (FTS_CWDFD)
371 ? openat (sp->fts_cwd_fd, dir, open_flags)
372 : open (dir, open_flags));
374 set_cloexec_flag (fd, true);
379 fts_open (char * const *argv,
380 register int options,
381 int (*compar) (FTSENT const **, FTSENT const **))
384 register FTSENT *p, *root;
385 register size_t nitems;
386 FTSENT *parent = NULL;
387 FTSENT *tmp = NULL; /* pacify gcc */
392 if (options & ~FTS_OPTIONMASK) {
393 __set_errno (EINVAL);
396 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
397 __set_errno (EINVAL);
400 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
401 __set_errno (EINVAL);
405 /* Allocate/initialize the stream */
406 if ((sp = malloc(sizeof(FTS))) == NULL)
408 memset(sp, 0, sizeof(FTS));
409 sp->fts_compar = compar;
410 sp->fts_options = options;
412 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
413 if (ISSET(FTS_LOGICAL)) {
418 /* Initialize fts_cwd_fd. */
419 sp->fts_cwd_fd = AT_FDCWD;
420 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
422 /* While it isn't technically necessary to open "." this
423 early, doing it here saves us the trouble of ensuring
424 later (where it'd be messier) that "." can in fact
425 be opened. If not, revert to FTS_NOCHDIR mode. */
426 int fd = open (".", O_RDONLY);
429 /* Even if `.' is unreadable, don't revert to FTS_NOCHDIR mode
430 on systems like Linux+PROC_FS, where our openat emulation
431 is good enough. Note: on a system that emulates
432 openat via /proc, this technique can still fail, but
433 only in extreme conditions, e.g., when the working
434 directory cannot be saved (i.e. save_cwd fails) --
435 and that happens on Linux only when "." is unreadable
436 and the CWD would be longer than PATH_MAX.
437 FIXME: once Linux kernel openat support is well established,
438 replace the above open call and this entire if/else block
439 with the body of the if-block below. */
440 if ( openat_needs_fchdir ())
453 * Start out with 1K of file name space, and enough, in any case,
454 * to hold the user's file names.
457 # define MAXPATHLEN 1024
460 size_t maxarglen = fts_maxarglen(argv);
461 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
465 /* Allocate/initialize root's parent. */
467 if ((parent = fts_alloc(sp, "", 0)) == NULL)
469 parent->fts_level = FTS_ROOTPARENTLEVEL;
472 /* The classic fts implementation would call fts_stat with
473 a new entry for each iteration of the loop below.
474 If the comparison function is not specified or if the
475 FTS_DEFER_STAT option is in effect, don't stat any entry
476 in this loop. This is an attempt to minimize the interval
477 between the initial stat/lstat/fstatat and the point at which
478 a directory argument is first opened. This matters for any
479 directory command line argument that resides on a file system
480 without genuine i-nodes. If you specify FTS_DEFER_STAT along
481 with a comparison function, that function must not access any
482 data via the fts_statp pointer. */
483 defer_stat = (compar == NULL || ISSET(FTS_DEFER_STAT));
485 /* Allocate/initialize root(s). */
486 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
487 /* Don't allow zero-length file names. */
488 if ((len = strlen(*argv)) == 0) {
489 __set_errno (ENOENT);
493 if ((p = fts_alloc(sp, *argv, len)) == NULL)
495 p->fts_level = FTS_ROOTLEVEL;
496 p->fts_parent = parent;
497 p->fts_accpath = p->fts_name;
498 /* Even when defer_stat is true, be sure to stat the first
499 command line argument, since fts_read (at least with
500 FTS_XDEV) requires that. */
501 if (defer_stat && root != NULL) {
502 p->fts_info = FTS_NSOK;
503 fts_set_stat_required(p, true);
505 p->fts_info = fts_stat(sp, p, false);
509 * If comparison routine supplied, traverse in sorted
510 * order; otherwise traverse in the order specified.
525 if (compar && nitems > 1)
526 root = fts_sort(sp, root, nitems);
529 * Allocate a dummy pointer and make fts_read think that we've just
530 * finished the node before the root(s); set p->fts_info to FTS_INIT
531 * so that everything about the "current" node is ignored.
533 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
535 sp->fts_cur->fts_link = root;
536 sp->fts_cur->fts_info = FTS_INIT;
537 if (! setup_dir (sp))
541 * If using chdir(2), grab a file descriptor pointing to dot to ensure
542 * that we can get back here; this could be avoided for some file names,
543 * but almost certainly not worth the effort. Slashes, symbolic links,
544 * and ".." are all fairly nasty problems. Note, if we can't get the
545 * descriptor we run anyway, just more slowly.
547 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
548 && (sp->fts_rfd = diropen (sp, ".")) < 0)
551 i_ring_init (&sp->fts_fd_ring, -1);
554 mem3: fts_lfree(root);
556 mem2: free(sp->fts_path);
563 fts_load (FTS *sp, register FTSENT *p)
569 * Load the stream structure for the next traversal. Since we don't
570 * actually enter the directory until after the preorder visit, set
571 * the fts_accpath field specially so the chdir gets done to the right
572 * place and the user can access the first node. From fts_open it's
573 * known that the file name will fit.
575 len = p->fts_pathlen = p->fts_namelen;
576 memmove(sp->fts_path, p->fts_name, len + 1);
577 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
579 memmove(p->fts_name, cp, len + 1);
580 p->fts_namelen = len;
582 p->fts_accpath = p->fts_path = sp->fts_path;
588 register FTSENT *freep, *p;
592 * This still works if we haven't read anything -- the dummy structure
593 * points to the root list, so we step through to the end of the root
594 * list which has a valid parent pointer.
597 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
599 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
605 /* Free up child linked list, sort array, file name buffer. */
607 fts_lfree(sp->fts_child);
611 if (ISSET(FTS_CWDFD))
613 if (0 <= sp->fts_cwd_fd)
614 if (close (sp->fts_cwd_fd))
617 else if (!ISSET(FTS_NOCHDIR))
619 /* Return to original directory, save errno if necessary. */
620 if (fchdir(sp->fts_rfd))
623 /* If close fails, record errno only if saved_errno is zero,
624 so that we report the probably-more-meaningful fchdir errno. */
625 if (close (sp->fts_rfd))
626 if (saved_errno == 0)
630 fd_ring_clear (&sp->fts_fd_ring);
633 if (sp->fts_leaf_optimization_works_ht)
634 hash_free (sp->fts_leaf_optimization_works_ht);
639 /* Free up the stream pointer. */
642 /* Set errno and return. */
644 __set_errno (saved_errno);
651 #if defined __linux__ \
652 && HAVE_SYS_VFS_H && HAVE_FSTATFS && HAVE_STRUCT_STATFS_F_TYPE
656 /* Linux-specific constants from coreutils' src/fs.h */
657 # define S_MAGIC_TMPFS 0x1021994
658 # define S_MAGIC_NFS 0x6969
659 # define S_MAGIC_REISERFS 0x52654973
660 # define S_MAGIC_PROC 0x9FA0
662 /* Return false if it is easy to determine the file system type of
663 the directory on which DIR_FD is open, and sorting dirents on
664 inode numbers is known not to improve traversal performance with
665 that type of file system. Otherwise, return true. */
667 dirent_inode_sort_may_be_useful (int dir_fd)
669 /* Skip the sort only if we can determine efficiently
670 that skipping it is the right thing to do.
671 The cost of performing an unnecessary sort is negligible,
672 while the cost of *not* performing it can be O(N^2) with
673 a very large constant. */
674 struct statfs fs_buf;
676 /* If fstatfs fails, assume sorting would be useful. */
677 if (fstatfs (dir_fd, &fs_buf) != 0)
680 /* FIXME: what about when f_type is not an integral type?
681 deal with that if/when it's encountered. */
682 switch (fs_buf.f_type)
686 /* On a file system of any of these types, sorting
687 is unnecessary, and hence wasteful. */
695 /* Given a file descriptor DIR_FD open on a directory D,
696 return true if it is valid to apply the leaf-optimization
697 technique of counting directories in D via stat.st_nlink. */
699 leaf_optimization_applies (int dir_fd)
701 struct statfs fs_buf;
703 /* If fstatfs fails, assume we can't use the optimization. */
704 if (fstatfs (dir_fd, &fs_buf) != 0)
707 /* FIXME: do we need to detect AFS mount points? I doubt it,
708 unless fstatfs can report S_MAGIC_REISERFS for such a directory. */
710 switch (fs_buf.f_type)
712 /* List here the file system types that lack useable dirent.d_type
713 info, yet for which the optimization does apply. */
714 case S_MAGIC_REISERFS:
718 /* Explicitly listing this or any other file system type for which
719 the optimization is not applicable is not necessary, but we leave
720 it here to document the risk. Per http://bugs.debian.org/143111,
721 /proc may have bogus stat.st_nlink values. */
729 static bool dirent_inode_sort_may_be_useful (int dir_fd) { return true; }
730 static bool leaf_optimization_applies (int dir_fd) { return false; }
734 /* link-count-optimization entry:
735 map an stat.st_dev number to a boolean: leaf_optimization_works */
742 /* Use a tiny initial size. If a traversal encounters more than
743 a few devices, the cost of growing/rehashing this table will be
744 rendered negligible by the number of inodes processed. */
745 enum { LCO_HT_INITIAL_SIZE = 13 };
748 LCO_hash (void const *x, size_t table_size)
750 struct LCO_ent const *ax = x;
751 return (uintmax_t) ax->st_dev % table_size;
755 LCO_compare (void const *x, void const *y)
757 struct LCO_ent const *ax = x;
758 struct LCO_ent const *ay = y;
759 return ax->st_dev == ay->st_dev;
762 /* Ask the same question as leaf_optimization_applies, but query
763 the cache first (FTS.fts_leaf_optimization_works_ht), and if necessary,
764 update that cache. */
766 link_count_optimize_ok (FTSENT const *p)
768 FTS *sp = p->fts_fts;
769 Hash_table *h = sp->fts_leaf_optimization_works_ht;
775 /* If we're not in CWDFD mode, don't bother with this optimization,
776 since the caller is not serious about performance. */
777 if (!ISSET(FTS_CWDFD))
780 /* map st_dev to the boolean, leaf_optimization_works */
783 h = sp->fts_leaf_optimization_works_ht
784 = hash_initialize (LCO_HT_INITIAL_SIZE, NULL, LCO_hash,
789 tmp.st_dev = p->fts_statp->st_dev;
790 ent = hash_lookup (h, &tmp);
794 /* Look-up failed. Query directly and cache the result. */
795 t2 = malloc (sizeof *t2);
799 /* Is it ok to perform the optimization in the dir, FTS_CWD_FD? */
800 opt_ok = leaf_optimization_applies (sp->fts_cwd_fd);
802 t2->st_dev = p->fts_statp->st_dev;
804 ent = hash_insert (h, t2);
807 /* insertion failed */
811 fts_assert (ent == t2);
818 * Special case of "/" at the end of the file name so that slashes aren't
819 * appended which would cause file names to be written as "....//foo".
822 (p->fts_path[p->fts_pathlen - 1] == '/' \
823 ? p->fts_pathlen - 1 : p->fts_pathlen)
826 fts_read (register FTS *sp)
828 register FTSENT *p, *tmp;
829 register unsigned short int instr;
832 /* If finished or unrecoverable error, return NULL. */
833 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
836 /* Set current node pointer. */
839 /* Save and zero out user instructions. */
840 instr = p->fts_instr;
841 p->fts_instr = FTS_NOINSTR;
843 /* Any type of file may be re-visited; re-stat and re-turn. */
844 if (instr == FTS_AGAIN) {
845 p->fts_info = fts_stat(sp, p, false);
848 Dprintf (("fts_read: p=%s\n",
849 p->fts_info == FTS_INIT ? "" : p->fts_path));
852 * Following a symlink -- SLNONE test allows application to see
853 * SLNONE and recover. If indirecting through a symlink, have
854 * keep a pointer to current location. If unable to get that
855 * pointer, follow fails.
857 if (instr == FTS_FOLLOW &&
858 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
859 p->fts_info = fts_stat(sp, p, true);
860 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
861 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
862 p->fts_errno = errno;
863 p->fts_info = FTS_ERR;
865 p->fts_flags |= FTS_SYMFOLLOW;
870 /* Directory in pre-order. */
871 if (p->fts_info == FTS_D) {
872 /* If skipped or crossed mount point, do post-order visit. */
873 if (instr == FTS_SKIP ||
874 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
875 if (p->fts_flags & FTS_SYMFOLLOW)
876 (void)close(p->fts_symfd);
878 fts_lfree(sp->fts_child);
879 sp->fts_child = NULL;
881 p->fts_info = FTS_DP;
882 LEAVE_DIR (sp, p, "1");
886 /* Rebuild if only read the names and now traversing. */
887 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
889 fts_lfree(sp->fts_child);
890 sp->fts_child = NULL;
894 * Cd to the subdirectory.
896 * If have already read and now fail to chdir, whack the list
897 * to make the names come out right, and set the parent errno
898 * so the application will eventually get an error condition.
899 * Set the FTS_DONTCHDIR flag so that when we logically change
900 * directories back to the parent we don't do a chdir.
902 * If haven't read do so. If the read fails, fts_build sets
903 * FTS_STOP or the fts_info field of the node.
905 if (sp->fts_child != NULL) {
906 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
907 p->fts_errno = errno;
908 p->fts_flags |= FTS_DONTCHDIR;
909 for (p = sp->fts_child; p != NULL;
912 p->fts_parent->fts_accpath;
914 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
917 /* If fts_build's call to fts_safe_changedir failed
918 because it was not able to fchdir into a
919 subdirectory, tell the caller. */
920 if (p->fts_errno && p->fts_info != FTS_DNR)
921 p->fts_info = FTS_ERR;
922 LEAVE_DIR (sp, p, "2");
926 sp->fts_child = NULL;
930 /* Move to the next node on this level. */
932 if ((p = p->fts_link) != NULL) {
937 * If reached the top, return to the original directory (or
938 * the root of the tree), and load the file names for the next
941 if (p->fts_level == FTS_ROOTLEVEL) {
942 if (RESTORE_INITIAL_CWD(sp)) {
953 * User may have called fts_set on the node. If skipped,
954 * ignore. If followed, get a file descriptor so we can
955 * get back if necessary.
957 if (p->fts_instr == FTS_SKIP)
959 if (p->fts_instr == FTS_FOLLOW) {
960 p->fts_info = fts_stat(sp, p, true);
961 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
962 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
963 p->fts_errno = errno;
964 p->fts_info = FTS_ERR;
966 p->fts_flags |= FTS_SYMFOLLOW;
968 p->fts_instr = FTS_NOINSTR;
971 name: t = sp->fts_path + NAPPEND(p->fts_parent);
973 memmove(t, p->fts_name, p->fts_namelen + 1);
976 if (p->fts_info == FTS_NSOK)
978 if (p->fts_statp->st_size == FTS_STAT_REQUIRED)
980 FTSENT *parent = p->fts_parent;
981 if (FTS_ROOTLEVEL < p->fts_level
982 /* ->fts_n_dirs_remaining is not valid
983 for command-line-specified names. */
984 && parent->fts_n_dirs_remaining == 0
986 && ISSET(FTS_PHYSICAL)
987 && link_count_optimize_ok (parent))
989 /* nothing more needed */
993 p->fts_info = fts_stat(sp, p, false);
994 if (S_ISDIR(p->fts_statp->st_mode)
995 && p->fts_level != FTS_ROOTLEVEL
996 && parent->fts_n_dirs_remaining)
997 parent->fts_n_dirs_remaining--;
1001 fts_assert (p->fts_statp->st_size == FTS_NO_STAT_REQUIRED);
1004 if (p->fts_info == FTS_D)
1006 /* Now that P->fts_statp is guaranteed to be valid,
1007 if this is a command-line directory, record its
1008 device number, to be used for FTS_XDEV. */
1009 if (p->fts_level == FTS_ROOTLEVEL)
1010 sp->fts_dev = p->fts_statp->st_dev;
1011 Dprintf ((" entering: %s\n", p->fts_path));
1012 if (! enter_dir (sp, p))
1014 __set_errno (ENOMEM);
1021 /* Move up to the parent node. */
1022 p = tmp->fts_parent;
1026 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
1028 * Done; free everything up and set errno to 0 so the user
1029 * can distinguish between error and EOF.
1033 return (sp->fts_cur = NULL);
1036 fts_assert (p->fts_info != FTS_NSOK);
1038 /* NUL terminate the file name. */
1039 sp->fts_path[p->fts_pathlen] = '\0';
1042 * Return to the parent directory. If at a root node, restore
1043 * the initial working directory. If we came through a symlink,
1044 * go back through the file descriptor. Otherwise, move up
1045 * one level, via "..".
1047 if (p->fts_level == FTS_ROOTLEVEL) {
1048 if (RESTORE_INITIAL_CWD(sp)) {
1049 p->fts_errno = errno;
1052 } else if (p->fts_flags & FTS_SYMFOLLOW) {
1053 if (FCHDIR(sp, p->fts_symfd)) {
1054 int saved_errno = errno;
1055 (void)close(p->fts_symfd);
1056 __set_errno (saved_errno);
1057 p->fts_errno = errno;
1060 (void)close(p->fts_symfd);
1061 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
1062 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
1063 p->fts_errno = errno;
1066 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
1067 if (p->fts_errno == 0)
1068 LEAVE_DIR (sp, p, "3");
1069 return ISSET(FTS_STOP) ? NULL : p;
1073 * Fts_set takes the stream as an argument although it's not used in this
1074 * implementation; it would be necessary if anyone wanted to add global
1075 * semantics to fts using fts_set. An error return is allowed for similar
1080 fts_set(FTS *sp ATTRIBUTE_UNUSED, FTSENT *p, int instr)
1082 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
1083 instr != FTS_NOINSTR && instr != FTS_SKIP) {
1084 __set_errno (EINVAL);
1087 p->fts_instr = instr;
1092 fts_children (register FTS *sp, int instr)
1097 if (instr != 0 && instr != FTS_NAMEONLY) {
1098 __set_errno (EINVAL);
1102 /* Set current node pointer. */
1106 * Errno set to 0 so user can distinguish empty directory from
1111 /* Fatal errors stop here. */
1112 if (ISSET(FTS_STOP))
1115 /* Return logical hierarchy of user's arguments. */
1116 if (p->fts_info == FTS_INIT)
1117 return (p->fts_link);
1120 * If not a directory being visited in pre-order, stop here. Could
1121 * allow FTS_DNR, assuming the user has fixed the problem, but the
1122 * same effect is available with FTS_AGAIN.
1124 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
1127 /* Free up any previous child list. */
1128 if (sp->fts_child != NULL)
1129 fts_lfree(sp->fts_child);
1131 if (instr == FTS_NAMEONLY) {
1138 * If using chdir on a relative file name and called BEFORE fts_read
1139 * does its chdir to the root of a traversal, we can lose -- we need to
1140 * chdir into the subdirectory, and we don't know where the current
1141 * directory is, so we can't get back so that the upcoming chdir by
1142 * fts_read will work.
1144 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
1146 return (sp->fts_child = fts_build(sp, instr));
1148 if ((fd = diropen (sp, ".")) < 0)
1149 return (sp->fts_child = NULL);
1150 sp->fts_child = fts_build(sp, instr);
1151 if (ISSET(FTS_CWDFD))
1153 cwd_advance_fd (sp, fd, true);
1159 int saved_errno = errno;
1161 __set_errno (saved_errno);
1166 return (sp->fts_child);
1169 /* A comparison function to sort on increasing inode number.
1170 For some file system types, sorting either way makes a huge
1171 performance difference for a directory with very many entries,
1172 but sorting on increasing values is slightly better than sorting
1173 on decreasing values. The difference is in the 5% range. */
1175 fts_compare_ino (struct _ftsent const **a, struct _ftsent const **b)
1177 return (a[0]->fts_statp->st_ino < b[0]->fts_statp->st_ino ? -1
1178 : b[0]->fts_statp->st_ino < a[0]->fts_statp->st_ino ? 1 : 0);
1181 /* Map the dirent.d_type value, DTYPE, to the corresponding stat.st_mode
1182 S_IF* bit and set ST.st_mode, thus clearing all other bits in that field. */
1184 set_stat_type (struct stat *st, unsigned int dtype)
1217 * This is the tricky part -- do not casually change *anything* in here. The
1218 * idea is to build the linked list of entries that are used by fts_children
1219 * and fts_read. There are lots of special cases.
1221 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
1222 * set and it's a physical walk (so that symbolic links can't be directories),
1223 * we can do things quickly. First, if it's a 4.4BSD file system, the type
1224 * of the file is in the directory entry. Otherwise, we assume that the number
1225 * of subdirectories in a node is equal to the number of links to the parent.
1226 * The former skips all stat calls. The latter skips stat calls in any leaf
1227 * directories and for any files after the subdirectories in the directory have
1228 * been found, cutting the stat calls by about 2/3.
1232 fts_build (register FTS *sp, int type)
1234 register struct dirent *dp;
1235 register FTSENT *p, *head;
1236 register size_t nitems;
1246 size_t len, maxlen, new_len;
1249 /* Set current node pointer. */
1253 * Open the directory for reading. If this fails, we're done.
1254 * If being called from fts_read, set the fts_info field.
1256 #if defined FTS_WHITEOUT && 0
1257 if (ISSET(FTS_WHITEOUT))
1258 oflag = DTF_NODUP|DTF_REWIND;
1260 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
1262 # define __opendir2(file, flag) \
1263 ( ! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
1264 ? opendirat(sp->fts_cwd_fd, file) \
1267 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
1268 if (type == BREAD) {
1269 cur->fts_info = FTS_DNR;
1270 cur->fts_errno = errno;
1274 /* Rather than calling fts_stat for each and every entry encountered
1275 in the readdir loop (below), stat each directory only right after
1277 if (cur->fts_info == FTS_NSOK)
1278 cur->fts_info = fts_stat(sp, cur, false);
1281 * Nlinks is the number of possible entries of type directory in the
1282 * directory if we're cheating on stat calls, 0 if we're not doing
1283 * any stat calls at all, (nlink_t) -1 if we're statting everything.
1285 if (type == BNAMES) {
1287 /* Be quiet about nostat, GCC. */
1289 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
1290 nlinks = (cur->fts_statp->st_nlink
1291 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1299 * If we're going to need to stat anything or we want to descend
1300 * and stay in the directory, chdir. If this fails we keep going,
1301 * but set a flag so we don't chdir after the post-order visit.
1302 * We won't be able to stat anything, but we can still return the
1303 * names themselves. Note, that since fts_read won't be able to
1304 * chdir into the directory, it will have to return different file
1305 * names than before, i.e. "a/b" instead of "b". Since the node
1306 * has already been visited in pre-order, have to wait until the
1307 * post-order visit to return the error. There is a special case
1308 * here, if there was nothing to stat then it's not an error to
1309 * not be able to stat. This is all fairly nasty. If a program
1310 * needed sorted entries or stat information, they had better be
1311 * checking FTS_NS on the returned nodes.
1313 if (nlinks || type == BREAD) {
1314 int dir_fd = dirfd(dirp);
1315 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1317 dir_fd = dup (dir_fd);
1318 set_cloexec_flag (dir_fd, true);
1320 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1321 if (nlinks && type == BREAD)
1322 cur->fts_errno = errno;
1323 cur->fts_flags |= FTS_DONTCHDIR;
1326 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1335 * Figure out the max file name length that can be stored in the
1336 * current buffer -- the inner loop allocates more space as necessary.
1337 * We really wouldn't have to do the maxlen calculations here, we
1338 * could do them in fts_read before returning the name, but it's a
1339 * lot easier here since the length is part of the dirent structure.
1341 * If not changing directories set a pointer so that can just append
1342 * each new component into the file name.
1345 if (ISSET(FTS_NOCHDIR)) {
1346 cp = sp->fts_path + len;
1349 /* GCC, you're too verbose. */
1353 maxlen = sp->fts_pathlen - len;
1355 level = cur->fts_level + 1;
1357 /* Read the directory, attaching each entry to the `link' pointer. */
1359 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
1362 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1365 if ((p = fts_alloc (sp, dp->d_name,
1366 _D_EXACT_NAMLEN (dp))) == NULL)
1368 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
1369 /* include space for NUL */
1370 oldaddr = sp->fts_path;
1371 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
1373 * No more memory. Save
1374 * errno, free up the current structure and the
1375 * structures already allocated.
1377 mem1: saved_errno = errno;
1381 cur->fts_info = FTS_ERR;
1383 __set_errno (saved_errno);
1386 /* Did realloc() change the pointer? */
1387 if (oldaddr != sp->fts_path) {
1389 if (ISSET(FTS_NOCHDIR))
1390 cp = sp->fts_path + len;
1392 maxlen = sp->fts_pathlen - len;
1395 new_len = len + _D_EXACT_NAMLEN (dp);
1396 if (new_len < len) {
1398 * In the unlikely event that we would end up
1399 * with a file name longer than SIZE_MAX, free up
1400 * the current structure and the structures already
1401 * allocated, then error out with ENAMETOOLONG.
1406 cur->fts_info = FTS_ERR;
1408 __set_errno (ENAMETOOLONG);
1411 p->fts_level = level;
1412 p->fts_parent = sp->fts_cur;
1413 p->fts_pathlen = new_len;
1415 #if defined FTS_WHITEOUT && 0
1416 if (dp->d_type == DT_WHT)
1417 p->fts_flags |= FTS_ISW;
1419 /* Store dirent.d_ino, in case we need to sort
1420 entries before processing them. */
1421 p->fts_statp->st_ino = D_INO (dp);
1423 /* Build a file name for fts_stat to stat. */
1424 if (ISSET(FTS_NOCHDIR)) {
1425 p->fts_accpath = p->fts_path;
1426 memmove(cp, p->fts_name, p->fts_namelen + 1);
1428 p->fts_accpath = p->fts_name;
1430 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1431 /* Record what fts_read will have to do with this
1432 entry. In many cases, it will simply fts_stat it,
1433 but we can take advantage of any d_type information
1434 to optimize away the unnecessary stat calls. I.e.,
1435 if FTS_NOSTAT is in effect and we're not following
1436 symlinks (FTS_PHYSICAL) and d_type indicates this
1437 is *not* a directory, then we won't have to stat it
1438 at all. If it *is* a directory, then (currently)
1439 we stat it regardless, in order to get device and
1440 inode numbers. Some day we might optimize that
1441 away, too, for directories where d_ino is known to
1443 bool skip_stat = (ISSET(FTS_PHYSICAL)
1444 && ISSET(FTS_NOSTAT)
1446 && ! DT_MUST_BE(dp, DT_DIR));
1447 p->fts_info = FTS_NSOK;
1448 /* Propagate dirent.d_type information back
1449 to caller, when possible. */
1450 set_stat_type (p->fts_statp, D_TYPE (dp));
1451 fts_set_stat_required(p, !skip_stat);
1452 is_dir = (ISSET(FTS_PHYSICAL)
1453 && DT_MUST_BE(dp, DT_DIR));
1455 p->fts_info = fts_stat(sp, p, false);
1456 is_dir = (p->fts_info == FTS_D
1457 || p->fts_info == FTS_DC
1458 || p->fts_info == FTS_DOT);
1461 /* Decrement link count if applicable. */
1462 if (nlinks > 0 && is_dir)
1465 /* We walk in directory order so "ls -f" doesn't get upset. */
1479 * If realloc() changed the address of the file name, adjust the
1480 * addresses for the rest of the tree and the dir list.
1483 fts_padjust(sp, head);
1486 * If not changing directories, reset the file name back to original
1489 if (ISSET(FTS_NOCHDIR)) {
1490 if (len == sp->fts_pathlen || nitems == 0)
1496 * If descended after called from fts_children or after called from
1497 * fts_read and nothing found, get back. At the root level we use
1498 * the saved fd; if one of fts_open()'s arguments is a relative name
1499 * to an empty directory, we wind up here with no other way back. If
1500 * can't get back, we're done.
1502 if (descend && (type == BCHILD || !nitems) &&
1503 (cur->fts_level == FTS_ROOTLEVEL
1504 ? RESTORE_INITIAL_CWD(sp)
1505 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1506 cur->fts_info = FTS_ERR;
1512 /* If didn't find anything, return NULL. */
1515 cur->fts_info = FTS_DP;
1520 /* If there are many entries, no sorting function has been specified,
1521 and this file system is of a type that may be slow with a large
1522 number of entries, then sort the directory entries on increasing
1524 if (nitems > _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
1526 && ISSET (FTS_CWDFD)
1527 && dirent_inode_sort_may_be_useful (sp->fts_cwd_fd)) {
1528 sp->fts_compar = fts_compare_ino;
1529 head = fts_sort (sp, head, nitems);
1530 sp->fts_compar = NULL;
1533 /* Sort the entries. */
1534 if (sp->fts_compar && nitems > 1)
1535 head = fts_sort(sp, head, nitems);
1541 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1542 current hierarchy. There should be a directory with dev/inode
1543 matching those of AD. If not, print a lot of diagnostics. */
1545 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1548 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1550 if (ad->ino == ent->fts_statp->st_ino
1551 && ad->dev == ent->fts_statp->st_dev)
1554 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1555 printf ("active dirs:\n");
1557 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1558 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1559 ad->fts_ent->fts_accpath,
1560 (uintmax_t) ad->dev,
1561 (uintmax_t) ad->ino,
1563 (uintmax_t) ent->fts_statp->st_dev,
1564 (uintmax_t) ent->fts_statp->st_ino);
1568 fts_cross_check (FTS const *sp)
1570 FTSENT const *ent = sp->fts_cur;
1572 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1575 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1576 /* Make sure every parent dir is in the tree. */
1577 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1579 struct Active_dir ad;
1580 ad.ino = t->fts_statp->st_ino;
1581 ad.dev = t->fts_statp->st_dev;
1582 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1583 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1586 /* Make sure every dir in the tree is an active dir.
1587 But ENT is not necessarily a directory. If so, just skip this part. */
1588 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1589 && (ent->fts_info == FTS_DP
1590 || ent->fts_info == FTS_D))
1592 struct Active_dir *ad;
1593 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1594 ad = hash_get_next (sp->fts_cycle.ht, ad))
1596 find_matching_ancestor (ent, ad);
1602 same_fd (int fd1, int fd2)
1604 struct stat sb1, sb2;
1605 return (fstat (fd1, &sb1) == 0
1606 && fstat (fd2, &sb2) == 0
1607 && SAME_INODE (sb1, sb2));
1611 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1613 I_ring const *fd_ring = &sp->fts_fd_ring;
1614 unsigned int i = fd_ring->fts_front;
1615 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1616 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1618 if (i_ring_empty (fd_ring))
1623 int fd = fd_ring->fts_fd_ring[i];
1625 fprintf (stream, "%d: %d:\n", i, fd);
1628 char *wd = getcwdat (fd, NULL, 0);
1629 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1632 if (i == fd_ring->fts_back)
1634 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1638 /* Ensure that each file descriptor on the fd_ring matches a
1639 parent, grandparent, etc. of the current working directory. */
1641 fd_ring_check (FTS const *sp)
1646 /* Make a writable copy. */
1647 I_ring fd_w = sp->fts_fd_ring;
1649 int cwd_fd = sp->fts_cwd_fd;
1650 cwd_fd = dup (cwd_fd);
1651 char *dot = getcwdat (cwd_fd, NULL, 0);
1652 error (0, 0, "===== check ===== cwd: %s", dot);
1654 while ( ! i_ring_empty (&fd_w))
1656 int fd = i_ring_pop (&fd_w);
1659 int parent_fd = openat (cwd_fd, "..", O_RDONLY);
1665 if (!same_fd (fd, parent_fd))
1667 char *cwd = getcwdat (fd, NULL, 0);
1668 error (0, errno, "ring : %s", cwd);
1669 char *c2 = getcwdat (parent_fd, NULL, 0);
1670 error (0, errno, "parent: %s", c2);
1683 static unsigned short int
1685 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1687 struct stat *sbp = p->fts_statp;
1690 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1693 #if defined FTS_WHITEOUT && 0
1694 /* check for whiteout */
1695 if (p->fts_flags & FTS_ISW) {
1696 memset(sbp, '\0', sizeof (*sbp));
1697 sbp->st_mode = S_IFWHT;
1703 * If doing a logical walk, or application requested FTS_FOLLOW, do
1704 * a stat(2). If that fails, check for a non-existent symlink. If
1705 * fail, set the errno from the stat call.
1707 if (ISSET(FTS_LOGICAL) || follow) {
1708 if (stat(p->fts_accpath, sbp)) {
1709 saved_errno = errno;
1711 && lstat(p->fts_accpath, sbp) == 0) {
1713 return (FTS_SLNONE);
1715 p->fts_errno = saved_errno;
1718 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1719 AT_SYMLINK_NOFOLLOW)) {
1720 p->fts_errno = errno;
1721 err: memset(sbp, 0, sizeof(struct stat));
1725 if (S_ISDIR(sbp->st_mode)) {
1726 p->fts_n_dirs_remaining = (sbp->st_nlink
1727 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1728 if (ISDOT(p->fts_name)) {
1729 /* Command-line "." and ".." are real directories. */
1730 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1736 * Cycle detection is done by brute force when the directory
1737 * is first encountered. If the tree gets deep enough or the
1738 * number of symbolic links to directories is high enough,
1739 * something faster might be worthwhile.
1743 for (t = p->fts_parent;
1744 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1745 if (sbp->st_ino == t->fts_statp->st_ino
1746 && sbp->st_dev == t->fts_statp->st_dev)
1756 if (S_ISLNK(sbp->st_mode))
1758 if (S_ISREG(sbp->st_mode))
1760 return (FTS_DEFAULT);
1764 fts_compar (void const *a, void const *b)
1766 /* Convert A and B to the correct types, to pacify the compiler, and
1767 for portability to bizarre hosts where "void const *" and "FTSENT
1768 const **" differ in runtime representation. The comparison
1769 function cannot modify *a and *b, but there is no compile-time
1771 FTSENT const **pa = (FTSENT const **) a;
1772 FTSENT const **pb = (FTSENT const **) b;
1773 return pa[0]->fts_fts->fts_compar (pa, pb);
1778 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1780 register FTSENT **ap, *p;
1782 /* On most modern hosts, void * and FTSENT ** have the same
1783 run-time representation, and one can convert sp->fts_compar to
1784 the type qsort expects without problem. Use the heuristic that
1785 this is OK if the two pointer types are the same size, and if
1786 converting FTSENT ** to long int is the same as converting
1787 FTSENT ** to void * and then to long int. This heuristic isn't
1788 valid in general but we don't know of any counterexamples. */
1790 int (*compare) (void const *, void const *) =
1791 ((sizeof &dummy == sizeof (void *)
1792 && (long int) &dummy == (long int) (void *) &dummy)
1793 ? (int (*) (void const *, void const *)) sp->fts_compar
1797 * Construct an array of pointers to the structures and call qsort(3).
1798 * Reassemble the array in the order returned by qsort. If unable to
1799 * sort for memory reasons, return the directory entries in their
1800 * current order. Allocate enough space for the current needs plus
1801 * 40 so don't realloc one entry at a time.
1803 if (nitems > sp->fts_nitems) {
1806 sp->fts_nitems = nitems + 40;
1807 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1808 || ! (a = realloc (sp->fts_array,
1809 sp->fts_nitems * sizeof *a))) {
1810 free(sp->fts_array);
1811 sp->fts_array = NULL;
1817 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1819 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1820 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1821 ap[0]->fts_link = ap[1];
1822 ap[0]->fts_link = NULL;
1828 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1834 * The file name is a variable length array. Allocate the FTSENT
1835 * structure and the file name in one chunk.
1837 len = sizeof(FTSENT) + namelen;
1838 if ((p = malloc(len)) == NULL)
1841 /* Copy the name and guarantee NUL termination. */
1842 memmove(p->fts_name, name, namelen);
1843 p->fts_name[namelen] = '\0';
1845 p->fts_namelen = namelen;
1847 p->fts_path = sp->fts_path;
1850 p->fts_instr = FTS_NOINSTR;
1852 p->fts_pointer = NULL;
1858 fts_lfree (register FTSENT *head)
1862 /* Free a linked list of structures. */
1863 while ((p = head)) {
1864 head = head->fts_link;
1870 * Allow essentially unlimited file name lengths; find, rm, ls should
1871 * all work on any tree. Most systems will allow creation of file
1872 * names much longer than MAXPATHLEN, even though the kernel won't
1873 * resolve them. Add the size (not just what's needed) plus 256 bytes
1874 * so don't realloc the file name 2 bytes at a time.
1878 fts_palloc (FTS *sp, size_t more)
1881 size_t new_len = sp->fts_pathlen + more + 256;
1884 * See if fts_pathlen would overflow.
1886 if (new_len < sp->fts_pathlen) {
1888 sp->fts_path = NULL;
1889 __set_errno (ENAMETOOLONG);
1892 sp->fts_pathlen = new_len;
1893 p = realloc(sp->fts_path, sp->fts_pathlen);
1896 sp->fts_path = NULL;
1904 * When the file name is realloc'd, have to fix all of the pointers in
1905 * structures already returned.
1909 fts_padjust (FTS *sp, FTSENT *head)
1912 char *addr = sp->fts_path;
1914 #define ADJUST(p) do { \
1915 if ((p)->fts_accpath != (p)->fts_name) { \
1916 (p)->fts_accpath = \
1917 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1919 (p)->fts_path = addr; \
1921 /* Adjust the current set of children. */
1922 for (p = sp->fts_child; p; p = p->fts_link)
1925 /* Adjust the rest of the tree, including the current level. */
1926 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1928 p = p->fts_link ? p->fts_link : p->fts_parent;
1934 fts_maxarglen (char * const *argv)
1938 for (max = 0; *argv; ++argv)
1939 if ((len = strlen(*argv)) > max)
1945 * Change to dir specified by fd or file name without getting
1946 * tricked by someone changing the world out from underneath us.
1947 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
1948 * If FD is non-negative, expect it to be used after this function returns,
1949 * and to be closed eventually. So don't pass e.g., `dirfd(dirp)' and then
1950 * do closedir(dirp), because that would invalidate the saved FD.
1951 * Upon failure, close FD immediately and return nonzero.
1955 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
1958 bool is_dotdot = dir && STREQ (dir, "..");
1961 /* This clause handles the unusual case in which FTS_NOCHDIR
1962 is specified, along with FTS_CWDFD. In that case, there is
1963 no need to change even the virtual cwd file descriptor.
1964 However, if FD is non-negative, we do close it here. */
1965 if (ISSET (FTS_NOCHDIR))
1967 if (ISSET (FTS_CWDFD) && 0 <= fd)
1972 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
1974 /* When possible, skip the diropen and subsequent fstat+dev/ino
1975 comparison. I.e., when changing to parent directory
1976 (chdir ("..")), use a file descriptor from the ring and
1977 save the overhead of diropen+fstat, as well as avoiding
1978 failure when we lack "x" access to the virtual cwd. */
1979 if ( ! i_ring_empty (&sp->fts_fd_ring))
1982 fd_ring_print (sp, stderr, "pre-pop");
1983 parent_fd = i_ring_pop (&sp->fts_fd_ring);
1994 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
1997 /* The following dev/inode check is necessary if we're doing a
1998 `logical' traversal (through symlinks, a la chown -L), if the
1999 system lacks O_NOFOLLOW support, or if we're changing to ".."
2000 (but not via a popped file descriptor). When changing to the
2001 name "..", O_NOFOLLOW can't help. In general, when the target is
2002 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
2003 follow a symlink, so we can avoid the expense of this fstat. */
2004 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
2005 || (dir && STREQ (dir, "..")))
2008 if (fstat(newfd, &sb))
2013 if (p->fts_statp->st_dev != sb.st_dev
2014 || p->fts_statp->st_ino != sb.st_ino)
2016 __set_errno (ENOENT); /* disinformation */
2022 if (ISSET(FTS_CWDFD))
2024 cwd_advance_fd (sp, newfd, ! is_dotdot);
2028 ret = fchdir(newfd);
2034 __set_errno (oerrno);