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. */
730 dirent_inode_sort_may_be_useful (int dir_fd ATTRIBUTE_UNUSED) { return true; }
732 leaf_optimization_applies (int dir_fd ATTRIBUTE_UNUSED) { return false; }
736 /* link-count-optimization entry:
737 map an stat.st_dev number to a boolean: leaf_optimization_works */
744 /* Use a tiny initial size. If a traversal encounters more than
745 a few devices, the cost of growing/rehashing this table will be
746 rendered negligible by the number of inodes processed. */
747 enum { LCO_HT_INITIAL_SIZE = 13 };
750 LCO_hash (void const *x, size_t table_size)
752 struct LCO_ent const *ax = x;
753 return (uintmax_t) ax->st_dev % table_size;
757 LCO_compare (void const *x, void const *y)
759 struct LCO_ent const *ax = x;
760 struct LCO_ent const *ay = y;
761 return ax->st_dev == ay->st_dev;
764 /* Ask the same question as leaf_optimization_applies, but query
765 the cache first (FTS.fts_leaf_optimization_works_ht), and if necessary,
766 update that cache. */
768 link_count_optimize_ok (FTSENT const *p)
770 FTS *sp = p->fts_fts;
771 Hash_table *h = sp->fts_leaf_optimization_works_ht;
777 /* If we're not in CWDFD mode, don't bother with this optimization,
778 since the caller is not serious about performance. */
779 if (!ISSET(FTS_CWDFD))
782 /* map st_dev to the boolean, leaf_optimization_works */
785 h = sp->fts_leaf_optimization_works_ht
786 = hash_initialize (LCO_HT_INITIAL_SIZE, NULL, LCO_hash,
791 tmp.st_dev = p->fts_statp->st_dev;
792 ent = hash_lookup (h, &tmp);
796 /* Look-up failed. Query directly and cache the result. */
797 t2 = malloc (sizeof *t2);
801 /* Is it ok to perform the optimization in the dir, FTS_CWD_FD? */
802 opt_ok = leaf_optimization_applies (sp->fts_cwd_fd);
804 t2->st_dev = p->fts_statp->st_dev;
806 ent = hash_insert (h, t2);
809 /* insertion failed */
813 fts_assert (ent == t2);
820 * Special case of "/" at the end of the file name so that slashes aren't
821 * appended which would cause file names to be written as "....//foo".
824 (p->fts_path[p->fts_pathlen - 1] == '/' \
825 ? p->fts_pathlen - 1 : p->fts_pathlen)
828 fts_read (register FTS *sp)
830 register FTSENT *p, *tmp;
831 register unsigned short int instr;
834 /* If finished or unrecoverable error, return NULL. */
835 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
838 /* Set current node pointer. */
841 /* Save and zero out user instructions. */
842 instr = p->fts_instr;
843 p->fts_instr = FTS_NOINSTR;
845 /* Any type of file may be re-visited; re-stat and re-turn. */
846 if (instr == FTS_AGAIN) {
847 p->fts_info = fts_stat(sp, p, false);
850 Dprintf (("fts_read: p=%s\n",
851 p->fts_info == FTS_INIT ? "" : p->fts_path));
854 * Following a symlink -- SLNONE test allows application to see
855 * SLNONE and recover. If indirecting through a symlink, have
856 * keep a pointer to current location. If unable to get that
857 * pointer, follow fails.
859 if (instr == FTS_FOLLOW &&
860 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
861 p->fts_info = fts_stat(sp, p, true);
862 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
863 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
864 p->fts_errno = errno;
865 p->fts_info = FTS_ERR;
867 p->fts_flags |= FTS_SYMFOLLOW;
872 /* Directory in pre-order. */
873 if (p->fts_info == FTS_D) {
874 /* If skipped or crossed mount point, do post-order visit. */
875 if (instr == FTS_SKIP ||
876 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
877 if (p->fts_flags & FTS_SYMFOLLOW)
878 (void)close(p->fts_symfd);
880 fts_lfree(sp->fts_child);
881 sp->fts_child = NULL;
883 p->fts_info = FTS_DP;
884 LEAVE_DIR (sp, p, "1");
888 /* Rebuild if only read the names and now traversing. */
889 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
891 fts_lfree(sp->fts_child);
892 sp->fts_child = NULL;
896 * Cd to the subdirectory.
898 * If have already read and now fail to chdir, whack the list
899 * to make the names come out right, and set the parent errno
900 * so the application will eventually get an error condition.
901 * Set the FTS_DONTCHDIR flag so that when we logically change
902 * directories back to the parent we don't do a chdir.
904 * If haven't read do so. If the read fails, fts_build sets
905 * FTS_STOP or the fts_info field of the node.
907 if (sp->fts_child != NULL) {
908 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
909 p->fts_errno = errno;
910 p->fts_flags |= FTS_DONTCHDIR;
911 for (p = sp->fts_child; p != NULL;
914 p->fts_parent->fts_accpath;
916 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
919 /* If fts_build's call to fts_safe_changedir failed
920 because it was not able to fchdir into a
921 subdirectory, tell the caller. */
922 if (p->fts_errno && p->fts_info != FTS_DNR)
923 p->fts_info = FTS_ERR;
924 LEAVE_DIR (sp, p, "2");
928 sp->fts_child = NULL;
932 /* Move to the next node on this level. */
934 if ((p = p->fts_link) != NULL) {
939 * If reached the top, return to the original directory (or
940 * the root of the tree), and load the file names for the next
943 if (p->fts_level == FTS_ROOTLEVEL) {
944 if (RESTORE_INITIAL_CWD(sp)) {
955 * User may have called fts_set on the node. If skipped,
956 * ignore. If followed, get a file descriptor so we can
957 * get back if necessary.
959 if (p->fts_instr == FTS_SKIP)
961 if (p->fts_instr == FTS_FOLLOW) {
962 p->fts_info = fts_stat(sp, p, true);
963 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
964 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
965 p->fts_errno = errno;
966 p->fts_info = FTS_ERR;
968 p->fts_flags |= FTS_SYMFOLLOW;
970 p->fts_instr = FTS_NOINSTR;
973 name: t = sp->fts_path + NAPPEND(p->fts_parent);
975 memmove(t, p->fts_name, p->fts_namelen + 1);
978 if (p->fts_info == FTS_NSOK)
980 if (p->fts_statp->st_size == FTS_STAT_REQUIRED)
982 FTSENT *parent = p->fts_parent;
983 if (FTS_ROOTLEVEL < p->fts_level
984 /* ->fts_n_dirs_remaining is not valid
985 for command-line-specified names. */
986 && parent->fts_n_dirs_remaining == 0
988 && ISSET(FTS_PHYSICAL)
989 && link_count_optimize_ok (parent))
991 /* nothing more needed */
995 p->fts_info = fts_stat(sp, p, false);
996 if (S_ISDIR(p->fts_statp->st_mode)
997 && p->fts_level != FTS_ROOTLEVEL
998 && parent->fts_n_dirs_remaining)
999 parent->fts_n_dirs_remaining--;
1003 fts_assert (p->fts_statp->st_size == FTS_NO_STAT_REQUIRED);
1006 if (p->fts_info == FTS_D)
1008 /* Now that P->fts_statp is guaranteed to be valid,
1009 if this is a command-line directory, record its
1010 device number, to be used for FTS_XDEV. */
1011 if (p->fts_level == FTS_ROOTLEVEL)
1012 sp->fts_dev = p->fts_statp->st_dev;
1013 Dprintf ((" entering: %s\n", p->fts_path));
1014 if (! enter_dir (sp, p))
1016 __set_errno (ENOMEM);
1023 /* Move up to the parent node. */
1024 p = tmp->fts_parent;
1028 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
1030 * Done; free everything up and set errno to 0 so the user
1031 * can distinguish between error and EOF.
1035 return (sp->fts_cur = NULL);
1038 fts_assert (p->fts_info != FTS_NSOK);
1040 /* NUL terminate the file name. */
1041 sp->fts_path[p->fts_pathlen] = '\0';
1044 * Return to the parent directory. If at a root node, restore
1045 * the initial working directory. If we came through a symlink,
1046 * go back through the file descriptor. Otherwise, move up
1047 * one level, via "..".
1049 if (p->fts_level == FTS_ROOTLEVEL) {
1050 if (RESTORE_INITIAL_CWD(sp)) {
1051 p->fts_errno = errno;
1054 } else if (p->fts_flags & FTS_SYMFOLLOW) {
1055 if (FCHDIR(sp, p->fts_symfd)) {
1056 int saved_errno = errno;
1057 (void)close(p->fts_symfd);
1058 __set_errno (saved_errno);
1059 p->fts_errno = errno;
1062 (void)close(p->fts_symfd);
1063 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
1064 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
1065 p->fts_errno = errno;
1068 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
1069 if (p->fts_errno == 0)
1070 LEAVE_DIR (sp, p, "3");
1071 return ISSET(FTS_STOP) ? NULL : p;
1075 * Fts_set takes the stream as an argument although it's not used in this
1076 * implementation; it would be necessary if anyone wanted to add global
1077 * semantics to fts using fts_set. An error return is allowed for similar
1082 fts_set(FTS *sp ATTRIBUTE_UNUSED, FTSENT *p, int instr)
1084 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
1085 instr != FTS_NOINSTR && instr != FTS_SKIP) {
1086 __set_errno (EINVAL);
1089 p->fts_instr = instr;
1094 fts_children (register FTS *sp, int instr)
1099 if (instr != 0 && instr != FTS_NAMEONLY) {
1100 __set_errno (EINVAL);
1104 /* Set current node pointer. */
1108 * Errno set to 0 so user can distinguish empty directory from
1113 /* Fatal errors stop here. */
1114 if (ISSET(FTS_STOP))
1117 /* Return logical hierarchy of user's arguments. */
1118 if (p->fts_info == FTS_INIT)
1119 return (p->fts_link);
1122 * If not a directory being visited in pre-order, stop here. Could
1123 * allow FTS_DNR, assuming the user has fixed the problem, but the
1124 * same effect is available with FTS_AGAIN.
1126 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
1129 /* Free up any previous child list. */
1130 if (sp->fts_child != NULL)
1131 fts_lfree(sp->fts_child);
1133 if (instr == FTS_NAMEONLY) {
1140 * If using chdir on a relative file name and called BEFORE fts_read
1141 * does its chdir to the root of a traversal, we can lose -- we need to
1142 * chdir into the subdirectory, and we don't know where the current
1143 * directory is, so we can't get back so that the upcoming chdir by
1144 * fts_read will work.
1146 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
1148 return (sp->fts_child = fts_build(sp, instr));
1150 if ((fd = diropen (sp, ".")) < 0)
1151 return (sp->fts_child = NULL);
1152 sp->fts_child = fts_build(sp, instr);
1153 if (ISSET(FTS_CWDFD))
1155 cwd_advance_fd (sp, fd, true);
1161 int saved_errno = errno;
1163 __set_errno (saved_errno);
1168 return (sp->fts_child);
1171 /* A comparison function to sort on increasing inode number.
1172 For some file system types, sorting either way makes a huge
1173 performance difference for a directory with very many entries,
1174 but sorting on increasing values is slightly better than sorting
1175 on decreasing values. The difference is in the 5% range. */
1177 fts_compare_ino (struct _ftsent const **a, struct _ftsent const **b)
1179 return (a[0]->fts_statp->st_ino < b[0]->fts_statp->st_ino ? -1
1180 : b[0]->fts_statp->st_ino < a[0]->fts_statp->st_ino ? 1 : 0);
1183 /* Map the dirent.d_type value, DTYPE, to the corresponding stat.st_mode
1184 S_IF* bit and set ST.st_mode, thus clearing all other bits in that field. */
1186 set_stat_type (struct stat *st, unsigned int dtype)
1219 * This is the tricky part -- do not casually change *anything* in here. The
1220 * idea is to build the linked list of entries that are used by fts_children
1221 * and fts_read. There are lots of special cases.
1223 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
1224 * set and it's a physical walk (so that symbolic links can't be directories),
1225 * we can do things quickly. First, if it's a 4.4BSD file system, the type
1226 * of the file is in the directory entry. Otherwise, we assume that the number
1227 * of subdirectories in a node is equal to the number of links to the parent.
1228 * The former skips all stat calls. The latter skips stat calls in any leaf
1229 * directories and for any files after the subdirectories in the directory have
1230 * been found, cutting the stat calls by about 2/3.
1234 fts_build (register FTS *sp, int type)
1236 register struct dirent *dp;
1237 register FTSENT *p, *head;
1238 register size_t nitems;
1248 size_t len, maxlen, new_len;
1251 /* Set current node pointer. */
1255 * Open the directory for reading. If this fails, we're done.
1256 * If being called from fts_read, set the fts_info field.
1258 #if defined FTS_WHITEOUT && 0
1259 if (ISSET(FTS_WHITEOUT))
1260 oflag = DTF_NODUP|DTF_REWIND;
1262 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
1264 # define __opendir2(file, flag) \
1265 ( ! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
1266 ? opendirat(sp->fts_cwd_fd, file) \
1269 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
1270 if (type == BREAD) {
1271 cur->fts_info = FTS_DNR;
1272 cur->fts_errno = errno;
1276 /* Rather than calling fts_stat for each and every entry encountered
1277 in the readdir loop (below), stat each directory only right after
1279 if (cur->fts_info == FTS_NSOK)
1280 cur->fts_info = fts_stat(sp, cur, false);
1283 * Nlinks is the number of possible entries of type directory in the
1284 * directory if we're cheating on stat calls, 0 if we're not doing
1285 * any stat calls at all, (nlink_t) -1 if we're statting everything.
1287 if (type == BNAMES) {
1289 /* Be quiet about nostat, GCC. */
1291 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
1292 nlinks = (cur->fts_statp->st_nlink
1293 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1301 * If we're going to need to stat anything or we want to descend
1302 * and stay in the directory, chdir. If this fails we keep going,
1303 * but set a flag so we don't chdir after the post-order visit.
1304 * We won't be able to stat anything, but we can still return the
1305 * names themselves. Note, that since fts_read won't be able to
1306 * chdir into the directory, it will have to return different file
1307 * names than before, i.e. "a/b" instead of "b". Since the node
1308 * has already been visited in pre-order, have to wait until the
1309 * post-order visit to return the error. There is a special case
1310 * here, if there was nothing to stat then it's not an error to
1311 * not be able to stat. This is all fairly nasty. If a program
1312 * needed sorted entries or stat information, they had better be
1313 * checking FTS_NS on the returned nodes.
1315 if (nlinks || type == BREAD) {
1316 int dir_fd = dirfd(dirp);
1317 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1319 dir_fd = dup (dir_fd);
1320 set_cloexec_flag (dir_fd, true);
1322 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1323 if (nlinks && type == BREAD)
1324 cur->fts_errno = errno;
1325 cur->fts_flags |= FTS_DONTCHDIR;
1328 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1337 * Figure out the max file name length that can be stored in the
1338 * current buffer -- the inner loop allocates more space as necessary.
1339 * We really wouldn't have to do the maxlen calculations here, we
1340 * could do them in fts_read before returning the name, but it's a
1341 * lot easier here since the length is part of the dirent structure.
1343 * If not changing directories set a pointer so that can just append
1344 * each new component into the file name.
1347 if (ISSET(FTS_NOCHDIR)) {
1348 cp = sp->fts_path + len;
1351 /* GCC, you're too verbose. */
1355 maxlen = sp->fts_pathlen - len;
1357 level = cur->fts_level + 1;
1359 /* Read the directory, attaching each entry to the `link' pointer. */
1361 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
1364 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1367 if ((p = fts_alloc (sp, dp->d_name,
1368 _D_EXACT_NAMLEN (dp))) == NULL)
1370 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
1371 /* include space for NUL */
1372 oldaddr = sp->fts_path;
1373 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
1375 * No more memory. Save
1376 * errno, free up the current structure and the
1377 * structures already allocated.
1379 mem1: saved_errno = errno;
1383 cur->fts_info = FTS_ERR;
1385 __set_errno (saved_errno);
1388 /* Did realloc() change the pointer? */
1389 if (oldaddr != sp->fts_path) {
1391 if (ISSET(FTS_NOCHDIR))
1392 cp = sp->fts_path + len;
1394 maxlen = sp->fts_pathlen - len;
1397 new_len = len + _D_EXACT_NAMLEN (dp);
1398 if (new_len < len) {
1400 * In the unlikely event that we would end up
1401 * with a file name longer than SIZE_MAX, free up
1402 * the current structure and the structures already
1403 * allocated, then error out with ENAMETOOLONG.
1408 cur->fts_info = FTS_ERR;
1410 __set_errno (ENAMETOOLONG);
1413 p->fts_level = level;
1414 p->fts_parent = sp->fts_cur;
1415 p->fts_pathlen = new_len;
1417 #if defined FTS_WHITEOUT && 0
1418 if (dp->d_type == DT_WHT)
1419 p->fts_flags |= FTS_ISW;
1421 /* Store dirent.d_ino, in case we need to sort
1422 entries before processing them. */
1423 p->fts_statp->st_ino = D_INO (dp);
1425 /* Build a file name for fts_stat to stat. */
1426 if (ISSET(FTS_NOCHDIR)) {
1427 p->fts_accpath = p->fts_path;
1428 memmove(cp, p->fts_name, p->fts_namelen + 1);
1430 p->fts_accpath = p->fts_name;
1432 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1433 /* Record what fts_read will have to do with this
1434 entry. In many cases, it will simply fts_stat it,
1435 but we can take advantage of any d_type information
1436 to optimize away the unnecessary stat calls. I.e.,
1437 if FTS_NOSTAT is in effect and we're not following
1438 symlinks (FTS_PHYSICAL) and d_type indicates this
1439 is *not* a directory, then we won't have to stat it
1440 at all. If it *is* a directory, then (currently)
1441 we stat it regardless, in order to get device and
1442 inode numbers. Some day we might optimize that
1443 away, too, for directories where d_ino is known to
1445 bool skip_stat = (ISSET(FTS_PHYSICAL)
1446 && ISSET(FTS_NOSTAT)
1448 && ! DT_MUST_BE(dp, DT_DIR));
1449 p->fts_info = FTS_NSOK;
1450 /* Propagate dirent.d_type information back
1451 to caller, when possible. */
1452 set_stat_type (p->fts_statp, D_TYPE (dp));
1453 fts_set_stat_required(p, !skip_stat);
1454 is_dir = (ISSET(FTS_PHYSICAL)
1455 && DT_MUST_BE(dp, DT_DIR));
1457 p->fts_info = fts_stat(sp, p, false);
1458 is_dir = (p->fts_info == FTS_D
1459 || p->fts_info == FTS_DC
1460 || p->fts_info == FTS_DOT);
1463 /* Decrement link count if applicable. */
1464 if (nlinks > 0 && is_dir)
1467 /* We walk in directory order so "ls -f" doesn't get upset. */
1481 * If realloc() changed the address of the file name, adjust the
1482 * addresses for the rest of the tree and the dir list.
1485 fts_padjust(sp, head);
1488 * If not changing directories, reset the file name back to original
1491 if (ISSET(FTS_NOCHDIR)) {
1492 if (len == sp->fts_pathlen || nitems == 0)
1498 * If descended after called from fts_children or after called from
1499 * fts_read and nothing found, get back. At the root level we use
1500 * the saved fd; if one of fts_open()'s arguments is a relative name
1501 * to an empty directory, we wind up here with no other way back. If
1502 * can't get back, we're done.
1504 if (descend && (type == BCHILD || !nitems) &&
1505 (cur->fts_level == FTS_ROOTLEVEL
1506 ? RESTORE_INITIAL_CWD(sp)
1507 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1508 cur->fts_info = FTS_ERR;
1514 /* If didn't find anything, return NULL. */
1517 cur->fts_info = FTS_DP;
1522 /* If there are many entries, no sorting function has been specified,
1523 and this file system is of a type that may be slow with a large
1524 number of entries, then sort the directory entries on increasing
1526 if (nitems > _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
1528 && ISSET (FTS_CWDFD)
1529 && dirent_inode_sort_may_be_useful (sp->fts_cwd_fd)) {
1530 sp->fts_compar = fts_compare_ino;
1531 head = fts_sort (sp, head, nitems);
1532 sp->fts_compar = NULL;
1535 /* Sort the entries. */
1536 if (sp->fts_compar && nitems > 1)
1537 head = fts_sort(sp, head, nitems);
1543 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1544 current hierarchy. There should be a directory with dev/inode
1545 matching those of AD. If not, print a lot of diagnostics. */
1547 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1550 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1552 if (ad->ino == ent->fts_statp->st_ino
1553 && ad->dev == ent->fts_statp->st_dev)
1556 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1557 printf ("active dirs:\n");
1559 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1560 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1561 ad->fts_ent->fts_accpath,
1562 (uintmax_t) ad->dev,
1563 (uintmax_t) ad->ino,
1565 (uintmax_t) ent->fts_statp->st_dev,
1566 (uintmax_t) ent->fts_statp->st_ino);
1570 fts_cross_check (FTS const *sp)
1572 FTSENT const *ent = sp->fts_cur;
1574 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1577 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1578 /* Make sure every parent dir is in the tree. */
1579 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1581 struct Active_dir ad;
1582 ad.ino = t->fts_statp->st_ino;
1583 ad.dev = t->fts_statp->st_dev;
1584 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1585 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1588 /* Make sure every dir in the tree is an active dir.
1589 But ENT is not necessarily a directory. If so, just skip this part. */
1590 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1591 && (ent->fts_info == FTS_DP
1592 || ent->fts_info == FTS_D))
1594 struct Active_dir *ad;
1595 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1596 ad = hash_get_next (sp->fts_cycle.ht, ad))
1598 find_matching_ancestor (ent, ad);
1604 same_fd (int fd1, int fd2)
1606 struct stat sb1, sb2;
1607 return (fstat (fd1, &sb1) == 0
1608 && fstat (fd2, &sb2) == 0
1609 && SAME_INODE (sb1, sb2));
1613 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1615 I_ring const *fd_ring = &sp->fts_fd_ring;
1616 unsigned int i = fd_ring->fts_front;
1617 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1618 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1620 if (i_ring_empty (fd_ring))
1625 int fd = fd_ring->fts_fd_ring[i];
1627 fprintf (stream, "%d: %d:\n", i, fd);
1630 char *wd = getcwdat (fd, NULL, 0);
1631 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1634 if (i == fd_ring->fts_back)
1636 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1640 /* Ensure that each file descriptor on the fd_ring matches a
1641 parent, grandparent, etc. of the current working directory. */
1643 fd_ring_check (FTS const *sp)
1648 /* Make a writable copy. */
1649 I_ring fd_w = sp->fts_fd_ring;
1651 int cwd_fd = sp->fts_cwd_fd;
1652 cwd_fd = dup (cwd_fd);
1653 char *dot = getcwdat (cwd_fd, NULL, 0);
1654 error (0, 0, "===== check ===== cwd: %s", dot);
1656 while ( ! i_ring_empty (&fd_w))
1658 int fd = i_ring_pop (&fd_w);
1661 int parent_fd = openat (cwd_fd, "..", O_RDONLY);
1667 if (!same_fd (fd, parent_fd))
1669 char *cwd = getcwdat (fd, NULL, 0);
1670 error (0, errno, "ring : %s", cwd);
1671 char *c2 = getcwdat (parent_fd, NULL, 0);
1672 error (0, errno, "parent: %s", c2);
1685 static unsigned short int
1687 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1689 struct stat *sbp = p->fts_statp;
1692 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1695 #if defined FTS_WHITEOUT && 0
1696 /* check for whiteout */
1697 if (p->fts_flags & FTS_ISW) {
1698 memset(sbp, '\0', sizeof (*sbp));
1699 sbp->st_mode = S_IFWHT;
1705 * If doing a logical walk, or application requested FTS_FOLLOW, do
1706 * a stat(2). If that fails, check for a non-existent symlink. If
1707 * fail, set the errno from the stat call.
1709 if (ISSET(FTS_LOGICAL) || follow) {
1710 if (stat(p->fts_accpath, sbp)) {
1711 saved_errno = errno;
1713 && lstat(p->fts_accpath, sbp) == 0) {
1715 return (FTS_SLNONE);
1717 p->fts_errno = saved_errno;
1720 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1721 AT_SYMLINK_NOFOLLOW)) {
1722 p->fts_errno = errno;
1723 err: memset(sbp, 0, sizeof(struct stat));
1727 if (S_ISDIR(sbp->st_mode)) {
1728 p->fts_n_dirs_remaining = (sbp->st_nlink
1729 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1730 if (ISDOT(p->fts_name)) {
1731 /* Command-line "." and ".." are real directories. */
1732 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1738 * Cycle detection is done by brute force when the directory
1739 * is first encountered. If the tree gets deep enough or the
1740 * number of symbolic links to directories is high enough,
1741 * something faster might be worthwhile.
1745 for (t = p->fts_parent;
1746 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1747 if (sbp->st_ino == t->fts_statp->st_ino
1748 && sbp->st_dev == t->fts_statp->st_dev)
1758 if (S_ISLNK(sbp->st_mode))
1760 if (S_ISREG(sbp->st_mode))
1762 return (FTS_DEFAULT);
1766 fts_compar (void const *a, void const *b)
1768 /* Convert A and B to the correct types, to pacify the compiler, and
1769 for portability to bizarre hosts where "void const *" and "FTSENT
1770 const **" differ in runtime representation. The comparison
1771 function cannot modify *a and *b, but there is no compile-time
1773 FTSENT const **pa = (FTSENT const **) a;
1774 FTSENT const **pb = (FTSENT const **) b;
1775 return pa[0]->fts_fts->fts_compar (pa, pb);
1780 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1782 register FTSENT **ap, *p;
1784 /* On most modern hosts, void * and FTSENT ** have the same
1785 run-time representation, and one can convert sp->fts_compar to
1786 the type qsort expects without problem. Use the heuristic that
1787 this is OK if the two pointer types are the same size, and if
1788 converting FTSENT ** to long int is the same as converting
1789 FTSENT ** to void * and then to long int. This heuristic isn't
1790 valid in general but we don't know of any counterexamples. */
1792 int (*compare) (void const *, void const *) =
1793 ((sizeof &dummy == sizeof (void *)
1794 && (long int) &dummy == (long int) (void *) &dummy)
1795 ? (int (*) (void const *, void const *)) sp->fts_compar
1799 * Construct an array of pointers to the structures and call qsort(3).
1800 * Reassemble the array in the order returned by qsort. If unable to
1801 * sort for memory reasons, return the directory entries in their
1802 * current order. Allocate enough space for the current needs plus
1803 * 40 so don't realloc one entry at a time.
1805 if (nitems > sp->fts_nitems) {
1808 sp->fts_nitems = nitems + 40;
1809 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1810 || ! (a = realloc (sp->fts_array,
1811 sp->fts_nitems * sizeof *a))) {
1812 free(sp->fts_array);
1813 sp->fts_array = NULL;
1819 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1821 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1822 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1823 ap[0]->fts_link = ap[1];
1824 ap[0]->fts_link = NULL;
1830 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1836 * The file name is a variable length array. Allocate the FTSENT
1837 * structure and the file name in one chunk.
1839 len = sizeof(FTSENT) + namelen;
1840 if ((p = malloc(len)) == NULL)
1843 /* Copy the name and guarantee NUL termination. */
1844 memmove(p->fts_name, name, namelen);
1845 p->fts_name[namelen] = '\0';
1847 p->fts_namelen = namelen;
1849 p->fts_path = sp->fts_path;
1852 p->fts_instr = FTS_NOINSTR;
1854 p->fts_pointer = NULL;
1860 fts_lfree (register FTSENT *head)
1864 /* Free a linked list of structures. */
1865 while ((p = head)) {
1866 head = head->fts_link;
1872 * Allow essentially unlimited file name lengths; find, rm, ls should
1873 * all work on any tree. Most systems will allow creation of file
1874 * names much longer than MAXPATHLEN, even though the kernel won't
1875 * resolve them. Add the size (not just what's needed) plus 256 bytes
1876 * so don't realloc the file name 2 bytes at a time.
1880 fts_palloc (FTS *sp, size_t more)
1883 size_t new_len = sp->fts_pathlen + more + 256;
1886 * See if fts_pathlen would overflow.
1888 if (new_len < sp->fts_pathlen) {
1890 sp->fts_path = NULL;
1891 __set_errno (ENAMETOOLONG);
1894 sp->fts_pathlen = new_len;
1895 p = realloc(sp->fts_path, sp->fts_pathlen);
1898 sp->fts_path = NULL;
1906 * When the file name is realloc'd, have to fix all of the pointers in
1907 * structures already returned.
1911 fts_padjust (FTS *sp, FTSENT *head)
1914 char *addr = sp->fts_path;
1916 #define ADJUST(p) do { \
1917 if ((p)->fts_accpath != (p)->fts_name) { \
1918 (p)->fts_accpath = \
1919 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1921 (p)->fts_path = addr; \
1923 /* Adjust the current set of children. */
1924 for (p = sp->fts_child; p; p = p->fts_link)
1927 /* Adjust the rest of the tree, including the current level. */
1928 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1930 p = p->fts_link ? p->fts_link : p->fts_parent;
1936 fts_maxarglen (char * const *argv)
1940 for (max = 0; *argv; ++argv)
1941 if ((len = strlen(*argv)) > max)
1947 * Change to dir specified by fd or file name without getting
1948 * tricked by someone changing the world out from underneath us.
1949 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
1950 * If FD is non-negative, expect it to be used after this function returns,
1951 * and to be closed eventually. So don't pass e.g., `dirfd(dirp)' and then
1952 * do closedir(dirp), because that would invalidate the saved FD.
1953 * Upon failure, close FD immediately and return nonzero.
1957 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
1960 bool is_dotdot = dir && STREQ (dir, "..");
1963 /* This clause handles the unusual case in which FTS_NOCHDIR
1964 is specified, along with FTS_CWDFD. In that case, there is
1965 no need to change even the virtual cwd file descriptor.
1966 However, if FD is non-negative, we do close it here. */
1967 if (ISSET (FTS_NOCHDIR))
1969 if (ISSET (FTS_CWDFD) && 0 <= fd)
1974 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
1976 /* When possible, skip the diropen and subsequent fstat+dev/ino
1977 comparison. I.e., when changing to parent directory
1978 (chdir ("..")), use a file descriptor from the ring and
1979 save the overhead of diropen+fstat, as well as avoiding
1980 failure when we lack "x" access to the virtual cwd. */
1981 if ( ! i_ring_empty (&sp->fts_fd_ring))
1984 fd_ring_print (sp, stderr, "pre-pop");
1985 parent_fd = i_ring_pop (&sp->fts_fd_ring);
1996 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
1999 /* The following dev/inode check is necessary if we're doing a
2000 `logical' traversal (through symlinks, a la chown -L), if the
2001 system lacks O_NOFOLLOW support, or if we're changing to ".."
2002 (but not via a popped file descriptor). When changing to the
2003 name "..", O_NOFOLLOW can't help. In general, when the target is
2004 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
2005 follow a symlink, so we can avoid the expense of this fstat. */
2006 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
2007 || (dir && STREQ (dir, "..")))
2010 if (fstat(newfd, &sb))
2015 if (p->fts_statp->st_dev != sb.st_dev
2016 || p->fts_statp->st_ino != sb.st_ino)
2018 __set_errno (ENOENT); /* disinformation */
2024 if (ISSET(FTS_CWDFD))
2026 cwd_advance_fd (sp, newfd, ! is_dotdot);
2030 ret = fchdir(newfd);
2036 __set_errno (oerrno);