1 /* Traverse a file hierarchy.
3 Copyright (C) 2004-2011 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 readdir __readdir
166 # undef internal_function
167 # define internal_function /* empty */
171 # define __set_errno(Val) errno = (Val)
174 /* If this host provides the openat function, then we can avoid
175 attempting to open "." in some initialization code below. */
177 # define HAVE_OPENAT_SUPPORT 1
179 # define HAVE_OPENAT_SUPPORT 0
183 # define fts_assert(expr) ((void) 0)
185 # define fts_assert(expr) \
194 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
195 static FTSENT *fts_build (FTS *, int) internal_function;
196 static void fts_lfree (FTSENT *) internal_function;
197 static void fts_load (FTS *, FTSENT *) internal_function;
198 static size_t fts_maxarglen (char * const *) internal_function;
199 static void fts_padjust (FTS *, FTSENT *) internal_function;
200 static bool fts_palloc (FTS *, size_t) internal_function;
201 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
202 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
203 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
206 #include "fts-cycle.c"
209 # define MAX(a,b) ((a) > (b) ? (a) : (b))
213 # define SIZE_MAX ((size_t) -1)
216 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
217 #define STREQ(a, b) (strcmp (a, b) == 0)
219 #define CLR(opt) (sp->fts_options &= ~(opt))
220 #define ISSET(opt) (sp->fts_options & (opt))
221 #define SET(opt) (sp->fts_options |= (opt))
223 /* FIXME: make this a function */
224 #define RESTORE_INITIAL_CWD(sp) \
225 (fd_ring_clear (&((sp)->fts_fd_ring)), \
226 FCHDIR ((sp), (ISSET (FTS_CWDFD) ? AT_FDCWD : (sp)->fts_rfd)))
228 /* FIXME: FTS_NOCHDIR is now misnamed.
229 Call it FTS_USE_FULL_RELATIVE_FILE_NAMES instead. */
230 #define FCHDIR(sp, fd) \
231 (!ISSET(FTS_NOCHDIR) && (ISSET(FTS_CWDFD) \
232 ? (cwd_advance_fd ((sp), (fd), true), 0) \
236 /* fts_build flags */
237 /* FIXME: make this an enum */
238 #define BCHILD 1 /* fts_children */
239 #define BNAMES 2 /* fts_children, names only */
240 #define BREAD 3 /* fts_read */
243 # include <inttypes.h>
246 # include "getcwdat.h"
247 bool fts_debug = false;
248 # define Dprintf(x) do { if (fts_debug) printf x; } while (false)
251 # define fd_ring_check(x)
252 # define fd_ring_print(a, b, c)
255 #define LEAVE_DIR(Fts, Ent, Tag) \
258 Dprintf ((" %s-leaving: %s\n", Tag, (Ent)->fts_path)); \
259 leave_dir (Fts, Ent); \
260 fd_ring_check (Fts); \
265 fd_ring_clear (I_ring *fd_ring)
267 while ( ! i_ring_empty (fd_ring))
269 int fd = i_ring_pop (fd_ring);
275 /* Overload the fts_statp->st_size member (otherwise unused, when
276 fts_info is FTS_NSOK) to indicate whether fts_read should stat
277 this entry or not. */
279 fts_set_stat_required (FTSENT *p, bool required)
281 fts_assert (p->fts_info == FTS_NSOK);
282 p->fts_statp->st_size = (required
284 : FTS_NO_STAT_REQUIRED);
287 /* file-descriptor-relative opendir. */
288 /* FIXME: if others need this function, move it into lib/openat.c */
291 opendirat (int fd, char const *dir, int extra_flags, int *pdir_fd)
293 int new_fd = openat (fd, dir,
294 (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
300 set_cloexec_flag (new_fd, true);
301 dirp = fdopendir (new_fd);
306 int saved_errno = errno;
313 /* Virtual fchdir. Advance SP's working directory file descriptor,
314 SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
315 CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory
316 open on sp->fts_cwd_fd; i.e., to move the working directory one level
320 cwd_advance_fd (FTS *sp, int fd, bool chdir_down_one)
322 int old = sp->fts_cwd_fd;
323 fts_assert (old != fd || old == AT_FDCWD);
327 /* Push "old" onto the ring.
328 If the displaced file descriptor is non-negative, close it. */
329 int prev_fd_in_slot = i_ring_push (&sp->fts_fd_ring, old);
330 fd_ring_print (sp, stderr, "post-push");
331 if (0 <= prev_fd_in_slot)
332 close (prev_fd_in_slot); /* ignore any close failure */
334 else if ( ! ISSET (FTS_NOCHDIR))
337 close (old); /* ignore any close failure */
343 /* Open the directory DIR if possible, and return a file
344 descriptor. Return -1 and set errno on failure. It doesn't matter
345 whether the file descriptor has read or write access. */
349 diropen (FTS const *sp, char const *dir)
351 int open_flags = (O_SEARCH | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
352 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0));
354 int fd = (ISSET (FTS_CWDFD)
355 ? openat (sp->fts_cwd_fd, dir, open_flags)
356 : open (dir, open_flags));
358 set_cloexec_flag (fd, true);
363 fts_open (char * const *argv,
364 register int options,
365 int (*compar) (FTSENT const **, FTSENT const **))
368 register FTSENT *p, *root;
369 register size_t nitems;
370 FTSENT *parent = NULL;
371 FTSENT *tmp = NULL; /* pacify gcc */
375 if (options & ~FTS_OPTIONMASK) {
376 __set_errno (EINVAL);
379 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
380 __set_errno (EINVAL);
383 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
384 __set_errno (EINVAL);
388 /* Allocate/initialize the stream */
389 if ((sp = malloc(sizeof(FTS))) == NULL)
391 memset(sp, 0, sizeof(FTS));
392 sp->fts_compar = compar;
393 sp->fts_options = options;
395 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
396 if (ISSET(FTS_LOGICAL)) {
401 /* Initialize fts_cwd_fd. */
402 sp->fts_cwd_fd = AT_FDCWD;
403 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
405 /* While it isn't technically necessary to open "." this
406 early, doing it here saves us the trouble of ensuring
407 later (where it'd be messier) that "." can in fact
408 be opened. If not, revert to FTS_NOCHDIR mode. */
409 int fd = open (".", O_SEARCH);
412 /* Even if `.' is unreadable, don't revert to FTS_NOCHDIR mode
413 on systems like Linux+PROC_FS, where our openat emulation
414 is good enough. Note: on a system that emulates
415 openat via /proc, this technique can still fail, but
416 only in extreme conditions, e.g., when the working
417 directory cannot be saved (i.e. save_cwd fails) --
418 and that happens on Linux only when "." is unreadable
419 and the CWD would be longer than PATH_MAX.
420 FIXME: once Linux kernel openat support is well established,
421 replace the above open call and this entire if/else block
422 with the body of the if-block below. */
423 if ( openat_needs_fchdir ())
436 * Start out with 1K of file name space, and enough, in any case,
437 * to hold the user's file names.
440 # define MAXPATHLEN 1024
443 size_t maxarglen = fts_maxarglen(argv);
444 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
448 /* Allocate/initialize root's parent. */
450 if ((parent = fts_alloc(sp, "", 0)) == NULL)
452 parent->fts_level = FTS_ROOTPARENTLEVEL;
455 /* The classic fts implementation would call fts_stat with
456 a new entry for each iteration of the loop below.
457 If the comparison function is not specified or if the
458 FTS_DEFER_STAT option is in effect, don't stat any entry
459 in this loop. This is an attempt to minimize the interval
460 between the initial stat/lstat/fstatat and the point at which
461 a directory argument is first opened. This matters for any
462 directory command line argument that resides on a file system
463 without genuine i-nodes. If you specify FTS_DEFER_STAT along
464 with a comparison function, that function must not access any
465 data via the fts_statp pointer. */
466 defer_stat = (compar == NULL || ISSET(FTS_DEFER_STAT));
468 /* Allocate/initialize root(s). */
469 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
470 /* *Do* allow zero-length file names. */
471 size_t len = strlen(*argv);
472 if ((p = fts_alloc(sp, *argv, len)) == NULL)
474 p->fts_level = FTS_ROOTLEVEL;
475 p->fts_parent = parent;
476 p->fts_accpath = p->fts_name;
477 /* Even when defer_stat is true, be sure to stat the first
478 command line argument, since fts_read (at least with
479 FTS_XDEV) requires that. */
480 if (defer_stat && root != NULL) {
481 p->fts_info = FTS_NSOK;
482 fts_set_stat_required(p, true);
484 p->fts_info = fts_stat(sp, p, false);
488 * If comparison routine supplied, traverse in sorted
489 * order; otherwise traverse in the order specified.
504 if (compar && nitems > 1)
505 root = fts_sort(sp, root, nitems);
508 * Allocate a dummy pointer and make fts_read think that we've just
509 * finished the node before the root(s); set p->fts_info to FTS_INIT
510 * so that everything about the "current" node is ignored.
512 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
514 sp->fts_cur->fts_link = root;
515 sp->fts_cur->fts_info = FTS_INIT;
516 if (! setup_dir (sp))
520 * If using chdir(2), grab a file descriptor pointing to dot to ensure
521 * that we can get back here; this could be avoided for some file names,
522 * but almost certainly not worth the effort. Slashes, symbolic links,
523 * and ".." are all fairly nasty problems. Note, if we can't get the
524 * descriptor we run anyway, just more slowly.
526 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
527 && (sp->fts_rfd = diropen (sp, ".")) < 0)
530 i_ring_init (&sp->fts_fd_ring, -1);
533 mem3: fts_lfree(root);
535 mem2: free(sp->fts_path);
542 fts_load (FTS *sp, register FTSENT *p)
548 * Load the stream structure for the next traversal. Since we don't
549 * actually enter the directory until after the preorder visit, set
550 * the fts_accpath field specially so the chdir gets done to the right
551 * place and the user can access the first node. From fts_open it's
552 * known that the file name will fit.
554 len = p->fts_pathlen = p->fts_namelen;
555 memmove(sp->fts_path, p->fts_name, len + 1);
556 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
558 memmove(p->fts_name, cp, len + 1);
559 p->fts_namelen = len;
561 p->fts_accpath = p->fts_path = sp->fts_path;
567 register FTSENT *freep, *p;
571 * This still works if we haven't read anything -- the dummy structure
572 * points to the root list, so we step through to the end of the root
573 * list which has a valid parent pointer.
576 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
578 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
584 /* Free up child linked list, sort array, file name buffer. */
586 fts_lfree(sp->fts_child);
590 if (ISSET(FTS_CWDFD))
592 if (0 <= sp->fts_cwd_fd)
593 if (close (sp->fts_cwd_fd))
596 else if (!ISSET(FTS_NOCHDIR))
598 /* Return to original directory, save errno if necessary. */
599 if (fchdir(sp->fts_rfd))
602 /* If close fails, record errno only if saved_errno is zero,
603 so that we report the probably-more-meaningful fchdir errno. */
604 if (close (sp->fts_rfd))
605 if (saved_errno == 0)
609 fd_ring_clear (&sp->fts_fd_ring);
611 if (sp->fts_leaf_optimization_works_ht)
612 hash_free (sp->fts_leaf_optimization_works_ht);
616 /* Free up the stream pointer. */
619 /* Set errno and return. */
621 __set_errno (saved_errno);
628 #if defined __linux__ \
629 && HAVE_SYS_VFS_H && HAVE_FSTATFS && HAVE_STRUCT_STATFS_F_TYPE
631 # include <sys/vfs.h>
633 /* Linux-specific constants from coreutils' src/fs.h */
634 # define S_MAGIC_TMPFS 0x1021994
635 # define S_MAGIC_NFS 0x6969
636 # define S_MAGIC_REISERFS 0x52654973
637 # define S_MAGIC_PROC 0x9FA0
639 /* Return false if it is easy to determine the file system type of
640 the directory on which DIR_FD is open, and sorting dirents on
641 inode numbers is known not to improve traversal performance with
642 that type of file system. Otherwise, return true. */
644 dirent_inode_sort_may_be_useful (int dir_fd)
646 /* Skip the sort only if we can determine efficiently
647 that skipping it is the right thing to do.
648 The cost of performing an unnecessary sort is negligible,
649 while the cost of *not* performing it can be O(N^2) with
650 a very large constant. */
651 struct statfs fs_buf;
653 /* If fstatfs fails, assume sorting would be useful. */
654 if (fstatfs (dir_fd, &fs_buf) != 0)
657 /* FIXME: what about when f_type is not an integral type?
658 deal with that if/when it's encountered. */
659 switch (fs_buf.f_type)
663 /* On a file system of any of these types, sorting
664 is unnecessary, and hence wasteful. */
672 /* Given a file descriptor DIR_FD open on a directory D,
673 return true if it is valid to apply the leaf-optimization
674 technique of counting directories in D via stat.st_nlink. */
676 leaf_optimization_applies (int dir_fd)
678 struct statfs fs_buf;
680 /* If fstatfs fails, assume we can't use the optimization. */
681 if (fstatfs (dir_fd, &fs_buf) != 0)
684 /* FIXME: do we need to detect AFS mount points? I doubt it,
685 unless fstatfs can report S_MAGIC_REISERFS for such a directory. */
687 switch (fs_buf.f_type)
689 /* List here the file system types that lack useable dirent.d_type
690 info, yet for which the optimization does apply. */
691 case S_MAGIC_REISERFS:
695 /* Explicitly listing this or any other file system type for which
696 the optimization is not applicable is not necessary, but we leave
697 it here to document the risk. Per http://bugs.debian.org/143111,
698 /proc may have bogus stat.st_nlink values. */
707 dirent_inode_sort_may_be_useful (int dir_fd _GL_UNUSED) { return true; }
709 leaf_optimization_applies (int dir_fd _GL_UNUSED) { return false; }
712 /* link-count-optimization entry:
713 map a stat.st_dev number to a boolean: leaf_optimization_works */
720 /* Use a tiny initial size. If a traversal encounters more than
721 a few devices, the cost of growing/rehashing this table will be
722 rendered negligible by the number of inodes processed. */
723 enum { LCO_HT_INITIAL_SIZE = 13 };
726 LCO_hash (void const *x, size_t table_size)
728 struct LCO_ent const *ax = x;
729 return (uintmax_t) ax->st_dev % table_size;
733 LCO_compare (void const *x, void const *y)
735 struct LCO_ent const *ax = x;
736 struct LCO_ent const *ay = y;
737 return ax->st_dev == ay->st_dev;
740 /* Ask the same question as leaf_optimization_applies, but query
741 the cache first (FTS.fts_leaf_optimization_works_ht), and if necessary,
742 update that cache. */
744 link_count_optimize_ok (FTSENT const *p)
746 FTS *sp = p->fts_fts;
747 Hash_table *h = sp->fts_leaf_optimization_works_ht;
753 /* If we're not in CWDFD mode, don't bother with this optimization,
754 since the caller is not serious about performance. */
755 if (!ISSET(FTS_CWDFD))
758 /* map st_dev to the boolean, leaf_optimization_works */
761 h = sp->fts_leaf_optimization_works_ht
762 = hash_initialize (LCO_HT_INITIAL_SIZE, NULL, LCO_hash,
767 tmp.st_dev = p->fts_statp->st_dev;
768 ent = hash_lookup (h, &tmp);
772 /* Look-up failed. Query directly and cache the result. */
773 t2 = malloc (sizeof *t2);
777 /* Is it ok to perform the optimization in the dir, FTS_CWD_FD? */
778 opt_ok = leaf_optimization_applies (sp->fts_cwd_fd);
780 t2->st_dev = p->fts_statp->st_dev;
782 ent = hash_insert (h, t2);
785 /* insertion failed */
789 fts_assert (ent == t2);
795 * Special case of "/" at the end of the file name so that slashes aren't
796 * appended which would cause file names to be written as "....//foo".
799 (p->fts_path[p->fts_pathlen - 1] == '/' \
800 ? p->fts_pathlen - 1 : p->fts_pathlen)
803 fts_read (register FTS *sp)
805 register FTSENT *p, *tmp;
806 register unsigned short int instr;
809 /* If finished or unrecoverable error, return NULL. */
810 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
813 /* Set current node pointer. */
816 /* Save and zero out user instructions. */
817 instr = p->fts_instr;
818 p->fts_instr = FTS_NOINSTR;
820 /* Any type of file may be re-visited; re-stat and re-turn. */
821 if (instr == FTS_AGAIN) {
822 p->fts_info = fts_stat(sp, p, false);
825 Dprintf (("fts_read: p=%s\n",
826 p->fts_info == FTS_INIT ? "" : p->fts_path));
829 * Following a symlink -- SLNONE test allows application to see
830 * SLNONE and recover. If indirecting through a symlink, have
831 * keep a pointer to current location. If unable to get that
832 * pointer, follow fails.
834 if (instr == FTS_FOLLOW &&
835 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
836 p->fts_info = fts_stat(sp, p, true);
837 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
838 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
839 p->fts_errno = errno;
840 p->fts_info = FTS_ERR;
842 p->fts_flags |= FTS_SYMFOLLOW;
847 /* Directory in pre-order. */
848 if (p->fts_info == FTS_D) {
849 /* If skipped or crossed mount point, do post-order visit. */
850 if (instr == FTS_SKIP ||
851 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
852 if (p->fts_flags & FTS_SYMFOLLOW)
853 (void)close(p->fts_symfd);
855 fts_lfree(sp->fts_child);
856 sp->fts_child = NULL;
858 p->fts_info = FTS_DP;
859 LEAVE_DIR (sp, p, "1");
863 /* Rebuild if only read the names and now traversing. */
864 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
866 fts_lfree(sp->fts_child);
867 sp->fts_child = NULL;
871 * Cd to the subdirectory.
873 * If have already read and now fail to chdir, whack the list
874 * to make the names come out right, and set the parent errno
875 * so the application will eventually get an error condition.
876 * Set the FTS_DONTCHDIR flag so that when we logically change
877 * directories back to the parent we don't do a chdir.
879 * If haven't read do so. If the read fails, fts_build sets
880 * FTS_STOP or the fts_info field of the node.
882 if (sp->fts_child != NULL) {
883 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
884 p->fts_errno = errno;
885 p->fts_flags |= FTS_DONTCHDIR;
886 for (p = sp->fts_child; p != NULL;
889 p->fts_parent->fts_accpath;
891 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
894 /* If fts_build's call to fts_safe_changedir failed
895 because it was not able to fchdir into a
896 subdirectory, tell the caller. */
897 if (p->fts_errno && p->fts_info != FTS_DNR)
898 p->fts_info = FTS_ERR;
899 LEAVE_DIR (sp, p, "2");
903 sp->fts_child = NULL;
907 /* Move to the next node on this level. */
909 if ((p = p->fts_link) != NULL) {
914 * If reached the top, return to the original directory (or
915 * the root of the tree), and load the file names for the next
918 if (p->fts_level == FTS_ROOTLEVEL) {
919 if (RESTORE_INITIAL_CWD(sp)) {
930 * User may have called fts_set on the node. If skipped,
931 * ignore. If followed, get a file descriptor so we can
932 * get back if necessary.
934 if (p->fts_instr == FTS_SKIP)
936 if (p->fts_instr == FTS_FOLLOW) {
937 p->fts_info = fts_stat(sp, p, true);
938 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
939 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
940 p->fts_errno = errno;
941 p->fts_info = FTS_ERR;
943 p->fts_flags |= FTS_SYMFOLLOW;
945 p->fts_instr = FTS_NOINSTR;
948 name: t = sp->fts_path + NAPPEND(p->fts_parent);
950 memmove(t, p->fts_name, p->fts_namelen + 1);
953 if (p->fts_info == FTS_NSOK)
955 if (p->fts_statp->st_size == FTS_STAT_REQUIRED)
957 FTSENT *parent = p->fts_parent;
958 if (FTS_ROOTLEVEL < p->fts_level
959 /* ->fts_n_dirs_remaining is not valid
960 for command-line-specified names. */
961 && parent->fts_n_dirs_remaining == 0
963 && ISSET(FTS_PHYSICAL)
964 && link_count_optimize_ok (parent))
966 /* nothing more needed */
970 p->fts_info = fts_stat(sp, p, false);
971 if (S_ISDIR(p->fts_statp->st_mode)
972 && p->fts_level != FTS_ROOTLEVEL
973 && parent->fts_n_dirs_remaining)
974 parent->fts_n_dirs_remaining--;
978 fts_assert (p->fts_statp->st_size == FTS_NO_STAT_REQUIRED);
981 if (p->fts_info == FTS_D)
983 /* Now that P->fts_statp is guaranteed to be valid,
984 if this is a command-line directory, record its
985 device number, to be used for FTS_XDEV. */
986 if (p->fts_level == FTS_ROOTLEVEL)
987 sp->fts_dev = p->fts_statp->st_dev;
988 Dprintf ((" entering: %s\n", p->fts_path));
989 if (! enter_dir (sp, p))
991 __set_errno (ENOMEM);
998 /* Move up to the parent node. */
1003 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
1005 * Done; free everything up and set errno to 0 so the user
1006 * can distinguish between error and EOF.
1010 return (sp->fts_cur = NULL);
1013 fts_assert (p->fts_info != FTS_NSOK);
1015 /* NUL terminate the file name. */
1016 sp->fts_path[p->fts_pathlen] = '\0';
1019 * Return to the parent directory. If at a root node, restore
1020 * the initial working directory. If we came through a symlink,
1021 * go back through the file descriptor. Otherwise, move up
1022 * one level, via "..".
1024 if (p->fts_level == FTS_ROOTLEVEL) {
1025 if (RESTORE_INITIAL_CWD(sp)) {
1026 p->fts_errno = errno;
1029 } else if (p->fts_flags & FTS_SYMFOLLOW) {
1030 if (FCHDIR(sp, p->fts_symfd)) {
1031 int saved_errno = errno;
1032 (void)close(p->fts_symfd);
1033 __set_errno (saved_errno);
1034 p->fts_errno = errno;
1037 (void)close(p->fts_symfd);
1038 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
1039 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
1040 p->fts_errno = errno;
1043 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
1044 if (p->fts_errno == 0)
1045 LEAVE_DIR (sp, p, "3");
1046 return ISSET(FTS_STOP) ? NULL : p;
1050 * Fts_set takes the stream as an argument although it's not used in this
1051 * implementation; it would be necessary if anyone wanted to add global
1052 * semantics to fts using fts_set. An error return is allowed for similar
1057 fts_set(FTS *sp _GL_UNUSED, FTSENT *p, int instr)
1059 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
1060 instr != FTS_NOINSTR && instr != FTS_SKIP) {
1061 __set_errno (EINVAL);
1064 p->fts_instr = instr;
1069 fts_children (register FTS *sp, int instr)
1074 if (instr != 0 && instr != FTS_NAMEONLY) {
1075 __set_errno (EINVAL);
1079 /* Set current node pointer. */
1083 * Errno set to 0 so user can distinguish empty directory from
1088 /* Fatal errors stop here. */
1089 if (ISSET(FTS_STOP))
1092 /* Return logical hierarchy of user's arguments. */
1093 if (p->fts_info == FTS_INIT)
1094 return (p->fts_link);
1097 * If not a directory being visited in pre-order, stop here. Could
1098 * allow FTS_DNR, assuming the user has fixed the problem, but the
1099 * same effect is available with FTS_AGAIN.
1101 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
1104 /* Free up any previous child list. */
1105 if (sp->fts_child != NULL)
1106 fts_lfree(sp->fts_child);
1108 if (instr == FTS_NAMEONLY) {
1115 * If using chdir on a relative file name and called BEFORE fts_read
1116 * does its chdir to the root of a traversal, we can lose -- we need to
1117 * chdir into the subdirectory, and we don't know where the current
1118 * directory is, so we can't get back so that the upcoming chdir by
1119 * fts_read will work.
1121 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
1123 return (sp->fts_child = fts_build(sp, instr));
1125 if ((fd = diropen (sp, ".")) < 0)
1126 return (sp->fts_child = NULL);
1127 sp->fts_child = fts_build(sp, instr);
1128 if (ISSET(FTS_CWDFD))
1130 cwd_advance_fd (sp, fd, true);
1136 int saved_errno = errno;
1138 __set_errno (saved_errno);
1143 return (sp->fts_child);
1146 /* A comparison function to sort on increasing inode number.
1147 For some file system types, sorting either way makes a huge
1148 performance difference for a directory with very many entries,
1149 but sorting on increasing values is slightly better than sorting
1150 on decreasing values. The difference is in the 5% range. */
1152 fts_compare_ino (struct _ftsent const **a, struct _ftsent const **b)
1154 return (a[0]->fts_statp->st_ino < b[0]->fts_statp->st_ino ? -1
1155 : b[0]->fts_statp->st_ino < a[0]->fts_statp->st_ino ? 1 : 0);
1158 /* Map the dirent.d_type value, DTYPE, to the corresponding stat.st_mode
1159 S_IF* bit and set ST.st_mode, thus clearing all other bits in that field. */
1161 set_stat_type (struct stat *st, unsigned int dtype)
1194 * This is the tricky part -- do not casually change *anything* in here. The
1195 * idea is to build the linked list of entries that are used by fts_children
1196 * and fts_read. There are lots of special cases.
1198 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
1199 * set and it's a physical walk (so that symbolic links can't be directories),
1200 * we can do things quickly. First, if it's a 4.4BSD file system, the type
1201 * of the file is in the directory entry. Otherwise, we assume that the number
1202 * of subdirectories in a node is equal to the number of links to the parent.
1203 * The former skips all stat calls. The latter skips stat calls in any leaf
1204 * directories and for any files after the subdirectories in the directory have
1205 * been found, cutting the stat calls by about 2/3.
1209 fts_build (register FTS *sp, int type)
1211 register struct dirent *dp;
1212 register FTSENT *p, *head;
1213 register size_t nitems;
1223 size_t len, maxlen, new_len;
1227 /* Set current node pointer. */
1231 * Open the directory for reading. If this fails, we're done.
1232 * If being called from fts_read, set the fts_info field.
1234 #if defined FTS_WHITEOUT && 0
1235 if (ISSET(FTS_WHITEOUT))
1236 oflag = DTF_NODUP|DTF_REWIND;
1238 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
1240 # define __opendir2(file, flag) \
1241 opendirat((! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
1242 ? sp->fts_cwd_fd : AT_FDCWD), \
1244 ((ISSET(FTS_PHYSICAL) \
1245 && ! (ISSET(FTS_COMFOLLOW) \
1246 && cur->fts_level == FTS_ROOTLEVEL)) \
1247 ? O_NOFOLLOW : 0), \
1250 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
1251 if (type == BREAD) {
1252 cur->fts_info = FTS_DNR;
1253 cur->fts_errno = errno;
1257 /* Rather than calling fts_stat for each and every entry encountered
1258 in the readdir loop (below), stat each directory only right after
1260 if (cur->fts_info == FTS_NSOK)
1261 cur->fts_info = fts_stat(sp, cur, false);
1262 else if (sp->fts_options & FTS_TIGHT_CYCLE_CHECK) {
1263 /* Now read the stat info again after opening a directory to
1264 * reveal eventual changes caused by a submount triggered by
1265 * the traversal. But do it only for utilities which use
1266 * FTS_TIGHT_CYCLE_CHECK. Therefore, only find and du
1267 * benefit/suffer from this feature for now.
1269 LEAVE_DIR (sp, cur, "4");
1270 fts_stat (sp, cur, false);
1271 if (! enter_dir (sp, cur)) {
1272 __set_errno (ENOMEM);
1278 * Nlinks is the number of possible entries of type directory in the
1279 * directory if we're cheating on stat calls, 0 if we're not doing
1280 * any stat calls at all, (nlink_t) -1 if we're statting everything.
1282 if (type == BNAMES) {
1284 /* Be quiet about nostat, GCC. */
1286 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
1287 nlinks = (cur->fts_statp->st_nlink
1288 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1296 * If we're going to need to stat anything or we want to descend
1297 * and stay in the directory, chdir. If this fails we keep going,
1298 * but set a flag so we don't chdir after the post-order visit.
1299 * We won't be able to stat anything, but we can still return the
1300 * names themselves. Note, that since fts_read won't be able to
1301 * chdir into the directory, it will have to return different file
1302 * names than before, i.e. "a/b" instead of "b". Since the node
1303 * has already been visited in pre-order, have to wait until the
1304 * post-order visit to return the error. There is a special case
1305 * here, if there was nothing to stat then it's not an error to
1306 * not be able to stat. This is all fairly nasty. If a program
1307 * needed sorted entries or stat information, they had better be
1308 * checking FTS_NS on the returned nodes.
1310 if (nlinks || type == BREAD) {
1311 if (ISSET(FTS_CWDFD))
1313 dir_fd = dup (dir_fd);
1315 set_cloexec_flag (dir_fd, true);
1317 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1318 if (nlinks && type == BREAD)
1319 cur->fts_errno = errno;
1320 cur->fts_flags |= FTS_DONTCHDIR;
1323 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1332 * Figure out the max file name length that can be stored in the
1333 * current buffer -- the inner loop allocates more space as necessary.
1334 * We really wouldn't have to do the maxlen calculations here, we
1335 * could do them in fts_read before returning the name, but it's a
1336 * lot easier here since the length is part of the dirent structure.
1338 * If not changing directories set a pointer so that can just append
1339 * each new component into the file name.
1342 if (ISSET(FTS_NOCHDIR)) {
1343 cp = sp->fts_path + len;
1346 /* GCC, you're too verbose. */
1350 maxlen = sp->fts_pathlen - len;
1352 level = cur->fts_level + 1;
1354 /* Read the directory, attaching each entry to the `link' pointer. */
1356 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
1359 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1362 if ((p = fts_alloc (sp, dp->d_name,
1363 _D_EXACT_NAMLEN (dp))) == NULL)
1365 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
1366 /* include space for NUL */
1367 oldaddr = sp->fts_path;
1368 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
1370 * No more memory. Save
1371 * errno, free up the current structure and the
1372 * structures already allocated.
1374 mem1: saved_errno = errno;
1378 cur->fts_info = FTS_ERR;
1380 __set_errno (saved_errno);
1383 /* Did realloc() change the pointer? */
1384 if (oldaddr != sp->fts_path) {
1386 if (ISSET(FTS_NOCHDIR))
1387 cp = sp->fts_path + len;
1389 maxlen = sp->fts_pathlen - len;
1392 new_len = len + _D_EXACT_NAMLEN (dp);
1393 if (new_len < len) {
1395 * In the unlikely event that we would end up
1396 * with a file name longer than SIZE_MAX, free up
1397 * the current structure and the structures already
1398 * allocated, then error out with ENAMETOOLONG.
1403 cur->fts_info = FTS_ERR;
1405 __set_errno (ENAMETOOLONG);
1408 p->fts_level = level;
1409 p->fts_parent = sp->fts_cur;
1410 p->fts_pathlen = new_len;
1412 #if defined FTS_WHITEOUT && 0
1413 if (dp->d_type == DT_WHT)
1414 p->fts_flags |= FTS_ISW;
1416 /* Store dirent.d_ino, in case we need to sort
1417 entries before processing them. */
1418 p->fts_statp->st_ino = D_INO (dp);
1420 /* Build a file name for fts_stat to stat. */
1421 if (ISSET(FTS_NOCHDIR)) {
1422 p->fts_accpath = p->fts_path;
1423 memmove(cp, p->fts_name, p->fts_namelen + 1);
1425 p->fts_accpath = p->fts_name;
1427 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1428 /* Record what fts_read will have to do with this
1429 entry. In many cases, it will simply fts_stat it,
1430 but we can take advantage of any d_type information
1431 to optimize away the unnecessary stat calls. I.e.,
1432 if FTS_NOSTAT is in effect and we're not following
1433 symlinks (FTS_PHYSICAL) and d_type indicates this
1434 is *not* a directory, then we won't have to stat it
1435 at all. If it *is* a directory, then (currently)
1436 we stat it regardless, in order to get device and
1437 inode numbers. Some day we might optimize that
1438 away, too, for directories where d_ino is known to
1440 bool skip_stat = (ISSET(FTS_PHYSICAL)
1441 && ISSET(FTS_NOSTAT)
1443 && ! DT_MUST_BE(dp, DT_DIR));
1444 p->fts_info = FTS_NSOK;
1445 /* Propagate dirent.d_type information back
1446 to caller, when possible. */
1447 set_stat_type (p->fts_statp, D_TYPE (dp));
1448 fts_set_stat_required(p, !skip_stat);
1449 is_dir = (ISSET(FTS_PHYSICAL)
1450 && DT_MUST_BE(dp, DT_DIR));
1452 p->fts_info = fts_stat(sp, p, false);
1453 is_dir = (p->fts_info == FTS_D
1454 || p->fts_info == FTS_DC
1455 || p->fts_info == FTS_DOT);
1458 /* Decrement link count if applicable. */
1459 if (nlinks > 0 && is_dir)
1462 /* We walk in directory order so "ls -f" doesn't get upset. */
1476 * If realloc() changed the address of the file name, adjust the
1477 * addresses for the rest of the tree and the dir list.
1480 fts_padjust(sp, head);
1483 * If not changing directories, reset the file name back to original
1486 if (ISSET(FTS_NOCHDIR)) {
1487 if (len == sp->fts_pathlen || nitems == 0)
1493 * If descended after called from fts_children or after called from
1494 * fts_read and nothing found, get back. At the root level we use
1495 * the saved fd; if one of fts_open()'s arguments is a relative name
1496 * to an empty directory, we wind up here with no other way back. If
1497 * can't get back, we're done.
1499 if (descend && (type == BCHILD || !nitems) &&
1500 (cur->fts_level == FTS_ROOTLEVEL
1501 ? RESTORE_INITIAL_CWD(sp)
1502 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1503 cur->fts_info = FTS_ERR;
1509 /* If didn't find anything, return NULL. */
1512 cur->fts_info = FTS_DP;
1517 /* If there are many entries, no sorting function has been specified,
1518 and this file system is of a type that may be slow with a large
1519 number of entries, then sort the directory entries on increasing
1521 if (nitems > _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
1523 && ISSET (FTS_CWDFD)
1524 && dirent_inode_sort_may_be_useful (sp->fts_cwd_fd)) {
1525 sp->fts_compar = fts_compare_ino;
1526 head = fts_sort (sp, head, nitems);
1527 sp->fts_compar = NULL;
1530 /* Sort the entries. */
1531 if (sp->fts_compar && nitems > 1)
1532 head = fts_sort(sp, head, nitems);
1538 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1539 current hierarchy. There should be a directory with dev/inode
1540 matching those of AD. If not, print a lot of diagnostics. */
1542 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1545 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1547 if (ad->ino == ent->fts_statp->st_ino
1548 && ad->dev == ent->fts_statp->st_dev)
1551 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1552 printf ("active dirs:\n");
1554 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1555 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1556 ad->fts_ent->fts_accpath,
1557 (uintmax_t) ad->dev,
1558 (uintmax_t) ad->ino,
1560 (uintmax_t) ent->fts_statp->st_dev,
1561 (uintmax_t) ent->fts_statp->st_ino);
1565 fts_cross_check (FTS const *sp)
1567 FTSENT const *ent = sp->fts_cur;
1569 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1572 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1573 /* Make sure every parent dir is in the tree. */
1574 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1576 struct Active_dir ad;
1577 ad.ino = t->fts_statp->st_ino;
1578 ad.dev = t->fts_statp->st_dev;
1579 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1580 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1583 /* Make sure every dir in the tree is an active dir.
1584 But ENT is not necessarily a directory. If so, just skip this part. */
1585 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1586 && (ent->fts_info == FTS_DP
1587 || ent->fts_info == FTS_D))
1589 struct Active_dir *ad;
1590 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1591 ad = hash_get_next (sp->fts_cycle.ht, ad))
1593 find_matching_ancestor (ent, ad);
1599 same_fd (int fd1, int fd2)
1601 struct stat sb1, sb2;
1602 return (fstat (fd1, &sb1) == 0
1603 && fstat (fd2, &sb2) == 0
1604 && SAME_INODE (sb1, sb2));
1608 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1610 I_ring const *fd_ring = &sp->fts_fd_ring;
1611 unsigned int i = fd_ring->fts_front;
1612 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1613 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1615 if (i_ring_empty (fd_ring))
1620 int fd = fd_ring->fts_fd_ring[i];
1622 fprintf (stream, "%d: %d:\n", i, fd);
1625 char *wd = getcwdat (fd, NULL, 0);
1626 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1629 if (i == fd_ring->fts_back)
1631 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1635 /* Ensure that each file descriptor on the fd_ring matches a
1636 parent, grandparent, etc. of the current working directory. */
1638 fd_ring_check (FTS const *sp)
1643 /* Make a writable copy. */
1644 I_ring fd_w = sp->fts_fd_ring;
1646 int cwd_fd = sp->fts_cwd_fd;
1647 cwd_fd = dup (cwd_fd);
1648 char *dot = getcwdat (cwd_fd, NULL, 0);
1649 error (0, 0, "===== check ===== cwd: %s", dot);
1651 while ( ! i_ring_empty (&fd_w))
1653 int fd = i_ring_pop (&fd_w);
1656 int parent_fd = openat (cwd_fd, "..", O_SEARCH);
1662 if (!same_fd (fd, parent_fd))
1664 char *cwd = getcwdat (fd, NULL, 0);
1665 error (0, errno, "ring : %s", cwd);
1666 char *c2 = getcwdat (parent_fd, NULL, 0);
1667 error (0, errno, "parent: %s", c2);
1680 static unsigned short int
1682 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1684 struct stat *sbp = p->fts_statp;
1687 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1690 #if defined FTS_WHITEOUT && 0
1691 /* check for whiteout */
1692 if (p->fts_flags & FTS_ISW) {
1693 memset(sbp, '\0', sizeof (*sbp));
1694 sbp->st_mode = S_IFWHT;
1700 * If doing a logical walk, or application requested FTS_FOLLOW, do
1701 * a stat(2). If that fails, check for a non-existent symlink. If
1702 * fail, set the errno from the stat call.
1704 if (ISSET(FTS_LOGICAL) || follow) {
1705 if (stat(p->fts_accpath, sbp)) {
1706 saved_errno = errno;
1708 && lstat(p->fts_accpath, sbp) == 0) {
1710 return (FTS_SLNONE);
1712 p->fts_errno = saved_errno;
1715 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1716 AT_SYMLINK_NOFOLLOW)) {
1717 p->fts_errno = errno;
1718 err: memset(sbp, 0, sizeof(struct stat));
1722 if (S_ISDIR(sbp->st_mode)) {
1723 p->fts_n_dirs_remaining = (sbp->st_nlink
1724 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1725 if (ISDOT(p->fts_name)) {
1726 /* Command-line "." and ".." are real directories. */
1727 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1732 if (S_ISLNK(sbp->st_mode))
1734 if (S_ISREG(sbp->st_mode))
1736 return (FTS_DEFAULT);
1740 fts_compar (void const *a, void const *b)
1742 /* Convert A and B to the correct types, to pacify the compiler, and
1743 for portability to bizarre hosts where "void const *" and "FTSENT
1744 const **" differ in runtime representation. The comparison
1745 function cannot modify *a and *b, but there is no compile-time
1747 FTSENT const **pa = (FTSENT const **) a;
1748 FTSENT const **pb = (FTSENT const **) b;
1749 return pa[0]->fts_fts->fts_compar (pa, pb);
1754 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1756 register FTSENT **ap, *p;
1758 /* On most modern hosts, void * and FTSENT ** have the same
1759 run-time representation, and one can convert sp->fts_compar to
1760 the type qsort expects without problem. Use the heuristic that
1761 this is OK if the two pointer types are the same size, and if
1762 converting FTSENT ** to long int is the same as converting
1763 FTSENT ** to void * and then to long int. This heuristic isn't
1764 valid in general but we don't know of any counterexamples. */
1766 int (*compare) (void const *, void const *) =
1767 ((sizeof &dummy == sizeof (void *)
1768 && (long int) &dummy == (long int) (void *) &dummy)
1769 ? (int (*) (void const *, void const *)) sp->fts_compar
1773 * Construct an array of pointers to the structures and call qsort(3).
1774 * Reassemble the array in the order returned by qsort. If unable to
1775 * sort for memory reasons, return the directory entries in their
1776 * current order. Allocate enough space for the current needs plus
1777 * 40 so don't realloc one entry at a time.
1779 if (nitems > sp->fts_nitems) {
1782 sp->fts_nitems = nitems + 40;
1783 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1784 || ! (a = realloc (sp->fts_array,
1785 sp->fts_nitems * sizeof *a))) {
1786 free(sp->fts_array);
1787 sp->fts_array = NULL;
1793 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1795 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1796 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1797 ap[0]->fts_link = ap[1];
1798 ap[0]->fts_link = NULL;
1804 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1810 * The file name is a variable length array. Allocate the FTSENT
1811 * structure and the file name in one chunk.
1813 len = sizeof(FTSENT) + namelen;
1814 if ((p = malloc(len)) == NULL)
1817 /* Copy the name and guarantee NUL termination. */
1818 memmove(p->fts_name, name, namelen);
1819 p->fts_name[namelen] = '\0';
1821 p->fts_namelen = namelen;
1823 p->fts_path = sp->fts_path;
1826 p->fts_instr = FTS_NOINSTR;
1828 p->fts_pointer = NULL;
1834 fts_lfree (register FTSENT *head)
1838 /* Free a linked list of structures. */
1839 while ((p = head)) {
1840 head = head->fts_link;
1846 * Allow essentially unlimited file name lengths; find, rm, ls should
1847 * all work on any tree. Most systems will allow creation of file
1848 * names much longer than MAXPATHLEN, even though the kernel won't
1849 * resolve them. Add the size (not just what's needed) plus 256 bytes
1850 * so don't realloc the file name 2 bytes at a time.
1854 fts_palloc (FTS *sp, size_t more)
1857 size_t new_len = sp->fts_pathlen + more + 256;
1860 * See if fts_pathlen would overflow.
1862 if (new_len < sp->fts_pathlen) {
1864 sp->fts_path = NULL;
1865 __set_errno (ENAMETOOLONG);
1868 sp->fts_pathlen = new_len;
1869 p = realloc(sp->fts_path, sp->fts_pathlen);
1872 sp->fts_path = NULL;
1880 * When the file name is realloc'd, have to fix all of the pointers in
1881 * structures already returned.
1885 fts_padjust (FTS *sp, FTSENT *head)
1888 char *addr = sp->fts_path;
1890 #define ADJUST(p) do { \
1891 if ((p)->fts_accpath != (p)->fts_name) { \
1892 (p)->fts_accpath = \
1893 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1895 (p)->fts_path = addr; \
1897 /* Adjust the current set of children. */
1898 for (p = sp->fts_child; p; p = p->fts_link)
1901 /* Adjust the rest of the tree, including the current level. */
1902 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1904 p = p->fts_link ? p->fts_link : p->fts_parent;
1910 fts_maxarglen (char * const *argv)
1914 for (max = 0; *argv; ++argv)
1915 if ((len = strlen(*argv)) > max)
1921 * Change to dir specified by fd or file name without getting
1922 * tricked by someone changing the world out from underneath us.
1923 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
1924 * If FD is non-negative, expect it to be used after this function returns,
1925 * and to be closed eventually. So don't pass e.g., `dirfd(dirp)' and then
1926 * do closedir(dirp), because that would invalidate the saved FD.
1927 * Upon failure, close FD immediately and return nonzero.
1931 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
1934 bool is_dotdot = dir && STREQ (dir, "..");
1937 /* This clause handles the unusual case in which FTS_NOCHDIR
1938 is specified, along with FTS_CWDFD. In that case, there is
1939 no need to change even the virtual cwd file descriptor.
1940 However, if FD is non-negative, we do close it here. */
1941 if (ISSET (FTS_NOCHDIR))
1943 if (ISSET (FTS_CWDFD) && 0 <= fd)
1948 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
1950 /* When possible, skip the diropen and subsequent fstat+dev/ino
1951 comparison. I.e., when changing to parent directory
1952 (chdir ("..")), use a file descriptor from the ring and
1953 save the overhead of diropen+fstat, as well as avoiding
1954 failure when we lack "x" access to the virtual cwd. */
1955 if ( ! i_ring_empty (&sp->fts_fd_ring))
1958 fd_ring_print (sp, stderr, "pre-pop");
1959 parent_fd = i_ring_pop (&sp->fts_fd_ring);
1970 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
1973 /* The following dev/inode check is necessary if we're doing a
1974 `logical' traversal (through symlinks, a la chown -L), if the
1975 system lacks O_NOFOLLOW support, or if we're changing to ".."
1976 (but not via a popped file descriptor). When changing to the
1977 name "..", O_NOFOLLOW can't help. In general, when the target is
1978 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
1979 follow a symlink, so we can avoid the expense of this fstat. */
1980 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
1981 || (dir && STREQ (dir, "..")))
1984 if (fstat(newfd, &sb))
1989 if (p->fts_statp->st_dev != sb.st_dev
1990 || p->fts_statp->st_ino != sb.st_ino)
1992 __set_errno (ENOENT); /* disinformation */
1998 if (ISSET(FTS_CWDFD))
2000 cwd_advance_fd (sp, newfd, ! is_dotdot);
2004 ret = fchdir(newfd);
2010 __set_errno (oerrno);