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>
73 # include "unistd--.h"
74 # include "same-inode.h"
78 #ifndef _D_EXACT_NAMLEN
79 # define _D_EXACT_NAMLEN(dirent) strlen ((dirent)->d_name)
82 #if HAVE_STRUCT_DIRENT_D_TYPE
83 /* True if the type of the directory entry D is known. */
84 # define DT_IS_KNOWN(d) ((d)->d_type != DT_UNKNOWN)
85 /* True if the type of the directory entry D must be T. */
86 # define DT_MUST_BE(d, t) ((d)->d_type == (t))
87 # define D_TYPE(d) ((d)->d_type)
89 # define DT_IS_KNOWN(d) false
90 # define DT_MUST_BE(d, t) false
91 # define D_TYPE(d) DT_UNKNOWN
96 /* Any nonzero values will do here, so long as they're distinct.
97 Undef any existing macros out of the way. */
123 NOT_AN_INODE_NUMBER = 0
126 #ifdef D_INO_IN_DIRENT
127 # define D_INO(dp) (dp)->d_ino
129 /* Some systems don't have inodes, so fake them to avoid lots of ifdefs. */
130 # define D_INO(dp) NOT_AN_INODE_NUMBER
133 /* If there are more than this many entries in a directory,
134 and the conditions mentioned below are satisfied, then sort
135 the entries on inode number before any further processing. */
136 #ifndef FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
137 # define FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD 10000
141 _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD = FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
146 FTS_NO_STAT_REQUIRED = 1,
147 FTS_STAT_REQUIRED = 2
152 # define close __close
154 # define closedir __closedir
156 # define fchdir __fchdir
160 # define opendir __opendir
162 # define readdir __readdir
164 # undef internal_function
165 # define internal_function /* empty */
169 # define __set_errno(Val) errno = (Val)
172 #ifndef __attribute__
173 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
174 # define __attribute__(x) /* empty */
178 #ifndef ATTRIBUTE_UNUSED
179 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
182 /* If this host provides the openat function, then we can avoid
183 attempting to open "." in some initialization code below. */
185 # define HAVE_OPENAT_SUPPORT 1
187 # define HAVE_OPENAT_SUPPORT 0
191 # define fts_assert(expr) ((void) 0)
193 # define fts_assert(expr) \
202 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
203 static FTSENT *fts_build (FTS *, int) internal_function;
204 static void fts_lfree (FTSENT *) internal_function;
205 static void fts_load (FTS *, FTSENT *) internal_function;
206 static size_t fts_maxarglen (char * const *) internal_function;
207 static void fts_padjust (FTS *, FTSENT *) internal_function;
208 static bool fts_palloc (FTS *, size_t) internal_function;
209 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
210 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
211 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
215 # include "fts-cycle.c"
217 static bool enter_dir (FTS *fts, FTSENT *ent) { return true; }
218 static void leave_dir (FTS *fts, FTSENT *ent) {}
219 static bool setup_dir (FTS *fts) { return true; }
220 static void free_dir (FTS *fts) {}
224 # define MAX(a,b) ((a) > (b) ? (a) : (b))
228 # define SIZE_MAX ((size_t) -1)
232 # define O_DIRECTORY 0
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, O_RDONLY);
317 dirp = fdopendir (new_fd);
320 int saved_errno = errno;
327 /* Virtual fchdir. Advance SP's working directory file descriptor,
328 SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
329 CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory
330 open on sp->fts_cwd_fd; i.e., to move the working directory one level
334 cwd_advance_fd (FTS *sp, int fd, bool chdir_down_one)
336 int old = sp->fts_cwd_fd;
337 fts_assert (old != fd || old == AT_FDCWD);
341 /* Push "old" onto the ring.
342 If the displaced file descriptor is non-negative, close it. */
343 int prev_fd_in_slot = i_ring_push (&sp->fts_fd_ring, old);
344 fd_ring_print (sp, stderr, "post-push");
345 if (0 <= prev_fd_in_slot)
346 close (prev_fd_in_slot); /* ignore any close failure */
348 else if ( ! ISSET (FTS_NOCHDIR))
351 close (old); /* ignore any close failure */
357 /* Open the directory DIR if possible, and return a file
358 descriptor. Return -1 and set errno on failure. It doesn't matter
359 whether the file descriptor has read or write access. */
363 diropen (FTS const *sp, char const *dir)
365 int open_flags = (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
366 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0));
368 return (ISSET (FTS_CWDFD)
369 ? openat (sp->fts_cwd_fd, dir, open_flags)
370 : open (dir, open_flags));
374 fts_open (char * const *argv,
375 register int options,
376 int (*compar) (FTSENT const **, FTSENT const **))
379 register FTSENT *p, *root;
380 register size_t nitems;
381 FTSENT *parent = NULL;
382 FTSENT *tmp = NULL; /* pacify gcc */
387 if (options & ~FTS_OPTIONMASK) {
388 __set_errno (EINVAL);
391 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
392 __set_errno (EINVAL);
395 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
396 __set_errno (EINVAL);
400 /* Allocate/initialize the stream */
401 if ((sp = malloc(sizeof(FTS))) == NULL)
403 memset(sp, 0, sizeof(FTS));
404 sp->fts_compar = compar;
405 sp->fts_options = options;
407 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
408 if (ISSET(FTS_LOGICAL)) {
413 /* Initialize fts_cwd_fd. */
414 sp->fts_cwd_fd = AT_FDCWD;
415 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
417 /* While it isn't technically necessary to open "." this
418 early, doing it here saves us the trouble of ensuring
419 later (where it'd be messier) that "." can in fact
420 be opened. If not, revert to FTS_NOCHDIR mode. */
421 int fd = open (".", O_RDONLY);
424 /* Even if `.' is unreadable, don't revert to FTS_NOCHDIR mode
425 on systems like Linux+PROC_FS, where our openat emulation
426 is good enough. Note: on a system that emulates
427 openat via /proc, this technique can still fail, but
428 only in extreme conditions, e.g., when the working
429 directory cannot be saved (i.e. save_cwd fails) --
430 and that happens on Linux only when "." is unreadable
431 and the CWD would be longer than PATH_MAX.
432 FIXME: once Linux kernel openat support is well established,
433 replace the above open call and this entire if/else block
434 with the body of the if-block below. */
435 if ( openat_needs_fchdir ())
448 * Start out with 1K of file name space, and enough, in any case,
449 * to hold the user's file names.
452 # define MAXPATHLEN 1024
455 size_t maxarglen = fts_maxarglen(argv);
456 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
460 /* Allocate/initialize root's parent. */
462 if ((parent = fts_alloc(sp, "", 0)) == NULL)
464 parent->fts_level = FTS_ROOTPARENTLEVEL;
467 /* The classic fts implementation would call fts_stat with
468 a new entry for each iteration of the loop below.
469 If the comparison function is not specified or if the
470 FTS_DEFER_STAT option is in effect, don't stat any entry
471 in this loop. This is an attempt to minimize the interval
472 between the initial stat/lstat/fstatat and the point at which
473 a directory argument is first opened. This matters for any
474 directory command line argument that resides on a file system
475 without genuine i-nodes. If you specify FTS_DEFER_STAT along
476 with a comparison function, that function must not access any
477 data via the fts_statp pointer. */
478 defer_stat = (compar == NULL || ISSET(FTS_DEFER_STAT));
480 /* Allocate/initialize root(s). */
481 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
482 /* Don't allow zero-length file names. */
483 if ((len = strlen(*argv)) == 0) {
484 __set_errno (ENOENT);
488 if ((p = fts_alloc(sp, *argv, len)) == NULL)
490 p->fts_level = FTS_ROOTLEVEL;
491 p->fts_parent = parent;
492 p->fts_accpath = p->fts_name;
493 /* Even when defer_stat is true, be sure to stat the first
494 command line argument, since fts_read (at least with
495 FTS_XDEV) requires that. */
496 if (defer_stat && root != NULL) {
497 p->fts_info = FTS_NSOK;
498 fts_set_stat_required(p, true);
500 p->fts_info = fts_stat(sp, p, false);
504 * If comparison routine supplied, traverse in sorted
505 * order; otherwise traverse in the order specified.
520 if (compar && nitems > 1)
521 root = fts_sort(sp, root, nitems);
524 * Allocate a dummy pointer and make fts_read think that we've just
525 * finished the node before the root(s); set p->fts_info to FTS_INIT
526 * so that everything about the "current" node is ignored.
528 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
530 sp->fts_cur->fts_link = root;
531 sp->fts_cur->fts_info = FTS_INIT;
532 if (! setup_dir (sp))
536 * If using chdir(2), grab a file descriptor pointing to dot to ensure
537 * that we can get back here; this could be avoided for some file names,
538 * but almost certainly not worth the effort. Slashes, symbolic links,
539 * and ".." are all fairly nasty problems. Note, if we can't get the
540 * descriptor we run anyway, just more slowly.
542 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
543 && (sp->fts_rfd = diropen (sp, ".")) < 0)
546 i_ring_init (&sp->fts_fd_ring, -1);
549 mem3: fts_lfree(root);
551 mem2: free(sp->fts_path);
558 fts_load (FTS *sp, register FTSENT *p)
564 * Load the stream structure for the next traversal. Since we don't
565 * actually enter the directory until after the preorder visit, set
566 * the fts_accpath field specially so the chdir gets done to the right
567 * place and the user can access the first node. From fts_open it's
568 * known that the file name will fit.
570 len = p->fts_pathlen = p->fts_namelen;
571 memmove(sp->fts_path, p->fts_name, len + 1);
572 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
574 memmove(p->fts_name, cp, len + 1);
575 p->fts_namelen = len;
577 p->fts_accpath = p->fts_path = sp->fts_path;
583 register FTSENT *freep, *p;
587 * This still works if we haven't read anything -- the dummy structure
588 * points to the root list, so we step through to the end of the root
589 * list which has a valid parent pointer.
592 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
594 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
600 /* Free up child linked list, sort array, file name buffer. */
602 fts_lfree(sp->fts_child);
606 if (ISSET(FTS_CWDFD))
608 if (0 <= sp->fts_cwd_fd)
609 if (close (sp->fts_cwd_fd))
612 else if (!ISSET(FTS_NOCHDIR))
614 /* Return to original directory, save errno if necessary. */
615 if (fchdir(sp->fts_rfd))
618 /* If close fails, record errno only if saved_errno is zero,
619 so that we report the probably-more-meaningful fchdir errno. */
620 if (close (sp->fts_rfd))
621 if (saved_errno == 0)
625 fd_ring_clear (&sp->fts_fd_ring);
628 if (sp->fts_leaf_optimization_works_ht)
629 hash_free (sp->fts_leaf_optimization_works_ht);
634 /* Free up the stream pointer. */
637 /* Set errno and return. */
639 __set_errno (saved_errno);
646 #if defined __linux__ \
647 && HAVE_SYS_VFS_H && HAVE_FSTATFS && HAVE_STRUCT_STATFS_F_TYPE
651 /* Linux-specific constants from coreutils' src/fs.h */
652 # define S_MAGIC_TMPFS 0x1021994
653 # define S_MAGIC_NFS 0x6969
654 # define S_MAGIC_REISERFS 0x52654973
655 # define S_MAGIC_PROC 0x9FA0
657 /* Return false if it is easy to determine the file system type of
658 the directory on which DIR_FD is open, and sorting dirents on
659 inode numbers is known not to improve traversal performance with
660 that type of file system. Otherwise, return true. */
662 dirent_inode_sort_may_be_useful (int dir_fd)
664 /* Skip the sort only if we can determine efficiently
665 that skipping it is the right thing to do.
666 The cost of performing an unnecessary sort is negligible,
667 while the cost of *not* performing it can be O(N^2) with
668 a very large constant. */
669 struct statfs fs_buf;
671 /* If fstatfs fails, assume sorting would be useful. */
672 if (fstatfs (dir_fd, &fs_buf) != 0)
675 /* FIXME: what about when f_type is not an integral type?
676 deal with that if/when it's encountered. */
677 switch (fs_buf.f_type)
681 /* On a file system of any of these types, sorting
682 is unnecessary, and hence wasteful. */
690 /* Given a file descriptor DIR_FD open on a directory D,
691 return true if it is valid to apply the leaf-optimization
692 technique of counting directories in D via stat.st_nlink. */
694 leaf_optimization_applies (int dir_fd)
696 struct statfs fs_buf;
698 /* If fstatfs fails, assume we can't use the optimization. */
699 if (fstatfs (dir_fd, &fs_buf) != 0)
702 /* FIXME: do we need to detect AFS mount points? I doubt it,
703 unless fstatfs can report S_MAGIC_REISERFS for such a directory. */
705 switch (fs_buf.f_type)
707 /* List here the file system types that lack useable dirent.d_type
708 info, yet for which the optimization does apply. */
709 case S_MAGIC_REISERFS:
713 /* Explicitly listing this or any other file system type for which
714 the optimization is not applicable is not necessary, but we leave
715 it here to document the risk. Per http://bugs.debian.org/143111,
716 /proc may have bogus stat.st_nlink values. */
724 static bool dirent_inode_sort_may_be_useful (int dir_fd) { return true; }
725 static bool leaf_optimization_applies (int dir_fd) { return false; }
729 /* link-count-optimization entry:
730 map an stat.st_dev number to a boolean: leaf_optimization_works */
737 /* Use a tiny initial size. If a traversal encounters more than
738 a few devices, the cost of growing/rehashing this table will be
739 rendered negligible by the number of inodes processed. */
740 enum { LCO_HT_INITIAL_SIZE = 13 };
743 LCO_hash (void const *x, size_t table_size)
745 struct LCO_ent const *ax = x;
746 return (uintmax_t) ax->st_dev % table_size;
750 LCO_compare (void const *x, void const *y)
752 struct LCO_ent const *ax = x;
753 struct LCO_ent const *ay = y;
754 return ax->st_dev == ay->st_dev;
757 /* Ask the same question as leaf_optimization_applies, but query
758 the cache first (FTS.fts_leaf_optimization_works_ht), and if necessary,
759 update that cache. */
761 link_count_optimize_ok (FTSENT const *p)
763 FTS *sp = p->fts_fts;
764 Hash_table *h = sp->fts_leaf_optimization_works_ht;
770 /* If we're not in CWDFD mode, don't bother with this optimization,
771 since the caller is not serious about performance. */
772 if (!ISSET(FTS_CWDFD))
775 /* map st_dev to the boolean, leaf_optimization_works */
778 h = sp->fts_leaf_optimization_works_ht
779 = hash_initialize (LCO_HT_INITIAL_SIZE, NULL, LCO_hash,
784 tmp.st_dev = p->fts_statp->st_dev;
785 ent = hash_lookup (h, &tmp);
789 /* Look-up failed. Query directly and cache the result. */
790 t2 = malloc (sizeof *t2);
794 /* Is it ok to perform the optimization in the dir, FTS_CWD_FD? */
795 opt_ok = leaf_optimization_applies (sp->fts_cwd_fd);
797 t2->st_dev = p->fts_statp->st_dev;
799 ent = hash_insert (h, t2);
802 /* insertion failed */
806 fts_assert (ent == t2);
813 * Special case of "/" at the end of the file name so that slashes aren't
814 * appended which would cause file names to be written as "....//foo".
817 (p->fts_path[p->fts_pathlen - 1] == '/' \
818 ? p->fts_pathlen - 1 : p->fts_pathlen)
821 fts_read (register FTS *sp)
823 register FTSENT *p, *tmp;
824 register unsigned short int instr;
827 /* If finished or unrecoverable error, return NULL. */
828 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
831 /* Set current node pointer. */
834 /* Save and zero out user instructions. */
835 instr = p->fts_instr;
836 p->fts_instr = FTS_NOINSTR;
838 /* Any type of file may be re-visited; re-stat and re-turn. */
839 if (instr == FTS_AGAIN) {
840 p->fts_info = fts_stat(sp, p, false);
843 Dprintf (("fts_read: p=%s\n",
844 p->fts_info == FTS_INIT ? "" : p->fts_path));
847 * Following a symlink -- SLNONE test allows application to see
848 * SLNONE and recover. If indirecting through a symlink, have
849 * keep a pointer to current location. If unable to get that
850 * pointer, follow fails.
852 if (instr == FTS_FOLLOW &&
853 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
854 p->fts_info = fts_stat(sp, p, true);
855 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
856 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
857 p->fts_errno = errno;
858 p->fts_info = FTS_ERR;
860 p->fts_flags |= FTS_SYMFOLLOW;
865 /* Directory in pre-order. */
866 if (p->fts_info == FTS_D) {
867 /* If skipped or crossed mount point, do post-order visit. */
868 if (instr == FTS_SKIP ||
869 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
870 if (p->fts_flags & FTS_SYMFOLLOW)
871 (void)close(p->fts_symfd);
873 fts_lfree(sp->fts_child);
874 sp->fts_child = NULL;
876 p->fts_info = FTS_DP;
877 LEAVE_DIR (sp, p, "1");
881 /* Rebuild if only read the names and now traversing. */
882 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
884 fts_lfree(sp->fts_child);
885 sp->fts_child = NULL;
889 * Cd to the subdirectory.
891 * If have already read and now fail to chdir, whack the list
892 * to make the names come out right, and set the parent errno
893 * so the application will eventually get an error condition.
894 * Set the FTS_DONTCHDIR flag so that when we logically change
895 * directories back to the parent we don't do a chdir.
897 * If haven't read do so. If the read fails, fts_build sets
898 * FTS_STOP or the fts_info field of the node.
900 if (sp->fts_child != NULL) {
901 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
902 p->fts_errno = errno;
903 p->fts_flags |= FTS_DONTCHDIR;
904 for (p = sp->fts_child; p != NULL;
907 p->fts_parent->fts_accpath;
909 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
912 /* If fts_build's call to fts_safe_changedir failed
913 because it was not able to fchdir into a
914 subdirectory, tell the caller. */
915 if (p->fts_errno && p->fts_info != FTS_DNR)
916 p->fts_info = FTS_ERR;
917 LEAVE_DIR (sp, p, "2");
921 sp->fts_child = NULL;
925 /* Move to the next node on this level. */
927 if ((p = p->fts_link) != NULL) {
932 * If reached the top, return to the original directory (or
933 * the root of the tree), and load the file names for the next
936 if (p->fts_level == FTS_ROOTLEVEL) {
937 if (RESTORE_INITIAL_CWD(sp)) {
948 * User may have called fts_set on the node. If skipped,
949 * ignore. If followed, get a file descriptor so we can
950 * get back if necessary.
952 if (p->fts_instr == FTS_SKIP)
954 if (p->fts_instr == FTS_FOLLOW) {
955 p->fts_info = fts_stat(sp, p, true);
956 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
957 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
958 p->fts_errno = errno;
959 p->fts_info = FTS_ERR;
961 p->fts_flags |= FTS_SYMFOLLOW;
963 p->fts_instr = FTS_NOINSTR;
966 name: t = sp->fts_path + NAPPEND(p->fts_parent);
968 memmove(t, p->fts_name, p->fts_namelen + 1);
971 if (p->fts_info == FTS_NSOK)
973 if (p->fts_statp->st_size == FTS_STAT_REQUIRED)
975 FTSENT *parent = p->fts_parent;
976 if (FTS_ROOTLEVEL < p->fts_level
977 /* ->fts_n_dirs_remaining is not valid
978 for command-line-specified names. */
979 && parent->fts_n_dirs_remaining == 0
981 && ISSET(FTS_PHYSICAL)
982 && link_count_optimize_ok (parent))
984 /* nothing more needed */
988 p->fts_info = fts_stat(sp, p, false);
989 if (S_ISDIR(p->fts_statp->st_mode)
990 && p->fts_level != FTS_ROOTLEVEL
991 && parent->fts_n_dirs_remaining)
992 parent->fts_n_dirs_remaining--;
996 fts_assert (p->fts_statp->st_size == FTS_NO_STAT_REQUIRED);
999 if (p->fts_info == FTS_D)
1001 /* Now that P->fts_statp is guaranteed to be valid,
1002 if this is a command-line directory, record its
1003 device number, to be used for FTS_XDEV. */
1004 if (p->fts_level == FTS_ROOTLEVEL)
1005 sp->fts_dev = p->fts_statp->st_dev;
1006 Dprintf ((" entering: %s\n", p->fts_path));
1007 if (! enter_dir (sp, p))
1009 __set_errno (ENOMEM);
1016 /* Move up to the parent node. */
1017 p = tmp->fts_parent;
1021 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
1023 * Done; free everything up and set errno to 0 so the user
1024 * can distinguish between error and EOF.
1028 return (sp->fts_cur = NULL);
1031 fts_assert (p->fts_info != FTS_NSOK);
1033 /* NUL terminate the file name. */
1034 sp->fts_path[p->fts_pathlen] = '\0';
1037 * Return to the parent directory. If at a root node, restore
1038 * the initial working directory. If we came through a symlink,
1039 * go back through the file descriptor. Otherwise, move up
1040 * one level, via "..".
1042 if (p->fts_level == FTS_ROOTLEVEL) {
1043 if (RESTORE_INITIAL_CWD(sp)) {
1044 p->fts_errno = errno;
1047 } else if (p->fts_flags & FTS_SYMFOLLOW) {
1048 if (FCHDIR(sp, p->fts_symfd)) {
1049 int saved_errno = errno;
1050 (void)close(p->fts_symfd);
1051 __set_errno (saved_errno);
1052 p->fts_errno = errno;
1055 (void)close(p->fts_symfd);
1056 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
1057 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
1058 p->fts_errno = errno;
1061 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
1062 if (p->fts_errno == 0)
1063 LEAVE_DIR (sp, p, "3");
1064 return ISSET(FTS_STOP) ? NULL : p;
1068 * Fts_set takes the stream as an argument although it's not used in this
1069 * implementation; it would be necessary if anyone wanted to add global
1070 * semantics to fts using fts_set. An error return is allowed for similar
1075 fts_set(FTS *sp ATTRIBUTE_UNUSED, FTSENT *p, int instr)
1077 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
1078 instr != FTS_NOINSTR && instr != FTS_SKIP) {
1079 __set_errno (EINVAL);
1082 p->fts_instr = instr;
1087 fts_children (register FTS *sp, int instr)
1092 if (instr != 0 && instr != FTS_NAMEONLY) {
1093 __set_errno (EINVAL);
1097 /* Set current node pointer. */
1101 * Errno set to 0 so user can distinguish empty directory from
1106 /* Fatal errors stop here. */
1107 if (ISSET(FTS_STOP))
1110 /* Return logical hierarchy of user's arguments. */
1111 if (p->fts_info == FTS_INIT)
1112 return (p->fts_link);
1115 * If not a directory being visited in pre-order, stop here. Could
1116 * allow FTS_DNR, assuming the user has fixed the problem, but the
1117 * same effect is available with FTS_AGAIN.
1119 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
1122 /* Free up any previous child list. */
1123 if (sp->fts_child != NULL)
1124 fts_lfree(sp->fts_child);
1126 if (instr == FTS_NAMEONLY) {
1133 * If using chdir on a relative file name and called BEFORE fts_read
1134 * does its chdir to the root of a traversal, we can lose -- we need to
1135 * chdir into the subdirectory, and we don't know where the current
1136 * directory is, so we can't get back so that the upcoming chdir by
1137 * fts_read will work.
1139 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
1141 return (sp->fts_child = fts_build(sp, instr));
1143 if ((fd = diropen (sp, ".")) < 0)
1144 return (sp->fts_child = NULL);
1145 sp->fts_child = fts_build(sp, instr);
1146 if (ISSET(FTS_CWDFD))
1148 cwd_advance_fd (sp, fd, true);
1154 int saved_errno = errno;
1156 __set_errno (saved_errno);
1161 return (sp->fts_child);
1164 /* A comparison function to sort on increasing inode number.
1165 For some file system types, sorting either way makes a huge
1166 performance difference for a directory with very many entries,
1167 but sorting on increasing values is slightly better than sorting
1168 on decreasing values. The difference is in the 5% range. */
1170 fts_compare_ino (struct _ftsent const **a, struct _ftsent const **b)
1172 return (a[0]->fts_statp->st_ino < b[0]->fts_statp->st_ino ? -1
1173 : b[0]->fts_statp->st_ino < a[0]->fts_statp->st_ino ? 1 : 0);
1176 /* Map the dirent.d_type value, DTYPE, to the corresponding stat.st_mode
1177 S_IF* bit and set ST.st_mode, thus clearing all other bits in that field. */
1179 set_stat_type (struct stat *st, unsigned int dtype)
1212 * This is the tricky part -- do not casually change *anything* in here. The
1213 * idea is to build the linked list of entries that are used by fts_children
1214 * and fts_read. There are lots of special cases.
1216 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
1217 * set and it's a physical walk (so that symbolic links can't be directories),
1218 * we can do things quickly. First, if it's a 4.4BSD file system, the type
1219 * of the file is in the directory entry. Otherwise, we assume that the number
1220 * of subdirectories in a node is equal to the number of links to the parent.
1221 * The former skips all stat calls. The latter skips stat calls in any leaf
1222 * directories and for any files after the subdirectories in the directory have
1223 * been found, cutting the stat calls by about 2/3.
1227 fts_build (register FTS *sp, int type)
1229 register struct dirent *dp;
1230 register FTSENT *p, *head;
1231 register size_t nitems;
1241 size_t len, maxlen, new_len;
1244 /* Set current node pointer. */
1248 * Open the directory for reading. If this fails, we're done.
1249 * If being called from fts_read, set the fts_info field.
1251 #if defined FTS_WHITEOUT && 0
1252 if (ISSET(FTS_WHITEOUT))
1253 oflag = DTF_NODUP|DTF_REWIND;
1255 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
1257 # define __opendir2(file, flag) \
1258 ( ! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
1259 ? opendirat(sp->fts_cwd_fd, file) \
1262 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
1263 if (type == BREAD) {
1264 cur->fts_info = FTS_DNR;
1265 cur->fts_errno = errno;
1269 /* Rather than calling fts_stat for each and every entry encountered
1270 in the readdir loop (below), stat each directory only right after
1272 if (cur->fts_info == FTS_NSOK)
1273 cur->fts_info = fts_stat(sp, cur, false);
1276 * Nlinks is the number of possible entries of type directory in the
1277 * directory if we're cheating on stat calls, 0 if we're not doing
1278 * any stat calls at all, (nlink_t) -1 if we're statting everything.
1280 if (type == BNAMES) {
1282 /* Be quiet about nostat, GCC. */
1284 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
1285 nlinks = (cur->fts_statp->st_nlink
1286 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1294 * If we're going to need to stat anything or we want to descend
1295 * and stay in the directory, chdir. If this fails we keep going,
1296 * but set a flag so we don't chdir after the post-order visit.
1297 * We won't be able to stat anything, but we can still return the
1298 * names themselves. Note, that since fts_read won't be able to
1299 * chdir into the directory, it will have to return different file
1300 * names than before, i.e. "a/b" instead of "b". Since the node
1301 * has already been visited in pre-order, have to wait until the
1302 * post-order visit to return the error. There is a special case
1303 * here, if there was nothing to stat then it's not an error to
1304 * not be able to stat. This is all fairly nasty. If a program
1305 * needed sorted entries or stat information, they had better be
1306 * checking FTS_NS on the returned nodes.
1308 if (nlinks || type == BREAD) {
1309 int dir_fd = dirfd(dirp);
1310 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1311 dir_fd = dup (dir_fd);
1312 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1313 if (nlinks && type == BREAD)
1314 cur->fts_errno = errno;
1315 cur->fts_flags |= FTS_DONTCHDIR;
1318 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1327 * Figure out the max file name length that can be stored in the
1328 * current buffer -- the inner loop allocates more space as necessary.
1329 * We really wouldn't have to do the maxlen calculations here, we
1330 * could do them in fts_read before returning the name, but it's a
1331 * lot easier here since the length is part of the dirent structure.
1333 * If not changing directories set a pointer so that can just append
1334 * each new component into the file name.
1337 if (ISSET(FTS_NOCHDIR)) {
1338 cp = sp->fts_path + len;
1341 /* GCC, you're too verbose. */
1345 maxlen = sp->fts_pathlen - len;
1347 level = cur->fts_level + 1;
1349 /* Read the directory, attaching each entry to the `link' pointer. */
1351 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
1354 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1357 if ((p = fts_alloc (sp, dp->d_name,
1358 _D_EXACT_NAMLEN (dp))) == NULL)
1360 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
1361 /* include space for NUL */
1362 oldaddr = sp->fts_path;
1363 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
1365 * No more memory. Save
1366 * errno, free up the current structure and the
1367 * structures already allocated.
1369 mem1: saved_errno = errno;
1373 cur->fts_info = FTS_ERR;
1375 __set_errno (saved_errno);
1378 /* Did realloc() change the pointer? */
1379 if (oldaddr != sp->fts_path) {
1381 if (ISSET(FTS_NOCHDIR))
1382 cp = sp->fts_path + len;
1384 maxlen = sp->fts_pathlen - len;
1387 new_len = len + _D_EXACT_NAMLEN (dp);
1388 if (new_len < len) {
1390 * In the unlikely event that we would end up
1391 * with a file name longer than SIZE_MAX, free up
1392 * the current structure and the structures already
1393 * allocated, then error out with ENAMETOOLONG.
1398 cur->fts_info = FTS_ERR;
1400 __set_errno (ENAMETOOLONG);
1403 p->fts_level = level;
1404 p->fts_parent = sp->fts_cur;
1405 p->fts_pathlen = new_len;
1407 #if defined FTS_WHITEOUT && 0
1408 if (dp->d_type == DT_WHT)
1409 p->fts_flags |= FTS_ISW;
1411 /* Store dirent.d_ino, in case we need to sort
1412 entries before processing them. */
1413 p->fts_statp->st_ino = D_INO (dp);
1415 /* Build a file name for fts_stat to stat. */
1416 if (ISSET(FTS_NOCHDIR)) {
1417 p->fts_accpath = p->fts_path;
1418 memmove(cp, p->fts_name, p->fts_namelen + 1);
1420 p->fts_accpath = p->fts_name;
1422 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1423 /* Record what fts_read will have to do with this
1424 entry. In many cases, it will simply fts_stat it,
1425 but we can take advantage of any d_type information
1426 to optimize away the unnecessary stat calls. I.e.,
1427 if FTS_NOSTAT is in effect and we're not following
1428 symlinks (FTS_PHYSICAL) and d_type indicates this
1429 is *not* a directory, then we won't have to stat it
1430 at all. If it *is* a directory, then (currently)
1431 we stat it regardless, in order to get device and
1432 inode numbers. Some day we might optimize that
1433 away, too, for directories where d_ino is known to
1435 bool skip_stat = (ISSET(FTS_PHYSICAL)
1436 && ISSET(FTS_NOSTAT)
1438 && ! DT_MUST_BE(dp, DT_DIR));
1439 p->fts_info = FTS_NSOK;
1440 /* Propagate dirent.d_type information back
1441 to caller, when possible. */
1442 set_stat_type (p->fts_statp, D_TYPE (dp));
1443 fts_set_stat_required(p, !skip_stat);
1444 is_dir = (ISSET(FTS_PHYSICAL)
1445 && DT_MUST_BE(dp, DT_DIR));
1447 p->fts_info = fts_stat(sp, p, false);
1448 is_dir = (p->fts_info == FTS_D
1449 || p->fts_info == FTS_DC
1450 || p->fts_info == FTS_DOT);
1453 /* Decrement link count if applicable. */
1454 if (nlinks > 0 && is_dir)
1457 /* We walk in directory order so "ls -f" doesn't get upset. */
1471 * If realloc() changed the address of the file name, adjust the
1472 * addresses for the rest of the tree and the dir list.
1475 fts_padjust(sp, head);
1478 * If not changing directories, reset the file name back to original
1481 if (ISSET(FTS_NOCHDIR)) {
1482 if (len == sp->fts_pathlen || nitems == 0)
1488 * If descended after called from fts_children or after called from
1489 * fts_read and nothing found, get back. At the root level we use
1490 * the saved fd; if one of fts_open()'s arguments is a relative name
1491 * to an empty directory, we wind up here with no other way back. If
1492 * can't get back, we're done.
1494 if (descend && (type == BCHILD || !nitems) &&
1495 (cur->fts_level == FTS_ROOTLEVEL
1496 ? RESTORE_INITIAL_CWD(sp)
1497 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1498 cur->fts_info = FTS_ERR;
1504 /* If didn't find anything, return NULL. */
1507 cur->fts_info = FTS_DP;
1512 /* If there are many entries, no sorting function has been specified,
1513 and this file system is of a type that may be slow with a large
1514 number of entries, then sort the directory entries on increasing
1516 if (nitems > _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
1518 && ISSET (FTS_CWDFD)
1519 && dirent_inode_sort_may_be_useful (sp->fts_cwd_fd)) {
1520 sp->fts_compar = fts_compare_ino;
1521 head = fts_sort (sp, head, nitems);
1522 sp->fts_compar = NULL;
1525 /* Sort the entries. */
1526 if (sp->fts_compar && nitems > 1)
1527 head = fts_sort(sp, head, nitems);
1533 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1534 current hierarchy. There should be a directory with dev/inode
1535 matching those of AD. If not, print a lot of diagnostics. */
1537 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1540 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1542 if (ad->ino == ent->fts_statp->st_ino
1543 && ad->dev == ent->fts_statp->st_dev)
1546 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1547 printf ("active dirs:\n");
1549 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1550 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1551 ad->fts_ent->fts_accpath,
1552 (uintmax_t) ad->dev,
1553 (uintmax_t) ad->ino,
1555 (uintmax_t) ent->fts_statp->st_dev,
1556 (uintmax_t) ent->fts_statp->st_ino);
1560 fts_cross_check (FTS const *sp)
1562 FTSENT const *ent = sp->fts_cur;
1564 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1567 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1568 /* Make sure every parent dir is in the tree. */
1569 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1571 struct Active_dir ad;
1572 ad.ino = t->fts_statp->st_ino;
1573 ad.dev = t->fts_statp->st_dev;
1574 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1575 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1578 /* Make sure every dir in the tree is an active dir.
1579 But ENT is not necessarily a directory. If so, just skip this part. */
1580 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1581 && (ent->fts_info == FTS_DP
1582 || ent->fts_info == FTS_D))
1584 struct Active_dir *ad;
1585 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1586 ad = hash_get_next (sp->fts_cycle.ht, ad))
1588 find_matching_ancestor (ent, ad);
1594 same_fd (int fd1, int fd2)
1596 struct stat sb1, sb2;
1597 return (fstat (fd1, &sb1) == 0
1598 && fstat (fd2, &sb2) == 0
1599 && SAME_INODE (sb1, sb2));
1603 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1605 I_ring const *fd_ring = &sp->fts_fd_ring;
1606 unsigned int i = fd_ring->fts_front;
1607 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1608 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1610 if (i_ring_empty (fd_ring))
1615 int fd = fd_ring->fts_fd_ring[i];
1617 fprintf (stream, "%d: %d:\n", i, fd);
1620 char *wd = getcwdat (fd, NULL, 0);
1621 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1624 if (i == fd_ring->fts_back)
1626 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1630 /* Ensure that each file descriptor on the fd_ring matches a
1631 parent, grandparent, etc. of the current working directory. */
1633 fd_ring_check (FTS const *sp)
1638 /* Make a writable copy. */
1639 I_ring fd_w = sp->fts_fd_ring;
1641 int cwd_fd = sp->fts_cwd_fd;
1642 cwd_fd = dup (cwd_fd);
1643 char *dot = getcwdat (cwd_fd, NULL, 0);
1644 error (0, 0, "===== check ===== cwd: %s", dot);
1646 while ( ! i_ring_empty (&fd_w))
1648 int fd = i_ring_pop (&fd_w);
1651 int parent_fd = openat (cwd_fd, "..", O_RDONLY);
1657 if (!same_fd (fd, parent_fd))
1659 char *cwd = getcwdat (fd, NULL, 0);
1660 error (0, errno, "ring : %s", cwd);
1661 char *c2 = getcwdat (parent_fd, NULL, 0);
1662 error (0, errno, "parent: %s", c2);
1675 static unsigned short int
1677 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1679 struct stat *sbp = p->fts_statp;
1682 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1685 #if defined FTS_WHITEOUT && 0
1686 /* check for whiteout */
1687 if (p->fts_flags & FTS_ISW) {
1688 memset(sbp, '\0', sizeof (*sbp));
1689 sbp->st_mode = S_IFWHT;
1695 * If doing a logical walk, or application requested FTS_FOLLOW, do
1696 * a stat(2). If that fails, check for a non-existent symlink. If
1697 * fail, set the errno from the stat call.
1699 if (ISSET(FTS_LOGICAL) || follow) {
1700 if (stat(p->fts_accpath, sbp)) {
1701 saved_errno = errno;
1703 && lstat(p->fts_accpath, sbp) == 0) {
1705 return (FTS_SLNONE);
1707 p->fts_errno = saved_errno;
1710 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1711 AT_SYMLINK_NOFOLLOW)) {
1712 p->fts_errno = errno;
1713 err: memset(sbp, 0, sizeof(struct stat));
1717 if (S_ISDIR(sbp->st_mode)) {
1718 p->fts_n_dirs_remaining = (sbp->st_nlink
1719 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1720 if (ISDOT(p->fts_name)) {
1721 /* Command-line "." and ".." are real directories. */
1722 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1728 * Cycle detection is done by brute force when the directory
1729 * is first encountered. If the tree gets deep enough or the
1730 * number of symbolic links to directories is high enough,
1731 * something faster might be worthwhile.
1735 for (t = p->fts_parent;
1736 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1737 if (sbp->st_ino == t->fts_statp->st_ino
1738 && sbp->st_dev == t->fts_statp->st_dev)
1748 if (S_ISLNK(sbp->st_mode))
1750 if (S_ISREG(sbp->st_mode))
1752 return (FTS_DEFAULT);
1756 fts_compar (void const *a, void const *b)
1758 /* Convert A and B to the correct types, to pacify the compiler, and
1759 for portability to bizarre hosts where "void const *" and "FTSENT
1760 const **" differ in runtime representation. The comparison
1761 function cannot modify *a and *b, but there is no compile-time
1763 FTSENT const **pa = (FTSENT const **) a;
1764 FTSENT const **pb = (FTSENT const **) b;
1765 return pa[0]->fts_fts->fts_compar (pa, pb);
1770 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1772 register FTSENT **ap, *p;
1774 /* On most modern hosts, void * and FTSENT ** have the same
1775 run-time representation, and one can convert sp->fts_compar to
1776 the type qsort expects without problem. Use the heuristic that
1777 this is OK if the two pointer types are the same size, and if
1778 converting FTSENT ** to long int is the same as converting
1779 FTSENT ** to void * and then to long int. This heuristic isn't
1780 valid in general but we don't know of any counterexamples. */
1782 int (*compare) (void const *, void const *) =
1783 ((sizeof &dummy == sizeof (void *)
1784 && (long int) &dummy == (long int) (void *) &dummy)
1785 ? (int (*) (void const *, void const *)) sp->fts_compar
1789 * Construct an array of pointers to the structures and call qsort(3).
1790 * Reassemble the array in the order returned by qsort. If unable to
1791 * sort for memory reasons, return the directory entries in their
1792 * current order. Allocate enough space for the current needs plus
1793 * 40 so don't realloc one entry at a time.
1795 if (nitems > sp->fts_nitems) {
1798 sp->fts_nitems = nitems + 40;
1799 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1800 || ! (a = realloc (sp->fts_array,
1801 sp->fts_nitems * sizeof *a))) {
1802 free(sp->fts_array);
1803 sp->fts_array = NULL;
1809 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1811 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1812 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1813 ap[0]->fts_link = ap[1];
1814 ap[0]->fts_link = NULL;
1820 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1826 * The file name is a variable length array. Allocate the FTSENT
1827 * structure and the file name in one chunk.
1829 len = sizeof(FTSENT) + namelen;
1830 if ((p = malloc(len)) == NULL)
1833 /* Copy the name and guarantee NUL termination. */
1834 memmove(p->fts_name, name, namelen);
1835 p->fts_name[namelen] = '\0';
1837 p->fts_namelen = namelen;
1839 p->fts_path = sp->fts_path;
1842 p->fts_instr = FTS_NOINSTR;
1844 p->fts_pointer = NULL;
1850 fts_lfree (register FTSENT *head)
1854 /* Free a linked list of structures. */
1855 while ((p = head)) {
1856 head = head->fts_link;
1862 * Allow essentially unlimited file name lengths; find, rm, ls should
1863 * all work on any tree. Most systems will allow creation of file
1864 * names much longer than MAXPATHLEN, even though the kernel won't
1865 * resolve them. Add the size (not just what's needed) plus 256 bytes
1866 * so don't realloc the file name 2 bytes at a time.
1870 fts_palloc (FTS *sp, size_t more)
1873 size_t new_len = sp->fts_pathlen + more + 256;
1876 * See if fts_pathlen would overflow.
1878 if (new_len < sp->fts_pathlen) {
1880 sp->fts_path = NULL;
1881 __set_errno (ENAMETOOLONG);
1884 sp->fts_pathlen = new_len;
1885 p = realloc(sp->fts_path, sp->fts_pathlen);
1888 sp->fts_path = NULL;
1896 * When the file name is realloc'd, have to fix all of the pointers in
1897 * structures already returned.
1901 fts_padjust (FTS *sp, FTSENT *head)
1904 char *addr = sp->fts_path;
1906 #define ADJUST(p) do { \
1907 if ((p)->fts_accpath != (p)->fts_name) { \
1908 (p)->fts_accpath = \
1909 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1911 (p)->fts_path = addr; \
1913 /* Adjust the current set of children. */
1914 for (p = sp->fts_child; p; p = p->fts_link)
1917 /* Adjust the rest of the tree, including the current level. */
1918 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1920 p = p->fts_link ? p->fts_link : p->fts_parent;
1926 fts_maxarglen (char * const *argv)
1930 for (max = 0; *argv; ++argv)
1931 if ((len = strlen(*argv)) > max)
1937 * Change to dir specified by fd or file name without getting
1938 * tricked by someone changing the world out from underneath us.
1939 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
1940 * If FD is non-negative, expect it to be used after this function returns,
1941 * and to be closed eventually. So don't pass e.g., `dirfd(dirp)' and then
1942 * do closedir(dirp), because that would invalidate the saved FD.
1943 * Upon failure, close FD immediately and return nonzero.
1947 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
1950 bool is_dotdot = dir && STREQ (dir, "..");
1953 /* This clause handles the unusual case in which FTS_NOCHDIR
1954 is specified, along with FTS_CWDFD. In that case, there is
1955 no need to change even the virtual cwd file descriptor.
1956 However, if FD is non-negative, we do close it here. */
1957 if (ISSET (FTS_NOCHDIR))
1959 if (ISSET (FTS_CWDFD) && 0 <= fd)
1964 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
1966 /* When possible, skip the diropen and subsequent fstat+dev/ino
1967 comparison. I.e., when changing to parent directory
1968 (chdir ("..")), use a file descriptor from the ring and
1969 save the overhead of diropen+fstat, as well as avoiding
1970 failure when we lack "x" access to the virtual cwd. */
1971 if ( ! i_ring_empty (&sp->fts_fd_ring))
1974 fd_ring_print (sp, stderr, "pre-pop");
1975 parent_fd = i_ring_pop (&sp->fts_fd_ring);
1986 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
1989 /* The following dev/inode check is necessary if we're doing a
1990 `logical' traversal (through symlinks, a la chown -L), if the
1991 system lacks O_NOFOLLOW support, or if we're changing to ".."
1992 (but not via a popped file descriptor). When changing to the
1993 name "..", O_NOFOLLOW can't help. In general, when the target is
1994 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
1995 follow a symlink, so we can avoid the expense of this fstat. */
1996 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
1997 || (dir && STREQ (dir, "..")))
2000 if (fstat(newfd, &sb))
2005 if (p->fts_statp->st_dev != sb.st_dev
2006 || p->fts_statp->st_ino != sb.st_ino)
2008 __set_errno (ENOENT); /* disinformation */
2014 if (ISSET(FTS_CWDFD))
2016 cwd_advance_fd (sp, newfd, ! is_dotdot);
2020 ret = fchdir(newfd);
2026 __set_errno (oerrno);