1 /* Traverse a file hierarchy.
3 Copyright (C) 2004-2016 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 GCC_LINT && !defined lint
50 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
55 #if HAVE_SYS_PARAM_H || defined _LIBC
56 # include <sys/param.h>
59 # include <include/sys/stat.h>
61 # include <sys/stat.h>
74 # include "dirent--.h"
75 # include "unistd--.h"
76 /* FIXME - use fcntl(F_DUPFD_CLOEXEC)/openat(O_CLOEXEC) once they are
79 # include "flexmember.h"
81 # include "same-inode.h"
85 #ifndef _D_EXACT_NAMLEN
86 # define _D_EXACT_NAMLEN(dirent) strlen ((dirent)->d_name)
89 #if HAVE_STRUCT_DIRENT_D_TYPE
90 /* True if the type of the directory entry D is known. */
91 # define DT_IS_KNOWN(d) ((d)->d_type != DT_UNKNOWN)
92 /* True if the type of the directory entry D must be T. */
93 # define DT_MUST_BE(d, t) ((d)->d_type == (t))
94 # define D_TYPE(d) ((d)->d_type)
96 # define DT_IS_KNOWN(d) false
97 # define DT_MUST_BE(d, t) false
98 # define D_TYPE(d) DT_UNKNOWN
101 # define DT_UNKNOWN 0
103 /* Any nonzero values will do here, so long as they're distinct.
104 Undef any existing macros out of the way. */
130 NOT_AN_INODE_NUMBER = 0
133 #ifdef D_INO_IN_DIRENT
134 # define D_INO(dp) (dp)->d_ino
136 /* Some systems don't have inodes, so fake them to avoid lots of ifdefs. */
137 # define D_INO(dp) NOT_AN_INODE_NUMBER
140 /* If possible (see max_entries, below), read no more than this many directory
141 entries at a time. Without this limit (i.e., when using non-NULL
142 fts_compar), processing a directory with 4,000,000 entries requires ~1GiB
143 of memory, and handling 64M entries would require 16GiB of memory. */
144 #ifndef FTS_MAX_READDIR_ENTRIES
145 # define FTS_MAX_READDIR_ENTRIES 100000
148 /* If there are more than this many entries in a directory,
149 and the conditions mentioned below are satisfied, then sort
150 the entries on inode number before any further processing. */
151 #ifndef FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
152 # define FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD 10000
157 _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD = FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
162 FTS_NO_STAT_REQUIRED = 1,
163 FTS_STAT_REQUIRED = 2
168 # define close __close
170 # define closedir __closedir
172 # define fchdir __fchdir
176 # define readdir __readdir
178 # undef internal_function
179 # define internal_function /* empty */
183 # define __set_errno(Val) errno = (Val)
186 /* If this host provides the openat function, then we can avoid
187 attempting to open "." in some initialization code below. */
189 # define HAVE_OPENAT_SUPPORT 1
191 # define HAVE_OPENAT_SUPPORT 0
195 # define fts_assert(expr) ((void) (0 && (expr)))
197 # define fts_assert(expr) \
206 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
207 static FTSENT *fts_build (FTS *, int) internal_function;
208 static void fts_lfree (FTSENT *) internal_function;
209 static void fts_load (FTS *, FTSENT *) internal_function;
210 static size_t fts_maxarglen (char * const *) internal_function;
211 static void fts_padjust (FTS *, FTSENT *) internal_function;
212 static bool fts_palloc (FTS *, size_t) internal_function;
213 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
214 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
215 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
218 #include "fts-cycle.c"
221 # define MAX(a,b) ((a) > (b) ? (a) : (b))
225 # define SIZE_MAX ((size_t) -1)
228 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
229 #define STREQ(a, b) (strcmp (a, b) == 0)
231 #define CLR(opt) (sp->fts_options &= ~(opt))
232 #define ISSET(opt) (sp->fts_options & (opt))
233 #define SET(opt) (sp->fts_options |= (opt))
235 /* FIXME: FTS_NOCHDIR is now misnamed.
236 Call it FTS_USE_FULL_RELATIVE_FILE_NAMES instead. */
237 #define FCHDIR(sp, fd) \
238 (!ISSET(FTS_NOCHDIR) && (ISSET(FTS_CWDFD) \
239 ? (cwd_advance_fd ((sp), (fd), true), 0) \
243 /* fts_build flags */
244 /* FIXME: make this an enum */
245 #define BCHILD 1 /* fts_children */
246 #define BNAMES 2 /* fts_children, names only */
247 #define BREAD 3 /* fts_read */
250 # include <inttypes.h>
253 # include "getcwdat.h"
254 bool fts_debug = false;
255 # define Dprintf(x) do { if (fts_debug) printf x; } while (false)
258 # define fd_ring_check(x)
259 # define fd_ring_print(a, b, c)
262 #define LEAVE_DIR(Fts, Ent, Tag) \
265 Dprintf ((" %s-leaving: %s\n", Tag, (Ent)->fts_path)); \
266 leave_dir (Fts, Ent); \
267 fd_ring_check (Fts); \
272 fd_ring_clear (I_ring *fd_ring)
274 while ( ! i_ring_empty (fd_ring))
276 int fd = i_ring_pop (fd_ring);
282 /* Overload the fts_statp->st_size member (otherwise unused, when
283 fts_info is FTS_NSOK) to indicate whether fts_read should stat
284 this entry or not. */
286 fts_set_stat_required (FTSENT *p, bool required)
288 fts_assert (p->fts_info == FTS_NSOK);
289 p->fts_statp->st_size = (required
291 : FTS_NO_STAT_REQUIRED);
294 /* file-descriptor-relative opendir. */
295 /* FIXME: if others need this function, move it into lib/openat.c */
298 opendirat (int fd, char const *dir, int extra_flags, int *pdir_fd)
300 int new_fd = openat (fd, dir,
301 (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
307 set_cloexec_flag (new_fd, true);
308 dirp = fdopendir (new_fd);
313 int saved_errno = errno;
320 /* Virtual fchdir. Advance SP's working directory file descriptor,
321 SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
322 CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory
323 open on sp->fts_cwd_fd; i.e., to move the working directory one level
327 cwd_advance_fd (FTS *sp, int fd, bool chdir_down_one)
329 int old = sp->fts_cwd_fd;
330 fts_assert (old != fd || old == AT_FDCWD);
334 /* Push "old" onto the ring.
335 If the displaced file descriptor is non-negative, close it. */
336 int prev_fd_in_slot = i_ring_push (&sp->fts_fd_ring, old);
337 fd_ring_print (sp, stderr, "post-push");
338 if (0 <= prev_fd_in_slot)
339 close (prev_fd_in_slot); /* ignore any close failure */
341 else if ( ! ISSET (FTS_NOCHDIR))
344 close (old); /* ignore any close failure */
350 /* Restore the initial, pre-traversal, "working directory".
351 In FTS_CWDFD mode, we merely call cwd_advance_fd, otherwise,
352 we may actually change the working directory.
353 Return 0 upon success. Upon failure, set errno and return nonzero. */
355 restore_initial_cwd (FTS *sp)
357 int fail = FCHDIR (sp, ISSET (FTS_CWDFD) ? AT_FDCWD : sp->fts_rfd);
358 fd_ring_clear (&(sp->fts_fd_ring));
362 /* Open the directory DIR if possible, and return a file
363 descriptor. Return -1 and set errno on failure. It doesn't matter
364 whether the file descriptor has read or write access. */
368 diropen (FTS const *sp, char const *dir)
370 int open_flags = (O_SEARCH | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
371 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0)
372 | (ISSET (FTS_NOATIME) ? O_NOATIME : 0));
374 int fd = (ISSET (FTS_CWDFD)
375 ? openat (sp->fts_cwd_fd, dir, open_flags)
376 : open (dir, open_flags));
378 set_cloexec_flag (fd, true);
383 fts_open (char * const *argv,
384 register int options,
385 int (*compar) (FTSENT const **, FTSENT const **))
388 register FTSENT *p, *root;
389 register size_t nitems;
390 FTSENT *parent = NULL;
391 FTSENT *tmp = NULL; /* pacify gcc */
395 if (options & ~FTS_OPTIONMASK) {
396 __set_errno (EINVAL);
399 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
400 __set_errno (EINVAL);
403 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
404 __set_errno (EINVAL);
408 /* Allocate/initialize the stream */
409 if ((sp = malloc(sizeof(FTS))) == NULL)
411 memset(sp, 0, sizeof(FTS));
412 sp->fts_compar = compar;
413 sp->fts_options = options;
415 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
416 if (ISSET(FTS_LOGICAL)) {
421 /* Initialize fts_cwd_fd. */
422 sp->fts_cwd_fd = AT_FDCWD;
423 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
425 /* While it isn't technically necessary to open "." this
426 early, doing it here saves us the trouble of ensuring
427 later (where it'd be messier) that "." can in fact
428 be opened. If not, revert to FTS_NOCHDIR mode. */
430 O_SEARCH | (ISSET (FTS_NOATIME) ? O_NOATIME : 0));
433 /* Even if "." is unreadable, don't revert to FTS_NOCHDIR mode
434 on systems like Linux+PROC_FS, where our openat emulation
435 is good enough. Note: on a system that emulates
436 openat via /proc, this technique can still fail, but
437 only in extreme conditions, e.g., when the working
438 directory cannot be saved (i.e. save_cwd fails) --
439 and that happens on Linux only when "." is unreadable
440 and the CWD would be longer than PATH_MAX.
441 FIXME: once Linux kernel openat support is well established,
442 replace the above open call and this entire if/else block
443 with the body of the if-block below. */
444 if ( openat_needs_fchdir ())
457 * Start out with 1K of file name space, and enough, in any case,
458 * to hold the user's file names.
461 # define MAXPATHLEN 1024
464 size_t maxarglen = fts_maxarglen(argv);
465 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
469 /* Allocate/initialize root's parent. */
471 if ((parent = fts_alloc(sp, "", 0)) == NULL)
473 parent->fts_level = FTS_ROOTPARENTLEVEL;
476 /* The classic fts implementation would call fts_stat with
477 a new entry for each iteration of the loop below.
478 If the comparison function is not specified or if the
479 FTS_DEFER_STAT option is in effect, don't stat any entry
480 in this loop. This is an attempt to minimize the interval
481 between the initial stat/lstat/fstatat and the point at which
482 a directory argument is first opened. This matters for any
483 directory command line argument that resides on a file system
484 without genuine i-nodes. If you specify FTS_DEFER_STAT along
485 with a comparison function, that function must not access any
486 data via the fts_statp pointer. */
487 defer_stat = (compar == NULL || ISSET(FTS_DEFER_STAT));
489 /* Allocate/initialize root(s). */
490 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
491 /* *Do* allow zero-length file names. */
492 size_t len = strlen(*argv);
494 if ( ! (options & FTS_VERBATIM))
496 /* If there are two or more trailing slashes, trim all but one,
497 but don't change "//" to "/", and do map "///" to "/". */
498 char const *v = *argv;
499 if (2 < len && v[len - 1] == '/')
500 while (1 < len && v[len - 2] == '/')
504 if ((p = fts_alloc(sp, *argv, len)) == NULL)
506 p->fts_level = FTS_ROOTLEVEL;
507 p->fts_parent = parent;
508 p->fts_accpath = p->fts_name;
509 /* Even when defer_stat is true, be sure to stat the first
510 command line argument, since fts_read (at least with
511 FTS_XDEV) requires that. */
512 if (defer_stat && root != NULL) {
513 p->fts_info = FTS_NSOK;
514 fts_set_stat_required(p, true);
516 p->fts_info = fts_stat(sp, p, false);
520 * If comparison routine supplied, traverse in sorted
521 * order; otherwise traverse in the order specified.
536 if (compar && nitems > 1)
537 root = fts_sort(sp, root, nitems);
540 * Allocate a dummy pointer and make fts_read think that we've just
541 * finished the node before the root(s); set p->fts_info to FTS_INIT
542 * so that everything about the "current" node is ignored.
544 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
546 sp->fts_cur->fts_link = root;
547 sp->fts_cur->fts_info = FTS_INIT;
548 if (! setup_dir (sp))
552 * If using chdir(2), grab a file descriptor pointing to dot to ensure
553 * that we can get back here; this could be avoided for some file names,
554 * but almost certainly not worth the effort. Slashes, symbolic links,
555 * and ".." are all fairly nasty problems. Note, if we can't get the
556 * descriptor we run anyway, just more slowly.
558 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
559 && (sp->fts_rfd = diropen (sp, ".")) < 0)
562 i_ring_init (&sp->fts_fd_ring, -1);
565 mem3: fts_lfree(root);
567 mem2: free(sp->fts_path);
574 fts_load (FTS *sp, register FTSENT *p)
580 * Load the stream structure for the next traversal. Since we don't
581 * actually enter the directory until after the preorder visit, set
582 * the fts_accpath field specially so the chdir gets done to the right
583 * place and the user can access the first node. From fts_open it's
584 * known that the file name will fit.
586 len = p->fts_pathlen = p->fts_namelen;
587 memmove(sp->fts_path, p->fts_name, len + 1);
588 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
590 memmove(p->fts_name, cp, len + 1);
591 p->fts_namelen = len;
593 p->fts_accpath = p->fts_path = sp->fts_path;
599 register FTSENT *freep, *p;
603 * This still works if we haven't read anything -- the dummy structure
604 * points to the root list, so we step through to the end of the root
605 * list which has a valid parent pointer.
608 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
610 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
616 /* Free up child linked list, sort array, file name buffer. */
618 fts_lfree(sp->fts_child);
622 if (ISSET(FTS_CWDFD))
624 if (0 <= sp->fts_cwd_fd)
625 if (close (sp->fts_cwd_fd))
628 else if (!ISSET(FTS_NOCHDIR))
630 /* Return to original directory, save errno if necessary. */
631 if (fchdir(sp->fts_rfd))
634 /* If close fails, record errno only if saved_errno is zero,
635 so that we report the probably-more-meaningful fchdir errno. */
636 if (close (sp->fts_rfd))
637 if (saved_errno == 0)
641 fd_ring_clear (&sp->fts_fd_ring);
643 if (sp->fts_leaf_optimization_works_ht)
644 hash_free (sp->fts_leaf_optimization_works_ht);
648 /* Free up the stream pointer. */
651 /* Set errno and return. */
653 __set_errno (saved_errno);
660 #if defined __linux__ \
661 && HAVE_SYS_VFS_H && HAVE_FSTATFS && HAVE_STRUCT_STATFS_F_TYPE
663 # include <sys/vfs.h>
665 /* Linux-specific constants from coreutils' src/fs.h */
666 # define S_MAGIC_TMPFS 0x1021994
667 # define S_MAGIC_NFS 0x6969
668 # define S_MAGIC_REISERFS 0x52654973
669 # define S_MAGIC_XFS 0x58465342
670 # define S_MAGIC_PROC 0x9FA0
672 /* Return false if it is easy to determine the file system type of
673 the directory on which DIR_FD is open, and sorting dirents on
674 inode numbers is known not to improve traversal performance with
675 that type of file system. Otherwise, return true. */
677 dirent_inode_sort_may_be_useful (int dir_fd)
679 /* Skip the sort only if we can determine efficiently
680 that skipping it is the right thing to do.
681 The cost of performing an unnecessary sort is negligible,
682 while the cost of *not* performing it can be O(N^2) with
683 a very large constant. */
684 struct statfs fs_buf;
686 /* If fstatfs fails, assume sorting would be useful. */
687 if (fstatfs (dir_fd, &fs_buf) != 0)
690 /* FIXME: what about when f_type is not an integral type?
691 deal with that if/when it's encountered. */
692 switch (fs_buf.f_type)
696 /* On a file system of any of these types, sorting
697 is unnecessary, and hence wasteful. */
705 /* Given a file descriptor DIR_FD open on a directory D,
706 return true if it is valid to apply the leaf-optimization
707 technique of counting directories in D via stat.st_nlink. */
709 leaf_optimization_applies (int dir_fd)
711 struct statfs fs_buf;
713 /* If fstatfs fails, assume we can't use the optimization. */
714 if (fstatfs (dir_fd, &fs_buf) != 0)
717 /* FIXME: do we need to detect AFS mount points? I doubt it,
718 unless fstatfs can report S_MAGIC_REISERFS for such a directory. */
720 switch (fs_buf.f_type)
722 /* List here the file system types that lack usable dirent.d_type
723 info, yet for which the optimization does apply. */
724 case S_MAGIC_REISERFS:
728 /* Explicitly list here any other file system type for which the
729 optimization is not applicable, but need documentation. */
731 /* NFS provides usable dirent.d_type but not necessarily for all entries
732 of large directories, so as per <https://bugzilla.redhat.com/1252549>
733 NFS should return true. However st_nlink values are not accurate on
734 all implementations as per <https://bugzilla.redhat.com/1299169>. */
737 /* Per <http://bugs.debian.org/143111> /proc may have
738 bogus stat.st_nlink values. */
747 dirent_inode_sort_may_be_useful (int dir_fd _GL_UNUSED) { return true; }
749 leaf_optimization_applies (int dir_fd _GL_UNUSED) { return false; }
752 /* link-count-optimization entry:
753 map a stat.st_dev number to a boolean: leaf_optimization_works */
760 /* Use a tiny initial size. If a traversal encounters more than
761 a few devices, the cost of growing/rehashing this table will be
762 rendered negligible by the number of inodes processed. */
763 enum { LCO_HT_INITIAL_SIZE = 13 };
766 LCO_hash (void const *x, size_t table_size)
768 struct LCO_ent const *ax = x;
769 return (uintmax_t) ax->st_dev % table_size;
773 LCO_compare (void const *x, void const *y)
775 struct LCO_ent const *ax = x;
776 struct LCO_ent const *ay = y;
777 return ax->st_dev == ay->st_dev;
780 /* Ask the same question as leaf_optimization_applies, but query
781 the cache first (FTS.fts_leaf_optimization_works_ht), and if necessary,
782 update that cache. */
784 link_count_optimize_ok (FTSENT const *p)
786 FTS *sp = p->fts_fts;
787 Hash_table *h = sp->fts_leaf_optimization_works_ht;
793 /* If we're not in CWDFD mode, don't bother with this optimization,
794 since the caller is not serious about performance. */
795 if (!ISSET(FTS_CWDFD))
798 /* map st_dev to the boolean, leaf_optimization_works */
801 h = sp->fts_leaf_optimization_works_ht
802 = hash_initialize (LCO_HT_INITIAL_SIZE, NULL, LCO_hash,
807 tmp.st_dev = p->fts_statp->st_dev;
808 ent = hash_lookup (h, &tmp);
812 /* Look-up failed. Query directly and cache the result. */
813 t2 = malloc (sizeof *t2);
817 /* Is it ok to perform the optimization in the dir, FTS_CWD_FD? */
818 opt_ok = leaf_optimization_applies (sp->fts_cwd_fd);
820 t2->st_dev = p->fts_statp->st_dev;
822 ent = hash_insert (h, t2);
825 /* insertion failed */
829 fts_assert (ent == t2);
835 * Special case of "/" at the end of the file name so that slashes aren't
836 * appended which would cause file names to be written as "....//foo".
839 (p->fts_path[p->fts_pathlen - 1] == '/' \
840 ? p->fts_pathlen - 1 : p->fts_pathlen)
843 fts_read (register FTS *sp)
845 register FTSENT *p, *tmp;
846 register unsigned short int instr;
849 /* If finished or unrecoverable error, return NULL. */
850 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
853 /* Set current node pointer. */
856 /* Save and zero out user instructions. */
857 instr = p->fts_instr;
858 p->fts_instr = FTS_NOINSTR;
860 /* Any type of file may be re-visited; re-stat and re-turn. */
861 if (instr == FTS_AGAIN) {
862 p->fts_info = fts_stat(sp, p, false);
865 Dprintf (("fts_read: p=%s\n",
866 p->fts_info == FTS_INIT ? "" : p->fts_path));
869 * Following a symlink -- SLNONE test allows application to see
870 * SLNONE and recover. If indirecting through a symlink, have
871 * keep a pointer to current location. If unable to get that
872 * pointer, follow fails.
874 if (instr == FTS_FOLLOW &&
875 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
876 p->fts_info = fts_stat(sp, p, true);
877 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
878 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
879 p->fts_errno = errno;
880 p->fts_info = FTS_ERR;
882 p->fts_flags |= FTS_SYMFOLLOW;
887 /* Directory in pre-order. */
888 if (p->fts_info == FTS_D) {
889 /* If skipped or crossed mount point, do post-order visit. */
890 if (instr == FTS_SKIP ||
891 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
892 if (p->fts_flags & FTS_SYMFOLLOW)
893 (void)close(p->fts_symfd);
895 fts_lfree(sp->fts_child);
896 sp->fts_child = NULL;
898 p->fts_info = FTS_DP;
899 LEAVE_DIR (sp, p, "1");
903 /* Rebuild if only read the names and now traversing. */
904 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
906 fts_lfree(sp->fts_child);
907 sp->fts_child = NULL;
911 * Cd to the subdirectory.
913 * If have already read and now fail to chdir, whack the list
914 * to make the names come out right, and set the parent errno
915 * so the application will eventually get an error condition.
916 * Set the FTS_DONTCHDIR flag so that when we logically change
917 * directories back to the parent we don't do a chdir.
919 * If haven't read do so. If the read fails, fts_build sets
920 * FTS_STOP or the fts_info field of the node.
922 if (sp->fts_child != NULL) {
923 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
924 p->fts_errno = errno;
925 p->fts_flags |= FTS_DONTCHDIR;
926 for (p = sp->fts_child; p != NULL;
929 p->fts_parent->fts_accpath;
931 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
934 /* If fts_build's call to fts_safe_changedir failed
935 because it was not able to fchdir into a
936 subdirectory, tell the caller. */
937 if (p->fts_errno && p->fts_info != FTS_DNR)
938 p->fts_info = FTS_ERR;
939 LEAVE_DIR (sp, p, "2");
943 sp->fts_child = NULL;
947 /* Move to the next node on this level. */
950 /* If we have so many directory entries that we're reading them
951 in batches, and we've reached the end of the current batch,
952 read in a new batch. */
953 if (p->fts_link == NULL && p->fts_parent->fts_dirp)
957 sp->fts_path[p->fts_pathlen] = '\0';
959 if ((p = fts_build (sp, BREAD)) == NULL)
970 if ((p = p->fts_link) != NULL) {
975 * If reached the top, return to the original directory (or
976 * the root of the tree), and load the file names for the next
979 if (p->fts_level == FTS_ROOTLEVEL) {
980 if (restore_initial_cwd(sp)) {
991 * User may have called fts_set on the node. If skipped,
992 * ignore. If followed, get a file descriptor so we can
993 * get back if necessary.
995 if (p->fts_instr == FTS_SKIP)
997 if (p->fts_instr == FTS_FOLLOW) {
998 p->fts_info = fts_stat(sp, p, true);
999 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
1000 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
1001 p->fts_errno = errno;
1002 p->fts_info = FTS_ERR;
1004 p->fts_flags |= FTS_SYMFOLLOW;
1006 p->fts_instr = FTS_NOINSTR;
1009 name: t = sp->fts_path + NAPPEND(p->fts_parent);
1011 memmove(t, p->fts_name, p->fts_namelen + 1);
1014 if (p->fts_info == FTS_NSOK)
1016 if (p->fts_statp->st_size == FTS_STAT_REQUIRED)
1018 FTSENT *parent = p->fts_parent;
1019 if (FTS_ROOTLEVEL < p->fts_level
1020 /* ->fts_n_dirs_remaining is not valid
1021 for command-line-specified names. */
1022 && parent->fts_n_dirs_remaining == 0
1023 && ISSET(FTS_NOSTAT)
1024 && ISSET(FTS_PHYSICAL)
1025 && link_count_optimize_ok (parent))
1027 /* nothing more needed */
1031 p->fts_info = fts_stat(sp, p, false);
1032 if (S_ISDIR(p->fts_statp->st_mode)
1033 && p->fts_level != FTS_ROOTLEVEL
1034 && parent->fts_n_dirs_remaining)
1035 parent->fts_n_dirs_remaining--;
1039 fts_assert (p->fts_statp->st_size == FTS_NO_STAT_REQUIRED);
1042 if (p->fts_info == FTS_D)
1044 /* Now that P->fts_statp is guaranteed to be valid,
1045 if this is a command-line directory, record its
1046 device number, to be used for FTS_XDEV. */
1047 if (p->fts_level == FTS_ROOTLEVEL)
1048 sp->fts_dev = p->fts_statp->st_dev;
1049 Dprintf ((" entering: %s\n", p->fts_path));
1050 if (! enter_dir (sp, p))
1052 __set_errno (ENOMEM);
1060 /* Move up to the parent node. */
1061 p = tmp->fts_parent;
1065 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
1067 * Done; free everything up and set errno to 0 so the user
1068 * can distinguish between error and EOF.
1072 return (sp->fts_cur = NULL);
1075 fts_assert (p->fts_info != FTS_NSOK);
1077 /* NUL terminate the file name. */
1078 sp->fts_path[p->fts_pathlen] = '\0';
1081 * Return to the parent directory. If at a root node, restore
1082 * the initial working directory. If we came through a symlink,
1083 * go back through the file descriptor. Otherwise, move up
1084 * one level, via "..".
1086 if (p->fts_level == FTS_ROOTLEVEL) {
1087 if (restore_initial_cwd(sp)) {
1088 p->fts_errno = errno;
1091 } else if (p->fts_flags & FTS_SYMFOLLOW) {
1092 if (FCHDIR(sp, p->fts_symfd)) {
1093 p->fts_errno = errno;
1096 (void)close(p->fts_symfd);
1097 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
1098 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
1099 p->fts_errno = errno;
1103 /* If the directory causes a cycle, preserve the FTS_DC flag and keep
1104 the corresponding dev/ino pair in the hash table. It is going to be
1105 removed when leaving the original directory. */
1106 if (p->fts_info != FTS_DC) {
1107 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
1108 if (p->fts_errno == 0)
1109 LEAVE_DIR (sp, p, "3");
1111 return ISSET(FTS_STOP) ? NULL : p;
1115 * Fts_set takes the stream as an argument although it's not used in this
1116 * implementation; it would be necessary if anyone wanted to add global
1117 * semantics to fts using fts_set. An error return is allowed for similar
1122 fts_set(FTS *sp _GL_UNUSED, FTSENT *p, int instr)
1124 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
1125 instr != FTS_NOINSTR && instr != FTS_SKIP) {
1126 __set_errno (EINVAL);
1129 p->fts_instr = instr;
1134 fts_children (register FTS *sp, int instr)
1139 if (instr != 0 && instr != FTS_NAMEONLY) {
1140 __set_errno (EINVAL);
1144 /* Set current node pointer. */
1148 * Errno set to 0 so user can distinguish empty directory from
1153 /* Fatal errors stop here. */
1154 if (ISSET(FTS_STOP))
1157 /* Return logical hierarchy of user's arguments. */
1158 if (p->fts_info == FTS_INIT)
1159 return (p->fts_link);
1162 * If not a directory being visited in pre-order, stop here. Could
1163 * allow FTS_DNR, assuming the user has fixed the problem, but the
1164 * same effect is available with FTS_AGAIN.
1166 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
1169 /* Free up any previous child list. */
1170 if (sp->fts_child != NULL)
1171 fts_lfree(sp->fts_child);
1173 if (instr == FTS_NAMEONLY) {
1180 * If using chdir on a relative file name and called BEFORE fts_read
1181 * does its chdir to the root of a traversal, we can lose -- we need to
1182 * chdir into the subdirectory, and we don't know where the current
1183 * directory is, so we can't get back so that the upcoming chdir by
1184 * fts_read will work.
1186 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
1188 return (sp->fts_child = fts_build(sp, instr));
1190 if ((fd = diropen (sp, ".")) < 0)
1191 return (sp->fts_child = NULL);
1192 sp->fts_child = fts_build(sp, instr);
1193 if (ISSET(FTS_CWDFD))
1195 cwd_advance_fd (sp, fd, true);
1201 int saved_errno = errno;
1203 __set_errno (saved_errno);
1208 return (sp->fts_child);
1211 /* A comparison function to sort on increasing inode number.
1212 For some file system types, sorting either way makes a huge
1213 performance difference for a directory with very many entries,
1214 but sorting on increasing values is slightly better than sorting
1215 on decreasing values. The difference is in the 5% range. */
1217 fts_compare_ino (struct _ftsent const **a, struct _ftsent const **b)
1219 return (a[0]->fts_statp->st_ino < b[0]->fts_statp->st_ino ? -1
1220 : b[0]->fts_statp->st_ino < a[0]->fts_statp->st_ino ? 1 : 0);
1223 /* Map the dirent.d_type value, DTYPE, to the corresponding stat.st_mode
1224 S_IF* bit and set ST.st_mode, thus clearing all other bits in that field. */
1226 set_stat_type (struct stat *st, unsigned int dtype)
1258 #define closedir_and_clear(dirp) \
1266 #define fts_opendir(file, Pdir_fd) \
1267 opendirat((! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
1268 ? sp->fts_cwd_fd : AT_FDCWD), \
1270 (((ISSET(FTS_PHYSICAL) \
1271 && ! (ISSET(FTS_COMFOLLOW) \
1272 && cur->fts_level == FTS_ROOTLEVEL)) \
1274 | (ISSET (FTS_NOATIME) ? O_NOATIME : 0)), \
1278 * This is the tricky part -- do not casually change *anything* in here. The
1279 * idea is to build the linked list of entries that are used by fts_children
1280 * and fts_read. There are lots of special cases.
1282 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
1283 * set and it's a physical walk (so that symbolic links can't be directories),
1284 * we can do things quickly. First, if it's a 4.4BSD file system, the type
1285 * of the file is in the directory entry. Otherwise, we assume that the number
1286 * of subdirectories in a node is equal to the number of links to the parent.
1287 * The former skips all stat calls. The latter skips stat calls in any leaf
1288 * directories and for any files after the subdirectories in the directory have
1289 * been found, cutting the stat calls by about 2/3.
1293 fts_build (register FTS *sp, int type)
1295 register FTSENT *p, *head;
1296 register size_t nitems;
1305 size_t len, maxlen, new_len;
1308 FTSENT *cur = sp->fts_cur;
1309 bool continue_readdir = !!cur->fts_dirp;
1312 /* When cur->fts_dirp is non-NULL, that means we should
1313 continue calling readdir on that existing DIR* pointer
1314 rather than opening a new one. */
1315 if (continue_readdir)
1317 DIR *dp = cur->fts_dirp;
1318 dir_fd = dirfd (dp);
1321 closedir_and_clear (cur->fts_dirp);
1324 cur->fts_info = FTS_DNR;
1325 cur->fts_errno = errno;
1332 /* Open the directory for reading. If this fails, we're done.
1333 If being called from fts_read, set the fts_info field. */
1334 if ((cur->fts_dirp = fts_opendir(cur->fts_accpath, &dir_fd)) == NULL)
1338 cur->fts_info = FTS_DNR;
1339 cur->fts_errno = errno;
1343 /* Rather than calling fts_stat for each and every entry encountered
1344 in the readdir loop (below), stat each directory only right after
1346 if (cur->fts_info == FTS_NSOK)
1347 cur->fts_info = fts_stat(sp, cur, false);
1348 else if (sp->fts_options & FTS_TIGHT_CYCLE_CHECK)
1350 /* Now read the stat info again after opening a directory to
1351 reveal eventual changes caused by a submount triggered by
1352 the traversal. But do it only for utilities which use
1353 FTS_TIGHT_CYCLE_CHECK. Therefore, only find and du
1354 benefit/suffer from this feature for now. */
1355 LEAVE_DIR (sp, cur, "4");
1356 fts_stat (sp, cur, false);
1357 if (! enter_dir (sp, cur))
1359 __set_errno (ENOMEM);
1365 /* Maximum number of readdir entries to read at one time. This
1366 limitation is to avoid reading millions of entries into memory
1367 at once. When an fts_compar function is specified, we have no
1368 choice: we must read all entries into memory before calling that
1369 function. But when no such function is specified, we can read
1370 entries in batches that are large enough to help us with inode-
1371 sorting, yet not so large that we risk exhausting memory. */
1372 max_entries = sp->fts_compar ? SIZE_MAX : FTS_MAX_READDIR_ENTRIES;
1375 * Nlinks is the number of possible entries of type directory in the
1376 * directory if we're cheating on stat calls, 0 if we're not doing
1377 * any stat calls at all, (nlink_t) -1 if we're statting everything.
1379 if (type == BNAMES) {
1381 /* Be quiet about nostat, GCC. */
1383 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
1384 nlinks = (cur->fts_statp->st_nlink
1385 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1393 * If we're going to need to stat anything or we want to descend
1394 * and stay in the directory, chdir. If this fails we keep going,
1395 * but set a flag so we don't chdir after the post-order visit.
1396 * We won't be able to stat anything, but we can still return the
1397 * names themselves. Note, that since fts_read won't be able to
1398 * chdir into the directory, it will have to return different file
1399 * names than before, i.e. "a/b" instead of "b". Since the node
1400 * has already been visited in pre-order, have to wait until the
1401 * post-order visit to return the error. There is a special case
1402 * here, if there was nothing to stat then it's not an error to
1403 * not be able to stat. This is all fairly nasty. If a program
1404 * needed sorted entries or stat information, they had better be
1405 * checking FTS_NS on the returned nodes.
1407 if (continue_readdir)
1409 /* When resuming a short readdir run, we already have
1410 the required dirp and dir_fd. */
1413 else if (nlinks || type == BREAD) {
1414 if (ISSET(FTS_CWDFD))
1416 dir_fd = dup (dir_fd);
1418 set_cloexec_flag (dir_fd, true);
1420 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1421 if (nlinks && type == BREAD)
1422 cur->fts_errno = errno;
1423 cur->fts_flags |= FTS_DONTCHDIR;
1425 closedir_and_clear(cur->fts_dirp);
1426 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1428 cur->fts_dirp = NULL;
1435 * Figure out the max file name length that can be stored in the
1436 * current buffer -- the inner loop allocates more space as necessary.
1437 * We really wouldn't have to do the maxlen calculations here, we
1438 * could do them in fts_read before returning the name, but it's a
1439 * lot easier here since the length is part of the dirent structure.
1441 * If not changing directories set a pointer so that can just append
1442 * each new component into the file name.
1445 if (ISSET(FTS_NOCHDIR)) {
1446 cp = sp->fts_path + len;
1449 /* GCC, you're too verbose. */
1453 maxlen = sp->fts_pathlen - len;
1455 level = cur->fts_level + 1;
1457 /* Read the directory, attaching each entry to the "link" pointer. */
1462 while (cur->fts_dirp) {
1466 struct dirent *dp = readdir(cur->fts_dirp);
1469 cur->fts_errno = errno;
1470 /* If we've not read any items yet, treat
1471 the error as if we can't access the dir. */
1472 cur->fts_info = (continue_readdir || nitems)
1473 ? FTS_ERR : FTS_DNR;
1477 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1480 d_namelen = _D_EXACT_NAMLEN (dp);
1481 p = fts_alloc (sp, dp->d_name, d_namelen);
1484 if (d_namelen >= maxlen) {
1485 /* include space for NUL */
1486 oldaddr = sp->fts_path;
1487 if (! fts_palloc(sp, d_namelen + len + 1)) {
1489 * No more memory. Save
1490 * errno, free up the current structure and the
1491 * structures already allocated.
1493 mem1: saved_errno = errno;
1496 closedir_and_clear(cur->fts_dirp);
1497 cur->fts_info = FTS_ERR;
1499 __set_errno (saved_errno);
1502 /* Did realloc() change the pointer? */
1503 if (oldaddr != sp->fts_path) {
1505 if (ISSET(FTS_NOCHDIR))
1506 cp = sp->fts_path + len;
1508 maxlen = sp->fts_pathlen - len;
1511 new_len = len + d_namelen;
1512 if (new_len < len) {
1514 * In the unlikely event that we would end up
1515 * with a file name longer than SIZE_MAX, free up
1516 * the current structure and the structures already
1517 * allocated, then error out with ENAMETOOLONG.
1521 closedir_and_clear(cur->fts_dirp);
1522 cur->fts_info = FTS_ERR;
1524 __set_errno (ENAMETOOLONG);
1527 p->fts_level = level;
1528 p->fts_parent = sp->fts_cur;
1529 p->fts_pathlen = new_len;
1531 /* Store dirent.d_ino, in case we need to sort
1532 entries before processing them. */
1533 p->fts_statp->st_ino = D_INO (dp);
1535 /* Build a file name for fts_stat to stat. */
1536 if (ISSET(FTS_NOCHDIR)) {
1537 p->fts_accpath = p->fts_path;
1538 memmove(cp, p->fts_name, p->fts_namelen + 1);
1540 p->fts_accpath = p->fts_name;
1542 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1543 /* Record what fts_read will have to do with this
1544 entry. In many cases, it will simply fts_stat it,
1545 but we can take advantage of any d_type information
1546 to optimize away the unnecessary stat calls. I.e.,
1547 if FTS_NOSTAT is in effect and we're not following
1548 symlinks (FTS_PHYSICAL) and d_type indicates this
1549 is *not* a directory, then we won't have to stat it
1550 at all. If it *is* a directory, then (currently)
1551 we stat it regardless, in order to get device and
1552 inode numbers. Some day we might optimize that
1553 away, too, for directories where d_ino is known to
1555 bool skip_stat = (ISSET(FTS_PHYSICAL)
1556 && ISSET(FTS_NOSTAT)
1558 && ! DT_MUST_BE(dp, DT_DIR));
1559 p->fts_info = FTS_NSOK;
1560 /* Propagate dirent.d_type information back
1561 to caller, when possible. */
1562 set_stat_type (p->fts_statp, D_TYPE (dp));
1563 fts_set_stat_required(p, !skip_stat);
1564 is_dir = (ISSET(FTS_PHYSICAL)
1565 && DT_MUST_BE(dp, DT_DIR));
1567 p->fts_info = fts_stat(sp, p, false);
1568 is_dir = (p->fts_info == FTS_D
1569 || p->fts_info == FTS_DC
1570 || p->fts_info == FTS_DOT);
1573 /* Decrement link count if applicable. */
1574 if (nlinks > 0 && is_dir)
1577 /* We walk in directory order so "ls -f" doesn't get upset. */
1586 if (max_entries <= nitems) {
1587 /* When there are too many dir entries, leave
1588 fts_dirp open, so that a subsequent fts_read
1589 can take up where we leave off. */
1590 goto break_without_closedir;
1595 closedir_and_clear(cur->fts_dirp);
1597 break_without_closedir:
1600 * If realloc() changed the address of the file name, adjust the
1601 * addresses for the rest of the tree and the dir list.
1604 fts_padjust(sp, head);
1607 * If not changing directories, reset the file name back to original
1610 if (ISSET(FTS_NOCHDIR)) {
1611 if (len == sp->fts_pathlen || nitems == 0)
1617 * If descended after called from fts_children or after called from
1618 * fts_read and nothing found, get back. At the root level we use
1619 * the saved fd; if one of fts_open()'s arguments is a relative name
1620 * to an empty directory, we wind up here with no other way back. If
1621 * can't get back, we're done.
1623 if (!continue_readdir && descend && (type == BCHILD || !nitems) &&
1624 (cur->fts_level == FTS_ROOTLEVEL
1625 ? restore_initial_cwd(sp)
1626 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1627 cur->fts_info = FTS_ERR;
1633 /* If didn't find anything, return NULL. */
1636 && cur->fts_info != FTS_DNR && cur->fts_info != FTS_ERR)
1637 cur->fts_info = FTS_DP;
1642 /* If there are many entries, no sorting function has been specified,
1643 and this file system is of a type that may be slow with a large
1644 number of entries, then sort the directory entries on increasing
1646 if (nitems > _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
1648 && ISSET (FTS_CWDFD)
1649 && dirent_inode_sort_may_be_useful (sp->fts_cwd_fd)) {
1650 sp->fts_compar = fts_compare_ino;
1651 head = fts_sort (sp, head, nitems);
1652 sp->fts_compar = NULL;
1655 /* Sort the entries. */
1656 if (sp->fts_compar && nitems > 1)
1657 head = fts_sort(sp, head, nitems);
1663 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1664 current hierarchy. There should be a directory with dev/inode
1665 matching those of AD. If not, print a lot of diagnostics. */
1667 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1670 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1672 if (ad->ino == ent->fts_statp->st_ino
1673 && ad->dev == ent->fts_statp->st_dev)
1676 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1677 printf ("active dirs:\n");
1679 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1680 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1681 ad->fts_ent->fts_accpath,
1682 (uintmax_t) ad->dev,
1683 (uintmax_t) ad->ino,
1685 (uintmax_t) ent->fts_statp->st_dev,
1686 (uintmax_t) ent->fts_statp->st_ino);
1690 fts_cross_check (FTS const *sp)
1692 FTSENT const *ent = sp->fts_cur;
1694 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1697 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1698 /* Make sure every parent dir is in the tree. */
1699 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1701 struct Active_dir ad;
1702 ad.ino = t->fts_statp->st_ino;
1703 ad.dev = t->fts_statp->st_dev;
1704 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1705 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1708 /* Make sure every dir in the tree is an active dir.
1709 But ENT is not necessarily a directory. If so, just skip this part. */
1710 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1711 && (ent->fts_info == FTS_DP
1712 || ent->fts_info == FTS_D))
1714 struct Active_dir *ad;
1715 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1716 ad = hash_get_next (sp->fts_cycle.ht, ad))
1718 find_matching_ancestor (ent, ad);
1724 same_fd (int fd1, int fd2)
1726 struct stat sb1, sb2;
1727 return (fstat (fd1, &sb1) == 0
1728 && fstat (fd2, &sb2) == 0
1729 && SAME_INODE (sb1, sb2));
1733 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1735 I_ring const *fd_ring = &sp->fts_fd_ring;
1736 unsigned int i = fd_ring->fts_front;
1737 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1738 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1740 if (i_ring_empty (fd_ring))
1745 int fd = fd_ring->fts_fd_ring[i];
1747 fprintf (stream, "%d: %d:\n", i, fd);
1750 char *wd = getcwdat (fd, NULL, 0);
1751 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1754 if (i == fd_ring->fts_back)
1756 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1760 /* Ensure that each file descriptor on the fd_ring matches a
1761 parent, grandparent, etc. of the current working directory. */
1763 fd_ring_check (FTS const *sp)
1768 /* Make a writable copy. */
1769 I_ring fd_w = sp->fts_fd_ring;
1771 int cwd_fd = sp->fts_cwd_fd;
1772 cwd_fd = dup (cwd_fd);
1773 char *dot = getcwdat (cwd_fd, NULL, 0);
1774 error (0, 0, "===== check ===== cwd: %s", dot);
1776 while ( ! i_ring_empty (&fd_w))
1778 int fd = i_ring_pop (&fd_w);
1781 int parent_fd = openat (cwd_fd, "..", O_SEARCH | O_NOATIME);
1787 if (!same_fd (fd, parent_fd))
1789 char *cwd = getcwdat (fd, NULL, 0);
1790 error (0, errno, "ring : %s", cwd);
1791 char *c2 = getcwdat (parent_fd, NULL, 0);
1792 error (0, errno, "parent: %s", c2);
1805 static unsigned short int
1807 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1809 struct stat *sbp = p->fts_statp;
1812 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1816 * If doing a logical walk, or application requested FTS_FOLLOW, do
1817 * a stat(2). If that fails, check for a non-existent symlink. If
1818 * fail, set the errno from the stat call.
1820 if (ISSET(FTS_LOGICAL) || follow) {
1821 if (stat(p->fts_accpath, sbp)) {
1822 saved_errno = errno;
1824 && lstat(p->fts_accpath, sbp) == 0) {
1826 return (FTS_SLNONE);
1828 p->fts_errno = saved_errno;
1831 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1832 AT_SYMLINK_NOFOLLOW)) {
1833 p->fts_errno = errno;
1834 err: memset(sbp, 0, sizeof(struct stat));
1838 if (S_ISDIR(sbp->st_mode)) {
1839 p->fts_n_dirs_remaining = (sbp->st_nlink
1840 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1841 if (ISDOT(p->fts_name)) {
1842 /* Command-line "." and ".." are real directories. */
1843 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1848 if (S_ISLNK(sbp->st_mode))
1850 if (S_ISREG(sbp->st_mode))
1852 return (FTS_DEFAULT);
1856 fts_compar (void const *a, void const *b)
1858 /* Convert A and B to the correct types, to pacify the compiler, and
1859 for portability to bizarre hosts where "void const *" and "FTSENT
1860 const **" differ in runtime representation. The comparison
1861 function cannot modify *a and *b, but there is no compile-time
1863 FTSENT const **pa = (FTSENT const **) a;
1864 FTSENT const **pb = (FTSENT const **) b;
1865 return pa[0]->fts_fts->fts_compar (pa, pb);
1870 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1872 register FTSENT **ap, *p;
1874 /* On most modern hosts, void * and FTSENT ** have the same
1875 run-time representation, and one can convert sp->fts_compar to
1876 the type qsort expects without problem. Use the heuristic that
1877 this is OK if the two pointer types are the same size, and if
1878 converting FTSENT ** to long int is the same as converting
1879 FTSENT ** to void * and then to long int. This heuristic isn't
1880 valid in general but we don't know of any counterexamples. */
1882 int (*compare) (void const *, void const *) =
1883 ((sizeof &dummy == sizeof (void *)
1884 && (long int) &dummy == (long int) (void *) &dummy)
1885 ? (int (*) (void const *, void const *)) sp->fts_compar
1889 * Construct an array of pointers to the structures and call qsort(3).
1890 * Reassemble the array in the order returned by qsort. If unable to
1891 * sort for memory reasons, return the directory entries in their
1892 * current order. Allocate enough space for the current needs plus
1893 * 40 so don't realloc one entry at a time.
1895 if (nitems > sp->fts_nitems) {
1898 sp->fts_nitems = nitems + 40;
1899 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1900 || ! (a = realloc (sp->fts_array,
1901 sp->fts_nitems * sizeof *a))) {
1902 free(sp->fts_array);
1903 sp->fts_array = NULL;
1909 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1911 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1912 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1913 ap[0]->fts_link = ap[1];
1914 ap[0]->fts_link = NULL;
1920 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1926 * The file name is a variable length array. Allocate the FTSENT
1927 * structure and the file name in one chunk.
1929 len = FLEXSIZEOF(FTSENT, fts_name, namelen + 1);
1930 if ((p = malloc(len)) == NULL)
1933 /* Copy the name and guarantee NUL termination. */
1934 memcpy(p->fts_name, name, namelen);
1935 p->fts_name[namelen] = '\0';
1937 p->fts_namelen = namelen;
1939 p->fts_path = sp->fts_path;
1943 p->fts_instr = FTS_NOINSTR;
1945 p->fts_pointer = NULL;
1951 fts_lfree (register FTSENT *head)
1955 /* Free a linked list of structures. */
1956 while ((p = head)) {
1957 head = head->fts_link;
1959 closedir (p->fts_dirp);
1965 * Allow essentially unlimited file name lengths; find, rm, ls should
1966 * all work on any tree. Most systems will allow creation of file
1967 * names much longer than MAXPATHLEN, even though the kernel won't
1968 * resolve them. Add the size (not just what's needed) plus 256 bytes
1969 * so don't realloc the file name 2 bytes at a time.
1973 fts_palloc (FTS *sp, size_t more)
1976 size_t new_len = sp->fts_pathlen + more + 256;
1979 * See if fts_pathlen would overflow.
1981 if (new_len < sp->fts_pathlen) {
1983 sp->fts_path = NULL;
1984 __set_errno (ENAMETOOLONG);
1987 sp->fts_pathlen = new_len;
1988 p = realloc(sp->fts_path, sp->fts_pathlen);
1991 sp->fts_path = NULL;
1999 * When the file name is realloc'd, have to fix all of the pointers in
2000 * structures already returned.
2004 fts_padjust (FTS *sp, FTSENT *head)
2007 char *addr = sp->fts_path;
2009 #define ADJUST(p) do { \
2010 if ((p)->fts_accpath != (p)->fts_name) { \
2011 (p)->fts_accpath = \
2012 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
2014 (p)->fts_path = addr; \
2016 /* Adjust the current set of children. */
2017 for (p = sp->fts_child; p; p = p->fts_link)
2020 /* Adjust the rest of the tree, including the current level. */
2021 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
2023 p = p->fts_link ? p->fts_link : p->fts_parent;
2028 internal_function _GL_ATTRIBUTE_PURE
2029 fts_maxarglen (char * const *argv)
2033 for (max = 0; *argv; ++argv)
2034 if ((len = strlen(*argv)) > max)
2040 * Change to dir specified by fd or file name without getting
2041 * tricked by someone changing the world out from underneath us.
2042 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
2043 * If FD is non-negative, expect it to be used after this function returns,
2044 * and to be closed eventually. So don't pass e.g., 'dirfd(dirp)' and then
2045 * do closedir(dirp), because that would invalidate the saved FD.
2046 * Upon failure, close FD immediately and return nonzero.
2050 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
2053 bool is_dotdot = dir && STREQ (dir, "..");
2056 /* This clause handles the unusual case in which FTS_NOCHDIR
2057 is specified, along with FTS_CWDFD. In that case, there is
2058 no need to change even the virtual cwd file descriptor.
2059 However, if FD is non-negative, we do close it here. */
2060 if (ISSET (FTS_NOCHDIR))
2062 if (ISSET (FTS_CWDFD) && 0 <= fd)
2067 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
2069 /* When possible, skip the diropen and subsequent fstat+dev/ino
2070 comparison. I.e., when changing to parent directory
2071 (chdir ("..")), use a file descriptor from the ring and
2072 save the overhead of diropen+fstat, as well as avoiding
2073 failure when we lack "x" access to the virtual cwd. */
2074 if ( ! i_ring_empty (&sp->fts_fd_ring))
2077 fd_ring_print (sp, stderr, "pre-pop");
2078 parent_fd = i_ring_pop (&sp->fts_fd_ring);
2089 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
2092 /* The following dev/inode check is necessary if we're doing a
2093 "logical" traversal (through symlinks, a la chown -L), if the
2094 system lacks O_NOFOLLOW support, or if we're changing to ".."
2095 (but not via a popped file descriptor). When changing to the
2096 name "..", O_NOFOLLOW can't help. In general, when the target is
2097 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
2098 follow a symlink, so we can avoid the expense of this fstat. */
2099 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
2100 || (dir && STREQ (dir, "..")))
2103 if (fstat(newfd, &sb))
2108 if (p->fts_statp->st_dev != sb.st_dev
2109 || p->fts_statp->st_ino != sb.st_ino)
2111 __set_errno (ENOENT); /* disinformation */
2117 if (ISSET(FTS_CWDFD))
2119 cwd_advance_fd (sp, newfd, ! is_dotdot);
2123 ret = fchdir(newfd);
2129 __set_errno (oerrno);