1 /* Traverse a file hierarchy.
3 Copyright (C) 2004-2012 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 * Copyright (c) 1990, 1993, 1994
20 * The Regents of the University of California. All rights reserved.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the above copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 4. Neither the name of the University nor the names of its contributors
31 * may be used to endorse or promote products derived from this software
32 * without specific prior written permission.
34 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND
35 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
36 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
37 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
38 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
39 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
40 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
41 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
42 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
43 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
49 #if defined(LIBC_SCCS) && !defined(lint)
50 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
51 #endif /* LIBC_SCCS and not lint */
55 #if HAVE_SYS_PARAM_H || defined _LIBC
56 # include <sys/param.h>
59 # include <include/sys/stat.h>
61 # include <sys/stat.h>
72 # include "dirent--.h"
73 # include "unistd--.h"
74 /* FIXME - use fcntl(F_DUPFD_CLOEXEC)/openat(O_CLOEXEC) once they are
78 # include "same-inode.h"
82 #ifndef _D_EXACT_NAMLEN
83 # define _D_EXACT_NAMLEN(dirent) strlen ((dirent)->d_name)
86 #if HAVE_STRUCT_DIRENT_D_TYPE
87 /* True if the type of the directory entry D is known. */
88 # define DT_IS_KNOWN(d) ((d)->d_type != DT_UNKNOWN)
89 /* True if the type of the directory entry D must be T. */
90 # define DT_MUST_BE(d, t) ((d)->d_type == (t))
91 # define D_TYPE(d) ((d)->d_type)
93 # define DT_IS_KNOWN(d) false
94 # define DT_MUST_BE(d, t) false
95 # define D_TYPE(d) DT_UNKNOWN
100 /* Any nonzero values will do here, so long as they're distinct.
101 Undef any existing macros out of the way. */
127 NOT_AN_INODE_NUMBER = 0
130 #ifdef D_INO_IN_DIRENT
131 # define D_INO(dp) (dp)->d_ino
133 /* Some systems don't have inodes, so fake them to avoid lots of ifdefs. */
134 # define D_INO(dp) NOT_AN_INODE_NUMBER
137 /* If possible (see max_entries, below), read no more than this many directory
138 entries at a time. Without this limit (i.e., when using non-NULL
139 fts_compar), processing a directory with 4,000,000 entries requires ~1GiB
140 of memory, and handling 64M entries would require 16GiB of memory. */
141 #ifndef FTS_MAX_READDIR_ENTRIES
142 # define FTS_MAX_READDIR_ENTRIES 100000
145 /* If there are more than this many entries in a directory,
146 and the conditions mentioned below are satisfied, then sort
147 the entries on inode number before any further processing. */
148 #ifndef FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
149 # define FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD 10000
154 _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD = FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
159 FTS_NO_STAT_REQUIRED = 1,
160 FTS_STAT_REQUIRED = 2
165 # define close __close
167 # define closedir __closedir
169 # define fchdir __fchdir
173 # define readdir __readdir
175 # undef internal_function
176 # define internal_function /* empty */
180 # define __set_errno(Val) errno = (Val)
183 /* If this host provides the openat function, then we can avoid
184 attempting to open "." in some initialization code below. */
186 # define HAVE_OPENAT_SUPPORT 1
188 # define HAVE_OPENAT_SUPPORT 0
192 # define fts_assert(expr) ((void) 0)
194 # define fts_assert(expr) \
203 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
204 static FTSENT *fts_build (FTS *, int) internal_function;
205 static void fts_lfree (FTSENT *) internal_function;
206 static void fts_load (FTS *, FTSENT *) internal_function;
207 static size_t fts_maxarglen (char * const *) internal_function;
208 static void fts_padjust (FTS *, FTSENT *) internal_function;
209 static bool fts_palloc (FTS *, size_t) internal_function;
210 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
211 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
212 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
215 #include "fts-cycle.c"
218 # define MAX(a,b) ((a) > (b) ? (a) : (b))
222 # define SIZE_MAX ((size_t) -1)
225 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
226 #define STREQ(a, b) (strcmp (a, b) == 0)
228 #define CLR(opt) (sp->fts_options &= ~(opt))
229 #define ISSET(opt) (sp->fts_options & (opt))
230 #define SET(opt) (sp->fts_options |= (opt))
232 /* FIXME: FTS_NOCHDIR is now misnamed.
233 Call it FTS_USE_FULL_RELATIVE_FILE_NAMES instead. */
234 #define FCHDIR(sp, fd) \
235 (!ISSET(FTS_NOCHDIR) && (ISSET(FTS_CWDFD) \
236 ? (cwd_advance_fd ((sp), (fd), true), 0) \
240 /* fts_build flags */
241 /* FIXME: make this an enum */
242 #define BCHILD 1 /* fts_children */
243 #define BNAMES 2 /* fts_children, names only */
244 #define BREAD 3 /* fts_read */
247 # include <inttypes.h>
250 # include "getcwdat.h"
251 bool fts_debug = false;
252 # define Dprintf(x) do { if (fts_debug) printf x; } while (false)
255 # define fd_ring_check(x)
256 # define fd_ring_print(a, b, c)
259 #define LEAVE_DIR(Fts, Ent, Tag) \
262 Dprintf ((" %s-leaving: %s\n", Tag, (Ent)->fts_path)); \
263 leave_dir (Fts, Ent); \
264 fd_ring_check (Fts); \
269 fd_ring_clear (I_ring *fd_ring)
271 while ( ! i_ring_empty (fd_ring))
273 int fd = i_ring_pop (fd_ring);
279 /* Overload the fts_statp->st_size member (otherwise unused, when
280 fts_info is FTS_NSOK) to indicate whether fts_read should stat
281 this entry or not. */
283 fts_set_stat_required (FTSENT *p, bool required)
285 fts_assert (p->fts_info == FTS_NSOK);
286 p->fts_statp->st_size = (required
288 : FTS_NO_STAT_REQUIRED);
291 /* file-descriptor-relative opendir. */
292 /* FIXME: if others need this function, move it into lib/openat.c */
295 opendirat (int fd, char const *dir, int extra_flags, int *pdir_fd)
297 int new_fd = openat (fd, dir,
298 (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
304 set_cloexec_flag (new_fd, true);
305 dirp = fdopendir (new_fd);
310 int saved_errno = errno;
317 /* Virtual fchdir. Advance SP's working directory file descriptor,
318 SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
319 CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory
320 open on sp->fts_cwd_fd; i.e., to move the working directory one level
324 cwd_advance_fd (FTS *sp, int fd, bool chdir_down_one)
326 int old = sp->fts_cwd_fd;
327 fts_assert (old != fd || old == AT_FDCWD);
331 /* Push "old" onto the ring.
332 If the displaced file descriptor is non-negative, close it. */
333 int prev_fd_in_slot = i_ring_push (&sp->fts_fd_ring, old);
334 fd_ring_print (sp, stderr, "post-push");
335 if (0 <= prev_fd_in_slot)
336 close (prev_fd_in_slot); /* ignore any close failure */
338 else if ( ! ISSET (FTS_NOCHDIR))
341 close (old); /* ignore any close failure */
347 /* Restore the initial, pre-traversal, "working directory".
348 In FTS_CWDFD mode, we merely call cwd_advance_fd, otherwise,
349 we may actually change the working directory.
350 Return 0 upon success. Upon failure, set errno and return nonzero. */
352 restore_initial_cwd (FTS *sp)
354 int fail = FCHDIR (sp, ISSET (FTS_CWDFD) ? AT_FDCWD : sp->fts_rfd);
355 fd_ring_clear (&(sp->fts_fd_ring));
359 /* Open the directory DIR if possible, and return a file
360 descriptor. Return -1 and set errno on failure. It doesn't matter
361 whether the file descriptor has read or write access. */
365 diropen (FTS const *sp, char const *dir)
367 int open_flags = (O_SEARCH | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
368 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0)
369 | (ISSET (FTS_NOATIME) ? O_NOATIME : 0));
371 int fd = (ISSET (FTS_CWDFD)
372 ? openat (sp->fts_cwd_fd, dir, open_flags)
373 : open (dir, open_flags));
375 set_cloexec_flag (fd, true);
380 fts_open (char * const *argv,
381 register int options,
382 int (*compar) (FTSENT const **, FTSENT const **))
385 register FTSENT *p, *root;
386 register size_t nitems;
387 FTSENT *parent = NULL;
388 FTSENT *tmp = NULL; /* pacify gcc */
392 if (options & ~FTS_OPTIONMASK) {
393 __set_errno (EINVAL);
396 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
397 __set_errno (EINVAL);
400 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
401 __set_errno (EINVAL);
405 /* Allocate/initialize the stream */
406 if ((sp = malloc(sizeof(FTS))) == NULL)
408 memset(sp, 0, sizeof(FTS));
409 sp->fts_compar = compar;
410 sp->fts_options = options;
412 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
413 if (ISSET(FTS_LOGICAL)) {
418 /* Initialize fts_cwd_fd. */
419 sp->fts_cwd_fd = AT_FDCWD;
420 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
422 /* While it isn't technically necessary to open "." this
423 early, doing it here saves us the trouble of ensuring
424 later (where it'd be messier) that "." can in fact
425 be opened. If not, revert to FTS_NOCHDIR mode. */
427 O_SEARCH | (ISSET (FTS_NOATIME) ? O_NOATIME : 0));
430 /* Even if "." is unreadable, don't revert to FTS_NOCHDIR mode
431 on systems like Linux+PROC_FS, where our openat emulation
432 is good enough. Note: on a system that emulates
433 openat via /proc, this technique can still fail, but
434 only in extreme conditions, e.g., when the working
435 directory cannot be saved (i.e. save_cwd fails) --
436 and that happens on Linux only when "." is unreadable
437 and the CWD would be longer than PATH_MAX.
438 FIXME: once Linux kernel openat support is well established,
439 replace the above open call and this entire if/else block
440 with the body of the if-block below. */
441 if ( openat_needs_fchdir ())
454 * Start out with 1K of file name space, and enough, in any case,
455 * to hold the user's file names.
458 # define MAXPATHLEN 1024
461 size_t maxarglen = fts_maxarglen(argv);
462 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
466 /* Allocate/initialize root's parent. */
468 if ((parent = fts_alloc(sp, "", 0)) == NULL)
470 parent->fts_level = FTS_ROOTPARENTLEVEL;
473 /* The classic fts implementation would call fts_stat with
474 a new entry for each iteration of the loop below.
475 If the comparison function is not specified or if the
476 FTS_DEFER_STAT option is in effect, don't stat any entry
477 in this loop. This is an attempt to minimize the interval
478 between the initial stat/lstat/fstatat and the point at which
479 a directory argument is first opened. This matters for any
480 directory command line argument that resides on a file system
481 without genuine i-nodes. If you specify FTS_DEFER_STAT along
482 with a comparison function, that function must not access any
483 data via the fts_statp pointer. */
484 defer_stat = (compar == NULL || ISSET(FTS_DEFER_STAT));
486 /* Allocate/initialize root(s). */
487 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
488 /* *Do* allow zero-length file names. */
489 size_t len = strlen(*argv);
491 if ( ! (options & FTS_VERBATIM))
493 /* If there are two or more trailing slashes, trim all but one,
494 but don't change "//" to "/", and do map "///" to "/". */
495 char const *v = *argv;
496 if (2 < len && v[len - 1] == '/')
497 while (1 < len && v[len - 2] == '/')
501 if ((p = fts_alloc(sp, *argv, len)) == NULL)
503 p->fts_level = FTS_ROOTLEVEL;
504 p->fts_parent = parent;
505 p->fts_accpath = p->fts_name;
506 /* Even when defer_stat is true, be sure to stat the first
507 command line argument, since fts_read (at least with
508 FTS_XDEV) requires that. */
509 if (defer_stat && root != NULL) {
510 p->fts_info = FTS_NSOK;
511 fts_set_stat_required(p, true);
513 p->fts_info = fts_stat(sp, p, false);
517 * If comparison routine supplied, traverse in sorted
518 * order; otherwise traverse in the order specified.
533 if (compar && nitems > 1)
534 root = fts_sort(sp, root, nitems);
537 * Allocate a dummy pointer and make fts_read think that we've just
538 * finished the node before the root(s); set p->fts_info to FTS_INIT
539 * so that everything about the "current" node is ignored.
541 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
543 sp->fts_cur->fts_link = root;
544 sp->fts_cur->fts_info = FTS_INIT;
545 if (! setup_dir (sp))
549 * If using chdir(2), grab a file descriptor pointing to dot to ensure
550 * that we can get back here; this could be avoided for some file names,
551 * but almost certainly not worth the effort. Slashes, symbolic links,
552 * and ".." are all fairly nasty problems. Note, if we can't get the
553 * descriptor we run anyway, just more slowly.
555 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
556 && (sp->fts_rfd = diropen (sp, ".")) < 0)
559 i_ring_init (&sp->fts_fd_ring, -1);
562 mem3: fts_lfree(root);
564 mem2: free(sp->fts_path);
571 fts_load (FTS *sp, register FTSENT *p)
577 * Load the stream structure for the next traversal. Since we don't
578 * actually enter the directory until after the preorder visit, set
579 * the fts_accpath field specially so the chdir gets done to the right
580 * place and the user can access the first node. From fts_open it's
581 * known that the file name will fit.
583 len = p->fts_pathlen = p->fts_namelen;
584 memmove(sp->fts_path, p->fts_name, len + 1);
585 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
587 memmove(p->fts_name, cp, len + 1);
588 p->fts_namelen = len;
590 p->fts_accpath = p->fts_path = sp->fts_path;
596 register FTSENT *freep, *p;
600 * This still works if we haven't read anything -- the dummy structure
601 * points to the root list, so we step through to the end of the root
602 * list which has a valid parent pointer.
605 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
607 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
613 /* Free up child linked list, sort array, file name buffer. */
615 fts_lfree(sp->fts_child);
619 if (ISSET(FTS_CWDFD))
621 if (0 <= sp->fts_cwd_fd)
622 if (close (sp->fts_cwd_fd))
625 else if (!ISSET(FTS_NOCHDIR))
627 /* Return to original directory, save errno if necessary. */
628 if (fchdir(sp->fts_rfd))
631 /* If close fails, record errno only if saved_errno is zero,
632 so that we report the probably-more-meaningful fchdir errno. */
633 if (close (sp->fts_rfd))
634 if (saved_errno == 0)
638 fd_ring_clear (&sp->fts_fd_ring);
640 if (sp->fts_leaf_optimization_works_ht)
641 hash_free (sp->fts_leaf_optimization_works_ht);
645 /* Free up the stream pointer. */
648 /* Set errno and return. */
650 __set_errno (saved_errno);
657 #if defined __linux__ \
658 && HAVE_SYS_VFS_H && HAVE_FSTATFS && HAVE_STRUCT_STATFS_F_TYPE
660 # include <sys/vfs.h>
662 /* Linux-specific constants from coreutils' src/fs.h */
663 # define S_MAGIC_TMPFS 0x1021994
664 # define S_MAGIC_NFS 0x6969
665 # define S_MAGIC_REISERFS 0x52654973
666 # define S_MAGIC_PROC 0x9FA0
668 /* Return false if it is easy to determine the file system type of
669 the directory on which DIR_FD is open, and sorting dirents on
670 inode numbers is known not to improve traversal performance with
671 that type of file system. Otherwise, return true. */
673 dirent_inode_sort_may_be_useful (int dir_fd)
675 /* Skip the sort only if we can determine efficiently
676 that skipping it is the right thing to do.
677 The cost of performing an unnecessary sort is negligible,
678 while the cost of *not* performing it can be O(N^2) with
679 a very large constant. */
680 struct statfs fs_buf;
682 /* If fstatfs fails, assume sorting would be useful. */
683 if (fstatfs (dir_fd, &fs_buf) != 0)
686 /* FIXME: what about when f_type is not an integral type?
687 deal with that if/when it's encountered. */
688 switch (fs_buf.f_type)
692 /* On a file system of any of these types, sorting
693 is unnecessary, and hence wasteful. */
701 /* Given a file descriptor DIR_FD open on a directory D,
702 return true if it is valid to apply the leaf-optimization
703 technique of counting directories in D via stat.st_nlink. */
705 leaf_optimization_applies (int dir_fd)
707 struct statfs fs_buf;
709 /* If fstatfs fails, assume we can't use the optimization. */
710 if (fstatfs (dir_fd, &fs_buf) != 0)
713 /* FIXME: do we need to detect AFS mount points? I doubt it,
714 unless fstatfs can report S_MAGIC_REISERFS for such a directory. */
716 switch (fs_buf.f_type)
718 /* List here the file system types that lack usable dirent.d_type
719 info, yet for which the optimization does apply. */
720 case S_MAGIC_REISERFS:
724 /* Explicitly listing this or any other file system type for which
725 the optimization is not applicable is not necessary, but we leave
726 it here to document the risk. Per http://bugs.debian.org/143111,
727 /proc may have bogus stat.st_nlink values. */
736 dirent_inode_sort_may_be_useful (int dir_fd _GL_UNUSED) { return true; }
738 leaf_optimization_applies (int dir_fd _GL_UNUSED) { return false; }
741 /* link-count-optimization entry:
742 map a stat.st_dev number to a boolean: leaf_optimization_works */
749 /* Use a tiny initial size. If a traversal encounters more than
750 a few devices, the cost of growing/rehashing this table will be
751 rendered negligible by the number of inodes processed. */
752 enum { LCO_HT_INITIAL_SIZE = 13 };
755 LCO_hash (void const *x, size_t table_size)
757 struct LCO_ent const *ax = x;
758 return (uintmax_t) ax->st_dev % table_size;
762 LCO_compare (void const *x, void const *y)
764 struct LCO_ent const *ax = x;
765 struct LCO_ent const *ay = y;
766 return ax->st_dev == ay->st_dev;
769 /* Ask the same question as leaf_optimization_applies, but query
770 the cache first (FTS.fts_leaf_optimization_works_ht), and if necessary,
771 update that cache. */
773 link_count_optimize_ok (FTSENT const *p)
775 FTS *sp = p->fts_fts;
776 Hash_table *h = sp->fts_leaf_optimization_works_ht;
782 /* If we're not in CWDFD mode, don't bother with this optimization,
783 since the caller is not serious about performance. */
784 if (!ISSET(FTS_CWDFD))
787 /* map st_dev to the boolean, leaf_optimization_works */
790 h = sp->fts_leaf_optimization_works_ht
791 = hash_initialize (LCO_HT_INITIAL_SIZE, NULL, LCO_hash,
796 tmp.st_dev = p->fts_statp->st_dev;
797 ent = hash_lookup (h, &tmp);
801 /* Look-up failed. Query directly and cache the result. */
802 t2 = malloc (sizeof *t2);
806 /* Is it ok to perform the optimization in the dir, FTS_CWD_FD? */
807 opt_ok = leaf_optimization_applies (sp->fts_cwd_fd);
809 t2->st_dev = p->fts_statp->st_dev;
811 ent = hash_insert (h, t2);
814 /* insertion failed */
818 fts_assert (ent == t2);
824 * Special case of "/" at the end of the file name so that slashes aren't
825 * appended which would cause file names to be written as "....//foo".
828 (p->fts_path[p->fts_pathlen - 1] == '/' \
829 ? p->fts_pathlen - 1 : p->fts_pathlen)
832 fts_read (register FTS *sp)
834 register FTSENT *p, *tmp;
835 register unsigned short int instr;
838 /* If finished or unrecoverable error, return NULL. */
839 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
842 /* Set current node pointer. */
845 /* Save and zero out user instructions. */
846 instr = p->fts_instr;
847 p->fts_instr = FTS_NOINSTR;
849 /* Any type of file may be re-visited; re-stat and re-turn. */
850 if (instr == FTS_AGAIN) {
851 p->fts_info = fts_stat(sp, p, false);
854 Dprintf (("fts_read: p=%s\n",
855 p->fts_info == FTS_INIT ? "" : p->fts_path));
858 * Following a symlink -- SLNONE test allows application to see
859 * SLNONE and recover. If indirecting through a symlink, have
860 * keep a pointer to current location. If unable to get that
861 * pointer, follow fails.
863 if (instr == FTS_FOLLOW &&
864 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
865 p->fts_info = fts_stat(sp, p, true);
866 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
867 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
868 p->fts_errno = errno;
869 p->fts_info = FTS_ERR;
871 p->fts_flags |= FTS_SYMFOLLOW;
876 /* Directory in pre-order. */
877 if (p->fts_info == FTS_D) {
878 /* If skipped or crossed mount point, do post-order visit. */
879 if (instr == FTS_SKIP ||
880 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
881 if (p->fts_flags & FTS_SYMFOLLOW)
882 (void)close(p->fts_symfd);
884 fts_lfree(sp->fts_child);
885 sp->fts_child = NULL;
887 p->fts_info = FTS_DP;
888 LEAVE_DIR (sp, p, "1");
892 /* Rebuild if only read the names and now traversing. */
893 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
895 fts_lfree(sp->fts_child);
896 sp->fts_child = NULL;
900 * Cd to the subdirectory.
902 * If have already read and now fail to chdir, whack the list
903 * to make the names come out right, and set the parent errno
904 * so the application will eventually get an error condition.
905 * Set the FTS_DONTCHDIR flag so that when we logically change
906 * directories back to the parent we don't do a chdir.
908 * If haven't read do so. If the read fails, fts_build sets
909 * FTS_STOP or the fts_info field of the node.
911 if (sp->fts_child != NULL) {
912 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
913 p->fts_errno = errno;
914 p->fts_flags |= FTS_DONTCHDIR;
915 for (p = sp->fts_child; p != NULL;
918 p->fts_parent->fts_accpath;
920 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
923 /* If fts_build's call to fts_safe_changedir failed
924 because it was not able to fchdir into a
925 subdirectory, tell the caller. */
926 if (p->fts_errno && p->fts_info != FTS_DNR)
927 p->fts_info = FTS_ERR;
928 LEAVE_DIR (sp, p, "2");
932 sp->fts_child = NULL;
936 /* Move to the next node on this level. */
939 /* If we have so many directory entries that we're reading them
940 in batches, and we've reached the end of the current batch,
941 read in a new batch. */
942 if (p->fts_link == NULL && p->fts_parent->fts_dirp)
946 sp->fts_path[p->fts_pathlen] = '\0';
948 if ((p = fts_build (sp, BREAD)) == NULL)
959 if ((p = p->fts_link) != NULL) {
964 * If reached the top, return to the original directory (or
965 * the root of the tree), and load the file names for the next
968 if (p->fts_level == FTS_ROOTLEVEL) {
969 if (restore_initial_cwd(sp)) {
980 * User may have called fts_set on the node. If skipped,
981 * ignore. If followed, get a file descriptor so we can
982 * get back if necessary.
984 if (p->fts_instr == FTS_SKIP)
986 if (p->fts_instr == FTS_FOLLOW) {
987 p->fts_info = fts_stat(sp, p, true);
988 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
989 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
990 p->fts_errno = errno;
991 p->fts_info = FTS_ERR;
993 p->fts_flags |= FTS_SYMFOLLOW;
995 p->fts_instr = FTS_NOINSTR;
998 name: t = sp->fts_path + NAPPEND(p->fts_parent);
1000 memmove(t, p->fts_name, p->fts_namelen + 1);
1003 if (p->fts_info == FTS_NSOK)
1005 if (p->fts_statp->st_size == FTS_STAT_REQUIRED)
1007 FTSENT *parent = p->fts_parent;
1008 if (FTS_ROOTLEVEL < p->fts_level
1009 /* ->fts_n_dirs_remaining is not valid
1010 for command-line-specified names. */
1011 && parent->fts_n_dirs_remaining == 0
1012 && ISSET(FTS_NOSTAT)
1013 && ISSET(FTS_PHYSICAL)
1014 && link_count_optimize_ok (parent))
1016 /* nothing more needed */
1020 p->fts_info = fts_stat(sp, p, false);
1021 if (S_ISDIR(p->fts_statp->st_mode)
1022 && p->fts_level != FTS_ROOTLEVEL
1023 && parent->fts_n_dirs_remaining)
1024 parent->fts_n_dirs_remaining--;
1028 fts_assert (p->fts_statp->st_size == FTS_NO_STAT_REQUIRED);
1031 if (p->fts_info == FTS_D)
1033 /* Now that P->fts_statp is guaranteed to be valid,
1034 if this is a command-line directory, record its
1035 device number, to be used for FTS_XDEV. */
1036 if (p->fts_level == FTS_ROOTLEVEL)
1037 sp->fts_dev = p->fts_statp->st_dev;
1038 Dprintf ((" entering: %s\n", p->fts_path));
1039 if (! enter_dir (sp, p))
1041 __set_errno (ENOMEM);
1049 /* Move up to the parent node. */
1050 p = tmp->fts_parent;
1054 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
1056 * Done; free everything up and set errno to 0 so the user
1057 * can distinguish between error and EOF.
1061 return (sp->fts_cur = NULL);
1064 fts_assert (p->fts_info != FTS_NSOK);
1066 /* NUL terminate the file name. */
1067 sp->fts_path[p->fts_pathlen] = '\0';
1070 * Return to the parent directory. If at a root node, restore
1071 * the initial working directory. If we came through a symlink,
1072 * go back through the file descriptor. Otherwise, move up
1073 * one level, via "..".
1075 if (p->fts_level == FTS_ROOTLEVEL) {
1076 if (restore_initial_cwd(sp)) {
1077 p->fts_errno = errno;
1080 } else if (p->fts_flags & FTS_SYMFOLLOW) {
1081 if (FCHDIR(sp, p->fts_symfd)) {
1082 int saved_errno = errno;
1083 (void)close(p->fts_symfd);
1084 __set_errno (saved_errno);
1085 p->fts_errno = errno;
1088 (void)close(p->fts_symfd);
1089 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
1090 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
1091 p->fts_errno = errno;
1094 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
1095 if (p->fts_errno == 0)
1096 LEAVE_DIR (sp, p, "3");
1097 return ISSET(FTS_STOP) ? NULL : p;
1101 * Fts_set takes the stream as an argument although it's not used in this
1102 * implementation; it would be necessary if anyone wanted to add global
1103 * semantics to fts using fts_set. An error return is allowed for similar
1108 fts_set(FTS *sp _GL_UNUSED, FTSENT *p, int instr)
1110 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
1111 instr != FTS_NOINSTR && instr != FTS_SKIP) {
1112 __set_errno (EINVAL);
1115 p->fts_instr = instr;
1120 fts_children (register FTS *sp, int instr)
1125 if (instr != 0 && instr != FTS_NAMEONLY) {
1126 __set_errno (EINVAL);
1130 /* Set current node pointer. */
1134 * Errno set to 0 so user can distinguish empty directory from
1139 /* Fatal errors stop here. */
1140 if (ISSET(FTS_STOP))
1143 /* Return logical hierarchy of user's arguments. */
1144 if (p->fts_info == FTS_INIT)
1145 return (p->fts_link);
1148 * If not a directory being visited in pre-order, stop here. Could
1149 * allow FTS_DNR, assuming the user has fixed the problem, but the
1150 * same effect is available with FTS_AGAIN.
1152 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
1155 /* Free up any previous child list. */
1156 if (sp->fts_child != NULL)
1157 fts_lfree(sp->fts_child);
1159 if (instr == FTS_NAMEONLY) {
1166 * If using chdir on a relative file name and called BEFORE fts_read
1167 * does its chdir to the root of a traversal, we can lose -- we need to
1168 * chdir into the subdirectory, and we don't know where the current
1169 * directory is, so we can't get back so that the upcoming chdir by
1170 * fts_read will work.
1172 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
1174 return (sp->fts_child = fts_build(sp, instr));
1176 if ((fd = diropen (sp, ".")) < 0)
1177 return (sp->fts_child = NULL);
1178 sp->fts_child = fts_build(sp, instr);
1179 if (ISSET(FTS_CWDFD))
1181 cwd_advance_fd (sp, fd, true);
1187 int saved_errno = errno;
1189 __set_errno (saved_errno);
1194 return (sp->fts_child);
1197 /* A comparison function to sort on increasing inode number.
1198 For some file system types, sorting either way makes a huge
1199 performance difference for a directory with very many entries,
1200 but sorting on increasing values is slightly better than sorting
1201 on decreasing values. The difference is in the 5% range. */
1203 fts_compare_ino (struct _ftsent const **a, struct _ftsent const **b)
1205 return (a[0]->fts_statp->st_ino < b[0]->fts_statp->st_ino ? -1
1206 : b[0]->fts_statp->st_ino < a[0]->fts_statp->st_ino ? 1 : 0);
1209 /* Map the dirent.d_type value, DTYPE, to the corresponding stat.st_mode
1210 S_IF* bit and set ST.st_mode, thus clearing all other bits in that field. */
1212 set_stat_type (struct stat *st, unsigned int dtype)
1244 #define closedir_and_clear(dirp) \
1252 #define fts_opendir(file, Pdir_fd) \
1253 opendirat((! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
1254 ? sp->fts_cwd_fd : AT_FDCWD), \
1256 (((ISSET(FTS_PHYSICAL) \
1257 && ! (ISSET(FTS_COMFOLLOW) \
1258 && cur->fts_level == FTS_ROOTLEVEL)) \
1260 | (ISSET (FTS_NOATIME) ? O_NOATIME : 0)), \
1264 * This is the tricky part -- do not casually change *anything* in here. The
1265 * idea is to build the linked list of entries that are used by fts_children
1266 * and fts_read. There are lots of special cases.
1268 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
1269 * set and it's a physical walk (so that symbolic links can't be directories),
1270 * we can do things quickly. First, if it's a 4.4BSD file system, the type
1271 * of the file is in the directory entry. Otherwise, we assume that the number
1272 * of subdirectories in a node is equal to the number of links to the parent.
1273 * The former skips all stat calls. The latter skips stat calls in any leaf
1274 * directories and for any files after the subdirectories in the directory have
1275 * been found, cutting the stat calls by about 2/3.
1279 fts_build (register FTS *sp, int type)
1281 register FTSENT *p, *head;
1282 register size_t nitems;
1291 size_t len, maxlen, new_len;
1294 FTSENT *cur = sp->fts_cur;
1295 bool continue_readdir = !!cur->fts_dirp;
1297 /* When cur->fts_dirp is non-NULL, that means we should
1298 continue calling readdir on that existing DIR* pointer
1299 rather than opening a new one. */
1300 if (continue_readdir)
1302 DIR *dp = cur->fts_dirp;
1303 dir_fd = dirfd (dp);
1306 closedir_and_clear (cur->fts_dirp);
1309 cur->fts_info = FTS_DNR;
1310 cur->fts_errno = errno;
1317 /* Open the directory for reading. If this fails, we're done.
1318 If being called from fts_read, set the fts_info field. */
1319 if ((cur->fts_dirp = fts_opendir(cur->fts_accpath, &dir_fd)) == NULL)
1323 cur->fts_info = FTS_DNR;
1324 cur->fts_errno = errno;
1328 /* Rather than calling fts_stat for each and every entry encountered
1329 in the readdir loop (below), stat each directory only right after
1331 if (cur->fts_info == FTS_NSOK)
1332 cur->fts_info = fts_stat(sp, cur, false);
1333 else if (sp->fts_options & FTS_TIGHT_CYCLE_CHECK)
1335 /* Now read the stat info again after opening a directory to
1336 reveal eventual changes caused by a submount triggered by
1337 the traversal. But do it only for utilities which use
1338 FTS_TIGHT_CYCLE_CHECK. Therefore, only find and du
1339 benefit/suffer from this feature for now. */
1340 LEAVE_DIR (sp, cur, "4");
1341 fts_stat (sp, cur, false);
1342 if (! enter_dir (sp, cur))
1344 __set_errno (ENOMEM);
1350 /* Maximum number of readdir entries to read at one time. This
1351 limitation is to avoid reading millions of entries into memory
1352 at once. When an fts_compar function is specified, we have no
1353 choice: we must read all entries into memory before calling that
1354 function. But when no such function is specified, we can read
1355 entries in batches that are large enough to help us with inode-
1356 sorting, yet not so large that we risk exhausting memory. */
1357 size_t max_entries = (sp->fts_compar == NULL
1358 ? FTS_MAX_READDIR_ENTRIES : SIZE_MAX);
1361 * Nlinks is the number of possible entries of type directory in the
1362 * directory if we're cheating on stat calls, 0 if we're not doing
1363 * any stat calls at all, (nlink_t) -1 if we're statting everything.
1365 if (type == BNAMES) {
1367 /* Be quiet about nostat, GCC. */
1369 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
1370 nlinks = (cur->fts_statp->st_nlink
1371 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1379 * If we're going to need to stat anything or we want to descend
1380 * and stay in the directory, chdir. If this fails we keep going,
1381 * but set a flag so we don't chdir after the post-order visit.
1382 * We won't be able to stat anything, but we can still return the
1383 * names themselves. Note, that since fts_read won't be able to
1384 * chdir into the directory, it will have to return different file
1385 * names than before, i.e. "a/b" instead of "b". Since the node
1386 * has already been visited in pre-order, have to wait until the
1387 * post-order visit to return the error. There is a special case
1388 * here, if there was nothing to stat then it's not an error to
1389 * not be able to stat. This is all fairly nasty. If a program
1390 * needed sorted entries or stat information, they had better be
1391 * checking FTS_NS on the returned nodes.
1393 if (continue_readdir)
1395 /* When resuming a short readdir run, we already have
1396 the required dirp and dir_fd. */
1399 else if (nlinks || type == BREAD) {
1400 if (ISSET(FTS_CWDFD))
1402 dir_fd = dup (dir_fd);
1404 set_cloexec_flag (dir_fd, true);
1406 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1407 if (nlinks && type == BREAD)
1408 cur->fts_errno = errno;
1409 cur->fts_flags |= FTS_DONTCHDIR;
1411 closedir_and_clear(cur->fts_dirp);
1412 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1414 cur->fts_dirp = NULL;
1421 * Figure out the max file name length that can be stored in the
1422 * current buffer -- the inner loop allocates more space as necessary.
1423 * We really wouldn't have to do the maxlen calculations here, we
1424 * could do them in fts_read before returning the name, but it's a
1425 * lot easier here since the length is part of the dirent structure.
1427 * If not changing directories set a pointer so that can just append
1428 * each new component into the file name.
1431 if (ISSET(FTS_NOCHDIR)) {
1432 cp = sp->fts_path + len;
1435 /* GCC, you're too verbose. */
1439 maxlen = sp->fts_pathlen - len;
1441 level = cur->fts_level + 1;
1443 /* Read the directory, attaching each entry to the "link" pointer. */
1448 while (cur->fts_dirp) {
1450 struct dirent *dp = readdir(cur->fts_dirp);
1453 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1456 if ((p = fts_alloc (sp, dp->d_name,
1457 _D_EXACT_NAMLEN (dp))) == NULL)
1459 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
1460 /* include space for NUL */
1461 oldaddr = sp->fts_path;
1462 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
1464 * No more memory. Save
1465 * errno, free up the current structure and the
1466 * structures already allocated.
1468 mem1: saved_errno = errno;
1471 closedir_and_clear(cur->fts_dirp);
1472 cur->fts_info = FTS_ERR;
1474 __set_errno (saved_errno);
1477 /* Did realloc() change the pointer? */
1478 if (oldaddr != sp->fts_path) {
1480 if (ISSET(FTS_NOCHDIR))
1481 cp = sp->fts_path + len;
1483 maxlen = sp->fts_pathlen - len;
1486 new_len = len + _D_EXACT_NAMLEN (dp);
1487 if (new_len < len) {
1489 * In the unlikely event that we would end up
1490 * with a file name longer than SIZE_MAX, free up
1491 * the current structure and the structures already
1492 * allocated, then error out with ENAMETOOLONG.
1496 closedir_and_clear(cur->fts_dirp);
1497 cur->fts_info = FTS_ERR;
1499 __set_errno (ENAMETOOLONG);
1502 p->fts_level = level;
1503 p->fts_parent = sp->fts_cur;
1504 p->fts_pathlen = new_len;
1506 /* Store dirent.d_ino, in case we need to sort
1507 entries before processing them. */
1508 p->fts_statp->st_ino = D_INO (dp);
1510 /* Build a file name for fts_stat to stat. */
1511 if (ISSET(FTS_NOCHDIR)) {
1512 p->fts_accpath = p->fts_path;
1513 memmove(cp, p->fts_name, p->fts_namelen + 1);
1515 p->fts_accpath = p->fts_name;
1517 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1518 /* Record what fts_read will have to do with this
1519 entry. In many cases, it will simply fts_stat it,
1520 but we can take advantage of any d_type information
1521 to optimize away the unnecessary stat calls. I.e.,
1522 if FTS_NOSTAT is in effect and we're not following
1523 symlinks (FTS_PHYSICAL) and d_type indicates this
1524 is *not* a directory, then we won't have to stat it
1525 at all. If it *is* a directory, then (currently)
1526 we stat it regardless, in order to get device and
1527 inode numbers. Some day we might optimize that
1528 away, too, for directories where d_ino is known to
1530 bool skip_stat = (ISSET(FTS_PHYSICAL)
1531 && ISSET(FTS_NOSTAT)
1533 && ! DT_MUST_BE(dp, DT_DIR));
1534 p->fts_info = FTS_NSOK;
1535 /* Propagate dirent.d_type information back
1536 to caller, when possible. */
1537 set_stat_type (p->fts_statp, D_TYPE (dp));
1538 fts_set_stat_required(p, !skip_stat);
1539 is_dir = (ISSET(FTS_PHYSICAL)
1540 && DT_MUST_BE(dp, DT_DIR));
1542 p->fts_info = fts_stat(sp, p, false);
1543 is_dir = (p->fts_info == FTS_D
1544 || p->fts_info == FTS_DC
1545 || p->fts_info == FTS_DOT);
1548 /* Decrement link count if applicable. */
1549 if (nlinks > 0 && is_dir)
1552 /* We walk in directory order so "ls -f" doesn't get upset. */
1561 if (max_entries <= nitems) {
1562 /* When there are too many dir entries, leave
1563 fts_dirp open, so that a subsequent fts_read
1564 can take up where we leave off. */
1565 goto break_without_closedir;
1570 closedir_and_clear(cur->fts_dirp);
1572 break_without_closedir:
1575 * If realloc() changed the address of the file name, adjust the
1576 * addresses for the rest of the tree and the dir list.
1579 fts_padjust(sp, head);
1582 * If not changing directories, reset the file name back to original
1585 if (ISSET(FTS_NOCHDIR)) {
1586 if (len == sp->fts_pathlen || nitems == 0)
1592 * If descended after called from fts_children or after called from
1593 * fts_read and nothing found, get back. At the root level we use
1594 * the saved fd; if one of fts_open()'s arguments is a relative name
1595 * to an empty directory, we wind up here with no other way back. If
1596 * can't get back, we're done.
1598 if (!continue_readdir && descend && (type == BCHILD || !nitems) &&
1599 (cur->fts_level == FTS_ROOTLEVEL
1600 ? restore_initial_cwd(sp)
1601 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1602 cur->fts_info = FTS_ERR;
1608 /* If didn't find anything, return NULL. */
1611 cur->fts_info = FTS_DP;
1616 /* If there are many entries, no sorting function has been specified,
1617 and this file system is of a type that may be slow with a large
1618 number of entries, then sort the directory entries on increasing
1620 if (nitems > _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
1622 && ISSET (FTS_CWDFD)
1623 && dirent_inode_sort_may_be_useful (sp->fts_cwd_fd)) {
1624 sp->fts_compar = fts_compare_ino;
1625 head = fts_sort (sp, head, nitems);
1626 sp->fts_compar = NULL;
1629 /* Sort the entries. */
1630 if (sp->fts_compar && nitems > 1)
1631 head = fts_sort(sp, head, nitems);
1637 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1638 current hierarchy. There should be a directory with dev/inode
1639 matching those of AD. If not, print a lot of diagnostics. */
1641 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1644 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1646 if (ad->ino == ent->fts_statp->st_ino
1647 && ad->dev == ent->fts_statp->st_dev)
1650 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1651 printf ("active dirs:\n");
1653 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1654 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1655 ad->fts_ent->fts_accpath,
1656 (uintmax_t) ad->dev,
1657 (uintmax_t) ad->ino,
1659 (uintmax_t) ent->fts_statp->st_dev,
1660 (uintmax_t) ent->fts_statp->st_ino);
1664 fts_cross_check (FTS const *sp)
1666 FTSENT const *ent = sp->fts_cur;
1668 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1671 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1672 /* Make sure every parent dir is in the tree. */
1673 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1675 struct Active_dir ad;
1676 ad.ino = t->fts_statp->st_ino;
1677 ad.dev = t->fts_statp->st_dev;
1678 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1679 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1682 /* Make sure every dir in the tree is an active dir.
1683 But ENT is not necessarily a directory. If so, just skip this part. */
1684 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1685 && (ent->fts_info == FTS_DP
1686 || ent->fts_info == FTS_D))
1688 struct Active_dir *ad;
1689 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1690 ad = hash_get_next (sp->fts_cycle.ht, ad))
1692 find_matching_ancestor (ent, ad);
1698 same_fd (int fd1, int fd2)
1700 struct stat sb1, sb2;
1701 return (fstat (fd1, &sb1) == 0
1702 && fstat (fd2, &sb2) == 0
1703 && SAME_INODE (sb1, sb2));
1707 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1709 I_ring const *fd_ring = &sp->fts_fd_ring;
1710 unsigned int i = fd_ring->fts_front;
1711 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1712 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1714 if (i_ring_empty (fd_ring))
1719 int fd = fd_ring->fts_fd_ring[i];
1721 fprintf (stream, "%d: %d:\n", i, fd);
1724 char *wd = getcwdat (fd, NULL, 0);
1725 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1728 if (i == fd_ring->fts_back)
1730 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1734 /* Ensure that each file descriptor on the fd_ring matches a
1735 parent, grandparent, etc. of the current working directory. */
1737 fd_ring_check (FTS const *sp)
1742 /* Make a writable copy. */
1743 I_ring fd_w = sp->fts_fd_ring;
1745 int cwd_fd = sp->fts_cwd_fd;
1746 cwd_fd = dup (cwd_fd);
1747 char *dot = getcwdat (cwd_fd, NULL, 0);
1748 error (0, 0, "===== check ===== cwd: %s", dot);
1750 while ( ! i_ring_empty (&fd_w))
1752 int fd = i_ring_pop (&fd_w);
1755 int parent_fd = openat (cwd_fd, "..", O_SEARCH | O_NOATIME);
1761 if (!same_fd (fd, parent_fd))
1763 char *cwd = getcwdat (fd, NULL, 0);
1764 error (0, errno, "ring : %s", cwd);
1765 char *c2 = getcwdat (parent_fd, NULL, 0);
1766 error (0, errno, "parent: %s", c2);
1779 static unsigned short int
1781 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1783 struct stat *sbp = p->fts_statp;
1786 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1790 * If doing a logical walk, or application requested FTS_FOLLOW, do
1791 * a stat(2). If that fails, check for a non-existent symlink. If
1792 * fail, set the errno from the stat call.
1794 if (ISSET(FTS_LOGICAL) || follow) {
1795 if (stat(p->fts_accpath, sbp)) {
1796 saved_errno = errno;
1798 && lstat(p->fts_accpath, sbp) == 0) {
1800 return (FTS_SLNONE);
1802 p->fts_errno = saved_errno;
1805 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1806 AT_SYMLINK_NOFOLLOW)) {
1807 p->fts_errno = errno;
1808 err: memset(sbp, 0, sizeof(struct stat));
1812 if (S_ISDIR(sbp->st_mode)) {
1813 p->fts_n_dirs_remaining = (sbp->st_nlink
1814 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1815 if (ISDOT(p->fts_name)) {
1816 /* Command-line "." and ".." are real directories. */
1817 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1822 if (S_ISLNK(sbp->st_mode))
1824 if (S_ISREG(sbp->st_mode))
1826 return (FTS_DEFAULT);
1830 fts_compar (void const *a, void const *b)
1832 /* Convert A and B to the correct types, to pacify the compiler, and
1833 for portability to bizarre hosts where "void const *" and "FTSENT
1834 const **" differ in runtime representation. The comparison
1835 function cannot modify *a and *b, but there is no compile-time
1837 FTSENT const **pa = (FTSENT const **) a;
1838 FTSENT const **pb = (FTSENT const **) b;
1839 return pa[0]->fts_fts->fts_compar (pa, pb);
1844 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1846 register FTSENT **ap, *p;
1848 /* On most modern hosts, void * and FTSENT ** have the same
1849 run-time representation, and one can convert sp->fts_compar to
1850 the type qsort expects without problem. Use the heuristic that
1851 this is OK if the two pointer types are the same size, and if
1852 converting FTSENT ** to long int is the same as converting
1853 FTSENT ** to void * and then to long int. This heuristic isn't
1854 valid in general but we don't know of any counterexamples. */
1856 int (*compare) (void const *, void const *) =
1857 ((sizeof &dummy == sizeof (void *)
1858 && (long int) &dummy == (long int) (void *) &dummy)
1859 ? (int (*) (void const *, void const *)) sp->fts_compar
1863 * Construct an array of pointers to the structures and call qsort(3).
1864 * Reassemble the array in the order returned by qsort. If unable to
1865 * sort for memory reasons, return the directory entries in their
1866 * current order. Allocate enough space for the current needs plus
1867 * 40 so don't realloc one entry at a time.
1869 if (nitems > sp->fts_nitems) {
1872 sp->fts_nitems = nitems + 40;
1873 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1874 || ! (a = realloc (sp->fts_array,
1875 sp->fts_nitems * sizeof *a))) {
1876 free(sp->fts_array);
1877 sp->fts_array = NULL;
1883 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1885 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1886 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1887 ap[0]->fts_link = ap[1];
1888 ap[0]->fts_link = NULL;
1894 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1900 * The file name is a variable length array. Allocate the FTSENT
1901 * structure and the file name in one chunk.
1903 len = sizeof(FTSENT) + namelen;
1904 if ((p = malloc(len)) == NULL)
1907 /* Copy the name and guarantee NUL termination. */
1908 memcpy(p->fts_name, name, namelen);
1909 p->fts_name[namelen] = '\0';
1911 p->fts_namelen = namelen;
1913 p->fts_path = sp->fts_path;
1917 p->fts_instr = FTS_NOINSTR;
1919 p->fts_pointer = NULL;
1925 fts_lfree (register FTSENT *head)
1929 /* Free a linked list of structures. */
1930 while ((p = head)) {
1931 head = head->fts_link;
1933 closedir (p->fts_dirp);
1939 * Allow essentially unlimited file name lengths; find, rm, ls should
1940 * all work on any tree. Most systems will allow creation of file
1941 * names much longer than MAXPATHLEN, even though the kernel won't
1942 * resolve them. Add the size (not just what's needed) plus 256 bytes
1943 * so don't realloc the file name 2 bytes at a time.
1947 fts_palloc (FTS *sp, size_t more)
1950 size_t new_len = sp->fts_pathlen + more + 256;
1953 * See if fts_pathlen would overflow.
1955 if (new_len < sp->fts_pathlen) {
1957 sp->fts_path = NULL;
1958 __set_errno (ENAMETOOLONG);
1961 sp->fts_pathlen = new_len;
1962 p = realloc(sp->fts_path, sp->fts_pathlen);
1965 sp->fts_path = NULL;
1973 * When the file name is realloc'd, have to fix all of the pointers in
1974 * structures already returned.
1978 fts_padjust (FTS *sp, FTSENT *head)
1981 char *addr = sp->fts_path;
1983 #define ADJUST(p) do { \
1984 if ((p)->fts_accpath != (p)->fts_name) { \
1985 (p)->fts_accpath = \
1986 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1988 (p)->fts_path = addr; \
1990 /* Adjust the current set of children. */
1991 for (p = sp->fts_child; p; p = p->fts_link)
1994 /* Adjust the rest of the tree, including the current level. */
1995 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1997 p = p->fts_link ? p->fts_link : p->fts_parent;
2002 internal_function _GL_ATTRIBUTE_PURE
2003 fts_maxarglen (char * const *argv)
2007 for (max = 0; *argv; ++argv)
2008 if ((len = strlen(*argv)) > max)
2014 * Change to dir specified by fd or file name without getting
2015 * tricked by someone changing the world out from underneath us.
2016 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
2017 * If FD is non-negative, expect it to be used after this function returns,
2018 * and to be closed eventually. So don't pass e.g., 'dirfd(dirp)' and then
2019 * do closedir(dirp), because that would invalidate the saved FD.
2020 * Upon failure, close FD immediately and return nonzero.
2024 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
2027 bool is_dotdot = dir && STREQ (dir, "..");
2030 /* This clause handles the unusual case in which FTS_NOCHDIR
2031 is specified, along with FTS_CWDFD. In that case, there is
2032 no need to change even the virtual cwd file descriptor.
2033 However, if FD is non-negative, we do close it here. */
2034 if (ISSET (FTS_NOCHDIR))
2036 if (ISSET (FTS_CWDFD) && 0 <= fd)
2041 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
2043 /* When possible, skip the diropen and subsequent fstat+dev/ino
2044 comparison. I.e., when changing to parent directory
2045 (chdir ("..")), use a file descriptor from the ring and
2046 save the overhead of diropen+fstat, as well as avoiding
2047 failure when we lack "x" access to the virtual cwd. */
2048 if ( ! i_ring_empty (&sp->fts_fd_ring))
2051 fd_ring_print (sp, stderr, "pre-pop");
2052 parent_fd = i_ring_pop (&sp->fts_fd_ring);
2063 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
2066 /* The following dev/inode check is necessary if we're doing a
2067 "logical" traversal (through symlinks, a la chown -L), if the
2068 system lacks O_NOFOLLOW support, or if we're changing to ".."
2069 (but not via a popped file descriptor). When changing to the
2070 name "..", O_NOFOLLOW can't help. In general, when the target is
2071 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
2072 follow a symlink, so we can avoid the expense of this fstat. */
2073 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
2074 || (dir && STREQ (dir, "..")))
2077 if (fstat(newfd, &sb))
2082 if (p->fts_statp->st_dev != sb.st_dev
2083 || p->fts_statp->st_ino != sb.st_ino)
2085 __set_errno (ENOENT); /* disinformation */
2091 if (ISSET(FTS_CWDFD))
2093 cwd_advance_fd (sp, newfd, ! is_dotdot);
2097 ret = fchdir(newfd);
2103 __set_errno (oerrno);