1 /* Traverse a file hierarchy.
3 Copyright (C) 2004-2009 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 * Copyright (c) 1990, 1993, 1994
20 * The Regents of the University of California. All rights reserved.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the above copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 4. Neither the name of the University nor the names of its contributors
31 * may be used to endorse or promote products derived from this software
32 * without specific prior written permission.
34 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
35 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
36 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
37 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
38 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
39 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
40 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
41 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
42 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
43 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
49 #if defined(LIBC_SCCS) && !defined(lint)
50 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
51 #endif /* LIBC_SCCS and not lint */
55 #if HAVE_SYS_PARAM_H || defined _LIBC
56 # include <sys/param.h>
59 # include <include/sys/stat.h>
61 # include <sys/stat.h>
73 # include "unistd--.h"
74 # include "same-inode.h"
78 #ifndef _D_EXACT_NAMLEN
79 # define _D_EXACT_NAMLEN(dirent) strlen ((dirent)->d_name)
82 #if HAVE_STRUCT_DIRENT_D_TYPE
83 /* True if the type of the directory entry D is known. */
84 # define DT_IS_KNOWN(d) ((d)->d_type != DT_UNKNOWN)
85 /* True if the type of the directory entry D must be T. */
86 # define DT_MUST_BE(d, t) ((d)->d_type == (t))
87 # define D_TYPE(d) ((d)->d_type)
89 # define DT_IS_KNOWN(d) false
90 # define DT_MUST_BE(d, t) false
91 # define D_TYPE(d) DT_UNKNOWN
96 /* Any nonzero values will do here, so long as they're distinct.
97 Undef any existing macros out of the way. */
123 NOT_AN_INODE_NUMBER = 0
126 #ifdef D_INO_IN_DIRENT
127 # define D_INO(dp) (dp)->d_ino
129 /* Some systems don't have inodes, so fake them to avoid lots of ifdefs. */
130 # define D_INO(dp) NOT_AN_INODE_NUMBER
133 /* If there are more than this many entries in a directory,
134 and the conditions mentioned below are satisfied, then sort
135 the entries on inode number before any further processing. */
136 #ifndef FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
137 # define FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD 10000
141 _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD = FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
146 FTS_NO_STAT_REQUIRED = 1,
147 FTS_STAT_REQUIRED = 2
152 # define close __close
154 # define closedir __closedir
156 # define fchdir __fchdir
160 # define opendir __opendir
162 # define readdir __readdir
164 # undef internal_function
165 # define internal_function /* empty */
169 # define __set_errno(Val) errno = (Val)
172 #ifndef __attribute__
173 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
174 # define __attribute__(x) /* empty */
178 #ifndef ATTRIBUTE_UNUSED
179 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
182 /* If this host provides the openat function, then we can avoid
183 attempting to open "." in some initialization code below. */
185 # define HAVE_OPENAT_SUPPORT 1
187 # define HAVE_OPENAT_SUPPORT 0
191 # define fts_assert(expr) ((void) 0)
193 # define fts_assert(expr) \
202 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
203 static FTSENT *fts_build (FTS *, int) internal_function;
204 static void fts_lfree (FTSENT *) internal_function;
205 static void fts_load (FTS *, FTSENT *) internal_function;
206 static size_t fts_maxarglen (char * const *) internal_function;
207 static void fts_padjust (FTS *, FTSENT *) internal_function;
208 static bool fts_palloc (FTS *, size_t) internal_function;
209 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
210 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
211 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
215 # include "fts-cycle.c"
217 static bool enter_dir (FTS *fts, FTSENT *ent) { return true; }
218 static void leave_dir (FTS *fts, FTSENT *ent) {}
219 static bool setup_dir (FTS *fts) { return true; }
220 static void free_dir (FTS *fts) {}
224 # define MAX(a,b) ((a) > (b) ? (a) : (b))
228 # define SIZE_MAX ((size_t) -1)
232 # define O_DIRECTORY 0
235 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
236 #define STREQ(a, b) (strcmp ((a), (b)) == 0)
238 #define CLR(opt) (sp->fts_options &= ~(opt))
239 #define ISSET(opt) (sp->fts_options & (opt))
240 #define SET(opt) (sp->fts_options |= (opt))
242 /* FIXME: make this a function */
243 #define RESTORE_INITIAL_CWD(sp) \
244 (fd_ring_clear (&((sp)->fts_fd_ring)), \
245 FCHDIR ((sp), (ISSET (FTS_CWDFD) ? AT_FDCWD : (sp)->fts_rfd)))
247 /* FIXME: FTS_NOCHDIR is now misnamed.
248 Call it FTS_USE_FULL_RELATIVE_FILE_NAMES instead. */
249 #define FCHDIR(sp, fd) \
250 (!ISSET(FTS_NOCHDIR) && (ISSET(FTS_CWDFD) \
251 ? (cwd_advance_fd ((sp), (fd), true), 0) \
255 /* fts_build flags */
256 /* FIXME: make this an enum */
257 #define BCHILD 1 /* fts_children */
258 #define BNAMES 2 /* fts_children, names only */
259 #define BREAD 3 /* fts_read */
262 # include <inttypes.h>
265 # include "getcwdat.h"
266 bool fts_debug = false;
267 # define Dprintf(x) do { if (fts_debug) printf x; } while (false)
270 # define fd_ring_check(x)
271 # define fd_ring_print(a, b, c)
274 #define LEAVE_DIR(Fts, Ent, Tag) \
277 Dprintf ((" %s-leaving: %s\n", Tag, (Ent)->fts_path)); \
278 leave_dir (Fts, Ent); \
279 fd_ring_check (Fts); \
284 fd_ring_clear (I_ring *fd_ring)
286 while ( ! i_ring_empty (fd_ring))
288 int fd = i_ring_pop (fd_ring);
294 /* Overload the fts_statp->st_size member (otherwise unused, when
295 fts_info is FTS_NSOK) to indicate whether fts_read should stat
296 this entry or not. */
298 fts_set_stat_required (FTSENT *p, bool required)
300 fts_assert (p->fts_info == FTS_NSOK);
301 p->fts_statp->st_size = (required
303 : FTS_NO_STAT_REQUIRED);
306 /* file-descriptor-relative opendir. */
307 /* FIXME: if others need this function, move it into lib/openat.c */
310 opendirat (int fd, char const *dir)
312 int new_fd = openat (fd, dir, O_RDONLY);
317 dirp = fdopendir (new_fd);
320 int saved_errno = errno;
327 /* Virtual fchdir. Advance SP's working directory file descriptor,
328 SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
329 CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory
330 open on sp->fts_cwd_fd; i.e., to move the working directory one level
334 cwd_advance_fd (FTS *sp, int fd, bool chdir_down_one)
336 int old = sp->fts_cwd_fd;
337 fts_assert (old != fd || old == AT_FDCWD);
341 /* Push "old" onto the ring.
342 If the displaced file descriptor is non-negative, close it. */
343 int prev_fd_in_slot = i_ring_push (&sp->fts_fd_ring, old);
344 fd_ring_print (sp, stderr, "post-push");
345 if (0 <= prev_fd_in_slot)
346 close (prev_fd_in_slot); /* ignore any close failure */
348 else if ( ! ISSET (FTS_NOCHDIR))
351 close (old); /* ignore any close failure */
357 /* Open the directory DIR if possible, and return a file
358 descriptor. Return -1 and set errno on failure. It doesn't matter
359 whether the file descriptor has read or write access. */
363 diropen (FTS const *sp, char const *dir)
365 int open_flags = (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
366 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0));
368 return (ISSET (FTS_CWDFD)
369 ? openat (sp->fts_cwd_fd, dir, open_flags)
370 : open (dir, open_flags));
374 fts_open (char * const *argv,
375 register int options,
376 int (*compar) (FTSENT const **, FTSENT const **))
379 register FTSENT *p, *root;
380 register size_t nitems;
381 FTSENT *parent = NULL;
382 FTSENT *tmp = NULL; /* pacify gcc */
387 if (options & ~FTS_OPTIONMASK) {
388 __set_errno (EINVAL);
391 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
392 __set_errno (EINVAL);
395 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
396 __set_errno (EINVAL);
400 /* Allocate/initialize the stream */
401 if ((sp = malloc(sizeof(FTS))) == NULL)
403 memset(sp, 0, sizeof(FTS));
404 sp->fts_compar = compar;
405 sp->fts_options = options;
407 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
408 if (ISSET(FTS_LOGICAL)) {
413 /* Initialize fts_cwd_fd. */
414 sp->fts_cwd_fd = AT_FDCWD;
415 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
417 /* While it isn't technically necessary to open "." this
418 early, doing it here saves us the trouble of ensuring
419 later (where it'd be messier) that "." can in fact
420 be opened. If not, revert to FTS_NOCHDIR mode. */
421 int fd = open (".", O_RDONLY);
424 /* Even if `.' is unreadable, don't revert to FTS_NOCHDIR mode
425 on systems like Linux+PROC_FS, where our openat emulation
426 is good enough. Note: on a system that emulates
427 openat via /proc, this technique can still fail, but
428 only in extreme conditions, e.g., when the working
429 directory cannot be saved (i.e. save_cwd fails) --
430 and that happens on Linux only when "." is unreadable
431 and the CWD would be longer than PATH_MAX.
432 FIXME: once Linux kernel openat support is well established,
433 replace the above open call and this entire if/else block
434 with the body of the if-block below. */
435 if ( openat_needs_fchdir ())
448 * Start out with 1K of file name space, and enough, in any case,
449 * to hold the user's file names.
452 # define MAXPATHLEN 1024
455 size_t maxarglen = fts_maxarglen(argv);
456 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
460 /* Allocate/initialize root's parent. */
462 if ((parent = fts_alloc(sp, "", 0)) == NULL)
464 parent->fts_level = FTS_ROOTPARENTLEVEL;
467 /* The classic fts implementation would call fts_stat with
468 a new entry for each iteration of the loop below.
469 If the comparison function is not specified or if the
470 FTS_DEFER_STAT option is in effect, don't stat any entry
471 in this loop. This is an attempt to minimize the interval
472 between the initial stat/lstat/fstatat and the point at which
473 a directory argument is first opened. This matters for any
474 directory command line argument that resides on a file system
475 without genuine i-nodes. If you specify FTS_DEFER_STAT along
476 with a comparison function, that function must not access any
477 data via the fts_statp pointer. */
478 defer_stat = (compar == NULL || ISSET(FTS_DEFER_STAT));
480 /* Allocate/initialize root(s). */
481 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
482 /* Don't allow zero-length file names. */
483 if ((len = strlen(*argv)) == 0) {
484 __set_errno (ENOENT);
488 if ((p = fts_alloc(sp, *argv, len)) == NULL)
490 p->fts_level = FTS_ROOTLEVEL;
491 p->fts_parent = parent;
492 p->fts_accpath = p->fts_name;
493 /* Even when defer_stat is true, be sure to stat the first
494 command line argument, since fts_read (at least with
495 FTS_XDEV) requires that. */
496 if (defer_stat && root != NULL) {
497 p->fts_info = FTS_NSOK;
498 fts_set_stat_required(p, true);
500 p->fts_info = fts_stat(sp, p, false);
504 * If comparison routine supplied, traverse in sorted
505 * order; otherwise traverse in the order specified.
520 if (compar && nitems > 1)
521 root = fts_sort(sp, root, nitems);
524 * Allocate a dummy pointer and make fts_read think that we've just
525 * finished the node before the root(s); set p->fts_info to FTS_INIT
526 * so that everything about the "current" node is ignored.
528 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
530 sp->fts_cur->fts_link = root;
531 sp->fts_cur->fts_info = FTS_INIT;
532 if (! setup_dir (sp))
536 * If using chdir(2), grab a file descriptor pointing to dot to ensure
537 * that we can get back here; this could be avoided for some file names,
538 * but almost certainly not worth the effort. Slashes, symbolic links,
539 * and ".." are all fairly nasty problems. Note, if we can't get the
540 * descriptor we run anyway, just more slowly.
542 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
543 && (sp->fts_rfd = diropen (sp, ".")) < 0)
546 i_ring_init (&sp->fts_fd_ring, -1);
549 mem3: fts_lfree(root);
551 mem2: free(sp->fts_path);
558 fts_load (FTS *sp, register FTSENT *p)
564 * Load the stream structure for the next traversal. Since we don't
565 * actually enter the directory until after the preorder visit, set
566 * the fts_accpath field specially so the chdir gets done to the right
567 * place and the user can access the first node. From fts_open it's
568 * known that the file name will fit.
570 len = p->fts_pathlen = p->fts_namelen;
571 memmove(sp->fts_path, p->fts_name, len + 1);
572 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
574 memmove(p->fts_name, cp, len + 1);
575 p->fts_namelen = len;
577 p->fts_accpath = p->fts_path = sp->fts_path;
583 register FTSENT *freep, *p;
587 * This still works if we haven't read anything -- the dummy structure
588 * points to the root list, so we step through to the end of the root
589 * list which has a valid parent pointer.
592 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
594 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
600 /* Free up child linked list, sort array, file name buffer. */
602 fts_lfree(sp->fts_child);
606 if (ISSET(FTS_CWDFD))
608 if (0 <= sp->fts_cwd_fd)
609 close (sp->fts_cwd_fd);
611 else if (!ISSET(FTS_NOCHDIR))
613 /* Return to original directory, save errno if necessary. */
614 if (fchdir(sp->fts_rfd))
619 fd_ring_clear (&sp->fts_fd_ring);
621 if (sp->fts_leaf_optimization_works_ht)
622 hash_free (sp->fts_leaf_optimization_works_ht);
626 /* Free up the stream pointer. */
629 /* Set errno and return. */
631 __set_errno (saved_errno);
638 #if defined __linux__ \
639 && HAVE_SYS_VFS_H && HAVE_FSTATFS && HAVE_STRUCT_STATFS_F_TYPE
643 /* Linux-specific constants from coreutils' src/fs.h */
644 # define S_MAGIC_TMPFS 0x1021994
645 # define S_MAGIC_NFS 0x6969
646 # define S_MAGIC_REISERFS 0x52654973
647 # define S_MAGIC_PROC 0x9FA0
649 /* Return false if it is easy to determine the file system type of
650 the directory on which DIR_FD is open, and sorting dirents on
651 inode numbers is known not to improve traversal performance with
652 that type of file system. Otherwise, return true. */
654 dirent_inode_sort_may_be_useful (int dir_fd)
656 /* Skip the sort only if we can determine efficiently
657 that skipping it is the right thing to do.
658 The cost of performing an unnecessary sort is negligible,
659 while the cost of *not* performing it can be O(N^2) with
660 a very large constant. */
661 struct statfs fs_buf;
663 /* If fstatfs fails, assume sorting would be useful. */
664 if (fstatfs (dir_fd, &fs_buf) != 0)
667 /* FIXME: what about when f_type is not an integral type?
668 deal with that if/when it's encountered. */
669 switch (fs_buf.f_type)
673 /* On a file system of any of these types, sorting
674 is unnecessary, and hence wasteful. */
682 /* Given a file descriptor DIR_FD open on a directory D,
683 return true if it is valid to apply the leaf-optimization
684 technique of counting directories in D via stat.st_nlink. */
686 leaf_optimization_applies (int dir_fd)
688 struct statfs fs_buf;
690 /* If fstatfs fails, assume we can't use the optimization. */
691 if (fstatfs (dir_fd, &fs_buf) != 0)
694 /* FIXME: do we need to detect AFS mount points? I doubt it,
695 unless fstatfs can report S_MAGIC_REISERFS for such a directory. */
697 switch (fs_buf.f_type)
699 /* List here the file system types that lack useable dirent.d_type
700 info, yet for which the optimization does apply. */
701 case S_MAGIC_REISERFS:
705 /* Explicitly listing this or any other file system type for which
706 the optimization is not applicable is not necessary, but we leave
707 it here to document the risk. Per http://bugs.debian.org/143111,
708 /proc may have bogus stat.st_nlink values. */
716 static bool dirent_inode_sort_may_be_useful (int dir_fd) { return true; }
717 static bool leaf_optimization_applies (int dir_fd) { return false; }
720 /* link-count-optimization entry:
721 map an stat.st_dev number to a boolean: leaf_optimization_works */
728 /* Use a tiny initial size. If a traversal encounters more than
729 a few devices, the cost of growing/rehashing this table will be
730 rendered negligible by the number of inodes processed. */
731 enum { LCO_HT_INITIAL_SIZE = 13 };
734 LCO_hash (void const *x, size_t table_size)
736 struct LCO_ent const *ax = x;
737 return (uintmax_t) ax->st_dev % table_size;
741 LCO_compare (void const *x, void const *y)
743 struct LCO_ent const *ax = x;
744 struct LCO_ent const *ay = y;
745 return ax->st_dev == ay->st_dev;
748 /* Ask the same question as leaf_optimization_applies, but query
749 the cache first (FTS.fts_leaf_optimization_works_ht), and if necessary,
750 update that cache. */
752 link_count_optimize_ok (FTSENT const *p)
754 FTS *sp = p->fts_fts;
755 Hash_table *h = sp->fts_leaf_optimization_works_ht;
761 /* If we're not in CWDFD mode, don't bother with this optimization,
762 since the caller is not serious about performance. */
763 if (!ISSET(FTS_CWDFD))
766 /* map st_dev to the boolean, leaf_optimization_works */
769 h = sp->fts_leaf_optimization_works_ht
770 = hash_initialize (LCO_HT_INITIAL_SIZE, NULL, LCO_hash,
775 tmp.st_dev = p->fts_statp->st_dev;
776 ent = hash_lookup (h, &tmp);
780 /* Look-up failed. Query directly and cache the result. */
781 t2 = malloc (sizeof *t2);
785 /* Is it ok to perform the optimization in the dir, FTS_CWD_FD? */
786 opt_ok = leaf_optimization_applies (sp->fts_cwd_fd);
788 t2->st_dev = p->fts_statp->st_dev;
790 ent = hash_insert (h, t2);
793 /* insertion failed */
797 fts_assert (ent == t2);
803 * Special case of "/" at the end of the file name so that slashes aren't
804 * appended which would cause file names to be written as "....//foo".
807 (p->fts_path[p->fts_pathlen - 1] == '/' \
808 ? p->fts_pathlen - 1 : p->fts_pathlen)
811 fts_read (register FTS *sp)
813 register FTSENT *p, *tmp;
814 register unsigned short int instr;
817 /* If finished or unrecoverable error, return NULL. */
818 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
821 /* Set current node pointer. */
824 /* Save and zero out user instructions. */
825 instr = p->fts_instr;
826 p->fts_instr = FTS_NOINSTR;
828 /* Any type of file may be re-visited; re-stat and re-turn. */
829 if (instr == FTS_AGAIN) {
830 p->fts_info = fts_stat(sp, p, false);
833 Dprintf (("fts_read: p=%s\n",
834 p->fts_info == FTS_INIT ? "" : p->fts_path));
837 * Following a symlink -- SLNONE test allows application to see
838 * SLNONE and recover. If indirecting through a symlink, have
839 * keep a pointer to current location. If unable to get that
840 * pointer, follow fails.
842 if (instr == FTS_FOLLOW &&
843 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
844 p->fts_info = fts_stat(sp, p, true);
845 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
846 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
847 p->fts_errno = errno;
848 p->fts_info = FTS_ERR;
850 p->fts_flags |= FTS_SYMFOLLOW;
855 /* Directory in pre-order. */
856 if (p->fts_info == FTS_D) {
857 /* If skipped or crossed mount point, do post-order visit. */
858 if (instr == FTS_SKIP ||
859 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
860 if (p->fts_flags & FTS_SYMFOLLOW)
861 (void)close(p->fts_symfd);
863 fts_lfree(sp->fts_child);
864 sp->fts_child = NULL;
866 p->fts_info = FTS_DP;
867 LEAVE_DIR (sp, p, "1");
871 /* Rebuild if only read the names and now traversing. */
872 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
874 fts_lfree(sp->fts_child);
875 sp->fts_child = NULL;
879 * Cd to the subdirectory.
881 * If have already read and now fail to chdir, whack the list
882 * to make the names come out right, and set the parent errno
883 * so the application will eventually get an error condition.
884 * Set the FTS_DONTCHDIR flag so that when we logically change
885 * directories back to the parent we don't do a chdir.
887 * If haven't read do so. If the read fails, fts_build sets
888 * FTS_STOP or the fts_info field of the node.
890 if (sp->fts_child != NULL) {
891 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
892 p->fts_errno = errno;
893 p->fts_flags |= FTS_DONTCHDIR;
894 for (p = sp->fts_child; p != NULL;
897 p->fts_parent->fts_accpath;
899 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
902 /* If fts_build's call to fts_safe_changedir failed
903 because it was not able to fchdir into a
904 subdirectory, tell the caller. */
905 if (p->fts_errno && p->fts_info != FTS_DNR)
906 p->fts_info = FTS_ERR;
907 LEAVE_DIR (sp, p, "2");
911 sp->fts_child = NULL;
915 /* Move to the next node on this level. */
917 if ((p = p->fts_link) != NULL) {
922 * If reached the top, return to the original directory (or
923 * the root of the tree), and load the file names for the next
926 if (p->fts_level == FTS_ROOTLEVEL) {
927 if (RESTORE_INITIAL_CWD(sp)) {
936 * User may have called fts_set on the node. If skipped,
937 * ignore. If followed, get a file descriptor so we can
938 * get back if necessary.
940 if (p->fts_instr == FTS_SKIP)
942 if (p->fts_instr == FTS_FOLLOW) {
943 p->fts_info = fts_stat(sp, p, true);
944 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
945 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
946 p->fts_errno = errno;
947 p->fts_info = FTS_ERR;
949 p->fts_flags |= FTS_SYMFOLLOW;
951 p->fts_instr = FTS_NOINSTR;
954 name: t = sp->fts_path + NAPPEND(p->fts_parent);
956 memmove(t, p->fts_name, p->fts_namelen + 1);
959 if (p->fts_info == FTS_NSOK)
961 if (p->fts_statp->st_size == FTS_STAT_REQUIRED)
963 FTSENT *parent = p->fts_parent;
964 if (parent->fts_n_dirs_remaining == 0
966 && ISSET(FTS_PHYSICAL)
967 && link_count_optimize_ok (parent))
969 /* nothing more needed */
973 p->fts_info = fts_stat(sp, p, false);
974 if (S_ISDIR(p->fts_statp->st_mode))
976 if (parent->fts_n_dirs_remaining)
977 parent->fts_n_dirs_remaining--;
982 fts_assert (p->fts_statp->st_size == FTS_NO_STAT_REQUIRED);
985 if (p->fts_info == FTS_D)
987 /* Now that P->fts_statp is guaranteed to be valid,
988 if this is a command-line directory, record its
989 device number, to be used for FTS_XDEV. */
990 if (p->fts_level == FTS_ROOTLEVEL)
991 sp->fts_dev = p->fts_statp->st_dev;
992 Dprintf ((" entering: %s\n", p->fts_path));
993 if (! enter_dir (sp, p))
995 __set_errno (ENOMEM);
1002 /* Move up to the parent node. */
1003 p = tmp->fts_parent;
1007 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
1009 * Done; free everything up and set errno to 0 so the user
1010 * can distinguish between error and EOF.
1014 return (sp->fts_cur = NULL);
1017 fts_assert (p->fts_info != FTS_NSOK);
1019 /* NUL terminate the file name. */
1020 sp->fts_path[p->fts_pathlen] = '\0';
1023 * Return to the parent directory. If at a root node, restore
1024 * the initial working directory. If we came through a symlink,
1025 * go back through the file descriptor. Otherwise, move up
1026 * one level, via "..".
1028 if (p->fts_level == FTS_ROOTLEVEL) {
1029 if (RESTORE_INITIAL_CWD(sp)) {
1030 p->fts_errno = errno;
1033 } else if (p->fts_flags & FTS_SYMFOLLOW) {
1034 if (FCHDIR(sp, p->fts_symfd)) {
1035 int saved_errno = errno;
1036 (void)close(p->fts_symfd);
1037 __set_errno (saved_errno);
1038 p->fts_errno = errno;
1041 (void)close(p->fts_symfd);
1042 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
1043 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
1044 p->fts_errno = errno;
1047 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
1048 if (p->fts_errno == 0)
1049 LEAVE_DIR (sp, p, "3");
1050 return ISSET(FTS_STOP) ? NULL : p;
1054 * Fts_set takes the stream as an argument although it's not used in this
1055 * implementation; it would be necessary if anyone wanted to add global
1056 * semantics to fts using fts_set. An error return is allowed for similar
1061 fts_set(FTS *sp ATTRIBUTE_UNUSED, FTSENT *p, int instr)
1063 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
1064 instr != FTS_NOINSTR && instr != FTS_SKIP) {
1065 __set_errno (EINVAL);
1068 p->fts_instr = instr;
1073 fts_children (register FTS *sp, int instr)
1078 if (instr != 0 && instr != FTS_NAMEONLY) {
1079 __set_errno (EINVAL);
1083 /* Set current node pointer. */
1087 * Errno set to 0 so user can distinguish empty directory from
1092 /* Fatal errors stop here. */
1093 if (ISSET(FTS_STOP))
1096 /* Return logical hierarchy of user's arguments. */
1097 if (p->fts_info == FTS_INIT)
1098 return (p->fts_link);
1101 * If not a directory being visited in pre-order, stop here. Could
1102 * allow FTS_DNR, assuming the user has fixed the problem, but the
1103 * same effect is available with FTS_AGAIN.
1105 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
1108 /* Free up any previous child list. */
1109 if (sp->fts_child != NULL)
1110 fts_lfree(sp->fts_child);
1112 if (instr == FTS_NAMEONLY) {
1119 * If using chdir on a relative file name and called BEFORE fts_read
1120 * does its chdir to the root of a traversal, we can lose -- we need to
1121 * chdir into the subdirectory, and we don't know where the current
1122 * directory is, so we can't get back so that the upcoming chdir by
1123 * fts_read will work.
1125 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
1127 return (sp->fts_child = fts_build(sp, instr));
1129 if ((fd = diropen (sp, ".")) < 0)
1130 return (sp->fts_child = NULL);
1131 sp->fts_child = fts_build(sp, instr);
1132 if (ISSET(FTS_CWDFD))
1134 cwd_advance_fd (sp, fd, true);
1140 int saved_errno = errno;
1142 __set_errno (saved_errno);
1147 return (sp->fts_child);
1150 /* A comparison function to sort on increasing inode number.
1151 For some file system types, sorting either way makes a huge
1152 performance difference for a directory with very many entries,
1153 but sorting on increasing values is slightly better than sorting
1154 on decreasing values. The difference is in the 5% range. */
1156 fts_compare_ino (struct _ftsent const **a, struct _ftsent const **b)
1158 return (a[0]->fts_statp->st_ino < b[0]->fts_statp->st_ino ? -1
1159 : b[0]->fts_statp->st_ino < a[0]->fts_statp->st_ino ? 1 : 0);
1162 /* Map the dirent.d_type value, DTYPE, to the corresponding stat.st_mode
1163 S_IF* bit and set ST.st_mode, thus clearing all other bits in that field. */
1165 set_stat_type (struct stat *st, unsigned int dtype)
1198 * This is the tricky part -- do not casually change *anything* in here. The
1199 * idea is to build the linked list of entries that are used by fts_children
1200 * and fts_read. There are lots of special cases.
1202 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
1203 * set and it's a physical walk (so that symbolic links can't be directories),
1204 * we can do things quickly. First, if it's a 4.4BSD file system, the type
1205 * of the file is in the directory entry. Otherwise, we assume that the number
1206 * of subdirectories in a node is equal to the number of links to the parent.
1207 * The former skips all stat calls. The latter skips stat calls in any leaf
1208 * directories and for any files after the subdirectories in the directory have
1209 * been found, cutting the stat calls by about 2/3.
1213 fts_build (register FTS *sp, int type)
1215 register struct dirent *dp;
1216 register FTSENT *p, *head;
1217 register size_t nitems;
1227 size_t len, maxlen, new_len;
1230 /* Set current node pointer. */
1234 * Open the directory for reading. If this fails, we're done.
1235 * If being called from fts_read, set the fts_info field.
1237 #if defined FTS_WHITEOUT && 0
1238 if (ISSET(FTS_WHITEOUT))
1239 oflag = DTF_NODUP|DTF_REWIND;
1241 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
1243 # define __opendir2(file, flag) \
1244 ( ! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
1245 ? opendirat(sp->fts_cwd_fd, file) \
1248 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
1249 if (type == BREAD) {
1250 cur->fts_info = FTS_DNR;
1251 cur->fts_errno = errno;
1255 /* Rather than calling fts_stat for each and every entry encountered
1256 in the readdir loop (below), stat each directory only right after
1258 if (cur->fts_info == FTS_NSOK)
1259 cur->fts_info = fts_stat(sp, cur, false);
1262 * Nlinks is the number of possible entries of type directory in the
1263 * directory if we're cheating on stat calls, 0 if we're not doing
1264 * any stat calls at all, (nlink_t) -1 if we're statting everything.
1266 if (type == BNAMES) {
1268 /* Be quiet about nostat, GCC. */
1270 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
1271 nlinks = (cur->fts_statp->st_nlink
1272 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1280 * If we're going to need to stat anything or we want to descend
1281 * and stay in the directory, chdir. If this fails we keep going,
1282 * but set a flag so we don't chdir after the post-order visit.
1283 * We won't be able to stat anything, but we can still return the
1284 * names themselves. Note, that since fts_read won't be able to
1285 * chdir into the directory, it will have to return different file
1286 * names than before, i.e. "a/b" instead of "b". Since the node
1287 * has already been visited in pre-order, have to wait until the
1288 * post-order visit to return the error. There is a special case
1289 * here, if there was nothing to stat then it's not an error to
1290 * not be able to stat. This is all fairly nasty. If a program
1291 * needed sorted entries or stat information, they had better be
1292 * checking FTS_NS on the returned nodes.
1294 if (nlinks || type == BREAD) {
1295 int dir_fd = dirfd(dirp);
1296 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1297 dir_fd = dup (dir_fd);
1298 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1299 if (nlinks && type == BREAD)
1300 cur->fts_errno = errno;
1301 cur->fts_flags |= FTS_DONTCHDIR;
1304 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1313 * Figure out the max file name length that can be stored in the
1314 * current buffer -- the inner loop allocates more space as necessary.
1315 * We really wouldn't have to do the maxlen calculations here, we
1316 * could do them in fts_read before returning the name, but it's a
1317 * lot easier here since the length is part of the dirent structure.
1319 * If not changing directories set a pointer so that can just append
1320 * each new component into the file name.
1323 if (ISSET(FTS_NOCHDIR)) {
1324 cp = sp->fts_path + len;
1327 /* GCC, you're too verbose. */
1331 maxlen = sp->fts_pathlen - len;
1333 level = cur->fts_level + 1;
1335 /* Read the directory, attaching each entry to the `link' pointer. */
1337 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
1340 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1343 if ((p = fts_alloc (sp, dp->d_name,
1344 _D_EXACT_NAMLEN (dp))) == NULL)
1346 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
1347 /* include space for NUL */
1348 oldaddr = sp->fts_path;
1349 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
1351 * No more memory. Save
1352 * errno, free up the current structure and the
1353 * structures already allocated.
1355 mem1: saved_errno = errno;
1359 cur->fts_info = FTS_ERR;
1361 __set_errno (saved_errno);
1364 /* Did realloc() change the pointer? */
1365 if (oldaddr != sp->fts_path) {
1367 if (ISSET(FTS_NOCHDIR))
1368 cp = sp->fts_path + len;
1370 maxlen = sp->fts_pathlen - len;
1373 new_len = len + _D_EXACT_NAMLEN (dp);
1374 if (new_len < len) {
1376 * In the unlikely event that we would end up
1377 * with a file name longer than SIZE_MAX, free up
1378 * the current structure and the structures already
1379 * allocated, then error out with ENAMETOOLONG.
1384 cur->fts_info = FTS_ERR;
1386 __set_errno (ENAMETOOLONG);
1389 p->fts_level = level;
1390 p->fts_parent = sp->fts_cur;
1391 p->fts_pathlen = new_len;
1393 #if defined FTS_WHITEOUT && 0
1394 if (dp->d_type == DT_WHT)
1395 p->fts_flags |= FTS_ISW;
1397 /* Store dirent.d_ino, in case we need to sort
1398 entries before processing them. */
1399 p->fts_statp->st_ino = D_INO (dp);
1401 /* Build a file name for fts_stat to stat. */
1402 if (ISSET(FTS_NOCHDIR)) {
1403 p->fts_accpath = p->fts_path;
1404 memmove(cp, p->fts_name, p->fts_namelen + 1);
1406 p->fts_accpath = p->fts_name;
1408 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1409 /* Record what fts_read will have to do with this
1410 entry. In many cases, it will simply fts_stat it,
1411 but we can take advantage of any d_type information
1412 to optimize away the unnecessary stat calls. I.e.,
1413 if FTS_NOSTAT is in effect and we're not following
1414 symlinks (FTS_PHYSICAL) and d_type indicates this
1415 is *not* a directory, then we won't have to stat it
1416 at all. If it *is* a directory, then (currently)
1417 we stat it regardless, in order to get device and
1418 inode numbers. Some day we might optimize that
1419 away, too, for directories where d_ino is known to
1421 bool skip_stat = (ISSET(FTS_PHYSICAL)
1422 && ISSET(FTS_NOSTAT)
1424 && ! DT_MUST_BE(dp, DT_DIR));
1425 p->fts_info = FTS_NSOK;
1426 /* Propagate dirent.d_type information back
1427 to caller, when possible. */
1428 set_stat_type (p->fts_statp, D_TYPE (dp));
1429 fts_set_stat_required(p, !skip_stat);
1430 is_dir = (ISSET(FTS_PHYSICAL)
1431 && DT_MUST_BE(dp, DT_DIR));
1433 p->fts_info = fts_stat(sp, p, false);
1434 is_dir = (p->fts_info == FTS_D
1435 || p->fts_info == FTS_DC
1436 || p->fts_info == FTS_DOT);
1439 /* Decrement link count if applicable. */
1440 if (nlinks > 0 && is_dir)
1443 /* We walk in directory order so "ls -f" doesn't get upset. */
1457 * If realloc() changed the address of the file name, adjust the
1458 * addresses for the rest of the tree and the dir list.
1461 fts_padjust(sp, head);
1464 * If not changing directories, reset the file name back to original
1467 if (ISSET(FTS_NOCHDIR)) {
1468 if (len == sp->fts_pathlen || nitems == 0)
1474 * If descended after called from fts_children or after called from
1475 * fts_read and nothing found, get back. At the root level we use
1476 * the saved fd; if one of fts_open()'s arguments is a relative name
1477 * to an empty directory, we wind up here with no other way back. If
1478 * can't get back, we're done.
1480 if (descend && (type == BCHILD || !nitems) &&
1481 (cur->fts_level == FTS_ROOTLEVEL
1482 ? RESTORE_INITIAL_CWD(sp)
1483 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1484 cur->fts_info = FTS_ERR;
1490 /* If didn't find anything, return NULL. */
1493 cur->fts_info = FTS_DP;
1498 /* If there are many entries, no sorting function has been specified,
1499 and this file system is of a type that may be slow with a large
1500 number of entries, then sort the directory entries on increasing
1502 if (nitems > _FTS_INODE_SORT_DIR_ENTRIES_THRESHOLD
1504 && ISSET (FTS_CWDFD)
1505 && dirent_inode_sort_may_be_useful (sp->fts_cwd_fd)) {
1506 sp->fts_compar = fts_compare_ino;
1507 head = fts_sort (sp, head, nitems);
1508 sp->fts_compar = NULL;
1511 /* Sort the entries. */
1512 if (sp->fts_compar && nitems > 1)
1513 head = fts_sort(sp, head, nitems);
1519 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1520 current hierarchy. There should be a directory with dev/inode
1521 matching those of AD. If not, print a lot of diagnostics. */
1523 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1526 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1528 if (ad->ino == ent->fts_statp->st_ino
1529 && ad->dev == ent->fts_statp->st_dev)
1532 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1533 printf ("active dirs:\n");
1535 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1536 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1537 ad->fts_ent->fts_accpath,
1538 (uintmax_t) ad->dev,
1539 (uintmax_t) ad->ino,
1541 (uintmax_t) ent->fts_statp->st_dev,
1542 (uintmax_t) ent->fts_statp->st_ino);
1546 fts_cross_check (FTS const *sp)
1548 FTSENT const *ent = sp->fts_cur;
1550 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1553 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1554 /* Make sure every parent dir is in the tree. */
1555 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1557 struct Active_dir ad;
1558 ad.ino = t->fts_statp->st_ino;
1559 ad.dev = t->fts_statp->st_dev;
1560 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1561 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1564 /* Make sure every dir in the tree is an active dir.
1565 But ENT is not necessarily a directory. If so, just skip this part. */
1566 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1567 && (ent->fts_info == FTS_DP
1568 || ent->fts_info == FTS_D))
1570 struct Active_dir *ad;
1571 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1572 ad = hash_get_next (sp->fts_cycle.ht, ad))
1574 find_matching_ancestor (ent, ad);
1580 same_fd (int fd1, int fd2)
1582 struct stat sb1, sb2;
1583 return (fstat (fd1, &sb1) == 0
1584 && fstat (fd2, &sb2) == 0
1585 && SAME_INODE (sb1, sb2));
1589 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1591 I_ring const *fd_ring = &sp->fts_fd_ring;
1592 unsigned int i = fd_ring->fts_front;
1593 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1594 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1596 if (i_ring_empty (fd_ring))
1601 int fd = fd_ring->fts_fd_ring[i];
1603 fprintf (stream, "%d: %d:\n", i, fd);
1606 char *wd = getcwdat (fd, NULL, 0);
1607 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1610 if (i == fd_ring->fts_back)
1612 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1616 /* Ensure that each file descriptor on the fd_ring matches a
1617 parent, grandparent, etc. of the current working directory. */
1619 fd_ring_check (FTS const *sp)
1624 /* Make a writable copy. */
1625 I_ring fd_w = sp->fts_fd_ring;
1627 int cwd_fd = sp->fts_cwd_fd;
1628 cwd_fd = dup (cwd_fd);
1629 char *dot = getcwdat (cwd_fd, NULL, 0);
1630 error (0, 0, "===== check ===== cwd: %s", dot);
1632 while ( ! i_ring_empty (&fd_w))
1634 int fd = i_ring_pop (&fd_w);
1637 int parent_fd = openat (cwd_fd, "..", O_RDONLY);
1643 if (!same_fd (fd, parent_fd))
1645 char *cwd = getcwdat (fd, NULL, 0);
1646 error (0, errno, "ring : %s", cwd);
1647 char *c2 = getcwdat (parent_fd, NULL, 0);
1648 error (0, errno, "parent: %s", c2);
1661 static unsigned short int
1663 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1665 struct stat *sbp = p->fts_statp;
1668 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1671 #if defined FTS_WHITEOUT && 0
1672 /* check for whiteout */
1673 if (p->fts_flags & FTS_ISW) {
1674 memset(sbp, '\0', sizeof (*sbp));
1675 sbp->st_mode = S_IFWHT;
1681 * If doing a logical walk, or application requested FTS_FOLLOW, do
1682 * a stat(2). If that fails, check for a non-existent symlink. If
1683 * fail, set the errno from the stat call.
1685 if (ISSET(FTS_LOGICAL) || follow) {
1686 if (stat(p->fts_accpath, sbp)) {
1687 saved_errno = errno;
1689 && lstat(p->fts_accpath, sbp) == 0) {
1691 return (FTS_SLNONE);
1693 p->fts_errno = saved_errno;
1696 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1697 AT_SYMLINK_NOFOLLOW)) {
1698 p->fts_errno = errno;
1699 err: memset(sbp, 0, sizeof(struct stat));
1703 if (S_ISDIR(sbp->st_mode)) {
1704 p->fts_n_dirs_remaining = (sbp->st_nlink
1705 - (ISSET(FTS_SEEDOT) ? 0 : 2));
1706 if (ISDOT(p->fts_name)) {
1707 /* Command-line "." and ".." are real directories. */
1708 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1714 * Cycle detection is done by brute force when the directory
1715 * is first encountered. If the tree gets deep enough or the
1716 * number of symbolic links to directories is high enough,
1717 * something faster might be worthwhile.
1721 for (t = p->fts_parent;
1722 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1723 if (sbp->st_ino == t->fts_statp->st_ino
1724 && sbp->st_dev == t->fts_statp->st_dev)
1734 if (S_ISLNK(sbp->st_mode))
1736 if (S_ISREG(sbp->st_mode))
1738 return (FTS_DEFAULT);
1742 fts_compar (void const *a, void const *b)
1744 /* Convert A and B to the correct types, to pacify the compiler, and
1745 for portability to bizarre hosts where "void const *" and "FTSENT
1746 const **" differ in runtime representation. The comparison
1747 function cannot modify *a and *b, but there is no compile-time
1749 FTSENT const **pa = (FTSENT const **) a;
1750 FTSENT const **pb = (FTSENT const **) b;
1751 return pa[0]->fts_fts->fts_compar (pa, pb);
1756 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1758 register FTSENT **ap, *p;
1760 /* On most modern hosts, void * and FTSENT ** have the same
1761 run-time representation, and one can convert sp->fts_compar to
1762 the type qsort expects without problem. Use the heuristic that
1763 this is OK if the two pointer types are the same size, and if
1764 converting FTSENT ** to long int is the same as converting
1765 FTSENT ** to void * and then to long int. This heuristic isn't
1766 valid in general but we don't know of any counterexamples. */
1768 int (*compare) (void const *, void const *) =
1769 ((sizeof &dummy == sizeof (void *)
1770 && (long int) &dummy == (long int) (void *) &dummy)
1771 ? (int (*) (void const *, void const *)) sp->fts_compar
1775 * Construct an array of pointers to the structures and call qsort(3).
1776 * Reassemble the array in the order returned by qsort. If unable to
1777 * sort for memory reasons, return the directory entries in their
1778 * current order. Allocate enough space for the current needs plus
1779 * 40 so don't realloc one entry at a time.
1781 if (nitems > sp->fts_nitems) {
1784 sp->fts_nitems = nitems + 40;
1785 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1786 || ! (a = realloc (sp->fts_array,
1787 sp->fts_nitems * sizeof *a))) {
1788 free(sp->fts_array);
1789 sp->fts_array = NULL;
1795 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1797 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1798 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1799 ap[0]->fts_link = ap[1];
1800 ap[0]->fts_link = NULL;
1806 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1812 * The file name is a variable length array. Allocate the FTSENT
1813 * structure and the file name in one chunk.
1815 len = sizeof(FTSENT) + namelen;
1816 if ((p = malloc(len)) == NULL)
1819 /* Copy the name and guarantee NUL termination. */
1820 memmove(p->fts_name, name, namelen);
1821 p->fts_name[namelen] = '\0';
1823 p->fts_namelen = namelen;
1825 p->fts_path = sp->fts_path;
1828 p->fts_instr = FTS_NOINSTR;
1830 p->fts_pointer = NULL;
1836 fts_lfree (register FTSENT *head)
1840 /* Free a linked list of structures. */
1841 while ((p = head)) {
1842 head = head->fts_link;
1848 * Allow essentially unlimited file name lengths; find, rm, ls should
1849 * all work on any tree. Most systems will allow creation of file
1850 * names much longer than MAXPATHLEN, even though the kernel won't
1851 * resolve them. Add the size (not just what's needed) plus 256 bytes
1852 * so don't realloc the file name 2 bytes at a time.
1856 fts_palloc (FTS *sp, size_t more)
1859 size_t new_len = sp->fts_pathlen + more + 256;
1862 * See if fts_pathlen would overflow.
1864 if (new_len < sp->fts_pathlen) {
1866 sp->fts_path = NULL;
1867 __set_errno (ENAMETOOLONG);
1870 sp->fts_pathlen = new_len;
1871 p = realloc(sp->fts_path, sp->fts_pathlen);
1874 sp->fts_path = NULL;
1882 * When the file name is realloc'd, have to fix all of the pointers in
1883 * structures already returned.
1887 fts_padjust (FTS *sp, FTSENT *head)
1890 char *addr = sp->fts_path;
1892 #define ADJUST(p) do { \
1893 if ((p)->fts_accpath != (p)->fts_name) { \
1894 (p)->fts_accpath = \
1895 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1897 (p)->fts_path = addr; \
1899 /* Adjust the current set of children. */
1900 for (p = sp->fts_child; p; p = p->fts_link)
1903 /* Adjust the rest of the tree, including the current level. */
1904 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1906 p = p->fts_link ? p->fts_link : p->fts_parent;
1912 fts_maxarglen (char * const *argv)
1916 for (max = 0; *argv; ++argv)
1917 if ((len = strlen(*argv)) > max)
1923 * Change to dir specified by fd or file name without getting
1924 * tricked by someone changing the world out from underneath us.
1925 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
1926 * If FD is non-negative, expect it to be used after this function returns,
1927 * and to be closed eventually. So don't pass e.g., `dirfd(dirp)' and then
1928 * do closedir(dirp), because that would invalidate the saved FD.
1929 * Upon failure, close FD immediately and return nonzero.
1933 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
1936 bool is_dotdot = dir && STREQ (dir, "..");
1939 /* This clause handles the unusual case in which FTS_NOCHDIR
1940 is specified, along with FTS_CWDFD. In that case, there is
1941 no need to change even the virtual cwd file descriptor.
1942 However, if FD is non-negative, we do close it here. */
1943 if (ISSET (FTS_NOCHDIR))
1945 if (ISSET (FTS_CWDFD) && 0 <= fd)
1950 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
1952 /* When possible, skip the diropen and subsequent fstat+dev/ino
1953 comparison. I.e., when changing to parent directory
1954 (chdir ("..")), use a file descriptor from the ring and
1955 save the overhead of diropen+fstat, as well as avoiding
1956 failure when we lack "x" access to the virtual cwd. */
1957 if ( ! i_ring_empty (&sp->fts_fd_ring))
1960 fd_ring_print (sp, stderr, "pre-pop");
1961 parent_fd = i_ring_pop (&sp->fts_fd_ring);
1972 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
1975 /* The following dev/inode check is necessary if we're doing a
1976 `logical' traversal (through symlinks, a la chown -L), if the
1977 system lacks O_NOFOLLOW support, or if we're changing to ".."
1978 (but not via a popped file descriptor). When changing to the
1979 name "..", O_NOFOLLOW can't help. In general, when the target is
1980 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
1981 follow a symlink, so we can avoid the expense of this fstat. */
1982 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
1983 || (dir && STREQ (dir, "..")))
1986 if (fstat(newfd, &sb))
1991 if (p->fts_statp->st_dev != sb.st_dev
1992 || p->fts_statp->st_ino != sb.st_ino)
1994 __set_errno (ENOENT); /* disinformation */
2000 if (ISSET(FTS_CWDFD))
2002 cwd_advance_fd (sp, newfd, ! is_dotdot);
2006 ret = fchdir(newfd);
2012 __set_errno (oerrno);