1 /* Traverse a file hierarchy.
3 Copyright (C) 2004, 2005, 2006 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 2, or (at your option)
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, write to the Free Software Foundation,
17 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20 * Copyright (c) 1990, 1993, 1994
21 * The Regents of the University of California. All rights reserved.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the above copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 4. Neither the name of the University nor the names of its contributors
32 * may be used to endorse or promote products derived from this software
33 * without specific prior written permission.
35 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
36 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
38 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
39 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
40 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
41 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
42 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
43 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
44 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50 #if defined(LIBC_SCCS) && !defined(lint)
51 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
52 #endif /* LIBC_SCCS and not lint */
56 #if HAVE_SYS_PARAM_H || defined _LIBC
57 # include <sys/param.h>
60 # include <include/sys/stat.h>
62 # include <sys/stat.h>
76 # include "unistd--.h"
77 # include "same-inode.h"
81 #ifndef _D_EXACT_NAMLEN
82 # define _D_EXACT_NAMLEN(dirent) strlen ((dirent)->d_name)
85 #if HAVE_STRUCT_DIRENT_D_TYPE
86 /* True if the type of the directory entry D is known. */
87 # define DT_IS_KNOWN(d) ((d)->d_type != DT_UNKNOWN)
88 /* True if the type of the directory entry D must be T. */
89 # define DT_MUST_BE(d, t) ((d)->d_type == (t))
91 # define DT_IS_KNOWN(d) false
92 # define DT_MUST_BE(d, t) false
97 FTS_NO_STAT_REQUIRED = 1,
103 # define close __close
105 # define closedir __closedir
107 # define fchdir __fchdir
111 # define opendir __opendir
113 # define readdir __readdir
115 # undef internal_function
116 # define internal_function /* empty */
120 # define __set_errno(Val) errno = (Val)
123 #ifndef __attribute__
124 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
125 # define __attribute__(x) /* empty */
129 #ifndef ATTRIBUTE_UNUSED
130 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
133 /* If this host provides the openat function, then we can avoid
134 attempting to open "." in some initialization code below. */
136 # define HAVE_OPENAT_SUPPORT 1
138 # define HAVE_OPENAT_SUPPORT 0
141 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
142 static FTSENT *fts_build (FTS *, int) internal_function;
143 static void fts_lfree (FTSENT *) internal_function;
144 static void fts_load (FTS *, FTSENT *) internal_function;
145 static size_t fts_maxarglen (char * const *) internal_function;
146 static void fts_padjust (FTS *, FTSENT *) internal_function;
147 static bool fts_palloc (FTS *, size_t) internal_function;
148 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
149 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
150 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
154 static bool enter_dir (FTS *fts, FTSENT *ent) { return true; }
155 static void leave_dir (FTS *fts, FTSENT *ent) {}
156 static bool setup_dir (FTS *fts) { return true; }
157 static void free_dir (FTS *fts) {}
159 # include "fts-cycle.c"
163 # define MAX(a,b) ((a) > (b) ? (a) : (b))
167 # define SIZE_MAX ((size_t) -1)
171 # define O_DIRECTORY 0
174 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
175 #define STREQ(a, b) (strcmp ((a), (b)) == 0)
177 #define CLR(opt) (sp->fts_options &= ~(opt))
178 #define ISSET(opt) (sp->fts_options & (opt))
179 #define SET(opt) (sp->fts_options |= (opt))
181 /* FIXME: make this a function */
182 #define RESTORE_INITIAL_CWD(sp) \
183 (fd_ring_clear (&((sp)->fts_fd_ring)), \
184 FCHDIR ((sp), (ISSET (FTS_CWDFD) ? AT_FDCWD : (sp)->fts_rfd)))
186 /* FIXME: FTS_NOCHDIR is now misnamed.
187 Call it FTS_USE_FULL_RELATIVE_FILE_NAMES instead. */
188 #define FCHDIR(sp, fd) \
189 (!ISSET(FTS_NOCHDIR) && (ISSET(FTS_CWDFD) \
190 ? (cwd_advance_fd ((sp), (fd), true), 0) \
194 /* fts_build flags */
195 /* FIXME: make this an enum */
196 #define BCHILD 1 /* fts_children */
197 #define BNAMES 2 /* fts_children, names only */
198 #define BREAD 3 /* fts_read */
201 # include <inttypes.h>
204 # include "getcwdat.h"
205 bool fts_debug = false;
206 # define Dprintf(x) do { if (fts_debug) printf x; } while (false)
209 # define fd_ring_check(x)
210 # define fd_ring_print(a, b, c)
213 #define LEAVE_DIR(Fts, Ent, Tag) \
216 Dprintf ((" %s-leaving: %s\n", Tag, (Ent)->fts_path)); \
217 leave_dir (Fts, Ent); \
218 fd_ring_check (Fts); \
223 fd_ring_clear (I_ring *fd_ring)
225 while ( ! i_ring_empty (fd_ring))
227 int fd = i_ring_pop (fd_ring);
233 /* Overload the fts_statp->st_size member (otherwise unused, when
234 fts_info is FTS_NSOK) to indicate whether fts_read should stat
235 this entry or not. */
237 fts_set_stat_required (FTSENT *p, bool required)
239 if (p->fts_info != FTS_NSOK)
241 p->fts_statp->st_size = (required
243 : FTS_NO_STAT_REQUIRED);
246 /* file-descriptor-relative opendir. */
247 /* FIXME: if others need this function, move it into lib/openat.c */
250 opendirat (int fd, char const *dir)
252 int new_fd = openat (fd, dir, O_RDONLY);
257 dirp = fdopendir (new_fd);
260 int saved_errno = errno;
267 /* Virtual fchdir. Advance SP's working directory file descriptor,
268 SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
269 CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory
270 open on sp->fts_cwd_fd; i.e., to move the working directory one level
274 cwd_advance_fd (FTS *sp, int fd, bool chdir_down_one)
276 int old = sp->fts_cwd_fd;
277 if (old == fd && old != AT_FDCWD)
282 /* Push "old" onto the ring.
283 If the displaced file descriptor is non-negative, close it. */
284 int prev_fd_in_slot = i_ring_push (&sp->fts_fd_ring, old);
285 fd_ring_print (sp, stderr, "post-push");
286 if (0 <= prev_fd_in_slot)
287 close (prev_fd_in_slot); /* ignore any close failure */
289 else if ( ! ISSET (FTS_NOCHDIR))
292 close (old); /* ignore any close failure */
298 /* Open the directory DIR if possible, and return a file
299 descriptor. Return -1 and set errno on failure. It doesn't matter
300 whether the file descriptor has read or write access. */
304 diropen (FTS const *sp, char const *dir)
306 int open_flags = (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
307 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0));
309 return (ISSET (FTS_CWDFD)
310 ? openat (sp->fts_cwd_fd, dir, open_flags)
311 : open (dir, open_flags));
315 fts_open (char * const *argv,
316 register int options,
317 int (*compar) (FTSENT const **, FTSENT const **))
320 register FTSENT *p, *root;
321 register size_t nitems;
322 FTSENT *parent = NULL;
323 FTSENT *tmp = NULL; /* pacify gcc */
328 if (options & ~FTS_OPTIONMASK) {
329 __set_errno (EINVAL);
332 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
333 __set_errno (EINVAL);
336 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
337 __set_errno (EINVAL);
341 /* Allocate/initialize the stream */
342 if ((sp = malloc(sizeof(FTS))) == NULL)
344 memset(sp, 0, sizeof(FTS));
345 sp->fts_compar = compar;
346 sp->fts_options = options;
348 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
349 if (ISSET(FTS_LOGICAL)) {
354 /* Initialize fts_cwd_fd. */
355 sp->fts_cwd_fd = AT_FDCWD;
356 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
358 /* While it isn't technically necessary to open "." this
359 early, doing it here saves us the trouble of ensuring
360 later (where it'd be messier) that "." can in fact
361 be opened. If not, revert to FTS_NOCHDIR mode. */
362 int fd = open (".", O_RDONLY);
365 /* Even if `.' is unreadable, don't revert to FTS_NOCHDIR mode
366 on systems like Linux+PROC_FS, where our openat emulation
367 is good enough. Note: on a system that emulates
368 openat via /proc, this technique can still fail, but
369 only in extreme conditions, e.g., when the working
370 directory cannot be saved (i.e. save_cwd fails) --
371 and that happens on Linux only when "." is unreadable
372 and the CWD would be longer than PATH_MAX.
373 FIXME: once Linux kernel openat support is well established,
374 replace the above open call and this entire if/else block
375 with the body of the if-block below. */
376 if ( openat_needs_fchdir ())
389 * Start out with 1K of file name space, and enough, in any case,
390 * to hold the user's file names.
393 # define MAXPATHLEN 1024
396 size_t maxarglen = fts_maxarglen(argv);
397 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
401 /* Allocate/initialize root's parent. */
403 if ((parent = fts_alloc(sp, "", 0)) == NULL)
405 parent->fts_level = FTS_ROOTPARENTLEVEL;
408 /* The classic fts implementation would call fts_stat with
409 a new entry for each iteration of the loop below.
410 If the comparison function is not specified or if the
411 FTS_DEFER_STAT option is in effect, don't stat any entry
412 in this loop. This is an attempt to minimize the interval
413 between the initial stat/lstat/fstatat and the point at which
414 a directory argument is first opened. This matters for any
415 directory command line argument that resides on a file system
416 without genuine i-nodes. If you specify FTS_DEFER_STAT along
417 with a comparison function, that function must not access any
418 data via the fts_statp pointer. */
419 defer_stat = (compar == NULL || ISSET(FTS_DEFER_STAT));
421 /* Allocate/initialize root(s). */
422 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
423 /* Don't allow zero-length file names. */
424 if ((len = strlen(*argv)) == 0) {
425 __set_errno (ENOENT);
429 if ((p = fts_alloc(sp, *argv, len)) == NULL)
431 p->fts_level = FTS_ROOTLEVEL;
432 p->fts_parent = parent;
433 p->fts_accpath = p->fts_name;
434 /* Even when defer_stat is true, be sure to stat the first
435 command line argument, since fts_read (at least with
436 FTS_XDEV) requires that. */
437 if (defer_stat && root != NULL) {
438 p->fts_info = FTS_NSOK;
439 fts_set_stat_required(p, true);
441 p->fts_info = fts_stat(sp, p, false);
445 * If comparison routine supplied, traverse in sorted
446 * order; otherwise traverse in the order specified.
461 if (compar && nitems > 1)
462 root = fts_sort(sp, root, nitems);
465 * Allocate a dummy pointer and make fts_read think that we've just
466 * finished the node before the root(s); set p->fts_info to FTS_INIT
467 * so that everything about the "current" node is ignored.
469 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
471 sp->fts_cur->fts_link = root;
472 sp->fts_cur->fts_info = FTS_INIT;
473 if (! setup_dir (sp))
477 * If using chdir(2), grab a file descriptor pointing to dot to ensure
478 * that we can get back here; this could be avoided for some file names,
479 * but almost certainly not worth the effort. Slashes, symbolic links,
480 * and ".." are all fairly nasty problems. Note, if we can't get the
481 * descriptor we run anyway, just more slowly.
483 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
484 && (sp->fts_rfd = diropen (sp, ".")) < 0)
487 i_ring_init (&sp->fts_fd_ring, -1);
490 mem3: fts_lfree(root);
492 mem2: free(sp->fts_path);
499 fts_load (FTS *sp, register FTSENT *p)
505 * Load the stream structure for the next traversal. Since we don't
506 * actually enter the directory until after the preorder visit, set
507 * the fts_accpath field specially so the chdir gets done to the right
508 * place and the user can access the first node. From fts_open it's
509 * known that the file name will fit.
511 len = p->fts_pathlen = p->fts_namelen;
512 memmove(sp->fts_path, p->fts_name, len + 1);
513 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
515 memmove(p->fts_name, cp, len + 1);
516 p->fts_namelen = len;
518 p->fts_accpath = p->fts_path = sp->fts_path;
519 sp->fts_dev = p->fts_statp->st_dev;
525 register FTSENT *freep, *p;
529 * This still works if we haven't read anything -- the dummy structure
530 * points to the root list, so we step through to the end of the root
531 * list which has a valid parent pointer.
534 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
536 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
542 /* Free up child linked list, sort array, file name buffer. */
544 fts_lfree(sp->fts_child);
548 if (ISSET(FTS_CWDFD))
550 if (0 <= sp->fts_cwd_fd)
551 close (sp->fts_cwd_fd);
553 else if (!ISSET(FTS_NOCHDIR))
555 /* Return to original directory, save errno if necessary. */
556 if (fchdir(sp->fts_rfd))
561 fd_ring_clear (&sp->fts_fd_ring);
564 /* Free up the stream pointer. */
567 /* Set errno and return. */
569 __set_errno (saved_errno);
577 * Special case of "/" at the end of the file name so that slashes aren't
578 * appended which would cause file names to be written as "....//foo".
581 (p->fts_path[p->fts_pathlen - 1] == '/' \
582 ? p->fts_pathlen - 1 : p->fts_pathlen)
585 fts_read (register FTS *sp)
587 register FTSENT *p, *tmp;
588 register unsigned short int instr;
591 /* If finished or unrecoverable error, return NULL. */
592 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
595 /* Set current node pointer. */
598 /* Save and zero out user instructions. */
599 instr = p->fts_instr;
600 p->fts_instr = FTS_NOINSTR;
602 /* Any type of file may be re-visited; re-stat and re-turn. */
603 if (instr == FTS_AGAIN) {
604 p->fts_info = fts_stat(sp, p, false);
607 Dprintf (("fts_read: p=%s\n",
608 p->fts_info == FTS_INIT ? "" : p->fts_path));
611 * Following a symlink -- SLNONE test allows application to see
612 * SLNONE and recover. If indirecting through a symlink, have
613 * keep a pointer to current location. If unable to get that
614 * pointer, follow fails.
616 if (instr == FTS_FOLLOW &&
617 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
618 p->fts_info = fts_stat(sp, p, true);
619 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
620 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
621 p->fts_errno = errno;
622 p->fts_info = FTS_ERR;
624 p->fts_flags |= FTS_SYMFOLLOW;
629 /* Directory in pre-order. */
630 if (p->fts_info == FTS_D) {
631 /* If skipped or crossed mount point, do post-order visit. */
632 if (instr == FTS_SKIP ||
633 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
634 if (p->fts_flags & FTS_SYMFOLLOW)
635 (void)close(p->fts_symfd);
637 fts_lfree(sp->fts_child);
638 sp->fts_child = NULL;
640 p->fts_info = FTS_DP;
641 LEAVE_DIR (sp, p, "1");
645 /* Rebuild if only read the names and now traversing. */
646 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
648 fts_lfree(sp->fts_child);
649 sp->fts_child = NULL;
653 * Cd to the subdirectory.
655 * If have already read and now fail to chdir, whack the list
656 * to make the names come out right, and set the parent errno
657 * so the application will eventually get an error condition.
658 * Set the FTS_DONTCHDIR flag so that when we logically change
659 * directories back to the parent we don't do a chdir.
661 * If haven't read do so. If the read fails, fts_build sets
662 * FTS_STOP or the fts_info field of the node.
664 if (sp->fts_child != NULL) {
665 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
666 p->fts_errno = errno;
667 p->fts_flags |= FTS_DONTCHDIR;
668 for (p = sp->fts_child; p != NULL;
671 p->fts_parent->fts_accpath;
673 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
676 /* If fts_build's call to fts_safe_changedir failed
677 because it was not able to fchdir into a
678 subdirectory, tell the caller. */
680 p->fts_info = FTS_ERR;
681 LEAVE_DIR (sp, p, "2");
685 sp->fts_child = NULL;
689 /* Move to the next node on this level. */
691 if ((p = p->fts_link) != NULL) {
695 * If reached the top, return to the original directory (or
696 * the root of the tree), and load the file names for the next
699 if (p->fts_level == FTS_ROOTLEVEL) {
700 if (RESTORE_INITIAL_CWD(sp)) {
710 * User may have called fts_set on the node. If skipped,
711 * ignore. If followed, get a file descriptor so we can
712 * get back if necessary.
714 if (p->fts_instr == FTS_SKIP)
716 if (p->fts_instr == FTS_FOLLOW) {
717 p->fts_info = fts_stat(sp, p, true);
718 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
719 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
720 p->fts_errno = errno;
721 p->fts_info = FTS_ERR;
723 p->fts_flags |= FTS_SYMFOLLOW;
725 p->fts_instr = FTS_NOINSTR;
728 name: t = sp->fts_path + NAPPEND(p->fts_parent);
730 memmove(t, p->fts_name, p->fts_namelen + 1);
732 if (p->fts_info == FTS_NSOK)
734 enum Fts_stat need_stat = p->fts_statp->st_size;
737 case FTS_STAT_REQUIRED:
738 p->fts_info = fts_stat(sp, p, false);
740 case FTS_NO_STAT_REQUIRED:
747 if (p->fts_info == FTS_D)
749 Dprintf ((" entering: %s\n", p->fts_path));
750 if (! enter_dir (sp, p))
752 __set_errno (ENOMEM);
759 /* Move up to the parent node. */
763 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
765 * Done; free everything up and set errno to 0 so the user
766 * can distinguish between error and EOF.
770 return (sp->fts_cur = NULL);
773 if (p->fts_info == FTS_NSOK)
776 /* NUL terminate the file name. */
777 sp->fts_path[p->fts_pathlen] = '\0';
780 * Return to the parent directory. If at a root node, restore
781 * the initial working directory. If we came through a symlink,
782 * go back through the file descriptor. Otherwise, move up
783 * one level, via "..".
785 if (p->fts_level == FTS_ROOTLEVEL) {
786 if (RESTORE_INITIAL_CWD(sp)) {
787 p->fts_errno = errno;
790 } else if (p->fts_flags & FTS_SYMFOLLOW) {
791 if (FCHDIR(sp, p->fts_symfd)) {
792 int saved_errno = errno;
793 (void)close(p->fts_symfd);
794 __set_errno (saved_errno);
795 p->fts_errno = errno;
798 (void)close(p->fts_symfd);
799 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
800 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
801 p->fts_errno = errno;
804 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
805 if (p->fts_errno == 0)
806 LEAVE_DIR (sp, p, "3");
808 return ISSET(FTS_STOP) ? NULL : p;
812 * Fts_set takes the stream as an argument although it's not used in this
813 * implementation; it would be necessary if anyone wanted to add global
814 * semantics to fts using fts_set. An error return is allowed for similar
819 fts_set(FTS *sp ATTRIBUTE_UNUSED, FTSENT *p, int instr)
821 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
822 instr != FTS_NOINSTR && instr != FTS_SKIP) {
823 __set_errno (EINVAL);
826 p->fts_instr = instr;
831 fts_children (register FTS *sp, int instr)
836 if (instr != 0 && instr != FTS_NAMEONLY) {
837 __set_errno (EINVAL);
841 /* Set current node pointer. */
845 * Errno set to 0 so user can distinguish empty directory from
850 /* Fatal errors stop here. */
854 /* Return logical hierarchy of user's arguments. */
855 if (p->fts_info == FTS_INIT)
856 return (p->fts_link);
859 * If not a directory being visited in pre-order, stop here. Could
860 * allow FTS_DNR, assuming the user has fixed the problem, but the
861 * same effect is available with FTS_AGAIN.
863 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
866 /* Free up any previous child list. */
867 if (sp->fts_child != NULL)
868 fts_lfree(sp->fts_child);
870 if (instr == FTS_NAMEONLY) {
877 * If using chdir on a relative file name and called BEFORE fts_read
878 * does its chdir to the root of a traversal, we can lose -- we need to
879 * chdir into the subdirectory, and we don't know where the current
880 * directory is, so we can't get back so that the upcoming chdir by
881 * fts_read will work.
883 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
885 return (sp->fts_child = fts_build(sp, instr));
887 if ((fd = diropen (sp, ".")) < 0)
888 return (sp->fts_child = NULL);
889 sp->fts_child = fts_build(sp, instr);
890 if (ISSET(FTS_CWDFD))
892 cwd_advance_fd (sp, fd, true);
898 int saved_errno = errno;
900 __set_errno (saved_errno);
905 return (sp->fts_child);
909 * This is the tricky part -- do not casually change *anything* in here. The
910 * idea is to build the linked list of entries that are used by fts_children
911 * and fts_read. There are lots of special cases.
913 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
914 * set and it's a physical walk (so that symbolic links can't be directories),
915 * we can do things quickly. First, if it's a 4.4BSD file system, the type
916 * of the file is in the directory entry. Otherwise, we assume that the number
917 * of subdirectories in a node is equal to the number of links to the parent.
918 * The former skips all stat calls. The latter skips stat calls in any leaf
919 * directories and for any files after the subdirectories in the directory have
920 * been found, cutting the stat calls by about 2/3.
924 fts_build (register FTS *sp, int type)
926 register struct dirent *dp;
927 register FTSENT *p, *head;
928 register size_t nitems;
938 size_t len, maxlen, new_len;
941 /* Set current node pointer. */
945 * Open the directory for reading. If this fails, we're done.
946 * If being called from fts_read, set the fts_info field.
948 #if defined FTS_WHITEOUT && 0
949 if (ISSET(FTS_WHITEOUT))
950 oflag = DTF_NODUP|DTF_REWIND;
952 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
954 # define __opendir2(file, flag) \
955 ( ! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
956 ? opendirat(sp->fts_cwd_fd, file) \
959 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
961 cur->fts_info = FTS_DNR;
962 cur->fts_errno = errno;
966 /* Rather than calling fts_stat for each and every entry encountered
967 in the readdir loop (below), stat each directory only right after
969 if (cur->fts_info == FTS_NSOK)
970 cur->fts_info = fts_stat(sp, cur, false);
973 * Nlinks is the number of possible entries of type directory in the
974 * directory if we're cheating on stat calls, 0 if we're not doing
975 * any stat calls at all, (nlink_t) -1 if we're statting everything.
977 if (type == BNAMES) {
979 /* Be quiet about nostat, GCC. */
981 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
982 nlinks = (cur->fts_statp->st_nlink
983 - (ISSET(FTS_SEEDOT) ? 0 : 2));
991 * If we're going to need to stat anything or we want to descend
992 * and stay in the directory, chdir. If this fails we keep going,
993 * but set a flag so we don't chdir after the post-order visit.
994 * We won't be able to stat anything, but we can still return the
995 * names themselves. Note, that since fts_read won't be able to
996 * chdir into the directory, it will have to return different file
997 * names than before, i.e. "a/b" instead of "b". Since the node
998 * has already been visited in pre-order, have to wait until the
999 * post-order visit to return the error. There is a special case
1000 * here, if there was nothing to stat then it's not an error to
1001 * not be able to stat. This is all fairly nasty. If a program
1002 * needed sorted entries or stat information, they had better be
1003 * checking FTS_NS on the returned nodes.
1005 if (nlinks || type == BREAD) {
1006 int dir_fd = dirfd(dirp);
1007 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1008 dir_fd = dup (dir_fd);
1009 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
1010 if (nlinks && type == BREAD)
1011 cur->fts_errno = errno;
1012 cur->fts_flags |= FTS_DONTCHDIR;
1015 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
1024 * Figure out the max file name length that can be stored in the
1025 * current buffer -- the inner loop allocates more space as necessary.
1026 * We really wouldn't have to do the maxlen calculations here, we
1027 * could do them in fts_read before returning the name, but it's a
1028 * lot easier here since the length is part of the dirent structure.
1030 * If not changing directories set a pointer so that can just append
1031 * each new component into the file name.
1034 if (ISSET(FTS_NOCHDIR)) {
1035 cp = sp->fts_path + len;
1038 /* GCC, you're too verbose. */
1042 maxlen = sp->fts_pathlen - len;
1044 level = cur->fts_level + 1;
1046 /* Read the directory, attaching each entry to the `link' pointer. */
1048 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
1051 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
1054 if ((p = fts_alloc (sp, dp->d_name,
1055 _D_EXACT_NAMLEN (dp))) == NULL)
1057 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
1058 /* include space for NUL */
1059 oldaddr = sp->fts_path;
1060 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
1062 * No more memory. Save
1063 * errno, free up the current structure and the
1064 * structures already allocated.
1066 mem1: saved_errno = errno;
1070 cur->fts_info = FTS_ERR;
1072 __set_errno (saved_errno);
1075 /* Did realloc() change the pointer? */
1076 if (oldaddr != sp->fts_path) {
1078 if (ISSET(FTS_NOCHDIR))
1079 cp = sp->fts_path + len;
1081 maxlen = sp->fts_pathlen - len;
1084 new_len = len + _D_EXACT_NAMLEN (dp);
1085 if (new_len < len) {
1087 * In the unlikely even that we would end up
1088 * with a file name longer than SIZE_MAX, free up
1089 * the current structure and the structures already
1090 * allocated, then error out with ENAMETOOLONG.
1095 cur->fts_info = FTS_ERR;
1097 __set_errno (ENAMETOOLONG);
1100 p->fts_level = level;
1101 p->fts_parent = sp->fts_cur;
1102 p->fts_pathlen = new_len;
1104 #if defined FTS_WHITEOUT && 0
1105 if (dp->d_type == DT_WHT)
1106 p->fts_flags |= FTS_ISW;
1109 /* Build a file name for fts_stat to stat. */
1110 if (ISSET(FTS_NOCHDIR)) {
1111 p->fts_accpath = p->fts_path;
1112 memmove(cp, p->fts_name, p->fts_namelen + 1);
1114 p->fts_accpath = p->fts_name;
1116 if (sp->fts_compar == NULL || ISSET(FTS_DEFER_STAT)) {
1117 /* Record what fts_read will have to do with this
1118 entry. In many cases, it will simply fts_stat it,
1119 but we can take advantage of any d_type information
1120 to optimize away the unnecessary stat calls. I.e.,
1121 if FTS_NOSTAT is in effect and we're not following
1122 symlinks (FTS_PHYSICAL) and d_type indicates this
1123 is *not* a directory, then we won't have to stat it
1124 at all. If it *is* a directory, then (currently)
1125 we stat it regardless, in order to get device and
1126 inode numbers. Some day we might optimize that
1127 away, too, for directories where d_ino is known to
1129 bool skip_stat = (ISSET(FTS_PHYSICAL)
1130 && ISSET(FTS_NOSTAT)
1132 && ! DT_MUST_BE(dp, DT_DIR));
1133 p->fts_info = FTS_NSOK;
1134 fts_set_stat_required(p, !skip_stat);
1135 is_dir = (ISSET(FTS_PHYSICAL) && ISSET(FTS_NOSTAT)
1136 && DT_MUST_BE(dp, DT_DIR));
1138 p->fts_info = fts_stat(sp, p, false);
1139 is_dir = (p->fts_info == FTS_D
1140 || p->fts_info == FTS_DC
1141 || p->fts_info == FTS_DOT);
1144 /* Decrement link count if applicable. */
1145 if (nlinks > 0 && is_dir)
1148 /* We walk in directory order so "ls -f" doesn't get upset. */
1162 * If realloc() changed the address of the file name, adjust the
1163 * addresses for the rest of the tree and the dir list.
1166 fts_padjust(sp, head);
1169 * If not changing directories, reset the file name back to original
1172 if (ISSET(FTS_NOCHDIR)) {
1173 if (len == sp->fts_pathlen || nitems == 0)
1179 * If descended after called from fts_children or after called from
1180 * fts_read and nothing found, get back. At the root level we use
1181 * the saved fd; if one of fts_open()'s arguments is a relative name
1182 * to an empty directory, we wind up here with no other way back. If
1183 * can't get back, we're done.
1185 if (descend && (type == BCHILD || !nitems) &&
1186 (cur->fts_level == FTS_ROOTLEVEL
1187 ? RESTORE_INITIAL_CWD(sp)
1188 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1189 cur->fts_info = FTS_ERR;
1195 /* If didn't find anything, return NULL. */
1198 cur->fts_info = FTS_DP;
1203 /* Sort the entries. */
1204 if (sp->fts_compar && nitems > 1)
1205 head = fts_sort(sp, head, nitems);
1211 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1212 current hierarchy. There should be a directory with dev/inode
1213 matching those of AD. If not, print a lot of diagnostics. */
1215 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1218 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1220 if (ad->ino == ent->fts_statp->st_ino
1221 && ad->dev == ent->fts_statp->st_dev)
1224 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1225 printf ("active dirs:\n");
1227 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1228 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1229 ad->fts_ent->fts_accpath,
1230 (uintmax_t) ad->dev,
1231 (uintmax_t) ad->ino,
1233 (uintmax_t) ent->fts_statp->st_dev,
1234 (uintmax_t) ent->fts_statp->st_ino);
1238 fts_cross_check (FTS const *sp)
1240 FTSENT const *ent = sp->fts_cur;
1242 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1245 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1246 /* Make sure every parent dir is in the tree. */
1247 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1249 struct Active_dir ad;
1250 ad.ino = t->fts_statp->st_ino;
1251 ad.dev = t->fts_statp->st_dev;
1252 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1253 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1256 /* Make sure every dir in the tree is an active dir.
1257 But ENT is not necessarily a directory. If so, just skip this part. */
1258 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1259 && (ent->fts_info == FTS_DP
1260 || ent->fts_info == FTS_D))
1262 struct Active_dir *ad;
1263 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1264 ad = hash_get_next (sp->fts_cycle.ht, ad))
1266 find_matching_ancestor (ent, ad);
1272 same_fd (int fd1, int fd2)
1274 struct stat sb1, sb2;
1275 return (fstat (fd1, &sb1) == 0
1276 && fstat (fd2, &sb2) == 0
1277 && SAME_INODE (sb1, sb2));
1281 fd_ring_print (FTS const *sp, FILE *stream, char const *msg)
1283 I_ring const *fd_ring = &sp->fts_fd_ring;
1284 unsigned int i = fd_ring->fts_front;
1285 char *cwd = getcwdat (sp->fts_cwd_fd, NULL, 0);
1286 fprintf (stream, "=== %s ========== %s\n", msg, cwd);
1288 if (i_ring_empty (fd_ring))
1293 int fd = fd_ring->fts_fd_ring[i];
1295 fprintf (stream, "%d: %d:\n", i, fd);
1298 char *wd = getcwdat (fd, NULL, 0);
1299 fprintf (stream, "%d: %d: %s\n", i, fd, wd);
1302 if (i == fd_ring->fts_back)
1304 i = (i + I_RING_SIZE - 1) % I_RING_SIZE;
1308 /* Ensure that each file descriptor on the fd_ring matches a
1309 parent, grandparent, etc. of the current working directory. */
1311 fd_ring_check (FTS const *sp)
1316 /* Make a writable copy. */
1317 I_ring fd_w = sp->fts_fd_ring;
1319 int cwd_fd = sp->fts_cwd_fd;
1320 cwd_fd = dup (cwd_fd);
1321 char *dot = getcwdat (cwd_fd, NULL, 0);
1322 error (0, 0, "===== check ===== cwd: %s", dot);
1324 while ( ! i_ring_empty (&fd_w))
1326 int fd = i_ring_pop (&fd_w);
1329 int parent_fd = openat (cwd_fd, "..", O_RDONLY);
1335 if (!same_fd (fd, parent_fd))
1337 char *cwd = getcwdat (fd, NULL, 0);
1338 error (0, errno, "ring : %s", cwd);
1339 char *c2 = getcwdat (parent_fd, NULL, 0);
1340 error (0, errno, "parent: %s", c2);
1353 static unsigned short int
1355 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1357 struct stat *sbp = p->fts_statp;
1360 if (p->fts_level == FTS_ROOTLEVEL && ISSET(FTS_COMFOLLOW))
1363 #if defined FTS_WHITEOUT && 0
1364 /* check for whiteout */
1365 if (p->fts_flags & FTS_ISW) {
1366 memset(sbp, '\0', sizeof (*sbp));
1367 sbp->st_mode = S_IFWHT;
1373 * If doing a logical walk, or application requested FTS_FOLLOW, do
1374 * a stat(2). If that fails, check for a non-existent symlink. If
1375 * fail, set the errno from the stat call.
1377 if (ISSET(FTS_LOGICAL) || follow) {
1378 if (stat(p->fts_accpath, sbp)) {
1379 saved_errno = errno;
1381 && lstat(p->fts_accpath, sbp) == 0) {
1383 return (FTS_SLNONE);
1385 p->fts_errno = saved_errno;
1388 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1389 AT_SYMLINK_NOFOLLOW)) {
1390 p->fts_errno = errno;
1391 err: memset(sbp, 0, sizeof(struct stat));
1395 if (S_ISDIR(sbp->st_mode)) {
1396 if (ISDOT(p->fts_name)) {
1397 /* Command-line "." and ".." are real directories. */
1398 return (p->fts_level == FTS_ROOTLEVEL ? FTS_D : FTS_DOT);
1404 * Cycle detection is done by brute force when the directory
1405 * is first encountered. If the tree gets deep enough or the
1406 * number of symbolic links to directories is high enough,
1407 * something faster might be worthwhile.
1411 for (t = p->fts_parent;
1412 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1413 if (sbp->st_ino == t->fts_statp->st_ino
1414 && sbp->st_dev == t->fts_statp->st_dev)
1424 if (S_ISLNK(sbp->st_mode))
1426 if (S_ISREG(sbp->st_mode))
1428 return (FTS_DEFAULT);
1432 fts_compar (void const *a, void const *b)
1434 /* Convert A and B to the correct types, to pacify the compiler, and
1435 for portability to bizarre hosts where "void const *" and "FTSENT
1436 const **" differ in runtime representation. The comparison
1437 function cannot modify *a and *b, but there is no compile-time
1439 FTSENT const **pa = (FTSENT const **) a;
1440 FTSENT const **pb = (FTSENT const **) b;
1441 return pa[0]->fts_fts->fts_compar (pa, pb);
1446 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1448 register FTSENT **ap, *p;
1450 /* On most modern hosts, void * and FTSENT ** have the same
1451 run-time representation, and one can convert sp->fts_compar to
1452 the type qsort expects without problem. Use the heuristic that
1453 this is OK if the two pointer types are the same size, and if
1454 converting FTSENT ** to long int is the same as converting
1455 FTSENT ** to void * and then to long int. This heuristic isn't
1456 valid in general but we don't know of any counterexamples. */
1458 int (*compare) (void const *, void const *) =
1459 ((sizeof &dummy == sizeof (void *)
1460 && (long int) &dummy == (long int) (void *) &dummy)
1461 ? (int (*) (void const *, void const *)) sp->fts_compar
1465 * Construct an array of pointers to the structures and call qsort(3).
1466 * Reassemble the array in the order returned by qsort. If unable to
1467 * sort for memory reasons, return the directory entries in their
1468 * current order. Allocate enough space for the current needs plus
1469 * 40 so don't realloc one entry at a time.
1471 if (nitems > sp->fts_nitems) {
1474 sp->fts_nitems = nitems + 40;
1475 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1476 || ! (a = realloc (sp->fts_array,
1477 sp->fts_nitems * sizeof *a))) {
1478 free(sp->fts_array);
1479 sp->fts_array = NULL;
1485 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1487 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1488 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1489 ap[0]->fts_link = ap[1];
1490 ap[0]->fts_link = NULL;
1496 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1502 * The file name is a variable length array. Allocate the FTSENT
1503 * structure and the file name in one chunk.
1505 len = sizeof(FTSENT) + namelen;
1506 if ((p = malloc(len)) == NULL)
1509 /* Copy the name and guarantee NUL termination. */
1510 memmove(p->fts_name, name, namelen);
1511 p->fts_name[namelen] = '\0';
1513 p->fts_namelen = namelen;
1515 p->fts_path = sp->fts_path;
1518 p->fts_instr = FTS_NOINSTR;
1520 p->fts_pointer = NULL;
1526 fts_lfree (register FTSENT *head)
1530 /* Free a linked list of structures. */
1531 while ((p = head)) {
1532 head = head->fts_link;
1538 * Allow essentially unlimited file name lengths; find, rm, ls should
1539 * all work on any tree. Most systems will allow creation of file
1540 * names much longer than MAXPATHLEN, even though the kernel won't
1541 * resolve them. Add the size (not just what's needed) plus 256 bytes
1542 * so don't realloc the file name 2 bytes at a time.
1546 fts_palloc (FTS *sp, size_t more)
1549 size_t new_len = sp->fts_pathlen + more + 256;
1552 * See if fts_pathlen would overflow.
1554 if (new_len < sp->fts_pathlen) {
1556 sp->fts_path = NULL;
1557 __set_errno (ENAMETOOLONG);
1560 sp->fts_pathlen = new_len;
1561 p = realloc(sp->fts_path, sp->fts_pathlen);
1564 sp->fts_path = NULL;
1572 * When the file name is realloc'd, have to fix all of the pointers in
1573 * structures already returned.
1577 fts_padjust (FTS *sp, FTSENT *head)
1580 char *addr = sp->fts_path;
1582 #define ADJUST(p) do { \
1583 if ((p)->fts_accpath != (p)->fts_name) { \
1584 (p)->fts_accpath = \
1585 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1587 (p)->fts_path = addr; \
1589 /* Adjust the current set of children. */
1590 for (p = sp->fts_child; p; p = p->fts_link)
1593 /* Adjust the rest of the tree, including the current level. */
1594 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1596 p = p->fts_link ? p->fts_link : p->fts_parent;
1602 fts_maxarglen (char * const *argv)
1606 for (max = 0; *argv; ++argv)
1607 if ((len = strlen(*argv)) > max)
1613 * Change to dir specified by fd or file name without getting
1614 * tricked by someone changing the world out from underneath us.
1615 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
1616 * If FD is non-negative, expect it to be used after this function returns,
1617 * and to be closed eventually. So don't pass e.g., `dirfd(dirp)' and then
1618 * do closedir(dirp), because that would invalidate the saved FD.
1619 * Upon failure, close FD immediately and return nonzero.
1623 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
1626 bool is_dotdot = dir && STREQ (dir, "..");
1629 /* This clause handles the unusual case in which FTS_NOCHDIR
1630 is specified, along with FTS_CWDFD. In that case, there is
1631 no need to change even the virtual cwd file descriptor.
1632 However, if FD is non-negative, we do close it here. */
1633 if (ISSET (FTS_NOCHDIR))
1635 if (ISSET (FTS_CWDFD) && 0 <= fd)
1640 if (fd < 0 && is_dotdot && ISSET (FTS_CWDFD))
1642 /* When possible, skip the diropen and subsequent fstat+dev/ino
1643 comparison. I.e., when changing to parent directory
1644 (chdir ("..")), use a file descriptor from the ring and
1645 save the overhead of diropen+fstat, as well as avoiding
1646 failure when we lack "x" access to the virtual cwd. */
1647 if ( ! i_ring_empty (&sp->fts_fd_ring))
1650 fd_ring_print (sp, stderr, "pre-pop");
1651 parent_fd = i_ring_pop (&sp->fts_fd_ring);
1662 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
1665 /* The following dev/inode check is necessary if we're doing a
1666 `logical' traversal (through symlinks, a la chown -L), if the
1667 system lacks O_NOFOLLOW support, or if we're changing to ".."
1668 (but not via a popped file descriptor). When changing to the
1669 name "..", O_NOFOLLOW can't help. In general, when the target is
1670 not "..", diropen's use of O_NOFOLLOW ensures we don't mistakenly
1671 follow a symlink, so we can avoid the expense of this fstat. */
1672 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
1673 || (dir && STREQ (dir, "..")))
1676 if (fstat(newfd, &sb))
1681 if (p->fts_statp->st_dev != sb.st_dev
1682 || p->fts_statp->st_ino != sb.st_ino)
1684 __set_errno (ENOENT); /* disinformation */
1690 if (ISSET(FTS_CWDFD))
1692 cwd_advance_fd (sp, newfd, ! is_dotdot);
1696 ret = fchdir(newfd);
1702 __set_errno (oerrno);