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"
80 #ifndef _D_EXACT_NAMLEN
81 # define _D_EXACT_NAMLEN(dirent) strlen ((dirent)->d_name)
86 # define close __close
88 # define closedir __closedir
90 # define fchdir __fchdir
94 # define opendir __opendir
96 # define readdir __readdir
98 # undef internal_function
99 # define internal_function /* empty */
103 # define __set_errno(Val) errno = (Val)
106 #ifndef __attribute__
107 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
108 # define __attribute__(x) /* empty */
112 #ifndef ATTRIBUTE_UNUSED
113 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
116 /* If this host provides the openat function, then we can avoid
117 attempting to open "." in some initialization code below. */
119 # define HAVE_OPENAT_SUPPORT 1
121 # define HAVE_OPENAT_SUPPORT 0
124 static FTSENT *fts_alloc (FTS *, const char *, size_t) internal_function;
125 static FTSENT *fts_build (FTS *, int) internal_function;
126 static void fts_lfree (FTSENT *) internal_function;
127 static void fts_load (FTS *, FTSENT *) internal_function;
128 static size_t fts_maxarglen (char * const *) internal_function;
129 static void fts_padjust (FTS *, FTSENT *) internal_function;
130 static bool fts_palloc (FTS *, size_t) internal_function;
131 static FTSENT *fts_sort (FTS *, FTSENT *, size_t) internal_function;
132 static unsigned short int fts_stat (FTS *, FTSENT *, bool) internal_function;
133 static int fts_safe_changedir (FTS *, FTSENT *, int, const char *)
137 static bool enter_dir (FTS *fts, FTSENT *ent) { return true; }
138 static void leave_dir (FTS *fts, FTSENT *ent) {}
139 static bool setup_dir (FTS *fts) { return true; }
140 static void free_dir (FTS *fts) {}
142 # include "fcntl--.h"
143 # include "fts-cycle.c"
147 # define MAX(a,b) ((a) > (b) ? (a) : (b))
151 # define SIZE_MAX ((size_t) -1)
155 # define O_DIRECTORY 0
158 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
159 #define STREQ(a, b) (strcmp ((a), (b)) == 0)
161 #define CLR(opt) (sp->fts_options &= ~(opt))
162 #define ISSET(opt) (sp->fts_options & (opt))
163 #define SET(opt) (sp->fts_options |= (opt))
165 #define RESTORE_INITIAL_CWD(sp) FCHDIR (sp, (ISSET (FTS_CWDFD) \
169 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) \
170 && (ISSET(FTS_CWDFD) \
171 ? (cwd_advance_fd (sp, fd), 0) \
175 /* fts_build flags */
176 #define BCHILD 1 /* fts_children */
177 #define BNAMES 2 /* fts_children, names only */
178 #define BREAD 3 /* fts_read */
181 # include <inttypes.h>
184 bool fts_debug = false;
185 # define Dprintf(x) do { if (fts_debug) printf x; } while (0)
190 #define LEAVE_DIR(Fts, Ent, Tag) \
193 Dprintf ((" %s-leaving: %s\n", Tag, (Ent)->fts_path)); \
194 leave_dir (Fts, Ent); \
198 /* file-descriptor-relative opendir. */
199 /* FIXME: if others need this function, move it into lib/openat.c */
202 opendirat (int fd, char const *dir)
204 int new_fd = openat (fd, dir, O_RDONLY);
209 dirp = fdopendir (new_fd);
212 int saved_errno = errno;
219 /* Virtual fchdir. Advance SP's working directory
220 file descriptor, SP->fts_cwd_fd, to FD, and close
221 the previous one, ignoring any error. */
224 cwd_advance_fd (FTS *sp, int fd)
226 int old = sp->fts_cwd_fd;
227 if (old == fd && old != AT_FDCWD)
231 close (old); /* ignore any close failure */
234 /* Open the directory DIR if possible, and return a file
235 descriptor. Return -1 and set errno on failure. It doesn't matter
236 whether the file descriptor has read or write access. */
240 diropen (FTS const *sp, char const *dir)
242 int open_flags = (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK
243 | (ISSET (FTS_PHYSICAL) ? O_NOFOLLOW : 0));
245 return (ISSET (FTS_CWDFD)
246 ? openat (sp->fts_cwd_fd, dir, open_flags)
247 : open (dir, open_flags));
251 fts_open (char * const *argv,
252 register int options,
253 int (*compar) (FTSENT const **, FTSENT const **))
256 register FTSENT *p, *root;
257 register size_t nitems;
258 FTSENT *parent = NULL;
259 FTSENT *tmp = NULL; /* pacify gcc */
263 if (options & ~FTS_OPTIONMASK) {
264 __set_errno (EINVAL);
267 if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
268 __set_errno (EINVAL);
271 if ( ! (options & (FTS_LOGICAL | FTS_PHYSICAL))) {
272 __set_errno (EINVAL);
276 /* Allocate/initialize the stream */
277 if ((sp = malloc(sizeof(FTS))) == NULL)
279 memset(sp, 0, sizeof(FTS));
280 sp->fts_compar = compar;
281 sp->fts_options = options;
283 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
284 if (ISSET(FTS_LOGICAL)) {
289 /* Initialize fts_cwd_fd. */
290 sp->fts_cwd_fd = AT_FDCWD;
291 if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
293 /* While it isn't technically necessary to open "." this
294 early, doing it here saves us the trouble of ensuring
295 later (where it'd be messier) that "." can in fact
296 be opened. If not, revert to FTS_NOCHDIR mode. */
297 int fd = open (".", O_RDONLY);
300 /* Even if `.' is unreadable, don't revert to FTS_NOCHDIR mode
301 on systems like Linux+PROC_FS, where our openat emulation
302 is good enough. Note: on a system that emulates
303 openat via /proc, this technique can still fail, but
304 only in extreme conditions, e.g., when the working
305 directory cannot be saved (i.e. save_cwd fails) --
306 and that happens on Linux only when "." is unreadable
307 and the CWD would be longer than PATH_MAX.
308 FIXME: once Linux kernel openat support is well established,
309 replace the above open call and this entire if/else block
310 with the body of the if-block below. */
311 if ( openat_needs_fchdir ())
324 * Start out with 1K of file name space, and enough, in any case,
325 * to hold the user's file names.
328 # define MAXPATHLEN 1024
331 size_t maxarglen = fts_maxarglen(argv);
332 if (! fts_palloc(sp, MAX(maxarglen, MAXPATHLEN)))
336 /* Allocate/initialize root's parent. */
338 if ((parent = fts_alloc(sp, "", 0)) == NULL)
340 parent->fts_level = FTS_ROOTPARENTLEVEL;
343 /* Allocate/initialize root(s). */
344 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) {
345 /* Don't allow zero-length file names. */
346 if ((len = strlen(*argv)) == 0) {
347 __set_errno (ENOENT);
351 if ((p = fts_alloc(sp, *argv, len)) == NULL)
353 p->fts_level = FTS_ROOTLEVEL;
354 p->fts_parent = parent;
355 p->fts_accpath = p->fts_name;
356 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW) != 0);
358 /* Command-line "." and ".." are real directories. */
359 if (p->fts_info == FTS_DOT)
363 * If comparison routine supplied, traverse in sorted
364 * order; otherwise traverse in the order specified.
379 if (compar && nitems > 1)
380 root = fts_sort(sp, root, nitems);
383 * Allocate a dummy pointer and make fts_read think that we've just
384 * finished the node before the root(s); set p->fts_info to FTS_INIT
385 * so that everything about the "current" node is ignored.
387 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
389 sp->fts_cur->fts_link = root;
390 sp->fts_cur->fts_info = FTS_INIT;
391 if (! setup_dir (sp))
395 * If using chdir(2), grab a file descriptor pointing to dot to ensure
396 * that we can get back here; this could be avoided for some file names,
397 * but almost certainly not worth the effort. Slashes, symbolic links,
398 * and ".." are all fairly nasty problems. Note, if we can't get the
399 * descriptor we run anyway, just more slowly.
401 if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
402 && (sp->fts_rfd = diropen (sp, ".")) < 0)
407 mem3: fts_lfree(root);
409 mem2: free(sp->fts_path);
416 fts_load (FTS *sp, register FTSENT *p)
422 * Load the stream structure for the next traversal. Since we don't
423 * actually enter the directory until after the preorder visit, set
424 * the fts_accpath field specially so the chdir gets done to the right
425 * place and the user can access the first node. From fts_open it's
426 * known that the file name will fit.
428 len = p->fts_pathlen = p->fts_namelen;
429 memmove(sp->fts_path, p->fts_name, len + 1);
430 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
432 memmove(p->fts_name, cp, len + 1);
433 p->fts_namelen = len;
435 p->fts_accpath = p->fts_path = sp->fts_path;
436 sp->fts_dev = p->fts_statp->st_dev;
442 register FTSENT *freep, *p;
446 * This still works if we haven't read anything -- the dummy structure
447 * points to the root list, so we step through to the end of the root
448 * list which has a valid parent pointer.
451 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
453 p = p->fts_link != NULL ? p->fts_link : p->fts_parent;
459 /* Free up child linked list, sort array, file name buffer. */
461 fts_lfree(sp->fts_child);
465 if (ISSET(FTS_CWDFD))
467 if (0 <= sp->fts_cwd_fd)
468 close (sp->fts_cwd_fd);
470 else if (!ISSET(FTS_NOCHDIR))
472 /* Return to original directory, save errno if necessary. */
473 if (fchdir(sp->fts_rfd))
480 /* Free up the stream pointer. */
483 /* Set errno and return. */
485 __set_errno (saved_errno);
493 * Special case of "/" at the end of the file name so that slashes aren't
494 * appended which would cause file names to be written as "....//foo".
497 (p->fts_path[p->fts_pathlen - 1] == '/' \
498 ? p->fts_pathlen - 1 : p->fts_pathlen)
501 fts_read (register FTS *sp)
503 register FTSENT *p, *tmp;
504 register unsigned short int instr;
507 /* If finished or unrecoverable error, return NULL. */
508 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
511 /* Set current node pointer. */
514 /* Save and zero out user instructions. */
515 instr = p->fts_instr;
516 p->fts_instr = FTS_NOINSTR;
518 /* Any type of file may be re-visited; re-stat and re-turn. */
519 if (instr == FTS_AGAIN) {
520 p->fts_info = fts_stat(sp, p, false);
523 Dprintf (("fts_read: p=%s\n",
524 p->fts_info == FTS_INIT ? "" : p->fts_path));
527 * Following a symlink -- SLNONE test allows application to see
528 * SLNONE and recover. If indirecting through a symlink, have
529 * keep a pointer to current location. If unable to get that
530 * pointer, follow fails.
532 if (instr == FTS_FOLLOW &&
533 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
534 p->fts_info = fts_stat(sp, p, true);
535 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
536 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
537 p->fts_errno = errno;
538 p->fts_info = FTS_ERR;
540 p->fts_flags |= FTS_SYMFOLLOW;
545 /* Directory in pre-order. */
546 if (p->fts_info == FTS_D) {
547 /* If skipped or crossed mount point, do post-order visit. */
548 if (instr == FTS_SKIP ||
549 (ISSET(FTS_XDEV) && p->fts_statp->st_dev != sp->fts_dev)) {
550 if (p->fts_flags & FTS_SYMFOLLOW)
551 (void)close(p->fts_symfd);
553 fts_lfree(sp->fts_child);
554 sp->fts_child = NULL;
556 p->fts_info = FTS_DP;
557 LEAVE_DIR (sp, p, "1");
561 /* Rebuild if only read the names and now traversing. */
562 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) {
564 fts_lfree(sp->fts_child);
565 sp->fts_child = NULL;
569 * Cd to the subdirectory.
571 * If have already read and now fail to chdir, whack the list
572 * to make the names come out right, and set the parent errno
573 * so the application will eventually get an error condition.
574 * Set the FTS_DONTCHDIR flag so that when we logically change
575 * directories back to the parent we don't do a chdir.
577 * If haven't read do so. If the read fails, fts_build sets
578 * FTS_STOP or the fts_info field of the node.
580 if (sp->fts_child != NULL) {
581 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
582 p->fts_errno = errno;
583 p->fts_flags |= FTS_DONTCHDIR;
584 for (p = sp->fts_child; p != NULL;
587 p->fts_parent->fts_accpath;
589 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
592 /* If fts_build's call to fts_safe_changedir failed
593 because it was not able to fchdir into a
594 subdirectory, tell the caller. */
596 p->fts_info = FTS_ERR;
597 LEAVE_DIR (sp, p, "2");
601 sp->fts_child = NULL;
605 /* Move to the next node on this level. */
607 if ((p = p->fts_link) != NULL) {
611 * If reached the top, return to the original directory (or
612 * the root of the tree), and load the file names for the next
615 if (p->fts_level == FTS_ROOTLEVEL) {
616 if (RESTORE_INITIAL_CWD(sp)) {
626 * User may have called fts_set on the node. If skipped,
627 * ignore. If followed, get a file descriptor so we can
628 * get back if necessary.
630 if (p->fts_instr == FTS_SKIP)
632 if (p->fts_instr == FTS_FOLLOW) {
633 p->fts_info = fts_stat(sp, p, true);
634 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
635 if ((p->fts_symfd = diropen (sp, ".")) < 0) {
636 p->fts_errno = errno;
637 p->fts_info = FTS_ERR;
639 p->fts_flags |= FTS_SYMFOLLOW;
641 p->fts_instr = FTS_NOINSTR;
644 name: t = sp->fts_path + NAPPEND(p->fts_parent);
646 memmove(t, p->fts_name, p->fts_namelen + 1);
649 if (p->fts_info == FTS_D)
651 Dprintf ((" %s-entering: %s\n", sp, p->fts_path));
652 if (! enter_dir (sp, p))
654 __set_errno (ENOMEM);
661 /* Move up to the parent node. */
665 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
667 * Done; free everything up and set errno to 0 so the user
668 * can distinguish between error and EOF.
672 return (sp->fts_cur = NULL);
675 /* NUL terminate the file name. */
676 sp->fts_path[p->fts_pathlen] = '\0';
679 * Return to the parent directory. If at a root node, restore
680 * the initial working directory. If we came through a symlink,
681 * go back through the file descriptor. Otherwise, move up
682 * one level, via "..".
684 if (p->fts_level == FTS_ROOTLEVEL) {
685 if (RESTORE_INITIAL_CWD(sp)) {
686 p->fts_errno = errno;
689 } else if (p->fts_flags & FTS_SYMFOLLOW) {
690 if (FCHDIR(sp, p->fts_symfd)) {
691 int saved_errno = errno;
692 (void)close(p->fts_symfd);
693 __set_errno (saved_errno);
694 p->fts_errno = errno;
697 (void)close(p->fts_symfd);
698 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
699 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
700 p->fts_errno = errno;
703 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
704 if (p->fts_errno == 0)
705 LEAVE_DIR (sp, p, "3");
707 return ISSET(FTS_STOP) ? NULL : p;
711 * Fts_set takes the stream as an argument although it's not used in this
712 * implementation; it would be necessary if anyone wanted to add global
713 * semantics to fts using fts_set. An error return is allowed for similar
718 fts_set(FTS *sp ATTRIBUTE_UNUSED, FTSENT *p, int instr)
720 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
721 instr != FTS_NOINSTR && instr != FTS_SKIP) {
722 __set_errno (EINVAL);
725 p->fts_instr = instr;
730 fts_children (register FTS *sp, int instr)
735 if (instr != 0 && instr != FTS_NAMEONLY) {
736 __set_errno (EINVAL);
740 /* Set current node pointer. */
744 * Errno set to 0 so user can distinguish empty directory from
749 /* Fatal errors stop here. */
753 /* Return logical hierarchy of user's arguments. */
754 if (p->fts_info == FTS_INIT)
755 return (p->fts_link);
758 * If not a directory being visited in pre-order, stop here. Could
759 * allow FTS_DNR, assuming the user has fixed the problem, but the
760 * same effect is available with FTS_AGAIN.
762 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
765 /* Free up any previous child list. */
766 if (sp->fts_child != NULL)
767 fts_lfree(sp->fts_child);
769 if (instr == FTS_NAMEONLY) {
776 * If using chdir on a relative file name and called BEFORE fts_read
777 * does its chdir to the root of a traversal, we can lose -- we need to
778 * chdir into the subdirectory, and we don't know where the current
779 * directory is, so we can't get back so that the upcoming chdir by
780 * fts_read will work.
782 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
784 return (sp->fts_child = fts_build(sp, instr));
786 if ((fd = diropen (sp, ".")) < 0)
787 return (sp->fts_child = NULL);
788 sp->fts_child = fts_build(sp, instr);
789 if (ISSET(FTS_CWDFD))
791 cwd_advance_fd (sp, fd);
797 int saved_errno = errno;
799 __set_errno (saved_errno);
804 return (sp->fts_child);
808 * This is the tricky part -- do not casually change *anything* in here. The
809 * idea is to build the linked list of entries that are used by fts_children
810 * and fts_read. There are lots of special cases.
812 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
813 * set and it's a physical walk (so that symbolic links can't be directories),
814 * we can do things quickly. First, if it's a 4.4BSD file system, the type
815 * of the file is in the directory entry. Otherwise, we assume that the number
816 * of subdirectories in a node is equal to the number of links to the parent.
817 * The former skips all stat calls. The latter skips stat calls in any leaf
818 * directories and for any files after the subdirectories in the directory have
819 * been found, cutting the stat calls by about 2/3.
823 fts_build (register FTS *sp, int type)
825 register struct dirent *dp;
826 register FTSENT *p, *head;
827 register size_t nitems;
837 size_t len, maxlen, new_len;
840 /* Set current node pointer. */
844 * Open the directory for reading. If this fails, we're done.
845 * If being called from fts_read, set the fts_info field.
847 #if defined FTS_WHITEOUT && 0
848 if (ISSET(FTS_WHITEOUT))
849 oflag = DTF_NODUP|DTF_REWIND;
851 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
853 # define __opendir2(file, flag) \
854 ( ! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
855 ? opendirat(sp->fts_cwd_fd, file) \
858 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
860 cur->fts_info = FTS_DNR;
861 cur->fts_errno = errno;
867 * Nlinks is the number of possible entries of type directory in the
868 * directory if we're cheating on stat calls, 0 if we're not doing
869 * any stat calls at all, (nlink_t) -1 if we're statting everything.
871 if (type == BNAMES) {
873 /* Be quiet about nostat, GCC. */
875 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
876 nlinks = (cur->fts_statp->st_nlink
877 - (ISSET(FTS_SEEDOT) ? 0 : 2));
885 * If we're going to need to stat anything or we want to descend
886 * and stay in the directory, chdir. If this fails we keep going,
887 * but set a flag so we don't chdir after the post-order visit.
888 * We won't be able to stat anything, but we can still return the
889 * names themselves. Note, that since fts_read won't be able to
890 * chdir into the directory, it will have to return different file
891 * names than before, i.e. "a/b" instead of "b". Since the node
892 * has already been visited in pre-order, have to wait until the
893 * post-order visit to return the error. There is a special case
894 * here, if there was nothing to stat then it's not an error to
895 * not be able to stat. This is all fairly nasty. If a program
896 * needed sorted entries or stat information, they had better be
897 * checking FTS_NS on the returned nodes.
899 if (nlinks || type == BREAD) {
900 int dir_fd = dirfd(dirp);
901 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
902 dir_fd = dup (dir_fd);
903 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
904 if (nlinks && type == BREAD)
905 cur->fts_errno = errno;
906 cur->fts_flags |= FTS_DONTCHDIR;
909 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
918 * Figure out the max file name length that can be stored in the
919 * current buffer -- the inner loop allocates more space as necessary.
920 * We really wouldn't have to do the maxlen calculations here, we
921 * could do them in fts_read before returning the name, but it's a
922 * lot easier here since the length is part of the dirent structure.
924 * If not changing directories set a pointer so that can just append
925 * each new component into the file name.
928 if (ISSET(FTS_NOCHDIR)) {
929 cp = sp->fts_path + len;
932 /* GCC, you're too verbose. */
936 maxlen = sp->fts_pathlen - len;
938 level = cur->fts_level + 1;
940 /* Read the directory, attaching each entry to the `link' pointer. */
942 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {
943 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
946 if ((p = fts_alloc (sp, dp->d_name,
947 _D_EXACT_NAMLEN (dp))) == NULL)
949 if (_D_EXACT_NAMLEN (dp) >= maxlen) {
950 /* include space for NUL */
951 oldaddr = sp->fts_path;
952 if (! fts_palloc(sp, _D_EXACT_NAMLEN (dp) + len + 1)) {
954 * No more memory. Save
955 * errno, free up the current structure and the
956 * structures already allocated.
958 mem1: saved_errno = errno;
962 cur->fts_info = FTS_ERR;
964 __set_errno (saved_errno);
967 /* Did realloc() change the pointer? */
968 if (oldaddr != sp->fts_path) {
970 if (ISSET(FTS_NOCHDIR))
971 cp = sp->fts_path + len;
973 maxlen = sp->fts_pathlen - len;
976 new_len = len + _D_EXACT_NAMLEN (dp);
979 * In the unlikely even that we would end up
980 * with a file name longer than SIZE_MAX, free up
981 * the current structure and the structures already
982 * allocated, then error out with ENAMETOOLONG.
987 cur->fts_info = FTS_ERR;
989 __set_errno (ENAMETOOLONG);
992 p->fts_level = level;
993 p->fts_parent = sp->fts_cur;
994 p->fts_pathlen = new_len;
996 #if defined FTS_WHITEOUT && 0
997 if (dp->d_type == DT_WHT)
998 p->fts_flags |= FTS_ISW;
1001 /* Build a file name for fts_stat to stat. */
1002 if (ISSET(FTS_NOCHDIR)) {
1003 p->fts_accpath = p->fts_path;
1004 memmove(cp, p->fts_name, p->fts_namelen + 1);
1006 p->fts_accpath = p->fts_name;
1008 p->fts_info = fts_stat(sp, p, false);
1010 /* Decrement link count if applicable. */
1011 if (nlinks > 0 && (p->fts_info == FTS_D ||
1012 p->fts_info == FTS_DC || p->fts_info == FTS_DOT))
1015 /* We walk in directory order so "ls -f" doesn't get upset. */
1029 * If realloc() changed the address of the file name, adjust the
1030 * addresses for the rest of the tree and the dir list.
1033 fts_padjust(sp, head);
1036 * If not changing directories, reset the file name back to original
1039 if (ISSET(FTS_NOCHDIR)) {
1040 if (len == sp->fts_pathlen || nitems == 0)
1046 * If descended after called from fts_children or after called from
1047 * fts_read and nothing found, get back. At the root level we use
1048 * the saved fd; if one of fts_open()'s arguments is a relative name
1049 * to an empty directory, we wind up here with no other way back. If
1050 * can't get back, we're done.
1052 if (descend && (type == BCHILD || !nitems) &&
1053 (cur->fts_level == FTS_ROOTLEVEL
1054 ? RESTORE_INITIAL_CWD(sp)
1055 : fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
1056 cur->fts_info = FTS_ERR;
1062 /* If didn't find anything, return NULL. */
1065 cur->fts_info = FTS_DP;
1070 /* Sort the entries. */
1071 if (sp->fts_compar && nitems > 1)
1072 head = fts_sort(sp, head, nitems);
1078 /* Walk ->fts_parent links starting at E_CURR, until the root of the
1079 current hierarchy. There should be a directory with dev/inode
1080 matching those of AD. If not, print a lot of diagnostics. */
1082 find_matching_ancestor (FTSENT const *e_curr, struct Active_dir const *ad)
1085 for (ent = e_curr; ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1087 if (ad->ino == ent->fts_statp->st_ino
1088 && ad->dev == ent->fts_statp->st_dev)
1091 printf ("ERROR: tree dir, %s, not active\n", ad->fts_ent->fts_accpath);
1092 printf ("active dirs:\n");
1094 ent->fts_level >= FTS_ROOTLEVEL; ent = ent->fts_parent)
1095 printf (" %s(%"PRIuMAX"/%"PRIuMAX") to %s(%"PRIuMAX"/%"PRIuMAX")...\n",
1096 ad->fts_ent->fts_accpath,
1097 (uintmax_t) ad->dev,
1098 (uintmax_t) ad->ino,
1100 (uintmax_t) ent->fts_statp->st_dev,
1101 (uintmax_t) ent->fts_statp->st_ino);
1105 fts_cross_check (FTS const *sp)
1107 FTSENT const *ent = sp->fts_cur;
1109 if ( ! ISSET (FTS_TIGHT_CYCLE_CHECK))
1112 Dprintf (("fts-cross-check cur=%s\n", ent->fts_path));
1113 /* Make sure every parent dir is in the tree. */
1114 for (t = ent->fts_parent; t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1116 struct Active_dir ad;
1117 ad.ino = t->fts_statp->st_ino;
1118 ad.dev = t->fts_statp->st_dev;
1119 if ( ! hash_lookup (sp->fts_cycle.ht, &ad))
1120 printf ("ERROR: active dir, %s, not in tree\n", t->fts_path);
1123 /* Make sure every dir in the tree is an active dir.
1124 But ENT is not necessarily a directory. If so, just skip this part. */
1125 if (ent->fts_parent->fts_level >= FTS_ROOTLEVEL
1126 && (ent->fts_info == FTS_DP
1127 || ent->fts_info == FTS_D))
1129 struct Active_dir *ad;
1130 for (ad = hash_get_first (sp->fts_cycle.ht); ad != NULL;
1131 ad = hash_get_next (sp->fts_cycle.ht, ad))
1133 find_matching_ancestor (ent, ad);
1139 static unsigned short int
1141 fts_stat(FTS *sp, register FTSENT *p, bool follow)
1143 struct stat *sbp = p->fts_statp;
1146 #if defined FTS_WHITEOUT && 0
1147 /* check for whiteout */
1148 if (p->fts_flags & FTS_ISW) {
1149 memset(sbp, '\0', sizeof (*sbp));
1150 sbp->st_mode = S_IFWHT;
1156 * If doing a logical walk, or application requested FTS_FOLLOW, do
1157 * a stat(2). If that fails, check for a non-existent symlink. If
1158 * fail, set the errno from the stat call.
1160 if (ISSET(FTS_LOGICAL) || follow) {
1161 if (stat(p->fts_accpath, sbp)) {
1162 saved_errno = errno;
1164 && lstat(p->fts_accpath, sbp) == 0) {
1166 return (FTS_SLNONE);
1168 p->fts_errno = saved_errno;
1171 } else if (fstatat(sp->fts_cwd_fd, p->fts_accpath, sbp,
1172 AT_SYMLINK_NOFOLLOW)) {
1173 p->fts_errno = errno;
1174 err: memset(sbp, 0, sizeof(struct stat));
1178 if (S_ISDIR(sbp->st_mode)) {
1179 if (ISDOT(p->fts_name))
1185 * Cycle detection is done by brute force when the directory
1186 * is first encountered. If the tree gets deep enough or the
1187 * number of symbolic links to directories is high enough,
1188 * something faster might be worthwhile.
1192 for (t = p->fts_parent;
1193 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1194 if (sbp->st_ino == t->fts_statp->st_ino
1195 && sbp->st_dev == t->fts_statp->st_dev)
1205 if (S_ISLNK(sbp->st_mode))
1207 if (S_ISREG(sbp->st_mode))
1209 return (FTS_DEFAULT);
1213 fts_compar (void const *a, void const *b)
1215 /* Convert A and B to the correct types, to pacify the compiler, and
1216 for portability to bizarre hosts where "void const *" and "FTSENT
1217 const **" differ in runtime representation. The comparison
1218 function cannot modify *a and *b, but there is no compile-time
1220 FTSENT const **pa = (FTSENT const **) a;
1221 FTSENT const **pb = (FTSENT const **) b;
1222 return pa[0]->fts_fts->fts_compar (pa, pb);
1227 fts_sort (FTS *sp, FTSENT *head, register size_t nitems)
1229 register FTSENT **ap, *p;
1231 /* On most modern hosts, void * and FTSENT ** have the same
1232 run-time representation, and one can convert sp->fts_compar to
1233 the type qsort expects without problem. Use the heuristic that
1234 this is OK if the two pointer types are the same size, and if
1235 converting FTSENT ** to long int is the same as converting
1236 FTSENT ** to void * and then to long int. This heuristic isn't
1237 valid in general but we don't know of any counterexamples. */
1239 int (*compare) (void const *, void const *) =
1240 ((sizeof &dummy == sizeof (void *)
1241 && (long int) &dummy == (long int) (void *) &dummy)
1242 ? (int (*) (void const *, void const *)) sp->fts_compar
1246 * Construct an array of pointers to the structures and call qsort(3).
1247 * Reassemble the array in the order returned by qsort. If unable to
1248 * sort for memory reasons, return the directory entries in their
1249 * current order. Allocate enough space for the current needs plus
1250 * 40 so don't realloc one entry at a time.
1252 if (nitems > sp->fts_nitems) {
1255 sp->fts_nitems = nitems + 40;
1256 if (SIZE_MAX / sizeof *a < sp->fts_nitems
1257 || ! (a = realloc (sp->fts_array,
1258 sp->fts_nitems * sizeof *a))) {
1259 free(sp->fts_array);
1260 sp->fts_array = NULL;
1266 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1268 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), compare);
1269 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1270 ap[0]->fts_link = ap[1];
1271 ap[0]->fts_link = NULL;
1277 fts_alloc (FTS *sp, const char *name, register size_t namelen)
1283 * The file name is a variable length array. Allocate the FTSENT
1284 * structure and the file name in one chunk.
1286 len = sizeof(FTSENT) + namelen;
1287 if ((p = malloc(len)) == NULL)
1290 /* Copy the name and guarantee NUL termination. */
1291 memmove(p->fts_name, name, namelen);
1292 p->fts_name[namelen] = '\0';
1294 p->fts_namelen = namelen;
1296 p->fts_path = sp->fts_path;
1299 p->fts_instr = FTS_NOINSTR;
1301 p->fts_pointer = NULL;
1307 fts_lfree (register FTSENT *head)
1311 /* Free a linked list of structures. */
1312 while ((p = head)) {
1313 head = head->fts_link;
1319 * Allow essentially unlimited file name lengths; find, rm, ls should
1320 * all work on any tree. Most systems will allow creation of file
1321 * names much longer than MAXPATHLEN, even though the kernel won't
1322 * resolve them. Add the size (not just what's needed) plus 256 bytes
1323 * so don't realloc the file name 2 bytes at a time.
1327 fts_palloc (FTS *sp, size_t more)
1330 size_t new_len = sp->fts_pathlen + more + 256;
1333 * See if fts_pathlen would overflow.
1335 if (new_len < sp->fts_pathlen) {
1337 sp->fts_path = NULL;
1338 __set_errno (ENAMETOOLONG);
1341 sp->fts_pathlen = new_len;
1342 p = realloc(sp->fts_path, sp->fts_pathlen);
1345 sp->fts_path = NULL;
1353 * When the file name is realloc'd, have to fix all of the pointers in
1354 * structures already returned.
1358 fts_padjust (FTS *sp, FTSENT *head)
1361 char *addr = sp->fts_path;
1363 #define ADJUST(p) do { \
1364 if ((p)->fts_accpath != (p)->fts_name) { \
1365 (p)->fts_accpath = \
1366 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \
1368 (p)->fts_path = addr; \
1370 /* Adjust the current set of children. */
1371 for (p = sp->fts_child; p; p = p->fts_link)
1374 /* Adjust the rest of the tree, including the current level. */
1375 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1377 p = p->fts_link ? p->fts_link : p->fts_parent;
1383 fts_maxarglen (char * const *argv)
1387 for (max = 0; *argv; ++argv)
1388 if ((len = strlen(*argv)) > max)
1394 * Change to dir specified by fd or file name without getting
1395 * tricked by someone changing the world out from underneath us.
1396 * Assumes p->fts_statp->st_dev and p->fts_statp->st_ino are filled in.
1397 * If FD is non-negative, expect it to be used after this function returns,
1398 * and to be closed eventually. So don't pass e.g., `dirfd(dirp)' and then
1399 * do closedir(dirp), because that would invalidate the saved FD.
1400 * Upon failure, close FD immediately and return nonzero.
1404 fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
1409 if (ISSET(FTS_NOCHDIR)) {
1410 if (ISSET(FTS_CWDFD) && 0 <= fd)
1414 if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
1417 /* The following dev/inode check is necessary if we're doing
1418 a `logical' traversal (through symlinks, a la chown -L),
1419 if the system lacks O_NOFOLLOW support, or if we're changing
1420 to "..". In the latter case, O_NOFOLLOW can't help. In
1421 general (when the target is not ".."), diropen's use of
1422 O_NOFOLLOW ensures we don't mistakenly follow a symlink,
1423 so we can avoid the expense of this fstat. */
1424 if (ISSET(FTS_LOGICAL) || ! HAVE_WORKING_O_NOFOLLOW
1425 || (dir && STREQ (dir, "..")))
1428 if (fstat(newfd, &sb))
1433 if (p->fts_statp->st_dev != sb.st_dev
1434 || p->fts_statp->st_ino != sb.st_ino)
1436 __set_errno (ENOENT); /* disinformation */
1442 if (ISSET(FTS_CWDFD))
1444 cwd_advance_fd (sp, newfd);
1448 ret = fchdir(newfd);
1454 __set_errno (oerrno);