1 /* $NetBSD: fts.c,v 1.44 2012/03/14 00:25:19 christos Exp $ */
2
3 /*-
4 * Copyright (c) 1990, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #if 0
33 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
34 #else
35 /* __RCSID("$NetBSD: fts.c,v 1.44 2012/03/14 00:25:19 christos Exp $"); */
36 #endif
37
38 #ifdef HAVE_CONFIG_H
39 #include <config.h>
40 #endif
41
42 #define _BSD_SOURCE
43
44 #include <limits.h>
45 /* #include "namespace.h" */
46 #ifdef HAVE_SYS_PARAM_H
47 #include <sys/param.h>
48 #else
49 #include <stdio.h>
50 #endif
51 #include <sys/stat.h>
52
53 #include <assert.h>
54 #include <dirent.h>
55 #include <errno.h>
56 #include <fcntl.h>
57 #include "gawkfts.h"
58 #include <stdlib.h>
59 #include <string.h>
60 #include <unistd.h>
61
62 #include "gawkdirfd.h"
63
64 #if ! defined(S_ISREG) && defined(S_IFREG)
65 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
66 #endif
67
68 /*
69 #if ! HAVE_NBTOOL_CONFIG_H
70 #define HAVE_STRUCT_DIRENT_D_NAMLEN
71 #endif
72 */
73
74 #ifndef MAX
75 static int MAX(int x, int y)
76 {
77 if (x > y)
78 return x;
79
80 return y;
81 }
82 #endif
83
84
85 static FTSENT *fts_alloc(FTS *, const char *, size_t);
86 static FTSENT *fts_build(FTS *, int);
87 static void fts_free(FTSENT *);
88 static void fts_lfree(FTSENT *);
89 static void fts_load(FTS *, FTSENT *);
90 static size_t fts_maxarglen(char * const *);
91 static size_t fts_pow2(size_t);
92 static int fts_palloc(FTS *, size_t);
93 static void fts_padjust(FTS *, FTSENT *);
94 static FTSENT *fts_sort(FTS *, FTSENT *, size_t);
95 static unsigned short fts_stat(FTS *, FTSENT *, int);
96 static int fts_safe_changedir(const FTS *, const FTSENT *, int,
97 const char *);
98
99 #if defined(ALIGNBYTES) && defined(ALIGN)
100 #define FTS_ALLOC_ALIGNED 1
101 #else
102 #undef FTS_ALLOC_ALIGNED
103 #endif
104
105 #ifndef ftsent_namelen_truncate
106 #define ftsent_namelen_truncate(a) \
107 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a))
108 #endif
109 #ifndef ftsent_pathlen_truncate
110 #define ftsent_pathlen_truncate(a) \
111 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a))
112 #endif
113 #ifndef fts_pathlen_truncate
114 #define fts_pathlen_truncate(a) \
115 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a))
116 #endif
117 #ifndef fts_nitems_truncate
118 #define fts_nitems_truncate(a) \
119 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a))
120 #endif
121
122 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
123
124 #define CLR(opt) (sp->fts_options &= ~(opt))
125 #define ISSET(opt) (sp->fts_options & (opt))
126 #define SET(opt) (sp->fts_options |= (opt))
127
128 #define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path))
129 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd))
130
131 /* fts_build flags */
132 #define BCHILD 1 /* fts_children */
133 #define BNAMES 2 /* fts_children, names only */
134 #define BREAD 3 /* fts_read */
135
136 #ifndef DTF_HIDEW
137 #undef FTS_WHITEOUT
138 #endif
139
140 #define _DIAGASSERT(expression)
141
142 #ifndef MAXPATHLEN
143 #define MAXPATHLEN 1024 /* a guess */
144 #endif
145
146 FTS *
147 fts_open(char * const *argv, int options,
148 int (*compar)(const FTSENT **, const FTSENT **))
149 {
150 FTS *sp;
151 FTSENT *p, *root;
152 size_t nitems;
153 FTSENT *parent, *tmp = NULL; /* pacify gcc */
154 size_t len;
155
156 _DIAGASSERT(argv != NULL);
157
158 /* Options check. */
159 if (options & ~FTS_OPTIONMASK) {
160 errno = EINVAL;
161 return (NULL);
162 }
163
164 /* Allocate/initialize the stream */
165 if ((sp = calloc(1, (unsigned int)sizeof(FTS))) == NULL)
166 return (NULL);
167 sp->fts_compar = compar;
168 sp->fts_options = options;
169
170 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */
171 if (ISSET(FTS_LOGICAL))
172 SET(FTS_NOCHDIR);
173
174 /*
175 * Start out with 1K of path space, and enough, in any case,
176 * to hold the user's paths.
177 */
178 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN)))
179 goto mem1;
180
181 /* Allocate/initialize root's parent. */
182 if ((parent = fts_alloc(sp, "", 0)) == NULL)
183 goto mem2;
184 parent->fts_level = FTS_ROOTPARENTLEVEL;
185
186 /* Allocate/initialize root(s). */
187 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) {
188 /* Don't allow zero-length paths. */
189 if ((len = strlen(*argv)) == 0) {
190 errno = ENOENT;
191 goto mem3;
192 }
193
194 if ((p = fts_alloc(sp, *argv, len)) == NULL)
195 goto mem3;
196 p->fts_level = FTS_ROOTLEVEL;
197 p->fts_parent = parent;
198 p->fts_accpath = p->fts_name;
199 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW));
200
201 /* Command-line "." and ".." are real directories. */
202 if (p->fts_info == FTS_DOT)
203 p->fts_info = FTS_D;
204
205 /*
206 * If comparison routine supplied, traverse in sorted
207 * order; otherwise traverse in the order specified.
208 */
209 if (compar) {
210 p->fts_link = root;
211 root = p;
212 } else {
213 p->fts_link = NULL;
214 if (root == NULL)
215 tmp = root = p;
216 else {
217 tmp->fts_link = p;
218 tmp = p;
219 }
220 }
221 }
222 if (compar && nitems > 1)
223 root = fts_sort(sp, root, nitems);
224
225 /*
226 * Allocate a dummy pointer and make fts_read think that we've just
227 * finished the node before the root(s); set p->fts_info to FTS_INIT
228 * so that everything about the "current" node is ignored.
229 */
230 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)
231 goto mem4;
232 sp->fts_cur->fts_link = root;
233 sp->fts_cur->fts_info = FTS_INIT;
234
235 /*
236 * If using chdir(2), grab a file descriptor pointing to dot to insure
237 * that we can get back here; this could be avoided for some paths,
238 * but almost certainly not worth the effort. Slashes, symbolic links,
239 * and ".." are all fairly nasty problems. Note, if we can't get the
240 * descriptor we run anyway, just more slowly.
241 */
242 #ifndef O_CLOEXEC
243 #define O_CLOEXEC 0
244 #endif
245 if (!ISSET(FTS_NOCHDIR)) {
246 if ((sp->fts_rfd = open(".", O_RDONLY | O_CLOEXEC, 0)) == -1)
247 SET(FTS_NOCHDIR);
248 }
249
250 if (nitems == 0)
251 fts_free(parent);
252
253 return (sp);
254
255 mem4: if (sp->fts_array != NULL)
256 free(sp->fts_array);
257 mem3: fts_lfree(root);
258 fts_free(parent);
259 mem2: free(sp->fts_path);
260 mem1: free(sp);
261 return (NULL);
262 }
263
264 static void
265 fts_load(FTS *sp, FTSENT *p)
266 {
267 size_t len;
268 char *cp;
269
270 _DIAGASSERT(sp != NULL);
271 _DIAGASSERT(p != NULL);
272
273 /*
274 * Load the stream structure for the next traversal. Since we don't
275 * actually enter the directory until after the preorder visit, set
276 * the fts_accpath field specially so the chdir gets done to the right
277 * place and the user can access the first node. From fts_open it's
278 * known that the path will fit.
279 */
280 len = p->fts_pathlen = p->fts_namelen;
281 memmove(sp->fts_path, p->fts_name, len + 1);
282 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) {
283 len = strlen(++cp);
284 memmove(p->fts_name, cp, len + 1);
285 p->fts_namelen = ftsent_namelen_truncate(len);
286 }
287 p->fts_accpath = p->fts_path = sp->fts_path;
288 sp->fts_dev = p->fts_dev;
289 }
290
291 int
292 fts_close(FTS *sp)
293 {
294 FTSENT *freep, *p;
295 int saved_errno = 0;
296
297 _DIAGASSERT(sp != NULL);
298
299 /*
300 * This still works if we haven't read anything -- the dummy structure
301 * points to the root list, so we step through to the end of the root
302 * list which has a valid parent pointer.
303 */
304 if (sp->fts_cur) {
305 if (sp->fts_cur->fts_flags & FTS_SYMFOLLOW)
306 (void)close(sp->fts_cur->fts_symfd);
307 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {
308 freep = p;
309 p = p->fts_link ? p->fts_link : p->fts_parent;
310 fts_free(freep);
311 }
312 fts_free(p);
313 }
314
315 /* Free up child linked list, sort array, path buffer. */
316 if (sp->fts_child)
317 fts_lfree(sp->fts_child);
318 if (sp->fts_array)
319 free(sp->fts_array);
320 free(sp->fts_path);
321
322 /* Return to original directory, save errno if necessary. */
323 if (!ISSET(FTS_NOCHDIR)) {
324 if (fchdir(sp->fts_rfd) == -1)
325 saved_errno = errno;
326 (void)close(sp->fts_rfd);
327 }
328
329 /* Free up the stream pointer. */
330 free(sp);
331 if (saved_errno) {
332 errno = saved_errno;
333 return -1;
334 }
335
336 return 0;
337 }
338
339 #if !defined(__FTS_COMPAT_TAILINGSLASH)
340
341 /*
342 * Special case of "/" at the end of the path so that slashes aren't
343 * appended which would cause paths to be written as "....//foo".
344 */
345 #define NAPPEND(p) \
346 (p->fts_path[p->fts_pathlen - 1] == '/' \
347 ? p->fts_pathlen - 1 : p->fts_pathlen)
348
349 #else /* !defined(__FTS_COMPAT_TAILINGSLASH) */
350
351 /*
352 * compatibility with the old behaviour.
353 *
354 * Special case a root of "/" so that slashes aren't appended which would
355 * cause paths to be written as "//foo".
356 */
357
358 #define NAPPEND(p) \
359 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \
360 p->fts_path[0] == '/' ? 0 : p->fts_pathlen)
361
362 #endif /* !defined(__FTS_COMPAT_TAILINGSLASH) */
363
364 FTSENT *
365 fts_read(FTS *sp)
366 {
367 FTSENT *p, *tmp;
368 int instr;
369 char *t;
370 int saved_errno;
371
372 _DIAGASSERT(sp != NULL);
373
374 /* If finished or unrecoverable error, return NULL. */
375 if (sp->fts_cur == NULL || ISSET(FTS_STOP))
376 return (NULL);
377
378 /* Set current node pointer. */
379 p = sp->fts_cur;
380
381 /* Save and zero out user instructions. */
382 instr = p->fts_instr;
383 p->fts_instr = FTS_NOINSTR;
384
385 /* Any type of file may be re-visited; re-stat and re-turn. */
386 if (instr == FTS_AGAIN) {
387 p->fts_info = fts_stat(sp, p, 0);
388 return (p);
389 }
390
391 /*
392 * Following a symlink -- SLNONE test allows application to see
393 * SLNONE and recover. If indirecting through a symlink, have
394 * keep a pointer to current location. If unable to get that
395 * pointer, follow fails.
396 */
397 if (instr == FTS_FOLLOW &&
398 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
399 p->fts_info = fts_stat(sp, p, 1);
400 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
401 if ((p->fts_symfd = open(".", O_RDONLY | O_CLOEXEC, 0))
402 == -1) {
403 p->fts_errno = errno;
404 p->fts_info = FTS_ERR;
405 } else
406 p->fts_flags |= FTS_SYMFOLLOW;
407 }
408 return (p);
409 }
410
411 /* Directory in pre-order. */
412 if (p->fts_info == FTS_D) {
413 /* If skipped or crossed mount point, do post-order visit. */
414 if (instr == FTS_SKIP ||
415 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) {
416 if (p->fts_flags & FTS_SYMFOLLOW)
417 (void)close(p->fts_symfd);
418 if (sp->fts_child) {
419 fts_lfree(sp->fts_child);
420 sp->fts_child = NULL;
421 }
422 p->fts_info = FTS_DP;
423 return (p);
424 }
425
426 /* Rebuild if only read the names and now traversing. */
427 if (sp->fts_child && ISSET(FTS_NAMEONLY)) {
428 CLR(FTS_NAMEONLY);
429 fts_lfree(sp->fts_child);
430 sp->fts_child = NULL;
431 }
432
433 /*
434 * Cd to the subdirectory.
435 *
436 * If have already read and now fail to chdir, whack the list
437 * to make the names come out right, and set the parent errno
438 * so the application will eventually get an error condition.
439 * Set the FTS_DONTCHDIR flag so that when we logically change
440 * directories back to the parent we don't do a chdir.
441 *
442 * If haven't read do so. If the read fails, fts_build sets
443 * FTS_STOP or the fts_info field of the node.
444 */
445 if (sp->fts_child) {
446 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) {
447 p->fts_errno = errno;
448 p->fts_flags |= FTS_DONTCHDIR;
449 for (p = sp->fts_child; p; p = p->fts_link)
450 p->fts_accpath =
451 p->fts_parent->fts_accpath;
452 }
453 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {
454 if (ISSET(FTS_STOP))
455 return (NULL);
456 return (p);
457 }
458 p = sp->fts_child;
459 sp->fts_child = NULL;
460 goto name;
461 }
462
463 /* Move to the next node on this level. */
464 next: tmp = p;
465 if ((p = p->fts_link) != NULL) {
466 fts_free(tmp);
467
468 /*
469 * If reached the top, return to the original directory, and
470 * load the paths for the next root.
471 */
472 if (p->fts_level == FTS_ROOTLEVEL) {
473 if (FCHDIR(sp, sp->fts_rfd)) {
474 SET(FTS_STOP);
475 return (NULL);
476 }
477 fts_load(sp, p);
478 return (sp->fts_cur = p);
479 }
480
481 /*
482 * User may have called fts_set on the node. If skipped,
483 * ignore. If followed, get a file descriptor so we can
484 * get back if necessary.
485 */
486 if (p->fts_instr == FTS_SKIP)
487 goto next;
488 if (p->fts_instr == FTS_FOLLOW) {
489 p->fts_info = fts_stat(sp, p, 1);
490 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
491 if ((p->fts_symfd =
492 open(".", O_RDONLY | O_CLOEXEC, 0)) == -1) {
493 p->fts_errno = errno;
494 p->fts_info = FTS_ERR;
495 } else
496 p->fts_flags |= FTS_SYMFOLLOW;
497 }
498 p->fts_instr = FTS_NOINSTR;
499 }
500
501 name: t = sp->fts_path + NAPPEND(p->fts_parent);
502 *t++ = '/';
503 memmove(t, p->fts_name, (size_t)(p->fts_namelen + 1));
504 return (sp->fts_cur = p);
505 }
506
507 /* Move up to the parent node. */
508 p = tmp->fts_parent;
509 fts_free(tmp);
510
511 if (p->fts_level == FTS_ROOTPARENTLEVEL) {
512 /*
513 * Done; free everything up and set errno to 0 so the user
514 * can distinguish between error and EOF.
515 */
516 fts_free(p);
517 errno = 0;
518 return (sp->fts_cur = NULL);
519 }
520
521 /* Nul terminate the pathname. */
522 sp->fts_path[p->fts_pathlen] = '\0';
523
524 /*
525 * Return to the parent directory. If at a root node or came through
526 * a symlink, go back through the file descriptor. Otherwise, cd up
527 * one directory.
528 */
529 if (p->fts_level == FTS_ROOTLEVEL) {
530 if (FCHDIR(sp, sp->fts_rfd)) {
531 SET(FTS_STOP);
532 return (NULL);
533 }
534 } else if (p->fts_flags & FTS_SYMFOLLOW) {
535 if (FCHDIR(sp, p->fts_symfd)) {
536 saved_errno = errno;
537 (void)close(p->fts_symfd);
538 errno = saved_errno;
539 SET(FTS_STOP);
540 return (NULL);
541 }
542 (void)close(p->fts_symfd);
543 } else if (!(p->fts_flags & FTS_DONTCHDIR) &&
544 fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
545 SET(FTS_STOP);
546 return (NULL);
547 }
548 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
549 return (sp->fts_cur = p);
550 }
551
552 /*
553 * Fts_set takes the stream as an argument although it's not used in this
554 * implementation; it would be necessary if anyone wanted to add global
555 * semantics to fts using fts_set. An error return is allowed for similar
556 * reasons.
557 */
558 /* ARGSUSED */
559 int
560 fts_set(FTS *sp, FTSENT *p, int instr)
561 {
562 (void) sp; /* silence warnings */
563 _DIAGASSERT(sp != NULL);
564 _DIAGASSERT(p != NULL);
565
566 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW &&
567 instr != FTS_NOINSTR && instr != FTS_SKIP) {
568 errno = EINVAL;
569 return (1);
570 }
571 p->fts_instr = instr;
572 return (0);
573 }
574
575 FTSENT *
576 fts_children(FTS *sp, int instr)
577 {
578 FTSENT *p;
579 int fd;
580
581 _DIAGASSERT(sp != NULL);
582
583 if (instr && instr != FTS_NAMEONLY) {
584 errno = EINVAL;
585 return (NULL);
586 }
587
588 /* Set current node pointer. */
589 p = sp->fts_cur;
590
591 /*
592 * Errno set to 0 so user can distinguish empty directory from
593 * an error.
594 */
595 errno = 0;
596
597 /* Fatal errors stop here. */
598 if (ISSET(FTS_STOP))
599 return (NULL);
600
601 /* Return logical hierarchy of user's arguments. */
602 if (p->fts_info == FTS_INIT)
603 return (p->fts_link);
604
605 /*
606 * If not a directory being visited in pre-order, stop here. Could
607 * allow FTS_DNR, assuming the user has fixed the problem, but the
608 * same effect is available with FTS_AGAIN.
609 */
610 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)
611 return (NULL);
612
613 /* Free up any previous child list. */
614 if (sp->fts_child)
615 fts_lfree(sp->fts_child);
616
617 if (instr == FTS_NAMEONLY) {
618 SET(FTS_NAMEONLY);
619 instr = BNAMES;
620 } else
621 instr = BCHILD;
622
623 /*
624 * If using chdir on a relative path and called BEFORE fts_read does
625 * its chdir to the root of a traversal, we can lose -- we need to
626 * chdir into the subdirectory, and we don't know where the current
627 * directory is, so we can't get back so that the upcoming chdir by
628 * fts_read will work.
629 */
630 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' ||
631 ISSET(FTS_NOCHDIR))
632 return (sp->fts_child = fts_build(sp, instr));
633
634 if ((fd = open(".", O_RDONLY, 0)) == -1)
635 return (sp->fts_child = NULL);
636 sp->fts_child = fts_build(sp, instr);
637 if (fchdir(fd)) {
638 (void)close(fd);
639 return (NULL);
640 }
641 (void)close(fd);
642 return (sp->fts_child);
643 }
644
645 /*
646 * This is the tricky part -- do not casually change *anything* in here. The
647 * idea is to build the linked list of entries that are used by fts_children
648 * and fts_read. There are lots of special cases.
649 *
650 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is
651 * set and it's a physical walk (so that symbolic links can't be directories),
652 * we can do things quickly. First, if it's a 4.4BSD file system, the type
653 * of the file is in the directory entry. Otherwise, we assume that the number
654 * of subdirectories in a node is equal to the number of links to the parent.
655 * The former skips all stat calls. The latter skips stat calls in any leaf
656 * directories and for any files after the subdirectories in the directory have
657 * been found, cutting the stat calls by about 2/3.
658 */
659 static FTSENT *
660 fts_build(FTS *sp, int type)
661 {
662 struct dirent *dp;
663 FTSENT *p, *head;
664 size_t nitems;
665 FTSENT *cur, *tail;
666 DIR *dirp;
667 void *oldaddr;
668 size_t dnamlen;
669 int cderrno, descend, level, nlinks, saved_errno, nostat, doadjust;
670 size_t len, maxlen;
671 #ifdef FTS_WHITEOUT
672 int oflag;
673 #endif
674 char *cp = NULL; /* pacify gcc */
675
676 _DIAGASSERT(sp != NULL);
677
678 /* Set current node pointer. */
679 cur = sp->fts_cur;
680
681 /*
682 * Open the directory for reading. If this fails, we're done.
683 * If being called from fts_read, set the fts_info field.
684 */
685 #if 0 /* def FTS_WHITEOUT */
686 if (ISSET(FTS_WHITEOUT))
687 oflag = DTF_NODUP|DTF_REWIND;
688 else
689 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
690 #else
691 #define __opendir2(path, flag) opendir(path)
692 #endif
693 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
694 if (type == BREAD) {
695 cur->fts_info = FTS_DNR;
696 cur->fts_errno = errno;
697 }
698 return (NULL);
699 }
700
701 /*
702 * Nlinks is the number of possible entries of type directory in the
703 * directory if we're cheating on stat calls, 0 if we're not doing
704 * any stat calls at all, -1 if we're doing stats on everything.
705 */
706 if (type == BNAMES) {
707 nlinks = 0;
708 nostat = 1;
709 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {
710 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2);
711 nostat = 1;
712 } else {
713 nlinks = -1;
714 nostat = 0;
715 }
716
717 #ifdef notdef
718 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink);
719 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n",
720 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT));
721 #endif
722 /*
723 * If we're going to need to stat anything or we want to descend
724 * and stay in the directory, chdir. If this fails we keep going,
725 * but set a flag so we don't chdir after the post-order visit.
726 * We won't be able to stat anything, but we can still return the
727 * names themselves. Note, that since fts_read won't be able to
728 * chdir into the directory, it will have to return different path
729 * names than before, i.e. "a/b" instead of "b". Since the node
730 * has already been visited in pre-order, have to wait until the
731 * post-order visit to return the error. There is a special case
732 * here, if there was nothing to stat then it's not an error to
733 * not be able to stat. This is all fairly nasty. If a program
734 * needed sorted entries or stat information, they had better be
735 * checking FTS_NS on the returned nodes.
736 */
737 cderrno = 0;
738 if (nlinks || type == BREAD) {
739 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) {
740 if (nlinks && type == BREAD)
741 cur->fts_errno = errno;
742 cur->fts_flags |= FTS_DONTCHDIR;
743 descend = 0;
744 cderrno = errno;
745 } else
746 descend = 1;
747 } else
748 descend = 0;
749
750 /*
751 * Figure out the max file name length that can be stored in the
752 * current path -- the inner loop allocates more path as necessary.
753 * We really wouldn't have to do the maxlen calculations here, we
754 * could do them in fts_read before returning the path, but it's a
755 * lot easier here since the length is part of the dirent structure.
756 *
757 * If not changing directories set a pointer so that can just append
758 * each new name into the path.
759 */
760 len = NAPPEND(cur);
761 if (ISSET(FTS_NOCHDIR)) {
762 cp = sp->fts_path + len;
763 *cp++ = '/';
764 }
765 len++;
766 maxlen = sp->fts_pathlen - len;
767
768 #if defined(__FTS_COMPAT_LEVEL)
769 if (cur->fts_level == SHRT_MAX) {
770 (void)closedir(dirp);
771 cur->fts_info = FTS_ERR;
772 SET(FTS_STOP);
773 errno = ENAMETOOLONG;
774 return (NULL);
775 }
776 #endif
777
778 level = cur->fts_level + 1;
779
780 /* Read the directory, attaching each entry to the `link' pointer. */
781 doadjust = 0;
782 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) {
783
784 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))
785 continue;
786
787 #if defined(HAVE_STRUCT_DIRENT_D_NAMLEN)
788 dnamlen = dp->d_namlen;
789 #else
790 dnamlen = strlen(dp->d_name);
791 #endif
792 if ((p = fts_alloc(sp, dp->d_name, dnamlen)) == NULL)
793 goto mem1;
794 if (dnamlen >= maxlen) { /* include space for NUL */
795 oldaddr = sp->fts_path;
796 if (fts_palloc(sp, dnamlen + len + 1)) {
797 /*
798 * No more memory for path or structures. Save
799 * errno, free up the current structure and the
800 * structures already allocated.
801 */
802 mem1: saved_errno = errno;
803 if (p)
804 fts_free(p);
805 fts_lfree(head);
806 (void)closedir(dirp);
807 errno = saved_errno;
808 cur->fts_info = FTS_ERR;
809 SET(FTS_STOP);
810 return (NULL);
811 }
812 /* Did realloc() change the pointer? */
813 if (oldaddr != sp->fts_path) {
814 doadjust = 1;
815 if (ISSET(FTS_NOCHDIR))
816 cp = sp->fts_path + len;
817 }
818 maxlen = sp->fts_pathlen - len;
819 }
820
821 #if defined(__FTS_COMPAT_LENGTH)
822 if (len + dnamlen >= USHRT_MAX) {
823 /*
824 * In an FTSENT, fts_pathlen is an unsigned short
825 * so it is possible to wraparound here.
826 * If we do, free up the current structure and the
827 * structures already allocated, then error out
828 * with ENAMETOOLONG.
829 */
830 fts_free(p);
831 fts_lfree(head);
832 (void)closedir(dirp);
833 cur->fts_info = FTS_ERR;
834 SET(FTS_STOP);
835 errno = ENAMETOOLONG;
836 return (NULL);
837 }
838 #endif
839 p->fts_level = level;
840 p->fts_pathlen = ftsent_pathlen_truncate(len + dnamlen);
841 p->fts_parent = sp->fts_cur;
842
843 #ifdef FTS_WHITEOUT
844 if (dp->d_type == DT_WHT)
845 p->fts_flags |= FTS_ISW;
846 #endif
847
848 if (cderrno) {
849 if (nlinks) {
850 p->fts_info = FTS_NS;
851 p->fts_errno = cderrno;
852 } else
853 p->fts_info = FTS_NSOK;
854 p->fts_accpath = cur->fts_accpath;
855 } else if (nlinks == 0
856 #ifdef DT_DIR
857 || (nostat &&
858 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN)
859 #endif
860 ) {
861 p->fts_accpath =
862 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name;
863 p->fts_info = FTS_NSOK;
864 } else {
865 /* Build a file name for fts_stat to stat. */
866 if (ISSET(FTS_NOCHDIR)) {
867 p->fts_accpath = p->fts_path;
868 memmove(cp, p->fts_name,
869 (size_t)(p->fts_namelen + 1));
870 } else
871 p->fts_accpath = p->fts_name;
872 /* Stat it. */
873 p->fts_info = fts_stat(sp, p, 0);
874
875 /* Decrement link count if applicable. */
876 if (nlinks > 0 && (p->fts_info == FTS_D ||
877 p->fts_info == FTS_DC || p->fts_info == FTS_DOT))
878 --nlinks;
879 }
880
881 /* We walk in directory order so "ls -f" doesn't get upset. */
882 p->fts_link = NULL;
883 if (head == NULL)
884 head = tail = p;
885 else {
886 tail->fts_link = p;
887 tail = p;
888 }
889 ++nitems;
890 }
891 (void)closedir(dirp);
892
893 /*
894 * If had to realloc the path, adjust the addresses for the rest
895 * of the tree.
896 */
897 if (doadjust)
898 fts_padjust(sp, head);
899
900 /*
901 * If not changing directories, reset the path back to original
902 * state.
903 */
904 if (ISSET(FTS_NOCHDIR)) {
905 if (len == sp->fts_pathlen || nitems == 0)
906 --cp;
907 *cp = '\0';
908 }
909
910 /*
911 * If descended after called from fts_children or after called from
912 * fts_read and nothing found, get back. At the root level we use
913 * the saved fd; if one of fts_open()'s arguments is a relative path
914 * to an empty directory, we wind up here with no other way back. If
915 * can't get back, we're done.
916 */
917 if (descend && (type == BCHILD || !nitems) &&
918 (cur->fts_level == FTS_ROOTLEVEL ?
919 FCHDIR(sp, sp->fts_rfd) :
920 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
921 fts_lfree(head);
922 cur->fts_info = FTS_ERR;
923 SET(FTS_STOP);
924 return (NULL);
925 }
926
927 /* If didn't find anything, return NULL. */
928 if (!nitems) {
929 if (type == BREAD)
930 cur->fts_info = FTS_DP;
931 return (NULL);
932 }
933
934 /* Sort the entries. */
935 if (sp->fts_compar && nitems > 1)
936 head = fts_sort(sp, head, nitems);
937 return (head);
938 }
939
940 static unsigned short
941 fts_stat(FTS *sp, FTSENT *p, int follow)
942 {
943 FTSENT *t;
944 dev_t dev;
945 ino_t ino;
946 struct stat *sbp, sb;
947 int saved_errno;
948
949 _DIAGASSERT(sp != NULL);
950 _DIAGASSERT(p != NULL);
951
952 /* If user needs stat info, stat buffer already allocated. */
953 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp;
954
955 #ifdef FTS_WHITEOUT
956 /* check for whiteout */
957 if (p->fts_flags & FTS_ISW) {
958 if (sbp != &sb) {
959 memset(sbp, '\0', sizeof (*sbp));
960 sbp->st_mode = S_IFWHT;
961 }
962 return (FTS_W);
963 }
964 #endif
965
966 /*
967 * If doing a logical walk, or application requested FTS_FOLLOW, do
968 * a stat(2). If that fails, check for a non-existent symlink. If
969 * fail, set the errno from the stat call.
970 */
971 if (ISSET(FTS_LOGICAL) || follow) {
972 if (stat(p->fts_accpath, sbp)) {
973 saved_errno = errno;
974 if (!lstat(p->fts_accpath, sbp)) {
975 errno = 0;
976 return (FTS_SLNONE);
977 }
978 p->fts_errno = saved_errno;
979 goto err;
980 }
981 } else if (lstat(p->fts_accpath, sbp)) {
982 p->fts_errno = errno;
983 err: memset(sbp, 0, sizeof(*sbp));
984 return (FTS_NS);
985 }
986
987 if (S_ISDIR(sbp->st_mode)) {
988 /*
989 * Set the device/inode. Used to find cycles and check for
990 * crossing mount points. Also remember the link count, used
991 * in fts_build to limit the number of stat calls. It is
992 * understood that these fields are only referenced if fts_info
993 * is set to FTS_D.
994 */
995 dev = p->fts_dev = sbp->st_dev;
996 ino = p->fts_ino = sbp->st_ino;
997 p->fts_nlink = sbp->st_nlink;
998
999 if (ISDOT(p->fts_name))
1000 return (FTS_DOT);
1001
1002 /*
1003 * Cycle detection is done by brute force when the directory
1004 * is first encountered. If the tree gets deep enough or the
1005 * number of symbolic links to directories is high enough,
1006 * something faster might be worthwhile.
1007 */
1008 for (t = p->fts_parent;
1009 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)
1010 if (ino == t->fts_ino && dev == t->fts_dev) {
1011 p->fts_cycle = t;
1012 return (FTS_DC);
1013 }
1014 return (FTS_D);
1015 }
1016 if (S_ISLNK(sbp->st_mode))
1017 return (FTS_SL);
1018 if (S_ISREG(sbp->st_mode))
1019 return (FTS_F);
1020 return (FTS_DEFAULT);
1021 }
1022
1023 static FTSENT *
1024 fts_sort(FTS *sp, FTSENT *head, size_t nitems)
1025 {
1026 FTSENT **ap, *p;
1027
1028 _DIAGASSERT(sp != NULL);
1029 _DIAGASSERT(head != NULL);
1030
1031 /*
1032 * Construct an array of pointers to the structures and call qsort(3).
1033 * Reassemble the array in the order returned by qsort. If unable to
1034 * sort for memory reasons, return the directory entries in their
1035 * current order. Allocate enough space for the current needs plus
1036 * 40 so don't realloc one entry at a time.
1037 */
1038 if (nitems > sp->fts_nitems) {
1039 FTSENT **new;
1040
1041 new = realloc(sp->fts_array, sizeof(FTSENT *) * (nitems + 40));
1042 if (new == 0)
1043 return (head);
1044 sp->fts_array = new;
1045 sp->fts_nitems = fts_nitems_truncate(nitems + 40);
1046 }
1047 for (ap = sp->fts_array, p = head; p; p = p->fts_link)
1048 *ap++ = p;
1049 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *),
1050 (int (*)(const void *, const void *))sp->fts_compar);
1051 for (head = *(ap = sp->fts_array); --nitems; ++ap)
1052 ap[0]->fts_link = ap[1];
1053 ap[0]->fts_link = NULL;
1054 return (head);
1055 }
1056
1057 static FTSENT *
1058 fts_alloc(FTS *sp, const char *name, size_t namelen)
1059 {
1060 FTSENT *p;
1061 #if defined(FTS_ALLOC_ALIGNED)
1062 size_t len;
1063 #endif
1064
1065 _DIAGASSERT(sp != NULL);
1066 _DIAGASSERT(name != NULL);
1067
1068 #if defined(FTS_ALLOC_ALIGNED)
1069 /*
1070 * The file name is a variable length array and no stat structure is
1071 * necessary if the user has set the nostat bit. Allocate the FTSENT
1072 * structure, the file name and the stat structure in one chunk, but
1073 * be careful that the stat structure is reasonably aligned. Since the
1074 * fts_name field is declared to be of size 1, the fts_name pointer is
1075 * namelen + 2 before the first possible address of the stat structure.
1076 */
1077 len = sizeof(FTSENT) + namelen;
1078 if (!ISSET(FTS_NOSTAT))
1079 len += sizeof(*(p->fts_statp)) + ALIGNBYTES;
1080 if ((p = malloc(len)) == NULL)
1081 return (NULL);
1082
1083 if (!ISSET(FTS_NOSTAT))
1084 p->fts_statp = (struct stat *)ALIGN(
1085 (unsigned long)(p->fts_name + namelen + 2));
1086 #else
1087 if ((p = malloc(sizeof(FTSENT) + namelen)) == NULL)
1088 return (NULL);
1089
1090 if (!ISSET(FTS_NOSTAT))
1091 if ((p->fts_statp = malloc(sizeof(*(p->fts_statp)))) == NULL) {
1092 free(p);
1093 return (NULL);
1094 }
1095 #endif
1096
1097 if (ISSET(FTS_NOSTAT))
1098 p->fts_statp = NULL;
1099
1100 /* Copy the name plus the trailing NULL. */
1101 memmove(p->fts_name, name, namelen + 1);
1102
1103 p->fts_namelen = ftsent_namelen_truncate(namelen);
1104 p->fts_path = sp->fts_path;
1105 p->fts_errno = 0;
1106 p->fts_flags = 0;
1107 p->fts_instr = FTS_NOINSTR;
1108 p->fts_number = 0;
1109 p->fts_pointer = NULL;
1110 return (p);
1111 }
1112
1113 static void
1114 fts_free(FTSENT *p)
1115 {
1116 #if !defined(FTS_ALLOC_ALIGNED)
1117 if (p->fts_statp)
1118 free(p->fts_statp);
1119 #endif
1120 free(p);
1121 }
1122
1123 static void
1124 fts_lfree(FTSENT *head)
1125 {
1126 FTSENT *p;
1127
1128 /* XXX: head may be NULL ? */
1129
1130 /* Free a linked list of structures. */
1131 while ((p = head) != NULL) {
1132 head = head->fts_link;
1133 fts_free(p);
1134 }
1135 }
1136
1137 static size_t
1138 fts_pow2(size_t x)
1139 {
1140
1141 x--;
1142 x |= x>>1;
1143 x |= x>>2;
1144 x |= x>>4;
1145 x |= x>>8;
1146 x |= x>>16;
1147 #if LONG_BIT > 32
1148 x |= x>>32;
1149 #endif
1150 #if LONG_BIT > 64
1151 x |= x>>64;
1152 #endif
1153 x++;
1154 return (x);
1155 }
1156
1157 /*
1158 * Allow essentially unlimited paths; find, rm, ls should all work on any tree.
1159 * Most systems will allow creation of paths much longer than MAXPATHLEN, even
1160 * though the kernel won't resolve them. Round up the new size to a power of 2,
1161 * so we don't realloc the path 2 bytes at a time.
1162 */
1163 static int
1164 fts_palloc(FTS *sp, size_t size)
1165 {
1166 char *new;
1167
1168 _DIAGASSERT(sp != NULL);
1169
1170 #ifdef __FTS_COMPAT_LENGTH
1171 /* Protect against fts_pathlen overflow. */
1172 if (size > USHRT_MAX + 1) {
1173 errno = ENAMETOOLONG;
1174 return (1);
1175 }
1176 #endif
1177 size = fts_pow2(size);
1178 new = realloc(sp->fts_path, size);
1179 if (new == 0)
1180 return (1);
1181 sp->fts_path = new;
1182 sp->fts_pathlen = fts_pathlen_truncate(size);
1183 return (0);
1184 }
1185
1186 /*
1187 * When the path is realloc'd, have to fix all of the pointers in structures
1188 * already returned.
1189 */
1190 static void
1191 fts_padjust(FTS *sp, FTSENT *head)
1192 {
1193 FTSENT *p;
1194 char *addr;
1195
1196 _DIAGASSERT(sp != NULL);
1197
1198 #define ADJUST(p) do { \
1199 if ((p)->fts_accpath != (p)->fts_name) \
1200 (p)->fts_accpath = \
1201 addr + ((p)->fts_accpath - (p)->fts_path); \
1202 (p)->fts_path = addr; \
1203 } while (/*CONSTCOND*/0)
1204
1205 addr = sp->fts_path;
1206
1207 /* Adjust the current set of children. */
1208 for (p = sp->fts_child; p; p = p->fts_link)
1209 ADJUST(p);
1210
1211 /* Adjust the rest of the tree, including the current level. */
1212 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {
1213 ADJUST(p);
1214 p = p->fts_link ? p->fts_link : p->fts_parent;
1215 }
1216 }
1217
1218 static size_t
1219 fts_maxarglen(char * const *argv)
1220 {
1221 size_t len, max;
1222
1223 _DIAGASSERT(argv != NULL);
1224
1225 for (max = 0; *argv; ++argv)
1226 if ((len = strlen(*argv)) > max)
1227 max = len;
1228 return (max + 1);
1229 }
1230
1231 /*
1232 * Change to dir specified by fd or p->fts_accpath without getting
1233 * tricked by someone changing the world out from underneath us.
1234 * Assumes p->fts_dev and p->fts_ino are filled in.
1235 */
1236 static int
1237 fts_safe_changedir(const FTS *sp, const FTSENT *p, int fd, const char *path)
1238 {
1239 int oldfd = fd, ret = -1;
1240 struct stat sb;
1241
1242 if (ISSET(FTS_NOCHDIR))
1243 return 0;
1244
1245 if (oldfd < 0 && (path == NULL || (fd = open(path, O_RDONLY)) == -1))
1246 return -1;
1247
1248 if (fstat(fd, &sb) == -1)
1249 goto bail;
1250
1251 if (sb.st_ino != p->fts_ino || sb.st_dev != p->fts_dev) {
1252 errno = ENOENT;
1253 goto bail;
1254 }
1255
1256 ret = fchdir(fd);
1257
1258 bail:
1259 if (oldfd < 0) {
1260 int save_errno = errno;
1261 (void)close(fd);
1262 errno = save_errno;
1263 }
1264 return ret;
1265 }