1 | /* File tree walker functions. |
2 | Copyright (C) 1996-2019 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. |
5 | |
6 | The GNU C Library is free software; you can redistribute it and/or |
7 | modify it under the terms of the GNU Lesser General Public |
8 | License as published by the Free Software Foundation; either |
9 | version 2.1 of the License, or (at your option) any later version. |
10 | |
11 | The GNU C Library is distributed in the hope that it will be useful, |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | Lesser General Public License for more details. |
15 | |
16 | You should have received a copy of the GNU Lesser General Public |
17 | License along with the GNU C Library; if not, see |
18 | <http://www.gnu.org/licenses/>. */ |
19 | |
20 | #ifdef HAVE_CONFIG_H |
21 | # include <config.h> |
22 | #endif |
23 | |
24 | #if __GNUC__ |
25 | # define alloca __builtin_alloca |
26 | #else |
27 | # if HAVE_ALLOCA_H |
28 | # include <alloca.h> |
29 | # else |
30 | # ifdef _AIX |
31 | # pragma alloca |
32 | # else |
33 | char *alloca (); |
34 | # endif |
35 | # endif |
36 | #endif |
37 | |
38 | #ifdef _LIBC |
39 | # include <dirent.h> |
40 | # define NAMLEN(dirent) _D_EXACT_NAMLEN (dirent) |
41 | #else |
42 | # if HAVE_DIRENT_H |
43 | # include <dirent.h> |
44 | # define NAMLEN(dirent) strlen ((dirent)->d_name) |
45 | # else |
46 | # define dirent direct |
47 | # define NAMLEN(dirent) (dirent)->d_namlen |
48 | # if HAVE_SYS_NDIR_H |
49 | # include <sys/ndir.h> |
50 | # endif |
51 | # if HAVE_SYS_DIR_H |
52 | # include <sys/dir.h> |
53 | # endif |
54 | # if HAVE_NDIR_H |
55 | # include <ndir.h> |
56 | # endif |
57 | # endif |
58 | #endif |
59 | |
60 | #include <errno.h> |
61 | #include <fcntl.h> |
62 | #include <ftw.h> |
63 | #include <limits.h> |
64 | #include <search.h> |
65 | #include <stdlib.h> |
66 | #include <string.h> |
67 | #include <unistd.h> |
68 | #include <not-cancel.h> |
69 | #include <sys/param.h> |
70 | #ifdef _LIBC |
71 | # include <include/sys/stat.h> |
72 | #else |
73 | # include <sys/stat.h> |
74 | #endif |
75 | |
76 | #if ! _LIBC && !HAVE_DECL_STPCPY && !defined stpcpy |
77 | char *stpcpy (); |
78 | #endif |
79 | |
80 | #if ! _LIBC && ! defined HAVE_MEMPCPY && ! defined mempcpy |
81 | /* Be CAREFUL that there are no side effects in N. */ |
82 | # define mempcpy(D, S, N) ((void *) ((char *) memcpy (D, S, N) + (N))) |
83 | #endif |
84 | |
85 | /* #define NDEBUG 1 */ |
86 | #include <assert.h> |
87 | |
88 | #ifndef _LIBC |
89 | # undef __chdir |
90 | # define __chdir chdir |
91 | # undef __closedir |
92 | # define __closedir closedir |
93 | # undef __fchdir |
94 | # define __fchdir fchdir |
95 | # undef __getcwd |
96 | # define __getcwd(P, N) xgetcwd () |
97 | extern char *xgetcwd (void); |
98 | # undef __mempcpy |
99 | # define __mempcpy mempcpy |
100 | # undef __opendir |
101 | # define __opendir opendir |
102 | # undef __readdir64 |
103 | # define __readdir64 readdir |
104 | # undef __stpcpy |
105 | # define __stpcpy stpcpy |
106 | # undef __tdestroy |
107 | # define __tdestroy tdestroy |
108 | # undef __tfind |
109 | # define __tfind tfind |
110 | # undef __tsearch |
111 | # define __tsearch tsearch |
112 | # undef dirent64 |
113 | # define dirent64 dirent |
114 | # undef MAX |
115 | # define MAX(a, b) ((a) > (b) ? (a) : (b)) |
116 | #endif |
117 | |
118 | /* Arrange to make lstat calls go through the wrapper function |
119 | on systems with an lstat function that does not dereference symlinks |
120 | that are specified with a trailing slash. */ |
121 | #if ! _LIBC && ! LSTAT_FOLLOWS_SLASHED_SYMLINK |
122 | int rpl_lstat (const char *, struct stat *); |
123 | # undef lstat |
124 | # define lstat(Name, Stat_buf) rpl_lstat(Name, Stat_buf) |
125 | #endif |
126 | |
127 | #ifndef __set_errno |
128 | # define __set_errno(Val) errno = (Val) |
129 | #endif |
130 | |
131 | /* Support for the LFS API version. */ |
132 | #ifndef FTW_NAME |
133 | # define FTW_NAME ftw |
134 | # define NFTW_NAME nftw |
135 | # define NFTW_OLD_NAME __old_nftw |
136 | # define NFTW_NEW_NAME __new_nftw |
137 | # define INO_T ino_t |
138 | # define STAT stat |
139 | # ifdef _LIBC |
140 | # define LXSTAT __lxstat |
141 | # define XSTAT __xstat |
142 | # define FXSTATAT __fxstatat |
143 | # else |
144 | # define LXSTAT(V,f,sb) lstat (f,sb) |
145 | # define XSTAT(V,f,sb) stat (f,sb) |
146 | # define FXSTATAT(V,d,f,sb,m) fstatat (d, f, sb, m) |
147 | # endif |
148 | # define FTW_FUNC_T __ftw_func_t |
149 | # define NFTW_FUNC_T __nftw_func_t |
150 | #endif |
151 | |
152 | /* We define PATH_MAX if the system does not provide a definition. |
153 | This does not artificially limit any operation. PATH_MAX is simply |
154 | used as a guesstimate for the expected maximal path length. |
155 | Buffers will be enlarged if necessary. */ |
156 | #ifndef PATH_MAX |
157 | # define PATH_MAX 1024 |
158 | #endif |
159 | |
160 | struct dir_data |
161 | { |
162 | DIR *stream; |
163 | int streamfd; |
164 | char *content; |
165 | }; |
166 | |
167 | struct known_object |
168 | { |
169 | dev_t dev; |
170 | INO_T ino; |
171 | }; |
172 | |
173 | struct ftw_data |
174 | { |
175 | /* Array with pointers to open directory streams. */ |
176 | struct dir_data **dirstreams; |
177 | size_t actdir; |
178 | size_t maxdir; |
179 | |
180 | /* Buffer containing name of currently processed object. */ |
181 | char *dirbuf; |
182 | size_t dirbufsize; |
183 | |
184 | /* Passed as fourth argument to `nftw' callback. The `base' member |
185 | tracks the content of the `dirbuf'. */ |
186 | struct FTW ftw; |
187 | |
188 | /* Flags passed to `nftw' function. 0 for `ftw'. */ |
189 | int flags; |
190 | |
191 | /* Conversion array for flag values. It is the identity mapping for |
192 | `nftw' calls, otherwise it maps the values to those known by |
193 | `ftw'. */ |
194 | const int *cvt_arr; |
195 | |
196 | /* Callback function. We always use the `nftw' form. */ |
197 | NFTW_FUNC_T func; |
198 | |
199 | /* Device of starting point. Needed for FTW_MOUNT. */ |
200 | dev_t dev; |
201 | |
202 | /* Data structure for keeping fingerprints of already processed |
203 | object. This is needed when not using FTW_PHYS. */ |
204 | void *known_objects; |
205 | }; |
206 | |
207 | |
208 | /* Internally we use the FTW_* constants used for `nftw'. When invoked |
209 | as `ftw', map each flag to the subset of values used by `ftw'. */ |
210 | static const int nftw_arr[] = |
211 | { |
212 | FTW_F, FTW_D, FTW_DNR, FTW_NS, FTW_SL, FTW_DP, FTW_SLN |
213 | }; |
214 | |
215 | static const int ftw_arr[] = |
216 | { |
217 | FTW_F, FTW_D, FTW_DNR, FTW_NS, FTW_F, FTW_D, FTW_NS |
218 | }; |
219 | |
220 | |
221 | /* Forward declarations of local functions. */ |
222 | static int ftw_dir (struct ftw_data *data, struct STAT *st, |
223 | struct dir_data *old_dir); |
224 | |
225 | |
226 | static int |
227 | object_compare (const void *p1, const void *p2) |
228 | { |
229 | /* We don't need a sophisticated and useful comparison. We are only |
230 | interested in equality. However, we must be careful not to |
231 | accidentally compare `holes' in the structure. */ |
232 | const struct known_object *kp1 = p1, *kp2 = p2; |
233 | int cmp1; |
234 | cmp1 = (kp1->ino > kp2->ino) - (kp1->ino < kp2->ino); |
235 | if (cmp1 != 0) |
236 | return cmp1; |
237 | return (kp1->dev > kp2->dev) - (kp1->dev < kp2->dev); |
238 | } |
239 | |
240 | |
241 | static int |
242 | add_object (struct ftw_data *data, struct STAT *st) |
243 | { |
244 | struct known_object *newp = malloc (sizeof (struct known_object)); |
245 | if (newp == NULL) |
246 | return -1; |
247 | newp->dev = st->st_dev; |
248 | newp->ino = st->st_ino; |
249 | return __tsearch (newp, &data->known_objects, object_compare) ? 0 : -1; |
250 | } |
251 | |
252 | |
253 | static inline int |
254 | find_object (struct ftw_data *data, struct STAT *st) |
255 | { |
256 | struct known_object obj; |
257 | obj.dev = st->st_dev; |
258 | obj.ino = st->st_ino; |
259 | return __tfind (&obj, &data->known_objects, object_compare) != NULL; |
260 | } |
261 | |
262 | |
263 | static inline int |
264 | __attribute ((always_inline)) |
265 | open_dir_stream (int *dfdp, struct ftw_data *data, struct dir_data *dirp) |
266 | { |
267 | int result = 0; |
268 | |
269 | if (data->dirstreams[data->actdir] != NULL) |
270 | { |
271 | /* Oh, oh. We must close this stream. Get all remaining |
272 | entries and store them as a list in the `content' member of |
273 | the `struct dir_data' variable. */ |
274 | size_t bufsize = 1024; |
275 | char *buf = malloc (bufsize); |
276 | |
277 | if (buf == NULL) |
278 | result = -1; |
279 | else |
280 | { |
281 | DIR *st = data->dirstreams[data->actdir]->stream; |
282 | struct dirent64 *d; |
283 | size_t actsize = 0; |
284 | |
285 | while ((d = __readdir64 (st)) != NULL) |
286 | { |
287 | size_t this_len = NAMLEN (d); |
288 | if (actsize + this_len + 2 >= bufsize) |
289 | { |
290 | char *newp; |
291 | bufsize += MAX (1024, 2 * this_len); |
292 | newp = (char *) realloc (buf, bufsize); |
293 | if (newp == NULL) |
294 | { |
295 | /* No more memory. */ |
296 | int save_err = errno; |
297 | free (buf); |
298 | __set_errno (save_err); |
299 | return -1; |
300 | } |
301 | buf = newp; |
302 | } |
303 | |
304 | *((char *) __mempcpy (buf + actsize, d->d_name, this_len)) |
305 | = '\0'; |
306 | actsize += this_len + 1; |
307 | } |
308 | |
309 | /* Terminate the list with an additional NUL byte. */ |
310 | buf[actsize++] = '\0'; |
311 | |
312 | /* Shrink the buffer to what we actually need. */ |
313 | data->dirstreams[data->actdir]->content = realloc (buf, actsize); |
314 | if (data->dirstreams[data->actdir]->content == NULL) |
315 | { |
316 | int save_err = errno; |
317 | free (buf); |
318 | __set_errno (save_err); |
319 | result = -1; |
320 | } |
321 | else |
322 | { |
323 | __closedir (st); |
324 | data->dirstreams[data->actdir]->stream = NULL; |
325 | data->dirstreams[data->actdir]->streamfd = -1; |
326 | data->dirstreams[data->actdir] = NULL; |
327 | } |
328 | } |
329 | } |
330 | |
331 | /* Open the new stream. */ |
332 | if (result == 0) |
333 | { |
334 | assert (data->dirstreams[data->actdir] == NULL); |
335 | |
336 | if (dfdp != NULL && *dfdp != -1) |
337 | { |
338 | int fd = __openat64_nocancel (*dfdp, data->dirbuf + data->ftw.base, |
339 | O_RDONLY | O_DIRECTORY | O_NDELAY); |
340 | dirp->stream = NULL; |
341 | if (fd != -1 && (dirp->stream = __fdopendir (fd)) == NULL) |
342 | __close_nocancel_nostatus (fd); |
343 | } |
344 | else |
345 | { |
346 | const char *name; |
347 | |
348 | if (data->flags & FTW_CHDIR) |
349 | { |
350 | name = data->dirbuf + data->ftw.base; |
351 | if (name[0] == '\0') |
352 | name = "." ; |
353 | } |
354 | else |
355 | name = data->dirbuf; |
356 | |
357 | dirp->stream = __opendir (name); |
358 | } |
359 | |
360 | if (dirp->stream == NULL) |
361 | result = -1; |
362 | else |
363 | { |
364 | dirp->streamfd = __dirfd (dirp->stream); |
365 | dirp->content = NULL; |
366 | data->dirstreams[data->actdir] = dirp; |
367 | |
368 | if (++data->actdir == data->maxdir) |
369 | data->actdir = 0; |
370 | } |
371 | } |
372 | |
373 | return result; |
374 | } |
375 | |
376 | |
377 | static int |
378 | process_entry (struct ftw_data *data, struct dir_data *dir, const char *name, |
379 | size_t namlen, int d_type) |
380 | { |
381 | struct STAT st; |
382 | int result = 0; |
383 | int flag = 0; |
384 | size_t new_buflen; |
385 | |
386 | if (name[0] == '.' && (name[1] == '\0' |
387 | || (name[1] == '.' && name[2] == '\0'))) |
388 | /* Don't process the "." and ".." entries. */ |
389 | return 0; |
390 | |
391 | new_buflen = data->ftw.base + namlen + 2; |
392 | if (data->dirbufsize < new_buflen) |
393 | { |
394 | /* Enlarge the buffer. */ |
395 | char *newp; |
396 | |
397 | data->dirbufsize = 2 * new_buflen; |
398 | newp = (char *) realloc (data->dirbuf, data->dirbufsize); |
399 | if (newp == NULL) |
400 | return -1; |
401 | data->dirbuf = newp; |
402 | } |
403 | |
404 | *((char *) __mempcpy (data->dirbuf + data->ftw.base, name, namlen)) = '\0'; |
405 | |
406 | int statres; |
407 | if (dir->streamfd != -1) |
408 | statres = FXSTATAT (_STAT_VER, dir->streamfd, name, &st, |
409 | (data->flags & FTW_PHYS) ? AT_SYMLINK_NOFOLLOW : 0); |
410 | else |
411 | { |
412 | if ((data->flags & FTW_CHDIR) == 0) |
413 | name = data->dirbuf; |
414 | |
415 | statres = ((data->flags & FTW_PHYS) |
416 | ? LXSTAT (_STAT_VER, name, &st) |
417 | : XSTAT (_STAT_VER, name, &st)); |
418 | } |
419 | |
420 | if (statres < 0) |
421 | { |
422 | if (errno != EACCES && errno != ENOENT) |
423 | result = -1; |
424 | else if (data->flags & FTW_PHYS) |
425 | flag = FTW_NS; |
426 | else if (d_type == DT_LNK) |
427 | flag = FTW_SLN; |
428 | else |
429 | { |
430 | if (dir->streamfd != -1) |
431 | statres = FXSTATAT (_STAT_VER, dir->streamfd, name, &st, |
432 | AT_SYMLINK_NOFOLLOW); |
433 | else |
434 | statres = LXSTAT (_STAT_VER, name, &st); |
435 | if (statres == 0 && S_ISLNK (st.st_mode)) |
436 | flag = FTW_SLN; |
437 | else |
438 | flag = FTW_NS; |
439 | } |
440 | } |
441 | else |
442 | { |
443 | if (S_ISDIR (st.st_mode)) |
444 | flag = FTW_D; |
445 | else if (S_ISLNK (st.st_mode)) |
446 | flag = FTW_SL; |
447 | else |
448 | flag = FTW_F; |
449 | } |
450 | |
451 | if (result == 0 |
452 | && (flag == FTW_NS |
453 | || !(data->flags & FTW_MOUNT) || st.st_dev == data->dev)) |
454 | { |
455 | if (flag == FTW_D) |
456 | { |
457 | if ((data->flags & FTW_PHYS) |
458 | || (!find_object (data, &st) |
459 | /* Remember the object. */ |
460 | && (result = add_object (data, &st)) == 0)) |
461 | result = ftw_dir (data, &st, dir); |
462 | } |
463 | else |
464 | result = (*data->func) (data->dirbuf, &st, data->cvt_arr[flag], |
465 | &data->ftw); |
466 | } |
467 | |
468 | if ((data->flags & FTW_ACTIONRETVAL) && result == FTW_SKIP_SUBTREE) |
469 | result = 0; |
470 | |
471 | return result; |
472 | } |
473 | |
474 | |
475 | static int |
476 | __attribute ((noinline)) |
477 | ftw_dir (struct ftw_data *data, struct STAT *st, struct dir_data *old_dir) |
478 | { |
479 | struct dir_data dir; |
480 | struct dirent64 *d; |
481 | int previous_base = data->ftw.base; |
482 | int result; |
483 | char *startp; |
484 | |
485 | /* Open the stream for this directory. This might require that |
486 | another stream has to be closed. */ |
487 | result = open_dir_stream (old_dir == NULL ? NULL : &old_dir->streamfd, |
488 | data, &dir); |
489 | if (result != 0) |
490 | { |
491 | if (errno == EACCES) |
492 | /* We cannot read the directory. Signal this with a special flag. */ |
493 | result = (*data->func) (data->dirbuf, st, FTW_DNR, &data->ftw); |
494 | |
495 | return result; |
496 | } |
497 | |
498 | /* First, report the directory (if not depth-first). */ |
499 | if (!(data->flags & FTW_DEPTH)) |
500 | { |
501 | result = (*data->func) (data->dirbuf, st, FTW_D, &data->ftw); |
502 | if (result != 0) |
503 | { |
504 | int save_err; |
505 | fail: |
506 | save_err = errno; |
507 | __closedir (dir.stream); |
508 | dir.streamfd = -1; |
509 | __set_errno (save_err); |
510 | |
511 | if (data->actdir-- == 0) |
512 | data->actdir = data->maxdir - 1; |
513 | data->dirstreams[data->actdir] = NULL; |
514 | return result; |
515 | } |
516 | } |
517 | |
518 | /* If necessary, change to this directory. */ |
519 | if (data->flags & FTW_CHDIR) |
520 | { |
521 | if (__fchdir (__dirfd (dir.stream)) < 0) |
522 | { |
523 | result = -1; |
524 | goto fail; |
525 | } |
526 | } |
527 | |
528 | /* Next, update the `struct FTW' information. */ |
529 | ++data->ftw.level; |
530 | startp = __rawmemchr (data->dirbuf, '\0'); |
531 | /* There always must be a directory name. */ |
532 | assert (startp != data->dirbuf); |
533 | if (startp[-1] != '/') |
534 | *startp++ = '/'; |
535 | data->ftw.base = startp - data->dirbuf; |
536 | |
537 | while (dir.stream != NULL && (d = __readdir64 (dir.stream)) != NULL) |
538 | { |
539 | int d_type = DT_UNKNOWN; |
540 | #ifdef _DIRENT_HAVE_D_TYPE |
541 | d_type = d->d_type; |
542 | #endif |
543 | result = process_entry (data, &dir, d->d_name, NAMLEN (d), d_type); |
544 | if (result != 0) |
545 | break; |
546 | } |
547 | |
548 | if (dir.stream != NULL) |
549 | { |
550 | /* The stream is still open. I.e., we did not need more |
551 | descriptors. Simply close the stream now. */ |
552 | int save_err = errno; |
553 | |
554 | assert (dir.content == NULL); |
555 | |
556 | __closedir (dir.stream); |
557 | dir.streamfd = -1; |
558 | __set_errno (save_err); |
559 | |
560 | if (data->actdir-- == 0) |
561 | data->actdir = data->maxdir - 1; |
562 | data->dirstreams[data->actdir] = NULL; |
563 | } |
564 | else |
565 | { |
566 | int save_err; |
567 | char *runp = dir.content; |
568 | |
569 | while (result == 0 && *runp != '\0') |
570 | { |
571 | char *endp = strchr (runp, '\0'); |
572 | |
573 | // XXX Should store the d_type values as well?! |
574 | result = process_entry (data, &dir, runp, endp - runp, DT_UNKNOWN); |
575 | |
576 | runp = endp + 1; |
577 | } |
578 | |
579 | save_err = errno; |
580 | free (dir.content); |
581 | __set_errno (save_err); |
582 | } |
583 | |
584 | if ((data->flags & FTW_ACTIONRETVAL) && result == FTW_SKIP_SIBLINGS) |
585 | result = 0; |
586 | |
587 | /* Prepare the return, revert the `struct FTW' information. */ |
588 | data->dirbuf[data->ftw.base - 1] = '\0'; |
589 | --data->ftw.level; |
590 | data->ftw.base = previous_base; |
591 | |
592 | /* Finally, if we process depth-first report the directory. */ |
593 | if (result == 0 && (data->flags & FTW_DEPTH)) |
594 | result = (*data->func) (data->dirbuf, st, FTW_DP, &data->ftw); |
595 | |
596 | if (old_dir |
597 | && (data->flags & FTW_CHDIR) |
598 | && (result == 0 |
599 | || ((data->flags & FTW_ACTIONRETVAL) |
600 | && (result != -1 && result != FTW_STOP)))) |
601 | { |
602 | /* Change back to the parent directory. */ |
603 | int done = 0; |
604 | if (old_dir->stream != NULL) |
605 | if (__fchdir (__dirfd (old_dir->stream)) == 0) |
606 | done = 1; |
607 | |
608 | if (!done) |
609 | { |
610 | if (data->ftw.base == 1) |
611 | { |
612 | if (__chdir ("/" ) < 0) |
613 | result = -1; |
614 | } |
615 | else |
616 | if (__chdir (".." ) < 0) |
617 | result = -1; |
618 | } |
619 | } |
620 | |
621 | return result; |
622 | } |
623 | |
624 | |
625 | static int |
626 | __attribute ((noinline)) |
627 | ftw_startup (const char *dir, int is_nftw, void *func, int descriptors, |
628 | int flags) |
629 | { |
630 | struct ftw_data data; |
631 | struct STAT st; |
632 | int result = 0; |
633 | int save_err; |
634 | int cwdfd = -1; |
635 | char *cwd = NULL; |
636 | char *cp; |
637 | |
638 | /* First make sure the parameters are reasonable. */ |
639 | if (dir[0] == '\0') |
640 | { |
641 | __set_errno (ENOENT); |
642 | return -1; |
643 | } |
644 | |
645 | data.maxdir = descriptors < 1 ? 1 : descriptors; |
646 | data.actdir = 0; |
647 | data.dirstreams = (struct dir_data **) alloca (data.maxdir |
648 | * sizeof (struct dir_data *)); |
649 | memset (data.dirstreams, '\0', data.maxdir * sizeof (struct dir_data *)); |
650 | |
651 | /* PATH_MAX is always defined when we get here. */ |
652 | data.dirbufsize = MAX (2 * strlen (dir), PATH_MAX); |
653 | data.dirbuf = (char *) malloc (data.dirbufsize); |
654 | if (data.dirbuf == NULL) |
655 | return -1; |
656 | cp = __stpcpy (data.dirbuf, dir); |
657 | /* Strip trailing slashes. */ |
658 | while (cp > data.dirbuf + 1 && cp[-1] == '/') |
659 | --cp; |
660 | *cp = '\0'; |
661 | |
662 | data.ftw.level = 0; |
663 | |
664 | /* Find basename. */ |
665 | while (cp > data.dirbuf && cp[-1] != '/') |
666 | --cp; |
667 | data.ftw.base = cp - data.dirbuf; |
668 | |
669 | data.flags = flags; |
670 | |
671 | /* This assignment might seem to be strange but it is what we want. |
672 | The trick is that the first three arguments to the `ftw' and |
673 | `nftw' callback functions are equal. Therefore we can call in |
674 | every case the callback using the format of the `nftw' version |
675 | and get the correct result since the stack layout for a function |
676 | call in C allows this. */ |
677 | data.func = (NFTW_FUNC_T) func; |
678 | |
679 | /* Since we internally use the complete set of FTW_* values we need |
680 | to reduce the value range before calling a `ftw' callback. */ |
681 | data.cvt_arr = is_nftw ? nftw_arr : ftw_arr; |
682 | |
683 | /* No object known so far. */ |
684 | data.known_objects = NULL; |
685 | |
686 | /* Now go to the directory containing the initial file/directory. */ |
687 | if (flags & FTW_CHDIR) |
688 | { |
689 | /* We have to be able to go back to the current working |
690 | directory. The best way to do this is to use a file |
691 | descriptor. */ |
692 | cwdfd = __open ("." , O_RDONLY | O_DIRECTORY); |
693 | if (cwdfd == -1) |
694 | { |
695 | /* Try getting the directory name. This can be needed if |
696 | the current directory is executable but not readable. */ |
697 | if (errno == EACCES) |
698 | /* GNU extension ahead. */ |
699 | cwd = __getcwd (NULL, 0); |
700 | |
701 | if (cwd == NULL) |
702 | goto out_fail; |
703 | } |
704 | else if (data.maxdir > 1) |
705 | /* Account for the file descriptor we use here. */ |
706 | --data.maxdir; |
707 | |
708 | if (data.ftw.base > 0) |
709 | { |
710 | /* Change to the directory the file is in. In data.dirbuf |
711 | we have a writable copy of the file name. Just NUL |
712 | terminate it for now and change the directory. */ |
713 | if (data.ftw.base == 1) |
714 | /* I.e., the file is in the root directory. */ |
715 | result = __chdir ("/" ); |
716 | else |
717 | { |
718 | char ch = data.dirbuf[data.ftw.base - 1]; |
719 | data.dirbuf[data.ftw.base - 1] = '\0'; |
720 | result = __chdir (data.dirbuf); |
721 | data.dirbuf[data.ftw.base - 1] = ch; |
722 | } |
723 | } |
724 | } |
725 | |
726 | /* Get stat info for start directory. */ |
727 | if (result == 0) |
728 | { |
729 | const char *name; |
730 | |
731 | if (data.flags & FTW_CHDIR) |
732 | { |
733 | name = data.dirbuf + data.ftw.base; |
734 | if (name[0] == '\0') |
735 | name = "." ; |
736 | } |
737 | else |
738 | name = data.dirbuf; |
739 | |
740 | if (((flags & FTW_PHYS) |
741 | ? LXSTAT (_STAT_VER, name, &st) |
742 | : XSTAT (_STAT_VER, name, &st)) < 0) |
743 | { |
744 | if (!(flags & FTW_PHYS) |
745 | && errno == ENOENT |
746 | && LXSTAT (_STAT_VER, name, &st) == 0 |
747 | && S_ISLNK (st.st_mode)) |
748 | result = (*data.func) (data.dirbuf, &st, data.cvt_arr[FTW_SLN], |
749 | &data.ftw); |
750 | else |
751 | /* No need to call the callback since we cannot say anything |
752 | about the object. */ |
753 | result = -1; |
754 | } |
755 | else |
756 | { |
757 | if (S_ISDIR (st.st_mode)) |
758 | { |
759 | /* Remember the device of the initial directory in case |
760 | FTW_MOUNT is given. */ |
761 | data.dev = st.st_dev; |
762 | |
763 | /* We know this directory now. */ |
764 | if (!(flags & FTW_PHYS)) |
765 | result = add_object (&data, &st); |
766 | |
767 | if (result == 0) |
768 | result = ftw_dir (&data, &st, NULL); |
769 | } |
770 | else |
771 | { |
772 | int flag = S_ISLNK (st.st_mode) ? FTW_SL : FTW_F; |
773 | |
774 | result = (*data.func) (data.dirbuf, &st, data.cvt_arr[flag], |
775 | &data.ftw); |
776 | } |
777 | } |
778 | |
779 | if ((flags & FTW_ACTIONRETVAL) |
780 | && (result == FTW_SKIP_SUBTREE || result == FTW_SKIP_SIBLINGS)) |
781 | result = 0; |
782 | } |
783 | |
784 | /* Return to the start directory (if necessary). */ |
785 | if (cwdfd != -1) |
786 | { |
787 | int save_err = errno; |
788 | __fchdir (cwdfd); |
789 | __close_nocancel_nostatus (cwdfd); |
790 | __set_errno (save_err); |
791 | } |
792 | else if (cwd != NULL) |
793 | { |
794 | int save_err = errno; |
795 | __chdir (cwd); |
796 | free (cwd); |
797 | __set_errno (save_err); |
798 | } |
799 | |
800 | /* Free all memory. */ |
801 | out_fail: |
802 | save_err = errno; |
803 | __tdestroy (data.known_objects, free); |
804 | free (data.dirbuf); |
805 | __set_errno (save_err); |
806 | |
807 | return result; |
808 | } |
809 | |
810 | |
811 | |
812 | /* Entry points. */ |
813 | |
814 | int |
815 | FTW_NAME (const char *path, FTW_FUNC_T func, int descriptors) |
816 | { |
817 | return ftw_startup (path, 0, func, descriptors, 0); |
818 | } |
819 | |
820 | #ifndef _LIBC |
821 | int |
822 | NFTW_NAME (const char *path, NFTW_FUNC_T func, int descriptors, int flags) |
823 | { |
824 | return ftw_startup (path, 1, func, descriptors, flags); |
825 | } |
826 | #else |
827 | |
828 | # include <shlib-compat.h> |
829 | |
830 | int NFTW_NEW_NAME (const char *, NFTW_FUNC_T, int, int); |
831 | |
832 | int |
833 | NFTW_NEW_NAME (const char *path, NFTW_FUNC_T func, int descriptors, int flags) |
834 | { |
835 | if (flags |
836 | & ~(FTW_PHYS | FTW_MOUNT | FTW_CHDIR | FTW_DEPTH | FTW_ACTIONRETVAL)) |
837 | { |
838 | __set_errno (EINVAL); |
839 | return -1; |
840 | } |
841 | return ftw_startup (path, 1, func, descriptors, flags); |
842 | } |
843 | |
844 | versioned_symbol (libc, NFTW_NEW_NAME, NFTW_NAME, GLIBC_2_3_3); |
845 | |
846 | # if SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_3_3) |
847 | |
848 | /* Older nftw* version just ignored all unknown flags. */ |
849 | |
850 | int NFTW_OLD_NAME (const char *, NFTW_FUNC_T, int, int); |
851 | |
852 | int |
853 | attribute_compat_text_section |
854 | NFTW_OLD_NAME (const char *path, NFTW_FUNC_T func, int descriptors, int flags) |
855 | { |
856 | flags &= (FTW_PHYS | FTW_MOUNT | FTW_CHDIR | FTW_DEPTH); |
857 | return ftw_startup (path, 1, func, descriptors, flags); |
858 | } |
859 | |
860 | compat_symbol (libc, NFTW_OLD_NAME, NFTW_NAME, GLIBC_2_1); |
861 | # endif |
862 | #endif |
863 | |