1 /* File tree walker functions.
2    Copyright (C) 1996-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library 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 GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #ifdef HAVE_CONFIG_H
20 # include <config.h>
21 #endif
22 
23 #if __GNUC__
24 # define alloca __builtin_alloca
25 #else
26 # if HAVE_ALLOCA_H
27 #  include <alloca.h>
28 # else
29 #  ifdef _AIX
30  #  pragma alloca
31 #  else
32 char *alloca ();
33 #  endif
34 # endif
35 #endif
36 
37 #ifdef _LIBC
38 # include <dirent.h>
39 # define NAMLEN(dirent) _D_EXACT_NAMLEN (dirent)
40 #else
41 # if HAVE_DIRENT_H
42 #  include <dirent.h>
43 #  define NAMLEN(dirent) strlen ((dirent)->d_name)
44 # else
45 #  define dirent direct
46 #  define NAMLEN(dirent) (dirent)->d_namlen
47 #  if HAVE_SYS_NDIR_H
48 #   include <sys/ndir.h>
49 #  endif
50 #  if HAVE_SYS_DIR_H
51 #   include <sys/dir.h>
52 #  endif
53 #  if HAVE_NDIR_H
54 #   include <ndir.h>
55 #  endif
56 # endif
57 #endif
58 
59 #include <errno.h>
60 #include <fcntl.h>
61 #include <ftw.h>
62 #include <limits.h>
63 #include <search.h>
64 #include <stdlib.h>
65 #include <string.h>
66 #include <unistd.h>
67 #include <not-cancel.h>
68 #include <sys/param.h>
69 #ifdef _LIBC
70 # include <include/sys/stat.h>
71 #else
72 # include <sys/stat.h>
73 #endif
74 
75 #if ! _LIBC && !HAVE_DECL_STPCPY && !defined stpcpy
76 char *stpcpy ();
77 #endif
78 
79 #if ! _LIBC && ! defined HAVE_MEMPCPY && ! defined mempcpy
80 /* Be CAREFUL that there are no side effects in N.  */
81 # define mempcpy(D, S, N) ((void *) ((char *) memcpy (D, S, N) + (N)))
82 #endif
83 
84 /* #define NDEBUG 1 */
85 #include <assert.h>
86 
87 #ifndef _LIBC
88 # undef __chdir
89 # define __chdir chdir
90 # undef __closedir
91 # define __closedir closedir
92 # undef __fchdir
93 # define __fchdir fchdir
94 # undef __getcwd
95 # define __getcwd(P, N) xgetcwd ()
96 extern char *xgetcwd (void);
97 # undef __mempcpy
98 # define __mempcpy mempcpy
99 # undef __opendir
100 # define __opendir opendir
101 # undef __readdir64
102 # define __readdir64 readdir
103 # undef __stpcpy
104 # define __stpcpy stpcpy
105 # undef __tdestroy
106 # define __tdestroy tdestroy
107 # undef __tfind
108 # define __tfind tfind
109 # undef __tsearch
110 # define __tsearch tsearch
111 # undef dirent64
112 # define dirent64 dirent
113 # undef MAX
114 # define MAX(a, b) ((a) > (b) ? (a) : (b))
115 #endif
116 
117 /* Arrange to make lstat calls go through the wrapper function
118    on systems with an lstat function that does not dereference symlinks
119    that are specified with a trailing slash.  */
120 #if ! _LIBC && ! LSTAT_FOLLOWS_SLASHED_SYMLINK
121 int rpl_lstat (const char *, struct stat *);
122 # undef lstat
123 # define lstat(Name, Stat_buf) rpl_lstat(Name, Stat_buf)
124 #endif
125 
126 #ifndef __set_errno
127 # define __set_errno(Val) errno = (Val)
128 #endif
129 
130 /* Support for the LFS API version.  */
131 #ifndef FTW_NAME
132 # define FTW_NAME ftw
133 # define NFTW_NAME nftw
134 # define NFTW_OLD_NAME __old_nftw
135 # define NFTW_NEW_NAME __new_nftw
136 # define INO_T ino_t
137 # define STRUCT_STAT stat
138 # ifdef _LIBC
139 #  define LSTAT __lstat
140 #  define STAT __stat
141 #  define FSTATAT __fstatat
142 # else
143 #  define LSTAT lstat
144 #  define XTAT stat
145 #  define FSTATAT fstatat
146 # endif
147 # define FTW_FUNC_T __ftw_func_t
148 # define NFTW_FUNC_T __nftw_func_t
149 #endif
150 
151 /* We define PATH_MAX if the system does not provide a definition.
152    This does not artificially limit any operation.  PATH_MAX is simply
153    used as a guesstimate for the expected maximal path length.
154    Buffers will be enlarged if necessary.  */
155 #ifndef PATH_MAX
156 # define PATH_MAX 1024
157 #endif
158 
159 struct dir_data
160 {
161   DIR *stream;
162   int streamfd;
163   char *content;
164 };
165 
166 struct known_object
167 {
168   dev_t dev;
169   INO_T ino;
170 };
171 
172 struct ftw_data
173 {
174   /* Array with pointers to open directory streams.  */
175   struct dir_data **dirstreams;
176   size_t actdir;
177   size_t maxdir;
178 
179   /* Buffer containing name of currently processed object.  */
180   char *dirbuf;
181   size_t dirbufsize;
182 
183   /* Passed as fourth argument to `nftw' callback.  The `base' member
184      tracks the content of the `dirbuf'.  */
185   struct FTW ftw;
186 
187   /* Flags passed to `nftw' function.  0 for `ftw'.  */
188   int flags;
189 
190   /* Conversion array for flag values.  It is the identity mapping for
191      `nftw' calls, otherwise it maps the values to those known by
192      `ftw'.  */
193   const int *cvt_arr;
194 
195   /* Callback function.  We always use the `nftw' form.  */
196   NFTW_FUNC_T func;
197 
198   /* Device of starting point.  Needed for FTW_MOUNT.  */
199   dev_t dev;
200 
201   /* Data structure for keeping fingerprints of already processed
202      object.  This is needed when not using FTW_PHYS.  */
203   void *known_objects;
204 };
205 
206 static bool
ftw_allocate(struct ftw_data * data,size_t newsize)207 ftw_allocate (struct ftw_data *data, size_t newsize)
208 {
209   void *newp = realloc (data->dirstreams, data->maxdir
210 					  * sizeof (struct dir_data *)
211 					  + newsize);
212   if (newp == NULL)
213     return false;
214   data->dirstreams = newp;
215   data->dirbufsize = newsize;
216   data->dirbuf = (char *) data->dirstreams
217 		 + data->maxdir * sizeof (struct dir_data *);
218   return true;
219 }
220 
221 /* Internally we use the FTW_* constants used for `nftw'.  When invoked
222    as `ftw', map each flag to the subset of values used by `ftw'.  */
223 static const int nftw_arr[] =
224 {
225   FTW_F, FTW_D, FTW_DNR, FTW_NS, FTW_SL, FTW_DP, FTW_SLN
226 };
227 
228 static const int ftw_arr[] =
229 {
230   FTW_F, FTW_D, FTW_DNR, FTW_NS, FTW_F, FTW_D, FTW_NS
231 };
232 
233 
234 /* Forward declarations of local functions.  */
235 static int ftw_dir (struct ftw_data *data, struct STRUCT_STAT *st,
236 		    struct dir_data *old_dir);
237 
238 
239 static int
object_compare(const void * p1,const void * p2)240 object_compare (const void *p1, const void *p2)
241 {
242   /* We don't need a sophisticated and useful comparison.  We are only
243      interested in equality.  However, we must be careful not to
244      accidentally compare `holes' in the structure.  */
245   const struct known_object *kp1 = p1, *kp2 = p2;
246   int cmp1;
247   cmp1 = (kp1->ino > kp2->ino) - (kp1->ino < kp2->ino);
248   if (cmp1 != 0)
249     return cmp1;
250   return (kp1->dev > kp2->dev) - (kp1->dev < kp2->dev);
251 }
252 
253 
254 static int
add_object(struct ftw_data * data,struct STRUCT_STAT * st)255 add_object (struct ftw_data *data, struct STRUCT_STAT *st)
256 {
257   struct known_object *newp = malloc (sizeof (struct known_object));
258   if (newp == NULL)
259     return -1;
260   newp->dev = st->st_dev;
261   newp->ino = st->st_ino;
262   return __tsearch (newp, &data->known_objects, object_compare) ? 0 : -1;
263 }
264 
265 
266 static inline int
find_object(struct ftw_data * data,struct STRUCT_STAT * st)267 find_object (struct ftw_data *data, struct STRUCT_STAT *st)
268 {
269   struct known_object obj;
270   obj.dev = st->st_dev;
271   obj.ino = st->st_ino;
272   return __tfind (&obj, &data->known_objects, object_compare) != NULL;
273 }
274 
275 
276 static inline int
277 __attribute ((always_inline))
open_dir_stream(int * dfdp,struct ftw_data * data,struct dir_data * dirp)278 open_dir_stream (int *dfdp, struct ftw_data *data, struct dir_data *dirp)
279 {
280   int result = 0;
281 
282   if (data->dirstreams[data->actdir] != NULL)
283     {
284       /* Oh, oh.  We must close this stream.  Get all remaining
285 	 entries and store them as a list in the `content' member of
286 	 the `struct dir_data' variable.  */
287       size_t bufsize = 1024;
288       char *buf = malloc (bufsize);
289 
290       if (buf == NULL)
291 	result = -1;
292       else
293 	{
294 	  DIR *st = data->dirstreams[data->actdir]->stream;
295 	  struct dirent64 *d;
296 	  size_t actsize = 0;
297 
298 	  while ((d = __readdir64 (st)) != NULL)
299 	    {
300 	      size_t this_len = NAMLEN (d);
301 	      if (actsize + this_len + 2 >= bufsize)
302 		{
303 		  char *newp;
304 		  bufsize += MAX (1024, 2 * this_len);
305 		  newp = (char *) realloc (buf, bufsize);
306 		  if (newp == NULL)
307 		    {
308 		      /* No more memory.  */
309 		      int save_err = errno;
310 		      free (buf);
311 		      __set_errno (save_err);
312 		      return -1;
313 		    }
314 		  buf = newp;
315 		}
316 
317 	      *((char *) __mempcpy (buf + actsize, d->d_name, this_len))
318 		= '\0';
319 	      actsize += this_len + 1;
320 	    }
321 
322 	  /* Terminate the list with an additional NUL byte.  */
323 	  buf[actsize++] = '\0';
324 
325 	  /* Shrink the buffer to what we actually need.  */
326 	  void *content = realloc (buf, actsize);
327 	  data->dirstreams[data->actdir]->content = content;
328 	  if (content == NULL)
329 	    {
330 	      int save_err = errno;
331 	      free (buf);
332 	      __set_errno (save_err);
333 	      result = -1;
334 	    }
335 	  else
336 	    {
337 	      __closedir (st);
338 	      data->dirstreams[data->actdir]->stream = NULL;
339 	      data->dirstreams[data->actdir]->streamfd = -1;
340 	      data->dirstreams[data->actdir] = NULL;
341 	    }
342 	}
343     }
344 
345   /* Open the new stream.  */
346   if (result == 0)
347     {
348       assert (data->dirstreams[data->actdir] == NULL);
349 
350       if (dfdp != NULL && *dfdp != -1)
351 	{
352 	  int fd = __openat64_nocancel (*dfdp, data->dirbuf + data->ftw.base,
353 					O_RDONLY | O_DIRECTORY | O_NDELAY);
354 	  dirp->stream = NULL;
355 	  if (fd != -1 && (dirp->stream = __fdopendir (fd)) == NULL)
356 	    __close_nocancel_nostatus (fd);
357 	}
358       else
359 	{
360 	  const char *name;
361 
362 	  if (data->flags & FTW_CHDIR)
363 	    {
364 	      name = data->dirbuf + data->ftw.base;
365 	      if (name[0] == '\0')
366 		name = ".";
367 	    }
368 	  else
369 	    name = data->dirbuf;
370 
371 	  dirp->stream = __opendir (name);
372 	}
373 
374       if (dirp->stream == NULL)
375 	result = -1;
376       else
377 	{
378 	  dirp->streamfd = __dirfd (dirp->stream);
379 	  dirp->content = NULL;
380 	  data->dirstreams[data->actdir] = dirp;
381 
382 	  if (++data->actdir == data->maxdir)
383 	    data->actdir = 0;
384 	}
385     }
386 
387   return result;
388 }
389 
390 
391 static int
process_entry(struct ftw_data * data,struct dir_data * dir,const char * name,size_t namlen,int d_type)392 process_entry (struct ftw_data *data, struct dir_data *dir, const char *name,
393 	       size_t namlen, int d_type)
394 {
395   struct STRUCT_STAT st;
396   int result = 0;
397   int flag = 0;
398   size_t new_buflen;
399 
400   if (name[0] == '.' && (name[1] == '\0'
401 			 || (name[1] == '.' && name[2] == '\0')))
402     /* Don't process the "." and ".." entries.  */
403     return 0;
404 
405   new_buflen = data->ftw.base + namlen + 2;
406   if (data->dirbufsize < new_buflen
407       && !ftw_allocate (data, 2 * new_buflen))
408     return -1;
409 
410   *((char *) __mempcpy (data->dirbuf + data->ftw.base, name, namlen)) = '\0';
411 
412   int statres;
413   if (dir->streamfd != -1)
414     statres = FSTATAT (dir->streamfd, name, &st,
415 		       (data->flags & FTW_PHYS) ? AT_SYMLINK_NOFOLLOW : 0);
416   else
417     {
418       if ((data->flags & FTW_CHDIR) == 0)
419 	name = data->dirbuf;
420 
421       statres = ((data->flags & FTW_PHYS)
422 		 ? LSTAT (name, &st)
423 		 : STAT (name, &st));
424     }
425 
426   if (statres < 0)
427     {
428       if (errno != EACCES && errno != ENOENT)
429 	result = -1;
430       else if (data->flags & FTW_PHYS)
431 	flag = FTW_NS;
432       else
433 	{
434 	  /* Old code left ST undefined for dangling DT_LNK without
435 	     FTW_PHYS set; a clarification at the POSIX level suggests
436 	     it should contain information about the link (ala lstat).
437 	     We do our best to fill in what data we can.  */
438 	  if (dir->streamfd != -1)
439 	    statres = FSTATAT (dir->streamfd, name, &st,
440 			       AT_SYMLINK_NOFOLLOW);
441 	  else
442 	    statres = LSTAT (name, &st);
443 	  if (statres == 0 && S_ISLNK (st.st_mode))
444 	    flag = FTW_SLN;
445 	  else
446 	    flag = FTW_NS;
447 	}
448     }
449   else
450     {
451       if (S_ISDIR (st.st_mode))
452 	flag = FTW_D;
453       else if (S_ISLNK (st.st_mode))
454 	flag = FTW_SL;
455       else
456 	flag = FTW_F;
457     }
458 
459   if (result == 0
460       && (flag == FTW_NS
461 	  || !(data->flags & FTW_MOUNT) || st.st_dev == data->dev))
462     {
463       if (flag == FTW_D)
464 	{
465 	  if ((data->flags & FTW_PHYS)
466 	      || (!find_object (data, &st)
467 		  /* Remember the object.  */
468 		  && (result = add_object (data, &st)) == 0))
469 	    result = ftw_dir (data, &st, dir);
470 	}
471       else
472 	result = (*data->func) (data->dirbuf, &st, data->cvt_arr[flag],
473 				&data->ftw);
474     }
475 
476   if ((data->flags & FTW_ACTIONRETVAL) && result == FTW_SKIP_SUBTREE)
477     result = 0;
478 
479   return result;
480 }
481 
482 
483 static int
484 __attribute ((noinline))
ftw_dir(struct ftw_data * data,struct STRUCT_STAT * st,struct dir_data * old_dir)485 ftw_dir (struct ftw_data *data, struct STRUCT_STAT *st, struct dir_data *old_dir)
486 {
487   struct dir_data dir;
488   struct dirent64 *d;
489   int previous_base = data->ftw.base;
490   int result;
491   char *startp;
492 
493   /* Open the stream for this directory.  This might require that
494      another stream has to be closed.  */
495   result = open_dir_stream (old_dir == NULL ? NULL : &old_dir->streamfd,
496 			    data, &dir);
497   if (result != 0)
498     {
499       if (errno == EACCES)
500 	/* We cannot read the directory.  Signal this with a special flag.  */
501 	result = (*data->func) (data->dirbuf, st, FTW_DNR, &data->ftw);
502 
503       return result;
504     }
505 
506   /* First, report the directory (if not depth-first).  */
507   if (!(data->flags & FTW_DEPTH))
508     {
509       result = (*data->func) (data->dirbuf, st, FTW_D, &data->ftw);
510       if (result != 0)
511 	{
512 	  int save_err;
513 fail:
514 	  save_err = errno;
515 	  __closedir (dir.stream);
516 	  dir.streamfd = -1;
517 	  __set_errno (save_err);
518 
519 	  if (data->actdir-- == 0)
520 	    data->actdir = data->maxdir - 1;
521 	  data->dirstreams[data->actdir] = NULL;
522 	  return result;
523 	}
524     }
525 
526   /* If necessary, change to this directory.  */
527   if (data->flags & FTW_CHDIR)
528     {
529       if (__fchdir (__dirfd (dir.stream)) < 0)
530 	{
531 	  result = -1;
532 	  goto fail;
533 	}
534     }
535 
536   /* Next, update the `struct FTW' information.  */
537   ++data->ftw.level;
538   startp = __rawmemchr (data->dirbuf, '\0');
539   /* There always must be a directory name.  */
540   assert (startp != data->dirbuf);
541   if (startp[-1] != '/')
542     *startp++ = '/';
543   data->ftw.base = startp - data->dirbuf;
544 
545   while (dir.stream != NULL && (d = __readdir64 (dir.stream)) != NULL)
546     {
547       int d_type = DT_UNKNOWN;
548 #ifdef _DIRENT_HAVE_D_TYPE
549       d_type = d->d_type;
550 #endif
551       result = process_entry (data, &dir, d->d_name, NAMLEN (d), d_type);
552       if (result != 0)
553 	break;
554     }
555 
556   if (dir.stream != NULL)
557     {
558       /* The stream is still open.  I.e., we did not need more
559 	 descriptors.  Simply close the stream now.  */
560       int save_err = errno;
561 
562       assert (dir.content == NULL);
563 
564       __closedir (dir.stream);
565       dir.streamfd = -1;
566       __set_errno (save_err);
567 
568       if (data->actdir-- == 0)
569 	data->actdir = data->maxdir - 1;
570       data->dirstreams[data->actdir] = NULL;
571     }
572   else
573     {
574       int save_err;
575       char *runp = dir.content;
576 
577       while (result == 0 && *runp != '\0')
578 	{
579 	  char *endp = strchr (runp, '\0');
580 
581 	  // XXX Should store the d_type values as well?!
582 	  result = process_entry (data, &dir, runp, endp - runp, DT_UNKNOWN);
583 
584 	  runp = endp + 1;
585 	}
586 
587       save_err = errno;
588       free (dir.content);
589       __set_errno (save_err);
590     }
591 
592   if ((data->flags & FTW_ACTIONRETVAL) && result == FTW_SKIP_SIBLINGS)
593     result = 0;
594 
595   /* Prepare the return, revert the `struct FTW' information.  */
596   data->dirbuf[data->ftw.base - 1] = '\0';
597   --data->ftw.level;
598   data->ftw.base = previous_base;
599 
600   /* Finally, if we process depth-first report the directory.  */
601   if (result == 0 && (data->flags & FTW_DEPTH))
602     result = (*data->func) (data->dirbuf, st, FTW_DP, &data->ftw);
603 
604   if (old_dir
605       && (data->flags & FTW_CHDIR)
606       && (result == 0
607 	  || ((data->flags & FTW_ACTIONRETVAL)
608 	      && (result != -1 && result != FTW_STOP))))
609     {
610       /* Change back to the parent directory.  */
611       int done = 0;
612       if (old_dir->stream != NULL)
613 	if (__fchdir (__dirfd (old_dir->stream)) == 0)
614 	  done = 1;
615 
616       if (!done)
617 	{
618 	  if (data->ftw.base == 1)
619 	    {
620 	      if (__chdir ("/") < 0)
621 		result = -1;
622 	    }
623 	  else
624 	    if (__chdir ("..") < 0)
625 	      result = -1;
626 	}
627     }
628 
629   return result;
630 }
631 
632 
633 static int
634 __attribute ((noinline))
ftw_startup(const char * dir,int is_nftw,void * func,int descriptors,int flags)635 ftw_startup (const char *dir, int is_nftw, void *func, int descriptors,
636 	     int flags)
637 {
638   struct ftw_data data = { .dirstreams = NULL };
639   struct STRUCT_STAT st;
640   int result = 0;
641   int save_err;
642   int cwdfd = -1;
643   char *cwd = NULL;
644   char *cp;
645 
646   /* First make sure the parameters are reasonable.  */
647   if (dir[0] == '\0')
648     {
649       __set_errno (ENOENT);
650       return -1;
651     }
652 
653   data.maxdir = descriptors < 1 ? 1 : descriptors;
654   data.actdir = 0;
655   /* PATH_MAX is always defined when we get here.  */
656   if (!ftw_allocate (&data, MAX (2 * strlen (dir), PATH_MAX)))
657     return -1;
658   memset (data.dirstreams, '\0', data.maxdir * sizeof (struct dir_data *));
659   cp = __stpcpy (data.dirbuf, dir);
660   /* Strip trailing slashes.  */
661   while (cp > data.dirbuf + 1 && cp[-1] == '/')
662     --cp;
663   *cp = '\0';
664 
665   data.ftw.level = 0;
666 
667   /* Find basename.  */
668   while (cp > data.dirbuf && cp[-1] != '/')
669     --cp;
670   data.ftw.base = cp - data.dirbuf;
671 
672   data.flags = flags;
673 
674   /* This assignment might seem to be strange but it is what we want.
675      The trick is that the first three arguments to the `ftw' and
676      `nftw' callback functions are equal.  Therefore we can call in
677      every case the callback using the format of the `nftw' version
678      and get the correct result since the stack layout for a function
679      call in C allows this.  */
680   data.func = (NFTW_FUNC_T) func;
681 
682   /* Since we internally use the complete set of FTW_* values we need
683      to reduce the value range before calling a `ftw' callback.  */
684   data.cvt_arr = is_nftw ? nftw_arr : ftw_arr;
685 
686   /* No object known so far.  */
687   data.known_objects = NULL;
688 
689   /* Now go to the directory containing the initial file/directory.  */
690   if (flags & FTW_CHDIR)
691     {
692       /* We have to be able to go back to the current working
693 	 directory.  The best way to do this is to use a file
694 	 descriptor.  */
695       cwdfd = __open (".", O_RDONLY | O_DIRECTORY);
696       if (cwdfd == -1)
697 	{
698 	  /* Try getting the directory name.  This can be needed if
699 	     the current directory is executable but not readable.  */
700 	  if (errno == EACCES)
701 	    /* GNU extension ahead.  */
702 	    cwd =  __getcwd (NULL, 0);
703 
704 	  if (cwd == NULL)
705 	    goto out_fail;
706 	}
707       else if (data.maxdir > 1)
708 	/* Account for the file descriptor we use here.  */
709 	--data.maxdir;
710 
711       if (data.ftw.base > 0)
712 	{
713 	  /* Change to the directory the file is in.  In data.dirbuf
714 	     we have a writable copy of the file name.  Just NUL
715 	     terminate it for now and change the directory.  */
716 	  if (data.ftw.base == 1)
717 	    /* I.e., the file is in the root directory.  */
718 	    result = __chdir ("/");
719 	  else
720 	    {
721 	      char ch = data.dirbuf[data.ftw.base - 1];
722 	      data.dirbuf[data.ftw.base - 1] = '\0';
723 	      result = __chdir (data.dirbuf);
724 	      data.dirbuf[data.ftw.base - 1] = ch;
725 	    }
726 	}
727     }
728 
729   /* Get stat info for start directory.  */
730   if (result == 0)
731     {
732       const char *name;
733 
734       if (data.flags & FTW_CHDIR)
735 	{
736 	  name = data.dirbuf + data.ftw.base;
737 	  if (name[0] == '\0')
738 	    name = ".";
739 	}
740       else
741 	name = data.dirbuf;
742 
743       if (((flags & FTW_PHYS)
744 	   ? LSTAT (name, &st)
745 	   : STAT (name, &st)) < 0)
746 	{
747 	  if (!(flags & FTW_PHYS)
748 	      && errno == ENOENT
749 	      && LSTAT (name, &st) == 0
750 	      && S_ISLNK (st.st_mode))
751 	    result = (*data.func) (data.dirbuf, &st, data.cvt_arr[FTW_SLN],
752 				   &data.ftw);
753 	  else
754 	    /* No need to call the callback since we cannot say anything
755 	       about the object.  */
756 	    result = -1;
757 	}
758       else
759 	{
760 	  if (S_ISDIR (st.st_mode))
761 	    {
762 	      /* Remember the device of the initial directory in case
763 		 FTW_MOUNT is given.  */
764 	      data.dev = st.st_dev;
765 
766 	      /* We know this directory now.  */
767 	      if (!(flags & FTW_PHYS))
768 		result = add_object (&data, &st);
769 
770 	      if (result == 0)
771 		result = ftw_dir (&data, &st, NULL);
772 	    }
773 	  else
774 	    {
775 	      int flag = S_ISLNK (st.st_mode) ? FTW_SL : FTW_F;
776 
777 	      result = (*data.func) (data.dirbuf, &st, data.cvt_arr[flag],
778 				     &data.ftw);
779 	    }
780 	}
781 
782       if ((flags & FTW_ACTIONRETVAL)
783 	  && (result == FTW_SKIP_SUBTREE || result == FTW_SKIP_SIBLINGS))
784 	result = 0;
785     }
786 
787   /* Return to the start directory (if necessary).  */
788   if (cwdfd != -1)
789     {
790       int save_err = errno;
791       __fchdir (cwdfd);
792       __close_nocancel_nostatus (cwdfd);
793       __set_errno (save_err);
794     }
795   else if (cwd != NULL)
796     {
797       int save_err = errno;
798       __chdir (cwd);
799       free (cwd);
800       __set_errno (save_err);
801     }
802 
803   /* Free all memory.  */
804  out_fail:
805   save_err = errno;
806   __tdestroy (data.known_objects, free);
807   free (data.dirstreams);
808   __set_errno (save_err);
809 
810   return result;
811 }
812 
813 
814 
815 /* Entry points.  */
816 
817 int
FTW_NAME(const char * path,FTW_FUNC_T func,int descriptors)818 FTW_NAME (const char *path, FTW_FUNC_T func, int descriptors)
819 {
820   return ftw_startup (path, 0, func, descriptors, 0);
821 }
822 
823 #ifndef NFTW_OLD_NAME
824 int
NFTW_NAME(const char * path,NFTW_FUNC_T func,int descriptors,int flags)825 NFTW_NAME (const char *path, NFTW_FUNC_T func, int descriptors, int flags)
826 {
827   return ftw_startup (path, 1, func, descriptors, flags);
828 }
829 #else
830 
831 # include <shlib-compat.h>
832 
833 int NFTW_NEW_NAME (const char *, NFTW_FUNC_T, int, int);
834 
835 int
NFTW_NEW_NAME(const char * path,NFTW_FUNC_T func,int descriptors,int flags)836 NFTW_NEW_NAME (const char *path, NFTW_FUNC_T func, int descriptors, int flags)
837 {
838   if (flags
839       & ~(FTW_PHYS | FTW_MOUNT | FTW_CHDIR | FTW_DEPTH | FTW_ACTIONRETVAL))
840     {
841       __set_errno (EINVAL);
842       return -1;
843     }
844   return ftw_startup (path, 1, func, descriptors, flags);
845 }
846 versioned_symbol (libc, NFTW_NEW_NAME, NFTW_NAME, GLIBC_2_3_3);
847 
848 # if SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_3_3)
849 
850 /* Older nftw* version just ignored all unknown flags.  */
851 
852 int NFTW_OLD_NAME (const char *, NFTW_FUNC_T, int, int);
853 
854 int
855 attribute_compat_text_section
NFTW_OLD_NAME(const char * path,NFTW_FUNC_T func,int descriptors,int flags)856 NFTW_OLD_NAME (const char *path, NFTW_FUNC_T func, int descriptors, int flags)
857 {
858   flags &= (FTW_PHYS | FTW_MOUNT | FTW_CHDIR | FTW_DEPTH);
859   return ftw_startup (path, 1, func, descriptors, flags);
860 }
861 
862 compat_symbol (libc, NFTW_OLD_NAME, NFTW_NAME, GLIBC_2_1);
863 # endif
864 #endif /* NFTW_OLD_NAME  */
865