1 /* Extract files from a tar archive.
3 Copyright 1988, 1992-1994, 1996-2001, 2003-2007, 2010, 2012-2014 Free
4 Software Foundation, Inc.
6 This file is part of GNU tar.
8 GNU tar is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 GNU tar is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 Written by John Gilmore, on 1985-11-19. */
32 static bool we_are_root
; /* true if our effective uid == 0 */
33 static mode_t newdir_umask
; /* umask when creating new directories */
34 static mode_t current_umask
; /* current umask (which is set to 0 if -p) */
36 #define ALL_MODE_BITS ((mode_t) ~ (mode_t) 0)
38 #if ! HAVE_FCHMOD && ! defined fchmod
39 # define fchmod(fd, mode) (errno = ENOSYS, -1)
41 #if ! HAVE_FCHOWN && ! defined fchown
42 # define fchown(fd, uid, gid) (errno = ENOSYS, -1)
45 /* Return true if an error number ERR means the system call is
46 supported in this case. */
50 return ! (err
== ENOSYS
52 || (EOPNOTSUPP
!= ENOTSUP
&& err
== EOPNOTSUPP
));
55 /* List of directories whose statuses we need to extract after we've
56 finished extracting their subsidiary files. If you consider each
57 contiguous subsequence of elements of the form [D]?[^D]*, where [D]
58 represents an element where AFTER_LINKS is nonzero and [^D]
59 represents an element where AFTER_LINKS is zero, then the head
60 of the subsequence has the longest name, and each non-head element
61 in the prefix is an ancestor (in the directory hierarchy) of the
64 struct delayed_set_stat
66 /* Next directory in list. */
67 struct delayed_set_stat
*next
;
69 /* Metadata for this directory. */
72 mode_t mode
; /* The desired mode is MODE & ~ current_umask. */
75 struct timespec atime
;
76 struct timespec mtime
;
78 /* An estimate of the directory's current mode, along with a mask
79 specifying which bits of this estimate are known to be correct.
80 If CURRENT_MODE_MASK is zero, CURRENT_MODE's value doesn't
83 mode_t current_mode_mask
;
85 /* This directory is an intermediate directory that was created
86 as an ancestor of some other directory; it was not mentioned
87 in the archive, so do not set its uid, gid, atime, or mtime,
88 and don't alter its mode outside of MODE_RWX. */
91 /* Whether symbolic links should be followed when accessing the
95 /* Do not set the status of this directory until after delayed
99 /* Directory that the name is relative to. */
102 /* extended attributes*/
108 size_t xattr_map_size
;
109 struct xattr_array
*xattr_map
;
110 /* Length and contents of name. */
111 size_t file_name_len
;
115 static struct delayed_set_stat
*delayed_set_stat_head
;
117 /* List of links whose creation we have delayed. */
120 /* The next delayed link in the list. */
121 struct delayed_link
*next
;
123 /* The device, inode number and birthtime of the placeholder.
124 birthtime.tv_nsec is negative if the birthtime is not available.
125 Don't use mtime as this would allow for false matches if some
126 other process removes the placeholder. Don't use ctime as
127 this would cause race conditions and other screwups, e.g.,
128 when restoring hard-linked symlinks. */
131 struct timespec birthtime
;
133 /* True if the link is symbolic. */
136 /* The desired metadata, valid only the link is symbolic. */
140 struct timespec atime
;
141 struct timespec mtime
;
143 /* The directory that the sources and target are relative to. */
146 /* A list of sources for this link. The sources are all to be
147 hard-linked together. */
148 struct string_list
*sources
;
150 /* SELinux context */
159 size_t xattr_map_size
;
160 struct xattr_array
*xattr_map
;
162 /* The desired target of the desired link. */
166 static struct delayed_link
*delayed_link_head
;
170 struct string_list
*next
;
174 /* Set up to extract files. */
178 we_are_root
= geteuid () == ROOT_UID
;
179 same_permissions_option
+= we_are_root
;
180 same_owner_option
+= we_are_root
;
182 /* Option -p clears the kernel umask, so it does not affect proper
183 restoration of file permissions. New intermediate directories will
184 comply with umask at start of program. */
186 newdir_umask
= umask (0);
187 if (0 < same_permissions_option
)
191 umask (newdir_umask
); /* restore the kernel umask */
192 current_umask
= newdir_umask
;
196 /* Use fchmod if possible, fchmodat otherwise. */
198 fd_chmod (int fd
, char const *file
, mode_t mode
, int atflag
)
202 int result
= fchmod (fd
, mode
);
203 if (result
== 0 || implemented (errno
))
206 return fchmodat (chdir_fd
, file
, mode
, atflag
);
209 /* Use fchown if possible, fchownat otherwise. */
211 fd_chown (int fd
, char const *file
, uid_t uid
, gid_t gid
, int atflag
)
215 int result
= fchown (fd
, uid
, gid
);
216 if (result
== 0 || implemented (errno
))
219 return fchownat (chdir_fd
, file
, uid
, gid
, atflag
);
222 /* Use fstat if possible, fstatat otherwise. */
224 fd_stat (int fd
, char const *file
, struct stat
*st
, int atflag
)
228 : fstatat (chdir_fd
, file
, st
, atflag
));
231 /* Set the mode for FILE_NAME to MODE.
232 MODE_MASK specifies the bits of MODE that we care about;
233 thus if MODE_MASK is zero, do nothing.
234 If FD is nonnegative, it is a file descriptor for the file.
235 CURRENT_MODE and CURRENT_MODE_MASK specify information known about
236 the file's current mode, using the style of struct delayed_set_stat.
237 TYPEFLAG specifies the type of the file.
238 ATFLAG specifies the flag to use when statting the file. */
240 set_mode (char const *file_name
,
241 mode_t mode
, mode_t mode_mask
, int fd
,
242 mode_t current_mode
, mode_t current_mode_mask
,
243 char typeflag
, int atflag
)
245 if (((current_mode
^ mode
) | ~ current_mode_mask
) & mode_mask
)
247 if (MODE_ALL
& ~ mode_mask
& ~ current_mode_mask
)
250 if (fd_stat (fd
, file_name
, &st
, atflag
) != 0)
252 stat_error (file_name
);
255 current_mode
= st
.st_mode
;
258 current_mode
&= MODE_ALL
;
259 mode
= (current_mode
& ~ mode_mask
) | (mode
& mode_mask
);
261 if (current_mode
!= mode
)
264 fd_chmod (fd
, file_name
, mode
, atflag
) == 0 ? 0 : errno
;
266 /* On Solaris, chmod may fail if we don't have PRIV_ALL, because
267 setuid-root files would otherwise be a backdoor. See
268 http://opensolaris.org/jive/thread.jspa?threadID=95826
270 if (chmod_errno
== EPERM
&& (mode
& S_ISUID
)
271 && priv_set_restore_linkdir () == 0)
274 fd_chmod (fd
, file_name
, mode
, atflag
) == 0 ? 0 : errno
;
275 priv_set_remove_linkdir ();
278 /* Linux fchmodat does not support AT_SYMLINK_NOFOLLOW, and
279 returns ENOTSUP even when operating on non-symlinks, try
280 again with the flag disabled if it does not appear to be
281 supported and if the file is not a symlink. This
282 introduces a race, alas. */
283 if (atflag
&& typeflag
!= SYMTYPE
&& ! implemented (chmod_errno
))
284 chmod_errno
= fd_chmod (fd
, file_name
, mode
, 0) == 0 ? 0 : errno
;
287 && (typeflag
!= SYMTYPE
|| implemented (chmod_errno
)))
290 chmod_error_details (file_name
, mode
);
296 /* Check time after successfully setting FILE_NAME's time stamp to T. */
298 check_time (char const *file_name
, struct timespec t
)
301 WARNOPT (WARN_TIMESTAMP
,
302 (0, 0, _("%s: implausibly old time stamp %s"),
303 file_name
, tartime (t
, true)));
304 else if (timespec_cmp (volume_start_time
, t
) < 0)
308 if (timespec_cmp (now
, t
) < 0)
310 char buf
[TIMESPEC_STRSIZE_BOUND
];
311 struct timespec diff
;
312 diff
.tv_sec
= t
.tv_sec
- now
.tv_sec
;
313 diff
.tv_nsec
= t
.tv_nsec
- now
.tv_nsec
;
314 if (diff
.tv_nsec
< 0)
316 diff
.tv_nsec
+= BILLION
;
319 WARNOPT (WARN_TIMESTAMP
,
320 (0, 0, _("%s: time stamp %s is %s s in the future"),
321 file_name
, tartime (t
, true), code_timespec (diff
, buf
)));
326 /* Restore stat attributes (owner, group, mode and times) for
327 FILE_NAME, using information given in *ST.
328 If FD is nonnegative, it is a file descriptor for the file.
329 CURRENT_MODE and CURRENT_MODE_MASK specify information known about
330 the file's current mode, using the style of struct delayed_set_stat.
331 TYPEFLAG specifies the type of the file.
332 If INTERDIR, this is an intermediate directory.
333 ATFLAG specifies the flag to use when statting the file. */
336 set_stat (char const *file_name
,
337 struct tar_stat_info
const *st
,
338 int fd
, mode_t current_mode
, mode_t current_mode_mask
,
339 char typeflag
, bool interdir
, int atflag
)
341 /* Do the utime before the chmod because some versions of utime are
342 broken and trash the modes of the file. */
344 if (! touch_option
&& ! interdir
)
346 struct timespec ts
[2];
347 if (incremental_option
)
350 ts
[0].tv_nsec
= UTIME_OMIT
;
353 if (fdutimensat (fd
, chdir_fd
, file_name
, ts
, atflag
) == 0)
355 if (incremental_option
)
356 check_time (file_name
, ts
[0]);
357 check_time (file_name
, ts
[1]);
359 else if (typeflag
!= SYMTYPE
|| implemented (errno
))
360 utime_error (file_name
);
363 if (0 < same_owner_option
&& ! interdir
)
365 /* Some systems allow non-root users to give files away. Once this
366 done, it is not possible anymore to change file permissions.
367 However, setting file permissions now would be incorrect, since
368 they would apply to the wrong user, and there would be a race
369 condition. So, don't use systems that allow non-root users to
371 uid_t uid
= st
->stat
.st_uid
;
372 gid_t gid
= st
->stat
.st_gid
;
374 if (fd_chown (fd
, file_name
, uid
, gid
, atflag
) == 0)
376 /* Changing the owner can clear st_mode bits in some cases. */
377 if ((current_mode
| ~ current_mode_mask
) & S_IXUGO
)
378 current_mode_mask
&= ~ (current_mode
& (S_ISUID
| S_ISGID
));
380 else if (typeflag
!= SYMTYPE
|| implemented (errno
))
381 chown_error_details (file_name
, uid
, gid
);
385 st
->stat
.st_mode
& ~ current_umask
,
386 0 < same_permissions_option
&& ! interdir
? MODE_ALL
: MODE_RWX
,
387 fd
, current_mode
, current_mode_mask
, typeflag
, atflag
);
389 /* these three calls must be done *after* fd_chown() call because fd_chown
390 causes that linux capabilities becomes cleared. */
391 xattrs_xattrs_set (st
, file_name
, typeflag
, 1);
392 xattrs_acls_set (st
, file_name
, typeflag
);
393 xattrs_selinux_set (st
, file_name
, typeflag
);
396 /* For each entry H in the leading prefix of entries in HEAD that do
397 not have after_links marked, mark H and fill in its dev and ino
398 members. Assume HEAD && ! HEAD->after_links. */
400 mark_after_links (struct delayed_set_stat
*head
)
402 struct delayed_set_stat
*h
= head
;
409 if (deref_stat (h
->file_name
, &st
) != 0)
410 stat_error (h
->file_name
);
417 while ((h
= h
->next
) && ! h
->after_links
);
420 /* Remember to restore stat attributes (owner, group, mode and times)
421 for the directory FILE_NAME, using information given in *ST,
422 once we stop extracting files into that directory.
424 If ST is null, merely create a placeholder node for an intermediate
425 directory that was created by make_directories.
427 NOTICE: this works only if the archive has usual member order, i.e.
428 directory, then the files in that directory. Incremental archive have
429 somewhat reversed order: first go subdirectories, then all other
430 members. To help cope with this case the variable
431 delay_directory_restore_option is set by prepare_to_extract.
433 If an archive was explicitely created so that its member order is
434 reversed, some directory timestamps can be restored incorrectly,
436 tar --no-recursion -cf archive dir dir/file1 foo dir/file2
439 delay_set_stat (char const *file_name
, struct tar_stat_info
const *st
,
440 mode_t current_mode
, mode_t current_mode_mask
,
441 mode_t mode
, int atflag
)
443 size_t file_name_len
= strlen (file_name
);
444 struct delayed_set_stat
*data
=
445 xmalloc (offsetof (struct delayed_set_stat
, file_name
)
446 + file_name_len
+ 1);
447 data
->next
= delayed_set_stat_head
;
451 data
->dev
= st
->stat
.st_dev
;
452 data
->ino
= st
->stat
.st_ino
;
453 data
->uid
= st
->stat
.st_uid
;
454 data
->gid
= st
->stat
.st_gid
;
455 data
->atime
= st
->atime
;
456 data
->mtime
= st
->mtime
;
458 data
->file_name_len
= file_name_len
;
459 data
->current_mode
= current_mode
;
460 data
->current_mode_mask
= current_mode_mask
;
461 data
->interdir
= ! st
;
462 data
->atflag
= atflag
;
463 data
->after_links
= 0;
464 data
->change_dir
= chdir_current
;
465 data
->cntx_name
= NULL
;
467 assign_string (&data
->cntx_name
, st
->cntx_name
);
468 if (st
&& st
->acls_a_ptr
)
470 data
->acls_a_ptr
= xmemdup (st
->acls_a_ptr
, st
->acls_a_len
+ 1);
471 data
->acls_a_len
= st
->acls_a_len
;
475 data
->acls_a_ptr
= NULL
;
476 data
->acls_a_len
= 0;
478 if (st
&& st
->acls_d_ptr
)
480 data
->acls_d_ptr
= xmemdup (st
->acls_d_ptr
, st
->acls_d_len
+ 1);
481 data
->acls_d_len
= st
->acls_d_len
;
485 data
->acls_d_ptr
= NULL
;
486 data
->acls_d_len
= 0;
489 xheader_xattr_copy (st
, &data
->xattr_map
, &data
->xattr_map_size
);
492 data
->xattr_map
= NULL
;
493 data
->xattr_map_size
= 0;
495 strcpy (data
->file_name
, file_name
);
496 delayed_set_stat_head
= data
;
497 if (must_be_dot_or_slash (file_name
))
498 mark_after_links (data
);
501 /* Update the delayed_set_stat info for an intermediate directory
502 created within the file name of DIR. The intermediate directory turned
503 out to be the same as this directory, e.g. due to ".." or symbolic
504 links. *DIR_STAT_INFO is the status of the directory. */
506 repair_delayed_set_stat (char const *dir
,
507 struct stat
const *dir_stat_info
)
509 struct delayed_set_stat
*data
;
510 for (data
= delayed_set_stat_head
; data
; data
= data
->next
)
513 if (fstatat (chdir_fd
, data
->file_name
, &st
, data
->atflag
) != 0)
515 stat_error (data
->file_name
);
519 if (st
.st_dev
== dir_stat_info
->st_dev
520 && st
.st_ino
== dir_stat_info
->st_ino
)
522 data
->dev
= current_stat_info
.stat
.st_dev
;
523 data
->ino
= current_stat_info
.stat
.st_ino
;
524 data
->mode
= current_stat_info
.stat
.st_mode
;
525 data
->uid
= current_stat_info
.stat
.st_uid
;
526 data
->gid
= current_stat_info
.stat
.st_gid
;
527 data
->atime
= current_stat_info
.atime
;
528 data
->mtime
= current_stat_info
.mtime
;
529 data
->current_mode
= st
.st_mode
;
530 data
->current_mode_mask
= ALL_MODE_BITS
;
531 data
->interdir
= false;
536 ERROR ((0, 0, _("%s: Unexpected inconsistency when making directory"),
537 quotearg_colon (dir
)));
541 free_delayed_set_stat (struct delayed_set_stat
*data
)
543 xheader_xattr_free (data
->xattr_map
, data
->xattr_map_size
);
544 free (data
->cntx_name
);
545 free (data
->acls_a_ptr
);
546 free (data
->acls_d_ptr
);
551 remove_delayed_set_stat (const char *fname
)
553 struct delayed_set_stat
*data
, *next
, *prev
= NULL
;
554 for (data
= delayed_set_stat_head
; data
; data
= next
)
557 if (chdir_current
== data
->change_dir
558 && strcmp (data
->file_name
, fname
) == 0)
560 free_delayed_set_stat (data
);
564 delayed_set_stat_head
= next
;
572 /* After a file/link/directory creation has failed, see if
573 it's because some required directory was not present, and if so,
574 create all required directories. Return zero if all the required
575 directories were created, nonzero (issuing a diagnostic) otherwise.
576 Set *INTERDIR_MADE if at least one directory was created. */
578 make_directories (char *file_name
, bool *interdir_made
)
580 char *cursor0
= file_name
+ FILE_SYSTEM_PREFIX_LEN (file_name
);
581 char *cursor
; /* points into the file name */
583 for (cursor
= cursor0
; *cursor
; cursor
++)
589 if (! ISSLASH (*cursor
))
592 /* Avoid mkdir of empty string, if leading or double '/'. */
594 if (cursor
== cursor0
|| ISSLASH (cursor
[-1]))
597 /* Avoid mkdir where last part of file name is "." or "..". */
599 if (cursor
[-1] == '.'
600 && (cursor
== cursor0
+ 1 || ISSLASH (cursor
[-2])
601 || (cursor
[-2] == '.'
602 && (cursor
== cursor0
+ 2 || ISSLASH (cursor
[-3])))))
605 *cursor
= '\0'; /* truncate the name there */
606 desired_mode
= MODE_RWX
& ~ newdir_umask
;
607 mode
= desired_mode
| (we_are_root
? 0 : MODE_WXUSR
);
608 status
= mkdirat (chdir_fd
, file_name
, mode
);
612 /* Create a struct delayed_set_stat even if
613 mode == desired_mode, because
614 repair_delayed_set_stat may need to update the struct. */
615 delay_set_stat (file_name
,
616 0, mode
& ~ current_umask
, MODE_RWX
,
617 desired_mode
, AT_SYMLINK_NOFOLLOW
);
619 print_for_mkdir (file_name
, cursor
- file_name
, desired_mode
);
620 *interdir_made
= true;
622 else if (errno
== EEXIST
)
626 /* Check whether the desired file exists. Even when the
627 file exists, mkdir can fail with some errno value E other
628 than EEXIST, so long as E describes an error condition
629 that also applies. */
632 status
= fstatat (chdir_fd
, file_name
, &st
, 0);
636 mkdir_error (file_name
);
648 /* Return true if FILE_NAME (with status *STP, if STP) is not a
649 directory, and has a time stamp newer than (or equal to) that of
652 file_newer_p (const char *file_name
, struct stat
const *stp
,
653 struct tar_stat_info
*tar_stat
)
659 if (deref_stat (file_name
, &st
) != 0)
663 stat_warn (file_name
);
664 /* Be safer: if the file exists, assume it is newer. */
672 return (! S_ISDIR (stp
->st_mode
)
673 && tar_timespec_cmp (tar_stat
->mtime
, get_stat_mtime (stp
)) <= 0);
678 #define RECOVER_SKIP 2
680 /* Attempt repairing what went wrong with the extraction. Delete an
681 already existing file or create missing intermediate directories.
682 Return RECOVER_OK if we somewhat increased our chances at a successful
683 extraction, RECOVER_NO if there are no chances, and RECOVER_SKIP if the
684 caller should skip extraction of that member. The value of errno is
685 properly restored on returning RECOVER_NO.
687 If REGULAR, the caller was trying to extract onto a regular file.
689 Set *INTERDIR_MADE if an intermediate directory is made as part of
690 the recovery process. */
693 maybe_recoverable (char *file_name
, bool regular
, bool *interdir_made
)
697 struct stat
const *stp
= 0;
706 /* With open ("symlink", O_NOFOLLOW|...), POSIX says errno == ELOOP,
707 but some operating systems do not conform to the standard. */
709 /* NetBSD uses errno == EFTYPE; see <http://gnats.netbsd.org/43154>. */
712 /* FreeBSD 8.1 uses errno == EMLINK. */
714 /* Tru64 5.1B uses errno == ENOTSUP. */
718 || old_files_option
!= OVERWRITE_OLD_FILES
|| dereference_option
)
720 if (strchr (file_name
, '/'))
722 if (deref_stat (file_name
, &st
) != 0)
727 /* The caller tried to open a symbolic link with O_NOFOLLOW.
728 Fall through, treating it as an already-existing file. */
731 /* Remove an old file, if the options allow this. */
733 switch (old_files_option
)
736 WARNOPT (WARN_EXISTING_FILE
,
737 (0, 0, _("%s: skipping existing file"), file_name
));
743 case KEEP_NEWER_FILES
:
744 if (file_newer_p (file_name
, stp
, ¤t_stat_info
))
748 case DEFAULT_OLD_FILES
:
749 case NO_OVERWRITE_DIR_OLD_FILES
:
750 case OVERWRITE_OLD_FILES
:
751 if (0 < remove_any_file (file_name
, ORDINARY_REMOVE_OPTION
))
755 case UNLINK_FIRST_OLD_FILES
:
760 /* Attempt creating missing intermediate directories. */
761 if (make_directories (file_name
, interdir_made
) == 0 && *interdir_made
)
766 /* Just say we can't do anything about it... */
774 /* Restore stat extended attributes (xattr) for FILE_NAME, using information
775 given in *ST. Restore before extraction because they may affect file layout
776 (e.g. on Lustre distributed parallel filesystem - setting info about how many
777 servers is this file striped over, stripe size, mirror copies, etc.
778 in advance dramatically improves the following performance of reading and
779 writing a file). If not restoring permissions, invert the INVERT_PERMISSIONS
780 bits from the file's current permissions. TYPEFLAG specifies the type of the
781 file. FILE_CREATED indicates set_xattr has created the file */
783 set_xattr (char const *file_name
, struct tar_stat_info
const *st
,
784 mode_t invert_permissions
, char typeflag
, int *file_created
)
789 bool interdir_made
= false;
791 if ((xattrs_option
> 0) && st
->xattr_map_size
)
793 mode_t mode
= current_stat_info
.stat
.st_mode
& MODE_RWX
& ~ current_umask
;
796 status
= mknodat (chdir_fd
, file_name
, mode
^ invert_permissions
, 0);
797 while (status
&& maybe_recoverable ((char *)file_name
, false,
800 xattrs_xattrs_set (st
, file_name
, typeflag
, 0);
808 /* Fix the statuses of all directories whose statuses need fixing, and
809 which are not ancestors of FILE_NAME. If AFTER_LINKS is
810 nonzero, do this for all such directories; otherwise, stop at the
811 first directory that is marked to be fixed up only after delayed
812 links are applied. */
814 apply_nonancestor_delayed_set_stat (char const *file_name
, bool after_links
)
816 size_t file_name_len
= strlen (file_name
);
817 bool check_for_renamed_directories
= 0;
819 while (delayed_set_stat_head
)
821 struct delayed_set_stat
*data
= delayed_set_stat_head
;
822 bool skip_this_one
= 0;
824 mode_t current_mode
= data
->current_mode
;
825 mode_t current_mode_mask
= data
->current_mode_mask
;
827 check_for_renamed_directories
|= data
->after_links
;
829 if (after_links
< data
->after_links
830 || (data
->file_name_len
< file_name_len
831 && file_name
[data
->file_name_len
]
832 && (ISSLASH (file_name
[data
->file_name_len
])
833 || ISSLASH (file_name
[data
->file_name_len
- 1]))
834 && memcmp (file_name
, data
->file_name
, data
->file_name_len
) == 0))
837 chdir_do (data
->change_dir
);
839 if (check_for_renamed_directories
)
841 if (fstatat (chdir_fd
, data
->file_name
, &st
, data
->atflag
) != 0)
843 stat_error (data
->file_name
);
848 current_mode
= st
.st_mode
;
849 current_mode_mask
= ALL_MODE_BITS
;
850 if (! (st
.st_dev
== data
->dev
&& st
.st_ino
== data
->ino
))
853 _("%s: Directory renamed before its status could be extracted"),
854 quotearg_colon (data
->file_name
)));
862 struct tar_stat_info sb
;
863 sb
.stat
.st_mode
= data
->mode
;
864 sb
.stat
.st_uid
= data
->uid
;
865 sb
.stat
.st_gid
= data
->gid
;
866 sb
.atime
= data
->atime
;
867 sb
.mtime
= data
->mtime
;
868 sb
.cntx_name
= data
->cntx_name
;
869 sb
.acls_a_ptr
= data
->acls_a_ptr
;
870 sb
.acls_a_len
= data
->acls_a_len
;
871 sb
.acls_d_ptr
= data
->acls_d_ptr
;
872 sb
.acls_d_len
= data
->acls_d_len
;
873 sb
.xattr_map
= data
->xattr_map
;
874 sb
.xattr_map_size
= data
->xattr_map_size
;
875 set_stat (data
->file_name
, &sb
,
876 -1, current_mode
, current_mode_mask
,
877 DIRTYPE
, data
->interdir
, data
->atflag
);
880 delayed_set_stat_head
= data
->next
;
881 free_delayed_set_stat (data
);
887 is_directory_link (const char *file_name
)
893 res
= (fstatat (chdir_fd
, file_name
, &st
, AT_SYMLINK_NOFOLLOW
) == 0 &&
894 S_ISLNK (st
.st_mode
) &&
895 fstatat (chdir_fd
, file_name
, &st
, 0) == 0 &&
896 S_ISDIR (st
.st_mode
));
901 /* Extractor functions for various member types */
904 extract_dir (char *file_name
, int typeflag
)
908 mode_t current_mode
= 0;
909 mode_t current_mode_mask
= 0;
911 bool interdir_made
= false;
913 /* Save 'root device' to avoid purging mount points. */
914 if (one_file_system_option
&& root_device
== 0)
918 if (fstatat (chdir_fd
, ".", &st
, 0) != 0)
921 root_device
= st
.st_dev
;
924 if (incremental_option
)
925 /* Read the entry and delete files that aren't listed in the archive. */
926 purge_directory (file_name
);
927 else if (typeflag
== GNUTYPE_DUMPDIR
)
930 /* If ownership or permissions will be restored later, create the
931 directory with restrictive permissions at first, so that in the
932 meantime processes owned by other users do not inadvertently
933 create files under this directory that inherit the wrong owner,
934 group, or permissions from the directory. If not root, though,
935 make the directory writeable and searchable at first, so that
936 files can be created under it. */
937 mode
= ((current_stat_info
.stat
.st_mode
938 & (0 < same_owner_option
|| 0 < same_permissions_option
941 | (we_are_root
? 0 : MODE_WXUSR
));
945 status
= mkdirat (chdir_fd
, file_name
, mode
);
948 current_mode
= mode
& ~ current_umask
;
949 current_mode_mask
= MODE_RWX
;
950 atflag
= AT_SYMLINK_NOFOLLOW
;
956 || keep_directory_symlink_option
957 || old_files_option
== DEFAULT_OLD_FILES
958 || old_files_option
== OVERWRITE_OLD_FILES
))
962 if (keep_directory_symlink_option
&& is_directory_link (file_name
))
965 if (deref_stat (file_name
, &st
) == 0)
967 current_mode
= st
.st_mode
;
968 current_mode_mask
= ALL_MODE_BITS
;
970 if (S_ISDIR (current_mode
))
974 repair_delayed_set_stat (file_name
, &st
);
983 switch (maybe_recoverable (file_name
, false, &interdir_made
))
994 mkdir_error (file_name
);
1003 || old_files_option
== DEFAULT_OLD_FILES
1004 || old_files_option
== OVERWRITE_OLD_FILES
)
1005 delay_set_stat (file_name
, ¤t_stat_info
,
1006 current_mode
, current_mode_mask
,
1007 current_stat_info
.stat
.st_mode
, atflag
);
1014 open_output_file (char const *file_name
, int typeflag
, mode_t mode
,
1015 int file_created
, mode_t
*current_mode
,
1016 mode_t
*current_mode_mask
)
1019 bool overwriting_old_files
= old_files_option
== OVERWRITE_OLD_FILES
;
1020 int openflag
= (O_WRONLY
| O_BINARY
| O_CLOEXEC
| O_NOCTTY
| O_NONBLOCK
1022 | (overwriting_old_files
1023 ? O_TRUNC
| (dereference_option
? 0 : O_NOFOLLOW
)
1026 /* File might be created in set_xattr. So clear O_EXCL to avoid open() fail */
1028 openflag
= openflag
& ~O_EXCL
;
1030 if (typeflag
== CONTTYPE
)
1032 static int conttype_diagnosed
;
1034 if (!conttype_diagnosed
)
1036 conttype_diagnosed
= 1;
1037 WARNOPT (WARN_CONTIGUOUS_CAST
,
1038 (0, 0, _("Extracting contiguous files as regular files")));
1042 /* If O_NOFOLLOW is needed but does not work, check for a symlink
1043 separately. There's a race condition, but that cannot be avoided
1044 on hosts lacking O_NOFOLLOW. */
1045 if (! HAVE_WORKING_O_NOFOLLOW
1046 && overwriting_old_files
&& ! dereference_option
)
1049 if (fstatat (chdir_fd
, file_name
, &st
, AT_SYMLINK_NOFOLLOW
) == 0
1050 && S_ISLNK (st
.st_mode
))
1057 fd
= openat (chdir_fd
, file_name
, openflag
, mode
);
1060 if (overwriting_old_files
)
1063 if (fstat (fd
, &st
) != 0)
1070 if (! S_ISREG (st
.st_mode
))
1076 *current_mode
= st
.st_mode
;
1077 *current_mode_mask
= ALL_MODE_BITS
;
1081 *current_mode
= mode
& ~ current_umask
;
1082 *current_mode_mask
= MODE_RWX
;
1090 extract_file (char *file_name
, int typeflag
)
1094 union block
*data_block
;
1098 bool interdir_made
= false;
1099 mode_t mode
= (current_stat_info
.stat
.st_mode
& MODE_RWX
1100 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
1101 mode_t invert_permissions
= 0 < same_owner_option
? mode
& (S_IRWXG
| S_IRWXO
)
1103 mode_t current_mode
= 0;
1104 mode_t current_mode_mask
= 0;
1106 if (to_stdout_option
)
1108 else if (to_command_option
)
1110 fd
= sys_exec_command (file_name
, 'f', ¤t_stat_info
);
1119 int file_created
= 0;
1120 if (set_xattr (file_name
, ¤t_stat_info
, invert_permissions
,
1121 typeflag
, &file_created
))
1124 open_error (file_name
);
1128 while ((fd
= open_output_file (file_name
, typeflag
, mode
,
1129 file_created
, ¤t_mode
,
1130 ¤t_mode_mask
))
1133 int recover
= maybe_recoverable (file_name
, true, &interdir_made
);
1134 if (recover
!= RECOVER_OK
)
1137 if (recover
== RECOVER_SKIP
)
1139 open_error (file_name
);
1145 mv_begin_read (¤t_stat_info
);
1146 if (current_stat_info
.is_sparse
)
1147 sparse_extract_file (fd
, ¤t_stat_info
, &size
);
1149 for (size
= current_stat_info
.stat
.st_size
; size
> 0; )
1151 mv_size_left (size
);
1153 /* Locate data, determine max length writeable, write it,
1154 block that we have used the data, then check if the write
1157 data_block
= find_next_block ();
1160 ERROR ((0, 0, _("Unexpected EOF in archive")));
1161 break; /* FIXME: What happens, then? */
1164 written
= available_space_after (data_block
);
1169 count
= blocking_write (fd
, data_block
->buffer
, written
);
1172 set_next_block_after ((union block
*)
1173 (data_block
->buffer
+ written
- 1));
1174 if (count
!= written
)
1176 if (!to_command_option
)
1177 write_error_details (file_name
, count
, written
);
1178 /* FIXME: shouldn't we restore from backup? */
1187 /* If writing to stdout, don't try to do anything to the filename;
1188 it doesn't exist, or we don't want to touch it anyway. */
1190 if (to_stdout_option
)
1193 if (! to_command_option
)
1194 set_stat (file_name
, ¤t_stat_info
, fd
,
1195 current_mode
, current_mode_mask
, typeflag
, false,
1196 (old_files_option
== OVERWRITE_OLD_FILES
1197 ? 0 : AT_SYMLINK_NOFOLLOW
));
1199 status
= close (fd
);
1201 close_error (file_name
);
1203 if (to_command_option
)
1204 sys_wait_command ();
1209 /* Create a placeholder file with name FILE_NAME, which will be
1210 replaced after other extraction is done by a symbolic link if
1211 IS_SYMLINK is true, and by a hard link otherwise. Set
1212 *INTERDIR_MADE if an intermediate directory is made in the
1216 create_placeholder_file (char *file_name
, bool is_symlink
, bool *interdir_made
)
1221 while ((fd
= openat (chdir_fd
, file_name
, O_WRONLY
| O_CREAT
| O_EXCL
, 0)) < 0)
1223 switch (maybe_recoverable (file_name
, false, interdir_made
))
1232 open_error (file_name
);
1237 if (fstat (fd
, &st
) != 0)
1239 stat_error (file_name
);
1242 else if (close (fd
) != 0)
1243 close_error (file_name
);
1246 struct delayed_set_stat
*h
;
1247 struct delayed_link
*p
=
1248 xmalloc (offsetof (struct delayed_link
, target
)
1249 + strlen (current_stat_info
.link_name
)
1251 p
->next
= delayed_link_head
;
1252 delayed_link_head
= p
;
1255 p
->birthtime
= get_stat_birthtime (&st
);
1256 p
->is_symlink
= is_symlink
;
1259 p
->mode
= current_stat_info
.stat
.st_mode
;
1260 p
->uid
= current_stat_info
.stat
.st_uid
;
1261 p
->gid
= current_stat_info
.stat
.st_gid
;
1262 p
->atime
= current_stat_info
.atime
;
1263 p
->mtime
= current_stat_info
.mtime
;
1265 p
->change_dir
= chdir_current
;
1266 p
->sources
= xmalloc (offsetof (struct string_list
, string
)
1267 + strlen (file_name
) + 1);
1268 p
->sources
->next
= 0;
1269 strcpy (p
->sources
->string
, file_name
);
1270 p
->cntx_name
= NULL
;
1271 assign_string (&p
->cntx_name
, current_stat_info
.cntx_name
);
1272 p
->acls_a_ptr
= NULL
;
1274 p
->acls_d_ptr
= NULL
;
1276 xheader_xattr_copy (¤t_stat_info
, &p
->xattr_map
, &p
->xattr_map_size
);
1277 strcpy (p
->target
, current_stat_info
.link_name
);
1279 h
= delayed_set_stat_head
;
1280 if (h
&& ! h
->after_links
1281 && strncmp (file_name
, h
->file_name
, h
->file_name_len
) == 0
1282 && ISSLASH (file_name
[h
->file_name_len
])
1283 && (last_component (file_name
) == file_name
+ h
->file_name_len
+ 1))
1284 mark_after_links (h
);
1293 extract_link (char *file_name
, int typeflag
)
1295 bool interdir_made
= false;
1296 char const *link_name
;
1299 link_name
= current_stat_info
.link_name
;
1301 if (! absolute_names_option
&& contains_dot_dot (link_name
))
1302 return create_placeholder_file (file_name
, false, &interdir_made
);
1306 struct stat st1
, st2
;
1308 int status
= linkat (chdir_fd
, link_name
, chdir_fd
, file_name
, 0);
1313 struct delayed_link
*ds
= delayed_link_head
;
1315 && fstatat (chdir_fd
, link_name
, &st1
, AT_SYMLINK_NOFOLLOW
) == 0)
1316 for (; ds
; ds
= ds
->next
)
1317 if (ds
->change_dir
== chdir_current
1318 && ds
->dev
== st1
.st_dev
1319 && ds
->ino
== st1
.st_ino
1320 && (timespec_cmp (ds
->birthtime
, get_stat_birthtime (&st1
))
1323 struct string_list
*p
= xmalloc (offsetof (struct string_list
, string
)
1324 + strlen (file_name
) + 1);
1325 strcpy (p
->string
, file_name
);
1326 p
->next
= ds
->sources
;
1332 else if ((e
== EEXIST
&& strcmp (link_name
, file_name
) == 0)
1333 || ((fstatat (chdir_fd
, link_name
, &st1
, AT_SYMLINK_NOFOLLOW
)
1335 && (fstatat (chdir_fd
, file_name
, &st2
, AT_SYMLINK_NOFOLLOW
)
1337 && st1
.st_dev
== st2
.st_dev
1338 && st1
.st_ino
== st2
.st_ino
))
1343 while ((rc
= maybe_recoverable (file_name
, false, &interdir_made
))
1346 if (rc
== RECOVER_SKIP
)
1348 if (!(incremental_option
&& errno
== EEXIST
))
1350 link_error (link_name
, file_name
);
1357 extract_symlink (char *file_name
, int typeflag
)
1360 bool interdir_made
= false;
1362 if (! absolute_names_option
1363 && (IS_ABSOLUTE_FILE_NAME (current_stat_info
.link_name
)
1364 || contains_dot_dot (current_stat_info
.link_name
)))
1365 return create_placeholder_file (file_name
, true, &interdir_made
);
1367 while (symlinkat (current_stat_info
.link_name
, chdir_fd
, file_name
) != 0)
1368 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1377 symlink_error (current_stat_info
.link_name
, file_name
);
1381 set_stat (file_name
, ¤t_stat_info
, -1, 0, 0,
1382 SYMTYPE
, false, AT_SYMLINK_NOFOLLOW
);
1386 static int warned_once
;
1391 WARNOPT (WARN_SYMLINK_CAST
,
1393 _("Attempting extraction of symbolic links as hard links")));
1395 return extract_link (file_name
, typeflag
);
1399 #if S_IFCHR || S_IFBLK
1401 extract_node (char *file_name
, int typeflag
)
1403 bool interdir_made
= false;
1404 mode_t mode
= (current_stat_info
.stat
.st_mode
& (MODE_RWX
| S_IFBLK
| S_IFCHR
)
1405 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
1407 while (mknodat (chdir_fd
, file_name
, mode
, current_stat_info
.stat
.st_rdev
)
1409 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1418 mknod_error (file_name
);
1422 set_stat (file_name
, ¤t_stat_info
, -1,
1423 mode
& ~ current_umask
, MODE_RWX
,
1424 typeflag
, false, AT_SYMLINK_NOFOLLOW
);
1429 #if HAVE_MKFIFO || defined mkfifo
1431 extract_fifo (char *file_name
, int typeflag
)
1433 bool interdir_made
= false;
1434 mode_t mode
= (current_stat_info
.stat
.st_mode
& MODE_RWX
1435 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
1437 while (mkfifoat (chdir_fd
, file_name
, mode
) != 0)
1438 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1447 mkfifo_error (file_name
);
1451 set_stat (file_name
, ¤t_stat_info
, -1,
1452 mode
& ~ current_umask
, MODE_RWX
,
1453 typeflag
, false, AT_SYMLINK_NOFOLLOW
);
1459 extract_volhdr (char *file_name
, int typeflag
)
1466 extract_failure (char *file_name
, int typeflag
)
1472 extract_skip (char *file_name
, int typeflag
)
1478 typedef int (*tar_extractor_t
) (char *file_name
, int typeflag
);
1482 /* Prepare to extract a file. Find extractor function.
1483 Return zero if extraction should not proceed. */
1486 prepare_to_extract (char const *file_name
, int typeflag
, tar_extractor_t
*fun
)
1490 if (EXTRACT_OVER_PIPE
)
1493 /* Select the extractor */
1496 case GNUTYPE_SPARSE
:
1497 *fun
= extract_file
;
1504 /* Appears to be a file. But BSD tar uses the convention that a slash
1505 suffix means a directory. */
1506 if (current_stat_info
.had_trailing_slash
)
1510 *fun
= extract_file
;
1516 *fun
= extract_symlink
;
1520 *fun
= extract_link
;
1525 current_stat_info
.stat
.st_mode
|= S_IFCHR
;
1526 *fun
= extract_node
;
1532 current_stat_info
.stat
.st_mode
|= S_IFBLK
;
1533 *fun
= extract_node
;
1537 #if HAVE_MKFIFO || defined mkfifo
1539 *fun
= extract_fifo
;
1544 case GNUTYPE_DUMPDIR
:
1546 if (current_stat_info
.is_dumpdir
)
1547 delay_directory_restore_option
= true;
1550 case GNUTYPE_VOLHDR
:
1551 *fun
= extract_volhdr
;
1554 case GNUTYPE_MULTIVOL
:
1556 _("%s: Cannot extract -- file is continued from another volume"),
1557 quotearg_colon (current_stat_info
.file_name
)));
1558 *fun
= extract_skip
;
1561 case GNUTYPE_LONGNAME
:
1562 case GNUTYPE_LONGLINK
:
1563 ERROR ((0, 0, _("Unexpected long name header")));
1564 *fun
= extract_failure
;
1568 WARNOPT (WARN_UNKNOWN_CAST
,
1570 _("%s: Unknown file type '%c', extracted as normal file"),
1571 quotearg_colon (file_name
), typeflag
));
1572 *fun
= extract_file
;
1575 /* Determine whether the extraction should proceed */
1579 switch (old_files_option
)
1581 case UNLINK_FIRST_OLD_FILES
:
1582 if (!remove_any_file (file_name
,
1583 recursive_unlink_option
? RECURSIVE_REMOVE_OPTION
1584 : ORDINARY_REMOVE_OPTION
)
1585 && errno
&& errno
!= ENOENT
)
1587 unlink_error (file_name
);
1592 case KEEP_NEWER_FILES
:
1593 if (file_newer_p (file_name
, 0, ¤t_stat_info
))
1595 WARNOPT (WARN_IGNORE_NEWER
,
1596 (0, 0, _("Current %s is newer or same age"),
1597 quote (file_name
)));
1609 /* Extract a file from the archive. */
1611 extract_archive (void)
1614 tar_extractor_t fun
;
1616 fatal_exit_hook
= extract_finish
;
1618 set_next_block_after (current_header
);
1620 if (!current_stat_info
.file_name
[0]
1621 || (interactive_option
1622 && !confirm ("extract", current_stat_info
.file_name
)))
1628 /* Print the block from current_header and current_stat. */
1630 print_header (¤t_stat_info
, current_header
, -1);
1632 /* Restore stats for all non-ancestor directories, unless
1633 it is an incremental archive.
1634 (see NOTICE in the comment to delay_set_stat above) */
1635 if (!delay_directory_restore_option
)
1637 int dir
= chdir_current
;
1638 apply_nonancestor_delayed_set_stat (current_stat_info
.file_name
, 0);
1642 /* Take a safety backup of a previously existing file. */
1645 if (!maybe_backup_file (current_stat_info
.file_name
, 0))
1648 ERROR ((0, e
, _("%s: Was unable to backup this file"),
1649 quotearg_colon (current_stat_info
.file_name
)));
1654 /* Extract the archive entry according to its type. */
1656 typeflag
= sparse_member_p (¤t_stat_info
) ?
1657 GNUTYPE_SPARSE
: current_header
->header
.typeflag
;
1659 if (prepare_to_extract (current_stat_info
.file_name
, typeflag
, &fun
))
1661 if (fun
&& (*fun
) (current_stat_info
.file_name
, typeflag
)
1663 undo_last_backup ();
1670 /* Extract the links whose final extraction were delayed. */
1672 apply_delayed_links (void)
1674 struct delayed_link
*ds
;
1676 for (ds
= delayed_link_head
; ds
; )
1678 struct string_list
*sources
= ds
->sources
;
1679 char const *valid_source
= 0;
1681 chdir_do (ds
->change_dir
);
1683 for (sources
= ds
->sources
; sources
; sources
= sources
->next
)
1685 char const *source
= sources
->string
;
1688 /* Make sure the placeholder file is still there. If not,
1689 don't create a link, as the placeholder was probably
1690 removed by a later extraction. */
1691 if (fstatat (chdir_fd
, source
, &st
, AT_SYMLINK_NOFOLLOW
) == 0
1692 && st
.st_dev
== ds
->dev
1693 && st
.st_ino
== ds
->ino
1694 && timespec_cmp (get_stat_birthtime (&st
), ds
->birthtime
) == 0)
1696 /* Unlink the placeholder, then create a hard link if possible,
1697 a symbolic link otherwise. */
1698 if (unlinkat (chdir_fd
, source
, 0) != 0)
1699 unlink_error (source
);
1700 else if (valid_source
1701 && (linkat (chdir_fd
, valid_source
, chdir_fd
, source
, 0)
1704 else if (!ds
->is_symlink
)
1706 if (linkat (chdir_fd
, ds
->target
, chdir_fd
, source
, 0) != 0)
1707 link_error (ds
->target
, source
);
1709 else if (symlinkat (ds
->target
, chdir_fd
, source
) != 0)
1710 symlink_error (ds
->target
, source
);
1713 struct tar_stat_info st1
;
1714 st1
.stat
.st_mode
= ds
->mode
;
1715 st1
.stat
.st_uid
= ds
->uid
;
1716 st1
.stat
.st_gid
= ds
->gid
;
1717 st1
.atime
= ds
->atime
;
1718 st1
.mtime
= ds
->mtime
;
1719 st1
.cntx_name
= ds
->cntx_name
;
1720 st1
.acls_a_ptr
= ds
->acls_a_ptr
;
1721 st1
.acls_a_len
= ds
->acls_a_len
;
1722 st1
.acls_d_ptr
= ds
->acls_d_ptr
;
1723 st1
.acls_d_len
= ds
->acls_d_len
;
1724 st1
.xattr_map
= ds
->xattr_map
;
1725 st1
.xattr_map_size
= ds
->xattr_map_size
;
1726 set_stat (source
, &st1
, -1, 0, 0, SYMTYPE
,
1727 false, AT_SYMLINK_NOFOLLOW
);
1728 valid_source
= source
;
1733 for (sources
= ds
->sources
; sources
; )
1735 struct string_list
*next
= sources
->next
;
1740 xheader_xattr_free (ds
->xattr_map
, ds
->xattr_map_size
);
1741 free (ds
->cntx_name
);
1744 struct delayed_link
*next
= ds
->next
;
1750 delayed_link_head
= 0;
1753 /* Finish the extraction of an archive. */
1755 extract_finish (void)
1757 /* First, fix the status of ordinary directories that need fixing. */
1758 apply_nonancestor_delayed_set_stat ("", 0);
1760 /* Then, apply delayed links, so that they don't affect delayed
1761 directory status-setting for ordinary directories. */
1762 apply_delayed_links ();
1764 /* Finally, fix the status of directories that are ancestors
1765 of delayed links. */
1766 apply_nonancestor_delayed_set_stat ("", 1);
1770 rename_directory (char *src
, char *dst
)
1772 if (renameat (chdir_fd
, src
, chdir_fd
, dst
) != 0)
1780 if (make_directories (dst
, &interdir_made
) == 0)
1782 if (renameat (chdir_fd
, src
, chdir_fd
, dst
) == 0)
1789 /* FIXME: Fall back to recursive copying */
1795 ERROR ((0, e
, _("Cannot rename %s to %s"),