1 /* Extract files from a tar archive.
3 Copyright (C) 1988, 1992, 1993, 1994, 1996, 1997, 1998, 1999, 2000,
4 2001, 2003, 2004, 2005, 2006, 2007, 2010 Free Software Foundation, Inc.
6 Written by John Gilmore, on 1985-11-19.
8 This program is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by the
10 Free Software Foundation; either version 3, or (at your option) any later
13 This program is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
16 Public License for more details.
18 You should have received a copy of the GNU General Public License along
19 with this program; if not, write to the Free Software Foundation, Inc.,
20 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
30 static bool we_are_root
; /* true if our effective uid == 0 */
31 static mode_t newdir_umask
; /* umask when creating new directories */
32 static mode_t current_umask
; /* current umask (which is set to 0 if -p) */
34 #define ALL_MODE_BITS ((mode_t) ~ (mode_t) 0)
36 #if ! HAVE_FCHMOD && ! defined fchmod
37 # define fchmod(fd, mode) (errno = ENOSYS, -1)
39 #if ! HAVE_FCHOWN && ! defined fchown
40 # define fchown(fd, uid, gid) (errno = ENOSYS, -1)
43 /* Return true if an error number ERR means the system call is
44 supported in this case. */
48 return ! (err
== ENOSYS
50 || (EOPNOTSUPP
!= ENOTSUP
&& err
== EOPNOTSUPP
));
53 /* List of directories whose statuses we need to extract after we've
54 finished extracting their subsidiary files. If you consider each
55 contiguous subsequence of elements of the form [D]?[^D]*, where [D]
56 represents an element where AFTER_LINKS is nonzero and [^D]
57 represents an element where AFTER_LINKS is zero, then the head
58 of the subsequence has the longest name, and each non-head element
59 in the prefix is an ancestor (in the directory hierarchy) of the
62 struct delayed_set_stat
64 /* Next directory in list. */
65 struct delayed_set_stat
*next
;
67 /* Metadata for this directory. */
70 mode_t mode
; /* The desired mode is MODE & ~ current_umask. */
73 struct timespec atime
;
74 struct timespec mtime
;
76 /* An estimate of the directory's current mode, along with a mask
77 specifying which bits of this estimate are known to be correct.
78 If CURRENT_MODE_MASK is zero, CURRENT_MODE's value doesn't
81 mode_t current_mode_mask
;
83 /* This directory is an intermediate directory that was created
84 as an ancestor of some other directory; it was not mentioned
85 in the archive, so do not set its uid, gid, atime, or mtime,
86 and don't alter its mode outside of MODE_RWX. */
89 /* Whether symbolic links should be followed when accessing the
93 /* Do not set the status of this directory until after delayed
97 /* Directory that the name is relative to. */
100 /* Length and contents of name. */
101 size_t file_name_len
;
105 static struct delayed_set_stat
*delayed_set_stat_head
;
107 /* List of links whose creation we have delayed. */
110 /* The next delayed link in the list. */
111 struct delayed_link
*next
;
113 /* The device, inode number and birthtime of the placeholder.
114 birthtime.tv_nsec is negative if the birthtime is not available.
115 Don't use mtime as this would allow for false matches if some
116 other process removes the placeholder. Don't use ctime as
117 this would cause race conditions and other screwups, e.g.,
118 when restoring hard-linked symlinks. */
121 struct timespec birthtime
;
123 /* True if the link is symbolic. */
126 /* The desired metadata, valid only the link is symbolic. */
130 struct timespec atime
;
131 struct timespec mtime
;
133 /* The directory that the sources and target are relative to. */
136 /* A list of sources for this link. The sources are all to be
137 hard-linked together. */
138 struct string_list
*sources
;
140 /* The desired target of the desired link. */
144 static struct delayed_link
*delayed_link_head
;
148 struct string_list
*next
;
152 /* Set up to extract files. */
156 we_are_root
= geteuid () == 0;
157 same_permissions_option
+= we_are_root
;
158 same_owner_option
+= we_are_root
;
160 /* Option -p clears the kernel umask, so it does not affect proper
161 restoration of file permissions. New intermediate directories will
162 comply with umask at start of program. */
164 newdir_umask
= umask (0);
165 if (0 < same_permissions_option
)
169 umask (newdir_umask
); /* restore the kernel umask */
170 current_umask
= newdir_umask
;
174 /* Use fchmod if possible, fchmodat otherwise. */
176 fd_chmod (int fd
, char const *file
, mode_t mode
, int atflag
)
180 int result
= fchmod (fd
, mode
);
181 if (result
== 0 || implemented (errno
))
184 return fchmodat (chdir_fd
, file
, mode
, atflag
);
187 /* Use fchown if possible, fchownat otherwise. */
189 fd_chown (int fd
, char const *file
, uid_t uid
, gid_t gid
, int atflag
)
193 int result
= fchown (fd
, uid
, gid
);
194 if (result
== 0 || implemented (errno
))
197 return fchownat (chdir_fd
, file
, uid
, gid
, atflag
);
200 /* Use fstat if possible, fstatat otherwise. */
202 fd_stat (int fd
, char const *file
, struct stat
*st
, int atflag
)
206 : fstatat (chdir_fd
, file
, st
, atflag
));
209 /* Set the mode for FILE_NAME to MODE.
210 MODE_MASK specifies the bits of MODE that we care about;
211 thus if MODE_MASK is zero, do nothing.
212 If FD is nonnegative, it is a file descriptor for the file.
213 CURRENT_MODE and CURRENT_MODE_MASK specify information known about
214 the file's current mode, using the style of struct delayed_set_stat.
215 TYPEFLAG specifies the type of the file.
216 ATFLAG specifies the flag to use when statting the file. */
218 set_mode (char const *file_name
,
219 mode_t mode
, mode_t mode_mask
, int fd
,
220 mode_t current_mode
, mode_t current_mode_mask
,
221 char typeflag
, int atflag
)
223 if (((current_mode
^ mode
) | ~ current_mode_mask
) & mode_mask
)
225 if (MODE_ALL
& ~ mode_mask
& ~ current_mode_mask
)
228 if (fd_stat (fd
, file_name
, &st
, atflag
) != 0)
230 stat_error (file_name
);
233 current_mode
= st
.st_mode
;
236 current_mode
&= MODE_ALL
;
237 mode
= (current_mode
& ~ mode_mask
) | (mode
& mode_mask
);
239 if (current_mode
!= mode
)
242 fd_chmod (fd
, file_name
, mode
, atflag
) == 0 ? 0 : errno
;
244 /* On Solaris, chmod may fail if we don't have PRIV_ALL, because
245 setuid-root files would otherwise be a backdoor. See
246 http://opensolaris.org/jive/thread.jspa?threadID=95826
248 if (chmod_errno
== EPERM
&& (mode
& S_ISUID
)
249 && priv_set_restore_linkdir () == 0)
252 fd_chmod (fd
, file_name
, mode
, atflag
) == 0 ? 0 : errno
;
253 priv_set_remove_linkdir ();
256 /* Linux fchmodat does not support AT_SYMLINK_NOFOLLOW, and
257 returns ENOTSUP even when operating on non-symlinks, try
258 again with the flag disabled if it does not appear to be
259 supported and if the file is not a symlink. This
260 introduces a race, alas. */
261 if (atflag
&& typeflag
!= SYMTYPE
&& ! implemented (chmod_errno
))
262 chmod_errno
= fd_chmod (fd
, file_name
, mode
, 0) == 0 ? 0 : errno
;
265 && (typeflag
!= SYMTYPE
|| implemented (chmod_errno
)))
268 chmod_error_details (file_name
, mode
);
274 /* Check time after successfully setting FILE_NAME's time stamp to T. */
276 check_time (char const *file_name
, struct timespec t
)
279 WARNOPT (WARN_TIMESTAMP
,
280 (0, 0, _("%s: implausibly old time stamp %s"),
281 file_name
, tartime (t
, true)));
282 else if (timespec_cmp (volume_start_time
, t
) < 0)
286 if (timespec_cmp (now
, t
) < 0)
288 char buf
[TIMESPEC_STRSIZE_BOUND
];
289 struct timespec diff
;
290 diff
.tv_sec
= t
.tv_sec
- now
.tv_sec
;
291 diff
.tv_nsec
= t
.tv_nsec
- now
.tv_nsec
;
292 if (diff
.tv_nsec
< 0)
294 diff
.tv_nsec
+= BILLION
;
297 WARNOPT (WARN_TIMESTAMP
,
298 (0, 0, _("%s: time stamp %s is %s s in the future"),
299 file_name
, tartime (t
, true), code_timespec (diff
, buf
)));
304 /* Restore stat attributes (owner, group, mode and times) for
305 FILE_NAME, using information given in *ST.
306 If FD is nonnegative, it is a file descriptor for the file.
307 CURRENT_MODE and CURRENT_MODE_MASK specify information known about
308 the file's current mode, using the style of struct delayed_set_stat.
309 TYPEFLAG specifies the type of the file.
310 If INTERDIR, this is an intermediate directory.
311 ATFLAG specifies the flag to use when statting the file. */
314 set_stat (char const *file_name
,
315 struct tar_stat_info
const *st
,
316 int fd
, mode_t current_mode
, mode_t current_mode_mask
,
317 char typeflag
, bool interdir
, int atflag
)
319 /* Do the utime before the chmod because some versions of utime are
320 broken and trash the modes of the file. */
322 if (! touch_option
&& ! interdir
)
324 struct timespec ts
[2];
325 if (incremental_option
)
328 ts
[0].tv_nsec
= UTIME_OMIT
;
331 if (fdutimensat (fd
, chdir_fd
, file_name
, ts
, atflag
) == 0)
333 if (incremental_option
)
334 check_time (file_name
, ts
[0]);
335 check_time (file_name
, ts
[1]);
337 else if (typeflag
!= SYMTYPE
|| implemented (errno
))
338 utime_error (file_name
);
341 if (0 < same_owner_option
&& ! interdir
)
343 /* Some systems allow non-root users to give files away. Once this
344 done, it is not possible anymore to change file permissions.
345 However, setting file permissions now would be incorrect, since
346 they would apply to the wrong user, and there would be a race
347 condition. So, don't use systems that allow non-root users to
349 uid_t uid
= st
->stat
.st_uid
;
350 gid_t gid
= st
->stat
.st_gid
;
352 if (fd_chown (fd
, file_name
, uid
, gid
, atflag
) == 0)
354 /* Changing the owner can clear st_mode bits in some cases. */
355 if ((current_mode
| ~ current_mode_mask
) & S_IXUGO
)
356 current_mode_mask
&= ~ (current_mode
& (S_ISUID
| S_ISGID
));
358 else if (typeflag
!= SYMTYPE
|| implemented (errno
))
359 chown_error_details (file_name
, uid
, gid
);
363 st
->stat
.st_mode
& ~ current_umask
,
364 0 < same_permissions_option
&& ! interdir
? MODE_ALL
: MODE_RWX
,
365 fd
, current_mode
, current_mode_mask
, typeflag
, atflag
);
368 /* For each entry H in the leading prefix of entries in HEAD that do
369 not have after_links marked, mark H and fill in its dev and ino
370 members. Assume HEAD && ! HEAD->after_links. */
372 mark_after_links (struct delayed_set_stat
*head
)
374 struct delayed_set_stat
*h
= head
;
381 if (deref_stat (h
->file_name
, &st
) != 0)
382 stat_error (h
->file_name
);
389 while ((h
= h
->next
) && ! h
->after_links
);
392 /* Remember to restore stat attributes (owner, group, mode and times)
393 for the directory FILE_NAME, using information given in *ST,
394 once we stop extracting files into that directory.
396 If ST is null, merely create a placeholder node for an intermediate
397 directory that was created by make_directories.
399 NOTICE: this works only if the archive has usual member order, i.e.
400 directory, then the files in that directory. Incremental archive have
401 somewhat reversed order: first go subdirectories, then all other
402 members. To help cope with this case the variable
403 delay_directory_restore_option is set by prepare_to_extract.
405 If an archive was explicitely created so that its member order is
406 reversed, some directory timestamps can be restored incorrectly,
408 tar --no-recursion -cf archive dir dir/file1 foo dir/file2
411 delay_set_stat (char const *file_name
, struct tar_stat_info
const *st
,
412 mode_t current_mode
, mode_t current_mode_mask
,
413 mode_t mode
, int atflag
)
415 size_t file_name_len
= strlen (file_name
);
416 struct delayed_set_stat
*data
=
417 xmalloc (offsetof (struct delayed_set_stat
, file_name
)
418 + file_name_len
+ 1);
419 data
->next
= delayed_set_stat_head
;
423 data
->dev
= st
->stat
.st_dev
;
424 data
->ino
= st
->stat
.st_ino
;
425 data
->uid
= st
->stat
.st_uid
;
426 data
->gid
= st
->stat
.st_gid
;
427 data
->atime
= st
->atime
;
428 data
->mtime
= st
->mtime
;
430 data
->file_name_len
= file_name_len
;
431 data
->current_mode
= current_mode
;
432 data
->current_mode_mask
= current_mode_mask
;
433 data
->interdir
= ! st
;
434 data
->atflag
= atflag
;
435 data
->after_links
= 0;
436 data
->change_dir
= chdir_current
;
437 strcpy (data
->file_name
, file_name
);
438 delayed_set_stat_head
= data
;
439 if (must_be_dot_or_slash (file_name
))
440 mark_after_links (data
);
443 /* Update the delayed_set_stat info for an intermediate directory
444 created within the file name of DIR. The intermediate directory turned
445 out to be the same as this directory, e.g. due to ".." or symbolic
446 links. *DIR_STAT_INFO is the status of the directory. */
448 repair_delayed_set_stat (char const *dir
,
449 struct stat
const *dir_stat_info
)
451 struct delayed_set_stat
*data
;
452 for (data
= delayed_set_stat_head
; data
; data
= data
->next
)
455 if (fstatat (chdir_fd
, data
->file_name
, &st
, data
->atflag
) != 0)
457 stat_error (data
->file_name
);
461 if (st
.st_dev
== dir_stat_info
->st_dev
462 && st
.st_ino
== dir_stat_info
->st_ino
)
464 data
->dev
= current_stat_info
.stat
.st_dev
;
465 data
->ino
= current_stat_info
.stat
.st_ino
;
466 data
->mode
= current_stat_info
.stat
.st_mode
;
467 data
->uid
= current_stat_info
.stat
.st_uid
;
468 data
->gid
= current_stat_info
.stat
.st_gid
;
469 data
->atime
= current_stat_info
.atime
;
470 data
->mtime
= current_stat_info
.mtime
;
471 data
->current_mode
= st
.st_mode
;
472 data
->current_mode_mask
= ALL_MODE_BITS
;
473 data
->interdir
= false;
478 ERROR ((0, 0, _("%s: Unexpected inconsistency when making directory"),
479 quotearg_colon (dir
)));
482 /* After a file/link/directory creation has failed, see if
483 it's because some required directory was not present, and if so,
484 create all required directories. Return zero if all the required
485 directories were created, nonzero (issuing a diagnostic) otherwise.
486 Set *INTERDIR_MADE if at least one directory was created. */
488 make_directories (char *file_name
, bool *interdir_made
)
490 char *cursor0
= file_name
+ FILE_SYSTEM_PREFIX_LEN (file_name
);
491 char *cursor
; /* points into the file name */
493 for (cursor
= cursor0
; *cursor
; cursor
++)
499 if (! ISSLASH (*cursor
))
502 /* Avoid mkdir of empty string, if leading or double '/'. */
504 if (cursor
== cursor0
|| ISSLASH (cursor
[-1]))
507 /* Avoid mkdir where last part of file name is "." or "..". */
509 if (cursor
[-1] == '.'
510 && (cursor
== cursor0
+ 1 || ISSLASH (cursor
[-2])
511 || (cursor
[-2] == '.'
512 && (cursor
== cursor0
+ 2 || ISSLASH (cursor
[-3])))))
515 *cursor
= '\0'; /* truncate the name there */
516 desired_mode
= MODE_RWX
& ~ newdir_umask
;
517 mode
= desired_mode
| (we_are_root
? 0 : MODE_WXUSR
);
518 status
= mkdirat (chdir_fd
, file_name
, mode
);
522 /* Create a struct delayed_set_stat even if
523 mode == desired_mode, because
524 repair_delayed_set_stat may need to update the struct. */
525 delay_set_stat (file_name
,
526 0, mode
& ~ current_umask
, MODE_RWX
,
527 desired_mode
, AT_SYMLINK_NOFOLLOW
);
529 print_for_mkdir (file_name
, cursor
- file_name
, desired_mode
);
530 *interdir_made
= true;
532 else if (errno
== EEXIST
)
536 /* Check whether the desired file exists. Even when the
537 file exists, mkdir can fail with some errno value E other
538 than EEXIST, so long as E describes an error condition
539 that also applies. */
542 status
= fstatat (chdir_fd
, file_name
, &st
, 0);
546 mkdir_error (file_name
);
558 /* Return true if FILE_NAME (with status *STP, if STP) is not a
559 directory, and has a time stamp newer than (or equal to) that of
562 file_newer_p (const char *file_name
, struct stat
const *stp
,
563 struct tar_stat_info
*tar_stat
)
569 if (deref_stat (file_name
, &st
) != 0)
573 stat_warn (file_name
);
574 /* Be safer: if the file exists, assume it is newer. */
582 return (! S_ISDIR (stp
->st_mode
)
583 && tar_timespec_cmp (tar_stat
->mtime
, get_stat_mtime (stp
)) <= 0);
588 #define RECOVER_SKIP 2
590 /* Attempt repairing what went wrong with the extraction. Delete an
591 already existing file or create missing intermediate directories.
592 Return RECOVER_OK if we somewhat increased our chances at a successful
593 extraction, RECOVER_NO if there are no chances, and RECOVER_SKIP if the
594 caller should skip extraction of that member. The value of errno is
595 properly restored on returning RECOVER_NO.
597 If REGULAR, the caller was trying to extract onto a regular file.
599 Set *INTERDIR_MADE if an intermediate directory is made as part of
600 the recovery process. */
603 maybe_recoverable (char *file_name
, bool regular
, bool *interdir_made
)
607 struct stat
const *stp
= 0;
616 /* With open ("symlink", O_NOFOLLOW|...), POSIX says errno == ELOOP,
617 but some operating systems do not conform to the standard. */
619 /* NetBSD uses errno == EFTYPE; see <http://gnats.netbsd.org/43154>. */
622 /* FreeBSD 8.1 uses errno == EMLINK. */
624 /* Tru64 5.1B uses errno == ENOTSUP. */
628 || old_files_option
!= OVERWRITE_OLD_FILES
|| dereference_option
)
630 if (strchr (file_name
, '/'))
632 if (deref_stat (file_name
, &st
) != 0)
637 /* The caller tried to open a symbolic link with O_NOFOLLOW.
638 Fall through, treating it as an already-existing file. */
641 /* Remove an old file, if the options allow this. */
643 switch (old_files_option
)
646 WARNOPT (WARN_EXISTING_FILE
,
647 (0, 0, _("%s: skipping existing file"), file_name
));
650 case KEEP_NEWER_FILES
:
651 if (file_newer_p (file_name
, stp
, ¤t_stat_info
))
655 case DEFAULT_OLD_FILES
:
656 case NO_OVERWRITE_DIR_OLD_FILES
:
657 case OVERWRITE_OLD_FILES
:
658 if (0 < remove_any_file (file_name
, ORDINARY_REMOVE_OPTION
))
662 case UNLINK_FIRST_OLD_FILES
:
667 /* Attempt creating missing intermediate directories. */
668 if (make_directories (file_name
, interdir_made
) == 0 && *interdir_made
)
673 /* Just say we can't do anything about it... */
681 /* Fix the statuses of all directories whose statuses need fixing, and
682 which are not ancestors of FILE_NAME. If AFTER_LINKS is
683 nonzero, do this for all such directories; otherwise, stop at the
684 first directory that is marked to be fixed up only after delayed
685 links are applied. */
687 apply_nonancestor_delayed_set_stat (char const *file_name
, bool after_links
)
689 size_t file_name_len
= strlen (file_name
);
690 bool check_for_renamed_directories
= 0;
692 while (delayed_set_stat_head
)
694 struct delayed_set_stat
*data
= delayed_set_stat_head
;
695 bool skip_this_one
= 0;
697 mode_t current_mode
= data
->current_mode
;
698 mode_t current_mode_mask
= data
->current_mode_mask
;
700 check_for_renamed_directories
|= data
->after_links
;
702 if (after_links
< data
->after_links
703 || (data
->file_name_len
< file_name_len
704 && file_name
[data
->file_name_len
]
705 && (ISSLASH (file_name
[data
->file_name_len
])
706 || ISSLASH (file_name
[data
->file_name_len
- 1]))
707 && memcmp (file_name
, data
->file_name
, data
->file_name_len
) == 0))
710 chdir_do (data
->change_dir
);
712 if (check_for_renamed_directories
)
714 if (fstatat (chdir_fd
, data
->file_name
, &st
, data
->atflag
) != 0)
716 stat_error (data
->file_name
);
721 current_mode
= st
.st_mode
;
722 current_mode_mask
= ALL_MODE_BITS
;
723 if (! (st
.st_dev
== data
->dev
&& st
.st_ino
== data
->ino
))
726 _("%s: Directory renamed before its status could be extracted"),
727 quotearg_colon (data
->file_name
)));
735 struct tar_stat_info sb
;
736 sb
.stat
.st_mode
= data
->mode
;
737 sb
.stat
.st_uid
= data
->uid
;
738 sb
.stat
.st_gid
= data
->gid
;
739 sb
.atime
= data
->atime
;
740 sb
.mtime
= data
->mtime
;
741 set_stat (data
->file_name
, &sb
,
742 -1, current_mode
, current_mode_mask
,
743 DIRTYPE
, data
->interdir
, data
->atflag
);
746 delayed_set_stat_head
= data
->next
;
753 /* Extractor functions for various member types */
756 extract_dir (char *file_name
, int typeflag
)
760 mode_t current_mode
= 0;
761 mode_t current_mode_mask
= 0;
763 bool interdir_made
= false;
765 /* Save 'root device' to avoid purging mount points. */
766 if (one_file_system_option
&& root_device
== 0)
770 if (fstatat (chdir_fd
, ".", &st
, 0) != 0)
773 root_device
= st
.st_dev
;
776 if (incremental_option
)
777 /* Read the entry and delete files that aren't listed in the archive. */
778 purge_directory (file_name
);
779 else if (typeflag
== GNUTYPE_DUMPDIR
)
782 /* If ownership or permissions will be restored later, create the
783 directory with restrictive permissions at first, so that in the
784 meantime processes owned by other users do not inadvertently
785 create files under this directory that inherit the wrong owner,
786 group, or permissions from the directory. If not root, though,
787 make the directory writeable and searchable at first, so that
788 files can be created under it. */
789 mode
= ((current_stat_info
.stat
.st_mode
790 & (0 < same_owner_option
|| 0 < same_permissions_option
793 | (we_are_root
? 0 : MODE_WXUSR
));
797 status
= mkdirat (chdir_fd
, file_name
, mode
);
800 current_mode
= mode
& ~ current_umask
;
801 current_mode_mask
= MODE_RWX
;
802 atflag
= AT_SYMLINK_NOFOLLOW
;
808 || old_files_option
== DEFAULT_OLD_FILES
809 || old_files_option
== OVERWRITE_OLD_FILES
))
812 if (deref_stat (file_name
, &st
) == 0)
814 current_mode
= st
.st_mode
;
815 current_mode_mask
= ALL_MODE_BITS
;
817 if (S_ISDIR (current_mode
))
821 repair_delayed_set_stat (file_name
, &st
);
830 switch (maybe_recoverable (file_name
, false, &interdir_made
))
841 mkdir_error (file_name
);
850 || old_files_option
== DEFAULT_OLD_FILES
851 || old_files_option
== OVERWRITE_OLD_FILES
)
852 delay_set_stat (file_name
, ¤t_stat_info
,
853 current_mode
, current_mode_mask
,
854 current_stat_info
.stat
.st_mode
, atflag
);
861 open_output_file (char const *file_name
, int typeflag
, mode_t mode
,
862 mode_t
*current_mode
, mode_t
*current_mode_mask
)
865 bool overwriting_old_files
= old_files_option
== OVERWRITE_OLD_FILES
;
866 int openflag
= (O_WRONLY
| O_BINARY
| O_CLOEXEC
| O_NOCTTY
| O_NONBLOCK
868 | (overwriting_old_files
869 ? O_TRUNC
| (dereference_option
? 0 : O_NOFOLLOW
)
872 if (typeflag
== CONTTYPE
)
874 static int conttype_diagnosed
;
876 if (!conttype_diagnosed
)
878 conttype_diagnosed
= 1;
879 WARNOPT (WARN_CONTIGUOUS_CAST
,
880 (0, 0, _("Extracting contiguous files as regular files")));
884 /* If O_NOFOLLOW is needed but does not work, check for a symlink
885 separately. There's a race condition, but that cannot be avoided
886 on hosts lacking O_NOFOLLOW. */
887 if (! O_NOFOLLOW
&& overwriting_old_files
&& ! dereference_option
)
890 if (fstatat (chdir_fd
, file_name
, &st
, AT_SYMLINK_NOFOLLOW
) == 0
891 && S_ISLNK (st
.st_mode
))
898 fd
= openat (chdir_fd
, file_name
, openflag
, mode
);
901 if (overwriting_old_files
)
904 if (fstat (fd
, &st
) != 0)
911 if (! S_ISREG (st
.st_mode
))
917 *current_mode
= st
.st_mode
;
918 *current_mode_mask
= ALL_MODE_BITS
;
922 *current_mode
= mode
& ~ current_umask
;
923 *current_mode_mask
= MODE_RWX
;
931 extract_file (char *file_name
, int typeflag
)
935 union block
*data_block
;
939 bool interdir_made
= false;
940 mode_t mode
= (current_stat_info
.stat
.st_mode
& MODE_RWX
941 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
942 mode_t current_mode
= 0;
943 mode_t current_mode_mask
= 0;
945 if (to_stdout_option
)
947 else if (to_command_option
)
949 fd
= sys_exec_command (file_name
, 'f', ¤t_stat_info
);
958 while ((fd
= open_output_file (file_name
, typeflag
, mode
,
959 ¤t_mode
, ¤t_mode_mask
))
962 int recover
= maybe_recoverable (file_name
, true, &interdir_made
);
963 if (recover
!= RECOVER_OK
)
966 if (recover
== RECOVER_SKIP
)
968 open_error (file_name
);
974 mv_begin_read (¤t_stat_info
);
975 if (current_stat_info
.is_sparse
)
976 sparse_extract_file (fd
, ¤t_stat_info
, &size
);
978 for (size
= current_stat_info
.stat
.st_size
; size
> 0; )
982 /* Locate data, determine max length writeable, write it,
983 block that we have used the data, then check if the write
986 data_block
= find_next_block ();
989 ERROR ((0, 0, _("Unexpected EOF in archive")));
990 break; /* FIXME: What happens, then? */
993 written
= available_space_after (data_block
);
998 count
= full_write (fd
, data_block
->buffer
, written
);
1001 set_next_block_after ((union block
*)
1002 (data_block
->buffer
+ written
- 1));
1003 if (count
!= written
)
1005 if (!to_command_option
)
1006 write_error_details (file_name
, count
, written
);
1007 /* FIXME: shouldn't we restore from backup? */
1016 /* If writing to stdout, don't try to do anything to the filename;
1017 it doesn't exist, or we don't want to touch it anyway. */
1019 if (to_stdout_option
)
1022 if (! to_command_option
)
1023 set_stat (file_name
, ¤t_stat_info
, fd
,
1024 current_mode
, current_mode_mask
, typeflag
, false,
1025 (old_files_option
== OVERWRITE_OLD_FILES
1026 ? 0 : AT_SYMLINK_NOFOLLOW
));
1028 status
= close (fd
);
1030 close_error (file_name
);
1032 if (to_command_option
)
1033 sys_wait_command ();
1038 /* Create a placeholder file with name FILE_NAME, which will be
1039 replaced after other extraction is done by a symbolic link if
1040 IS_SYMLINK is true, and by a hard link otherwise. Set
1041 *INTERDIR_MADE if an intermediate directory is made in the
1045 create_placeholder_file (char *file_name
, bool is_symlink
, bool *interdir_made
)
1050 while ((fd
= openat (chdir_fd
, file_name
, O_WRONLY
| O_CREAT
| O_EXCL
, 0)) < 0)
1052 switch (maybe_recoverable (file_name
, false, interdir_made
))
1061 open_error (file_name
);
1066 if (fstat (fd
, &st
) != 0)
1068 stat_error (file_name
);
1071 else if (close (fd
) != 0)
1072 close_error (file_name
);
1075 struct delayed_set_stat
*h
;
1076 struct delayed_link
*p
=
1077 xmalloc (offsetof (struct delayed_link
, target
)
1078 + strlen (current_stat_info
.link_name
)
1080 p
->next
= delayed_link_head
;
1081 delayed_link_head
= p
;
1084 p
->birthtime
= get_stat_birthtime (&st
);
1085 p
->is_symlink
= is_symlink
;
1088 p
->mode
= current_stat_info
.stat
.st_mode
;
1089 p
->uid
= current_stat_info
.stat
.st_uid
;
1090 p
->gid
= current_stat_info
.stat
.st_gid
;
1091 p
->atime
= current_stat_info
.atime
;
1092 p
->mtime
= current_stat_info
.mtime
;
1094 p
->change_dir
= chdir_current
;
1095 p
->sources
= xmalloc (offsetof (struct string_list
, string
)
1096 + strlen (file_name
) + 1);
1097 p
->sources
->next
= 0;
1098 strcpy (p
->sources
->string
, file_name
);
1099 strcpy (p
->target
, current_stat_info
.link_name
);
1101 h
= delayed_set_stat_head
;
1102 if (h
&& ! h
->after_links
1103 && strncmp (file_name
, h
->file_name
, h
->file_name_len
) == 0
1104 && ISSLASH (file_name
[h
->file_name_len
])
1105 && (last_component (file_name
) == file_name
+ h
->file_name_len
+ 1))
1106 mark_after_links (h
);
1115 extract_link (char *file_name
, int typeflag
)
1117 bool interdir_made
= false;
1118 char const *link_name
;
1121 link_name
= current_stat_info
.link_name
;
1123 if (! absolute_names_option
&& contains_dot_dot (link_name
))
1124 return create_placeholder_file (file_name
, false, &interdir_made
);
1128 struct stat st1
, st2
;
1130 int status
= linkat (chdir_fd
, link_name
, chdir_fd
, file_name
, 0);
1135 struct delayed_link
*ds
= delayed_link_head
;
1137 && fstatat (chdir_fd
, link_name
, &st1
, AT_SYMLINK_NOFOLLOW
) == 0)
1138 for (; ds
; ds
= ds
->next
)
1139 if (ds
->change_dir
== chdir_current
1140 && ds
->dev
== st1
.st_dev
1141 && ds
->ino
== st1
.st_ino
1142 && (timespec_cmp (ds
->birthtime
, get_stat_birthtime (&st1
))
1145 struct string_list
*p
= xmalloc (offsetof (struct string_list
, string
)
1146 + strlen (file_name
) + 1);
1147 strcpy (p
->string
, file_name
);
1148 p
->next
= ds
->sources
;
1154 else if ((e
== EEXIST
&& strcmp (link_name
, file_name
) == 0)
1155 || ((fstatat (chdir_fd
, link_name
, &st1
, AT_SYMLINK_NOFOLLOW
)
1157 && (fstatat (chdir_fd
, file_name
, &st2
, AT_SYMLINK_NOFOLLOW
)
1159 && st1
.st_dev
== st2
.st_dev
1160 && st1
.st_ino
== st2
.st_ino
))
1165 while ((rc
= maybe_recoverable (file_name
, false, &interdir_made
))
1168 if (rc
== RECOVER_SKIP
)
1170 if (!(incremental_option
&& errno
== EEXIST
))
1172 link_error (link_name
, file_name
);
1179 extract_symlink (char *file_name
, int typeflag
)
1182 bool interdir_made
= false;
1184 if (! absolute_names_option
1185 && (IS_ABSOLUTE_FILE_NAME (current_stat_info
.link_name
)
1186 || contains_dot_dot (current_stat_info
.link_name
)))
1187 return create_placeholder_file (file_name
, true, &interdir_made
);
1189 while (symlinkat (current_stat_info
.link_name
, chdir_fd
, file_name
) != 0)
1190 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1199 symlink_error (current_stat_info
.link_name
, file_name
);
1203 set_stat (file_name
, ¤t_stat_info
, -1, 0, 0,
1204 SYMTYPE
, false, AT_SYMLINK_NOFOLLOW
);
1208 static int warned_once
;
1213 WARNOPT (WARN_SYMBOLIC_CAST
,
1215 _("Attempting extraction of symbolic links as hard links")));
1217 return extract_link (file_name
, typeflag
);
1221 #if S_IFCHR || S_IFBLK
1223 extract_node (char *file_name
, int typeflag
)
1225 bool interdir_made
= false;
1226 mode_t mode
= (current_stat_info
.stat
.st_mode
& (MODE_RWX
| S_IFBLK
| S_IFCHR
)
1227 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
1229 while (mknodat (chdir_fd
, file_name
, mode
, current_stat_info
.stat
.st_rdev
)
1231 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1240 mknod_error (file_name
);
1244 set_stat (file_name
, ¤t_stat_info
, -1,
1245 mode
& ~ current_umask
, MODE_RWX
,
1246 typeflag
, false, AT_SYMLINK_NOFOLLOW
);
1251 #if HAVE_MKFIFO || defined mkfifo
1253 extract_fifo (char *file_name
, int typeflag
)
1255 bool interdir_made
= false;
1256 mode_t mode
= (current_stat_info
.stat
.st_mode
& MODE_RWX
1257 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
1259 while (mkfifoat (chdir_fd
, file_name
, mode
) != 0)
1260 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1269 mkfifo_error (file_name
);
1273 set_stat (file_name
, ¤t_stat_info
, -1,
1274 mode
& ~ current_umask
, MODE_RWX
,
1275 typeflag
, false, AT_SYMLINK_NOFOLLOW
);
1281 extract_volhdr (char *file_name
, int typeflag
)
1288 extract_failure (char *file_name
, int typeflag
)
1293 typedef int (*tar_extractor_t
) (char *file_name
, int typeflag
);
1297 /* Prepare to extract a file. Find extractor function.
1298 Return zero if extraction should not proceed. */
1301 prepare_to_extract (char const *file_name
, int typeflag
, tar_extractor_t
*fun
)
1305 if (EXTRACT_OVER_PIPE
)
1308 /* Select the extractor */
1311 case GNUTYPE_SPARSE
:
1312 *fun
= extract_file
;
1319 /* Appears to be a file. But BSD tar uses the convention that a slash
1320 suffix means a directory. */
1321 if (current_stat_info
.had_trailing_slash
)
1325 *fun
= extract_file
;
1331 *fun
= extract_symlink
;
1335 *fun
= extract_link
;
1340 current_stat_info
.stat
.st_mode
|= S_IFCHR
;
1341 *fun
= extract_node
;
1347 current_stat_info
.stat
.st_mode
|= S_IFBLK
;
1348 *fun
= extract_node
;
1352 #if HAVE_MKFIFO || defined mkfifo
1354 *fun
= extract_fifo
;
1359 case GNUTYPE_DUMPDIR
:
1361 if (current_stat_info
.is_dumpdir
)
1362 delay_directory_restore_option
= true;
1365 case GNUTYPE_VOLHDR
:
1366 *fun
= extract_volhdr
;
1369 case GNUTYPE_MULTIVOL
:
1371 _("%s: Cannot extract -- file is continued from another volume"),
1372 quotearg_colon (current_stat_info
.file_name
)));
1373 *fun
= extract_failure
;
1376 case GNUTYPE_LONGNAME
:
1377 case GNUTYPE_LONGLINK
:
1378 ERROR ((0, 0, _("Unexpected long name header")));
1379 *fun
= extract_failure
;
1383 WARNOPT (WARN_UNKNOWN_CAST
,
1385 _("%s: Unknown file type `%c', extracted as normal file"),
1386 quotearg_colon (file_name
), typeflag
));
1387 *fun
= extract_file
;
1390 /* Determine whether the extraction should proceed */
1394 switch (old_files_option
)
1396 case UNLINK_FIRST_OLD_FILES
:
1397 if (!remove_any_file (file_name
,
1398 recursive_unlink_option
? RECURSIVE_REMOVE_OPTION
1399 : ORDINARY_REMOVE_OPTION
)
1400 && errno
&& errno
!= ENOENT
)
1402 unlink_error (file_name
);
1407 case KEEP_NEWER_FILES
:
1408 if (file_newer_p (file_name
, 0, ¤t_stat_info
))
1410 WARNOPT (WARN_IGNORE_NEWER
,
1411 (0, 0, _("Current %s is newer or same age"),
1412 quote (file_name
)));
1424 /* Extract a file from the archive. */
1426 extract_archive (void)
1429 tar_extractor_t fun
;
1431 fatal_exit_hook
= extract_finish
;
1433 set_next_block_after (current_header
);
1435 if (!current_stat_info
.file_name
[0]
1436 || (interactive_option
1437 && !confirm ("extract", current_stat_info
.file_name
)))
1443 /* Print the block from current_header and current_stat. */
1445 print_header (¤t_stat_info
, current_header
, -1);
1447 /* Restore stats for all non-ancestor directories, unless
1448 it is an incremental archive.
1449 (see NOTICE in the comment to delay_set_stat above) */
1450 if (!delay_directory_restore_option
)
1452 int dir
= chdir_current
;
1453 apply_nonancestor_delayed_set_stat (current_stat_info
.file_name
, 0);
1457 /* Take a safety backup of a previously existing file. */
1460 if (!maybe_backup_file (current_stat_info
.file_name
, 0))
1463 ERROR ((0, e
, _("%s: Was unable to backup this file"),
1464 quotearg_colon (current_stat_info
.file_name
)));
1469 /* Extract the archive entry according to its type. */
1471 typeflag
= sparse_member_p (¤t_stat_info
) ?
1472 GNUTYPE_SPARSE
: current_header
->header
.typeflag
;
1474 if (prepare_to_extract (current_stat_info
.file_name
, typeflag
, &fun
))
1476 if (fun
&& (*fun
) (current_stat_info
.file_name
, typeflag
)
1478 undo_last_backup ();
1485 /* Extract the links whose final extraction were delayed. */
1487 apply_delayed_links (void)
1489 struct delayed_link
*ds
;
1491 for (ds
= delayed_link_head
; ds
; )
1493 struct string_list
*sources
= ds
->sources
;
1494 char const *valid_source
= 0;
1496 chdir_do (ds
->change_dir
);
1498 for (sources
= ds
->sources
; sources
; sources
= sources
->next
)
1500 char const *source
= sources
->string
;
1503 /* Make sure the placeholder file is still there. If not,
1504 don't create a link, as the placeholder was probably
1505 removed by a later extraction. */
1506 if (fstatat (chdir_fd
, source
, &st
, AT_SYMLINK_NOFOLLOW
) == 0
1507 && st
.st_dev
== ds
->dev
1508 && st
.st_ino
== ds
->ino
1509 && timespec_cmp (get_stat_birthtime (&st
), ds
->birthtime
) == 0)
1511 /* Unlink the placeholder, then create a hard link if possible,
1512 a symbolic link otherwise. */
1513 if (unlinkat (chdir_fd
, source
, 0) != 0)
1514 unlink_error (source
);
1515 else if (valid_source
1516 && (linkat (chdir_fd
, valid_source
, chdir_fd
, source
, 0)
1519 else if (!ds
->is_symlink
)
1521 if (linkat (chdir_fd
, ds
->target
, chdir_fd
, source
, 0) != 0)
1522 link_error (ds
->target
, source
);
1524 else if (symlinkat (ds
->target
, chdir_fd
, source
) != 0)
1525 symlink_error (ds
->target
, source
);
1528 struct tar_stat_info st1
;
1529 st1
.stat
.st_mode
= ds
->mode
;
1530 st1
.stat
.st_uid
= ds
->uid
;
1531 st1
.stat
.st_gid
= ds
->gid
;
1532 st1
.atime
= ds
->atime
;
1533 st1
.mtime
= ds
->mtime
;
1534 set_stat (source
, &st1
, -1, 0, 0, SYMTYPE
,
1535 false, AT_SYMLINK_NOFOLLOW
);
1536 valid_source
= source
;
1541 for (sources
= ds
->sources
; sources
; )
1543 struct string_list
*next
= sources
->next
;
1549 struct delayed_link
*next
= ds
->next
;
1555 delayed_link_head
= 0;
1558 /* Finish the extraction of an archive. */
1560 extract_finish (void)
1562 /* First, fix the status of ordinary directories that need fixing. */
1563 apply_nonancestor_delayed_set_stat ("", 0);
1565 /* Then, apply delayed links, so that they don't affect delayed
1566 directory status-setting for ordinary directories. */
1567 apply_delayed_links ();
1569 /* Finally, fix the status of directories that are ancestors
1570 of delayed links. */
1571 apply_nonancestor_delayed_set_stat ("", 1);
1575 rename_directory (char *src
, char *dst
)
1577 if (renameat (chdir_fd
, src
, chdir_fd
, dst
) != 0)
1585 if (make_directories (dst
, &interdir_made
) == 0)
1587 if (renameat (chdir_fd
, src
, chdir_fd
, dst
) == 0)
1594 /* FIXME: Fall back to recursive copying */
1600 ERROR ((0, e
, _("Cannot rename %s to %s"),