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
)
648 case KEEP_NEWER_FILES
:
649 if (file_newer_p (file_name
, stp
, ¤t_stat_info
))
653 case DEFAULT_OLD_FILES
:
654 case NO_OVERWRITE_DIR_OLD_FILES
:
655 case OVERWRITE_OLD_FILES
:
656 if (0 < remove_any_file (file_name
, ORDINARY_REMOVE_OPTION
))
660 case UNLINK_FIRST_OLD_FILES
:
665 /* Attempt creating missing intermediate directories. */
666 if (make_directories (file_name
, interdir_made
) == 0 && *interdir_made
)
671 /* Just say we can't do anything about it... */
679 /* Fix the statuses of all directories whose statuses need fixing, and
680 which are not ancestors of FILE_NAME. If AFTER_LINKS is
681 nonzero, do this for all such directories; otherwise, stop at the
682 first directory that is marked to be fixed up only after delayed
683 links are applied. */
685 apply_nonancestor_delayed_set_stat (char const *file_name
, bool after_links
)
687 size_t file_name_len
= strlen (file_name
);
688 bool check_for_renamed_directories
= 0;
690 while (delayed_set_stat_head
)
692 struct delayed_set_stat
*data
= delayed_set_stat_head
;
693 bool skip_this_one
= 0;
695 mode_t current_mode
= data
->current_mode
;
696 mode_t current_mode_mask
= data
->current_mode_mask
;
698 check_for_renamed_directories
|= data
->after_links
;
700 if (after_links
< data
->after_links
701 || (data
->file_name_len
< file_name_len
702 && file_name
[data
->file_name_len
]
703 && (ISSLASH (file_name
[data
->file_name_len
])
704 || ISSLASH (file_name
[data
->file_name_len
- 1]))
705 && memcmp (file_name
, data
->file_name
, data
->file_name_len
) == 0))
708 chdir_do (data
->change_dir
);
710 if (check_for_renamed_directories
)
712 if (fstatat (chdir_fd
, data
->file_name
, &st
, data
->atflag
) != 0)
714 stat_error (data
->file_name
);
719 current_mode
= st
.st_mode
;
720 current_mode_mask
= ALL_MODE_BITS
;
721 if (! (st
.st_dev
== data
->dev
&& st
.st_ino
== data
->ino
))
724 _("%s: Directory renamed before its status could be extracted"),
725 quotearg_colon (data
->file_name
)));
733 struct tar_stat_info sb
;
734 sb
.stat
.st_mode
= data
->mode
;
735 sb
.stat
.st_uid
= data
->uid
;
736 sb
.stat
.st_gid
= data
->gid
;
737 sb
.atime
= data
->atime
;
738 sb
.mtime
= data
->mtime
;
739 set_stat (data
->file_name
, &sb
,
740 -1, current_mode
, current_mode_mask
,
741 DIRTYPE
, data
->interdir
, data
->atflag
);
744 delayed_set_stat_head
= data
->next
;
751 /* Extractor functions for various member types */
754 extract_dir (char *file_name
, int typeflag
)
758 mode_t current_mode
= 0;
759 mode_t current_mode_mask
= 0;
761 bool interdir_made
= false;
763 /* Save 'root device' to avoid purging mount points. */
764 if (one_file_system_option
&& root_device
== 0)
768 if (fstatat (chdir_fd
, ".", &st
, 0) != 0)
771 root_device
= st
.st_dev
;
774 if (incremental_option
)
775 /* Read the entry and delete files that aren't listed in the archive. */
776 purge_directory (file_name
);
777 else if (typeflag
== GNUTYPE_DUMPDIR
)
780 /* If ownership or permissions will be restored later, create the
781 directory with restrictive permissions at first, so that in the
782 meantime processes owned by other users do not inadvertently
783 create files under this directory that inherit the wrong owner,
784 group, or permissions from the directory. If not root, though,
785 make the directory writeable and searchable at first, so that
786 files can be created under it. */
787 mode
= ((current_stat_info
.stat
.st_mode
788 & (0 < same_owner_option
|| 0 < same_permissions_option
791 | (we_are_root
? 0 : MODE_WXUSR
));
795 status
= mkdirat (chdir_fd
, file_name
, mode
);
798 current_mode
= mode
& ~ current_umask
;
799 current_mode_mask
= MODE_RWX
;
800 atflag
= AT_SYMLINK_NOFOLLOW
;
806 || old_files_option
== DEFAULT_OLD_FILES
807 || old_files_option
== OVERWRITE_OLD_FILES
))
810 if (deref_stat (file_name
, &st
) == 0)
812 current_mode
= st
.st_mode
;
813 current_mode_mask
= ALL_MODE_BITS
;
815 if (S_ISDIR (current_mode
))
819 repair_delayed_set_stat (file_name
, &st
);
828 switch (maybe_recoverable (file_name
, false, &interdir_made
))
839 mkdir_error (file_name
);
848 || old_files_option
== DEFAULT_OLD_FILES
849 || old_files_option
== OVERWRITE_OLD_FILES
)
850 delay_set_stat (file_name
, ¤t_stat_info
,
851 current_mode
, current_mode_mask
,
852 current_stat_info
.stat
.st_mode
, atflag
);
859 open_output_file (char const *file_name
, int typeflag
, mode_t mode
,
860 mode_t
*current_mode
, mode_t
*current_mode_mask
)
863 bool overwriting_old_files
= old_files_option
== OVERWRITE_OLD_FILES
;
864 int openflag
= (O_WRONLY
| O_BINARY
| O_CLOEXEC
| O_NOCTTY
| O_NONBLOCK
866 | (overwriting_old_files
867 ? O_TRUNC
| (dereference_option
? 0 : O_NOFOLLOW
)
870 if (typeflag
== CONTTYPE
)
872 static int conttype_diagnosed
;
874 if (!conttype_diagnosed
)
876 conttype_diagnosed
= 1;
877 WARNOPT (WARN_CONTIGUOUS_CAST
,
878 (0, 0, _("Extracting contiguous files as regular files")));
882 /* If O_NOFOLLOW is needed but does not work, check for a symlink
883 separately. There's a race condition, but that cannot be avoided
884 on hosts lacking O_NOFOLLOW. */
885 if (! O_NOFOLLOW
&& overwriting_old_files
&& ! dereference_option
)
888 if (fstatat (chdir_fd
, file_name
, &st
, AT_SYMLINK_NOFOLLOW
) == 0
889 && S_ISLNK (st
.st_mode
))
896 fd
= openat (chdir_fd
, file_name
, openflag
, mode
);
899 if (overwriting_old_files
)
902 if (fstat (fd
, &st
) != 0)
909 if (! S_ISREG (st
.st_mode
))
915 *current_mode
= st
.st_mode
;
916 *current_mode_mask
= ALL_MODE_BITS
;
920 *current_mode
= mode
& ~ current_umask
;
921 *current_mode_mask
= MODE_RWX
;
929 extract_file (char *file_name
, int typeflag
)
933 union block
*data_block
;
937 bool interdir_made
= false;
938 mode_t mode
= (current_stat_info
.stat
.st_mode
& MODE_RWX
939 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
940 mode_t current_mode
= 0;
941 mode_t current_mode_mask
= 0;
943 if (to_stdout_option
)
945 else if (to_command_option
)
947 fd
= sys_exec_command (file_name
, 'f', ¤t_stat_info
);
956 while ((fd
= open_output_file (file_name
, typeflag
, mode
,
957 ¤t_mode
, ¤t_mode_mask
))
960 int recover
= maybe_recoverable (file_name
, true, &interdir_made
);
961 if (recover
!= RECOVER_OK
)
964 if (recover
== RECOVER_SKIP
)
966 open_error (file_name
);
972 mv_begin_read (¤t_stat_info
);
973 if (current_stat_info
.is_sparse
)
974 sparse_extract_file (fd
, ¤t_stat_info
, &size
);
976 for (size
= current_stat_info
.stat
.st_size
; size
> 0; )
980 /* Locate data, determine max length writeable, write it,
981 block that we have used the data, then check if the write
984 data_block
= find_next_block ();
987 ERROR ((0, 0, _("Unexpected EOF in archive")));
988 break; /* FIXME: What happens, then? */
991 written
= available_space_after (data_block
);
996 count
= full_write (fd
, data_block
->buffer
, written
);
999 set_next_block_after ((union block
*)
1000 (data_block
->buffer
+ written
- 1));
1001 if (count
!= written
)
1003 if (!to_command_option
)
1004 write_error_details (file_name
, count
, written
);
1005 /* FIXME: shouldn't we restore from backup? */
1014 /* If writing to stdout, don't try to do anything to the filename;
1015 it doesn't exist, or we don't want to touch it anyway. */
1017 if (to_stdout_option
)
1020 if (! to_command_option
)
1021 set_stat (file_name
, ¤t_stat_info
, fd
,
1022 current_mode
, current_mode_mask
, typeflag
, false,
1023 (old_files_option
== OVERWRITE_OLD_FILES
1024 ? 0 : AT_SYMLINK_NOFOLLOW
));
1026 status
= close (fd
);
1028 close_error (file_name
);
1030 if (to_command_option
)
1031 sys_wait_command ();
1036 /* Create a placeholder file with name FILE_NAME, which will be
1037 replaced after other extraction is done by a symbolic link if
1038 IS_SYMLINK is true, and by a hard link otherwise. Set
1039 *INTERDIR_MADE if an intermediate directory is made in the
1043 create_placeholder_file (char *file_name
, bool is_symlink
, bool *interdir_made
)
1048 while ((fd
= openat (chdir_fd
, file_name
, O_WRONLY
| O_CREAT
| O_EXCL
, 0)) < 0)
1050 switch (maybe_recoverable (file_name
, false, interdir_made
))
1059 open_error (file_name
);
1064 if (fstat (fd
, &st
) != 0)
1066 stat_error (file_name
);
1069 else if (close (fd
) != 0)
1070 close_error (file_name
);
1073 struct delayed_set_stat
*h
;
1074 struct delayed_link
*p
=
1075 xmalloc (offsetof (struct delayed_link
, target
)
1076 + strlen (current_stat_info
.link_name
)
1078 p
->next
= delayed_link_head
;
1079 delayed_link_head
= p
;
1082 p
->birthtime
= get_stat_birthtime (&st
);
1083 p
->is_symlink
= is_symlink
;
1086 p
->mode
= current_stat_info
.stat
.st_mode
;
1087 p
->uid
= current_stat_info
.stat
.st_uid
;
1088 p
->gid
= current_stat_info
.stat
.st_gid
;
1089 p
->atime
= current_stat_info
.atime
;
1090 p
->mtime
= current_stat_info
.mtime
;
1092 p
->change_dir
= chdir_current
;
1093 p
->sources
= xmalloc (offsetof (struct string_list
, string
)
1094 + strlen (file_name
) + 1);
1095 p
->sources
->next
= 0;
1096 strcpy (p
->sources
->string
, file_name
);
1097 strcpy (p
->target
, current_stat_info
.link_name
);
1099 h
= delayed_set_stat_head
;
1100 if (h
&& ! h
->after_links
1101 && strncmp (file_name
, h
->file_name
, h
->file_name_len
) == 0
1102 && ISSLASH (file_name
[h
->file_name_len
])
1103 && (last_component (file_name
) == file_name
+ h
->file_name_len
+ 1))
1104 mark_after_links (h
);
1113 extract_link (char *file_name
, int typeflag
)
1115 bool interdir_made
= false;
1116 char const *link_name
;
1119 link_name
= current_stat_info
.link_name
;
1121 if (! absolute_names_option
&& contains_dot_dot (link_name
))
1122 return create_placeholder_file (file_name
, false, &interdir_made
);
1126 struct stat st1
, st2
;
1128 int status
= linkat (chdir_fd
, link_name
, chdir_fd
, file_name
, 0);
1133 struct delayed_link
*ds
= delayed_link_head
;
1135 && fstatat (chdir_fd
, link_name
, &st1
, AT_SYMLINK_NOFOLLOW
) == 0)
1136 for (; ds
; ds
= ds
->next
)
1137 if (ds
->change_dir
== chdir_current
1138 && ds
->dev
== st1
.st_dev
1139 && ds
->ino
== st1
.st_ino
1140 && (timespec_cmp (ds
->birthtime
, get_stat_birthtime (&st1
))
1143 struct string_list
*p
= xmalloc (offsetof (struct string_list
, string
)
1144 + strlen (file_name
) + 1);
1145 strcpy (p
->string
, file_name
);
1146 p
->next
= ds
->sources
;
1152 else if ((e
== EEXIST
&& strcmp (link_name
, file_name
) == 0)
1153 || ((fstatat (chdir_fd
, link_name
, &st1
, AT_SYMLINK_NOFOLLOW
)
1155 && (fstatat (chdir_fd
, file_name
, &st2
, AT_SYMLINK_NOFOLLOW
)
1157 && st1
.st_dev
== st2
.st_dev
1158 && st1
.st_ino
== st2
.st_ino
))
1163 while ((rc
= maybe_recoverable (file_name
, false, &interdir_made
))
1166 if (rc
== RECOVER_SKIP
)
1168 if (!(incremental_option
&& errno
== EEXIST
))
1170 link_error (link_name
, file_name
);
1177 extract_symlink (char *file_name
, int typeflag
)
1180 bool interdir_made
= false;
1182 if (! absolute_names_option
1183 && (IS_ABSOLUTE_FILE_NAME (current_stat_info
.link_name
)
1184 || contains_dot_dot (current_stat_info
.link_name
)))
1185 return create_placeholder_file (file_name
, true, &interdir_made
);
1187 while (symlinkat (current_stat_info
.link_name
, chdir_fd
, file_name
) != 0)
1188 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1197 symlink_error (current_stat_info
.link_name
, file_name
);
1201 set_stat (file_name
, ¤t_stat_info
, -1, 0, 0,
1202 SYMTYPE
, false, AT_SYMLINK_NOFOLLOW
);
1206 static int warned_once
;
1211 WARNOPT (WARN_SYMBOLIC_CAST
,
1213 _("Attempting extraction of symbolic links as hard links")));
1215 return extract_link (file_name
, typeflag
);
1219 #if S_IFCHR || S_IFBLK
1221 extract_node (char *file_name
, int typeflag
)
1223 bool interdir_made
= false;
1224 mode_t mode
= (current_stat_info
.stat
.st_mode
& (MODE_RWX
| S_IFBLK
| S_IFCHR
)
1225 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
1227 while (mknodat (chdir_fd
, file_name
, mode
, current_stat_info
.stat
.st_rdev
)
1229 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1238 mknod_error (file_name
);
1242 set_stat (file_name
, ¤t_stat_info
, -1,
1243 mode
& ~ current_umask
, MODE_RWX
,
1244 typeflag
, false, AT_SYMLINK_NOFOLLOW
);
1249 #if HAVE_MKFIFO || defined mkfifo
1251 extract_fifo (char *file_name
, int typeflag
)
1253 bool interdir_made
= false;
1254 mode_t mode
= (current_stat_info
.stat
.st_mode
& MODE_RWX
1255 & ~ (0 < same_owner_option
? S_IRWXG
| S_IRWXO
: 0));
1257 while (mkfifoat (chdir_fd
, file_name
, mode
) != 0)
1258 switch (maybe_recoverable (file_name
, false, &interdir_made
))
1267 mkfifo_error (file_name
);
1271 set_stat (file_name
, ¤t_stat_info
, -1,
1272 mode
& ~ current_umask
, MODE_RWX
,
1273 typeflag
, false, AT_SYMLINK_NOFOLLOW
);
1279 extract_volhdr (char *file_name
, int typeflag
)
1286 extract_failure (char *file_name
, int typeflag
)
1291 typedef int (*tar_extractor_t
) (char *file_name
, int typeflag
);
1295 /* Prepare to extract a file. Find extractor function.
1296 Return zero if extraction should not proceed. */
1299 prepare_to_extract (char const *file_name
, int typeflag
, tar_extractor_t
*fun
)
1303 if (EXTRACT_OVER_PIPE
)
1306 /* Select the extractor */
1309 case GNUTYPE_SPARSE
:
1310 *fun
= extract_file
;
1317 /* Appears to be a file. But BSD tar uses the convention that a slash
1318 suffix means a directory. */
1319 if (current_stat_info
.had_trailing_slash
)
1323 *fun
= extract_file
;
1329 *fun
= extract_symlink
;
1333 *fun
= extract_link
;
1338 current_stat_info
.stat
.st_mode
|= S_IFCHR
;
1339 *fun
= extract_node
;
1345 current_stat_info
.stat
.st_mode
|= S_IFBLK
;
1346 *fun
= extract_node
;
1350 #if HAVE_MKFIFO || defined mkfifo
1352 *fun
= extract_fifo
;
1357 case GNUTYPE_DUMPDIR
:
1359 if (current_stat_info
.is_dumpdir
)
1360 delay_directory_restore_option
= true;
1363 case GNUTYPE_VOLHDR
:
1364 *fun
= extract_volhdr
;
1367 case GNUTYPE_MULTIVOL
:
1369 _("%s: Cannot extract -- file is continued from another volume"),
1370 quotearg_colon (current_stat_info
.file_name
)));
1371 *fun
= extract_failure
;
1374 case GNUTYPE_LONGNAME
:
1375 case GNUTYPE_LONGLINK
:
1376 ERROR ((0, 0, _("Unexpected long name header")));
1377 *fun
= extract_failure
;
1381 WARNOPT (WARN_UNKNOWN_CAST
,
1383 _("%s: Unknown file type `%c', extracted as normal file"),
1384 quotearg_colon (file_name
), typeflag
));
1385 *fun
= extract_file
;
1388 /* Determine whether the extraction should proceed */
1392 switch (old_files_option
)
1394 case UNLINK_FIRST_OLD_FILES
:
1395 if (!remove_any_file (file_name
,
1396 recursive_unlink_option
? RECURSIVE_REMOVE_OPTION
1397 : ORDINARY_REMOVE_OPTION
)
1398 && errno
&& errno
!= ENOENT
)
1400 unlink_error (file_name
);
1405 case KEEP_NEWER_FILES
:
1406 if (file_newer_p (file_name
, 0, ¤t_stat_info
))
1408 WARNOPT (WARN_IGNORE_NEWER
,
1409 (0, 0, _("Current %s is newer or same age"),
1410 quote (file_name
)));
1422 /* Extract a file from the archive. */
1424 extract_archive (void)
1427 tar_extractor_t fun
;
1429 fatal_exit_hook
= extract_finish
;
1431 set_next_block_after (current_header
);
1433 if (!current_stat_info
.file_name
[0]
1434 || (interactive_option
1435 && !confirm ("extract", current_stat_info
.file_name
)))
1441 /* Print the block from current_header and current_stat. */
1443 print_header (¤t_stat_info
, current_header
, -1);
1445 /* Restore stats for all non-ancestor directories, unless
1446 it is an incremental archive.
1447 (see NOTICE in the comment to delay_set_stat above) */
1448 if (!delay_directory_restore_option
)
1450 int dir
= chdir_current
;
1451 apply_nonancestor_delayed_set_stat (current_stat_info
.file_name
, 0);
1455 /* Take a safety backup of a previously existing file. */
1458 if (!maybe_backup_file (current_stat_info
.file_name
, 0))
1461 ERROR ((0, e
, _("%s: Was unable to backup this file"),
1462 quotearg_colon (current_stat_info
.file_name
)));
1467 /* Extract the archive entry according to its type. */
1469 typeflag
= sparse_member_p (¤t_stat_info
) ?
1470 GNUTYPE_SPARSE
: current_header
->header
.typeflag
;
1472 if (prepare_to_extract (current_stat_info
.file_name
, typeflag
, &fun
))
1474 if (fun
&& (*fun
) (current_stat_info
.file_name
, typeflag
)
1476 undo_last_backup ();
1483 /* Extract the links whose final extraction were delayed. */
1485 apply_delayed_links (void)
1487 struct delayed_link
*ds
;
1489 for (ds
= delayed_link_head
; ds
; )
1491 struct string_list
*sources
= ds
->sources
;
1492 char const *valid_source
= 0;
1494 chdir_do (ds
->change_dir
);
1496 for (sources
= ds
->sources
; sources
; sources
= sources
->next
)
1498 char const *source
= sources
->string
;
1501 /* Make sure the placeholder file is still there. If not,
1502 don't create a link, as the placeholder was probably
1503 removed by a later extraction. */
1504 if (fstatat (chdir_fd
, source
, &st
, AT_SYMLINK_NOFOLLOW
) == 0
1505 && st
.st_dev
== ds
->dev
1506 && st
.st_ino
== ds
->ino
1507 && timespec_cmp (get_stat_birthtime (&st
), ds
->birthtime
) == 0)
1509 /* Unlink the placeholder, then create a hard link if possible,
1510 a symbolic link otherwise. */
1511 if (unlinkat (chdir_fd
, source
, 0) != 0)
1512 unlink_error (source
);
1513 else if (valid_source
1514 && (linkat (chdir_fd
, valid_source
, chdir_fd
, source
, 0)
1517 else if (!ds
->is_symlink
)
1519 if (linkat (chdir_fd
, ds
->target
, chdir_fd
, source
, 0) != 0)
1520 link_error (ds
->target
, source
);
1522 else if (symlinkat (ds
->target
, chdir_fd
, source
) != 0)
1523 symlink_error (ds
->target
, source
);
1526 struct tar_stat_info st1
;
1527 st1
.stat
.st_mode
= ds
->mode
;
1528 st1
.stat
.st_uid
= ds
->uid
;
1529 st1
.stat
.st_gid
= ds
->gid
;
1530 st1
.atime
= ds
->atime
;
1531 st1
.mtime
= ds
->mtime
;
1532 set_stat (source
, &st1
, -1, 0, 0, SYMTYPE
,
1533 false, AT_SYMLINK_NOFOLLOW
);
1534 valid_source
= source
;
1539 for (sources
= ds
->sources
; sources
; )
1541 struct string_list
*next
= sources
->next
;
1547 struct delayed_link
*next
= ds
->next
;
1553 delayed_link_head
= 0;
1556 /* Finish the extraction of an archive. */
1558 extract_finish (void)
1560 /* First, fix the status of ordinary directories that need fixing. */
1561 apply_nonancestor_delayed_set_stat ("", 0);
1563 /* Then, apply delayed links, so that they don't affect delayed
1564 directory status-setting for ordinary directories. */
1565 apply_delayed_links ();
1567 /* Finally, fix the status of directories that are ancestors
1568 of delayed links. */
1569 apply_nonancestor_delayed_set_stat ("", 1);
1573 rename_directory (char *src
, char *dst
)
1575 if (renameat (chdir_fd
, src
, chdir_fd
, dst
) != 0)
1583 if (make_directories (dst
, &interdir_made
) == 0)
1585 if (renameat (chdir_fd
, src
, chdir_fd
, dst
) == 0)
1592 /* FIXME: Fall back to recursive copying */
1598 ERROR ((0, e
, _("Cannot rename %s to %s"),