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 ctime of the placeholder. Use
114 ctime, not mtime, to make false matches less likely if some
115 other process removes the placeholder. */
118 struct timespec ctime;
120 /* True if the link is symbolic. */
123 /* The desired metadata, valid only the link is symbolic. */
127 struct timespec atime;
128 struct timespec mtime;
130 /* The directory that the sources and target are relative to. */
133 /* A list of sources for this link. The sources are all to be
134 hard-linked together. */
135 struct string_list *sources;
137 /* The desired target of the desired link. */
141 static struct delayed_link *delayed_link_head;
145 struct string_list *next;
149 /* Set up to extract files. */
153 we_are_root = geteuid () == 0;
154 same_permissions_option += we_are_root;
155 same_owner_option += we_are_root;
157 /* Option -p clears the kernel umask, so it does not affect proper
158 restoration of file permissions. New intermediate directories will
159 comply with umask at start of program. */
161 newdir_umask = umask (0);
162 if (0 < same_permissions_option)
166 umask (newdir_umask); /* restore the kernel umask */
167 current_umask = newdir_umask;
171 /* Use fchmod if possible, fchmodat otherwise. */
173 fd_chmod (int fd, char const *file, mode_t mode, int atflag)
177 int result = fchmod (fd, mode);
178 if (result == 0 || implemented (errno))
181 return fchmodat (chdir_fd, file, mode, atflag);
184 /* Use fchown if possible, fchownat otherwise. */
186 fd_chown (int fd, char const *file, uid_t uid, gid_t gid, int atflag)
190 int result = fchown (fd, uid, gid);
191 if (result == 0 || implemented (errno))
194 return fchownat (chdir_fd, file, uid, gid, atflag);
197 /* Use fstat if possible, fstatat otherwise. */
199 fd_stat (int fd, char const *file, struct stat *st, int atflag)
203 : fstatat (chdir_fd, file, st, atflag));
206 /* Set the mode for FILE_NAME to MODE.
207 MODE_MASK specifies the bits of MODE that we care about;
208 thus if MODE_MASK is zero, do nothing.
209 If FD is nonnegative, it is a file descriptor for the file.
210 CURRENT_MODE and CURRENT_MODE_MASK specify information known about
211 the file's current mode, using the style of struct delayed_set_stat.
212 TYPEFLAG specifies the type of the file.
213 ATFLAG specifies the flag to use when statting the file. */
215 set_mode (char const *file_name,
216 mode_t mode, mode_t mode_mask, int fd,
217 mode_t current_mode, mode_t current_mode_mask,
218 char typeflag, int atflag)
220 if (((current_mode ^ mode) | ~ current_mode_mask) & mode_mask)
222 if (MODE_ALL & ~ mode_mask & ~ current_mode_mask)
225 if (fd_stat (fd, file_name, &st, atflag) != 0)
227 stat_error (file_name);
230 current_mode = st.st_mode;
233 current_mode &= MODE_ALL;
234 mode = (current_mode & ~ mode_mask) | (mode & mode_mask);
236 if (current_mode != mode)
239 fd_chmod (fd, file_name, mode, atflag) == 0 ? 0 : errno;
241 /* On Solaris, chmod may fail if we don't have PRIV_ALL, because
242 setuid-root files would otherwise be a backdoor. See
243 http://opensolaris.org/jive/thread.jspa?threadID=95826
245 if (chmod_errno == EPERM && (mode & S_ISUID)
246 && priv_set_restore_linkdir () == 0)
249 fd_chmod (fd, file_name, mode, atflag) == 0 ? 0 : errno;
250 priv_set_remove_linkdir ();
253 /* Linux fchmodat does not support AT_SYMLINK_NOFOLLOW, and
254 returns ENOTSUP even when operating on non-symlinks, try
255 again with the flag disabled if it does not appear to be
256 supported and if the file is not a symlink. This
257 introduces a race, alas. */
258 if (atflag && typeflag != SYMTYPE && ! implemented (chmod_errno))
259 chmod_errno = fd_chmod (fd, file_name, mode, 0) == 0 ? 0 : errno;
262 && (typeflag != SYMTYPE || implemented (chmod_errno)))
265 chmod_error_details (file_name, mode);
271 /* Check time after successfully setting FILE_NAME's time stamp to T. */
273 check_time (char const *file_name, struct timespec t)
276 WARNOPT (WARN_TIMESTAMP,
277 (0, 0, _("%s: implausibly old time stamp %s"),
278 file_name, tartime (t, true)));
279 else if (timespec_cmp (volume_start_time, t) < 0)
283 if (timespec_cmp (now, t) < 0)
285 char buf[TIMESPEC_STRSIZE_BOUND];
286 struct timespec diff;
287 diff.tv_sec = t.tv_sec - now.tv_sec;
288 diff.tv_nsec = t.tv_nsec - now.tv_nsec;
289 if (diff.tv_nsec < 0)
291 diff.tv_nsec += BILLION;
294 WARNOPT (WARN_TIMESTAMP,
295 (0, 0, _("%s: time stamp %s is %s s in the future"),
296 file_name, tartime (t, true), code_timespec (diff, buf)));
301 /* Restore stat attributes (owner, group, mode and times) for
302 FILE_NAME, using information given in *ST.
303 If FD is nonnegative, it is a file descriptor for the file.
304 CURRENT_MODE and CURRENT_MODE_MASK specify information known about
305 the file's current mode, using the style of struct delayed_set_stat.
306 TYPEFLAG specifies the type of the file.
307 If INTERDIR, this is an intermediate directory.
308 ATFLAG specifies the flag to use when statting the file. */
311 set_stat (char const *file_name,
312 struct tar_stat_info const *st,
313 int fd, mode_t current_mode, mode_t current_mode_mask,
314 char typeflag, bool interdir, int atflag)
316 /* Do the utime before the chmod because some versions of utime are
317 broken and trash the modes of the file. */
319 if (! touch_option && ! interdir)
321 struct timespec ts[2];
322 if (incremental_option)
325 ts[0].tv_nsec = UTIME_OMIT;
328 if (fdutimensat (fd, chdir_fd, file_name, ts, atflag) == 0)
330 if (incremental_option)
331 check_time (file_name, ts[0]);
332 check_time (file_name, ts[1]);
334 else if (typeflag != SYMTYPE || implemented (errno))
335 utime_error (file_name);
338 if (0 < same_owner_option && ! interdir)
340 /* Some systems allow non-root users to give files away. Once this
341 done, it is not possible anymore to change file permissions.
342 However, setting file permissions now would be incorrect, since
343 they would apply to the wrong user, and there would be a race
344 condition. So, don't use systems that allow non-root users to
346 uid_t uid = st->stat.st_uid;
347 gid_t gid = st->stat.st_gid;
349 if (fd_chown (fd, file_name, uid, gid, atflag) == 0)
351 /* Changing the owner can clear st_mode bits in some cases. */
352 if ((current_mode | ~ current_mode_mask) & S_IXUGO)
353 current_mode_mask &= ~ (current_mode & (S_ISUID | S_ISGID));
355 else if (typeflag != SYMTYPE || implemented (errno))
356 chown_error_details (file_name, uid, gid);
360 st->stat.st_mode & ~ current_umask,
361 0 < same_permissions_option && ! interdir ? MODE_ALL : MODE_RWX,
362 fd, current_mode, current_mode_mask, typeflag, atflag);
365 /* For each entry H in the leading prefix of entries in HEAD that do
366 not have after_links marked, mark H and fill in its dev and ino
367 members. Assume HEAD && ! HEAD->after_links. */
369 mark_after_links (struct delayed_set_stat *head)
371 struct delayed_set_stat *h = head;
378 if (deref_stat (h->file_name, &st) != 0)
379 stat_error (h->file_name);
386 while ((h = h->next) && ! h->after_links);
389 /* Remember to restore stat attributes (owner, group, mode and times)
390 for the directory FILE_NAME, using information given in *ST,
391 once we stop extracting files into that directory.
393 If ST is null, merely create a placeholder node for an intermediate
394 directory that was created by make_directories.
396 NOTICE: this works only if the archive has usual member order, i.e.
397 directory, then the files in that directory. Incremental archive have
398 somewhat reversed order: first go subdirectories, then all other
399 members. To help cope with this case the variable
400 delay_directory_restore_option is set by prepare_to_extract.
402 If an archive was explicitely created so that its member order is
403 reversed, some directory timestamps can be restored incorrectly,
405 tar --no-recursion -cf archive dir dir/file1 foo dir/file2
408 delay_set_stat (char const *file_name, struct tar_stat_info const *st,
409 mode_t current_mode, mode_t current_mode_mask,
410 mode_t mode, int atflag)
412 size_t file_name_len = strlen (file_name);
413 struct delayed_set_stat *data =
414 xmalloc (offsetof (struct delayed_set_stat, file_name)
415 + file_name_len + 1);
416 data->next = delayed_set_stat_head;
420 data->dev = st->stat.st_dev;
421 data->ino = st->stat.st_ino;
422 data->uid = st->stat.st_uid;
423 data->gid = st->stat.st_gid;
424 data->atime = st->atime;
425 data->mtime = st->mtime;
427 data->file_name_len = file_name_len;
428 data->current_mode = current_mode;
429 data->current_mode_mask = current_mode_mask;
430 data->interdir = ! st;
431 data->atflag = atflag;
432 data->after_links = 0;
433 data->change_dir = chdir_current;
434 strcpy (data->file_name, file_name);
435 delayed_set_stat_head = data;
436 if (must_be_dot_or_slash (file_name))
437 mark_after_links (data);
440 /* Update the delayed_set_stat info for an intermediate directory
441 created within the file name of DIR. The intermediate directory turned
442 out to be the same as this directory, e.g. due to ".." or symbolic
443 links. *DIR_STAT_INFO is the status of the directory. */
445 repair_delayed_set_stat (char const *dir,
446 struct stat const *dir_stat_info)
448 struct delayed_set_stat *data;
449 for (data = delayed_set_stat_head; data; data = data->next)
452 if (fstatat (chdir_fd, data->file_name, &st, data->atflag) != 0)
454 stat_error (data->file_name);
458 if (st.st_dev == dir_stat_info->st_dev
459 && st.st_ino == dir_stat_info->st_ino)
461 data->dev = current_stat_info.stat.st_dev;
462 data->ino = current_stat_info.stat.st_ino;
463 data->mode = current_stat_info.stat.st_mode;
464 data->uid = current_stat_info.stat.st_uid;
465 data->gid = current_stat_info.stat.st_gid;
466 data->atime = current_stat_info.atime;
467 data->mtime = current_stat_info.mtime;
468 data->current_mode = st.st_mode;
469 data->current_mode_mask = ALL_MODE_BITS;
470 data->interdir = false;
475 ERROR ((0, 0, _("%s: Unexpected inconsistency when making directory"),
476 quotearg_colon (dir)));
479 /* After a file/link/directory creation has failed, see if
480 it's because some required directory was not present, and if so,
481 create all required directories. Return zero if all the required
482 directories were created, nonzero (issuing a diagnostic) otherwise.
483 Set *INTERDIR_MADE if at least one directory was created. */
485 make_directories (char *file_name, bool *interdir_made)
487 char *cursor0 = file_name + FILE_SYSTEM_PREFIX_LEN (file_name);
488 char *cursor; /* points into the file name */
490 for (cursor = cursor0; *cursor; cursor++)
496 if (! ISSLASH (*cursor))
499 /* Avoid mkdir of empty string, if leading or double '/'. */
501 if (cursor == cursor0 || ISSLASH (cursor[-1]))
504 /* Avoid mkdir where last part of file name is "." or "..". */
506 if (cursor[-1] == '.'
507 && (cursor == cursor0 + 1 || ISSLASH (cursor[-2])
508 || (cursor[-2] == '.'
509 && (cursor == cursor0 + 2 || ISSLASH (cursor[-3])))))
512 *cursor = '\0'; /* truncate the name there */
513 desired_mode = MODE_RWX & ~ newdir_umask;
514 mode = desired_mode | (we_are_root ? 0 : MODE_WXUSR);
515 status = mkdirat (chdir_fd, file_name, mode);
519 /* Create a struct delayed_set_stat even if
520 mode == desired_mode, because
521 repair_delayed_set_stat may need to update the struct. */
522 delay_set_stat (file_name,
523 0, mode & ~ current_umask, MODE_RWX,
524 desired_mode, AT_SYMLINK_NOFOLLOW);
526 print_for_mkdir (file_name, cursor - file_name, desired_mode);
527 *interdir_made = true;
529 else if (errno == EEXIST)
533 /* Check whether the desired file exists. Even when the
534 file exists, mkdir can fail with some errno value E other
535 than EEXIST, so long as E describes an error condition
536 that also applies. */
539 status = fstatat (chdir_fd, file_name, &st, 0);
543 mkdir_error (file_name);
555 /* Return true if FILE_NAME (with status *STP, if STP) is not a
556 directory, and has a time stamp newer than (or equal to) that of
559 file_newer_p (const char *file_name, struct stat const *stp,
560 struct tar_stat_info *tar_stat)
566 if (deref_stat (file_name, &st) != 0)
570 stat_warn (file_name);
571 /* Be safer: if the file exists, assume it is newer. */
579 return (! S_ISDIR (stp->st_mode)
580 && tar_timespec_cmp (tar_stat->mtime, get_stat_mtime (stp)) <= 0);
585 #define RECOVER_SKIP 2
587 /* Attempt repairing what went wrong with the extraction. Delete an
588 already existing file or create missing intermediate directories.
589 Return RECOVER_OK if we somewhat increased our chances at a successful
590 extraction, RECOVER_NO if there are no chances, and RECOVER_SKIP if the
591 caller should skip extraction of that member. The value of errno is
592 properly restored on returning RECOVER_NO.
594 If REGULAR, the caller was trying to extract onto a regular file.
596 Set *INTERDIR_MADE if an intermediate directory is made as part of
597 the recovery process. */
600 maybe_recoverable (char *file_name, bool regular, bool *interdir_made)
604 struct stat const *stp = 0;
613 || old_files_option != OVERWRITE_OLD_FILES || dereference_option)
615 if (strchr (file_name, '/'))
617 if (deref_stat (file_name, &st) != 0)
622 /* The caller tried to open a symbolic link with O_NOFOLLOW.
623 Fall through, treating it as an already-existing file. */
626 /* Remove an old file, if the options allow this. */
628 switch (old_files_option)
633 case KEEP_NEWER_FILES:
634 if (file_newer_p (file_name, stp, ¤t_stat_info))
638 case DEFAULT_OLD_FILES:
639 case NO_OVERWRITE_DIR_OLD_FILES:
640 case OVERWRITE_OLD_FILES:
641 if (0 < remove_any_file (file_name, ORDINARY_REMOVE_OPTION))
645 case UNLINK_FIRST_OLD_FILES:
650 /* Attempt creating missing intermediate directories. */
651 if (make_directories (file_name, interdir_made) == 0 && *interdir_made)
656 /* Just say we can't do anything about it... */
664 /* Fix the statuses of all directories whose statuses need fixing, and
665 which are not ancestors of FILE_NAME. If AFTER_LINKS is
666 nonzero, do this for all such directories; otherwise, stop at the
667 first directory that is marked to be fixed up only after delayed
668 links are applied. */
670 apply_nonancestor_delayed_set_stat (char const *file_name, bool after_links)
672 size_t file_name_len = strlen (file_name);
673 bool check_for_renamed_directories = 0;
675 while (delayed_set_stat_head)
677 struct delayed_set_stat *data = delayed_set_stat_head;
678 bool skip_this_one = 0;
680 mode_t current_mode = data->current_mode;
681 mode_t current_mode_mask = data->current_mode_mask;
683 check_for_renamed_directories |= data->after_links;
685 if (after_links < data->after_links
686 || (data->file_name_len < file_name_len
687 && file_name[data->file_name_len]
688 && (ISSLASH (file_name[data->file_name_len])
689 || ISSLASH (file_name[data->file_name_len - 1]))
690 && memcmp (file_name, data->file_name, data->file_name_len) == 0))
693 chdir_do (data->change_dir);
695 if (check_for_renamed_directories)
697 if (fstatat (chdir_fd, data->file_name, &st, data->atflag) != 0)
699 stat_error (data->file_name);
704 current_mode = st.st_mode;
705 current_mode_mask = ALL_MODE_BITS;
706 if (! (st.st_dev == data->dev && st.st_ino == data->ino))
709 _("%s: Directory renamed before its status could be extracted"),
710 quotearg_colon (data->file_name)));
718 struct tar_stat_info sb;
719 sb.stat.st_mode = data->mode;
720 sb.stat.st_uid = data->uid;
721 sb.stat.st_gid = data->gid;
722 sb.atime = data->atime;
723 sb.mtime = data->mtime;
724 set_stat (data->file_name, &sb,
725 -1, current_mode, current_mode_mask,
726 DIRTYPE, data->interdir, data->atflag);
729 delayed_set_stat_head = data->next;
736 /* Extractor functions for various member types */
739 extract_dir (char *file_name, int typeflag)
743 mode_t current_mode = 0;
744 mode_t current_mode_mask = 0;
746 bool interdir_made = false;
748 /* Save 'root device' to avoid purging mount points. */
749 if (one_file_system_option && root_device == 0)
753 if (fstatat (chdir_fd, ".", &st, 0) != 0)
756 root_device = st.st_dev;
759 if (incremental_option)
760 /* Read the entry and delete files that aren't listed in the archive. */
761 purge_directory (file_name);
762 else if (typeflag == GNUTYPE_DUMPDIR)
765 /* If ownership or permissions will be restored later, create the
766 directory with restrictive permissions at first, so that in the
767 meantime processes owned by other users do not inadvertently
768 create files under this directory that inherit the wrong owner,
769 group, or permissions from the directory. If not root, though,
770 make the directory writeable and searchable at first, so that
771 files can be created under it. */
772 mode = ((current_stat_info.stat.st_mode
773 & (0 < same_owner_option || 0 < same_permissions_option
776 | (we_are_root ? 0 : MODE_WXUSR));
780 status = mkdirat (chdir_fd, file_name, mode);
783 current_mode = mode & ~ current_umask;
784 current_mode_mask = MODE_RWX;
785 atflag = AT_SYMLINK_NOFOLLOW;
791 || old_files_option == DEFAULT_OLD_FILES
792 || old_files_option == OVERWRITE_OLD_FILES))
795 if (deref_stat (file_name, &st) == 0)
797 current_mode = st.st_mode;
798 current_mode_mask = ALL_MODE_BITS;
800 if (S_ISDIR (current_mode))
804 repair_delayed_set_stat (file_name, &st);
813 switch (maybe_recoverable (file_name, false, &interdir_made))
824 mkdir_error (file_name);
833 || old_files_option == DEFAULT_OLD_FILES
834 || old_files_option == OVERWRITE_OLD_FILES)
835 delay_set_stat (file_name, ¤t_stat_info,
836 current_mode, current_mode_mask,
837 current_stat_info.stat.st_mode, atflag);
844 open_output_file (char const *file_name, int typeflag, mode_t mode,
845 mode_t *current_mode, mode_t *current_mode_mask)
848 bool overwriting_old_files = old_files_option == OVERWRITE_OLD_FILES;
849 int openflag = (O_WRONLY | O_BINARY | O_CLOEXEC | O_NOCTTY | O_NONBLOCK
851 | (overwriting_old_files
852 ? O_TRUNC | (dereference_option ? 0 : O_NOFOLLOW)
855 if (typeflag == CONTTYPE)
857 static int conttype_diagnosed;
859 if (!conttype_diagnosed)
861 conttype_diagnosed = 1;
862 WARNOPT (WARN_CONTIGUOUS_CAST,
863 (0, 0, _("Extracting contiguous files as regular files")));
867 fd = openat (chdir_fd, file_name, openflag, mode);
870 if (overwriting_old_files)
873 if (fstat (fd, &st) != 0)
880 if (! S_ISREG (st.st_mode))
886 *current_mode = st.st_mode;
887 *current_mode_mask = ALL_MODE_BITS;
891 *current_mode = mode & ~ current_umask;
892 *current_mode_mask = MODE_RWX;
900 extract_file (char *file_name, int typeflag)
904 union block *data_block;
908 bool interdir_made = false;
909 mode_t mode = (current_stat_info.stat.st_mode & MODE_RWX
910 & ~ (0 < same_owner_option ? S_IRWXG | S_IRWXO : 0));
911 mode_t current_mode = 0;
912 mode_t current_mode_mask = 0;
914 if (to_stdout_option)
916 else if (to_command_option)
918 fd = sys_exec_command (file_name, 'f', ¤t_stat_info);
927 while ((fd = open_output_file (file_name, typeflag, mode,
928 ¤t_mode, ¤t_mode_mask))
931 int recover = maybe_recoverable (file_name, true, &interdir_made);
932 if (recover != RECOVER_OK)
935 if (recover == RECOVER_SKIP)
937 open_error (file_name);
943 mv_begin_read (¤t_stat_info);
944 if (current_stat_info.is_sparse)
945 sparse_extract_file (fd, ¤t_stat_info, &size);
947 for (size = current_stat_info.stat.st_size; size > 0; )
951 /* Locate data, determine max length writeable, write it,
952 block that we have used the data, then check if the write
955 data_block = find_next_block ();
958 ERROR ((0, 0, _("Unexpected EOF in archive")));
959 break; /* FIXME: What happens, then? */
962 written = available_space_after (data_block);
967 count = full_write (fd, data_block->buffer, written);
970 set_next_block_after ((union block *)
971 (data_block->buffer + written - 1));
972 if (count != written)
974 if (!to_command_option)
975 write_error_details (file_name, count, written);
976 /* FIXME: shouldn't we restore from backup? */
985 /* If writing to stdout, don't try to do anything to the filename;
986 it doesn't exist, or we don't want to touch it anyway. */
988 if (to_stdout_option)
991 if (! to_command_option)
992 set_stat (file_name, ¤t_stat_info, fd,
993 current_mode, current_mode_mask, typeflag, false,
994 (old_files_option == OVERWRITE_OLD_FILES
995 ? 0 : AT_SYMLINK_NOFOLLOW));
999 close_error (file_name);
1001 if (to_command_option)
1002 sys_wait_command ();
1007 /* Create a placeholder file with name FILE_NAME, which will be
1008 replaced after other extraction is done by a symbolic link if
1009 IS_SYMLINK is true, and by a hard link otherwise. Set
1010 *INTERDIR_MADE if an intermediate directory is made in the
1014 create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)
1019 while ((fd = openat (chdir_fd, file_name, O_WRONLY | O_CREAT | O_EXCL, 0)) < 0)
1021 switch (maybe_recoverable (file_name, false, interdir_made))
1030 open_error (file_name);
1035 if (fstat (fd, &st) != 0)
1037 stat_error (file_name);
1040 else if (close (fd) != 0)
1041 close_error (file_name);
1044 struct delayed_set_stat *h;
1045 struct delayed_link *p =
1046 xmalloc (offsetof (struct delayed_link, target)
1047 + strlen (current_stat_info.link_name)
1049 p->next = delayed_link_head;
1050 delayed_link_head = p;
1053 p->ctime = get_stat_ctime (&st);
1054 p->is_symlink = is_symlink;
1057 p->mode = current_stat_info.stat.st_mode;
1058 p->uid = current_stat_info.stat.st_uid;
1059 p->gid = current_stat_info.stat.st_gid;
1060 p->atime = current_stat_info.atime;
1061 p->mtime = current_stat_info.mtime;
1063 p->change_dir = chdir_current;
1064 p->sources = xmalloc (offsetof (struct string_list, string)
1065 + strlen (file_name) + 1);
1066 p->sources->next = 0;
1067 strcpy (p->sources->string, file_name);
1068 strcpy (p->target, current_stat_info.link_name);
1070 h = delayed_set_stat_head;
1071 if (h && ! h->after_links
1072 && strncmp (file_name, h->file_name, h->file_name_len) == 0
1073 && ISSLASH (file_name[h->file_name_len])
1074 && (last_component (file_name) == file_name + h->file_name_len + 1))
1075 mark_after_links (h);
1084 extract_link (char *file_name, int typeflag)
1086 bool interdir_made = false;
1087 char const *link_name;
1090 link_name = current_stat_info.link_name;
1092 if (! absolute_names_option && contains_dot_dot (link_name))
1093 return create_placeholder_file (file_name, false, &interdir_made);
1097 struct stat st1, st2;
1099 int status = linkat (chdir_fd, link_name, chdir_fd, file_name, 0);
1104 struct delayed_link *ds = delayed_link_head;
1106 && fstatat (chdir_fd, link_name, &st1, AT_SYMLINK_NOFOLLOW) == 0)
1107 for (; ds; ds = ds->next)
1108 if (ds->change_dir == chdir_current
1109 && ds->dev == st1.st_dev
1110 && ds->ino == st1.st_ino
1111 && timespec_cmp (ds->ctime, get_stat_ctime (&st1)) == 0)
1113 struct string_list *p = xmalloc (offsetof (struct string_list, string)
1114 + strlen (file_name) + 1);
1115 strcpy (p->string, file_name);
1116 p->next = ds->sources;
1122 else if ((e == EEXIST && strcmp (link_name, file_name) == 0)
1123 || ((fstatat (chdir_fd, link_name, &st1, AT_SYMLINK_NOFOLLOW)
1125 && (fstatat (chdir_fd, file_name, &st2, AT_SYMLINK_NOFOLLOW)
1127 && st1.st_dev == st2.st_dev
1128 && st1.st_ino == st2.st_ino))
1133 while ((rc = maybe_recoverable (file_name, false, &interdir_made))
1136 if (rc == RECOVER_SKIP)
1138 if (!(incremental_option && errno == EEXIST))
1140 link_error (link_name, file_name);
1147 extract_symlink (char *file_name, int typeflag)
1150 bool interdir_made = false;
1152 if (! absolute_names_option
1153 && (IS_ABSOLUTE_FILE_NAME (current_stat_info.link_name)
1154 || contains_dot_dot (current_stat_info.link_name)))
1155 return create_placeholder_file (file_name, true, &interdir_made);
1157 while (symlinkat (current_stat_info.link_name, chdir_fd, file_name) != 0)
1158 switch (maybe_recoverable (file_name, false, &interdir_made))
1167 symlink_error (current_stat_info.link_name, file_name);
1171 set_stat (file_name, ¤t_stat_info, -1, 0, 0,
1172 SYMTYPE, false, AT_SYMLINK_NOFOLLOW);
1176 static int warned_once;
1181 WARNOPT (WARN_SYMBOLIC_CAST,
1183 _("Attempting extraction of symbolic links as hard links")));
1185 return extract_link (file_name, typeflag);
1189 #if S_IFCHR || S_IFBLK
1191 extract_node (char *file_name, int typeflag)
1193 bool interdir_made = false;
1194 mode_t mode = (current_stat_info.stat.st_mode & (MODE_RWX | S_IFBLK | S_IFCHR)
1195 & ~ (0 < same_owner_option ? S_IRWXG | S_IRWXO : 0));
1197 while (mknodat (chdir_fd, file_name, mode, current_stat_info.stat.st_rdev)
1199 switch (maybe_recoverable (file_name, false, &interdir_made))
1208 mknod_error (file_name);
1212 set_stat (file_name, ¤t_stat_info, -1,
1213 mode & ~ current_umask, MODE_RWX,
1214 typeflag, false, AT_SYMLINK_NOFOLLOW);
1219 #if HAVE_MKFIFO || defined mkfifo
1221 extract_fifo (char *file_name, int typeflag)
1223 bool interdir_made = false;
1224 mode_t mode = (current_stat_info.stat.st_mode & MODE_RWX
1225 & ~ (0 < same_owner_option ? S_IRWXG | S_IRWXO : 0));
1227 while (mkfifoat (chdir_fd, file_name, mode) != 0)
1228 switch (maybe_recoverable (file_name, false, &interdir_made))
1237 mkfifo_error (file_name);
1241 set_stat (file_name, ¤t_stat_info, -1,
1242 mode & ~ current_umask, MODE_RWX,
1243 typeflag, false, AT_SYMLINK_NOFOLLOW);
1249 extract_volhdr (char *file_name, int typeflag)
1256 extract_failure (char *file_name, int typeflag)
1261 typedef int (*tar_extractor_t) (char *file_name, int typeflag);
1265 /* Prepare to extract a file. Find extractor function.
1266 Return zero if extraction should not proceed. */
1269 prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
1273 if (EXTRACT_OVER_PIPE)
1276 /* Select the extractor */
1279 case GNUTYPE_SPARSE:
1280 *fun = extract_file;
1287 /* Appears to be a file. But BSD tar uses the convention that a slash
1288 suffix means a directory. */
1289 if (current_stat_info.had_trailing_slash)
1293 *fun = extract_file;
1299 *fun = extract_symlink;
1303 *fun = extract_link;
1308 current_stat_info.stat.st_mode |= S_IFCHR;
1309 *fun = extract_node;
1315 current_stat_info.stat.st_mode |= S_IFBLK;
1316 *fun = extract_node;
1320 #if HAVE_MKFIFO || defined mkfifo
1322 *fun = extract_fifo;
1327 case GNUTYPE_DUMPDIR:
1329 if (current_stat_info.is_dumpdir)
1330 delay_directory_restore_option = true;
1333 case GNUTYPE_VOLHDR:
1334 *fun = extract_volhdr;
1337 case GNUTYPE_MULTIVOL:
1339 _("%s: Cannot extract -- file is continued from another volume"),
1340 quotearg_colon (current_stat_info.file_name)));
1341 *fun = extract_failure;
1344 case GNUTYPE_LONGNAME:
1345 case GNUTYPE_LONGLINK:
1346 ERROR ((0, 0, _("Unexpected long name header")));
1347 *fun = extract_failure;
1351 WARNOPT (WARN_UNKNOWN_CAST,
1353 _("%s: Unknown file type `%c', extracted as normal file"),
1354 quotearg_colon (file_name), typeflag));
1355 *fun = extract_file;
1358 /* Determine whether the extraction should proceed */
1362 switch (old_files_option)
1364 case UNLINK_FIRST_OLD_FILES:
1365 if (!remove_any_file (file_name,
1366 recursive_unlink_option ? RECURSIVE_REMOVE_OPTION
1367 : ORDINARY_REMOVE_OPTION)
1368 && errno && errno != ENOENT)
1370 unlink_error (file_name);
1375 case KEEP_NEWER_FILES:
1376 if (file_newer_p (file_name, 0, ¤t_stat_info))
1378 WARNOPT (WARN_IGNORE_NEWER,
1379 (0, 0, _("Current %s is newer or same age"),
1380 quote (file_name)));
1392 /* Extract a file from the archive. */
1394 extract_archive (void)
1397 tar_extractor_t fun;
1399 fatal_exit_hook = extract_finish;
1401 set_next_block_after (current_header);
1403 if (!current_stat_info.file_name[0]
1404 || (interactive_option
1405 && !confirm ("extract", current_stat_info.file_name)))
1411 /* Print the block from current_header and current_stat. */
1413 print_header (¤t_stat_info, current_header, -1);
1415 /* Restore stats for all non-ancestor directories, unless
1416 it is an incremental archive.
1417 (see NOTICE in the comment to delay_set_stat above) */
1418 if (!delay_directory_restore_option)
1420 int dir = chdir_current;
1421 apply_nonancestor_delayed_set_stat (current_stat_info.file_name, 0);
1425 /* Take a safety backup of a previously existing file. */
1428 if (!maybe_backup_file (current_stat_info.file_name, 0))
1431 ERROR ((0, e, _("%s: Was unable to backup this file"),
1432 quotearg_colon (current_stat_info.file_name)));
1437 /* Extract the archive entry according to its type. */
1439 typeflag = sparse_member_p (¤t_stat_info) ?
1440 GNUTYPE_SPARSE : current_header->header.typeflag;
1442 if (prepare_to_extract (current_stat_info.file_name, typeflag, &fun))
1444 if (fun && (*fun) (current_stat_info.file_name, typeflag)
1446 undo_last_backup ();
1453 /* Extract the links whose final extraction were delayed. */
1455 apply_delayed_links (void)
1457 struct delayed_link *ds;
1459 for (ds = delayed_link_head; ds; )
1461 struct string_list *sources = ds->sources;
1462 char const *valid_source = 0;
1464 chdir_do (ds->change_dir);
1466 for (sources = ds->sources; sources; sources = sources->next)
1468 char const *source = sources->string;
1471 /* Make sure the placeholder file is still there. If not,
1472 don't create a link, as the placeholder was probably
1473 removed by a later extraction. */
1474 if (fstatat (chdir_fd, source, &st, AT_SYMLINK_NOFOLLOW) == 0
1475 && st.st_dev == ds->dev
1476 && st.st_ino == ds->ino
1477 && timespec_cmp (get_stat_ctime (&st), ds->ctime) == 0)
1479 /* Unlink the placeholder, then create a hard link if possible,
1480 a symbolic link otherwise. */
1481 if (unlinkat (chdir_fd, source, 0) != 0)
1482 unlink_error (source);
1483 else if (valid_source
1484 && (linkat (chdir_fd, valid_source, chdir_fd, source, 0)
1487 else if (!ds->is_symlink)
1489 if (linkat (chdir_fd, ds->target, chdir_fd, source, 0) != 0)
1490 link_error (ds->target, source);
1492 else if (symlinkat (ds->target, chdir_fd, source) != 0)
1493 symlink_error (ds->target, source);
1496 struct tar_stat_info st1;
1497 st1.stat.st_mode = ds->mode;
1498 st1.stat.st_uid = ds->uid;
1499 st1.stat.st_gid = ds->gid;
1500 st1.atime = ds->atime;
1501 st1.mtime = ds->mtime;
1502 set_stat (source, &st1, -1, 0, 0, SYMTYPE,
1503 false, AT_SYMLINK_NOFOLLOW);
1504 valid_source = source;
1509 for (sources = ds->sources; sources; )
1511 struct string_list *next = sources->next;
1517 struct delayed_link *next = ds->next;
1523 delayed_link_head = 0;
1526 /* Finish the extraction of an archive. */
1528 extract_finish (void)
1530 /* First, fix the status of ordinary directories that need fixing. */
1531 apply_nonancestor_delayed_set_stat ("", 0);
1533 /* Then, apply delayed links, so that they don't affect delayed
1534 directory status-setting for ordinary directories. */
1535 apply_delayed_links ();
1537 /* Finally, fix the status of directories that are ancestors
1538 of delayed links. */
1539 apply_nonancestor_delayed_set_stat ("", 1);
1543 rename_directory (char *src, char *dst)
1545 if (renameat (chdir_fd, src, chdir_fd, dst) != 0)
1553 if (make_directories (dst, &interdir_made) == 0)
1555 if (renameat (chdir_fd, src, chdir_fd, dst) == 0)
1562 /* FIXME: Fall back to recursive copying */
1568 ERROR ((0, e, _("Cannot rename %s to %s"),