The patch leverages the existing -C code. In order to do that, every
entry in the wd[] table gets another companion entry in the table that
represents the --one-top-level directory. There is one additional field
in each entry that allows skipping the companion entries if they are not
desired.
The actual directory is created lazily by chdir_do() if needed, as you
requested, to avoid empty "a/foo" after --one-top-level=foo -C a -C b.
The patch "by the way" fixes also extraction of hardlinks with
--one-top-level which currently is broken in the typical case (the
transform is not applied to the target, so the hardlink is wrong).
The patch does not yet handle the --show-transformed case with
--one-top-level that you discussed in another subthread. As a result, two
tests now fail (onetop02.at and onetop04.at). I suppose that this would
be quite easy to fix.
Another issue that I am aware of is that I am not sure whether to call
repair_delayed_set_stat and/or delay_set_stat on the newly created
directories like extract_dir() does (the whole delay_set code is abit
mysterious to me).
Use of --create together with --one-top-level should probably be
forbidden, as unlink.c uses wd[] in a way that will likely break in the
presence of companion entries (the chdir_do call in
flush_deferred_unlinks).
Show the one-top-level arg as a transformation
Although this might help (or hurt) performance, the main
motivation is to make it easier in future commits
to prevent tarballs from escaping the extraction directory.
* src/common.h: (BADFD): New constant.
(struct fdbase): New type.
* src/create.c (dump_file0): Use parent->fd instead of caching
it into a local, as the latter approach is now awkward.
* src/extract.c (extract_link): Don’t save errno unless needed.
* src/misc.c (safer_rmdir): New arg F. All callers changed.
(maybe_backup_file): Construct full after_backup_name, now
that find_backup_file_name no longer does that for us.
(chdir_fd): Now static not extern, as other modules now use fdbase.
(fdbase_cache): New static var.
(fdbase_clear): New function. Call it whenever removing
or renaming directories or symlinks to directories.
(fdbase_opendir): New static function.
(fdbase, fdbase1): New functions. Call them whenever the
code formerly passed chdir_fd to a syscall.
* src/extract.c (struct delayed_set_stat, struct delayed_link):
* src/misc.c (normalize_filename, wd_count, chdir_count)
(chdir_arg, tar_getcdpath):
* src/names.c (name_gather, addname, add_hierarchy_to_namelist):
* src/unlink.c (struct deferred_unlink, flush_deferred_unlinks):
Use idx_t, not int, for directory indexes, so as to not
limit their number to INT_MAX; this is theoretically possible
if -T is used.
* src/names.c (name_next_elt, name_next):
Use bool for boolean.
* paxutils: Update.
* src/unlink.c (flush_deferred_unlinks): OpenSolaris sets EEXIST
instead of ENOTEMPTY if trying to remove a non-empty directory.
* tests/numeric.at: Avoid using awk -v: some older awks don't support
that option. Also fix environment variable usage.
* tests/onetop05.at: Skip test if unable to set initial directory
mode bits.
* tests/sparse06.at: Use --quiet option.
* src/unlink.c (dunlink_insert): New function.
(flush_deferred_unlinks): Skip cwds and nonempty directories
at the first pass. If force is requested, run a second pass
removing them.
(queue_deferred_unlink): Make sure current working directory
entries are sorted in descending order by the value of dir_idx.
This makes sure they will be removed in right order, which works
around unlinkat bug on FreeBSD and GNU/Hurd.
* tests/remfiles08b.at: Remove expected failure.
* tests/remfiles09b.at: Likewise.
Problem reported by Thorsten Hirsch in:
http://lists.gnu.org/archive/html/bug-tar/2014-04/msg00011.html
* src/unlink.c (flush_deferred_unlinks):
Do not attempt to find the parent of "." when "." is
at the top level.
* tests/remfiles10.at: New file.
* tests/Makefile.am (TESTSUITE_AT):
* tests/testsuite.at: Add it.
* src/common.h (tar_dirname): New function.
* src/misc.c (normalize_filename_x): Make extern.
(tar_dirname): New function.
(tar_getcwd): Take into account absoulte pathnames.
* src/unlink.c (deferred_unlink) <dir_idx>: New member; keeps the
value of chdir_current at the moment of structure allocation.
(flush_deferred_unlinks): Use chdir_do and relative addressing.
(queue_deferred_unlink): Initialize dir_idx.
* tests/Makefile.am: Add new tests.
* tests/testsuite.at: Add new tests.
* tests/remfiles06.at: Fix description.
* tests/remfiles07.at: Fix description.
* tests/remfiles08.at: New test case.
This lint was found by GCC 4.6.2 on Fedora 15 x86-64.
* src/buffer.c (buffer_write_global_xheader, mv_end, set_start_time)
(compute_duration, print_total_stats, flush_read, flush_write):
* src/checkpoint.c (checkpoint_finish_compile):
* src/list.c (test_archive_label):
* src/misc.c (chdir_count):
* src/names.c (const):
* src/unlink.c (finish_deferred_unlinks):
Define with (void) instead of with (), for slightly-better C type
checking and to avoid a GCC warning.
* src/compare.c (diff_dumpdir):
* src/tar.c (parse_owner_group): Remove unused local.
* src/misc.c (chdir_do):
* src/tar.c (add_exclude_array): Rename local to avoid shadowing.
(LOW_DENSITY_NUM, MID_DENSITY_NUM, HIGH_DENSITY_NUM):
Define only if needed.
* src/update.c (update_archive): Initialize a local; this fixes
what appears to be a real bug.
This change replaces traditional functions like 'open' with the
POSIX.1-2008 functions like 'openat'. Mostly this is an internal
refactoring change, in preparation for further changes to close
some races.
* gnulib.modules: Add faccessat, linkat, mkfifoat, renameat, symlinkat.
Remove save-cwd.
* src/Makefile.am (tar_LDADD): Add $(LIB_EACCESS).
* tests/Makefile.am (LDADD): Likewise.
* src/common.h (chdir_fd): New extern var.
* src/compare.c (diff_file, diff_multivol): Use openat instead of open.
* src/create.c (create_archive, restore_parent_fd): Likewise.
* src/extract.c (create_placeholder_file): Likewise.
* src/names.c (collect_and_sort_names): Likewise.
* src/update.c (append_file): Likewise.
* src/compare.c (diff_symlink): Use readlinkat instead of readlink.
* src/compare.c (diff_file): Use chdir_fd instead of AT_FDCWD.
* src/create.c (subfile_open, dump_file0): Likewise.
* src/extract.c (fd_chmod, fd_chown, fd_stat, set_stat):
(repair_delayed_set_stat, apply_nonancestor_delayed_set_stat):
Likewise.
* src/extract.c (mark_after_links, file_newer_p, extract_dir):
(extract_link, apply_delayed_links):
Use fstatat rather than stat or lstat.
* src/misc.c (maybe_backup_file, deref_stat): Likewise.
* src/extract.c (make_directories): Use mkdirat rather than mkdir.
Use faccessat rather than access. This fixes a minor permissions
bug when tar is running setuid (who would want to do that?!).
(open_output_file): Use openat rather than open.
In the process, this removes support for Masscomp's O_CTG files,
which aren't compatible with openat's signature. Masscomp! Wow!
That's a blast from the past. As far as I know, that operating
system hasn't been supported for more than 20 years.
(extract_link, apply_delayed_links):
Use linkat rather than link.
(extract_symlink, apply_delayed_links):
Use symlinkat rather than symlink.
(extract_node): Use mknodat rather than mknod.
(extract_fifo): Use mkfifoat rather than mkfifo.
(apply_delayed_links): Use unlinkat rather than unlink or rmdir.
* src/misc.c (safer_rmdir, remove_any_file): Likewise.
* src/unlink.c (flush_deferred_unlinks): Likewise.
* src/extract.c (rename_directory): Use renameat rather than rename.
* src/misc.c (maybe_backup_file, undo_last_backup): Likewise.
* src/misc.c: Don't include <save-cwd.h>; no longer needed now
that we're using openat etc.
(struct wd): Add member fd. Remove members err and fd. All uses
changed.
(CHDIR_CACHE_SIZE): New constant.
(wdcache, wdcache_count, chdir_fd): New vars.
(chdir_do): Use openat rather than save_cwd. Keep the cache up
to date. This code won't scale well, but is good enough for now.
* src/update.c (update_archive): Use openat + fdopendir +
streamsavedir rather than savedir.
This file is a placeholder. It will be replaced with the actual ChangeLog
by make dist. Run make ChangeLog if you wish to create it earlier.
Make sure the files are deleted only if they were succesfully stored
to the archive.
* src/exit.c: New file.
* src/unlink.c: New file.
* src/Makefile.am (tar_SOURCES): Add exit.c and unlink.c.
* src/common.h: Include progname.h
(program_name): Remove global.
(records_written): New extern.
(queue_deferred_unlink, finish_deferred_unlinks): New prototypes.
(fatal_exit_hook): New extern.
* src/create.c (create_archive): Call finish_deferred_unlinks.
(dump_hard_link, dump_file0): Don't actually unlink the file,
queue it to deferred_unlinks instead.
* src/delete.c (records_written): Remove extern: declared in
common.h.
* src/extract.c (extract_archive): Set fatal_exit_hook.
(fatal_exit, xalloc_die): Move to exit.c
* src/system.c (sys_wait_for_child): Exit immediately
if the child dies or exits with a non-zero status.
(sys_child_open_for_compress)
(sys_child_open_for_uncompress): Use set_program_name,
instead of setting program_name directly.
* src/tar.c (main): Use set_program_name,
instead of setting program_name directly.
* tests/Makefile.am (TESTSUITE_AT): Add remfiles01.at
and remfiles02.at.
* tests/testsuite.at: Likewise.
* tests/gzip.at: Reflect the above changes.
Pavel CahynaandPaul Eggert
Sergey Poznyakoff
Sergey Poznyakoff