support hardlinks via create_helper context manager

also: reduce code duplication
This commit is contained in:
Thomas Waldmann 2017-03-26 13:51:04 +02:00
parent e5d094d0ce
commit 9478e8abd0
1 changed files with 88 additions and 83 deletions

View File

@ -834,34 +834,54 @@ Utilization of max. archive size: {csize_max:.0%}
attrs.update(self.stat_ext_attrs(st, path))
return attrs
def process_dir(self, path, st):
item = Item(path=make_path_safe(path))
item.update(self.stat_attrs(st, path))
@contextmanager
def create_helper(self, path, st, status=None):
safe_path = make_path_safe(path)
item = Item(path=safe_path)
hardlink_master = False
hardlinked = st.st_nlink > 1
if hardlinked:
source = self.hard_links.get((st.st_ino, st.st_dev))
if source is not None:
item.source = source
status = 'h' # hardlink (to already seen inodes)
else:
hardlink_master = True
yield item, status, hardlinked, hardlink_master
# if we get here, "with"-block worked ok without error/exception, the item was processed ok...
self.add_item(item)
return 'd' # directory
# ... and added to the archive, so we can remember it to refer to it later in the archive:
if hardlink_master:
self.hard_links[(st.st_ino, st.st_dev)] = safe_path
def process_dir(self, path, st):
with self.create_helper(path, st, 'd') as (item, status, hardlinked, hardlink_master): # directory
item.update(self.stat_attrs(st, path))
return status
def process_fifo(self, path, st):
item = Item(path=make_path_safe(path))
item.update(self.stat_attrs(st, path))
self.add_item(item)
return 'f' # fifo
with self.create_helper(path, st, 'f') as (item, status, hardlinked, hardlink_master): # fifo
item.update(self.stat_attrs(st, path))
return status
def process_dev(self, path, st):
item = Item(path=make_path_safe(path), rdev=st.st_rdev)
item.update(self.stat_attrs(st, path))
self.add_item(item)
if stat.S_ISCHR(st.st_mode):
return 'c' # char device
elif stat.S_ISBLK(st.st_mode):
return 'b' # block device
with self.create_helper(path, st, None) as (item, status, hardlinked, hardlink_master): # no status yet
item.rdev = st.st_rdev
item.update(self.stat_attrs(st, path))
if stat.S_ISCHR(st.st_mode):
return 'c' # char device
elif stat.S_ISBLK(st.st_mode):
return 'b' # block device
def process_symlink(self, path, st):
with backup_io('readlink'):
source = os.readlink(path)
item = Item(path=make_path_safe(path), source=source)
item.update(self.stat_attrs(st, path))
self.add_item(item)
return 's' # symlink
with self.create_helper(path, st, 's') as (item, status, hardlinked, hardlink_master): # symlink
with backup_io('readlink'):
source = os.readlink(path)
item.source = source # XXX this overwrites hardlink slave's usage of item.source
if hardlinked:
logger.warning('hardlinked symlinks will be extracted as non-hardlinked symlinks!')
item.update(self.stat_attrs(st, path))
return status
def write_part_file(self, item, from_chunk, number):
item = Item(internal_dict=item.as_dict())
@ -925,69 +945,54 @@ Utilization of max. archive size: {csize_max:.0%}
return 'i' # stdin
def process_file(self, path, st, cache, ignore_inode=False):
status = None
safe_path = make_path_safe(path)
item = Item(path=safe_path)
hardlink_master = False
hardlinked = st.st_nlink > 1
if hardlinked:
source = self.hard_links.get((st.st_ino, st.st_dev))
if source is not None:
item.source = source
status = 'h' # regular file, hardlink (to already seen inodes)
else:
hardlink_master = True
is_special_file = is_special(st.st_mode)
if not hardlinked or hardlink_master:
if not is_special_file:
path_hash = self.key.id_hash(safe_encode(os.path.join(self.cwd, path)))
ids = cache.file_known_and_unchanged(path_hash, st, ignore_inode)
else:
# in --read-special mode, we may be called for special files.
# there should be no information in the cache about special files processed in
# read-special mode, but we better play safe as this was wrong in the past:
path_hash = ids = None
first_run = not cache.files and cache.do_files
if first_run:
logger.debug('Processing files ...')
chunks = None
if ids is not None:
# Make sure all ids are available
for id_ in ids:
if not cache.seen_chunk(id_):
break
else:
chunks = [cache.chunk_incref(id_, self.stats) for id_ in ids]
status = 'U' # regular file, unchanged
else:
status = 'A' # regular file, added
item.hardlink_master = hardlinked
item.update(self.stat_simple_attrs(st))
# Only chunkify the file if needed
if chunks is not None:
item.chunks = chunks
else:
with backup_io('open'):
fh = Archive._open_rb(path)
with os.fdopen(fh, 'rb') as fd:
self.chunk_file(item, cache, self.stats, backup_io_iter(self.chunker.chunkify(fd, fh)))
with self.create_helper(path, st, None) as (item, status, hardlinked, hardlink_master): # no status yet
is_special_file = is_special(st.st_mode)
if not hardlinked or hardlink_master:
if not is_special_file:
# we must not memorize special files, because the contents of e.g. a
# block or char device will change without its mtime/size/inode changing.
cache.memorize_file(path_hash, st, [c.id for c in item.chunks])
status = status or 'M' # regular file, modified (if not 'A' already)
self.stats.nfiles += 1
item.update(self.stat_attrs(st, path))
item.get_size(memorize=True)
if is_special_file:
# we processed a special file like a regular file. reflect that in mode,
# so it can be extracted / accessed in FUSE mount like a regular file:
item.mode = stat.S_IFREG | stat.S_IMODE(item.mode)
self.add_item(item)
if hardlink_master:
# Add the hard link reference *after* the file has been added to the archive.
self.hard_links[st.st_ino, st.st_dev] = safe_path
return status
path_hash = self.key.id_hash(safe_encode(os.path.join(self.cwd, path)))
ids = cache.file_known_and_unchanged(path_hash, st, ignore_inode)
else:
# in --read-special mode, we may be called for special files.
# there should be no information in the cache about special files processed in
# read-special mode, but we better play safe as this was wrong in the past:
path_hash = ids = None
first_run = not cache.files and cache.do_files
if first_run:
logger.debug('Processing files ...')
chunks = None
if ids is not None:
# Make sure all ids are available
for id_ in ids:
if not cache.seen_chunk(id_):
break
else:
chunks = [cache.chunk_incref(id_, self.stats) for id_ in ids]
status = 'U' # regular file, unchanged
else:
status = 'A' # regular file, added
item.hardlink_master = hardlinked
item.update(self.stat_simple_attrs(st))
# Only chunkify the file if needed
if chunks is not None:
item.chunks = chunks
else:
with backup_io('open'):
fh = Archive._open_rb(path)
with os.fdopen(fh, 'rb') as fd:
self.chunk_file(item, cache, self.stats, backup_io_iter(self.chunker.chunkify(fd, fh)))
if not is_special_file:
# we must not memorize special files, because the contents of e.g. a
# block or char device will change without its mtime/size/inode changing.
cache.memorize_file(path_hash, st, [c.id for c in item.chunks])
status = status or 'M' # regular file, modified (if not 'A' already)
self.stats.nfiles += 1
item.update(self.stat_attrs(st, path))
item.get_size(memorize=True)
if is_special_file:
# we processed a special file like a regular file. reflect that in mode,
# so it can be extracted / accessed in FUSE mount like a regular file:
item.mode = stat.S_IFREG | stat.S_IMODE(item.mode)
return status
@staticmethod
def list_archives(repository, key, manifest, cache=None):