fix hardlinked CACHEDIR.TAG processing, fixes #4911

This commit is contained in:
Thomas Waldmann 2020-06-14 21:43:28 +02:00
parent 29731401b5
commit d2536de4ee
1 changed files with 20 additions and 11 deletions

View File

@ -2032,24 +2032,33 @@ class ArchiveRecreater:
matcher = self.matcher
tag_files = []
tagged_dirs = []
# build hardlink masters, but only for paths ending in CACHE_TAG_NAME, so we can read hard-linked TAGs
# to support reading hard-linked CACHEDIR.TAGs (aka CACHE_TAG_NAME), similar to hardlink_masters:
cachedir_masters = {}
if self.exclude_caches:
# sadly, due to how CACHEDIR.TAG works (filename AND file [header] contents) and
# how borg deals with hardlinks (slave hardlinks referring back to master hardlinks),
# we need to pass over the archive collecting hardlink master paths.
# as seen in issue #4911, the master paths can have an arbitrary filenames,
# not just CACHEDIR.TAG.
for item in archive.iter_items(filter=lambda item: os.path.basename(item.path) == CACHE_TAG_NAME):
if stat.S_ISREG(item.mode) and 'chunks' not in item and 'source' in item:
# this is a hardlink slave, referring back to its hardlink master (via item.source)
cachedir_masters[item.source] = None # we know the key (path), but not the value (item) yet
for item in archive.iter_items(
filter=lambda item: item.path.endswith(CACHE_TAG_NAME) or matcher.match(item.path)):
if item.path.endswith(CACHE_TAG_NAME):
filter=lambda item: os.path.basename(item.path) == CACHE_TAG_NAME or matcher.match(item.path)):
if self.exclude_caches and item.path in cachedir_masters:
cachedir_masters[item.path] = item
dir, tag_file = os.path.split(item.path)
if tag_file in self.exclude_if_present:
exclude(dir, item)
if stat.S_ISREG(item.mode):
if self.exclude_caches and tag_file == CACHE_TAG_NAME:
if 'chunks' in item:
file = open_item(archive, item)
else:
file = open_item(archive, cachedir_masters[item.source])
if file.read(len(CACHE_TAG_CONTENTS)).startswith(CACHE_TAG_CONTENTS):
exclude(dir, item)
elif self.exclude_caches and tag_file == CACHE_TAG_NAME and stat.S_ISREG(item.mode):
content_item = item if 'chunks' in item else cachedir_masters[item.source]
file = open_item(archive, content_item)
if file.read(len(CACHE_TAG_CONTENTS)) == CACHE_TAG_CONTENTS:
exclude(dir, item)
matcher.add(tag_files, IECommand.Include)
matcher.add(tagged_dirs, IECommand.ExcludeNoRecurse)