mirror of https://github.com/borgbackup/borg.git
597 lines
27 KiB
Python
597 lines
27 KiB
Python
import configparser
|
|
import os
|
|
import shutil
|
|
import stat
|
|
from binascii import unhexlify
|
|
from collections import namedtuple
|
|
|
|
import msgpack
|
|
|
|
from .logger import create_logger
|
|
|
|
logger = create_logger()
|
|
|
|
from .constants import CACHE_README
|
|
from .hashindex import ChunkIndex, ChunkIndexEntry
|
|
from .helpers import Location
|
|
from .helpers import Error
|
|
from .helpers import get_cache_dir, get_security_dir
|
|
from .helpers import int_to_bigint, bigint_to_int, bin_to_hex
|
|
from .helpers import format_file_size
|
|
from .helpers import safe_ns
|
|
from .helpers import yes, hostname_is_unique
|
|
from .helpers import remove_surrogates
|
|
from .helpers import ProgressIndicatorPercent, ProgressIndicatorMessage
|
|
from .item import ArchiveItem, ChunkListEntry
|
|
from .crypto.key import PlaintextKey
|
|
from .locking import Lock
|
|
from .platform import SaveFile
|
|
from .remote import cache_if_remote
|
|
|
|
FileCacheEntry = namedtuple('FileCacheEntry', 'age inode size mtime chunk_ids')
|
|
|
|
|
|
class SecurityManager:
|
|
def __init__(self, repository):
|
|
self.repository = repository
|
|
self.dir = get_security_dir(repository.id_str)
|
|
self.key_type_file = os.path.join(self.dir, 'key-type')
|
|
self.location_file = os.path.join(self.dir, 'location')
|
|
self.manifest_ts_file = os.path.join(self.dir, 'manifest-timestamp')
|
|
|
|
def known(self):
|
|
return os.path.exists(self.key_type_file)
|
|
|
|
def key_matches(self, key):
|
|
if not self.known():
|
|
return False
|
|
try:
|
|
with open(self.key_type_file, 'r') as fd:
|
|
type = fd.read()
|
|
return type == str(key.TYPE)
|
|
except OSError as exc:
|
|
logger.warning('Could not read/parse key type file: %s', exc)
|
|
|
|
def save(self, manifest, key, cache):
|
|
logger.debug('security: saving state for %s to %s', self.repository.id_str, self.dir)
|
|
current_location = cache.repository._location.canonical_path()
|
|
logger.debug('security: current location %s', current_location)
|
|
logger.debug('security: key type %s', str(key.TYPE))
|
|
logger.debug('security: manifest timestamp %s', manifest.timestamp)
|
|
with open(self.location_file, 'w') as fd:
|
|
fd.write(current_location)
|
|
with open(self.key_type_file, 'w') as fd:
|
|
fd.write(str(key.TYPE))
|
|
with open(self.manifest_ts_file, 'w') as fd:
|
|
fd.write(manifest.timestamp)
|
|
|
|
def assert_location_matches(self, cache):
|
|
# Warn user before sending data to a relocated repository
|
|
try:
|
|
with open(self.location_file) as fd:
|
|
previous_location = fd.read()
|
|
logger.debug('security: read previous_location %r', previous_location)
|
|
except FileNotFoundError:
|
|
logger.debug('security: previous_location file %s not found', self.location_file)
|
|
previous_location = None
|
|
except OSError as exc:
|
|
logger.warning('Could not read previous location file: %s', exc)
|
|
previous_location = None
|
|
if cache.previous_location and previous_location != cache.previous_location:
|
|
# Reconcile cache and security dir; we take the cache location.
|
|
previous_location = cache.previous_location
|
|
logger.debug('security: using previous_location of cache: %r', previous_location)
|
|
if previous_location and previous_location != self.repository._location.canonical_path():
|
|
msg = ("Warning: The repository at location {} was previously located at {}\n".format(
|
|
self.repository._location.canonical_path(), previous_location) +
|
|
"Do you want to continue? [yN] ")
|
|
if not yes(msg, false_msg="Aborting.", invalid_msg="Invalid answer, aborting.",
|
|
retry=False, env_var_override='BORG_RELOCATED_REPO_ACCESS_IS_OK'):
|
|
raise Cache.RepositoryAccessAborted()
|
|
# adapt on-disk config immediately if the new location was accepted
|
|
logger.debug('security: updating location stored in cache and security dir')
|
|
with open(self.location_file, 'w') as fd:
|
|
fd.write(cache.repository._location.canonical_path())
|
|
cache.begin_txn()
|
|
cache.commit()
|
|
|
|
def assert_no_manifest_replay(self, manifest, key, cache):
|
|
try:
|
|
with open(self.manifest_ts_file) as fd:
|
|
timestamp = fd.read()
|
|
logger.debug('security: read manifest timestamp %r', timestamp)
|
|
except FileNotFoundError:
|
|
logger.debug('security: manifest timestamp file %s not found', self.manifest_ts_file)
|
|
timestamp = ''
|
|
except OSError as exc:
|
|
logger.warning('Could not read previous location file: %s', exc)
|
|
timestamp = ''
|
|
timestamp = max(timestamp, cache.timestamp or '')
|
|
logger.debug('security: determined newest manifest timestamp as %s', timestamp)
|
|
# If repository is older than the cache or security dir something fishy is going on
|
|
if timestamp and timestamp > manifest.timestamp:
|
|
if isinstance(key, PlaintextKey):
|
|
raise Cache.RepositoryIDNotUnique()
|
|
else:
|
|
raise Cache.RepositoryReplay()
|
|
|
|
def assert_key_type(self, key, cache):
|
|
# Make sure an encrypted repository has not been swapped for an unencrypted repository
|
|
if cache.key_type is not None and cache.key_type != str(key.TYPE):
|
|
raise Cache.EncryptionMethodMismatch()
|
|
if self.known() and not self.key_matches(key):
|
|
raise Cache.EncryptionMethodMismatch()
|
|
|
|
def assert_secure(self, manifest, key, cache):
|
|
self.assert_location_matches(cache)
|
|
self.assert_key_type(key, cache)
|
|
self.assert_no_manifest_replay(manifest, key, cache)
|
|
if not self.known():
|
|
self.save(manifest, key, cache)
|
|
|
|
def assert_access_unknown(self, warn_if_unencrypted, key):
|
|
if warn_if_unencrypted and isinstance(key, PlaintextKey) and not self.known():
|
|
msg = ("Warning: Attempting to access a previously unknown unencrypted repository!\n" +
|
|
"Do you want to continue? [yN] ")
|
|
if not yes(msg, false_msg="Aborting.", invalid_msg="Invalid answer, aborting.",
|
|
retry=False, env_var_override='BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK'):
|
|
raise Cache.CacheInitAbortedError()
|
|
|
|
|
|
class Cache:
|
|
"""Client Side cache
|
|
"""
|
|
class RepositoryIDNotUnique(Error):
|
|
"""Cache is newer than repository - do you have multiple, independently updated repos with same ID?"""
|
|
|
|
class RepositoryReplay(Error):
|
|
"""Cache is newer than repository - this is either an attack or unsafe (multiple repos with same ID)"""
|
|
|
|
class CacheInitAbortedError(Error):
|
|
"""Cache initialization aborted"""
|
|
|
|
class RepositoryAccessAborted(Error):
|
|
"""Repository access aborted"""
|
|
|
|
class EncryptionMethodMismatch(Error):
|
|
"""Repository encryption method changed since last access, refusing to continue"""
|
|
|
|
@staticmethod
|
|
def break_lock(repository, path=None):
|
|
path = path or os.path.join(get_cache_dir(), repository.id_str)
|
|
Lock(os.path.join(path, 'lock'), exclusive=True).break_lock()
|
|
|
|
@staticmethod
|
|
def destroy(repository, path=None):
|
|
"""destroy the cache for ``repository`` or at ``path``"""
|
|
path = path or os.path.join(get_cache_dir(), repository.id_str)
|
|
config = os.path.join(path, 'config')
|
|
if os.path.exists(config):
|
|
os.remove(config) # kill config first
|
|
shutil.rmtree(path)
|
|
|
|
def __init__(self, repository, key, manifest, path=None, sync=True, do_files=False, warn_if_unencrypted=True,
|
|
progress=False, lock_wait=None):
|
|
"""
|
|
:param do_files: use file metadata cache
|
|
:param warn_if_unencrypted: print warning if accessing unknown unencrypted repository
|
|
:param lock_wait: timeout for lock acquisition (None: return immediately if lock unavailable)
|
|
:param sync: do :meth:`.sync`
|
|
"""
|
|
self.lock = None
|
|
self.timestamp = None
|
|
self.lock = None
|
|
self.txn_active = False
|
|
self.repository = repository
|
|
self.key = key
|
|
self.manifest = manifest
|
|
self.progress = progress
|
|
self.path = path or os.path.join(get_cache_dir(), repository.id_str)
|
|
self.security_manager = SecurityManager(repository)
|
|
self.do_files = do_files
|
|
# Warn user before sending data to a never seen before unencrypted repository
|
|
if not os.path.exists(self.path):
|
|
self.security_manager.assert_access_unknown(warn_if_unencrypted, key)
|
|
self.create()
|
|
self.open(lock_wait=lock_wait)
|
|
try:
|
|
self.security_manager.assert_secure(manifest, key, self)
|
|
if sync and self.manifest.id != self.manifest_id:
|
|
self.sync()
|
|
self.commit()
|
|
except:
|
|
self.close()
|
|
raise
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, exc_type, exc_val, exc_tb):
|
|
self.close()
|
|
|
|
def __str__(self):
|
|
fmt = """\
|
|
All archives: {0.total_size:>20s} {0.total_csize:>20s} {0.unique_csize:>20s}
|
|
|
|
Unique chunks Total chunks
|
|
Chunk index: {0.total_unique_chunks:20d} {0.total_chunks:20d}"""
|
|
return fmt.format(self.format_tuple())
|
|
|
|
Summary = namedtuple('Summary', ['total_size', 'total_csize', 'unique_size', 'unique_csize', 'total_unique_chunks',
|
|
'total_chunks'])
|
|
|
|
def stats(self):
|
|
# XXX: this should really be moved down to `hashindex.pyx`
|
|
stats = self.Summary(*self.chunks.summarize())._asdict()
|
|
return stats
|
|
|
|
def format_tuple(self):
|
|
stats = self.stats()
|
|
for field in ['total_size', 'total_csize', 'unique_csize']:
|
|
stats[field] = format_file_size(stats[field])
|
|
return self.Summary(**stats)
|
|
|
|
def chunks_stored_size(self):
|
|
return self.stats()['unique_csize']
|
|
|
|
def create(self):
|
|
"""Create a new empty cache at `self.path`
|
|
"""
|
|
os.makedirs(self.path)
|
|
with open(os.path.join(self.path, 'README'), 'w') as fd:
|
|
fd.write(CACHE_README)
|
|
config = configparser.ConfigParser(interpolation=None)
|
|
config.add_section('cache')
|
|
config.set('cache', 'version', '1')
|
|
config.set('cache', 'repository', self.repository.id_str)
|
|
config.set('cache', 'manifest', '')
|
|
with SaveFile(os.path.join(self.path, 'config')) as fd:
|
|
config.write(fd)
|
|
ChunkIndex().write(os.path.join(self.path, 'chunks').encode('utf-8'))
|
|
os.makedirs(os.path.join(self.path, 'chunks.archive.d'))
|
|
with SaveFile(os.path.join(self.path, 'files'), binary=True) as fd:
|
|
pass # empty file
|
|
|
|
def _check_upgrade(self, config_path):
|
|
try:
|
|
cache_version = self.config.getint('cache', 'version')
|
|
wanted_version = 1
|
|
if cache_version != wanted_version:
|
|
self.close()
|
|
raise Exception('%s has unexpected cache version %d (wanted: %d).' % (
|
|
config_path, cache_version, wanted_version))
|
|
except configparser.NoSectionError:
|
|
self.close()
|
|
raise Exception('%s does not look like a Borg cache.' % config_path) from None
|
|
# borg < 1.0.8rc1 had different canonicalization for the repo location (see #1655 and #1741).
|
|
cache_loc = self.config.get('cache', 'previous_location', fallback=None)
|
|
if cache_loc:
|
|
repo_loc = self.repository._location.canonical_path()
|
|
rl = Location(repo_loc)
|
|
cl = Location(cache_loc)
|
|
if cl.proto == rl.proto and cl.user == rl.user and cl.host == rl.host and cl.port == rl.port \
|
|
and \
|
|
cl.path and rl.path and \
|
|
cl.path.startswith('/~/') and rl.path.startswith('/./') and cl.path[3:] == rl.path[3:]:
|
|
# everything is same except the expected change in relative path canonicalization,
|
|
# update previous_location to avoid warning / user query about changed location:
|
|
self.config.set('cache', 'previous_location', repo_loc)
|
|
|
|
def _do_open(self):
|
|
self.config = configparser.ConfigParser(interpolation=None)
|
|
config_path = os.path.join(self.path, 'config')
|
|
self.config.read(config_path)
|
|
self._check_upgrade(config_path)
|
|
self.id = self.config.get('cache', 'repository')
|
|
self.manifest_id = unhexlify(self.config.get('cache', 'manifest'))
|
|
self.timestamp = self.config.get('cache', 'timestamp', fallback=None)
|
|
self.key_type = self.config.get('cache', 'key_type', fallback=None)
|
|
self.previous_location = self.config.get('cache', 'previous_location', fallback=None)
|
|
self.chunks = ChunkIndex.read(os.path.join(self.path, 'chunks').encode('utf-8'))
|
|
self.files = None
|
|
|
|
def open(self, lock_wait=None):
|
|
if not os.path.isdir(self.path):
|
|
raise Exception('%s Does not look like a Borg cache' % self.path)
|
|
self.lock = Lock(os.path.join(self.path, 'lock'), exclusive=True, timeout=lock_wait, kill_stale_locks=hostname_is_unique()).acquire()
|
|
self.rollback()
|
|
|
|
def close(self):
|
|
if self.lock is not None:
|
|
self.lock.release()
|
|
self.lock = None
|
|
|
|
def _read_files(self):
|
|
self.files = {}
|
|
self._newest_mtime = None
|
|
logger.debug('Reading files cache ...')
|
|
with open(os.path.join(self.path, 'files'), 'rb') as fd:
|
|
u = msgpack.Unpacker(use_list=True)
|
|
while True:
|
|
data = fd.read(64 * 1024)
|
|
if not data:
|
|
break
|
|
u.feed(data)
|
|
for path_hash, item in u:
|
|
entry = FileCacheEntry(*item)
|
|
# in the end, this takes about 240 Bytes per file
|
|
self.files[path_hash] = msgpack.packb(entry._replace(age=entry.age + 1))
|
|
|
|
def begin_txn(self):
|
|
# Initialize transaction snapshot
|
|
pi = ProgressIndicatorMessage(msgid='cache.begin_transaction')
|
|
txn_dir = os.path.join(self.path, 'txn.tmp')
|
|
os.mkdir(txn_dir)
|
|
pi.output('Initializing cache transaction: Reading config')
|
|
shutil.copy(os.path.join(self.path, 'config'), txn_dir)
|
|
pi.output('Initializing cache transaction: Reading chunks')
|
|
shutil.copy(os.path.join(self.path, 'chunks'), txn_dir)
|
|
pi.output('Initializing cache transaction: Reading files')
|
|
shutil.copy(os.path.join(self.path, 'files'), txn_dir)
|
|
os.rename(os.path.join(self.path, 'txn.tmp'),
|
|
os.path.join(self.path, 'txn.active'))
|
|
self.txn_active = True
|
|
pi.finish()
|
|
|
|
def commit(self):
|
|
"""Commit transaction
|
|
"""
|
|
if not self.txn_active:
|
|
return
|
|
self.security_manager.save(self.manifest, self.key, self)
|
|
pi = ProgressIndicatorMessage(msgid='cache.commit')
|
|
if self.files is not None:
|
|
if self._newest_mtime is None:
|
|
# was never set because no files were modified/added
|
|
self._newest_mtime = 2 ** 63 - 1 # nanoseconds, good until y2262
|
|
ttl = int(os.environ.get('BORG_FILES_CACHE_TTL', 20))
|
|
pi.output('Saving files cache')
|
|
with SaveFile(os.path.join(self.path, 'files'), binary=True) as fd:
|
|
for path_hash, item in self.files.items():
|
|
# Only keep files seen in this backup that are older than newest mtime seen in this backup -
|
|
# this is to avoid issues with filesystem snapshots and mtime granularity.
|
|
# Also keep files from older backups that have not reached BORG_FILES_CACHE_TTL yet.
|
|
entry = FileCacheEntry(*msgpack.unpackb(item))
|
|
if entry.age == 0 and bigint_to_int(entry.mtime) < self._newest_mtime or \
|
|
entry.age > 0 and entry.age < ttl:
|
|
msgpack.pack((path_hash, entry), fd)
|
|
pi.output('Saving cache config')
|
|
self.config.set('cache', 'manifest', self.manifest.id_str)
|
|
self.config.set('cache', 'timestamp', self.manifest.timestamp)
|
|
self.config.set('cache', 'key_type', str(self.key.TYPE))
|
|
self.config.set('cache', 'previous_location', self.repository._location.canonical_path())
|
|
with SaveFile(os.path.join(self.path, 'config')) as fd:
|
|
self.config.write(fd)
|
|
pi.output('Saving chunks cache')
|
|
self.chunks.write(os.path.join(self.path, 'chunks').encode('utf-8'))
|
|
os.rename(os.path.join(self.path, 'txn.active'),
|
|
os.path.join(self.path, 'txn.tmp'))
|
|
shutil.rmtree(os.path.join(self.path, 'txn.tmp'))
|
|
self.txn_active = False
|
|
pi.finish()
|
|
|
|
def rollback(self):
|
|
"""Roll back partial and aborted transactions
|
|
"""
|
|
# Remove partial transaction
|
|
if os.path.exists(os.path.join(self.path, 'txn.tmp')):
|
|
shutil.rmtree(os.path.join(self.path, 'txn.tmp'))
|
|
# Roll back active transaction
|
|
txn_dir = os.path.join(self.path, 'txn.active')
|
|
if os.path.exists(txn_dir):
|
|
shutil.copy(os.path.join(txn_dir, 'config'), self.path)
|
|
shutil.copy(os.path.join(txn_dir, 'chunks'), self.path)
|
|
shutil.copy(os.path.join(txn_dir, 'files'), self.path)
|
|
os.rename(txn_dir, os.path.join(self.path, 'txn.tmp'))
|
|
if os.path.exists(os.path.join(self.path, 'txn.tmp')):
|
|
shutil.rmtree(os.path.join(self.path, 'txn.tmp'))
|
|
self.txn_active = False
|
|
self._do_open()
|
|
|
|
def sync(self):
|
|
"""Re-synchronize chunks cache with repository.
|
|
|
|
Maintains a directory with known backup archive indexes, so it only
|
|
needs to fetch infos from repo and build a chunk index once per backup
|
|
archive.
|
|
If out of sync, missing archive indexes get added, outdated indexes
|
|
get removed and a new master chunks index is built by merging all
|
|
archive indexes.
|
|
"""
|
|
archive_path = os.path.join(self.path, 'chunks.archive.d')
|
|
|
|
def mkpath(id, suffix=''):
|
|
id_hex = bin_to_hex(id)
|
|
path = os.path.join(archive_path, id_hex + suffix)
|
|
return path.encode('utf-8')
|
|
|
|
def cached_archives():
|
|
if self.do_cache:
|
|
fns = os.listdir(archive_path)
|
|
# filenames with 64 hex digits == 256bit
|
|
return set(unhexlify(fn) for fn in fns if len(fn) == 64)
|
|
else:
|
|
return set()
|
|
|
|
def repo_archives():
|
|
return set(info.id for info in self.manifest.archives.list())
|
|
|
|
def cleanup_outdated(ids):
|
|
for id in ids:
|
|
os.unlink(mkpath(id))
|
|
|
|
def fetch_and_build_idx(archive_id, repository, key, chunk_idx):
|
|
cdata = repository.get(archive_id)
|
|
data = key.decrypt(archive_id, cdata)
|
|
chunk_idx.add(archive_id, 1, len(data), len(cdata))
|
|
archive = ArchiveItem(internal_dict=msgpack.unpackb(data))
|
|
if archive.version != 1:
|
|
raise Exception('Unknown archive metadata version')
|
|
unpacker = msgpack.Unpacker()
|
|
for item_id, chunk in zip(archive.items, repository.get_many(archive.items)):
|
|
data = key.decrypt(item_id, chunk)
|
|
chunk_idx.add(item_id, 1, len(data), len(chunk))
|
|
unpacker.feed(data)
|
|
for item in unpacker:
|
|
if not isinstance(item, dict):
|
|
logger.error('Error: Did not get expected metadata dict - archive corrupted!')
|
|
continue
|
|
for chunk_id, size, csize in item.get(b'chunks', []):
|
|
chunk_idx.add(chunk_id, 1, size, csize)
|
|
if self.do_cache:
|
|
fn = mkpath(archive_id)
|
|
fn_tmp = mkpath(archive_id, suffix='.tmp')
|
|
try:
|
|
chunk_idx.write(fn_tmp)
|
|
except Exception:
|
|
os.unlink(fn_tmp)
|
|
else:
|
|
os.rename(fn_tmp, fn)
|
|
|
|
def lookup_name(archive_id):
|
|
for info in self.manifest.archives.list():
|
|
if info.id == archive_id:
|
|
return info.name
|
|
|
|
def create_master_idx(chunk_idx):
|
|
logger.info('Synchronizing chunks cache...')
|
|
cached_ids = cached_archives()
|
|
archive_ids = repo_archives()
|
|
logger.info('Archives: %d, w/ cached Idx: %d, w/ outdated Idx: %d, w/o cached Idx: %d.' % (
|
|
len(archive_ids), len(cached_ids),
|
|
len(cached_ids - archive_ids), len(archive_ids - cached_ids), ))
|
|
# deallocates old hashindex, creates empty hashindex:
|
|
chunk_idx.clear()
|
|
cleanup_outdated(cached_ids - archive_ids)
|
|
if archive_ids:
|
|
chunk_idx = None
|
|
if self.progress:
|
|
pi = ProgressIndicatorPercent(total=len(archive_ids), step=0.1,
|
|
msg='%3.0f%% Syncing chunks cache. Processing archive %s',
|
|
msgid='cache.sync')
|
|
for archive_id in archive_ids:
|
|
archive_name = lookup_name(archive_id)
|
|
if self.progress:
|
|
pi.show(info=[remove_surrogates(archive_name)])
|
|
if self.do_cache:
|
|
if archive_id in cached_ids:
|
|
archive_chunk_idx_path = mkpath(archive_id)
|
|
logger.info("Reading cached archive chunk index for %s ..." % archive_name)
|
|
archive_chunk_idx = ChunkIndex.read(archive_chunk_idx_path)
|
|
else:
|
|
logger.info('Fetching and building archive index for %s ...' % archive_name)
|
|
archive_chunk_idx = ChunkIndex()
|
|
fetch_and_build_idx(archive_id, repository, self.key, archive_chunk_idx)
|
|
logger.info("Merging into master chunks index ...")
|
|
if chunk_idx is None:
|
|
# we just use the first archive's idx as starting point,
|
|
# to avoid growing the hash table from 0 size and also
|
|
# to save 1 merge call.
|
|
chunk_idx = archive_chunk_idx
|
|
else:
|
|
chunk_idx.merge(archive_chunk_idx)
|
|
else:
|
|
chunk_idx = chunk_idx or ChunkIndex()
|
|
logger.info('Fetching archive index for %s ...' % archive_name)
|
|
fetch_and_build_idx(archive_id, repository, self.key, chunk_idx)
|
|
if self.progress:
|
|
pi.finish()
|
|
logger.info('Done.')
|
|
return chunk_idx
|
|
|
|
def legacy_cleanup():
|
|
"""bring old cache dirs into the desired state (cleanup and adapt)"""
|
|
try:
|
|
os.unlink(os.path.join(self.path, 'chunks.archive'))
|
|
except:
|
|
pass
|
|
try:
|
|
os.unlink(os.path.join(self.path, 'chunks.archive.tmp'))
|
|
except:
|
|
pass
|
|
try:
|
|
os.mkdir(archive_path)
|
|
except:
|
|
pass
|
|
|
|
self.begin_txn()
|
|
with cache_if_remote(self.repository) as repository:
|
|
legacy_cleanup()
|
|
# TEMPORARY HACK: to avoid archive index caching, create a FILE named ~/.cache/borg/REPOID/chunks.archive.d -
|
|
# this is only recommended if you have a fast, low latency connection to your repo (e.g. if repo is local disk)
|
|
self.do_cache = os.path.isdir(archive_path)
|
|
self.chunks = create_master_idx(self.chunks)
|
|
|
|
def add_chunk(self, id, chunk, stats, overwrite=False, wait=True):
|
|
if not self.txn_active:
|
|
self.begin_txn()
|
|
size = len(chunk)
|
|
refcount = self.seen_chunk(id, size)
|
|
if refcount and not overwrite:
|
|
return self.chunk_incref(id, stats)
|
|
data = self.key.encrypt(chunk)
|
|
csize = len(data)
|
|
self.repository.put(id, data, wait=wait)
|
|
self.chunks.add(id, 1, size, csize)
|
|
stats.update(size, csize, not refcount)
|
|
return ChunkListEntry(id, size, csize)
|
|
|
|
def seen_chunk(self, id, size=None):
|
|
refcount, stored_size, _ = self.chunks.get(id, ChunkIndexEntry(0, None, None))
|
|
if size is not None and stored_size is not None and size != stored_size:
|
|
# we already have a chunk with that id, but different size.
|
|
# this is either a hash collision (unlikely) or corruption or a bug.
|
|
raise Exception("chunk has same id [%r], but different size (stored: %d new: %d)!" % (
|
|
id, stored_size, size))
|
|
return refcount
|
|
|
|
def chunk_incref(self, id, stats):
|
|
if not self.txn_active:
|
|
self.begin_txn()
|
|
count, size, csize = self.chunks.incref(id)
|
|
stats.update(size, csize, False)
|
|
return ChunkListEntry(id, size, csize)
|
|
|
|
def chunk_decref(self, id, stats, wait=True):
|
|
if not self.txn_active:
|
|
self.begin_txn()
|
|
count, size, csize = self.chunks.decref(id)
|
|
if count == 0:
|
|
del self.chunks[id]
|
|
self.repository.delete(id, wait=wait)
|
|
stats.update(-size, -csize, True)
|
|
else:
|
|
stats.update(-size, -csize, False)
|
|
|
|
def file_known_and_unchanged(self, path_hash, st, ignore_inode=False):
|
|
if not (self.do_files and stat.S_ISREG(st.st_mode)):
|
|
return None
|
|
if self.files is None:
|
|
self._read_files()
|
|
entry = self.files.get(path_hash)
|
|
if not entry:
|
|
return None
|
|
entry = FileCacheEntry(*msgpack.unpackb(entry))
|
|
if (entry.size == st.st_size and bigint_to_int(entry.mtime) == st.st_mtime_ns and
|
|
(ignore_inode or entry.inode == st.st_ino)):
|
|
# we ignored the inode number in the comparison above or it is still same.
|
|
# if it is still the same, replacing it in the tuple doesn't change it.
|
|
# if we ignored it, a reason for doing that is that files were moved to a new
|
|
# disk / new fs (so a one-time change of inode number is expected) and we wanted
|
|
# to avoid everything getting chunked again. to be able to re-enable the inode
|
|
# number comparison in a future backup run (and avoid chunking everything
|
|
# again at that time), we need to update the inode number in the cache with what
|
|
# we see in the filesystem.
|
|
self.files[path_hash] = msgpack.packb(entry._replace(inode=st.st_ino, age=0))
|
|
return entry.chunk_ids
|
|
else:
|
|
return None
|
|
|
|
def memorize_file(self, path_hash, st, ids):
|
|
if not (self.do_files and stat.S_ISREG(st.st_mode)):
|
|
return
|
|
mtime_ns = safe_ns(st.st_mtime_ns)
|
|
entry = FileCacheEntry(age=0, inode=st.st_ino, size=st.st_size, mtime=int_to_bigint(mtime_ns), chunk_ids=ids)
|
|
self.files[path_hash] = msgpack.packb(entry)
|
|
self._newest_mtime = max(self._newest_mtime or 0, mtime_ns)
|