mirror of https://github.com/borgbackup/borg.git
810 lines
31 KiB
Python
810 lines
31 KiB
Python
from datetime import datetime
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from getpass import getuser
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from itertools import groupby
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import errno
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import shutil
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import tempfile
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from .key import key_factory
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from .remote import cache_if_remote
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import msgpack
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import os
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import socket
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import stat
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import sys
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import time
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from io import BytesIO
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from . import xattr
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from .platform import acl_get, acl_set
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from .chunker import Chunker
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from .hashindex import ChunkIndex
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from .helpers import parse_timestamp, Error, uid2user, user2uid, gid2group, group2gid, \
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Manifest, Statistics, decode_dict, st_mtime_ns, make_path_safe, StableDict, int_to_bigint, bigint_to_int
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ITEMS_BUFFER = 1024 * 1024
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CHUNK_MIN = 1024
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CHUNK_MAX = 10 * 1024 * 1024
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WINDOW_SIZE = 0xfff
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CHUNK_MASK = 0xffff
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ZEROS = b'\0' * CHUNK_MAX
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utime_supports_fd = os.utime in getattr(os, 'supports_fd', {})
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utime_supports_follow_symlinks = os.utime in getattr(os, 'supports_follow_symlinks', {})
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has_mtime_ns = sys.version >= '3.3'
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has_lchmod = hasattr(os, 'lchmod')
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has_lchflags = hasattr(os, 'lchflags')
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# Python <= 3.2 raises OSError instead of PermissionError (See #164)
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try:
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PermissionError = PermissionError
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except NameError:
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PermissionError = OSError
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class DownloadPipeline:
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def __init__(self, repository, key):
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self.repository = repository
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self.key = key
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def unpack_many(self, ids, filter=None, preload=False):
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unpacker = msgpack.Unpacker(use_list=False)
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for data in self.fetch_many(ids):
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unpacker.feed(data)
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items = [decode_dict(item, (b'path', b'source', b'user', b'group')) for item in unpacker]
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if filter:
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items = [item for item in items if filter(item)]
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if preload:
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for item in items:
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if b'chunks' in item:
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self.repository.preload([c[0] for c in item[b'chunks']])
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for item in items:
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yield item
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def fetch_many(self, ids, is_preloaded=False):
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for id_, data in zip(ids, self.repository.get_many(ids, is_preloaded=is_preloaded)):
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yield self.key.decrypt(id_, data)
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class ChunkBuffer:
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BUFFER_SIZE = 1 * 1024 * 1024
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def __init__(self, key):
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self.buffer = BytesIO()
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self.packer = msgpack.Packer(unicode_errors='surrogateescape')
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self.chunks = []
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self.key = key
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self.chunker = Chunker(WINDOW_SIZE, CHUNK_MASK, CHUNK_MIN, CHUNK_MAX,self.key.chunk_seed)
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def add(self, item):
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self.buffer.write(self.packer.pack(StableDict(item)))
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if self.is_full():
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self.flush()
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def write_chunk(self, chunk):
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raise NotImplementedError
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def flush(self, flush=False):
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if self.buffer.tell() == 0:
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return
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self.buffer.seek(0)
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chunks = list(bytes(s) for s in self.chunker.chunkify(self.buffer))
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self.buffer.seek(0)
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self.buffer.truncate(0)
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# Leave the last partial chunk in the buffer unless flush is True
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end = None if flush or len(chunks) == 1 else -1
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for chunk in chunks[:end]:
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self.chunks.append(self.write_chunk(chunk))
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if end == -1:
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self.buffer.write(chunks[-1])
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def is_full(self):
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return self.buffer.tell() > self.BUFFER_SIZE
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class CacheChunkBuffer(ChunkBuffer):
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def __init__(self, cache, key, stats):
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super(CacheChunkBuffer, self).__init__(key)
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self.cache = cache
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self.stats = stats
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def write_chunk(self, chunk):
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id_, _, _ = self.cache.add_chunk(self.key.id_hash(chunk), chunk, self.stats)
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return id_
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class Archive:
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class DoesNotExist(Error):
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"""Archive {} does not exist"""
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class AlreadyExists(Error):
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"""Archive {} already exists"""
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class IncompatibleFilesystemEncodingError(Error):
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"""Failed to encode filename "{}" into file system encoding "{}". Consider configuring the LANG environment variable."""
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def __init__(self, repository, key, manifest, name, cache=None, create=False,
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checkpoint_interval=300, numeric_owner=False, progress=False):
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self.cwd = os.getcwd()
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self.key = key
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self.repository = repository
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self.cache = cache
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self.manifest = manifest
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self.hard_links = {}
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self.stats = Statistics()
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self.show_progress = progress
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self.last_progress = time.time()
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self.name = name
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self.checkpoint_interval = checkpoint_interval
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self.numeric_owner = numeric_owner
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self.pipeline = DownloadPipeline(self.repository, self.key)
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if create:
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self.items_buffer = CacheChunkBuffer(self.cache, self.key, self.stats)
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self.chunker = Chunker(WINDOW_SIZE, CHUNK_MASK, CHUNK_MIN, CHUNK_MAX, self.key.chunk_seed)
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if name in manifest.archives:
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raise self.AlreadyExists(name)
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self.last_checkpoint = time.time()
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i = 0
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while True:
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self.checkpoint_name = '%s.checkpoint%s' % (name, i and ('.%d' % i) or '')
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if self.checkpoint_name not in manifest.archives:
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break
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i += 1
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else:
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if name not in self.manifest.archives:
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raise self.DoesNotExist(name)
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info = self.manifest.archives[name]
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self.load(info[b'id'])
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def _load_meta(self, id):
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data = self.key.decrypt(id, self.repository.get(id))
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metadata = msgpack.unpackb(data)
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if metadata[b'version'] != 1:
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raise Exception('Unknown archive metadata version')
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return metadata
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def load(self, id):
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self.id = id
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self.metadata = self._load_meta(self.id)
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decode_dict(self.metadata, (b'name', b'hostname', b'username', b'time'))
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self.metadata[b'cmdline'] = [arg.decode('utf-8', 'surrogateescape') for arg in self.metadata[b'cmdline']]
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self.name = self.metadata[b'name']
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@property
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def ts(self):
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"""Timestamp of archive creation in UTC"""
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return parse_timestamp(self.metadata[b'time'])
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def __repr__(self):
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return 'Archive(%r)' % self.name
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def iter_items(self, filter=None, preload=False):
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for item in self.pipeline.unpack_many(self.metadata[b'items'], filter=filter, preload=preload):
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yield item
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def add_item(self, item):
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if self.show_progress and time.time() - self.last_progress > 0.2:
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self.stats.show_progress(item=item)
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self.last_progress = time.time()
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self.items_buffer.add(item)
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if time.time() - self.last_checkpoint > self.checkpoint_interval:
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self.write_checkpoint()
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self.last_checkpoint = time.time()
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def write_checkpoint(self):
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self.save(self.checkpoint_name)
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del self.manifest.archives[self.checkpoint_name]
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self.cache.chunk_decref(self.id, self.stats)
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def save(self, name=None, timestamp=None):
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name = name or self.name
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if name in self.manifest.archives:
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raise self.AlreadyExists(name)
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self.items_buffer.flush(flush=True)
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if timestamp is None:
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timestamp = datetime.utcnow()
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metadata = StableDict({
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'version': 1,
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'name': name,
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'items': self.items_buffer.chunks,
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'cmdline': sys.argv,
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'hostname': socket.gethostname(),
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'username': getuser(),
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'time': timestamp.isoformat(),
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})
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data = msgpack.packb(metadata, unicode_errors='surrogateescape')
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self.id = self.key.id_hash(data)
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self.cache.add_chunk(self.id, data, self.stats)
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self.manifest.archives[name] = {'id': self.id, 'time': metadata['time']}
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self.manifest.write()
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self.repository.commit()
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self.cache.commit()
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def calc_stats(self, cache):
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def add(id):
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count, size, csize = cache.chunks[id]
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stats.update(size, csize, count == 1)
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cache.chunks[id] = count - 1, size, csize
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def add_file_chunks(chunks):
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for id, _, _ in chunks:
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add(id)
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# This function is a bit evil since it abuses the cache to calculate
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# the stats. The cache transaction must be rolled back afterwards
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unpacker = msgpack.Unpacker(use_list=False)
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cache.begin_txn()
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stats = Statistics()
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add(self.id)
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for id, chunk in zip(self.metadata[b'items'], self.repository.get_many(self.metadata[b'items'])):
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add(id)
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unpacker.feed(self.key.decrypt(id, chunk))
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for item in unpacker:
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if b'chunks' in item:
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stats.nfiles += 1
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add_file_chunks(item[b'chunks'])
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cache.rollback()
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return stats
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def extract_item(self, item, restore_attrs=True, dry_run=False, stdout=False, sparse=False):
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if dry_run or stdout:
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if b'chunks' in item:
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for data in self.pipeline.fetch_many([c[0] for c in item[b'chunks']], is_preloaded=True):
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if stdout:
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sys.stdout.buffer.write(data)
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if stdout:
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sys.stdout.buffer.flush()
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return
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dest = self.cwd
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if item[b'path'].startswith('/') or item[b'path'].startswith('..'):
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raise Exception('Path should be relative and local')
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path = os.path.join(dest, item[b'path'])
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# Attempt to remove existing files, ignore errors on failure
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try:
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st = os.lstat(path)
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if stat.S_ISDIR(st.st_mode):
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os.rmdir(path)
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else:
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os.unlink(path)
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except UnicodeEncodeError:
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raise self.IncompatibleFilesystemEncodingError(path, sys.getfilesystemencoding())
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except OSError:
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pass
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mode = item[b'mode']
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if stat.S_ISREG(mode):
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if not os.path.exists(os.path.dirname(path)):
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os.makedirs(os.path.dirname(path))
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# Hard link?
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if b'source' in item:
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source = os.path.join(dest, item[b'source'])
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if os.path.exists(path):
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os.unlink(path)
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os.link(source, path)
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else:
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with open(path, 'wb') as fd:
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ids = [c[0] for c in item[b'chunks']]
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for data in self.pipeline.fetch_many(ids, is_preloaded=True):
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if sparse and ZEROS.startswith(data):
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# all-zero chunk: create a hole in a sparse file
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fd.seek(len(data), 1)
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else:
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fd.write(data)
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pos = fd.tell()
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fd.truncate(pos)
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fd.flush()
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self.restore_attrs(path, item, fd=fd.fileno())
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elif stat.S_ISDIR(mode):
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if not os.path.exists(path):
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os.makedirs(path)
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if restore_attrs:
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self.restore_attrs(path, item)
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elif stat.S_ISLNK(mode):
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if not os.path.exists(os.path.dirname(path)):
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os.makedirs(os.path.dirname(path))
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source = item[b'source']
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if os.path.exists(path):
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os.unlink(path)
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os.symlink(source, path)
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self.restore_attrs(path, item, symlink=True)
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elif stat.S_ISFIFO(mode):
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if not os.path.exists(os.path.dirname(path)):
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os.makedirs(os.path.dirname(path))
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os.mkfifo(path)
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self.restore_attrs(path, item)
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elif stat.S_ISCHR(mode) or stat.S_ISBLK(mode):
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os.mknod(path, item[b'mode'], item[b'rdev'])
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self.restore_attrs(path, item)
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else:
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raise Exception('Unknown archive item type %r' % item[b'mode'])
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def restore_attrs(self, path, item, symlink=False, fd=None):
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xattrs = item.get(b'xattrs')
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if xattrs:
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for k, v in xattrs.items():
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try:
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xattr.setxattr(fd or path, k, v, follow_symlinks=False)
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except OSError as e:
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if e.errno != errno.ENOTSUP:
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raise
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uid = gid = None
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if not self.numeric_owner:
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uid = user2uid(item[b'user'])
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gid = group2gid(item[b'group'])
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uid = item[b'uid'] if uid is None else uid
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gid = item[b'gid'] if gid is None else gid
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# This code is a bit of a mess due to os specific differences
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try:
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if fd:
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os.fchown(fd, uid, gid)
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else:
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os.lchown(path, uid, gid)
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except OSError:
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pass
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if fd:
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os.fchmod(fd, item[b'mode'])
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elif not symlink:
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os.chmod(path, item[b'mode'])
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elif has_lchmod: # Not available on Linux
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os.lchmod(path, item[b'mode'])
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mtime = bigint_to_int(item[b'mtime'])
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if fd and utime_supports_fd: # Python >= 3.3
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os.utime(fd, None, ns=(mtime, mtime))
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elif utime_supports_follow_symlinks: # Python >= 3.3
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os.utime(path, None, ns=(mtime, mtime), follow_symlinks=False)
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elif not symlink:
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os.utime(path, (mtime / 1e9, mtime / 1e9))
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acl_set(path, item, self.numeric_owner)
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# Only available on OS X and FreeBSD
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if has_lchflags and b'bsdflags' in item:
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try:
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os.lchflags(path, item[b'bsdflags'])
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except OSError:
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pass
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def rename(self, name):
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if name in self.manifest.archives:
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raise self.AlreadyExists(name)
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metadata = StableDict(self._load_meta(self.id))
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metadata[b'name'] = name
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data = msgpack.packb(metadata, unicode_errors='surrogateescape')
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new_id = self.key.id_hash(data)
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self.cache.add_chunk(new_id, data, self.stats)
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self.manifest.archives[name] = {'id': new_id, 'time': metadata[b'time']}
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self.cache.chunk_decref(self.id, self.stats)
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del self.manifest.archives[self.name]
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def delete(self, stats):
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unpacker = msgpack.Unpacker(use_list=False)
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for items_id, data in zip(self.metadata[b'items'], self.repository.get_many(self.metadata[b'items'])):
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unpacker.feed(self.key.decrypt(items_id, data))
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self.cache.chunk_decref(items_id, stats)
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for item in unpacker:
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if b'chunks' in item:
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for chunk_id, size, csize in item[b'chunks']:
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self.cache.chunk_decref(chunk_id, stats)
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self.cache.chunk_decref(self.id, stats)
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del self.manifest.archives[self.name]
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def stat_attrs(self, st, path):
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item = {
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b'mode': st.st_mode,
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b'uid': st.st_uid, b'user': uid2user(st.st_uid),
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b'gid': st.st_gid, b'group': gid2group(st.st_gid),
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b'mtime': int_to_bigint(st_mtime_ns(st))
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}
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if self.numeric_owner:
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item[b'user'] = item[b'group'] = None
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xattrs = xattr.get_all(path, follow_symlinks=False)
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if xattrs:
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item[b'xattrs'] = StableDict(xattrs)
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if has_lchflags and st.st_flags:
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item[b'bsdflags'] = st.st_flags
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acl_get(path, item, st, self.numeric_owner)
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return item
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def process_dir(self, path, st):
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item = {b'path': make_path_safe(path)}
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item.update(self.stat_attrs(st, path))
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self.add_item(item)
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return 'd' # directory
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def process_fifo(self, path, st):
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item = {b'path': make_path_safe(path)}
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item.update(self.stat_attrs(st, path))
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self.add_item(item)
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return 'f' # fifo
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def process_dev(self, path, st):
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item = {b'path': make_path_safe(path), b'rdev': st.st_rdev}
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item.update(self.stat_attrs(st, path))
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self.add_item(item)
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if stat.S_ISCHR(st.st_mode):
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return 'c' # char device
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elif stat.S_ISBLK(st.st_mode):
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return 'b' # block device
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def process_symlink(self, path, st):
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source = os.readlink(path)
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item = {b'path': make_path_safe(path), b'source': source}
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item.update(self.stat_attrs(st, path))
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self.add_item(item)
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return 's' # symlink
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def process_stdin(self, path, cache):
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uid, gid = 0, 0
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fd = sys.stdin.buffer # binary
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chunks = []
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for chunk in self.chunker.chunkify(fd):
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chunks.append(cache.add_chunk(self.key.id_hash(chunk), chunk, self.stats))
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self.stats.nfiles += 1
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item = {
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b'path': path,
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b'chunks': chunks,
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b'mode': 0o100660, # regular file, ug=rw
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b'uid': uid, b'user': uid2user(uid),
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b'gid': gid, b'group': gid2group(gid),
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b'mtime': int_to_bigint(int(time.time()) * 1000000000)
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}
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self.add_item(item)
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def process_file(self, path, st, cache):
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status = None
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safe_path = make_path_safe(path)
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# Is it a hard link?
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if st.st_nlink > 1:
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source = self.hard_links.get((st.st_ino, st.st_dev))
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if (st.st_ino, st.st_dev) in self.hard_links:
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item = self.stat_attrs(st, path)
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item.update({b'path': safe_path, b'source': source})
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self.add_item(item)
|
|
status = 'h' # regular file, hardlink (to already seen inodes)
|
|
return status
|
|
else:
|
|
self.hard_links[st.st_ino, st.st_dev] = safe_path
|
|
path_hash = self.key.id_hash(os.path.join(self.cwd, path).encode('utf-8', 'surrogateescape'))
|
|
ids = cache.file_known_and_unchanged(path_hash, st)
|
|
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
|
|
# Only chunkify the file if needed
|
|
if chunks is None:
|
|
fh = Archive._open_rb(path, st)
|
|
with os.fdopen(fh, 'rb') as fd:
|
|
chunks = []
|
|
for chunk in self.chunker.chunkify(fd, fh):
|
|
chunks.append(cache.add_chunk(self.key.id_hash(chunk), chunk, self.stats))
|
|
cache.memorize_file(path_hash, st, [c[0] for c in chunks])
|
|
status = status or 'M' # regular file, modified (if not 'A' already)
|
|
item = {b'path': safe_path, b'chunks': chunks}
|
|
item.update(self.stat_attrs(st, path))
|
|
self.stats.nfiles += 1
|
|
self.add_item(item)
|
|
return status
|
|
|
|
@staticmethod
|
|
def list_archives(repository, key, manifest, cache=None):
|
|
# expensive! see also Manifest.list_archive_infos.
|
|
for name, info in manifest.archives.items():
|
|
yield Archive(repository, key, manifest, name, cache=cache)
|
|
|
|
@staticmethod
|
|
def _open_rb(path, st):
|
|
flags_normal = os.O_RDONLY | getattr(os, 'O_BINARY', 0)
|
|
flags_noatime = flags_normal | getattr(os, 'NO_ATIME', 0)
|
|
euid = None
|
|
|
|
def open_simple(p, s):
|
|
return os.open(p, flags_normal)
|
|
|
|
def open_noatime(p, s):
|
|
return os.open(p, flags_noatime)
|
|
|
|
def open_noatime_if_owner(p, s):
|
|
if euid == 0 or s.st_uid == euid:
|
|
# we are root or owner of file
|
|
return open_noatime(p, s)
|
|
else:
|
|
return open_simple(p, s)
|
|
|
|
def open_noatime_with_fallback(p, s):
|
|
try:
|
|
fd = os.open(p, flags_noatime)
|
|
except PermissionError:
|
|
# Was this EPERM due to the O_NOATIME flag?
|
|
fd = os.open(p, flags_normal)
|
|
# Yes, it was -- otherwise the above line would have thrown
|
|
# another exception.
|
|
nonlocal euid
|
|
euid = os.geteuid()
|
|
# So in future, let's check whether the file is owned by us
|
|
# before attempting to use O_NOATIME.
|
|
Archive._open_rb = open_noatime_if_owner
|
|
return fd
|
|
|
|
if flags_noatime != flags_normal:
|
|
# Always use O_NOATIME version.
|
|
Archive._open_rb = open_noatime_with_fallback
|
|
else:
|
|
# Always use non-O_NOATIME version.
|
|
Archive._open_rb = open_simple
|
|
return Archive._open_rb(path, st)
|
|
|
|
|
|
class RobustUnpacker():
|
|
"""A restartable/robust version of the streaming msgpack unpacker
|
|
"""
|
|
item_keys = [msgpack.packb(name) for name in ('path', 'mode', 'source', 'chunks', 'rdev', 'xattrs', 'user', 'group', 'uid', 'gid', 'mtime')]
|
|
|
|
def __init__(self, validator):
|
|
super(RobustUnpacker, self).__init__()
|
|
self.validator = validator
|
|
self._buffered_data = []
|
|
self._resync = False
|
|
self._unpacker = msgpack.Unpacker(object_hook=StableDict)
|
|
|
|
def resync(self):
|
|
self._buffered_data = []
|
|
self._resync = True
|
|
|
|
def feed(self, data):
|
|
if self._resync:
|
|
self._buffered_data.append(data)
|
|
else:
|
|
self._unpacker.feed(data)
|
|
|
|
def __iter__(self):
|
|
return self
|
|
|
|
def __next__(self):
|
|
if self._resync:
|
|
data = b''.join(self._buffered_data)
|
|
while self._resync:
|
|
if not data:
|
|
raise StopIteration
|
|
# Abort early if the data does not look like a serialized dict
|
|
if len(data) < 2 or ((data[0] & 0xf0) != 0x80) or ((data[1] & 0xe0) != 0xa0):
|
|
data = data[1:]
|
|
continue
|
|
# Make sure it looks like an item dict
|
|
for pattern in self.item_keys:
|
|
if data[1:].startswith(pattern):
|
|
break
|
|
else:
|
|
data = data[1:]
|
|
continue
|
|
|
|
self._unpacker = msgpack.Unpacker(object_hook=StableDict)
|
|
self._unpacker.feed(data)
|
|
try:
|
|
item = next(self._unpacker)
|
|
if self.validator(item):
|
|
self._resync = False
|
|
return item
|
|
# Ignore exceptions that might be raised when feeding
|
|
# msgpack with invalid data
|
|
except (TypeError, ValueError, StopIteration):
|
|
pass
|
|
data = data[1:]
|
|
else:
|
|
return next(self._unpacker)
|
|
|
|
|
|
class ArchiveChecker:
|
|
|
|
def __init__(self):
|
|
self.error_found = False
|
|
self.possibly_superseded = set()
|
|
self.tmpdir = tempfile.mkdtemp()
|
|
|
|
def __del__(self):
|
|
shutil.rmtree(self.tmpdir)
|
|
|
|
def check(self, repository, repair=False, last=None):
|
|
self.report_progress('Starting archive consistency check...')
|
|
self.repair = repair
|
|
self.repository = repository
|
|
self.init_chunks()
|
|
self.key = self.identify_key(repository)
|
|
if Manifest.manifest_id(repository) not in self.chunks:
|
|
self.manifest = self.rebuild_manifest()
|
|
else:
|
|
self.manifest, _ = Manifest.load(repository, key=self.key)
|
|
self.rebuild_refcounts(last=last)
|
|
if last is None:
|
|
self.verify_chunks()
|
|
else:
|
|
self.report_progress('Orphaned objects check skipped (needs all archives checked)')
|
|
if not self.error_found:
|
|
self.report_progress('Archive consistency check complete, no problems found.')
|
|
return self.repair or not self.error_found
|
|
|
|
def init_chunks(self):
|
|
"""Fetch a list of all object keys from repository
|
|
"""
|
|
# Explicity set the initial hash table capacity to avoid performance issues
|
|
# due to hash table "resonance"
|
|
capacity = int(len(self.repository) * 1.2)
|
|
self.chunks = ChunkIndex(capacity, key_size=self.repository.key_size)
|
|
marker = None
|
|
while True:
|
|
result = self.repository.list(limit=10000, marker=marker)
|
|
if not result:
|
|
break
|
|
marker = result[-1]
|
|
for id_ in result:
|
|
self.chunks[id_] = (0, 0, 0)
|
|
|
|
def report_progress(self, msg, error=False):
|
|
if error:
|
|
self.error_found = True
|
|
print(msg, file=sys.stderr if error else sys.stdout)
|
|
|
|
def identify_key(self, repository):
|
|
cdata = repository.get(next(self.chunks.iteritems())[0])
|
|
return key_factory(repository, cdata)
|
|
|
|
def rebuild_manifest(self):
|
|
"""Rebuild the manifest object if it is missing
|
|
|
|
Iterates through all objects in the repository looking for archive metadata blocks.
|
|
"""
|
|
self.report_progress('Rebuilding missing manifest, this might take some time...', error=True)
|
|
manifest = Manifest(self.key, self.repository)
|
|
for chunk_id, _ in self.chunks.iteritems():
|
|
cdata = self.repository.get(chunk_id)
|
|
data = self.key.decrypt(chunk_id, cdata)
|
|
# Some basic sanity checks of the payload before feeding it into msgpack
|
|
if len(data) < 2 or ((data[0] & 0xf0) != 0x80) or ((data[1] & 0xe0) != 0xa0):
|
|
continue
|
|
if b'cmdline' not in data or b'\xa7version\x01' not in data:
|
|
continue
|
|
try:
|
|
archive = msgpack.unpackb(data)
|
|
# Ignore exceptions that might be raised when feeding
|
|
# msgpack with invalid data
|
|
except (TypeError, ValueError, StopIteration):
|
|
continue
|
|
if isinstance(archive, dict) and b'items' in archive and b'cmdline' in archive:
|
|
self.report_progress('Found archive ' + archive[b'name'].decode('utf-8'), error=True)
|
|
manifest.archives[archive[b'name'].decode('utf-8')] = {b'id': chunk_id, b'time': archive[b'time']}
|
|
self.report_progress('Manifest rebuild complete', error=True)
|
|
return manifest
|
|
|
|
def rebuild_refcounts(self, last=None):
|
|
"""Rebuild object reference counts by walking the metadata
|
|
|
|
Missing and/or incorrect data is repaired when detected
|
|
"""
|
|
# Exclude the manifest from chunks
|
|
del self.chunks[Manifest.manifest_id(self.repository)]
|
|
|
|
def mark_as_possibly_superseded(id_):
|
|
if self.chunks.get(id_, (0,))[0] == 0:
|
|
self.possibly_superseded.add(id_)
|
|
|
|
def add_callback(chunk):
|
|
id_ = self.key.id_hash(chunk)
|
|
cdata = self.key.encrypt(chunk)
|
|
add_reference(id_, len(chunk), len(cdata), cdata)
|
|
return id_
|
|
|
|
def add_reference(id_, size, csize, cdata=None):
|
|
try:
|
|
count, _, _ = self.chunks[id_]
|
|
self.chunks[id_] = count + 1, size, csize
|
|
except KeyError:
|
|
assert cdata is not None
|
|
self.chunks[id_] = 1, size, csize
|
|
if self.repair:
|
|
self.repository.put(id_, cdata)
|
|
|
|
def verify_file_chunks(item):
|
|
"""Verifies that all file chunks are present
|
|
|
|
Missing file chunks will be replaced with new chunks of the same
|
|
length containing all zeros.
|
|
"""
|
|
offset = 0
|
|
chunk_list = []
|
|
for chunk_id, size, csize in item[b'chunks']:
|
|
if chunk_id not in self.chunks:
|
|
# If a file chunk is missing, create an all empty replacement chunk
|
|
self.report_progress('{}: Missing file chunk detected (Byte {}-{})'.format(item[b'path'].decode('utf-8', 'surrogateescape'), offset, offset + size), error=True)
|
|
data = bytes(size)
|
|
chunk_id = self.key.id_hash(data)
|
|
cdata = self.key.encrypt(data)
|
|
csize = len(cdata)
|
|
add_reference(chunk_id, size, csize, cdata)
|
|
else:
|
|
add_reference(chunk_id, size, csize)
|
|
chunk_list.append((chunk_id, size, csize))
|
|
offset += size
|
|
item[b'chunks'] = chunk_list
|
|
|
|
def robust_iterator(archive):
|
|
"""Iterates through all archive items
|
|
|
|
Missing item chunks will be skipped and the msgpack stream will be restarted
|
|
"""
|
|
unpacker = RobustUnpacker(lambda item: isinstance(item, dict) and b'path' in item)
|
|
_state = 0
|
|
|
|
def missing_chunk_detector(chunk_id):
|
|
nonlocal _state
|
|
if _state % 2 != int(chunk_id not in self.chunks):
|
|
_state += 1
|
|
return _state
|
|
|
|
for state, items in groupby(archive[b'items'], missing_chunk_detector):
|
|
items = list(items)
|
|
if state % 2:
|
|
self.report_progress('Archive metadata damage detected', error=True)
|
|
continue
|
|
if state > 0:
|
|
unpacker.resync()
|
|
for chunk_id, cdata in zip(items, repository.get_many(items)):
|
|
unpacker.feed(self.key.decrypt(chunk_id, cdata))
|
|
for item in unpacker:
|
|
yield item
|
|
|
|
repository = cache_if_remote(self.repository)
|
|
num_archives = len(self.manifest.archives)
|
|
archive_items = sorted(self.manifest.archives.items(), reverse=True,
|
|
key=lambda name_info: name_info[1][b'time'])
|
|
end = None if last is None else min(num_archives, last)
|
|
for i, (name, info) in enumerate(archive_items[:end]):
|
|
self.report_progress('Analyzing archive {} ({}/{})'.format(name, num_archives - i, num_archives))
|
|
archive_id = info[b'id']
|
|
if archive_id not in self.chunks:
|
|
self.report_progress('Archive metadata block is missing', error=True)
|
|
del self.manifest.archives[name]
|
|
continue
|
|
mark_as_possibly_superseded(archive_id)
|
|
cdata = self.repository.get(archive_id)
|
|
data = self.key.decrypt(archive_id, cdata)
|
|
archive = StableDict(msgpack.unpackb(data))
|
|
if archive[b'version'] != 1:
|
|
raise Exception('Unknown archive metadata version')
|
|
decode_dict(archive, (b'name', b'hostname', b'username', b'time')) # fixme: argv
|
|
items_buffer = ChunkBuffer(self.key)
|
|
items_buffer.write_chunk = add_callback
|
|
for item in robust_iterator(archive):
|
|
if b'chunks' in item:
|
|
verify_file_chunks(item)
|
|
items_buffer.add(item)
|
|
items_buffer.flush(flush=True)
|
|
for previous_item_id in archive[b'items']:
|
|
mark_as_possibly_superseded(previous_item_id)
|
|
archive[b'items'] = items_buffer.chunks
|
|
data = msgpack.packb(archive, unicode_errors='surrogateescape')
|
|
new_archive_id = self.key.id_hash(data)
|
|
cdata = self.key.encrypt(data)
|
|
add_reference(new_archive_id, len(data), len(cdata), cdata)
|
|
info[b'id'] = new_archive_id
|
|
|
|
def verify_chunks(self):
|
|
unused = set()
|
|
for id_, (count, size, csize) in self.chunks.iteritems():
|
|
if count == 0:
|
|
unused.add(id_)
|
|
orphaned = unused - self.possibly_superseded
|
|
if orphaned:
|
|
self.report_progress('{} orphaned objects found'.format(len(orphaned)), error=True)
|
|
if self.repair:
|
|
for id_ in unused:
|
|
self.repository.delete(id_)
|
|
self.manifest.write()
|
|
self.repository.commit()
|
|
|