mirror of
https://github.com/borgbackup/borg.git
synced 2026-03-21 10:00:06 -04:00
e431d60cc5
# Conflicts: # src/borg/crypto.pyx # src/borg/hashindex.pyx # src/borg/helpers.py # src/borg/platform/__init__.py # src/borg/platform/darwin.pyx # src/borg/platform/freebsd.pyx # src/borg/platform/linux.pyx # src/borg/remote.py
1920 lines
64 KiB
Python
1920 lines
64 KiB
Python
import argparse
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import contextlib
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import grp
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import hashlib
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import logging
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import io
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import os
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import os.path
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import platform
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import pwd
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import re
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import signal
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import socket
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import stat
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import sys
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import textwrap
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import threading
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import time
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import unicodedata
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import uuid
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from binascii import hexlify
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from collections import namedtuple, deque, abc
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from datetime import datetime, timezone, timedelta
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from fnmatch import translate
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from functools import wraps, partial, lru_cache
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from itertools import islice
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from operator import attrgetter
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from string import Formatter
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from shutil import get_terminal_size
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import msgpack
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import msgpack.fallback
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from .logger import create_logger
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logger = create_logger()
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from . import __version__ as borg_version
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from . import __version_tuple__ as borg_version_tuple
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from . import chunker
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from . import crypto
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from . import hashindex
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from . import shellpattern
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from .constants import * # NOQA
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# meta dict, data bytes
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_Chunk = namedtuple('_Chunk', 'meta data')
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def Chunk(data, **meta):
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return _Chunk(meta, data)
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class Error(Exception):
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"""Error base class"""
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# if we raise such an Error and it is only catched by the uppermost
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# exception handler (that exits short after with the given exit_code),
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# it is always a (fatal and abrupt) EXIT_ERROR, never just a warning.
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exit_code = EXIT_ERROR
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# show a traceback?
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traceback = False
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def __init__(self, *args):
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super().__init__(*args)
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self.args = args
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def get_message(self):
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return type(self).__doc__.format(*self.args)
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__str__ = get_message
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class ErrorWithTraceback(Error):
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"""like Error, but show a traceback also"""
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traceback = True
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class IntegrityError(ErrorWithTraceback):
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"""Data integrity error: {}"""
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class ExtensionModuleError(Error):
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"""The Borg binary extension modules do not seem to be properly installed"""
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class NoManifestError(Error):
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"""Repository has no manifest."""
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class PlaceholderError(Error):
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"""Formatting Error: "{}".format({}): {}({})"""
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def check_extension_modules():
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from . import platform, compress, item
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if hashindex.API_VERSION != '1.1_01':
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raise ExtensionModuleError
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if chunker.API_VERSION != '1.1_01':
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raise ExtensionModuleError
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if compress.API_VERSION != '1.1_01':
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raise ExtensionModuleError
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if crypto.API_VERSION != '1.1_01':
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raise ExtensionModuleError
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if platform.API_VERSION != platform.OS_API_VERSION != '1.1_01':
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raise ExtensionModuleError
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if item.API_VERSION != '1.1_01':
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raise ExtensionModuleError
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ArchiveInfo = namedtuple('ArchiveInfo', 'name id ts')
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class Archives(abc.MutableMapping):
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"""
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Nice wrapper around the archives dict, making sure only valid types/values get in
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and we can deal with str keys (and it internally encodes to byte keys) and eiter
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str timestamps or datetime timestamps.
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"""
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def __init__(self):
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# key: encoded archive name, value: dict(b'id': bytes_id, b'time': bytes_iso_ts)
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self._archives = {}
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def __len__(self):
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return len(self._archives)
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def __iter__(self):
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return iter(safe_decode(name) for name in self._archives)
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def __getitem__(self, name):
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assert isinstance(name, str)
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_name = safe_encode(name)
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values = self._archives.get(_name)
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if values is None:
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raise KeyError
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ts = parse_timestamp(values[b'time'].decode('utf-8'))
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return ArchiveInfo(name=name, id=values[b'id'], ts=ts)
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def __setitem__(self, name, info):
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assert isinstance(name, str)
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name = safe_encode(name)
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assert isinstance(info, tuple)
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id, ts = info
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assert isinstance(id, bytes)
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if isinstance(ts, datetime):
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ts = ts.replace(tzinfo=None).isoformat()
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assert isinstance(ts, str)
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ts = ts.encode()
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self._archives[name] = {b'id': id, b'time': ts}
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def __delitem__(self, name):
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assert isinstance(name, str)
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name = safe_encode(name)
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del self._archives[name]
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def list(self, sort_by=(), reverse=False, prefix='', first=None, last=None):
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"""
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Inexpensive Archive.list_archives replacement if we just need .name, .id, .ts
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Returns list of borg.helpers.ArchiveInfo instances.
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sort_by can be a list of sort keys, they are applied in reverse order.
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"""
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if isinstance(sort_by, (str, bytes)):
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raise TypeError('sort_by must be a sequence of str')
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archives = [x for x in self.values() if x.name.startswith(prefix)]
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for sortkey in reversed(sort_by):
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archives.sort(key=attrgetter(sortkey))
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if reverse or last:
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archives.reverse()
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n = first or last or len(archives)
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return archives[:n]
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def list_considering(self, args):
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"""
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get a list of archives, considering --first/last/prefix/sort cmdline args
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"""
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if args.location.archive:
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raise Error('The options --first, --last and --prefix can only be used on repository targets.')
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return self.list(sort_by=args.sort_by.split(','), prefix=args.prefix, first=args.first, last=args.last)
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def set_raw_dict(self, d):
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"""set the dict we get from the msgpack unpacker"""
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for k, v in d.items():
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assert isinstance(k, bytes)
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assert isinstance(v, dict) and b'id' in v and b'time' in v
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self._archives[k] = v
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def get_raw_dict(self):
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"""get the dict we can give to the msgpack packer"""
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return self._archives
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class Manifest:
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MANIFEST_ID = b'\0' * 32
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def __init__(self, key, repository, item_keys=None):
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self.archives = Archives()
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self.config = {}
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self.key = key
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self.repository = repository
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self.item_keys = frozenset(item_keys) if item_keys is not None else ITEM_KEYS
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self.tam_verified = False
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@property
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def id_str(self):
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return bin_to_hex(self.id)
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@classmethod
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def load(cls, repository, key=None, force_tam_not_required=False):
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from .item import ManifestItem
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from .key import key_factory, tam_required_file, tam_required
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from .repository import Repository
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try:
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cdata = repository.get(cls.MANIFEST_ID)
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except Repository.ObjectNotFound:
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raise NoManifestError
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if not key:
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key = key_factory(repository, cdata)
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manifest = cls(key, repository)
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data = key.decrypt(None, cdata).data
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manifest_dict, manifest.tam_verified = key.unpack_and_verify_manifest(data, force_tam_not_required=force_tam_not_required)
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m = ManifestItem(internal_dict=manifest_dict)
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manifest.id = key.id_hash(data)
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if m.get('version') != 1:
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raise ValueError('Invalid manifest version')
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manifest.archives.set_raw_dict(m.archives)
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manifest.timestamp = m.get('timestamp')
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manifest.config = m.config
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# valid item keys are whatever is known in the repo or every key we know
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manifest.item_keys = ITEM_KEYS | frozenset(key.decode() for key in m.get('item_keys', []))
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if manifest.tam_verified:
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manifest_required = manifest.config.get(b'tam_required', False)
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security_required = tam_required(repository)
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if manifest_required and not security_required:
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logger.debug('Manifest is TAM verified and says TAM is required, updating security database...')
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file = tam_required_file(repository)
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open(file, 'w').close()
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if not manifest_required and security_required:
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logger.debug('Manifest is TAM verified and says TAM is *not* required, updating security database...')
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os.unlink(tam_required_file(repository))
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return manifest, key
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def write(self):
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from .item import ManifestItem
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if self.key.tam_required:
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self.config[b'tam_required'] = True
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self.timestamp = datetime.utcnow().isoformat()
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manifest = ManifestItem(
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version=1,
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archives=StableDict(self.archives.get_raw_dict()),
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timestamp=self.timestamp,
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config=StableDict(self.config),
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item_keys=tuple(sorted(self.item_keys)),
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)
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self.tam_verified = True
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data = self.key.pack_and_authenticate_metadata(manifest.as_dict())
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self.id = self.key.id_hash(data)
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self.repository.put(self.MANIFEST_ID, self.key.encrypt(Chunk(data, compression={'name': 'none'})))
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def prune_within(archives, within):
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multiplier = {'H': 1, 'd': 24, 'w': 24 * 7, 'm': 24 * 31, 'y': 24 * 365}
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try:
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hours = int(within[:-1]) * multiplier[within[-1]]
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except (KeyError, ValueError):
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# I don't like how this displays the original exception too:
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raise argparse.ArgumentTypeError('Unable to parse --within option: "%s"' % within)
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if hours <= 0:
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raise argparse.ArgumentTypeError('Number specified using --within option must be positive')
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target = datetime.now(timezone.utc) - timedelta(seconds=hours * 3600)
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return [a for a in archives if a.ts > target]
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def prune_split(archives, pattern, n, skip=[]):
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last = None
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keep = []
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if n == 0:
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return keep
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for a in sorted(archives, key=attrgetter('ts'), reverse=True):
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period = to_localtime(a.ts).strftime(pattern)
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if period != last:
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last = period
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if a not in skip:
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keep.append(a)
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if len(keep) == n:
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break
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return keep
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def get_home_dir():
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"""Get user's home directory while preferring a possibly set HOME
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environment variable
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"""
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# os.path.expanduser() behaves differently for '~' and '~someuser' as
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# parameters: when called with an explicit username, the possibly set
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# environment variable HOME is no longer respected. So we have to check if
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# it is set and only expand the user's home directory if HOME is unset.
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if os.environ.get('HOME', ''):
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return os.environ.get('HOME')
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else:
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return os.path.expanduser('~%s' % os.environ.get('USER', ''))
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def get_keys_dir():
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"""Determine where to repository keys and cache"""
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xdg_config = os.environ.get('XDG_CONFIG_HOME', os.path.join(get_home_dir(), '.config'))
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keys_dir = os.environ.get('BORG_KEYS_DIR', os.path.join(xdg_config, 'borg', 'keys'))
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if not os.path.exists(keys_dir):
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os.makedirs(keys_dir)
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os.chmod(keys_dir, stat.S_IRWXU)
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return keys_dir
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def get_security_dir(repository_id=None):
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"""Determine where to store local security information."""
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xdg_config = os.environ.get('XDG_CONFIG_HOME', os.path.join(get_home_dir(), '.config'))
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security_dir = os.environ.get('BORG_SECURITY_DIR', os.path.join(xdg_config, 'borg', 'security'))
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if repository_id:
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security_dir = os.path.join(security_dir, repository_id)
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if not os.path.exists(security_dir):
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os.makedirs(security_dir)
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os.chmod(security_dir, stat.S_IRWXU)
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return security_dir
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def get_cache_dir():
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"""Determine where to repository keys and cache"""
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xdg_cache = os.environ.get('XDG_CACHE_HOME', os.path.join(get_home_dir(), '.cache'))
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cache_dir = os.environ.get('BORG_CACHE_DIR', os.path.join(xdg_cache, 'borg'))
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if not os.path.exists(cache_dir):
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os.makedirs(cache_dir)
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os.chmod(cache_dir, stat.S_IRWXU)
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with open(os.path.join(cache_dir, CACHE_TAG_NAME), 'wb') as fd:
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fd.write(CACHE_TAG_CONTENTS)
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fd.write(textwrap.dedent("""
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# This file is a cache directory tag created by Borg.
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# For information about cache directory tags, see:
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# http://www.brynosaurus.com/cachedir/
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""").encode('ascii'))
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return cache_dir
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def to_localtime(ts):
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"""Convert datetime object from UTC to local time zone"""
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return datetime(*time.localtime((ts - datetime(1970, 1, 1, tzinfo=timezone.utc)).total_seconds())[:6])
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def parse_timestamp(timestamp):
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"""Parse a ISO 8601 timestamp string"""
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if '.' in timestamp: # microseconds might not be present
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return datetime.strptime(timestamp, '%Y-%m-%dT%H:%M:%S.%f').replace(tzinfo=timezone.utc)
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else:
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return datetime.strptime(timestamp, '%Y-%m-%dT%H:%M:%S').replace(tzinfo=timezone.utc)
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def load_excludes(fh):
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"""Load and parse exclude patterns from file object. Lines empty or starting with '#' after stripping whitespace on
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both line ends are ignored.
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"""
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return [parse_pattern(pattern) for pattern in clean_lines(fh)]
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def update_excludes(args):
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"""Merge exclude patterns from files with those on command line."""
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if hasattr(args, 'exclude_files') and args.exclude_files:
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if not hasattr(args, 'excludes') or args.excludes is None:
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args.excludes = []
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for file in args.exclude_files:
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args.excludes += load_excludes(file)
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file.close()
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class PatternMatcher:
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def __init__(self, fallback=None):
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self._items = []
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# Value to return from match function when none of the patterns match.
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self.fallback = fallback
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def empty(self):
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return not len(self._items)
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def add(self, patterns, value):
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"""Add list of patterns to internal list. The given value is returned from the match function when one of the
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given patterns matches.
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"""
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self._items.extend((i, value) for i in patterns)
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def match(self, path):
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for (pattern, value) in self._items:
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if pattern.match(path):
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return value
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return self.fallback
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def normalized(func):
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""" Decorator for the Pattern match methods, returning a wrapper that
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normalizes OSX paths to match the normalized pattern on OSX, and
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returning the original method on other platforms"""
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@wraps(func)
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def normalize_wrapper(self, path):
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return func(self, unicodedata.normalize("NFD", path))
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if sys.platform in ('darwin',):
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# HFS+ converts paths to a canonical form, so users shouldn't be
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# required to enter an exact match
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return normalize_wrapper
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else:
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# Windows and Unix filesystems allow different forms, so users
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# always have to enter an exact match
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return func
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class PatternBase:
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"""Shared logic for inclusion/exclusion patterns.
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"""
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PREFIX = NotImplemented
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def __init__(self, pattern):
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self.pattern_orig = pattern
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self.match_count = 0
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if sys.platform in ('darwin',):
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pattern = unicodedata.normalize("NFD", pattern)
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self._prepare(pattern)
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@normalized
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def match(self, path):
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matches = self._match(path)
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if matches:
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self.match_count += 1
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return matches
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def __repr__(self):
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return '%s(%s)' % (type(self), self.pattern)
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def __str__(self):
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return self.pattern_orig
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def _prepare(self, pattern):
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raise NotImplementedError
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def _match(self, path):
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raise NotImplementedError
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# For PathPrefixPattern, FnmatchPattern and ShellPattern, we require that the pattern either match the whole path
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# or an initial segment of the path up to but not including a path separator. To unify the two cases, we add a path
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# separator to the end of the path before matching.
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class PathPrefixPattern(PatternBase):
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"""Literal files or directories listed on the command line
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for some operations (e.g. extract, but not create).
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If a directory is specified, all paths that start with that
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path match as well. A trailing slash makes no difference.
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"""
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PREFIX = "pp"
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def _prepare(self, pattern):
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self.pattern = os.path.normpath(pattern).rstrip(os.path.sep) + os.path.sep
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def _match(self, path):
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return (path + os.path.sep).startswith(self.pattern)
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class FnmatchPattern(PatternBase):
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"""Shell glob patterns to exclude. A trailing slash means to
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exclude the contents of a directory, but not the directory itself.
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"""
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PREFIX = "fm"
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def _prepare(self, pattern):
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if pattern.endswith(os.path.sep):
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pattern = os.path.normpath(pattern).rstrip(os.path.sep) + os.path.sep + '*' + os.path.sep
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else:
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pattern = os.path.normpath(pattern) + os.path.sep + '*'
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self.pattern = pattern
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# fnmatch and re.match both cache compiled regular expressions.
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# Nevertheless, this is about 10 times faster.
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self.regex = re.compile(translate(self.pattern))
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def _match(self, path):
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return (self.regex.match(path + os.path.sep) is not None)
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class ShellPattern(PatternBase):
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"""Shell glob patterns to exclude. A trailing slash means to
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exclude the contents of a directory, but not the directory itself.
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"""
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PREFIX = "sh"
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def _prepare(self, pattern):
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sep = os.path.sep
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if pattern.endswith(sep):
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pattern = os.path.normpath(pattern).rstrip(sep) + sep + "**" + sep + "*" + sep
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else:
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pattern = os.path.normpath(pattern) + sep + "**" + sep + "*"
|
|
|
|
self.pattern = pattern
|
|
self.regex = re.compile(shellpattern.translate(self.pattern))
|
|
|
|
def _match(self, path):
|
|
return (self.regex.match(path + os.path.sep) is not None)
|
|
|
|
|
|
class RegexPattern(PatternBase):
|
|
"""Regular expression to exclude.
|
|
"""
|
|
PREFIX = "re"
|
|
|
|
def _prepare(self, pattern):
|
|
self.pattern = pattern
|
|
self.regex = re.compile(pattern)
|
|
|
|
def _match(self, path):
|
|
# Normalize path separators
|
|
if os.path.sep != '/':
|
|
path = path.replace(os.path.sep, '/')
|
|
|
|
return (self.regex.search(path) is not None)
|
|
|
|
|
|
_PATTERN_STYLES = set([
|
|
FnmatchPattern,
|
|
PathPrefixPattern,
|
|
RegexPattern,
|
|
ShellPattern,
|
|
])
|
|
|
|
_PATTERN_STYLE_BY_PREFIX = dict((i.PREFIX, i) for i in _PATTERN_STYLES)
|
|
|
|
|
|
def parse_pattern(pattern, fallback=FnmatchPattern):
|
|
"""Read pattern from string and return an instance of the appropriate implementation class.
|
|
"""
|
|
if len(pattern) > 2 and pattern[2] == ":" and pattern[:2].isalnum():
|
|
(style, pattern) = (pattern[:2], pattern[3:])
|
|
|
|
cls = _PATTERN_STYLE_BY_PREFIX.get(style, None)
|
|
|
|
if cls is None:
|
|
raise ValueError("Unknown pattern style: {}".format(style))
|
|
else:
|
|
cls = fallback
|
|
|
|
return cls(pattern)
|
|
|
|
|
|
def timestamp(s):
|
|
"""Convert a --timestamp=s argument to a datetime object"""
|
|
try:
|
|
# is it pointing to a file / directory?
|
|
ts = os.stat(s).st_mtime
|
|
return datetime.utcfromtimestamp(ts)
|
|
except OSError:
|
|
# didn't work, try parsing as timestamp. UTC, no TZ, no microsecs support.
|
|
for format in ('%Y-%m-%dT%H:%M:%SZ', '%Y-%m-%dT%H:%M:%S+00:00',
|
|
'%Y-%m-%dT%H:%M:%S', '%Y-%m-%d %H:%M:%S',
|
|
'%Y-%m-%dT%H:%M', '%Y-%m-%d %H:%M',
|
|
'%Y-%m-%d', '%Y-%j',
|
|
):
|
|
try:
|
|
return datetime.strptime(s, format)
|
|
except ValueError:
|
|
continue
|
|
raise ValueError
|
|
|
|
|
|
def ChunkerParams(s):
|
|
if s.strip().lower() == "default":
|
|
return CHUNKER_PARAMS
|
|
chunk_min, chunk_max, chunk_mask, window_size = s.split(',')
|
|
if int(chunk_max) > 23:
|
|
raise ValueError('max. chunk size exponent must not be more than 23 (2^23 = 8MiB max. chunk size)')
|
|
return int(chunk_min), int(chunk_max), int(chunk_mask), int(window_size)
|
|
|
|
|
|
def CompressionSpec(s):
|
|
values = s.split(',')
|
|
count = len(values)
|
|
if count < 1:
|
|
raise ValueError
|
|
# --compression algo[,level]
|
|
name = values[0]
|
|
if name in ('none', 'lz4', ):
|
|
return dict(name=name)
|
|
if name in ('zlib', 'lzma', ):
|
|
if count < 2:
|
|
level = 6 # default compression level in py stdlib
|
|
elif count == 2:
|
|
level = int(values[1])
|
|
if not 0 <= level <= 9:
|
|
raise ValueError
|
|
else:
|
|
raise ValueError
|
|
return dict(name=name, level=level)
|
|
if name == 'auto':
|
|
if 2 <= count <= 3:
|
|
compression = ','.join(values[1:])
|
|
else:
|
|
raise ValueError
|
|
return dict(name=name, spec=CompressionSpec(compression))
|
|
raise ValueError
|
|
|
|
|
|
def dir_is_cachedir(path):
|
|
"""Determines whether the specified path is a cache directory (and
|
|
therefore should potentially be excluded from the backup) according to
|
|
the CACHEDIR.TAG protocol
|
|
(http://www.brynosaurus.com/cachedir/spec.html).
|
|
"""
|
|
|
|
tag_path = os.path.join(path, CACHE_TAG_NAME)
|
|
try:
|
|
if os.path.exists(tag_path):
|
|
with open(tag_path, 'rb') as tag_file:
|
|
tag_data = tag_file.read(len(CACHE_TAG_CONTENTS))
|
|
if tag_data == CACHE_TAG_CONTENTS:
|
|
return True
|
|
except OSError:
|
|
pass
|
|
return False
|
|
|
|
|
|
def dir_is_tagged(path, exclude_caches, exclude_if_present):
|
|
"""Determines whether the specified path is excluded by being a cache
|
|
directory or containing user-specified tag files. Returns a list of the
|
|
paths of the tag files (either CACHEDIR.TAG or the matching
|
|
user-specified files).
|
|
"""
|
|
tag_paths = []
|
|
if exclude_caches and dir_is_cachedir(path):
|
|
tag_paths.append(os.path.join(path, CACHE_TAG_NAME))
|
|
if exclude_if_present is not None:
|
|
for tag in exclude_if_present:
|
|
tag_path = os.path.join(path, tag)
|
|
if os.path.isfile(tag_path):
|
|
tag_paths.append(tag_path)
|
|
return tag_paths
|
|
|
|
|
|
def partial_format(format, mapping):
|
|
"""
|
|
Apply format.format_map(mapping) while preserving unknown keys
|
|
|
|
Does not support attribute access, indexing and ![rsa] conversions
|
|
"""
|
|
for key, value in mapping.items():
|
|
key = re.escape(key)
|
|
format = re.sub(r'(?<!\{)((\{%s\})|(\{%s:[^\}]*\}))' % (key, key),
|
|
lambda match: match.group(1).format_map(mapping),
|
|
format)
|
|
return format
|
|
|
|
|
|
class DatetimeWrapper:
|
|
def __init__(self, dt):
|
|
self.dt = dt
|
|
|
|
def __format__(self, format_spec):
|
|
if format_spec == '':
|
|
format_spec = '%Y-%m-%dT%H:%M:%S'
|
|
return self.dt.__format__(format_spec)
|
|
|
|
|
|
def format_line(format, data):
|
|
try:
|
|
return format.format(**data)
|
|
except Exception as e:
|
|
raise PlaceholderError(format, data, e.__class__.__name__, str(e))
|
|
|
|
|
|
def replace_placeholders(text):
|
|
"""Replace placeholders in text with their values."""
|
|
current_time = datetime.now()
|
|
data = {
|
|
'pid': os.getpid(),
|
|
'fqdn': socket.getfqdn(),
|
|
'hostname': socket.gethostname(),
|
|
'now': DatetimeWrapper(current_time.now()),
|
|
'utcnow': DatetimeWrapper(current_time.utcnow()),
|
|
'user': uid2user(os.getuid(), os.getuid()),
|
|
'uuid4': str(uuid.uuid4()),
|
|
'borgversion': borg_version,
|
|
'borgmajor': '%d' % borg_version_tuple[:1],
|
|
'borgminor': '%d.%d' % borg_version_tuple[:2],
|
|
'borgpatch': '%d.%d.%d' % borg_version_tuple[:3],
|
|
}
|
|
return format_line(text, data)
|
|
|
|
|
|
PrefixSpec = replace_placeholders
|
|
|
|
|
|
HUMAN_SORT_KEYS = ['timestamp'] + list(ArchiveInfo._fields)
|
|
HUMAN_SORT_KEYS.remove('ts')
|
|
|
|
|
|
def SortBySpec(text):
|
|
for token in text.split(','):
|
|
if token not in HUMAN_SORT_KEYS:
|
|
raise ValueError('Invalid sort key: %s' % token)
|
|
return text.replace('timestamp', 'ts')
|
|
|
|
|
|
def safe_timestamp(item_timestamp_ns):
|
|
try:
|
|
return datetime.fromtimestamp(item_timestamp_ns / 1e9)
|
|
except OverflowError:
|
|
# likely a broken file time and datetime did not want to go beyond year 9999
|
|
return datetime(9999, 12, 31, 23, 59, 59)
|
|
|
|
|
|
def format_time(t):
|
|
"""use ISO-8601 date and time format
|
|
"""
|
|
return t.strftime('%a, %Y-%m-%d %H:%M:%S')
|
|
|
|
|
|
def format_timedelta(td):
|
|
"""Format timedelta in a human friendly format
|
|
"""
|
|
ts = td.total_seconds()
|
|
s = ts % 60
|
|
m = int(ts / 60) % 60
|
|
h = int(ts / 3600) % 24
|
|
txt = '%.2f seconds' % s
|
|
if m:
|
|
txt = '%d minutes %s' % (m, txt)
|
|
if h:
|
|
txt = '%d hours %s' % (h, txt)
|
|
if td.days:
|
|
txt = '%d days %s' % (td.days, txt)
|
|
return txt
|
|
|
|
|
|
def format_file_size(v, precision=2, sign=False):
|
|
"""Format file size into a human friendly format
|
|
"""
|
|
return sizeof_fmt_decimal(v, suffix='B', sep=' ', precision=precision, sign=sign)
|
|
|
|
|
|
def parse_file_size(s):
|
|
"""Return int from file size (1234, 55G, 1.7T)."""
|
|
if not s:
|
|
return int(s) # will raise
|
|
suffix = s[-1]
|
|
power = 1000
|
|
try:
|
|
factor = {
|
|
'K': power,
|
|
'M': power**2,
|
|
'G': power**3,
|
|
'T': power**4,
|
|
'P': power**5,
|
|
}[suffix]
|
|
s = s[:-1]
|
|
except KeyError:
|
|
factor = 1
|
|
return int(float(s) * factor)
|
|
|
|
|
|
def sizeof_fmt(num, suffix='B', units=None, power=None, sep='', precision=2, sign=False):
|
|
prefix = '+' if sign and num > 0 else ''
|
|
|
|
for unit in units[:-1]:
|
|
if abs(round(num, precision)) < power:
|
|
if isinstance(num, int):
|
|
return "{}{}{}{}{}".format(prefix, num, sep, unit, suffix)
|
|
else:
|
|
return "{}{:3.{}f}{}{}{}".format(prefix, num, precision, sep, unit, suffix)
|
|
num /= float(power)
|
|
return "{}{:.{}f}{}{}{}".format(prefix, num, precision, sep, units[-1], suffix)
|
|
|
|
|
|
def sizeof_fmt_iec(num, suffix='B', sep='', precision=2, sign=False):
|
|
return sizeof_fmt(num, suffix=suffix, sep=sep, precision=precision, sign=sign,
|
|
units=['', 'Ki', 'Mi', 'Gi', 'Ti', 'Pi', 'Ei', 'Zi', 'Yi'], power=1024)
|
|
|
|
|
|
def sizeof_fmt_decimal(num, suffix='B', sep='', precision=2, sign=False):
|
|
return sizeof_fmt(num, suffix=suffix, sep=sep, precision=precision, sign=sign,
|
|
units=['', 'k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y'], power=1000)
|
|
|
|
|
|
def format_archive(archive):
|
|
return '%-36s %s [%s]' % (
|
|
archive.name,
|
|
format_time(to_localtime(archive.ts)),
|
|
bin_to_hex(archive.id),
|
|
)
|
|
|
|
|
|
class Buffer:
|
|
"""
|
|
provide a thread-local buffer
|
|
"""
|
|
|
|
class MemoryLimitExceeded(Error, OSError):
|
|
"""Requested buffer size {} is above the limit of {}."""
|
|
|
|
def __init__(self, allocator, size=4096, limit=None):
|
|
"""
|
|
Initialize the buffer: use allocator(size) call to allocate a buffer.
|
|
Optionally, set the upper <limit> for the buffer size.
|
|
"""
|
|
assert callable(allocator), 'must give alloc(size) function as first param'
|
|
assert limit is None or size <= limit, 'initial size must be <= limit'
|
|
self._thread_local = threading.local()
|
|
self.allocator = allocator
|
|
self.limit = limit
|
|
self.resize(size, init=True)
|
|
|
|
def __len__(self):
|
|
return len(self._thread_local.buffer)
|
|
|
|
def resize(self, size, init=False):
|
|
"""
|
|
resize the buffer - to avoid frequent reallocation, we usually always grow (if needed).
|
|
giving init=True it is possible to first-time initialize or shrink the buffer.
|
|
if a buffer size beyond the limit is requested, raise Buffer.MemoryLimitExceeded (OSError).
|
|
"""
|
|
size = int(size)
|
|
if self.limit is not None and size > self.limit:
|
|
raise Buffer.MemoryLimitExceeded(size, self.limit)
|
|
if init or len(self) < size:
|
|
self._thread_local.buffer = self.allocator(size)
|
|
|
|
def get(self, size=None, init=False):
|
|
"""
|
|
return a buffer of at least the requested size (None: any current size).
|
|
init=True can be given to trigger shrinking of the buffer to the given size.
|
|
"""
|
|
if size is not None:
|
|
self.resize(size, init)
|
|
return self._thread_local.buffer
|
|
|
|
|
|
@lru_cache(maxsize=None)
|
|
def uid2user(uid, default=None):
|
|
try:
|
|
return pwd.getpwuid(uid).pw_name
|
|
except KeyError:
|
|
return default
|
|
|
|
|
|
@lru_cache(maxsize=None)
|
|
def user2uid(user, default=None):
|
|
try:
|
|
return user and pwd.getpwnam(user).pw_uid
|
|
except KeyError:
|
|
return default
|
|
|
|
|
|
@lru_cache(maxsize=None)
|
|
def gid2group(gid, default=None):
|
|
try:
|
|
return grp.getgrgid(gid).gr_name
|
|
except KeyError:
|
|
return default
|
|
|
|
|
|
@lru_cache(maxsize=None)
|
|
def group2gid(group, default=None):
|
|
try:
|
|
return group and grp.getgrnam(group).gr_gid
|
|
except KeyError:
|
|
return default
|
|
|
|
|
|
def posix_acl_use_stored_uid_gid(acl):
|
|
"""Replace the user/group field with the stored uid/gid
|
|
"""
|
|
entries = []
|
|
for entry in safe_decode(acl).split('\n'):
|
|
if entry:
|
|
fields = entry.split(':')
|
|
if len(fields) == 4:
|
|
entries.append(':'.join([fields[0], fields[3], fields[2]]))
|
|
else:
|
|
entries.append(entry)
|
|
return safe_encode('\n'.join(entries))
|
|
|
|
|
|
def safe_decode(s, coding='utf-8', errors='surrogateescape'):
|
|
"""decode bytes to str, with round-tripping "invalid" bytes"""
|
|
if s is None:
|
|
return None
|
|
return s.decode(coding, errors)
|
|
|
|
|
|
def safe_encode(s, coding='utf-8', errors='surrogateescape'):
|
|
"""encode str to bytes, with round-tripping "invalid" bytes"""
|
|
if s is None:
|
|
return None
|
|
return s.encode(coding, errors)
|
|
|
|
|
|
def bin_to_hex(binary):
|
|
return hexlify(binary).decode('ascii')
|
|
|
|
|
|
class Location:
|
|
"""Object representing a repository / archive location
|
|
"""
|
|
proto = user = host = port = path = archive = None
|
|
|
|
# user must not contain "@", ":" or "/".
|
|
# Quoting adduser error message:
|
|
# "To avoid problems, the username should consist only of letters, digits,
|
|
# underscores, periods, at signs and dashes, and not start with a dash
|
|
# (as defined by IEEE Std 1003.1-2001)."
|
|
# We use "@" as separator between username and hostname, so we must
|
|
# disallow it within the pure username part.
|
|
optional_user_re = r"""
|
|
(?:(?P<user>[^@:/]+)@)?
|
|
"""
|
|
|
|
# path must not contain :: (it ends at :: or string end), but may contain single colons.
|
|
# to avoid ambiguities with other regexes, it must also not start with ":".
|
|
path_re = r"""
|
|
(?!:) # not starting with ":"
|
|
(?P<path>([^:]|(:(?!:)))+) # any chars, but no "::"
|
|
"""
|
|
# optional ::archive_name at the end, archive name must not contain "/".
|
|
# borg mount's FUSE filesystem creates one level of directories from
|
|
# the archive names and of course "/" is not valid in a directory name.
|
|
optional_archive_re = r"""
|
|
(?:
|
|
:: # "::" as separator
|
|
(?P<archive>[^/]+) # archive name must not contain "/"
|
|
)?$""" # must match until the end
|
|
|
|
# regexes for misc. kinds of supported location specifiers:
|
|
ssh_re = re.compile(r"""
|
|
(?P<proto>ssh):// # ssh://
|
|
""" + optional_user_re + r""" # user@ (optional)
|
|
(?P<host>[^:/]+)(?::(?P<port>\d+))? # host or host:port
|
|
""" + path_re + optional_archive_re, re.VERBOSE) # path or path::archive
|
|
|
|
file_re = re.compile(r"""
|
|
(?P<proto>file):// # file://
|
|
""" + path_re + optional_archive_re, re.VERBOSE) # path or path::archive
|
|
|
|
# note: scp_re is also use for local pathes
|
|
scp_re = re.compile(r"""
|
|
(
|
|
""" + optional_user_re + r""" # user@ (optional)
|
|
(?P<host>[^:/]+): # host: (don't match / in host to disambiguate from file:)
|
|
)? # user@host: part is optional
|
|
""" + path_re + optional_archive_re, re.VERBOSE) # path with optional archive
|
|
|
|
# get the repo from BORG_REPO env and the optional archive from param.
|
|
# if the syntax requires giving REPOSITORY (see "borg mount"),
|
|
# use "::" to let it use the env var.
|
|
# if REPOSITORY argument is optional, it'll automatically use the env.
|
|
env_re = re.compile(r""" # the repo part is fetched from BORG_REPO
|
|
(?:::$) # just "::" is ok (when a pos. arg is required, no archive)
|
|
| # or
|
|
""" + optional_archive_re, re.VERBOSE) # archive name (optional, may be empty)
|
|
|
|
def __init__(self, text=''):
|
|
self.orig = text
|
|
if not self.parse(self.orig):
|
|
raise ValueError
|
|
|
|
def parse(self, text):
|
|
text = replace_placeholders(text)
|
|
valid = self._parse(text)
|
|
if valid:
|
|
return True
|
|
m = self.env_re.match(text)
|
|
if not m:
|
|
return False
|
|
repo = os.environ.get('BORG_REPO')
|
|
if repo is None:
|
|
return False
|
|
valid = self._parse(repo)
|
|
if not valid:
|
|
return False
|
|
self.archive = m.group('archive')
|
|
return True
|
|
|
|
def _parse(self, text):
|
|
def normpath_special(p):
|
|
# avoid that normpath strips away our relative path hack and even makes p absolute
|
|
relative = p.startswith('/./')
|
|
p = os.path.normpath(p)
|
|
return ('/.' + p) if relative else p
|
|
|
|
m = self.ssh_re.match(text)
|
|
if m:
|
|
self.proto = m.group('proto')
|
|
self.user = m.group('user')
|
|
self.host = m.group('host')
|
|
self.port = m.group('port') and int(m.group('port')) or None
|
|
self.path = normpath_special(m.group('path'))
|
|
self.archive = m.group('archive')
|
|
return True
|
|
m = self.file_re.match(text)
|
|
if m:
|
|
self.proto = m.group('proto')
|
|
self.path = normpath_special(m.group('path'))
|
|
self.archive = m.group('archive')
|
|
return True
|
|
m = self.scp_re.match(text)
|
|
if m:
|
|
self.user = m.group('user')
|
|
self.host = m.group('host')
|
|
self.path = normpath_special(m.group('path'))
|
|
self.archive = m.group('archive')
|
|
self.proto = self.host and 'ssh' or 'file'
|
|
return True
|
|
return False
|
|
|
|
def __str__(self):
|
|
items = [
|
|
'proto=%r' % self.proto,
|
|
'user=%r' % self.user,
|
|
'host=%r' % self.host,
|
|
'port=%r' % self.port,
|
|
'path=%r' % self.path,
|
|
'archive=%r' % self.archive,
|
|
]
|
|
return ', '.join(items)
|
|
|
|
def to_key_filename(self):
|
|
name = re.sub('[^\w]', '_', self.path).strip('_')
|
|
if self.proto != 'file':
|
|
name = self.host + '__' + name
|
|
return os.path.join(get_keys_dir(), name)
|
|
|
|
def __repr__(self):
|
|
return "Location(%s)" % self
|
|
|
|
def canonical_path(self):
|
|
if self.proto == 'file':
|
|
return self.path
|
|
else:
|
|
if self.path and self.path.startswith('~'):
|
|
path = '/' + self.path # /~/x = path x relative to home dir
|
|
elif self.path and not self.path.startswith('/'):
|
|
path = '/./' + self.path # /./x = path x relative to cwd
|
|
else:
|
|
path = self.path
|
|
return 'ssh://{}{}{}{}'.format('{}@'.format(self.user) if self.user else '',
|
|
self.host,
|
|
':{}'.format(self.port) if self.port else '',
|
|
path)
|
|
|
|
|
|
def location_validator(archive=None):
|
|
def validator(text):
|
|
try:
|
|
loc = Location(text)
|
|
except ValueError:
|
|
raise argparse.ArgumentTypeError('Invalid location format: "%s"' % text) from None
|
|
if archive is True and not loc.archive:
|
|
raise argparse.ArgumentTypeError('"%s": No archive specified' % text)
|
|
elif archive is False and loc.archive:
|
|
raise argparse.ArgumentTypeError('"%s" No archive can be specified' % text)
|
|
return loc
|
|
return validator
|
|
|
|
|
|
def archivename_validator():
|
|
def validator(text):
|
|
if '/' in text or '::' in text or not text:
|
|
raise argparse.ArgumentTypeError('Invalid repository name: "%s"' % text)
|
|
return text
|
|
return validator
|
|
|
|
|
|
def decode_dict(d, keys, encoding='utf-8', errors='surrogateescape'):
|
|
for key in keys:
|
|
if isinstance(d.get(key), bytes):
|
|
d[key] = d[key].decode(encoding, errors)
|
|
return d
|
|
|
|
|
|
def remove_surrogates(s, errors='replace'):
|
|
"""Replace surrogates generated by fsdecode with '?'
|
|
"""
|
|
return s.encode('utf-8', errors).decode('utf-8')
|
|
|
|
|
|
_safe_re = re.compile(r'^((\.\.)?/+)+')
|
|
|
|
|
|
def make_path_safe(path):
|
|
"""Make path safe by making it relative and local
|
|
"""
|
|
return _safe_re.sub('', path) or '.'
|
|
|
|
|
|
def daemonize():
|
|
"""Detach process from controlling terminal and run in background
|
|
"""
|
|
pid = os.fork()
|
|
if pid:
|
|
os._exit(0)
|
|
os.setsid()
|
|
pid = os.fork()
|
|
if pid:
|
|
os._exit(0)
|
|
os.chdir('/')
|
|
os.close(0)
|
|
os.close(1)
|
|
os.close(2)
|
|
fd = os.open(os.devnull, os.O_RDWR)
|
|
os.dup2(fd, 0)
|
|
os.dup2(fd, 1)
|
|
os.dup2(fd, 2)
|
|
|
|
|
|
class StableDict(dict):
|
|
"""A dict subclass with stable items() ordering"""
|
|
def items(self):
|
|
return sorted(super().items())
|
|
|
|
|
|
def is_slow_msgpack():
|
|
return msgpack.Packer is msgpack.fallback.Packer
|
|
|
|
|
|
FALSISH = ('No', 'NO', 'no', 'N', 'n', '0', )
|
|
TRUISH = ('Yes', 'YES', 'yes', 'Y', 'y', '1', )
|
|
DEFAULTISH = ('Default', 'DEFAULT', 'default', 'D', 'd', '', )
|
|
|
|
|
|
def yes(msg=None, false_msg=None, true_msg=None, default_msg=None,
|
|
retry_msg=None, invalid_msg=None, env_msg='{} (from {})',
|
|
falsish=FALSISH, truish=TRUISH, defaultish=DEFAULTISH,
|
|
default=False, retry=True, env_var_override=None, ofile=None, input=input, prompt=True):
|
|
"""Output <msg> (usually a question) and let user input an answer.
|
|
Qualifies the answer according to falsish, truish and defaultish as True, False or <default>.
|
|
If it didn't qualify and retry is False (no retries wanted), return the default [which
|
|
defaults to False]. If retry is True let user retry answering until answer is qualified.
|
|
|
|
If env_var_override is given and this var is present in the environment, do not ask
|
|
the user, but just use the env var contents as answer as if it was typed in.
|
|
Otherwise read input from stdin and proceed as normal.
|
|
If EOF is received instead an input or an invalid input without retry possibility,
|
|
return default.
|
|
|
|
:param msg: introducing message to output on ofile, no \n is added [None]
|
|
:param retry_msg: retry message to output on ofile, no \n is added [None]
|
|
:param false_msg: message to output before returning False [None]
|
|
:param true_msg: message to output before returning True [None]
|
|
:param default_msg: message to output before returning a <default> [None]
|
|
:param invalid_msg: message to output after a invalid answer was given [None]
|
|
:param env_msg: message to output when using input from env_var_override ['{} (from {})'],
|
|
needs to have 2 placeholders for answer and env var name
|
|
:param falsish: sequence of answers qualifying as False
|
|
:param truish: sequence of answers qualifying as True
|
|
:param defaultish: sequence of answers qualifying as <default>
|
|
:param default: default return value (defaultish answer was given or no-answer condition) [False]
|
|
:param retry: if True and input is incorrect, retry. Otherwise return default. [True]
|
|
:param env_var_override: environment variable name [None]
|
|
:param ofile: output stream [sys.stderr]
|
|
:param input: input function [input from builtins]
|
|
:return: boolean answer value, True or False
|
|
"""
|
|
# note: we do not assign sys.stderr as default above, so it is
|
|
# really evaluated NOW, not at function definition time.
|
|
if ofile is None:
|
|
ofile = sys.stderr
|
|
if default not in (True, False):
|
|
raise ValueError("invalid default value, must be True or False")
|
|
if msg:
|
|
print(msg, file=ofile, end='', flush=True)
|
|
while True:
|
|
answer = None
|
|
if env_var_override:
|
|
answer = os.environ.get(env_var_override)
|
|
if answer is not None and env_msg:
|
|
print(env_msg.format(answer, env_var_override), file=ofile)
|
|
if answer is None:
|
|
if not prompt:
|
|
return default
|
|
try:
|
|
answer = input()
|
|
except EOFError:
|
|
# avoid defaultish[0], defaultish could be empty
|
|
answer = truish[0] if default else falsish[0]
|
|
if answer in defaultish:
|
|
if default_msg:
|
|
print(default_msg, file=ofile)
|
|
return default
|
|
if answer in truish:
|
|
if true_msg:
|
|
print(true_msg, file=ofile)
|
|
return True
|
|
if answer in falsish:
|
|
if false_msg:
|
|
print(false_msg, file=ofile)
|
|
return False
|
|
# if we get here, the answer was invalid
|
|
if invalid_msg:
|
|
print(invalid_msg, file=ofile)
|
|
if not retry:
|
|
return default
|
|
if retry_msg:
|
|
print(retry_msg, file=ofile, end='', flush=True)
|
|
# in case we used an environment variable and it gave an invalid answer, do not use it again:
|
|
env_var_override = None
|
|
|
|
|
|
def ellipsis_truncate(msg, space):
|
|
"""
|
|
shorten a long string by adding ellipsis between it and return it, example:
|
|
this_is_a_very_long_string -------> this_is..._string
|
|
"""
|
|
from .platform import swidth
|
|
ellipsis_width = swidth('...')
|
|
msg_width = swidth(msg)
|
|
if space < 8:
|
|
# if there is very little space, just show ...
|
|
return '...' + ' ' * (space - ellipsis_width)
|
|
if space < ellipsis_width + msg_width:
|
|
return '%s...%s' % (swidth_slice(msg, space // 2 - ellipsis_width),
|
|
swidth_slice(msg, -space // 2))
|
|
return msg + ' ' * (space - msg_width)
|
|
|
|
|
|
class ProgressIndicatorBase:
|
|
LOGGER = 'borg.output.progress'
|
|
|
|
def __init__(self):
|
|
self.handler = None
|
|
self.logger = logging.getLogger(self.LOGGER)
|
|
|
|
# If there are no handlers, set one up explicitly because the
|
|
# terminator and propagation needs to be set. If there are,
|
|
# they must have been set up by BORG_LOGGING_CONF: skip setup.
|
|
if not self.logger.handlers:
|
|
self.handler = logging.StreamHandler(stream=sys.stderr)
|
|
self.handler.setLevel(logging.INFO)
|
|
self.handler.terminator = '\r'
|
|
|
|
self.logger.addHandler(self.handler)
|
|
if self.logger.level == logging.NOTSET:
|
|
self.logger.setLevel(logging.WARN)
|
|
self.logger.propagate = False
|
|
|
|
def __del__(self):
|
|
if self.handler is not None:
|
|
self.logger.removeHandler(self.handler)
|
|
self.handler.close()
|
|
|
|
|
|
def justify_to_terminal_size(message):
|
|
terminal_space = get_terminal_size(fallback=(-1, -1))[0]
|
|
# justify only if we are outputting to a terminal
|
|
if terminal_space != -1:
|
|
return message.ljust(terminal_space)
|
|
return message
|
|
|
|
|
|
class ProgressIndicatorMessage(ProgressIndicatorBase):
|
|
def output(self, msg):
|
|
self.logger.info(justify_to_terminal_size(msg))
|
|
|
|
def finish(self):
|
|
self.output('')
|
|
|
|
|
|
class ProgressIndicatorPercent(ProgressIndicatorBase):
|
|
def __init__(self, total=0, step=5, start=0, msg="%3.0f%%"):
|
|
"""
|
|
Percentage-based progress indicator
|
|
|
|
:param total: total amount of items
|
|
:param step: step size in percent
|
|
:param start: at which percent value to start
|
|
:param msg: output message, must contain one %f placeholder for the percentage
|
|
"""
|
|
self.counter = 0 # 0 .. (total-1)
|
|
self.total = total
|
|
self.trigger_at = start # output next percentage value when reaching (at least) this
|
|
self.step = step
|
|
self.msg = msg
|
|
|
|
super().__init__()
|
|
|
|
def progress(self, current=None, increase=1):
|
|
if current is not None:
|
|
self.counter = current
|
|
pct = self.counter * 100 / self.total
|
|
self.counter += increase
|
|
if pct >= self.trigger_at:
|
|
self.trigger_at += self.step
|
|
return pct
|
|
|
|
def show(self, current=None, increase=1, info=None):
|
|
"""
|
|
Show and output the progress message
|
|
|
|
:param current: set the current percentage [None]
|
|
:param increase: increase the current percentage [None]
|
|
:param info: array of strings to be formatted with msg [None]
|
|
"""
|
|
pct = self.progress(current, increase)
|
|
if pct is not None:
|
|
# truncate the last argument, if no space is available
|
|
if info is not None:
|
|
# no need to truncate if we're not outputing to a terminal
|
|
terminal_space = get_terminal_size(fallback=(-1, -1))[0]
|
|
if terminal_space != -1:
|
|
space = terminal_space - len(self.msg % tuple([pct] + info[:-1] + ['']))
|
|
info[-1] = ellipsis_truncate(info[-1], space)
|
|
return self.output(self.msg % tuple([pct] + info), justify=False)
|
|
|
|
return self.output(self.msg % pct)
|
|
|
|
def output(self, message, justify=True):
|
|
if justify:
|
|
message = justify_to_terminal_size(message)
|
|
self.logger.info(message)
|
|
|
|
def finish(self):
|
|
self.output('')
|
|
|
|
|
|
class ProgressIndicatorEndless:
|
|
def __init__(self, step=10, file=None):
|
|
"""
|
|
Progress indicator (long row of dots)
|
|
|
|
:param step: every Nth call, call the func
|
|
:param file: output file, default: sys.stderr
|
|
"""
|
|
self.counter = 0 # call counter
|
|
self.triggered = 0 # increases 1 per trigger event
|
|
self.step = step # trigger every <step> calls
|
|
if file is None:
|
|
file = sys.stderr
|
|
self.file = file
|
|
|
|
def progress(self):
|
|
self.counter += 1
|
|
trigger = self.counter % self.step == 0
|
|
if trigger:
|
|
self.triggered += 1
|
|
return trigger
|
|
|
|
def show(self):
|
|
trigger = self.progress()
|
|
if trigger:
|
|
return self.output(self.triggered)
|
|
|
|
def output(self, triggered):
|
|
print('.', end='', file=self.file, flush=True)
|
|
|
|
def finish(self):
|
|
print(file=self.file)
|
|
|
|
|
|
def sysinfo():
|
|
info = []
|
|
info.append('Platform: %s' % (' '.join(platform.uname()), ))
|
|
if sys.platform.startswith('linux'):
|
|
info.append('Linux: %s %s %s' % platform.linux_distribution())
|
|
info.append('Borg: %s Python: %s %s' % (borg_version, platform.python_implementation(), platform.python_version()))
|
|
info.append('PID: %d CWD: %s' % (os.getpid(), os.getcwd()))
|
|
info.append('sys.argv: %r' % sys.argv)
|
|
info.append('SSH_ORIGINAL_COMMAND: %r' % os.environ.get('SSH_ORIGINAL_COMMAND'))
|
|
info.append('')
|
|
return '\n'.join(info)
|
|
|
|
|
|
def log_multi(*msgs, level=logging.INFO, logger=logger):
|
|
"""
|
|
log multiple lines of text, each line by a separate logging call for cosmetic reasons
|
|
|
|
each positional argument may be a single or multiple lines (separated by newlines) of text.
|
|
"""
|
|
lines = []
|
|
for msg in msgs:
|
|
lines.extend(msg.splitlines())
|
|
for line in lines:
|
|
logger.log(level, line)
|
|
|
|
|
|
class BaseFormatter:
|
|
FIXED_KEYS = {
|
|
# Formatting aids
|
|
'LF': '\n',
|
|
'SPACE': ' ',
|
|
'TAB': '\t',
|
|
'CR': '\r',
|
|
'NUL': '\0',
|
|
'NEWLINE': os.linesep,
|
|
'NL': os.linesep,
|
|
}
|
|
|
|
def get_item_data(self, item):
|
|
raise NotImplementedError
|
|
|
|
def format_item(self, item):
|
|
return self.format.format_map(self.get_item_data(item))
|
|
|
|
@staticmethod
|
|
def keys_help():
|
|
return " - NEWLINE: OS dependent line separator\n" \
|
|
" - NL: alias of NEWLINE\n" \
|
|
" - NUL: NUL character for creating print0 / xargs -0 like output, see barchive/bpath\n" \
|
|
" - SPACE\n" \
|
|
" - TAB\n" \
|
|
" - CR\n" \
|
|
" - LF"
|
|
|
|
|
|
class ArchiveFormatter(BaseFormatter):
|
|
|
|
def __init__(self, format):
|
|
self.format = partial_format(format, self.FIXED_KEYS)
|
|
|
|
def get_item_data(self, archive):
|
|
return {
|
|
'barchive': archive.name,
|
|
'archive': remove_surrogates(archive.name),
|
|
'id': bin_to_hex(archive.id),
|
|
'time': format_time(to_localtime(archive.ts)),
|
|
}
|
|
|
|
@staticmethod
|
|
def keys_help():
|
|
return " - archive: archive name interpreted as text (might be missing non-text characters, see barchive)\n" \
|
|
" - barchive: verbatim archive name, can contain any character except NUL\n" \
|
|
" - time: time of creation of the archive\n" \
|
|
" - id: internal ID of the archive"
|
|
|
|
|
|
class ItemFormatter(BaseFormatter):
|
|
KEY_DESCRIPTIONS = {
|
|
'bpath': 'verbatim POSIX path, can contain any character except NUL',
|
|
'path': 'path interpreted as text (might be missing non-text characters, see bpath)',
|
|
'source': 'link target for links (identical to linktarget)',
|
|
'extra': 'prepends {source} with " -> " for soft links and " link to " for hard links',
|
|
'csize': 'compressed size',
|
|
'num_chunks': 'number of chunks in this file',
|
|
'unique_chunks': 'number of unique chunks in this file',
|
|
'health': 'either "healthy" (file ok) or "broken" (if file has all-zero replacement chunks)',
|
|
}
|
|
KEY_GROUPS = (
|
|
('type', 'mode', 'uid', 'gid', 'user', 'group', 'path', 'bpath', 'source', 'linktarget', 'flags'),
|
|
('size', 'csize', 'num_chunks', 'unique_chunks'),
|
|
('mtime', 'ctime', 'atime', 'isomtime', 'isoctime', 'isoatime'),
|
|
tuple(sorted(hashlib.algorithms_guaranteed)),
|
|
('archiveid', 'archivename', 'extra'),
|
|
('health', )
|
|
)
|
|
|
|
@classmethod
|
|
def available_keys(cls):
|
|
class FakeArchive:
|
|
fpr = name = ""
|
|
|
|
from .item import Item
|
|
fake_item = Item(mode=0, path='', user='', group='', mtime=0, uid=0, gid=0)
|
|
formatter = cls(FakeArchive, "")
|
|
keys = []
|
|
keys.extend(formatter.call_keys.keys())
|
|
keys.extend(formatter.get_item_data(fake_item).keys())
|
|
return keys
|
|
|
|
@classmethod
|
|
def keys_help(cls):
|
|
help = []
|
|
keys = cls.available_keys()
|
|
for key in cls.FIXED_KEYS:
|
|
keys.remove(key)
|
|
|
|
for group in cls.KEY_GROUPS:
|
|
for key in group:
|
|
keys.remove(key)
|
|
text = " - " + key
|
|
if key in cls.KEY_DESCRIPTIONS:
|
|
text += ": " + cls.KEY_DESCRIPTIONS[key]
|
|
help.append(text)
|
|
help.append("")
|
|
assert not keys, str(keys)
|
|
return "\n".join(help)
|
|
|
|
def __init__(self, archive, format):
|
|
self.archive = archive
|
|
static_keys = {
|
|
'archivename': archive.name,
|
|
'archiveid': archive.fpr,
|
|
}
|
|
static_keys.update(self.FIXED_KEYS)
|
|
self.format = partial_format(format, static_keys)
|
|
self.format_keys = {f[1] for f in Formatter().parse(format)}
|
|
self.call_keys = {
|
|
'size': self.calculate_size,
|
|
'csize': self.calculate_csize,
|
|
'num_chunks': self.calculate_num_chunks,
|
|
'unique_chunks': self.calculate_unique_chunks,
|
|
'isomtime': partial(self.format_time, 'mtime'),
|
|
'isoctime': partial(self.format_time, 'ctime'),
|
|
'isoatime': partial(self.format_time, 'atime'),
|
|
'mtime': partial(self.time, 'mtime'),
|
|
'ctime': partial(self.time, 'ctime'),
|
|
'atime': partial(self.time, 'atime'),
|
|
}
|
|
for hash_function in hashlib.algorithms_guaranteed:
|
|
self.add_key(hash_function, partial(self.hash_item, hash_function))
|
|
self.used_call_keys = set(self.call_keys) & self.format_keys
|
|
self.item_data = static_keys
|
|
|
|
def add_key(self, key, callable_with_item):
|
|
self.call_keys[key] = callable_with_item
|
|
self.used_call_keys = set(self.call_keys) & self.format_keys
|
|
|
|
def get_item_data(self, item):
|
|
mode = stat.filemode(item.mode)
|
|
item_type = mode[0]
|
|
item_data = self.item_data
|
|
|
|
source = item.get('source', '')
|
|
extra = ''
|
|
if source:
|
|
source = remove_surrogates(source)
|
|
if item_type == 'l':
|
|
extra = ' -> %s' % source
|
|
else:
|
|
mode = 'h' + mode[1:]
|
|
extra = ' link to %s' % source
|
|
item_data['type'] = item_type
|
|
item_data['mode'] = mode
|
|
item_data['user'] = item.user or item.uid
|
|
item_data['group'] = item.group or item.gid
|
|
item_data['uid'] = item.uid
|
|
item_data['gid'] = item.gid
|
|
item_data['path'] = remove_surrogates(item.path)
|
|
item_data['bpath'] = item.path
|
|
item_data['source'] = source
|
|
item_data['linktarget'] = source
|
|
item_data['extra'] = extra
|
|
item_data['flags'] = item.get('bsdflags')
|
|
item_data['health'] = 'broken' if 'chunks_healthy' in item else 'healthy'
|
|
for key in self.used_call_keys:
|
|
item_data[key] = self.call_keys[key](item)
|
|
return item_data
|
|
|
|
def calculate_num_chunks(self, item):
|
|
return len(item.get('chunks', []))
|
|
|
|
def calculate_unique_chunks(self, item):
|
|
chunk_index = self.archive.cache.chunks
|
|
return sum(1 for c in item.get('chunks', []) if chunk_index[c.id].refcount == 1)
|
|
|
|
def calculate_size(self, item):
|
|
return sum(c.size for c in item.get('chunks', []))
|
|
|
|
def calculate_csize(self, item):
|
|
return sum(c.csize for c in item.get('chunks', []))
|
|
|
|
def hash_item(self, hash_function, item):
|
|
if 'chunks' not in item:
|
|
return ""
|
|
hash = hashlib.new(hash_function)
|
|
for _, data in self.archive.pipeline.fetch_many([c.id for c in item.chunks]):
|
|
hash.update(data)
|
|
return hash.hexdigest()
|
|
|
|
def format_time(self, key, item):
|
|
return format_time(safe_timestamp(item.get(key) or item.mtime))
|
|
|
|
def time(self, key, item):
|
|
return safe_timestamp(item.get(key) or item.mtime)
|
|
|
|
|
|
class ChunkIteratorFileWrapper:
|
|
"""File-like wrapper for chunk iterators"""
|
|
|
|
def __init__(self, chunk_iterator):
|
|
self.chunk_iterator = chunk_iterator
|
|
self.chunk_offset = 0
|
|
self.chunk = b''
|
|
self.exhausted = False
|
|
|
|
def _refill(self):
|
|
remaining = len(self.chunk) - self.chunk_offset
|
|
if not remaining:
|
|
try:
|
|
chunk = next(self.chunk_iterator)
|
|
self.chunk = memoryview(chunk.data)
|
|
except StopIteration:
|
|
self.exhausted = True
|
|
return 0 # EOF
|
|
self.chunk_offset = 0
|
|
remaining = len(self.chunk)
|
|
return remaining
|
|
|
|
def _read(self, nbytes):
|
|
if not nbytes:
|
|
return b''
|
|
remaining = self._refill()
|
|
will_read = min(remaining, nbytes)
|
|
self.chunk_offset += will_read
|
|
return self.chunk[self.chunk_offset - will_read:self.chunk_offset]
|
|
|
|
def read(self, nbytes):
|
|
parts = []
|
|
while nbytes and not self.exhausted:
|
|
read_data = self._read(nbytes)
|
|
nbytes -= len(read_data)
|
|
parts.append(read_data)
|
|
return b''.join(parts)
|
|
|
|
|
|
def open_item(archive, item):
|
|
"""Return file-like object for archived item (with chunks)."""
|
|
chunk_iterator = archive.pipeline.fetch_many([c.id for c in item.chunks])
|
|
return ChunkIteratorFileWrapper(chunk_iterator)
|
|
|
|
|
|
def file_status(mode):
|
|
if stat.S_ISREG(mode):
|
|
return 'A'
|
|
elif stat.S_ISDIR(mode):
|
|
return 'd'
|
|
elif stat.S_ISBLK(mode):
|
|
return 'b'
|
|
elif stat.S_ISCHR(mode):
|
|
return 'c'
|
|
elif stat.S_ISLNK(mode):
|
|
return 's'
|
|
elif stat.S_ISFIFO(mode):
|
|
return 'f'
|
|
return '?'
|
|
|
|
|
|
def chunkit(it, size):
|
|
"""
|
|
Chunk an iterator <it> into pieces of <size>.
|
|
|
|
>>> list(chunker('ABCDEFG', 3))
|
|
[['A', 'B', 'C'], ['D', 'E', 'F'], ['G']]
|
|
"""
|
|
iterable = iter(it)
|
|
return iter(lambda: list(islice(iterable, size)), [])
|
|
|
|
|
|
def consume(iterator, n=None):
|
|
"""Advance the iterator n-steps ahead. If n is none, consume entirely."""
|
|
# Use functions that consume iterators at C speed.
|
|
if n is None:
|
|
# feed the entire iterator into a zero-length deque
|
|
deque(iterator, maxlen=0)
|
|
else:
|
|
# advance to the empty slice starting at position n
|
|
next(islice(iterator, n, n), None)
|
|
|
|
# GenericDirEntry, scandir_generic (c) 2012 Ben Hoyt
|
|
# from the python-scandir package (3-clause BSD license, just like us, so no troubles here)
|
|
# note: simplified version
|
|
|
|
|
|
class GenericDirEntry:
|
|
__slots__ = ('name', '_scandir_path', '_path')
|
|
|
|
def __init__(self, scandir_path, name):
|
|
self._scandir_path = scandir_path
|
|
self.name = name
|
|
self._path = None
|
|
|
|
@property
|
|
def path(self):
|
|
if self._path is None:
|
|
self._path = os.path.join(self._scandir_path, self.name)
|
|
return self._path
|
|
|
|
def stat(self, follow_symlinks=True):
|
|
assert not follow_symlinks
|
|
return os.lstat(self.path)
|
|
|
|
def _check_type(self, type):
|
|
st = self.stat(False)
|
|
return stat.S_IFMT(st.st_mode) == type
|
|
|
|
def is_dir(self, follow_symlinks=True):
|
|
assert not follow_symlinks
|
|
return self._check_type(stat.S_IFDIR)
|
|
|
|
def is_file(self, follow_symlinks=True):
|
|
assert not follow_symlinks
|
|
return self._check_type(stat.S_IFREG)
|
|
|
|
def is_symlink(self):
|
|
return self._check_type(stat.S_IFLNK)
|
|
|
|
def inode(self):
|
|
st = self.stat(False)
|
|
return st.st_ino
|
|
|
|
def __repr__(self):
|
|
return '<{0}: {1!r}>'.format(self.__class__.__name__, self.path)
|
|
|
|
|
|
def scandir_generic(path='.'):
|
|
"""Like os.listdir(), but yield DirEntry objects instead of returning a list of names."""
|
|
for name in sorted(os.listdir(path)):
|
|
yield GenericDirEntry(path, name)
|
|
|
|
|
|
try:
|
|
from os import scandir
|
|
except ImportError:
|
|
try:
|
|
# Try python-scandir on Python 3.4
|
|
from scandir import scandir
|
|
except ImportError:
|
|
# If python-scandir is not installed, then use a version that is just as slow as listdir.
|
|
scandir = scandir_generic
|
|
|
|
|
|
def scandir_inorder(path='.'):
|
|
return sorted(scandir(path), key=lambda dirent: dirent.inode())
|
|
|
|
|
|
def clean_lines(lines, lstrip=None, rstrip=None, remove_empty=True, remove_comments=True):
|
|
"""
|
|
clean lines (usually read from a config file):
|
|
|
|
1. strip whitespace (left and right), 2. remove empty lines, 3. remove comments.
|
|
|
|
note: only "pure comment lines" are supported, no support for "trailing comments".
|
|
|
|
:param lines: input line iterator (e.g. list or open text file) that gives unclean input lines
|
|
:param lstrip: lstrip call arguments or False, if lstripping is not desired
|
|
:param rstrip: rstrip call arguments or False, if rstripping is not desired
|
|
:param remove_comments: remove comment lines (lines starting with "#")
|
|
:param remove_empty: remove empty lines
|
|
:return: yields processed lines
|
|
"""
|
|
for line in lines:
|
|
if lstrip is not False:
|
|
line = line.lstrip(lstrip)
|
|
if rstrip is not False:
|
|
line = line.rstrip(rstrip)
|
|
if remove_empty and not line:
|
|
continue
|
|
if remove_comments and line.startswith('#'):
|
|
continue
|
|
yield line
|
|
|
|
|
|
class CompressionDecider1:
|
|
def __init__(self, compression, compression_files):
|
|
"""
|
|
Initialize a CompressionDecider instance (and read config files, if needed).
|
|
|
|
:param compression: default CompressionSpec (e.g. from --compression option)
|
|
:param compression_files: list of compression config files (e.g. from --compression-from) or
|
|
a list of other line iterators
|
|
"""
|
|
self.compression = compression
|
|
if not compression_files:
|
|
self.matcher = None
|
|
else:
|
|
self.matcher = PatternMatcher(fallback=compression)
|
|
for file in compression_files:
|
|
try:
|
|
for line in clean_lines(file):
|
|
try:
|
|
compr_spec, fn_pattern = line.split(':', 1)
|
|
except:
|
|
continue
|
|
self.matcher.add([parse_pattern(fn_pattern)], CompressionSpec(compr_spec))
|
|
finally:
|
|
if hasattr(file, 'close'):
|
|
file.close()
|
|
|
|
def decide(self, path):
|
|
if self.matcher is not None:
|
|
return self.matcher.match(path)
|
|
return self.compression
|
|
|
|
|
|
class CompressionDecider2:
|
|
logger = create_logger('borg.debug.file-compression')
|
|
|
|
def __init__(self, compression):
|
|
self.compression = compression
|
|
|
|
def decide(self, chunk):
|
|
# nothing fancy here yet: we either use what the metadata says or the default
|
|
# later, we can decide based on the chunk data also.
|
|
# if we compress the data here to decide, we can even update the chunk data
|
|
# and modify the metadata as desired.
|
|
compr_spec = chunk.meta.get('compress', self.compression)
|
|
if compr_spec['name'] == 'auto':
|
|
# we did not decide yet, use heuristic:
|
|
compr_spec, chunk = self.heuristic_lz4(compr_spec, chunk)
|
|
return compr_spec, chunk
|
|
|
|
def heuristic_lz4(self, compr_args, chunk):
|
|
from .compress import get_compressor
|
|
meta, data = chunk
|
|
lz4 = get_compressor('lz4')
|
|
cdata = lz4.compress(data)
|
|
data_len = len(data)
|
|
cdata_len = len(cdata)
|
|
if cdata_len < data_len:
|
|
compr_spec = compr_args['spec']
|
|
else:
|
|
# uncompressible - we could have a special "uncompressible compressor"
|
|
# that marks such data as uncompressible via compression-type metadata.
|
|
compr_spec = CompressionSpec('none')
|
|
compr_args.update(compr_spec)
|
|
self.logger.debug("len(data) == %d, len(lz4(data)) == %d, choosing %s", data_len, cdata_len, compr_spec)
|
|
return compr_args, Chunk(data, **meta)
|
|
|
|
|
|
class ErrorIgnoringTextIOWrapper(io.TextIOWrapper):
|
|
def read(self, n):
|
|
if not self.closed:
|
|
try:
|
|
return super().read(n)
|
|
except BrokenPipeError:
|
|
try:
|
|
super().close()
|
|
except OSError:
|
|
pass
|
|
return ''
|
|
|
|
def write(self, s):
|
|
if not self.closed:
|
|
try:
|
|
return super().write(s)
|
|
except BrokenPipeError:
|
|
try:
|
|
super().close()
|
|
except OSError:
|
|
pass
|
|
return len(s)
|
|
|
|
|
|
class SignalException(BaseException):
|
|
"""base class for all signal-based exceptions"""
|
|
|
|
|
|
class SigHup(SignalException):
|
|
"""raised on SIGHUP signal"""
|
|
|
|
|
|
class SigTerm(SignalException):
|
|
"""raised on SIGTERM signal"""
|
|
|
|
|
|
@contextlib.contextmanager
|
|
def signal_handler(sig, handler):
|
|
"""
|
|
when entering context, set up signal handler <handler> for signal <sig>.
|
|
when leaving context, restore original signal handler.
|
|
|
|
<sig> can bei either a str when giving a signal.SIGXXX attribute name (it
|
|
won't crash if the attribute name does not exist as some names are platform
|
|
specific) or a int, when giving a signal number.
|
|
|
|
<handler> is any handler value as accepted by the signal.signal(sig, handler).
|
|
"""
|
|
if isinstance(sig, str):
|
|
sig = getattr(signal, sig, None)
|
|
if sig is not None:
|
|
orig_handler = signal.signal(sig, handler)
|
|
try:
|
|
yield
|
|
finally:
|
|
if sig is not None:
|
|
signal.signal(sig, orig_handler)
|
|
|
|
|
|
def raising_signal_handler(exc_cls):
|
|
def handler(sig_no, frame):
|
|
# setting SIG_IGN avoids that an incoming second signal of this
|
|
# kind would raise a 2nd exception while we still process the
|
|
# exception handler for exc_cls for the 1st signal.
|
|
signal.signal(sig_no, signal.SIG_IGN)
|
|
raise exc_cls
|
|
|
|
return handler
|
|
|
|
|
|
def swidth_slice(string, max_width):
|
|
"""
|
|
Return a slice of *max_width* cells from *string*.
|
|
|
|
Negative *max_width* means from the end of string.
|
|
|
|
*max_width* is in units of character cells (or "columns").
|
|
Latin characters are usually one cell wide, many CJK characters are two cells wide.
|
|
"""
|
|
from .platform import swidth
|
|
reverse = max_width < 0
|
|
max_width = abs(max_width)
|
|
if reverse:
|
|
string = reversed(string)
|
|
current_swidth = 0
|
|
result = []
|
|
for character in string:
|
|
current_swidth += swidth(character)
|
|
if current_swidth > max_width:
|
|
break
|
|
result.append(character)
|
|
if reverse:
|
|
result.reverse()
|
|
return ''.join(result)
|