91b7bb133c
* Add an explicit one-filesystem policy to backups scantree() gains an opt-in one_filesystem flag: when a subdirectory's device differs from the walk root's (a mount point), its contents are excluded from the walk. The mount-point directory itself is still yielded, so it appears as an empty directory in the backup rather than vanishing silently - matching rsync's --one-file-system behavior. Wired into rsync()'s two source-tree walks so backups never silently pull in content from a bind mount or other filesystem mounted under the source tree. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> * Fix one-filesystem policy: symlinked root and external rsync parity - scantree() computed the walk root's device with os.lstat(), but scandir() follows the root path if it's a symlink. A symlinked root would compute the symlink's own device instead of the target directory's, making every real subdirectory look cross-device and get its contents wrongly excluded. Use os.stat() for the root only. - rsync_ext() (the external-rsync backend) didn't pass --one-file-system, so backups using external_rsync=True still crossed mount points despite the pure-Python path now refusing to. Addresses GitHub Copilot review feedback on PR #18. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> --------- Co-authored-by: Maxim Shulga <maxim.shulga@alludo.com> Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
797 lines
30 KiB
Python
797 lines
30 KiB
Python
"""
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Module with filesystem-related functions.
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"""
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import enum
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import glob
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import hashlib
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import logging
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import os
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import stat
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import subprocess
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import sys
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import uuid
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from typing import Iterable, Optional, Tuple, Union
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_lg = logging.getLogger(__name__)
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class BackupCreationError(Exception):
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pass
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class Actions(enum.Enum):
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NOTHING = enum.auto()
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DELETE = enum.auto()
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REWRITE = enum.auto()
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UPDATE_TIME = enum.auto()
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UPDATE_PERM = enum.auto()
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UPDATE_OWNER = enum.auto()
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CREATE = enum.auto()
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ERROR = enum.auto()
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EXCLUDE = enum.auto()
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# Entry kinds copy_direntry() knows how to back up. Everything else
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# (FIFOs, sockets, block/char devices, and anything lstat() doesn't
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# recognize) is classified and excluded without ever being opened - a
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# FIFO with no writer would otherwise block open() for read forever, and
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# reading a device node can return unbounded or meaningless data.
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_SUPPORTED_KINDS = frozenset({"file", "dir", "symlink"})
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def entry_kind(entry: Union[os.DirEntry, "PseudoDirEntry"]) -> str:
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"""
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Classify a filesystem entry via lstat() mode bits alone - never
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opens it, so classifying a FIFO can't block even without a writer.
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:return: one of "file", "dir", "symlink", "fifo", "socket",
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"block_device", "char_device", "unknown".
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"""
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mode = entry.stat(follow_symlinks=False).st_mode
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if stat.S_ISLNK(mode):
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return "symlink"
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if stat.S_ISDIR(mode):
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return "dir"
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if stat.S_ISREG(mode):
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return "file"
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if stat.S_ISFIFO(mode):
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return "fifo"
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if stat.S_ISSOCK(mode):
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return "socket"
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if stat.S_ISBLK(mode):
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return "block_device"
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if stat.S_ISCHR(mode):
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return "char_device"
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return "unknown"
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class PseudoDirEntry:
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"""
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Duck-typed os.DirEntry for paths that don't exist yet or when you need
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DirEntry-like interface for arbitrary paths.
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Problem: os.DirEntry is created by os.scandir() and cannot be manually
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constructed. But we need DirEntry-compatible objects for:
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- Paths that will exist soon (new backup directories)
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- Constructed paths (marker files)
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- Uniform interface in functions accepting both real and future entries
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Why not just use strings? Functions like rm_direntry(), copy_direntry()
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accept Union[os.DirEntry, PseudoDirEntry] and call .is_dir(), .stat()
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methods. Using this class avoids branching on type throughout the codebase.
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Why not pathlib.Path? We heavily use os.scandir() which returns DirEntry
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objects with cached stat info. PseudoDirEntry maintains API consistency
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with minimal overhead.
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Example usage:
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# Create entry for future backup directory
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cur_backup = PseudoDirEntry("/backups/20260204_120000")
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os.mkdir(cur_backup.path)
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set_backup_marker(cur_backup) # accepts DirEntry-like object
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Caches stat results like real DirEntry to avoid repeated syscalls.
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"""
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def __init__(self, path):
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# Use abspath, not realpath - realpath resolves symlinks
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self.path = os.path.abspath(path)
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self.name = os.path.basename(self.path)
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self._is_dir = None
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self._is_file = None
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self._is_symlink = None
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# Cache both stat and lstat separately
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self._stat_follow = None
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self._stat_nofollow = None
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def __str__(self):
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return self.name
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def is_dir(self, follow_symlinks: bool = True) -> bool:
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if follow_symlinks:
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if self._is_dir is None:
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self._is_dir = os.path.isdir(self.path)
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return self._is_dir
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else:
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# When not following symlinks, must return False if path is symlink
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return os.path.isdir(self.path) and not os.path.islink(self.path)
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def is_file(self, follow_symlinks: bool = True) -> bool:
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if follow_symlinks:
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if self._is_file is None:
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self._is_file = os.path.isfile(self.path)
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return self._is_file
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else:
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# When not following symlinks, must return False if path is symlink
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return os.path.isfile(self.path) and not os.path.islink(self.path)
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def is_symlink(self) -> bool:
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if self._is_symlink is None:
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self._is_symlink = os.path.islink(self.path)
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return self._is_symlink
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def stat(self, follow_symlinks: bool = True):
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if follow_symlinks:
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if self._stat_follow is None:
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self._stat_follow = os.stat(self.path)
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return self._stat_follow
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else:
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if self._stat_nofollow is None:
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self._stat_nofollow = os.lstat(self.path)
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return self._stat_nofollow
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def _parse_rsync_output(line: str) -> Tuple[str, Actions, str]:
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action = None
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change_string, relpath = line.split(' ', maxsplit=1)
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if change_string == "*deleting":
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return relpath, Actions.DELETE, ""
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update_type = change_string[0]
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entity_type = change_string[1]
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change_type = change_string[2:]
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if update_type == "c" and entity_type in {"d", "L"} and "+" in change_type:
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action = Actions.CREATE
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elif update_type == ">" and entity_type == "f" and "+" in change_type:
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action = Actions.CREATE
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elif entity_type == "f" and ("s" in change_type or "t" in change_type):
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action = Actions.REWRITE
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elif entity_type == "d" and "t" in change_type:
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action = Actions.UPDATE_TIME
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elif "p" in change_type:
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action = Actions.UPDATE_PERM
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elif "o" in change_type or "g" in change_type:
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action = Actions.UPDATE_OWNER
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if action is None:
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raise RuntimeError("Not parsed string: %s" % line)
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return relpath, action, ""
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def rsync_ext(src, dst, dry_run=False) -> Iterable[Tuple[str, Actions, str]]:
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"""
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Call external rsync command for syncing files from src to dst.
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Yield (path, action, error message) tuples.
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"""
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rsync_args = ["rsync"]
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if dry_run:
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rsync_args.append("--dry-run")
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rsync_args.append("--archive")
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# rsync_args.append("--compress")
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# rsync_args.append("--inplace")
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rsync_args.append("--whole-file")
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rsync_args.append("--human-readable")
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rsync_args.append("--one-file-system")
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rsync_args.append("--delete-during")
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rsync_args.append("--itemize-changes")
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rsync_args.append(f"{src}/")
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rsync_args.append(str(dst))
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_lg.info("Executing external command: %s", " ".join(rsync_args))
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process = subprocess.Popen(rsync_args,
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stdout=subprocess.PIPE,
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stderr=subprocess.STDOUT)
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with process.stdout:
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prev_line = None
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for line in iter(process.stdout.readline, b""):
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_lg.debug("Rsync current line: %s", line)
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if prev_line is None:
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prev_line = line
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continue
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try:
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prev_line = prev_line.decode("utf-8").strip()
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# some issues with cyrillic in filenames
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except UnicodeDecodeError:
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_lg.error("Can't process rsync line: %s", prev_line)
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continue
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_lg.debug("Rsync itemize line: %s", prev_line)
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yield _parse_rsync_output(prev_line)
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prev_line = line
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try:
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prev_line = prev_line.decode("utf-8").strip()
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_lg.debug("Rsync itemize line: %s", prev_line)
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yield _parse_rsync_output(prev_line)
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# some issues with cyrillic in filenames
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except UnicodeDecodeError:
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_lg.error("Can't process rsync line: %s", prev_line)
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process.wait()
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def scantree(path, dir_first=True,
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one_filesystem=False, _root_dev=None) -> Iterable[os.DirEntry]:
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"""
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Recursively yield DirEntry objects (dir/file/symlink) for given directory.
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:param one_filesystem: if True, don't descend into a subdirectory that
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lives on a different device than `path` (a mount point). The
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directory itself is still yielded, so it appears as an empty
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directory in the walk - only its contents are excluded. Matches
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rsync's --one-file-system behavior.
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"""
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if one_filesystem and _root_dev is None:
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# os.stat(), not os.lstat(): scandir() follows `path` if it's a
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# symlink, so the root device must be the resolved directory's,
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# not the symlink's own.
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_root_dev = os.stat(path).st_dev
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entry: os.DirEntry
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with os.scandir(path) as scan_it:
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for entry in scan_it:
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if entry.is_dir(follow_symlinks=False):
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if (one_filesystem
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and os.lstat(entry.path).st_dev != _root_dev):
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_lg.warning(
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"Scantree, excluding mount point contents: %s",
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entry.path)
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yield entry
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continue
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if dir_first:
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yield entry
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yield from scantree(entry.path, dir_first,
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one_filesystem, _root_dev)
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if not dir_first:
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yield entry
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else:
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yield entry
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def rm_direntry(entry: Union[os.DirEntry, PseudoDirEntry]):
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"""
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Recursively delete DirEntry. Directories are removed recursively;
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anything else (file, symlink, or a special entry like a FIFO,
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socket, or device node) is unlinked directly.
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"""
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if entry.is_dir(follow_symlinks=False):
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with os.scandir(entry.path) as it:
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child_entry: os.DirEntry
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for child_entry in it:
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rm_direntry(child_entry)
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os.rmdir(entry.path)
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else:
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os.unlink(entry.path)
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try:
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O_BINARY = os.O_BINARY # Windows only
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except AttributeError:
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O_BINARY = 0
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READ_FLAGS = os.O_RDONLY | O_BINARY
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WRITE_FLAGS = os.O_WRONLY | os.O_CREAT | os.O_TRUNC | O_BINARY
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BUFFER_SIZE = 128 * 1024
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def _write_all(fd: int, data: bytes):
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"""os.write() may write fewer bytes than given; loop until it's all out."""
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view = memoryview(data)
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while view:
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written = os.write(fd, view)
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view = view[written:]
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def copy_file(src, dst) -> str:
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"""
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Copy file from src to dst. Faster than shutil.copy.
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Compares fstat() on the source's own open file descriptor before and
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after the read loop - this reflects the underlying inode directly, so
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it catches the source being truncated, grown, or overwritten in place
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while being read (and isn't fooled by the source path being renamed
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or unlinked mid-copy, since the descriptor keeps referring to the
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same inode regardless). Nanosecond mtime is used so a same-second
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modification can't slip past undetected.
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:return: sha256 hex digest of the bytes actually copied.
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:raises BackupCreationError: if the source changed while being read.
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"""
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fin = None
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fout = None
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try:
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fin = os.open(src, READ_FLAGS)
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stat_before = os.fstat(fin)
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fout = os.open(dst, WRITE_FLAGS, stat_before.st_mode)
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digest = hashlib.sha256()
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for chunk in iter(lambda: os.read(fin, BUFFER_SIZE), b""):
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_write_all(fout, chunk)
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digest.update(chunk)
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stat_after = os.fstat(fin)
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if (stat_after.st_size != stat_before.st_size
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or stat_after.st_mtime_ns != stat_before.st_mtime_ns):
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raise BackupCreationError(
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"Source file changed while being copied: %s" % src
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)
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return digest.hexdigest()
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finally:
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if fout is not None:
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try:
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os.close(fout)
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except OSError:
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pass
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if fin is not None:
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try:
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os.close(fin)
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except OSError:
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pass
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def _break_shared_hardlink(path: str):
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"""
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Give `path` a private inode if it currently shares one with another
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file (nlink > 1), so a subsequent in-place metadata change (chmod,
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chown, utime, flags) can never mutate that other file. Files copied
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into a staging directory via hardlink_dir() start out hardlinked to
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the previous snapshot; this is the copy-on-write step that keeps
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that previous, completed snapshot immutable.
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The break itself must be metadata-neutral: copy_file() only carries
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over the mode at file-creation time, not ownership or timestamps, so
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the new private copy is explicitly restored to the original's full
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stat before it replaces `path` - otherwise a caller that only meant
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to update permissions would silently also reset ownership/mtime as a
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side effect of this implementation detail.
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"""
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st = os.lstat(path)
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if st.st_nlink <= 1:
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return
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tmp_path = "%s.cow-%d-%s" % (path, os.getpid(), uuid.uuid4().hex[:8])
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try:
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copy_file(path, tmp_path)
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try:
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os.chown(tmp_path, st.st_uid, st.st_gid)
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except PermissionError:
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_lg.debug("Cannot preserve ownership while breaking hardlink "
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"(not root): %s", path)
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os.chmod(tmp_path, st.st_mode)
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os.utime(tmp_path, ns=(st.st_atime_ns, st.st_mtime_ns))
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os.replace(tmp_path, path)
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except (OSError, BackupCreationError):
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try:
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os.unlink(tmp_path)
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except OSError:
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pass
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raise
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def copy_direntry(entry: Union[os.DirEntry, PseudoDirEntry],
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dst_path) -> Optional[str]:
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"""
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Non-recursive DirEntry (file/dir/symlink) copy.
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:return: sha256 hex digest of the copied content for a regular file,
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None for a directory or symlink (nothing to hash).
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"""
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src_stat = entry.stat(follow_symlinks=False)
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digest = None
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# Classify with lstat semantics and check symlink-ness first: is_dir()
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# (and is_file()) default to follow_symlinks=True, so a symlink
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# pointing at a directory would otherwise be misclassified as a
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# directory here and get an empty directory created in its place,
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# silently losing the symlink and its target.
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if entry.is_symlink():
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link_target = os.readlink(entry.path)
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os.symlink(link_target, dst_path)
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elif entry.is_dir(follow_symlinks=False):
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os.mkdir(dst_path)
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else:
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digest = copy_file(entry.path, dst_path)
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# Nanosecond timestamps: st_mtime (float seconds) loses sub-second
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# precision, which could make a real content change on a fast-moving
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# file look identical to an unrelated file with the same whole-second
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# mtime once rounded.
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if entry.is_symlink():
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# change symlink attributes only if supported by OS
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if os.chown in os.supports_follow_symlinks:
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try:
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os.chown(dst_path, src_stat.st_uid, src_stat.st_gid,
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follow_symlinks=False)
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except PermissionError:
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_lg.debug("Cannot change ownership (not root): %s", dst_path)
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if os.chmod in os.supports_follow_symlinks:
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os.chmod(dst_path, src_stat.st_mode, follow_symlinks=False)
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if os.utime in os.supports_follow_symlinks:
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os.utime(dst_path,
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ns=(src_stat.st_atime_ns, src_stat.st_mtime_ns),
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follow_symlinks=False)
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else:
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try:
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os.chown(dst_path, src_stat.st_uid, src_stat.st_gid)
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except PermissionError:
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_lg.debug("Cannot change ownership (not root): %s", dst_path)
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os.chmod(dst_path, src_stat.st_mode)
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os.utime(dst_path, ns=(src_stat.st_atime_ns, src_stat.st_mtime_ns))
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return digest
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def update_direntry(src_entry: os.DirEntry,
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dst_entry: os.DirEntry) -> Optional[str]:
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"""
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Make dst DirEntry (file/dir/symlink) same as src.
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If dst is directory, its content will be removed.
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Src dir content will not be copied into dst dir.
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:return: see copy_direntry().
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"""
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rm_direntry(dst_entry)
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return copy_direntry(src_entry, dst_entry.path)
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|
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def rsync(src_dir,
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dst_dir,
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dry_run=False) -> Iterable[Tuple[str, Actions, str]]:
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"""
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Sync files/dirs/symlinks from src_dir to dst_dir.
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Yield (path, action, error message) tuples.
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Entries in dst_dir will be removed if not present in src_dir.
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Analog of 'rsync --delete -irltpog'.
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"""
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_lg.debug("Rsync: %s -> %s", src_dir, dst_dir)
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src_root_abs = os.path.abspath(src_dir)
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dst_root_abs = os.path.abspath(dst_dir)
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if not os.path.isdir(src_root_abs):
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raise BackupCreationError(
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"Error during reading source directory: %s" % src_root_abs
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)
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if os.path.exists(dst_root_abs):
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if not os.path.isdir(dst_root_abs):
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raise BackupCreationError(
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|
"Destination path is not a directory: %s" % dst_root_abs
|
|
)
|
|
else:
|
|
os.mkdir(dst_root_abs)
|
|
|
|
# Create source map {rel_path: dir_entry}
|
|
src_files_map = {
|
|
ent.path[len(src_root_abs) + 1:]: ent
|
|
for ent in scantree(src_root_abs, one_filesystem=True)
|
|
}
|
|
|
|
# process dst tree
|
|
for dst_entry in scantree(dst_root_abs, dir_first=False):
|
|
rel_path = dst_entry.path[len(dst_root_abs) + 1:]
|
|
|
|
src_entry = src_files_map.get(rel_path)
|
|
|
|
# remove dst entries not existing in source
|
|
if src_entry is None:
|
|
_lg.debug("Rsync, deleting: %s", rel_path)
|
|
try:
|
|
rm_direntry(dst_entry)
|
|
yield rel_path, Actions.DELETE, ""
|
|
continue
|
|
except OSError as exc:
|
|
raise BackupCreationError(exc) from exc
|
|
|
|
# mark src entry as taken for processing
|
|
del src_files_map[rel_path]
|
|
|
|
src_entry: os.DirEntry
|
|
src_kind = entry_kind(src_entry)
|
|
if src_kind not in _SUPPORTED_KINDS:
|
|
_lg.warning("Rsync, excluding unsupported entry (%s): %s",
|
|
src_kind, rel_path)
|
|
# dst_entry may exist here (e.g. inherited via hardlink from
|
|
# the previous snapshot); an excluded entry must not linger.
|
|
if not dry_run:
|
|
try:
|
|
rm_direntry(dst_entry)
|
|
except OSError as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
continue
|
|
yield rel_path, Actions.EXCLUDE, src_kind
|
|
continue
|
|
|
|
# rewrite dst if it has different type from src
|
|
if src_entry.is_file(follow_symlinks=False):
|
|
if not dst_entry.is_file(follow_symlinks=False):
|
|
_lg.debug("Rsync, rewriting"
|
|
" (src is a file, dst is not a file): %s",
|
|
rel_path)
|
|
try:
|
|
digest = update_direntry(src_entry, dst_entry)
|
|
yield rel_path, Actions.REWRITE, digest or ""
|
|
except (OSError, BackupCreationError) as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
continue
|
|
|
|
if src_entry.is_dir(follow_symlinks=False):
|
|
if not dst_entry.is_dir(follow_symlinks=False):
|
|
_lg.debug("Rsync, rewriting"
|
|
" (src is a dir, dst is not a dir): %s",
|
|
rel_path)
|
|
try:
|
|
update_direntry(src_entry, dst_entry)
|
|
yield rel_path, Actions.REWRITE, ""
|
|
except (OSError, BackupCreationError) as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
continue
|
|
|
|
if src_entry.is_symlink():
|
|
if not dst_entry.is_symlink():
|
|
_lg.debug("Rsync, rewriting"
|
|
" (src is a symlink, dst is not a symlink): %s",
|
|
rel_path)
|
|
try:
|
|
update_direntry(src_entry, dst_entry)
|
|
yield rel_path, Actions.REWRITE, ""
|
|
except (OSError, BackupCreationError) as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
continue
|
|
|
|
# rewrite dst if it is hard link to src (bad for backups)
|
|
if src_entry.inode() == dst_entry.inode():
|
|
_lg.debug("Rsync, rewriting (shared inode with src): %s", rel_path)
|
|
try:
|
|
digest = update_direntry(src_entry, dst_entry)
|
|
yield rel_path, Actions.REWRITE, digest or ""
|
|
except (OSError, BackupCreationError) as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
continue
|
|
|
|
src_stat = src_entry.stat(follow_symlinks=False)
|
|
dst_stat = dst_entry.stat(follow_symlinks=False)
|
|
|
|
# rewrite dst file/symlink which have different size or mtime than src
|
|
if src_entry.is_file(follow_symlinks=False):
|
|
same_size = src_stat.st_size == dst_stat.st_size
|
|
same_mtime = src_stat.st_mtime_ns == dst_stat.st_mtime_ns
|
|
if not (same_size and same_mtime):
|
|
reason = "size" if not same_size else "time"
|
|
_lg.debug("Rsync, rewriting (different %s): %s",
|
|
reason, rel_path)
|
|
try:
|
|
digest = update_direntry(src_entry, dst_entry)
|
|
yield rel_path, Actions.REWRITE, digest or ""
|
|
except (OSError, BackupCreationError) as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
continue
|
|
|
|
# rewrite dst symlink if it points somewhere else than src
|
|
if src_entry.is_symlink():
|
|
if os.readlink(src_entry.path) != os.readlink(dst_entry.path):
|
|
_lg.debug("Rsync, rewriting (different symlink target): %s",
|
|
rel_path)
|
|
try:
|
|
update_direntry(src_entry, dst_entry)
|
|
yield rel_path, Actions.REWRITE, ""
|
|
except (OSError, BackupCreationError) as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
continue
|
|
|
|
# Symlinks reaching here already have a matching target (handled
|
|
# above), and applying chmod/chown to a symlink path without
|
|
# follow_symlinks=False support would silently modify whatever
|
|
# the symlink points to - including a target outside the backup
|
|
# entirely. There's nothing meaningful left to sync for them.
|
|
if src_entry.is_symlink():
|
|
continue
|
|
|
|
# A regular file reaching here is unchanged in content, but may
|
|
# still be hardlinked to the same file in the previous, supposedly
|
|
# immutable snapshot (hardlink_dir() links unchanged files in at
|
|
# the start of every backup to save space). Break that link
|
|
# before mutating permissions/ownership in place, or the change
|
|
# would silently apply to every older snapshot sharing the inode.
|
|
if src_entry.is_file(follow_symlinks=False):
|
|
if src_stat.st_mode != dst_stat.st_mode or (
|
|
src_stat.st_uid != dst_stat.st_uid
|
|
or src_stat.st_gid != dst_stat.st_gid):
|
|
_break_shared_hardlink(dst_entry.path)
|
|
|
|
# update permissions and ownership
|
|
if src_stat.st_mode != dst_stat.st_mode:
|
|
_lg.debug("Rsync, updating permissions: %s", rel_path)
|
|
os.chmod(dst_entry.path, src_stat.st_mode)
|
|
yield rel_path, Actions.UPDATE_PERM, ""
|
|
|
|
if (src_stat.st_uid != dst_stat.st_uid
|
|
or src_stat.st_gid != dst_stat.st_gid):
|
|
_lg.debug("Rsync, updating owners: %s", rel_path)
|
|
try:
|
|
os.chown(dst_entry.path, src_stat.st_uid, src_stat.st_gid)
|
|
yield rel_path, Actions.UPDATE_OWNER, ""
|
|
except PermissionError:
|
|
_lg.debug("Cannot change ownership (not root): %s", rel_path)
|
|
|
|
# process remained source entries (new files/dirs/symlinks)
|
|
for rel_path, src_entry in src_files_map.items():
|
|
src_kind = entry_kind(src_entry)
|
|
if src_kind not in _SUPPORTED_KINDS:
|
|
_lg.warning("Rsync, excluding unsupported entry (%s): %s",
|
|
src_kind, rel_path)
|
|
yield rel_path, Actions.EXCLUDE, src_kind
|
|
continue
|
|
|
|
dst_path = os.path.join(dst_root_abs, rel_path)
|
|
_lg.debug("Rsync, creating: %s", rel_path)
|
|
try:
|
|
digest = copy_direntry(src_entry, dst_path)
|
|
yield rel_path, Actions.CREATE, digest or ""
|
|
except (OSError, BackupCreationError) as exc:
|
|
yield rel_path, Actions.ERROR, str(exc)
|
|
|
|
# restore dir mtimes in dst, updated by updating files
|
|
for src_entry in scantree(src_root_abs, dir_first=True,
|
|
one_filesystem=True):
|
|
if not src_entry.is_dir(follow_symlinks=False):
|
|
continue
|
|
rel_path = src_entry.path[len(src_root_abs) + 1:]
|
|
dst_path = os.path.join(dst_root_abs, rel_path)
|
|
src_stat = src_entry.stat(follow_symlinks=False)
|
|
dst_stat = os.lstat(dst_path)
|
|
if src_stat.st_mtime_ns != dst_stat.st_mtime_ns:
|
|
_lg.debug("Rsync, restoring directory mtime: %s", dst_path)
|
|
os.utime(dst_path,
|
|
ns=(src_stat.st_atime_ns, src_stat.st_mtime_ns),
|
|
follow_symlinks=False)
|
|
|
|
# restore dst_root dir mtime
|
|
src_root_stat = os.lstat(src_root_abs)
|
|
dst_root_stat = os.lstat(dst_root_abs)
|
|
if src_root_stat.st_mtime_ns != dst_root_stat.st_mtime_ns:
|
|
_lg.debug("Rsync, restoring root directory mtime: %s", dst_root_abs)
|
|
os.utime(dst_root_abs,
|
|
ns=(src_root_stat.st_atime_ns, src_root_stat.st_mtime_ns),
|
|
follow_symlinks=False)
|
|
|
|
|
|
def _recursive_hardlink_ext(src: str, dst: str) -> bool:
|
|
"""
|
|
Make hardlink for a directory using cp -al. Both src and dst should exist.
|
|
:param src: absolute path to source directory.
|
|
:param dst: absolute path to target directory.
|
|
:return: success or not
|
|
"""
|
|
if sys.platform == "darwin":
|
|
cp = "gcp"
|
|
else:
|
|
cp = "cp"
|
|
src_content = glob.glob(f"{src}/*")
|
|
cmd = [cp, "--archive", "--verbose", "--link", *src_content, dst]
|
|
_lg.info("Executing external command: %s", " ".join(cmd))
|
|
process = subprocess.Popen(cmd,
|
|
stdout=subprocess.PIPE,
|
|
stderr=subprocess.STDOUT)
|
|
with process.stdout:
|
|
for line in iter(process.stdout.readline, b""):
|
|
_lg.debug("%s: %s", cp, line.decode("utf-8").strip())
|
|
exitcode = process.wait()
|
|
return not bool(exitcode)
|
|
|
|
|
|
def _recursive_hardlink(src: str, dst: str) -> bool:
|
|
"""
|
|
Do hardlink directory recursively using python only.
|
|
Both src and dst directories should exist.
|
|
:param src: absolute path to source directory.
|
|
:param dst: absolute path to target directory.
|
|
:return: True if success, False otherwise.
|
|
"""
|
|
with os.scandir(src) as it:
|
|
ent: os.DirEntry
|
|
for ent in it:
|
|
ent_dst_path = os.path.join(dst, ent.name)
|
|
if ent.is_dir(follow_symlinks=False):
|
|
_lg.debug("Hardlink, copying directory: %s -> %s",
|
|
ent.path, ent_dst_path)
|
|
os.mkdir(ent_dst_path)
|
|
|
|
# process directory children
|
|
_recursive_hardlink(ent.path, ent_dst_path)
|
|
|
|
# save directory's metainfo
|
|
ent_stat = ent.stat(follow_symlinks=False)
|
|
try:
|
|
os.chown(ent_dst_path, ent_stat.st_uid, ent_stat.st_gid)
|
|
except PermissionError:
|
|
_lg.debug("Cannot change ownership (not root): %s", ent_dst_path)
|
|
os.chmod(ent_dst_path, ent_stat.st_mode)
|
|
os.utime(ent_dst_path,
|
|
ns=(ent_stat.st_atime_ns, ent_stat.st_mtime_ns))
|
|
|
|
continue
|
|
if ent.is_file(follow_symlinks=False) or ent.is_symlink():
|
|
_lg.debug("Hardlink, creating link for file: %s -> %s",
|
|
ent.path, ent_dst_path)
|
|
os.link(ent.path, ent_dst_path, follow_symlinks=False)
|
|
continue
|
|
# something that is not a file, symlink or directory
|
|
raise NotImplementedError(ent.path)
|
|
|
|
return True
|
|
|
|
|
|
def hardlink_dir(src_dir, dst_dir, use_external: bool = False) -> bool:
|
|
"""
|
|
Make hardlink for a directory with all its content.
|
|
:param src_dir: path to source directory
|
|
:param dst_dir: path to target directory
|
|
:param use_external: whether to use external cp -al command
|
|
:return: True if success, False otherwise.
|
|
"""
|
|
_lg.debug("Recursive hardlinking: %s -> %s", src_dir, dst_dir)
|
|
src_abs = os.path.abspath(src_dir)
|
|
dst_abs = os.path.abspath(dst_dir)
|
|
|
|
if not os.path.isdir(src_abs):
|
|
raise RuntimeError(f"Error reading source directory: {src_dir}")
|
|
if os.path.exists(dst_abs):
|
|
raise RuntimeError(f"Destination already exists: {dst_dir}")
|
|
_lg.debug("Hardlink, creating directory: %s", dst_abs)
|
|
os.mkdir(dst_abs)
|
|
|
|
hardlink_func = (_recursive_hardlink_ext if use_external
|
|
else _recursive_hardlink)
|
|
return hardlink_func(src_abs, dst_abs)
|
|
|
|
|
|
def nest_hardlink(src_dir: str, src_relpath: str, dst_dir: str):
|
|
"""
|
|
Hardlink entity from (src_dir + src_relpath) to dst_dir preserving dir
|
|
structure of src_relpath.
|
|
"""
|
|
_lg.debug("Nested hardlinking: %s%s%s -> %s",
|
|
src_dir, os.path.sep, src_relpath, dst_dir)
|
|
if os.path.isabs(src_relpath) or os.path.pardir in src_relpath.split(
|
|
os.path.sep):
|
|
raise RuntimeError(
|
|
"Refusing non-normalized relative path: %s" % src_relpath)
|
|
|
|
src_dir_abs = os.path.abspath(src_dir)
|
|
src_full_path = os.path.join(src_dir_abs, src_relpath)
|
|
dst_dir_abs = os.path.abspath(dst_dir)
|
|
dst_full_path = os.path.join(dst_dir_abs, src_relpath)
|
|
|
|
# check source entity and destination directory
|
|
if not os.path.lexists(src_full_path):
|
|
raise RuntimeError("Error reading source entity: %s" % src_full_path)
|
|
if os.path.lexists(dst_dir_abs):
|
|
if not os.path.isdir(dst_dir_abs):
|
|
raise RuntimeError("Destination path is not a directory: %s"
|
|
% dst_dir_abs)
|
|
else:
|
|
os.mkdir(dst_dir_abs)
|
|
|
|
# if destination entity exists, check it points to source entity
|
|
dst_entry = PseudoDirEntry(dst_full_path)
|
|
if os.path.lexists(dst_entry.path):
|
|
src_stat = os.lstat(src_full_path)
|
|
if os.path.samestat(src_stat, dst_entry.stat()):
|
|
return
|
|
# remove otherwise
|
|
rm_direntry(dst_entry)
|
|
|
|
src_cur_path = src_dir_abs
|
|
dst_cur_path = dst_dir_abs
|
|
for rel_part in src_relpath.split(sep=os.path.sep):
|
|
src_cur_path = os.path.join(src_cur_path, rel_part)
|
|
dst_cur_path = os.path.join(dst_cur_path, rel_part)
|
|
if os.path.exists(dst_cur_path):
|
|
continue
|
|
copy_direntry(PseudoDirEntry(src_cur_path), dst_cur_path)
|