Bump version to 4.2.0

Use git.shouldnt.work as the clone URL, don't install wheel for
building, as setuptools no longer needs it, list paramiko among the
optional dependencies, and use the correct names of the remote
backup options (--ssh-user, --ssh-host).

PKGBUILD

@@ -0,0 +1,38 @@
+# PKGBUILD
+
+# Maintainer: Daniele Fucini <dfucini [at] gmail [dot] com>
+
+pkgname=simple_backup
+pkgdesc='Simple backup script that uses rsync to copy files'
+pkgver=4.1.7
+pkgrel=1
+url="https://git.shouldnt.work/fuxino/${pkgname}"
+arch=('any')
+license=('GPL-3.0-or-later')
+makedepends=('git'
+             'python-setuptools'
+             'python-build'
+             'python-installer')
+depends=('python>=3.10'
+         'rsync')
+optdepends=('python-systemd: use systemd log'
+            'python-dbus: for desktop notifications'
+            'python-paramiko: for remote backup through ssh')
+conflicts=('simple_backup-git')
+source=(git+${url}?signed#tag=${pkgver})
+validpgpkeys=('7E12BC1FF3B6EDB2CD8053EB981A2B2A3BBF5514')
+sha256sums=('011cd5546745e413ac7603b64531def2688c2bf6e4ea19876a67547a1db208ce')
+
+build()
+{
+    cd ${srcdir}/${pkgname}
+    python -m build --wheel --no-isolation
+}
+
+package()
+{
+    cd ${srcdir}/${pkgname}
+    python -m installer --destdir=${pkgdir} dist/*.whl
+    install -Dm644 ${pkgname}/${pkgname}.conf ${pkgdir}/usr/share/doc/${pkgname}/${pkgname}.conf
+    install -Dm644 man/${pkgname}.1 ${pkgdir}/usr/share/man/man1/${pkgname}.1
+}

README.md

@@ -20,21 +20,19 @@ The script uses rsync to actually run the backup, so you will have to install it
 sudo pacman -Syu rsync
 ```
 
-It's also required to have python-dotenv
+Optional dependencies are systemd-python to enable using systemd journal for logging, dbus-python for desktop notifications, and paramiko for remote backup.
-
-Optional dependencies are systemd-python to enable using systemd journal for logging, and dbus-python for desktop notifications.
 
 ## Install
 To install the program, first clone the repository:
 
 ```bash
-git clone https://github.com/Fuxino/simple_backup.git
+git clone https://git.shouldnt.work/fuxino/simple_backup.git
 ```
 
 Then install the tools required to build the package:
 
 ```bash
-pip install --upgrade build wheel
+pip install --upgrade build
 ```
 
 Finally, run:
@@ -49,11 +47,16 @@ For Arch Linux and Arch-based distros, two packages are available in the AUR (au
 - **simple_backup** for the release version
 - **simple_backup-git** for the git version
 
+## Old backups
+The number of old backups to keep can be set with the --keep (or -k) argument (or in the configuration file).
+Old backups are only removed if rsync completes successfully, so that they are not deleted when the new backup may be incomplete.
+The only rsync error that is ignored is return code 24 (source files vanished during the transfer), which is common when backing up a live system.
+
 ## Remote backup
 > **Warning**
 > This feature is experimental
 
-It's possible to use a remote server as destination for the backup. Just use the --username (or -u) and --host arguments (or set them in the configuration file).
+It's possible to use a remote server as destination for the backup. Just use the --ssh-user and --ssh-host arguments (or set them in the configuration file).
 For this to work, rsync must be installed on the server too.
 
 ### Server authentication

man/simple_backup.1

@@ -1,4 +1,4 @@
-.TH SIMPLE_BACKUP 1 2023-06-15 SIMPLE_BACKUP 3.2.6
+.TH SIMPLE_BACKUP 1 2026-10-08 SIMPLE_BACKUP 4.2.0
 .SH NAME
 simple_backup \- Backup files and folders using rsync
 .SH SYNOPSIS
@@ -52,7 +52,15 @@ or to use single or double quotes around them.
 .B \-o, \-\-output DIR
 Specify the directory where the files will be copied. The program will automatically
 create a subdirectory called \(aqsimple_backup\(aq (if it does not already exist) and
-inside this directory the actual backup directory (using the current date and time).
+inside this directory the actual backup directory (using the current date and time, for example
+\(aq2026\-10\-08_17\-34\-47\(aq).
+.RS
+.P
+Backups are best stored on a Linux filesystem (e.g. ext4 or btrfs). FAT and exFAT filesystems
+are supported, but they don\(aqt support hard links, so each backup will be a full copy instead
+of only storing files that changed since the previous one. File ownership and permissions are
+not preserved either.
+.RE
 .TP
 .B \-e, \-\-exclude FILE|DIR|PATTERN [FILE|...]]
 Specify files, directories or patterns to exclude from the backup. Matching files and directories
@@ -61,6 +69,10 @@ will not be copied. Multiple elements can be specified, in the same way as for t
 .B \-k, \-\-keep N
 Specify how many old backups (so excluding the current one) will be kept. The default behavior
 is to keep them all (same as N=\-1).
+Old backups are only removed if rsync completes successfully, to avoid deleting them when the
+new backup may be incomplete. rsync return code 24 (source files vanished during the transfer)
+is treated as success, while any other error (including return code 23, partial transfer due to error)
+will prevent old backups from being removed. This does not apply when using \-\-remove\-before\-backup.
 .TP
 .B \-u, \-\-user USERNAME
 Explicitly specify the user running the backup (in case it is needed for home directory expansion).
@@ -86,6 +98,9 @@ if saving bandwith is needed.
 Remove old backups (if necessary) before creating the new backup. Useful to free some space
 before performing the backup.
 Default behavior is to remove old backups after successfully completing the backup.
+Note that if the backup fails after old backups have been removed, only the backups kept
+according to \-\-keep will be left, and the new backup may be incomplete. In particular, with
+\-\-keep 0 there will be no complete backup available until the next successful one.
 .TP
 .B \-\-no\-syslog
 Don't use systemd journal for logging.
@@ -100,7 +115,7 @@ Using \-\-rsync\-options it is possible to manually select which options to use.
 .P
     \-a, \-l, \-p, \-t, \-g, \-o, \-c, \-h, \-D, \-H, \-X, \-s
 .P
-Options \-r and \-v are used in any case. Not that options must be specified without dash (\-), for example:
+Options \-r, \-v, \-\-ignore\-missing\-args and \-\-mkpath are used in any case. Note that options must be specified without dash (\-), for example:
 .P
 .EX
     simple_backup \-\-rsync\-options a l p
@@ -187,6 +202,6 @@ Bad configuration file.
 .SH SEE ALSO
 .BR rsync (1)
 .SH AUTHORS
-.MT https://github.com/Fuxino
+.MT https://git.shouldnt.work/fuxino
 Daniele Fucini
 .ME

pyproject.toml

@@ -1,3 +1,48 @@
 [build-system]
-requires = ['setuptools']
+requires = ['setuptools>=77']
 build-backend = 'setuptools.build_meta'
+
+[project]
+name = "simple_backup"
+dynamic = ["version"]
+description = "Simple backup script that uses rsync to copy files"
+readme = "README.md"
+requires-python = ">=3.10"
+license = "GPL-3.0-or-later"
+license-files = ["LICENSE"]
+authors = [
+  { name = "Daniele Fucini", email = "dfucini@gmail.com" }
+]
+maintainers = [
+  { name = "Daniele Fucini", email = "dfucini@gmail.com" }
+]
+classifiers = [
+  "Development Status :: 4 - Beta",
+  "Environment :: Console",
+  "Natural Language :: English",
+  "Operating System :: POSIX :: Linux",
+  "Programming Language :: Python :: 3",
+  "Programming Language :: Python :: 3.10",
+  "Programming Language :: Python :: 3.11",
+  "Programming Language :: Python :: 3.12",
+  "Programming Language :: Python :: 3.13",
+  "Programming Language :: Python :: 3.14",
+  "Topic :: System :: Archiving :: Backup",
+]
+
+[project.optional-dependencies]
+JOURNAL = ["systemd-python"]
+NOTIFICATIONS = ["dbus-python"]
+REMOTE = ["paramiko"]
+
+[project.urls]
+Homepage = "https://git.shouldnt.work/fuxino/simple_backup"
+
+[project.scripts]
+simple_backup = "simple_backup.simple_backup:simple_backup"
+
+[tool.setuptools]
+packages = ["simple_backup"]
+
+[tool.setuptools.dynamic]
+version = { attr = "simple_backup.__version__" }

setup.cfg

@@ -1,38 +0,0 @@
-[metadata]
-name = simple_backup
-version = attr: simple_backup.__version__
-description = Simple backup script using rsync
-long_description = file: README.md
-author = Daniele Fucini
-author_email = dfucini@gmail.com
-license = GPL3
-url = https://github.com/Fuxino/simple_backup
-classifiers =
-   Development Status :: 4 - Beta
-   Environment :: Console
-   License :: OSI Approved :: GNU General Public License v3 (GPLv3)
-   Natural Language :: English
-   Operating System :: POSIX :: Linux
-   Programming Language :: Python :: 3.10
-   Programming Language :: Python :: 3.11
-   Programming Language :: Python :: 3.12
-   Topic :: System :: Archiving :: Backup
-
-[options]
-packages = simple_backup
-python_requires = >=3.10
-install_requires =
-   python-dotenv
-
-[options.extras_require]
-JOURNAL =
-    systemd-python
-NOTIFICATIONS =
-    dbus-python
-REMOTE =
-    paramiko
-
-[options.entry_points]
-console_scripts =
-   simple_backup = simple_backup.simple_backup:simple_backup
-

simple_backup/__init__.py

@@ -1,3 +1,3 @@
 """Init."""
 
-__version__ = '4.1.5'
+__version__ = '4.2.0'

simple_backup/simple_backup.py

@@ -11,9 +11,13 @@ Classes:
     Backup
 """
 
+# Avoid evaluating annotations at definition time, as they reference optional modules (paramiko)
+from __future__ import annotations
+
 # Import libraries
 import sys
 import os
+import pwd
 from typing import Callable, List, Optional, ParamSpec, TypeVar, Union
 import warnings
 from functools import wraps
@@ -30,10 +34,6 @@ from tempfile import mkstemp
 from getpass import GetPassWarning, getpass
 from glob import glob
 
-from dotenv import load_dotenv
-
-warnings.filterwarnings('error')
-
 try:
     import paramiko
     from paramiko import RSAKey, Ed25519Key, ECDSAKey, DSSKey
@@ -48,10 +48,9 @@ except ImportError:
 try:
     import dbus
 except ImportError:
-    pass
+    dbus = None
 
 
-load_dotenv()
 logging.getLogger().setLevel(logging.DEBUG)
 logger = logging.getLogger(os.path.basename(__file__))
 c_handler = StreamHandler()
@@ -158,17 +157,20 @@ class Backup:
         self._ssh = None
         self._password_auth = False
         self._password = None
+        self._removed_count = 0
 
     def check_params(self, homedir: str = '') -> int:
         """Check if parameters for the backup are valid"""
 
         if self.inputs is None or len(self.inputs) == 0:
-            logger.info('No existing files or directories specified for backup. Nothing to do')
+            logger.info(
+                'No existing files or directories specified for backup. Nothing to do')
 
             return 1
 
         if self.output is None:
-            logger.critical('No output path specified. Use -o argument or specify output path in configuration file')
+            logger.critical(
+                'No output path specified. Use -o argument or specify output path in configuration file')
 
             return 2
 
@@ -181,7 +183,8 @@ class Backup:
             if self._ssh is None:
                 return 5
 
-            _, stdout, _ = self._ssh.exec_command(f'if [ -d "{self.output}" ]; then echo "ok"; fi')
+            _, stdout, _ = self._ssh.exec_command(
+                f'if [ -d "{self.output}" ]; then echo "ok"; fi')
 
             output = stdout.read().decode('utf-8').strip()
 
@@ -205,7 +208,9 @@ class Backup:
     # Function to create the actual backup directory
     def define_backup_dir(self) -> None:
         """Define the actual backup dir"""
-        now = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
+        # Avoid ':', which is not allowed on FAT/exFAT filesystems.
+        # Backups created with the old format ('%Y-%m-%d %H:%M:%S') still sort correctly
+        now = datetime.now().strftime('%Y-%m-%d_%H-%M-%S')
         self._output_dir = f'{self.output}/simple_backup/{now}'
 
         if self._remote:
@@ -217,7 +222,8 @@ class Backup:
         if self._remote:
             assert self._ssh is not None
 
-            _, stdout, _ = self._ssh.exec_command(f'ls {self.output}/simple_backup')
+            _, stdout, _ = self._ssh.exec_command(
+                f'ls {self.output}/simple_backup')
 
             dirs = stdout.read().decode('utf-8').strip().split('\n')
 
@@ -234,14 +240,17 @@ class Backup:
 
                 for i in range(n_backup - self.keep):
                     if self.remote_sudo:
-                        _, _, stderr = self._ssh.exec_command(f'sudo rm -r "{self.output}/simple_backup/{dirs[i]}"')
+                        _, _, stderr = self._ssh.exec_command(
+                            f'sudo rm -r "{self.output}/simple_backup/{dirs[i]}"')
                     else:
-                        _, _, stderr = self._ssh.exec_command(f'rm -r "{self.output}/simple_backup/{dirs[i]}"')
+                        _, _, stderr = self._ssh.exec_command(
+                            f'rm -r "{self.output}/simple_backup/{dirs[i]}"')
 
                     err = stderr.read().decode('utf-8').strip().split('\n')[0]
 
                     if err != '':
-                        logger.error('Error while removing backup %s.', {dirs[i]})
+                        logger.error(
+                            'Error while removing backup %s.', {dirs[i]})
                         logger.error(err)
                     else:
                         count += 1
@@ -267,9 +276,13 @@ class Backup:
                         rmtree(f'{self.output}/simple_backup/{dirs[i]}')
                         count += 1
                     except FileNotFoundError:
-                        logger.error('Error while removing backup %s. Directory not found', dirs[i])
+                        logger.error(
+                            'Error while removing backup %s. Directory not found', dirs[i])
                     except PermissionError:
-                        logger.error('Error while removing backup %s. Permission denied', dirs[i])
+                        logger.error(
+                            'Error while removing backup %s. Permission denied', dirs[i])
+
+        self._removed_count = count
 
         if count == 1:
             logger.info('Removed %d backup', count)
@@ -284,7 +297,8 @@ class Backup:
                 logger.critical('SSH connection to server failed')
                 sys.exit(5)
 
-            _, stdout, _ = self._ssh.exec_command(f'find {self.output}/simple_backup/ -mindepth 1 -maxdepth 1 -type d | sort')
+            _, stdout, _ = self._ssh.exec_command(
+                f'find {self.output}/simple_backup/ -mindepth 1 -maxdepth 1 -type d | sort')
             output = stdout.read().decode('utf-8').strip().split('\n')
 
             if output[-1] != '':
@@ -293,18 +307,17 @@ class Backup:
                 logger.info('No previous backups available')
         else:
             try:
-                dirs = sorted([f.path for f in os.scandir(f'{self.output}/simple_backup') if f.is_dir(follow_symlinks=False)])
+                dirs = sorted([f.path for f in os.scandir(
+                    f'{self.output}/simple_backup') if f.is_dir(follow_symlinks=False)])
             except FileNotFoundError:
                 logger.info('No previous backups available')
 
                 return
             except PermissionError:
-                logger.critical('Cannot access the backup directory. Permission denied')
+                logger.critical(
+                    'Cannot access the backup directory. Permission denied')
 
-                try:
                 _notify('Backup failed (check log for details)')
-                except NameError:
-                    pass
 
                 sys.exit(3)
 
@@ -313,7 +326,7 @@ class Backup:
             except IndexError:
                 logger.info('No previous backups available')
 
-    def _ssh_connect(self, homedir: str = '') -> paramiko.client.SSHClient:
+    def _ssh_connect(self, homedir: str = '') -> Optional[paramiko.client.SSHClient]:
         try:
             ssh = paramiko.SSHClient()
         except NameError:
@@ -329,11 +342,15 @@ class Backup:
         ssh.set_missing_host_key_policy(paramiko.WarningPolicy())
 
         try:
+            # WarningPolicy emits a UserWarning for unknown host keys
+            with warnings.catch_warnings():
+                warnings.simplefilter('error', UserWarning)
                 ssh.connect(self.ssh_host, username=self.ssh_user)
 
             return ssh
         except UserWarning:
-            k = input(f'Unknown key for host {self.ssh_host}. Continue anyway? (Y/N) ')
+            k = input(
+                f'Unknown key for host {self.ssh_host}. Continue anyway? (Y/N) ')
 
             if k[0].upper() == 'Y':
                 ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
@@ -356,8 +373,14 @@ class Backup:
 
         if self.ssh_keyfile is None:
             try:
-                password = getpass(f'{self.ssh_user}@{self.ssh_host}\'s password: ')
+                # Fail instead of reading the password with echo if no terminal is available
-                ssh.connect(self.ssh_host, username=self.ssh_user, password=password)
+                with warnings.catch_warnings():
+                    warnings.simplefilter('error', GetPassWarning)
+                    password = getpass(
+                        f'{self.ssh_user}@{self.ssh_host}\'s password: ')
+
+                ssh.connect(self.ssh_host, username=self.ssh_user,
+                            password=password)
 
                 self._password_auth = True
                 os.environ['SSHPASS'] = password
@@ -379,7 +402,8 @@ class Backup:
         try:
             pkey = RSAKey.from_private_key_file(self.ssh_keyfile)
         except paramiko.PasswordRequiredException:
-            password = getpass(f'Enter passwphrase for key \'{self.ssh_keyfile}\': ')
+            password = getpass(
+                f'Enter passwphrase for key \'{self.ssh_keyfile}\': ')
 
             try:
                 pkey = RSAKey.from_private_key_file(self.ssh_keyfile, password)
@@ -391,7 +415,8 @@ class Backup:
                 pkey = Ed25519Key.from_private_key_file(self.ssh_keyfile)
             except paramiko.PasswordRequiredException:
                 try:
-                    pkey = Ed25519Key.from_private_key_file(self.ssh_keyfile, password)
+                    pkey = Ed25519Key.from_private_key_file(
+                        self.ssh_keyfile, password)
                 except paramiko.SSHException:
                     pass
 
@@ -400,7 +425,8 @@ class Backup:
                 pkey = ECDSAKey.from_private_key_file(self.ssh_keyfile)
             except paramiko.PasswordRequiredException:
                 try:
-                    pkey = ECDSAKey.from_private_key_file(self.ssh_keyfile, password)
+                    pkey = ECDSAKey.from_private_key_file(
+                        self.ssh_keyfile, password)
                 except paramiko.SSHException:
                     pass
 
@@ -409,7 +435,8 @@ class Backup:
                 pkey = DSSKey.from_private_key_file(self.ssh_keyfile)
             except paramiko.PasswordRequiredException:
                 try:
-                    pkey = DSSKey.from_private_key_file(self.ssh_keyfile, password)
+                    pkey = DSSKey.from_private_key_file(
+                        self.ssh_keyfile, password)
                 except paramiko.SSHException:
                     pass
 
@@ -425,72 +452,94 @@ class Backup:
     def _returncode_log(self, returncode: int) -> None:
         match returncode:
             case 2:
-                logger.error('Rsync error (return code 2) - Protocol incompatibility')
+                logger.error(
+                    'Rsync error (return code 2) - Protocol incompatibility')
             case 3:
-                logger.error('Rsync error (return code 3) - Errors selecting input/output files, dirs')
+                logger.error(
+                    'Rsync error (return code 3) - Errors selecting input/output files, dirs')
             case 4:
-                logger.error('Rsync error (return code 4) - Requested action not supported')
+                logger.error(
+                    'Rsync error (return code 4) - Requested action not supported')
             case 5:
-                logger.error('Rsync error (return code 5) - Error starting client-server protocol')
+                logger.error(
+                    'Rsync error (return code 5) - Error starting client-server protocol')
             case 10:
-                logger.error('Rsync error (return code 10) - Error in socket I/O')
+                logger.error(
+                    'Rsync error (return code 10) - Error in socket I/O')
             case 11:
-                logger.error('Rsync error (return code 11) - Error in file I/O')
+                logger.error(
+                    'Rsync error (return code 11) - Error in file I/O')
             case 12:
-                logger.error('Rsync error (return code 12) - Error in rsync protocol data stream')
+                logger.error(
+                    'Rsync error (return code 12) - Error in rsync protocol data stream')
             case 22:
-                logger.error('Rsync error (return code 22) - Error allocating core memory buffers')
+                logger.error(
+                    'Rsync error (return code 22) - Error allocating core memory buffers')
             case 23:
-                logger.warning('Rsync error (return code 23) - Partial transfer due to error')
+                logger.warning(
+                    'Rsync error (return code 23) - Partial transfer due to error')
             case 24:
-                logger.warning('Rsync error (return code 24) - Partial transfer due to vanished source files')
+                logger.warning(
+                    'Rsync error (return code 24) - Partial transfer due to vanished source files')
             case 30:
-                logger.error('Rsync error (return code 30) - Timeout in data send/receive')
+                logger.error(
+                    'Rsync error (return code 30) - Timeout in data send/receive')
             case 35:
-                logger.error('Rsync error (return code 35) - Timeout waiting for daemon connection')
+                logger.error(
+                    'Rsync error (return code 35) - Timeout waiting for daemon connection')
             case _:
-                logger.error('Rsync error (return code %d) - Check rsync(1) for details', returncode)
+                logger.error(
+                    'Rsync error (return code %d) - Check rsync(1) for details', returncode)
 
     # Function to read configuration file
     @timing
     def run(self) -> int:
         """Perform the backup"""
 
-        logger.info('Starting backup...')
-
         try:
-            _notify('Starting backup...')
+            return self._run()
-        except NameError:
+        finally:
+            self._remove_temp_files()
+
+    def _remove_temp_files(self) -> None:
+        for path in [self._inputs_path, self._exclude_path]:
+            if path != '':
+                try:
+                    os.remove(path)
+                except FileNotFoundError:
                     pass
 
-        self.define_backup_dir()
+    def _run(self) -> int:
-        self.find_last_backup()
+        logger.info('Starting backup...')
 
-        _, self._inputs_path = mkstemp(prefix='tmp_inputs', text=True)
+        _notify('Starting backup...')
+
+        self.define_backup_dir()
+
+        fd, self._inputs_path = mkstemp(prefix='tmp_inputs', text=True)
         count = 0
 
-        with open(self._inputs_path, 'w', encoding='utf-8') as fp:
+        with os.fdopen(fd, 'w', encoding='utf-8') as fp:
             for i in self.inputs:
                 if not os.path.exists(i):
                     logger.warning('Input %s not found. Skipping', i)
                 else:
-                    fp.write(i)
+                    # rsync reads --files-from paths relative to the source ('/')
+                    fp.write(os.path.abspath(i))
                     fp.write('\n')
                     count += 1
 
         if count == 0:
-            logger.info('No existing files or directories specified for backup. Nothing to do')
+            logger.info(
+                'No existing files or directories specified for backup. Nothing to do')
 
-            try:
             _notify('Backup finished. No files copied')
-            except NameError:
-                pass
 
             return 1
 
-        _, self._exclude_path = mkstemp(prefix='tmp_exclude', text=True)
+        fd, self._exclude_path = mkstemp(prefix='tmp_exclude', text=True)
 
-        with open(self._exclude_path, 'w', encoding='utf-8') as fp:
+        with os.fdopen(fd, 'w', encoding='utf-8') as fp:
             if self.exclude is not None:
                 for e in self.exclude:
                     fp.write(e)
@@ -499,6 +548,9 @@ class Backup:
         if self.keep != -1 and self._remove_before:
             self.remove_old_backups()
 
+        # Only look for the last backup now, as it may have been removed above
+        self.find_last_backup()
+
         logger.info('Copying files. This may take a long time...')
 
         if self._last_backup == '':
@@ -550,92 +602,106 @@ class Backup:
                 else:
                     logger.error(output)
 
-        if self.keep != -1 and not self._remove_before:
+        if self._removed_count > 0 and returncode not in [0, 24]:
-            self.remove_old_backups()
+            # With --remove-before-backup, old backups are already gone if the new one failed
+            if self.keep == 0:
+                message = 'All old backups were removed before the backup, and the new backup may be ' +\
+                    'incomplete. No complete backup is available'
+            else:
+                message = 'Old backups were removed before the backup, and the new backup may be incomplete'
 
-        os.remove(self._inputs_path)
+            logger.error(message)
-        os.remove(self._exclude_path)
+            _notify(message)
+
+        if self.keep != -1 and not self._remove_before:
+            # Don't delete old backups if the new one may be incomplete
+            if returncode in [0, 24]:
+                self.remove_old_backups()
+            else:
+                logger.warning('Backup not completed successfully. Old backups will not be removed')
 
         if self._remote:
             assert self._ssh is not None
 
-            _, stdout, _ = self._ssh.exec_command(f'if [ -d "{self._output_dir}" ]; then echo "ok"; fi')
+            _, stdout, _ = self._ssh.exec_command(
+                f'if [ -d "{self._output_dir}" ]; then echo "ok"; fi')
 
             output = stdout.read().decode('utf-8').strip()
 
             if output == 'ok':
                 logger.info('Backup completed')
 
-                try:
                 _notify('Backup completed')
-                except NameError:
-                    pass
             else:
                 logger.error('Backup failed')
 
-                try:
                 _notify('Backup failed (check log for details)')
-                except NameError:
-                    pass
 
             if self._ssh:
                 self._ssh.close()
         else:
             if returncode != 0:
-                logger.error('Some errors occurred while performing the backup')
+                logger.error(
+                    'Some errors occurred while performing the backup')
 
-                try:
+                _notify(
-                    _notify('Some errors occurred while performing the backup. Check log for details')
+                    'Some errors occurred while performing the backup. Check log for details')
-                except NameError:
-                    pass
 
                 return 4
 
             logger.info('Backup completed')
 
-            try:
             _notify('Backup completed')
-            except NameError:
-                pass
 
             return 0
 
 
-def _parse_arguments():
+def _detect_user() -> Optional[str]:
-    euid = os.geteuid()
+    if os.geteuid() == 0:
+        return os.getenv('SUDO_USER') or os.getenv('DOAS_USER')
 
-    if euid == 0:
+    return os.getenv('USER')
-        user = os.getenv('SUDO_USER')
-    else:
-        user = os.getenv('USER')
 
-    homedir = os.path.expanduser(f'~{user}')
 
+def _parse_arguments() -> argparse.Namespace:
     parser = argparse.ArgumentParser(prog='simple_backup',
                                      description='Simple backup script written in Python that uses rsync to copy files',
                                      epilog='See simple_backup(1) manpage for full documentation',
                                      formatter_class=MyFormatter)
 
-    parser.add_argument('-v', '--verbose', action='store_true', help='More verbose output')
+    parser.add_argument('-v', '--verbose', action='store_true',
-    parser.add_argument('-c', '--config', default=f'{homedir}/.config/simple_backup/simple_backup.conf',
+                        help='More verbose output')
+    parser.add_argument('-c', '--config', default='~/.config/simple_backup/simple_backup.conf',
                         help='Specify location of configuration file')
-    parser.add_argument('-i', '--inputs', nargs='+', help='Paths/files to backup')
+    parser.add_argument('-i', '--inputs', nargs='+',
-    parser.add_argument('-o', '--output', help='Output directory for the backup')
+                        help='Paths/files to backup')
-    parser.add_argument('-e', '--exclude', nargs='+', help='Files/directories/patterns to exclude from the backup')
+    parser.add_argument(
-    parser.add_argument('-k', '--keep', type=int, help='Number of old backups to keep')
+        '-o', '--output', help='Output directory for the backup')
-    parser.add_argument('-u', '--user', help='Explicitly specify the user running the backup')
+    parser.add_argument('-e', '--exclude', nargs='+',
-    parser.add_argument('-s', '--checksum', action='store_true', help='Use checksum rsync option to compare files')
+                        help='Files/directories/patterns to exclude from the backup')
-    parser.add_argument('--ssh-host', help='Server hostname (for remote backup)')
+    parser.add_argument('-k', '--keep', type=int,
-    parser.add_argument('--ssh-user', help='Username to connect to server (for remote backup)')
+                        help='Number of old backups to keep')
+    parser.add_argument(
+        '-u', '--user', help='Explicitly specify the user running the backup')
+    parser.add_argument('-s', '--checksum', action='store_true',
+                        help='Use checksum rsync option to compare files')
+    parser.add_argument(
+        '--ssh-host', help='Server hostname (for remote backup)')
+    parser.add_argument(
+        '--ssh-user', help='Username to connect to server (for remote backup)')
     parser.add_argument('--keyfile', help='SSH key location')
-    parser.add_argument('-z', '--compress', action='store_true', help='Compress data during the transfer')
+    parser.add_argument('-z', '--compress', action='store_true',
+                        help='Compress data during the transfer')
     parser.add_argument('--remove-before-backup', action='store_true',
                         help='Remove old backups before executing the backup, instead of after')
-    parser.add_argument('--no-syslog', action='store_true', help='Disable systemd journal logging')
+    parser.add_argument('--no-syslog', action='store_true',
+                        help='Disable systemd journal logging')
     parser.add_argument('--rsync-options', nargs='+',
-                        choices=['a', 'l', 'p', 't', 'g', 'o', 'c', 'h', 's', 'D', 'H', 'X'],
+                        choices=['a', 'l', 'p', 't', 'g', 'o',
+                                 'c', 'h', 's', 'D', 'H', 'X'],
                         help='Specify options for rsync')
-    parser.add_argument('--remote-sudo', action='store_true', help='Run rsync on remote server with sudo if allowed')
+    parser.add_argument('--remote-sudo', action='store_true',
+                        help='Run rsync on remote server with sudo if allowed')
     parser.add_argument('--numeric-ids', action='store_true',
                         help='Use rsync \'--numeric-ids\' option (don\'t map uid/gid values by name)')
 
@@ -644,7 +710,16 @@ def _parse_arguments():
     return args
 
 
-def _expand_inputs(inputs, user=None):
+def _expand_home(path: str, user: str) -> str:
+    """Expand a leading '~' to the home directory of user (other '~' are left as they are)"""
+
+    if path == '~' or path.startswith('~/'):
+        path = f'~{user}{path[1:]}'
+
+    return os.path.expanduser(path)
+
+
+def _expand_inputs(inputs, user: Optional[str] = None):
     expanded_inputs = []
 
     for i in inputs:
@@ -652,22 +727,23 @@ def _expand_inputs(inputs, user=None):
             continue
 
         if user is not None:
-            i_ex = glob(os.path.expanduser(i.replace('~', f'~{user}')))
+            i_ex = glob(_expand_home(i, user))
         else:
             i_ex = glob(i)
 
-            if '~' in i:
+            if i.startswith('~'):
                 logger.warning('Cannot expand \'~\'. No user specified')
 
         if len(i_ex) == 0:
-            logger.warning('No file or directory matching input %s. Skipping...', i)
+            logger.warning(
+                'No file or directory matching input %s. Skipping...', i)
         else:
             expanded_inputs.extend(i_ex)
 
     return expanded_inputs
 
 
-def _read_config(config_file, user=None):
+def _read_config(config_file, user: Optional[str] = None):
     config_args = {'inputs': None,
                    'output': None,
                    'exclude': None,
@@ -679,11 +755,16 @@ def _read_config(config_file, user=None):
                    'numeric_ids': False}
 
     if not os.path.isfile(config_file):
+        if user is not None:
             logger.warning('Config file %s does not exist', config_file)
+        else:
+            logger.warning(
+                'User not specified. Can\'t read configuration file')
 
         return config_args
 
-    config = configparser.ConfigParser()
+    # Disable interpolation, so that '%' can be used in paths and patterns
+    config = configparser.ConfigParser(interpolation=None)
     config.read(config_file)
 
     section = 'backup'
@@ -695,7 +776,7 @@ def _read_config(config_file, user=None):
         section = 'default'
         inputs = config.get(section, 'inputs')
 
-    inputs = inputs.split(',')
+    inputs = [i.strip() for i in inputs.split(',')]
     inputs = _expand_inputs(inputs, user)
     inputs = list(set(inputs))
 
@@ -704,15 +785,15 @@ def _read_config(config_file, user=None):
     output = config.get(section, 'backup_dir')
 
     if user is not None:
-        output = os.path.expanduser(output.replace('~', f'~{user}'))
+        output = _expand_home(output, user)
-    elif user is None and '~' in output:
+    elif user is None and output.startswith('~'):
         logger.warning('Cannot expand \'~\', no user specified')
 
     config_args['output'] = output
 
     try:
         exclude = config.get(section, 'exclude')
-        exclude = exclude.split(',')
+        exclude = [e.strip() for e in exclude.split(',') if e.strip() != '']
     except configparser.NoOptionError:
         exclude = []
 
@@ -759,28 +840,59 @@ def _read_config(config_file, user=None):
     return config_args
 
 
-def _notify(text):
+def _target_uid() -> int | None:
     euid = os.geteuid()
 
-    if euid == 0:
+    if euid != 0:
-        uid = os.getenv('SUDO_UID')
+        return euid
-    else:
-        uid = euid
 
-    if uid is None:
+    if (val := os.getenv('SUDO_UID')) is not None:
+        return int(val)
+
+    if (name := os.getenv('DOAS_USER')) is not None:
+        try:
+            return pwd.getpwnam(name).pw_uid
+        except KeyError:
+            return None
+
+    return None
+
+
+_notify_failed = False
+
+
+def _notify(text: str) -> None:
+    global _notify_failed
+
+    if dbus is None or _notify_failed:
         return
 
-    os.seteuid(int(uid))
+    euid = os.geteuid()
+    uid = _target_uid()
+
+    if uid is None:
+        logger.debug('Cannot send desktop notification: user not found')
+
+        return
+
+    os.seteuid(uid)
+
+    try:
         os.environ['DBUS_SESSION_BUS_ADDRESS'] = f'unix:path=/run/user/{uid}/bus'
 
-    obj = dbus.SessionBus().get_object('org.freedesktop.Notifications', '/org/freedesktop/Notifications')
+        obj = dbus.SessionBus().get_object('org.freedesktop.Notifications',
+                                           '/org/freedesktop/Notifications')
         obj = dbus.Interface(obj, 'org.freedesktop.Notifications')
-    obj.Notify('', 0, '', 'simple_backup', text, [], {'urgency': 1}, 10000)
+        obj.Notify('simple_backup', 0, '', 'simple_backup', text, [], {'urgency': dbus.Byte(1)}, 10000)
-
+    except Exception as e:
-    os.seteuid(int(euid))
+        # Report the failure only once (e.g. no session bus available), then stop trying
+        _notify_failed = True
+        logger.warning('Cannot send desktop notification: %s', e)
+    finally:
+        os.seteuid(euid)
 
 
-def simple_backup():
+def simple_backup() -> int:
     """Main"""
 
     args = _parse_arguments()
@@ -792,8 +904,14 @@ def simple_backup():
         euid = os.geteuid()
 
         if euid == 0:
-            user = os.getenv('SUDO_USER')
+            user = _detect_user()
+
+            if user is not None:
                 homedir = os.path.expanduser(f'~{user}')
+            else:
+                logger.warning(
+                    'Failed to detect user. You can use -u/--user parameter to manually specify it')
+                homedir = None
         else:
             user = os.getenv('USER')
             homedir = os.getenv('HOME')
@@ -807,10 +925,19 @@ def simple_backup():
         except NameError:
             pass
 
+    config_file = args.config
+
+    # Expand '~' to the home of the user running the backup, not root's
+    if config_file.startswith('~/') and user is not None:
+        config_file = f'~{user}{config_file[1:]}'
+
+    config_file = os.path.expanduser(config_file)
+
     try:
-        config_args = _read_config(args.config, user)
+        config_args = _read_config(config_file, user)
-    except (configparser.NoSectionError, configparser.NoOptionError):
+    except (configparser.Error, ValueError) as e:
-        logger.critical('Bad configuration file')
+        # configparser.Error: missing sections/options or bad syntax, ValueError: invalid values (e.g. keep=abc)
+        logger.critical('Bad configuration file: %s', e)
 
         return 6
 
@@ -823,11 +950,12 @@ def simple_backup():
     ssh_keyfile = args.keyfile if args.keyfile is not None else config_args['ssh_keyfile']
     remote_sudo = args.remote_sudo or config_args['remote_sudo']
 
-    if args.rsync_options is None:
+    # Options needed in any case (--mkpath creates the backup directory on the first run)
-        rsync_options = ['-a', '-r', '-v', '-h', '-H', '-X', '-s', '--ignore-missing-args', '--mkpath']
+    rsync_options = ['-r', '-v', '--ignore-missing-args', '--mkpath']
-    else:
-        rsync_options = ['-r', '-v']
 
+    if args.rsync_options is None:
+        rsync_options.extend(['-a', '-h', '-H', '-X', '-s'])
+    else:
         for ro in args.rsync_options:
             rsync_options.append(f'-{ro}')