New upstream version 0.9.0upstream/0.9.0

1 files changed, 1408 insertions, 0 deletions

diff --git a/raphodo/storage.py b/raphodo/storage.py
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+++ b/raphodo/storage.py
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+# Copyright (C) 2015-2017 Damon Lynch <damonlynch@gmail.com>
+# Copyright (C) 2008-2015 Canonical Ltd.
+# Copyright (C) 2013 Bernard Baeyens
+
+# This file is part of Rapid Photo Downloader.
+#
+# Rapid Photo Downloader is free software: you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Rapid Photo Downloader is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Rapid Photo Downloader.  If not,
+# see <http://www.gnu.org/licenses/>.
+
+"""
+The primary task of this module is to handle addition and removal of
+(1) cameras and (2) devices with file systems.
+
+There are two scenarios:
+
+1) User is running under a Gnome-like environment in which GVFS will
+automatically mount cameras and devices. We can monitor mounts and
+send a signal when something is mounted. The camera must be
+unmounted before libgphoto2 can access it, so we must handle that too.
+
+2) User is running under a non Gnome-like environment (e.g. KDE) in
+which GVFS may or may not be running. However we can assume GVFS will
+not automatically mount cameras and devices. In this case, using GIO
+to monitor mounts is useless, as the mounts may not occur. So we must
+monitor when cameras and other devices are added or removed ourselves.
+To do this, use udev for cameras, and udisks2 for devices with file
+systems. When a device with a file system is inserted, if it is not
+already mounted, attempt to mount it.
+
+The secondary task of this module is to provide miscellaneous services
+regarding mount points and XDG related functionality.
+"""
+
+__author__ = 'Damon Lynch'
+__copyright__ = "Copyright 2011-2017, Damon Lynch. Copyright 2008-2015 Canonical Ltd. Copyright" \
+                " 2013 Bernard Baeyens."
+
+import logging
+import os
+import re
+import sys
+import time
+import subprocess
+import shlex
+import pwd
+from collections import namedtuple
+from typing import Optional, Tuple, List, Dict, Any
+from urllib.request import pathname2url
+from tempfile import NamedTemporaryFile
+
+from PyQt5.QtCore import (QStorageInfo, QObject, pyqtSignal, QFileSystemWatcher, pyqtSlot)
+from xdg.DesktopEntry import DesktopEntry
+from xdg import BaseDirectory
+import xdg
+
+import gi
+
+gi.require_version('GUdev', '1.0')
+gi.require_version('UDisks', '2.0')
+gi.require_version('GExiv2', '0.10')
+gi.require_version('GLib', '2.0')
+from gi.repository import GUdev, UDisks, GLib
+
+from gettext import gettext as _
+
+from raphodo.constants import Desktop, Distro
+from raphodo.utilities import (
+    process_running, log_os_release, remove_topmost_directory_from_path, find_mount_point
+)
+
+logging_level = logging.DEBUG
+
+try:
+    from gi.repository import Gio
+
+    have_gio = True
+except ImportError:
+    have_gio = False
+
+StorageSpace = namedtuple('StorageSpace', 'bytes_free, bytes_total, path')
+CameraDetails = namedtuple('CameraDetails', 'model, port, display_name, is_mtp, storage_desc')
+UdevAttr = namedtuple('UdevAttr', 'is_mtp_device, vendor, model')
+
+PROGRAM_DIRECTORY = 'rapid-photo-downloader'
+
+
+def get_distro_id(id_or_id_like: str) -> Distro:
+    try:
+        return Distro[id_or_id_like.strip()]
+    except KeyError:
+        return Distro.unknown
+
+
+def get_distro() -> Distro:
+    if os.path.isfile('/etc/os-release'):
+        with open('/etc/os-release', 'r') as f:
+            for line in f:
+                if line.startswith('ID='):
+                    return get_distro_id(line[3:])
+                if line.startswith('ID_LIKE='):
+                    return get_distro_id(line[8:])
+    return Distro.unknown
+
+
+def get_user_name() -> str:
+    """
+    Gets the user name of the process owner, with no exception checking
+    :return: user name of the process owner
+    """
+
+    return pwd.getpwuid(os.getuid())[0]
+
+
+def get_path_display_name(path: str) -> Tuple[str, str]:
+    """
+    Return a name for the path (path basename),
+    removing a final '/' when it's not the root of the
+    file system.
+
+    :param path: path to generate the display name for
+    :return: display name and sanitized path
+    """
+    if path.endswith(os.sep) and path != os.sep:
+        path = path[:-1]
+
+    if path == os.sep:
+        display_name = _('File system root')
+    else:
+        display_name = os.path.basename(path)
+    return display_name, path
+
+
+def get_media_dir() -> str:
+    """
+    Returns the media directory, i.e. where external mounts are mounted.
+
+    Assumes mount point of /media/<USER>.
+
+    """
+
+    if sys.platform.startswith('linux'):
+        media_dir = '/media/{}'.format(get_user_name())
+        run_media_dir = '/run{}'.format(media_dir)
+        distro = get_distro()
+        if os.path.isdir(run_media_dir) and distro not in (
+                Distro.ubuntu, Distro.debian, Distro.neon, Distro.galliumos):
+            if distro not in (Distro.fedora, Distro.manjaro, Distro.arch, Distro.opensuse,
+                              Distro.gentoo):
+                logging.debug("Detected /run/media directory, but distro does not appear to "
+                              "be Fedora, Arch, openSUSE, Gentoo or Manjaro")
+                log_os_release()
+            return run_media_dir
+        return media_dir
+    else:
+        raise ("Mounts.setValidMountPoints() not implemented on %s", sys.platform())
+
+
+class ValidMounts():
+    r"""
+    Operations to find 'valid' mount points, i.e. the places in which
+    it's sensible for a user to mount a partition. Valid mount points:
+    include /home/<USER> , /media/<USER>, and /run/media/<USER>
+    include directories in /etc/fstab, except /, /home, and swap
+    However if only considering external mounts, the the mount must be
+    under /media/<USER> or /run/media/<user>
+    """
+
+    def __init__(self, onlyExternalMounts: bool):
+        """
+        :param onlyExternalMounts: if True, valid mounts must be under
+        /media/<USER> or /run/media/<user>
+        """
+        self.validMountFolders = None  # type: Tuple[str]
+        self.onlyExternalMounts = onlyExternalMounts
+        self._setValidMountFolders()
+        assert '/' not in self.validMountFolders
+        if logging_level == logging.DEBUG:
+            self.logValidMountFolders()
+
+    def isValidMountPoint(self, mount: QStorageInfo) -> bool:
+        """
+        Determine if the path of the mount point starts with a valid
+        path
+        :param mount: QStorageInfo to be tested
+        :return:True if mount is a mount under a valid mount, else False
+        """
+        for m in self.validMountFolders:
+            if mount.rootPath().startswith(m):
+                return True
+        return False
+
+    def pathIsValidMountPoint(self, path: str) -> bool:
+        """
+        Determine if path indicates a mount point under a valid mount
+        point
+        :param path: path to be tested
+        :return:True if path is a mount under a valid mount, else False
+        """
+        for m in self.validMountFolders:
+            if path.startswith(m):
+                return True
+        return False
+
+    def mountedValidMountPointPaths(self) -> Tuple[str]:
+        """
+        Return paths of all the currently mounted partitions that are
+        valid
+        :return: tuple of currently mounted valid partition paths
+        """
+
+        return tuple(filter(self.pathIsValidMountPoint, mountPaths()))
+
+    def mountedValidMountPoints(self) -> Tuple[QStorageInfo]:
+        """
+        Return mount points of all the currently mounted partitions
+        that are valid
+        :return: tuple of currently mounted valid partition
+        """
+
+        return tuple(filter(self.isValidMountPoint, QStorageInfo.mountedVolumes()))
+
+    def _setValidMountFolders(self) -> None:
+        """
+        Determine the valid mount point folders and set them in
+        self.validMountFolders, e.g. /media/<USER>, etc.
+        """
+
+        if not sys.platform.startswith('linux'):
+            raise ("Mounts.setValidMountPoints() not implemented on %s", sys.platform())
+        else:
+            try:
+                media_dir = get_media_dir()
+            except:
+                logging.critical("Unable to determine username of this process")
+                media_dir = ''
+            logging.debug("Media dir is %s", media_dir)
+            if self.onlyExternalMounts:
+                self.validMountFolders = (media_dir, )
+            else:
+                home_dir = os.path.expanduser('~')
+                validPoints = [home_dir, media_dir]
+                for point in self.mountPointInFstab():
+                    validPoints.append(point)
+                self.validMountFolders = tuple(validPoints)
+
+    def mountPointInFstab(self):
+        """
+        Yields a list of mount points in /etc/fstab
+        The mount points will exclude /, /home, and swap
+        """
+
+        with open('/etc/fstab') as f:
+            l = []
+            for line in f:
+                # As per fstab specs: white space is either Tab or space
+                # Ignore comments, blank lines
+                # Also ignore swap file (mount point none), root, and /home
+                m = re.match(r'^(?![\t ]*#)\S+\s+(?!(none|/[\t ]|/home))('
+                             r'?P<point>\S+)',
+                             line)
+                if m is not None:
+                    yield (m.group('point'))
+
+    def logValidMountFolders(self):
+        """
+        Output nicely formatted debug logging message
+        """
+
+        assert len(self.validMountFolders) > 0
+        if logging_level == logging.DEBUG:
+            msg = "To be recognized, partitions must be mounted under "
+            if len(self.validMountFolders) > 2:
+                msg += "one of "
+                for p in self.validMountFolders[:-2]:
+                    msg += "{}, ".format(p)
+                msg += "{} or {}".format(self.validMountFolders[-2],
+                                         self.validMountFolders[-1])
+            elif len(self.validMountFolders) == 2:
+                msg += "{} or {}".format(self.validMountFolders[0],
+                                         self.validMountFolders[1])
+            else:
+                msg += self.validMountFolders[0]
+            logging.debug(msg)
+
+
+def mountPaths():
+    """
+    Yield all the mount paths returned by QStorageInfo
+    """
+
+    for m in QStorageInfo.mountedVolumes():
+        yield m.rootPath()
+
+
+def has_non_empty_dcim_folder(path: str) -> bool:
+    """
+    Checks to see if below the path there is a DCIM folder,
+    if the folder is readable, and if it has any contents
+    :param path: path to check
+    :return: True if has valid DCIM, False otherwise
+    """
+
+    try:
+        has_dcim = "DCIM" in os.listdir(path)
+    except (PermissionError, FileNotFoundError, OSError):
+        return False
+    except:
+        logging.error("Unknown error occurred while probing potential source folder %s", path)
+        return False
+    if has_dcim:
+        dcim_folder = os.path.join(path, 'DCIM')
+        if os.path.isdir(dcim_folder) and os.access(dcim_folder, os.R_OK):
+            return len(os.listdir(dcim_folder)) > 0
+    return False
+
+
+def get_desktop_environment() -> Optional[str]:
+    """
+    Determine desktop environment using environment variable XDG_CURRENT_DESKTOP
+
+    :return: str with XDG_CURRENT_DESKTOP value
+    """
+
+    return os.getenv('XDG_CURRENT_DESKTOP')
+
+
+def get_desktop() -> Desktop:
+    """
+    Determine desktop environment
+    :return: enum representing desktop environment,
+    Desktop.unknown if unknown.
+    """
+
+    try:
+        env = get_desktop_environment().lower()
+    except AttributeError:
+        # Occurs when there is no value set
+        return Desktop.unknown
+
+    if env == 'unity:unity7':
+        env = 'unity'
+    elif env == 'x-cinnamon':
+        env = 'cinnamon'
+    try:
+        return Desktop[env]
+    except KeyError:
+        return Desktop.unknown
+
+
+def gvfs_controls_mounts() -> bool:
+    """
+    Determine if GVFS controls mounts on this system.
+
+    By default, common desktop environments known to use it are assumed
+    to be using it or not. If not found in this list, then the list of
+    running processes is searched, looking for a match against 'gvfs-gphoto2',
+    which will match what is at the time of this code being developed called
+    'gvfs-gphoto2-volume-monitor', which is what we're most interested in.
+
+    :return: True if so, False otherwise
+    """
+
+    desktop = get_desktop()
+    if desktop in (Desktop.gnome, Desktop.unity, Desktop.cinnamon, Desktop.xfce,
+                   Desktop.mate, Desktop.lxde):
+        return True
+    elif desktop == Desktop.kde:
+        return False
+    return process_running('gvfs-gphoto2')
+
+
+def _get_xdg_special_dir(dir_type: gi.repository.GLib.UserDirectory,
+                         home_on_failure: bool=True) -> Optional[str]:
+    path = GLib.get_user_special_dir(dir_type)
+    if path is None and home_on_failure:
+        return os.path.expanduser('~')
+    return path
+
+def xdg_photos_directory(home_on_failure: bool=True) -> Optional[str]:
+    """
+    Get localized version of /home/<USER>/Pictures
+
+    :param home_on_failure: if the directory does not exist, return
+     the home directory instead
+    :return: the directory if it is specified, else the user's
+    home directory or None
+    """
+    return _get_xdg_special_dir(GLib.USER_DIRECTORY_PICTURES, home_on_failure)
+
+
+def xdg_videos_directory(home_on_failure: bool=True) -> str:
+    """
+    Get localized version of /home/<USER>/Videos
+
+    :param home_on_failure: if the directory does not exist, return
+     the home directory instead
+    :return: the directory if it is specified, else the user's
+    home directory or None
+    """
+    return _get_xdg_special_dir(GLib.USER_DIRECTORY_VIDEOS, home_on_failure)
+
+def xdg_desktop_directory(home_on_failure: bool=True) -> str:
+    """
+    Get localized version of /home/<USER>/Desktop
+
+    :param home_on_failure: if the directory does not exist, return
+     the home directory instead
+    :return: the directory if it is specified, else the user's
+    home directory or None
+    """
+    return _get_xdg_special_dir(GLib.UserDirectory.DIRECTORY_DESKTOP, home_on_failure)
+
+def xdg_photos_identifier() -> str:
+    """
+    Get special subfoler indicated by the localized version of /home/<USER>/Pictures
+    :return: the subfolder name if it is specified, else the localized version of 'Pictures'
+    """
+
+    path = _get_xdg_special_dir(GLib.USER_DIRECTORY_PICTURES, home_on_failure=False)
+    if path is None:
+        # translators: the name of the Pictures folder
+        return _('Pictures')
+    return os.path.basename(path)
+
+def xdg_videos_identifier() -> str:
+    """
+    Get special subfoler indicated by the localized version of /home/<USER>/Pictures
+    :return: the subfolder name if it is specified, else the localized version of 'Pictures'
+    """
+
+    path = _get_xdg_special_dir(GLib.USER_DIRECTORY_VIDEOS, home_on_failure=False)
+    if path is None:
+        # translators: the name of the Videos folder
+        return _('Videos')
+    return os.path.basename(path)
+
+
+def make_program_directory(path: str) -> str:
+    """
+    Creates a subfolder used by Rapid Photo Downloader.
+
+    Does not catch errors.
+
+    :param path: location where the subfolder should be
+    :return: the full path of the new directory
+    """
+    program_dir = os.path.join(path, 'rapid-photo-downloader')
+    if not os.path.exists(program_dir):
+        os.mkdir(program_dir)
+    elif not os.path.isdir(program_dir):
+        os.remove(program_dir)
+        os.mkdir(program_dir)
+    return program_dir
+
+
+def get_program_cache_directory(create_if_not_exist: bool = False) -> Optional[str]:
+    """
+    Get Rapid Photo Downloader cache directory.
+
+    Is assumed to be under $XDG_CACHE_HOME or if that doesn't exist,
+     ~/.cache.
+    :param create_if_not_exist: creates directory if it does not exist.
+    :return: the full path of the cache directory, or None on error
+    """
+    try:
+        cache_directory = BaseDirectory.xdg_cache_home
+        if not create_if_not_exist:
+            return os.path.join(cache_directory, PROGRAM_DIRECTORY)
+        else:
+            return make_program_directory(cache_directory)
+    except OSError:
+        logging.error("An error occurred while creating the cache directory")
+        return None
+
+
+def get_program_logging_directory(create_if_not_exist: bool = False) -> Optional[str]:
+    """
+    Get directory in which to store program log files.
+
+    Log files are kept in the cache dirctory.
+
+    :param create_if_not_exist:
+    :return: the full path of the logging directory, or None on error
+    """
+    cache_directory = get_program_cache_directory(create_if_not_exist=create_if_not_exist)
+    log_dir = os.path.join(cache_directory, 'log')
+    if os.path.isdir(log_dir):
+        return log_dir
+    if create_if_not_exist:
+        try:
+            if os.path.isfile(log_dir):
+                os.remove(log_dir)
+            os.mkdir(log_dir, 0o700)
+            return log_dir
+        except OSError:
+            logging.error("An error occurred while creating the log directory")
+    return None
+
+
+def get_program_data_directory(create_if_not_exist=False) -> Optional[str]:
+    """
+    Get Rapid Photo Downloader data directory, which is assumed to be
+    under $XDG_DATA_HOME or if that doesn't exist,  ~/.local/share
+    :param create_if_not_exist: creates directory if it does not exist.
+    :return: the full path of the data directory, or None on error
+    """
+    try:
+        data_directory = BaseDirectory.xdg_data_dirs[0]
+        if not create_if_not_exist:
+            return os.path.join(data_directory, PROGRAM_DIRECTORY)
+        else:
+            return make_program_directory(data_directory)
+    except OSError:
+        logging.error("An error occurred while creating the data directory")
+        return None
+
+
+def get_fdo_cache_thumb_base_directory() -> str:
+    """
+    Get the Freedesktop.org thumbnail directory location
+    :return: location
+    """
+
+    # LXDE is a special case: handle it
+    if get_desktop() == Desktop.lxde:
+        return os.path.join(os.path.expanduser('~'), '.thumbnails')
+
+    return os.path.join(BaseDirectory.xdg_cache_home, 'thumbnails')
+
+
+def get_default_file_manager(remove_args: bool = True) -> Optional[str]:
+    """
+    Attempt to determine the default file manager for the system
+    :param remove_args: if True, remove any arguments such as %U from
+     the returned command
+    :return: command (without path) if found, else None
+    """
+    assert sys.platform.startswith('linux')
+    cmd = shlex.split('xdg-mime query default inode/directory')
+    try:
+        desktop_file = subprocess.check_output(cmd, universal_newlines=True)
+    except:
+        return None
+    # Remove new line character from output
+    desktop_file = desktop_file[:-1]
+    if desktop_file.endswith(';'):
+        desktop_file = desktop_file[:-1]
+    for desktop_path in ('/usr/local/share/applications/', '/usr/share/applications/'):
+        path = os.path.join(desktop_path, desktop_file)
+        if os.path.exists(path):
+            try:
+                desktop_entry = DesktopEntry(path)
+            except xdg.Exceptions.ParsingError:
+                return None
+            try:
+                desktop_entry.parse(path)
+            except:
+                return None
+            fm = desktop_entry.getExec()
+            if remove_args:
+                return fm.split()[0]
+            else:
+                return fm
+
+
+def get_uri(full_file_name: Optional[str]=None,
+            path: Optional[str]=None,
+            camera_details: Optional[CameraDetails]=None,
+            desktop_environment: Optional[bool]=True) -> str:
+    """
+    Generate and return the URI for the file, which varies depending on
+    which device it is
+
+    :param full_file_name: full filename and path
+    :param path: straight path when not passing a full_file_name
+    :param camera_details: see named tuple CameraDetails for parameters
+    :param desktop_environment: if True, will to generate a URI accepted
+     by Gnome and KDE desktops, which means adjusting the URI if it appears to be an
+     MTP mount. Includes the port too.
+    :return: the URI
+    """
+
+    if camera_details is None:
+        prefix = 'file://'
+        if desktop_environment:
+            desktop = get_desktop()
+            if full_file_name and desktop in (Desktop.mate, Desktop.kde):
+                full_file_name = os.path.dirname(full_file_name)
+    else:
+        if not desktop_environment:
+            if full_file_name or path:
+                prefix = 'gphoto2://'
+            else:
+                prefix = 'gphoto2://' + pathname2url('[{}]'.format(camera_details.port))
+        else:
+            # Attempt to generate a URI accepted by desktop environments
+            if camera_details.is_mtp:
+                if full_file_name:
+                    full_file_name = remove_topmost_directory_from_path(full_file_name)
+                elif path:
+                    path = remove_topmost_directory_from_path(path)
+
+                desktop = get_desktop()
+                if gvfs_controls_mounts():
+                    prefix = 'mtp://' + pathname2url('[{}]/{}'.format(
+                        camera_details.port, camera_details.storage_desc))
+                elif desktop == Desktop.kde:
+                    prefix = 'mtp:/' + pathname2url('{}/{}'.format(
+                        camera_details.display_name, camera_details.storage_desc))
+                    # Dolphin doesn't highlight the file if it's passed.
+                    # Instead it tries to open it, but fails.
+                    # So don't pass the file, just the directory it's in.
+                    if full_file_name:
+                        full_file_name = os.path.dirname(full_file_name)
+                else:
+                    logging.error("Don't know how to generate MTP prefix for %s", desktop.name)
+            else:
+                prefix = 'gphoto2://' + pathname2url('[{}]'.format(camera_details.port))
+    if full_file_name or path:
+        uri = '{}{}'.format(prefix, pathname2url(full_file_name or path))
+    else:
+        uri = prefix
+    return uri
+
+
+ValidatedFolder = namedtuple('ValidatedFolder', 'valid, absolute_path')
+
+
+def validate_download_folder(path: Optional[str],
+                             write_on_waccesss_failure: bool=False) -> ValidatedFolder:
+    r"""
+    Check if folder exists and is writeable.
+
+    Accepts None as a folder, which will always be invalid.
+
+    :param path: path to analyze
+    :param write_on_waccesss_failure: if os.access reports path is not writable, test
+     nonetheless to see if it's writable by writing and deleting a test file 
+    :return: Tuple indicating validity and path made absolute
+
+    >>> validate_download_folder('/some/bogus/and/ridiculous/path')
+    ValidatedFolder(valid=False, absolute_path='/some/bogus/and/ridiculous/path')
+    >>> validate_download_folder(None)
+    ValidatedFolder(valid=False, absolute_path='')
+    >>> validate_download_folder('')
+    ValidatedFolder(valid=False, absolute_path='')
+    """
+
+    if not path:
+        return ValidatedFolder(False, '')
+    absolute_path = os.path.abspath(path)
+    valid = os.path.isdir(path) and os.access(path, os.W_OK)
+    if not valid and write_on_waccesss_failure and os.path.isdir(path):
+        try:
+            with NamedTemporaryFile(dir=path):
+                # the path is in fact writeable -- can happen with NFS
+                valid = True
+        except Exception:
+            logging.warning('While validating download / backup folder, failed to write a '
+                            'temporary file to %s', path)
+
+    return ValidatedFolder(valid, absolute_path)
+
+
+def validate_source_folder(path: Optional[str]) -> ValidatedFolder:
+    r"""
+    Check if folder exists and is readable.
+
+    Accepts None as a folder, which will always be invalid.
+
+    :param path: path to analyze
+    :return: Tuple indicating validity and path made absolute
+
+    >>> validate_source_folder('/some/bogus/and/ridiculous/path')
+    ValidatedFolder(valid=False, absolute_path='/some/bogus/and/ridiculous/path')
+    >>> validate_source_folder(None)
+    ValidatedFolder(valid=False, absolute_path='')
+    >>> validate_source_folder('')
+    ValidatedFolder(valid=False, absolute_path='')
+    """
+
+    if not path:
+        return ValidatedFolder(False, '')
+    absolute_path = os.path.abspath(path)
+    valid = os.path.isdir(path) and os.access(path, os.R_OK)
+    return ValidatedFolder(valid, absolute_path)
+
+
+def udev_attributes(devname: str) -> Optional[UdevAttr]:
+    """
+    Query udev to see if device is an MTP device.
+
+    :param devname: udev DEVNAME e.g. '/dev/bus/usb/001/003'
+    :return True if udev property ID_MTP_DEVICE == '1', else False
+    """
+
+    client = GUdev.Client(subsystems=['usb', 'block'])
+    enumerator = GUdev.Enumerator.new(client)
+    enumerator.add_match_property('DEVNAME', devname)
+    for device in enumerator.execute():
+        model = device.get_property('ID_MODEL')  # type: str
+        if model is not None:
+            is_mtp = device.get_property('ID_MTP_DEVICE') == '1'
+            vendor = device.get_property('ID_VENDOR')  # type: str
+            model = model.replace('_', ' ').strip()
+            vendor = vendor.replace('_', ' ').strip()
+            return UdevAttr(is_mtp, vendor, model)
+    return None
+
+
+def fs_device_details(path: str) -> Tuple:
+    """
+    :return: device (volume) name, uri, root path and filesystem type
+     of the mount the path is on
+    """
+    qsInfo = QStorageInfo(path)
+    name = qsInfo.displayName()
+    root_path = qsInfo.rootPath()
+    uri = 'file://{}'.format(pathname2url(root_path))
+    fstype = qsInfo.fileSystemType()
+    if isinstance(fstype, bytes):
+        fstype = fstype.decode()
+    return name, uri, root_path, fstype
+
+
+class WatchDownloadDirs(QFileSystemWatcher):
+    """
+    Create a file system watch to monitor if there are changes to the
+    download directories
+    """
+
+    def updateWatchPathsFromPrefs(self, prefs) -> None:
+        """
+        Update the watched directories using values from the program preferences
+        :param prefs: program preferences
+        :type prefs: raphodo.preferences.Preferences
+        """
+
+        logging.debug("Updating watched paths")
+
+        paths = (os.path.dirname(path) for path in (prefs.photo_download_folder,
+                                                    prefs.video_download_folder))
+        watch = {path for path in paths if path}
+
+        existing_watches = set(self.directories())
+
+        if watch == existing_watches:
+            return
+
+        new = watch - existing_watches
+        if new:
+            new = list(new)
+            logging.debug("Adding to watched paths: %s", ', '.join(new))
+            failures = self.addPaths(new)
+            if failures:
+                logging.debug("Failed to add watched paths: %s", failures)
+
+        old = existing_watches - watch
+        if old:
+            old = list(old)
+            logging.debug("Removing from watched paths: %s", ', '.join(old))
+            failures = self.removePaths(old)
+            if failures:
+                logging.debug("Failed to remove watched paths: %s", failures)
+
+    def closeWatch(self) -> None:
+        """
+        End all watches.
+        """
+        dirs = self.directories()
+        if dirs:
+            self.removePaths(dirs)
+
+
+class CameraHotplug(QObject):
+    cameraAdded = pyqtSignal()
+    cameraRemoved = pyqtSignal()
+
+    def __init__(self):
+        super().__init__()
+        self.cameras = {}
+
+    @pyqtSlot()
+    def startMonitor(self):
+        self.client = GUdev.Client(subsystems=['usb', 'block'])
+        self.client.connect('uevent', self.ueventCallback)
+        logging.debug("... camera hotplug monitor started")
+        self.enumerateCameras()
+        if self.cameras:
+            logging.debug("Camera Hotplug found %d cameras:", len(self.cameras))
+            for port, model in self.cameras.items():
+                logging.debug("%s at %s", model, port)
+
+    def enumerateCameras(self):
+        """
+        Query udev to get the list of cameras store their path and
+        model in our internal dict, which is useful when responding to
+        camera removal.
+        """
+        enumerator = GUdev.Enumerator.new(self.client)
+        enumerator.add_match_property('ID_GPHOTO2', '1')
+        for device in enumerator.execute():
+            model = device.get_property('ID_MODEL')
+            if model is not None:
+                path = device.get_sysfs_path()
+                self.cameras[path] = model
+
+    def ueventCallback(self, client: GUdev.Client, action: str, device: GUdev.Device) -> None:
+
+        # for key in device.get_property_keys():
+        #     print(key, device.get_property(key))
+        if device.get_property('ID_GPHOTO2') == '1':
+            self.camera(action, device)
+
+    def camera(self, action: str, device: GUdev.Device) -> None:
+        # For some reason, the add and remove camera event is triggered twice.
+        # The second time the device information is a variation on information
+        # from the first time.
+        path = device.get_sysfs_path()
+        parent_device = device.get_parent()
+        parent_path = parent_device.get_sysfs_path()
+        logging.debug("Device change: %s. Path: %s Parent Device: %s Parent path: %s",
+                      action, path, parent_device, parent_path)
+
+        if action == 'add':
+            if parent_path not in self.cameras:
+                model = device.get_property('ID_MODEL')
+                logging.debug("Hotplug: new camera: %s", model)
+                self.cameras[path] = model
+                self.cameraAdded.emit()
+            else:
+                logging.debug("Hotplug: already know about %s", self.cameras[
+                    parent_path])
+
+        elif action == 'remove':
+            emit_remove = False
+            name = ''
+            if path in self.cameras:
+                name = self.cameras[path]
+                del self.cameras[path]
+                emit_remove = True
+            elif device.get_property('ID_GPHOTO2') == '1':
+                # This should not need to be called. However,
+                # self.enumerateCameras may not have been called earlier
+                name = device.get_property('ID_MODEL')
+                if name is not None:
+                    emit_remove = True
+            if emit_remove:
+                logging.debug("Hotplug: %s has been removed", name)
+                self.cameraRemoved.emit()
+
+
+class UDisks2Monitor(QObject):
+    # Most of this class is Copyright 2008-2015 Canonical
+
+    partitionMounted = pyqtSignal(str, list, bool)
+    partitionUnmounted = pyqtSignal(str)
+
+    loop_prefix = '/org/freedesktop/UDisks2/block_devices/loop'
+    not_interesting = (
+        '/org/freedesktop/UDisks2/block_devices/dm_',
+        '/org/freedesktop/UDisks2/block_devices/ram',
+        '/org/freedesktop/UDisks2/block_devices/zram',
+    )
+
+    def __init__(self, validMounts: ValidMounts) -> None:
+        super().__init__()
+        self.validMounts = validMounts
+
+    @pyqtSlot()
+    def startMonitor(self) -> None:
+        self.udisks = UDisks.Client.new_sync(None)
+        self.manager = self.udisks.get_object_manager()
+        self.manager.connect('object-added',
+                             lambda man, obj: self._udisks_obj_added(obj))
+        self.manager.connect('object-removed',
+                             lambda man, obj: self._device_removed(obj))
+
+        # Track the paths of the mount points, which is useful when unmounting
+        # objects.
+        self.known_mounts = {}  # type: Dict[str, str]
+        for obj in self.manager.get_objects():
+            path = obj.get_object_path()
+            fs = obj.get_filesystem()
+            if fs:
+                mount_points = fs.get_cached_property('MountPoints').get_bytestring_array()
+                if mount_points:
+                    self.known_mounts[path] = mount_points[0]
+        logging.debug("... UDisks2 monitor started")
+
+    def _udisks_obj_added(self, obj) -> None:
+        path = obj.get_object_path()
+        for boring in self.not_interesting:
+            if path.startswith(boring):
+                return
+        block = obj.get_block()
+        if not block:
+            return
+
+        drive = self._get_drive(block)
+
+        part = obj.get_partition()
+        is_system = block.get_cached_property('HintSystem').get_boolean()
+        is_loop = path.startswith(self.loop_prefix) and not \
+            block.get_cached_property('ReadOnly').get_boolean()
+        if not is_system or is_loop:
+            if part:
+                self._udisks_partition_added(obj, block, drive, path)
+
+    def _get_drive(self, block) -> Optional[UDisks.Drive]:
+        drive_name = block.get_cached_property('Drive').get_string()
+        if drive_name != '/':
+            return self.udisks.get_object(drive_name).get_drive()
+        else:
+            return None
+
+    def _udisks_partition_added(self, obj, block, drive, path) -> None:
+        logging.debug('UDisks: partition added: %s' % path)
+        fstype = block.get_cached_property('IdType').get_string()
+        logging.debug('Udisks: id-type: %s' % fstype)
+
+        fs = obj.get_filesystem()
+
+        if fs:
+            icon_names = self.get_icon_names(obj)
+
+            if drive is not None:
+                ejectable = drive.get_property('ejectable')
+            else:
+                ejectable = False
+            mount_point = ''
+            mount_points = fs.get_cached_property('MountPoints').get_bytestring_array()
+            if len(mount_points) == 0:
+                try:
+                    logging.debug("UDisks: attempting to mount %s", path)
+                    mount_point = self.retry_mount(fs, fstype)
+                    if not mount_point:
+                        raise
+                    else:
+                        logging.debug("UDisks: successfully mounted at %s", mount_point)
+                except:
+                    logging.error('UDisks: could not mount the device: %s', path)
+                    return
+            else:
+                mount_point = mount_points[0]
+                logging.debug("UDisks: already mounted at %s", mount_point)
+
+            self.known_mounts[path] = mount_point
+            if self.validMounts.pathIsValidMountPoint(mount_point):
+                self.partitionMounted.emit(mount_point, icon_names, ejectable)
+
+        else:
+            logging.debug("Udisks: partition has no file system %s", path)
+
+    def retry_mount(self, fs, fstype) -> str:
+        # Variant parameter construction Copyright Bernard Baeyens, and is
+        # licensed under GNU General Public License Version 2 or higher.
+        # https://github.com/berbae/udisksvm
+        list_options = ''
+        if fstype == 'vfat':
+            list_options = 'flush'
+        elif fstype == 'ext2':
+            list_options = 'sync'
+        G_VARIANT_TYPE_VARDICT = GLib.VariantType.new('a{sv}')
+        param_builder = GLib.VariantBuilder.new(G_VARIANT_TYPE_VARDICT)
+        optname = GLib.Variant.new_string('fstype')  # s
+        value = GLib.Variant.new_string(fstype)
+        vvalue = GLib.Variant.new_variant(value)  # v
+        newsv = GLib.Variant.new_dict_entry(optname, vvalue)  # {sv}
+        param_builder.add_value(newsv)
+        optname = GLib.Variant.new_string('options')
+        value = GLib.Variant.new_string(list_options)
+        vvalue = GLib.Variant.new_variant(value)
+        newsv = GLib.Variant.new_dict_entry(optname, vvalue)
+        param_builder.add_value(newsv)
+        vparam = param_builder.end()  # a{sv}
+
+        # Try to mount until it does not fail with "Busy"
+        timeout = 10
+        while timeout >= 0:
+            try:
+                return fs.call_mount_sync(vparam, None)
+            except GLib.GError as e:
+                if not 'UDisks2.Error.DeviceBusy' in e.message:
+                    raise
+                logging.debug('Udisks: Device busy.')
+                time.sleep(0.3)
+                timeout -= 1
+        return ''
+
+    def get_icon_names(self, obj: UDisks.Object) -> List[str]:
+        # Get icon information, if possible
+        icon_names = []
+        if have_gio:
+            info = self.udisks.get_object_info(obj)
+            icon = info.get_icon()
+            if isinstance(icon, Gio.ThemedIcon):
+                icon_names = icon.get_names()
+        return icon_names
+
+    # Next four class member functions from Damon Lynch, not Canonical
+    def _device_removed(self, obj: UDisks.Object) -> None:
+        # path here refers to the udev / udisks path, not the mount point
+        path = obj.get_object_path()
+        if path in self.known_mounts:
+            mount_point = self.known_mounts[path]
+            del self.known_mounts[path]
+            self.partitionUnmounted.emit(mount_point)
+
+    def get_can_eject(self, obj: UDisks.Object) -> bool:
+        block = obj.get_block()
+        drive = self._get_drive(block)
+        if drive is not None:
+            return drive.get_property('ejectable')
+        return False
+
+    def get_device_props(self, device_path: str) -> Tuple[List[str], bool]:
+        """
+        Given a device, get the icon names suggested by udev, and
+        determine whether the mount is ejectable or not.
+        :param device_path: system path of the device to check,
+        e.g. /dev/sdc1
+        :return: icon names and eject boolean
+        """
+
+        object_path = '/org/freedesktop/UDisks2/block_devices/{}'.format(
+            os.path.split(device_path)[1])
+        obj = self.udisks.get_object(object_path)
+        icon_names = self.get_icon_names(obj)
+        can_eject = self.get_can_eject(obj)
+        return (icon_names, can_eject)
+
+    @pyqtSlot(str)
+    def unmount_volume(self, mount_point: str) -> None:
+
+        G_VARIANT_TYPE_VARDICT = GLib.VariantType.new('a{sv}')
+        param_builder = GLib.VariantBuilder.new(G_VARIANT_TYPE_VARDICT)
+
+        # Variant parameter construction Copyright Bernard Baeyens, and is
+        # licensed under GNU General Public License Version 2 or higher.
+        # https://github.com/berbae/udisksvm
+
+        optname = GLib.Variant.new_string('force')
+        value = GLib.Variant.new_boolean(False)
+        vvalue = GLib.Variant.new_variant(value)
+        newsv = GLib.Variant.new_dict_entry(optname, vvalue)
+        param_builder.add_value(newsv)
+
+        vparam = param_builder.end()                            # a{sv}
+
+        path = None
+        # Get the path from the dict we keep of known mounts
+        for key, value in self.known_mounts.items():
+            if value == mount_point:
+                path = key
+                break
+        if path is None:
+            logging.error("Could not find UDisks2 path used to be able to unmount %s", mount_point)
+
+        fs = None
+        for obj in self.manager.get_objects():
+            opath = obj.get_object_path()
+            if path == opath:
+                fs = obj.get_filesystem()
+        if fs is None:
+            logging.error("Could not find UDisks2 filesystem used to be able to unmount %s",
+                          mount_point)
+
+        logging.debug("Unmounting %s...", mount_point)
+        try:
+            fs.call_unmount(vparam, None, self.umount_volume_callback, (mount_point, fs))
+        except GLib.GError:
+            value = sys.exc_info()[1]
+            logging.error('Unmounting failed with error:')
+            logging.error("%s", value)
+
+    def umount_volume_callback(self, source_object:  UDisks.FilesystemProxy,
+                               result: Gio.AsyncResult,
+                               user_data: Tuple[str, UDisks.Filesystem]) -> None:
+        """
+        Callback for asynchronous unmount operation.
+
+        :param source_object: the FilesystemProxy object
+        :param result: result of the unmount
+        :param user_data: mount_point and the file system
+        """
+
+        mount_point, fs = user_data
+
+        try:
+            if fs.call_unmount_finish(result):
+                logging.debug("...successfully unmounted %s", mount_point)
+            else:
+                # this is the result even when the unmount was unsuccessful
+                logging.debug("...possibly failed to unmount %s", mount_point)
+        except GLib.GError as e:
+            logging.error('Exception occurred unmounting %s', mount_point)
+            logging.exception('Traceback:')
+        except:
+            logging.error('Exception occurred unmounting %s', mount_point)
+            logging.exception('Traceback:')
+
+        self.partitionUnmounted.emit(mount_point)
+
+
+if have_gio:
+    class GVolumeMonitor(QObject):
+        r"""
+        Monitor the mounting or unmounting of cameras or partitions
+        using Gnome's GIO/GVFS. Unmount cameras automatically mounted
+        by GVFS.
+
+        Raises a signal if a volume has been inserted, but will not be
+        automatically mounted. This is important because this class
+        is monitoring mounts, and if the volume is not mounted, it will
+        go unnoticed.
+        """
+
+        cameraUnmounted = pyqtSignal(bool, str, str, bool, bool)
+        cameraMounted = pyqtSignal()
+        partitionMounted = pyqtSignal(str, list, bool)
+        partitionUnmounted = pyqtSignal(str)
+        volumeAddedNoAutomount = pyqtSignal()
+        cameraPossiblyRemoved = pyqtSignal()
+
+        def __init__(self, validMounts: ValidMounts) -> None:
+            super().__init__()
+            self.vm = Gio.VolumeMonitor.get()
+            self.vm.connect('mount-added', self.mountAdded)
+            self.vm.connect('volume-added', self.volumeAdded)
+            self.vm.connect('mount-removed', self.mountRemoved)
+            self.vm.connect('volume-removed', self.volumeRemoved)
+            self.portSearch = re.compile(r'usb:([\d]+),([\d]+)')
+            self.scsiPortSearch = re.compile(r'usbscsi:(.+)')
+            self.validMounts = validMounts
+
+        def ptpCameraMountPoint(self, model: str, port: str) -> Optional[Gio.Mount]:
+            """
+            :return: the mount point of the PTP / MTP camera, if it is mounted,
+             else None. If camera is not mounted with PTP / MTP, None is
+             returned.
+            """
+
+            p = self.portSearch.match(port)
+            if p is not None:
+                p1 = p.group(1)
+                p2 = p.group(2)
+                pattern = re.compile(r'%\S\Susb%\S\S{}%\S\S{}%\S\S'.format(p1, p2))
+            else:
+                p = self.scsiPortSearch.match(port)
+                if p is None:
+                    logging.error("Unknown camera mount method %s %s", model, port)
+                return None
+
+            to_unmount = None
+
+            for mount in self.vm.get_mounts():
+                folder_extract = self.mountIsCamera(mount)
+                if folder_extract is not None:
+                    if pattern.match(folder_extract):
+                        to_unmount = mount
+                        break
+            return to_unmount
+
+        def unmountCamera(self, model: str,
+                          port: str,
+                          download_starting: bool=False,
+                          on_startup: bool=False,
+                          mount_point: Optional[Gio.Mount]=None) -> bool:
+            """
+            Unmount camera mounted on gvfs mount point, if it is
+            mounted. If not mounted, ignore.
+            :param model: model as returned by libgphoto2
+            :param port: port as returned by libgphoto2, in format like
+             usb:001,004
+            :param download_starting: if True, the unmount is occurring
+             because a download has been initiated.
+            :param on_startup: if True, the unmount is occurring during
+             the program's startup phase
+            :param mount_point: if not None, try umounting from this
+             mount point without scanning for it first
+            :return: True if an unmount operation has been initiated,
+             else returns False.
+            """
+
+            if mount_point is None:
+                to_unmount = self.ptpCameraMountPoint(model, port)
+            else:
+                to_unmount = mount_point
+
+            if to_unmount is not None:
+                logging.debug("GIO: Attempting to unmount %s...", model)
+                to_unmount.unmount_with_operation(0, None, None, self.unmountCameraCallback,
+                                                  (model, port, download_starting, on_startup))
+                return True
+
+            return False
+
+        def unmountCameraCallback(self, mount: Gio.Mount,
+                                  result: Gio.AsyncResult,
+                                  user_data: Tuple[str, str, bool, bool]) -> None:
+            """
+            Called by the asynchronous unmount operation.
+            When complete, emits a signal indicating operation
+            success, and the camera model and port
+            :param mount: camera mount
+            :param result: result of the unmount process
+            :param user_data: model and port of the camera being
+            unmounted, in the format of libgphoto2
+            """
+
+            model, port, download_starting, on_startup = user_data
+            try:
+                if mount.unmount_with_operation_finish(result):
+                    logging.debug("...successfully unmounted {}".format(model))
+                    self.cameraUnmounted.emit(True, model, port, download_starting, on_startup)
+                else:
+                    logging.debug("...failed to unmount {}".format(model))
+                    self.cameraUnmounted.emit(False, model, port, download_starting, on_startup)
+            except GLib.GError as e:
+                logging.error('Exception occurred unmounting {}'.format(model))
+                logging.exception('Traceback:')
+                self.cameraUnmounted.emit(False, model, port, download_starting, on_startup)
+
+        def unmountVolume(self, path: str) -> None:
+            """
+            Unmounts the volume represented by the path. If no volume is found
+            representing that path, nothing happens.
+
+            :param path: path of the volume. It should not end with os.sep.
+            """
+
+            for mount in self.vm.get_mounts():
+                root = mount.get_root()
+                if root is not None:
+                    mpath = root.get_path()
+                    if path == mpath:
+                        logging.info("Attempting to unmount %s...", path)
+                        mount.unmount_with_operation(0, None, None, self.unmountVolumeCallback,
+                                                     path)
+                        break
+
+        def unmountVolumeCallback(self, mount: Gio.Mount,
+                                  result: Gio.AsyncResult,
+                                  user_data: str) -> None:
+
+            """
+            Called by the asynchronous unmount operation.
+
+            :param mount: volume mount
+            :param result: result of the unmount process
+            :param user_data: the path of the device unmounted
+            """
+            path = user_data
+
+            try:
+                if mount.unmount_with_operation_finish(result):
+                    logging.info("...successfully unmounted %s", path)
+                else:
+                    logging.info("...failed to unmount %s", path)
+            except GLib.GError as e:
+                logging.error('Exception occurred unmounting %s', path)
+                logging.exception('Traceback:')
+
+
+        def mountIsCamera(self, mount: Gio.Mount) -> Optional[str]:
+            """
+            Determine if the mount point is that of a camera
+            :param mount: the mount to examine
+            :return: None if not a camera, or the component of the
+            folder name that indicates on which port it is mounted
+            """
+            root = mount.get_root()
+            if root is None:
+                logging.warning('Unable to get mount root')
+            else:
+                path = root.get_path()
+                if path:
+                    logging.debug("GIO: Looking for camera at mount {}".format(path))
+                    folder_name = os.path.split(path)[1]
+                    for s in ('gphoto2:host=', 'mtp:host='):
+                        if folder_name.startswith(s):
+                            return folder_name[len(s):]
+                if path is not None:
+                    logging.debug("GIO: camera not found at {}".format(path))
+            return None
+
+        def mountIsPartition(self, mount: Gio.Mount) -> bool:
+            """
+            Determine if the mount point is that of a valid partition,
+            i.e. is mounted in a valid location, which is under one of
+            self.validMountDirs
+            :param mount: the mount to examine
+            :return: True if the mount is a valid partiion
+            """
+            root = mount.get_root()
+            if root is None:
+                logging.warning('Unable to get mount root')
+            else:
+                path = root.get_path()
+                if path:
+                    logging.debug("GIO: Looking for valid partition at mount {}".format(path))
+                    if self.validMounts.pathIsValidMountPoint(path):
+                        logging.debug("GIO: partition found at {}".format(path))
+                        return True
+                if path is not None:
+                    logging.debug("GIO: partition is not valid mount: {}".format(path))
+            return False
+
+        def mountAdded(self, volumeMonitor, mount: Gio.Mount) -> None:
+            if self.mountIsCamera(mount):
+                self.cameraMounted.emit()
+            elif self.mountIsPartition(mount):
+                icon_names = self.getIconNames(mount)
+                self.partitionMounted.emit(mount.get_root().get_path(),
+                                           icon_names,
+                                           mount.can_eject())
+
+        def mountRemoved(self, volumeMonitor, mount: Gio.Mount) -> None:
+            if not self.mountIsCamera(mount):
+                if self.mountIsPartition(mount):
+                    logging.debug("GIO: %s has been unmounted", mount.get_name())
+                    self.partitionUnmounted.emit(mount.get_root().get_path())
+
+        def volumeAdded(self, volumeMonitor, volume: Gio.Volume) -> None:
+            logging.debug("GIO: Volume added %s. Automount: %s",
+                          volume.get_name(),
+                          volume.should_automount())
+            if not volume.should_automount():
+                # TODO is it possible to determine the device type?
+                self.volumeAddedNoAutomount.emit()
+
+        def volumeRemoved(self, volumeMonitor, volume: Gio.Volume) -> None:
+            logging.debug("GIO: %s volume removed", volume.get_name())
+            if volume.get_activation_root() is not None:
+                logging.debug("GIO: %s might be a camera", volume.get_name())
+                self.cameraPossiblyRemoved.emit()
+
+        def getIconNames(self, mount: Gio.Mount) -> List[str]:
+            icon_names = []
+            icon = mount.get_icon()
+            if isinstance(icon, Gio.ThemedIcon):
+                icon_names = icon.get_names()
+
+            return icon_names
+
+        def getProps(self, path: str) -> Tuple[Optional[List[str]], Optional[bool]]:
+            """
+            Given a mount's path, get the icon names suggested by the
+            volume monitor, and determine whether the mount is
+            ejectable or not.
+            :param path: the path of mount to check
+            :return: icon names and eject boolean
+            """
+
+            for mount in self.vm.get_mounts():
+                root = mount.get_root()
+                if root is not None:
+                    p = root.get_path()
+                    if path == p:
+                        icon_names = self.getIconNames(mount)
+                        return (icon_names, mount.can_eject())
+            return (None, None)
+
+
+def _get_info_size_value(info: Gio.FileInfo, attr: str) -> int:
+    if info.get_attribute_data(attr).type ==  Gio.FileAttributeType.UINT64:
+        return info.get_attribute_uint64(attr)
+    else:
+        return info.get_attribute_uint32(attr)
+
+
+def get_mount_size(mount: QStorageInfo) -> Tuple[int, int]:
+    """
+    Uses GIO to get bytes total and bytes free (available) for the mount that a
+    path is in.
+    
+    :param path: path located anywhere in the mount
+    :return: bytes_total, bytes_free
+    """
+
+    bytes_free = mount.bytesAvailable()
+    bytes_total = mount.bytesTotal()
+
+    if bytes_total or not have_gio:
+        return bytes_total, bytes_free
+
+    path = mount.rootPath()
+
+    logging.debug("Using GIO to query file system attributes for %s...", path)
+    p = Gio.File.new_for_path(os.path.abspath(path))
+    info = p.query_filesystem_info(','.join((Gio.FILE_ATTRIBUTE_FILESYSTEM_SIZE,
+                                             Gio.FILE_ATTRIBUTE_FILESYSTEM_FREE)))
+    logging.debug("...query of file system attributes for %s completed", path)
+    bytes_total = _get_info_size_value(info, Gio.FILE_ATTRIBUTE_FILESYSTEM_SIZE)
+    bytes_free = _get_info_size_value(info, Gio.FILE_ATTRIBUTE_FILESYSTEM_FREE)
+    return bytes_total, bytes_free