The backend currently allows to access and modify files without prompting
for password if any polkit authentication agent isn't available. This seems
isn't usually problem, because polkit agents are integral parts of
graphical environments / linux distributions. The agents can't be simply
disabled without root permissions and are automatically respawned. However,
this might be a problem in some non-standard cases.

This affects only users which belong to wheel group (i.e. those who are
already allowed to use sudo). It doesn't allow privilege escalation for
users, who don't belong to that group.

Let's return permission denied error also when the subject can't be
authorized by any polkit agent to prevent this behavior.

Closes: https://gitlab.gnome.org/GNOME/gvfs/issues/355

Currently, the default value of max-conns-per-host libsoup property is
used, which causes dav backend lockups if two files are	opened.	I don't
see any	easy solution how to prevent lockups, but we can definitely
reduce the chance of them by increasing max-conns properties. Much bigger
values are used by browsers nowadays. Hope that 32 is big enough for
regular use cases and small enough to not flood a server and not block
too much file descriptors...

Closes: #6

G_FILE_ATTRIBUTE_MOUNTABLE_CAN_UNMOUNT is set to TRUE, but unmount_mountable()
is not implemented. Set the attribute always to FALSE in order to prevent
errors from g_file_unmount_mountable_with_operation().

Nautilus should seamleassly use	g_mount_unmount_with_operation() if the
attribute is set to FALSE.

Closes: #15

G_FILE_ATTRIBUTE_MOUNTABLE_CAN_UNMOUNT is set to TRUE, but unmount_mountable()
is not implemented. Set the attribute always to FALSE in order to prevent
errors from g_file_unmount_mountable_with_operation().

Nautilus should seamleassly use g_mount_unmount_with_operation() if the
attribute is set to FALSE.

#15

GAsyncReadyCallback is never called from g_drive_stop, because
source_tag is not set, but checked. This obviously causes issues
for client applications. Add missing source_tag.

Closes: #1

fstat fails with EINVAL on Windows servers if O_WRONLY is used to open
(though it works properly on SAMBA servers). O_RDWR is needed to make
it work. This causes issues when copying files over gvfsd-fuse among
others.

https://bugzilla.gnome.org/show_bug.cgi?id=795805

smbc_rmdir returns 0 for non-empty dir currently even if the dir has
not been removed. Add workaround and return G_IO_ERROR_NOT_EMPTY in
this case.

https://bugzilla.gnome.org/show_bug.cgi?id=792147

If an optical drive is hard-unplugged without ejecting a media first (or
the corresponding UDisksDrive object simply disappears from D-Bus for
example due to the udisksd termination) and an audio disk or an empty
media is inside, corresponding volumes/mounts are not properly removed.
Consequently, the number of the volumes/mounts increase when plugging
and unplugging such drive. This happens because those kinds of volumes/
mounts are handled by their drives in the monitor. Unfortunately, the
drive is removed before processing them and the mounts/volumes without
the drives are ignored consequently.

Let's do not rely on the drives and handle those volumes/mounts over
corresponding UDisksBlock objects, same as it is done for other kinds of
volumes.

https://bugzilla.gnome.org/show_bug.cgi?id=719423

Commit e147e48f added missing mutex guards for job_sources, which may
unfortunately lead to deadlock because g_vfs_channel_force_close
synchronously calls g_vfs_job_source_closed which is also guarded by
the same mutex.

The deadlock reveals another bug which was in that code. The code
iterates over job_sources list, but g_vfs_job_source_closed removes
current element of the list, which leads to invalid reads and
potentially to segfaults also.

This patch tries to fix the both mentioned issues.

https://bugzilla.gnome.org/show_bug.cgi?id=794957

Code to determine tree name from device has been recently ported from
udev to gudev by commit c2d85644. Unfortunately, the gudev code floods
logs by the following messages if device is not found (it can happen
e.g. for tmpfs):
g_udev_device_has_property: assertion 'G_UDEV_IS_DEVICE (device)' failed

Udev code silently returned if NULL device was used, however, corresponding
gudev code prints the mentioned messages. Let's prevent usage of NULL
device in order to prevent those messages.

https://bugzilla.gnome.org/show_bug.cgi?id=795191

Backend crashes in on_show_processes_reply callback if
g_vfs_backend_unmount_with_operation async call has been completed
over on_update_processes_timeout in the meantime and releases GTask
data (i.e. "Volume is busy" prompt is being shown and blocking
operations have been finished).

This patch simplify the handling. With this patch, the async call
is completed only from one place, on_show_processes_reply. If there
are no more processes, g_mount_source_abort is called from
on_update_processes_timeout only and the reply is handled by
on_show_processes_reply consequently. This prevents the crashes.

Just a note that client side ensures that on_show_processes_reply is
called only once.

https://bugzilla.gnome.org/show_bug.cgi?id=794113

Debug from send_reply is printed once from GVfsJobUnmount and once
from GVfsJobDBus, which is confusing and redundant, let's remove th
one from GVfsJobUnmount.

https://bugzilla.gnome.org/show_bug.cgi?id=794113

Use already defined gvfs_name and gvfs_version variables to print
also gvfs version in the configuration summary.

https://bugzilla.gnome.org/show_bug.cgi?id=793920

autotools does print summary of the options at the end of the
configuration step, but meson doesn't. Let's add the summary again,
but use names and order from meson_options.txt.

https://bugzilla.gnome.org/show_bug.cgi?id=793920

If there's no device file, which means libusb won't be able to open the
device, no need to print a warning, simply ignore the device.

https://bugzilla.gnome.org/show_bug.cgi?id=793925

If there's no device file, which means libusb won't be able to open the
device, no need to print a warning, simply ignore the device.

https://bugzilla.gnome.org/show_bug.cgi?id=793925

It's set, but not used anywhere.

https://bugzilla.gnome.org/show_bug.cgi?id=793923

Move the variable into the block where it's used, behind a compile-time
version check.

gvfs/daemon/gvfsbackendgoogle.c: In function ‘g_vfs_backend_google_query_fs_info’:
gvfs/daemon/gvfsbackendgoogle.c:2041:22: warning: unused variable ‘self’ [-Wunused-variable]
   GVfsBackendGoogle *self = G_VFS_BACKEND_GOOGLE (_self);
                      ^~~~

https://bugzilla.gnome.org/show_bug.cgi?id=793922