interfaces/udev,misc: only trigger udev events on input subsystem as needed
* interfaces/udev,misc: only trigger udev events on input subsystem as needed
In at least desktop environments, running 'udevadm trigger' can cause input to
be blocked as input device events are handled. Since snapd will do this for
each install and refresh, the behavior is annoying for users (especially users
with many snaps installed when snap refresh happens in the background). Instead
of unconditionally calling 'udevadm trigger', instead call:
udevadm trigger --subsystem-nomatch=input
This will trigger events for everything except the input subsystem. Interfaces
like mir, wayland and x11 which actually need to tag input subsystem devices
now use spec.TriggerSubsystem("input") to flag that the following should also
be called:
udevadm trigger --subsystem-match=input
The joystick interface uses spec.TriggerSubsystem("input/joystick") to do a
separate trigger specific to joystick events since they do not cause keyboard
and mouse input to be blocked:
udevadm trigger --property-match=ID_INPUT_JOYSTICK=1
At this time there doesn't seem to be a way to call TriggerSubsystem() during
interface disconnect, so we temporarily unconditionally call trigger for
joysticks. Because of this limitation, TriggerSubsystem() should otherwise only
by used in UDevPermanentSlot() since that policy is permanent and the tagging
won't be removed until snap removal.
* gather up different subsystems to trigger. Thanks for the suggestion zyga
* add some comments for disconnect/joystick workaround
* update comment for udev calls
* update comment harder
* tests/lib/snaps/test-snapd-udev-input-subsystem: add excutable permission bits
Signed-off-by: Maciej Borzecki <email address hidden>
* fix spread test for event access when device cgroup is in effect
* cd to $SNAP to fix non-fatal but confusing AppArmor denials with find command
* disable security-udev-input-subsystem on Debian 9
* backend.go: don't use global for subsystemTriggers
* rename GetTriggeredSubsystems to TriggeredSubsystems. Thanks to zyga
* return a copy of udevadmSubsystemTriggers. Thanks to zyga
* use strutil.ListContains. Thanks to zyga
* use iface.commonInterface.UDevConnectedPlug(spec, plug, slot). Thanks to zyga
* address review feedback from zyga
snap: don't include newline in hook environment
Currently, both hooks and apps use the global `environment`, if
specified. However, they both use slightly different mechanisms of
interpreting the environment: hooks append a newline, apps do not. The
newline causes problems when the variable is used in the shell.
Fix this issue by creating a new function to evaluate the environment
(that doesn't append a newline), and have both apps and hooks use it.
Signed-off-by: Kyle Fazzari <email address hidden>
