rules: make rule processing conditional on X11 being available

docs/capabilities.md

@@ -109,7 +109,8 @@ program.
 
 Solaar can process HID++ Feature Notifications from devices to, for example,
 change the speed of some thumb wheels.  For more information on this capability of Solaar see
-[the rules page](https://pwr-solaar.github.io/Solaar/rules).
+[the rules page](https://pwr-solaar.github.io/Solaar/rules).  As much of rule processing
+depends on X11, this capability is only when running under X11.
 
 Users can edit rules using a GUI by clicking on the `Edit Rule` button in the Solaar main window.
 

docs/rules.md

@@ -3,6 +3,8 @@ title: Rule Processing of HID++ Notifications
 layout: page
 ---
 
+Note that rule processing is only available when running under X11.
+
 Logitech devices that use HID++ version 2.0 or greater produce feature-based
 notifications that Solaar can process using a simple rule language.  For
 example, using rules Solaar can emulate an `XF86_MonBrightnessDown` key tap

lib/logitech_receiver/diversion.py

@@ -25,12 +25,7 @@ from logging import getLogger
 
 import _thread
 import psutil
-import Xlib
 
-from Xlib import X
-from Xlib.display import Display
-from Xlib.ext import record
-from Xlib.protocol import rq
 from yaml import add_representer as _yaml_add_representer
 from yaml import dump_all as _yaml_dump_all
 from yaml import safe_load_all as _yaml_safe_load_all
@@ -42,7 +37,21 @@ from .special_keys import CONTROL as _CONTROL
 _log = getLogger(__name__)
 del getLogger
 
-Xlib.XK.load_keysym_group('xf86')
+# many of the rule features require X11 so turn rule processing off if X11 is not available
+try:
+    import Xlib
+    from Xlib import X
+    from Xlib.display import Display
+    from Xlib.ext import record
+    from Xlib.protocol import rq
+    from Xlib import XK as _XK
+    _XK.load_keysym_group('xf86')
+    XK_KEYS = vars(_XK)
+    x11 = True
+except Exception:
+    _log.warn('Xlib not available - rules will not be activated')
+    XK_KEYS = {}
+    x11 = False
 
 # determine name of active process
 
@@ -118,6 +127,7 @@ def key_press_handler(reply):
             current_key_modifiers = event.state & ~(1 << mod) if mod is not None else event.state
 
 
+if x11:
     _thread.start_new_thread(display.record_enable_context, (context, key_press_handler))
 # display.record_free_context(context)  when should this be done??
 
@@ -578,28 +588,23 @@ COMPONENTS = {
     'Execute': Execute,
 }
 
-
+built_in_rules = Rule([])
+if x11:
     built_in_rules = Rule([
-    ## Some malformed Rules for testing
-    ##    Rule([Process(0), Feature(0), Modifiers(['XX', 0]), Modifiers('XXX'), Modifiers([0]),
-    ##         KeyPress(['XXXXX', 0]), KeyPress(['XXXXXX']), KeyPress(0),
-    ##         MouseScroll(0), MouseScroll([0, 0, 0]), MouseScroll(['a', 0]),
-    ##         Rule(["XXXXXXX"])]),
-    ##    Rule([Feature(0)]),
-    ##    Rule([Modifiers(['XXXXXXXXX', 0])]),
-    ##    Rule([KeyPress(['XXXXXSSSSS', 0])]),
         {'Rule': [  # Implement problematic keys for Craft and MX Master
             {'Feature': 'REPROG_CONTROLS_V4'},
             {'Report': 0x0},
             {'Rule': [{'Key': 'Brightness Down'}, {'KeyPress': 'XF86_MonBrightnessDown'}]},
             {'Rule': [{'Key': 'Brightness Up'}, {'KeyPress': 'XF86_MonBrightnessUp'}]},
         ]},
-    {'Rule': [  # In firefox, crown movements emits keys that move up and down if not pressed, rotate through tabs otherwise
+        {'Rule': [  # In firefox, crown emits keys that move up and down if not pressed, rotate through tabs otherwise
             {'Process': 'firefox'},
             {'Feature': 'CROWN'},
             {'Report': 0x0},
             {'Rule': [{'Test': 'crown_pressed'}, {'Test': 'crown_right_ratchet'}, {'KeyPress': ['Control_R', 'Tab']}]},
-        {'Rule': [{'Test': 'crown_pressed'}, {'Test': 'crown_left_ratchet'}, {'KeyPress': ['Control_R', 'Shift_R', 'Tab']}]},
+            {'Rule': [{'Test': 'crown_pressed'},
+                      {'Test': 'crown_left_ratchet'},
+                      {'KeyPress': ['Control_R', 'Shift_R', 'Tab']}]},
             {'Rule': [{'Test': 'crown_right_ratchet'}, {'KeyPress': 'Down'}]},
             Rule([Test('crown_left_ratchet'), KeyPress(['Up'])]),
         ]},
@@ -621,6 +626,8 @@ built_in_rules = Rule([
 
 # process a notification
 def process_notification(device, status, notification, feature):
+    if not x11:
+        return
     global keys_down, key_down
     key_down = None
     # need to keep track of keys that are down to find a new key down

lib/solaar/ui/diversion_rules.py

@@ -24,10 +24,9 @@ from contextlib import contextmanager as contextlib_contextmanager
 from logging import getLogger
 from shlex import quote as shlex_quote
 
-import Xlib.XK
-
 from gi.repository import Gdk, GObject, Gtk
 from logitech_receiver import diversion as _DIV
+from logitech_receiver.diversion import XK_KEYS as _XK_KEYS
 from logitech_receiver.diversion import buttons as _buttons
 from logitech_receiver.hidpp20 import FEATURE as _ALL_FEATURES
 from logitech_receiver.special_keys import CONTROL as _CONTROL
@@ -1086,7 +1085,7 @@ class ActionUI(RuleComponentUI):
 class KeyPressUI(ActionUI):
 
     CLASS = _DIV.KeyPress
-    KEY_NAMES = [k[3:] if k.startswith('XK_') else k for k, v in vars(Xlib.XK).items() if isinstance(v, int)]
+    KEY_NAMES = [k[3:] if k.startswith('XK_') else k for k, v in _XK_KEYS.items() if isinstance(v, int)]
 
     def create_widgets(self):
         self.widgets = {}