Fix AltGr handling on modern Linux to manage Eu special symbols

lib/pynput/_util/xorg.py

@@ -27,6 +27,7 @@
 import operator
 import Xlib.display
 import Xlib.keysymdef
+import Xlib.keysymdef.xkb
 import Xlib.threaded
 import Xlib.XK
 
@@ -94,9 +95,21 @@ def _find_mask(display, symbol):
     :return: the modifier mask
     """
     # Get the key code for the symbol
-    modifier_keycode = display.keysym_to_keycode(
-        Xlib.XK.string_to_keysym(symbol)
-    )
+    keysym = Xlib.XK.string_to_keysym(symbol)
+    if not keysym:
+        # pylint: disable=W0702; we want to ignore errors
+        try:
+            keysym = getattr(Xlib.keysymdef.xkb, 'XK_' + symbol, 0)
+        except:
+            pass
+        # pylint: enable=W0702
+
+    if not keysym:
+        return 0
+
+    modifier_keycode = display.keysym_to_keycode(keysym)
+    if not modifier_keycode:
+        return 0
 
     for index, keycodes in enumerate(display.get_modifier_mapping()):
         for keycode in keycodes:
@@ -132,7 +145,10 @@ def alt_gr_mask(display):
     :return: the modifier mask
     """
     if not hasattr(display, '__altgr_mask'):
-        display.__altgr_mask = _find_mask(display, 'Mode_switch')
+        mask = _find_mask(display, 'Mode_switch')
+        if not mask:
+            mask = _find_mask(display, 'ISO_Level3_Shift')
+        display.__altgr_mask = mask
     return display.__altgr_mask
 
 

lib/pynput/keyboard/_xorg.py

@@ -208,6 +208,16 @@ def __init__(self, *args, **kwargs):
         self.ALT_GR_MASK = alt_gr_mask(self._display)
         # pylint: enable=C0103
 
+        if Key.alt_gr.value.vk:
+            try:
+                import Xlib.keysymdef.xkb as _xkb
+                if not self._display.keysym_to_keycode(Key.alt_gr.value.vk):
+                    iso_vk = getattr(_xkb, 'XK_ISO_Level3_Shift', 0)
+                    if iso_vk and self._display.keysym_to_keycode(iso_vk):
+                        Key.alt_gr.value.vk = iso_vk
+            except:
+                pass
+
     def __del__(self):
         if hasattr(self, '_display'):
             self._display.close()
@@ -518,6 +528,12 @@ class Listener(ListenerMixin, _base.Listener):
 
     #: A mapping from keysym to special key
     _SPECIAL_KEYS = {key.value.vk: key for key in Key}
+    try:
+        import Xlib.keysymdef.xkb as _xkb
+        if hasattr(_xkb, 'XK_ISO_Level3_Shift'):
+            _SPECIAL_KEYS[_xkb.XK_ISO_Level3_Shift] = Key.alt_gr
+    except (ImportError, AttributeError):
+        pass
 
     #: A mapping from numeric keypad keys to keys
     _KEYPAD_KEYS = {
@@ -565,6 +581,17 @@ def _run(self):
             super(Listener, self)._run()
 
     def _initialize(self, display):
+        # Ensure Key.alt_gr.value.vk matches the active system keysym for AltGr
+        if Key.alt_gr.value.vk:
+            try:
+                import Xlib.keysymdef.xkb as _xkb
+                if not display.keysym_to_keycode(Key.alt_gr.value.vk):
+                    iso_vk = getattr(_xkb, 'XK_ISO_Level3_Shift', 0)
+                    if iso_vk and display.keysym_to_keycode(iso_vk):
+                        Key.alt_gr.value.vk = iso_vk
+            except:
+                pass
+
         # Get the keyboard mapping to be able to translate event details to
         # key codes
         min_keycode = display.display.info.min_keycode
@@ -624,6 +651,15 @@ def _keycode_to_keysym(self, display, keycode, index):
 
         :return: a keysym
         """
+        if index & 0x2 and self._keyboard_mapping is not None:
+            try:
+                min_keycode = display.display.info.min_keycode
+                keysyms = self._keyboard_mapping[keycode - min_keycode]
+                if len(keysyms) >= 6 and keysyms[index + 2] != 0:
+                    return keysyms[index + 2]
+            except (IndexError, TypeError):
+                pass
+
         keysym = display.keycode_to_keysym(keycode, index)
         if keysym:
             return keysym