Determine numlockMask automatically, fixes #120

XMonad/Config.hs

@@ -25,11 +25,11 @@ module XMonad.Config (defaultConfig) where
 -- Useful imports
 --
 import XMonad.Core as XMonad hiding
-    (workspaces,manageHook,numlockMask,keys,logHook,startupHook,borderWidth,mouseBindings
+    (workspaces,manageHook,keys,logHook,startupHook,borderWidth,mouseBindings
     ,layoutHook,modMask,terminal,normalBorderColor,focusedBorderColor,focusFollowsMouse
     ,handleEventHook)
 import qualified XMonad.Core as XMonad
-    (workspaces,manageHook,numlockMask,keys,logHook,startupHook,borderWidth,mouseBindings
+    (workspaces,manageHook,keys,logHook,startupHook,borderWidth,mouseBindings
     ,layoutHook,modMask,terminal,normalBorderColor,focusedBorderColor,focusFollowsMouse
     ,handleEventHook)
 
@@ -64,22 +64,6 @@ workspaces = map show [1 .. 9 :: Int]
 defaultModMask :: KeyMask
 defaultModMask = mod1Mask
 
--- | The mask for the numlock key. Numlock status is "masked" from the
--- current modifier status, so the keybindings will work with numlock on or
--- off. You may need to change this on some systems.
---
--- You can find the numlock modifier by running "xmodmap" and looking for a
--- modifier with Num_Lock bound to it:
---
--- > $ xmodmap | grep Num
--- > mod2        Num_Lock (0x4d)
---
--- Set numlockMask = 0 if you don't have a numlock key, or want to treat
--- numlock status separately.
---
-numlockMask :: KeyMask
-numlockMask = mod2Mask
-
 -- | Width of the window border in pixels.
 --
 borderWidth :: Dimension
@@ -256,7 +240,6 @@ defaultConfig = XConfig
     , XMonad.terminal           = terminal
     , XMonad.normalBorderColor  = normalBorderColor
     , XMonad.focusedBorderColor = focusedBorderColor
-    , XMonad.numlockMask        = numlockMask
     , XMonad.modMask            = defaultModMask
     , XMonad.keys               = keys
     , XMonad.logHook            = logHook

XMonad/Core.hs

@@ -64,12 +64,14 @@ data XState = XState
     , mapped           :: !(S.Set Window)                -- ^ the Set of mapped windows
     , waitingUnmap     :: !(M.Map Window Int)            -- ^ the number of expected UnmapEvents
     , dragging         :: !(Maybe (Position -> Position -> X (), X ()))
+    , numlockMask  :: !KeyMask                           -- ^ The numlock modifier
     , extensibleState  :: !(M.Map String (Either String StateExtension))
     -- ^ stores custom state information.
     --
     -- The module XMonad.Utils.ExtensibleState in xmonad-contrib
     -- provides additional information and a simple interface for using this.
     }
+
 -- | XConf, the (read-only) window manager configuration.
 data XConf = XConf
     { display       :: Display        -- ^ the X11 display
@@ -98,7 +100,6 @@ data XConfig l = XConfig
                                                  -- should also be run afterwards. mappend should be used for combining
                                                  -- event hooks in most cases.
     , workspaces         :: ![String]            -- ^ The list of workspaces' names
-    , numlockMask        :: !KeyMask             -- ^ The numlock modifier
     , modMask            :: !KeyMask             -- ^ the mod modifier
     , keys               :: !(XConfig Layout -> M.Map (ButtonMask,KeySym) (X ()))
                                                  -- ^ The key binding: a map from key presses and actions

XMonad/Main.hsc

@@ -121,6 +121,7 @@ xmonad initxmc = do
 
         st = XState
             { windowset       = initialWinset
+            , numlockMask   = 0
             , mapped          = S.empty
             , waitingUnmap    = M.empty
             , dragging        = Nothing
@@ -129,6 +130,7 @@ xmonad initxmc = do
     allocaXEvent $ \e ->
         runX cf st $ do
 
+            setNumlockMask
             grabKeys
             grabButtons
 
@@ -218,7 +220,9 @@ handle (UnmapEvent {ev_window = w, ev_send_event = synthetic}) = whenX (isClient
 -- set keyboard mapping
 handle e@(MappingNotifyEvent {}) = do
     io $ refreshKeyboardMapping e
-    when (ev_request e == mappingKeyboard) grabKeys
+    when (ev_request e `elem` [mappingKeyboard, mappingModifier]) $ do
+        setNumlockMask
+        grabKeys
 
 -- handle button release, which may finish dragging.
 handle e@(ButtonEvent {ev_event_type = t})
@@ -324,6 +328,18 @@ scan dpy rootw = do
                   return $ not (wa_override_redirect wa)
                          && (wa_map_state wa == waIsViewable || ic)
 
+setNumlockMask :: X ()
+setNumlockMask = do
+    dpy <- asks display
+    ms <- io $ getModifierMapping dpy
+    xs <- sequence [ do
+                        ks <- io $ keycodeToKeysym dpy kc 0
+                        if ks == xK_Num_Lock
+                            then return (setBit 0 (fromIntegral m))
+                            else return (0 :: KeyMask)
+                        | (m, kcs) <- ms, kc <- kcs, kc /= 0]
+    modify (\s -> s { numlockMask = foldr (.|.) 0 xs })
+
 -- | Grab the keys back
 grabKeys :: X ()
 grabKeys = do

XMonad/Operations.hs

@@ -389,13 +389,13 @@ isClient w = withWindowSet $ return . W.member w
 -- (numlock and capslock)
 extraModifiers :: X [KeyMask]
 extraModifiers = do
-    nlm <- asks (numlockMask . config)
+    nlm <- gets numlockMask
     return [0, nlm, lockMask, nlm .|. lockMask ]
 
 -- | Strip numlock\/capslock from a mask
 cleanMask :: KeyMask -> X KeyMask
 cleanMask km = do
-    nlm <- asks (numlockMask . config)
+    nlm <- gets numlockMask
     return (complement (nlm .|. lockMask) .&. km)
 
 -- | Get the 'Pixel' value for a named color

man/xmonad.hs

@@ -34,21 +34,6 @@ myBorderWidth   = 1
 --
 myModMask       = mod1Mask
 
--- The mask for the numlock key. Numlock status is "masked" from the
--- current modifier status, so the keybindings will work with numlock on or
--- off. You may need to change this on some systems.
---
--- You can find the numlock modifier by running "xmodmap" and looking for a
--- modifier with Num_Lock bound to it:
---
--- > $ xmodmap | grep Num
--- > mod2        Num_Lock (0x4d)
---
--- Set numlockMask = 0 if you don't have a numlock key, or want to treat
--- numlock status separately.
---
-myNumlockMask   = mod2Mask
-
 -- The default number of workspaces (virtual screens) and their names.
 -- By default we use numeric strings, but any string may be used as a
 -- workspace name. The number of workspaces is determined by the length
@@ -272,7 +257,6 @@ defaults = defaultConfig {
         focusFollowsMouse  = myFocusFollowsMouse,
         borderWidth        = myBorderWidth,
         modMask            = myModMask,
-        numlockMask        = myNumlockMask,
         workspaces         = myWorkspaces,
         normalBorderColor  = myNormalBorderColor,
         focusedBorderColor = myFocusedBorderColor,