-----------------------------------------------------------------------------
-- |
-- Module : XMonad.Hooks.DebugKeyEvents
-- Copyright : (c) 2011 Brandon S Allbery <allbery.b@gmail.com>
-- License : BSD
--
-- Maintainer : Brandon S Allbery <allbery.b@gmail.com>
-- Stability : unstable
-- Portability : unportable
--
-- A debugging module to track key events, useful when you can't tell whether
-- xmonad is processing some or all key events.
-----------------------------------------------------------------------------
module XMonad.Hooks.DebugKeyEvents (-- * Usage
-- $usage
debugKeyEvents
) where
import XMonad.Core
import XMonad.Operations (cleanMask)
import Graphics.X11.Xlib
import Graphics.X11.Xlib.Extras
import Control.Monad.State (gets)
import Data.Bits
import Data.List (intercalate)
import Data.Monoid
import Numeric (showHex)
import System.IO (hPutStrLn
,stderr)
-- $usage
-- Add this to your handleEventHook to print received key events to the
-- log (the console if you use @startx@/@xinit@, otherwise usually
-- @~/.xsession-errors@).
--
-- > , handleEventHook = debugKeyEvents
--
-- If you already have a handleEventHook then you should append it:
--
-- > , handleEventHook = ... <+> debugKeyEvents
--
-- Logged key events look like:
--
-- @keycode 53 sym 120 (0x78, "x") mask 0x0 () clean 0x0 ()@
--
-- The @mask@ and @clean@ indicate the modifiers pressed along with
-- the key; @mask@ is raw, and @clean@ is what @xmonad@ sees after
-- sanitizing it (removing @numberLockMask@, etc.)
--
-- For more detailed instructions on editing the logHook see:
--
-- "XMonad.Doc.Extending#The_log_hook_and_external_status_bars"
-- | Print key events to stderr for debugging
debugKeyEvents :: Event -> X All
debugKeyEvents (KeyEvent {ev_event_type = t, ev_state = m, ev_keycode = code})
| t == keyPress =
withDisplay $ \dpy -> do
sym <- io $ keycodeToKeysym dpy code 0
msk <- cleanMask m
nl <- gets numberlockMask
io $ hPutStrLn stderr $ intercalate " " ["keycode"
,show code
,"sym"
,show sym
," ("
,hex sym
," \""
,keysymToString sym
,"\") mask"
,hex m
,"(" ++ vmask nl m ++ ")"
,"clean"
,hex msk
,"(" ++ vmask nl msk ++ ")"
]
return (All True)
debugKeyEvents _ = return (All True)
-- | Convenient showHex variant
hex :: (Integral n, Show n) => n -> String
hex v = "0x" ++ showHex v ""
-- | Convert a modifier mask into a useful string
vmask :: KeyMask -> KeyMask -> String
vmask numLockMask msk = intercalate " " $
reverse $
fst $
foldr vmask' ([],msk) masks
where
masks = map (\m -> (m,show m)) [0..toEnum (bitSize msk - 1)] ++
[(numLockMask,"num" )
,( lockMask,"lock" )
,(controlMask,"ctrl" )
,( shiftMask,"shift")
,( mod5Mask,"mod5" )
,( mod4Mask,"mod4" )
,( mod3Mask,"mod3" )
,( mod2Mask,"mod2" )
,( mod1Mask,"mod1" )
]
vmask' _ a@( _,0) = a
vmask' (m,s) (ss,v) | v .&. m == m = (s:ss,v .&. complement m)
vmask' _ r = r
