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Diffstat (limited to 'XMonad')
| -rw-r--r-- | XMonad/Layout/Stoppable.hs | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/XMonad/Layout/Stoppable.hs b/XMonad/Layout/Stoppable.hs new file mode 100644 index 0000000..35c3c01 --- /dev/null +++ b/XMonad/Layout/Stoppable.hs @@ -0,0 +1,130 @@ +{-# LANGUAGE MultiParamTypeClasses, TypeSynonymInstances #-} +{-# LANGUAGE PatternGuards #-} +----------------------------------------------------------------------------- +-- | +-- Module : XMonad.Layout.Stoppable +-- Copyright : (c) Anton Vorontsov <anton@enomsg.org> 2014 +-- License : BSD-style (as xmonad) +-- +-- Maintainer : Anton Vorontsov <anton@enomsg.org> +-- Stability : unstable +-- Portability : unportable +-- +-- This module implements a special kind of layout modifier, which when +-- applied to a layout, causes xmonad to stop all non-visible processes. +-- In a way, this is a sledge-hammer for applications that drain power. +-- For example, given a web browser on a stoppable workspace, once the +-- workspace is hidden the web browser will be stopped. +-- +-- Note that the stopped application won't be able to communicate with X11 +-- clipboard. For this, the module actually stops applications after a +-- certain delay, giving a chance for a user to complete copy-paste +-- sequence. By default, the delay equals to 15 seconds, it is +-- configurable via 'Stoppable' constructor. +-- +-- The stoppable modifier prepends a mark (by default equals to +-- \"Stoppable\") to the layout description (alternatively, you can choose +-- your own mark and use it with 'Stoppable' constructor). The stoppable +-- layout (identified by a mark) spans to multiple workspaces, letting you +-- to create groups of stoppable workspaces that only stop processes when +-- none of the workspaces are visible, and conversely, unfreezing all +-- processes even if one of the stoppable workspaces are visible. +-- +-- To stop the process we use signals, which works for most cases. For +-- processes that tinker with signal handling (debuggers), another +-- (Linux-centric) approach may be used. See +-- <https://www.kernel.org/doc/Documentation/cgroups/freezer-subsystem.txt> +-- +----------------------------------------------------------------------------- + +module XMonad.Layout.Stoppable + ( -- $usage + Stoppable(..) + , stoppable + ) where + +import XMonad +import XMonad.Actions.WithAll +import XMonad.Util.WindowProperties +import XMonad.Util.Timer +import XMonad.StackSet hiding (filter) +import XMonad.Layout.LayoutModifier +import System.Posix.Env +import System.Posix.Signals +import Data.Maybe +import Control.Monad + +-- $usage +-- You can use this module with the following in your @~\/.xmonad\/xmonad.hs@: +-- +-- > import XMonad +-- > import XMonad.Layout.Stoppable +-- > +-- > main = xmonad def +-- > { layoutHook = layoutHook def ||| stoppable (layoutHook def) } +-- +-- Note that the module has to distinguish between local and remote +-- proccesses, which means that it needs to know the hostname, so it looks +-- for environment variables (e.g. HOST). +-- +-- Beware that as of now this module does not support dynamically changing +-- hostnames. +-- +-- For more detailed instructions on editing the layoutHook see: +-- +-- "XMonad.Doc.Extending#Editing_the_layout_hook" + +signalWindow :: Signal -> Window -> X () +signalWindow s w = do + pid <- getProp32s "_NET_WM_PID" w + io $ (signalProcess s . fromIntegral) `mapM_` fromMaybe [] pid + +signalLocalWindow :: Signal -> Window -> X () +signalLocalWindow s w = do + host <- io $ pickOneMaybe `liftM` (getEnv `mapM` vars) + hasProperty (Machine host) w >>= flip when (signalWindow s w) + where + pickOneMaybe = last . (mzero:) . take 1 . catMaybes + vars = ["XAUTHLOCALHOSTNAME","HOST","HOSTNAME"] + +withAllOn :: (a -> X ()) -> Workspace i l a -> X () +withAllOn f wspc = f `mapM_` integrate' (stack wspc) + +withAllFiltered :: (Workspace i l a -> Bool) + -> [Workspace i l a] + -> (a -> X ()) -> X () +withAllFiltered p wspcs f = withAllOn f `mapM_` filter p wspcs + +sigStoppableWorkspacesHook :: String -> X () +sigStoppableWorkspacesHook k = do + ws <- gets windowset + withAllFiltered isStoppable (hidden ws) (signalLocalWindow sigSTOP) + where + isStoppable ws = k `elem` words (description $ layout ws) + +-- | Data type for ModifiedLayout. The constructor lets you to specify a +-- custom mark/description modifier and a delay. You can also use +-- 'stoppable' helper function. +data Stoppable a = Stoppable + { mark :: String + , delay :: Rational + , timer :: Maybe TimerId + } deriving (Show,Read) + +instance LayoutModifier Stoppable Window where + modifierDescription = mark + + hook _ = withAll $ signalLocalWindow sigCONT + + handleMess (Stoppable m _ (Just tid)) msg + | Just ev <- fromMessage msg = handleTimer tid ev run + where run = sigStoppableWorkspacesHook m >> return Nothing + handleMess (Stoppable m d _) msg + | Just Hide <- fromMessage msg = + (Just . Stoppable m d . Just) `liftM` startTimer d + | otherwise = return Nothing + +-- | Convert a layout to a stoppable layout using the default mark +-- (\"Stoppable\") and a delay of 15 seconds. +stoppable :: l a -> ModifiedLayout Stoppable l a +stoppable = ModifiedLayout (Stoppable "Stoppable" 15 Nothing) |