tv xmonad service: save state on shutdown

2 files changed, 64 insertions, 7 deletions

diff --git a/tv/2configs/xserver/xmonad/Main.hs b/tv/2configs/xserver/xmonad/Main.hs
index cca2902a0..6e0be0579 100644
--- a/tv/2configs/xserver/xmonad/Main.hs
+++ b/tv/2configs/xserver/xmonad/Main.hs
@@ -1,9 +1,11 @@
 {-# LANGUAGE DeriveDataTypeable #-} -- for XS
+{-# LANGUAGE LambdaCase #-}
 
 
 module Main where
 
 import XMonad
+import System.Environment (getArgs)
 import XMonad.Prompt (defaultXPConfig)
 import XMonad.Actions.DynamicWorkspaces ( addWorkspacePrompt, renameWorkspace
                                         , removeEmptyWorkspace)
@@ -30,6 +32,7 @@ import XMonad.Layout.PerWorkspace (onWorkspace)
 import Util.Pager
 import Util.Rhombus
 import Util.Debunk
+import Util.Shutdown
 
 
 --data MyState = MyState deriving Typeable
@@ -48,11 +51,12 @@ myFont :: String
 myFont = "-schumacher-*-*-*-*-*-*-*-*-*-*-*-iso10646-*"
 
 main :: IO ()
-main = do
-    -- TODO exec (shlex "xrdb -merge" ++ [HOME ++ "/.Xresources"])
-    -- TODO exec (shlex "xsetroot -solid '#1c1c1c'")
-    --spawn "xrdb -merge \"$HOME/.Xresources\""
-    --spawn "xsetroot -solid '#1c1c1c'"
+main = getArgs >>= \case
+    ["--shutdown"] -> sendShutdownEvent
+    _ -> mainNoArgs
+
+mainNoArgs :: IO ()
+mainNoArgs = do
     xmonad
         -- $ withUrgencyHookC dzenUrgencyHook { args = ["-bg", "magenta", "-fg", "magenta", "-h", "2"], duration = 500000 }
         --                   urgencyConfig { remindWhen = Every 1 }
@@ -80,6 +84,7 @@ main = do
             , startupHook       = spawn "echo emit XMonadStartup"
             , normalBorderColor  = "#1c1c1c"
             , focusedBorderColor = "#f000b0"
+            , handleEventHook = handleShutdownEvent
             }
   where
     myLayout =
@@ -118,8 +123,7 @@ spawnTermAt _    = spawn myTerm
 
 myKeys :: XConfig Layout -> Map (KeyMask, KeySym) (X ())
 myKeys conf = Map.fromList $
-    [ ((_4C , xK_Delete ), spawn "make -C $HOME/.xmonad reload")
-    , ((_4  , xK_Escape ), spawn "/var/setuid-wrappers/slock")
+    [ ((_4  , xK_Escape ), spawn "/var/setuid-wrappers/slock")
     , ((_4S , xK_c      ), kill)
 
     , ((_4  , xK_x      ), chooseAction spawnTermAt)
diff --git a/tv/2configs/xserver/xmonad/Util/Shutdown.hs b/tv/2configs/xserver/xmonad/Util/Shutdown.hs
new file mode 100644
index 000000000..c5a3edb80
--- /dev/null
+++ b/tv/2configs/xserver/xmonad/Util/Shutdown.hs
@@ -0,0 +1,53 @@
+{-# LANGUAGE LambdaCase #-}
+module Util.Shutdown
+    ( sendShutdownEvent
+    , handleShutdownEvent
+    , shutdown
+    )
+  where
+
+import Control.Monad
+import Data.Monoid
+import Data.Maybe (catMaybes)
+import qualified Data.Map as Map
+import System.Environment (getEnv)
+import System.Exit (exitSuccess)
+import XMonad
+import qualified XMonad.StackSet as W
+
+sendShutdownEvent :: IO ()
+sendShutdownEvent = do
+    dpy <- openDisplay ""
+    rw <- rootWindow dpy $ defaultScreen dpy
+    a <- internAtom dpy "XMONAD_SHUTDOWN" False
+    allocaXEvent $ \e -> do
+        setEventType e clientMessage
+        setClientMessageEvent e rw a 32 0 currentTime
+        sendEvent dpy rw False structureNotifyMask e
+    sync dpy False
+
+handleShutdownEvent :: Event -> X All
+handleShutdownEvent = \case
+  ClientMessageEvent { ev_message_type = mt } -> do
+    c <- (mt ==) <$> getAtom "XMONAD_SHUTDOWN"
+    when c shutdown
+    return (All c)
+  _ ->
+    return (All True)
+
+shutdown :: X ()
+shutdown = do
+  broadcastMessage ReleaseResources
+  io . flush =<< asks display
+  let wsData = show . W.mapLayout show . windowset
+      maybeShow (t, Right (PersistentExtension ext)) = Just (t, show ext)
+      maybeShow (t, Left str) = Just (t, str)
+      maybeShow _ = Nothing
+      extState =
+        return . show . catMaybes . map maybeShow . Map.toList . extensibleState
+  s <- gets (\s -> (wsData s : extState s))
+  _ <- io $ do
+    path <- getEnv "XMONAD_STATE"
+    writeFile path (concatMap (++"\n") s)
+    exitSuccess
+  return ()