Move signal handler and data types to own module

This is necessary to make SignalType available for other modules without
import loops. This also decoupels the modules and their functionality a
bit more so this is generally a cleaner solution.

2 files changed, 34 insertions, 24 deletions

diff --git a/src/Signal.hs b/src/Signal.hs
new file mode 100644
index 0000000..3919d86
--- /dev/null
+++ b/src/Signal.hs
@@ -0,0 +1,33 @@
+{-# LANGUAGE DeriveDataTypeable #-}
+
+module Signal where
+
+import Data.Typeable (Typeable)
+import Control.Concurrent
+import Control.Exception hiding (handle)
+import System.Posix.Signals
+
+data WakeUp = WakeUp deriving (Show,Typeable)
+instance Exception WakeUp
+
+data SignalType = Wakeup
+                | Reposition
+                | ChangeScreen
+
+-- | Signal handling
+setupSignalHandler :: IO (MVar SignalType)
+setupSignalHandler = do
+   tid   <- newEmptyMVar
+   installHandler sigUSR2 (Catch $ updatePosHandler tid) Nothing
+   installHandler sigUSR1 (Catch $ changeScreenHandler tid) Nothing
+   return tid
+
+updatePosHandler :: MVar SignalType -> IO ()
+updatePosHandler sig = do
+   putMVar sig Reposition
+   return ()
+
+changeScreenHandler :: MVar SignalType -> IO ()
+changeScreenHandler sig = do
+   putMVar sig ChangeScreen
+   return ()
diff --git a/src/Xmobar.hs b/src/Xmobar.hs
index 0b744de..6c2965c 100644
--- a/src/Xmobar.hs
+++ b/src/Xmobar.hs
@@ -39,7 +39,7 @@ import Control.Arrow ((&&&))
 import Control.Monad.Reader
 import Control.Concurrent
 import Control.Concurrent.STM
-import Control.Exception hiding (handle)
+import Control.Exception (catch, SomeException(..))
 import Data.Bits
 
 import Config
@@ -70,11 +70,6 @@ data XConf =
 runX :: XConf -> X () -> IO ()
 runX xc f = runReaderT f xc
 
-data WakeUp = WakeUp deriving (Show,Typeable)
-instance Exception WakeUp
-
-data SignalType = Wakeup | Reposition | ChangeScreen
-
 -- | Starts the main event loop and threads
 startLoop :: XConf -> [[(Maybe ThreadId, TVar String)]] -> IO ()
 startLoop xcfg@(XConf _ _ w _ _) vs = do
@@ -162,24 +157,6 @@ eventLoop tv xc@(XConf d _ w fs cfg) signal = do
               return (ocfg {position = OnScreen 1 o})
 
 
--- | Signal handling
-setupSignalHandler :: IO (MVar SignalType)
-setupSignalHandler = do
-   tid   <- newEmptyMVar
-   installHandler sigUSR2 (Catch $ updatePosHandler tid) Nothing
-   installHandler sigUSR1 (Catch $ changeScreenHandler tid) Nothing
-   return tid
-
-updatePosHandler :: MVar SignalType -> IO ()
-updatePosHandler sig = do
-   putMVar sig Reposition
-   return ()
-
-changeScreenHandler :: MVar SignalType -> IO ()
-changeScreenHandler sig = do
-   putMVar sig ChangeScreen
-   return ()
-
 -- $command
 
 -- | Runs a command as an independent thread and returns its thread id