Refactoring: Xmobar.System

1 files changed, 73 insertions, 0 deletions

diff --git a/src/lib/Xmobar/System/DBus.hs b/src/lib/Xmobar/System/DBus.hs
new file mode 100644
index 0000000..103a5a9
--- /dev/null
+++ b/src/lib/Xmobar/System/DBus.hs
@@ -0,0 +1,73 @@
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  DBus
+-- Copyright   :  (c) Jochen Keil
+-- License     :  BSD-style (see LICENSE)
+--
+-- Maintainer  :  Jochen Keil <jochen dot keil at gmail dot com>
+-- Stability   :  unstable
+-- Portability :  unportable
+--
+-- DBus IPC module for Xmobar
+--
+-----------------------------------------------------------------------------
+
+module Xmobar.System.DBus (runIPC) where
+
+import DBus
+import DBus.Client hiding (interfaceName)
+import qualified DBus.Client as DC
+import Data.Maybe (isNothing)
+import Control.Concurrent.STM
+import Control.Exception (handle)
+import System.IO (stderr, hPutStrLn)
+import Control.Monad.IO.Class (liftIO)
+
+import Xmobar.System.Signal
+
+busName :: BusName
+busName = busName_ "org.Xmobar.Control"
+
+objectPath :: ObjectPath
+objectPath = objectPath_ "/org/Xmobar/Control"
+
+interfaceName :: InterfaceName
+interfaceName = interfaceName_ "org.Xmobar.Control"
+
+runIPC :: TMVar SignalType -> IO ()
+runIPC mvst = handle printException exportConnection
+    where
+    printException :: ClientError -> IO ()
+    printException = hPutStrLn stderr . clientErrorMessage
+    exportConnection = do
+        client <- connectSession
+        requestName client busName [ nameDoNotQueue ]
+        export client objectPath defaultInterface
+          { DC.interfaceName = interfaceName
+          , DC.interfaceMethods = [ sendSignalMethod mvst ]
+          }
+
+sendSignalMethod :: TMVar SignalType -> Method
+sendSignalMethod mvst = makeMethod sendSignalName
+    (signature_ [variantType $ toVariant (undefined :: SignalType)])
+    (signature_ [])
+    sendSignalMethodCall
+    where
+    sendSignalName :: MemberName
+    sendSignalName = memberName_ "SendSignal"
+
+    sendSignalMethodCall :: MethodCall -> DBusR Reply
+    sendSignalMethodCall mc = liftIO $
+        if methodCallMember mc == sendSignalName
+          then do
+            let signals :: [Maybe SignalType]
+                signals = map fromVariant (methodCallBody mc)
+            mapM_ sendSignal signals
+            if any isNothing signals
+              then return ( ReplyError errorInvalidParameters [] )
+              else return ( ReplyReturn [] )
+          else
+            return ( ReplyError errorUnknownMethod [] )
+
+    sendSignal :: Maybe SignalType -> IO ()
+    sendSignal = maybe (return ()) (atomically . putTMVar mvst)