1 files changed, 11 insertions, 9 deletions

diff --git a/trivmix/Trivmix.hs b/trivmix/Trivmix.hs
index 7c18965..b9474f2 100644
--- a/trivmix/Trivmix.hs
+++ b/trivmix/Trivmix.hs
@@ -172,11 +172,12 @@ trivmix Options{..} = do
   level <- newMVar initialLevel
   balance <- newMVar initialBalance
   level' <- newMVar 0
+  stderrLock <- newEmptyMVar
   let withFiles = foldl (.) id $ map (\f -> onStateFile f (show initialLevel ++ "\n")) levelFiles
                               ++ map (\f -> onStateFile f (show initialBalance ++ "\n")) balanceFiles
   withFiles $ withINotify $ \inotify -> do
     handleFiles inotify level levelFiles
-    handleFiles inotify balance levelFiles
+    handleFiles inotify balance balanceFiles
     Jack.handleExceptions $
       Jack.withClientDefault client $ \client' ->
       Jack.withPort client' input $ \input' ->
@@ -196,18 +197,19 @@ trivmix Options{..} = do
             currentLevel <- (\(CFloat f) -> Lin . either error id . refine $ realToFrac f) <$> readMVar level'
             case compare currentLevel newLevel of
               EQ -> threadDelay . round $ interval * 1e6
-              _  -> mapM_ (\x -> (swapMVar level' $! toRealFloat . unrefine . toLin $ linInt' x currentLevel newLevel) >> threadDelay delay) (takeWhile (<= 1) $ iterate (+ recip frames) 0)
+              _  -> do
+                mapM_ (\x -> (swapMVar level' $! toRealFloat . unrefine . toLin $ linInt' x currentLevel newLevel) >> threadDelay delay) (takeWhile (<= 1) $ iterate (+ recip frames) 0)
+                withMVarLock stderrLock . hPutStrLn stderr $ "Finished smooth transition from ‘" ++ show currentLevel ++ "’ to ‘" ++ show newLevel ++ "’."
           notifyReady
           forever $ threadDelay (round $ watchdogInterval * 1e6) >> notifyWatchdog
 
 mix :: MVar CFloat -> CFloat -> IO CFloat
 mix level input = (input *) <$> readMVar level
 
-handleFiles :: (Read l, Show l, Eq l) => INotify -> MVar l -> [FilePath] -> IO ()
-handleFiles inotify level files = do
+handleFiles :: (Read l, Show l, Eq l) => INotify -> MVar l -> MVar () -> [FilePath] -> IO ()
+handleFiles inotify level stderrLock files = do
   initLevel <- readMVar level
   levelChanges <- newChan
-  stderrLock <- newEmptyMVar
   let 
     handleFile file = addWatch inotify watchedAttrs file (const $ readLevel levelChanges level file stderrLock)
   mapM_ handleFile files
@@ -227,19 +229,19 @@ onStateFile file initial action = do
   setFileCreationMask nullFileMode
   let acquireFile = case exists of
         True -> return ()
-        False -> do
+        False -> withMVarLock stderrLock $ do
           hPutStrLn stderr $ "Creating ‘" ++ file ++ "’ (file)"
           createFile file defFileMode >>= closeFd >> writeFile file initial
       releaseFile = case exists of
         True -> return ()
-        False -> do
+        False -> withMVarLock stderrLock $ do
           hPutStrLn stderr $ "Removing ‘" ++ file ++ "’ (file)"
           removeFile file
-      acquireDir = (flip mapM) (reverse createDirs) $ \directory -> do
+      acquireDir = (flip mapM) (reverse createDirs) $ \directory -> withMVarLock stderrLock $ do
           hPutStrLn stderr $ "Creating ‘" ++ directory ++ "’ (dir)"
           createDirectory directory
           setFileMode directory defDirectoryMode
-      releaseDir = (flip mapM) createDirs $ \directory -> do
+      releaseDir = (flip mapM) createDirs $ \directory -> withMVarLock stderrLock $ do
           hPutStrLn stderr $ "Removing ‘" ++ directory ++ "’ (dir)"
           removeDirectory directory
       acquire = acquireDir >> acquireFile