fix feed function from Handle

haskell/msgpack.cabal

@@ -1,5 +1,5 @@
 Name:                msgpack
-Version:             0.2.0
+Version:             0.2.1
 License:             BSD3
 License-File:        LICENSE
 Author:              Hideyuki Tanaka

haskell/src/Data/MessagePack/Feed.hs

@@ -33,12 +33,16 @@ type Feeder = IO (Maybe ByteString)
 -- | Feeder from Handle
 feederFromHandle :: Handle -> IO Feeder
 feederFromHandle h = return $ do
-  bs <- BS.hGet h bufSize
+  bs <- BS.hGetNonBlocking h bufSize
   if BS.length bs > 0
-    then return $ Just bs
+    then do return $ Just bs
     else do
-    hClose h
-    return Nothing
+    bs <- BS.hGet h 1
+    if BS.length bs > 0
+      then do return $ Just bs
+      else do
+      hClose h
+      return Nothing
   where
     bufSize = 4096
 

haskell/src/Data/MessagePack/Monad.hs

@@ -115,19 +115,22 @@ instance MonadIO m => MonadIO (UnpackerT m) where
 
 instance MonadIO m => MonadUnpacker (UnpackerT m) where
   get = UnpackerT $ \up feed -> liftIO $ do
-    resp <- unpackerExecute up
-    guard $ resp>=0
-    when (resp==0) $ do
-      Just bs <- feed
-      unpackerFeed up bs
-      resp2 <- unpackerExecute up
-      guard $ resp2==1
+    executeOne up feed
     obj <- unpackerData up
     freeZone =<< unpackerReleaseZone up
     unpackerReset up
     let Right r = fromObject obj
     return r
     
+    where
+      executeOne up feed = do
+        resp <- unpackerExecute up
+        guard $ resp>=0
+        when (resp==0) $ do
+          Just bs <- feed
+          unpackerFeed up bs
+          executeOne up feed
+
 -- | Execute deserializer using given feeder.
 unpackFrom :: MonadIO m => Feeder -> UnpackerT m r -> m r
 unpackFrom f m = do