ensure that direct mode file is not modified while generating its key

Command/Add.hs

@@ -73,24 +73,36 @@ lockDown file = do
 ingest :: KeySource -> Annex (Maybe Key)
 ingest source = do
 	backend <- chooseBackend $ keyFilename source
-	genKey source backend >>= go
-  where
-	go Nothing = do
-		liftIO $ nukeFile $ contentLocation source
-		return Nothing
-	go (Just (key, _)) = do
 	ifM isDirect
 		( do
-				updateCache key $ keyFilename source
+			mstat <- liftIO $ catchMaybeIO $ getSymbolicLinkStatus $ keyFilename source
-				void $ addAssociatedFile key $ keyFilename source
+			k <- genKey source backend
-				liftIO $ allowWrite $ keyFilename source
+			godirect k (toCache =<< mstat)
-				liftIO $ nukeFile $ contentLocation source
+		, go =<< genKey source backend
-			, do
+		)
+  where
+	go (Just (key, _)) = do
 		handle (undo (keyFilename source) key) $
 			moveAnnex key $ contentLocation source
 		liftIO $ nukeFile $ keyFilename source
-			)
 		return $ Just key
+	go Nothing = failure
+
+	godirect (Just (key, _)) (Just cache) =
+		ifM (compareCache (keyFilename source) $ Just cache)
+			( do
+				writeCache key cache
+				void $ addAssociatedFile key $ keyFilename source
+				liftIO $ allowWrite $ keyFilename source
+				liftIO $ nukeFile $ contentLocation source
+				return $ Just key
+			, failure
+			)
+	godirect _ _ = failure
+
+	failure = do
+		liftIO $ nukeFile $ contentLocation source
+		return Nothing		
 
 perform :: FilePath -> CommandPerform
 perform file =