3 files changed, 38 insertions, 6 deletions
diff --git a/Assistant/Threads/TransferPoller.hs b/Assistant/Threads/TransferPoller.hs
index f8f9388f0..10ed7dd31 100644
--- a/Assistant/Threads/TransferPoller.hs
+++ b/Assistant/Threads/TransferPoller.hs
@@ -12,6 +12,7 @@ import Assistant.ThreadedMonad
 import Assistant.DaemonStatus
 import Logs.Transfer
 import Utility.NotificationBroadcaster
+import qualified Assistant.Threads.TransferWatcher as TransferWatcher
 
 import Control.Concurrent
 import qualified Data.Map as M
@@ -42,9 +43,20 @@ transferPollerThread st dstatus = thread $ do
 				sz <- catchMaybeIO $
 					fromIntegral . fileSize
 						<$> getFileStatus f
-				when (bytesComplete info /= sz && isJust sz) $
-					alterTransferInfo dstatus t $
-						\i -> i { bytesComplete = sz }
-			{- Can't poll uploads, instead the upload code
-			 - updates the files. -}
+				newsize t info sz
+			{- Uploads don't need to be polled for when the
+			 - TransferWatcher thread can track file
+			 - modifications. -}
+			| TransferWatcher.watchesTransferSize = noop
+			{- Otherwise, this code polls the upload progress
+			 - by reading the transfer info file. -}
+			| otherwise = do
+				let f = transferFile t g
+				mi <- catchDefaultIO Nothing $
+					readTransferInfoFile Nothing f
+				maybe noop (newsize t info . bytesComplete) mi
+		newsize t info sz
+			| bytesComplete info /= sz && isJust sz = 
+				alterTransferInfo dstatus t $
+					\i -> i { bytesComplete = sz }
 			| otherwise = noop
diff --git a/Assistant/Threads/TransferWatcher.hs b/Assistant/Threads/TransferWatcher.hs
index ce0708a91..d4ff9176e 100644
--- a/Assistant/Threads/TransferWatcher.hs
+++ b/Assistant/Threads/TransferWatcher.hs
@@ -30,6 +30,7 @@ transferWatcherThread st dstatus transferqueue = thread $ do
 	let hooks = mkWatchHooks
 		{ addHook = hook onAdd
 		, delHook = hook onDel
+		, modifyHook = hook onModify
 		, errHook = hook onErr
 		}
 	void $ watchDir dir (const False) hooks id
@@ -71,6 +72,25 @@ onAdd st dstatus _ file _ = case parseTransferFile file of
 				{ transferRemote = r }
 		sameuuid t r = Remote.uuid r == transferUUID t
 
+{- Called when a transfer information file is updated.
+ -
+ - The only thing that should change in the transfer info is the
+ - bytesComplete, so that's the only thing updated in the DaemonStatus. -}
+onModify :: Handler
+onModify _ dstatus _ file _ = do
+	case parseTransferFile file of
+		Nothing -> noop
+		Just t -> go t =<< readTransferInfoFile Nothing file
+	where
+		go _ Nothing = noop
+		go t (Just newinfo) = alterTransferInfo dstatus t $ \info ->
+			info { bytesComplete = bytesComplete newinfo }
+
+{- This thread can only watch transfer sizes when the DirWatcher supports
+ - tracking modificatons to files. -}
+watchesTransferSize :: Bool
+watchesTransferSize = modifyTracked
+
 {- Called when a transfer information file is removed. -}
 onDel :: Handler
 onDel st dstatus transferqueue file _ = case parseTransferFile file of
diff --git a/Assistant/Threads/Watcher.hs b/Assistant/Threads/Watcher.hs
index fa8b7b379..41396a23c 100644
--- a/Assistant/Threads/Watcher.hs
+++ b/Assistant/Threads/Watcher.hs
@@ -67,7 +67,7 @@ watchThread st dstatus transferqueue changechan = NamedThread thisThread $ do
 	where
 		startup = startupScan st dstatus
 		hook delay a = Just $ runHandler thisThread delay st dstatus transferqueue changechan a
-		hooks delayadd = WatchHooks
+		hooks delayadd = mkWatchHooks
 			{ addHook = hook (Seconds <$> delayadd) onAdd
 			, delHook = hook Nothing onDel
 			, addSymlinkHook = hook Nothing onAddSymlink