convert to withCreateProcess for async exception safety

This handles all createProcessSuccess callers, and aside from process
pools, the complete conversion of all process running to async exception
safety should be complete now.

Also, was able to remove from Utility.Process the old API that I now
know was not a good idea. And proof it was bad: The code size went *down*,
despite there being a fair bit of boilerplate for some future API to
reduce.

Remote/Ddar.hs

@@ -1,11 +1,13 @@
 {- Using ddar as a remote. Based on bup and rsync remotes.
  -
- - Copyright 2011 Joey Hess <id@joeyh.name>
+ - Copyright 2011-2020 Joey Hess <id@joeyh.name>
  - Copyright 2014 Robie Basak <robie@justgohome.co.uk>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
+{-# LANGUAGE BangPatterns #-}
+
 module Remote.Ddar (remote) where
 
 import qualified Data.Map as M
@@ -201,12 +203,18 @@ ddarDirectoryExists ddarrepo
 inDdarManifest :: DdarRepo -> Key -> Annex (Either String Bool)
 inDdarManifest ddarrepo k = do
 	(cmd, params) <- ddarRemoteCall NoConsumeStdin ddarrepo 't' []
-	let p = proc cmd $ toCommand params
-	liftIO $ catchMsgIO $ withHandle StdoutHandle createProcessSuccess p $ \h -> do
-		contents <- hGetContents h
-		return $ elem k' $ lines contents
+	let p = (proc cmd $ toCommand params)
+		{ std_out = CreatePipe }
+	liftIO $ catchMsgIO $ withCreateProcess p (go p)
   where
 	k' = serializeKey k
+	
+	go p _ (Just hout) _ pid = do
+		contents <- hGetContents hout
+		let !r = elem k' (lines contents)
+		forceSuccessProcess p pid
+		return r
+	go _ _ _ _ _ = error "internal"
 
 checkKey :: DdarRepo -> CheckPresent
 checkKey ddarrepo key = do