fix process and FD leak

Fix process and file descriptor leak that was exposed when git-annex was
built with ghc 8.2.1. Apparently ghc has changed its behavior of GC
of open file handles that are pipes to running processes. That
broke git-annex test on OSX due to running out of FDs.

Audited for all uses of Annex.new and made stopCoProcesses be called
once it's done with the state. Fixed several places that might have
leaked in other situations than running the test suite.

This commit was sponsored by Ewen McNeill.

3 files changed, 17 insertions, 14 deletions

diff --git a/Annex/Action.hs b/Annex/Action.hs
index a18ebaf78..fc8be6c91 100644
--- a/Annex/Action.hs
+++ b/Annex/Action.hs
@@ -17,6 +17,10 @@ import System.Posix.Signals
 import Annex.Common
 import qualified Annex
 import Annex.Content
+import Annex.CatFile
+import Annex.CheckAttr
+import Annex.HashObject
+import Annex.CheckIgnore
 
 {- Actions to perform each time ran. -}
 startup :: Annex ()
@@ -32,4 +36,13 @@ shutdown :: Bool -> Annex ()
 shutdown nocommit = do
 	saveState nocommit
 	sequence_ =<< M.elems <$> Annex.getState Annex.cleanup
+	stopCoProcesses
 	liftIO reapZombies -- zombies from long-running git processes
+
+{- Stops all long-running git query processes. -}
+stopCoProcesses :: Annex ()
+stopCoProcesses = do
+	catFileStop
+	checkAttrStop
+	hashObjectStop
+	checkIgnoreStop
diff --git a/Annex/Concurrent.hs b/Annex/Concurrent.hs
index 71a70fa5b..65acb0450 100644
--- a/Annex/Concurrent.hs
+++ b/Annex/Concurrent.hs
@@ -7,12 +7,9 @@
 
 module Annex.Concurrent where
 
-import Annex.Common
 import Annex
-import Annex.CatFile
-import Annex.CheckAttr
-import Annex.HashObject
-import Annex.CheckIgnore
+import Annex.Common
+import Annex.Action
 import qualified Annex.Queue
 
 import qualified Data.Map as M
@@ -61,11 +58,3 @@ mergeState st = do
 		uncurry addCleanup
 	Annex.Queue.mergeFrom st'
 	changeState $ \s -> s { errcounter = errcounter s + errcounter st' }
-
-{- Stops all long-running git query processes. -}
-stopCoProcesses :: Annex ()
-stopCoProcesses = do
-	catFileStop
-	checkAttrStop
-	hashObjectStop
-	checkIgnoreStop
diff --git a/Annex/MakeRepo.hs b/Annex/MakeRepo.hs
index adf49ed2c..e03196664 100644
--- a/Annex/MakeRepo.hs
+++ b/Annex/MakeRepo.hs
@@ -16,6 +16,7 @@ import qualified Git.Branch
 import qualified Annex
 import Annex.UUID
 import Annex.Direct
+import Annex.Action
 import Types.StandardGroups
 import Logs.PreferredContent
 import qualified Annex.Branch
@@ -42,7 +43,7 @@ makeRepo path bare = ifM (probeRepoExists path)
 inDir :: FilePath -> Annex a -> IO a
 inDir dir a = do
 	state <- Annex.new =<< Git.Config.read =<< Git.Construct.fromPath dir
-	Annex.eval state a
+	Annex.eval state $ a `finally` stopCoProcesses
 
 {- Creates a new repository, and returns its UUID. -}
 initRepo :: Bool -> Bool -> FilePath -> Maybe String -> Maybe StandardGroup -> IO UUID