Windows: Fix hang when adding several files at once.

Utility/CoProcess.hs

@@ -43,7 +43,7 @@ start restartable cmd params env = do
 
 start' :: CoProcessSpec -> IO CoProcessState
 start' s = do
-	(to, from, _err, pid) <- runInteractiveProcess (coProcessCmd s) (coProcessParams s) Nothing (coProcessEnv s)
+	(pid, to, from) <- startInteractiveProcess (coProcessCmd s) (coProcessParams s) (coProcessEnv s)
 	return $ CoProcessState pid to from s
 
 stop :: CoProcessHandle -> IO ()

Utility/Process.hs

@@ -26,7 +26,7 @@ module Utility.Process (
 	withBothHandles,
 	withQuietOutput,
 	createProcess,
-	runInteractiveProcess,
+	startInteractiveProcess,
 	stdinHandle,
 	stdoutHandle,
 	stderrHandle,
@@ -34,7 +34,7 @@ module Utility.Process (
 
 import qualified System.Process
 import System.Process as X hiding (CreateProcess(..), createProcess, runInteractiveProcess, readProcess, readProcessWithExitCode, system, rawSystem, runInteractiveCommand, runProcess)
-import System.Process hiding (createProcess, runInteractiveProcess, readProcess)
+import System.Process hiding (createProcess, readProcess)
 import System.Exit
 import System.IO
 import System.Log.Logger
@@ -300,17 +300,19 @@ createProcess p = do
 	debugProcess p
 	System.Process.createProcess p
 
-runInteractiveProcess
-	:: FilePath	
-	-> [String]	
-	-> Maybe FilePath	
-	-> Maybe [(String, String)]	
-	-> IO (Handle, Handle, Handle, ProcessHandle)
-runInteractiveProcess f args c e = do
-	debugProcess $ (proc f args)
-			{ std_in = CreatePipe
-			, std_out = CreatePipe
-			, std_err = CreatePipe
-			, env = e
-			}
-	System.Process.runInteractiveProcess f args c e
+{- Starts an interactive process. Unlike runInteractiveProcess in
+ - System.Process, stderr is inherited. -}
+startInteractiveProcess
+	:: FilePath
+	-> [String]
+	-> Maybe [(String, String)]
+	-> IO (ProcessHandle, Handle, Handle)
+startInteractiveProcess cmd args environ = do
+	let p = (proc cmd args)
+		{ std_in = CreatePipe
+		, std_out = CreatePipe
+		, std_err = Inherit
+		, env = environ
+		}
+	(Just from, Just to, _, pid) <- createProcess p
+	return (pid, to, from)

debian/changelog

@@ -20,6 +20,7 @@ git-annex (4.20130602) UNRELEASED; urgency=low
     with git annex sync or by the assistant.
   * Android: Fix use of cp command to not try to use features present
     only on build system.
+  * Windows: Fix hang when adding several files at once.
 
  -- Joey Hess <joeyh@debian.org>  Mon, 10 Jun 2013 12:52:44 -0400
 

doc/bugs/windows_port_-_git_annex_add_hangs_when_adding_17_files_at_once_or_more_.mdwn

@@ -180,3 +180,18 @@ info"]
 
 # End of transcript or log.
 """]]
+
+> Reproduced this, and git update-index was in fact not hanging. 
+> Instead, after that was done, it tried to stop the git hash-object
+> process, and this hung. 
+> 
+> It seems that the use of runInteractiveProcess is at fault somehow,
+> and I guess it must be due to it opening a pipe for stderr, which
+> I don't need or want. Perhaps I need to ensure I read from that pipe,
+> or windows keeps the process from terminating. (Unix would just toss the piped
+> data away.)
+> 
+> That was the only place runInteractiveProcess was used, so I replaced
+> it with an alternative that lets stderr be inherited. With this change,
+> I have successfully added 1000 files to the annex in one go, with no
+> hang. Provisionally [[done]]. --[[Joey]]