indirect: Better behavior when a file in direct mode is not owned by the user running the conversion.

Annex/Exception.hs

@@ -13,6 +13,7 @@
 module Annex.Exception (
 	bracketIO,
 	tryAnnex,
+	tryAnnexIO,
 	throwAnnex,
 	catchAnnex,
 ) where
@@ -30,6 +31,10 @@ bracketIO setup cleanup = M.bracket (liftIO setup) (liftIO . cleanup)
 tryAnnex :: Annex a -> Annex (Either SomeException a)
 tryAnnex = M.try
 
+{- try in the Annex monad, but only catching IO exceptions -}
+tryAnnexIO :: Annex a -> Annex (Either IOException a)
+tryAnnexIO = M.try
+
 {- throw in the Annex monad -}
 throwAnnex :: Exception e => e -> Annex a
 throwAnnex = M.throw

Command/Indirect.hs

@@ -8,6 +8,7 @@
 module Command.Indirect where
 
 import System.PosixCompat.Files
+import Control.Exception.Extensible
 
 import Common.Annex
 import Command
@@ -22,7 +23,9 @@ import Annex.Content
 import Annex.CatFile
 import Annex.Version
 import Annex.Perms
+import Annex.Exception
 import Init
+import qualified Command.Add
 
 def :: [Command]
 def = [notBareRepo $ noDaemonRunning $
@@ -87,15 +90,24 @@ perform = do
 		thawContentDir =<< calcRepo (gitAnnexLocation k)
 		cleandirect k -- clean before content directory gets frozen
 		whenM (liftIO $ not . isSymbolicLink <$> getSymbolicLinkStatus f) $ do
-			moveAnnex k f
-			l <- inRepo $ gitAnnexLink f k
-			liftIO $ createSymbolicLink l f
+			v <-tryAnnexIO (moveAnnex k f)
+			case v of
+				Right _ -> do 
+					l <- inRepo $ gitAnnexLink f k
+					liftIO $ createSymbolicLink l f
+				Left e -> catchAnnex (Command.Add.undo f k e)
+					warnlocked
 		showEndOk
 
+ 	warnlocked :: SomeException -> Annex ()
+	warnlocked e = do
+		warning $ show e
+		warning "leaving this file as-is; correct this problem and run git annex add on it"
+
 	cleandirect k = do
 		liftIO . nukeFile =<< calcRepo (gitAnnexInodeCache k)
 		liftIO . nukeFile =<< calcRepo (gitAnnexMapping k)
-
+	
 cleanup :: CommandCleanup
 cleanup = do
 	setVersion defaultVersion

debian/changelog

@@ -13,6 +13,8 @@ git-annex (4.20130921) UNRELEASED; urgency=low
   * assistant: Clear the list of failed transfers when doing a full transfer
     scan. This prevents repeated retries to download files that are not
     available, or are not referenced by the current git tree.
+  * indirect: Better behavior when a file in direct mode is not owned by
+    the user running the conversion.
 
  -- Joey Hess <joeyh@debian.org>  Sun, 22 Sep 2013 19:42:29 -0400
 

doc/bugs/git_annex_indirect_can_fail_catastrophically.mdwn

@@ -69,3 +69,10 @@ index 7835988..ed8ea6c 100644
 """]]
 
 Any update on this? Why is `-a` used here? -- [[anarcat]]
+
+> -a is not really the problem. You certianly do usually want
+> to commit your changes before converting to direct mode.
+> 
+> [[done]]; now when this happens it catches the exception and 
+> leaves the file in direct mode, which is the same as it being
+> unlocked. --[[Joey]]