unlock: Made atomic.

Command/Unlock.hs

@@ -44,11 +44,15 @@ perform dest key = do
 
 	g <- Annex.gitRepo
 	let src = gitAnnexLocation g key
-	liftIO $ removeFile dest
+	let tmpdest = gitAnnexTmpLocation g key
+	liftIO $ createDirectoryIfMissing True (parentDir tmpdest)
 	showNote "copying..."
-	ok <- liftIO $ copyFile src dest
+	ok <- liftIO $ copyFile src tmpdest
         if ok
                 then do
-			liftIO $ allowWrite dest
+			liftIO $ do
+				removeFile dest
+				renameFile tmpdest dest
+				allowWrite dest
 			next $ return True
                 else error "copy failed!"

debian/changelog

@@ -6,6 +6,7 @@ git-annex (0.20110611) UNRELEASED; urgency=low
     such as btrfs.
   * Allow --trust etc to specify a repository by name, for temporarily 
     trusting repositories that are not configured remotes.
+  * unlock: Made atomic.
   * git-union-merge: New git subcommand, that does a generic union merge
     operation, and operates efficiently without touching the working tree.
 

doc/bugs/git_annex_unlock_is_not_atomic.mdwn

@@ -3,3 +3,5 @@ Running a command like
 git annex unlock myfile
 
 is not atomic, that is if the execution is aborted you may end up with an incomplete version of myfile in the directory. If you don't notice this you may lock it again and then propagate this bad version of the file to your other repositories. A simple workaround is to simply name it something else while unlocking and then rename it to the correct filename once it's completely copied. I don't know Haskel yet so I can not fix this issue otherwise I would sure try. A part from this, I love git annex.
+
+> [[fixed|done]] --[[Joey]]