uninit, unannex --fast: If hard link creation fails, fall back to slow mode.

Command/Unannex.hs

@@ -49,14 +49,20 @@ cleanup file key = do
 	void $ liftIO clean
 
 	ifM (Annex.getState Annex.fast)
-		( do
+		( goFast
-			-- fast mode: hard link to content in annex
+		, go
-			src <- inRepo $ gitAnnexLocation key
-			liftIO $ createLink src file
-			thawContent file
-		, do
-			fromAnnex key file
-			logStatus key InfoMissing
 		)
 
 	return True
+  where
+	goFast = do
+		-- fast mode: hard link to content in annex
+		src <- inRepo $ gitAnnexLocation key
+		-- creating a hard link could fall; fall back to non fast mode
+		ifM (liftIO $ catchBoolIO $ createLink src file >> return True)
+			( thawContent file
+			, go
+			)
+	go = do
+		fromAnnex key file
+		logStatus key InfoMissing

debian/changelog

@@ -11,6 +11,8 @@ git-annex (3.20130125) UNRELEASED; urgency=low
   * assistant: Fix location log when adding new file in direct mode.
   * Deal with stale mappings for deleted file in direct mode.
   * pre-commit: Update direct mode mappings. 
+  * uninit, unannex --fast: If hard link creation fails, fall back to slow
+    mode.
 
  -- Joey Hess <joeyh@debian.org>  Sat, 26 Jan 2013 15:48:40 +1100
 

doc/bugs/uninit_does_not_abort_when_hard_link_creation_fails.mdwn

@@ -39,3 +39,9 @@ Issue the following commands on a file system where hard links are disabled:
 git-annex should probably not be used on a file system where hard links are disabled.
 
 However, if the user is not aware that he's using git-annex on such a filesystem, he will accidently delete his annexed files by issuing a `git annex uninit` command.
+
+> git-annex needs a POSIX filesystem, which includes the ability to create
+> hard links. The `git annex add` in the example above will fail
+> trying to create a hard link with current versions.
+> 
+> I've made uninit fall back to a non-hard link mode. [[done]] --[[Joey]]