unannex: New, much slower, but more safe behavior

Copies files out of the annex. This avoids an unannex of one file breaking
other files that link to the same content. Also, it means that the content
remains in the annex using up space until cleaned up with  "git annex
unused".

(The behavior of unannex --fast has not changed; it still hard
links to content in the annex. --fast was not made the default because it
is potentially unsafe; editing such a hard linked file can unexpectedly
change content stored in the annex.)

Command/Unannex.hs

@@ -13,11 +13,11 @@ import Common.Annex
 import Command
 import Config
 import qualified Annex
-import Logs.Location
 import Annex.Content
 import Annex.Content.Direct
 import qualified Git.Command
 import qualified Git.LsFiles as LsFiles
+import Utility.CopyFile
 
 def :: [Command]
 def = [command "unannex" paramPaths seek SectionUtility
@@ -60,28 +60,24 @@ performIndirect file key = do
 
 cleanupIndirect :: FilePath -> Key -> CommandCleanup
 cleanupIndirect file key = do
+	src <- calcRepo $ gitAnnexLocation key
 	ifM (Annex.getState Annex.fast)
-		( goFast
-		, go
+		( hardlinkfrom src
+		, copyfrom src
 		)
-	return True
   where
-#ifdef mingw32_HOST_OS
-	goFast = go
-#else
-	goFast = do
-		-- fast mode: hard link to content in annex
-		src <- calcRepo $ gitAnnexLocation key
-		-- creating a hard link could fall; fall back to non fast mode
+	copyfrom src = 
+		thawContent file `after` liftIO (copyFileExternal src file)
+	hardlinkfrom src =
+#ifndef mingw32_HOST_OS
+		-- creating a hard link could fall; fall back to copying
 		ifM (liftIO $ catchBoolIO $ createLink src file >> return True)
-			( thawContent file
-			, go
+			( return True
+			, copyfrom src
 			)
+#else
+		copyfrom src
 #endif
-	go = do
-		fromAnnex key file
-		logStatus key InfoMissing
-
 
 performDirect :: FilePath -> Key -> CommandPerform
 performDirect file key = do

Command/Uninit.hs

@@ -38,7 +38,7 @@ check = do
 seek :: [CommandSeek]
 seek = 
 	[ withFilesNotInGit $ whenAnnexed startCheckIncomplete
-	, withFilesInGit $ whenAnnexed startUnannex
+	, withFilesInGit $ whenAnnexed Command.Unannex.start
 	, withNothing start
 	]
 
@@ -51,14 +51,6 @@ startCheckIncomplete file _ = error $ unlines
 	, "Not continuing with uninit; either delete or git annex add the file and retry."
 	]
 
-startUnannex :: FilePath -> (Key, Backend) -> CommandStart
-startUnannex file info = do
-	-- Force fast mode before running unannex. This way, if multiple
-	-- files link to a key, it will be left in the annex and hardlinked
-	-- to by each.
-	Annex.changeState $ \s -> s { Annex.fast = True }
-	Command.Unannex.start file info
-
 start :: CommandStart
 start = next $ next $ do
 	annexdir <- fromRepo gitAnnexDir