unify exception handling into Utility.Exception

Removed old extensible-exceptions, only needed for very old ghc.

Made webdav use Utility.Exception, to work after some changes in DAV's
exception handling.

Removed Annex.Exception. Mostly this was trivial, but note that
tryAnnex is replaced with tryNonAsync and catchAnnex replaced with
catchNonAsync. In theory that could be a behavior change, since the former
caught all exceptions, and the latter don't catch async exceptions.

However, in practice, nothing in the Annex monad uses async exceptions.
Grepping for throwTo and killThread only find stuff in the assistant,
which does not seem related.

Command.Add.undo is changed to accept a SomeException, and things
that use it for rollback now catch non-async exceptions, rather than
only IOExceptions.

Command/Add.hs

@@ -10,7 +10,6 @@
 module Command.Add where
 
 import Common.Annex
-import Annex.Exception
 import Command
 import Types.KeySource
 import Backend
@@ -33,6 +32,8 @@ import Annex.FileMatcher
 import Annex.ReplaceFile
 import Utility.Tmp
 
+import Control.Exception (IOException)
+
 def :: [Command]
 def = [notBareRepo $ withOptions [includeDotFilesOption] $
 	command "add" paramPaths seek SectionCommon
@@ -103,7 +104,7 @@ lockDown = either (\e -> showErr e >> return Nothing) (return . Just) <=< lockDo
 lockDown' :: FilePath -> Annex (Either IOException KeySource)
 lockDown' file = ifM crippledFileSystem
 	( withTSDelta $ liftIO . tryIO . nohardlink
-	, tryAnnexIO $ do
+	, tryIO $ do
 		tmp <- fromRepo gitAnnexTmpMiscDir
 		createAnnexDirectory tmp
 		go tmp
@@ -167,7 +168,7 @@ ingest (Just source) = withTSDelta $ \delta -> do
 		)
 
 	goindirect (Just (key, _)) mcache ms = do
-		catchAnnex (moveAnnex key $ contentLocation source)
+		catchNonAsync (moveAnnex key $ contentLocation source)
 			(undo (keyFilename source) key)
 		maybe noop (genMetaData key (keyFilename source)) ms
 		liftIO $ nukeFile $ keyFilename source
@@ -206,23 +207,23 @@ perform file = lockDown file >>= ingest >>= go
 
 {- On error, put the file back so it doesn't seem to have vanished.
  - This can be called before or after the symlink is in place. -}
-undo :: FilePath -> Key -> IOException -> Annex a
+undo :: FilePath -> Key -> SomeException -> Annex a
 undo file key e = do
 	whenM (inAnnex key) $ do
 		liftIO $ nukeFile file
-		catchAnnex (fromAnnex key file) tryharder
+		catchNonAsync (fromAnnex key file) tryharder
 		logStatus key InfoMissing
-	throwAnnex e
+	throwM e
   where
 	-- fromAnnex could fail if the file ownership is weird
-	tryharder :: IOException -> Annex ()
+	tryharder :: SomeException -> Annex ()
 	tryharder _ = do
 		src <- calcRepo $ gitAnnexLocation key
 		liftIO $ moveFile src file
 
 {- Creates the symlink to the annexed content, returns the link target. -}
 link :: FilePath -> Key -> Maybe InodeCache -> Annex String
-link file key mcache = flip catchAnnex (undo file key) $ do
+link file key mcache = flip catchNonAsync (undo file key) $ do
 	l <- inRepo $ gitAnnexLink file key
 	replaceFile file $ makeAnnexLink l
 

Command/Direct.hs

@@ -7,8 +7,6 @@
 
 module Command.Direct where
 
-import Control.Exception.Extensible
-
 import Common.Annex
 import Command
 import qualified Git
@@ -16,7 +14,6 @@ import qualified Git.LsFiles
 import qualified Git.Branch
 import Config
 import Annex.Direct
-import Annex.Exception
 
 def :: [Command]
 def = [notBareRepo $ noDaemonRunning $
@@ -52,7 +49,7 @@ perform = do
 			Nothing -> noop
 			Just a -> do
 				showStart "direct" f
-				r' <- tryAnnex a
+				r' <- tryNonAsync a
 				case r' of
 					Left e -> warnlocked e
 					Right _ -> showEndOk

Command/FuzzTest.hs

@@ -13,7 +13,6 @@ import Command
 import qualified Git.Config
 import Config
 import Utility.ThreadScheduler
-import Annex.Exception
 import Utility.DiskFree
 
 import Data.Time.Clock
@@ -56,7 +55,7 @@ fuzz :: Handle -> Annex ()
 fuzz logh = do
 	action <- genFuzzAction
 	record logh $ flip Started action
-	result <- tryAnnex $ runFuzzAction action
+	result <- tryNonAsync $ runFuzzAction action
 	record logh $ flip Finished $
 		either (const False) (const True) result
 

Command/Indirect.hs

@@ -7,8 +7,6 @@
 
 module Command.Indirect where
 
-import Control.Exception.Extensible
-
 import Common.Annex
 import Command
 import qualified Git
@@ -21,7 +19,6 @@ import Annex.Direct
 import Annex.Content
 import Annex.Content.Direct
 import Annex.CatFile
-import Annex.Exception
 import Annex.Init
 import qualified Command.Add
 
@@ -88,12 +85,12 @@ perform = do
 		removeInodeCache k
 		removeAssociatedFiles k
 		whenM (liftIO $ not . isSymbolicLink <$> getSymbolicLinkStatus f) $ do
-			v <-tryAnnexIO (moveAnnex k f)
+			v <- tryNonAsync (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)
+				Left e -> catchNonAsync (Command.Add.undo f k e)
 					warnlocked
 		showEndOk
 

Command/Map.hs

@@ -7,7 +7,6 @@
 
 module Command.Map where
 
-import Control.Exception.Extensible
 import qualified Data.Map as M
 
 import Common.Annex
@@ -247,7 +246,7 @@ combineSame = map snd . nubBy sameuuid . map pair
 
 safely :: IO Git.Repo -> IO (Maybe Git.Repo)
 safely a = do
-	result <- try a :: IO (Either SomeException Git.Repo)
+	result <- tryNonAsync a
 	case result of
 		Left _ -> return Nothing
 		Right r' -> return $ Just r'

Command/Move.hs

@@ -152,17 +152,17 @@ fromOk src key = go =<< Annex.getState Annex.force
 fromPerform :: Remote -> Bool -> Key -> AssociatedFile -> CommandPerform
 fromPerform src move key afile = moveLock move key $
 	ifM (inAnnex key)
-		( handle move True
-		, handle move =<< go
+		( dispatch move True
+		, dispatch move =<< go
 		)
   where
 	go = notifyTransfer Download afile $ 
 		download (Remote.uuid src) key afile noRetry $ \p -> do
 			showAction $ "from " ++ Remote.name src
 			getViaTmp key $ \t -> Remote.retrieveKeyFile src key afile t p
-	handle _ False = stop -- failed
-	handle False True = next $ return True -- copy complete
-	handle True True = do -- finish moving
+	dispatch _ False = stop -- failed
+	dispatch False True = next $ return True -- copy complete
+	dispatch True True = do -- finish moving
 		ok <- Remote.removeKey src key
 		next $ Command.Drop.cleanupRemote key src ok
 

Command/PreCommit.hs

@@ -19,7 +19,6 @@ import Annex.Hook
 import Annex.View
 import Annex.View.ViewedFile
 import Annex.Perms
-import Annex.Exception
 import Logs.View
 import Logs.MetaData
 import Types.View

Command/TestRemote.hs

@@ -31,7 +31,6 @@ import Locations
 import Test.Tasty
 import Test.Tasty.Runners
 import Test.Tasty.HUnit
-import Control.Exception
 import "crypto-api" Crypto.Random
 import qualified Data.ByteString as B
 import qualified Data.ByteString.Lazy as L

Command/Vicfg.hs

@@ -217,7 +217,7 @@ parseCfg curcfg = go [] curcfg . lines
 		| null l = Right cfg
 		| "#" `isPrefixOf` l = Right cfg
 		| null setting || null f = Left "missing field"
-		| otherwise = handle cfg f setting value'
+		| otherwise = parsed cfg f setting value'
 	  where
 		(setting, rest) = separate isSpace l
 		(r, value) = separate (== '=') rest
@@ -225,7 +225,7 @@ parseCfg curcfg = go [] curcfg . lines
 		f = reverse $ trimspace $ reverse $ trimspace r
 		trimspace = dropWhile isSpace
 
-	handle cfg f setting value
+	parsed cfg f setting value
 		| setting == "trust" = case readTrustLevel value of
 			Nothing -> badval "trust value" value
 			Just t ->