implemented servePutOffset and clientPutOffset

But, it's buggy: the server hangs without processing the VALIDITY,
and I can't seem to work out why. As far as I can see, storefile
is getting as far as running the validitycheck, which is supposed to
read that, but never does.

This is especially strange because what seems like the same protocol
doesn't hang when servePut runs it. This made me think that it needed
to use inAnnexWorker to be more like servePut, but that didn't help.

Another small problem with this is that it does create an empty
.git/annex/tmp/ file for the key. Since this will usually be used in
combination with servePut, that doesn't seem worth worrying about much.

P2P/Http.hs

@@ -720,6 +720,8 @@ type PutOffsetAPI result
 	= KeyParam
 	:> CU Required
 	:> BypassUUIDs
+	:> IsSecure
+	:> AuthHeader
 	:> Post '[JSON] result
 
 servePutOffset
@@ -731,29 +733,50 @@ servePutOffset
 	-> B64Key
 	-> B64UUID ClientSide
 	-> [B64UUID Bypass]
+	-> IsSecure
+	-> Maybe Auth
 	-> Handler t
-servePutOffset st resultmangle su apiver (B64Key k) cu bypass = undefined
-
+servePutOffset st resultmangle su apiver (B64Key k) cu bypass sec auth = do
+	res <- withP2PConnection apiver st cu su bypass sec auth WriteAction
+		(\cst -> cst { connectionWaitVar = False }) $ \conn ->
+			liftIO $ proxyClientNetProto conn $ getPutOffset k af
+	case res of
+		Right offset -> return $ resultmangle $
+			PutOffsetResultPlus (Offset offset)
+		Left plusuuids -> return $ resultmangle $
+			PutOffsetResultAlreadyHavePlus (map B64UUID plusuuids)
+  where
+	af = AssociatedFile Nothing
 
 clientPutOffset
-	:: B64UUID ServerSide
+	:: ClientEnv
 	-> ProtocolVersion
 	-> B64Key
+	-> B64UUID ServerSide
 	-> B64UUID ClientSide
 	-> [B64UUID Bypass]
-	-> ClientM PutOffsetResultPlus
-clientPutOffset su (ProtocolVersion ver) = case ver of
-	3 -> v3 su V3
-	2 -> v2 su V2
-	_ -> error "unsupported protocol version"
+	-> Maybe Auth
+	-> IO PutOffsetResultPlus
+clientPutOffset clientenv (ProtocolVersion ver) k su cu bypass auth
+	| ver == 0 = return (PutOffsetResultPlus (Offset 0))
+	| otherwise = 
+		withClientM cli clientenv $ \case
+			Left err -> throwM err
+			Right res -> return res
   where
+	cli = case ver of
+		3 -> v3 su V3 k cu bypass auth
+		2 -> v2 su V2 k cu bypass auth
+		1 -> plus <$> v1 su V1 k cu bypass auth
+		_ -> error "unsupported protocol version"
+	
 	_ :<|> _ :<|> _ :<|> _ :<|>
 		_ :<|> _ :<|> _ :<|> _ :<|>
 		_ :<|> _ :<|> _ :<|> _ :<|>
 		_ :<|>
 		_ :<|>
 		_ :<|> _ :<|> _ :<|> _ :<|>
-		v3 :<|> v2 :<|> _ = client p2pHttpAPI
+		v3 :<|> v2 :<|> v1 :<|> _ = client p2pHttpAPI
 
 type LockContentAPI
 	= KeyParam