, cReader ∷ !ThreadId
}
-data Phase = Initial
- | WroteContinue
- | WroteHeader
- deriving (Eq, Ord, Show)
-
responseWriter ∷ HandleLike h ⇒ Config → h → InteractionQueue → ThreadId → IO ()
responseWriter cnf h tQueue readerTID
= awaitSomethingToWrite (Context cnf h tQueue readerTID)
awaitSomethingToWrite ctx@(Context {..})
= join $
atomically $
- -- キューが空でなくなるまで待つ
do queue ← readTVar cQueue
case S.viewr queue of
EmptyR → retry
queue' :> itr → do writeTVar cQueue queue'
- return $ awaitSomethingToWriteOn ctx itr Initial
-
--- GettingBody 状態にあり、Continue が期待されてゐて、それがまだ送信前
--- なのであれば、Continue を送信する。
-awaitSomethingToWriteOn ∷ HandleLike h
- ⇒ Context h
- → Interaction
- → Phase
- → IO ()
-awaitSomethingToWriteOn ctx itr phase
- = join $
- atomically $
- do state ← readTVar $ itrState itr
- if state ≡ ReceivingBody then
- writeContinueIfNeeded ctx itr phase
- else
- if state ≥ SendingBody then
- writeHeaderOrBodyIfNeeded ctx itr phase
- else
- retry
+ return $ writeContinueIfNeeded ctx itr
writeContinueIfNeeded ∷ HandleLike h
⇒ Context h
→ Interaction
- → Phase
- → STM (IO ())
-writeContinueIfNeeded ctx itr@(Interaction {..}) phase
- | phase ≡ Initial ∧ itrExpectedContinue ≡ Just True
- = do isRequested ← isEmptyTMVar itrReceiveBodyReq
- if isRequested then
- return $ writeContinue ctx itr
- else
- retry
- | otherwise
- = retry
-
--- DecidingBody 以降の状態にあり、まだヘッダを出力する前であれば、ヘッ
--- ダを出力する。ヘッダ出力後であり、bodyToSend が空でなければ、それを
--- 出力する。空である時は、もし状態がDone であれば後処理をする。
-writeHeaderOrBodyIfNeeded ∷ HandleLike h
- ⇒ Context h
- → Interaction
- → Phase
- → STM (IO ())
-writeHeaderOrBodyIfNeeded ctx itr@(Interaction {..}) phase
- | phase < WroteHeader
- = return $ writeHeader ctx itr
- | otherwise
- = do noBodyToWrite ← isEmptyTMVar itrBodyToSend
- if noBodyToWrite then
- do state ← readTVar itrState
- if state ≡ Done then
- return $ finalize ctx itr
- else
- retry
- else
- return $ writeBodyChunk ctx itr phase
-
-writeContinue ∷ HandleLike h ⇒ Context h → Interaction → IO ()
-writeContinue ctx@(Context {..}) itr@(Interaction {..})
- = do let cont = Response {
- resVersion = HttpVersion 1 1
- , resStatus = Continue
- , resHeaders = (∅)
- }
- cont' ← completeUnconditionalHeaders cConfig cont
- hPutBuilder cHandle $ A.toBuilder $ printResponse cont'
- hFlush cHandle
- awaitSomethingToWriteOn ctx itr WroteContinue
+ → IO ()
+writeContinueIfNeeded ctx@(Context {..}) itr@(Interaction {..})
+ = do isNeeded ← atomically $ readTMVar itrSendContinue
+ when isNeeded
+ $ do let cont = Response {
+ resVersion = HttpVersion 1 1
+ , resStatus = Continue
+ , resHeaders = (∅)
+ }
+ cont' ← completeUnconditionalHeaders cConfig cont
+ hPutBuilder cHandle $ A.toBuilder $ printResponse cont'
+ hFlush cHandle
+ writeHeader ctx itr
writeHeader ∷ HandleLike h
⇒ Context h
→ Interaction
→ IO ()
writeHeader ctx@(Context {..}) itr@(Interaction {..})
- = do res ← atomically $ readTVar itrResponse
+ = do res ← atomically $
+ do state ← readTVar itrState
+ if state ≥ SendingBody then
+ readTVar itrResponse
+ else
+ retry -- Too early to write header fields.
hPutBuilder cHandle $ A.toBuilder $ printResponse res
hFlush cHandle
- awaitSomethingToWriteOn ctx itr WroteHeader
+ writeBodyIfNeeded ctx itr
-writeBodyChunk ∷ HandleLike h
- ⇒ Context h
- → Interaction
- → Phase
- → IO ()
-writeBodyChunk ctx@(Context {..}) itr@(Interaction {..}) phase
+writeBodyIfNeeded ∷ HandleLike h
+ ⇒ Context h
+ → Interaction
+ → IO ()
+writeBodyIfNeeded ctx itr@(Interaction {..})
= join $
atomically $
do willDiscardBody ← readTVar itrWillDiscardBody
if willDiscardBody then
- do _ ← tryTakeTMVar itrBodyToSend
- return $ awaitSomethingToWriteOn ctx itr phase
+ return $ discardBody ctx itr
else
do willChunkBody ← readTVar itrWillChunkBody
- chunk ← takeTMVar itrBodyToSend
- return $
- do if willChunkBody then
- hPutBuilder cHandle $ BB.chunkedTransferEncoding chunk
- else
- hPutBuilder cHandle chunk
- hFlush cHandle
- awaitSomethingToWriteOn ctx itr phase
+ if willChunkBody then
+ return $ writeChunkedBody ctx itr
+ else
+ return $ writeNonChunkedBody ctx itr
-finishBodyChunk ∷ HandleLike h ⇒ Context h → Interaction → IO ()
-finishBodyChunk (Context {..}) (Interaction {..})
+discardBody ∷ HandleLike h
+ ⇒ Context h
+ → Interaction
+ → IO ()
+discardBody ctx itr@(Interaction {..})
= join $
atomically $
- do willDiscardBody ← readTVar itrWillDiscardBody
- willChunkBody ← readTVar itrWillChunkBody
- if ((¬) willDiscardBody) ∧ willChunkBody then
- return $
- do hPutBuilder cHandle BB.chunkedTransferTerminator
- hFlush cHandle
- else
- return $ return ()
+ do chunk ← tryTakeTMVar itrBodyToSend
+ case chunk of
+ Just _ → return $ discardBody ctx itr
+ Nothing → do state ← readTVar itrState
+ if state ≡ Done then
+ return $ finalize ctx itr
+ else
+ retry
+
+writeChunkedBody ∷ HandleLike h
+ ⇒ Context h
+ → Interaction
+ → IO ()
+writeChunkedBody ctx@(Context {..}) itr@(Interaction {..})
+ = join $
+ atomically $
+ do chunk ← tryTakeTMVar itrBodyToSend
+ case chunk of
+ Just b → return $
+ do hPutBuilder cHandle $ BB.chunkedTransferEncoding b
+ hFlush cHandle
+ writeChunkedBody ctx itr
+ Nothing → do state ← readTVar itrState
+ if state ≡ Done then
+ return $ finalize ctx itr
+ else
+ retry
+
+writeNonChunkedBody ∷ HandleLike h
+ ⇒ Context h
+ → Interaction
+ → IO ()
+writeNonChunkedBody ctx@(Context {..}) itr@(Interaction {..})
+ = join $
+ atomically $
+ do chunk ← tryTakeTMVar itrBodyToSend
+ case chunk of
+ Just b → return $
+ do hPutBuilder cHandle b
+ hFlush cHandle
+ writeNonChunkedBody ctx itr
+ Nothing → do state ← readTVar itrState
+ if state ≡ Done then
+ return $ finalize ctx itr
+ else
+ retry
finalize ∷ HandleLike h ⇒ Context h → Interaction → IO ()
-finalize ctx@(Context {..}) itr@(Interaction {..})
- = do finishBodyChunk ctx itr
- willClose ← atomically $
- do queue ← readTVar cQueue
- case S.viewr queue of
- EmptyR → return () -- this should never happen
- remaining :> _ → writeTVar cQueue remaining
- readTVar itrWillClose
- if willClose then
- -- reader は恐らく hWaitForInput してゐる最中なので、スレッ
- -- ドを豫め殺して置かないとをかしくなる。
- do killThread cReader
- hClose cHandle
- else
- awaitSomethingToWrite ctx
+finalize ctx@(Context {..}) (Interaction {..})
+ = join $
+ atomically $
+ do sentContinue ← takeTMVar itrSendContinue
+ willDiscardBody ← readTVar itrWillDiscardBody
+ willChunkBody ← readTVar itrWillChunkBody
+ willClose ← readTVar itrWillClose
+ queue ← readTVar cQueue
+ case S.viewr queue of
+ queue' :> _
+ → writeTVar cQueue queue'
+ EmptyR
+ → fail "finalize: cQueue is empty, which should never happen."
+ return $
+ do when (((¬) willDiscardBody) ∧ willChunkBody)
+ $ do hPutBuilder cHandle BB.chunkedTransferTerminator
+ hFlush cHandle
+ if willClose ∨ needToClose sentContinue then
+ -- The RequestReader is probably blocking on
+ -- hWaitForInput so we have to kill it before
+ -- closing the socket.
+ -- THINKME: Couldn't that somehow be avoided?
+ do killThread cReader
+ hClose cHandle
+ else
+ awaitSomethingToWrite ctx
+ where
+ needToClose ∷ Bool → Bool
+ needToClose sentContinue
+ -- We've sent both "HTTP/1.1 100 Continue" and a final
+ -- response, so nothing prevents our connection from keeping
+ -- alive.
+ | sentContinue = False
+ -- We've got "Expect: 100-continue" but have sent a final
+ -- response without sending "HTTP/1.1 100
+ -- Continue". According to the RFC 2616 (HTTP/1.1), it is
+ -- undecidable whether the client will send us its
+ -- (rejected) request body OR start a completely new request
+ -- in this situation. So the only possible thing to do is to
+ -- brutally shutdown the connection.
+ | itrExpectedContinue ≡ Just True = True
+ -- The client didn't expect 100-continue so we haven't sent
+ -- one. No need to do anything special.
+ | otherwise = False
projects / Lucu.git / blobdiff