wizard-wipeout/src-server/Server/Communication/Receive.hs
Amedeo Molnár 73adfff54c tidbits
2024-11-29 11:24:07 +01:00

74 lines
2.2 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
module Server.Communication.Receive where
import Control.Concurrent (threadDelay)
import qualified Control.Concurrent.STM as STM
import Control.Exception
import qualified Data.Aeson as A
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy.Char8 as B8
import Foreign.Marshal hiding (void)
import Network.Socket
import System.Random
-- internal imports
import Library.Types
import Server.Communication.Send
import Server.Log (logPrintIO)
import Server.Types
-- | receive a 'ClientMessage'
receiveMessage
:: LogLevel
-> STM.TMVar [ClientSocket]
-> STM.TMVar [ClientQueue]
-> STM.TMVar Socket
-> STM.TQueue ClientMessage
-> IO ()
receiveMessage curLevel socketList queueList sockContainer queue = do
randSleep <- randomRIO (1, 1000)
threadDelay randSleep
let maxBufferLength = 4096
sock <- STM.atomically $ STM.readTMVar sockContainer
logPrintIO curLevel Verbose "read socket container for receiving"
ptr <- mallocArray maxBufferLength
logPrintIO curLevel Verbose "receiving data"
eBufferLength <-
try $ recvBuf sock ptr maxBufferLength
logPrintIO curLevel Verbose $ "received raw buffer length of: " <> show eBufferLength
bufferLength <- case eBufferLength of
Left (e :: IOException) -> do
logPrintIO curLevel Warning ("Socket vanished, cleaning up after " <> show e)
dropClient curLevel socketList queueList sock
pure 0
Right len -> pure len
logPrintIO curLevel Verbose $ "received buffer of length: " <> show bufferLength
rawMsg <- B.pack <$> peekArray bufferLength ptr
free ptr
logPrintIO curLevel Verbose $ "received data: " <> show rawMsg
let msgs =
if B.length rawMsg < 1
then [] :: [B8.ByteString]
else map B8.tail $ init $ B8.split '>' $ B8.fromStrict rawMsg
logPrintIO curLevel Verbose $ "received messages: " <> show msgs
logPrintIO curLevel Verbose $ show msgs
mapM_
(\msg -> do
let mJsonMsg = A.decode' msg
maybe
(logPrintIO curLevel Warning $ "received garbled data: " <> B8.unpack (B8.fromStrict rawMsg))
(\jsonMsg -> do
STM.atomically $ STM.writeTQueue queue jsonMsg
)
mJsonMsg
)
msgs