TCP.hs

-- | OSC over TCP implementation.
module Sound.OSC.Transport.FD.TCP where

import qualified Data.ByteString.Lazy as B {- bytestring -}
import Control.Monad {- base -}
import qualified Network as N {- network -}
import System.IO {- base -}

import Sound.OSC.Coding.Class {- hosc -}
import Sound.OSC.Coding.Byte {- hosc -}
import Sound.OSC.Transport.FD {- hosc -}
import Sound.OSC.Packet.Class {- hosc -}

-- | The TCP transport handle data type.
data TCP = TCP {tcpHandle :: Handle}

-- | 'TCP' is an instance of 'Transport'.
instance Transport TCP where
   sendOSC (TCP fd) msg =
      do let b = encodeOSC msg
             n = fromIntegral (B.length b)
         B.hPut fd (B.append (encode_u32 n) b)
         hFlush fd
   recvPacket (TCP fd) =
      do b0 <- B.hGet fd 4
         b1 <- B.hGet fd (fromIntegral (decode_u32 b0))
         return (decodePacket b1)
   close (TCP fd) = hClose fd

{- | Make a 'TCP' connection.

> import Sound.OSC.Core
> import Sound.OSC.Transport.FD
> import Sound.OSC.Transport.FD.TCP
> let t = openTCP "127.0.0.1" 57110
> let m1 = message "/dumpOSC" [Int32 1]
> let m2 = message "/g_new" [Int32 1]
> withTransport t (\fd -> let f = sendMessage fd in f m1 >> f m2)

-}
openTCP :: String -> Int -> IO TCP
openTCP host =
    liftM TCP .
    N.connectTo host .
    N.PortNumber .
    fromIntegral

-- | A trivial 'TCP' /OSC/ server.
tcpServer' :: Int -> (TCP -> IO ()) -> IO ()
tcpServer' p f = do
  s <- N.listenOn (N.PortNumber (fromIntegral p))
  (sequence_ . repeat) (do (fd, _, _) <- N.accept s
                           f (TCP fd)
                           return ())