lib/hs/src/TSocket.hs

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-- to you under the Apache License, Version 2.0 (the
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--
--   http://www.apache.org/licenses/LICENSE-2.0
--
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module TSocket(TSocket(..)) where

import Thrift
import Data.IORef
import Network
import Control.Exception

import System.IO


data TSocket = TSocket{host::[Char],port::PortNumber,chan :: Maybe Handle}

instance TTransport TSocket where
    tisOpen a = case chan a of
                  Just _ -> True
                  Nothing -> False
    topen a = do h <- connectTo (host a) (PortNumber (port a))
                 return $ (a{chan = Just h})
    tclose a = case chan a of
                 Just h -> do hClose h
                              return $ a{chan=Nothing}
                 Nothing -> return a
    tread a 0 = return []
    tread a n = case chan a of
                  Just h -> handle (\e -> throwDyn (TransportExn "TSocket: Could not read." TE_UNKNOWN))
                      (do c <- hGetChar h
                          l <- tread a (n-1)
                          return $ c:l)
                  Nothing -> return []
    twrite a s = case chan a of
                   Just h -> hPutStr h s
                   Nothing -> return ()
    tflush a = case chan a of
                 Just h -> hFlush h
                 Nothing -> return ()