[GHC] #2795: The Network.Socket library does not take into account that the bits in the network are sent as big enddian.

[GHC]

#2795: The Network.Socket library does not take into account that the bits in the
network are sent as big enddian.
-----------------------------------------------------------------------+----
    Reporter:  guest                                                   |       Owner:                   
        Type:  bug                                                     |      Status:  new              
    Priority:  normal                                                  |   Component:  libraries/network
     Version:                                                          |    Severity:  major            
    Keywords:  socket port number big-enddian little-enddian conflict  |    Testcase:                   
Architecture:  x86                                                     |          Os:  Linux            
-----------------------------------------------------------------------+----
 We got the  program (1) below that is supposed to open a server in the
 port 51777. However, when we run the program, we observed that the port
 created was the number  16842. We believe that this difference comes from
 the fact that we run the program in a little enddian machine (Intel
 processor) and the socket library consider big enddian numbers instead. If
 we take 51777 and converted as indicated by function conv (see (2)), the
 socket open is indeed 51777.

 Kind regards,
 Alejandro Russo & Josef Svenningsson

 (1)

 import Network.Socket
 import System



 main = do s <- socket AF_INET Stream 0
           arg <- getArgs
           let shost = head arg
               port  = PortNum 51777
           host <- inet_addr shost
           putStrLn "Making the server..."
           bindSocket s (SockAddrInet port host)
           b <- sIsBound s
           putStrLn "Socket bounded!"
           listen s 5
           putStrLn "Listening OK"
           putStrLn "Waiting for clients..."
           (s', c) <- accept s
           putStrLn "Client found!"
           str <- recv s' 255
           putStr "Message received:"
           putStr str

 (2)

 conv :: Word16 -> Word16
 conv w16 = shiftL (fromIntegral a) 8 .|. fromIntegral b
            where a = fromIntegral w16 :: Word8
                  b = fromIntegral (shiftR w16 8) :: Word8

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2795>
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