Ticket #42: socket007.hs

{- server

As net003 but uses the BSD module for portability.  Also prints the
common name of the host rather than its IP number.

TESTS:
    getProtocolNumber
    getSocketName
    getHostByAddr

-}

module Main where

import BSD
import SocketPrim

main =
    getProtocolNumber "tcp"                     >>= \ proto ->
    socket AF_INET Stream proto                 >>= \ s ->
    bindSocket s (SockAddrInet aNY_PORT iNADDR_ANY)     >>
    getSocketName s                             >>= \ (SockAddrInet port _) ->
    putStr ("Allocated Port Number: " ++ show port ++ "\n") >>
    listen s 5                                  >>


    let 
      loop = 
        accept s                    >>= \ (s',(SockAddrInet _ haddr)) ->
        getHostByAddr AF_INET haddr             >>= \ (HostEntry hname _ _ _) ->
        putStr ("*** Start of Transfer from: " ++ hname ++ "***\n")     >>
        let 
          read_all = 
            readSocket s' 4                     >>= \ (str, nbytes) ->
            if nbytes /= 0 then
                putStr str                      >>
                read_all
            else
                putStr "\n*** End of Transfer ***\n" >>
                sClose s'
        in
            read_all    
    in
        loop