{-# LINE 1 "Network/Socket.hsc" #-}
{-# LANGUAGE CPP, ScopedTypeVariables #-}
{-# LINE 2 "Network/Socket.hsc" #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  Network.Socket
-- Copyright   :  (c) The University of Glasgow 2001
-- License     :  BSD-style (see the file libraries/network/LICENSE)
--
-- Maintainer  :  libraries@haskell.org
-- Stability   :  provisional
-- Portability :  portable
--
-- The "Network.Socket" module is for when you want full control over
-- sockets.  Essentially the entire C socket API is exposed through
-- this module; in general the operations follow the behaviour of the C
-- functions of the same name (consult your favourite Unix networking book).
--
-- A higher level interface to networking operations is provided
-- through the module "Network".
--
-----------------------------------------------------------------------------


{-# LINE 24 "Network/Socket.hsc" #-}

-- In order to process this file, you need to have CALLCONV defined.

module Network.Socket
    (
    -- * Types
      Socket(..)
    , Family(..)
    , isSupportedFamily
    , SocketType(..)
    , isSupportedSocketType
    , SockAddr(..)
    , SocketStatus(..)
    , HostAddress

{-# LINE 39 "Network/Socket.hsc" #-}
    , HostAddress6
    , FlowInfo
    , ScopeID

{-# LINE 43 "Network/Socket.hsc" #-}
    , ShutdownCmd(..)
    , ProtocolNumber
    , defaultProtocol
    , PortNumber(..)
    -- PortNumber is used non-abstractly in Network.BSD.  ToDo: remove
    -- this use and make the type abstract.

    -- * Address operations

    , HostName
    , ServiceName


{-# LINE 56 "Network/Socket.hsc" #-}
    , AddrInfo(..)

    , AddrInfoFlag(..)
    , addrInfoFlagImplemented

    , defaultHints

    , getAddrInfo

    , NameInfoFlag(..)

    , getNameInfo

{-# LINE 69 "Network/Socket.hsc" #-}

    -- * Socket operations
    , socket

{-# LINE 73 "Network/Socket.hsc" #-}
    , socketPair

{-# LINE 75 "Network/Socket.hsc" #-}
    , connect
    , bind
    , listen
    , accept
    , getPeerName
    , getSocketName


{-# LINE 83 "Network/Socket.hsc" #-}
    -- get the credentials of our domain socket peer.
    , getPeerCred

{-# LINE 88 "Network/Socket.hsc" #-}

{-# LINE 89 "Network/Socket.hsc" #-}

    , socketPort

    , socketToHandle

    -- ** Sending and receiving data
    -- $sendrecv
    , sendTo
    , sendBufTo

    , recvFrom
    , recvBufFrom

    , send
    , recv
    , recvLen
    , sendBuf
    , recvBuf

    , inet_addr
    , inet_ntoa

    , shutdown
    , close

    -- ** Predicates on sockets
    , isConnected
    , isBound
    , isListening
    , isReadable
    , isWritable

    -- * Socket options
    , SocketOption(..)
    , isSupportedSocketOption
    , getSocketOption
    , setSocketOption

    -- * File descriptor transmission

{-# LINE 129 "Network/Socket.hsc" #-}
    , sendFd
    , recvFd


{-# LINE 133 "Network/Socket.hsc" #-}

    -- * Special constants
    , aNY_PORT
    , iNADDR_ANY

{-# LINE 138 "Network/Socket.hsc" #-}
    , iN6ADDR_ANY

{-# LINE 140 "Network/Socket.hsc" #-}
    , sOMAXCONN
    , sOL_SOCKET

{-# LINE 143 "Network/Socket.hsc" #-}
    , sCM_RIGHTS

{-# LINE 145 "Network/Socket.hsc" #-}
    , maxListenQueue

    -- * Initialisation
    , withSocketsDo

    -- * Very low level operations
    -- in case you ever want to get at the underlying file descriptor..
    , fdSocket
    , mkSocket

    -- * Deprecated aliases
    -- $deprecated-aliases
    , bindSocket
    , sClose
    , sIsConnected
    , sIsBound
    , sIsListening
    , sIsReadable
    , sIsWritable

    -- * Internal

    -- | The following are exported ONLY for use in the BSD module and
    -- should not be used anywhere else.

    , packFamily
    , unpackFamily
    , packSocketType
    ) where

import Data.Bits
import Data.List (delete, foldl')
import Data.Maybe (isJust)
import Data.Word (Word8, Word32)
import Foreign.Ptr (Ptr, castPtr, nullPtr)
import Foreign.Storable (Storable(..))
import Foreign.C.Error
import Foreign.C.String (CString, withCString, withCStringLen, peekCString, peekCStringLen)
import Foreign.C.Types (CUInt, CChar)
import Foreign.C.Types (CInt(..), CSize(..))
import Foreign.Marshal.Alloc ( alloca, allocaBytes )
import Foreign.Marshal.Array ( peekArray )
import Foreign.Marshal.Utils ( maybeWith, with )

import System.IO
import Control.Monad (liftM, when)

import qualified Control.Exception as E
import Control.Concurrent.MVar
import Data.Typeable
import System.IO.Error

import GHC.Conc (threadWaitRead, threadWaitWrite)
#if MIN_VERSION_base(4,3,1)
import GHC.Conc (closeFdWith)
#endif

{-# LINE 205 "Network/Socket.hsc" #-}
import qualified GHC.IO.Device
import GHC.IO.Handle.FD
import GHC.IO.Exception
import GHC.IO
import qualified System.Posix.Internals

import GHC.IO.FD

import Network.Socket.Internal
import Network.Socket.Types

-- | Either a host name e.g., @\"haskell.org\"@ or a numeric host
-- address string consisting of a dotted decimal IPv4 address or an
-- IPv6 address e.g., @\"192.168.0.1\"@.
type HostName       = String
type ServiceName    = String

-- ----------------------------------------------------------------------------
-- On Windows, our sockets are not put in non-blocking mode (non-blocking
-- is not supported for regular file descriptors on Windows, and it would
-- be a pain to support it only for sockets).  So there are two cases:
--
--  - the threaded RTS uses safe calls for socket operations to get
--    non-blocking I/O, just like the rest of the I/O library
--
--  - with the non-threaded RTS, only some operations on sockets will be
--    non-blocking.  Reads and writes go through the normal async I/O
--    system.  accept() uses asyncDoProc so is non-blocking.  A handful
--    of others (recvFrom, sendFd, recvFd) will block all threads - if this
--    is a problem, -threaded is the workaround.
--
#if defined(mingw32_HOST_OS)
#define SAFE_ON_WIN safe
#else
#define SAFE_ON_WIN unsafe
#endif

-----------------------------------------------------------------------------
-- Socket types


{-# LINE 250 "Network/Socket.hsc" #-}

mkSocket :: CInt
         -> Family
         -> SocketType
         -> ProtocolNumber
         -> SocketStatus
         -> IO Socket
mkSocket fd fam sType pNum stat = do
   mStat <- newMVar stat
   return (MkSocket fd fam sType pNum mStat)


fdSocket :: Socket -> CInt
fdSocket (MkSocket fd _ _ _ _) = fd

-- | This is the default protocol for a given service.
defaultProtocol :: ProtocolNumber
defaultProtocol = 0

-----------------------------------------------------------------------------
-- SockAddr

instance Show SockAddr where

{-# LINE 274 "Network/Socket.hsc" #-}
  showsPrec _ (SockAddrUnix str) = showString str

{-# LINE 276 "Network/Socket.hsc" #-}
  showsPrec _ (SockAddrInet port ha)
   = showString (unsafePerformIO (inet_ntoa ha))
   . showString ":"
   . shows port

{-# LINE 281 "Network/Socket.hsc" #-}
  showsPrec _ addr@(SockAddrInet6 port _ _ _)
   = showChar '['
   . showString (unsafePerformIO $
                 fst `liftM` getNameInfo [NI_NUMERICHOST] True False addr >>=
                 maybe (fail "showsPrec: impossible internal error") return)
   . showString "]:"
   . shows port

{-# LINE 289 "Network/Socket.hsc" #-}

-----------------------------------------------------------------------------
-- Connection Functions

-- In the following connection and binding primitives.  The names of
-- the equivalent C functions have been preserved where possible. It
-- should be noted that some of these names used in the C library,
-- \tr{bind} in particular, have a different meaning to many Haskell
-- programmers and have thus been renamed by appending the prefix
-- Socket.

-- | Create a new socket using the given address family, socket type
-- and protocol number.  The address family is usually 'AF_INET',
-- 'AF_INET6', or 'AF_UNIX'.  The socket type is usually 'Stream' or
-- 'Datagram'.  The protocol number is usually 'defaultProtocol'.
-- If 'AF_INET6' is used, the 'IPv6Only' socket option is set to 0
-- so that both IPv4 and IPv6 can be handled with one socket.
socket :: Family         -- Family Name (usually AF_INET)
       -> SocketType     -- Socket Type (usually Stream)
       -> ProtocolNumber -- Protocol Number (getProtocolByName to find value)
       -> IO Socket      -- Unconnected Socket
socket family stype protocol = do
    c_stype <- packSocketTypeOrThrow "socket" stype
    fd <- throwSocketErrorIfMinus1Retry "socket" $
                c_socket (packFamily family) c_stype protocol
    setNonBlockIfNeeded fd
    socket_status <- newMVar NotConnected
    let sock = MkSocket fd family stype protocol socket_status

{-# LINE 318 "Network/Socket.hsc" #-}

{-# LINE 324 "Network/Socket.hsc" #-}
    when (family == AF_INET6) $ setSocketOption sock IPv6Only 0

{-# LINE 326 "Network/Socket.hsc" #-}

{-# LINE 327 "Network/Socket.hsc" #-}
    return sock

-- | Build a pair of connected socket objects using the given address
-- family, socket type, and protocol number.  Address family, socket
-- type, and protocol number are as for the 'socket' function above.
-- Availability: Unix.

{-# LINE 334 "Network/Socket.hsc" #-}
socketPair :: Family              -- Family Name (usually AF_INET or AF_INET6)
           -> SocketType          -- Socket Type (usually Stream)
           -> ProtocolNumber      -- Protocol Number
           -> IO (Socket, Socket) -- unnamed and connected.
socketPair family stype protocol = do
    allocaBytes (2 * sizeOf (1 :: CInt)) $ \ fdArr -> do
    c_stype <- packSocketTypeOrThrow "socketPair" stype
    _rc <- throwSocketErrorIfMinus1Retry "socketpair" $
                c_socketpair (packFamily family) c_stype protocol fdArr
    [fd1,fd2] <- peekArray 2 fdArr
    s1 <- mkNonBlockingSocket fd1
    s2 <- mkNonBlockingSocket fd2
    return (s1,s2)
  where
    mkNonBlockingSocket fd = do
       setNonBlockIfNeeded fd
       stat <- newMVar Connected
       return (MkSocket fd family stype protocol stat)

foreign import ccall unsafe "socketpair"
  c_socketpair :: CInt -> CInt -> CInt -> Ptr CInt -> IO CInt

{-# LINE 356 "Network/Socket.hsc" #-}

-- | Set the socket to nonblocking, if applicable to this platform.
setNonBlockIfNeeded :: CInt -> IO ()
setNonBlockIfNeeded fd =
    System.Posix.Internals.setNonBlockingFD fd True

-----------------------------------------------------------------------------
-- Binding a socket

-- | Bind the socket to an address. The socket must not already be
-- bound.  The 'Family' passed to @bind@ must be the
-- same as that passed to 'socket'.  If the special port number
-- 'aNY_PORT' is passed then the system assigns the next available
-- use port.
bind :: Socket    -- Unconnected Socket
           -> SockAddr  -- Address to Bind to
           -> IO ()
bind (MkSocket s _family _stype _protocol socketStatus) addr = do
 modifyMVar_ socketStatus $ \ status -> do
 if status /= NotConnected
  then
   ioError (userError ("bind: can't peform bind on socket in status " ++
         show status))
  else do
   withSockAddr addr $ \p_addr sz -> do
   _status <- throwSocketErrorIfMinus1Retry "bind" $ c_bind s p_addr (fromIntegral sz)
   return Bound

-----------------------------------------------------------------------------
-- Connecting a socket

-- | Connect to a remote socket at address.
connect :: Socket    -- Unconnected Socket
        -> SockAddr  -- Socket address stuff
        -> IO ()
connect sock@(MkSocket s _family _stype _protocol socketStatus) addr = do
 modifyMVar_ socketStatus $ \currentStatus -> do
 if currentStatus /= NotConnected && currentStatus /= Bound
  then
    ioError (userError ("connect: can't peform connect on socket in status " ++
        show currentStatus))
  else do
    withSockAddr addr $ \p_addr sz -> do

    let connectLoop = do
           r <- c_connect s p_addr (fromIntegral sz)
           if r == -1
               then do

{-# LINE 405 "Network/Socket.hsc" #-}
                   err <- getErrno
                   case () of
                     _ | err == eINTR       -> connectLoop
                     _ | err == eINPROGRESS -> connectBlocked
--                   _ | err == eAGAIN      -> connectBlocked
                     _otherwise             -> throwSocketError "connect"

{-# LINE 422 "Network/Socket.hsc" #-}
               else return ()

        connectBlocked = do
           threadWaitWrite (fromIntegral s)
           err <- getSocketOption sock SoError
           if (err == 0)
                then return ()
                else throwSocketErrorCode "connect" (fromIntegral err)

    connectLoop
    return Connected

-----------------------------------------------------------------------------
-- Listen

-- | Listen for connections made to the socket.  The second argument
-- specifies the maximum number of queued connections and should be at
-- least 1; the maximum value is system-dependent (usually 5).
listen :: Socket  -- Connected & Bound Socket
       -> Int     -- Queue Length
       -> IO ()
listen (MkSocket s _family _stype _protocol socketStatus) backlog = do
 modifyMVar_ socketStatus $ \ status -> do
 if status /= Bound
   then
     ioError (userError ("listen: can't peform listen on socket in status " ++
         show status))
   else do
     throwSocketErrorIfMinus1Retry_ "listen" (c_listen s (fromIntegral backlog))
     return Listening

-----------------------------------------------------------------------------
-- Accept
--
-- A call to `accept' only returns when data is available on the given
-- socket, unless the socket has been set to non-blocking.  It will
-- return a new socket which should be used to read the incoming data and
-- should then be closed. Using the socket returned by `accept' allows
-- incoming requests to be queued on the original socket.

-- | Accept a connection.  The socket must be bound to an address and
-- listening for connections.  The return value is a pair @(conn,
-- address)@ where @conn@ is a new socket object usable to send and
-- receive data on the connection, and @address@ is the address bound
-- to the socket on the other end of the connection.
accept :: Socket                        -- Queue Socket
       -> IO (Socket,                   -- Readable Socket
              SockAddr)                 -- Peer details

accept sock@(MkSocket s family stype protocol status) = do
 currentStatus <- readMVar status
 okay <- isAcceptable sock
 if not okay
   then
     ioError (userError ("accept: can't perform accept on socket (" ++ (show (family,stype,protocol)) ++") in status " ++
         show currentStatus))
   else do
     let sz = sizeOfSockAddrByFamily family
     allocaBytes sz $ \ sockaddr -> do

{-# LINE 496 "Network/Socket.hsc" #-}
     with (fromIntegral sz) $ \ ptr_len -> do

{-# LINE 498 "Network/Socket.hsc" #-}
     new_sock <- throwSocketErrorIfMinus1RetryMayBlock "accept"
                        (threadWaitRead (fromIntegral s))
                        (c_accept4 s sockaddr ptr_len (2048))
{-# LINE 501 "Network/Socket.hsc" #-}

{-# LINE 506 "Network/Socket.hsc" #-}

{-# LINE 507 "Network/Socket.hsc" #-}
     addr <- peekSockAddr sockaddr
     new_status <- newMVar Connected
     return ((MkSocket new_sock family stype protocol new_status), addr)


{-# LINE 521 "Network/Socket.hsc" #-}

-----------------------------------------------------------------------------
-- ** Sending and reciving data

-- $sendrecv
--
-- Do not use the @send@ and @recv@ functions defined in this module
-- in new code, as they incorrectly represent binary data as a Unicode
-- string.  As a result, these functions are inefficient and may lead
-- to bugs in the program.  Instead use the @send@ and @recv@
-- functions defined in the 'Network.Socket.ByteString' module.

-----------------------------------------------------------------------------
-- sendTo & recvFrom

-- | Send data to the socket.  The recipient can be specified
-- explicitly, so the socket need not be in a connected state.
-- Returns the number of bytes sent.  Applications are responsible for
-- ensuring that all data has been sent.
--
-- NOTE: blocking on Windows unless you compile with -threaded (see
-- GHC ticket #1129)
sendTo :: Socket        -- (possibly) bound/connected Socket
       -> String        -- Data to send
       -> SockAddr
       -> IO Int        -- Number of Bytes sent
sendTo sock xs addr = do
 withCStringLen xs $ \(str, len) -> do
   sendBufTo sock str len addr

-- | Send data to the socket.  The recipient can be specified
-- explicitly, so the socket need not be in a connected state.
-- Returns the number of bytes sent.  Applications are responsible for
-- ensuring that all data has been sent.
sendBufTo :: Socket            -- (possibly) bound/connected Socket
          -> Ptr a -> Int  -- Data to send
          -> SockAddr
          -> IO Int            -- Number of Bytes sent
sendBufTo sock@(MkSocket s _family _stype _protocol _status) ptr nbytes addr = do
 withSockAddr addr $ \p_addr sz -> do
   liftM fromIntegral $
     throwSocketErrorWaitWrite sock "sendTo" $
        c_sendto s ptr (fromIntegral $ nbytes) 0{-flags-}
                        p_addr (fromIntegral sz)

-- | Receive data from the socket. The socket need not be in a
-- connected state. Returns @(bytes, nbytes, address)@ where @bytes@
-- is a @String@ of length @nbytes@ representing the data received and
-- @address@ is a 'SockAddr' representing the address of the sending
-- socket.
--
-- NOTE: blocking on Windows unless you compile with -threaded (see
-- GHC ticket #1129)
recvFrom :: Socket -> Int -> IO (String, Int, SockAddr)
recvFrom sock nbytes =
  allocaBytes nbytes $ \ptr -> do
    (len, sockaddr) <- recvBufFrom sock ptr nbytes
    str <- peekCStringLen (ptr, len)
    return (str, len, sockaddr)

-- | Receive data from the socket, writing it into buffer instead of
-- creating a new string.  The socket need not be in a connected
-- state. Returns @(nbytes, address)@ where @nbytes@ is the number of
-- bytes received and @address@ is a 'SockAddr' representing the
-- address of the sending socket.
--
-- NOTE: blocking on Windows unless you compile with -threaded (see
-- GHC ticket #1129)
recvBufFrom :: Socket -> Ptr a -> Int -> IO (Int, SockAddr)
recvBufFrom sock@(MkSocket s family _stype _protocol _status) ptr nbytes
 | nbytes <= 0 = ioError (mkInvalidRecvArgError "Network.Socket.recvFrom")
 | otherwise   =
    withNewSockAddr family $ \ptr_addr sz -> do
      alloca $ \ptr_len -> do
        poke ptr_len (fromIntegral sz)
        len <- throwSocketErrorWaitRead sock "recvFrom" $
                   c_recvfrom s ptr (fromIntegral nbytes) 0{-flags-}
                                ptr_addr ptr_len
        let len' = fromIntegral len
        if len' == 0
         then ioError (mkEOFError "Network.Socket.recvFrom")
         else do
           flg <- isConnected sock
             -- For at least one implementation (WinSock 2), recvfrom() ignores
             -- filling in the sockaddr for connected TCP sockets. Cope with
             -- this by using getPeerName instead.
           sockaddr <-
                if flg then
                   getPeerName sock
                else
                   peekSockAddr ptr_addr
           return (len', sockaddr)

-----------------------------------------------------------------------------
-- send & recv

-- | Send data to the socket. The socket must be connected to a remote
-- socket. Returns the number of bytes sent.  Applications are
-- responsible for ensuring that all data has been sent.
send :: Socket  -- Bound/Connected Socket
     -> String  -- Data to send
     -> IO Int  -- Number of Bytes sent
send sock@(MkSocket s _family _stype _protocol _status) xs = do
 withCStringLen xs $ \(str, len) -> do
   liftM fromIntegral $

{-# LINE 634 "Network/Socket.hsc" #-}
     throwSocketErrorWaitWrite sock "send" $
        c_send s str (fromIntegral len) 0{-flags-}

{-# LINE 637 "Network/Socket.hsc" #-}

-- | Send data to the socket. The socket must be connected to a remote
-- socket. Returns the number of bytes sent.  Applications are
-- responsible for ensuring that all data has been sent.
sendBuf :: Socket     -- Bound/Connected Socket
        -> Ptr Word8  -- Pointer to the data to send
        -> Int        -- Length of the buffer
        -> IO Int     -- Number of Bytes sent
sendBuf sock@(MkSocket s _family _stype _protocol _status) str len = do
   liftM fromIntegral $

{-# LINE 655 "Network/Socket.hsc" #-}
     throwSocketErrorWaitWrite sock "sendBuf" $
        c_send s str (fromIntegral len) 0{-flags-}

{-# LINE 658 "Network/Socket.hsc" #-}


-- | Receive data from the socket.  The socket must be in a connected
-- state. This function may return fewer bytes than specified.  If the
-- message is longer than the specified length, it may be discarded
-- depending on the type of socket.  This function may block until a
-- message arrives.
--
-- Considering hardware and network realities, the maximum number of
-- bytes to receive should be a small power of 2, e.g., 4096.
--
-- For TCP sockets, a zero length return value means the peer has
-- closed its half side of the connection.
recv :: Socket -> Int -> IO String
recv sock l = recvLen sock l >>= \ (s,_) -> return s

recvLen :: Socket -> Int -> IO (String, Int)
recvLen sock@(MkSocket s _family _stype _protocol _status) nbytes
 | nbytes <= 0 = ioError (mkInvalidRecvArgError "Network.Socket.recv")
 | otherwise   = do
     allocaBytes nbytes $ \ptr -> do
        len <-

{-# LINE 684 "Network/Socket.hsc" #-}
               throwSocketErrorWaitRead sock "recv" $
                   c_recv s ptr (fromIntegral nbytes) 0{-flags-}

{-# LINE 687 "Network/Socket.hsc" #-}
        let len' = fromIntegral len
        if len' == 0
         then ioError (mkEOFError "Network.Socket.recv")
         else do
           s' <- peekCStringLen (castPtr ptr,len')
           return (s', len')

-- | Receive data from the socket.  The socket must be in a connected
-- state. This function may return fewer bytes than specified.  If the
-- message is longer than the specified length, it may be discarded
-- depending on the type of socket.  This function may block until a
-- message arrives.
--
-- Considering hardware and network realities, the maximum number of
-- bytes to receive should be a small power of 2, e.g., 4096.
--
-- For TCP sockets, a zero length return value means the peer has
-- closed its half side of the connection.
recvBuf :: Socket -> Ptr Word8 -> Int -> IO Int
recvBuf sock p l = recvLenBuf sock p l

recvLenBuf :: Socket -> Ptr Word8 -> Int -> IO Int
recvLenBuf sock@(MkSocket s _family _stype _protocol _status) ptr nbytes
 | nbytes <= 0 = ioError (mkInvalidRecvArgError "Network.Socket.recvBuf")
 | otherwise   = do
        len <-

{-# LINE 717 "Network/Socket.hsc" #-}
               throwSocketErrorWaitRead sock "recvBuf" $
                   c_recv s (castPtr ptr) (fromIntegral nbytes) 0{-flags-}

{-# LINE 720 "Network/Socket.hsc" #-}
        let len' = fromIntegral len
        if len' == 0
         then ioError (mkEOFError "Network.Socket.recvBuf")
         else return len'


-- ---------------------------------------------------------------------------
-- socketPort
--
-- The port number the given socket is currently connected to can be
-- determined by calling $port$, is generally only useful when bind
-- was given $aNY\_PORT$.

socketPort :: Socket            -- Connected & Bound Socket
           -> IO PortNumber     -- Port Number of Socket
socketPort sock@(MkSocket _ AF_INET _ _ _) = do
    (SockAddrInet port _) <- getSocketName sock
    return port

{-# LINE 739 "Network/Socket.hsc" #-}
socketPort sock@(MkSocket _ AF_INET6 _ _ _) = do
    (SockAddrInet6 port _ _ _) <- getSocketName sock
    return port

{-# LINE 743 "Network/Socket.hsc" #-}
socketPort (MkSocket _ family _ _ _) =
    ioError (userError ("socketPort: not supported for Family " ++ show family))


-- ---------------------------------------------------------------------------
-- getPeerName

-- Calling $getPeerName$ returns the address details of the machine,
-- other than the local one, which is connected to the socket. This is
-- used in programs such as FTP to determine where to send the
-- returning data.  The corresponding call to get the details of the
-- local machine is $getSocketName$.

getPeerName   :: Socket -> IO SockAddr
getPeerName (MkSocket s family _ _ _) = do
 withNewSockAddr family $ \ptr sz -> do
   with (fromIntegral sz) $ \int_star -> do
   throwSocketErrorIfMinus1Retry_ "getPeerName" $ c_getpeername s ptr int_star
   _sz <- peek int_star
   peekSockAddr ptr

getSocketName :: Socket -> IO SockAddr
getSocketName (MkSocket s family _ _ _) = do
 withNewSockAddr family $ \ptr sz -> do
   with (fromIntegral sz) $ \int_star -> do
   throwSocketErrorIfMinus1Retry_ "getSocketName" $ c_getsockname s ptr int_star
   peekSockAddr ptr

-----------------------------------------------------------------------------
-- Socket Properties

-- | Socket options for use with 'setSocketOption' and 'getSocketOption'.
--
-- The existence of a constructor does not imply that the relevant option
-- is supported on your system: see 'isSupportedSocketOption'
data SocketOption
    = Debug         -- ^ SO_DEBUG
    | ReuseAddr     -- ^ SO_REUSEADDR
    | Type          -- ^ SO_TYPE
    | SoError       -- ^ SO_ERROR
    | DontRoute     -- ^ SO_DONTROUTE
    | Broadcast     -- ^ SO_BROADCAST
    | SendBuffer    -- ^ SO_SNDBUF
    | RecvBuffer    -- ^ SO_RCVBUF
    | KeepAlive     -- ^ SO_KEEPALIVE
    | OOBInline     -- ^ SO_OOBINLINE
    | TimeToLive    -- ^ IP_TTL
    | MaxSegment    -- ^ TCP_MAXSEG
    | NoDelay       -- ^ TCP_NODELAY
    | Cork          -- ^ TCP_CORK
    | Linger        -- ^ SO_LINGER
    | ReusePort     -- ^ SO_REUSEPORT
    | RecvLowWater  -- ^ SO_RCVLOWAT
    | SendLowWater  -- ^ SO_SNDLOWAT
    | RecvTimeOut   -- ^ SO_RCVTIMEO
    | SendTimeOut   -- ^ SO_SNDTIMEO
    | UseLoopBack   -- ^ SO_USELOOPBACK
    | IPv6Only      -- ^ IPV6_V6ONLY
    | CustomSockOpt (CInt, CInt)
    deriving (Show, Typeable)

-- | Does the 'SocketOption' exist on this system?
isSupportedSocketOption :: SocketOption -> Bool
isSupportedSocketOption = isJust . packSocketOption

-- | For a socket option, return Just (level, value) where level is the
-- corresponding C option level constant (e.g. SOL_SOCKET) and value is
-- the option constant itself (e.g. SO_DEBUG)
-- If either constant does not exist, return Nothing.
packSocketOption :: SocketOption -> Maybe (CInt, CInt)
packSocketOption so =
  -- The Just here is a hack to disable GHC's overlapping pattern detection:
  -- the problem is if all constants are present, the fallback pattern is
  -- redundant, but if they aren't then it isn't. Hence we introduce an
  -- extra pattern (Nothing) that can't possibly happen, so that the
  -- fallback is always (in principle) necessary.
  -- I feel a little bad for including this, but such are the sacrifices we
  -- make while working with CPP - excluding the fallback pattern correctly
  -- would be a serious nuisance.
  -- (NB: comments elsewhere in this file refer to this one)
  case Just so of

{-# LINE 825 "Network/Socket.hsc" #-}

{-# LINE 826 "Network/Socket.hsc" #-}
    Just Debug         -> Just ((1), (1))
{-# LINE 827 "Network/Socket.hsc" #-}

{-# LINE 828 "Network/Socket.hsc" #-}

{-# LINE 829 "Network/Socket.hsc" #-}
    Just ReuseAddr     -> Just ((1), (2))
{-# LINE 830 "Network/Socket.hsc" #-}

{-# LINE 831 "Network/Socket.hsc" #-}

{-# LINE 832 "Network/Socket.hsc" #-}
    Just Type          -> Just ((1), (3))
{-# LINE 833 "Network/Socket.hsc" #-}

{-# LINE 834 "Network/Socket.hsc" #-}

{-# LINE 835 "Network/Socket.hsc" #-}
    Just SoError       -> Just ((1), (4))
{-# LINE 836 "Network/Socket.hsc" #-}

{-# LINE 837 "Network/Socket.hsc" #-}

{-# LINE 838 "Network/Socket.hsc" #-}
    Just DontRoute     -> Just ((1), (5))
{-# LINE 839 "Network/Socket.hsc" #-}

{-# LINE 840 "Network/Socket.hsc" #-}

{-# LINE 841 "Network/Socket.hsc" #-}
    Just Broadcast     -> Just ((1), (6))
{-# LINE 842 "Network/Socket.hsc" #-}

{-# LINE 843 "Network/Socket.hsc" #-}

{-# LINE 844 "Network/Socket.hsc" #-}
    Just SendBuffer    -> Just ((1), (7))
{-# LINE 845 "Network/Socket.hsc" #-}

{-# LINE 846 "Network/Socket.hsc" #-}

{-# LINE 847 "Network/Socket.hsc" #-}
    Just RecvBuffer    -> Just ((1), (8))
{-# LINE 848 "Network/Socket.hsc" #-}

{-# LINE 849 "Network/Socket.hsc" #-}

{-# LINE 850 "Network/Socket.hsc" #-}
    Just KeepAlive     -> Just ((1), (9))
{-# LINE 851 "Network/Socket.hsc" #-}

{-# LINE 852 "Network/Socket.hsc" #-}

{-# LINE 853 "Network/Socket.hsc" #-}
    Just OOBInline     -> Just ((1), (10))
{-# LINE 854 "Network/Socket.hsc" #-}

{-# LINE 855 "Network/Socket.hsc" #-}

{-# LINE 856 "Network/Socket.hsc" #-}
    Just Linger        -> Just ((1), (13))
{-# LINE 857 "Network/Socket.hsc" #-}

{-# LINE 858 "Network/Socket.hsc" #-}

{-# LINE 861 "Network/Socket.hsc" #-}

{-# LINE 862 "Network/Socket.hsc" #-}
    Just RecvLowWater  -> Just ((1), (18))
{-# LINE 863 "Network/Socket.hsc" #-}

{-# LINE 864 "Network/Socket.hsc" #-}

{-# LINE 865 "Network/Socket.hsc" #-}
    Just SendLowWater  -> Just ((1), (19))
{-# LINE 866 "Network/Socket.hsc" #-}

{-# LINE 867 "Network/Socket.hsc" #-}

{-# LINE 868 "Network/Socket.hsc" #-}
    Just RecvTimeOut   -> Just ((1), (20))
{-# LINE 869 "Network/Socket.hsc" #-}

{-# LINE 870 "Network/Socket.hsc" #-}

{-# LINE 871 "Network/Socket.hsc" #-}
    Just SendTimeOut   -> Just ((1), (21))
{-# LINE 872 "Network/Socket.hsc" #-}

{-# LINE 873 "Network/Socket.hsc" #-}

{-# LINE 876 "Network/Socket.hsc" #-}

{-# LINE 877 "Network/Socket.hsc" #-}

{-# LINE 878 "Network/Socket.hsc" #-}

{-# LINE 879 "Network/Socket.hsc" #-}
    Just TimeToLive    -> Just ((0), (2))
{-# LINE 880 "Network/Socket.hsc" #-}

{-# LINE 881 "Network/Socket.hsc" #-}

{-# LINE 882 "Network/Socket.hsc" #-}

{-# LINE 883 "Network/Socket.hsc" #-}

{-# LINE 884 "Network/Socket.hsc" #-}
    Just MaxSegment    -> Just ((6), (2))
{-# LINE 885 "Network/Socket.hsc" #-}

{-# LINE 886 "Network/Socket.hsc" #-}

{-# LINE 887 "Network/Socket.hsc" #-}
    Just NoDelay       -> Just ((6), (1))
{-# LINE 888 "Network/Socket.hsc" #-}

{-# LINE 889 "Network/Socket.hsc" #-}

{-# LINE 890 "Network/Socket.hsc" #-}
    Just Cork          -> Just ((6), (3))
{-# LINE 891 "Network/Socket.hsc" #-}

{-# LINE 892 "Network/Socket.hsc" #-}

{-# LINE 893 "Network/Socket.hsc" #-}

{-# LINE 894 "Network/Socket.hsc" #-}

{-# LINE 895 "Network/Socket.hsc" #-}
    Just IPv6Only      -> Just ((41), (26))
{-# LINE 896 "Network/Socket.hsc" #-}

{-# LINE 897 "Network/Socket.hsc" #-}

{-# LINE 898 "Network/Socket.hsc" #-}
    Just (CustomSockOpt opt) -> Just opt
    _             -> Nothing

-- | Return the option level and option value if they exist,
-- otherwise throw an error that begins "Network.Socket." ++ the String
-- parameter
packSocketOption' :: String -> SocketOption -> IO (CInt, CInt)
packSocketOption' caller so = maybe err return (packSocketOption so)
 where
  err = ioError . userError . concat $ ["Network.Socket.", caller,
    ": socket option ", show so, " unsupported on this system"]

-- | Set a socket option that expects an Int value.
-- There is currently no API to set e.g. the timeval socket options
setSocketOption :: Socket
                -> SocketOption -- Option Name
                -> Int          -- Option Value
                -> IO ()
setSocketOption (MkSocket s _ _ _ _) so v = do
   (level, opt) <- packSocketOption' "setSocketOption" so
   with (fromIntegral v) $ \ptr_v -> do
   throwSocketErrorIfMinus1_ "setSocketOption" $
       c_setsockopt s level opt ptr_v
          (fromIntegral (sizeOf (undefined :: CInt)))
   return ()


-- | Get a socket option that gives an Int value.
-- There is currently no API to get e.g. the timeval socket options
getSocketOption :: Socket
                -> SocketOption  -- Option Name
                -> IO Int        -- Option Value
getSocketOption (MkSocket s _ _ _ _) so = do
   (level, opt) <- packSocketOption' "getSocketOption" so
   alloca $ \ptr_v ->
     with (fromIntegral (sizeOf (undefined :: CInt))) $ \ptr_sz -> do
       throwSocketErrorIfMinus1Retry_ "getSocketOption" $
         c_getsockopt s level opt ptr_v ptr_sz
       fromIntegral `liftM` peek ptr_v



{-# LINE 940 "Network/Socket.hsc" #-}
-- | Returns the processID, userID and groupID of the socket's peer.
--
-- Only available on platforms that support SO_PEERCRED or GETPEEREID(3)
-- on domain sockets.
-- GETPEEREID(3) returns userID and groupID. processID is always 0.
getPeerCred :: Socket -> IO (CUInt, CUInt, CUInt)
getPeerCred sock = do

{-# LINE 948 "Network/Socket.hsc" #-}
  let fd = fdSocket sock
  let sz = (fromIntegral (12))
{-# LINE 950 "Network/Socket.hsc" #-}
  with sz $ \ ptr_cr ->
   alloca       $ \ ptr_sz -> do
     poke ptr_sz sz
     throwSocketErrorIfMinus1Retry "getPeerCred" $
       c_getsockopt fd (1) (17) ptr_cr ptr_sz
{-# LINE 955 "Network/Socket.hsc" #-}
     pid <- ((\hsc_ptr -> peekByteOff hsc_ptr 0)) ptr_cr
{-# LINE 956 "Network/Socket.hsc" #-}
     uid <- ((\hsc_ptr -> peekByteOff hsc_ptr 4)) ptr_cr
{-# LINE 957 "Network/Socket.hsc" #-}
     gid <- ((\hsc_ptr -> peekByteOff hsc_ptr 8)) ptr_cr
{-# LINE 958 "Network/Socket.hsc" #-}
     return (pid, uid, gid)

{-# LINE 963 "Network/Socket.hsc" #-}


{-# LINE 978 "Network/Socket.hsc" #-}

{-# LINE 979 "Network/Socket.hsc" #-}

#if !(MIN_VERSION_base(4,3,1))
closeFdWith closer fd = closer fd
#endif


{-# LINE 985 "Network/Socket.hsc" #-}
-- sending/receiving ancillary socket data; low-level mechanism
-- for transmitting file descriptors, mainly.
sendFd :: Socket -> CInt -> IO ()
sendFd sock outfd = do
  throwSocketErrorWaitWrite sock "sendFd" $
     c_sendFd (fdSocket sock) outfd
   -- Note: If Winsock supported FD-passing, thi would have been
   -- incorrect (since socket FDs need to be closed via closesocket().)
  closeFd outfd

recvFd :: Socket -> IO CInt
recvFd sock = do
  theFd <- throwSocketErrorWaitRead sock "recvFd" $
               c_recvFd (fdSocket sock)
  return theFd

foreign import ccall SAFE_ON_WIN "sendFd" c_sendFd :: CInt -> CInt -> IO CInt
foreign import ccall SAFE_ON_WIN "recvFd" c_recvFd :: CInt -> IO CInt


{-# LINE 1005 "Network/Socket.hsc" #-}

-- ---------------------------------------------------------------------------
-- Utility Functions

aNY_PORT :: PortNumber
aNY_PORT = 0

-- | The IPv4 wild card address.

iNADDR_ANY :: HostAddress
iNADDR_ANY = htonl (0)
{-# LINE 1016 "Network/Socket.hsc" #-}

foreign import CALLCONV unsafe "htonl" htonl :: Word32 -> Word32


{-# LINE 1020 "Network/Socket.hsc" #-}
-- | The IPv6 wild card address.

iN6ADDR_ANY :: HostAddress6
iN6ADDR_ANY = (0, 0, 0, 0)

{-# LINE 1025 "Network/Socket.hsc" #-}

sOMAXCONN :: Int
sOMAXCONN = 128
{-# LINE 1028 "Network/Socket.hsc" #-}

sOL_SOCKET :: Int
sOL_SOCKET = 1
{-# LINE 1031 "Network/Socket.hsc" #-}


{-# LINE 1033 "Network/Socket.hsc" #-}
sCM_RIGHTS :: Int
sCM_RIGHTS = 1
{-# LINE 1035 "Network/Socket.hsc" #-}

{-# LINE 1036 "Network/Socket.hsc" #-}

-- | This is the value of SOMAXCONN, typically 128.
-- 128 is good enough for normal network servers but
-- is too small for high performance servers.
maxListenQueue :: Int
maxListenQueue = sOMAXCONN

-- -----------------------------------------------------------------------------

data ShutdownCmd
 = ShutdownReceive
 | ShutdownSend
 | ShutdownBoth
 deriving Typeable

sdownCmdToInt :: ShutdownCmd -> CInt
sdownCmdToInt ShutdownReceive = 0
sdownCmdToInt ShutdownSend    = 1
sdownCmdToInt ShutdownBoth    = 2

-- | Shut down one or both halves of the connection, depending on the
-- second argument to the function.  If the second argument is
-- 'ShutdownReceive', further receives are disallowed.  If it is
-- 'ShutdownSend', further sends are disallowed.  If it is
-- 'ShutdownBoth', further sends and receives are disallowed.
shutdown :: Socket -> ShutdownCmd -> IO ()
shutdown (MkSocket s _ _ _ _) stype = do
  throwSocketErrorIfMinus1Retry_ "shutdown" (c_shutdown s (sdownCmdToInt stype))
  return ()

-- -----------------------------------------------------------------------------

-- | Close the socket.  All future operations on the socket object
-- will fail.  The remote end will receive no more data (after queued
-- data is flushed).
close :: Socket -> IO ()
close (MkSocket s _ _ _ socketStatus) = do
 modifyMVar_ socketStatus $ \ status ->
   case status of
     ConvertedToHandle ->
         ioError (userError ("close: converted to a Handle, use hClose instead"))
     Closed ->
         return status
     _ -> closeFdWith (closeFd . fromIntegral) (fromIntegral s) >> return Closed

-- -----------------------------------------------------------------------------

-- | Determines whether 'close' has been used on the 'Socket'. This
-- does /not/ indicate any status about the socket beyond this. If the
-- socket has been closed remotely, this function can still return
-- 'True'.
isConnected :: Socket -> IO Bool
isConnected (MkSocket _ _ _ _ status) = do
    value <- readMVar status
    return (value == Connected)

-- -----------------------------------------------------------------------------
-- Socket Predicates

isBound :: Socket -> IO Bool
isBound (MkSocket _ _ _ _ status) = do
    value <- readMVar status
    return (value == Bound)

isListening :: Socket -> IO Bool
isListening (MkSocket _ _ _  _ status) = do
    value <- readMVar status
    return (value == Listening)

isReadable  :: Socket -> IO Bool
isReadable (MkSocket _ _ _ _ status) = do
    value <- readMVar status
    return (value == Listening || value == Connected)

isWritable  :: Socket -> IO Bool
isWritable = isReadable -- sort of.

isAcceptable :: Socket -> IO Bool

{-# LINE 1115 "Network/Socket.hsc" #-}
isAcceptable (MkSocket _ AF_UNIX x _ status)
    | x == Stream || x == SeqPacket = do
        value <- readMVar status
        return (value == Connected || value == Bound || value == Listening)
isAcceptable (MkSocket _ AF_UNIX _ _ _) = return False

{-# LINE 1121 "Network/Socket.hsc" #-}
isAcceptable (MkSocket _ _ _ _ status) = do
    value <- readMVar status
    return (value == Connected || value == Listening)

-- -----------------------------------------------------------------------------
-- Internet address manipulation routines:

inet_addr :: String -> IO HostAddress
inet_addr ipstr = do
   withCString ipstr $ \str -> do
   had <- c_inet_addr str
   if had == -1
    then ioError (userError ("inet_addr: Malformed address: " ++ ipstr))
    else return had  -- network byte order

inet_ntoa :: HostAddress -> IO String
inet_ntoa haddr = do
  pstr <- c_inet_ntoa haddr
  peekCString pstr

-- | Turns a Socket into an 'Handle'. By default, the new handle is
-- unbuffered. Use 'System.IO.hSetBuffering' to change the buffering.
--
-- Note that since a 'Handle' is automatically closed by a finalizer
-- when it is no longer referenced, you should avoid doing any more
-- operations on the 'Socket' after calling 'socketToHandle'.  To
-- close the 'Socket' after 'socketToHandle', call 'System.IO.hClose'
-- on the 'Handle'.

socketToHandle :: Socket -> IOMode -> IO Handle
socketToHandle s@(MkSocket fd _ _ _ socketStatus) mode = do
 modifyMVar socketStatus $ \ status ->
    if status == ConvertedToHandle
        then ioError (userError ("socketToHandle: already a Handle"))
        else do
    h <- fdToHandle' (fromIntegral fd) (Just GHC.IO.Device.Stream) True (show s) mode True{-bin-}
    hSetBuffering h NoBuffering
    return (ConvertedToHandle, h)

-- | Pack a list of values into a bitmask.  The possible mappings from
-- value to bit-to-set are given as the first argument.  We assume
-- that each value can cause exactly one bit to be set; unpackBits will
-- break if this property is not true.

packBits :: (Eq a, Num b, Bits b) => [(a, b)] -> [a] -> b

packBits mapping xs = foldl' pack 0 mapping
    where pack acc (k, v) | k `elem` xs = acc .|. v
                          | otherwise   = acc

-- | Unpack a bitmask into a list of values.

unpackBits :: (Num b, Bits b) => [(a, b)] -> b -> [a]

-- Be permissive and ignore unknown bit values. At least on OS X,
-- getaddrinfo returns an ai_flags field with bits set that have no
-- entry in <netdb.h>.
unpackBits [] _    = []
unpackBits ((k,v):xs) r
    | r .&. v /= 0 = k : unpackBits xs (r .&. complement v)
    | otherwise    = unpackBits xs r

-----------------------------------------------------------------------------
-- Address and service lookups


{-# LINE 1187 "Network/Socket.hsc" #-}

-- | Flags that control the querying behaviour of 'getAddrInfo'.
data AddrInfoFlag
    = AI_ADDRCONFIG
    | AI_ALL
    | AI_CANONNAME
    | AI_NUMERICHOST
    | AI_NUMERICSERV
    | AI_PASSIVE
    | AI_V4MAPPED
    deriving (Eq, Read, Show, Typeable)

aiFlagMapping :: [(AddrInfoFlag, CInt)]

aiFlagMapping =
    [

{-# LINE 1204 "Network/Socket.hsc" #-}
     (AI_ADDRCONFIG, 32),
{-# LINE 1205 "Network/Socket.hsc" #-}

{-# LINE 1208 "Network/Socket.hsc" #-}

{-# LINE 1209 "Network/Socket.hsc" #-}
     (AI_ALL, 16),
{-# LINE 1210 "Network/Socket.hsc" #-}

{-# LINE 1213 "Network/Socket.hsc" #-}
     (AI_CANONNAME, 2),
{-# LINE 1214 "Network/Socket.hsc" #-}
     (AI_NUMERICHOST, 4),
{-# LINE 1215 "Network/Socket.hsc" #-}

{-# LINE 1216 "Network/Socket.hsc" #-}
     (AI_NUMERICSERV, 1024),
{-# LINE 1217 "Network/Socket.hsc" #-}

{-# LINE 1220 "Network/Socket.hsc" #-}
     (AI_PASSIVE, 1),
{-# LINE 1221 "Network/Socket.hsc" #-}

{-# LINE 1222 "Network/Socket.hsc" #-}
     (AI_V4MAPPED, 8)
{-# LINE 1223 "Network/Socket.hsc" #-}

{-# LINE 1226 "Network/Socket.hsc" #-}
    ]

-- | Indicate whether the given 'AddrInfoFlag' will have any effect on
-- this system.
addrInfoFlagImplemented :: AddrInfoFlag -> Bool
addrInfoFlagImplemented f = packBits aiFlagMapping [f] /= 0

data AddrInfo =
    AddrInfo {
        addrFlags :: [AddrInfoFlag],
        addrFamily :: Family,
        addrSocketType :: SocketType,
        addrProtocol :: ProtocolNumber,
        addrAddress :: SockAddr,
        addrCanonName :: Maybe String
        }
    deriving (Eq, Show, Typeable)

instance Storable AddrInfo where
    sizeOf    _ = 48
{-# LINE 1246 "Network/Socket.hsc" #-}
    alignment _ = alignment (undefined :: CInt)

    peek p = do
        ai_flags <- ((\hsc_ptr -> peekByteOff hsc_ptr 0)) p
{-# LINE 1250 "Network/Socket.hsc" #-}
        ai_family <- ((\hsc_ptr -> peekByteOff hsc_ptr 4)) p
{-# LINE 1251 "Network/Socket.hsc" #-}
        ai_socktype <- ((\hsc_ptr -> peekByteOff hsc_ptr 8)) p
{-# LINE 1252 "Network/Socket.hsc" #-}
        ai_protocol <- ((\hsc_ptr -> peekByteOff hsc_ptr 12)) p
{-# LINE 1253 "Network/Socket.hsc" #-}
        ai_addr <- ((\hsc_ptr -> peekByteOff hsc_ptr 24)) p >>= peekSockAddr
{-# LINE 1254 "Network/Socket.hsc" #-}
        ai_canonname_ptr <- ((\hsc_ptr -> peekByteOff hsc_ptr 32)) p
{-# LINE 1255 "Network/Socket.hsc" #-}

        ai_canonname <- if ai_canonname_ptr == nullPtr
                        then return Nothing
                        else liftM Just $ peekCString ai_canonname_ptr

        socktype <- unpackSocketType' "AddrInfo.peek" ai_socktype
        return (AddrInfo
                {
                 addrFlags = unpackBits aiFlagMapping ai_flags,
                 addrFamily = unpackFamily ai_family,
                 addrSocketType = socktype,
                 addrProtocol = ai_protocol,
                 addrAddress = ai_addr,
                 addrCanonName = ai_canonname
                })

    poke p (AddrInfo flags family socketType protocol _ _) = do
        c_stype <- packSocketTypeOrThrow "AddrInfo.poke" socketType

        ((\hsc_ptr -> pokeByteOff hsc_ptr 0)) p (packBits aiFlagMapping flags)
{-# LINE 1275 "Network/Socket.hsc" #-}
        ((\hsc_ptr -> pokeByteOff hsc_ptr 4)) p (packFamily family)
{-# LINE 1276 "Network/Socket.hsc" #-}
        ((\hsc_ptr -> pokeByteOff hsc_ptr 8)) p c_stype
{-# LINE 1277 "Network/Socket.hsc" #-}
        ((\hsc_ptr -> pokeByteOff hsc_ptr 12)) p protocol
{-# LINE 1278 "Network/Socket.hsc" #-}

        -- stuff below is probably not needed, but let's zero it for safety

        ((\hsc_ptr -> pokeByteOff hsc_ptr 16)) p (0::CSize)
{-# LINE 1282 "Network/Socket.hsc" #-}
        ((\hsc_ptr -> pokeByteOff hsc_ptr 24)) p nullPtr
{-# LINE 1283 "Network/Socket.hsc" #-}
        ((\hsc_ptr -> pokeByteOff hsc_ptr 32)) p nullPtr
{-# LINE 1284 "Network/Socket.hsc" #-}
        ((\hsc_ptr -> pokeByteOff hsc_ptr 40)) p nullPtr
{-# LINE 1285 "Network/Socket.hsc" #-}

data NameInfoFlag
    = NI_DGRAM
    | NI_NAMEREQD
    | NI_NOFQDN
    | NI_NUMERICHOST
    | NI_NUMERICSERV
    deriving (Eq, Read, Show, Typeable)

niFlagMapping :: [(NameInfoFlag, CInt)]

niFlagMapping = [(NI_DGRAM, 16),
{-# LINE 1297 "Network/Socket.hsc" #-}
                 (NI_NAMEREQD, 8),
{-# LINE 1298 "Network/Socket.hsc" #-}
                 (NI_NOFQDN, 4),
{-# LINE 1299 "Network/Socket.hsc" #-}
                 (NI_NUMERICHOST, 1),
{-# LINE 1300 "Network/Socket.hsc" #-}
                 (NI_NUMERICSERV, 2)]
{-# LINE 1301 "Network/Socket.hsc" #-}

-- | Default hints for address lookup with 'getAddrInfo'.  The values
-- of the 'addrAddress' and 'addrCanonName' fields are 'undefined',
-- and are never inspected by 'getAddrInfo'.

defaultHints :: AddrInfo

defaultHints = AddrInfo {
                         addrFlags = [],
                         addrFamily = AF_UNSPEC,
                         addrSocketType = NoSocketType,
                         addrProtocol = defaultProtocol,
                         addrAddress = undefined,
                         addrCanonName = undefined
                        }

-- | Resolve a host or service name to one or more addresses.
-- The 'AddrInfo' values that this function returns contain 'SockAddr'
-- values that you can pass directly to 'connect' or
-- 'bind'.
--
-- This function is protocol independent.  It can return both IPv4 and
-- IPv6 address information.
--
-- The 'AddrInfo' argument specifies the preferred query behaviour,
-- socket options, or protocol.  You can override these conveniently
-- using Haskell's record update syntax on 'defaultHints', for example
-- as follows:
--
-- @
--   myHints = defaultHints { addrFlags = [AI_ADDRCONFIG, AI_CANONNAME] }
-- @
--
-- Values for 'addrFlags' control query behaviour.  The supported
-- flags are as follows:
--
--   [@AI_PASSIVE@] If no 'HostName' value is provided, the network
--     address in each 'SockAddr'
--     will be left as a "wild card", i.e. as either 'iNADDR_ANY'
--     or 'iN6ADDR_ANY'.  This is useful for server applications that
--     will accept connections from any client.
--
--   [@AI_CANONNAME@] The 'addrCanonName' field of the first returned
--     'AddrInfo' will contain the "canonical name" of the host.
--
--   [@AI_NUMERICHOST@] The 'HostName' argument /must/ be a numeric
--     address in string form, and network name lookups will not be
--     attempted.
--
-- /Note/: Although the following flags are required by RFC 3493, they
-- may not have an effect on all platforms, because the underlying
-- network stack may not support them.  To see whether a flag from the
-- list below will have any effect, call 'addrInfoFlagImplemented'.
--
--   [@AI_NUMERICSERV@] The 'ServiceName' argument /must/ be a port
--     number in string form, and service name lookups will not be
--     attempted.
--
--   [@AI_ADDRCONFIG@] The list of returned 'AddrInfo' values will
--     only contain IPv4 addresses if the local system has at least
--     one IPv4 interface configured, and likewise for IPv6.
--
--   [@AI_V4MAPPED@] If an IPv6 lookup is performed, and no IPv6
--     addresses are found, IPv6-mapped IPv4 addresses will be
--     returned.
--
--   [@AI_ALL@] If 'AI_ALL' is specified, return all matching IPv6 and
--     IPv4 addresses.  Otherwise, this flag has no effect.
--
-- You must provide a 'Just' value for at least one of the 'HostName'
-- or 'ServiceName' arguments.  'HostName' can be either a numeric
-- network address (dotted quad for IPv4, colon-separated hex for
-- IPv6) or a hostname.  In the latter case, its addresses will be
-- looked up unless 'AI_NUMERICHOST' is specified as a hint.  If you
-- do not provide a 'HostName' value /and/ do not set 'AI_PASSIVE' as
-- a hint, network addresses in the result will contain the address of
-- the loopback interface.
--
-- If the query fails, this function throws an IO exception instead of
-- returning an empty list.  Otherwise, it returns a non-empty list
-- of 'AddrInfo' values.
--
-- There are several reasons why a query might result in several
-- values.  For example, the queried-for host could be multihomed, or
-- the service might be available via several protocols.
--
-- Note: the order of arguments is slightly different to that defined
-- for @getaddrinfo@ in RFC 2553.  The 'AddrInfo' parameter comes first
-- to make partial application easier.
--
-- Example:
-- @
--   let hints = defaultHints { addrFlags = [AI_ADDRCONFIG, AI_CANONNAME] }
--   addrs <- getAddrInfo (Just hints) (Just "www.haskell.org") (Just "http")
--   let addr = head addrs
--   sock <- socket (addrFamily addr) (addrSocketType addr) (addrProtocol addr)
--   connect sock (addrAddress addr)
-- @

getAddrInfo :: Maybe AddrInfo -- ^ preferred socket type or protocol
            -> Maybe HostName -- ^ host name to look up
            -> Maybe ServiceName -- ^ service name to look up
            -> IO [AddrInfo] -- ^ resolved addresses, with "best" first

getAddrInfo hints node service =
  maybeWith withCString node $ \c_node ->
    maybeWith withCString service $ \c_service ->
      maybeWith with filteredHints $ \c_hints ->
        alloca $ \ptr_ptr_addrs -> do
          ret <- c_getaddrinfo c_node c_service c_hints ptr_ptr_addrs
          case ret of
            0 -> do ptr_addrs <- peek ptr_ptr_addrs
                    ais <- followAddrInfo ptr_addrs
                    c_freeaddrinfo ptr_addrs
                    return ais
            _ -> do err <- gai_strerror ret
                    ioError (ioeSetErrorString
                             (mkIOError NoSuchThing "getAddrInfo" Nothing
                              Nothing) err)
    -- Leaving out the service and using AI_NUMERICSERV causes a
    -- segfault on OS X 10.8.2. This code removes AI_NUMERICSERV
    -- (which has no effect) in that case.
  where

{-# LINE 1429 "Network/Socket.hsc" #-}
    filteredHints = hints

{-# LINE 1431 "Network/Socket.hsc" #-}

followAddrInfo :: Ptr AddrInfo -> IO [AddrInfo]

followAddrInfo ptr_ai | ptr_ai == nullPtr = return []
                      | otherwise = do
    a <- peek ptr_ai
    as <- ((\hsc_ptr -> peekByteOff hsc_ptr 40)) ptr_ai >>= followAddrInfo
{-# LINE 1438 "Network/Socket.hsc" #-}
    return (a:as)

foreign import ccall safe "hsnet_getaddrinfo"
    c_getaddrinfo :: CString -> CString -> Ptr AddrInfo -> Ptr (Ptr AddrInfo)
                  -> IO CInt

foreign import ccall safe "hsnet_freeaddrinfo"
    c_freeaddrinfo :: Ptr AddrInfo -> IO ()

gai_strerror :: CInt -> IO String


{-# LINE 1450 "Network/Socket.hsc" #-}
gai_strerror n = c_gai_strerror n >>= peekCString

foreign import ccall safe "gai_strerror"
    c_gai_strerror :: CInt -> IO CString

{-# LINE 1457 "Network/Socket.hsc" #-}

withCStringIf :: Bool -> Int -> (CSize -> CString -> IO a) -> IO a
withCStringIf False _ f = f 0 nullPtr
withCStringIf True n f = allocaBytes n (f (fromIntegral n))

-- | Resolve an address to a host or service name.
-- This function is protocol independent.
--
-- The list of 'NameInfoFlag' values controls query behaviour.  The
-- supported flags are as follows:
--
--   [@NI_NOFQDN@] If a host is local, return only the
--     hostname part of the FQDN.
--
--   [@NI_NUMERICHOST@] The name of the host is not
--     looked up.  Instead, a numeric representation of the host's
--     address is returned.  For an IPv4 address, this will be a
--     dotted-quad string.  For IPv6, it will be colon-separated
--     hexadecimal.
--
--   [@NI_NUMERICSERV@] The name of the service is not
--     looked up.  Instead, a numeric representation of the
--     service is returned.
--
--   [@NI_NAMEREQD@] If the hostname cannot be looked up, an IO error
--     is thrown.
--
--   [@NI_DGRAM@] Resolve a datagram-based service name.  This is
--     required only for the few protocols that have different port
--     numbers for their datagram-based versions than for their
--     stream-based versions.
--
-- Hostname and service name lookups can be expensive.  You can
-- specify which lookups to perform via the two 'Bool' arguments.  If
-- one of these is 'False', the corresponding value in the returned
-- tuple will be 'Nothing', and no lookup will be performed.
--
-- If a host or service's name cannot be looked up, then the numeric
-- form of the address or service will be returned.
--
-- If the query fails, this function throws an IO exception.
--
-- Example:
-- @
--   (hostName, _) <- getNameInfo [] True False myAddress
-- @

getNameInfo :: [NameInfoFlag] -- ^ flags to control lookup behaviour
            -> Bool -- ^ whether to look up a hostname
            -> Bool -- ^ whether to look up a service name
            -> SockAddr -- ^ the address to look up
            -> IO (Maybe HostName, Maybe ServiceName)

getNameInfo flags doHost doService addr =
  withCStringIf doHost (1025) $ \c_hostlen c_host ->
{-# LINE 1512 "Network/Socket.hsc" #-}
    withCStringIf doService (32) $ \c_servlen c_serv -> do
{-# LINE 1513 "Network/Socket.hsc" #-}
      withSockAddr addr $ \ptr_addr sz -> do
        ret <- c_getnameinfo ptr_addr (fromIntegral sz) c_host c_hostlen
                             c_serv c_servlen (packBits niFlagMapping flags)
        case ret of
          0 -> do
            let peekIf doIf c_val = if doIf
                                     then liftM Just $ peekCString c_val
                                     else return Nothing
            host <- peekIf doHost c_host
            serv <- peekIf doService c_serv
            return (host, serv)
          _ -> do err <- gai_strerror ret
                  ioError (ioeSetErrorString
                           (mkIOError NoSuchThing "getNameInfo" Nothing
                            Nothing) err)

foreign import ccall safe "hsnet_getnameinfo"
    c_getnameinfo :: Ptr SockAddr -> CInt{-CSockLen???-} -> CString -> CSize -> CString
                  -> CSize -> CInt -> IO CInt

{-# LINE 1533 "Network/Socket.hsc" #-}

mkInvalidRecvArgError :: String -> IOError
mkInvalidRecvArgError loc = ioeSetErrorString (mkIOError
                                    InvalidArgument
                                    loc Nothing Nothing) "non-positive length"

mkEOFError :: String -> IOError
mkEOFError loc = ioeSetErrorString (mkIOError EOF loc Nothing Nothing) "end of file"

-- ---------------------------------------------------------------------------
-- foreign imports from the C library

foreign import ccall unsafe "my_inet_ntoa"
  c_inet_ntoa :: HostAddress -> IO (Ptr CChar)

foreign import CALLCONV unsafe "inet_addr"
  c_inet_addr :: Ptr CChar -> IO HostAddress

foreign import CALLCONV unsafe "shutdown"
  c_shutdown :: CInt -> CInt -> IO CInt

closeFd :: CInt -> IO ()
closeFd fd = throwSocketErrorIfMinus1_ "Network.Socket.close" $ c_close fd


{-# LINE 1558 "Network/Socket.hsc" #-}
foreign import ccall unsafe "close"
  c_close :: CInt -> IO CInt

{-# LINE 1564 "Network/Socket.hsc" #-}

foreign import CALLCONV unsafe "socket"
  c_socket :: CInt -> CInt -> CInt -> IO CInt
foreign import CALLCONV unsafe "bind"
  c_bind :: CInt -> Ptr SockAddr -> CInt{-CSockLen???-} -> IO CInt
foreign import CALLCONV SAFE_ON_WIN "connect"
  c_connect :: CInt -> Ptr SockAddr -> CInt{-CSockLen???-} -> IO CInt
foreign import CALLCONV unsafe "accept"
  c_accept :: CInt -> Ptr SockAddr -> Ptr CInt{-CSockLen???-} -> IO CInt

{-# LINE 1574 "Network/Socket.hsc" #-}
foreign import CALLCONV unsafe "accept4"
  c_accept4 :: CInt -> Ptr SockAddr -> Ptr CInt{-CSockLen???-} -> CInt -> IO CInt

{-# LINE 1577 "Network/Socket.hsc" #-}
foreign import CALLCONV unsafe "listen"
  c_listen :: CInt -> CInt -> IO CInt


{-# LINE 1586 "Network/Socket.hsc" #-}

foreign import CALLCONV unsafe "send"
  c_send :: CInt -> Ptr a -> CSize -> CInt -> IO CInt
foreign import CALLCONV SAFE_ON_WIN "sendto"
  c_sendto :: CInt -> Ptr a -> CSize -> CInt -> Ptr SockAddr -> CInt -> IO CInt
foreign import CALLCONV unsafe "recv"
  c_recv :: CInt -> Ptr CChar -> CSize -> CInt -> IO CInt
foreign import CALLCONV SAFE_ON_WIN "recvfrom"
  c_recvfrom :: CInt -> Ptr a -> CSize -> CInt -> Ptr SockAddr -> Ptr CInt -> IO CInt
foreign import CALLCONV unsafe "getpeername"
  c_getpeername :: CInt -> Ptr SockAddr -> Ptr CInt -> IO CInt
foreign import CALLCONV unsafe "getsockname"
  c_getsockname :: CInt -> Ptr SockAddr -> Ptr CInt -> IO CInt

foreign import CALLCONV unsafe "getsockopt"
  c_getsockopt :: CInt -> CInt -> CInt -> Ptr CInt -> Ptr CInt -> IO CInt
foreign import CALLCONV unsafe "setsockopt"
  c_setsockopt :: CInt -> CInt -> CInt -> Ptr CInt -> CInt -> IO CInt


{-# LINE 1609 "Network/Socket.hsc" #-}
-- ---------------------------------------------------------------------------
-- * Deprecated aliases

-- $deprecated-aliases
--
-- These aliases are deprecated and should not be used in new code.
-- They will be removed in some future version of the package.

-- | Deprecated alias for 'bind'.
bindSocket :: Socket    -- Unconnected Socket
           -> SockAddr  -- Address to Bind to
           -> IO ()
bindSocket = bind

-- | Deprecated alias for 'close'.
sClose :: Socket -> IO ()
sClose = close

-- | Deprecated alias for 'isConnected'.
sIsConnected :: Socket -> IO Bool
sIsConnected = isConnected

-- | Deprecated alias for 'isBound'.
sIsBound :: Socket -> IO Bool
sIsBound = isBound

-- | Deprecated alias for 'isListening'.
sIsListening :: Socket -> IO Bool
sIsListening = isListening

-- | Deprecated alias for 'isReadable'.
sIsReadable  :: Socket -> IO Bool
sIsReadable = isReadable

-- | Deprecated alias for 'isWritable'.
sIsWritable  :: Socket -> IO Bool
sIsWritable = isWritable