network-3.1.1.0: Network/Socket/Buffer.hsc
{-# LANGUAGE CPP #-}
##include "HsNetDef.h"
#if defined(mingw32_HOST_OS)
# include "windows.h"
#endif
module Network.Socket.Buffer (
sendBufTo
, sendBuf
, recvBufFrom
, recvBuf
, recvBufNoWait
) where
#if !defined(mingw32_HOST_OS)
import Foreign.C.Error (getErrno, eAGAIN, eWOULDBLOCK)
#endif
import Foreign.Marshal.Alloc (alloca)
import GHC.IO.Exception (IOErrorType(InvalidArgument))
import System.IO.Error (mkIOError, ioeSetErrorString, catchIOError)
#if defined(mingw32_HOST_OS)
import GHC.IO.FD (FD(..), readRawBufferPtr, writeRawBufferPtr)
#endif
import Network.Socket.Imports
import Network.Socket.Internal
import Network.Socket.Name
import Network.Socket.Types
-- | 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 :: SocketAddress sa =>
Socket -- (possibly) bound/connected Socket
-> Ptr a
-> Int -- Data to send
-> sa
-> IO Int -- Number of Bytes sent
sendBufTo s ptr nbytes sa =
withSocketAddress sa $ \p_sa siz -> fromIntegral <$> do
withFdSocket s $ \fd -> do
let sz = fromIntegral siz
n = fromIntegral nbytes
flags = 0
throwSocketErrorWaitWrite s "Network.Socket.sendBufTo" $
c_sendto fd ptr n flags p_sa sz
#if defined(mingw32_HOST_OS)
socket2FD :: Socket -> IO FD
socket2FD s = do
fd <- unsafeFdSocket s
-- HACK, 1 means True
return $ FD{ fdFD = fd, fdIsSocket_ = 1 }
#endif
-- | 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 s str len = fromIntegral <$> do
#if defined(mingw32_HOST_OS)
-- writeRawBufferPtr is supposed to handle checking for errors, but it's broken
-- on x86_64 because of GHC bug #12010 so we duplicate the check here. The call
-- to throwSocketErrorIfMinus1Retry can be removed when no GHC version with the
-- bug is supported.
fd <- socket2FD s
let clen = fromIntegral len
throwSocketErrorIfMinus1Retry "Network.Socket.sendBuf" $
writeRawBufferPtr "Network.Socket.sendBuf" fd (castPtr str) 0 clen
#else
withFdSocket s $ \fd -> do
let flags = 0
clen = fromIntegral len
throwSocketErrorWaitWrite s "Network.Socket.sendBuf" $
c_send fd str clen flags
#endif
-- | 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.
--
-- If the first return value is zero, it means EOF.
--
-- For 'Stream' sockets, the second return value would be invalid.
--
-- NOTE: blocking on Windows unless you compile with -threaded (see
-- GHC ticket #1129)
recvBufFrom :: SocketAddress sa => Socket -> Ptr a -> Int -> IO (Int, sa)
recvBufFrom s ptr nbytes
| nbytes <= 0 = ioError (mkInvalidRecvArgError "Network.Socket.recvBufFrom")
| otherwise = withNewSocketAddress $ \ptr_sa sz -> alloca $ \ptr_len ->
withFdSocket s $ \fd -> do
poke ptr_len (fromIntegral sz)
let cnbytes = fromIntegral nbytes
flags = 0
len <- throwSocketErrorWaitRead s "Network.Socket.recvBufFrom" $
c_recvfrom fd ptr cnbytes flags ptr_sa ptr_len
sockaddr <- peekSocketAddress ptr_sa
`catchIOError` \_ -> getPeerName s
return (fromIntegral len, sockaddr)
-- | 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.
--
-- The return value is the length of received data. Zero means
-- EOF. Historical note: Version 2.8.x.y or earlier,
-- an EOF error was thrown. This was changed in version 3.0.
recvBuf :: Socket -> Ptr Word8 -> Int -> IO Int
recvBuf s ptr nbytes
| nbytes <= 0 = ioError (mkInvalidRecvArgError "Network.Socket.recvBuf")
| otherwise = do
#if defined(mingw32_HOST_OS)
-- see comment in sendBuf above.
fd <- socket2FD s
let cnbytes = fromIntegral nbytes
len <- throwSocketErrorIfMinus1Retry "Network.Socket.recvBuf" $
readRawBufferPtr "Network.Socket.recvBuf" fd ptr 0 cnbytes
#else
len <- withFdSocket s $ \fd ->
throwSocketErrorWaitRead s "Network.Socket.recvBuf" $
c_recv fd (castPtr ptr) (fromIntegral nbytes) 0{-flags-}
#endif
return $ fromIntegral len
-- | Receive data from the socket. This function returns immediately
-- even if data is not available. In other words, IO manager is NOT
-- involved. The length of data is returned if received.
-- -1 is returned in the case of EAGAIN or EWOULDBLOCK.
-- -2 is returned in other error cases.
recvBufNoWait :: Socket -> Ptr Word8 -> Int -> IO Int
recvBufNoWait s ptr nbytes = withFdSocket s $ \fd -> do
#if defined(mingw32_HOST_OS)
alloca $ \ptr_bytes -> do
res <- c_ioctlsocket fd #{const FIONREAD} ptr_bytes
avail <- peek ptr_bytes
r <- if res == #{const NO_ERROR} && avail > 0 then
c_recv fd (castPtr ptr) (fromIntegral nbytes) 0{-flags-}
else if avail == 0 then
-- Socket would block, could also mean socket is closed but
-- can't distinguish
return (-1)
else do err <- c_WSAGetLastError
if err == #{const WSAEWOULDBLOCK}
|| err == #{const WSAEINPROGRESS} then
return (-1)
else
return (-2)
return $ fromIntegral r
#else
r <- c_recv fd (castPtr ptr) (fromIntegral nbytes) 0{-flags-}
if r >= 0 then
return $ fromIntegral r
else do
err <- getErrno
if err == eAGAIN || err == eWOULDBLOCK then
return (-1)
else
return (-2)
#endif
mkInvalidRecvArgError :: String -> IOError
mkInvalidRecvArgError loc = ioeSetErrorString (mkIOError
InvalidArgument
loc Nothing Nothing) "non-positive length"
#if !defined(mingw32_HOST_OS)
foreign import ccall unsafe "send"
c_send :: CInt -> Ptr a -> CSize -> CInt -> IO CInt
#else
foreign import CALLCONV SAFE_ON_WIN "ioctlsocket"
c_ioctlsocket :: CInt -> CLong -> Ptr CULong -> IO CInt
foreign import CALLCONV SAFE_ON_WIN "WSAGetLastError"
c_WSAGetLastError :: IO CInt
#endif
foreign import ccall unsafe "recv"
c_recv :: CInt -> Ptr CChar -> CSize -> CInt -> IO CInt
foreign import CALLCONV SAFE_ON_WIN "sendto"
c_sendto :: CInt -> Ptr a -> CSize -> CInt -> Ptr sa -> CInt -> IO CInt
foreign import CALLCONV SAFE_ON_WIN "recvfrom"
c_recvfrom :: CInt -> Ptr a -> CSize -> CInt -> Ptr sa -> Ptr CInt -> IO CInt