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|
module Network.HostName (
HostName, getHostName
) where
import Foreign.C.Error
import Foreign.C.String
import Foreign.C.Types
import Foreign.Marshal.Array
#ifdef WINDOWS
import Foreign.Marshal.Utils
import Foreign.Ptr
import Foreign.Storable
import System.Win32.Types
foreign import stdcall unsafe "windows.h GetComputerNameExW" getComputerNameEx :: COMPUTER_NAME_FORMAT -> LPTSTR -> LPDWORD -> IO BOOL
type COMPUTER_NAME_FORMAT = CInt
computerNamePhysicalDnsHostname :: COMPUTER_NAME_FORMAT
computerNamePhysicalDnsHostname = 5
getHostName :: IO HostName
getHostName = with 0 $ \p_charcount -> do
-- On the first run, determine the character count and ignore any error we get
_ <- getComputerNameEx computerNamePhysicalDnsHostname nullPtr p_charcount
charcount <- peek p_charcount
-- The second time around, use the correct character count to retrieve the data
withTString (replicate (fromIntegral charcount) ' ') $ \name -> do
failIfFalse_ "GetComputerNameExW" $ getComputerNameEx computerNamePhysicalDnsHostname name p_charcount
peekTString name
#else
foreign import ccall unsafe "gethostname" gethostname :: CString -> CSize -> IO CInt
getHostName :: IO HostName
getHostName = allocaArray0 size $ \cstr -> do
throwErrnoIfMinus1_ "getHostName" $ gethostname cstr (fromIntegral size)
peekCString cstr
where size = 256
#endif
type HostName = String
|
