{-# LINE 1 "libraries/unix/System/Posix/SharedMem.hsc" #-} {-# LINE 2 "libraries/unix/System/Posix/SharedMem.hsc" #-} {-# LANGUAGE Safe #-} {-# LINE 6 "libraries/unix/System/Posix/SharedMem.hsc" #-} ----------------------------------------------------------------------------- -- | -- Module : System.Posix.SharedMem -- Copyright : (c) Daniel Franke 2007 -- License : BSD-style (see the file libraries/base/LICENSE) -- -- Maintainer : libraries@haskell.org -- Stability : experimental -- Portability : non-portable (requires POSIX) -- -- POSIX shared memory support. -- ----------------------------------------------------------------------------- module System.Posix.SharedMem (ShmOpenFlags(..), shmOpen, shmUnlink) where import System.Posix.Types {-# LINE 32 "libraries/unix/System/Posix/SharedMem.hsc" #-} import Foreign.C {-# LINE 34 "libraries/unix/System/Posix/SharedMem.hsc" #-} {-# LINE 35 "libraries/unix/System/Posix/SharedMem.hsc" #-} import Data.Bits {-# LINE 37 "libraries/unix/System/Posix/SharedMem.hsc" #-} data ShmOpenFlags = ShmOpenFlags { shmReadWrite :: Bool, -- ^ If true, open the shm object read-write rather than read-only. shmCreate :: Bool, -- ^ If true, create the shm object if it does not exist. shmExclusive :: Bool, -- ^ If true, throw an exception if the shm object already exists. shmTrunc :: Bool -- ^ If true, wipe the contents of the shm object after opening it. } -- | Open a shared memory object with the given name, flags, and mode. shmOpen :: String -> ShmOpenFlags -> FileMode -> IO Fd {-# LINE 52 "libraries/unix/System/Posix/SharedMem.hsc" #-} shmOpen name flags mode = do cflags0 <- return 0 cflags1 <- return $ cflags0 .|. (if shmReadWrite flags then 2 {-# LINE 56 "libraries/unix/System/Posix/SharedMem.hsc" #-} else 0) {-# LINE 57 "libraries/unix/System/Posix/SharedMem.hsc" #-} cflags2 <- return $ cflags1 .|. (if shmCreate flags then 64 {-# LINE 58 "libraries/unix/System/Posix/SharedMem.hsc" #-} else 0) cflags3 <- return $ cflags2 .|. (if shmExclusive flags then 128 {-# LINE 61 "libraries/unix/System/Posix/SharedMem.hsc" #-} else 0) cflags4 <- return $ cflags3 .|. (if shmTrunc flags then 512 {-# LINE 63 "libraries/unix/System/Posix/SharedMem.hsc" #-} else 0) withCAString name (shmOpen' cflags4) where shmOpen' cflags cname = do fd <- throwErrnoIfMinus1 "shmOpen" $ shm_open cname cflags mode return $ Fd fd {-# LINE 72 "libraries/unix/System/Posix/SharedMem.hsc" #-} -- | Delete the shared memory object with the given name. shmUnlink :: String -> IO () {-# LINE 76 "libraries/unix/System/Posix/SharedMem.hsc" #-} shmUnlink name = withCAString name shmUnlink' where shmUnlink' cname = throwErrnoIfMinus1_ "shmUnlink" $ shm_unlink cname {-# LINE 82 "libraries/unix/System/Posix/SharedMem.hsc" #-} {-# LINE 84 "libraries/unix/System/Posix/SharedMem.hsc" #-} foreign import ccall unsafe "shm_open" shm_open :: CString -> CInt -> CMode -> IO CInt {-# LINE 87 "libraries/unix/System/Posix/SharedMem.hsc" #-} {-# LINE 89 "libraries/unix/System/Posix/SharedMem.hsc" #-} foreign import ccall unsafe "shm_unlink" shm_unlink :: CString -> IO CInt {-# LINE 92 "libraries/unix/System/Posix/SharedMem.hsc" #-}