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{-# LANGUAGE DeriveGeneric, GeneralizedNewtypeDeriving #-}
-----------------------------------------------------------------------------
-- |
-- Module : Data.Storable.Endian
-- Copyright : (c) Eugene Kirpichov 2010
-- License : New BSD
--
-- Maintainer : Eugene Kirpichov <ekirpichov@gmail.com>
-- Stability : experimental
-- Portability : portable
--
-- Storable instances with endianness.
--
module Data.Storable.Endian
(
LittleEndian(..), BigEndian(..),
HasLittleEndian(..), HasBigEndian(..)
)
where
import System.ByteOrder
import Foreign.Ptr
import Foreign.Storable
import Unsafe.Coerce
import Data.Bits
import Data.Word
#if defined(__GLASGOW_HASKELL__) && !defined(__HADDOCK__)
import GHC.Base
import GHC.Int
import GHC.Word
#endif
import GHC.Generics (Generic(..))
newtype LittleEndian a = LE { getLittleEndian :: a }
deriving ( Eq, Ord, Show, Read, Enum
, Num, Integral, Fractional, Floating, Real, RealFrac, RealFloat
, Generic)
newtype BigEndian a = BE { getBigEndian :: a }
deriving ( Eq, Ord, Show, Read, Enum
, Num, Integral, Fractional, Floating, Real, RealFrac, RealFloat
, Generic)
class HasLittleEndian a where
peekLE :: Ptr a -> IO a
pokeLE :: Ptr a -> a -> IO ()
class HasBigEndian a where
peekBE :: Ptr a -> IO a
pokeBE :: Ptr a -> a -> IO ()
instance (HasLittleEndian a, Storable a) => Storable (LittleEndian a) where
sizeOf (LE a) = sizeOf a
alignment (LE a) = alignment a
peek p = LE `fmap` peekLE (castPtr p)
poke p (LE a) = pokeLE (castPtr p) a
instance (HasBigEndian a, Storable a) => Storable (BigEndian a) where
sizeOf (BE a) = sizeOf a
alignment (BE a) = alignment a
peek p = BE `fmap` peekBE (castPtr p)
poke p (BE a) = pokeBE (castPtr p) a
fork f onX onY = \x y -> f (onX x) (onY y)
------------------------------
-- Little-endian instances
------------------------------
instance HasLittleEndian Int16 where
peekLE = unsafeCoerce . getWord16le . castPtr
pokeLE = fork putWord16le castPtr unsafeCoerce
instance HasLittleEndian Int32 where
peekLE = unsafeCoerce . getWord32le . castPtr
pokeLE = fork putWord32le castPtr unsafeCoerce
instance HasLittleEndian Int64 where
peekLE = unsafeCoerce . getWord64le . castPtr
pokeLE = fork putWord64le castPtr unsafeCoerce
instance HasLittleEndian Word16 where
peekLE = unsafeCoerce . getWord16le . castPtr
pokeLE = fork putWord16le castPtr unsafeCoerce
instance HasLittleEndian Word32 where
peekLE = unsafeCoerce . getWord32le . castPtr
pokeLE = fork putWord32le castPtr unsafeCoerce
instance HasLittleEndian Word64 where
peekLE = unsafeCoerce . getWord64le . castPtr
pokeLE = fork putWord64le castPtr unsafeCoerce
instance HasLittleEndian Float where
peekLE = unsafeCoerce . getWord32le . castPtr
pokeLE = fork putWord32le castPtr unsafeCoerce
instance HasLittleEndian Double where
peekLE = unsafeCoerce . getWord64le . castPtr
pokeLE = fork putWord64le castPtr unsafeCoerce
------------------------------
-- Big-endian instances
------------------------------
instance HasBigEndian Int16 where
peekBE = unsafeCoerce . getWord16be . castPtr
pokeBE = fork putWord16be castPtr unsafeCoerce
instance HasBigEndian Int32 where
peekBE = unsafeCoerce . getWord32be . castPtr
pokeBE = fork putWord32be castPtr unsafeCoerce
instance HasBigEndian Int64 where
peekBE = unsafeCoerce . getWord64be . castPtr
pokeBE = fork putWord64be castPtr unsafeCoerce
instance HasBigEndian Word16 where
peekBE = unsafeCoerce . getWord16be . castPtr
pokeBE = fork putWord16be castPtr unsafeCoerce
instance HasBigEndian Word32 where
peekBE = unsafeCoerce . getWord32be . castPtr
pokeBE = fork putWord32be castPtr unsafeCoerce
instance HasBigEndian Word64 where
peekBE = unsafeCoerce . getWord64be . castPtr
pokeBE = fork putWord64be castPtr unsafeCoerce
instance HasBigEndian Float where
peekBE = unsafeCoerce . getWord32be . castPtr
pokeBE = fork putWord32be castPtr unsafeCoerce
instance HasBigEndian Double where
peekBE = unsafeCoerce . getWord64be . castPtr
pokeBE = fork putWord64be castPtr unsafeCoerce
-- The code below has been adapted from the 'binary' library
-- http://hackage.haskell.org/package/binary
------------------------------------------------------------------------
--
-- We rely on the fromIntegral to do the right masking for us.
-- The inlining here is critical, and can be worth 4x performance
--
-- | Write a Word16 in big endian format
putWord16be :: Ptr Word8 -> Word16 -> IO ()
putWord16be = if byteOrder == BigEndian
then \p w -> poke (castPtr p) w
else \p w -> do
poke p (fromIntegral (shiftr_w16 w 8) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (w) :: Word8)
{-# INLINE putWord16be #-}
-- | Write a Word16 in little endian format
putWord16le :: Ptr Word8 -> Word16 -> IO ()
putWord16le = if byteOrder == LittleEndian
then \p w -> poke (castPtr p) w
else \p w -> do
poke p (fromIntegral (w) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (shiftr_w16 w 8) :: Word8)
{-# INLINE putWord16le #-}
-- putWord16le w16 = writeN 2 (\p -> poke (castPtr p) w16)
-- | Write a Word32 in big endian format
putWord32be :: Ptr Word8 -> Word32 -> IO ()
putWord32be = if byteOrder == BigEndian
then \p w -> poke (castPtr p) w
else \p w -> do
poke p (fromIntegral (shiftr_w32 w 24) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (shiftr_w32 w 16) :: Word8)
poke (p `plusPtr` 2) (fromIntegral (shiftr_w32 w 8) :: Word8)
poke (p `plusPtr` 3) (fromIntegral (w) :: Word8)
{-# INLINE putWord32be #-}
-- | Write a Word32 in little endian format
putWord32le :: Ptr Word8 -> Word32 -> IO ()
putWord32le = if byteOrder == LittleEndian
then \p w -> poke (castPtr p) w
else \p w -> do
poke p (fromIntegral (w) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (shiftr_w32 w 8) :: Word8)
poke (p `plusPtr` 2) (fromIntegral (shiftr_w32 w 16) :: Word8)
poke (p `plusPtr` 3) (fromIntegral (shiftr_w32 w 24) :: Word8)
{-# INLINE putWord32le #-}
-- | Write a Word64 in big endian format
putWord64be :: Ptr Word8 -> Word64 -> IO ()
putWord64be = if byteOrder == BigEndian
then \p w -> poke (castPtr p) w
else \p w -> do
#if WORD_SIZE_IN_BITS < 64
--
-- To avoid expensive 64 bit shifts on 32 bit machines, we cast to
-- Word32, and write that
--
let a = fromIntegral (shiftr_w64 w 32) :: Word32
b = fromIntegral w :: Word32
poke p (fromIntegral (shiftr_w32 a 24) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (shiftr_w32 a 16) :: Word8)
poke (p `plusPtr` 2) (fromIntegral (shiftr_w32 a 8) :: Word8)
poke (p `plusPtr` 3) (fromIntegral (a) :: Word8)
poke (p `plusPtr` 4) (fromIntegral (shiftr_w32 b 24) :: Word8)
poke (p `plusPtr` 5) (fromIntegral (shiftr_w32 b 16) :: Word8)
poke (p `plusPtr` 6) (fromIntegral (shiftr_w32 b 8) :: Word8)
poke (p `plusPtr` 7) (fromIntegral (b) :: Word8)
#else
poke p (fromIntegral (shiftr_w64 w 56) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (shiftr_w64 w 48) :: Word8)
poke (p `plusPtr` 2) (fromIntegral (shiftr_w64 w 40) :: Word8)
poke (p `plusPtr` 3) (fromIntegral (shiftr_w64 w 32) :: Word8)
poke (p `plusPtr` 4) (fromIntegral (shiftr_w64 w 24) :: Word8)
poke (p `plusPtr` 5) (fromIntegral (shiftr_w64 w 16) :: Word8)
poke (p `plusPtr` 6) (fromIntegral (shiftr_w64 w 8) :: Word8)
poke (p `plusPtr` 7) (fromIntegral (w) :: Word8)
#endif
{-# INLINE putWord64be #-}
-- | Write a Word64 in little endian format
putWord64le :: Ptr Word8 -> Word64 -> IO ()
putWord64le = if byteOrder == LittleEndian
then \p w -> poke (castPtr p) w
else \p w -> do
#if WORD_SIZE_IN_BITS < 64
let b = fromIntegral (shiftr_w64 w 32) :: Word32
a = fromIntegral w :: Word32
poke (p) (fromIntegral (a) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (shiftr_w32 a 8) :: Word8)
poke (p `plusPtr` 2) (fromIntegral (shiftr_w32 a 16) :: Word8)
poke (p `plusPtr` 3) (fromIntegral (shiftr_w32 a 24) :: Word8)
poke (p `plusPtr` 4) (fromIntegral (b) :: Word8)
poke (p `plusPtr` 5) (fromIntegral (shiftr_w32 b 8) :: Word8)
poke (p `plusPtr` 6) (fromIntegral (shiftr_w32 b 16) :: Word8)
poke (p `plusPtr` 7) (fromIntegral (shiftr_w32 b 24) :: Word8)
#else
poke p (fromIntegral (w) :: Word8)
poke (p `plusPtr` 1) (fromIntegral (shiftr_w64 w 8) :: Word8)
poke (p `plusPtr` 2) (fromIntegral (shiftr_w64 w 16) :: Word8)
poke (p `plusPtr` 3) (fromIntegral (shiftr_w64 w 24) :: Word8)
poke (p `plusPtr` 4) (fromIntegral (shiftr_w64 w 32) :: Word8)
poke (p `plusPtr` 5) (fromIntegral (shiftr_w64 w 40) :: Word8)
poke (p `plusPtr` 6) (fromIntegral (shiftr_w64 w 48) :: Word8)
poke (p `plusPtr` 7) (fromIntegral (shiftr_w64 w 56) :: Word8)
#endif
{-# INLINE putWord64le #-}
-- on a little endian machine:
-- putWord64le w64 = writeN 8 (\p -> poke (castPtr p) w64)
-- | Read a Word16 in big endian format
getWord16be :: Ptr Word8 -> IO Word16
getWord16be = if byteOrder == BigEndian
then \p -> peek (castPtr p)
else \p -> do
b0 <- fromIntegral `fmap` (p `peekElemOff` 0)
b1 <- fromIntegral `fmap` (p `peekElemOff` 1)
return $! (b0 `shiftl_w16` 8) .|.
(b1 )
{-# INLINE getWord16be #-}
-- | Read a Word16 in little endian format
getWord16le :: Ptr Word8 -> IO Word16
getWord16le = if byteOrder == LittleEndian
then \p -> peek (castPtr p)
else \p -> do
b0 <- fromIntegral `fmap` (p `peekElemOff` 0)
b1 <- fromIntegral `fmap` (p `peekElemOff` 1)
return $! (b1 `shiftl_w16` 8) .|.
(b0 )
{-# INLINE getWord16le #-}
-- | Read a Word32 in big endian format
getWord32be :: Ptr Word8 -> IO Word32
getWord32be = if byteOrder == BigEndian
then \p -> peek (castPtr p)
else \p -> do
b0 <- fromIntegral `fmap` (p `peekElemOff` 0)
b1 <- fromIntegral `fmap` (p `peekElemOff` 1)
b2 <- fromIntegral `fmap` (p `peekElemOff` 2)
b3 <- fromIntegral `fmap` (p `peekElemOff` 3)
return $! (b0 `shiftl_w32` 24) .|.
(b1 `shiftl_w32` 16) .|.
(b2 `shiftl_w32` 8) .|.
(b3 )
{-# INLINE getWord32be #-}
-- | Read a Word32 in little endian format
getWord32le :: Ptr Word8 -> IO Word32
getWord32le = if byteOrder == LittleEndian
then \p -> peek (castPtr p)
else \p -> do
b0 <- fromIntegral `fmap` (p `peekElemOff` 0)
b1 <- fromIntegral `fmap` (p `peekElemOff` 1)
b2 <- fromIntegral `fmap` (p `peekElemOff` 2)
b3 <- fromIntegral `fmap` (p `peekElemOff` 3)
return $! (b3 `shiftl_w32` 24) .|.
(b2 `shiftl_w32` 16) .|.
(b1 `shiftl_w32` 8) .|.
(b0 )
{-# INLINE getWord32le #-}
-- | Read a Word64 in big endian format
getWord64be :: Ptr Word8 -> IO Word64
getWord64be = if byteOrder == BigEndian
then \p -> peek (castPtr p)
else \p -> do
b0 <- fromIntegral `fmap` (p `peekElemOff` 0)
b1 <- fromIntegral `fmap` (p `peekElemOff` 1)
b2 <- fromIntegral `fmap` (p `peekElemOff` 2)
b3 <- fromIntegral `fmap` (p `peekElemOff` 3)
b4 <- fromIntegral `fmap` (p `peekElemOff` 4)
b5 <- fromIntegral `fmap` (p `peekElemOff` 5)
b6 <- fromIntegral `fmap` (p `peekElemOff` 6)
b7 <- fromIntegral `fmap` (p `peekElemOff` 7)
return $! (b0 `shiftl_w64` 56) .|.
(b1 `shiftl_w64` 48) .|.
(b2 `shiftl_w64` 40) .|.
(b3 `shiftl_w64` 32) .|.
(b4 `shiftl_w64` 24) .|.
(b5 `shiftl_w64` 16) .|.
(b6 `shiftl_w64` 8) .|.
(b7 )
{-# INLINE getWord64be #-}
-- | Read a Word64 in little endian format
getWord64le :: Ptr Word8 -> IO Word64
getWord64le = if byteOrder == LittleEndian
then \p -> peek (castPtr p)
else \p -> do
b0 <- fromIntegral `fmap` (p `peekElemOff` 0)
b1 <- fromIntegral `fmap` (p `peekElemOff` 1)
b2 <- fromIntegral `fmap` (p `peekElemOff` 2)
b3 <- fromIntegral `fmap` (p `peekElemOff` 3)
b4 <- fromIntegral `fmap` (p `peekElemOff` 4)
b5 <- fromIntegral `fmap` (p `peekElemOff` 5)
b6 <- fromIntegral `fmap` (p `peekElemOff` 6)
b7 <- fromIntegral `fmap` (p `peekElemOff` 7)
return $! (b7 `shiftl_w64` 56) .|.
(b6 `shiftl_w64` 48) .|.
(b5 `shiftl_w64` 40) .|.
(b4 `shiftl_w64` 32) .|.
(b3 `shiftl_w64` 24) .|.
(b2 `shiftl_w64` 16) .|.
(b1 `shiftl_w64` 8) .|.
(b0 )
{-# INLINE getWord64le #-}
------------------------------------------------------------------------
-- Unchecked shifts
{-# INLINE shiftr_w16 #-}
shiftr_w16 :: Word16 -> Int -> Word16
{-# INLINE shiftr_w32 #-}
shiftr_w32 :: Word32 -> Int -> Word32
{-# INLINE shiftr_w64 #-}
shiftr_w64 :: Word64 -> Int -> Word64
#if defined(__GLASGOW_HASKELL__) && !defined(__HADDOCK__)
shiftr_w16 (W16# w) (I# i) = W16# (w `uncheckedShiftRL#` i)
shiftr_w32 (W32# w) (I# i) = W32# (w `uncheckedShiftRL#` i)
#if WORD_SIZE_IN_BITS < 64
shiftr_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftRL64#` i)
#if __GLASGOW_HASKELL__ <= 606
-- Exported by GHC.Word in GHC 6.8 and higher
foreign import ccall unsafe "stg_uncheckedShiftRL64"
uncheckedShiftRL64# :: Word64# -> Int# -> Word64#
#endif
#else
shiftr_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftRL#` i)
#endif
#else
shiftr_w16 = shiftR
shiftr_w32 = shiftR
shiftr_w64 = shiftR
#endif
------------------------------------------------------------------------
-- Unchecked shifts
shiftl_w16 :: Word16 -> Int -> Word16
shiftl_w32 :: Word32 -> Int -> Word32
shiftl_w64 :: Word64 -> Int -> Word64
#if defined(__GLASGOW_HASKELL__) && !defined(__HADDOCK__)
shiftl_w16 (W16# w) (I# i) = W16# (w `uncheckedShiftL#` i)
shiftl_w32 (W32# w) (I# i) = W32# (w `uncheckedShiftL#` i)
#if WORD_SIZE_IN_BITS < 64
shiftl_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftL64#` i)
#if __GLASGOW_HASKELL__ <= 606
-- Exported by GHC.Word in GHC 6.8 and higher
foreign import ccall unsafe "stg_uncheckedShiftL64"
uncheckedShiftL64# :: Word64# -> Int# -> Word64#
#endif
#else
shiftl_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftL#` i)
#endif
#else
shiftl_w16 = shiftL
shiftl_w32 = shiftL
shiftl_w64 = shiftL
#endif