    {-# OPTIONS_GHC -fno-implicit-prelude #-}
    -----------------------------------------------------------------------------
    -- |
    -- Module      :  Foreign.C.Types
    -- Copyright   :  (c) The FFI task force 2001
    -- License     :  BSD-style (see the file libraries/base/LICENSE)
    --
    -- Maintainer  :  ffi@haskell.org
    -- Stability   :  provisional
    -- Portability :  portable
    --
    -- Mapping of C types to corresponding Haskell types.
    --
    -----------------------------------------------------------------------------

    module Foreign.C.Types
    	( -- * Representations of C types
    #ifndef __NHC__
    	  -- $ctypes

    	  -- ** Integral types
    	  -- | These types are are represented as @newtype@s of
    	  -- types in "Data.Int" and "Data.Word", and are instances of
    	  -- 'Prelude.Eq', 'Prelude.Ord', 'Prelude.Num', 'Prelude.Read',
    	  -- 'Prelude.Show', 'Prelude.Enum', 'Typeable', 'Storable',
    	  -- 'Prelude.Bounded', 'Prelude.Real', 'Prelude.Integral' and
    	  -- 'Bits'.
    	  CChar,  CSChar,  CUChar
    	, CShort, CUShort, CInt,   CUInt
    	, CLong,  CULong
    	, CPtrdiff, CSize, CWchar, CSigAtomic
            , CLLong, CULLong
    	, CIntPtr, CUIntPtr
    	, CIntMax, CUIntMax

    	  -- ** Numeric types
    	  -- | These types are are represented as @newtype@s of basic
    	  -- foreign types, and are instances of
    	  -- 'Prelude.Eq', 'Prelude.Ord', 'Prelude.Num', 'Prelude.Read',
    	  -- 'Prelude.Show', 'Prelude.Enum', 'Typeable' and 'Storable'.
    	, CClock,   CTime

    	  -- ** Floating types
    	  -- | These types are are represented as @newtype@s of
    	  -- 'Prelude.Float' and 'Prelude.Double', and are instances of
    	  -- 'Prelude.Eq', 'Prelude.Ord', 'Prelude.Num', 'Prelude.Read',
    	  -- 'Prelude.Show', 'Prelude.Enum', 'Typeable', 'Storable',
    	  -- 'Prelude.Real', 'Prelude.Fractional', 'Prelude.Floating',
    	  -- 'Prelude.RealFrac' and 'Prelude.RealFloat'.
    	, CFloat,  CDouble, CLDouble
    #else
    	  -- Exported non-abstractly in nhc98 to fix an interface file problem.
    	  CChar(..),    CSChar(..),  CUChar(..)
    	, CShort(..),   CUShort(..), CInt(..),   CUInt(..)
    	, CLong(..),    CULong(..)
    	, CPtrdiff(..), CSize(..),   CWchar(..), CSigAtomic(..)
            , CLLong(..),   CULLong(..)
    	, CClock(..),   CTime(..)
    	, CFloat(..),   CDouble(..), CLDouble(..)
    #endif
    	  -- ** Other types

              -- Instances of: Eq and Storable
    	, CFile,        CFpos,     CJmpBuf
    	) where

    #ifndef __NHC__

    import {-# SOURCE #-} Foreign.Storable
    import Data.Bits	( Bits(..) )
    import Data.Int		( Int8,  Int16,  Int32,  Int64  )
    import Data.Word	( Word8, Word16, Word32, Word64 )
    import {-# SOURCE #-} Data.Typeable

    #ifdef __GLASGOW_HASKELL__
    import GHC.Base
    import GHC.Float
    import GHC.Enum
    import GHC.Real
    import GHC.Show
    import GHC.Read
    import GHC.Num
    #else
    import Control.Monad	( liftM )
    #endif

    #ifdef __HUGS__
    import Hugs.Ptr		( castPtr )
    #endif

    #include "HsBaseConfig.h"
    #include "CTypes.h"

    -- | Haskell type representing the C @char@ type.
    INTEGRAL_TYPE(CChar,tyConCChar,"CChar",HTYPE_CHAR)
    -- | Haskell type representing the C @signed char@ type.
    INTEGRAL_TYPE(CSChar,tyConCSChar,"CSChar",HTYPE_SIGNED_CHAR)
    -- | Haskell type representing the C @unsigned char@ type.
    INTEGRAL_TYPE(CUChar,tyConCUChar,"CUChar",HTYPE_UNSIGNED_CHAR)

    -- | Haskell type representing the C @short@ type.
    INTEGRAL_TYPE(CShort,tyConCShort,"CShort",HTYPE_SHORT)
    -- | Haskell type representing the C @unsigned short@ type.
    INTEGRAL_TYPE(CUShort,tyConCUShort,"CUShort",HTYPE_UNSIGNED_SHORT)

    -- | Haskell type representing the C @int@ type.
    INTEGRAL_TYPE(CInt,tyConCInt,"CInt",HTYPE_INT)
    -- | Haskell type representing the C @unsigned int@ type.
    INTEGRAL_TYPE(CUInt,tyConCUInt,"CUInt",HTYPE_UNSIGNED_INT)

    -- | Haskell type representing the C @long@ type.
    INTEGRAL_TYPE(CLong,tyConCLong,"CLong",HTYPE_LONG)
    -- | Haskell type representing the C @unsigned long@ type.
    INTEGRAL_TYPE(CULong,tyConCULong,"CULong",HTYPE_UNSIGNED_LONG)

    -- | Haskell type representing the C @long long@ type.
    INTEGRAL_TYPE(CLLong,tyConCLLong,"CLLong",HTYPE_LONG_LONG)
    -- | Haskell type representing the C @unsigned long long@ type.
    INTEGRAL_TYPE(CULLong,tyConCULLong,"CULLong",HTYPE_UNSIGNED_LONG_LONG)

    {-# RULES
    "fromIntegral/a->CChar"   fromIntegral = \x -> CChar   (fromIntegral x)
    "fromIntegral/a->CSChar"  fromIntegral = \x -> CSChar  (fromIntegral x)
    "fromIntegral/a->CUChar"  fromIntegral = \x -> CUChar  (fromIntegral x)
    "fromIntegral/a->CShort"  fromIntegral = \x -> CShort  (fromIntegral x)
    "fromIntegral/a->CUShort" fromIntegral = \x -> CUShort (fromIntegral x)
    "fromIntegral/a->CInt"    fromIntegral = \x -> CInt    (fromIntegral x)
    "fromIntegral/a->CUInt"   fromIntegral = \x -> CUInt   (fromIntegral x)
    "fromIntegral/a->CLong"   fromIntegral = \x -> CLong   (fromIntegral x)
    "fromIntegral/a->CULong"  fromIntegral = \x -> CULong  (fromIntegral x)
    "fromIntegral/a->CLLong"  fromIntegral = \x -> CLLong  (fromIntegral x)
    "fromIntegral/a->CULLong" fromIntegral = \x -> CULLong (fromIntegral x)

    "fromIntegral/CChar->a"   fromIntegral = \(CChar   x) -> fromIntegral x
    "fromIntegral/CSChar->a"  fromIntegral = \(CSChar  x) -> fromIntegral x
    "fromIntegral/CUChar->a"  fromIntegral = \(CUChar  x) -> fromIntegral x
    "fromIntegral/CShort->a"  fromIntegral = \(CShort  x) -> fromIntegral x
    "fromIntegral/CUShort->a" fromIntegral = \(CUShort x) -> fromIntegral x
    "fromIntegral/CInt->a"    fromIntegral = \(CInt    x) -> fromIntegral x
    "fromIntegral/CUInt->a"   fromIntegral = \(CUInt   x) -> fromIntegral x
    "fromIntegral/CLong->a"   fromIntegral = \(CLong   x) -> fromIntegral x
    "fromIntegral/CULong->a"  fromIntegral = \(CULong  x) -> fromIntegral x
    "fromIntegral/CLLong->a"  fromIntegral = \(CLLong  x) -> fromIntegral x
    "fromIntegral/CULLong->a" fromIntegral = \(CULLong x) -> fromIntegral x
     #-}

    -- | Haskell type representing the C @float@ type.
    FLOATING_TYPE(CFloat,tyConCFloat,"CFloat",HTYPE_FLOAT)
    -- | Haskell type representing the C @double@ type.
    FLOATING_TYPE(CDouble,tyConCDouble,"CDouble",HTYPE_DOUBLE)
    -- HACK: Currently no long double in the FFI, so we simply re-use double
    -- | Haskell type representing the C @long double@ type.
    FLOATING_TYPE(CLDouble,tyConCLDouble,"CLDouble",HTYPE_DOUBLE)

    {-# RULES
    "realToFrac/a->CFloat"    realToFrac = \x -> CFloat   (realToFrac x)
    "realToFrac/a->CDouble"   realToFrac = \x -> CDouble  (realToFrac x)
    "realToFrac/a->CLDouble"  realToFrac = \x -> CLDouble (realToFrac x)

    "realToFrac/CFloat->a"    realToFrac = \(CFloat   x) -> realToFrac x
    "realToFrac/CDouble->a"   realToFrac = \(CDouble  x) -> realToFrac x
    "realToFrac/CLDouble->a"  realToFrac = \(CLDouble x) -> realToFrac x
     #-}

    -- | Haskell type representing the C @ptrdiff_t@ type.
    INTEGRAL_TYPE(CPtrdiff,tyConCPtrdiff,"CPtrdiff",HTYPE_PTRDIFF_T)
    -- | Haskell type representing the C @size_t@ type.
    INTEGRAL_TYPE(CSize,tyConCSize,"CSize",HTYPE_SIZE_T)
    -- | Haskell type representing the C @wchar_t@ type.
    INTEGRAL_TYPE(CWchar,tyConCWchar,"CWchar",HTYPE_WCHAR_T)
    -- | Haskell type representing the C @sig_atomic_t@ type.
    INTEGRAL_TYPE(CSigAtomic,tyConCSigAtomic,"CSigAtomic",HTYPE_SIG_ATOMIC_T)

    {-# RULES
    "fromIntegral/a->CPtrdiff"   fromIntegral = \x -> CPtrdiff   (fromIntegral x)
    "fromIntegral/a->CSize"      fromIntegral = \x -> CSize      (fromIntegral x)
    "fromIntegral/a->CWchar"     fromIntegral = \x -> CWchar     (fromIntegral x)
    "fromIntegral/a->CSigAtomic" fromIntegral = \x -> CSigAtomic (fromIntegral x)

    "fromIntegral/CPtrdiff->a"   fromIntegral = \(CPtrdiff   x) -> fromIntegral x
    "fromIntegral/CSize->a"      fromIntegral = \(CSize      x) -> fromIntegral x
    "fromIntegral/CWchar->a"     fromIntegral = \(CWchar     x) -> fromIntegral x
    "fromIntegral/CSigAtomic->a" fromIntegral = \(CSigAtomic x) -> fromIntegral x
     #-}

    -- | Haskell type representing the C @clock_t@ type.
    ARITHMETIC_TYPE(CClock,tyConCClock,"CClock",HTYPE_CLOCK_T)
    -- | Haskell type representing the C @time_t@ type.
    --
    -- To convert to a @Data.Time.UTCTime@, use the following formula:
    --
    -- >  posixSecondsToUTCTime (realToFrac :: POSIXTime)
    --
    ARITHMETIC_TYPE(CTime,tyConCTime,"CTime",HTYPE_TIME_T)

    -- FIXME: Implement and provide instances for Eq and Storable
    -- | Haskell type representing the C @FILE@ type.
    data CFile = CFile
    -- | Haskell type representing the C @fpos_t@ type.
    data CFpos = CFpos
    -- | Haskell type representing the C @jmp_buf@ type.
    data CJmpBuf = CJmpBuf

    INTEGRAL_TYPE(CIntPtr,tyConCIntPtr,"CIntPtr",HTYPE_INTPTR_T)
    INTEGRAL_TYPE(CUIntPtr,tyConCUIntPtr,"CUIntPtr",HTYPE_UINTPTR_T)
    INTEGRAL_TYPE(CIntMax,tyConCIntMax,"CIntMax",HTYPE_INTMAX_T)
    INTEGRAL_TYPE(CUIntMax,tyConCUIntMax,"CUIntMax",HTYPE_UINTMAX_T)

    {-# RULES
    "fromIntegral/a->CIntPtr"  fromIntegral = \x -> CIntPtr  (fromIntegral x)
    "fromIntegral/a->CUIntPtr" fromIntegral = \x -> CUIntPtr (fromIntegral x)
    "fromIntegral/a->CIntMax"  fromIntegral = \x -> CIntMax  (fromIntegral x)
    "fromIntegral/a->CUIntMax" fromIntegral = \x -> CUIntMax (fromIntegral x)
     #-}

    -- C99 types which are still missing include:
    -- wint_t, wctrans_t, wctype_t

    {- $ctypes

    These types are needed to accurately represent C function prototypes,
    in order to access C library interfaces in Haskell.  The Haskell system
    is not required to represent those types exactly as C does, but the
    following guarantees are provided concerning a Haskell type @CT@
    representing a C type @t@:

    * If a C function prototype has @t@ as an argument or result type, the
      use of @CT@ in the corresponding position in a foreign declaration
      permits the Haskell program to access the full range of values encoded
      by the C type; and conversely, any Haskell value for @CT@ has a valid
      representation in C.

    * @'sizeOf' ('Prelude.undefined' :: CT)@ will yield the same value as
      @sizeof (t)@ in C.

    * @'alignment' ('Prelude.undefined' :: CT)@ matches the alignment
      constraint enforced by the C implementation for @t@.

    * The members 'peek' and 'poke' of the 'Storable' class map all values
      of @CT@ to the corresponding value of @t@ and vice versa.

    * When an instance of 'Prelude.Bounded' is defined for @CT@, the values
      of 'Prelude.minBound' and 'Prelude.maxBound' coincide with @t_MIN@
      and @t_MAX@ in C.

    * When an instance of 'Prelude.Eq' or 'Prelude.Ord' is defined for @CT@,
      the predicates defined by the type class implement the same relation
      as the corresponding predicate in C on @t@.

    * When an instance of 'Prelude.Num', 'Prelude.Read', 'Prelude.Integral',
      'Prelude.Fractional', 'Prelude.Floating', 'Prelude.RealFrac', or
      'Prelude.RealFloat' is defined for @CT@, the arithmetic operations
      defined by the type class implement the same function as the
      corresponding arithmetic operations (if available) in C on @t@.

    * When an instance of 'Bits' is defined for @CT@, the bitwise operation
      defined by the type class implement the same function as the
      corresponding bitwise operation in C on @t@.

    -}

    #else	/* __NHC__ */

    import NHC.FFI
      ( CChar(..),    CSChar(..),  CUChar(..)
      , CShort(..),   CUShort(..), CInt(..),   CUInt(..)
      , CLong(..),    CULong(..),  CLLong(..), CULLong(..)
      , CPtrdiff(..), CSize(..),   CWchar(..), CSigAtomic(..)
      , CClock(..),   CTime(..)
      , CFloat(..),   CDouble(..), CLDouble(..)
      , CFile,        CFpos,       CJmpBuf
      , Storable(..)
      )
    import Data.Bits
    import NHC.SizedTypes

    #define INSTANCE_BITS(T) \
    instance Bits T where { \
      (T x) .&.     (T y)   = T (x .&.   y) ; \
      (T x) .|.     (T y)   = T (x .|.   y) ; \
      (T x) `xor`   (T y)   = T (x `xor` y) ; \
      complement    (T x)   = T (complement x) ; \
      shift         (T x) n = T (shift x n) ; \
      rotate        (T x) n = T (rotate x n) ; \
      bit                 n = T (bit n) ; \
      setBit        (T x) n = T (setBit x n) ; \
      clearBit      (T x) n = T (clearBit x n) ; \
      complementBit (T x) n = T (complementBit x n) ; \
      testBit       (T x) n = testBit x n ; \
      bitSize       (T x)   = bitSize x ; \
      isSigned      (T x)   = isSigned x }

    INSTANCE_BITS(CChar)
    INSTANCE_BITS(CSChar)
    INSTANCE_BITS(CUChar)
    INSTANCE_BITS(CShort)
    INSTANCE_BITS(CUShort)
    INSTANCE_BITS(CInt)
    INSTANCE_BITS(CUInt)
    INSTANCE_BITS(CLong)
    INSTANCE_BITS(CULong)
    INSTANCE_BITS(CLLong)
    INSTANCE_BITS(CULLong)
    INSTANCE_BITS(CPtrdiff)
    INSTANCE_BITS(CWchar)
    INSTANCE_BITS(CSigAtomic)
    INSTANCE_BITS(CSize)

    #endif