{-# LANGUAGE CPP #-} {-# LANGUAGE DerivingStrategies #-} {-# LANGUAGE GeneralizedNewtypeDeriving #-} {-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE Trustworthy #-} {-# OPTIONS_GHC -Wno-unused-binds #-} -- XXX -Wno-unused-binds stops us warning about unused constructors, -- but really we should just remove them if we don't want them ----------------------------------------------------------------------------- -- | -- 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. -- ----------------------------------------------------------------------------- #include module Foreign.C.Types ( -- * Representations of C types -- $ctypes -- ** #platform# Platform differences -- | This module contains platform specific information about types. -- __/As such, the types presented on this page reflect the/__ -- __/platform on which the documentation was generated and may/__ -- __/not coincide with the types on your platform./__ -- ** Integral types -- | These types 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', 'Data.Typeable.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(..), CBool(..) , CIntPtr(..), CUIntPtr(..), CIntMax(..), CUIntMax(..) -- ** Numeric types -- | These types 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', 'Data.Typeable.Typeable' and -- 'Storable'. , CClock(..), CTime(..), CUSeconds(..), CSUSeconds(..) -- extracted from CTime, because we don't want this comment in -- the Haskell language reports: -- | To convert 'CTime' to 'Data.Time.UTCTime', use the following: -- -- > \t -> posixSecondsToUTCTime (realToFrac t :: POSIXTime) -- -- ** Floating types -- | These types 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', 'Data.Typeable.Typeable', 'Storable', -- 'Prelude.Real', 'Prelude.Fractional', 'Prelude.Floating', -- 'Prelude.RealFrac' and 'Prelude.RealFloat'. That does mean -- that `CFloat`'s (respectively `CDouble`'s) instances of -- 'Prelude.Eq', 'Prelude.Ord', 'Prelude.Num' and -- 'Prelude.Fractional' are as badly behaved as `Prelude.Float`'s -- (respectively `Prelude.Double`'s). , CFloat(..), CDouble(..) -- XXX GHC doesn't support CLDouble yet -- , CLDouble(..) -- See Note [Exporting constructors of marshallable foreign types] -- in Foreign.Ptr for why the constructors for these newtypes are -- exported. -- ** Other types -- Instances of: Eq and Storable , CFile, CFpos, CJmpBuf ) where import Foreign.Storable import Data.Bits ( Bits(..), FiniteBits(..) ) import Data.Int ( Int8, Int16, Int32, Int64 ) import Data.Word ( Word8, Word16, Word32, Word64 ) import GHC.Base import GHC.Float import GHC.Enum import GHC.Real import GHC.Show import GHC.Read import GHC.Num import GHC.Ix #include "HsBaseConfig.h" #include "CTypes.h" -- | Haskell type representing the C @char@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CChar,"char",HTYPE_CHAR) -- | Haskell type representing the C @signed char@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CSChar,"signed char",HTYPE_SIGNED_CHAR) -- | Haskell type representing the C @unsigned char@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CUChar,"unsigned char",HTYPE_UNSIGNED_CHAR) -- | Haskell type representing the C @short@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CShort,"short",HTYPE_SHORT) -- | Haskell type representing the C @unsigned short@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CUShort,"unsigned short",HTYPE_UNSIGNED_SHORT) -- | Haskell type representing the C @int@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CInt,"int",HTYPE_INT) -- | Haskell type representing the C @unsigned int@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CUInt,"unsigned int",HTYPE_UNSIGNED_INT) -- | Haskell type representing the C @long@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CLong,"long",HTYPE_LONG) -- | Haskell type representing the C @unsigned long@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CULong,"unsigned long",HTYPE_UNSIGNED_LONG) -- | Haskell type representing the C @long long@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CLLong,"long long",HTYPE_LONG_LONG) -- | Haskell type representing the C @unsigned long long@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CULLong,"unsigned long long",HTYPE_UNSIGNED_LONG_LONG) -- | Haskell type representing the C @bool@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ -- -- @since 4.10.0.0 INTEGRAL_TYPE(CBool,"bool",HTYPE_BOOL) -- | Haskell type representing the C @float@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ FLOATING_TYPE(CFloat,"float",HTYPE_FLOAT) -- | Haskell type representing the C @double@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ FLOATING_TYPE(CDouble,"double",HTYPE_DOUBLE) -- XXX GHC doesn't support CLDouble yet {-# RULES "realToFrac/a->CFloat" realToFrac = \x -> CFloat (realToFrac x) "realToFrac/a->CDouble" realToFrac = \x -> CDouble (realToFrac x) "realToFrac/CFloat->a" realToFrac = \(CFloat x) -> realToFrac x "realToFrac/CDouble->a" realToFrac = \(CDouble x) -> realToFrac x #-} -- GHC doesn't support CLDouble yet -- "realToFrac/a->CLDouble" realToFrac = \x -> CLDouble (realToFrac x) -- "realToFrac/CLDouble->a" realToFrac = \(CLDouble x) -> realToFrac x -- | Haskell type representing the C @ptrdiff_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CPtrdiff,"ptrdiff_t",HTYPE_PTRDIFF_T) -- | Haskell type representing the C @size_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CSize,"size_t",HTYPE_SIZE_T) -- | Haskell type representing the C @wchar_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ INTEGRAL_TYPE(CWchar,"wchar_t",HTYPE_WCHAR_T) #if defined(HTYPE_SIG_ATOMIC_T) -- | Haskell type representing the C @sig_atomic_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ -- See Note [Lack of signals on wasm32-wasi]. INTEGRAL_TYPE(CSigAtomic,"sig_atomic_t",HTYPE_SIG_ATOMIC_T) #else newtype CSigAtomic = CSigAtomic Int32 deriving newtype (Read, Show, ARITHMETIC_CLASSES, INTEGRAL_CLASSES, Ix) #endif -- | Haskell type representing the C @clock_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ ARITHMETIC_TYPE(CClock,"clock_t",HTYPE_CLOCK_T) -- | Haskell type representing the C @time_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ ARITHMETIC_TYPE(CTime,"time_t",HTYPE_TIME_T) -- | Haskell type representing the C @useconds_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ -- -- @since 4.4.0.0 ARITHMETIC_TYPE(CUSeconds,"useconds_t",HTYPE_USECONDS_T) -- | Haskell type representing the C @suseconds_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ -- -- @since 4.4.0.0 ARITHMETIC_TYPE(CSUSeconds,"suseconds_t",HTYPE_SUSECONDS_T) -- FIXME: Implement and provide instances for Eq and Storable -- | Haskell type representing the C @FILE@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ data CFile = CFile -- | Haskell type representing the C @fpos_t@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ data CFpos = CFpos -- | Haskell type representing the C @jmp_buf@ type. -- /(The concrete types of "Foreign.C.Types#platform" are platform-specific.)/ data CJmpBuf = CJmpBuf INTEGRAL_TYPE(CIntPtr,"intptr_t",HTYPE_INTPTR_T) INTEGRAL_TYPE(CUIntPtr,"uintptr_t",HTYPE_UINTPTR_T) INTEGRAL_TYPE(CIntMax,"intmax_t",HTYPE_INTMAX_T) INTEGRAL_TYPE(CUIntMax,"uintmax_t",HTYPE_UINTMAX_T) -- 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@. -}