import CoreUtils ( exprType, mkInlineMe )
import Id ( Id, idType, idName, mkSysLocal, setInlinePragma )
import Literal ( Literal(..), mkStringLit )
-import Module ( moduleFS )
+import Module ( moduleNameFS, moduleName )
import Name ( getOccString, NamedThing(..) )
import Type ( repType, coreEqType )
+import Coercion ( mkUnsafeCoercion )
import TcType ( Type, mkFunTys, mkForAllTys, mkTyConApp,
- mkFunTy, tcSplitTyConApp_maybe,
+ mkFunTy, tcSplitTyConApp_maybe, tcSplitIOType_maybe,
tcSplitForAllTys, tcSplitFunTys, tcTyConAppArgs,
+ isBoolTy
)
import BasicTypes ( Boxity(..) )
import HscTypes ( ForeignStubs(..) )
import ForeignCall ( ForeignCall(..), CCallSpec(..),
- Safety(..), playSafe,
+ Safety(..),
CExportSpec(..), CLabelString,
CCallConv(..), ccallConvToInt,
ccallConvAttribute
)
import TysWiredIn ( unitTy, tupleTyCon )
-import TysPrim ( addrPrimTy, mkStablePtrPrimTy, alphaTy )
-import PrelNames ( hasKey, ioTyConKey, stablePtrTyConName, newStablePtrName, bindIOName,
+import TysPrim ( addrPrimTy, mkStablePtrPrimTy, alphaTy, intPrimTy )
+import PrelNames ( stablePtrTyConName, newStablePtrName, bindIOName,
checkDotnetResName )
import BasicTypes ( Activation( NeverActive ) )
import SrcLoc ( Located(..), unLoc )
combine stubs (L loc decl) = putSrcSpanDs loc (combine1 stubs decl)
combine1 (ForeignStubs acc_h acc_c acc_hdrs acc_feb, acc_f)
- (ForeignImport id _ spec depr)
+ (ForeignImport id _ spec)
= traceIf (text "fi start" <+> ppr id) `thenDs` \ _ ->
dsFImport (unLoc id) spec `thenDs` \ (bs, h, c, mbhd) ->
- warnDepr depr `thenDs` \ _ ->
traceIf (text "fi end" <+> ppr id) `thenDs` \ _ ->
returnDs (ForeignStubs (h $$ acc_h)
(c $$ acc_c)
bs ++ acc_f)
combine1 (ForeignStubs acc_h acc_c acc_hdrs acc_feb, acc_f)
- (ForeignExport (L _ id) _ (CExport (CExportStatic ext_nm cconv)) depr)
+ (ForeignExport (L _ id) _ (CExport (CExportStatic ext_nm cconv)))
= dsFExport id (idType id)
ext_nm cconv False `thenDs` \(h, c, _, _) ->
- warnDepr depr `thenDs` \_ ->
returnDs (ForeignStubs (h $$ acc_h) (c $$ acc_c) acc_hdrs (id:acc_feb),
acc_f)
addH (Just e) ls
| e `elem` ls = ls
| otherwise = e:ls
-
- warnDepr False = returnDs ()
- warnDepr True = dsWarn msg
- where
- msg = ptext SLIT("foreign declaration uses deprecated non-standard syntax")
\end{code}
wrap_rhs = mkInlineMe (mkLams (tvs ++ args) wrapper_body)
in
returnDs ([(work_id, work_rhs), (fn_id, wrap_rhs)], empty, empty)
-
-unsafe_call (CCall (CCallSpec _ _ safety)) = playSafe safety
-unsafe_call (DNCall _) = False
\end{code}
-- Look at the result type of the exported function, orig_res_ty
-- If it's IO t, return (t, True)
-- If it's plain t, return (t, False)
- (case tcSplitTyConApp_maybe orig_res_ty of
- -- We must use tcSplit here so that we see the (IO t) in
- -- the type. [IO t is transparent to plain splitTyConApp.]
-
- Just (ioTyCon, [res_ty])
- -> ASSERT( ioTyCon `hasKey` ioTyConKey )
- -- The function already returns IO t
- returnDs (res_ty, True)
-
- other -> -- The function returns t
- returnDs (orig_res_ty, False)
- )
- `thenDs` \ (res_ty, -- t
+ (case tcSplitIOType_maybe orig_res_ty of
+ Just (ioTyCon, res_ty) -> returnDs (res_ty, True)
+ -- The function already returns IO t
+ Nothing -> returnDs (orig_res_ty, False)
+ -- The function returns t
+ ) `thenDs` \ (res_ty, -- t
is_IO_res_ty) -> -- Bool
returnDs $
mkFExportCBits ext_name
fe_arg_tys res_ty is_IO_res_ty cconv
\end{code}
-@foreign export dynamic@ lets you dress up Haskell IO actions
-of some fixed type behind an externally callable interface (i.e.,
-as a C function pointer). Useful for callbacks and stuff.
+@foreign import "wrapper"@ (previously "foreign export dynamic") lets
+you dress up Haskell IO actions of some fixed type behind an
+externally callable interface (i.e., as a C function pointer). Useful
+for callbacks and stuff.
\begin{verbatim}
-foreign export dynamic f :: (Addr -> Int -> IO Int) -> IO Addr
+type Fun = Bool -> Int -> IO Int
+foreign import "wrapper" f :: Fun -> IO (FunPtr Fun)
-- Haskell-visible constructor, which is generated from the above:
-- SUP: No check for NULL from createAdjustor anymore???
-f :: (Addr -> Int -> IO Int) -> IO Addr
+f :: Fun -> IO (FunPtr Fun)
f cback =
bindIO (newStablePtr cback)
(\StablePtr sp# -> IO (\s1# ->
- case _ccall_ createAdjustor cconv sp# ``f_helper'' s1# of
+ case _ccall_ createAdjustor cconv sp# ``f_helper'' <arg info> s1# of
(# s2#, a# #) -> (# s2#, A# a# #)))
-foreign export "f_helper" f_helper :: StablePtr (Addr -> Int -> IO Int) -> Addr -> Int -> IO Int
--- `special' foreign export that invokes the closure pointed to by the
--- first argument.
+foreign import "&f_helper" f_helper :: FunPtr (StablePtr Fun -> Fun)
+
+-- and the helper in C:
+
+f_helper(StablePtr s, HsBool b, HsInt i)
+{
+ rts_evalIO(rts_apply(rts_apply(deRefStablePtr(s),
+ rts_mkBool(b)), rts_mkInt(i)));
+}
\end{verbatim}
\begin{code}
-> DsM ([Binding], SDoc, SDoc)
dsFExportDynamic id cconv
= newSysLocalDs ty `thenDs` \ fe_id ->
- getModuleDs `thenDs` \ mod_name ->
+ getModuleDs `thenDs` \ mod ->
let
-- hack: need to get at the name of the C stub we're about to generate.
- fe_nm = mkFastString (unpackFS (zEncodeFS (moduleFS mod_name)) ++ "_" ++ toCName fe_id)
+ fe_nm = mkFastString (unpackFS (zEncodeFS (moduleNameFS (moduleName mod))) ++ "_" ++ toCName fe_id)
in
newSysLocalDs arg_ty `thenDs` \ cback ->
dsLookupGlobalId newStablePtrName `thenDs` \ newStablePtrId ->
-- PlayRisky: the adjustor doesn't allocate in the Haskell heap or do a callback
let ccall_adj_ty = exprType ccall_adj
ccall_io_adj = mkLams [stbl_value] $
- Note (Coerce io_res_ty ccall_adj_ty)
- ccall_adj
+ (pprTrace "DsForeign: why is there an unsafeCoerce here?" (text "") $
+ (Cast ccall_adj (mkUnsafeCoercion ccall_adj_ty io_res_ty )))
+
io_app = mkLams tvs $
mkLams [cback] $
stbl_app ccall_io_adj res_ty
typeMachRep addrPrimTy)
-- This function returns the primitive type associated with the boxed
--- type argument to a foreign export (eg. Int ==> Int#). It assumes
--- that all the types we are interested in have a single constructor
--- with a single primitive-typed argument, which is true for all of the legal
--- foreign export argument types (see TcType.legalFEArgTyCon).
+-- type argument to a foreign export (eg. Int ==> Int#).
getPrimTyOf :: Type -> Type
-getPrimTyOf ty =
- case splitProductType_maybe (repType ty) of
+getPrimTyOf ty
+ | isBoolTy rep_ty = intPrimTy
+ -- Except for Bool, the types we are interested in have a single constructor
+ -- with a single primitive-typed argument (see TcType.legalFEArgTyCon).
+ | otherwise =
+ case splitProductType_maybe rep_ty of
Just (_, _, data_con, [prim_ty]) ->
ASSERT(dataConSourceArity data_con == 1)
ASSERT2(isUnLiftedType prim_ty, ppr prim_ty)
prim_ty
_other -> pprPanic "DsForeign.getPrimTyOf" (ppr ty)
+ where
+ rep_ty = repType ty
\end{code}