-- C->Haskell Compiler: binding generator -- vim:ts=8:noexpandtab -- -- Copyright (c) [1999..2003] Manuel M T Chakravarty -- -- This file is free software; you can redistribute it and/or modify -- it under the terms of the GNU General Public License as published by -- the Free Software Foundation; either version 2 of the License, or -- (at your option) any later version. -- -- This file is distributed in the hope that it will be useful, -- but WITHOUT ANY WARRANTY; without even the implied warranty of -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -- GNU General Public License for more details. -- --- Description --------------------------------------------------------------- -- -- Language: Haskell 98 -- -- Module implementing the expansion of the binding hooks. -- -- * If there is an error in one binding hook, it is skipped and the next one -- is processed (to collect as many errors as possible). However, if at -- least one error occured, the expansion of binding hooks ends in a fatal -- exception. -- -- * `CST' exceptions are used to back off a binding hook as soon as an error -- is encountered while it is processed. -- -- Mapping of C types to Haskell FFI types: -- ---------------------------------------- -- -- The following defines the mapping for basic types. If the type specifer -- is missing, it is taken to be `int'. In the following, elements enclosed -- in square brackets are optional. -- -- void -> () -- char -> CChar -- unsigned char -> CUChar -- signed char -> CShort -- signed -> CInt -- [signed] int -> CInt -- [signed] short [int] -> CSInt -- [signed] long [int] -> CLong -- [signed] long long [int] -> CLLong -- unsigned [int] -> CUInt -- unsigned short [int] -> CUShort -- unsigned long [int] -> CULong -- unsigned long long [int] -> CULLong -- float -> CFloat -- double -> CDouble -- long double -> CLDouble -- enum ... -> CInt -- struct ... -> ** error ** -- union ... -> ** error ** -- -- Plain structures or unions (ie, if not the base type of a pointer type) -- are not supported at the moment (the underlying FFI does not support them -- directly). Named types (ie, in C type names defined using `typedef') are -- traced back to their original definitions. Pointer types are mapped -- to `Ptr a' or `FunPtr a' depending on whether they point to a functional. -- Values obtained from bit fields are represented by `CInt' or `CUInt' -- depending on whether they are signed. -- -- We obtain the size and alignment constraints for all primitive types of C -- from `CInfo', which obtains it from the Haskell 98 FFI. In the alignment -- computations involving bit fields, we assume that the alignment -- constraints for bitfields (wrt to non-bitfield members) is always the same -- as for `int' irrespective of the size of the bitfield. This seems to be -- implicitly guaranteed by K&R A8.3, but it is not entirely clear. -- -- Identifier lookup: -- ------------------ -- -- We allow to identify enumerations and structures by the names of `typedef' -- types aliased to them. -- -- * enumerations: It is first checked whether there is a tag with the given -- identifier; if such a tag does not exist, the definition of a typedef -- with the same name is taken if it exists. -- * structs/unions: like enumerations -- -- We generally use `shadow' lookups. When an identifier cannot be found, -- we check whether - according to the prefix set by the context hook - -- another identifier casts a shadow that matches. If so, that identifier is -- taken instead of the original one. -- --- ToDo ---------------------------------------------------------------------- -- -- * A function prototype that uses a defined type on its left hand side may -- declare a function, while that is not obvious from the declaration -- itself (without also considering the `typedef'). Calls to such -- functions are currently rejected, which is a BUG. -- -- * context hook must preceded all but the import hooks -- -- * The use of `++' in the recursive definition of the routines generating -- `Enum' instances is not particularly efficient. -- -- * Some operands are missing in `applyBin' - unfortunately, Haskell does -- not have standard bit operations. Some constructs are also missing -- from `evalConstCExpr'. Haskell 98 FFI standardises `Bits'; use that. -- module GenBind (expandHooks) where -- standard libraries import Data.Char (toLower) import Data.List (deleteBy, intersperse, find) import Data.Maybe (isNothing, fromJust, fromMaybe) import Control.Monad (when, unless, liftM, mapAndUnzipM) -- Compiler Toolkit import Position (Position, Pos(posOf), nopos, builtinPos) import Errors (interr, todo) import Idents (Ident, identToLexeme, onlyPosIdent) import Attributes (newAttrsOnlyPos) -- C->Haskell import C2HSConfig (PlatformSpec(..)) import C2HSState (CST, errorsPresent, showErrors, fatal, SwitchBoard(..), Traces(..), putTraceStr, getSwitch) import C (AttrC, CObj(..), CTag(..), CDecl(..), CDeclSpec(..), CTypeSpec(..), CStructUnion(..), CStructTag(..), CEnum(..), CDeclr(..), CExpr(..), CBinaryOp(..), CUnaryOp(..), CConst (..), runCT, ifCTExc, raiseErrorCTExc, findValueObj, findFunObj, findTag, applyPrefixToNameSpaces, simplifyDecl, declrNamed, structMembers, structName, tagName, declaredName , structFromDecl, funResultAndArgs, chaseDecl, findAndChaseDecl, checkForAlias, checkForOneAliasName, checkForOneCUName, lookupEnum, lookupStructUnion, lookupDeclOrTag, isPtrDeclr, dropPtrDeclr, isPtrDecl, getDeclOf, isFunDeclr, refersToNewDef, CDef(..)) -- friends import CHS (CHSModule(..), CHSFrag(..), CHSHook(..), CHSParm(..), CHSArg(..), CHSAccess(..), CHSAPath(..), CHSPtrType(..), showCHSParm, apathToIdent) import CInfo (CPrimType(..), size, alignment, getPlatform) import GBMonad (TransFun, transTabToTransFun, HsObject(..), GB, initialGBState, setContext, getPrefix, delayCode, getDelayedCode, ptrMapsTo, queryPtr, objIs, queryClass, queryPointer, mergeMaps, dumpMaps) -- default marshallers -- ------------------- -- FIXME: -- - we might have a dynamically extended table in the monad if needed (we -- could marshall enums this way and also save the `id' marshallers for -- pointers defined via (newtype) pointer hooks) -- - the checks for the Haskell types are quite kludgy -- determine the default "in" marshaller for the given Haskell and C types -- lookupDftMarshIn :: String -> [ExtType] -> GB (Maybe (Ident, CHSArg)) lookupDftMarshIn "Bool" [PrimET pt] | isIntegralCPrimType pt = return $ Just (cFromBoolIde, CHSValArg) lookupDftMarshIn hsTy [PrimET pt] | isIntegralHsType hsTy &&isIntegralCPrimType pt = return $ Just (cIntConvIde, CHSValArg) lookupDftMarshIn hsTy [PrimET pt] | isFloatHsType hsTy &&isFloatCPrimType pt = return $ Just (cFloatConvIde, CHSValArg) lookupDftMarshIn "String" [PtrET (PrimET CCharPT)] = return $ Just (withCStringIde, CHSIOArg) lookupDftMarshIn "String" [PtrET (PrimET CCharPT), PrimET pt] | isIntegralCPrimType pt = return $ Just (withCStringLenIde, CHSIOArg) lookupDftMarshIn hsTy [PtrET ty] | showExtType ty == hsTy = return $ Just (withIde, CHSIOArg) lookupDftMarshIn hsTy [PtrET (PrimET pt)] | isIntegralHsType hsTy && isIntegralCPrimType pt = return $ Just (withIntConvIde, CHSIOArg) lookupDftMarshIn hsTy [PtrET (PrimET pt)] | isFloatHsType hsTy && isFloatCPrimType pt = return $ Just (withFloatConvIde, CHSIOArg) lookupDftMarshIn "Bool" [PtrET (PrimET pt)] | isIntegralCPrimType pt = return $ Just (withFromBoolIde, CHSIOArg) -- FIXME: handle array-list conversion lookupDftMarshIn _ _ = return Nothing -- determine the default "out" marshaller for the given Haskell and C types -- lookupDftMarshOut :: String -> [ExtType] -> GB (Maybe (Ident, CHSArg)) lookupDftMarshOut "()" _ = return $ Just (voidIde, CHSVoidArg) lookupDftMarshOut "Bool" [PrimET pt] | isIntegralCPrimType pt = return $ Just (cToBoolIde, CHSValArg) lookupDftMarshOut hsTy [PrimET pt] | isIntegralHsType hsTy &&isIntegralCPrimType pt = return $ Just (cIntConvIde, CHSValArg) lookupDftMarshOut hsTy [PrimET pt] | isFloatHsType hsTy &&isFloatCPrimType pt = return $ Just (cFloatConvIde, CHSValArg) lookupDftMarshOut "String" [PtrET (PrimET CCharPT)] = return $ Just (peekCStringIde, CHSIOArg) lookupDftMarshOut "String" [PtrET (PrimET CCharPT), PrimET pt] | isIntegralCPrimType pt = return $ Just (peekCStringLenIde, CHSIOArg) lookupDftMarshOut hsTy [PtrET ty] | showExtType ty == hsTy = return $ Just (peekIde, CHSIOArg) -- FIXME: add combination, such as "peek" plus "cIntConv" etc -- FIXME: handle array-list conversion lookupDftMarshOut _ _ = return Nothing -- check for integral Haskell types -- isIntegralHsType :: String -> Bool isIntegralHsType "Int" = True isIntegralHsType "Int8" = True isIntegralHsType "Int16" = True isIntegralHsType "Int32" = True isIntegralHsType "Int64" = True isIntegralHsType "Word8" = True isIntegralHsType "Word16" = True isIntegralHsType "Word32" = True isIntegralHsType "Word64" = True isIntegralHsType _ = False -- check for floating Haskell types -- isFloatHsType :: String -> Bool isFloatHsType "Float" = True isFloatHsType "Double" = True isFloatHsType _ = False isVariadic :: ExtType -> Bool isVariadic (FunET s t) = any isVariadic [s,t] isVariadic (IOET t) = isVariadic t isVariadic (PtrET t) = isVariadic t isVariadic (VarFunET _) = True isVariadic _ = False -- check for integral C types -- -- * For marshalling purposes C char's are integral types (see also types -- classes for which the FFI guarantees instances for `CChar', `CSChar', and -- `CUChar') -- isIntegralCPrimType :: CPrimType -> Bool isIntegralCPrimType = (`elem` [CCharPT, CSCharPT, CIntPT, CShortPT, CLongPT, CLLongPT, CUIntPT, CUCharPT, CUShortPT, CULongPT, CULLongPT]) -- check for floating C types -- isFloatCPrimType :: CPrimType -> Bool isFloatCPrimType = (`elem` [CFloatPT, CDoublePT, CLDoublePT]) -- standard conversions -- voidIde = noPosIdent "void" -- never appears in the output cFromBoolIde = noPosIdent "cFromBool" cToBoolIde = noPosIdent "cToBool" cIntConvIde = noPosIdent "cIntConv" cFloatConvIde = noPosIdent "cFloatConv" withIde = noPosIdent "with" withCStringIde = noPosIdent "withCString" withCStringLenIde = noPosIdent "withCStringLenIntConv" withIntConvIde = noPosIdent "withIntConv" withFloatConvIde = noPosIdent "withFloatConv" withFromBoolIde = noPosIdent "withFromBoolConv" peekIde = noPosIdent "peek" peekCStringIde = noPosIdent "peekCString" peekCStringLenIde = noPosIdent "peekCStringLenIntConv" -- expansion of binding hooks -- -------------------------- -- given a C header file and a binding file, expand all hooks in the binding -- file using the C header information (EXPORTED) -- -- * together with the module, returns the contents of the .chi file -- -- * if any error (not warnings) is encountered, a fatal error is raised. -- -- * also returns all warning messages encountered (last component of result) -- expandHooks :: AttrC -> CHSModule -> CST s (CHSModule, String, String) expandHooks ac mod = do (_, res) <- runCT (expandModule mod) ac initialGBState return res expandModule :: CHSModule -> GB (CHSModule, String, String) expandModule (CHSModule frags) = do -- expand hooks -- traceInfoExpand frags' <- expandFrags frags delayedFrags <- getDelayedCode -- get .chi dump -- chi <- dumpMaps -- check for errors and finalise -- errs <- errorsPresent if errs then do traceInfoErr errmsgs <- showErrors fatal ("Errors during expansion of binding hooks:\n\n" -- fatal error ++ errmsgs) else do traceInfoOK warnmsgs <- showErrors return (CHSModule (frags' ++ delayedFrags), chi, warnmsgs) where traceInfoExpand = putTraceStr tracePhasesSW ("...expanding binding hooks...\n") traceInfoErr = putTraceStr tracePhasesSW ("...error(s) detected.\n") traceInfoOK = putTraceStr tracePhasesSW ("...successfully completed.\n") expandFrags :: [CHSFrag] -> GB [CHSFrag] expandFrags = liftM concat . mapM expandFrag expandFrag :: CHSFrag -> GB [CHSFrag] expandFrag verb@(CHSVerb _ _ ) = return [verb] expandFrag line@(CHSLine _ ) = return [line] expandFrag (CHSHook h ) = do code <- expandHook h return [CHSVerb code builtinPos] `ifCTExc` return [CHSVerb "** ERROR **" builtinPos] expandFrag (CHSCPP s _ ) = interr $ "GenBind.expandFrag: Left over CHSCPP!\n---\n" ++ s ++ "\n---" expandFrag (CHSC s _ ) = interr $ "GenBind.expandFrag: Left over CHSC!\n---\n" ++ s ++ "\n---" expandFrag (CHSCond alts dft) = do traceInfoCond select alts where select [] = do traceInfoDft dft expandFrags (maybe [] id dft) select ((ide, frags):alts) = do oobj <- findTag ide traceInfoVal ide oobj if isNothing oobj then select alts else -- found right alternative expandFrags frags -- traceInfoCond = traceGenBind "** CPP conditional:\n" traceInfoVal ide oobj = traceGenBind $ identToLexeme ide ++ " is " ++ (if isNothing oobj then "not " else "") ++ "defined.\n" traceInfoDft dft = if isNothing dft then return () else traceGenBind "Choosing else branch.\n" expandHook :: CHSHook -> GB String expandHook (CHSImport qual ide chi _) = do mergeMaps chi return $ "import " ++ (if qual then "qualified " else "") ++ identToLexeme ide expandHook (CHSContext olib oprefix _) = do setContext olib oprefix -- enter context information mapMaybeM_ applyPrefixToNameSpaces oprefix -- use the prefix on name spaces return "" expandHook (CHSType ide pos) = do traceInfoType decl <- findAndChaseDecl ide False True -- no indirection, but shadows ty <- extractSimpleType False pos decl traceInfoDump decl ty when (isVariadic ty) (variadicErr pos (posOf decl)) return $ "(" ++ showExtType ty ++ ")" where traceInfoType = traceGenBind "** Type hook:\n" traceInfoDump decl ty = traceGenBind $ "Declaration\n" ++ show decl ++ "\ntranslates to\n" ++ showExtType ty ++ "\n" expandHook (CHSSizeof ide pos) = do traceInfoSizeof decl <- findAndChaseDecl ide False True -- no indirection, but shadows (size, _) <- sizeAlignOf decl traceInfoDump decl size return $ show (fromIntegral . padBits $ size) where traceInfoSizeof = traceGenBind "** Sizeof hook:\n" traceInfoDump decl size = traceGenBind $ "Size of declaration\n" ++ show decl ++ "\nis " ++ show (fromIntegral . padBits $ size) ++ "\n" expandHook (CHSEnum cide oalias chsTrans oprefix derive _) = do -- get the corresponding C declaration -- enum <- lookupEnum cide True -- smart lookup incl error handling -- -- convert the translation table and generate data type definition code -- gprefix <- getPrefix let prefix = case oprefix of Nothing -> gprefix Just pref -> pref let trans = transTabToTransFun prefix chsTrans hide = identToLexeme . fromMaybe cide $ oalias enumDef enum hide trans (map identToLexeme derive) expandHook hook@(CHSCall isPure isUns (CHSRoot ide) oalias pos) = do traceEnter -- get the corresponding C declaration; raises error if not found or not a -- function; we use shadow identifiers, so the returned identifier is used -- afterwards instead of the original one -- (ObjCO cdecl, ide) <- findFunObj ide True let ideLexeme = identToLexeme ide -- orignal name might have been a shadow hsLexeme = ideLexeme `maybe` identToLexeme $ oalias cdecl' = ide `simplifyDecl` cdecl callImport hook isPure isUns ideLexeme hsLexeme cdecl' pos return hsLexeme where traceEnter = traceGenBind $ "** Call hook for `" ++ identToLexeme ide ++ "':\n" expandHook hook@(CHSCall isPure isUns apath oalias pos) = do traceEnter (decl, offsets) <- accessPath apath ptrTy <- extractSimpleType False pos decl ty <- case ptrTy of PtrET f@(FunET _ _) -> return f _ -> funPtrExpectedErr pos traceValueType ty set_get <- setGet pos CHSGet offsets ptrTy -- get the corresponding C declaration; raises error if not found or not a -- function; we use shadow identifiers, so the returned identifier is used -- afterwards instead of the original one -- -- (ObjCO cdecl, ide) <- findFunObj ide True let ideLexeme = identToLexeme $ apathToIdent apath hsLexeme = ideLexeme `maybe` identToLexeme $ oalias -- cdecl' = ide `simplifyDecl` cdecl args = concat [ " x" ++ show n | n <- [1..numArgs ty] ] callImportDyn hook isPure isUns ideLexeme hsLexeme ty pos return $ "(\\o" ++ args ++ " -> " ++ set_get ++ " o >>= \\f -> " ++ hsLexeme ++ " f" ++ args ++ ")" where traceEnter = traceGenBind $ "** Indirect call hook for `" ++ identToLexeme (apathToIdent apath) ++ "':\n" traceValueType et = traceGenBind $ "Type of accessed value: " ++ showExtType et ++ "\n" expandHook hook@(CHSFun isPure isUns (CHSRoot ide) oalias ctxt parms parm pos) = do traceEnter -- get the corresponding C declaration; raises error if not found or not a -- function; we use shadow identifiers, so the returned identifier is used -- afterwards instead of the original one -- (ObjCO cdecl, cide) <- findFunObj ide True let ideLexeme = identToLexeme ide -- orignal name might have been a shadow hsLexeme = ideLexeme `maybe` identToLexeme $ oalias fiLexeme = hsLexeme ++ "'_" -- *Urgh* - probably unqiue... fiIde = onlyPosIdent nopos fiLexeme cdecl' = cide `simplifyDecl` cdecl callHook = CHSCall isPure isUns (CHSRoot cide) (Just fiIde) pos callImport callHook isPure isUns (identToLexeme cide) fiLexeme cdecl' pos extTy <- extractFunType pos cdecl' True funDef isPure hsLexeme fiLexeme extTy ctxt parms parm Nothing pos where traceEnter = traceGenBind $ "** Fun hook for `" ++ identToLexeme ide ++ "':\n" expandHook hook@(CHSFun isPure isUns apath oalias ctxt parms parm pos) = do traceEnter (decl, offsets) <- accessPath apath ptrTy <- extractSimpleType False pos decl ty <- case ptrTy of PtrET f@(FunET _ _) -> return f _ -> funPtrExpectedErr pos traceValueType ty -- get the corresponding C declaration; raises error if not found or not a -- function; we use shadow identifiers, so the returned identifier is used -- afterwards instead of the original one -- -- (ObjCO cdecl, cide) <- findFunObj ide True let ideLexeme = identToLexeme $ apathToIdent apath hsLexeme = ideLexeme `maybe` identToLexeme $ oalias fiLexeme = hsLexeme ++ "'_" -- *Urgh* - probably unqiue... fiIde = onlyPosIdent nopos fiLexeme -- cdecl' = cide `simplifyDecl` cdecl args = concat [ " x" ++ show n | n <- [1..numArgs ty] ] callHook = CHSCall isPure isUns apath (Just fiIde) pos callImportDyn callHook isPure isUns ideLexeme fiLexeme ty pos set_get <- setGet pos CHSGet offsets ptrTy funDef isPure hsLexeme fiLexeme (FunET ptrTy $ purify ty) ctxt parms parm (Just set_get) pos where -- remove IO from the result type of a function ExtType. necessary -- due to an unexpected interaction with the way funDef works purify (FunET a b) = FunET a (purify b) purify (IOET b) = b purify a = a traceEnter = traceGenBind $ "** Fun hook for `" ++ identToLexeme (apathToIdent apath) ++ "':\n" traceValueType et = traceGenBind $ "Type of accessed value: " ++ showExtType et ++ "\n" expandHook (CHSField access path pos) = do traceInfoField (decl, offsets) <- accessPath path traceDepth offsets ty <- extractSimpleType False pos decl traceValueType ty setGet pos access offsets ty where accessString = case access of CHSGet -> "Get" CHSSet -> "Set" traceInfoField = traceGenBind $ "** " ++ accessString ++ " hook:\n" traceDepth offsets = traceGenBind $ "Depth of access path: " ++ show (length offsets) ++ "\n" traceValueType et = traceGenBind $ "Type of accessed value: " ++ showExtType et ++ "\n" expandHook (CHSPointer isStar cName oalias ptrKind isNewtype oRefType emit pos) = do traceInfoPointer let hsIde = fromMaybe cName oalias hsName = identToLexeme hsIde hsIde `objIs` Pointer ptrKind isNewtype -- register Haskell object -- -- we check for a typedef declaration or tag (struct, union, or enum) -- declOrTag <- lookupDeclOrTag cName True case declOrTag of Left cdecl -> do -- found a typedef declaration cNameFull <- case declaredName cdecl of Just ide -> return ide Nothing -> interr "GenBind.expandHook: Where is the name?" cNameFull `refersToNewDef` ObjCD (TypeCO cdecl) -- assoc needed for chasing traceInfoCName "declaration" cNameFull unless (isStar || isPtrDecl cdecl) $ ptrExpectedErr (posOf cName) (hsType, isFun) <- case oRefType of Nothing -> do cDecl <- chaseDecl cNameFull (not isStar) et <- extractPtrType cDecl traceInfoPtrType et let et' = adjustPtr isStar et when (isVariadic et') (variadicErr pos (posOf cDecl)) return (showExtType et', isFunExtType et') Just hsType -> return (identToLexeme hsType, False) -- FIXME: it is not possible to determine whether `hsType' -- is a function; we would need to extend the syntax to -- allow `... -> fun HSTYPE' to explicitly mark function -- types if this ever becomes important traceInfoHsType hsName hsType pointerDef isStar cNameFull hsName ptrKind isNewtype hsType isFun emit Right tag -> do -- found a tag definition let cNameFull = tagName tag traceInfoCName "tag definition" cNameFull unless isStar $ -- tags need an explicit `*' ptrExpectedErr (posOf cName) let hsType = case oRefType of Nothing -> "()" Just hsType -> identToLexeme hsType traceInfoHsType hsName hsType pointerDef isStar cNameFull hsName ptrKind isNewtype hsType False emit where -- remove a pointer level if the first argument is `False' -- adjustPtr True et = et adjustPtr False (PtrET et) = et adjustPtr False et@(DefinedET _ _) = interr "GenBind.adjustPtr: Can't adjust defined type" adjustPtr _ _ = interr "GenBind.adjustPtr: Where is the Ptr?" -- traceInfoPointer = traceGenBind "** Pointer hook:\n" traceInfoPtrType et = traceGenBind $ "extracted ptr type is `" ++ showExtType et ++ "'\n" traceInfoHsType name ty = traceGenBind $ "associated with Haskell entity `" ++ name ++ "'\nhaving type " ++ ty ++ "\n" traceInfoCName kind ide = traceGenBind $ "found C " ++ kind ++ " for `" ++ identToLexeme ide ++ "'\n" expandHook (CHSClass oclassIde classIde typeIde pos) = do traceInfoClass classIde `objIs` Class oclassIde typeIde -- register Haskell object superClasses <- collectClasses oclassIde Pointer ptrType isNewtype <- queryPointer typeIde when (ptrType == CHSStablePtr) $ illegalStablePtrErr pos classDef pos (identToLexeme classIde) (identToLexeme typeIde) ptrType isNewtype superClasses where -- compile a list of all super classes (the direct super class first) -- collectClasses :: Maybe Ident -> GB [(String, String, HsObject)] collectClasses Nothing = return [] collectClasses (Just ide) = do Class oclassIde typeIde <- queryClass ide ptr <- queryPointer typeIde classes <- collectClasses oclassIde return $ (identToLexeme ide, identToLexeme typeIde, ptr) : classes -- traceInfoClass = traceGenBind $ "** Class hook:\n" -- produce code for an enumeration -- -- * an extra instance declaration is required when any of the enumeration -- constants is explicitly assigned a value in its definition -- -- * the translation function strips prefixes where possible (different -- enumerators maye have different prefixes) -- enumDef :: CEnum -> String -> TransFun -> [String] -> GB String enumDef cenum@(CEnum _ list _) hident trans userDerive = do (list', enumAuto) <- evalTagVals list let enumVals = [(trans ide, cexpr) | (ide, cexpr) <- list'] -- translate defHead = enumHead hident defBody = enumBody (length defHead - 2) enumVals inst = makeDerives (if enumAuto then "Enum" : userDerive else userDerive) ++ if enumAuto then "\n" else "\n" ++ enumInst hident enumVals return $ defHead ++ defBody ++ inst where cpos = posOf cenum -- evalTagVals [] = return ([], True) evalTagVals ((ide, Nothing ):list) = do (list', derived) <- evalTagVals list return ((ide, Nothing):list', derived) evalTagVals ((ide, Just exp):list) = do (list', derived) <- evalTagVals list val <- evalConstCExpr exp case val of IntResult val' -> return ((ide, Just $ CConst (CIntConst val' at1) at2):list', False) FloatResult _ -> illegalConstExprErr (posOf exp) "a float result" where at1 = newAttrsOnlyPos nopos at2 = newAttrsOnlyPos nopos makeDerives [] = "" makeDerives dList = "deriving (" ++ concat (intersperse "," dList) ++")" -- Haskell code for the head of an enumeration definition -- enumHead :: String -> String enumHead ident = "data " ++ ident ++ " = " -- Haskell code for the body of an enumeration definition -- enumBody :: Int -> [(String, Maybe CExpr)] -> String enumBody indent [] = "" enumBody indent ((ide, _):list) = ide ++ "\n" ++ replicate indent ' ' ++ (if null list then "" else "| " ++ enumBody indent list) -- Haskell code for an instance declaration for `Enum' -- -- * the expression of all explicitly specified tag values already have to be -- in normal form, ie, to be an int constant -- -- * enumerations start at 0 and whenever an explicit value is specified, -- following tags are assigned values continuing from the explicitly -- specified one -- enumInst :: String -> [(String, Maybe CExpr)] -> String enumInst ident list = "instance Enum " ++ ident ++ " where\n" ++ fromDef list 0 ++ "\n" ++ toDef list 0 where fromDef [] _ = "" fromDef ((ide, exp):list) n = " fromEnum " ++ ide ++ " = " ++ show' val ++ "\n" ++ fromDef list (val + 1) where val = case exp of Nothing -> n Just (CConst (CIntConst m _) _) -> m Just _ -> interr "GenBind.enumInst: Integer constant expected!" -- show' x = if x < 0 then "(" ++ show x ++ ")" else show x -- toDef [] _ = " toEnum unmatched = error (\"" ++ ident ++ ".toEnum: Cannot match \" ++ show unmatched)\n" toDef ((ide, exp):list) n = " toEnum " ++ show' val ++ " = " ++ ide ++ "\n" ++ toDef list (val + 1) where val = case exp of Nothing -> n Just (CConst (CIntConst m _) _) -> m Just _ -> interr "GenBind.enumInst: Integer constant expected!" -- show' x = if x < 0 then "(" ++ show x ++ ")" else show x -- generate a foreign import declaration that is put into the delayed code -- -- * the C declaration is a simplified declaration of the function that we -- want to import into Haskell land -- callImport :: CHSHook -> Bool -> Bool -> String -> String -> CDecl -> Position -> GB () callImport hook isPure isUns ideLexeme hsLexeme cdecl pos = do -- compute the external type from the declaration, and delay the foreign -- export declaration -- extType <- extractFunType pos cdecl isPure header <- getSwitch headerSB when (isVariadic extType) (variadicErr pos (posOf cdecl)) delayCode hook (foreignImport header ideLexeme hsLexeme isUns extType) traceFunType extType where traceFunType et = traceGenBind $ "Imported function type: " ++ showExtType et ++ "\n" callImportDyn :: CHSHook -> Bool -> Bool -> String -> String -> ExtType -> Position -> GB () callImportDyn hook isPure isUns ideLexeme hsLexeme ty pos = do -- compute the external type from the declaration, and delay the foreign -- export declaration -- when (isVariadic ty) (variadicErr pos pos) -- FIXME? (posOf cdecl)) delayCode hook (foreignImportDyn ideLexeme hsLexeme isUns ty) traceFunType ty where traceFunType et = traceGenBind $ "Imported function type: " ++ showExtType et ++ "\n" -- Haskell code for the foreign import declaration needed by a call hook -- foreignImport :: String -> String -> String -> Bool -> ExtType -> String foreignImport header ident hsIdent isUnsafe ty = "foreign import ccall " ++ safety ++ " " ++ show (header ++ " " ++ ident) ++ "\n " ++ hsIdent ++ " :: " ++ showExtType ty ++ "\n" where safety = if isUnsafe then "unsafe" else "safe" -- Haskell code for the foreign import dynamic declaration needed by a call hook -- foreignImportDyn :: String -> String -> Bool -> ExtType -> String foreignImportDyn ident hsIdent isUnsafe ty = "foreign import ccall " ++ safety ++ " \"dynamic\"\n " ++ hsIdent ++ " :: FunPtr( " ++ showExtType ty ++ " ) -> " ++ showExtType ty ++ "\n" where safety = if isUnsafe then "unsafe" else "safe" -- produce a Haskell function definition for a fun hook -- -- * FIXME: There's an ugly special case in here: to support dynamic fun hooks -- I had to add a special second marshaller for the first argument, -- which, if present, is inserted just before the function call. This -- is probably not the most elegant solution, it's just the only one I -- can up with at the moment. If present, this special marshaller is -- an io action (like 'peek' and unlike 'with'). -- US funDef :: Bool -- pure function? -> String -- name of the new Haskell function -> String -- Haskell name of the foreign imported C function -> ExtType -- simplified declaration of the C function -> Maybe String -- type context of the new Haskell function -> [CHSParm] -- parameter marshalling description -> CHSParm -- result marshalling description -> Maybe String -- optional additional marshaller for first arg -> Position -- source location of the hook -> GB String -- Haskell code in text form funDef isPure hsLexeme fiLexeme extTy octxt parms parm marsh2 pos = do (parms', parm', isImpure) <- addDftMarshaller pos parms parm extTy traceMarsh parms' parm' isImpure let sig = hsLexeme ++ " :: " ++ funTy parms' parm' ++ "\n" marshs = [marshArg i parm | (i, parm) <- zip [1..] parms'] funArgs = [funArg | (funArg, _, _, _, _) <- marshs, funArg /= ""] marshIns = [marshIn | (_, marshIn, _, _, _) <- marshs] callArgs = [callArg | (_, _, cs, _, _) <- marshs, callArg <- cs] marshOuts = [marshOut | (_, _, _, marshOut, _) <- marshs, marshOut /= ""] retArgs = [retArg | (_, _, _, _, retArg) <- marshs, retArg /= ""] funHead = hsLexeme ++ join funArgs ++ " =\n" ++ if isPure && isImpure then " unsafePerformIO $\n" else "" call = if isPure then " let {res = " ++ fiLexeme ++ joinCallArgs ++ "} in\n" else " " ++ fiLexeme ++ joinCallArgs ++ " >>= \\res ->\n" joinCallArgs = case marsh2 of Nothing -> join callArgs Just _ -> join ("b1'" : drop 1 callArgs) mkMarsh2 = case marsh2 of Nothing -> "" Just m -> " " ++ m ++ " " ++ join (take 1 callArgs) ++ " >>= \\b1' ->\n" marshRes = case parm' of CHSParm _ _ twoCVal (Just (_ , CHSVoidArg)) _ -> "" CHSParm _ _ twoCVal (Just (omIde, CHSIOVoidArg)) _ -> " " ++ identToLexeme omIde ++ " res >> \n" CHSParm _ _ twoCVal (Just (omIde, CHSIOArg )) _ -> " " ++ identToLexeme omIde ++ " res >>= \\res' ->\n" CHSParm _ _ twoCVal (Just (omIde, CHSValArg )) _ -> " let {res' = " ++ identToLexeme omIde ++ " res} in\n" CHSParm _ _ _ Nothing _ -> interr "GenBind.funDef: marshRes: no default?" retArgs' = case parm' of CHSParm _ _ _ (Just (_, CHSVoidArg)) _ -> retArgs CHSParm _ _ _ (Just (_, CHSIOVoidArg)) _ -> retArgs _ -> "res'":retArgs ret = "(" ++ concat (intersperse ", " retArgs') ++ ")" funBody = joinLines marshIns ++ mkMarsh2 ++ call ++ joinLines marshOuts ++ marshRes ++ " " ++ (if isImpure || not isPure then "return " else "") ++ ret return $ sig ++ funHead ++ funBody where join = concatMap (' ':) joinLines = concatMap (\s -> " " ++ s ++ "\n") -- -- construct the function type -- -- * specified types appear in the argument and result only if their "in" -- and "out" marshaller, respectively, is not the `void' marshaller -- funTy parms parm = let ctxt = case octxt of Nothing -> "" Just ctxtStr -> ctxtStr ++ " => " argTys = [ty | CHSParm im ty _ _ _ <- parms , notVoid im] resTys = [ty | CHSParm _ ty _ om _ <- parm:parms, notVoid om] resTup = let (lp, rp) = if isPure && length resTys == 1 then ("", "") else ("(", ")") io = if isPure then "" else "IO " in io ++ lp ++ concat (intersperse ", " resTys) ++ rp in ctxt ++ concat (intersperse " -> " (argTys ++ [resTup])) where notVoid Nothing = interr "GenBind.funDef: \ \No default marshaller?" notVoid (Just (_, kind)) = kind /= CHSVoidArg && kind /= CHSIOVoidArg -- -- for an argument marshaller, generate all "in" and "out" marshalling -- code fragments -- marshArg i (CHSParm (Just (imIde, imArgKind)) _ twoCVal (Just (omIde, omArgKind)) _ ) = let a = "a" ++ show i imStr = identToLexeme imIde imApp = imStr ++ " " ++ a funArg = if imArgKind == CHSVoidArg then "" else a inBndr = if twoCVal then "(" ++ a ++ "'1, " ++ a ++ "'2)" else a ++ "'" marshIn = case imArgKind of CHSVoidArg -> imStr ++ " $ \\" ++ inBndr ++ " -> " CHSIOArg -> imApp ++ " $ \\" ++ inBndr ++ " -> " CHSValArg -> "let {" ++ inBndr ++ " = " ++ imApp ++ "} in " callArgs = if twoCVal then [a ++ "'1 ", a ++ "'2"] else [a ++ "'"] omApp = identToLexeme omIde ++ join callArgs outBndr = a ++ "''" marshOut = case omArgKind of CHSVoidArg -> "" CHSIOVoidArg -> omApp ++ ">>" CHSIOArg -> omApp ++ ">>= \\" ++ outBndr ++ " -> " CHSValArg -> "let {" ++ outBndr ++ " = " ++ omApp ++ "} in " retArg = if omArgKind == CHSVoidArg || omArgKind == CHSIOVoidArg then "" else outBndr in (funArg, marshIn, callArgs, marshOut, retArg) marshArg _ _ = interr "GenBind.funDef: Missing default?" -- traceMarsh parms parm isImpure = traceGenBind $ "Marshalling specification including defaults: \n" ++ showParms (parms ++ [parm]) "" ++ " The marshalling is " ++ if isImpure then "impure.\n" else "pure.\n" where showParms [] = id showParms (parm:parms) = showString " " . showCHSParm parm . showChar '\n' . showParms parms -- add default marshallers for "in" and "out" marshalling -- addDftMarshaller :: Position -> [CHSParm] -> CHSParm -> ExtType -> GB ([CHSParm], CHSParm, Bool) addDftMarshaller pos parms parm extTy = do let (resTy, argTys) = splitFunTy extTy (parm' , isImpure1) <- checkResMarsh parm resTy (parms', isImpure2) <- addDft parms argTys return (parms', parm', isImpure1 || isImpure2) where -- the result marshalling may not use an "in" marshaller and can only have -- one C value -- -- * a default marshaller maybe used for "out" marshalling -- checkResMarsh (CHSParm (Just _) _ _ _ pos) _ = resMarshIllegalInErr pos checkResMarsh (CHSParm _ _ True _ pos) _ = resMarshIllegalTwoCValErr pos checkResMarsh (CHSParm _ ty _ omMarsh pos) cTy = do (imMarsh', _ ) <- addDftVoid Nothing (omMarsh', isImpure) <- addDftOut pos omMarsh ty [cTy] return (CHSParm imMarsh' ty False omMarsh' pos, isImpure) -- splitFunTy (FunET UnitET ty ) = splitFunTy ty splitFunTy (FunET ty1 ty2) = let (resTy, argTys) = splitFunTy ty2 in (resTy, ty1:argTys) splitFunTy resTy = (resTy, []) -- -- match Haskell with C arguments (and results) -- addDft ((CHSParm imMarsh hsTy False omMarsh p):parms) (cTy :cTys) = do (imMarsh', isImpureIn ) <- addDftIn p imMarsh hsTy [cTy] (omMarsh', isImpureOut) <- addDftVoid omMarsh (parms' , isImpure ) <- addDft parms cTys return (CHSParm imMarsh' hsTy False omMarsh' p : parms', isImpure || isImpureIn || isImpureOut) addDft ((CHSParm imMarsh hsTy True omMarsh p):parms) (cTy1:cTy2:cTys) = do (imMarsh', isImpureIn ) <- addDftIn p imMarsh hsTy [cTy1, cTy2] (omMarsh', isImpureOut) <- addDftVoid omMarsh (parms' , isImpure ) <- addDft parms cTys return (CHSParm imMarsh' hsTy True omMarsh' p : parms', isImpure || isImpureIn || isImpureOut) addDft [] [] = return ([], False) addDft ((CHSParm _ _ _ _ pos):parms) [] = marshArgMismatchErr pos "This parameter is in excess of the C arguments." addDft [] (_:_) = marshArgMismatchErr pos "Parameter marshallers are missing." -- addDftIn _ imMarsh@(Just (_, kind)) _ _ = return (imMarsh, kind == CHSIOArg) addDftIn pos imMarsh@Nothing hsTy cTys = do marsh <- lookupDftMarshIn hsTy cTys when (isNothing marsh) $ noDftMarshErr pos "\"in\"" hsTy cTys return (marsh, case marsh of {Just (_, kind) -> kind == CHSIOArg}) -- addDftOut _ omMarsh@(Just (_, kind)) _ _ = return (omMarsh, kind == CHSIOArg) addDftOut pos omMarsh@Nothing hsTy cTys = do marsh <- lookupDftMarshOut hsTy cTys when (isNothing marsh) $ noDftMarshErr pos "\"out\"" hsTy cTys return (marsh, case marsh of {Just (_, kind) -> kind == CHSIOArg}) -- -- add void marshaller if no explict one is given -- addDftVoid marsh@(Just (_, kind)) = return (marsh, kind == CHSIOArg) addDftVoid Nothing = do return (Just (noPosIdent "void", CHSVoidArg), False) -- compute from an access path, the declarator finally accessed and the index -- path required for the access -- -- * each element in the index path specifies dereferencing an address and the -- offset to be added to the address before dereferencing -- -- * the returned declaration is already normalised (ie, alias have been -- expanded) -- -- * it may appear as if `t.m' and `t->m' should have different access paths, -- as the latter specifies one more dereferencing; this is certainly true in -- C, but it doesn't apply here, as `t.m' is merely provided for the -- convenience of the interface writer - it is strictly speaking an -- impossible access paths, as in Haskell we always have a pointer to a -- structure, we can never have the structure as a value itself -- accessPath :: CHSAPath -> GB (CDecl, [BitSize]) accessPath (CHSRoot ide) = -- t do decl <- findAndChaseDecl ide False True return (ide `simplifyDecl` decl, [BitSize 0 0]) accessPath (CHSDeref (CHSRoot ide) _) = -- *t do decl <- findAndChaseDecl ide True True return (ide `simplifyDecl` decl, [BitSize 0 0]) accessPath (CHSRef root@(CHSRoot ide1) ide2) = -- t.m do su <- lookupStructUnion ide1 False True (offset, decl') <- refStruct su ide2 adecl <- replaceByAlias decl' return (adecl, [offset]) accessPath (CHSRef (CHSDeref (CHSRoot ide1) _) ide2) = -- t->m do su <- lookupStructUnion ide1 True True (offset, decl') <- refStruct su ide2 adecl <- replaceByAlias decl' return (adecl, [offset]) accessPath (CHSRef path ide) = -- a.m do (decl, offset:offsets) <- accessPath path assertPrimDeclr ide decl su <- structFromDecl (posOf ide) decl (addOffset, decl') <- refStruct su ide adecl <- replaceByAlias decl' return (adecl, offset `addBitSize` addOffset : offsets) where assertPrimDeclr ide (CDecl _ [declr] _) = case declr of (Just (CVarDeclr _ _), _, _) -> return () _ -> structExpectedErr ide accessPath (CHSDeref path pos) = -- *a do (decl, offsets) <- accessPath path decl' <- derefOrErr decl adecl <- replaceByAlias decl' return (adecl, BitSize 0 0 : offsets) where derefOrErr (CDecl specs [declr] at) = case declr of (Just (CPtrDeclr [_] declr at), oinit, oexpr) -> return $ CDecl specs [(Just declr, oinit, oexpr)] at (Just (CPtrDeclr (_:quals) declr at), oinit, oexpr) -> return $ CDecl specs [(Just (CPtrDeclr quals declr at), oinit, oexpr)] at _ -> ptrExpectedErr pos -- replaces a decleration by its alias if any -- -- * the alias inherits any field size specification that the original -- declaration may have -- -- * declaration must have exactly one declarator -- replaceByAlias :: CDecl -> GB CDecl replaceByAlias cdecl@(CDecl _ [(_, _, size)] at) = do ocdecl <- checkForAlias cdecl case ocdecl of Nothing -> return cdecl Just (CDecl specs [(declr, init, _)] at) -> -- form of an alias return $ CDecl specs [(declr, init, size)] at -- given a structure declaration and member name, compute the offset of the -- member in the structure and the declaration of the referenced member -- refStruct :: CStructUnion -> Ident -> GB (BitSize, CDecl) refStruct su ide = do -- get the list of fields and check for our selector -- let (fields, tag) = structMembers su (pre, post) = span (not . flip declNamed ide) fields when (null post) $ unknownFieldErr (posOf su) ide -- -- get sizes of preceding fields and the result type (`pre' are all -- declarators preceding `ide' and the first declarator in `post' defines -- `ide') -- let decl = head post offset <- case tag of CStructTag -> offsetInStruct pre decl tag CUnionTag -> return $ BitSize 0 0 return (offset, decl) -- does the given declarator define the given name? -- declNamed :: CDecl -> Ident -> Bool (CDecl _ [(Nothing , _, _)] _) `declNamed` ide = False (CDecl _ [(Just declr, _, _)] _) `declNamed` ide = declr `declrNamed` ide (CDecl _ [] _) `declNamed` _ = interr "GenBind.declNamed: Abstract declarator in structure!" _ `declNamed` _ = interr "GenBind.declNamed: More than one declarator!" -- Haskell code for writing to or reading from a struct -- setGet :: Position -> CHSAccess -> [BitSize] -> ExtType -> GB String setGet pos access offsets ty = do let pre = case access of CHSSet -> "(\\ptr val -> do {" CHSGet -> "(\\ptr -> do {" body <- setGetBody (reverse offsets) return $ pre ++ body ++ "})" where setGetBody [BitSize offset bitOffset] = do let tyTag = showExtType ty bf <- checkType ty case bf of Nothing -> return $ case access of -- not a bitfield CHSGet -> peekOp offset tyTag CHSSet -> pokeOp offset tyTag "val" --FIXME: must take `bitfieldDirection' into account Just (_, bs) -> return $ case access of -- a bitfield CHSGet -> "val <- " ++ peekOp offset tyTag ++ extractBitfield CHSSet -> "org <- " ++ peekOp offset tyTag ++ insertBitfield ++ pokeOp offset tyTag "val'" where -- we have to be careful here to ensure proper sign extension; -- in particular, shifting right followed by anding a mask is -- *not* sufficient; instead, we exploit in the following that -- `shiftR' performs sign extension -- extractBitfield = "; return $ (val `shiftL` (" ++ bitsPerField ++ " - " ++ show (bs + bitOffset) ++ ")) `shiftR` (" ++ bitsPerField ++ " - " ++ show bs ++ ")" bitsPerField = show $ size CIntPT * 8 -- insertBitfield = "; let {val' = (org .&. " ++ middleMask ++ ") .|. (val `shiftL` " ++ show bitOffset ++ ")}; " middleMask = "fromIntegral (((maxBound::CUInt) `shiftL` " ++ show bs ++ ") `rotateL` " ++ show bitOffset ++ ")" setGetBody (BitSize offset 0 : offsets) = do code <- setGetBody offsets return $ "ptr <- peekByteOff ptr " ++ show offset ++ "; " ++ code setGetBody (BitSize _ _ : _ ) = derefBitfieldErr pos -- -- check that the type can be marshalled and compute extra operations for -- bitfields -- checkType (VarFunET _ ) = variadicErr pos pos checkType (IOET _ ) = interr "GenBind.setGet: Illegal \ \type!" checkType (UnitET ) = voidFieldErr pos checkType (DefinedET _ _ ) = return Nothing-- can't check further checkType (PrimET (CUFieldPT bs)) = return $ Just (False, bs) checkType (PrimET (CSFieldPT bs)) = return $ Just (True , bs) checkType _ = return Nothing -- peekOp off tyTag = "peekByteOff ptr " ++ show off ++ " ::IO " ++ tyTag pokeOp off tyTag var = "pokeByteOff ptr " ++ show off ++ " (" ++ var ++ "::" ++ tyTag ++ ")" -- generate the type definition for a pointer hook and enter the required type -- mapping into the `ptrmap' -- pointerDef :: Bool -- explicit `*' in pointer hook -> Ident -- full C name -> String -- Haskell name -> CHSPtrType -- kind of the pointer -> Bool -- explicit newtype tag -> String -- Haskell type expression of pointer argument -> Bool -- do we have a pointer to a function? -> Bool -- shall we emit code? -> GB String pointerDef isStar cNameFull hsName ptrKind isNewtype hsType isFun emit = do let ptrArg = if isNewtype then hsName -- abstract type else hsType -- concrete type ptrCon = case ptrKind of CHSPtr | isFun -> "FunPtr" _ -> show ptrKind ptrType = ptrCon ++ " (" ++ ptrArg ++ ")" thePtr = (isStar, cNameFull) case ptrKind of CHSForeignPtr -> thePtr `ptrMapsTo` ("Ptr (" ++ ptrArg ++ ")", "Ptr (" ++ ptrArg ++ ")") _ -> thePtr `ptrMapsTo` (hsName, hsName) return $ case (emit, isNewtype) of (False, _) -> "" -- suppress code generation (True , True) -> "newtype " ++ hsName ++ " = " ++ hsName ++ " (" ++ ptrType ++ ")" ++ withForeignFun (True , False) -> "type " ++ hsName ++ " = " ++ ptrType where -- if we have a foreign pointer wrapped into a newtype, provide a -- safe unwrapping function automatically -- withForeignFun | ptrKind == CHSForeignPtr = "\n" ++ "with" ++ hsName ++ " (" ++ hsName ++ " fptr) = withForeignPtr fptr" | otherwise = "" -- generate the class and instance definitions for a class hook -- -- * the pointer type must not be a stable pointer -- -- * the first super class (if present) must be the direct superclass -- -- * all Haskell objects in the superclass list must be pointer objects -- classDef :: Position -- for error messages -> String -- class name -> String -- pointer type name -> CHSPtrType -- type of the pointer -> Bool -- is a newtype? -> [(String, String, HsObject)] -- superclasses -> GB String classDef pos className typeName ptrType isNewtype superClasses = do let toMethodName = case typeName of "" -> interr "GenBind.classDef: \ \Illegal identifier!" c:cs -> toLower c : cs fromMethodName = "from" ++ typeName classDefContext = case superClasses of [] -> "" (superName, _, _):_ -> superName ++ " p => " classDef = "class " ++ classDefContext ++ className ++ " p where\n" ++ " " ++ toMethodName ++ " :: p -> " ++ typeName ++ "\n" ++ " " ++ fromMethodName ++ " :: " ++ typeName ++ " -> p\n" instDef = "instance " ++ className ++ " " ++ typeName ++ " where\n" ++ " " ++ toMethodName ++ " = id\n" ++ " " ++ fromMethodName ++ " = id\n" instDefs <- castInstDefs superClasses return $ classDef ++ instDefs ++ instDef where castInstDefs [] = return "" castInstDefs ((superName, ptrName, Pointer ptrType' isNewtype'):classes) = do unless (ptrType == ptrType') $ pointerTypeMismatchErr pos className superName let toMethodName = case ptrName of "" -> interr "GenBind.classDef: \ \Illegal identifier - 2!" c:cs -> toLower c : cs fromMethodName = "from" ++ ptrName castFun = "cast" ++ show ptrType typeConstr = if isNewtype then typeName ++ " " else "" superConstr = if isNewtype' then ptrName ++ " " else "" instDef = "instance " ++ superName ++ " " ++ typeName ++ " where\n" ++ " " ++ toMethodName ++ " (" ++ typeConstr ++ "p) = " ++ superConstr ++ "(" ++ castFun ++ " p)\n" ++ " " ++ fromMethodName ++ " (" ++ superConstr ++ "p) = " ++ typeConstr ++ "(" ++ castFun ++ " p)\n" instDefs <- castInstDefs classes return $ instDef ++ instDefs -- C code computations -- ------------------- -- the result of a constant expression -- data ConstResult = IntResult Integer | FloatResult Float -- types that may occur in foreign declarations, ie, Haskell land types -- -- * we reprsent C functions with no arguments (ie, the ANSI C `void' -- argument) by `FunET UnitET res' rather than just `res' internally, -- although the latter representation is finally emitted into the binding -- file; this is because we need to know which types are functions (in -- particular, to distinguish between `Ptr a' and `FunPtr a') -- -- * aliased types (`DefinedET') are represented by a string plus their C -- declaration; the latter is for functions interpreting the following -- structure; an aliased type is always a pointer type that is contained in -- the pointer map (and got there either from a .chi or from a pointer hook -- in the same module) -- -- * the representation for pointers does not distinguish between normal, -- function, foreign, and stable pointers; function pointers are identified -- by their argument and foreign and stable pointers are only used -- indirectly, by referring to type names introduced by a `pointer' hook -- data ExtType = FunET ExtType ExtType -- function | IOET ExtType -- operation with side effect | PtrET ExtType -- typed pointer | DefinedET CDecl String -- aliased type | PrimET CPrimType -- basic C type | UnitET -- void | VarFunET ExtType -- variadic function instance Eq ExtType where (FunET t1 t2) == (FunET t1' t2') = t1 == t1' && t2 == t2' (IOET t ) == (IOET t' ) = t == t' (PtrET t ) == (PtrET t' ) = t == t' (DefinedET _ s ) == (DefinedET _ s' ) = s == s' (PrimET t ) == (PrimET t' ) = t == t' (VarFunET t ) == (VarFunET t' ) = t == t' UnitET == UnitET = True -- composite C type -- data CompType = ExtType ExtType -- external type | SUType CStructUnion -- structure or union -- check whether an external type denotes a function type -- isFunExtType :: ExtType -> Bool isFunExtType (FunET _ _) = True isFunExtType (VarFunET _ ) = True isFunExtType (IOET _ ) = True isFunExtType _ = False numArgs :: ExtType -> Int numArgs (FunET _ f) = 1 + numArgs f numArgs _ = 0 -- pretty print an external type -- -- * a previous version of this function attempted to not print unnecessary -- brackets; this however doesn't work consistently due to `DefinedET'; so, -- we give up on the idea (preferring simplicity) -- showExtType :: ExtType -> String showExtType (FunET UnitET res) = showExtType res showExtType (FunET arg res) = "(" ++ showExtType arg ++ " -> " ++ showExtType res ++ ")" showExtType (VarFunET res) = "( ... -> " ++ showExtType res ++ ")" showExtType (IOET t) = "(IO " ++ showExtType t ++ ")" showExtType (PtrET t) = let ptrCon = if isFunExtType t then "FunPtr" else "Ptr" in "(" ++ ptrCon ++ " " ++ showExtType t ++ ")" showExtType (DefinedET _ str) = "(" ++ str ++ ")" showExtType (PrimET CPtrPT) = "(Ptr ())" showExtType (PrimET CFunPtrPT) = "(FunPtr ())" showExtType (PrimET CCharPT) = "CChar" showExtType (PrimET CUCharPT) = "CUChar" showExtType (PrimET CSCharPT) = "CSChar" showExtType (PrimET CIntPT) = "CInt" showExtType (PrimET CShortPT) = "CShort" showExtType (PrimET CLongPT) = "CLong" showExtType (PrimET CLLongPT) = "CLLong" showExtType (PrimET CUIntPT) = "CUInt" showExtType (PrimET CUShortPT) = "CUShort" showExtType (PrimET CULongPT) = "CULong" showExtType (PrimET CULLongPT) = "CULLong" showExtType (PrimET CFloatPT) = "CFloat" showExtType (PrimET CDoublePT) = "CDouble" showExtType (PrimET CLDoublePT) = "CLDouble" showExtType (PrimET (CSFieldPT bs)) = "CInt{-:" ++ show bs ++ "-}" showExtType (PrimET (CUFieldPT bs)) = "CUInt{-:" ++ show bs ++ "-}" showExtType UnitET = "()" -- compute the type of the C function declared by the given C object -- -- * the identifier specifies in which of the declarators we are interested -- -- * if the third argument is `True', the function result should not be -- wrapped into an `IO' type -- -- * the caller has to guarantee that the object does indeed refer to a -- function -- extractFunType :: Position -> CDecl -> Bool -> GB ExtType extractFunType pos cdecl isPure = do -- remove all declarators except that of the function we are processing; -- then, extract the functions arguments and result type (also check that -- the function is not variadic); finally, compute the external type for -- the result -- let (args, resultDecl, variadic) = funResultAndArgs cdecl preResultType <- extractSimpleType True pos resultDecl -- -- we can now add the `IO' monad if this is no pure function -- let protoResultType = if isPure then preResultType else IOET preResultType let resultType = if variadic then VarFunET protoResultType else protoResultType -- -- compute function arguments and create a function type (a function -- prototype with `void' as its single argument declares a nullary -- function) -- argTypes <- mapM (extractSimpleType False pos) args return $ foldr FunET resultType argTypes -- compute a non-struct/union type from the given declaration -- -- * the declaration may have at most one declarator -- -- * C functions are represented as `Ptr (FunEt ...)' or `Addr' if in -- compatibility mode (ie, `--old-ffi=yes') -- extractSimpleType :: Bool -> Position -> CDecl -> GB ExtType extractSimpleType isResult pos cdecl = do traceEnter ct <- extractCompType isResult True cdecl case ct of ExtType et -> return et SUType _ -> illegalStructUnionErr (posOf cdecl) pos where traceEnter = traceGenBind $ "Entering `extractSimpleType' (" ++ (if isResult then "" else "not ") ++ "for a result)...\n" -- compute a Haskell type for a type referenced in a C pointer type -- -- * the declaration may have at most one declarator -- -- * unknown struct/union types are mapped to `()' -- -- * do *not* take aliases into account -- -- * NB: this is by definition not a result type -- extractPtrType :: CDecl -> GB ExtType extractPtrType cdecl = do ct <- extractCompType False False cdecl case ct of ExtType et -> return et SUType _ -> return UnitET -- compute a Haskell type from the given C declaration, where C functions are -- represented by function pointers -- -- * the declaration may have at most one declarator -- -- * all C pointers (including functions) are represented as `Addr' if in -- compatibility mode (--old-ffi) -- -- * typedef'ed types are chased -- -- * the first argument specifies whether the type specifies the result of a -- function (this is only applicable to direct results and not to type -- parameters for pointers that are a result) -- -- * takes the pointer map into account -- -- * IMPORTANT NOTE: `sizeAlignOf' relies on `DefinedET' only being produced -- for pointer types; if this ever changes, we need to -- handle `DefinedET's differently. The problem is that -- entries in the pointer map currently prevent -- `extractCompType' from looking further "into" the -- definition of that pointer. -- extractCompType :: Bool -> Bool -> CDecl -> GB CompType extractCompType isResult usePtrAliases cdecl@(CDecl specs declrs ats) = if length declrs > 1 then interr "GenBind.extractCompType: Too many declarators!" else case declrs of [(Just declr, _, size)] | isPtrDeclr declr -> ptrType declr | isFunDeclr declr -> funType | otherwise -> aliasOrSpecType size [] -> aliasOrSpecType Nothing where -- handle explicit pointer types -- ptrType declr = do tracePtrType let declrs' = dropPtrDeclr declr -- remove indirection cdecl' = CDecl specs [(Just declrs', Nothing, Nothing)] ats oalias = checkForOneAliasName cdecl' -- is only an alias remaining? osu = checkForOneCUName cdecl' oname = if oalias == Nothing then osu else oalias oHsRepr <- case oname of Nothing -> return $ Nothing Just ide -> queryPtr (True, ide) case oHsRepr of Just repr | usePtrAliases -> ptrAlias repr -- got an alias _ -> do -- no alias => recurs ct <- extractCompType False usePtrAliases cdecl' returnX $ case ct of ExtType et -> PtrET et SUType _ -> PtrET UnitET -- -- handle explicit function types -- -- FIXME: we currently regard any functions as being impure (ie, being IO -- functions); is this ever going to be a problem? -- funType = do traceFunType et <- extractFunType (posOf cdecl) cdecl False returnX et -- -- handle all types, which are not obviously pointers or functions -- aliasOrSpecType :: Maybe CExpr -> GB CompType aliasOrSpecType size = do traceAliasOrSpecType size case checkForOneAliasName cdecl of Nothing -> specType (posOf cdecl) specs size Just ide -> do -- this is a typedef alias traceAlias ide oHsRepr <- queryPtr (False, ide) -- check for pointer hook alias case oHsRepr of Just repr | usePtrAliases -> ptrAlias repr -- found a pointer hook alias _ -> do -- skip current alias (only one) cdecl' <- getDeclOf ide let CDecl specs [(declr, init, _)] at = ide `simplifyDecl` cdecl' sdecl = CDecl specs [(declr, init, size)] at -- propagate `size' down (slightly kludgy) extractCompType isResult usePtrAliases sdecl -- -- compute the result for a pointer alias -- ptrAlias (repr1, repr2) = returnX $ DefinedET cdecl (if isResult then repr2 else repr1) -- -- wrap an `ExtType' into a `CompType' -- returnX retval = return $ ExtType retval -- tracePtrType = traceGenBind $ "extractCompType: explicit pointer type\n" traceFunType = traceGenBind $ "extractCompType: explicit function type\n" traceAliasOrSpecType Nothing = traceGenBind $ "extractCompType: checking for alias\n" traceAliasOrSpecType (Just _) = traceGenBind $ "extractCompType: checking for alias of bitfield\n" traceAlias ide = traceGenBind $ "extractCompType: found an alias called `" ++ identToLexeme ide ++ "'\n" -- C to Haskell type mapping described in the DOCU section -- typeMap :: [([CTypeSpec], ExtType)] typeMap = [([void] , UnitET ), ([char] , PrimET CCharPT ), ([unsigned, char] , PrimET CUCharPT ), ([signed, char] , PrimET CSCharPT ), ([signed] , PrimET CIntPT ), ([int] , PrimET CIntPT ), ([signed, int] , PrimET CIntPT ), ([short] , PrimET CShortPT ), ([short, int] , PrimET CShortPT ), ([signed, short] , PrimET CShortPT ), ([signed, short, int] , PrimET CShortPT ), ([long] , PrimET CLongPT ), ([long, int] , PrimET CLongPT ), ([signed, long] , PrimET CLongPT ), ([signed, long, int] , PrimET CLongPT ), ([long, long] , PrimET CLLongPT ), ([long, long, int] , PrimET CLLongPT ), ([signed, long, long] , PrimET CLLongPT ), ([signed, long, long, int] , PrimET CLLongPT ), ([unsigned] , PrimET CUIntPT ), ([unsigned, int] , PrimET CUIntPT ), ([unsigned, short] , PrimET CUShortPT ), ([unsigned, short, int] , PrimET CUShortPT ), ([unsigned, long] , PrimET CULongPT ), ([unsigned, long, int] , PrimET CULongPT ), ([unsigned, long, long] , PrimET CULLongPT ), ([unsigned, long, long, int] , PrimET CULLongPT ), ([float] , PrimET CFloatPT ), ([double] , PrimET CDoublePT ), ([long, double] , PrimET CLDoublePT), ([enum] , PrimET CIntPT )] where void = CVoidType undefined char = CCharType undefined short = CShortType undefined int = CIntType undefined long = CLongType undefined float = CFloatType undefined double = CDoubleType undefined signed = CSignedType undefined unsigned = CUnsigType undefined enum = CEnumType undefined undefined -- compute the complex (external) type determined by a list of type specifiers -- -- * may not be called for a specifier that defines a typedef alias -- specType :: Position -> [CDeclSpec] -> Maybe CExpr -> GB CompType specType cpos specs osize = let tspecs = [ts | CTypeSpec ts <- specs] in case lookupTSpec tspecs typeMap of Just et | isUnsupportedType et -> unsupportedTypeSpecErr cpos | isNothing osize -> return $ ExtType et -- not a bitfield | otherwise -> bitfieldSpec tspecs et osize -- bitfield Nothing -> case tspecs of [CSUType cu _] -> return $ SUType cu -- struct or union [CEnumType _ _] -> return $ ExtType (PrimET CIntPT) -- enum [CTypeDef _ _] -> interr "GenBind.specType: Illegal typedef alias!" _ -> illegalTypeSpecErr cpos where lookupTSpec = lookupBy matches -- isUnsupportedType (PrimET et) = size et == 0 -- can't be a bitfield (yet) isUnsupportedType _ = False -- -- check whether two type specifier lists denote the same type; handles -- types like `long long' correctly, as `deleteBy' removes only the first -- occurrence of the given element -- matches :: [CTypeSpec] -> [CTypeSpec] -> Bool [] `matches` [] = True [] `matches` (_:_) = False (spec:specs) `matches` specs' | any (eqSpec spec) specs' = specs `matches` deleteBy eqSpec spec specs' | otherwise = False -- eqSpec (CVoidType _) (CVoidType _) = True eqSpec (CCharType _) (CCharType _) = True eqSpec (CShortType _) (CShortType _) = True eqSpec (CIntType _) (CIntType _) = True eqSpec (CLongType _) (CLongType _) = True eqSpec (CFloatType _) (CFloatType _) = True eqSpec (CDoubleType _) (CDoubleType _) = True eqSpec (CSignedType _) (CSignedType _) = True eqSpec (CUnsigType _) (CUnsigType _) = True eqSpec (CSUType _ _) (CSUType _ _) = True eqSpec (CEnumType _ _) (CEnumType _ _) = True eqSpec (CTypeDef _ _) (CTypeDef _ _) = True eqSpec _ _ = False -- bitfieldSpec :: [CTypeSpec] -> ExtType -> Maybe CExpr -> GB CompType bitfieldSpec tspecs et (Just sizeExpr) = -- never called with `Nothing' do PlatformSpec {bitfieldIntSignedPS = bitfieldIntSigned} <- getPlatform let pos = posOf sizeExpr sizeResult <- evalConstCExpr sizeExpr case sizeResult of FloatResult _ -> illegalConstExprErr pos "a float result" IntResult size' -> do let size = fromInteger size' case et of PrimET CUIntPT -> returnCT $ CUFieldPT size PrimET CIntPT | [signed] `matches` tspecs || [signed, int] `matches` tspecs -> returnCT $ CSFieldPT size | [int] `matches` tspecs -> returnCT $ if bitfieldIntSigned then CSFieldPT size else CUFieldPT size _ -> illegalFieldSizeErr pos where returnCT = return . ExtType . PrimET -- int = CIntType undefined signed = CSignedType undefined -- offset and size computations -- ---------------------------- -- precise size representation -- -- * this is a pair of a number of octets and a number of bits -- -- * if the number of bits is nonzero, the octet component is aligned by the -- alignment constraint for `CIntPT' (important for accessing bitfields with -- more than 8 bits) -- data BitSize = BitSize Int Int deriving (Eq, Show) -- ordering relation compares in terms of required storage units -- instance Ord BitSize where bs1@(BitSize o1 b1) < bs2@(BitSize o2 b2) = padBits bs1 < padBits bs2 || (o1 == o2 && b1 < b2) bs1 <= bs2 = bs1 < bs2 || bs1 == bs2 -- the <= instance is needed for Ord's compare functions, which is used in -- the defaults for all other members -- add two bit size values -- addBitSize :: BitSize -> BitSize -> BitSize addBitSize (BitSize o1 b1) (BitSize o2 b2) = BitSize (o1 + o2 + overflow) rest where bitsPerBitfield = size CIntPT * 8 (overflow, rest) = (b1 + b2) `divMod` bitsPerBitfield -- multiply a bit size by a constant (gives size of an array) -- -- * not sure if this makes sense if the number of bits is non-zero. -- scaleBitSize :: Int -> BitSize -> BitSize scaleBitSize n (BitSize o1 b1) = BitSize (n * o1 + overflow) rest where bitsPerBitfield = size CIntPT * 8 (overflow, rest) = (n * b1) `divMod` bitsPerBitfield -- pad any storage unit that is partially used by a bitfield -- padBits :: BitSize -> Int padBits (BitSize o 0) = o padBits (BitSize o _) = o + size CIntPT -- compute the offset of the declarator in the second argument when it is -- preceded by the declarators in the first argument -- offsetInStruct :: [CDecl] -> CDecl -> CStructTag -> GB BitSize offsetInStruct [] _ _ = return $ BitSize 0 0 offsetInStruct decls decl tag = do PlatformSpec {bitfieldAlignmentPS = bitfieldAlignment} <- getPlatform (offset, _) <- sizeAlignOfStruct decls tag (_, align) <- sizeAlignOf decl return $ alignOffset offset align bitfieldAlignment -- compute the size and alignment (no padding at the end) of a set of -- declarators from a struct -- sizeAlignOfStruct :: [CDecl] -> CStructTag -> GB (BitSize, Int) sizeAlignOfStruct [] _ = return (BitSize 0 0, 1) sizeAlignOfStruct decls CStructTag = do PlatformSpec {bitfieldAlignmentPS = bitfieldAlignment} <- getPlatform (offset, preAlign) <- sizeAlignOfStruct (init decls) CStructTag (size, align) <- sizeAlignOf (last decls) let sizeOfStruct = alignOffset offset align bitfieldAlignment `addBitSize` size align' = if align > 0 then align else bitfieldAlignment alignOfStruct = preAlign `max` align' return (sizeOfStruct, alignOfStruct) sizeAlignOfStruct decls CUnionTag = do PlatformSpec {bitfieldAlignmentPS = bitfieldAlignment} <- getPlatform (sizes, aligns) <- mapAndUnzipM sizeAlignOf decls let aligns' = [if align > 0 then align else bitfieldAlignment | align <- aligns] return (maximum sizes, maximum aligns') -- compute the size and alignment of the declarators forming a struct -- including any end-of-struct padding that is needed to make the struct ``tile -- in an array'' (K&R A7.4.8) -- sizeAlignOfStructPad :: [CDecl] -> CStructTag -> GB (BitSize, Int) sizeAlignOfStructPad decls tag = do PlatformSpec {bitfieldAlignmentPS = bitfieldAlignment} <- getPlatform (size, align) <- sizeAlignOfStruct decls tag return (alignOffset size align bitfieldAlignment, align) -- compute the size and alignment constraint of a given C declaration -- sizeAlignOf :: CDecl -> GB (BitSize, Int) sizeAlignOfSingle :: CDecl -> GB (BitSize, Int) -- -- * we make use of the assertion that `extractCompType' can only return a -- `DefinedET' when the declaration is a pointer declaration -- * for arrays, alignment is the same as for the base type and the size -- is the size of the base type multiplied by the number of elements. -- FIXME: I'm not sure whether anything of this is guaranteed by ISO C -- and I have no idea what happens when an array-of-bitfield is -- declared. At this time I don't care. -- U.S. 05/2006 -- sizeAlignOf (CDecl dclspec [(Just (CArrDeclr declr _ (Just lexpr) _), init, expr)] attr) = do (bitsize, align) <- sizeAlignOf (CDecl dclspec [(Just declr, init, expr)] attr) IntResult length <- evalConstCExpr lexpr return (fromIntegral length `scaleBitSize` bitsize, align) sizeAlignOf (CDecl _ [(Just (CArrDeclr cdecl _ Nothing _), _, _)] _) = interr "GenBind.sizeAlignOf: array of undeclared size." sizeAlignOf cdecl = sizeAlignOfSingle cdecl sizeAlignOfSingle cdecl = do ct <- extractCompType False False cdecl case ct of ExtType (FunET _ _ ) -> do align <- alignment CFunPtrPT return (bitSize CFunPtrPT, align) ExtType (VarFunET _ ) -> do align <- alignment CFunPtrPT return (bitSize CFunPtrPT, align) ExtType (IOET _ ) -> interr "GenBind.sizeof: Illegal IO type!" ExtType (PtrET t ) | isFunExtType t -> do align <- alignment CFunPtrPT return (bitSize CFunPtrPT, align) | otherwise -> do align <- alignment CPtrPT return (bitSize CPtrPT, align) ExtType (DefinedET _ _ ) -> interr "GenBind.sizeAlignOf: Should never get a defined type" {- OLD: do align <- alignment CPtrPT return (bitSize CPtrPT, align) -- FIXME: The defined type could be a function pointer!!! -} ExtType (PrimET pt ) -> do align <- alignment pt return (bitSize pt, align) ExtType UnitET -> voidFieldErr (posOf cdecl) SUType su -> do let (fields, tag) = structMembers su fields' <- let ide = structName su in if (not . null $ fields) || isNothing ide then return fields else do -- get the real... tag <- findTag (fromJust ide) -- ...definition case tag of Just (StructUnionCT su) -> return (fst . structMembers $ su) _ -> return fields sizeAlignOfStructPad fields' tag where bitSize et | sz < 0 = BitSize 0 (-sz) -- size is in bits | otherwise = BitSize sz 0 where sz = size et -- apply the given alignment constraint at the given offset -- -- * if the alignment constraint is negative or zero, it is the alignment -- constraint for a bitfield -- -- * the third argument gives the platform-specific bitfield alignment -- alignOffset :: BitSize -> Int -> Int -> BitSize alignOffset offset@(BitSize octetOffset bitOffset) align bitfieldAlignment | align > 0 && bitOffset /= 0 = -- close bitfield first alignOffset (BitSize (octetOffset + (bitOffset + 7) `div` 8) 0) align bitfieldAlignment | align > 0 && bitOffset == 0 = -- no bitfields involved BitSize (((octetOffset - 1) `div` align + 1) * align) 0 | bitOffset == 0 -- start a bitfield || overflowingBitfield = -- .. or overflowing bitfield alignOffset offset bitfieldAlignment bitfieldAlignment | otherwise = -- stays in current bitfield offset where bitsPerBitfield = size CIntPT * 8 overflowingBitfield = bitOffset - align >= bitsPerBitfield -- note, `align' is negative -- constant folding -- ---------------- -- evaluate a constant expression -- -- FIXME: this is a bit too simplistic, as the range of expression allowed as -- constant expression varies depending on the context in which the -- constant expression occurs -- evalConstCExpr :: CExpr -> GB ConstResult evalConstCExpr (CComma _ at) = illegalConstExprErr (posOf at) "a comma expression" evalConstCExpr (CAssign _ _ _ at) = illegalConstExprErr (posOf at) "an assignment" evalConstCExpr (CCond b (Just t) e _) = do bv <- evalConstCExpr b case bv of IntResult bvi -> if bvi /= 0 then evalConstCExpr t else evalConstCExpr e FloatResult _ -> illegalConstExprErr (posOf b) "a float result" evalConstCExpr (CBinary op lhs rhs at) = do lhsVal <- evalConstCExpr lhs rhsVal <- evalConstCExpr rhs let (lhsVal', rhsVal') = usualArithConv lhsVal rhsVal applyBin (posOf at) op lhsVal' rhsVal' evalConstCExpr (CCast _ _ _) = todo "GenBind.evalConstCExpr: Casts are not implemented yet." evalConstCExpr (CUnary op arg at) = do argVal <- evalConstCExpr arg applyUnary (posOf at) op argVal evalConstCExpr (CSizeofExpr _ _) = todo "GenBind.evalConstCExpr: sizeof not implemented yet." evalConstCExpr (CSizeofType decl _) = do (size, _) <- sizeAlignOf decl return $ IntResult (fromIntegral . padBits $ size) evalConstCExpr (CAlignofExpr _ _) = todo "GenBind.evalConstCExpr: alignof (GNU C extension) not implemented yet." evalConstCExpr (CAlignofType decl _) = do (_, align) <- sizeAlignOf decl return $ IntResult (fromIntegral align) evalConstCExpr (CIndex _ _ at) = illegalConstExprErr (posOf at) "array indexing" evalConstCExpr (CCall _ _ at) = illegalConstExprErr (posOf at) "function call" evalConstCExpr (CMember _ _ _ at) = illegalConstExprErr (posOf at) "a . or -> operator" evalConstCExpr (CVar ide at) = do (cobj, _) <- findValueObj ide False case cobj of EnumCO ide (CEnum _ enumrs _) -> liftM IntResult $ enumTagValue ide enumrs 0 _ -> todo $ "GenBind.evalConstCExpr: variable names not implemented yet " ++ show (posOf at) where -- FIXME: this is not very nice; instead, CTrav should have some support -- for determining enum tag values (but then, constant folding needs -- to be moved to CTrav, too) -- -- Compute the tag value for `ide' defined in the given enumerator list -- enumTagValue _ [] _ = interr "GenBind.enumTagValue: enumerator not in declaration" enumTagValue ide ((ide', oexpr):enumrs) val = do val' <- case oexpr of Nothing -> return val Just exp -> do val' <- evalConstCExpr exp case val' of IntResult val' -> return val' FloatResult _ -> illegalConstExprErr (posOf exp) "a float result" if ide == ide' then -- found the right enumerator return val' else -- continue down the enumerator list enumTagValue ide enumrs (val' + 1) evalConstCExpr (CConst c _) = evalCConst c evalCConst :: CConst -> GB ConstResult evalCConst (CIntConst i _ ) = return $ IntResult i evalCConst (CCharConst c _ ) = return $ IntResult (toInteger (fromEnum c)) evalCConst (CFloatConst s _ ) = todo "GenBind.evalCConst: Float conversion from literal misses." evalCConst (CStrConst s at) = illegalConstExprErr (posOf at) "a string constant" usualArithConv :: ConstResult -> ConstResult -> (ConstResult, ConstResult) usualArithConv lhs@(FloatResult _) rhs = (lhs, toFloat rhs) usualArithConv lhs rhs@(FloatResult _) = (toFloat lhs, rhs) usualArithConv lhs rhs = (lhs, rhs) toFloat :: ConstResult -> ConstResult toFloat x@(FloatResult _) = x toFloat (IntResult i) = FloatResult . fromIntegral $ i applyBin :: Position -> CBinaryOp -> ConstResult -> ConstResult -> GB ConstResult applyBin cpos CMulOp (IntResult x) (IntResult y) = return $ IntResult (x * y) applyBin cpos CMulOp (FloatResult x) (FloatResult y) = return $ FloatResult (x * y) applyBin cpos CDivOp (IntResult x) (IntResult y) = return $ IntResult (x `div` y) applyBin cpos CDivOp (FloatResult x) (FloatResult y) = return $ FloatResult (x / y) applyBin cpos CRmdOp (IntResult x) (IntResult y) = return$ IntResult (x `mod` y) applyBin cpos CRmdOp (FloatResult x) (FloatResult y) = illegalConstExprErr cpos "a % operator applied to a float" applyBin cpos CAddOp (IntResult x) (IntResult y) = return $ IntResult (x + y) applyBin cpos CAddOp (FloatResult x) (FloatResult y) = return $ FloatResult (x + y) applyBin cpos CSubOp (IntResult x) (IntResult y) = return $ IntResult (x - y) applyBin cpos CSubOp (FloatResult x) (FloatResult y) = return $ FloatResult (x - y) applyBin cpos CShlOp (IntResult x) (IntResult y) = return $ IntResult (x * 2^y) applyBin cpos CShlOp (FloatResult x) (FloatResult y) = illegalConstExprErr cpos "a << operator applied to a float" applyBin cpos CShrOp (IntResult x) (IntResult y) = return $ IntResult (x `div` 2^y) applyBin cpos CShrOp (FloatResult x) (FloatResult y) = illegalConstExprErr cpos "a >> operator applied to a float" applyBin cpos _ (IntResult x) (IntResult y) = todo "GenBind.applyBin: Not yet implemented operator in constant expression." applyBin cpos _ (FloatResult x) (FloatResult y) = todo "GenBind.applyBin: Not yet implemented operator in constant expression." applyBin _ _ _ _ = interr "GenBind.applyBinOp: Illegal combination!" applyUnary :: Position -> CUnaryOp -> ConstResult -> GB ConstResult applyUnary cpos CPreIncOp _ = illegalConstExprErr cpos "a ++ operator" applyUnary cpos CPreDecOp _ = illegalConstExprErr cpos "a -- operator" applyUnary cpos CPostIncOp _ = illegalConstExprErr cpos "a ++ operator" applyUnary cpos CPostDecOp _ = illegalConstExprErr cpos "a -- operator" applyUnary cpos CAdrOp _ = illegalConstExprErr cpos "a & operator" applyUnary cpos CIndOp _ = illegalConstExprErr cpos "a * operator" applyUnary cpos CPlusOp arg = return arg applyUnary cpos CMinOp (IntResult x) = return (IntResult (-x)) applyUnary cpos CMinOp (FloatResult x) = return (FloatResult (-x)) applyUnary cpos CCompOp _ = todo "GenBind.applyUnary: ~ not yet implemented." applyUnary cpos CNegOp (IntResult x) = let r = toInteger . fromEnum $ (x == 0) in return (IntResult r) applyUnary cpos CNegOp (FloatResult _) = illegalConstExprErr cpos "! applied to a float" -- auxilliary functions -- -------------------- -- create an identifier without position information -- noPosIdent :: String -> Ident noPosIdent = onlyPosIdent nopos -- print trace message -- traceGenBind :: String -> GB () traceGenBind = putTraceStr traceGenBindSW -- generic lookup -- lookupBy :: (a -> a -> Bool) -> a -> [(a, b)] -> Maybe b lookupBy eq x = fmap snd . find (eq x . fst) -- maps some monad operation into a `Maybe', discarding the result -- mapMaybeM_ :: Monad m => (a -> m b) -> Maybe a -> m () mapMaybeM_ m Nothing = return () mapMaybeM_ m (Just a) = m a >> return () -- error messages -- -------------- unknownFieldErr :: Position -> Ident -> GB a unknownFieldErr cpos ide = raiseErrorCTExc (posOf ide) ["Unknown member name!", "The structure has no member called `" ++ identToLexeme ide ++ "'. The structure is defined at", show cpos ++ "."] illegalStructUnionErr :: Position -> Position -> GB a illegalStructUnionErr cpos pos = raiseErrorCTExc pos ["Illegal structure or union type!", "There is not automatic support for marshaling of structures and", "unions; the offending type is declared at " ++ show cpos ++ "."] illegalTypeSpecErr :: Position -> GB a illegalTypeSpecErr cpos = raiseErrorCTExc cpos ["Illegal type!", "The type specifiers of this declaration do not form a legal ANSI C(89) \ \type." ] unsupportedTypeSpecErr :: Position -> GB a unsupportedTypeSpecErr cpos = raiseErrorCTExc cpos ["Unsupported type!", "The type specifier of this declaration is not supported by your C \ \compiler." ] variadicErr :: Position -> Position -> GB a variadicErr pos cpos = raiseErrorCTExc pos ["Variadic function!", "Calling variadic functions is not supported by the FFI; the function", "is defined at " ++ show cpos ++ "."] illegalConstExprErr :: Position -> String -> GB a illegalConstExprErr cpos hint = raiseErrorCTExc cpos ["Illegal constant expression!", "Encountered " ++ hint ++ " in a constant expression,", "which ANSI C89 does not permit."] voidFieldErr :: Position -> GB a voidFieldErr cpos = raiseErrorCTExc cpos ["Void field in struct!", "Attempt to access a structure field of type void."] structExpectedErr :: Ident -> GB a structExpectedErr ide = raiseErrorCTExc (posOf ide) ["Expected a structure or union!", "Attempt to access member `" ++ identToLexeme ide ++ "' in something not", "a structure or union."] ptrExpectedErr :: Position -> GB a ptrExpectedErr pos = raiseErrorCTExc pos ["Expected a pointer object!", "Attempt to dereference a non-pointer object or to use it in a `pointer' \ \hook."] funPtrExpectedErr :: Position -> GB a funPtrExpectedErr pos = raiseErrorCTExc pos ["Expected a pointer-to-function object!", "Attempt to use a non-pointer object in a `call' or `fun' hook."] illegalStablePtrErr :: Position -> GB a illegalStablePtrErr pos = raiseErrorCTExc pos ["Illegal use of a stable pointer!", "Class hooks cannot be used for stable pointers."] pointerTypeMismatchErr :: Position -> String -> String -> GB a pointerTypeMismatchErr pos className superName = raiseErrorCTExc pos ["Pointer type mismatch!", "The pointer of the class hook for `" ++ className ++ "' is of a different kind", "than that of the class hook for `" ++ superName ++ "'; this is illegal", "as the latter is defined to be an (indirect) superclass of the former."] illegalFieldSizeErr :: Position -> GB a illegalFieldSizeErr cpos = raiseErrorCTExc cpos ["Illegal field size!", "Only signed and unsigned `int' types may have a size annotation."] derefBitfieldErr :: Position -> GB a derefBitfieldErr pos = raiseErrorCTExc pos ["Illegal dereferencing of a bit field!", "Bit fields cannot be dereferenced."] resMarshIllegalInErr :: Position -> GB a resMarshIllegalInErr pos = raiseErrorCTExc pos ["Malformed result marshalling!", "There may not be an \"in\" marshaller for the result."] resMarshIllegalTwoCValErr :: Position -> GB a resMarshIllegalTwoCValErr pos = raiseErrorCTExc pos ["Malformed result marshalling!", "Two C values (i.e., the `&' symbol) are not allowed for the result."] marshArgMismatchErr :: Position -> String -> GB a marshArgMismatchErr pos reason = raiseErrorCTExc pos ["Function arity mismatch!", reason] noDftMarshErr :: Position -> String -> String -> [ExtType] -> GB a noDftMarshErr pos inOut hsTy cTys = raiseErrorCTExc pos ["Missing " ++ inOut ++ " marshaller!", "There is no default marshaller for this combination of Haskell and \ \C type:", "Haskell type: " ++ hsTy, "C type : " ++ concat (intersperse " " (map showExtType cTys))]