{-# LANGUAGE ForeignFunctionInterface, UnliftedFFITypes, JavaScriptFFI, UnboxedTuples, DeriveDataTypeable, GHCForeignImportPrim, MagicHash, FlexibleInstances, BangPatterns, Rank2Types, CPP #-} {- | Basic interop between Haskell and JavaScript. The principal type here is 'JSVal', which is a lifted type that contains a JavaScript reference. The 'JSVal' type is parameterized with one phantom type, and GHCJS.Types defines several type synonyms for specific variants. The code in this module makes no assumptions about 'JSVal a' types. Operations that can result in a JS exception that can kill a Haskell thread are marked unsafe (for example if the 'JSVal' contains a null or undefined value). There are safe variants where the JS exception is propagated as a Haskell exception, so that it can be handled on the Haskell side. For more specific types, like 'JSArray' or 'JSBool', the code assumes that the contents of the 'JSVal' actually is a JavaScript array or bool value. If it contains an unexpected value, the code can result in exceptions that kill the Haskell thread, even for functions not marked unsafe. The code makes use of `foreign import javascript', enabled with the `JavaScriptFFI` extension, available since GHC 7.8. There are three different safety levels: * unsafe: The imported code is run directly. returning an incorrectly typed value leads to undefined behaviour. JavaScript exceptions in the foreign code kill the Haskell thread. * safe: Returned values are replaced with a default value if they have the wrong type. JavaScript exceptions are caught and propagated as Haskell exceptions ('JSException'), so they can be handled with the standard "Control.Exception" machinery. * interruptible: The import is asynchronous. The calling Haskell thread sleeps until the foreign code calls the `$c` JavaScript function with the result. The thread is in interruptible state while blocked, so it can receive asynchronous exceptions. Unlike the FFI for native code, it's safe to call back into Haskell (`h$run`, `h$runSync`) from foreign code in any of the safety levels. Since JavaScript is single threaded, no Haskell threads can run while the foreign code is running. -} module GHCJS.Foreign.Internal ( JSType(..) , jsTypeOf , JSONType(..) , jsonTypeOf -- , mvarRef , isTruthy , fromJSBool , toJSBool , jsTrue , jsFalse , jsNull , jsUndefined , isNull -- type predicates , isUndefined , isNumber , isObject , isBoolean , isString , isSymbol , isFunction -- internal use, fixme remove {- , toArray , newArray , fromArray , pushArray , indexArray , lengthArray -} -- , newObj -- , js_getProp, js_unsafeGetProp -- , js_setProp, js_unsafeSetProp -- , listProps {- , wrapBuffer, wrapMutableBuffer , byteArrayJSVal, mutableByteArrayJSVal , bufferByteString, byteArrayByteString , unsafeMutableByteArrayByteString -} ) where import GHCJS.Types import qualified GHCJS.Prim as Prim import GHC.Prim import GHC.Exts import Control.Applicative import Control.Concurrent.MVar import Control.DeepSeq (force) import Control.Exception (evaluate, Exception) import Foreign.ForeignPtr.Safe import Foreign.Ptr import Data.Primitive.ByteArray import Data.Typeable (Typeable) import Data.ByteString (ByteString) import Data.ByteString.Unsafe (unsafePackAddressLen) import qualified Data.Text.Array as A import qualified Data.Text as T import qualified Data.Text.Internal as T import qualified Data.Text.Lazy as TL (Text, toStrict, fromStrict) import Unsafe.Coerce -- types returned by JS typeof operator data JSType = Undefined | Object | Boolean | Number | String | Symbol | Function | Other -- ^ implementation dependent deriving (Show, Eq, Ord, Enum, Typeable) -- JSON value type data JSONType = JSONNull | JSONInteger | JSONFloat | JSONBool | JSONString | JSONArray | JSONObject deriving (Show, Eq, Ord, Enum, Typeable) fromJSBool :: JSVal -> Bool fromJSBool b = js_fromBool b {-# INLINE fromJSBool #-} toJSBool :: Bool -> JSVal toJSBool True = jsTrue toJSBool _ = jsFalse {-# INLINE toJSBool #-} jsTrue :: JSVal jsTrue = mkRef (js_true 0#) {-# INLINE jsTrue #-} jsFalse :: JSVal jsFalse = mkRef (js_false 0#) {-# INLINE jsFalse #-} jsNull :: JSVal jsNull = mkRef (js_null 0#) {-# INLINE jsNull #-} jsUndefined :: JSVal jsUndefined = mkRef (js_undefined 0#) {-# INLINE jsUndefined #-} -- check whether a reference is `truthy' in the JavaScript sense isTruthy :: JSVal -> Bool isTruthy b = js_isTruthy b {-# INLINE isTruthy #-} -- isUndefined :: JSVal -> Bool -- isUndefined o = js_isUndefined o -- {-# INLINE isUndefined #-} -- isNull :: JSVal -> Bool -- isNull o = js_isNull o -- {-# INLINE isNull #-} isObject :: JSVal -> Bool isObject o = js_isObject o {-# INLINE isObject #-} isNumber :: JSVal -> Bool isNumber o = js_isNumber o {-# INLINE isNumber #-} isString :: JSVal -> Bool isString o = js_isString o {-# INLINE isString #-} isBoolean :: JSVal -> Bool isBoolean o = js_isBoolean o {-# INLINE isBoolean #-} isFunction :: JSVal -> Bool isFunction o = js_isFunction o {-# INLINE isFunction #-} isSymbol :: JSVal -> Bool isSymbol o = js_isSymbol o {-# INLINE isSymbol #-} {- -- something that we can unsafeCoerce Text from data Text' = Text' {-# UNPACK #-} !Array' -- payload {-# UNPACK #-} !Int -- offset {-# UNPACK #-} !Int -- length data Array' = Array' { aBA :: ByteArray# } data Text'' = Text'' {-# UNPACK #-} !Array'' -- payload {-# UNPACK #-} !Int -- offset {-# UNPACK #-} !Int -- length data Array'' = Array'' { aRef :: Ref# } -- same rep as Ptr Addr#, use this to get just the first field out data Ptr' a = Ptr' ByteArray# Int# ptrToPtr' :: Ptr a -> Ptr' b ptrToPtr' = unsafeCoerce ptr'ToPtr :: Ptr' a -> Ptr b ptr'ToPtr = unsafeCoerce -} {- toArray :: [JSVal a] -> IO (JSArray a) toArray xs = Prim.toJSArray xs {-# INLINE toArray #-} pushArray :: JSVal a -> JSArray a -> IO () pushArray r arr = js_push r arr {-# INLINE pushArray #-} fromArray :: JSArray (JSVal a) -> IO [JSVal a] fromArray a = Prim.fromJSArray a {-# INLINE fromArray #-} lengthArray :: JSArray a -> IO Int lengthArray a = js_length a {-# INLINE lengthArray #-} indexArray :: Int -> JSArray a -> IO (JSVal a) indexArray = js_index {-# INLINE indexArray #-} unsafeIndexArray :: Int -> JSArray a -> IO (JSVal a) unsafeIndexArray = js_unsafeIndex {-# INLINE unsafeIndexArray #-} newArray :: IO (JSArray a) newArray = js_emptyArray {-# INLINE newArray #-} newObj :: IO (JSVal a) newObj = js_emptyObj {-# INLINE newObj #-} listProps :: JSVal a -> IO [JSString] listProps o = fmap unsafeCoerce . Prim.fromJSArray =<< js_listProps o {-# INLINE listProps #-} -} jsTypeOf :: JSVal -> JSType jsTypeOf r = tagToEnum# (js_jsTypeOf r) {-# INLINE jsTypeOf #-} jsonTypeOf :: JSVal -> JSONType jsonTypeOf r = tagToEnum# (js_jsonTypeOf r) {-# INLINE jsonTypeOf #-} {- {- | Convert a JavaScript ArrayBuffer to a 'ByteArray' without copying. Throws a 'JSException' if the 'JSVal' is not an ArrayBuffer. -} wrapBuffer :: Int -- ^ offset from the start in bytes, if this is not a multiple of 8, -- not all types can be read from the ByteArray# -> Int -- ^ length in bytes (use zero or a negative number to use the whole ArrayBuffer) -> JSVal a -- ^ JavaScript ArrayBuffer object -> IO ByteArray -- ^ result wrapBuffer offset size buf = unsafeCoerce <$> js_wrapBuffer offset size buf {-# INLINE wrapBuffer #-} {- | Convert a JavaScript ArrayBuffer to a 'MutableByteArray' without copying. Throws a 'JSException' if the 'JSVal' is not an ArrayBuffer. -} wrapMutableBuffer :: Int -- ^ offset from the start in bytes, if this is not a multiple of 8, -- not all types can be read from / written to the ByteArray# -> Int -- ^ the length in bytes (use zero or a negative number to use the whole ArrayBuffer) -> JSVal a -- ^ JavaScript ArrayBuffer object -> IO (MutableByteArray s) wrapMutableBuffer offset size buf = unsafeCoerce <$> js_wrapBuffer offset size buf {-# INLINE wrapMutableBuffer #-} {- | Get the underlying JS object from a 'ByteArray#'. The object o contains an ArrayBuffer (o.buf) and several typed array views on it (which can have an offset from the start of the buffer and/or a reduced length): * o.i3 : 32 bit signed * o.u8 : 8 bit unsigned * o.u1 : 16 bit unsigned * o.f3 : 32 bit single precision float * o.f6 : 64 bit double precision float * o.dv : a DataView Some of the views will be null if the offset is not a multiple of 8. -} byteArrayJSVal :: ByteArray# -> JSVal a byteArrayJSVal a = unsafeCoerce (ByteArray a) {-# INLINE byteArrayJSVal #-} {- | Get the underlying JS object from a 'MutableByteArray#'. The object o contains an ArrayBuffer (o.buf) and several typed array views on it (which can have an offset from the start of the buffer and/or a reduced length): * o.i3 : 32 bit signed * o.u8 : 8 bit unsigned * o.u1 : 16 bit unsigned * o.f3 : 32 bit single precision float * o.f6 : 64 bit double precision float * o.dv : a DataView Some of the views will be null if the offset is not a multiple of 8. -} mutableByteArrayJSVal :: MutableByteArray# s -> JSVal a mutableByteArrayJSVal a = unsafeCoerce (MutableByteArray a) {-# INLINE mutableByteArrayJSVal #-} foreign import javascript safe "h$wrapBuffer($3, true, $1, $2)" js_wrapBuffer :: Int -> Int -> JSVal a -> IO (JSVal ()) {- | Convert an ArrayBuffer to a strict 'ByteString' this wraps the original buffer, without copying. Use 'byteArrayByteString' if you already have a wrapped buffer -} bufferByteString :: Int -- ^ offset from the start in bytes -> Int -- ^ length in bytes (use zero or a negative number to get the whole ArrayBuffer) -> JSVal a -> IO ByteString bufferByteString offset length buf = do (ByteArray ba) <- wrapBuffer offset length buf byteArrayByteString ba {- | Pack a ByteArray# primitive into a ByteString without copying the buffer. This is unsafe in native code -} byteArrayByteString :: ByteArray# -> IO ByteString byteArrayByteString arr = #ifdef ghcjs_HOST_OS let ba = ByteArray arr !(Addr a) = byteArrayContents ba in unsafePackAddressLen (sizeofByteArray ba) a #else error "GHCJS.Foreign.byteArrayToByteString: not JS" #endif {- | Pack a MutableByteArray# primitive into a 'ByteString' without copying. The byte array shouldn't be modified after converting. This is unsafe in native code -} unsafeMutableByteArrayByteString :: MutableByteArray# s -> IO ByteString unsafeMutableByteArrayByteString arr = #ifdef ghcjs_HOST_OS let ba = MutableByteArray arr !(Addr a) = mutableByteArrayContents ba in unsafePackAddressLen (sizeofMutableByteArray ba) a #else error "GHCJS.Foreign.unsafeMutableByteArrayToByteString: no JS" #endif -} -- ----------------------------------------------------------------------------- foreign import javascript unsafe "$r = $1===true;" js_fromBool :: JSVal -> Bool foreign import javascript unsafe "$1 ? true : false" js_isTruthy :: JSVal -> Bool foreign import javascript unsafe "$r = true;" js_true :: Int# -> Ref# foreign import javascript unsafe "$r = false;" js_false :: Int# -> Ref# foreign import javascript unsafe "$r = null;" js_null :: Int# -> Ref# foreign import javascript unsafe "$r = undefined;" js_undefined :: Int# -> Ref# -- foreign import javascript unsafe "$r = [];" js_emptyArray :: IO (JSArray a) -- foreign import javascript unsafe "$r = {};" js_emptyObj :: IO (JSVal a) --foreign import javascript unsafe "$3[$1] = $2;" -- js_unsafeWriteArray :: Int# -> JSVal a -> JSArray b -> IO () -- foreign import javascript unsafe "h$fromArray" -- js_fromArray :: JSArray a -> IO Ref# -- [a] --foreign import javascript safe "$2.push($1)" -- js_push :: JSVal a -> JSArray a -> IO () --foreign import javascript safe "$1.length" js_length :: JSArray a -> IO Int --foreign import javascript safe "$2[$1]" -- js_index :: Int -> JSArray a -> IO (JSVal a) --foreign import javascript unsafe "$2[$1]" -- js_unsafeIndex :: Int -> JSArray a -> IO (JSVal a) foreign import javascript unsafe "$2[$1]" js_unsafeGetProp :: JSString -> JSVal -> IO JSVal foreign import javascript unsafe "$3[$1] = $2" js_unsafeSetProp :: JSString -> JSVal -> JSVal -> IO () {- foreign import javascript safe "h$listProps($1)" js_listProps :: JSVal a -> IO (JSArray JSString) -} foreign import javascript unsafe "h$jsTypeOf($1)" js_jsTypeOf :: JSVal -> Int# foreign import javascript unsafe "h$jsonTypeOf($1)" js_jsonTypeOf :: JSVal -> Int# -- foreign import javascript unsafe "h$listToArray" -- js_toArray :: Any -> IO (JSArray a) -- foreign import javascript unsafe "$1 === null" -- js_isNull :: JSVal a -> Bool -- foreign import javascript unsafe "h$isUndefined" js_isUndefined :: JSVal a -> Bool foreign import javascript unsafe "h$isObject" js_isObject :: JSVal -> Bool foreign import javascript unsafe "h$isBoolean" js_isBoolean :: JSVal -> Bool foreign import javascript unsafe "h$isNumber" js_isNumber :: JSVal -> Bool foreign import javascript unsafe "h$isString" js_isString :: JSVal -> Bool foreign import javascript unsafe "h$isSymbol" js_isSymbol :: JSVal -> Bool foreign import javascript unsafe "h$isFunction" js_isFunction :: JSVal -> Bool