(-- * About
-- $about
--
+ --
-- * Internal class file structures
Attribute (..),
FieldType (..),
-- * Misc
HasSignature (..), HasAttributes (..),
NameType (..),
+ fieldNameType, methodNameType,
+ lookupField, lookupMethod,
+ long,
toString,
className,
apsize, arsize, arlist
where
import Control.Monad
+import Control.Monad.Trans (lift)
import Control.Applicative
+import qualified Control.Monad.State as St
import Data.Binary
import Data.Binary.IEEE754
import Data.Binary.Get
-- | Constant pool item
data Constant stage =
CClass (Link stage B.ByteString)
- | CField {refClass :: Link stage B.ByteString, fieldNameType :: Link stage (NameType Field)}
- | CMethod {refClass :: Link stage B.ByteString, nameType :: Link stage (NameType Method)}
- | CIfaceMethod {refClass :: Link stage B.ByteString, nameType :: Link stage (NameType Method)}
+ | CField (Link stage B.ByteString) (Link stage (NameType Field))
+ | CMethod (Link stage B.ByteString) (Link stage (NameType Method))
+ | CIfaceMethod (Link stage B.ByteString) (Link stage (NameType Method))
| CString (Link stage B.ByteString)
| CInteger Word32
| CFloat Float
- | CLong Integer
+ | CLong Word64
| CDouble Double
| CNameType (Link stage B.ByteString) (Link stage B.ByteString)
| CUTF8 {getString :: B.ByteString}
-- | Generic .class file format
data Class stage = Class {
- magic :: Word32, -- ^ Magic value: 0xCAFEBABE
+ magic :: Word32, -- ^ Magic value: 0xCAFEBABE
minorVersion :: Word16,
majorVersion :: Word16,
- constsPoolSize :: Word16, -- ^ Number of items in constants pool
- constsPool :: Pool stage, -- ^ Constants pool itself
- accessFlags :: AccessFlags stage, -- ^ See @JVM.Types.AccessFlag@
- thisClass :: Link stage B.ByteString, -- ^ Constants pool item index for this class
- superClass :: Link stage B.ByteString, -- ^ --/-- for super class, zero for java.lang.Object
- interfacesCount :: Word16, -- ^ Number of implemented interfaces
- interfaces :: [Link stage B.ByteString], -- ^ Constants pool item indexes for implemented interfaces
- classFieldsCount :: Word16, -- ^ Number of class fileds
- classFields :: [Field stage], -- ^ Class fields
- classMethodsCount :: Word16, -- ^ Number of class methods
- classMethods :: [Method stage], -- ^ Class methods
- classAttributesCount :: Word16, -- ^ Number of class attributes
- classAttributes :: Attributes stage -- ^ Class attributes
+ constsPoolSize :: Word16, -- ^ Number of items in constants pool
+ constsPool :: Pool stage, -- ^ Constants pool itself
+ accessFlags :: AccessFlags stage, -- ^ See @JVM.Types.AccessFlag@
+ thisClass :: Link stage B.ByteString, -- ^ Constants pool item index for this class
+ superClass :: Link stage B.ByteString, -- ^ --/-- for super class, zero for java.lang.Object
+ interfacesCount :: Word16, -- ^ Number of implemented interfaces
+ interfaces :: [Link stage B.ByteString], -- ^ Constants pool item indexes for implemented interfaces
+ classFieldsCount :: Word16, -- ^ Number of class fileds
+ classFields :: [Field stage], -- ^ Class fields
+ classMethodsCount :: Word16, -- ^ Number of class methods
+ classMethods :: [Method stage], -- ^ Class methods
+ classAttributesCount :: Word16, -- ^ Number of class attributes
+ classAttributes :: Attributes stage -- ^ Class attributes
}
deriving instance Eq (Class File)
put magic
put minorVersion
put majorVersion
- put constsPoolSize
- forM_ (M.elems constsPool) put
+ putPool constsPool
put accessFlags
put thisClass
put superClass
get = do
magic <- get
+ when (magic /= 0xCAFEBABE) $
+ fail $ "Invalid .class file MAGIC value: " ++ show magic
minor <- get
major <- get
- poolsize <- get
- pool <- replicateM (fromIntegral poolsize - 1) get
- af <- get
+ when (major > 50) $
+ fail $ "Too new .class file format: " ++ show major
+ poolsize <- getWord16be
+ pool <- getPool (poolsize - 1)
+ af <- get
this <- get
super <- get
interfacesCount <- get
ifaces <- replicateM (fromIntegral interfacesCount) get
- classFieldsCount <- get
+ classFieldsCount <- getWord16be
classFields <- replicateM (fromIntegral classFieldsCount) get
classMethodsCount <- get
classMethods <- replicateM (fromIntegral classMethodsCount) get
asCount <- get
as <- replicateM (fromIntegral $ asCount) get
- let pool' = M.fromList $ zip [1..] pool
- return $ Class magic minor major poolsize pool' af this super
+ return $ Class magic minor major poolsize pool af this super
interfacesCount ifaces classFieldsCount classFields
classMethodsCount classMethods asCount (AP as)
return (x: next)
Nothing -> return []
-instance Binary (Constant File) where
- put (CClass i) = putWord8 7 >> put i
- put (CField i j) = putWord8 9 >> put i >> put j
- put (CMethod i j) = putWord8 10 >> put i >> put j
- put (CIfaceMethod i j) = putWord8 11 >> put i >> put j
- put (CString i) = putWord8 8 >> put i
- put (CInteger x) = putWord8 3 >> put x
- put (CFloat x) = putWord8 4 >> putFloat32be x
- put (CLong x) = putWord8 5 >> put x
- put (CDouble x) = putWord8 6 >> putFloat64be x
- put (CNameType i j) = putWord8 12 >> put i >> put j
- put (CUTF8 bs) = do
- putWord8 1
- put (fromIntegral (B.length bs) :: Word16)
- putLazyByteString bs
- put (CUnicode bs) = do
- putWord8 2
- put (fromIntegral (B.length bs) :: Word16)
- putLazyByteString bs
-
- get = do
- !offset <- bytesRead
- tag <- getWord8
- case tag of
- 1 -> do
- l <- get
- bs <- getLazyByteString (fromIntegral (l :: Word16))
- return $ CUTF8 bs
- 2 -> do
- l <- get
- bs <- getLazyByteString (fromIntegral (l :: Word16))
- return $ CUnicode bs
- 3 -> CInteger <$> get
- 4 -> CFloat <$> getFloat32be
- 5 -> CLong <$> get
- 6 -> CDouble <$> getFloat64be
- 7 -> CClass <$> get
- 8 -> CString <$> get
- 9 -> CField <$> get <*> get
- 10 -> CMethod <$> get <*> get
- 11 -> CIfaceMethod <$> get <*> get
- 12 -> CNameType <$> get <*> get
- _ -> fail $ "Unknown constants pool entry tag: " ++ show tag
+long :: Constant stage -> Bool
+long (CLong _) = True
+long (CDouble _) = True
+long _ = False
+
+putPool :: Pool File -> Put
+putPool pool = do
+ let list = M.elems pool
+ d = length $ filter long list
+ putWord16be $ fromIntegral (M.size pool + d + 1)
+ forM_ list putC
+ where
+ putC (CClass i) = putWord8 7 >> put i
+ putC (CField i j) = putWord8 9 >> put i >> put j
+ putC (CMethod i j) = putWord8 10 >> put i >> put j
+ putC (CIfaceMethod i j) = putWord8 11 >> put i >> put j
+ putC (CString i) = putWord8 8 >> put i
+ putC (CInteger x) = putWord8 3 >> put x
+ putC (CFloat x) = putWord8 4 >> putFloat32be x
+ putC (CLong x) = putWord8 5 >> put x
+ putC (CDouble x) = putWord8 6 >> putFloat64be x
+ putC (CNameType i j) = putWord8 12 >> put i >> put j
+ putC (CUTF8 bs) = do
+ putWord8 1
+ put (fromIntegral (B.length bs) :: Word16)
+ putLazyByteString bs
+ putC (CUnicode bs) = do
+ putWord8 2
+ put (fromIntegral (B.length bs) :: Word16)
+ putLazyByteString bs
+
+getPool :: Word16 -> Get (Pool File)
+getPool n = do
+ items <- St.evalStateT go 1
+ return $ M.fromList items
+ where
+ go :: St.StateT Word16 Get [(Word16, Constant File)]
+ go = do
+ i <- St.get
+ if i > n
+ then return []
+ else do
+ c <- lift getC
+ let i' = if long c
+ then i+2
+ else i+1
+ St.put i'
+ next <- go
+ return $ (i,c): next
+
+ getC = do
+ !offset <- bytesRead
+ tag <- getWord8
+ case tag of
+ 1 -> do
+ l <- get
+ bs <- getLazyByteString (fromIntegral (l :: Word16))
+ return $ CUTF8 bs
+ 2 -> do
+ l <- get
+ bs <- getLazyByteString (fromIntegral (l :: Word16))
+ return $ CUnicode bs
+ 3 -> CInteger <$> get
+ 4 -> CFloat <$> getFloat32be
+ 5 -> CLong <$> get
+ 6 -> CDouble <$> getFloat64be
+ 7 -> CClass <$> get
+ 8 -> CString <$> get
+ 9 -> CField <$> get <*> get
+ 10 -> CMethod <$> get <*> get
+ 11 -> CIfaceMethod <$> get <*> get
+ 12 -> CNameType <$> get <*> get
+ _ -> fail $ "Unknown constants pool entry tag: " ++ show tag
+-- _ -> return $ CInteger 0
-- | Class field format
data Field stage = Field {
deriving instance Show (Field File)
deriving instance Show (Field Direct)
+lookupField :: B.ByteString -> Class Direct -> Maybe (Field Direct)
+lookupField name cls = look (classFields cls)
+ where
+ look [] = Nothing
+ look (f:fs)
+ | fieldName f == name = Just f
+ | otherwise = look fs
+
+fieldNameType :: Field Direct -> NameType Field
+fieldNameType f = NameType (fieldName f) (fieldSignature f)
+
instance Binary (Field File) where
put (Field {..}) = do
put fieldAccessFlags
get = do
af <- get
- ni <- get
+ ni <- getWord16be
si <- get
- n <- get
+ n <- getWord16be
as <- replicateM (fromIntegral n) get
return $ Field af ni si n (AP as)
deriving instance Show (Method File)
deriving instance Show (Method Direct)
+methodNameType :: Method Direct -> NameType Method
+methodNameType m = NameType (methodName m) (methodSignature m)
+
+lookupMethod :: B.ByteString -> Class Direct -> Maybe (Method Direct)
+lookupMethod name cls = look (classMethods cls)
+ where
+ look [] = Nothing
+ look (f:fs)
+ | methodName f == name = Just f
+ | otherwise = look fs
+
instance Binary (Method File) where
put (Method {..}) = do
put methodAccessFlags
get = do
offset <- bytesRead
- name <- get
+ name <- getWord16be
len <- getWord32be
value <- getLazyByteString (fromIntegral len)
return $ Attribute name len value