From a82f30acddd8106364e8f22051cc26899028841f Mon Sep 17 00:00:00 2001
From: Bernhard Urban <lewurm@gmail.com>
Date: Mon, 23 Apr 2012 22:38:00 +0200
Subject: [PATCH] classpool: copy field members refs from superclass

---
 Makefile           |  2 ++
 Mate/ClassPool.hs  | 27 +++++++++++++++++----------
 Mate/Types.hs      |  2 +-
 tests/Static1.java |  8 ++++++--
 tests/Static2.java |  2 +-
 tests/Static3.java | 26 ++++++++++++++++++++++++++
 6 files changed, 53 insertions(+), 14 deletions(-)
 create mode 100644 tests/Static3.java

diff --git a/Makefile b/Makefile
index 82ff90a..4346835 100644
--- a/Makefile
+++ b/Makefile
@@ -32,6 +32,8 @@ test: mate $(CLASS_FILES)
 	@printf "should be:  0x%08x\n" 0x33
 	./$< tests/Static2 | grep mainresult
 	@printf "should be:  0x%08x\n" 0x55
+	./$< tests/Static3 | grep mainresult
+	@printf "should be:  0x%08x\n" 0x6dd
 
 %.class: %.java
 	$(JAVAC) $<
diff --git a/Mate/ClassPool.hs b/Mate/ClassPool.hs
index eb97e21..b1618ed 100644
--- a/Mate/ClassPool.hs
+++ b/Mate/ClassPool.hs
@@ -30,6 +30,8 @@ getClassFile path = do
   (ClassInfo _ cfile _ _) <- getClassInfo path
   return cfile
 
+-- TODO(bernhard): I think we don't need that anymore. also remove fieldbase
+--                 entry in ClassInfo
 getFieldBase :: B.ByteString -> IO (CUInt)
 getFieldBase path = do
   (ClassInfo _ _ fs _) <- getClassInfo path
@@ -48,24 +50,29 @@ getFieldAddr from ptr_trapmap = do
   let sfi = trapmap M.! w32_from
   case sfi of
     (SFI (StaticFieldInfo cls field)) -> do
-      off <- getFieldOffset cls field
-      base <- getFieldBase cls
-      return $ base + off
+      getFieldOffset cls field
     _ -> error $ "getFieldAddr: no trapInfo. abort"
 
 loadClass :: B.ByteString -> IO ClassInfo
 loadClass path = do
-  ptr_classmap <- get_classmap
-  class_map <- ptr2classmap ptr_classmap
+  printf "loadClass: \"%s\"\n" $ toString path
   let rpath = toString $ path `B.append` ".class"
   cfile <- parseClassFile rpath
-  printf "class fieldlength: %d\n" $ classFieldsCount cfile
+  superclass <- case (path /= "java/lang/Object") of
+      True -> do
+        sc <- loadClass $ superClass cfile
+        return $ Just $ sc
+      False -> return $ Nothing
+  class_map <- get_classmap >>= ptr2classmap
   -- TODO(bernhard): correct sizes. int only atm
   let filteredfields = filter (S.member ACC_STATIC . fieldAccessFlags) (classFields cfile)
-  let fm = zipWith (\x y -> (fieldName y, x)) [0,4..] filteredfields
-  let fieldmap = M.fromList fm
-  fieldbase <- mallocBytes ((fromIntegral $ M.size fieldmap) * 4)
-  putStrLn $ "fieldmap: " ++ (show fieldmap)
+  fieldbase <- mallocBytes ((fromIntegral $ length filteredfields) * 4)
+  let i_fb = fromIntegral $ ptrToIntPtr $ fieldbase
+  let fm = zipWith (\x y -> (fieldName y, x + i_fb)) [0,4..] filteredfields
+  let sc_fm = case superclass of Just x -> clFieldMap x; Nothing -> M.empty
+  -- new fields "overwrite" old ones, if they have the same name
+  let fieldmap = (M.fromList fm) `M.union` sc_fm
+  printf "fieldmap: %s @ %s\n" (show fieldmap) (toString path)
   let new_ci = ClassInfo path cfile fieldbase fieldmap
   let class_map' = M.insert path new_ci class_map
   classmap2ptr class_map' >>= set_classmap
diff --git a/Mate/Types.hs b/Mate/Types.hs
index 6918084..130c293 100644
--- a/Mate/Types.hs
+++ b/Mate/Types.hs
@@ -49,7 +49,7 @@ type FieldMap = M.Map B.ByteString Int32
 data ClassInfo = ClassInfo {
   clName :: B.ByteString,
   clFile :: Class Resolved,
-  clField :: Ptr Int32,
+  clFieldBase :: Ptr Int32,
   clFieldMap :: FieldMap }
 
 data MethodInfo = MethodInfo {
diff --git a/tests/Static1.java b/tests/Static1.java
index 726da7d..74ca4fd 100644
--- a/tests/Static1.java
+++ b/tests/Static1.java
@@ -5,12 +5,16 @@ public class Static1 {
 	public static int y;
 
 	public static void main(String []args) {
+		setNumbers();
+		addNumbers(); // 0x33
+	}
+
+	public static void setNumbers() {
 		Static1.x = 0x11;
 		Static1.y = 0x22;
-		addnumbers();
 	}
 
-	public static int addnumbers() {
+	public static int addNumbers() {
 		return Static1.x + Static1.y;
 	}
 }
diff --git a/tests/Static2.java b/tests/Static2.java
index 874360d..cfc85dc 100644
--- a/tests/Static2.java
+++ b/tests/Static2.java
@@ -11,6 +11,6 @@ public class Static2 {
 		// in Static2 as in Static1
 		Static1.x = 0x33;
 		Static1.y = 0x22;
-		Static1.addnumbers();
+		Static1.addNumbers();
 	}
 }
diff --git a/tests/Static3.java b/tests/Static3.java
new file mode 100644
index 0000000..a5a732c
--- /dev/null
+++ b/tests/Static3.java
@@ -0,0 +1,26 @@
+package tests;
+
+public class Static3 extends Static1 {
+	public static int z;
+	public static int sum;
+	public static void main(String []args) {
+		sum = 0;
+		Static3.x = 0x111;
+		Static3.y = 0x555;
+		sum += Static1.addNumbers(); // 0x666
+		Static1.setNumbers();
+		sum += Static1.addNumbers(); // 0x33
+		Static3.z = 0x11;
+		sum += Static3.addNumbers(); // 0x44
+		getSum(); // 0x666 + 0x33 + 0x44 = 0x6dd
+		// System.out.printf("%x\n", getSum());
+	}
+
+	public static int getSum() {
+		return sum;
+	}
+
+	public static int addNumbers() {
+		return x + y + z;
+	}
+}
-- 
2.25.1