[core] use dex builder to generate resource dummy class (#215)

core/src/main/cpp/external/DexBuilder

@@ -1 +1 @@
-Subproject commit 360465c7c9f8fe6c81fdae17da6895be0884d9f1
+Subproject commit 89988a43bd4bdcd2ed38bf7dc5ab2ea01f5e91df

core/src/main/cpp/main/src/jni/resources_hook.cpp

@@ -20,6 +20,9 @@
 
 #include <jni.h>
 #include <resource_hook.h>
+#include <dex_builder.h>
+#include <art/runtime/thread.h>
+#include <art/runtime/mirror/class.h>
 #include "native_util.h"
 #include "nativehelper/jni_macros.h"
 #include "resources_hook.h"
@@ -43,9 +46,34 @@ namespace lspd {
         return JNI_FALSE;
     }
 
+    LSP_DEF_NATIVE_METHOD(jobject, ResourcesHook, buildDummyClassLoader, jobject parent, jobject resource_super_class, jobject typed_array_super_class) {
+        using namespace startop::dex;
+        static auto in_memory_classloader = (jclass)env->NewGlobalRef(env->FindClass( "dalvik/system/InMemoryDexClassLoader"));
+        static jmethodID initMid = JNI_GetMethodID(env, in_memory_classloader, "<init>",
+                                                   "(Ljava/nio/ByteBuffer;Ljava/lang/ClassLoader;)V");
+        DexBuilder dex_file;
+
+        std::string storage;
+        auto current_thread = art::Thread::Current();
+        ClassBuilder xresource_builder{
+                dex_file.MakeClass("xposed.dummy.XResourcesSuperClass")};
+        xresource_builder.setSuperClass(TypeDescriptor::FromDescriptor(art::mirror::Class(current_thread.DecodeJObject(resource_super_class)).GetDescriptor(&storage)));
+
+        ClassBuilder xtypearray_builder{
+                dex_file.MakeClass("xposed.dummy.XTypedArraySuperClass")};
+        xtypearray_builder.setSuperClass(TypeDescriptor::FromDescriptor(art::mirror::Class(current_thread.DecodeJObject(typed_array_super_class)).GetDescriptor(&storage)));
+
+        slicer::MemView image{dex_file.CreateImage()};
+
+        auto dex_buffer = env->NewDirectByteBuffer(const_cast<void*>(image.ptr()), image.size());
+        return JNI_NewObject(env, in_memory_classloader, initMid,
+                                      dex_buffer, parent);
+    }
+
     static JNINativeMethod gMethods[] = {
             LSP_NATIVE_METHOD(ResourcesHook, initXResourcesNative, "()Z"),
             LSP_NATIVE_METHOD(ResourcesHook, removeFinalFlagNative, "(Ljava/lang/Class;)Z"),
+            LSP_NATIVE_METHOD(ResourcesHook, buildDummyClassLoader, "(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/Class;)Ljava/lang/ClassLoader;"),
     };
 
     void RegisterResourcesHook(JNIEnv *env) {

core/src/main/cpp/main/src/jni/yahfa.cpp

@@ -153,10 +153,8 @@ namespace lspd {
         auto *back_method = backup_builder.Encode();
 
         slicer::MemView image{dex_file.CreateImage()};
-        std::unique_ptr<char[]> buffer = std::make_unique<char[]>(image.size());
-        memcpy(buffer.get(), image.ptr(), image.size());
 
-        auto dex_buffer = env->NewDirectByteBuffer(buffer.get(), image.size());
+        auto dex_buffer = env->NewDirectByteBuffer(const_cast<void*>(image.ptr()), image.size());
         jobject my_cl = JNI_NewObject(env, in_memory_classloader, initMid,
                                       dex_buffer, app_class_loader);
 

core/src/main/java/de/robv/android/xposed/XposedBridge.java

@@ -49,6 +49,7 @@ import de.robv.android.xposed.callbacks.XC_LoadPackage;
 import external.com.android.dx.DexMaker;
 import external.com.android.dx.TypeId;
 import io.github.lsposed.lspd.nativebridge.ModuleLogger;
+import io.github.lsposed.lspd.nativebridge.ResourcesHook;
 
 import static de.robv.android.xposed.XposedHelpers.setObjectField;
 
@@ -97,8 +98,8 @@ public final class XposedBridge {
 		}
 		try {
 			Resources res = Resources.getSystem();
-			Class resClass = res.getClass();
+			Class<?> resClass = res.getClass();
-			Class taClass = TypedArray.class;
+			Class<?> taClass = TypedArray.class;
 			try {
 				TypedArray ta = res.obtainTypedArray(res.getIdentifier(
 						"preloaded_drawables", "array", "android"));
@@ -109,16 +110,20 @@ public final class XposedBridge {
 			}
 			XposedBridge.removeFinalFlagNative(resClass);
 			XposedBridge.removeFinalFlagNative(taClass);
-			DexMaker dexMaker = new DexMaker();
-			dexMaker.declare(TypeId.get("Lxposed/dummy/XResourcesSuperClass;"),
-					"XResourcesSuperClass.java",
-					Modifier.PUBLIC, TypeId.get(resClass));
-			dexMaker.declare(TypeId.get("Lxposed/dummy/XTypedArraySuperClass;"),
-					"XTypedArraySuperClass.java",
-					Modifier.PUBLIC, TypeId.get(taClass));
 			ClassLoader myCL = XposedBridge.class.getClassLoader();
-			dummyClassLoader = new InMemoryDexClassLoader(
+			dummyClassLoader = ResourcesHook.buildDummyClassLoader(myCL.getParent(), resClass, taClass);
-					ByteBuffer.wrap(dexMaker.generate()), myCL.getParent());
+			if (dummyClassLoader == null) {
+				XposedBridge.log("Dexbuilder fails, fallback to dexmaker");
+				DexMaker dexMaker = new DexMaker();
+				dexMaker.declare(TypeId.get("Lxposed/dummy/XResourcesSuperClass;"),
+						"XResourcesSuperClass.java",
+						Modifier.PUBLIC, TypeId.get(resClass));
+				dexMaker.declare(TypeId.get("Lxposed/dummy/XTypedArraySuperClass;"),
+						"XTypedArraySuperClass.java",
+						Modifier.PUBLIC, TypeId.get(taClass));
+				dummyClassLoader = new InMemoryDexClassLoader(
+						ByteBuffer.wrap(dexMaker.generate()), myCL.getParent());
+			}
 			dummyClassLoader.loadClass("xposed.dummy.XResourcesSuperClass");
 			dummyClassLoader.loadClass("xposed.dummy.XTypedArraySuperClass");
 			setObjectField(myCL, "parent", dummyClassLoader);

core/src/main/java/de/robv/android/xposed/XposedInit.java

@@ -142,13 +142,12 @@ public final class XposedInit {
         final ThreadLocal<Object> latestResKey = new ThreadLocal<>();
         final String createResourceMethod;
 
+        classGTLR = android.app.ResourcesManager.class;
+        classResKey = android.content.res.ResourcesKey.class;
+
         if (Build.VERSION.SDK_INT < 30) {
-            classGTLR = Class.forName("android.app.ResourcesManager");
-            classResKey = Class.forName("android.content.res.ResourcesKey");
             createResourceMethod = "getOrCreateResources";
         } else {
-            classGTLR = Class.forName("android.app.ResourcesManager");
-            classResKey = Class.forName("android.content.res.ResourcesKey");
             createResourceMethod = "createResources";
         }
 

core/src/main/java/io/github/lsposed/lspd/nativebridge/ResourcesHook.java

@@ -24,6 +24,7 @@ public class ResourcesHook {
 
     public static native boolean initXResourcesNative();
 
-    public static native boolean removeFinalFlagNative(Class clazz);
+    public static native boolean removeFinalFlagNative(Class<?> clazz);
 
+    public static native ClassLoader buildDummyClassLoader(ClassLoader parent, Class<?> resourceSuperClass, Class<?> typedArraySuperClass);
 }

hiddenapi-stubs/src/main/java/android/app/ResourcesManager.java

@@ -0,0 +1,4 @@
+package android.app;
+
+public class ResourcesManager {
+}

hiddenapi-stubs/src/main/java/android/content/res/ResourcesKey.java

@@ -0,0 +1,4 @@
+package android.content.res;
+
+public class ResourcesKey {
+}