Generalize FoxLoaderPatches.patchBuildConfig() to make a catto happy.

Author: Fox2Code

patching/generate.gradle

@@ -73,9 +73,14 @@ static void generateBuildConfig0(File buildConfigSrc, Project project) {
         printStream.println("// Auto generated class, do not modify.")
         printStream.println("package com.fox2code.foxloader.launcher;")
         printStream.println()
+        printStream.println("import com.fox2code.foxloader.patching.TransformerUtils;")
+        printStream.println("import org.objectweb.asm.tree.ClassNode;")
+        printStream.println()
         printStream.println("/**")
         printStream.println(" * Class used to get info about FoxLoader, unlike regular final constants,")
         printStream.println(" * the one in this class won't get inlined due to a FoxLoader specific ASM hack.")
+        printStream.println(" *")
+        printStream.println(" * @see TransformerUtils#deInlineFieldConstants(ClassNode, boolean)")
         printStream.println(" */")
         printStream.println("public final class BuildConfig {")
         printStream.println("    private BuildConfig() {}")

patching/src/main/java/com/fox2code/foxloader/patching/FoxLoaderPatches.java

@@ -68,6 +68,7 @@ public static void patchFoxLoaderFinalJar(File foxloaderJar) throws IOException
         if (!foxloaderJar.renameTo(backup)) {
             throw new IOException("Failed to rename loader jar");
         }
+        boolean patchedBuildConfig = false;
         try (ZipInputStream zipInputStream = new ZipInputStream(
                 new BufferedInputStream(Files.newInputStream(backup.toPath())));
              ZipOutputStream zipOutputStream = new ZipOutputStream(
@@ -83,6 +84,7 @@ public static void patchFoxLoaderFinalJar(File foxloaderJar) throws IOException
                     ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
                     IOUtils.copy(zipInputStream, byteArrayOutputStream);
                     zipOutputStream.write(patchBuildConfig(byteArrayOutputStream.toByteArray()));
+                    patchedBuildConfig = true;
                 } else {
                     IOUtils.copy(zipInputStream, zipOutputStream);
                 }
@@ -91,6 +93,9 @@ public static void patchFoxLoaderFinalJar(File foxloaderJar) throws IOException
             }
             zipOutputStream.finish();
         }
+        if (!patchedBuildConfig) {
+            throw new IOException("Patching BuildConfig failed.");
+        }
         if (backup.exists() && !backup.delete()) {
             throw new IOException("Failed to delete backup jar");
         }
@@ -99,40 +104,10 @@ public static void patchFoxLoaderFinalJar(File foxloaderJar) throws IOException
     private static byte[] patchBuildConfig(byte[] buildConfig) {
         ClassNode classNode = new ClassNode();
         new ClassReader(buildConfig).accept(classNode, 0);
-        if (TransformerUtils.findMethod(classNode, "<clinit>") != null) {
-            throw new RuntimeException("<clinit>()V detected in BuildConfig!");
-        }
-        MethodNode clInit = new MethodNode(ACC_STATIC, "<clinit>", "()V", null, null);
-        for (FieldNode fieldNode : classNode.fields) {
-            if (fieldNode.access != (ACC_PUBLIC | ACC_STATIC | ACC_FINAL)) {
-                throw new RuntimeException("Invalid field access: " + fieldNode.access);
-            }
-            AbstractInsnNode constInsn;
-            switch (fieldNode.desc) {
-                case "Ljava/lang/String;":
-                    constInsn = new LdcInsnNode(fieldNode.value);
-                    break;
-                case "I":
-                case "Z":
-                    if (fieldNode.value instanceof Integer) {
-                        constInsn = TransformerUtils.getNumberInsn((Integer) fieldNode.value);
-                    } else if (fieldNode.value instanceof Boolean) {
-                        constInsn = TransformerUtils.getBooleanInsn((Boolean) fieldNode.value);
-                    } else {
-                        throw new RuntimeException("WTF???");
-                    }
-                    break;
-                default:
-                    throw new RuntimeException("Unsupported desc: \"" + fieldNode.desc + "\"");
-            }
-            fieldNode.value = null;
-            clInit.instructions.add(constInsn);
-            clInit.instructions.add(new FieldInsnNode(PUTSTATIC,
-                    "com/fox2code/foxloader/launcher/BuildConfig",
-                    fieldNode.name, fieldNode.desc));
+        TransformerUtils.deInlineFieldConstants(classNode, true);
+        if (classNode.methods.size() != 2) {
+            throw new RuntimeException("WHAT? " + classNode.methods.size());
         }
-        clInit.instructions.add(new InsnNode(RETURN));
-        classNode.methods.add(clInit);
         ClassWriter classWriter = new ClassWriter(ClassWriter.COMPUTE_MAXS);
         classNode.accept(classWriter);
         return classWriter.toByteArray();

patching/src/main/java/com/fox2code/foxloader/patching/TransformerUtils.java

@@ -1024,4 +1024,61 @@ public static AbstractInsnNode getConsumingInstruction(InsnList insnList, Abstra
         }
         return null;
     }
+
+    public static void deInlineFieldConstants(ClassNode classNode) {
+        deInlineFieldConstants(classNode, false);
+    }
+
+    public static void deInlineFieldConstants(ClassNode classNode, boolean strict) {
+        InsnList addedNodes = new InsnList();
+        for (FieldNode fieldNode : classNode.fields) {
+            if ((fieldNode.access & (Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC | Opcodes.ACC_FINAL)) !=
+                    (Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC | Opcodes.ACC_FINAL)) {
+                if (strict) {
+                    throw new RuntimeException("Invalid field access: " + fieldNode.access);
+                }
+                continue;
+            }
+            if (fieldNode.value == null) {
+                continue;
+            }
+            AbstractInsnNode constInsn;
+            switch (fieldNode.desc) {
+                case "Ljava/lang/String;":
+                    constInsn = new LdcInsnNode(fieldNode.value);
+                    break;
+                case "I":
+                case "Z":
+                case "S":
+                case "B":
+                case "C":
+                    if (fieldNode.value instanceof Integer) {
+                        constInsn = TransformerUtils.getNumberInsn((Integer) fieldNode.value);
+                    } else if (fieldNode.value instanceof Boolean) {
+                        constInsn = TransformerUtils.getBooleanInsn((Boolean) fieldNode.value);
+                    } else {
+                        throw new RuntimeException("WTF???");
+                    }
+                    break;
+                default:
+                    throw new RuntimeException("Unsupported desc: \"" + fieldNode.desc + "\"");
+            }
+            fieldNode.value = null;
+            addedNodes.add(constInsn);
+            addedNodes.add(new FieldInsnNode(Opcodes.PUTSTATIC,
+                    classNode.name, fieldNode.name, fieldNode.desc));
+        }
+        if (addedNodes.getFirst() == null) {
+            return;
+        }
+        MethodNode clInit = TransformerUtils.findMethod(classNode, "<clinit>");
+        if (clInit == null) {
+            clInit = new MethodNode(Opcodes.ACC_STATIC, "<clinit>", "()V", null, null);
+            clInit.instructions.add(new InsnNode(Opcodes.RETURN));
+            classNode.methods.add(clInit);
+        } else if (strict) {
+            throw new RuntimeException("<clinit>()V detected in BuildConfig!");
+        }
+        insertToEndOfCode(clInit, addedNodes);
+    }
 }