From ccffcf60f83198690c563372c4fe0c1b66efc783 Mon Sep 17 00:00:00 2001
From: Zot201 <erju01@gmail.com>
Date: Thu, 27 Nov 2014 16:02:30 +0900
Subject: [PATCH] Fix Event Bus Access Issues

1) Allow overriding methods in subclass without extra SubscribeEvent annotations
2) Transform event subscribers to have public method/class
---
 .../EventSubscriberTransformer.java           | 74 +++++++++++++++++++
 .../fml/common/eventhandler/EventBus.java     |  2 +-
 .../fml/relauncher/FMLCorePlugin.java         |  1 +
 3 files changed, 76 insertions(+), 1 deletion(-)
 create mode 100644 fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/EventSubscriberTransformer.java

diff --git a/fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/EventSubscriberTransformer.java b/fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/EventSubscriberTransformer.java
new file mode 100644
index 000000000..c910b2402
--- /dev/null
+++ b/fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/EventSubscriberTransformer.java
@@ -0,0 +1,74 @@
+package net.minecraftforge.fml.common.asm.transformers;
+
+import java.lang.reflect.Modifier;
+import java.util.List;
+
+import net.minecraft.launchwrapper.IClassTransformer;
+
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.tree.AnnotationNode;
+import org.objectweb.asm.tree.ClassNode;
+import org.objectweb.asm.tree.MethodNode;
+
+import com.google.common.base.Predicate;
+import com.google.common.collect.Iterables;
+
+public class EventSubscriberTransformer implements IClassTransformer
+{
+    @Override
+    public byte[] transform(String name, String transformedName, byte[] basicClass)
+    {
+        if (basicClass == null) return null;
+
+        ClassNode classNode = new ClassNode();
+        new ClassReader(basicClass).accept(classNode, 0);
+
+        boolean isSubscriber = false;
+
+        for (MethodNode methodNode : classNode.methods)
+        {
+            List<AnnotationNode> anns = methodNode.visibleAnnotations;
+
+            if (anns != null && Iterables.any(anns, SubscribeEventPredicate.INSTANCE))
+            {
+                if (Modifier.isPrivate(methodNode.access))
+                {
+                    String msg = "Cannot apply @SubsribeEvent to private method %s/%s%s";
+                    throw new RuntimeException(String.format(msg, classNode.name, methodNode.name, methodNode.desc));
+                }
+
+                methodNode.access = toPublic(methodNode.access);
+                isSubscriber = true;
+            }
+        }
+
+        if (isSubscriber)
+        {
+            classNode.access = toPublic(classNode.access);
+
+            ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_MAXS);
+            classNode.accept(writer);
+            return writer.toByteArray();
+        }
+
+        return basicClass;
+    }
+
+    private static int toPublic(int access)
+    {
+        return access & ~(Opcodes.ACC_PRIVATE | Opcodes.ACC_PROTECTED) | Opcodes.ACC_PUBLIC;
+    }
+
+    private static class SubscribeEventPredicate implements Predicate<AnnotationNode>
+    {
+        static final SubscribeEventPredicate INSTANCE = new SubscribeEventPredicate();
+
+        @Override
+        public boolean apply(AnnotationNode input)
+        {
+            return input.desc.equals("Lnet/minecraftforge/fml/common/eventhandler/SubscribeEvent;");
+        }
+    }
+}
diff --git a/fml/src/main/java/net/minecraftforge/fml/common/eventhandler/EventBus.java b/fml/src/main/java/net/minecraftforge/fml/common/eventhandler/EventBus.java
index 400c19097..391810d1e 100644
--- a/fml/src/main/java/net/minecraftforge/fml/common/eventhandler/EventBus.java
+++ b/fml/src/main/java/net/minecraftforge/fml/common/eventhandler/EventBus.java
@@ -82,7 +82,7 @@ public class EventBus implements IEventExceptionHandler
                             throw new IllegalArgumentException("Method " + method + " has @SubscribeEvent annotation, but takes a argument that is not an Event " + eventType);
                         }
 
-                        register(eventType, target, method, activeModContainer);
+                        register(eventType, target, real, activeModContainer);
                         break;
                     }
                 }
diff --git a/fml/src/main/java/net/minecraftforge/fml/relauncher/FMLCorePlugin.java b/fml/src/main/java/net/minecraftforge/fml/relauncher/FMLCorePlugin.java
index f41e74ac1..63e61788c 100644
--- a/fml/src/main/java/net/minecraftforge/fml/relauncher/FMLCorePlugin.java
+++ b/fml/src/main/java/net/minecraftforge/fml/relauncher/FMLCorePlugin.java
@@ -23,6 +23,7 @@ public class FMLCorePlugin implements IFMLLoadingPlugin
                              "net.minecraftforge.fml.common.asm.transformers.MarkerTransformer",
                              "net.minecraftforge.fml.common.asm.transformers.SideTransformer",
                              "net.minecraftforge.fml.common.asm.transformers.EventSubscriptionTransformer",
+                             "net.minecraftforge.fml.common.asm.transformers.EventSubscriberTransformer",
                             };
     }