Added blaming of coremods and mods not targetting Java 6

fml/patches/minecraft/net/minecraft/crash/CrashReport.java.patch

@@ -8,3 +8,12 @@
      }
  
      public String func_71501_a()
+@@ -220,6 +221,8 @@
+     {
+         StringBuilder stringbuilder = new StringBuilder();
+         stringbuilder.append("---- Minecraft Crash Report ----\n");
++        net.minecraftforge.fml.common.asm.transformers.BlamingTransformer.onCrash(stringbuilder);
++        net.minecraftforge.fml.relauncher.CoreModManager.onCrash(stringbuilder);
+         stringbuilder.append("// ");
+         stringbuilder.append(func_71503_h());
+         stringbuilder.append("\n\n");

fml/src/main/java/net/minecraftforge/fml/common/FMLCommonHandler.java

@@ -47,6 +47,7 @@ import net.minecraftforge.fml.common.gameevent.PlayerEvent;
 import net.minecraftforge.fml.common.gameevent.TickEvent;
 import net.minecraftforge.fml.common.gameevent.TickEvent.Phase;
 import net.minecraftforge.fml.common.network.NetworkRegistry;
+import net.minecraftforge.fml.relauncher.CoreModManager;
 import net.minecraftforge.fml.relauncher.Side;
 import net.minecraftforge.fml.server.FMLServerHandler;
 
@@ -97,6 +98,28 @@ public class FMLCommonHandler
     private WeakReference<SaveHandler> handlerToCheck;
     private EventBus eventBus = new EventBus();
     private volatile CountDownLatch exitLatch = null;
+
+    private FMLCommonHandler()
+    {
+        registerCrashCallable(new ICrashCallable()
+        {
+            public String call() throws Exception
+            {
+                StringBuilder builder = new StringBuilder();
+                Joiner joiner = Joiner.on("\n  ");
+                for(String coreMod : CoreModManager.getTransformers().keySet())
+                {
+                    builder.append("\n" + coreMod + "\n  ").append(joiner.join(CoreModManager.getTransformers().get(coreMod)));
+                }
+                return builder.toString();
+            }
+
+            public String getLabel()
+            {
+                return "Loaded coremods (and transformers)";
+            }
+        });
+    }
     /**
      * The FML event bus. Subscribe here for FML related events
      *

fml/src/main/java/net/minecraftforge/fml/common/FMLModContainer.java

@@ -27,6 +27,7 @@ import java.util.Set;
 
 import net.minecraftforge.fml.common.Mod.Instance;
 import net.minecraftforge.fml.common.Mod.Metadata;
+import net.minecraftforge.fml.common.asm.transformers.BlamingTransformer;
 import net.minecraftforge.fml.common.discovery.ASMDataTable;
 import net.minecraftforge.fml.common.discovery.ModCandidate;
 import net.minecraftforge.fml.common.discovery.ASMDataTable.ASMData;
@@ -416,6 +417,7 @@ public class FMLModContainer implements ModContainer
     {
         try
         {
+            BlamingTransformer.addClasses(getModId(), candidate.getClassList());
             ModClassLoader modClassLoader = event.getModClassLoader();
             modClassLoader.addFile(source);
             modClassLoader.clearNegativeCacheFor(candidate.getClassList());

fml/src/main/java/net/minecraftforge/fml/common/ModClassLoader.java

@@ -14,19 +14,21 @@ package net.minecraftforge.fml.common;
 
 import java.io.File;
 import java.net.MalformedURLException;
+import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
 import java.net.URLClassLoader;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 
-import org.apache.logging.log4j.Level;
-
 import net.minecraft.launchwrapper.IClassTransformer;
 import net.minecraft.launchwrapper.LaunchClassLoader;
 import net.minecraftforge.fml.common.asm.transformers.ModAPITransformer;
 import net.minecraftforge.fml.common.discovery.ASMDataTable;
 
+import org.apache.logging.log4j.Level;
+
 import com.google.common.collect.ImmutableList;
 
 /**
@@ -59,15 +61,18 @@ public class ModClassLoader extends URLClassLoader
     }
 
     public File[] getParentSources() {
-        List<URL> urls=mainClassLoader.getSources();
-        File[] sources=new File[urls.size()];
         try
         {
-            for (int i = 0; i<urls.size(); i++)
+            List<File> files=new ArrayList<File>();
+            for(URL url : mainClassLoader.getSources())
             {
-                sources[i]=new File(urls.get(i).toURI());
+                URI uri = url.toURI();
+                if(uri.getScheme() == "file")
+                {
+                    files.add(new File(uri));
+                }
             }
-            return sources;
+            return files.toArray(new File[]{});
         }
         catch (URISyntaxException e)
         {

fml/src/main/java/net/minecraftforge/fml/common/asm/ASMTransformerWrapper.java

@@ -0,0 +1,263 @@
+
+
+package net.minecraftforge.fml.common.asm;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLConnection;
+import java.net.URLStreamHandler;
+import java.security.Permission;
+import java.util.Map;
+import java.util.concurrent.ExecutionException;
+
+import net.minecraft.launchwrapper.IClassTransformer;
+import net.minecraft.launchwrapper.LaunchClassLoader;
+
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.FieldVisitor;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.commons.GeneratorAdapter;
+import org.objectweb.asm.commons.Method;
+
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.cache.LoadingCache;
+import com.google.common.collect.Maps;
+
+public class ASMTransformerWrapper
+{
+    private static final Map<String, String> wrapperModMap = Maps.newHashMap();
+    private static final Map<String, String> wrapperParentMap = Maps.newHashMap();
+
+    private static final LoadingCache<String, byte[]> wrapperCache = CacheBuilder.newBuilder()
+        .maximumSize(30)
+        .weakValues()
+        .build(new CacheLoader<String, byte[]>()
+        {
+            public byte[] load(String file) throws Exception
+            {
+                return makeWrapper(file);
+            }
+        });
+
+    private static final URL asmGenRoot;
+    private static boolean injected = false;
+
+    static
+    {
+        try
+        {
+            asmGenRoot = new URL("asmgen", null, -1, "/", new ASMGenHandler());
+        }
+        catch(MalformedURLException e)
+        {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private static class ASMGenHandler extends URLStreamHandler
+    {
+        protected URLConnection openConnection(URL url) throws IOException
+        {
+            String file = url.getFile();
+            if(file.equals("/"))
+            {
+                return new URLConnection(url)
+                {
+                    public void connect() throws IOException
+                    {
+                        throw new UnsupportedOperationException();
+                    }
+                };
+            }
+            if(!file.startsWith("/")) throw new RuntimeException("Malformed URL: " + url);
+            file = file.substring(1);
+            if(wrapperModMap.containsKey(file))
+            {
+                return new ASMGenConnection(url, file);
+            }
+            return null;
+        }
+    }
+
+    private static class ASMGenConnection extends URLConnection
+    {
+        private final String file;
+
+        protected ASMGenConnection(URL url, String file)
+        {
+            super(url);
+            this.file = file;
+        }
+
+        public void connect() throws IOException
+        {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public InputStream getInputStream()
+        {
+            try
+            {
+                return new ByteArrayInputStream(wrapperCache.get(file));
+            }
+            catch (ExecutionException e)
+            {
+                throw new RuntimeException(e);
+            }
+        }
+
+        @Override
+        public Permission getPermission()
+        {
+            return null;
+        }
+    }
+
+    public static String getTransformerWrapper(LaunchClassLoader launchLoader, String parentClass, String coreMod)
+    {
+        if(!injected)
+        {
+            injected = true;
+            launchLoader.addURL(asmGenRoot);
+        }
+
+        String name = getWrapperName(parentClass);
+        String fileName = name.replace('.', '/') + ".class";
+        wrapperModMap.put(fileName, coreMod);
+        wrapperParentMap.put(fileName, parentClass);
+        return name;
+    }
+
+    private static byte[] makeWrapper(String fileName)
+    {
+        if(!wrapperModMap.containsKey(fileName) || !wrapperParentMap.containsKey(fileName) || !fileName.endsWith(".class"))
+        {
+            throw new IllegalArgumentException("makeWrapper called with strange argument: " + fileName);
+        }
+        String name = fileName.substring(0, fileName.length() - ".class".length());
+
+        try
+        {
+            Type wrapper = Type.getType(TransformerWrapper.class);
+
+            ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
+
+            writer.visit(Opcodes.V1_6, Opcodes.ACC_PUBLIC, name, null, wrapper.getInternalName(), null);
+
+            Method m = Method.getMethod("void <init> ()");
+            GeneratorAdapter mg = new GeneratorAdapter(Opcodes.ACC_PUBLIC, m, null, null, writer);
+            mg.loadThis();
+            mg.invokeConstructor(wrapper, m);
+            mg.returnValue();
+            mg.endMethod();
+
+            m = Method.getMethod("java.lang.String getParentClass ()");
+            mg = new GeneratorAdapter(Opcodes.ACC_PROTECTED, m, null, null, writer);
+            mg.push(wrapperParentMap.get(fileName));
+            mg.returnValue();
+            mg.endMethod();
+
+            m = Method.getMethod("java.lang.String getCoreMod ()");
+            mg = new GeneratorAdapter(Opcodes.ACC_PROTECTED, m, null, null, writer);
+            mg.push(wrapperModMap.get(fileName));
+            mg.returnValue();
+            mg.endMethod();
+
+            writer.visitEnd();
+
+            return writer.toByteArray();
+        }
+        catch (Exception e)
+        {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private static String getWrapperName(String parentClass)
+    {
+        return parentClass + "_$Wrapper";
+    }
+
+    private static class WrapperVisitor extends ClassVisitor
+    {
+        private final String name;
+        private final String parentClass;
+
+        public WrapperVisitor(ClassVisitor cv, String name, String parentClass)
+        {
+            super(Opcodes.ASM5, cv);
+            this.name = name.replace('.', '/');
+            this.parentClass = parentClass;
+        }
+
+        @Override
+        public void visit(int version, int access, String name, String signature, String superName, String[] interfaces)
+        {
+            super.visit(version, access, this.name, signature, superName, interfaces);
+        }
+
+        @Override
+        public FieldVisitor visitField(int access, String name, String desc, String signature, Object value)
+        {
+            if(name.equals("parentClass"))
+            {
+                return super.visitField(access, name, desc, signature, parentClass);
+            }
+            return super.visitField(access, name, desc, signature, value);
+        }
+    }
+
+    public static abstract class TransformerWrapper implements IClassTransformer
+    {
+        private final IClassTransformer parent;
+
+        public TransformerWrapper()
+        {
+            try
+            {
+                this.parent = (IClassTransformer)this.getClass().getClassLoader().loadClass(getParentClass()).newInstance();
+            }
+            catch(Exception e)
+            {
+                throw new RuntimeException(e);
+            }
+        }
+
+        public byte[] transform(String name, String transformedName, byte[] basicClass)
+        {
+            try
+            {
+                return parent.transform(name, transformedName, basicClass);
+            }
+            catch(Throwable e)
+            {
+                throw new TransformerException("Exception in class transformer " + parent + " from coremod " + getCoreMod(), e);
+            }
+        }
+
+        @Override
+        public String toString()
+        {
+            return "TransformerWrapper(" + getParentClass() + ", " + getCoreMod() + ")";
+        }
+
+        protected abstract String getParentClass();
+
+        protected abstract String getCoreMod();
+    }
+
+    static class TransformerException extends RuntimeException
+    {
+        public TransformerException(String message, Throwable cause)
+        {
+            super(message, cause);
+        }
+    }
+}

fml/src/main/java/net/minecraftforge/fml/common/asm/transformers/BlamingTransformer.java

@@ -0,0 +1,119 @@
+package net.minecraftforge.fml.common.asm.transformers;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.ListIterator;
+import java.util.Map;
+import java.util.Set;
+import java.util.TreeSet;
+
+import net.minecraft.launchwrapper.IClassTransformer;
+import net.minecraftforge.fml.common.FMLLog;
+
+import org.apache.commons.lang3.JavaVersion;
+import org.apache.commons.lang3.SystemUtils;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.Opcodes;
+
+import com.google.common.collect.ImmutableSet;
+
+public class BlamingTransformer implements IClassTransformer
+{
+    private static final Map<String, String> classMap = new HashMap<String, String>();
+    private static final Set<String> naughtyMods = new HashSet<String>();
+    private static final Set<String> naughtyClasses = new TreeSet<String>();
+    private static final Set<String> orphanNaughtyClasses = new HashSet();
+
+    @Override
+    public byte[] transform(String name, String transformedName, byte[] bytes)
+    {
+        if (bytes == null) { return null; }
+
+        ClassReader classReader = new ClassReader(bytes);
+        VersionVisitor visitor = new VersionVisitor();
+        classReader.accept(visitor, ClassReader.SKIP_CODE | ClassReader.SKIP_DEBUG);
+        return bytes;
+    }
+
+    public static void blame(String modId, String cls)
+    {
+        naughtyClasses.add(cls);
+        naughtyMods.add(modId);
+        FMLLog.severe("Unsupported class format in mod %s: class %s", modId, cls);
+    }
+
+    public static class VersionVisitor extends ClassVisitor
+    {
+        public VersionVisitor()
+        {
+            super(Opcodes.ASM5);
+        }
+
+        @Override
+        public void visit(int version, int access, String name, String signature, String superName, String[] interfaces)
+        {
+            if( (version == Opcodes.V1_8 && !SystemUtils.isJavaVersionAtLeast(JavaVersion.JAVA_1_8)) ||
+                (version == Opcodes.V1_7 && !SystemUtils.isJavaVersionAtLeast(JavaVersion.JAVA_1_7)) )
+            {
+                if(classMap.containsKey(name)) blame(classMap.get(name), name);
+                else orphanNaughtyClasses.add(name);
+            }
+        }
+    }
+
+    private static void checkPendingNaughty()
+    {
+        ImmutableSet.Builder<String> toRemove = ImmutableSet.builder();
+        for(String cls : orphanNaughtyClasses)
+        {
+            if(classMap.containsKey(cls))
+            {
+                String modId = classMap.get(cls);
+                blame(modId, cls);
+                toRemove.add(cls);
+            }
+        }
+        orphanNaughtyClasses.removeAll(toRemove.build());
+    }
+
+    public static void addClasses(String modId, Set<String> classList)
+    {
+        for(String cls : classList)
+        {
+            classMap.put(cls, modId);
+        }
+        checkPendingNaughty();
+    }
+
+    public static void onCrash(StringBuilder builder)
+    {
+        checkPendingNaughty();
+        if(!naughtyClasses.isEmpty())
+        {
+            builder.append("\n*** ATTENTION: detected classes with unsupported format ***\n");
+            builder.append("*** DO NOT SUBMIT THIS CRASH REPORT TO FORGE ***\n\n");
+            if(!naughtyMods.isEmpty())
+            {
+                builder.append("Contact authors of the following mods: \n");
+                for(String modId : naughtyMods)
+                {
+                    builder.append("  ").append(modId).append("\n");
+                }
+            }
+            if(!orphanNaughtyClasses.isEmpty())
+            {
+                builder.append("Unidentified unsupported classes: \n");
+                for(String cls : orphanNaughtyClasses)
+                {
+                    builder.append("  ").append(cls).append("\n");
+                }
+            }
+            builder.append('\n');
+        }
+    }
+}

fml/src/main/java/net/minecraftforge/fml/relauncher/CoreModManager.java

@@ -25,6 +25,7 @@ import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.jar.Attributes;
 import java.util.jar.JarFile;
 
@@ -32,6 +33,7 @@ import net.minecraft.launchwrapper.ITweaker;
 import net.minecraft.launchwrapper.Launch;
 import net.minecraft.launchwrapper.LaunchClassLoader;
 import net.minecraftforge.fml.common.FMLLog;
+import net.minecraftforge.fml.common.asm.ASMTransformerWrapper;
 import net.minecraftforge.fml.common.asm.transformers.ModAccessTransformer;
 import net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker;
 import net.minecraftforge.fml.common.launcher.FMLTweaker;
@@ -50,6 +52,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 import com.google.common.collect.ObjectArrays;
+import com.google.common.collect.Sets;
 import com.google.common.primitives.Ints;
 
 public class CoreModManager {
@@ -58,12 +61,22 @@ public class CoreModManager {
     private static final Attributes.Name MODSIDE = new Attributes.Name("ModSide");
     private static String[] rootPlugins = { "net.minecraftforge.fml.relauncher.FMLCorePlugin", "net.minecraftforge.classloading.FMLForgePlugin" };
     private static List<String> loadedCoremods = Lists.newArrayList();
+    private static Map<String, List<String>> transformers = Maps.newHashMap();
     private static List<FMLPluginWrapper> loadPlugins;
     private static boolean deobfuscatedEnvironment;
     private static FMLTweaker tweaker;
     private static File mcDir;
     private static List<String> reparsedCoremods = Lists.newArrayList();
     private static List<String> accessTransformers = Lists.newArrayList();
+    private static Set<String> rootNames = Sets.newHashSet();
+
+    static
+    {
+        for(String cls : rootPlugins)
+        {
+            rootNames.add(cls.substring(cls.lastIndexOf('.') + 1));
+        }
+    }
 
     private static class FMLPluginWrapper implements ITweaker {
         public final String name;
@@ -98,10 +111,19 @@ public class CoreModManager {
         public void injectIntoClassLoader(LaunchClassLoader classLoader)
         {
             FMLRelaunchLog.fine("Injecting coremod %s {%s} class transformers", name, coreModInstance.getClass().getName());
+            List<String> ts = Lists.newArrayList();
             if (coreModInstance.getASMTransformerClass() != null) for (String transformer : coreModInstance.getASMTransformerClass())
             {
                 FMLRelaunchLog.finer("Registering transformer %s", transformer);
-                classLoader.registerTransformer(transformer);
+                classLoader.registerTransformer(ASMTransformerWrapper.getTransformerWrapper(classLoader, transformer, name));
+                ts.add(transformer);
+            }
+            if(!rootNames.contains(name))
+            {
+                String loc;
+                if(location == null) loc = "unknown";
+                else loc = location.getName();
+                transformers.put(name + " (" + loc + ")", ts);
             }
             FMLRelaunchLog.fine("Injection complete");
 
@@ -405,6 +427,11 @@ public class CoreModManager {
         return loadedCoremods;
     }
 
+    public static Map<String, List<String>> getTransformers()
+    {
+        return transformers;
+    }
+
     public static List<String> getReparseableCoremods()
     {
         return reparsedCoremods;
@@ -609,4 +636,17 @@ public class CoreModManager {
     {
         return accessTransformers;
     }
+
+    public static void onCrash(StringBuilder builder)
+    {
+        if(!loadedCoremods.isEmpty() || !reparsedCoremods.isEmpty())
+        {
+            builder.append("\nWARNING: coremods are present:\n");
+            for(String coreMod : transformers.keySet())
+            {
+                builder.append("  ").append(coreMod).append('\n');
+            }
+            builder.append("Contact their authors BEFORE contacting forge\n\n");
+        }
+    }
 }

fml/src/main/java/net/minecraftforge/fml/relauncher/FMLCorePlugin.java

@@ -20,6 +20,7 @@ public class FMLCorePlugin implements IFMLLoadingPlugin
     public String[] getASMTransformerClass()
     {
         return new String[] {
+                             "net.minecraftforge.fml.common.asm.transformers.BlamingTransformer",
                              "net.minecraftforge.fml.common.asm.transformers.MarkerTransformer",
                              "net.minecraftforge.fml.common.asm.transformers.SideTransformer",
                              "net.minecraftforge.fml.common.asm.transformers.EventSubscriptionTransformer",

fml/src/test/java/net/minecraftforge/fml/debug/FaultyCoreMod.java

@@ -0,0 +1,29 @@
+package net.minecraftforge.fml.debug;
+
+import java.util.Map;
+
+import net.minecraft.launchwrapper.IClassTransformer;
+import net.minecraftforge.fml.relauncher.IFMLLoadingPlugin;
+
+public class FaultyCoreMod implements IFMLLoadingPlugin {
+    public static boolean enabled = false;
+
+    public String[] getASMTransformerClass()
+    {
+        return new String[] { FaultyTransformer.class.getName() };
+    }
+
+    public String getModContainerClass() { return null; }
+    public String getSetupClass() { return null; }
+    public void injectData(Map<String, Object> data) {}
+    public String getAccessTransformerClass() { return null; }
+
+    public static class FaultyTransformer implements IClassTransformer {
+
+        public byte[] transform(String name, String transformedName, byte[] basicClass)
+        {
+            if(enabled && name.equals("net.minecraft.client.gui.GuiMainMenu")) throw new RuntimeException("Faulty transformer test exception");
+            return basicClass;
+        }
+    }
+}

fml/src/test/java/net/minecraftforge/fml/debug/Java8Debug.java

@@ -0,0 +1,26 @@
+/*package net.minecraftforge.fml.debug;
+
+import net.minecraftforge.fml.common.Mod;
+import net.minecraftforge.fml.common.Mod.EventHandler;
+import net.minecraftforge.fml.common.event.FMLInitializationEvent;
+
+@Mod(modid = Java8Debug.MODID, version = Java8Debug.VERSION)
+public class Java8Debug implements ITest
+{
+    public static final String MODID = "Java8Debug";
+    public static final String VERSION = "1.0";
+
+    @EventHandler
+    public void init(FMLInitializationEvent event)
+    {
+        System.out.println("Java8Debug mod loaded");
+    }
+}
+
+interface ITest
+{
+    default int test()
+    {
+        return 42;
+    }
+}*/