From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Zach Brown <zach@zachbr.io>
Date: Wed, 3 Oct 2018 20:09:18 -0400
Subject: [PATCH] Hook into CB plugin rewrites

Allows us to do fun stuff like rewrite the OBC util fastutil location to
our own relocation. Also lets us rewrite NMS calls for when we're
debugging in an IDE pre-relocate.

diff --git a/pom.xml b/pom.xml
index 7be8342c5007487601487794699b0389e8f7d222..60bf6dd28527f6ffcb59779ec9546030245724ca 100644
--- a/pom.xml
+++ b/pom.xml
@@ -87,7 +87,7 @@
         <dependency>
             <groupId>org.ow2.asm</groupId>
             <artifactId>asm</artifactId>
-            <version>7.3.1</version>
+            <version>8.0.1</version> <!-- Paper -->
             <scope>compile</scope>
         </dependency>
         <dependency>
diff --git a/src/main/java/org/bukkit/craftbukkit/util/Commodore.java b/src/main/java/org/bukkit/craftbukkit/util/Commodore.java
index 9b4a0f0678a7e8e347ef062ad15562484a74452b..4ae41fd2557dcc2a8e31d39ed978b2b26093dd06 100644
--- a/src/main/java/org/bukkit/craftbukkit/util/Commodore.java
+++ b/src/main/java/org/bukkit/craftbukkit/util/Commodore.java
@@ -6,7 +6,9 @@ import java.io.FileOutputStream;
 import java.io.InputStream;
 import java.util.Arrays;
 import java.util.Enumeration;
+import java.util.HashMap;
 import java.util.HashSet;
+import java.util.Map;
 import java.util.Set;
 import java.util.jar.JarEntry;
 import java.util.jar.JarFile;
@@ -20,10 +22,15 @@ import org.bukkit.plugin.AuthorNagException;
 import org.objectweb.asm.ClassReader;
 import org.objectweb.asm.ClassVisitor;
 import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.FieldVisitor;
+import org.objectweb.asm.Handle;
+import org.objectweb.asm.Label;
 import org.objectweb.asm.MethodVisitor;
 import org.objectweb.asm.Opcodes;
 import org.objectweb.asm.Type;
 
+import javax.annotation.Nonnull;
+
 /**
  * This file is imported from Commodore.
  *
@@ -46,6 +53,42 @@ public class Commodore
             "org/bukkit/inventory/ItemStack (I)V setTypeId"
     ) );
 
+    // Paper start - Plugin rewrites
+    private static final Map<String, String> SEARCH_AND_REMOVE = initReplacementsMap();
+    private static Map<String, String> initReplacementsMap()
+    {
+        Map<String, String> getAndRemove = new HashMap<>();
+        // Be wary of maven shade's relocations
+        getAndRemove.put( "org/bukkit/".concat( "craftbukkit/libs/it/unimi/dsi/fastutil/" ), "org/bukkit/".concat( "craftbukkit/libs/" ) ); // Remap fastutil to our location
+
+        if ( Boolean.getBoolean( "debug.rewriteForIde" ) )
+        {
+            // unversion incoming calls for pre-relocate debug work
+            final String NMS_REVISION_PACKAGE = "v1_13_R2/";
+
+            getAndRemove.put( "net/minecraft/".concat( "server/" + NMS_REVISION_PACKAGE ), NMS_REVISION_PACKAGE );
+            getAndRemove.put( "org/bukkit/".concat( "craftbukkit/" + NMS_REVISION_PACKAGE ), NMS_REVISION_PACKAGE );
+        }
+
+        return getAndRemove;
+    }
+
+    @Nonnull
+    private static String getOriginalOrRewrite(@Nonnull String original)
+    {
+        String rewrite = null;
+        for ( Map.Entry<String, String> entry : SEARCH_AND_REMOVE.entrySet() )
+        {
+            if ( original.contains( entry.getKey() ) )
+            {
+                rewrite = original.replace( entry.getValue(), "" );
+            }
+        }
+
+        return rewrite != null ? rewrite : original;
+    }
+    // Paper end
+
     public static void main(String[] args)
     {
         OptionParser parser = new OptionParser();
@@ -128,17 +171,92 @@ public class Commodore
         ClassReader cr = new ClassReader( b );
         ClassWriter cw = new ClassWriter( cr, 0 );
 
-        cr.accept( new ClassVisitor( Opcodes.ASM7, cw )
+        cr.accept( new ClassVisitor( Opcodes.ASM8, cw) // Paper
         {
+            // Paper start - Rewrite plugins
+            @Override
+            public FieldVisitor visitField(int access, String name, String desc, String signature, Object value)
+            {
+                desc = getOriginalOrRewrite( desc );
+                if ( signature != null ) {
+                    signature = getOriginalOrRewrite( signature );
+                }
+
+                return super.visitField( access, name, desc, signature, value) ;
+            }
+            // Paper end
+
             @Override
             public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions)
             {
                 return new MethodVisitor( api, super.visitMethod( access, name, desc, signature, exceptions ) )
                 {
+                    // Paper start - Plugin rewrites
+                    @Override
+                    public void visitInvokeDynamicInsn(String name, String desc, Handle bootstrapMethodHandle, Object... bootstrapMethodArguments)
+                    {
+                        // Paper start - Rewrite plugins
+                        name = getOriginalOrRewrite( name );
+                        if ( desc != null )
+                        {
+                            desc = getOriginalOrRewrite( desc );
+                        }
+                        // Paper end
+
+                        super.visitInvokeDynamicInsn( name, desc, bootstrapMethodHandle, bootstrapMethodArguments );
+                    }
+
+                    @Override
+                    public void visitTypeInsn(int opcode, String type)
+                    {
+                        type = getOriginalOrRewrite( type );
+
+                        super.visitTypeInsn( opcode, type );
+                    }
+
+                    @Override
+                    public void visitFrame(int type, int nLocal, Object[] local, int nStack, Object[] stack) {
+                        for ( int i = 0; i < local.length; i++ )
+                        {
+                            if ( !( local[i] instanceof String ) ) { continue; }
+
+                            local[i] = getOriginalOrRewrite( (String) local[i] );
+                        }
+
+                        for ( int i = 0; i < stack.length; i++ )
+                        {
+                            if ( !( stack[i] instanceof String ) ) { continue; }
+
+                            stack[i] = getOriginalOrRewrite( (String) stack[i] );
+                        }
+
+                        super.visitFrame( type, nLocal, local, nStack, stack );
+                    }
+
+
+
+                    @Override
+                    public void visitLocalVariable(String name, String descriptor, String signature, Label start, Label end, int index)
+                    {
+                        descriptor = getOriginalOrRewrite( descriptor );
+
+                        super.visitLocalVariable( name, descriptor, signature, start, end, index );
+                    }
+                    // Paper end
+
+
 
                     @Override
                     public void visitFieldInsn(int opcode, String owner, String name, String desc)
                     {
+                        // Paper start - Rewrite plugins
+                        owner = getOriginalOrRewrite( owner );
+                        if ( desc != null )
+                        {
+                            desc = getOriginalOrRewrite( desc );
+                        }
+                        // Paper end
+
                         if ( modern )
                         {
                             if ( owner.equals( "org/bukkit/Material" ) )
@@ -237,6 +355,14 @@ public class Commodore
                             return;
                         }
 
+                        // Paper start - Rewrite plugins
+                        owner = getOriginalOrRewrite( owner) ;
+                        if (desc != null)
+                        {
+                            desc = getOriginalOrRewrite(desc);
+                        }
+                        // Paper end
+
                         if ( modern )
                         {
                             if ( owner.equals( "org/bukkit/Material" ) )
