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/src/main/java/org/bukkit/craftbukkit/util/Commodore.java b/src/main/java/org/bukkit/craftbukkit/util/Commodore.java
index 79b386af9eb2450b0a8abe3342bc53d3f0b86fd9..58df23162aed12f3058b5e0921a9e30b89f56a10 100644
--- a/src/main/java/org/bukkit/craftbukkit/util/Commodore.java
+++ b/src/main/java/org/bukkit/craftbukkit/util/Commodore.java
@@ -12,6 +12,7 @@ import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Enumeration;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
@@ -22,6 +23,7 @@ import java.util.jar.JarEntry;
 import java.util.jar.JarFile;
 import java.util.jar.JarOutputStream;
 import java.util.zip.ZipEntry;
+import javax.annotation.Nonnull;
 import joptsimple.OptionParser;
 import joptsimple.OptionSet;
 import joptsimple.OptionSpec;
@@ -126,6 +128,40 @@ public class Commodore {
         return this.reroutes;
     }
 
+    // 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
+
+        final java.util.jar.Manifest manifest = io.papermc.paper.util.JarManifests.manifest(Commodore.class);
+        if (Boolean.getBoolean( "debug.rewriteForIde") && manifest != null)
+        {
+            // unversion incoming calls for pre-relocate debug work
+            final String NMS_REVISION_PACKAGE = "v" + manifest.getMainAttributes().getValue("CraftBukkit-Package-Version") + "/";
+
+            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 - Plugin rewrites
+
     public static void main(String[] args) {
         OptionParser parser = new OptionParser();
         OptionSpec<File> inputFlag = parser.acceptsAll(Arrays.asList("i", "input")).withRequiredArg().ofType(File.class).required();
@@ -281,9 +317,49 @@ public class Commodore {
                 }
 
                 return new MethodVisitor(this.api, super.visitMethod(access, name, desc, signature, exceptions)) {
+                    // Paper start - Plugin rewrites
+                    @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 - Plugin rewrites
 
                     @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
                         name = FieldRename.rename(pluginVersion, owner, name);
 
                         if (modern) {
@@ -396,6 +472,13 @@ public class Commodore {
                             return;
                         }
 
+                        // Paper start - Rewrite plugins
+                        owner = getOriginalOrRewrite(owner) ;
+                        if (desc != null) {
+                            desc = getOriginalOrRewrite(desc);
+                        }
+                        // Paper end - Rewrite plugins
+
                         if (modern) {
                             if (owner.equals("org/bukkit/Material") || (instantiatedMethodType != null && instantiatedMethodType.getDescriptor().startsWith("(Lorg/bukkit/Material;)"))) {
                                 switch (name) {
@@ -492,6 +575,13 @@ public class Commodore {
 
                     @Override
                     public void visitLdcInsn(Object value) {
+                        // Paper start
+                        if (value instanceof Type type) {
+                            if (type.getSort() == Type.OBJECT || type.getSort() == Type.ARRAY) {
+                                value = Type.getType(getOriginalOrRewrite(type.getDescriptor()));
+                            }
+                        }
+                        // Paper end
                         if (value instanceof String && ((String) value).equals("com.mysql.jdbc.Driver")) {
                             super.visitLdcInsn("com.mysql.cj.jdbc.Driver");
                             return;
@@ -502,6 +592,14 @@ public class Commodore {
 
                     @Override
                     public void visitInvokeDynamicInsn(String name, String descriptor, Handle bootstrapMethodHandle, Object... bootstrapMethodArguments) {
+                        // Paper start - Rewrite plugins
+                        name = getOriginalOrRewrite(name);
+                        if (descriptor != null) {
+                            descriptor = getOriginalOrRewrite(descriptor);
+                        }
+                        final String fName = name;
+                        final String fDescriptor = descriptor;
+                        // Paper end - Rewrite plugins
                         if (bootstrapMethodHandle.getOwner().equals("java/lang/invoke/LambdaMetafactory")
                                 && bootstrapMethodHandle.getName().equals("metafactory") && bootstrapMethodArguments.length == 3) {
                             Type samMethodType = (Type) bootstrapMethodArguments[0];
@@ -518,7 +616,7 @@ public class Commodore {
                                 methodArgs.add(new Handle(newOpcode, newOwner, newName, newDescription, newItf));
                                 methodArgs.add(newInstantiated);
 
-                                super.visitInvokeDynamicInsn(name, descriptor, bootstrapMethodHandle, methodArgs.toArray(Object[]::new));
+                                super.visitInvokeDynamicInsn(fName, fDescriptor, bootstrapMethodHandle, methodArgs.toArray(Object[]::new)); // Paper - use final local vars
                             }, implMethod.getTag(), implMethod.getOwner(), implMethod.getName(), implMethod.getDesc(), implMethod.isInterface(), samMethodType, instantiatedMethodType);
                             return;
                         }
@@ -569,6 +667,12 @@ public class Commodore {
 
             @Override
             public FieldVisitor visitField(int access, String name, String descriptor, String signature, Object value) {
+                // Paper start - Rewrite plugins
+                descriptor = getOriginalOrRewrite(descriptor);
+                if ( signature != null ) {
+                    signature = getOriginalOrRewrite(signature);
+                }
+                // Paper end
                 return new FieldVisitor(this.api, super.visitField(access, name, descriptor, signature, value)) {
                     @Override
                     public AnnotationVisitor visitAnnotation(String descriptor, boolean visible) {