From 5b22a60984269e171bdd7d21a8f32ad978c7b5de Mon Sep 17 00:00:00 2001
From: Raven Szewczyk <git@eigenraven.me>
Date: Sun, 30 Jun 2024 10:02:32 +0100
Subject: [PATCH] Fix infinite loop in forge if patch parsing fails, fix compat
 with upgraded apache-compress

---
 .../lwjgl3ify/redirects/JarInputStream.java   | 18 ++++++++
 .../lwjgl3ify/redirects/Pack200.java          |  3 ++
 .../transformers/ForgePatchTransformer.java   | 44 ++++++++++++++++++-
 3 files changed, 63 insertions(+), 2 deletions(-)
 create mode 100644 src/main/java/me/eigenraven/lwjgl3ify/redirects/JarInputStream.java

diff --git a/src/main/java/me/eigenraven/lwjgl3ify/redirects/JarInputStream.java b/src/main/java/me/eigenraven/lwjgl3ify/redirects/JarInputStream.java
new file mode 100644
index 00000000..41941de2
--- /dev/null
+++ b/src/main/java/me/eigenraven/lwjgl3ify/redirects/JarInputStream.java
@@ -0,0 +1,18 @@
+package me.eigenraven.lwjgl3ify.redirects;
+
+import java.io.EOFException;
+import java.io.IOException;
+import java.util.jar.JarEntry;
+
+public final class JarInputStream {
+
+    public static JarEntry getNextJarEntrySafe(final java.util.jar.JarInputStream jis) throws IOException {
+        try {
+            return jis.getNextJarEntry();
+        } catch (EOFException eof) {
+            System.err.println("EOF caught while searching for forge patches: " + eof);
+            eof.printStackTrace(System.err);
+            return null;
+        }
+    }
+}
diff --git a/src/main/java/me/eigenraven/lwjgl3ify/redirects/Pack200.java b/src/main/java/me/eigenraven/lwjgl3ify/redirects/Pack200.java
index 8c4ddfd4..fec89017 100644
--- a/src/main/java/me/eigenraven/lwjgl3ify/redirects/Pack200.java
+++ b/src/main/java/me/eigenraven/lwjgl3ify/redirects/Pack200.java
@@ -59,11 +59,14 @@ public void unpack(InputStream in, JarOutputStream out) throws IOException {
             // The Apache library doesn't handle LzmaInputStreams well
             final byte[] allData = IOUtils.toByteArray(in);
             parent.unpack(new ByteArrayInputStream(allData), out);
+            out.flush();
+            out.close(); // Forge expects this
         }
 
         @Override
         public void unpack(File in, JarOutputStream out) throws IOException {
             parent.unpack(in, out);
+            out.flush();
         }
 
         @Override
diff --git a/src/main/java/me/eigenraven/lwjgl3ify/rfb/transformers/ForgePatchTransformer.java b/src/main/java/me/eigenraven/lwjgl3ify/rfb/transformers/ForgePatchTransformer.java
index d97793af..ceee779b 100644
--- a/src/main/java/me/eigenraven/lwjgl3ify/rfb/transformers/ForgePatchTransformer.java
+++ b/src/main/java/me/eigenraven/lwjgl3ify/rfb/transformers/ForgePatchTransformer.java
@@ -18,6 +18,7 @@
 import org.objectweb.asm.tree.InsnList;
 import org.objectweb.asm.tree.InsnNode;
 import org.objectweb.asm.tree.LdcInsnNode;
+import org.objectweb.asm.tree.MethodInsnNode;
 import org.objectweb.asm.tree.MethodNode;
 
 import com.gtnewhorizons.retrofuturabootstrap.api.ClassNodeHandle;
@@ -33,12 +34,13 @@ public class ForgePatchTransformer implements RfbClassTransformer {
         return "forge-patch";
     }
 
+    public static final String CLASS_PATCH_MANAGER = "cpw.mods.fml.common.patcher.ClassPatchManager";
     public static final String TRACING_PRINT_STREAM = "cpw.mods.fml.common.TracingPrintStream";
     public static final String FML_SECURITY_MANAGER = "cpw.mods.fml.relauncher.FMLSecurityManager";
     public static final String ENUM_HELPER = "net.minecraftforge.common.util.EnumHelper";
 
-    public static final String[] PATCHED_CLASSES = new String[] { TRACING_PRINT_STREAM, FML_SECURITY_MANAGER,
-        ENUM_HELPER };
+    public static final String[] PATCHED_CLASSES = new String[] { CLASS_PATCH_MANAGER, TRACING_PRINT_STREAM,
+        FML_SECURITY_MANAGER, ENUM_HELPER };
 
     @Override
     public boolean shouldTransformClass(@NotNull ExtensibleClassLoader classLoader,
@@ -59,12 +61,50 @@ public void transformClass(@NotNull ExtensibleClassLoader classLoader, @NotNull
             return;
         }
         switch (className) {
+            case CLASS_PATCH_MANAGER -> tfClassPatchManager(classNode);
             case TRACING_PRINT_STREAM -> tfTracingPrintStream(classNode);
             case FML_SECURITY_MANAGER -> tfFmlSecurityManager(classNode);
             case ENUM_HELPER -> tfEnumHelper(classNode);
         }
     }
 
+    private void tfClassPatchManager(@NotNull ClassNodeHandle handle) {
+        // Fix an infinite loop if an EOFException happens
+        final ClassNode node = handle.getNode();
+        if (node == null || node.methods == null) {
+            logger.error("Class patch manager missing class data");
+            return;
+        }
+        for (final MethodNode mn : node.methods) {
+            if (!"setup".equals(mn.name)) {
+                continue;
+            }
+            if (mn.instructions == null || mn.instructions.size() == 0) {
+                logger.error("ClassPatchManager#setup(Side) missing code");
+                return;
+            }
+            for (final AbstractInsnNode insn : mn.instructions) {
+                if (insn.getOpcode() != INVOKEVIRTUAL) {
+                    continue;
+                }
+                if (!(insn instanceof MethodInsnNode minsn)) {
+                    continue;
+                }
+                if (!"java/util/jar/JarInputStream".equals(minsn.owner)) {
+                    continue;
+                }
+                if (!"getNextJarEntry".equals(minsn.name)) {
+                    continue;
+                }
+                // redirect
+                minsn.setOpcode(INVOKESTATIC);
+                minsn.owner = "me/eigenraven/lwjgl3ify/redirects/JarInputStream";
+                minsn.name = "getNextJarEntrySafe";
+                minsn.desc = "(Ljava/util/jar/JarInputStream;)Ljava/util/jar/JarEntry;";
+            }
+        }
+    }
+
     private void tfTracingPrintStream(@NotNull ClassNodeHandle handle) {
         // Add a close() override that does not close the underlying stream
         // Pack200 tries to close this stream when loading patches.