From 03abdfdc498965bb387588162a2c7de7555f74a2 Mon Sep 17 00:00:00 2001
From: embeddedt <42941056+embeddedt@users.noreply.github.com>
Date: Tue, 9 May 2023 16:52:10 -0400
Subject: [PATCH 1/2] Optimize server thread aliveness check

---
 .../mixin/bugfix/chunk_deadlock/ServerChunkCacheMixin.java      | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/common/src/main/java/org/embeddedt/modernfix/common/mixin/bugfix/chunk_deadlock/ServerChunkCacheMixin.java b/common/src/main/java/org/embeddedt/modernfix/common/mixin/bugfix/chunk_deadlock/ServerChunkCacheMixin.java
index 682577bd..baf84759 100644
--- a/common/src/main/java/org/embeddedt/modernfix/common/mixin/bugfix/chunk_deadlock/ServerChunkCacheMixin.java
+++ b/common/src/main/java/org/embeddedt/modernfix/common/mixin/bugfix/chunk_deadlock/ServerChunkCacheMixin.java
@@ -29,7 +29,7 @@ public abstract class ServerChunkCacheMixin {
 
     @Inject(method = "getChunk", at = @At("HEAD"), cancellable = true)
     private void bailIfServerDead(int chunkX, int chunkZ, ChunkStatus requiredStatus, boolean load, CallbackInfoReturnable<ChunkAccess> cir) {
-        if(!this.mainThread.isAlive()) {
+        if(!this.level.getServer().isRunning() && !this.mainThread.isAlive()) {
             ModernFix.LOGGER.fatal("A mod is accessing chunks from a stopped server (this will also cause memory leaks)");
             if(debugDeadServerAccess) {
                 new Exception().printStackTrace();

From bcb33a1018a7c58056d5fc91add49c9838b948e6 Mon Sep 17 00:00:00 2001
From: embeddedt <42941056+embeddedt@users.noreply.github.com>
Date: Wed, 10 May 2023 09:54:14 -0400
Subject: [PATCH 2/2] Shorten structure hashes to fix issues on Windows

---
 .../structure/CachingStructureManager.java    | 22 +++++++++++++------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/common/src/main/java/org/embeddedt/modernfix/structure/CachingStructureManager.java b/common/src/main/java/org/embeddedt/modernfix/structure/CachingStructureManager.java
index b5ed3b88..365fb4d7 100644
--- a/common/src/main/java/org/embeddedt/modernfix/structure/CachingStructureManager.java
+++ b/common/src/main/java/org/embeddedt/modernfix/structure/CachingStructureManager.java
@@ -49,6 +49,12 @@ public class CachingStructureManager {
 
     private static final Set<String> laggyStructureMods = new ObjectOpenHashSet<>();
 
+    private static final int MAX_HASH_LENGTH = 9;
+
+    private static String truncateHash(String hash) {
+        return hash.substring(0, MAX_HASH_LENGTH + 1);
+    }
+
     public static CompoundTag readStructureTag(ResourceLocation location, DataFixer datafixer, InputStream stream) throws IOException {
         byte[] structureBytes = toBytes(stream);
         CompoundTag currentTag = NbtIo.readCompressed(new ByteArrayInputStream(structureBytes));
@@ -57,20 +63,22 @@ public class CachingStructureManager {
         }
         int currentDataVersion = currentTag.getInt("DataVersion");
         if(currentDataVersion < SharedConstants.getCurrentVersion().getWorldVersion()) {
-            synchronized (laggyStructureMods) {
-                if(laggyStructureMods.add(location.getNamespace())) {
-                    ModernFix.LOGGER.warn("Mod {} is shipping outdated structure files, which can cause worldgen lag; please report this to them.", location.getNamespace());
-                }
-            }
             /* Needs upgrade, try looking up from cache */
             MessageDigest hasher = digestThreadLocal.get();
             hasher.reset();
             String hash = encodeHex(hasher.digest(structureBytes));
-            CompoundTag cachedUpgraded = getCachedUpgraded(location, hash);
+            CompoundTag cachedUpgraded = getCachedUpgraded(location, truncateHash(hash));
+            if(cachedUpgraded == null)
+                cachedUpgraded = getCachedUpgraded(location, hash); /* pick up old cache */
             if(cachedUpgraded != null && cachedUpgraded.getInt("DataVersion") == SharedConstants.getCurrentVersion().getWorldVersion()) {
                 ModernFix.LOGGER.debug("Using cached upgraded version of {}", location);
                 currentTag = cachedUpgraded;
             } else {
+                synchronized (laggyStructureMods) {
+                    if(laggyStructureMods.add(location.getNamespace())) {
+                        ModernFix.LOGGER.warn("Mod {} is shipping outdated structure files, which can cause worldgen lag; please report this to them.", location.getNamespace());
+                    }
+                }
                 ModernFix.LOGGER.debug("Structure {} is being run through DFU (hash {}), this will cause launch time delays", location, hash);
                 currentTag = NbtUtils.update(datafixer, DataFixTypes.STRUCTURE, currentTag, currentDataVersion,
                         SharedConstants.getCurrentVersion().getWorldVersion());
@@ -99,7 +107,7 @@ public class CachingStructureManager {
     }
 
     private static synchronized void saveCachedUpgraded(ResourceLocation location, String hash, CompoundTag tagToSave) {
-        File theFile = getCachePath(location, hash);
+        File theFile = getCachePath(location, truncateHash(hash));
         try {
             NbtIo.writeCompressed(tagToSave, theFile);
         } catch(IOException e) {