Paper/Spigot-API-Patches/0193-Make-JavaPluginLoader-thread-safe.patch
Mariell Hoversholm 74f507f4e3 Updated Upstream (Bukkit/CraftBukkit)
Upstream has released updates that appears to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

Bukkit Changes:
e461dcfe #555: Item - add getters/setters for owner/thrower

CraftBukkit Changes:
055870c4 #758: Item - add getters/setters for owner/thrower
2020-10-14 10:44:15 -04:00

60 lines
2.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Trigary <trigary0@gmail.com>
Date: Wed, 15 Apr 2020 01:24:55 -0400
Subject: [PATCH] Make JavaPluginLoader thread-safe
diff --git a/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java b/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java
index de44d850d7b3ab3e528eb6f2de375a6c3e0e5cf9..9d1f7cdf12029c8198792fd299f92be476040222 100644
--- a/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java
+++ b/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java
@@ -52,6 +52,8 @@ public final class JavaPluginLoader implements PluginLoader {
final Server server;
private final Pattern[] fileFilters = new Pattern[]{Pattern.compile("\\.jar$")};
private final Map<String, Class<?>> classes = new ConcurrentHashMap<String, Class<?>>();
+ private final Map<String, java.util.concurrent.locks.ReentrantReadWriteLock> classLoadLock = new java.util.HashMap<String, java.util.concurrent.locks.ReentrantReadWriteLock>(); // Paper
+ private final Map<String, Integer> classLoadLockCount = new java.util.HashMap<String, Integer>(); // Paper
private final List<PluginClassLoader> loaders = new CopyOnWriteArrayList<PluginClassLoader>();
/**
@@ -191,7 +193,19 @@ public final class JavaPluginLoader implements PluginLoader {
@Nullable
Class<?> getClassByName(final String name) {
+ // Paper start - make MT safe
Class<?> cachedClass = classes.get(name);
+ if (cachedClass != null) {
+ return cachedClass;
+ }
+ java.util.concurrent.locks.ReentrantReadWriteLock lock;
+ synchronized (classLoadLock) {
+ lock = classLoadLock.computeIfAbsent(name, (x) -> new java.util.concurrent.locks.ReentrantReadWriteLock());
+ classLoadLockCount.compute(name, (x, prev) -> prev != null ? prev + 1 : 1);
+ }
+ lock.writeLock().lock();try {
+ cachedClass = classes.get(name);
+ // Paper end
if (cachedClass != null) {
return cachedClass;
@@ -205,6 +219,19 @@ public final class JavaPluginLoader implements PluginLoader {
}
}
}
+ // Paper start - make MT safe
+ } finally {
+ synchronized (classLoadLock) {
+ lock.writeLock().unlock();
+ if (classLoadLockCount.get(name) == 1) {
+ classLoadLock.remove(name);
+ classLoadLockCount.remove(name);
+ } else {
+ classLoadLockCount.compute(name, (x, prev) -> prev - 1);
+ }
+ }
+ }
+ // Paper end
return null;
}