From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Aikar Date: Mon, 6 Jul 2020 18:36:41 -0400 Subject: [PATCH] Fix Concurrency issue in WeightedList if multiple threads from worldgen sort at same time, it will crash. So make a copy of the list for sorting purposes. diff --git a/src/main/java/net/minecraft/world/entity/ai/behavior/BehaviorGate.java b/src/main/java/net/minecraft/world/entity/ai/behavior/BehaviorGate.java index dc926f7e59fa350902d4a24aefc3df3eac7d75db..2d4345de154fb2d31f34695672ebdb4dac31b181 100644 --- a/src/main/java/net/minecraft/world/entity/ai/behavior/BehaviorGate.java +++ b/src/main/java/net/minecraft/world/entity/ai/behavior/BehaviorGate.java @@ -17,7 +17,7 @@ public class BehaviorGate extends Behavior { private final Set> b; private final BehaviorGate.Order c; private final BehaviorGate.Execution d; - private final WeightedList> e = new WeightedList<>(); + private final WeightedList> e = new WeightedList<>(false); // Paper - don't use a clone public BehaviorGate(Map, MemoryStatus> map, Set> set, BehaviorGate.Order behaviorgate_order, BehaviorGate.Execution behaviorgate_execution, List, Integer>> list) { super(map); @@ -65,10 +65,9 @@ public class BehaviorGate extends Behavior { }).forEach((behavior) -> { behavior.g(worldserver, e0, i); }); - Set set = this.b; BehaviorController behaviorcontroller = e0.getBehaviorController(); - set.forEach(behaviorcontroller::removeMemory); + this.b.forEach(behaviorcontroller::removeMemory); // Paper - decomp fix } @Override @@ -115,7 +114,7 @@ public class BehaviorGate extends Behavior { private final Consumer> c; - private Order(Consumer consumer) { + private Order(Consumer> consumer) { // Paper - decomp fix this.c = consumer; } diff --git a/src/main/java/net/minecraft/world/entity/ai/behavior/WeightedList.java b/src/main/java/net/minecraft/world/entity/ai/behavior/WeightedList.java index f6f8c68ff3642e28901094e8b501fcf8ec2cecd7..1ca9b0595ae9d914d23590ec0b0c2e857c39b250 100644 --- a/src/main/java/net/minecraft/world/entity/ai/behavior/WeightedList.java +++ b/src/main/java/net/minecraft/world/entity/ai/behavior/WeightedList.java @@ -6,7 +6,7 @@ import com.mojang.serialization.Codec; import com.mojang.serialization.DataResult; import com.mojang.serialization.Dynamic; import com.mojang.serialization.DynamicOps; -import com.mojang.serialization.OptionalDynamic; + import java.util.Comparator; import java.util.List; import java.util.Random; @@ -14,26 +14,32 @@ import java.util.stream.Stream; public class WeightedList { - protected final List> a; + protected final List> list; // Paper - decompile conflict private final Random b; + private final boolean isUnsafe; // Paper - public WeightedList() { - this(Lists.newArrayList()); + // Paper start - add useClone option + public WeightedList() { this(true); } + public WeightedList(boolean isUnsafe) { + this(Lists.newArrayList(), isUnsafe); } - private WeightedList(List> list) { + private WeightedList(List> list) { this(list, true); } + private WeightedList(List> list, boolean isUnsafe) { + this.isUnsafe = isUnsafe; + // Paper end this.b = new Random(); - this.a = Lists.newArrayList(list); + this.list = Lists.newArrayList(list); // Paper - decompile conflict } public static Codec> a(Codec codec) { - return WeightedList.a.a(codec).listOf().xmap(WeightedList::new, (weightedlist) -> { - return weightedlist.a; + return WeightedList.a.a(codec).listOf().xmap(WeightedList::new, (weightedlist) -> { // Paper - decompile conflict + return weightedlist.list; // Paper - decompile conflict }); } public WeightedList a(U u0, int i) { - this.a.add(new WeightedList.a<>(u0, i)); + this.list.add(new WeightedList.a<>(u0, i)); // Paper - decompile conflict return this; } @@ -42,21 +48,20 @@ public class WeightedList { } public WeightedList a(Random random) { - this.a.forEach((weightedlist_a) -> { - weightedlist_a.a(random.nextFloat()); - }); - this.a.sort(Comparator.comparingDouble((object) -> { - return ((WeightedList.a) object).c(); - })); - return this; + // Paper start - make concurrent safe, work off a clone of the list + List> list = isUnsafe ? new java.util.ArrayList>(this.list) : this.list; + list.forEach((weightedlist_a) -> weightedlist_a.a(random.nextFloat())); + list.sort(Comparator.comparingDouble(a::c)); + return isUnsafe ? new WeightedList<>(list, isUnsafe) : this; + // Paper end } public boolean b() { - return this.a.isEmpty(); + return this.list.isEmpty(); // Paper - decompile conflict } public Stream c() { - return this.a.stream().map(WeightedList.a::a); + return this.list.stream().map(WeightedList.a::a); // Paper - decompile conflict } public U b(Random random) { @@ -64,7 +69,7 @@ public class WeightedList { } public String toString() { - return "WeightedList[" + this.a + "]"; + return "WeightedList[" + this.list + "]"; // Paper - decompile conflict } public static class a { @@ -98,11 +103,7 @@ public class WeightedList { return new Codec>() { public DataResult, T>> decode(DynamicOps dynamicops, T t0) { Dynamic dynamic = new Dynamic(dynamicops, t0); - OptionalDynamic optionaldynamic = dynamic.get("data"); - Codec codec1 = codec; - - codec.getClass(); - return optionaldynamic.flatMap(codec1::parse).map((object) -> { + return dynamic.get("data").flatMap(codec::parse).map((object) -> { // Paper - decompile error return new WeightedList.a<>(object, dynamic.get("weight").asInt(1)); }).map((weightedlist_a) -> { return Pair.of(weightedlist_a, dynamicops.empty());