Rewrite chunk system (#8177)

Patch documentation to come

Issues with the old system that are fixed now:
- World generation does not scale with cpu cores effectively.
- Relies on the main thread for scheduling and maintaining chunk state, dropping chunk load/generate rates at lower tps.
- Unreliable prioritisation of chunk gen/load calls that block the main thread.
- Shutdown logic is utterly unreliable, as it has to wait for all chunks to unload - is it guaranteed that the chunk system is in a state on shutdown that it can reliably do this? Watchdog shutdown also typically failed due to thread checks, which is now resolved.
- Saving of data is not unified (i.e can save chunk data without saving entity data, poses problems for desync if shutdown is really abnormal.
- Entities are not loaded with chunks. This caused quite a bit of headache for Chunk#getEntities API, but now the new chunk system loads entities with chunks so that they are ready whenever the chunk loads in. Effectively brings the behavior back to 1.16 era, but still storing entities in their own separate regionfiles.

The above list is not complete. The patch documentation will complete it.

New chunk system hard relies on starlight and dataconverter, and most importantly the new concurrent utilities in ConcurrentUtil.

Some of the old async chunk i/o interface (i.e the old file io thread reroutes _some_ calls to the new file io thread) is kept for plugin compat reasons. It will be removed in the next major version of minecraft.

The old legacy chunk system patches have been moved to the removed folder in case we need them again.

1 files changed, 79 insertions, 0 deletions

diff --git a/patches/server/0705-Vanilla-command-permission-fixes.patch b/patches/server/0705-Vanilla-command-permission-fixes.patch
new file mode 100644
index 0000000000..603bc9d5f0
--- /dev/null
+++ b/patches/server/0705-Vanilla-command-permission-fixes.patch
@@ -0,0 +1,79 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Jason Penilla <[email protected]>
+Date: Wed, 25 Aug 2021 13:19:53 -0700
+Subject: [PATCH] Vanilla command permission fixes
+
+Fixes permission checks for vanilla commands which don't have a
+requirement, as well as for namespaced vanilla commands.
+
+diff --git a/src/main/java/com/mojang/brigadier/builder/ArgumentBuilder.java b/src/main/java/com/mojang/brigadier/builder/ArgumentBuilder.java
+index 899008b2980d13f1be6280cd8cb959c53a29bebf..f875507241ac6769545e91cd3285232b75b892f0 100644
+--- a/src/main/java/com/mojang/brigadier/builder/ArgumentBuilder.java
++++ b/src/main/java/com/mojang/brigadier/builder/ArgumentBuilder.java
+@@ -14,9 +14,17 @@ import java.util.Collections;
+ import java.util.function.Predicate;
+ 
+ public abstract class ArgumentBuilder<S, T extends ArgumentBuilder<S, T>> {
++    // Paper start
++    private static final Predicate<Object> DEFAULT_REQUIREMENT = s -> true;
++
++    @SuppressWarnings("unchecked")
++    public static <S> Predicate<S> defaultRequirement() {
++        return (Predicate<S>) DEFAULT_REQUIREMENT;
++    }
++    // Paper end
+     private final RootCommandNode<S> arguments = new RootCommandNode<>();
+     private Command<S> command;
+-    private Predicate<S> requirement = s -> true;
++    private Predicate<S> requirement = defaultRequirement(); // Paper
+     private CommandNode<S> target;
+     private RedirectModifier<S> modifier = null;
+     private boolean forks;
+diff --git a/src/main/java/net/minecraft/commands/Commands.java b/src/main/java/net/minecraft/commands/Commands.java
+index 9c0b2679964f864671ff4041163d1065c8d9cf84..27093aed1f4112a5414671fd5d9c4e683011506d 100644
+--- a/src/main/java/net/minecraft/commands/Commands.java
++++ b/src/main/java/net/minecraft/commands/Commands.java
+@@ -212,7 +212,13 @@ public class Commands {
+         if (environment.includeIntegrated) {
+             PublishCommand.register(this.dispatcher);
+         }
+-
++        // Paper start
++        for (final CommandNode<CommandSourceStack> node : this.dispatcher.getRoot().getChildren()) {
++            if (node.getRequirement() == com.mojang.brigadier.builder.ArgumentBuilder.<CommandSourceStack>defaultRequirement()) {
++                node.requirement = stack -> stack.source == CommandSource.NULL || stack.getBukkitSender().hasPermission(org.bukkit.craftbukkit.command.VanillaCommandWrapper.getPermission(node));
++            }
++        }
++        // Paper end
+         // CraftBukkit start
+     }
+ 
+diff --git a/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java b/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java
+index 5ed34b60a32a2aac214de84c44689fd5a0b00a10..8dca2ad7d25f740941187698d77819af8ebc2805 100644
+--- a/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java
++++ b/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java
+@@ -87,7 +87,23 @@ public final class VanillaCommandWrapper extends BukkitCommand {
+     }
+ 
+     public static String getPermission(CommandNode<CommandSourceStack> vanillaCommand) {
+-        return "minecraft.command." + ((vanillaCommand.getRedirect() == null) ? vanillaCommand.getName() : vanillaCommand.getRedirect().getName());
++        // Paper start
++        final String commandName;
++        if (vanillaCommand.getRedirect() == null) {
++            commandName = vanillaCommand.getName();
++        } else {
++            commandName = vanillaCommand.getRedirect().getName();
++        }
++        return "minecraft.command." + stripDefaultNamespace(commandName);
++    }
++
++    private static String stripDefaultNamespace(final String maybeNamespaced) {
++        final String prefix = "minecraft:";
++        if (maybeNamespaced.startsWith(prefix)) {
++            return maybeNamespaced.substring(prefix.length());
++        }
++        return maybeNamespaced;
++        // Paper end
+     }
+ 
+     private String toDispatcher(String[] args, String name) {