If a chunk load comes in on a chunk load or gen thread,
execute it synchronously on that thread instead of enqueueing it.
It doesn't make sense to enqueue it as that thread is then
going to future.join() it and block until it's ready anyways.
This opens risk to a deadlock if every load or gen thread is
waiting on a recursive chunk but it will never finish because
all of the threads are waiting.
If we identify an invalid offset (negative, or the header sectors),
then back up the region file and erase that specific chunks offset
data.
This will avoid crashing the server with AIOBB errors and also avoids
server owners having to consider the entire region file 'lost'.
I'm not sure what leads to this state, I can only assume write cut
off mid bits.
In this scenario, there is absolutely no way to know where the chunk
actually is in the data file without loading every
single chunk in the file. And even to do that, would be quite extreme
due to the fact the file isn't in some orderly fashion.
Since the file is backed up, the user can use a region fixer tool
externally to try to restore that single chunk. We could even
add a command to restore a chunk from a backup file in a different
commit later on. But this at least prevents the server from crashing.
The server will just generate a new chunk and move on,
after printing an error to the console about it.
Also fixed the case reported in this issue about the server
hanging when a corrupt chunk is encountered, so this issue
is now fully closed.
Resolves#1541
ForgeFlower is better than Spigots FernFlower at decompiling the source.
However, in order to maintain the CraftBukkit patches, we must keep
using spigots for the primary.
However, for any file that we import on top of Spigots imported files
there is nothing stopping us from using better decompiled files.
So these changes will use ForgeFlower to maintain a better set of
decomped files, so anything we add on top of Paper can start off
in a better spot.
Updated Upstream (Bukkit/CraftBukkit/Spigot)
Bukkit Changes:
2dcc44dc SPIGOT-4307: Fix hacky API for banners on shields
e0fc6572 SPIGOT-4309: Add "forced" display of particles
efeeab2f Add index to README.md for easier navigation
f502bc6f Update to Minecraft 1.13.1
CraftBukkit Changes:
d0bb0a1d Fix some tests randomly failing
997d378d Fix client stall in specific teleportation scenarios
b3dc2366 SPIGOT-4307: Fix hacky API for banners on shields
2a271162 SPIGOT-4301: Fix more invalid enchants
5d0d83bb SPIGOT-4309: Add "forced" display of particles
a6772578 Add additional tests for CraftBlockData
ce1af0c3 Update to Minecraft 1.13.1
Spigot Changes:
2440e189 Rebuild patches
4ecffced Update to Minecraft 1.13.1
If the file has partial data written but not the full 8192 bytes,
then the server will be unable to load that region file...
I don't know why mojang only checks for 4096, when anything less than 8192 is a crash.
But to be safe, it will attempt to back up the file.