diff --git a/examples/mcpe/src/main.rs b/examples/mcpe/src/main.rs index 65360cd..e0a6f13 100644 --- a/examples/mcpe/src/main.rs +++ b/examples/mcpe/src/main.rs @@ -1,8 +1,10 @@ use miniz_oxide::deflate::{compress_to_vec, compress_to_vec_zlib}; use miniz_oxide::inflate::{decompress_to_vec, decompress_to_vec_zlib}; +use rusty_leveldb::compressor::NoneCompressor; use rusty_leveldb::{Compressor, CompressorList, Options, DB}; use std::rc::Rc; +/// A zlib compressor that with zlib wrapper struct ZlibCompressor(u8); impl ZlibCompressor { @@ -26,6 +28,15 @@ impl Compressor for ZlibCompressor { } } +/// A zlib compressor that without zlib wrapper +/// +/// > windowBits can also be –8..–15 for raw deflate. In this case, -windowBits determines the window size. deflate() will then generate raw deflate data with no zlib header or trailer, and will not compute a check value. +/// > +/// > From [zlib manual](https://zlib.net/manual.html) +/// +/// It seems like mojang use this most +/// +/// A copy of mojang's implementation can be find [here](https://github.com/reedacartwright/rbedrock/blob/fb32a899da4e15c1aaa0d6de2b459e914e183516/src/leveldb-mcpe/db/zlib_compressor.cc#L119). struct RawZlibCompressor(u8); impl RawZlibCompressor { @@ -51,18 +62,30 @@ impl Compressor for RawZlibCompressor { pub fn mcpe_options(compression_level: u8) -> Options { let mut opt = Options::default(); - opt.compressor = 0; + + // compressor id list can be find in [mojang's implementation](https://github.com/reedacartwright/rbedrock/blob/fb32a899da4e15c1aaa0d6de2b459e914e183516/src/leveldb-mcpe/include/leveldb/c.h#L194-L200) + // And it seems like mojang don't use slippy or zstd of minecraft bedrock + // + // If you need to open old world, old world fallback compressor can be find [here](https://github.com/reedacartwright/rbedrock/blob/fb32a899da4e15c1aaa0d6de2b459e914e183516/src/bedrock_leveldb.c#L152-L153) let mut list = CompressorList::new(); - list.set_with_id(0, RawZlibCompressor::new(compression_level)); - list.set_with_id(1, ZlibCompressor::new(compression_level)); + list.set_with_id(0, NoneCompressor::default()); + list.set_with_id(2, ZlibCompressor::new(compression_level)); + list.set_with_id(4, RawZlibCompressor::new(compression_level)); opt.compressor_list = Rc::new(list); + + // Set compressor + // Minecraft bedrock may use other id than 4 + // + // There is a bug in this library that you have to open a database with the same compression type as it was written to. + opt.compressor = 4; + opt } fn main() { let path = "mcpe_db"; - let compression_level = 10; - let opt = mcpe_options(compression_level); + const COMPRESSION_LEVEL: u8 = 10; + let opt = mcpe_options(COMPRESSION_LEVEL); let mut db = DB::open(path, opt).unwrap(); db.put(b"~local_player", b"NBT data goes here").unwrap(); let value = db.get(b"~local_player").unwrap();