# refpack-rs
[](https://github.com/actioninja/refpack-rs/actions/workflows/check-and-test.yml)
[](https://github.com/actioninja/refpack-rs/blob/master/LICENSE.md)
[](https://coveralls.io/github/actioninja/refpack-rs?branch=master)
A rust crate for compressing and decompressing data in the RefPack format utilized by
many EA games of the early 2000s
More details on the refpack format can be found at [the niotso wiki](http://wiki.niotso.org/RefPack). The short explanation is that RefPack is a compression scheme loosely based on LZ77 compression.
The [Original Refpack Implementation](http://download.wcnews.com/files/documents/sourcecode/shadowforce/transfer/asommers/mfcapp_src/engine/compress/RefPack.cpp)
was referenced to ensure proper compatibility
## NOT SC4 COMPATIBLE
SimCity 4 uses a different bit layout for its compression. I may eventually add a feature flag for "sc4 mode" but there isn't really a programmatic way to identify it and I would prefer not to complicate the API.
# Usage
`refpack-rs` exposes two functions: `compress` and `decompress`, along with `easy` variants
with easier but less flexible of usage.
`compress` and `decompress` take mutable references to a buffer to read and write from,
that implements `std::io::Read` and `std::io::Write`, respectively.
`decompress` will read from the buffer until it encounters a stopcode (byte within (0xFC..=0xFF)),
while `compress` will read in the provided length.
### Example
```rust
let mut out_buf = Cursor::new(vec![]);
decompress(&mut source_reader, &mut out_buf)?;
```
The easy variants are `compress_easy` and `decompress_easy`, which take a `&[u8]` and return
a `Result<Vec<u8>, RefPackError>`.
Internally they simply call `compress` and `decompress` with a `Cursor` to the input and
output buffers, however they are more convenient to use in many cases.