# Function cargo::sources::registry::max_unpack_size

source ·

    fn max_unpack_size(gctx: &GlobalContext, size: u64) -> u64

Expand description

Get the maximum unpack size that Cargo permits based on a given `size` of your compressed file.

Returns the larger one between `size * max compression ratio` and a fixed max unpacked size.

In reality, the compression ratio usually falls in the range of 2:1 to 10:1. We choose 20:1 to cover almost all possible cases hopefully. Any ratio higher than this is considered as a zip bomb.

In the future we might want to introduce a configurable size.

Some of the real world data from common compression algorithms:

- https://www.zlib.net/zlib_tech.html
- https://cran.r-project.org/web/packages/brotli/vignettes/brotli-2015-09-22.pdf
- https://blog.cloudflare.com/results-experimenting-brotli/
- https://tukaani.org/lzma/benchmarks.html