compress-lib 0.4.0

Scope

Raw DEFLATE inflate and deflate with window bits 8 to 15 and levels 0 to 9; sync, full, and finish flushes; zlib and gzip framing with checksums always verified; preset dictionaries; per-message compression for WebSocket servers and clients (context takeover on or off); CRC-32 and Adler-32; std::io adapters. Brotli follows after 1.0. It does not negotiate HTTP or WebSocket headers (http-net and ws-net do) and it does not read archives.

Quick start

[dependencies]
compress = { package = "compress-lib", version = "0.4" }

Available now:

let packed = compress::deflate::compress(data);        // raw DEFLATE, level 6
let data = compress::deflate::decompress(&packed)?;   // capped at 64 MiB
let crc = compress::checksum::crc32(&data);           // gzip's checksum

WebSocket permessage-deflate (RFC 7692), one direction each:

use compress::message::{Compressor, Decompressor, MessageConfig};

let config = MessageConfig::new().with_window_bits(12);   // no context takeover by default
let mut tx = Compressor::new(config)?;
let mut rx = Decompressor::new(config)?;
tx.compress_message(text, &mut payload)?;               // sync flush, tail removed
rx.decompress_message(&payload, &mut message, max)?;    // budget checked while inflating

Streaming, with buffers you own:

use compress::deflate::{Deflater, Flush, Inflater, Status};

let p = deflater.compress(input, &mut output, Flush::None)?;  // push input, pull output
let q = inflater.decompress(input, &mut output)?;
match q.status {
    Status::NeedsInput => { /* feed input[q.consumed..] and more */ }
    Status::NeedsOutput => { /* drain output[..q.produced], call again */ }
    _ => { /* Status::Done: the stream ended at input[q.consumed] */ }
}

Planned for 0.5, the same shape:

let packed = compress::gzip::compress(body);          // Vec<u8>, level 6
let body = compress::gzip::decompress(&packed)?;      // capped at 64 MiB by default

The complete planned API, with the version each item arrives in, is in docs/API.md.

Contributing

See dev/DIRECTIVES.md for engineering standards and the definition of done. Before a PR: cargo fmt --all, cargo clippy --all-targets --all-features -- -D warnings, and cargo test --all-features must be clean.