swaitsandClaude Opus 4.6
a5e3e5f63b
Benchmarking & comparison: - Add criterion benchmarks (ucobs vs cobs 0.3 vs corncobs 0.1) - Add Python cobs benchmark script - Add performance comparison section to README with full results Performance: - Rewrite encode to scan-and-bulk-copy via copy_from_slice - Rewrite decode to bulk-copy via copy_from_slice - ~2-4x throughput improvement; now matches corncobs on most workloads Quality hardening: - Add #![forbid(unsafe_code)], #![warn(missing_docs)], #[must_use] - Add [lints.rust] unsafe_code = "forbid" in Cargo.toml - Add rust-version (MSRV) = "1.56" - Add docs.rs metadata - 106 tests: 80 unit/corpus + 25 property tests (25k cases each = 625k total) - External test vectors from: Wikipedia, Cheshire & Baker paper, nanocobs, cobs-c, cobs2-rs, Jacques Fortier, Python cobs package - Add fuzz_small_dest fuzz target (encode/decode with undersized buffers) - Improve doc examples to show sentinel append/strip convention Infrastructure: - Add justfile with test (nextest), check, bench, fuzz, miri, fmt targets - cargo-nextest for parallel test execution - Update .gitignore for Python cache files Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2.0 KiB
2.0 KiB
μCOBS (ucobs)
Identity
- Crate name:
ucobs(on crates.io) - Display name: μCOBS
- Mission: Become THE COBS crate for Rust — embedded and non-embedded alike
First Principles
- Correct — 100% COBS spec-compliant (Cheshire & Baker 1999). No shortcuts, no deviations.
- Interoperable — proven byte-for-byte compatibility with
corncobs,cobscrates and Pythoncobspackages. - Insanely tested — canonical vectors, property-based tests (proptest), fuzz targets (cargo-fuzz), cross-crate interop, randomized payloads. If you think testing is done, you're 10% done.
- Fast — benchmark against every competing implementation. Must be at least as fast, ideally fastest. Benchmarks are CI-enforced.
- Tiny —
no_std, zero-alloc, zero runtime dependencies. ~120 lines of implementation. Runs on 8-bit MCUs and servers alike. - Trustworthy — small enough to audit by hand. No unsafe. No panics in release. Fuzz-hardened.
Architecture
Single-file library: src/lib.rs
Public API (3 functions)
pub fn encode(src: &[u8], dest: &mut [u8]) -> Option<usize>
pub fn decode(src: &[u8], dest: &mut [u8]) -> Option<usize>
pub const fn max_encoded_len(src_len: usize) -> usize
Convention: Output does NOT include trailing 0x00 sentinel. Caller appends it for framing.
Development
# Run all tests
cargo test
# Fuzz (requires nightly + cargo-fuzz)
cd fuzz
cargo +nightly fuzz run fuzz_decode -- -max_total_time=60
cargo +nightly fuzz run fuzz_roundtrip -- -max_total_time=60
Dev Dependencies (test-only)
corncobs— cross-validation against another COBS implementationproptest— property-based testingrand— randomized test payloads
Roadmap
- More interop targets:
cobscrate, Pythoncobspackage - Benchmarks (criterion) vs corncobs, cobs, and others
- quickcheck in addition to proptest
- Even more fuzz targets and edge-case generators
- MSRV policy and CI
#[deny(unsafe_code)]badge