| # crc [](https://travis-ci.org/mrhooray/crc-rs) |
| > Rust implementation of CRC(16, 32, 64) with support of various standards |
| |
| * [Crate](https://crates.io/crates/crc) |
| * [Documentation](https://docs.rs/crc/) |
| * [Usage](#usage) |
| * [Benchmark](#benchmark) |
| * [License](#license) |
| |
| ## Usage |
| Add `crc` to `Cargo.toml` |
| ```toml |
| [dependencies] |
| crc = "^1.0.0" |
| ``` |
| or |
| ```toml |
| [dependencies.crc] |
| git = "https://github.com/mrhooray/crc-rs" |
| ``` |
| |
| Add this to crate root |
| ```rust |
| extern crate crc; |
| ``` |
| |
| ### Compute CRC16 |
| ```rust |
| use crc::{crc16, Hasher16}; |
| |
| assert_eq!(crc16::checksum_x25(b"123456789"), 0x906e); |
| assert_eq!(crc16::checksum_usb(b"123456789"), 0xb4c8); |
| |
| // use provided or custom polynomial |
| let mut digest = crc16::Digest::new(crc16::X25); |
| digest.write(b"123456789"); |
| assert_eq!(digest.sum16(), 0x906e); |
| |
| // with initial |
| let mut digest = crc16::Digest::new_with_initial(crc16::X25, 0u16); |
| digest.write(b"123456789"); |
| assert_eq!(digest.sum16(), 0x906e); |
| ``` |
| |
| ### Compute CRC32 |
| ```rust |
| use crc::{crc32, Hasher32}; |
| |
| // CRC-32-IEEE being the most commonly used one |
| assert_eq!(crc32::checksum_ieee(b"123456789"), 0xcbf43926); |
| assert_eq!(crc32::checksum_castagnoli(b"123456789"), 0xe3069283); |
| assert_eq!(crc32::checksum_koopman(b"123456789"), 0x2d3dd0ae); |
| |
| // use provided or custom polynomial |
| let mut digest = crc32::Digest::new(crc32::IEEE); |
| digest.write(b"123456789"); |
| assert_eq!(digest.sum32(), 0xcbf43926); |
| |
| // with initial |
| let mut digest = crc32::Digest::new_with_initial(crc32::IEEE, 0u32); |
| digest.write(b"123456789"); |
| assert_eq!(digest.sum32(), 0xcbf43926); |
| ``` |
| |
| ### Compute CRC64 |
| ```rust |
| use crc::{crc64, Hasher64}; |
| |
| assert_eq!(crc64::checksum_ecma(b"123456789"), 0x995dc9bbdf1939fa); |
| assert_eq!(crc64::checksum_iso(b"123456789"), 0xb90956c775a41001); |
| |
| // use provided or custom polynomial |
| let mut digest = crc64::Digest::new(crc64::ECMA); |
| digest.write(b"123456789"); |
| assert_eq!(digest.sum64(), 0x995dc9bbdf1939fa); |
| |
| // with initial |
| let mut digest = crc64::Digest::new_with_initial(crc64::ECMA, 0u64); |
| digest.write(b"123456789"); |
| assert_eq!(digest.sum64(), 0x995dc9bbdf1939fa); |
| ``` |
| |
| ## Benchmark |
| > Bencher is currently not available in Rust stable releases. |
| |
| `cargo bench` with 2.3 GHz Intel Core i7 results ~430MB/s throughput. [Comparison](http://create.stephan-brumme.com/crc32/) |
| ``` |
| cargo bench |
| Running target/release/bench-5c82e94dab3e9c79 |
| |
| running 4 tests |
| test bench_crc32_make_table ... bench: 439 ns/iter (+/- 82) |
| test bench_crc32_update_megabytes ... bench: 2327803 ns/iter (+/- 138845) |
| test bench_crc64_make_table ... bench: 1200 ns/iter (+/- 223) |
| test bench_crc64_update_megabytes ... bench: 2322472 ns/iter (+/- 92870) |
| |
| test result: ok. 0 passed; 0 failed; 0 ignored; 4 measured |
| ``` |
| |
| ## License |
| |
| Licensed under either of |
| |
| * Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0) |
| * MIT License ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT) |
| |
| at your option. |
| |
| ### Contribution |
| |
| Unless you explicitly state otherwise, any contribution intentionally submitted |
| for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any |
| additional terms or conditions. |
