rustc/vendor/rustc-stable-hash-0.1.1/README.md
2025-02-17 11:14:05 +01:00

33 lines
1.1 KiB
Markdown

# rustc-stable-hash
[![crates.io](https://img.shields.io/crates/v/rustc-stable-hash.svg)](https://crates.io/crates/rustc-stable-hash)
[![Documentation](https://docs.rs/rustc-stable-hash/badge.svg)](https://docs.rs/rustc-stable-hash)
A stable hashing algorithm used by `rustc`: cross-platform, deterministic, not secure.
This crate provides facilities with the `StableHasher` structure to create stable hashers over *unstable* hashers by abstracting over them the handling of endian-ness and the target `usize`/`isize` bit size difference.
Currently, this crate provides it's own implementation of 128-bit `SipHasher`: `SipHasher128`; with `StableSipHasher128` for the stable variant.
## Usage
```rust
use rustc_stable_hash::hashers::{StableSipHasher128, SipHasher128Hash};
use rustc_stable_hash::FromStableHash;
use std::hash::Hasher;
struct Hash128([u64; 2]);
impl FromStableHash for Hash128 {
type Hash = SipHasher128Hash;
fn from(SipHasher128Hash(hash): SipHasher128Hash) -> Hash128 {
Hash128(hash)
}
}
let mut hasher = StableSipHasher128::new();
hasher.write_usize(0xFA);
let hash: Hash128 = hasher.finish();
```