Crate cityhash_sys

CityHash provides hash functions for strings. CityHash mix the input bits thoroughly but are not suitable for cryptography. It is a Rust binding of Google CityHash library

CityHash-sys do not load the standard library (a.k.a #![no_std])

It provides 32-bits, 64-bits, 128-bits and 256-bits hash. 256-bits hash is available only for x86_64 target_arch with sse4.2. See the README for more informations

Example

use cityhash_sys::{city_hash_128, city_hash_32, city_hash_64};

// Provides free functions
assert_eq!(city_hash_32(&[0,1,2,3,4]), 0xFE6E37D4u32);
assert_eq!(city_hash_64(&[0,1,2,3,4]), 0xB4BFA9E87732C149u64);
assert_eq!(city_hash_128(&[0,1,2,3,4]), 0xE3CB1F3F3AB9643BEF3668C150012EECu128);

// Provides trait implementation for [u8] and str
use cityhash_sys::CityHash;
 
assert_eq!([5u8, 4, 3, 2, 1].city_hash_64(), 0x34EC5F7922A51496);
assert_eq!("hash me!".city_hash_64(), 0xF04A0CC67B63A0B4);

// Some 128-bits and the 256-bits hash needs x86_64 architecture with sse 4.2
// Free functions that need it start with city_hash_crc_...
// Trait that provides the implementation is named with CityHashCrc
#[cfg(all(target_arch = "x86_64", target_feature = "sse4.2"))]
use cityhash_sys::CityHashCrc;

#[cfg(all(target_arch = "x86_64", target_feature = "sse4.2"))]
assert_eq!([0u8,1,2,3,4].city_hash_crc_128(), 0xE3CB1F3F3AB9643BEF3668C150012EECu128);

#[cfg(all(target_arch = "x86_64", target_feature = "sse4.2"))]
assert_eq!([0u8,1,2,3,4].city_hash_crc_256(), [0xA7FAC4B64C35C8B4,0xDD83C2CDF35398F6,0xEAF64F6BA6A2C9E8,0x4E72CE1685CE9077]);

Traits

CityHash

CityHash trait provides CityHash functions to type that implement this trait. This trait is a syntax sugar for city_hash_... functions.

CityHashCrc

CityHashCrc trait provides CityHash functions to type that implement this trait. CityHashCrc need the CRC32 intrinsics that is only available for x86_64 target_arch with sse4.2. This trait is a syntax sugar for city_hash_crc_... functions.

Functions

city_hash_32

Retrieves a 32-bit hash of a slice of bytes.

city_hash_64

Retrieves a 64-bit hash of a slice of bytes.

city_hash_64_with_seed

Retrieves a 64-bit hash of a slice of bytes, a seed is also hashed into the result.

city_hash_64_with_seeds

Retrieves a 64-bit hash of a slice of bytes, two seeds is also hashed into the result.

city_hash_128

Retrieves a 128-bit hash of a slice of bytes.

city_hash_128_to_64

Retrieves the 64 bits of a 128 bits input.

city_hash_128_with_seed

Retrieves a 128-bit hash of a slice of bytes, a seed is also hashed into the result.

city_hash_crc_128

Retrieves a 128-bit hash of a slice of bytes.

city_hash_crc_128_with_seed

Retrieves a 128-bit hash of a slice of bytes, a seed is also hashed into the result.

city_hash_crc_256

Retrieves a 256-bit hash fo a slice of bytes. The hash is a slice of u64 where [0..4] is [low..high] bits.