FNV-1a hash function

fnv1a_hash.py

# Fowler–Noll–Vo hash function
# https://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function

fnv_prime_32 = 2**24 + 2**8 + 0x93
offset_basis_32 = 0x811c9dc5

def fnv1a_hash_32(bs):
    r = offset_basis_32
    for b in bs:
        r = r ^ b
        r = (r * fnv_prime_32) & 0xffffffff
    return r

fnv_prime_64 = 2**40 + 2**8 + 0xb3 
offset_basis_64 = 0xcbf29ce484222325

def fnv1a_hash_64(bs):
    r = offset_basis_64
    for b in bs:
        r = r ^ b
        r = (r * fnv_prime_64) & 0xffffffffffffffff
    return r

if __name__ == '__main__':
    test_data = [
        b'hello, world!',
        b'hello, world?',
        b'The Queen is dead',
        b'God save the King',
    ]
    for datum in test_data:
        print(hex(fnv1a_hash_32(datum)), datum.decode('ascii'))
    for datum in test_data:
        print(hex(fnv1a_hash_64(datum)), datum.decode('ascii'))