Jenkins

Jenkins hash function

The Jenkins hash functions are a collection of (non-cryptographic) hash functions for multi-byte. They can be used also as checksums to detect accidental data corruption or detect identical records in a database.

Informations

• First published - 1997
• Digest sizes - 32 or 64 bits
• Structure - xor/addition

Authors

Bob Jenkins

Implementations

• jenkins.c
• jenkinstest.c

Materials

• Dr. Dobbs article

Pseudocode

uint32_t jenkins_one_at_a_time_hash(char *key, size_t len)
{
    uint32_t hash, i;
    for(hash = i = 0; i < len; ++i)
    {
        hash += key[i];
        hash += (hash << 10);
        hash ^= (hash >> 6);
    }
    hash += (hash << 3);
    hash ^= (hash >> 11);
    hash += (hash << 15);
    return hash;
}