/* the famous DJB Hash Function for strings */
unsigned int DJBHash(char *str)
{
	unsigned int hash = 5381;
 
	while (*str){
		hash = ((hash << 5) + hash) + (*str++); /* times 33 */
	}
	hash &= ~(1 << 31); /* strip the highest bit */
	return hash;
}

for more information: String hash functions compare