#include <stdlib.h>

/*
 *
 * 32 bit FNV-1a algorithm
 * https://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function
 *
 */
static size_t hash_key(const char *key, const size_t max_hash_value) {
  uint32_t hash = 2166136261U; /* FNV-1a 32-bit offset basis */
  /*
   * We'll explicitly use unsigned chars here, since we're doing arithmetic. The
   * C standard doesn't state whether an implementation must use signed or
   * unsigned values for characters, so this conversion ensures we get
   * correct behavior. If signed characters are used, we'll get overflows
   * and other odd issues in the hash calculation.
   */
  const unsigned char *p = (unsigned char *) key;

  while (*p) {
    hash ^= *p++;
    hash *= 16777619U; /* FNV-1a prime */
  }

  return hash % max_hash_value;
}

static size_t test_hash(const char *key, const size_t max_hash_value) {
  (void) max_hash_value;

  return key[0] % 3;
}