#include "internal.h"
static const unsigned int prime_1 = 73;
static const unsigned int prime_2 = 5009;
hashset_t hashset_create()
{
hashset_t set = calloc(1, sizeof(struct hashset_st));
if (set == NULL) {
return NULL;
}
set->nbits = 3;
set->capacity = (lcb_size_t)(1 << set->nbits);
set->mask = set->capacity - 1;
set->items = calloc(set->capacity, sizeof(lcb_size_t));
if (set->items == NULL) {
hashset_destroy(set);
return NULL;
}
set->nitems = 0;
return set;
}
lcb_size_t hashset_num_items(hashset_t set)
{
return set->nitems;
}
void hashset_destroy(hashset_t set)
{
if (set) {
free(set->items);
}
free(set);
}
static int hashset_add_member(hashset_t set, void *item)
{
lcb_size_t value = (lcb_size_t)item;
lcb_size_t ii;
if (value == 0 || value == 1) {
return -1;
}
ii = set->mask & (prime_1 * value);
while (set->items[ii] != 0 && set->items[ii] != 1) {
if (set->items[ii] == value) {
return 0;
} else {
ii = set->mask & (ii + prime_2);
}
}
set->nitems++;
set->items[ii] = value;
return 1;
}
static void maybe_rehash(hashset_t set)
{
lcb_size_t *old_items;
lcb_size_t old_capacity, ii;
if ((float)set->nitems >= (lcb_size_t)((double)set->capacity * 0.85)) {
old_items = set->items;
old_capacity = set->capacity;
set->nbits++;
set->capacity = (lcb_size_t)(1 << set->nbits);
set->mask = set->capacity - 1;
set->items = calloc(set->capacity, sizeof(lcb_size_t));
set->nitems = 0;
lcb_assert(set->items);
for (ii = 0; ii < old_capacity; ii++) {
hashset_add_member(set, (void *)old_items[ii]);
}
free(old_items);
}
}
int hashset_add(hashset_t set, void *item)
{
int rv = hashset_add_member(set, item);
maybe_rehash(set);
return rv;
}
int hashset_remove(hashset_t set, void *item)
{
lcb_size_t value = (lcb_size_t)item;
lcb_size_t ii = set->mask & (prime_1 * value);
while (set->items[ii] != 0) {
if (set->items[ii] == value) {
set->items[ii] = 1;
set->nitems--;
return 1;
} else {
ii = set->mask & (ii + prime_2);
}
}
return 0;
}
int hashset_is_member(hashset_t set, void *item)
{
lcb_size_t value = (lcb_size_t)item;
lcb_size_t ii = set->mask & (prime_1 * value);
while (set->items[ii] != 0) {
if (set->items[ii] == value) {
return 1;
} else {
ii = set->mask & (ii + prime_2);
}
}
return 0;
}
void **hashset_get_items(hashset_t set, void **itemlist)
{
lcb_size_t ii, oix;
if (!set->nitems) {
return NULL;
}
if (!itemlist) {
itemlist = malloc(set->nitems * sizeof(void *));
if (!itemlist) {
return NULL;
}
}
for (ii = 0, oix = 0; ii < set->capacity; ii++) {
if (set->items[ii] > 1) {
itemlist[oix] = (void *)set->items[ii];
oix++;
}
}
return itemlist;
}