47 lines
1.2 KiB
C
47 lines
1.2 KiB
C
#include "bloom.h"
|
|
#include "ens/storage.h"
|
|
#include "exposure-notification.h"
|
|
|
|
bloom_filter_t* bloom_init(size_t size) {
|
|
bloom_filter_t* bloom = k_calloc(1, sizeof(bloom_filter_t));
|
|
if (!bloom) {
|
|
return NULL;
|
|
}
|
|
bloom->size = size;
|
|
bloom->data = k_calloc(size, sizeof(uint8_t));
|
|
if (!bloom->data) {
|
|
bloom->size = 0;
|
|
k_free(bloom);
|
|
return NULL;
|
|
}
|
|
return bloom;
|
|
}
|
|
|
|
void bloom_destroy(bloom_filter_t* bloom) {
|
|
if (bloom) {
|
|
k_free(bloom->data);
|
|
k_free(bloom);
|
|
}
|
|
}
|
|
|
|
void bloom_add_record(bloom_filter_t* bloom, ENIntervalIdentifier* rpi) {
|
|
uint8_t* data = bloom->data;
|
|
for (int i = 0; i < sizeof(*rpi); i += 2) {
|
|
uint32_t hash = (rpi->b[i] << 8) | rpi->b[i + 1];
|
|
hash %= bloom->size * 8;
|
|
data[hash / 8] |= 1 << (hash % 8);
|
|
}
|
|
}
|
|
|
|
bool bloom_probably_has_record(bloom_filter_t* bloom, ENIntervalIdentifier* rpi) {
|
|
uint8_t* data = bloom->data;
|
|
for (int i = 0; i < sizeof(*rpi); i += 2) {
|
|
uint32_t hash = (rpi->b[i] << 8) | rpi->b[i + 1];
|
|
hash %= bloom->size * 8;
|
|
if (!(data[hash / 8] & (1 << (hash % 8)))) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|