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@jroyalty
Created January 19, 2016 20:36
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Netmask for IPv4 source
#include <stdio.h>
#include <stdlib.h>
#include <maxminddb.h>
int main(int argc, const char * argv[]) {
MMDB_s *mmdb = (MMDB_s *)malloc(sizeof(MMDB_s));
MMDB_open("/tmp/GeoIP2-City_20160105/GeoIP2-City.mmdb",
MMDB_MODE_MMAP, mmdb);
int gai_error = 0;
int mmdb_error = MMDB_SUCCESS;
MMDB_lookup_result_s res = MMDB_lookup_string(mmdb, "71.183.42.223", &gai_error, &mmdb_error);
// Result from legacy database is: 71.183.42.223 = 24
// The following returns: Netmask as returned: 120, corrected: 24
printf("Netmask as returned: %d, corrected: %d\n", res.netmask, res.netmask - mmdb->ipv4_start_node.netmask);
return 0;
}
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