#include <stdio.h>
#include <string.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netdb.h>

int main(int argc, char *argv[])
{
        struct addrinfo *tmp;
        struct addrinfo hints = { 0 };

        memset(&hints, 0, sizeof hints);
        hints.ai_family = AF_INET6;
        hints.ai_flags = AI_NUMERICHOST;
        getaddrinfo("ff01::fb", NULL, &hints, &tmp);

        int m_socket = socket(AF_INET6, SOCK_DGRAM, 0);
        int off = 0;

        if (setsockopt(m_socket, IPPROTO_IPV6, IPV6_V6ONLY, &off, sizeof(off)) < 0) {
                perror("setsockopt");
                return -1;
        }

        struct sockaddr_in6 *in6 = (struct sockaddr_in6*)tmp->ai_addr;
        struct in6_addr* addr6 = &in6->sin6_addr;
        struct ipv6_mreq mreq6 = { 0 };
        memcpy(&mreq6.ipv6mr_multiaddr, addr6, sizeof *addr6);
        mreq6.ipv6mr_interface = 0;

        if (setsockopt(m_socket, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
                perror("setsockopt(IPV6_ADD_MEMBERSHIP)");
                return -1;
        }

        struct sockaddr_in6 addr;
        memset(&addr, 0, sizeof addr);
        memcpy(&addr.sin6_addr, &in6addr_any, sizeof addr);
        addr.sin6_family = AF_INET6;
        addr.sin6_port = htons(5353);
        if (bind(m_socket, (struct sockaddr *)&addr, sizeof addr) < 0) {
                perror("bind");
                return -1;
        }

        memset(&hints, 0, sizeof hints);
        hints.ai_family = AF_INET;
        hints.ai_flags = AI_NUMERICHOST;
        getaddrinfo("224.0.0.251", NULL, &hints, &tmp);
        struct sockaddr_in *in4 = (struct sockaddr_in*)tmp->ai_addr;
        struct in_addr addr4 = in4->sin_addr;
        struct ip_mreqn mreq4 = { 0 };
        memcpy(&mreq4.imr_multiaddr, &addr4, sizeof addr4);
        mreq4.imr_ifindex = 0;

        if (setsockopt(m_socket, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq4, sizeof(mreq4)) < 0) {
                perror("setsockopt(IP_ADD_MEMBERSHIP)");
                return -1;
        }

        while (1) {
                uint8_t buf[2048];
                struct sockaddr_storage saddr;
                socklen_t len = sizeof saddr;

                ssize_t r;
                if ((r = recvfrom(m_socket, buf, sizeof buf, 0, (struct sockaddr *)&saddr, &len)) > 0) {
                        printf("received %ld %u %u\n", r, saddr.ss_family, len);
                } else {
                        perror("recvfrom");
                }
        }

        return 0;
}