C++ address::is_multicast方法代码示例

int SetupSocket(const address &addr, bool shouldbind, bool ssm) {
	int af_family = addr.family();
	int level = addr.optlevel();

	int sock = socket(af_family, SOCK_DGRAM, 0);
	if (sock < 0) {
		perror("Failed to create multicast socket");
		return -1;
	}

	int on = 1;

	if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) != 0) {
		perror("setsockopt");
		return -1;
	}

	if (shouldbind) {
		if (bind(sock, addr.saddr(), addr.addrlen()) != 0) {
			perror("Failed to bind multicast socket");
			return -1;
		}
	}

#ifdef SO_TIMESTAMP
	if (setsockopt(sock, SOL_SOCKET, SO_TIMESTAMP, &on, sizeof(on)) != 0) {
		perror("setsockopt(SO_TIMESTAMP)");
		return -1;
	}
#endif

	int type = level == IPPROTO_IPV6 ?
#ifdef IPV6_RECVHOPLIMIT
				IPV6_RECVHOPLIMIT
#else
				IPV6_HOPLIMIT
#endif
				:
#ifdef IP_RECVTTL
				IP_RECVTTL;
#else
				IP_TTL;
#endif

	if (setsockopt(sock, level, type, &on, sizeof(on)) != 0) {
		perror("receiving hop limit/ttl setsockopt()");
		return -1;
	}

	if (!SetHops(sock, addr, defaultTTL)) {
		perror("SetHops");
		return -1;
	}

	if (!ssm && addr.is_multicast()) {
		if (MulticastListen(sock, addr) != 0) {
			perror("Failed to join multicast group");
			return -1;
		}
	}

	return sock;
}

int main(int argc, char **argv) {
	int res;

	srand(time(NULL));

	char tmp[256];
	if (gethostname(tmp, sizeof(tmp)) != 0) {
		perror("Failed to get hostname");
		return -1;
	}

	beaconName = tmp;

	parse_arguments(argc, argv);

	MulticastStartup();

	if (beaconName.empty())
		fatal("No name supplied, check `dbeacon -h`.");

	if (!probeAddrLiteral.empty()) {
		if (!probeAddr.parse(probeAddrLiteral.c_str(), true))
			return -1;

		probeAddr.to_string(sessionName, sizeof(sessionName));

		if (!probeAddr.is_multicast())
			fatal("Specified probe addr (%s) is not of a multicast group.",
					sessionName);

		if (adminContact.empty())
			fatal("No administration contact supplied, check `dbeacon -h`.");

		mcastListen.push_back(ContentDesc(probeAddr, false));

		insert_event(SENDING_EVENT, 100);
		insert_event(REPORT_EVENT, 10000);
		insert_event(MAP_REPORT_EVENT, 30000);
		insert_event(WEBSITE_REPORT_EVENT, 120000);

		redist.push_back(probeAddr);

		if (useSSM) {
			if (probeSSMAddrLiteral.empty()) {
				int family = forceFamily;

				if (family == AF_UNSPEC) {
					family = probeAddr.family();
				}
				if (family == AF_INET) {
					probeSSMAddrLiteral = defaultIPv4SSMChannel;
				} else {
					probeSSMAddrLiteral = defaultIPv6SSMChannel;
				}
			}

			if (!ssmProbeAddr.parse(probeSSMAddrLiteral.c_str(), true)) {
				fatal("Bad address format for SSM channel.");
			} else if (!ssmProbeAddr.is_unspecified()) {
				insert_event(SSM_SENDING_EVENT, 100);
				insert_event(SSM_REPORT_EVENT, 15000);

				if (listenForSSM) {
					mcastListen.push_back(ContentDesc(ssmProbeAddr, true));
				}
			}
		}
	} else {
		if (mcastListen.empty())
			fatal("Nothing to do, check `dbeacon -h`.");
		else
			strcpy(sessionName, beaconName.c_str());
	}

	address local;
	local.set_family(probeAddr.family());

	mcastSock = SetupSocket(local, false, false);
	if (mcastSock < 0)
		return -1;

	if (beaconUnicastAddr.is_unspecified())
		beaconUnicastAddr = get_local_address_for(probeAddr);

	if (bind(mcastSock, beaconUnicastAddr.saddr(), beaconUnicastAddr.addrlen()) != 0) {
		perror("Failed to bind local socket");
		return -1;
	}

	if (beaconUnicastAddr.fromsocket(mcastSock) < 0) {
		perror("getsockname");
		return -1;
	}

	for (McastListen::const_iterator i = mcastListen.begin();
			i != mcastListen.end(); ++i) {
		int sock = SetupSocket(i->first, true, i->second);
		if (sock < 0)
			return -1;

//.........这里部分代码省略.........