/*!
Scans an interface and enumerates all baos devices.
It sends a search request as outlined in the BAOS 1.2 protocol
documentation and waits for the responses. There are lots of
magic numbers here and hard-coded offsets... See the spec
for more information on what is happening here...
We implement a receive timeout, and keep receiving until this
timeout elapses. If this timeout is too fast, increase it to 500
or 1000 for example.
*/
void BaosIpEnumerator::scanInterface(const NetworkInterface& networkInterface)
{
poco_information(LOGGER(),
format("Search devices on interface: %s (%s)",
networkInterface.displayName(),
networkInterface.address().toString()));
try
{
// initialize socket
MulticastSocket socket;
socket.bind(SocketAddress(networkInterface.address(), 0));
socket.setTimeToLive(DefaultMulticastTTL);
// builds and sends a SEARCH_REQUEST to the socket
sendSearchRequestFrame(socket);
// wait for SEARCH_RESPONSES and collect it
waitForSearchResponseFrames(socket);
}
catch (Poco::Exception& e)
{
poco_warning(LOGGER(), format("... search failed with error: %s", e.displayText()));
}
}
void MulticastSocket::leaveGroup(const IPAddress& groupAddress, const NetworkInterface& interface)
{
if (groupAddress.af() == AF_INET)
{
struct ip_mreq mr;
std::memcpy(&mr.imr_multiaddr, groupAddress.addr(), groupAddress.length());
std::memcpy(&mr.imr_interface, interface.address().addr(), interface.address().length());
impl()->setRawOption(IPPROTO_IP, IP_DROP_MEMBERSHIP, &mr, sizeof(mr));
}
else
{
#if defined(POCO_HAVE_IPv6)
struct ipv6_mreq mr;
std::memcpy(&mr.ipv6mr_multiaddr, groupAddress.addr(), groupAddress.length());
mr.ipv6mr_interface = interface.index();
impl()->setRawOption(IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mr, sizeof(mr));
#endif
}
}
void MulticastSocket::setInterface(const NetworkInterface& interface)
{
if (!interface.supportsIPv6())
{
impl()->setOption(IPPROTO_IP, IP_MULTICAST_IF, interface.address());
}
else
{
#if defined(POCO_HAVE_IPv6)
impl()->setOption(IPPROTO_IPV6, IPV6_MULTICAST_IF, interface.index());
#endif
}
}