C++ address::to_v4方法代码示例

	void ip_filter::add_rule(address first, address last, int flags)
	{
		if (first.is_v4())
		{
			assert(last.is_v4());
			m_filter4.add_rule(first.to_v4(), last.to_v4(), flags);
		}
		else if (first.is_v6())
		{
			assert(last.is_v6());
			m_filter6.add_rule(first.to_v6(), last.to_v6(), flags);
		}
		else
			assert(false);
	}

	int ip_filter::access(address const& addr) const
	{
		if (addr.is_v4())
			return m_filter4.access(addr.to_v4());
		assert(addr.is_v6());
		return m_filter6.access(addr.to_v6());
	}

	// returns the number of bits in that differ from the right
	// between the addresses.
	int cidr_distance(address const& a1, address const& a2)
	{
		if (a1.is_v4() && a2.is_v4())
		{
			// both are v4
			address_v4::bytes_type b1 = a1.to_v4().to_bytes();
			address_v4::bytes_type b2 = a2.to_v4().to_bytes();
			return address_v4::bytes_type::static_size * 8
				- common_bits(b1.c_array(), b2.c_array(), b1.size());
		}
	
		address_v6::bytes_type b1;
		address_v6::bytes_type b2;
		if (a1.is_v4()) b1 = address_v6::v4_mapped(a1.to_v4()).to_bytes();
		else b1 = a1.to_v6().to_bytes();
		if (a2.is_v4()) b2 = address_v6::v4_mapped(a2.to_v4()).to_bytes();
		else b2 = a2.to_v6().to_bytes();
		return address_v6::bytes_type::static_size * 8
			- common_bits(b1.c_array(), b2.c_array(), b1.size());
	}

	bool in_subnet(address const& addr, ip_interface const& iface)
	{
		if (addr.is_v4() != iface.interface_address.is_v4()) return false;
		// since netmasks seems unreliable for IPv6 interfaces
		// (MacOS X returns AF_INET addresses as bitmasks) assume
		// that any IPv6 address belongs to the subnet of any
		// interface with an IPv6 address
		if (addr.is_v6()) return true;

		return (addr.to_v4().to_ulong() & iface.netmask.to_v4().to_ulong())
			== (iface.interface_address.to_v4().to_ulong() & iface.netmask.to_v4().to_ulong());
	}

    // returns the number of bits in that differ from the right
    // between the addresses. The larger number, the further apart
    // the IPs are
    int cidr_distance(address const& a1, address const& a2)
    {
#if LIBED2K_USE_IPV6
        if (a1.is_v4() && a2.is_v4())
        {
#endif
            // both are v4
            address_v4::bytes_type b1 = a1.to_v4().to_bytes();
            address_v4::bytes_type b2 = a2.to_v4().to_bytes();
            return address_v4::bytes_type().size() * 8 - common_bits(b1.data(), b2.data(), b1.size());
#if LIBED2K_USE_IPV6
        }

        address_v6::bytes_type b1;
        address_v6::bytes_type b2;
        if (a1.is_v4()) b1 = address_v6::v4_mapped(a1.to_v4()).to_bytes();
        else b1 = a1.to_v6().to_bytes();
        if (a2.is_v4()) b2 = address_v6::v4_mapped(a2.to_v4()).to_bytes();
        else b2 = a2.to_v6().to_bytes();
        return address_v6::bytes_type().size() * 8 - common_bits(b1.data(), b2.data(), b1.size());
#endif
    }

		void write_address(address const& a, OutIt& out)
		{
			if (a.is_v4())
			{
				write_uint32(a.to_v4().to_ulong(), out);
			}
			else if (a.is_v6())
			{
				address_v6::bytes_type bytes
					= a.to_v6().to_bytes();
				std::copy(bytes.begin(), bytes.end(), out);
			}
		}

address mask_address(const address& addrIn, uint8_t prefixLen) {
    if (addrIn.is_v4()) {
        prefixLen = std::min<uint8_t>(prefixLen, 32);
        uint32_t mask = get_subnet_mask_v4(prefixLen);
        return address_v4(addrIn.to_v4().to_ulong() & mask);
    }
    struct in6_addr mask;
    struct in6_addr addr6;
    prefixLen = std::min<uint8_t>(prefixLen, 128);
    compute_ipv6_subnet(addrIn.to_v6(), prefixLen, &mask, &addr6);
    address_v6::bytes_type data;
    std::memcpy(data.data(), &addr6, sizeof(addr6));
    return address_v6(data);
}

    std::string address_to_bytes(address const& a)
    {
#if LIBED2K_USE_IPV6
        if (a.is_v6())
        {
            address_v6::bytes_type b = a.to_v6().to_bytes();
            return std::string((char*)&b[0], b.size());
        }
        else
#endif
        {
            address_v4::bytes_type b = a.to_v4().to_bytes();
            return std::string((char*)&b[0], b.size());
        }
    }

		void write_address(address const& a, OutIt&& out)
		{
#if TORRENT_USE_IPV6
			if (a.is_v4())
			{
#endif
				write_uint32(a.to_v4().to_ulong(), out);
#if TORRENT_USE_IPV6
			}
			else if (a.is_v6())
			{
				for (auto b : a.to_v6().to_bytes())
					write_uint8(b, out);
			}
#endif
		}

		void write_address(address const& a, OutIt& out)
		{
#if TORRENT_USE_IPV6
			if (a.is_v4())
			{
#endif
				write_uint32(a.to_v4().to_ulong(), out);
#if TORRENT_USE_IPV6
			}
			else if (a.is_v6())
			{
				address_v6::bytes_type bytes
					= a.to_v6().to_bytes();
				std::copy(bytes.begin(), bytes.end(), out);
			}
#endif
		}

		void write_address(address const& a, OutIt& out)
		{
#if TORRENT_USE_IPV6
			if (a.is_v4())
			{
#endif
				write_uint32(a.to_v4().to_ulong(), out);
#if TORRENT_USE_IPV6
			}
			else if (a.is_v6())
			{
				typedef address_v6::bytes_type bytes_t;
				bytes_t bytes = a.to_v6().to_bytes();
				for (bytes_t::iterator i = bytes.begin()
					, end(bytes.end()); i != end; ++i)
					write_uint8(*i, out);
			}
#endif
		}

void natpmp::rebind(address const& listen_interface) try
{
	address_v4 local = address_v4::any();
	if (listen_interface.is_v4() && listen_interface != address_v4::any())
	{
		local = listen_interface.to_v4();
	}
	else
	{
		local = guess_local_address(m_socket.io_service());

		if (local == address_v4::any())
		{
			throw std::runtime_error("local host is probably not on a NATed "
				"network. disabling NAT-PMP");
		}
	}

#if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING)
	m_log << time_now_string()
		<< " local ip: " << local.to_string() << std::endl;
#endif

	if (!is_local(local))
	{
		// the local address seems to be an external
		// internet address. Assume it is not behind a NAT
		throw std::runtime_error("local IP is not on a local network");
	}

	m_disabled = false;

	// assume the router is located on the local
	// network as x.x.x.1
	udp::endpoint nat_endpoint(
		address_v4((local.to_ulong() & 0xffffff00) | 1), 5351);

	if (nat_endpoint == m_nat_endpoint) return;

	// TODO: find a better way to figure out the router IP
	m_nat_endpoint = nat_endpoint;

#if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING)
	m_log << "assuming router is at: " << m_nat_endpoint.address().to_string() << std::endl;
#endif

	m_socket.open(udp::v4());
	m_socket.bind(udp::endpoint(address_v4::any(), 0));

	for (int i = 0; i < num_mappings; ++i)
	{
		if (m_mappings[i].local_port == 0)
			continue;
		refresh_mapping(i);
	}
}
catch (std::exception& e)
{
	m_disabled = true;
	std::stringstream msg;
	msg << "NAT-PMP disabled: " << e.what();
#if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING)
	m_log << msg.str() << std::endl;
#endif
	m_callback(0, 0, msg.str());
};