public:

enum class Policy : uint8_t {

// Ignore the server-advertised preferred address.

IGNORE_PREFERRED,

// Use the server-advertised preferred address.

USE_PREFERRED,

};

static v8::Maybe<Policy> tryGetPolicy(Environment* env,

v8::Local<v8::Value> value);

static inline v8::Maybe<Policy> tryGetPolicy(Realm* realm,

v8::Local<v8::Value> value) {

return tryGetPolicy(realm->env(), value);

}

static void Initialize(Environment* env, v8::Local<v8::Object> target);

static inline void Initialize(Realm* realm, v8::Local<v8::Object> target) {

return Initialize(realm->env(), target);

}

struct AddressInfo final {

char host[NI_MAXHOST];

int family;

uint16_t port;

};

explicit PreferredAddress(ngtcp2_path* dest,

const ngtcp2_preferred_addr* paddr);

DISALLOW_COPY_AND_MOVE(PreferredAddress)

void* operator new(size_t) = delete;

void operator delete(void*) = delete;

void Use(const AddressInfo& address);

std::optional<const AddressInfo> ipv4() const;

std::optional<const AddressInfo> ipv6() const;

const CID cid() const;

// Set the preferred address in the transport params.

// The address family (ipv4 or ipv6) will be automatically

// detected from the given addr. Any other address family

// will be ignored.

static void Set(ngtcp2_transport_params* params, const sockaddr* addr);

private:

ngtcp2_path* dest_;

const ngtcp2_preferred_addr* paddr_;