Introduce DvlNet function to read latency data from providers

Source/dvlnet/abstract_net.h

@@ -56,6 +56,11 @@ public:
 		return std::vector<GameInfo>();
 	}
 
+	virtual DvlNetLatencies get_latencies(uint8_t playerid)
+	{
+		return {};
+	}
+
 	static std::unique_ptr<abstract_net> MakeNet(provider_t provider);
 };
 

Source/dvlnet/base.cpp

@@ -33,6 +33,14 @@ void base::clear_password()
 	pktfty = std::make_unique<packet_factory>();
 }
 
+DvlNetLatencies base::get_latencies(uint8_t playerid)
+{
+	DvlNetLatencies latencies = abstract_net::get_latencies(playerid);
+	const PlayerState &playerState = playerStateTable_[playerid];
+	latencies.echoLatency = playerState.roundTripLatency;
+	return latencies;
+}
+
 void base::RunEventHandler(_SNETEVENT &ev)
 {
 	auto f = registered_handlers[static_cast<event_type>(ev.eventid)];

Source/dvlnet/base.h

@@ -39,6 +39,8 @@ public:
 	void setup_password(std::string pw) override;
 	void clear_password() override;
 
+	DvlNetLatencies get_latencies(uint8_t playerid) override;
+
 	~base() override = default;
 
 protected:

Source/dvlnet/base_protocol.h

@@ -37,6 +37,7 @@ public:
 	bool send_info_request() override;
 	void clear_gamelist() override;
 	std::vector<GameInfo> get_gamelist() override;
+	DvlNetLatencies get_latencies(uint8_t playerid) override;
 
 	~base_protocol() override = default;
 
@@ -557,6 +558,16 @@ std::vector<GameInfo> base_protocol<P>::get_gamelist()
 	return ret;
 }
 
+template <class P>
+DvlNetLatencies base_protocol<P>::get_latencies(uint8_t playerid)
+{
+	DvlNetLatencies latencies = base::get_latencies(playerid);
+	Peer &srcPeer = peers[playerid];
+	latencies.providerLatency = proto.get_latency_to(srcPeer.endpoint);
+	latencies.isRelayed = proto.is_peer_relayed(srcPeer.endpoint);
+	return latencies;
+}
+
 template <class P>
 bool base_protocol<P>::SNetLeaveGame(int type)
 {

Source/dvlnet/cdwrap.cpp

@@ -130,4 +130,9 @@ void cdwrap::clear_password()
 	return dvlnet_wrap->clear_password();
 }
 
+DvlNetLatencies cdwrap::get_latencies(uint8_t playerid)
+{
+	return dvlnet_wrap->get_latencies(playerid);
+}
+
 } // namespace devilution::net

Source/dvlnet/cdwrap.h

@@ -52,6 +52,7 @@ public:
 	std::vector<GameInfo> get_gamelist() override;
 	void setup_password(std::string pw) override;
 	void clear_password() override;
+	DvlNetLatencies get_latencies(uint8_t playerid) override;
 
 	virtual ~cdwrap() = default;
 };

Source/dvlnet/protocol_zt.cpp

@@ -1,5 +1,6 @@
 #include "dvlnet/protocol_zt.h"
 
+#include <optional>
 #include <random>
 
 #ifdef USE_SDL3
@@ -26,6 +27,31 @@
 namespace devilution {
 namespace net {
 
+namespace {
+
+bool GetMAC(const protocol_zt::endpoint &peer, uint64_t &mac)
+{
+	ip6_addr_t address = {};
+	IP6_ADDR_PART(&address, 0, peer.addr[0], peer.addr[1], peer.addr[2], peer.addr[3]);
+	IP6_ADDR_PART(&address, 1, peer.addr[4], peer.addr[5], peer.addr[6], peer.addr[7]);
+	IP6_ADDR_PART(&address, 2, peer.addr[8], peer.addr[9], peer.addr[10], peer.addr[11]);
+	IP6_ADDR_PART(&address, 3, peer.addr[12], peer.addr[13], peer.addr[14], peer.addr[15]);
+
+	const u8_t *hwaddr;
+	if (nd6_get_next_hop_addr_or_queue(netif_default, nullptr, &address, &hwaddr) != ERR_OK)
+		return false;
+
+	mac = hwaddr[0];
+	mac = (mac << 8) | hwaddr[1];
+	mac = (mac << 8) | hwaddr[2];
+	mac = (mac << 8) | hwaddr[3];
+	mac = (mac << 8) | hwaddr[4];
+	mac = (mac << 8) | hwaddr[5];
+	return true;
+}
+
+} // namespace
+
 protocol_zt::protocol_zt()
 {
 	zerotier_network_start();
@@ -346,27 +372,22 @@ bool protocol_zt::is_peer_connected(endpoint &peer)
 	return it != peer_list.end() && it->second.fd != -1;
 }
 
-bool protocol_zt::is_peer_relayed(const endpoint &peer) const
+std::optional<bool> protocol_zt::is_peer_relayed(const endpoint &peer) const
 {
-	ip6_addr_t address = {};
-	IP6_ADDR_PART(&address, 0, peer.addr[0], peer.addr[1], peer.addr[2], peer.addr[3]);
-	IP6_ADDR_PART(&address, 1, peer.addr[4], peer.addr[5], peer.addr[6], peer.addr[7]);
-	IP6_ADDR_PART(&address, 2, peer.addr[8], peer.addr[9], peer.addr[10], peer.addr[11]);
-	IP6_ADDR_PART(&address, 3, peer.addr[12], peer.addr[13], peer.addr[14], peer.addr[15]);
-
-	const u8_t *hwaddr;
-	if (nd6_get_next_hop_addr_or_queue(netif_default, nullptr, &address, &hwaddr) != ERR_OK)
-		return true;
-
-	uint64_t mac = hwaddr[0];
-	mac = (mac << 8) | hwaddr[1];
-	mac = (mac << 8) | hwaddr[2];
-	mac = (mac << 8) | hwaddr[3];
-	mac = (mac << 8) | hwaddr[4];
-	mac = (mac << 8) | hwaddr[5];
+	uint64_t mac;
+	if (!GetMAC(peer, mac))
+		return std::nullopt;
 	return zerotier_is_relayed(mac);
 }
 
+std::optional<int> protocol_zt::get_latency_to(const endpoint &peer) const
+{
+	uint64_t mac;
+	if (!GetMAC(peer, mac))
+		return std::nullopt;
+	return zerotier_latency(mac);
+}
+
 std::string protocol_zt::make_default_gamename()
 {
 	std::string ret;

Source/dvlnet/protocol_zt.h

@@ -6,6 +6,7 @@
 #include <cstdint>
 #include <deque>
 #include <exception>
+#include <optional>
 #include <string>
 
 #include <ankerl/unordered_dense.h>
@@ -84,7 +85,8 @@ public:
 	tl::expected<bool, PacketError> network_online();
 	tl::expected<bool, PacketError> peers_ready();
 	bool is_peer_connected(endpoint &peer);
-	bool is_peer_relayed(const endpoint &peer) const;
+	std::optional<bool> is_peer_relayed(const endpoint &peer) const;
+	std::optional<int> get_latency_to(const endpoint &peer) const;
 	static std::string make_default_gamename();
 
 private:

Source/dvlnet/zerotier_native.cpp

@@ -211,5 +211,17 @@ bool zerotier_is_relayed(uint64_t mac)
 	return isRelayed;
 }
 
+int zerotier_latency(uint64_t mac)
+{
+	int latency = -1;
+	if (zts_core_lock_obtain() != ZTS_ERR_OK)
+		return latency;
+	zts_peer_info_t peerInfo;
+	if (zts_core_query_peer_info(ZtNetwork, mac, &peerInfo) == ZTS_ERR_OK)
+		latency = peerInfo.latency;
+	zts_core_lock_release();
+	return latency;
+}
+
 } // namespace net
 } // namespace devilution

Source/dvlnet/zerotier_native.h

@@ -9,6 +9,7 @@ bool zerotier_network_ready();
 bool zerotier_peers_ready();
 void zerotier_network_start();
 bool zerotier_is_relayed(uint64_t mac);
+int zerotier_latency(uint64_t mac);
 
 // NOTE: We have patched our libzt to have the corresponding multicast
 // MAC hardcoded, since libzt is still missing the proper handling.

Source/storm/storm_net.cpp

@@ -15,6 +15,7 @@
 #include "engine/demomode.h"
 #include "headless_mode.hpp"
 #include "menu.h"
+#include "multi.h"
 #include "options.h"
 #include "utils/stubs.h"
 #include "utils/utf8.hpp"
@@ -238,4 +239,9 @@ bool DvlNet_IsPublicGame()
 	return GameIsPublic;
 }
 
+DvlNetLatencies DvlNet_GetLatencies(uint8_t playerId)
+{
+	return dvlnet_inst->get_latencies(playerId);
+}
+
 } // namespace devilution

Source/storm/storm_net.hpp

@@ -2,6 +2,7 @@
 
 #include <cstddef>
 #include <cstdint>
+#include <optional>
 #include <string>
 #include <vector>
 
@@ -42,6 +43,12 @@ struct _SNETEVENT {
 	size_t databytes;  // native-endian
 };
 
+struct DvlNetLatencies {
+	uint32_t echoLatency;
+	std::optional<int> providerLatency;
+	std::optional<bool> isRelayed;
+};
+
 #define PS_CONNECTED 0x10000
 #define PS_TURN_ARRIVED 0x20000
 #define PS_ACTIVE 0x40000
@@ -138,5 +145,6 @@ std::vector<GameInfo> DvlNet_GetGamelist();
 void DvlNet_SetPassword(std::string pw);
 void DvlNet_ClearPassword();
 bool DvlNet_IsPublicGame();
+DvlNetLatencies DvlNet_GetLatencies(uint8_t playerId);
 
 } // namespace devilution