Fixes for PR #96 (#170)

* Implement basic multiplayer functionality

* Update README.md

---------

Co-authored-by: Slenderman <ssimulpong@outlook.com>

1 files changed, 844 insertions, 0 deletions

diff --git a/Minecraft.Client/Windows64/Network/WinsockNetLayer.cpp b/Minecraft.Client/Windows64/Network/WinsockNetLayer.cpp
new file mode 100644
index 00000000..19fc2598
--- /dev/null
+++ b/Minecraft.Client/Windows64/Network/WinsockNetLayer.cpp
@@ -0,0 +1,844 @@
+#include "stdafx.h"
+
+#ifdef _WINDOWS64
+
+#include "WinsockNetLayer.h"
+#include "..\..\Common\Network\PlatformNetworkManagerStub.h"
+#include "..\..\..\Minecraft.World\Socket.h"
+
+SOCKET WinsockNetLayer::s_listenSocket = INVALID_SOCKET;
+SOCKET WinsockNetLayer::s_hostConnectionSocket = INVALID_SOCKET;
+HANDLE WinsockNetLayer::s_acceptThread = NULL;
+HANDLE WinsockNetLayer::s_clientRecvThread = NULL;
+
+bool WinsockNetLayer::s_isHost = false;
+bool WinsockNetLayer::s_connected = false;
+bool WinsockNetLayer::s_active = false;
+bool WinsockNetLayer::s_initialized = false;
+
+BYTE WinsockNetLayer::s_localSmallId = 0;
+BYTE WinsockNetLayer::s_hostSmallId = 0;
+BYTE WinsockNetLayer::s_nextSmallId = 1;
+
+CRITICAL_SECTION WinsockNetLayer::s_sendLock;
+CRITICAL_SECTION WinsockNetLayer::s_connectionsLock;
+
+std::vector<Win64RemoteConnection> WinsockNetLayer::s_connections;
+
+SOCKET WinsockNetLayer::s_advertiseSock = INVALID_SOCKET;
+HANDLE WinsockNetLayer::s_advertiseThread = NULL;
+volatile bool WinsockNetLayer::s_advertising = false;
+Win64LANBroadcast WinsockNetLayer::s_advertiseData = {};
+CRITICAL_SECTION WinsockNetLayer::s_advertiseLock;
+int WinsockNetLayer::s_hostGamePort = WIN64_NET_DEFAULT_PORT;
+
+SOCKET WinsockNetLayer::s_discoverySock = INVALID_SOCKET;
+HANDLE WinsockNetLayer::s_discoveryThread = NULL;
+volatile bool WinsockNetLayer::s_discovering = false;
+CRITICAL_SECTION WinsockNetLayer::s_discoveryLock;
+std::vector<Win64LANSession> WinsockNetLayer::s_discoveredSessions;
+
+CRITICAL_SECTION WinsockNetLayer::s_disconnectLock;
+std::vector<BYTE> WinsockNetLayer::s_disconnectedSmallIds;
+
+CRITICAL_SECTION WinsockNetLayer::s_freeSmallIdLock;
+std::vector<BYTE> WinsockNetLayer::s_freeSmallIds;
+
+bool g_Win64MultiplayerHost = false;
+bool g_Win64MultiplayerJoin = false;
+int g_Win64MultiplayerPort = WIN64_NET_DEFAULT_PORT;
+char g_Win64MultiplayerIP[256] = "127.0.0.1";
+
+bool WinsockNetLayer::Initialize()
+{
+	if (s_initialized) return true;
+
+	WSADATA wsaData;
+	int result = WSAStartup(MAKEWORD(2, 2), &wsaData);
+	if (result != 0)
+	{
+		app.DebugPrintf("WSAStartup failed: %d\n", result);
+		return false;
+	}
+
+	InitializeCriticalSection(&s_sendLock);
+	InitializeCriticalSection(&s_connectionsLock);
+	InitializeCriticalSection(&s_advertiseLock);
+	InitializeCriticalSection(&s_discoveryLock);
+	InitializeCriticalSection(&s_disconnectLock);
+	InitializeCriticalSection(&s_freeSmallIdLock);
+
+	s_initialized = true;
+
+	StartDiscovery();
+
+	return true;
+}
+
+void WinsockNetLayer::Shutdown()
+{
+	StopAdvertising();
+	StopDiscovery();
+
+	s_active = false;
+	s_connected = false;
+
+	if (s_listenSocket != INVALID_SOCKET)
+	{
+		closesocket(s_listenSocket);
+		s_listenSocket = INVALID_SOCKET;
+	}
+
+	if (s_hostConnectionSocket != INVALID_SOCKET)
+	{
+		closesocket(s_hostConnectionSocket);
+		s_hostConnectionSocket = INVALID_SOCKET;
+	}
+
+	EnterCriticalSection(&s_connectionsLock);
+	for (size_t i = 0; i < s_connections.size(); i++)
+	{
+		s_connections[i].active = false;
+		if (s_connections[i].tcpSocket != INVALID_SOCKET)
+		{
+			closesocket(s_connections[i].tcpSocket);
+		}
+	}
+	s_connections.clear();
+	LeaveCriticalSection(&s_connectionsLock);
+
+	if (s_acceptThread != NULL)
+	{
+		WaitForSingleObject(s_acceptThread, 2000);
+		CloseHandle(s_acceptThread);
+		s_acceptThread = NULL;
+	}
+
+	if (s_clientRecvThread != NULL)
+	{
+		WaitForSingleObject(s_clientRecvThread, 2000);
+		CloseHandle(s_clientRecvThread);
+		s_clientRecvThread = NULL;
+	}
+
+	if (s_initialized)
+	{
+		DeleteCriticalSection(&s_sendLock);
+		DeleteCriticalSection(&s_connectionsLock);
+		DeleteCriticalSection(&s_advertiseLock);
+		DeleteCriticalSection(&s_discoveryLock);
+		DeleteCriticalSection(&s_disconnectLock);
+		s_disconnectedSmallIds.clear();
+		DeleteCriticalSection(&s_freeSmallIdLock);
+		s_freeSmallIds.clear();
+		WSACleanup();
+		s_initialized = false;
+	}
+}
+
+bool WinsockNetLayer::HostGame(int port)
+{
+	if (!s_initialized && !Initialize()) return false;
+
+	s_isHost = true;
+	s_localSmallId = 0;
+	s_hostSmallId = 0;
+	s_nextSmallId = 1;
+	s_hostGamePort = port;
+
+	EnterCriticalSection(&s_freeSmallIdLock);
+	s_freeSmallIds.clear();
+	LeaveCriticalSection(&s_freeSmallIdLock);
+
+	struct addrinfo hints = {};
+	struct addrinfo *result = NULL;
+
+	hints.ai_family = AF_INET;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_protocol = IPPROTO_TCP;
+	hints.ai_flags = AI_PASSIVE;
+
+	char portStr[16];
+	sprintf_s(portStr, "%d", port);
+
+	int iResult = getaddrinfo(NULL, portStr, &hints, &result);
+	if (iResult != 0)
+	{
+		app.DebugPrintf("getaddrinfo failed: %d\n", iResult);
+		return false;
+	}
+
+	s_listenSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
+	if (s_listenSocket == INVALID_SOCKET)
+	{
+		app.DebugPrintf("socket() failed: %d\n", WSAGetLastError());
+		freeaddrinfo(result);
+		return false;
+	}
+
+	int opt = 1;
+	setsockopt(s_listenSocket, SOL_SOCKET, SO_REUSEADDR, (const char *)&opt, sizeof(opt));
+
+	iResult = ::bind(s_listenSocket, result->ai_addr, (int)result->ai_addrlen);
+	freeaddrinfo(result);
+	if (iResult == SOCKET_ERROR)
+	{
+		app.DebugPrintf("bind() failed: %d\n", WSAGetLastError());
+		closesocket(s_listenSocket);
+		s_listenSocket = INVALID_SOCKET;
+		return false;
+	}
+
+	iResult = listen(s_listenSocket, SOMAXCONN);
+	if (iResult == SOCKET_ERROR)
+	{
+		app.DebugPrintf("listen() failed: %d\n", WSAGetLastError());
+		closesocket(s_listenSocket);
+		s_listenSocket = INVALID_SOCKET;
+		return false;
+	}
+
+	s_active = true;
+	s_connected = true;
+
+	s_acceptThread = CreateThread(NULL, 0, AcceptThreadProc, NULL, 0, NULL);
+
+	app.DebugPrintf("Win64 LAN: Hosting on port %d\n", port);
+	return true;
+}
+
+bool WinsockNetLayer::JoinGame(const char *ip, int port)
+{
+	if (!s_initialized && !Initialize()) return false;
+
+	s_isHost = false;
+	s_hostSmallId = 0;
+
+	struct addrinfo hints = {};
+	struct addrinfo *result = NULL;
+
+	hints.ai_family = AF_INET;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_protocol = IPPROTO_TCP;
+
+	char portStr[16];
+	sprintf_s(portStr, "%d", port);
+
+	int iResult = getaddrinfo(ip, portStr, &hints, &result);
+	if (iResult != 0)
+	{
+		app.DebugPrintf("getaddrinfo failed for %s:%d - %d\n", ip, port, iResult);
+		return false;
+	}
+
+	s_hostConnectionSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
+	if (s_hostConnectionSocket == INVALID_SOCKET)
+	{
+		app.DebugPrintf("socket() failed: %d\n", WSAGetLastError());
+		freeaddrinfo(result);
+		return false;
+	}
+
+	int noDelay = 1;
+	setsockopt(s_hostConnectionSocket, IPPROTO_TCP, TCP_NODELAY, (const char *)&noDelay, sizeof(noDelay));
+
+	iResult = connect(s_hostConnectionSocket, result->ai_addr, (int)result->ai_addrlen);
+	freeaddrinfo(result);
+	if (iResult == SOCKET_ERROR)
+	{
+		app.DebugPrintf("connect() to %s:%d failed: %d\n", ip, port, WSAGetLastError());
+		closesocket(s_hostConnectionSocket);
+		s_hostConnectionSocket = INVALID_SOCKET;
+		return false;
+	}
+
+	BYTE assignBuf[1];
+	int bytesRecv = recv(s_hostConnectionSocket, (char *)assignBuf, 1, 0);
+	if (bytesRecv != 1)
+	{
+		app.DebugPrintf("Failed to receive small ID assignment from host\n");
+		closesocket(s_hostConnectionSocket);
+		s_hostConnectionSocket = INVALID_SOCKET;
+		return false;
+	}
+	s_localSmallId = assignBuf[0];
+
+	app.DebugPrintf("Win64 LAN: Connected to %s:%d, assigned smallId=%d\n", ip, port, s_localSmallId);
+
+	s_active = true;
+	s_connected = true;
+
+	s_clientRecvThread = CreateThread(NULL, 0, ClientRecvThreadProc, NULL, 0, NULL);
+
+	return true;
+}
+
+bool WinsockNetLayer::SendOnSocket(SOCKET sock, const void *data, int dataSize)
+{
+	if (sock == INVALID_SOCKET || dataSize <= 0) return false;
+
+	EnterCriticalSection(&s_sendLock);
+
+	BYTE header[4];
+	header[0] = (BYTE)((dataSize >> 24) & 0xFF);
+	header[1] = (BYTE)((dataSize >> 16) & 0xFF);
+	header[2] = (BYTE)((dataSize >> 8) & 0xFF);
+	header[3] = (BYTE)(dataSize & 0xFF);
+
+	int totalSent = 0;
+	int toSend = 4;
+	while (totalSent < toSend)
+	{
+		int sent = send(sock, (const char *)header + totalSent, toSend - totalSent, 0);
+		if (sent == SOCKET_ERROR || sent == 0)
+		{
+			LeaveCriticalSection(&s_sendLock);
+			return false;
+		}
+		totalSent += sent;
+	}
+
+	totalSent = 0;
+	while (totalSent < dataSize)
+	{
+		int sent = send(sock, (const char *)data + totalSent, dataSize - totalSent, 0);
+		if (sent == SOCKET_ERROR || sent == 0)
+		{
+			LeaveCriticalSection(&s_sendLock);
+			return false;
+		}
+		totalSent += sent;
+	}
+
+	LeaveCriticalSection(&s_sendLock);
+	return true;
+}
+
+bool WinsockNetLayer::SendToSmallId(BYTE targetSmallId, const void *data, int dataSize)
+{
+	if (!s_active) return false;
+
+	if (s_isHost)
+	{
+		SOCKET sock = GetSocketForSmallId(targetSmallId);
+		if (sock == INVALID_SOCKET) return false;
+		return SendOnSocket(sock, data, dataSize);
+	}
+	else
+	{
+		return SendOnSocket(s_hostConnectionSocket, data, dataSize);
+	}
+}
+
+SOCKET WinsockNetLayer::GetSocketForSmallId(BYTE smallId)
+{
+	EnterCriticalSection(&s_connectionsLock);
+	for (size_t i = 0; i < s_connections.size(); i++)
+	{
+		if (s_connections[i].smallId == smallId && s_connections[i].active)
+		{
+			SOCKET sock = s_connections[i].tcpSocket;
+			LeaveCriticalSection(&s_connectionsLock);
+			return sock;
+		}
+	}
+	LeaveCriticalSection(&s_connectionsLock);
+	return INVALID_SOCKET;
+}
+
+static bool RecvExact(SOCKET sock, BYTE *buf, int len)
+{
+	int totalRecv = 0;
+	while (totalRecv < len)
+	{
+		int r = recv(sock, (char *)buf + totalRecv, len - totalRecv, 0);
+		if (r <= 0) return false;
+		totalRecv += r;
+	}
+	return true;
+}
+
+void WinsockNetLayer::HandleDataReceived(BYTE fromSmallId, BYTE toSmallId, unsigned char *data, unsigned int dataSize)
+{
+	INetworkPlayer *pPlayerFrom = g_NetworkManager.GetPlayerBySmallId(fromSmallId);
+	INetworkPlayer *pPlayerTo = g_NetworkManager.GetPlayerBySmallId(toSmallId);
+
+	if (pPlayerFrom == NULL || pPlayerTo == NULL) return;
+
+	if (s_isHost)
+	{
+		::Socket *pSocket = pPlayerFrom->GetSocket();
+		if (pSocket != NULL)
+			pSocket->pushDataToQueue(data, dataSize, false);
+	}
+	else
+	{
+		::Socket *pSocket = pPlayerTo->GetSocket();
+		if (pSocket != NULL)
+			pSocket->pushDataToQueue(data, dataSize, true);
+	}
+}
+
+DWORD WINAPI WinsockNetLayer::AcceptThreadProc(LPVOID param)
+{
+	while (s_active)
+	{
+		SOCKET clientSocket = accept(s_listenSocket, NULL, NULL);
+		if (clientSocket == INVALID_SOCKET)
+		{
+			if (s_active)
+				app.DebugPrintf("accept() failed: %d\n", WSAGetLastError());
+			break;
+		}
+
+		int noDelay = 1;
+		setsockopt(clientSocket, IPPROTO_TCP, TCP_NODELAY, (const char *)&noDelay, sizeof(noDelay));
+
+		extern QNET_STATE _iQNetStubState;
+		if (_iQNetStubState != QNET_STATE_GAME_PLAY)
+		{
+			app.DebugPrintf("Win64 LAN: Rejecting connection, game not ready\n");
+			closesocket(clientSocket);
+			continue;
+		}
+
+		BYTE assignedSmallId;
+		EnterCriticalSection(&s_freeSmallIdLock);
+		if (!s_freeSmallIds.empty())
+		{
+			assignedSmallId = s_freeSmallIds.back();
+			s_freeSmallIds.pop_back();
+		}
+		else if (s_nextSmallId < MINECRAFT_NET_MAX_PLAYERS)
+		{
+			assignedSmallId = s_nextSmallId++;
+		}
+		else
+		{
+			LeaveCriticalSection(&s_freeSmallIdLock);
+			app.DebugPrintf("Win64 LAN: Server full, rejecting connection\n");
+			closesocket(clientSocket);
+			continue;
+		}
+		LeaveCriticalSection(&s_freeSmallIdLock);
+
+		BYTE assignBuf[1] = { assignedSmallId };
+		int sent = send(clientSocket, (const char *)assignBuf, 1, 0);
+		if (sent != 1)
+		{
+			app.DebugPrintf("Failed to send small ID to client\n");
+			closesocket(clientSocket);
+			continue;
+		}
+
+		Win64RemoteConnection conn;
+		conn.tcpSocket = clientSocket;
+		conn.smallId = assignedSmallId;
+		conn.active = true;
+		conn.recvThread = NULL;
+
+		EnterCriticalSection(&s_connectionsLock);
+		s_connections.push_back(conn);
+		int connIdx = (int)s_connections.size() - 1;
+		LeaveCriticalSection(&s_connectionsLock);
+
+		app.DebugPrintf("Win64 LAN: Client connected, assigned smallId=%d\n", assignedSmallId);
+
+		IQNetPlayer *qnetPlayer = &IQNet::m_player[assignedSmallId];
+
+		extern void Win64_SetupRemoteQNetPlayer(IQNetPlayer *player, BYTE smallId, bool isHost, bool isLocal);
+		Win64_SetupRemoteQNetPlayer(qnetPlayer, assignedSmallId, false, false);
+
+		extern CPlatformNetworkManagerStub *g_pPlatformNetworkManager;
+		g_pPlatformNetworkManager->NotifyPlayerJoined(qnetPlayer);
+
+		DWORD *threadParam = new DWORD;
+		*threadParam = connIdx;
+		HANDLE hThread = CreateThread(NULL, 0, RecvThreadProc, threadParam, 0, NULL);
+
+		EnterCriticalSection(&s_connectionsLock);
+		if (connIdx < (int)s_connections.size())
+			s_connections[connIdx].recvThread = hThread;
+		LeaveCriticalSection(&s_connectionsLock);
+	}
+	return 0;
+}
+
+DWORD WINAPI WinsockNetLayer::RecvThreadProc(LPVOID param)
+{
+	DWORD connIdx = *(DWORD *)param;
+	delete (DWORD *)param;
+
+	EnterCriticalSection(&s_connectionsLock);
+	if (connIdx >= (DWORD)s_connections.size())
+	{
+		LeaveCriticalSection(&s_connectionsLock);
+		return 0;
+	}
+	SOCKET sock = s_connections[connIdx].tcpSocket;
+	BYTE clientSmallId = s_connections[connIdx].smallId;
+	LeaveCriticalSection(&s_connectionsLock);
+
+	BYTE *recvBuf = new BYTE[WIN64_NET_RECV_BUFFER_SIZE];
+
+	while (s_active)
+	{
+		BYTE header[4];
+		if (!RecvExact(sock, header, 4))
+		{
+			app.DebugPrintf("Win64 LAN: Client smallId=%d disconnected (header)\n", clientSmallId);
+			break;
+		}
+
+		int packetSize = (header[0] << 24) | (header[1] << 16) | (header[2] << 8) | header[3];
+
+		if (packetSize <= 0 || packetSize > WIN64_NET_RECV_BUFFER_SIZE)
+		{
+			app.DebugPrintf("Win64 LAN: Invalid packet size %d from client smallId=%d\n", packetSize, clientSmallId);
+			break;
+		}
+
+		if (!RecvExact(sock, recvBuf, packetSize))
+		{
+			app.DebugPrintf("Win64 LAN: Client smallId=%d disconnected (body)\n", clientSmallId);
+			break;
+		}
+
+		HandleDataReceived(clientSmallId, s_hostSmallId, recvBuf, packetSize);
+	}
+
+	delete[] recvBuf;
+
+	EnterCriticalSection(&s_connectionsLock);
+	for (size_t i = 0; i < s_connections.size(); i++)
+	{
+		if (s_connections[i].smallId == clientSmallId)
+		{
+			s_connections[i].active = false;
+			closesocket(s_connections[i].tcpSocket);
+			s_connections[i].tcpSocket = INVALID_SOCKET;
+			break;
+		}
+	}
+	LeaveCriticalSection(&s_connectionsLock);
+
+	EnterCriticalSection(&s_disconnectLock);
+	s_disconnectedSmallIds.push_back(clientSmallId);
+	LeaveCriticalSection(&s_disconnectLock);
+
+	return 0;
+}
+
+bool WinsockNetLayer::PopDisconnectedSmallId(BYTE *outSmallId)
+{
+	bool found = false;
+	EnterCriticalSection(&s_disconnectLock);
+	if (!s_disconnectedSmallIds.empty())
+	{
+		*outSmallId = s_disconnectedSmallIds.back();
+		s_disconnectedSmallIds.pop_back();
+		found = true;
+	}
+	LeaveCriticalSection(&s_disconnectLock);
+	return found;
+}
+
+void WinsockNetLayer::PushFreeSmallId(BYTE smallId)
+{
+	EnterCriticalSection(&s_freeSmallIdLock);
+	s_freeSmallIds.push_back(smallId);
+	LeaveCriticalSection(&s_freeSmallIdLock);
+}
+
+DWORD WINAPI WinsockNetLayer::ClientRecvThreadProc(LPVOID param)
+{
+	BYTE *recvBuf = new BYTE[WIN64_NET_RECV_BUFFER_SIZE];
+
+	while (s_active && s_hostConnectionSocket != INVALID_SOCKET)
+	{
+		BYTE header[4];
+		if (!RecvExact(s_hostConnectionSocket, header, 4))
+		{
+			app.DebugPrintf("Win64 LAN: Disconnected from host (header)\n");
+			break;
+		}
+
+		int packetSize = (header[0] << 24) | (header[1] << 16) | (header[2] << 8) | header[3];
+
+		if (packetSize <= 0 || packetSize > WIN64_NET_RECV_BUFFER_SIZE)
+		{
+			app.DebugPrintf("Win64 LAN: Invalid packet size %d from host\n", packetSize);
+			break;
+		}
+
+		if (!RecvExact(s_hostConnectionSocket, recvBuf, packetSize))
+		{
+			app.DebugPrintf("Win64 LAN: Disconnected from host (body)\n");
+			break;
+		}
+
+		HandleDataReceived(s_hostSmallId, s_localSmallId, recvBuf, packetSize);
+	}
+
+	delete[] recvBuf;
+
+	s_connected = false;
+	return 0;
+}
+
+bool WinsockNetLayer::StartAdvertising(int gamePort, const wchar_t *hostName, unsigned int gameSettings, unsigned int texPackId, unsigned char subTexId, unsigned short netVer)
+{
+	if (s_advertising) return true;
+	if (!s_initialized) return false;
+
+	EnterCriticalSection(&s_advertiseLock);
+	memset(&s_advertiseData, 0, sizeof(s_advertiseData));
+	s_advertiseData.magic = WIN64_LAN_BROADCAST_MAGIC;
+	s_advertiseData.netVersion = netVer;
+	s_advertiseData.gamePort = (WORD)gamePort;
+	wcsncpy_s(s_advertiseData.hostName, 32, hostName, _TRUNCATE);
+	s_advertiseData.playerCount = 1;
+	s_advertiseData.maxPlayers = MINECRAFT_NET_MAX_PLAYERS;
+	s_advertiseData.gameHostSettings = gameSettings;
+	s_advertiseData.texturePackParentId = texPackId;
+	s_advertiseData.subTexturePackId = subTexId;
+	s_advertiseData.isJoinable = 0;
+	s_hostGamePort = gamePort;
+	LeaveCriticalSection(&s_advertiseLock);
+
+	s_advertiseSock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (s_advertiseSock == INVALID_SOCKET)
+	{
+		app.DebugPrintf("Win64 LAN: Failed to create advertise socket: %d\n", WSAGetLastError());
+		return false;
+	}
+
+	BOOL broadcast = TRUE;
+	setsockopt(s_advertiseSock, SOL_SOCKET, SO_BROADCAST, (const char *)&broadcast, sizeof(broadcast));
+
+	s_advertising = true;
+	s_advertiseThread = CreateThread(NULL, 0, AdvertiseThreadProc, NULL, 0, NULL);
+
+	app.DebugPrintf("Win64 LAN: Started advertising on UDP port %d\n", WIN64_LAN_DISCOVERY_PORT);
+	return true;
+}
+
+void WinsockNetLayer::StopAdvertising()
+{
+	s_advertising = false;
+
+	if (s_advertiseSock != INVALID_SOCKET)
+	{
+		closesocket(s_advertiseSock);
+		s_advertiseSock = INVALID_SOCKET;
+	}
+
+	if (s_advertiseThread != NULL)
+	{
+		WaitForSingleObject(s_advertiseThread, 2000);
+		CloseHandle(s_advertiseThread);
+		s_advertiseThread = NULL;
+	}
+}
+
+void WinsockNetLayer::UpdateAdvertisePlayerCount(BYTE count)
+{
+	EnterCriticalSection(&s_advertiseLock);
+	s_advertiseData.playerCount = count;
+	LeaveCriticalSection(&s_advertiseLock);
+}
+
+void WinsockNetLayer::UpdateAdvertiseJoinable(bool joinable)
+{
+	EnterCriticalSection(&s_advertiseLock);
+	s_advertiseData.isJoinable = joinable ? 1 : 0;
+	LeaveCriticalSection(&s_advertiseLock);
+}
+
+DWORD WINAPI WinsockNetLayer::AdvertiseThreadProc(LPVOID param)
+{
+	struct sockaddr_in broadcastAddr;
+	memset(&broadcastAddr, 0, sizeof(broadcastAddr));
+	broadcastAddr.sin_family = AF_INET;
+	broadcastAddr.sin_port = htons(WIN64_LAN_DISCOVERY_PORT);
+	broadcastAddr.sin_addr.s_addr = INADDR_BROADCAST;
+
+	while (s_advertising)
+	{
+		EnterCriticalSection(&s_advertiseLock);
+		Win64LANBroadcast data = s_advertiseData;
+		LeaveCriticalSection(&s_advertiseLock);
+
+		int sent = sendto(s_advertiseSock, (const char *)&data, sizeof(data), 0,
+			(struct sockaddr *)&broadcastAddr, sizeof(broadcastAddr));
+
+		if (sent == SOCKET_ERROR && s_advertising)
+		{
+			app.DebugPrintf("Win64 LAN: Broadcast sendto failed: %d\n", WSAGetLastError());
+		}
+
+		Sleep(1000);
+	}
+
+	return 0;
+}
+
+bool WinsockNetLayer::StartDiscovery()
+{
+	if (s_discovering) return true;
+	if (!s_initialized) return false;
+
+	s_discoverySock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (s_discoverySock == INVALID_SOCKET)
+	{
+		app.DebugPrintf("Win64 LAN: Failed to create discovery socket: %d\n", WSAGetLastError());
+		return false;
+	}
+
+	BOOL reuseAddr = TRUE;
+	setsockopt(s_discoverySock, SOL_SOCKET, SO_REUSEADDR, (const char *)&reuseAddr, sizeof(reuseAddr));
+
+	struct sockaddr_in bindAddr;
+	memset(&bindAddr, 0, sizeof(bindAddr));
+	bindAddr.sin_family = AF_INET;
+	bindAddr.sin_port = htons(WIN64_LAN_DISCOVERY_PORT);
+	bindAddr.sin_addr.s_addr = INADDR_ANY;
+
+	if (::bind(s_discoverySock, (struct sockaddr *)&bindAddr, sizeof(bindAddr)) == SOCKET_ERROR)
+	{
+		app.DebugPrintf("Win64 LAN: Discovery bind failed: %d\n", WSAGetLastError());
+		closesocket(s_discoverySock);
+		s_discoverySock = INVALID_SOCKET;
+		return false;
+	}
+
+	DWORD timeout = 500;
+	setsockopt(s_discoverySock, SOL_SOCKET, SO_RCVTIMEO, (const char *)&timeout, sizeof(timeout));
+
+	s_discovering = true;
+	s_discoveryThread = CreateThread(NULL, 0, DiscoveryThreadProc, NULL, 0, NULL);
+
+	app.DebugPrintf("Win64 LAN: Listening for LAN games on UDP port %d\n", WIN64_LAN_DISCOVERY_PORT);
+	return true;
+}
+
+void WinsockNetLayer::StopDiscovery()
+{
+	s_discovering = false;
+
+	if (s_discoverySock != INVALID_SOCKET)
+	{
+		closesocket(s_discoverySock);
+		s_discoverySock = INVALID_SOCKET;
+	}
+
+	if (s_discoveryThread != NULL)
+	{
+		WaitForSingleObject(s_discoveryThread, 2000);
+		CloseHandle(s_discoveryThread);
+		s_discoveryThread = NULL;
+	}
+
+	EnterCriticalSection(&s_discoveryLock);
+	s_discoveredSessions.clear();
+	LeaveCriticalSection(&s_discoveryLock);
+}
+
+std::vector<Win64LANSession> WinsockNetLayer::GetDiscoveredSessions()
+{
+	std::vector<Win64LANSession> result;
+	EnterCriticalSection(&s_discoveryLock);
+	result = s_discoveredSessions;
+	LeaveCriticalSection(&s_discoveryLock);
+	return result;
+}
+
+DWORD WINAPI WinsockNetLayer::DiscoveryThreadProc(LPVOID param)
+{
+	char recvBuf[512];
+
+	while (s_discovering)
+	{
+		struct sockaddr_in senderAddr;
+		int senderLen = sizeof(senderAddr);
+
+		int recvLen = recvfrom(s_discoverySock, recvBuf, sizeof(recvBuf), 0,
+			(struct sockaddr *)&senderAddr, &senderLen);
+
+		if (recvLen == SOCKET_ERROR)
+		{
+			continue;
+		}
+
+		if (recvLen < (int)sizeof(Win64LANBroadcast))
+			continue;
+
+		Win64LANBroadcast *broadcast = (Win64LANBroadcast *)recvBuf;
+		if (broadcast->magic != WIN64_LAN_BROADCAST_MAGIC)
+			continue;
+
+		char senderIP[64];
+		inet_ntop(AF_INET, &senderAddr.sin_addr, senderIP, sizeof(senderIP));
+
+		DWORD now = GetTickCount();
+
+		EnterCriticalSection(&s_discoveryLock);
+
+		bool found = false;
+		for (size_t i = 0; i < s_discoveredSessions.size(); i++)
+		{
+			if (strcmp(s_discoveredSessions[i].hostIP, senderIP) == 0 &&
+				s_discoveredSessions[i].hostPort == (int)broadcast->gamePort)
+			{
+				s_discoveredSessions[i].netVersion = broadcast->netVersion;
+				wcsncpy_s(s_discoveredSessions[i].hostName, 32, broadcast->hostName, _TRUNCATE);
+				s_discoveredSessions[i].playerCount = broadcast->playerCount;
+				s_discoveredSessions[i].maxPlayers = broadcast->maxPlayers;
+				s_discoveredSessions[i].gameHostSettings = broadcast->gameHostSettings;
+				s_discoveredSessions[i].texturePackParentId = broadcast->texturePackParentId;
+				s_discoveredSessions[i].subTexturePackId = broadcast->subTexturePackId;
+				s_discoveredSessions[i].isJoinable = (broadcast->isJoinable != 0);
+				s_discoveredSessions[i].lastSeenTick = now;
+				found = true;
+				break;
+			}
+		}
+
+		if (!found)
+		{
+			Win64LANSession session;
+			memset(&session, 0, sizeof(session));
+			strncpy_s(session.hostIP, sizeof(session.hostIP), senderIP, _TRUNCATE);
+			session.hostPort = (int)broadcast->gamePort;
+			session.netVersion = broadcast->netVersion;
+			wcsncpy_s(session.hostName, 32, broadcast->hostName, _TRUNCATE);
+			session.playerCount = broadcast->playerCount;
+			session.maxPlayers = broadcast->maxPlayers;
+			session.gameHostSettings = broadcast->gameHostSettings;
+			session.texturePackParentId = broadcast->texturePackParentId;
+			session.subTexturePackId = broadcast->subTexturePackId;
+			session.isJoinable = (broadcast->isJoinable != 0);
+			session.lastSeenTick = now;
+			s_discoveredSessions.push_back(session);
+
+			app.DebugPrintf("Win64 LAN: Discovered game \"%ls\" at %s:%d\n",
+				session.hostName, session.hostIP, session.hostPort);
+		}
+
+		for (size_t i = s_discoveredSessions.size(); i > 0; i--)
+		{
+			if (now - s_discoveredSessions[i - 1].lastSeenTick > 5000)
+			{
+				app.DebugPrintf("Win64 LAN: Session \"%ls\" at %s timed out\n",
+					s_discoveredSessions[i - 1].hostName, s_discoveredSessions[i - 1].hostIP);
+				s_discoveredSessions.erase(s_discoveredSessions.begin() + (i - 1));
+			}
+		}
+
+		LeaveCriticalSection(&s_discoveryLock);
+	}
+
+	return 0;
+}
+
+#endif