Implement a desync handler dialog

README.md

@@ -38,6 +38,7 @@ Credits
   - Whole lot of desync fixes
 - **[ZivDero](https://github.com/ZivDero)**
   - Handicaps (difficulty & credits) support
+  - Multiplayer desync dialog
 - **[Starkku](https://github.com/Starkku)**
   - Allow customizing whether or not special house is ally to all players via spawn.ini option (#51)
 - **[RAZER](https://github.com/CnCRAZER)**

Spawner.vcxproj

@@ -19,6 +19,8 @@
     <!-- Root -->
     <ClCompile Include="src\UI\Dialogs.cpp" />
     <ClCompile Include="src\UI\Hooks.cpp" />
+    <ClCompile Include="$(ThisDir)\src\UI\DesyncDialog.cpp" />
+    <ClCompile Include="$(ThisDir)\src\UI\DesyncDialog.Hook.cpp" />
     <ResourceCompile Include="$(ThisDir)\src\version.rc" />
     <ClCompile Include="$(ThisDir)\src\Main.cpp" />
     <ClCompile Include="$(ThisDir)\src\Main.Config.cpp" />
@@ -27,6 +29,7 @@
     <!-- Ext -->
     <ClCompile Include="$(ThisDir)\src\Ext\Event\Body.cpp" />
     <ClCompile Include="$(ThisDir)\src\Ext\INIClass\Body.cpp" />
+    <ClCompile Include="$(ThisDir)\src\Ext\Session\Body.cpp" />
     <!-- CnCNetYR -->
     <ClCompile Include="$(ThisDir)\src\CnCNetYR\AppIcon.cpp" />
     <ClCompile Include="$(ThisDir)\src\CnCNetYR\Misc.cpp" />
@@ -68,6 +71,7 @@
     <ClCompile Include="$(ThisDir)\src\Utilities\Patch.cpp" />
     <!-- Dialogs -->
     <ResourceCompile Include="$(ThisDir)\src\UI\MultiplayerGameOptionsDialog.rc" />
+    <ResourceCompile Include="$(ThisDir)\src\UI\DesyncDialog.rc" />
   </ItemGroup>
   <!-- Header files -->
   <ItemGroup>
@@ -78,12 +82,16 @@
     <!-- Ext -->
     <ClInclude Include="$(ThisDir)\src\Ext\Event\Body.h" />
     <ClInclude Include="$(ThisDir)\src\Ext\INIClass\Body.h" />
+    <ClInclude Include="$(ThisDir)\src\Ext\Session\Body.h" />
     <!-- CnCNetYR -->
     <ClInclude Include="$(ThisDir)\src\CnCNetYR\Ra2Mode.h" />
     <!-- Misc -->
     <ClInclude Include="$(ThisDir)\src\UI\Dialogs.h" />
+    <ClInclude Include="$(ThisDir)\src\UI\DesyncDialog.h" />
+    <ClInclude Include="$(ThisDir)\src\UI\DesyncDialog.Resource.h" />
     <!-- Spawner -->
     <ClInclude Include="$(ThisDir)\src\Spawner\NetHack.h" />
+    <ClInclude Include="$(ThisDir)\src\Spawner\GlobalPacketExt.h" />
     <ClInclude Include="$(ThisDir)\src\Spawner\ProtocolZero.h" />
     <ClInclude Include="$(ThisDir)\src\Spawner\ProtocolZero.LatencyLevel.h" />
     <ClInclude Include="$(ThisDir)\src\Spawner\Spawner.Config.h" />

src/Ext/Session/Body.cpp

@@ -0,0 +1,181 @@
+/**
+*  yrpp-spawner
+*
+*  Copyright(C) 2022-present CnCNet
+*
+*  This program is free software: you can redistribute it and/or modify
+*  it under the terms of the GNU General Public License as published by
+*  the Free Software Foundation, either version 3 of the License, or
+*  (at your option) any later version.
+*
+*  This program is distributed in the hope that it will be useful,
+*  but WITHOUT ANY WARRANTY; without even the implied warranty of
+*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
+*  GNU General Public License for more details.
+*
+*  You should have received a copy of the GNU General Public License
+*  along with this program.If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "Body.h"
+
+#include <Spawner/GlobalPacketExt.h>
+
+#include <SessionClass.h>
+#include <HouseClass.h>
+#include <IPX.h>
+#include <IPXManagerClass.h>
+
+#include <Utilities/Macro.h>
+
+#include <cwchar>
+
+bool SessionExt::IsOutOfSync[SessionExt::MaxPlayers] = {};
+
+bool SessionExt::Is_Out_of_Sync(int house_id)
+{
+	if (house_id < 0 || house_id >= MaxPlayers)
+		return false;
+
+	return IsOutOfSync[house_id];
+}
+
+void SessionExt::Mark_Player_As_Out_of_Sync(int house_id)
+{
+	if (house_id < 0 || house_id >= MaxPlayers)
+		return;
+
+	IsOutOfSync[house_id] = true;
+}
+
+void SessionExt::Set_Master(int house_id)
+{
+	SessionClass::Instance.MasterPlayerID() = house_id;
+
+	wchar_t* const master_name = SessionClass::Instance.MasterPlayerName();
+	master_name[0] = L'\0';
+
+	if (HouseClass::Array.Count > house_id && house_id >= 0)
+	{
+		if (HouseClass* house = HouseClass::Array[house_id])
+		{
+			// MasterPlayerName is wchar_t[21]; UIName is the same width.
+			wcsncpy(master_name, house->UIName, 20);
+			master_name[20] = L'\0';
+		}
+	}
+}
+
+void SessionExt::Announce_Master()
+{
+	HouseClass* const me = HouseClass::CurrentPlayer;
+	if (me == nullptr)
+		return;
+
+	// Record ourselves as the master locally; we never receive our own packet.
+	Set_Master(me->ArrayIndex);
+
+	ExtGlobalPacketType packet {};
+	packet.Command = EXT_NET_HOST_ANNOUNCE;
+	packet.Heartbeat.HouseID = static_cast<char>(me->ArrayIndex);
+	packet.Heartbeat.IsHost = 1;
+
+	// Send to every other player. As in the engine's own beacons, index 0 is the
+	// local player, so start at 1. (Addresses come from the connections that were
+	// just created.)
+	auto& players = NodeNameType::Array;
+	for (int i = 1; i < players.Count; i++)
+	{
+		NodeNameType* const node = players[i];
+		if (node == nullptr)
+			continue;
+
+		IPXManagerClass::Instance.Send_Global_Message(
+			&packet, sizeof(packet), 1,
+			reinterpret_cast<IPXAddressClass*>(&node->Address), 0, 0);
+	}
+	IPXManagerClass::Instance.Service();
+}
+
+void SessionExt::Update_Master_After_Player_Removal()
+{
+	// Mirrors Vinifera: decide the master from the connected-players list
+	// (NodeNameType::Array == SessionClass::Players, 0xA8DA74), which
+	// Destroy_Connection shrinks immediately - even while the desync dialog has
+	// game logic suspended. We must NOT use the houses' Defeated flag here: a
+	// departed house is only flagged defeated when its queued E_REMOVEPLAYER
+	// event runs, which never happens while suspended, so the old master would
+	// keep looking valid and never get replaced. node->HouseIndex is the house
+	// id (the same value Set_Master/MasterPlayerID use).
+	const int current = SessionClass::Instance.MasterPlayerID();
+	auto& players = NodeNameType::Array;
+
+	// If the current master is still connected, there is nothing to do.
+	if (current != -1)
+	{
+		for (int i = 0; i < players.Count; i++)
+		{
+			NodeNameType* const node = players[i];
+			if (node != nullptr && node->HouseIndex == current)
+				return;
+		}
+	}
+
+	// Otherwise promote the connected player with the lowest house id. This is
+	// deterministic, so every remaining client agrees without negotiation.
+	int new_master = -1;
+	for (int i = 0; i < players.Count; i++)
+	{
+		NodeNameType* const node = players[i];
+		if (node == nullptr)
+			continue;
+
+		const int id = node->HouseIndex;
+		if (id >= 0 && (new_master == -1 || id < new_master))
+			new_master = id;
+	}
+
+	if (new_master != -1 && new_master != current)
+		Set_Master(new_master);
+}
+
+/**
+ *  Replacement for SessionClass::Am_I_Master (0x697E70).
+ *
+ *  The vanilla implementation only consults MasterPlayerID/MasterPlayerName in
+ *  GameMode::Internet (WOL) sessions, falling back to "the first non-defeated
+ *  human house is the master" otherwise. Spawner multiplayer games run as
+ *  GameMode::LAN, so the host/master we record through Set_Master (from the
+ *  EXT_NET_HOST_ANNOUNCE at game start) would be ignored. Extend the check to LAN
+ *  so the announced master is honoured - including after host migration. Mirrors
+ *  Vinifera's SessionClassExt::_Am_I_Master.
+ *
+ *  __fastcall(ECX=this, EDX unused, stack: who) reproduces the original __thiscall
+ *  (retn 4); the whole function is replaced via DEFINE_FUNCTION_JUMP below.
+ */
+static bool __fastcall SessionClass_Am_I_Master(SessionClass* pThis, void*, HouseClass* who)
+{
+	if (who == nullptr)
+		who = HouseClass::CurrentPlayer;
+
+	if ((pThis->GameMode == GameMode::Internet || pThis->GameMode == GameMode::LAN) && who != nullptr)
+	{
+		const int master = pThis->MasterPlayerID();
+		if (master != -1)
+			return who->ArrayIndex == master;
+
+		if (_wcsicmp(who->UIName, pThis->MasterPlayerName()) == 0)
+			return true;
+	}
+
+	// Fallback: the first non-defeated human house is the master.
+	for (int i = 0; i < HouseClass::Array.Count; i++)
+	{
+		HouseClass* const house = HouseClass::Array[i];
+		if (house && house->IsHumanPlayer && !house->Defeated)
+			return who == house;
+	}
+
+	return false;
+}
+DEFINE_FUNCTION_JUMP(LJMP, 0x697E70, SessionClass_Am_I_Master)

src/Ext/Session/Body.h

@@ -0,0 +1,56 @@
+/**
+*  yrpp-spawner
+*
+*  Copyright(C) 2022-present CnCNet
+*
+*  This program is free software: you can redistribute it and/or modify
+*  it under the terms of the GNU General Public License as published by
+*  the Free Software Foundation, either version 3 of the License, or
+*  (at your option) any later version.
+*
+*  This program is distributed in the hope that it will be useful,
+*  but WITHOUT ANY WARRANTY; without even the implied warranty of
+*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
+*  GNU General Public License for more details.
+*
+*  You should have received a copy of the GNU General Public License
+*  along with this program.If not, see <http://www.gnu.org/licenses/>.
+*/
+
+// Re-created bits of Vinifera's SessionClassExtension that the desync dialog
+// needs. YR's SessionClass has no equivalent of these (it only has a single
+// global OutOfSync bool and no per-player tracking), so this holds the new
+// state spawner-side. The game's native master/host fields (MasterPlayerID /
+// MasterPlayerName) DO exist and are written through here.
+
+#pragma once
+
+class HouseClass;
+
+namespace SessionExt
+{
+	// The engine supports up to 8 multiplayer houses.
+	constexpr int MaxPlayers = 8;
+
+	// --- Per-player out-of-sync tracking (the engine only has one global flag).
+	//     Set by the desync-detection hook and read by the dialog to colour each
+	//     player's status.
+	extern bool IsOutOfSync[MaxPlayers];
+
+	bool Is_Out_of_Sync(int house_id);
+	void Mark_Player_As_Out_of_Sync(int house_id);
+
+	// Assigns the game master/host, writing the engine's native MasterPlayerID
+	// and MasterPlayerName so SessionClass::Am_I_Master() agrees.
+	void Set_Master(int house_id);
+
+	// Called on the host at game start: records itself as the master and tells
+	// every other player who the host is (EXT_NET_HOST_ANNOUNCE), so MasterPlayerID
+	// is authoritative on all machines before any desync. Mirrors Vinifera's
+	// SessionClassExtension::Announce_Master.
+	void Announce_Master();
+
+	// Recomputes the master after a player has been removed: if the current
+	// master is gone, promotes the first remaining non-defeated human house.
+	void Update_Master_After_Player_Removal();
+}

src/Spawner/GlobalPacketExt.h

@@ -0,0 +1,76 @@
+/**
+*  yrpp-spawner
+*
+*  Copyright(C) 2022-present CnCNet
+*
+*  This program is free software: you can redistribute it and/or modify
+*  it under the terms of the GNU General Public License as published by
+*  the Free Software Foundation, either version 3 of the License, or
+*  (at your option) any later version.
+*
+*  This program is distributed in the hope that it will be useful,
+*  but WITHOUT ANY WARRANTY; without even the implied warranty of
+*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
+*  GNU General Public License for more details.
+*
+*  You should have received a copy of the GNU General Public License
+*  along with this program.If not, see <http://www.gnu.org/licenses/>.
+*/
+
+// New, spawner-added global network packet types.
+//
+// This mirrors Vinifera's ExtGlobalPacketType: the engine's out-of-band global
+// packet (GlobalPacketType) is 0x1C7 = 455 bytes, and the IPX layer accepts a
+// raw buffer of that size, so an alternative struct of the same size can ride
+// the very same channel. Command sits at offset 0 (matching GlobalPacketType),
+// which is what Network_Call_Back's dispatch switch reads; commands the engine
+// does not know fall through to its `default` case, which is where the receiver
+// for these is meant to be hooked in.
+
+#pragma once
+
+// Command values for the spawner's own global packets.
+//
+// The engine's native command values run up to ~0x2F. These are placed well
+// above that range so they never collide and always reach the unknown-command
+// (default) dispatch path.
+enum ExtNetCommandType : int
+{
+	EXT_NET_DESYNC_HEARTBEAT = 0xE0, // Periodic keep-alive while the desync dialog is open; also detects departures.
+	EXT_NET_DESYNC_CONTINUE  = 0xE1, // The host's decision to continue the game without the desynced players.
+	EXT_NET_DESYNC_CHAT      = 0xE2, // A chat line typed in the desync dialog while game logic is halted.
+	EXT_NET_HOST_ANNOUNCE    = 0xE3, // The host announcing itself at game start so everyone records the master.
+};
+
+#pragma pack(push, 1)
+struct ExtGlobalPacketType
+{
+	// Must alias GlobalPacketType::Command (offset 0) so the engine dispatch
+	// reads it correctly.
+	int Command;
+
+	// Sender's display name (ANSI; converted from the wide UIName on send).
+	char Name[32];
+
+	union
+	{
+		struct
+		{
+			char HouseID; // Sender's house (ArrayIndex).
+			char IsHost;  // Non-zero if the sender is the game master.
+		} Heartbeat;
+
+		struct
+		{
+			char SenderHouseID;
+			char Text[200]; // ANSI chat text.
+		} Chat;
+
+		// Forces the whole struct to the engine's GlobalPacketType size so the
+		// IPX layer treats it identically.
+		char _padding[455 - sizeof(int) - 32];
+	};
+};
+#pragma pack(pop)
+
+static_assert(sizeof(ExtGlobalPacketType) == 455, "ExtGlobalPacketType must match the engine's GlobalPacketType (0x1C7 bytes)");

src/Spawner/Spawner.Config.cpp

@@ -86,6 +86,7 @@ void SpawnerConfig::LoadFromINIFile(CCINIClass* pINI)
 		PreCalcMaxAhead  = pINI->ReadInteger(pSettingsSection, "PreCalcMaxAhead", PreCalcMaxAhead);
 		MaxLatencyLevel  = (byte)pINI->ReadInteger(pSettingsSection, "MaxLatencyLevel", (int)MaxLatencyLevel);
 		ForceMultiplayer = pINI->ReadBool(pSettingsSection, "ForceMultiplayer", ForceMultiplayer);
+		Host             = pINI->ReadBool(pSettingsSection, "Host", Host);
 	}
 
 	{ // Tunnel Options

src/Spawner/Spawner.Config.h

@@ -124,6 +124,7 @@ class SpawnerConfig
 	int PreCalcMaxAhead;
 	byte MaxLatencyLevel;
 	bool ForceMultiplayer;
+	bool Host; // True on the machine hosting the game; announces itself as the game master at start.
 
 	// Tunnel Options
 	int  TunnelId;
@@ -202,6 +203,7 @@ class SpawnerConfig
 		, PreCalcMaxAhead { 0 }
 		, MaxLatencyLevel { 0xFF }
 		, ForceMultiplayer { false }
+		, Host { false }
 
 		// Tunnel Options
 		, TunnelId { 0 }