Prevent server from starting if there's bad world linkage

src/Root.cpp

@@ -327,6 +327,17 @@ void cRoot::Start(std::unique_ptr<cSettingsRepositoryInterface> a_OverridesRepo)
 
 
 
+void cRoot::StopServer()
+{
+	m_TerminateEventRaised = true;
+	m_StopEvent.Set();
+	m_InputThreadRunFlag.clear();
+}
+
+
+
+
+
 void cRoot::LoadGlobalSettings()
 {
 	// Nothing needed yet
@@ -597,9 +608,7 @@ void cRoot::ExecuteConsoleCommand(const AString & a_Cmd, cCommandOutputCallback
 	// Some commands are built-in:
 	if (a_Cmd == "stop")
 	{
-		m_TerminateEventRaised = true;
+		StopServer();
-		m_StopEvent.Set();
-		m_InputThreadRunFlag.clear();
 		return;
 	}
 	else if (a_Cmd == "restart")

src/Root.h

@@ -57,6 +57,9 @@ public:
 
 	void Start(std::unique_ptr<cSettingsRepositoryInterface> a_OverridesRepo);
 
+	/** Stops the server, as if "/stop" was typed in the console. */
+	void StopServer();
+
 	// tolua_begin
 	cServer * GetServer(void) { return m_Server; }
 	cWorld *  GetDefaultWorld(void);
@@ -66,6 +69,7 @@ public:
 	*/
 	cWorld * GetWorld(const AString & a_WorldName, bool a_SearchForFolder = false);
 
+
 	/** Returns a pointer to a world of specified name - will search loaded worlds first, then create anew if not found
 	The dimension parameter is used to create a world with a specific dimension
 	a_OverworldName should be set for non-overworld dimensions if one wishes that world to link back to an overworld via portals

src/World.cpp

@@ -520,6 +520,40 @@ void cWorld::Start(void)
 		m_LinkedOverworldName = IniFile.GetValueSet("LinkedWorlds", "OverworldName", GetLinkedOverworldName());
 	}
 
+	// If we are linked to one or more worlds that do not exist, ask the server to stop.
+	AString BadWorlds = "";
+	cRoot * Root = cRoot::Get();
+	if (GetDimension() == dimOverworld)
+	{
+		if ((!m_LinkedNetherWorldName.empty()) && (Root->GetWorld(m_LinkedNetherWorldName) == nullptr))
+		{
+			BadWorlds = m_LinkedNetherWorldName;
+		}
+		if ((!m_LinkedEndWorldName.empty()) && (Root->GetWorld(m_LinkedEndWorldName) == nullptr))
+		{
+			if (!(BadWorlds.empty()))
+			{
+				BadWorlds += ", ";
+			}
+			BadWorlds += m_LinkedEndWorldName;
+		}
+	}
+	else
+	{
+		if ((!m_LinkedOverworldName.empty()) && (Root->GetWorld(m_LinkedOverworldName) == nullptr))
+		{
+			BadWorlds = m_LinkedOverworldName;
+		}
+	}
+	if (!BadWorlds.empty())
+	{
+		const char * WorldName = m_WorldName.c_str();
+		LOGERROR("\n######\nERROR: %s is linked to one or more invalid worlds: %s\nPlease edit %s/world.ini and fix this.\n######\n",
+			WorldName, BadWorlds.c_str(), WorldName);
+		cRoot::Get()->StopServer();
+	}
+
+
 	// Adjust the enum-backed variables into their respective bounds:
 	m_GameMode         = static_cast<eGameMode>     (Clamp<int>(GameMode,         gmSurvival, gmSpectator));
 	m_TNTShrapnelLevel = static_cast<eShrapnelLevel>(Clamp<int>(TNTShrapnelLevel, slNone,     slAll));