[Code] ZSList Global to Singleton Cleanup (#4940)

* [Code] ZSList Global to Singleton Cleanup

* Final

* Post merge fixes

---------

Co-authored-by: Chris Miles <akkadius1@gmail.com>

queryserv/queryserv.cpp

@@ -28,7 +28,6 @@ Database              database;
 std::string           WorldShortName;
 const queryservconfig *Config;
 WorldServer           *worldserver = 0;
-ZSList                zs_list;
 uint32                numzones     = 0;
 
 void CatchSignal(int sig_num)
@@ -122,7 +121,7 @@ int main()
 	server_connection->OnConnectionIdentified(
 		"Zone", [&console](std::shared_ptr<EQ::Net::ServertalkServerConnection> connection) {
 			numzones++;
-			zs_list.Add(new ZoneServer(connection, console.get()));
+			ZSList::Instance()->Add(new ZoneServer(connection, console.get()));
 
 			LogInfo(
 				"New Zone Server connection from [{}] at [{}:{}] zone_count [{}]",
@@ -137,7 +136,7 @@ int main()
 	server_connection->OnConnectionRemoved(
 		"Zone", [](std::shared_ptr<EQ::Net::ServertalkServerConnection> connection) {
 			numzones--;
-			zs_list.Remove(connection->GetUUID());
+			ZSList::Instance()->Remove(connection->GetUUID());
 
 			LogInfo(
 				"Removed Zone Server connection from [{}] total zone_count [{}]",

queryserv/worldserver.cpp

@@ -26,7 +26,6 @@
 extern WorldServer           worldserver;
 extern const queryservconfig *Config;
 extern QSDatabase            qs_database;
-extern ZSList                zs_list;
 
 WorldServer::WorldServer()
 {
@@ -80,7 +79,7 @@ void WorldServer::HandleMessage(uint16 opcode, const EQ::Net::Packet &p)
 			if (o->type == ServerReload::Type::Logs) {
 				EQEmuLogSys::Instance()->LoadLogDatabaseSettings();
 				PlayerEventLogs::Instance()->ReloadSettings();
-				zs_list.SendPlayerEventLogSettings();
+				ZSList::Instance()->SendPlayerEventLogSettings();
 			}
 
 			break;

queryserv/zonelist.h

@@ -6,9 +6,9 @@
 #include <vector>
 #include <memory>
 #include <list>
+#include "zoneserver.h"
 
 class WorldTCPConnection;
-class ZoneServer;
 
 class ZSList {
 public:
@@ -17,6 +17,12 @@ public:
 	void                                    Remove(const std::string& uuid);
 	void                                    SendPlayerEventLogSettings();
 
+	static ZSList* Instance()
+	{
+		static ZSList instance;
+		return &instance;
+	}
+
 private:
 	std::list<std::unique_ptr<ZoneServer>> zone_server_list;
 };