Share gameflags for 0.6/0.7 instead of hardcoding it

5cf0e5e997/datasrc/network.py (L8)
5cf0e5e997/datasrc/seven/network.py (L10)

0.6 game flags:

```python
GameFlags = ["TEAMS", "FLAGS"]
```

0.7 game flags:

```python
GameFlags = Flags("GAMEFLAG", ["TEAMS", "FLAGS", "SURVIVAL", "RACE"])
```

The 0.7 protocol extended the game flags without changing the old 0.6 flags.
So flag teams and flag flags are the same in both versions and 0.7 just
has additional flags.

The server is now sending the same m_GameFlags from the gamemode
controller to 0.6 and 0.7 connections. It clamps away the unsupported
flags for 0.6.

Before this commit the ddnet server would always send the hardcodet race
flag to 0.7 connections while ignoring what the gamemode set as a game
flag.

src/engine/shared/protocolglue.cpp

@@ -4,6 +4,16 @@
 
 #include "protocolglue.h"
 
+int GameFlags_ClampToSix(int Flags)
+{
+	int Six = 0;
+	if(Flags & GAMEFLAG_TEAMS)
+		Six |= GAMEFLAG_TEAMS;
+	if(Flags & GAMEFLAG_FLAGS)
+		Six |= GAMEFLAG_FLAGS;
+	return Six;
+}
+
 int PlayerFlags_SevenToSix(int Flags)
 {
 	int Six = 0;

src/engine/shared/protocolglue.h

@@ -1,6 +1,7 @@
 #ifndef ENGINE_SHARED_PROTOCOLGLUE_H
 #define ENGINE_SHARED_PROTOCOLGLUE_H
 
+int GameFlags_ClampToSix(int Flags);
 int PlayerFlags_SevenToSix(int Flags);
 int PlayerFlags_SixToSeven(int Flags);
 void PickupType_SevenToSix(int Type7, int &Type6, int &SubType6);

src/game/server/gamecontext.cpp

@@ -1483,26 +1483,6 @@ void CGameContext::OnClientEnter(int ClientId)
 	}
 	m_pController->OnPlayerConnect(m_apPlayers[ClientId]);
 
-	if(Server()->IsSixup(ClientId))
-	{
-		{
-			protocol7::CNetMsg_Sv_GameInfo Msg;
-			Msg.m_GameFlags = protocol7::GAMEFLAG_RACE;
-			Msg.m_MatchCurrent = 1;
-			Msg.m_MatchNum = 0;
-			Msg.m_ScoreLimit = 0;
-			Msg.m_TimeLimit = 0;
-			Server()->SendPackMsg(&Msg, MSGFLAG_VITAL | MSGFLAG_NORECORD, ClientId);
-		}
-
-		// /team is essential
-		{
-			protocol7::CNetMsg_Sv_CommandInfoRemove Msg;
-			Msg.m_pName = "team";
-			Server()->SendPackMsg(&Msg, MSGFLAG_VITAL | MSGFLAG_NORECORD, ClientId);
-		}
-	}
-
 	{
 		CNetMsg_Sv_CommandInfoGroupStart Msg;
 		Server()->SendPackMsg(&Msg, MSGFLAG_VITAL | MSGFLAG_NORECORD, ClientId);

src/game/server/gamecontroller.cpp

@@ -2,6 +2,7 @@
 /* If you are missing that file, acquire a complete release at teeworlds.com.                */
 #include <engine/shared/config.h>
 
+#include <engine/shared/protocolglue.h>
 #include <game/generated/protocol.h>
 #include <game/mapitems.h>
 #include <game/server/score.h>
@@ -397,6 +398,26 @@ void IGameController::OnPlayerConnect(CPlayer *pPlayer)
 		str_format(aBuf, sizeof(aBuf), "team_join player='%d:%s' team=%d", ClientId, Server()->ClientName(ClientId), pPlayer->GetTeam());
 		GameServer()->Console()->Print(IConsole::OUTPUT_LEVEL_DEBUG, "game", aBuf);
 	}
+
+	if(Server()->IsSixup(ClientId))
+	{
+		{
+			protocol7::CNetMsg_Sv_GameInfo Msg;
+			Msg.m_GameFlags = m_GameFlags;
+			Msg.m_MatchCurrent = 1;
+			Msg.m_MatchNum = 0;
+			Msg.m_ScoreLimit = 0;
+			Msg.m_TimeLimit = 0;
+			Server()->SendPackMsg(&Msg, MSGFLAG_VITAL | MSGFLAG_NORECORD, ClientId);
+		}
+
+		// /team is essential
+		{
+			protocol7::CNetMsg_Sv_CommandInfoRemove Msg;
+			Msg.m_pName = "team";
+			Server()->SendPackMsg(&Msg, MSGFLAG_VITAL | MSGFLAG_NORECORD, ClientId);
+		}
+	}
 }
 
 void IGameController::OnPlayerDisconnect(class CPlayer *pPlayer, const char *pReason)
@@ -553,7 +574,7 @@ void IGameController::Snap(int SnappingClient)
 	if(!pGameInfoObj)
 		return;
 
-	pGameInfoObj->m_GameFlags = m_GameFlags;
+	pGameInfoObj->m_GameFlags = GameFlags_ClampToSix(m_GameFlags);
 	pGameInfoObj->m_GameStateFlags = 0;
 	if(m_GameOverTick != -1)
 		pGameInfoObj->m_GameStateFlags |= GAMESTATEFLAG_GAMEOVER;

src/game/server/gamemodes/DDRace.cpp

@@ -18,6 +18,7 @@ CGameControllerDDRace::CGameControllerDDRace(class CGameContext *pGameServer) :
 	IGameController(pGameServer)
 {
 	m_pGameType = g_Config.m_SvTestingCommands ? TEST_TYPE_NAME : GAME_TYPE_NAME;
+	m_GameFlags = protocol7::GAMEFLAG_RACE;
 }
 
 CGameControllerDDRace::~CGameControllerDDRace() = default;