# Maelstrom: Added state transition and completed protocol implementation for join/leave/kick **URL:** \ **Category:** SDL Commits\ **Created:** [November 17, 2022, 7:44am UTC](https://discourse.libsdl.org/t/maelstrom-added-state-transition-and-completed-protocol-implementation-for-join-leave-kick/40011 "2022-11-17T07:44:30Z")\ **Posts on this page:** 1\ **Page:** 1

**Author:** ![SDLPushPostBot](https://discourse.libsdl.org/user_avatar/discourse.libsdl.org/sdlpushpostbot/32/4370_2.png) [@SDLPushPostBot](https://discourse.libsdl.org/u/SDLPushPostBot)\ **Post date:** [November 17, 2022, 7:44am UTC](https://discourse.libsdl.org/t/maelstrom-added-state-transition-and-completed-protocol-implementation-for-join-leave-kick/40011/1 "2022-11-17T07:44:30Z")

[https://github.com/libsdl-org/Maelstrom/commit/9a6992d9433ca9870164b165be80b30a5c6ec9d0](https://github.com/libsdl-org/Maelstrom/commit/9a6992d9433ca9870164b165be80b30a5c6ec9d0) ```diff From 9a6992d9433ca9870164b165be80b30a5c6ec9d0 Mon Sep 17 00:00:00 2001 From: Sam Lantinga <[EMAIL REDACTED]> Date: Sun, 6 Nov 2011 11:55:11 -0500 Subject: [PATCH] Added state transition and completed protocol implementation for join/leave/kick --- netlogic/gameinfo.h | 11 +++ netlogic/lobby.cpp | 173 +++++++++++++++++++++++++++++++++++--------- netlogic/lobby.h | 10 ++- netlogic/protocol.h | 9 ++- 4 files changed, 164 insertions(+), 39 deletions(-) diff --git a/netlogic/gameinfo.h b/netlogic/gameinfo.h index bde72ab7..da505a4e 100644 --- a/netlogic/gameinfo.h +++ b/netlogic/gameinfo.h @@ -77,9 +77,20 @@ class GameInfo bool ReadFromPacket(DynamicPacket &packet); void WriteToPacket(DynamicPacket &packet); + GameInfoPlayer *GetHost() { + return GetPlayer(0); + } GameInfoPlayer *GetPlayer(int index) { return &players[index]; } + GameInfoPlayer *GetPlayerByID(Uint32 playerID) { + for (int i = 0; i < MAX_PLAYERS; ++i) { + if (players[i].playerID == playerID) { + return &players[i]; + } + } + return NULL; + } bool HasPlayer(Uint32 playerID) { for (int i = 0; i < MAX_PLAYERS; ++i) { diff --git a/netlogic/lobby.cpp b/netlogic/lobby.cpp index 42aa66b0..9d1dadb6 100644 --- a/netlogic/lobby.cpp +++ b/netlogic/lobby.cpp @@ -155,6 +155,8 @@ LobbyDialogDelegate::OnHide() } } NewGame(); + } else { + SetState(STATE_NONE); } // Shut down networking @@ -176,6 +178,8 @@ LobbyDialogDelegate::OnTick() AdvertiseGame(); } else if (m_state == STATE_LISTING) { GetGameList(); + } else if (m_state == STATE_JOINING) { + SendJoinRequest(); } else { GetGameInfo(); } @@ -204,23 +208,17 @@ LobbyDialogDelegate::SetHostOrJoin(void*, int value) return; } - if (value == HOST_GAME) { - m_state = STATE_HOSTING; - } else { - m_state = STATE_LISTING; - } m_uniqueID = rand(); - m_lastRefresh = 0; + m_game.SetLocalID(m_uniqueID); - if (m_state == STATE_HOSTING) { - m_game.SetHostInfo(m_uniqueID, prefs->GetString(PREFERENCES_HANDLE)); + if (value == HOST_GAME) { + SetState(STATE_HOSTING); + } else { + SetState(STATE_LISTING); } - m_game.SetLocalID(m_uniqueID); } else { - m_state = STATE_NONE; + SetState(STATE_NONE); } - - UpdateUI(); } void @@ -281,6 +279,38 @@ LobbyDialogDelegate::UpdateUI() } } +void +LobbyDialogDelegate::SetState(LOBBY_STATE state) +{ + // Handle any state transitions here + if (state == STATE_NONE) { + if (m_state == STATE_HOSTING) { + // Notify the players that the game is gone + for (int i = 0; i < MAX_PLAYERS; ++i) { + SendKick(i); + } + } else if (m_state == STATE_JOINING || + m_state == STATE_JOINED) { + // Notify the host that we're gone + SendLeaveRequest(); + } + } else if (state == STATE_HOSTING) { + m_game.SetHostInfo(m_uniqueID, prefs->GetString(PREFERENCES_HANDLE)); + } else if (state == STATE_LISTING) { + ClearGameList(); + } + + // Set the state + m_state = state; + + // Update the UI for the new state + UpdateUI(); + + // Send any packet requests immediately + // Comment this out to simulate initial packet loss + m_lastRefresh = 0; +} + void LobbyDialogDelegate::AdvertiseGame() { @@ -325,24 +355,56 @@ void LobbyDialogDelegate::GetGameInfo() { m_packet.StartLobbyMessage(LOBBY_REQUEST_GAME_INFO); - m_packet.address = m_game.players[0].address; + m_packet.address = m_game.GetHost()->address; SDLNet_UDP_Send(gNetFD, -1, &m_packet); } void LobbyDialogDelegate::JoinGame(GameInfo &game) +{ + m_game.CopyFrom(game); + SetState(STATE_JOINING); +} + +void +LobbyDialogDelegate::SendJoinRequest() { m_packet.StartLobbyMessage(LOBBY_REQUEST_JOIN); - m_packet.Write(game.gameID); + m_packet.Write(m_game.gameID); m_packet.Write(m_uniqueID); m_packet.Write(prefs->GetString(PREFERENCES_HANDLE)); - m_packet.address = game.players[0].address;; + m_packet.address = m_game.GetHost()->address; SDLNet_UDP_Send(gNetFD, -1, &m_packet); +} - m_game.CopyFrom(game); - m_state = STATE_JOINING; - UpdateUI(); +void +LobbyDialogDelegate::SendLeaveRequest() +{ + m_packet.StartLobbyMessage(LOBBY_REQUEST_LEAVE); + m_packet.Write(m_game.gameID); + m_packet.Write(m_uniqueID); + m_packet.address = m_game.GetHost()->address; + + SDLNet_UDP_Send(gNetFD, -1, &m_packet); +} + +void +LobbyDialogDelegate::SendKick(int index) +{ + GameInfoPlayer *player; + + player = m_game.GetPlayer(index); + if (!player->playerID || player->playerID == m_uniqueID) { + return; + } + + m_packet.StartLobbyMessage(LOBBY_KICK); + m_packet.Write(m_game.gameID); + m_packet.Write(player->playerID); + m_packet.address = player->address; + + SDLNet_UDP_Send(gNetFD, -1, &m_packet); } void @@ -408,7 +470,7 @@ LobbyDialogDelegate::ProcessPacket(DynamicPacket &packet) } else if (cmd == LOBBY_REQUEST_JOIN) { ProcessRequestJoin(packet); } else if (cmd == LOBBY_REQUEST_LEAVE) { - //ProcessRequestLeave(packet); + ProcessRequestLeave(packet); } return; @@ -421,7 +483,6 @@ LobbyDialogDelegate::ProcessPacket(DynamicPacket &packet) } return; } - } // These packets we handle in all the join states @@ -430,6 +491,8 @@ LobbyDialogDelegate::ProcessPacket(DynamicPacket &packet) //RejectPing(packet); } else if (cmd == LOBBY_GAME_INFO) { ProcessGameInfo(packet); + } else if (cmd == LOBBY_KICK) { + ProcessKick(packet); } } @@ -531,6 +594,27 @@ LobbyDialogDelegate::ProcessRequestJoin(DynamicPacket &packet) UpdateUI(); } +void +LobbyDialogDelegate::ProcessRequestLeave(DynamicPacket &packet) +{ + Uint32 gameID; + Uint32 playerID; + + if (!packet.Read(gameID) || gameID != m_game.gameID) { + return; + } + if (!packet.Read(playerID) || !m_game.HasPlayer(playerID)) { + return; + } + + // Okay, clear them from the list! + GameInfoPlayer *player = m_game.GetPlayerByID(playerID); + SDL_zero(*player); + + // Update our own UI + UpdateUI(); +} + void LobbyDialogDelegate::ProcessGameInfo(DynamicPacket &packet) { @@ -540,7 +624,19 @@ LobbyDialogDelegate::ProcessGameInfo(DynamicPacket &packet) return; } - if (m_state != STATE_LISTING) { + if (m_state == STATE_LISTING) { + // Add or update the game list + int i; + for (i = 0; i < m_gameList.length(); ++i) { + if (game.gameID == m_gameList[i].gameID) { + m_gameList[i].CopyFrom(game); + break; + } + } + if (i == m_gameList.length()) { + m_gameList.add(game); + } + } else { if (game.gameID != m_game.gameID) { // Probably an old packet... return; @@ -551,31 +647,36 @@ LobbyDialogDelegate::ProcessGameInfo(DynamicPacket &packet) if (m_state == STATE_JOINING) { if (m_game.HasPlayer(m_uniqueID)) { // We successfully joined the game - m_state = STATE_JOINED; + SetState(STATE_JOINED); } } else { if (!m_game.HasPlayer(m_uniqueID)) { // We were kicked from the game - m_state = STATE_LISTING; + SetState(STATE_LISTING); } } } - if (m_state == STATE_LISTING) { - // Add or update the game list - int i; - for (i = 0; i < m_gameList.length(); ++i) { - if (game.gameID == m_gameList[i].gameID) { - m_gameList[i].CopyFrom(game); - break; - } - } - if (i == m_gameList.length()) { - m_gameList.add(game); - } + UpdateUI(); +} + +void +LobbyDialogDelegate::ProcessKick(DynamicPacket &packet) +{ + Uint32 gameID; + Uint32 playerID; + + if (m_state != STATE_JOINING && m_state != STATE_JOINED) { + return; + } + if (!packet.Read(gameID) || gameID != m_game.gameID) { + return; + } + if (!packet.Read(playerID) || playerID != m_uniqueID) { + return; } - UpdateUI(); + SetState(STATE_LISTING); } void diff --git a/netlogic/lobby.h b/netlogic/lobby.h index 9ee95bd9..a33a5a52 100644 --- a/netlogic/lobby.h +++ b/netlogic/lobby.h @@ -62,6 +62,9 @@ class LobbyDialogDelegate : public UIDialogDelegate void GetGameList(); void GetGameInfo(); void JoinGame(GameInfo &game); + void SendJoinRequest(); + void SendLeaveRequest(); + void SendKick(int index); void ClearGameInfo(); void ClearGameList(); @@ -72,14 +75,16 @@ class LobbyDialogDelegate : public UIDialogDelegate void ProcessAnnouncePlayer(DynamicPacket &packet); void ProcessRequestGameInfo(DynamicPacket &packet); void ProcessRequestJoin(DynamicPacket &packet); + void ProcessRequestLeave(DynamicPacket &packet); void ProcessGameServerList(DynamicPacket &packet); void ProcessGameInfo(DynamicPacket &packet); + void ProcessKick(DynamicPacket &packet); protected: IPaddress m_globalServer; array m_addresses; - enum { + enum LOBBY_STATE { STATE_NONE, STATE_HOSTING, STATE_LISTING, @@ -103,6 +108,9 @@ class LobbyDialogDelegate : public UIDialogDelegate UIElement *m_gameInfoArea; UIElement *m_gameInfoPlayers[MAX_PLAYERS]; UIElement *m_playButton; + +protected: + void SetState(LOBBY_STATE state); }; #endif // _lobby_h diff --git a/netlogic/protocol.h b/netlogic/protocol.h index fc69178c..40185b26 100644 --- a/netlogic/protocol.h +++ b/netlogic/protocol.h @@ -151,7 +151,6 @@ enum LobbyProtocol { LOBBY_REQUEST_JOIN, /* Sent by the joining game - Uint32 sequence; Uint32 gameID Uint32 playerID Uint8 namelen @@ -161,7 +160,13 @@ enum LobbyProtocol { LOBBY_REQUEST_LEAVE, /* Sent by the joining game - Uint32 sequence; + Uint32 gameID + Uint32 playerID + */ + + LOBBY_KICK, + /* Sent by the hosting game + Uint32 gameID Uint32 playerID */ ```