Core/Guild: Fix memory leak on Guild disband

Fix memory leak when disbanding a Guild, removed from GuildMgr but never deleted. Due to the different ways of how Guild::Disband() and Guild::DeleteMember() are called, each call to these methods has a different way to delete the Guild if empty/invalid.

Valgrind log:
 2,127 (240 direct, 1,887 indirect) bytes in 1 blocks are definitely lost in loss record 54 of 81
  at operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
  by guild_commandscript::HandleGuildCreateCommand(ChatHandler*, char const*) (cs_guild.cpp:91)
  by ChatHandler::ExecuteCommandInTable(ChatCommand*, char const*, std::string const&) (Chat.cpp:339)
  by ChatHandler::ExecuteCommandInTable(ChatCommand*, char const*, std::string const&) (Chat.cpp:320)
  by ChatHandler::ParseCommands(char const*) (Chat.cpp:466)
  by WorldSession::HandleMessagechatOpcode(WorldPacket&) (ChatHandler.cpp:217)
  by WorldSession::Update(unsigned int, PacketFilter&) (WorldSession.cpp:317)
  by World::UpdateSessions(unsigned int) (World.cpp:2632)
  by World::Update(unsigned int) (World.cpp:1989)
  by WorldRunnable::run() (WorldRunnable.cpp:60)
  by ACE_Based::Thread::ThreadTask(void*) (Threading.cpp:186)
  by ACE_OS_Thread_Adapter::invoke() (in /usr/lib/libACE-6.0.3.so)

5 files changed, 17 insertions, 5 deletions

diff --git a/src/server/game/Entities/Player/Player.cpp b/src/server/game/Entities/Player/Player.cpp
index b1ee724e5f7..9bdc1ebdfc5 100644
--- a/src/server/game/Entities/Player/Player.cpp
+++ b/src/server/game/Entities/Player/Player.cpp
@@ -4713,7 +4713,7 @@ void Player::DeleteFromDB(uint64 playerguid, uint32 accountId, bool updateRealmC
 
     if (uint32 guildId = GetGuildIdFromDB(playerguid))
         if (Guild* guild = sGuildMgr->GetGuildById(guildId))
-            guild->DeleteMember(guid);
+            guild->DeleteMember(guid, false, false, true);
 
     // remove from arena teams
     LeaveAllArenaTeams(playerguid);
diff --git a/src/server/game/Guilds/Guild.cpp b/src/server/game/Guilds/Guild.cpp
index ab0f1e572f1..cc15d15fdf9 100644
--- a/src/server/game/Guilds/Guild.cpp
+++ b/src/server/game/Guilds/Guild.cpp
@@ -1578,6 +1578,8 @@ void Guild::HandleAcceptMember(WorldSession* session)
 void Guild::HandleLeaveMember(WorldSession* session)
 {
     Player* player = session->GetPlayer();
+    bool disband = false;
+
     // If leader is leaving
     if (_IsLeader(player))
     {
@@ -1585,8 +1587,11 @@ void Guild::HandleLeaveMember(WorldSession* session)
             // Leader cannot leave if he is not the last member
             SendCommandResult(session, GUILD_COMMAND_QUIT, ERR_GUILD_LEADER_LEAVE);
         else
+        {
             // Guild is disbanded if leader leaves.
             Disband();
+            disband = true;
+        }
     }
     else
     {
@@ -1599,6 +1604,9 @@ void Guild::HandleLeaveMember(WorldSession* session)
     }
 
     sCalendarMgr->RemovePlayerGuildEventsAndSignups(player->GetGUID(), GetId());
+
+    if (disband)
+        delete this;
 }
 
 void Guild::HandleRemoveMember(WorldSession* session, std::string const& name)
@@ -1812,6 +1820,7 @@ void Guild::HandleDisband(WorldSession* session)
     {
         Disband();
         TC_LOG_DEBUG(LOG_FILTER_GUILD, "Guild Successfully Disbanded");
+        delete this;
     }
 }
 
@@ -2272,7 +2281,7 @@ bool Guild::AddMember(uint64 guid, uint8 rankId)
     return true;
 }
 
-void Guild::DeleteMember(uint64 guid, bool isDisbanding, bool isKicked)
+void Guild::DeleteMember(uint64 guid, bool isDisbanding, bool isKicked, bool canDeleteGuild)
 {
     uint32 lowguid = GUID_LOPART(guid);
     Player* player = ObjectAccessor::FindPlayer(guid);
@@ -2294,6 +2303,8 @@ void Guild::DeleteMember(uint64 guid, bool isDisbanding, bool isKicked)
         if (!newLeader)
         {
             Disband();
+            if (canDeleteGuild)
+                delete this;
             return;
         }
 
diff --git a/src/server/game/Guilds/Guild.h b/src/server/game/Guilds/Guild.h
index fab39f48fca..4d8987dbbf0 100644
--- a/src/server/game/Guilds/Guild.h
+++ b/src/server/game/Guilds/Guild.h
@@ -727,7 +727,7 @@ public:
     // Members
     // Adds member to guild. If rankId == GUILD_RANK_NONE, lowest rank is assigned.
     bool AddMember(uint64 guid, uint8 rankId = GUILD_RANK_NONE);
-    void DeleteMember(uint64 guid, bool isDisbanding = false, bool isKicked = false);
+    void DeleteMember(uint64 guid, bool isDisbanding = false, bool isKicked = false, bool canDeleteGuild = false);
     bool ChangeMemberRank(uint64 guid, uint8 newRank);
 
     // Bank
diff --git a/src/server/game/Handlers/CharacterHandler.cpp b/src/server/game/Handlers/CharacterHandler.cpp
index 6a7e6c5dedd..9e1dbc133a5 100644
--- a/src/server/game/Handlers/CharacterHandler.cpp
+++ b/src/server/game/Handlers/CharacterHandler.cpp
@@ -1918,7 +1918,7 @@ void WorldSession::HandleCharFactionOrRaceChange(WorldPacket& recvData)
                 PreparedQueryResult result = CharacterDatabase.Query(stmt);
                 if (result)
                     if (Guild* guild = sGuildMgr->GetGuildById((result->Fetch()[0]).GetUInt32()))
-                        guild->DeleteMember(MAKE_NEW_GUID(lowGuid, 0, HIGHGUID_PLAYER));
+                        guild->DeleteMember(MAKE_NEW_GUID(lowGuid, 0, HIGHGUID_PLAYER), false, false, true);
             }
 
             if (!HasPermission(RBAC_PERM_TWO_SIDE_ADD_FRIEND))
diff --git a/src/server/scripts/Commands/cs_guild.cpp b/src/server/scripts/Commands/cs_guild.cpp
index 0af0da10846..040c68dbacb 100644
--- a/src/server/scripts/Commands/cs_guild.cpp
+++ b/src/server/scripts/Commands/cs_guild.cpp
@@ -118,6 +118,7 @@ public:
             return false;
 
         targetGuild->Disband();
+        delete targetGuild;
 
         return true;
     }
@@ -164,7 +165,7 @@ public:
         if (!targetGuild)
             return false;
 
-        targetGuild->DeleteMember(targetGuid, false, true);
+        targetGuild->DeleteMember(targetGuid, false, true, true);
         return true;
     }