Prevent inviting an IP address twice, which may cause some issues.

Also fixes a memory leak of unconnected connections.

src/network.zig

@@ -500,10 +500,12 @@ pub const ConnectionManager = struct {
 		}
 	}
 
-	pub fn addConnection(self: *ConnectionManager, conn: *Connection) void {
+	pub fn addConnection(self: *ConnectionManager, conn: *Connection) error{AlreadyConnected}!void {
 		self.mutex.lock();
 		defer self.mutex.unlock();
-
+		for(self.connections.items) |other| {
+			if(other.remoteAddress.ip == conn.remoteAddress.ip and other.remoteAddress.port == conn.remoteAddress.port) return error.AlreadyConnected;
+		}
 		self.connections.append(conn);
 	}
 
@@ -1324,7 +1326,7 @@ pub const Connection = struct {
 			break :blk settings.defaultPort;
 		};
 
-		result.manager.addConnection(result);
+		try result.manager.addConnection(result);
 		return result;
 	}
 

src/server/server.zig

@@ -150,14 +150,14 @@ fn init(name: []const u8) void {
 }
 
 fn deinit() void {
-	for(users.items) |user| {
-		user.decreaseRefCount();
-	}
 	users.clearAndFree();
 	for(userDeinitList.items) |user| {
 		user.deinit();
 	}
 	userDeinitList.clearAndFree();
+	for(connectionManager.connections.items) |conn| {
+		conn.user.?.decreaseRefCount();
+	}
 	connectionManager.deinit();
 	connectionManager = undefined;