This is a simple login server designed to support Tibia Game Server. It also serves OpenTibia XML STATUS requests, although the response may not conform to server list demands of filtering the player number by IP address. Doing so is possible but would require additional data such as idle time and IP address to be included in the online characters table, which then requires changes to the original protocol, which would break compatibility.
Even though there are no Linux specific features being used, it will currently only compile on Linux. It should be simple enough to support compiling on Windows but I don't think it would add any value, considering the querymanager will be running on Linux and that they need to be both on the same machine. The makefile is very simple and should work as long as OpenSSL's libcrypto, which is the only dependency, is installed.
make -B DEBUG=0 # rebuild in release mode
make -B DEBUG=1 # rebuild in debug mode
make clean # remove `build` directory
Similar to the game server, the login server won't boot up if it's not able to connect to the Query Manager. That said, running it is straighforward, requiring only the RSA private key tibia.pem and config.cfg files to be in the working directory. For testing purposes you could simply compile and launch the application from the shell, but if you plan to run the game server on a dedicated machine, it is recommended that it is setup as a service. There is a systemd configuration file (tibia-login.service) in the repository that may be used for that purpose. The process is very similar to the one described in the Game Server so I won't repeat myself here.