Lua Socket
From Spring
LuaSocket is a development branch of spring: (so it maybe gets never into the main branch!)
see https://github.com/spring/spring/tree/luasocket
config settings
All LuaSocket related config is readonly for LuaWidgets. They can be only changed through unitsync.
| LuaSocketEnabled = 1 | Default is 0 means, all Socket functions are disabled |
| TCPAllowConnect | allow TCP-connections to the listed hosts, for example: "springrts.com:80 springfiles.com:80" which allows luasockets to connect to springrts.com at port 80 and springfiles.com at port 80. |
| TCPAllowListen | Server TCP-sockets are allowed on this port, for example: "localhost:1234 0.0.0.0:12345" |
| UDPAllowConnect | see TCPAllowConnect |
| UDPAllowConnect | see TCPAllowListen |
example code
see https://github.com/spring/spring/blob/luasocket/cont/examples/Widgets/luasocket.lua
Notes / known issues / TODO
- for "security": disallow sending udp-packets to host:port
- only ipv4 is supported (could be solved by using unstable luasocket2: http://code.matthewwild.co.uk/luasocket2-hg/)
- dns resolving is blocking, solutions: worker thread or some lib:
- adns http://www.chiark.greenend.org.uk/~ian/adns/
- dns.c http://25thandclement.com/~william/projects/dns.c.html
- tadns http://adns.sourceforge.net/
- or a lua implementation? biggest problem would be to find the local dns-server
- most lua scripts from luasocket won't work as they are blocking! rewriting them non-blocking is required! (should be in most cases few work, as parsing stuff can be reused)
- config file should be better protected, see https://github.com/spring/spring/blob/develop/rts/System/Config/ConfigHandler.cpp#L289 + https://github.com/spring/spring/commit/948d6fb9d1c95b99b5cc7929cf3e0de0f9d6d93e maybe just locking the file is best?! see also http://springrts.com/mantis/view.php?id=2891 (private report)
documentation
- http://w3.impa.br/~diego/software/luasocket/socket.html
- http://w3.impa.br/~diego/software/luasocket/tcp.html
- http://w3.impa.br/~diego/software/luasocket/udp.html