Lua Socket

LuaSocket is a development branch of spring:

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

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
allow rules have exactly match the host:port in script. currently its not possible to use host:port in a lua widget and use the resolved hostname for connecting (and vice versa) (simple workaround, add both as rule or use the ip only)
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)