Loading binary extensions

[deliciouslytyped]

The gopher-lua repository explicitly states loadlib is not supported. Does this mean it's impossible to load shared objects as extensions, such as https://github.com/wahern/lunix ?

If this was possible, functionality not in the current Go API could be used without modifying the core application and recompiling.

Edit: are there any alternative solutions? yuin/gopher-lua#87

[zyedidia]

Yes it is impossible to load shared objects. Much of the Go stdlib is exposed by micro to Lua plugins so I think the use-case is pretty small anyway. It might in theory be possible to load shared libraries compiled from Go (or more general shared libraries), but I don't think Gopher-lua currently supports this and it would cause cross-platform difficulties.

[deliciouslytyped]

Oh hey, didn't notice you replied. In the meantime I figured out that I can at least get the additional functionality I want by exposing more things in go.lua and recompiling. Not ideal but it works.

Gopher-lua explicitly doesn't support loadlib, and to get something to work it seems one would need to make a full on FFI implementation.

Per some initial research, apparently there are ways to get a dynamic linker into Go. The more tedious part is probably doing the whole FFI thing to the C lua implementation.

[deliciouslytyped]

The point is the extensibility of micro seems a bit limited by this.
An alternative implementation of unsupporrted things could of course be to launch another process and talk to it via message passing. (So you could say, launch a second independent c based lua interpreter and do whatever you want besides directly messing with things in the micro process.)

[deliciouslytyped]

A workaround is to do something similar to #2033 , such as running and talking to a separate executable with pipes or over the network. This is useful insofar as you don't need direct access to micro's scope.

@zyedidia I don't have anything concrete in mind, but if micro had built in things for serialization to assist in the above, that would probably be helpful.

[LevitatingBusinessMan]

@deliciouslytyped You can see my solution here: https://github.com/LevitatingBusinessMan/micro-discord/blob/master/discord.lua
Though it defenitely isn't as stable as I'd like it to be.

If we could somehow have binary plugins that'd be absolutely awesome.

But like you said @deliciouslytyped, I don't think Go can dynamically call any function in a shared object.
Maybe you could have plugins that require to be compiled together with micro but you'd probably need some compiler macro and I am not sure how Go is with macro's.

[deliciouslytyped]

If you search the internet for things like "go dlopen" or "go dynamic linking" you will find answers of various stances at various times. It's "physically possible", but from what little I've seen, it doesn't look well supported. For example https://github.com/notti/nocgo is something I found.