Here's my predicament: I am using PhysFS, which allows me to treat multiple directories and archives as one virtual directory. This is for a video game in the future, which I intend to make modder-friendly. PhysFS is the best way to make it modding-friendly.
At the same time, I also intend to use a script-extender of a sort that dnyamically loads libraries and registers them in Lua. I already created a crude, makeshift, largerly proof-of-concept Lua script extender.
So what is my issue? My issue is that dlopen / LoadLibrary only works with files on a real filesystem. And I want to load via PhysFS. I load the file via PHYSFS_openRead, then use PHYSFS_read to load the file's full content into a memory buffer.
Some people suggested loading the .so / .dll file into the memory from PhysFS, and then writing it out to /tmp in Linux, or C:\temp in Windows, and then dlopen-ing it. But I don't think that's a very elegant way to do it.
So... any other ideas? I did look into mmap and thought maybe I could manually load the ELF file (on Linux) and somehow manually extract the functions, and finally register them for Lua, but so far, all I could produce was a program that gave me information about the elf.
People said that I should look into LibJIT, but I'm not exactly sure how that would help me.
So what should I do? How do I load a library into memory via PhysFS, and use an alternative to dlopen to... dlsym the functions out of it?
Please don't suggest dlopen, unless you genuinely suggest that I write out the file temporarily.
My question is largerly: how do I link? How do I get the functions out of the library which I already have in memory? And why do some people suggest LibJIT to me?