better wasi

[konsumer]

I have been working on a few projects for interacting with devices on WASI, on web:

• easywasi
• web-zen-dev

This adds things like /dev/fb0.

I think this can be leveraged a few ways, but what i really want is to give users access to full wasi (zip + virtual devices) as well as the helper-functions I use now. I would prefer if the helpers did not need to be included in cart, though, to keep size down.

I think there are a few ways to accomplish this:

• like on web: create a shared fs. expose it to cart-wasi and host (helpers) then connect them together.
• figure out how to load 2 wasms properly. Make a helper wasm that translates into lower-level file-calls. dynamic linking or wasi-sdk style may have some hints. wamr may have trouble. I think null0 could essentially be dynamic-linked to cart, and then both have fs access via wasi.

I like the 2nd approach better, but I am not sure how to do it.