3dd5a3cb3f
* Reimplement `wasmtime-wasi` on top of `wasmtime` This commit reimplements the `wasmtime-wasi` crate on top of the `wasmtime` API crate, instead of being placed on top of the `wasmtime-*` family of internal crates. The purpose here is to continue to exercise the API as well as avoid usage of internals wherever possible and instead use the safe API as much as possible. The `wasmtime-wasi` crate's API has been updated as part of this PR as well. The general outline of it is now: * Each module snapshot has a `WasiCtxBuilder`, `WasiCtx`, and `Wasi` type. * The `WasiCtx*` types are reexported from `wasi-common`. * The `Wasi` type is synthesized by the `wig` crate's procedural macro * The `Wasi` type exposes one constructor which takes a `Store` and a `WasiCtx`, and produces a `Wasi` * Each `Wasi` struct fields for all the exported functions in that wasi module. They're all public an they all have type `wasmtime::Func` * The `Wasi` type has a `get_export` method to fetch an struct field by name. The intention here is that we can continue to make progress on #727 by integrating WASI construction into the `Instance::new` experience, but it requires everything to be part of the same system! The main oddity required by the `wasmtime-wasi` crate is that it needs access to the caller's `memory` export, if any. This is currently done with a bit of a hack and is expected to go away once interface types are more fully baked in. * Remove now no-longer-necessary APIs from `wasmtime` * rustfmt * Rename to from_abi
This is the wasmtime-wasi crate, which implements the
WebAssembly System Interface (WASI) API in Rust.
WASI is greatly inspired by and directly derived from CloudABI. It differs in that it has aspirations to expand to a greater scope, and to better support the needs of WebAssembly engines.