This PR is upstreaming instances of the wasm-wave crate's traits for wasmtime values. However, we won't be able to land this PR in wasmtime until wasm-wave is written entirely in safe rust, which it presently is not, because it uses logos to derive its lexer here: https://github.com/bytecodealliance/wasm-tools/blob/main/crates/wasm-wave/src/lex.rs#L11
I hadn't looked into how logos works prior to making this PR, but when I got to the cargo vet for the logos crate, I discovered that logos derive macro generates significant amounts of unsafe rust. While I don't have any evidence logos is unsound, but it seems too risky to me to accept it into our audits, since I also have no reasonable way of ruling out that logos is unsound. In the particular case of wasm-wave, we should expect that strings accepted by the crate come from untrusted sources, so we want to be very rigorous on how they are parsed into values.
The particular bits of Lann's root wasm-wave repo this PR is upstreaming are found in https://github.com/lann/wasm-wave/tree/main/src/wasmtime. I was able to eliminate the struct FuncType definition in that code by defining component::Func::ty5918a4b tso that theComponentFunc impl of WasmType is usable.
This PR is upstreaming instances of the
wasm-wavecrate's traits for wasmtime values. However, we won't be able to land this PR in wasmtime untilwasm-waveis written entirely in safe rust, which it presently is not, because it useslogosto derive its lexer here: https://github.com/bytecodealliance/wasm-tools/blob/main/crates/wasm-wave/src/lex.rs#L11I hadn't looked into how
logosworks prior to making this PR, but when I got to thecargo vetfor thelogoscrate, I discovered that logos derive macro generates significant amounts ofunsaferust. While I don't have any evidencelogosis unsound, but it seems too risky to me to accept it into our audits, since I also have no reasonable way of ruling out thatlogosis unsound. In the particular case ofwasm-wave, we should expect that strings accepted by the crate come from untrusted sources, so we want to be very rigorous on how they are parsed into values.The particular bits of Lann's root wasm-wave repo this PR is upstreaming are found in https://github.com/lann/wasm-wave/tree/main/src/wasmtime. I was able to eliminate the
struct FuncTypedefinition in that code by definingcomponent::Func::ty5918a4b tso that theComponentFuncimpl of WasmType is usable.