This commit deletes the old `snapshot_0` implementation of wasi-common,
along with the `wig` crate that was used to generate bindings for it.
This then reimplements `snapshot_0` in terms of
`wasi_snapshot_preview1`. There were very few changes between the two
snapshots:
* The `nlink` field of `FileStat` was increased from 32 to 64 bits.
* The `set` field of `whence` was reordered.
* Clock subscriptions in polling dropped their redundant userdata field.
This makes all of the syscalls relatively straightforward to simply
delegate to the next snapshot's implementation. Some trickery happens to
avoid extra cost when dealing with iovecs, but since the memory layout
of iovecs remained the same this should still work.
Now that `snapshot_0` is using wiggle we simply have a trait to
implement, and that's implemented for the same `WasiCtx` that has the
`wasi_snapshot_preview1` trait implemented for it as well. While this
theoretically means that you could share the file descriptor table
between the two snapshots that's not supported in the generated bindings
just yet. A separate `WasiCtx` will be created for each WASI module.
This makes the value of `state.reachable()` inaccurate when observing at
the tail of functions (in the post-function hook) after an ordinary
return instruction.
In some cases, it is useful to do some work at entry to or exit from a
Cranelift function translated from WebAssembly. This PR adds two
optional methods to the `FuncEnvironment` trait to do just this,
analogous to the pre/post-hooks on operators that already exist.
This PR also includes a drive-by compilation fix due to the latest
nightly wherein `.is_empty()` on a `Range` ambiguously refers to either
the `Range` impl or the `ExactSizeIterator` impl and can't resolve.
* Enhance wiggle to generate its UserErrorConverstion trait with a function that returns
a Result<abi_err, String>. This enhancement allows hostcall implementations using wiggle
to return an actionable error to the instance (the abi_err) or to terminate the instance
using the String as fatal error information.
* Enhance wiggle to generate its UserErrorConverstion trait with a function that returns
a Result<abi_err, String>. This enhancement allows hostcall implementations using wiggle
to return an actionable error to the instance (the abi_err) or to terminate the instance
using the String as fatal error information.
* Enhance the wiggle/wasmtime integration to leverage new work in ab7e9c6. Hostcall
implementations generated by wiggle now return an Result<abi_error, Trap>. As a
result, hostcalls experiencing fatal errors may trap, thereby terminating the
wasmtime instance. This enhancement has been performed for both wasi snapshot1
and wasi snapshot0.
* Update wasi-nn crate to reflect enhancement in issue #2418.
* Update wiggle test-helpers for wiggle enhancement made in issue #2418.
* Address PR feedback; omit verbose return statement.
* Address PR feedback; manually format within a proc macro.
* Address PR feedback; manually format proc macro.
* Restore return statements to wasi.rs.
* Restore return statements in funcs.rs.
* Address PR feedback; omit TODO and fix formatting.
* Ok-wrap error type in assert statement.
With the module linking proposal the field name on imports is now
optional, and only the module is required to be specified. This commit
propagates this API change to the boundary of wasmtime's API, ensuring
consumers are aware of what's optional with module linking and what
isn't. Note that it's expected that all existing users will either
update accordingly or unwrap the result since module linking is
presumably disabled.
AFAIK this isn't really necessary nowadays given the prevalence of
rustfmt, and for whatever reason the Rust plugin for vim uses this file
in lieu of all other options, meaning it doesn't pass `--edition 2018`
by default which has been causing issues as I've been working on `async`
stuff. In any case I don't think we need the file regardless, so this
commit deletes it.
