f3a5186230
* Fixes CraneStation/wasmtime#440 This commit introduces a couple of changes/fixes: * it annotates `log::debug!` messages with "host" to differentiate between file descriptors stored on the WASI side (aka the wrappers) and those managed by the host (aka the wrapped) * it fixes CraneStation/wasmtime#440, i.e., incorrect passing of file descriptor to `poll_oneoff` where currently errenously we pass in the wrapper instead of the wrapped value * it adds a couple more `log::debug!` macros calls for easier future debugging * Add partial refactorting to poll_oneoff This commit lays the groundwork for more clean up to come in subsequent commits. * Finalise refactoring of `poll_oneoff` * Fix compilation error on Windows * Address majority of suggestions and refactor Co-authored-by: Marcin Mielniczuk <marmistrz.dev@zoho.eu> * Add poll_oneoff test case * Leave timeout in nanoseconds in ClockEventData Instead of converting the timeout value from nanoseconds to milliseconds in the host-independent impl, move the conversion to *nix-specific impl as the conversion is currently only warranted by the POSIX `poll` syscall. * Don't fail immediately on bad descriptor If the user specifies an invalid descriptor inside a subscription, don't fail immediately but rather generate an event with the thrown WASI error code, and continue with the remaining, potentially correct subscriptions.
wasi-common
This repo will ultimately serve as a library providing a common implementation of WASI hostcalls for re-use in any WASI (and potentially non-WASI) runtimes such as Wasmtime and Lucet.
The library is an adaption of lucet-wasi crate from the Lucet project, and it is currently based on 40ae1df git revision.
Please note that the library requires Rust compiler version at least 1.37.0.
Supported syscalls
*nix
In our *nix implementation, we currently support the entire WASI API with the exception of socket hostcalls:
sock_recvsock_sendsock_shutdown
We expect these to be implemented when network access is standardised.
We also currently do not support the proc_raise hostcall, as it is expected to
be dropped entirely from WASI.
Windows
In our Windows implementation, we currently support the minimal subset of WASI API which allows for running the very basic "Hello world!" style WASM apps. More coming shortly, so stay tuned!
Development hints
When testing the crate, you may want to enable and run full wasm32 integration testsuite. This
requires wasm32-wasi target installed which can be done as follows using rustup
rustup target add wasm32-wasi
Next initiate submodules containing the integration testsuite
git submodule update --init
Now, you should be able to run the integration testsuite by enabling the wasm_tests feature
cargo test --features wasm_tests
Third-Party Code
Significant parts of our hostcall implementations are derived from the C implementations in
cloudabi-utils. See LICENSE.cloudabi-utils for license information.