ec5d8016f7
On Windows, `metadata` computes only partial metadata results, which don't include what WASI needs for the `inode` field in `readdir` results. cap-std has a `full_metadata` function which is able to include this extra information, however it has more strict access requirements, so it sometimes fails even when plain `metadata` would succeed. Make WASI's `readdir` silently skip over files that can't be accessed by `full_metadata`. These files wouldn't be openable in any other way by WASI programs, so the only benefit of listing them would be to let applications know that they exist. This allows it to avoid failing and avoid returning bogus results. This is part of a fix for bytecodealliance/cap-std#169.
wasi-common
A Bytecode Alliance project
A library providing a common implementation of WASI hostcalls for re-use in any WASI-enabled runtime.
The wasi-common crate 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
Now, you should be able to run the integration testsuite by running cargo test on the
test-programs package with test-programs/test_programs feature enabled:
cargo test --features test-programs/test_programs --package test-programs