Files

Jakub Konka 0006a2af95 Dynamically load utimensat if exists on the host (#535 )

* Dynamically load utimensat if exists on the host

This commit introduces a change to file time management for *nix based
hosts in that it firstly tries to load `utimensat` symbol, and if it
doesn't exist, then falls back to `utimes` instead. This change is
borrowing very heavily from [filetime] crate, however, it introduces a
couple of helpers and methods specific to WASI use case (or more
generally, to a use case which requires modifying times of entities
specified by a pair `(DirFD, RelativePath)` rather than the typical
file time specification based only absolute path or raw file descriptor
as is the case with [filetime] crate. The trick here is, that on kernels
which do not have `utimensat` symbol, this implementation emulates this
behaviour by a combination of `openat` and `utimes`.

This commit also is meant to address #516.

[filetime]: https://github.com/alexcrichton/filetime

* Fix symlink NOFOLLOW flag setting

* Add docs and specify UTIME_NOW/OMIT on Linux

Previously, we relied on [libc] crate for `UTIME_NOW` and `UTIME_OMIT`
constants on Linux. However, following the convention assumed in
[filetime] crate, this is now changed to directly specified by us
in our crate.

[libc]: https://github.com/rust-lang/libc
[filetime]: https://github.com/alexcrichton/filetime

* Refactor UTIME_NOW/OMIT for BSD

* Address final discussion points

2019-11-11 11:42:28 -06:00

src

Dynamically load utimensat if exists on the host (#535 )

2019-11-11 11:42:28 -06:00

tests/wasm_tests

Initial reorg.

2019-11-08 06:35:40 -08:00

WASI @ 8a968f2667

General Cargo.toml cleanup. (#529 )

2019-11-08 17:22:37 -06:00

wasi-common-cbindgen

Remove unneeded extern crate, macro_use, and tidy uses.

2019-11-08 17:55:38 -08:00

wasi-misc-tests

General Cargo.toml cleanup. (#529 )

2019-11-08 17:22:37 -06:00

wig

Remove unneeded extern crate, macro_use, and tidy uses.

2019-11-08 17:55:38 -08:00

winx

Fix a missing use bitflags::bitflags;.

2019-11-08 19:43:17 -08:00

build.rs

Use r# to escape strings which may be rust keywords.

2019-11-08 22:48:57 +01:00

Cargo.toml

General Cargo.toml cleanup. (#529 )

2019-11-08 17:22:37 -06:00

LICENSE

Initial reorg.

2019-11-08 06:35:40 -08:00

LICENSE.cloudabi-utils

Initial reorg.

2019-11-08 06:35:40 -08:00

README.md

Initial reorg.

2019-11-08 06:35:40 -08:00

README.md

wasi-common

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_recv
sock_send
sock_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.