Files
wasmtime/crates/wasi-common
Dan Gohman 9a88d3d894 Replace the global-exports mechanism with a caller-vmctx mechanism. (#789)
* Replace the global-exports mechanism with a caller-vmctx mechanism.

This eliminates the global exports mechanism, and instead adds a
caller-vmctx argument to wasm functions so that WASI can obtain the
memory and other things from the caller rather than looking them up in a
global registry.

This replaces #390.

* Fixup some merge conflicts

* Rustfmt

* Ensure VMContext is aligned to 16 bytes

With the removal of `global_exports` it "just so happens" that this
isn't happening naturally any more.

* Fixup some bugs with double vmctx in wasmtime crate

* Trampoline stub needed adjusting
* Use pointer type instead of always using I64 for caller vmctx
* Don't store `ir::Signature` in `Func` since we don't know the pointer
  size at creation time.
* Skip the first 2 arguments in IR signatures since that's the two vmctx
  parameters.

* Update cranelift to 0.56.0

* Handle more merge conflicts

* Rustfmt

Co-authored-by: Alex Crichton <alex@alexcrichton.com>
2020-01-21 14:50:59 -08:00
..
2020-01-09 21:57:40 -08:00
2020-01-09 21:57:40 -08:00
2020-01-09 21:57:40 -08:00
2019-11-08 06:35:40 -08:00
2019-11-08 06:35:40 -08:00

wasi-common

A Bytecode Alliance project

A library providing a common implementation of WASI hostcalls for re-use in any WASI-enabled runtime.

Crates.io version Download docs.rs docs

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

Now, you should be able to run the integration testsuite by running cargo test on the test-programs package with test_programs feature enabled:

cargo test --features test_programs --package test-programs

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.