Files

Andrew Brown f911855612 wiggle: copy guest slices back to shared memory (#5471 )

This change upgrades `UnsafeGuestSlice` in Wiggle to expose more
functionality to be able to use `std::ptr::copy` for writing bytes into
Wasm shared memory. Additionally, it adds a new `GuestCow` type for
delineating between Wasm memory regions that can be borrowed (non-shared
memory) or must be copied (shared memory) in order to maintain Rust
guarantees.

With these in place, it is now possible to implement the `preview1`
"read" functions for shared memory. Previously, these would panic if
attempting to copy to a shared memory. This change removes the panic and
introduces some (rather complex) logic for handling both the shared and
non-shared cases:
- if reading into a Wasm non-shared memory, Wiggle guarantees that no
  other guest pointers will touch the memory region and, in the absence
  of concurrency, a WASI function can write directly to this memory
- if reading into a Wasm shared memory, the memory region can be
  concurrently modified. At @alexcrichton's request re: Rust safety,
  this change copies all of the bytes into an intermediate buffer before
  using `std::ptr::copy` to move them into Wasm memory.

This change only applies to the `preview0` and `preview1`
implementations of `wasi-common`. Fixing up other WASI implementations
(esp. wasi-crypto) is left for later.

2023-01-03 19:51:34 +00:00

cap-std-sync

Use workspace inheritance for some more dependencies (#5349 )

2022-11-29 22:32:56 +00:00

src

wiggle: copy guest slices back to shared memory (#5471 )

2023-01-03 19:51:34 +00:00

tokio

Use workspace inheritance for some more dependencies (#5349 )

2022-11-29 22:32:56 +00:00

WASI @ 0ba0c5e2e3

Implement sock_accept

2022-01-31 16:25:11 -08:00

build.rs

Add "cargo:rerun-if-changed=build.rs" to some build.rs files.

2021-09-16 11:52:21 -07:00

Cargo.toml

Use workspace inheritance for some more dependencies (#5349 )

2022-11-29 22:32:56 +00:00

LICENSE

Initial reorg.

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

README.md

Implement the remaining socket-related WASI functions. (#4776 )

2022-08-26 11:39:51 -07:00

README.md

`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 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