1247f2b4ae
This commit adds a suite of `wasmtime_funcref_table_*` APIs which mirror the standard APIs but have a few differences: * More errors are returned. For example error messages are communicated through `wasmtime_error_t` and out-of-bounds vs load of null can be differentiated in the `get` API. * APIs take `wasm_func_t` instead of `wasm_ref_t`. Given the recent decision to remove subtyping from the anyref proposal it's not clear how the C API for tables will be affected, so for now these APIs are all specialized to only funcref tables. * Growth now allows access to the previous size of the table, if desired, which mirrors the `table.grow` instruction. This was originally motivated by bytecodealliance/wasmtime-go#5 where the current APIs we have for working with tables don't quite work. We don't have a great way to take an anyref constructed from a `Func` and get the `Func` back out, so for now this sidesteps those concerns while we sort out the anyref story. It's intended that once the anyref story has settled and the official C API has updated we'll likely delete these wasmtime-specific APIs or implement them as trivial wrappers around the official ones.
wasmtime
A standalone runtime for WebAssembly
A Bytecode Alliance project
Guide | Contributing | Website | Chat
Installation
The Wasmtime CLI can be installed on Linux and macOS with a small install script:
$ curl https://wasmtime.dev/install.sh -sSf | bash
Windows or otherwise interested users can download installers and binaries directly from the GitHub Releases page.
Example
If you've got the Rust compiler installed then you can take some Rust source code:
fn main() {
println!("Hello, world!");
}
and compile/run it with:
$ rustup target add wasm32-wasi
$ rustc hello.rs --target wasm32-wasi
$ wasmtime hello.wasm
Hello, world!
Features
-
Lightweight. Wasmtime is a standalone runtime for WebAssembly that scales with your needs. It fits on tiny chips as well as makes use of huge servers. Wasmtime can be embedded into almost any application too.
-
Fast. Wasmtime is built on the optimizing Cranelift code generator to quickly generate high-quality machine code at runtime.
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Configurable. Whether you need to precompile your wasm ahead of time, generate code blazingly fast with Lightbeam, or interpret it at runtime, Wasmtime has you covered for all your wasm-executing needs.
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WASI. Wasmtime supports a rich set of APIs for interacting with the host environment through the WASI standard.
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Standards Compliant. Wasmtime passes the official WebAssembly test suite, implements the official C API of wasm, and implements future proposals to WebAssembly as well. Wasmtime developers are intimately engaged with the WebAssembly standards process all along the way too.
Language Support
You can use Wasmtime from a variety of different languages through embeddings of the implementation:
- Rust - the
wasmtimecrate - C - the
wasm.h,wasi.h, andwasmtime.hheaders - Python - the
wasmtimePyPI package - .NET - the
WasmtimeNuGet package - Go - the wasmtime-go repository
Documentation
📚 Read the Wasmtime guide here! 📚
The wasmtime guide is the best starting point to learn about what Wasmtime can do for you or help answer your questions about Wasmtime. If you're curious in contributing to Wasmtime, it can also help you do that!.
It's Wasmtime.