`wasm-tools`

Rust tooling for low-level manipulation of WebAssembly modules

Installation

This project can be installed and compiled from source with this Cargo command:

$ cargo install wasm-tools

Additionally there are precompiled artifacts built on CI which are available for download as well.

Installation can be confirmed with:

$ wasm-tools --version

Subcommands can be explored with:

$ wasm-tools help

Tools included

The wasm-tools binary internally contains a number of subcommands for working with wasm modules. Many subcommands also come with Rust crates that can be use programmatically as well:

Tool	Crate	Description
`wasm-tools validate`	wasmparser	Validate a WebAssembly file
`wasm-tools parse`	wat and wast	Translate the WebAssembly text format to binary
`wasm-tools print`	wasmprinter	Translate the WebAssembly binary format to text
`wasm-tools smith`	wasm-smith	Generate a "random" valid WebAssembly module
`wasm-tools mutate`	wasm-mutate	Mutate an input wasm file into a new valid wasm file
`wasm-tools shrink`	wasm-shrink	Shrink a wasm file while preserving a predicate
`wasm-tools dump`		Print debugging information about the binary format
`wasm-tools objdump`		Print debugging information about section headers
`wasm-tools strip`		Remove custom sections from a WebAssembly file
`wasm-tools demangle`		Demangle Rust and C++ symbol names in the `name` section
`wasm-tools compose`	wasm-compose	Compose wasm components together
`wasm-tools component new`	wit-component	Create a component from a core wasm binary
`wasm-tools component wit`		Extract a `*.wit` interface from a component
`wasm-tools component embed`		Embed a `component-type` custom section in a core wasm binary
`wasm-tools metadata show`	wasm-metadata	Show name and producer metadata in a component or module
`wasm-tools metadata add`		Add name or producer metadata to a component or module
`wasm-tools addr2line`		Translate wasm offsets to filename/line numbers with DWARF

The wasm-tools CLI is primarily intended to be a debugging aid. The various subcommands all have --help explainer texts to describe more about their functionality as well.

Libraries

As mentioned above many of the tools of the wasm-tools CLI have libraries implemented in this repository as well. These libraries are:

wasmparser - a library to parse WebAssembly binaries
wat - a library to parse the WebAssembly text format
wast - like wat, except provides an AST
wasmprinter - prints WebAssembly binaries in their string form
wasm-mutate - a WebAssembly test case mutator
wasm-shrink - a WebAssembly test case shrinker
wasm-smith - a WebAssembly test case generator
wasm-encoder - a crate to generate a binary WebAssembly module
wit-parser - a crate to parse and manage *.wit files and interfaces.
wit-component - a crate to create components from core wasm modules.
wasm-metadata - a crate to manipulate name and producer metadata (custom sections) in a wasm module or component.

It's recommended to use the libraries directly rather than the CLI tooling when embedding into a separate project.

C/C++ bindings

Using the CMakeLists.txt in crates/c-api, wasm-tools can be used from the wasm-tools.h header.

License

This project is licensed under the Apache 2.0 license with the LLVM exception. See LICENSE for more details.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this project by you, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.

dhil / wasm-tools