wasi2ic: WASI Polyfill Tool

wasi2ic is a command-line tool that replaces WebAssembly System Interface (WASI) specific function calls with their corresponding polyfill implementations. This allows you to run Wasm binaries compiled for wasm32-wasi on the Internet Computer.

Installation

Install wasi2ic using Cargo:

cargo install wasi2ic

Usage

Replace WASI dependencies in a Wasm file using:

wasi2ic <input-wasm-file> <output_wasm_file>

This command reads the input Wasm file, removes WASI dependencies, and reroutes WASI calls to their IC-specific implementations. Note that the polyfill implementation must be present in your Wasm binary.

To include the polyfill implementation in your Canister project, add the ic-wasi-polyfill dependency in it:

cargo add ic-wasi-polyfill

Also you will need to add the initialization call to the polyfill library, basic example featuring user memory manager:

use ic_stable_structures::{memory_manager::MemoryManager, DefaultMemoryImpl};
use std::cell::RefCell;

thread_local! {
    static MEMORY_MANAGER: RefCell<MemoryManager<DefaultMemoryImpl>> =
        RefCell::new(MemoryManager::init(DefaultMemoryImpl::default()));
}

#[ic_cdk::init]
fn init() {
    MEMORY_MANAGER.with(|m| {
        let m = m.borrow();
        ic_wasi_polyfill::init_with_memory_manager(&[0u8; 32], &[], &m, 200..210);
    });
}

For more detailed information, see our examples repository.

Related repositories

Repository	Description
ic-wasi-polyfill	Polyfill library implementing the low-level WASI calls.
stable-fs	Simple file system implementation based on the stable structures. The file system implements backend for the ic-wasi-polyfill
examples	Repository containing various examplpes of running WASI projects on the IC.