Overview

A rust project with C++ code compatible with wasm. Uses libsodium.

Prerequisites

1. Download and install wasi-sdk from the official GitHub repository. Choose the appropriate version for your system.
2. After downloading, extract the wasi-sdk package and set up the environment variables:

export WASI_SDK_PATH=~/Downloads/wasi-sdk-22.0
export PATH=$WASI_SDK_PATH/bin:$PATH

3. You may also need to install rustup
4. Run sh prepare-sodium.sh to prepare libsodium for wasm env. You may need to install zig in advance.
5. Run sh prepare-openssl.sh to prepare libssl for wasm env. Also, in some of your C++ file you need to define pid_t getpid(void) {return 1;} since WASI lacks process identifiers, so we nede to define some stub.
6. Run sh prepare-boost.sh to prepare boost for wasm env.

Build

cargo build --target=wasm32-wasi --release

Run

wasmedge --reactor target/wasm32-wasi/release/my_rust_app.wasm test

This should print the following:

[test] Hello from Rust
[hello] Hello, World from C++! (std::cout)
[hello] Hello World from C++! (printf)
The sodium is initialized!
sodium randombytes: 714298213