构建

cargo wasi build

lib.rs:

wasi_binio_host 和 wasi_binio_wasm

wasi_binio_wasm 是 wasm_binio 的 WebAssembly 库。另一个库是 wasi_binio_host，它在主机中使用。wasi_binio_host 创建一个 call_stub，以便主机可以调用具有复杂数据结构参数和结果的 WebAssembly 函数。wasi_binio_wasm 准备线性内存缓冲区并导出所需的 wasm 函数，以便主机可以调用。

截至今天，wasm 函数只能接受 i32、i64、f32、f64 类型。如果您在 wasm 中有如下函数 In wasm: do_compute(point1: &Point, point2: &Point)->Rect {...}，无法直接从主机调用。借助 wasm_binio 的帮助，我们可以调用 call_stub 函数并像这样发送参数和结果

主机中的代码

let result: Rect = call_stub(&instance, &(point1, point2), "do_compute")

wasm 中的代码

#[no_mangle]
fn do_compute(ptr:i32, buffer_size: i32)->i64{
   let point_tuple : (Point, Point) = wasi_binio_wasm::wasm_deserialize(ptr, buffer_size).unwrap();
   let rect: Rect = some_how_make_a_rect_from_two_points()... /* Your own logic here */
   wasi_binio_wasm::wasm_serialize(&rect).unwrap()
}
Since wasm and wasi are under active development. Wasi will soon provide complex arguments support.
At the time you find this crate, this feature probably have already been supported natively.