1 //! Example of instantiating two modules which link to each other.
2
3 // You can execute this example with `cargo run --example linking`
4
5 use wasmtime::*;
6 use wasmtime_wasi::WasiCtx;
7
main() -> Result<()>8 fn main() -> Result<()> {
9 let engine = Engine::default();
10
11 // First set up our linker which is going to be linking modules together. We
12 // want our linker to have wasi available, so we set that up here as well.
13 let mut linker = Linker::new(&engine);
14 wasmtime_wasi::p1::add_to_linker_sync(&mut linker, |s| s)?;
15
16 // Load and compile our two modules
17 let linking1 = Module::from_file(&engine, "examples/linking1.wat")?;
18 let linking2 = Module::from_file(&engine, "examples/linking2.wat")?;
19
20 // Configure WASI and insert it into a `Store`
21 let wasi = WasiCtx::builder().inherit_stdio().inherit_args().build_p1();
22 let mut store = Store::new(&engine, wasi);
23
24 // Instantiate our first module which only uses WASI, then register that
25 // instance with the linker since the next linking will use it.
26 let linking2 = linker.instantiate(&mut store, &linking2)?;
27 linker.instance(&mut store, "linking2", linking2)?;
28
29 // And with that we can perform the final link and the execute the module.
30 let linking1 = linker.instantiate(&mut store, &linking1)?;
31 let run = linking1.get_typed_func::<(), ()>(&mut store, "run")?;
32 run.call(&mut store, ())?;
33 Ok(())
34 }
35