44 lines
1.1 KiB
Rust
44 lines
1.1 KiB
Rust
//! Example of instantiating of the WebAssembly module and
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//! invoking its exported function.
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use failure::{format_err, Error};
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use std::fs::read;
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use wasmtime_api::*;
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fn main() -> Result<(), Error> {
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let wasm = read("examples/gcd.wasm")?;
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// Instantiate engine and store.
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let engine = HostRef::new(Engine::default());
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let store = HostRef::new(Store::new(engine));
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// Load a module.
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let module = HostRef::new(Module::new(store.clone(), &wasm)?);
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// Find index of the `gcd` export.
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let gcd_index = module
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.borrow()
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.exports()
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.iter()
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.enumerate()
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.find(|(_, export)| export.name().to_string() == "gcd")
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.unwrap()
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.0;
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// Instantiate the module.
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let instance = HostRef::new(Instance::new(store.clone(), module, &[])?);
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// Invoke `gcd` export
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let gcd = instance.borrow().exports()[gcd_index]
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.func()
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.expect("gcd")
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.clone();
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let result = gcd
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.borrow()
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.call(&[Val::from(6i32), Val::from(27i32)])
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.map_err(|e| format_err!("call error: {:?}", e))?;
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println!("{:?}", result);
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Ok(())
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}
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