Files
wasmtime/crates/api/tests/func.rs
Alex Crichton f63c3c814e Add a first-class way of accessing caller's exports (#1290)
* Add a first-class way of accessing caller's exports

This commit is a continuation of #1237 and updates the API of `Func` to
allow defining host functions which have easy access to a caller's
memory in particular. The new APIs look like so:

* The `Func::wrap*` family of functions was condensed into one
  `Func::wrap` function.
* The ABI layer of conversions in `WasmTy` were removed
* An optional `Caller<'_>` argument can be at the front of all
  host-defined functions now.

The old way the wasi bindings looked up memory has been removed and is
now replaced with the `Caller` type. The `Caller` type has a
`get_export` method on it which allows looking up a caller's export by
name, allowing you to get access to the caller's memory easily, and even
during instantiation.

* Add a temporary note

* Move some docs
2020-03-18 16:57:31 -05:00

395 lines
11 KiB
Rust

use anyhow::Result;
use std::rc::Rc;
use std::sync::atomic::{AtomicUsize, Ordering::SeqCst};
use wasmtime::*;
#[test]
fn func_constructors() {
let store = Store::default();
Func::wrap(&store, || {});
Func::wrap(&store, |_: i32| {});
Func::wrap(&store, |_: i32, _: i64| {});
Func::wrap(&store, |_: f32, _: f64| {});
Func::wrap(&store, || -> i32 { 0 });
Func::wrap(&store, || -> i64 { 0 });
Func::wrap(&store, || -> f32 { 0.0 });
Func::wrap(&store, || -> f64 { 0.0 });
Func::wrap(&store, || -> Result<(), Trap> { loop {} });
Func::wrap(&store, || -> Result<i32, Trap> { loop {} });
Func::wrap(&store, || -> Result<i64, Trap> { loop {} });
Func::wrap(&store, || -> Result<f32, Trap> { loop {} });
Func::wrap(&store, || -> Result<f64, Trap> { loop {} });
}
#[test]
fn dtor_runs() {
static HITS: AtomicUsize = AtomicUsize::new(0);
struct A;
impl Drop for A {
fn drop(&mut self) {
HITS.fetch_add(1, SeqCst);
}
}
let store = Store::default();
let a = A;
assert_eq!(HITS.load(SeqCst), 0);
Func::wrap(&store, move || {
drop(&a);
});
assert_eq!(HITS.load(SeqCst), 1);
}
#[test]
fn dtor_delayed() -> Result<()> {
static HITS: AtomicUsize = AtomicUsize::new(0);
struct A;
impl Drop for A {
fn drop(&mut self) {
HITS.fetch_add(1, SeqCst);
}
}
let store = Store::default();
let a = A;
let func = Func::wrap(&store, move || drop(&a));
assert_eq!(HITS.load(SeqCst), 0);
let wasm = wat::parse_str(r#"(import "" "" (func))"#)?;
let module = Module::new(&store, &wasm)?;
let instance = Instance::new(&module, &[func.into()])?;
assert_eq!(HITS.load(SeqCst), 0);
drop(instance);
assert_eq!(HITS.load(SeqCst), 1);
Ok(())
}
#[test]
fn signatures_match() {
let store = Store::default();
let f = Func::wrap(&store, || {});
assert_eq!(f.ty().params(), &[]);
assert_eq!(f.ty().results(), &[]);
let f = Func::wrap(&store, || -> i32 { loop {} });
assert_eq!(f.ty().params(), &[]);
assert_eq!(f.ty().results(), &[ValType::I32]);
let f = Func::wrap(&store, || -> i64 { loop {} });
assert_eq!(f.ty().params(), &[]);
assert_eq!(f.ty().results(), &[ValType::I64]);
let f = Func::wrap(&store, || -> f32 { loop {} });
assert_eq!(f.ty().params(), &[]);
assert_eq!(f.ty().results(), &[ValType::F32]);
let f = Func::wrap(&store, || -> f64 { loop {} });
assert_eq!(f.ty().params(), &[]);
assert_eq!(f.ty().results(), &[ValType::F64]);
let f = Func::wrap(&store, |_: f32, _: f64, _: i32, _: i64, _: i32| -> f64 {
loop {}
});
assert_eq!(
f.ty().params(),
&[
ValType::F32,
ValType::F64,
ValType::I32,
ValType::I64,
ValType::I32
]
);
assert_eq!(f.ty().results(), &[ValType::F64]);
}
#[test]
fn import_works() -> Result<()> {
static HITS: AtomicUsize = AtomicUsize::new(0);
let wasm = wat::parse_str(
r#"
(import "" "" (func))
(import "" "" (func (param i32) (result i32)))
(import "" "" (func (param i32) (param i64)))
(import "" "" (func (param i32 i64 i32 f32 f64)))
(func $foo
call 0
i32.const 0
call 1
i32.const 1
i32.add
i64.const 3
call 2
i32.const 100
i64.const 200
i32.const 300
f32.const 400
f64.const 500
call 3
)
(start $foo)
"#,
)?;
let store = Store::default();
let module = Module::new(&store, &wasm)?;
Instance::new(
&module,
&[
Func::wrap(&store, || {
assert_eq!(HITS.fetch_add(1, SeqCst), 0);
})
.into(),
Func::wrap(&store, |x: i32| -> i32 {
assert_eq!(x, 0);
assert_eq!(HITS.fetch_add(1, SeqCst), 1);
1
})
.into(),
Func::wrap(&store, |x: i32, y: i64| {
assert_eq!(x, 2);
assert_eq!(y, 3);
assert_eq!(HITS.fetch_add(1, SeqCst), 2);
})
.into(),
Func::wrap(&store, |a: i32, b: i64, c: i32, d: f32, e: f64| {
assert_eq!(a, 100);
assert_eq!(b, 200);
assert_eq!(c, 300);
assert_eq!(d, 400.0);
assert_eq!(e, 500.0);
assert_eq!(HITS.fetch_add(1, SeqCst), 3);
})
.into(),
],
)?;
Ok(())
}
#[test]
fn trap_smoke() {
let store = Store::default();
let f = Func::wrap(&store, || -> Result<(), Trap> { Err(Trap::new("test")) });
let err = f.call(&[]).unwrap_err();
assert_eq!(err.message(), "test");
}
#[test]
fn trap_import() -> Result<()> {
let wasm = wat::parse_str(
r#"
(import "" "" (func))
(start 0)
"#,
)?;
let store = Store::default();
let module = Module::new(&store, &wasm)?;
let trap = Instance::new(
&module,
&[Func::wrap(&store, || -> Result<(), Trap> { Err(Trap::new("foo")) }).into()],
)
.err()
.unwrap()
.downcast::<Trap>()?;
assert_eq!(trap.message(), "foo");
Ok(())
}
#[test]
fn get_from_wrapper() {
let store = Store::default();
let f = Func::wrap(&store, || {});
assert!(f.get0::<()>().is_ok());
assert!(f.get0::<i32>().is_err());
assert!(f.get1::<(), ()>().is_ok());
assert!(f.get1::<i32, ()>().is_err());
assert!(f.get1::<i32, i32>().is_err());
assert!(f.get2::<(), (), ()>().is_ok());
assert!(f.get2::<i32, i32, ()>().is_err());
assert!(f.get2::<i32, i32, i32>().is_err());
let f = Func::wrap(&store, || -> i32 { loop {} });
assert!(f.get0::<i32>().is_ok());
let f = Func::wrap(&store, || -> f32 { loop {} });
assert!(f.get0::<f32>().is_ok());
let f = Func::wrap(&store, || -> f64 { loop {} });
assert!(f.get0::<f64>().is_ok());
let f = Func::wrap(&store, |_: i32| {});
assert!(f.get1::<i32, ()>().is_ok());
assert!(f.get1::<i64, ()>().is_err());
assert!(f.get1::<f32, ()>().is_err());
assert!(f.get1::<f64, ()>().is_err());
let f = Func::wrap(&store, |_: i64| {});
assert!(f.get1::<i64, ()>().is_ok());
let f = Func::wrap(&store, |_: f32| {});
assert!(f.get1::<f32, ()>().is_ok());
let f = Func::wrap(&store, |_: f64| {});
assert!(f.get1::<f64, ()>().is_ok());
}
#[test]
fn get_from_signature() {
struct Foo;
impl Callable for Foo {
fn call(&self, _params: &[Val], _results: &mut [Val]) -> Result<(), Trap> {
panic!()
}
}
let store = Store::default();
let ty = FuncType::new(Box::new([]), Box::new([]));
let f = Func::new(&store, ty, Rc::new(Foo));
assert!(f.get0::<()>().is_ok());
assert!(f.get0::<i32>().is_err());
assert!(f.get1::<i32, ()>().is_err());
let ty = FuncType::new(Box::new([ValType::I32]), Box::new([ValType::F64]));
let f = Func::new(&store, ty, Rc::new(Foo));
assert!(f.get0::<()>().is_err());
assert!(f.get0::<i32>().is_err());
assert!(f.get1::<i32, ()>().is_err());
assert!(f.get1::<i32, f64>().is_ok());
}
#[test]
fn get_from_module() -> anyhow::Result<()> {
let store = Store::default();
let module = Module::new(
&store,
r#"
(module
(func (export "f0"))
(func (export "f1") (param i32))
(func (export "f2") (result i32)
i32.const 0)
)
"#,
)?;
let instance = Instance::new(&module, &[])?;
let f0 = instance.get_export("f0").unwrap().func().unwrap();
assert!(f0.get0::<()>().is_ok());
assert!(f0.get0::<i32>().is_err());
let f1 = instance.get_export("f1").unwrap().func().unwrap();
assert!(f1.get0::<()>().is_err());
assert!(f1.get1::<i32, ()>().is_ok());
assert!(f1.get1::<i32, f32>().is_err());
let f2 = instance.get_export("f2").unwrap().func().unwrap();
assert!(f2.get0::<()>().is_err());
assert!(f2.get0::<i32>().is_ok());
assert!(f2.get1::<i32, ()>().is_err());
assert!(f2.get1::<i32, f32>().is_err());
Ok(())
}
#[test]
fn call_wrapped_func() -> Result<()> {
let store = Store::default();
let f = Func::wrap(&store, |a: i32, b: i64, c: f32, d: f64| {
assert_eq!(a, 1);
assert_eq!(b, 2);
assert_eq!(c, 3.0);
assert_eq!(d, 4.0);
});
f.call(&[Val::I32(1), Val::I64(2), 3.0f32.into(), 4.0f64.into()])?;
f.get4::<i32, i64, f32, f64, ()>()?(1, 2, 3.0, 4.0)?;
let f = Func::wrap(&store, || 1i32);
let results = f.call(&[])?;
assert_eq!(results.len(), 1);
assert_eq!(results[0].unwrap_i32(), 1);
assert_eq!(f.get0::<i32>()?()?, 1);
let f = Func::wrap(&store, || 2i64);
let results = f.call(&[])?;
assert_eq!(results.len(), 1);
assert_eq!(results[0].unwrap_i64(), 2);
assert_eq!(f.get0::<i64>()?()?, 2);
let f = Func::wrap(&store, || 3.0f32);
let results = f.call(&[])?;
assert_eq!(results.len(), 1);
assert_eq!(results[0].unwrap_f32(), 3.0);
assert_eq!(f.get0::<f32>()?()?, 3.0);
let f = Func::wrap(&store, || 4.0f64);
let results = f.call(&[])?;
assert_eq!(results.len(), 1);
assert_eq!(results[0].unwrap_f64(), 4.0);
assert_eq!(f.get0::<f64>()?()?, 4.0);
Ok(())
}
#[test]
fn caller_memory() -> anyhow::Result<()> {
let store = Store::default();
let f = Func::wrap(&store, |c: Caller<'_>| {
assert!(c.get_export("x").is_none());
assert!(c.get_export("y").is_none());
assert!(c.get_export("z").is_none());
});
f.call(&[])?;
let f = Func::wrap(&store, |c: Caller<'_>| {
assert!(c.get_export("x").is_none());
});
let module = Module::new(
&store,
r#"
(module
(import "" "" (func $f))
(start $f)
)
"#,
)?;
Instance::new(&module, &[f.into()])?;
let f = Func::wrap(&store, |c: Caller<'_>| {
assert!(c.get_export("memory").is_some());
});
let module = Module::new(
&store,
r#"
(module
(import "" "" (func $f))
(memory (export "memory") 1)
(start $f)
)
"#,
)?;
Instance::new(&module, &[f.into()])?;
let f = Func::wrap(&store, |c: Caller<'_>| {
assert!(c.get_export("m").is_some());
assert!(c.get_export("f").is_none());
assert!(c.get_export("g").is_none());
assert!(c.get_export("t").is_none());
});
let module = Module::new(
&store,
r#"
(module
(import "" "" (func $f))
(memory (export "m") 1)
(func (export "f"))
(global (export "g") i32 (i32.const 0))
(table (export "t") 1 funcref)
(start $f)
)
"#,
)?;
Instance::new(&module, &[f.into()])?;
Ok(())
}