wasmtime-wasi: two distinct definitions of the Wasi struct, when sync vs async
//! Individual snapshots are available through
//! `wasmtime_wasi::snapshots::preview_{0, 1}::Wasi::new(&Store, Rc<RefCell<WasiCtx>>)`.
-use std::cell::RefCell;
-use std::rc::Rc;
pub use wasi_common::{Error, WasiCtx, WasiCtxBuilder, WasiDir, WasiFile};
-use wasmtime::{Config, Linker, Store};
/// Re-export the commonly used wasi-cap-std-sync crate here. This saves
/// consumers of this library from having to keep additional dependencies
@@ -18,6 +15,7 @@ use wasmtime::{Config, Linker, Store};
#[cfg(feature = "sync")]
pub mod sync {
pub use wasi_cap_std_sync::*;
+ super::define_wasi!(block_on);
}
/// Re-export the wasi-cap-std-async crate here. This saves consumers of this library from having
@@ -25,8 +23,23 @@ pub mod sync {
#[cfg(feature = "async")]
pub mod async_ {
pub use wasi_cap_std_async::*;
+ super::define_wasi!(async);
}
+// The only difference between these definitions for sync vs async is whether
+// the wasmtime::Funcs generated are async (& therefore need an async Store and an executor to run)
+// or whether they have an internal "dummy executor" that expects the implementation of all
+// the async funcs to poll to Ready immediately.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! define_wasi {
+ ($async_mode: tt) => {
+
+use std::cell::RefCell;
+use std::rc::Rc;
+use wasmtime::{Config, Linker, Store};
+use wasi_common::WasiCtx;
+
/// An instantiated instance of all available wasi exports. Presently includes
/// both the "preview1" snapshot and the "unstable" (preview0) snapshot.
pub struct Wasi {
@@ -86,7 +99,7 @@ necessary. Additionally [`Wasi::get_export`] can be used to do name-based
resolution.",
},
},
- async: { wasi_snapshot_preview1::{ poll_oneoff, sched_yield } }
+ $async_mode: { wasi_snapshot_preview1::{ poll_oneoff, sched_yield } }
});
}
pub mod preview_0 {
@@ -114,7 +127,9 @@ necessary. Additionally [`Wasi::get_export`] can be used to do name-based
resolution.",
},
},
- async: { wasi_unstable::{ poll_oneoff, sched_yield } }
+ $async_mode: { wasi_unstable::{ poll_oneoff, sched_yield } }
});
}
}
+}
+}
