#![deny(private_intra_doc_links)]
#![deny(missing_docs)]
-#![deny(unsafe_code)]
+#![cfg_attr(not(feature = "futures"), deny(unsafe_code))]
#![cfg_attr(docsrs, feature(doc_auto_cfg))]
#[cfg(feature = "std")]
use std::time::Instant;
-#[cfg(feature = "futures")]
-use futures_util::{select_biased, future::FutureExt, task};
#[cfg(not(feature = "std"))]
use alloc::vec::Vec;
} }
}
+#[cfg(feature = "futures")]
+pub(crate) mod futures_util {
+ use core::future::Future;
+ use core::task::{Poll, Waker, RawWaker, RawWakerVTable};
+ use core::pin::Pin;
+ use core::marker::Unpin;
+ pub(crate) struct Selector<A: Future<Output=()> + Unpin, B: Future<Output=bool> + Unpin> {
+ pub a: A,
+ pub b: B,
+ }
+ pub(crate) enum SelectorOutput {
+ A, B(bool),
+ }
+
+ impl<A: Future<Output=()> + Unpin, B: Future<Output=bool> + Unpin> Future for Selector<A, B> {
+ type Output = SelectorOutput;
+ fn poll(mut self: Pin<&mut Self>, ctx: &mut core::task::Context<'_>) -> Poll<SelectorOutput> {
+ match Pin::new(&mut self.a).poll(ctx) {
+ Poll::Ready(()) => { return Poll::Ready(SelectorOutput::A); },
+ Poll::Pending => {},
+ }
+ match Pin::new(&mut self.b).poll(ctx) {
+ Poll::Ready(res) => { return Poll::Ready(SelectorOutput::B(res)); },
+ Poll::Pending => {},
+ }
+ Poll::Pending
+ }
+ }
+
+ // If we want to poll a future without an async context to figure out if it has completed or
+ // not without awaiting, we need a Waker, which needs a vtable...we fill it with dummy values
+ // but sadly there's a good bit of boilerplate here.
+ fn dummy_waker_clone(_: *const ()) -> RawWaker { RawWaker::new(core::ptr::null(), &DUMMY_WAKER_VTABLE) }
+ fn dummy_waker_action(_: *const ()) { }
+
+ const DUMMY_WAKER_VTABLE: RawWakerVTable = RawWakerVTable::new(
+ dummy_waker_clone, dummy_waker_action, dummy_waker_action, dummy_waker_action);
+ pub(crate) fn dummy_waker() -> Waker { unsafe { Waker::from_raw(RawWaker::new(core::ptr::null(), &DUMMY_WAKER_VTABLE)) } }
+}
+#[cfg(feature = "futures")]
+use futures_util::{Selector, SelectorOutput, dummy_waker};
+#[cfg(feature = "futures")]
+use core::task;
+
/// Processes background events in a future.
///
/// `sleeper` should return a future which completes in the given amount of time and returns a
chain_monitor, chain_monitor.process_pending_events_async(async_event_handler).await,
channel_manager, channel_manager.process_pending_events_async(async_event_handler).await,
gossip_sync, peer_manager, logger, scorer, should_break, {
- select_biased! {
- _ = channel_manager.get_persistable_update_future().fuse() => true,
- exit = sleeper(Duration::from_millis(100)).fuse() => {
+ let fut = Selector {
+ a: channel_manager.get_persistable_update_future(),
+ b: sleeper(Duration::from_millis(100)),
+ };
+ match fut.await {
+ SelectorOutput::A => true,
+ SelectorOutput::B(exit) => {
should_break = exit;
false
}
}
}, |t| sleeper(Duration::from_secs(t)),
|fut: &mut SleepFuture, _| {
- let mut waker = task::noop_waker();
+ let mut waker = dummy_waker();
let mut ctx = task::Context::from_waker(&mut waker);
core::pin::Pin::new(fut).poll(&mut ctx).is_ready()
})