use super::arc_wake::ArcWake;
use super::waker::waker_vtable;
use alloc::sync::Arc;
use core::marker::PhantomData;
use core::mem::ManuallyDrop;
use core::ops::Deref;
use core::task::{RawWaker, Waker};
#[derive(Debug)]
pub struct WakerRef<'a> {
waker: ManuallyDrop<Waker>,
_marker: PhantomData<&'a ()>,
}
impl<'a> WakerRef<'a> {
#[inline]
pub fn new(waker: &'a Waker) -> Self {
let waker = ManuallyDrop::new(unsafe { core::ptr::read(waker) });
Self { waker, _marker: PhantomData }
}
#[inline]
pub fn new_unowned(waker: ManuallyDrop<Waker>) -> Self {
Self { waker, _marker: PhantomData }
}
}
impl Deref for WakerRef<'_> {
type Target = Waker;
#[inline]
fn deref(&self) -> &Waker {
&self.waker
}
}
#[inline]
pub fn waker_ref<W>(wake: &Arc<W>) -> WakerRef<'_>
where
W: ArcWake,
{
let ptr = Arc::as_ptr(wake).cast::<()>();
let waker =
ManuallyDrop::new(unsafe { Waker::from_raw(RawWaker::new(ptr, waker_vtable::<W>())) });
WakerRef::new_unowned(waker)
}