Source code
Revision control
Copy as Markdown
Other Tools
use std::cell::RefCell;
use std::task::Waker;
pub(crate) struct Defer {
deferred: RefCell<Vec<Waker>>,
}
impl Defer {
pub(crate) fn new() -> Defer {
Defer {
deferred: Default::default(),
}
}
pub(crate) fn defer(&self, waker: &Waker) {
let mut deferred = self.deferred.borrow_mut();
// If the same task adds itself a bunch of times, then only add it once.
if let Some(last) = deferred.last() {
if last.will_wake(waker) {
return;
}
}
deferred.push(waker.clone());
}
pub(crate) fn is_empty(&self) -> bool {
self.deferred.borrow().is_empty()
}
pub(crate) fn wake(&self) {
while let Some(waker) = self.deferred.borrow_mut().pop() {
waker.wake();
}
}
#[cfg(tokio_taskdump)]
pub(crate) fn take_deferred(&self) -> Vec<Waker> {
let mut deferred = self.deferred.borrow_mut();
std::mem::take(&mut *deferred)
}
}