Struct WaitCondition 

pub struct WaitCondition<F>
where
    F: Fn() -> bool,
{ /* private fields */ }

A named condition variable backed by a WaitQueue.

Stores a reusable condition closure alongside the queue. Multiple tasks can wait on the same WaitCondition; they are all woken when notify_all is called, and each re-checks the stored condition before returning.

Inspired by Theseus OS wait_condition crate. Wrap in an Arc to share across tasks.

Example

static FLAG: AtomicBool = AtomicBool::new(false);
static COND: WaitCondition<_> = WaitCondition::new(|| FLAG.load(Ordering::Acquire));

// Waiter task:
COND.wait();

// Notifier task:
FLAG.store(true, Ordering::Release);
COND.notify_all();

Implementations

impl<F: Fn() -> bool> WaitCondition<F>

pub fn new(condition: F) -> Self

Create a new WaitCondition with the given condition function.

pub fn wait(&self)

Block the current task until the stored condition returns true.

Returns immediately (without blocking) if the condition is already true. Spurious wakeups are impossible.

Panics

Panics if called outside of a task context.

pub fn notify_one(&self) -> bool

Wake one task waiting on this condition.

The woken task will re-check the condition before returning from wait. Returns true if a task was woken.

pub fn notify_all(&self) -> usize

Wake all tasks waiting on this condition.

Each woken task will re-check the condition independently. Returns the number of tasks that were moved back to the ready queue.