Crate event_listener 

Notify async tasks or threads.

This is a synchronization primitive similar to eventcounts invented by Dmitry Vyukov.

You can use this crate to turn non-blocking data structures into async or blocking data structures. See a simple mutex implementation that exposes an async and a blocking interface for acquiring locks.

Examples

Wait until another thread sets a boolean flag:

use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
use std::thread;
use std::time::Duration;
use std::usize;
use event_listener::{Event, Listener};

let flag = Arc::new(AtomicBool::new(false));
let event = Arc::new(Event::new());

// Spawn a thread that will set the flag after 1 second.
thread::spawn({
    let flag = flag.clone();
    let event = event.clone();
    move || {
        // Wait for a second.
        thread::sleep(Duration::from_secs(1));

        // Set the flag.
        flag.store(true, Ordering::SeqCst);

        // Notify all listeners that the flag has been set.
        event.notify(usize::MAX);
    }
});

// Wait until the flag is set.
loop {
    // Check the flag.
    if flag.load(Ordering::SeqCst) {
        break;
    }

    // Start listening for events.
    let mut listener = event.listen();

    // Check the flag again after creating the listener.
    if flag.load(Ordering::SeqCst) {
        break;
    }

    // Wait for a notification and continue the loop.
    listener.wait();
}

Features

• The std feature (enabled by default) enables the use of the Rust standard library. Disable it for no_std support.

• The critical-section feature enables usage of the critical-section crate to enable a more efficient implementation of event-listener for no_std platforms.

• The portable-atomic feature enables the use of the portable-atomic crate to provide atomic operations on platforms that don’t support them.

Modules

notify 🔒

The Notification trait for specifying notification.

sync 🔒

Synchronization primitive implementation.

sys 🔒

Intrusive linked list-based implementation of event-listener.

Macros

forward_impl_to_listener 🔒

Implement the Listener trait using the underlying InnerListener.

listener

Create a stack-based event listener for an Event.

Structs

Event

A synchronization primitive for notifying async tasks and threads.

EventListener

A guard waiting for a notification from an Event.

Inner 🔒

Inner state of Event.

InnerListener 🔒

Enums

RegisterResult 🔒

The result of registering a listener.

State 🔒

The state of a listener.

Task 🔒

A task that can be woken up.

TaskRef 🔒

A reference to a task.

Constants

NEVER_INSERTED_PANIC 🔒

Traits

IntoNotification

A value that can be converted into a Notification.

Listener

A handle that is listening to an Event.

Notification

A notification that can be used to notify an Event.

Functions

__test_send_and_sync 🔒