Sentinel-IO

Sentinel-IO is an asynchronous runtime written in Rust for building I/O-backed applications. It provides its own executor, task scheduler, async networking primitives, and a procedural macro for bootstrapping async programs.

Features

🚀 Executor & Scheduler	A custom single-threaded, round-robin task scheduler powering spawn() and block_on(), with JoinHandle<T> to await spawned tasks.
🌐 Async Networking	TcpListener and TcpStream with async accept, read and write, plus split() to turn a stream into an independent reader and writer.
⏱️ Timers	A Timer future for delaying execution without blocking the runtime.
🔌 Async I/O Traits	AsyncRead and AsyncWrite, implemented for the provided networking types.
✨ #[sentinel::main]	A procedural macro that turns async fn main() into a runnable entry point.

Example

use sentinel_io as sentinel;
use sentinel::io::{AsyncRead, AsyncWrite};
use sentinel::net::{TcpListener, TcpStream};
use std::net::SocketAddr;

const SERVER_ADDR: &str = "127.0.0.1:8000";

async fn handle_connection(mut conn: TcpStream, addr: SocketAddr) {
    let mut buffer = [0u8; 1024];

    loop {
        let n = conn.read(&mut buffer).await.unwrap();
        if n == 0 {
            return;
        }
        let _ = conn.write(&buffer[0..n]).await;
    }
}

#[sentinel::main]
async fn main() {
    let mut server = TcpListener::bind(SERVER_ADDR).unwrap();

    loop {
        let (client, addr) = server.accept().await.unwrap();
        sentinel::spawn(handle_connection(client, addr));
    }
}

More examples are available in the examples/ directory.

Roadmap

The following objectives are still pending:

• I/O Driver (event-driven I/O multiplexing via epoll/kqueue, replacing busy-polling)
• Multi-threading executor
• Async file I/O
• Timeout support for I/O operations
• UDP support
• Improved error handling
• Improve cargo docs

License

This project is licensed under the MIT License.