zephyr

zephy is a C++ thread-per-core library that provides asynchronous I/O primitives and synchronization tools for building high-performance network applications.

Key features:

• Asynchronous I/O with io_uring
• Futures, coroutines and observables
• Synchronization primitives like mutexes and semaphores
• TCP networking - clients, servers, streams
• Timers and async signal handling
• AF_XDP support for high speed packet processing zephyr applications center around an event loop which drives asynchronous logic:

Task<int> co_echo(std::shared_ptr<io_uring>& handle) {
  void* buf;
  TcpListener listener = TcpListener();
  TcpStream stream_ = TcpStream();

  listener.bind_socket("127.0.0.1", htons(3344));
  
  listener.listen_socket(1024);

  co_await listener.async_accept(handle, &stream_);
  
  if(posix_memalign(&buf, 1024, 1024))
    co_return 1;

  while(1) {
    int n = co_await stream_.async_recv(handle, buf, 1024);

    if (n == 0) break;

    co_await stream_.async_send(handle, buf, n);
  }

  co_return 0;
}

Build

git clone https://github.com/g-tejas/zephyr
cd zephyr
git submodule update --init

make # build zephyr.so
make example # build examples

The AF_XDP socket and BPF integration allows building high performance network functions like load balancers, firewalls, NATs etc without kernel involvement.

zephyr provides the core asynchronous infrastructure to leverage modern Linux features like io_uring, eBPF, AF_XDP for constructing fast and scalable network services in C++20.

Ideas

• Use tracy for performance handling?

Credits

• Issue in zig repository for event loop redesign
• A Programmer-Friendly I/O Abstraction Over io_uring and kqueue
• ⭐ AF_XDP in Glommio