coco

This library has a series of known problems and should not be used for productions. See onion for a more stable and fully tested async IO library.

A lightweight and easy to use async IO library implemented with io_uring and C++20 coroutine.

Build

This project depends on liburing. Please install liburing-devel(SUSE/RHEL based distributions) or liburing-dev(Debian based distributions) before building this project.

CMake Options

Option	Description	Default Value
COCO_BUILD_STATIC_LIBRARY	Build coco shared library. The shared target is coco::shared.	ON
COCO_BUILD_SHARED_LIBRARY	Build coco static library. The static target is coco::static.	ON
COCO_ENABLE_LTO	Enable LTO if possible.	ON
COCO_WARNINGS_AS_ERRORS	Treat warnings as errors.	OFF
COCO_BUILD_EXAMPLES	Build coco examples.	OFF

If both of the static target and shared target are build, the default target coco::coco and coco will be set to the static library.

Examples

Echo Server

See examples/echo for details.

auto echo(tcp_connection connection) noexcept -> task<void> {
    char            buffer[4096];
    size_t          bytes;
    std::error_code error;

    for (;;) {
        error = co_await connection.receive(buffer, sizeof(buffer), bytes);
        // Handle errors.
        if (bytes == 0) 
            // Connection closed.

        error = co_await connection.send(buffer, bytes, bytes);
        // Handle errors.
    }
    co_return;
}

auto acceptor(io_context &io_ctx, tcp_server server) noexcept -> task<void> {
    std::error_code error;
    tcp_connection  connection;
    for (;;) {
        error = co_await server.accept(connection);
        // Handle errors.
        io_ctx.execute(echo(std::move(connection)));
    }
}