|buildstatus|_ |codecov|_ |nala|_

🔀 Async

Asynchronous framework in C for systems where low memory usage is important.

Features

• Delayed (asynchronous) function calls.

• Timers.

• An MQTT client (only QoS 0 is supported).

• A simple shell.

• TCP client and server.

• Secure communication with SSL/TLS.

Project homepage: https://github.com/eerimoq/async

Releases: https://github.com/eerimoq/async/releases

Examples

The hello world example, printing 'Hello world!' periodically.

.. code-block:: c

#include <stdio.h> #include "async.h"

static void on_timeout() { printf("Hello world!\n"); }

int main() { struct async_t async; struct async_timer_t timer;

   async_init(&async);
   async_set_runtime(&async, async_runtime_create());
   async_timer_init(&timer, on_timeout, NULL, 0, 1000, &async);
   async_timer_start(&timer);
   async_run_forever(&async);

   return (0);

}

There are more examples in the examples folder_.

Runtimes

A runtime implements zero or more of the following features:

• Timer handling.

• Networking (TCP).

• Call functions in the worker pool.

• Call functions from any thread.

Default

The default runtime does not implement any runtime features. It's designed for minimal dependencies and easy integration in any application.

Typical usage:

.. code-block:: c

async_init(&async); ... while (true) { epoll_wait(...); ... if (timeout) { async_tick(&async); } async_process(&async); }

Native

The native runtime implements all runtime features.

Typical usage:

.. code-block:: c

async_init(&async); async_set_runtime(&async, async_runtime_create()); ... async_run_forever(&async);

Design

Input

First *_input(self_p) is called to signal that data is available. Then read data with *_read(self_p, buf_p, size).

Output

Write data with *_write(self_p, buf_p, size).

Unit testing

Source the development environment setup script.

.. code-block:: shell

$ source setup.sh

Execute all unit tests.

.. code-block:: shell

$ make -s -j4 test ...

Execute tests matching given pattern.

.. code-block:: shell

$ make -s -j4 ARGS=core_timer test ...

.. |buildstatus| image:: https://travis-ci.org/eerimoq/async.svg?branch=master .. _buildstatus: https://travis-ci.org/eerimoq/async

.. |codecov| image:: https://codecov.io/gh/eerimoq/async/branch/master/graph/badge.svg .. _codecov: https://codecov.io/gh/eerimoq/async

.. |nala| image:: https://img.shields.io/badge/nala-test-blue.svg .. _nala: https://github.com/eerimoq/nala

.. _examples folder: https://github.com/eerimoq/async/tree/master/examples