Tiny-eventloop —— Simple Eventloop library

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This is a simple eventloop library for embedded c projects. It is designed to be simple and easy to use.

Features

• Simple and easy to use
• No dynamic memory allocation
• No dependencies
• No operating system required
• Port easily to any platform. Without asm code.
• Low memory usage
• Implement by pure C

Usage

1. Define task functions

void async_task(void *arg) {
    // do something
}

2. Add task to eventloop

// async_task will be called after 1000ms
el_setTimeout(async_task,NULL,1000);

// async_task will be called every 1000ms
el_setInterval(async_task,NULL,1000);

3. Run eventloop

el_enterLoop();

You can see more examples in examples directory.

Porting

1. Define el_tick_t

Open el_port.h and define el_tick_t to the type of your system tick. For example, if your system tick is 32bit, you can define el_tick_t as uint32_t.

typedef uint32_t el_tick_t;

2. Implement el_portTickGet

Define el_portTickGet to get system tick. System tick is the millisecond since system startup. For example, in linux, we can use gettimeofday to get system tick.

el_tick_t el_portTickGet() {
    struct timeval tv;
    gettimeofday(&tv, NULL);
    return tv.tv_sec * 1000 + tv.tv_usec / 1000;
}

Luckly, many platforms such as STM32 has a system tick counter. You can get system tick by reading the counter.

API

el_setTimeout

Run task after timeout.

void el_setTimeout(el_task_t task, void *arg, uint32_t timeout);

el_setInterval

Run task every interval.

void el_setInterval(el_task_t task, void *arg, uint32_t interval);

el_clearTimeout

Cancel timeout task.

void el_clearTimeout(el_task_t task);

el_clearInterval

Cancel interval task.

void el_clearInterval(el_task_t task);

el_enterLoop

Run eventloop.

void el_enterLoop();

License

MIT License
Author: Evan Xiao