rt-thread/components/drivers/src/waitqueue.c

#include <stdint.h>

#include <rthw.h>
#include <rtdevice.h>
#include <rtservice.h>

extern struct rt_thread *rt_current_thread;

void rt_wqueue_add(rt_wqueue_t *queue, struct rt_wqueue_node *node)
{
    rt_base_t level;

    level = rt_hw_interrupt_disable();
    rt_list_insert_before(queue, &(node->list));
    rt_hw_interrupt_enable(level);
}

void rt_wqueue_remove(struct rt_wqueue_node *node)
{
    rt_base_t level;

    level = rt_hw_interrupt_disable();
    rt_list_remove(&(node->list));
    rt_hw_interrupt_enable(level);
}

int __wqueue_default_wake(struct rt_wqueue_node *wait, void *key)
{
    return 0;
}

void rt_wqueue_wakeup(rt_wqueue_t *queue, void *key)
{
    rt_base_t level;
    register int need_schedule = 0;

    struct rt_list_node *node;
    struct rt_wqueue_node *entry;

    if (rt_list_isempty(queue))
        return;

    level = rt_hw_interrupt_disable();
    for (node = queue->next; node != queue; node = node->next)
    {
        entry = rt_list_entry(node, struct rt_wqueue_node, list);
        if (entry->wakeup(entry, key) == 0)
        {
            rt_thread_resume(entry->polling_thread);
            need_schedule = 1;

            rt_wqueue_remove(entry);
            break;
        }
    }
    rt_hw_interrupt_enable(level);

    if (need_schedule)
        rt_schedule();
}

int rt_wqueue_wait(rt_wqueue_t *queue, int condition, int msec)
{
    int tick;
    rt_thread_t tid = rt_current_thread;
    rt_timer_t  tmr = &(tid->thread_timer);
    struct rt_wqueue_node __wait;

    tick = rt_tick_from_millisecond(msec);

    if ((condition) || (tick == 0))
        return 0;

    __wait.polling_thread = rt_thread_self();
    __wait.key = 0;
    __wait.wakeup = __wqueue_default_wake;
    rt_list_init(&__wait.list);

    rt_wqueue_add(queue, &__wait);

    /* current context checking */
    RT_DEBUG_NOT_IN_INTERRUPT;
    rt_thread_suspend(tid);

    /* start timer */
    if (tick != RT_WAITING_FOREVER)
    {
        rt_timer_control(tmr,
                         RT_TIMER_CTRL_SET_TIME,
                         &tick);

        rt_timer_start(tmr);
    }

    rt_schedule();

    rt_wqueue_remove(&__wait);

    return 0;
}