Function moduleTimerHandler

app/redis-6.2.6/src/module.c:6271–6319

This is the timer handler that is called by the main event loop. We schedule * this timer to be called when the nearest of our module timers will expire. */

/* This is the timer handler that is called by the main event loop. We schedule
 * this timer to be called when the nearest of our module timers will expire. */
int moduleTimerHandler(struct aeEventLoop *eventLoop, long long id, void *clientData) {
    UNUSED(eventLoop);
    UNUSED(id);
    UNUSED(clientData);

    /* To start let's try to fire all the timers already expired. */
    raxIterator ri;
    raxStart(&ri,Timers);
    uint64_t now = ustime();
    long long next_period = 0;
    while(1) {
        raxSeek(&ri,"^",NULL,0);
        if (!raxNext(&ri)) break;
        uint64_t expiretime;
        memcpy(&expiretime,ri.key,sizeof(expiretime));
        expiretime = ntohu64(expiretime);
        if (now >= expiretime) {
            RedisModuleTimer *timer = ri.data;
            RedisModuleCtx ctx = REDISMODULE_CTX_INIT;

            ctx.module = timer->module;
            ctx.client = moduleFreeContextReusedClient;
            selectDb(ctx.client, timer->dbid);
            timer->callback(&ctx,timer->data);
            moduleFreeContext(&ctx);
            raxRemove(Timers,(unsigned char*)ri.key,ri.key_len,NULL);
            zfree(timer);
        } else {
            /* We call ustime() again instead of using the cached 'now' so that
             * 'next_period' isn't affected by the time it took to execute
             * previous calls to 'callback.
             * We need to cast 'expiretime' so that the compiler will not treat
             * the difference as unsigned (Causing next_period to be huge) in
             * case expiretime < ustime() */
            next_period = ((long long)expiretime-ustime())/1000; /* Scale to milliseconds. */
            break;
        }
    }
    raxStop(&ri);

    /* Reschedule the next timer or cancel it. */
    if (next_period <= 0) next_period = 1;
    if (raxSize(Timers) > 0) {
        return next_period;
    } else {
        aeTimer = -1;
        return AE_NOMORE;
    }
}

/* Create a new timer that will fire after `period` milliseconds, and will call
 * the specified function using `data` as argument. The returned timer ID can be