void rd_fifoq_destroy (rd_fifoq_t *rfq) {
rd_fifoq_elm_t *rfqe;
rd_mutex_lock(&rfq->rfq_lock);
while ((rfqe = TAILQ_FIRST(&rfq->rfq_q))) {
TAILQ_REMOVE(&rfq->rfq_q, rfqe, rfqe_link);
free(rfqe);
}
rd_mutex_unlock(&rfq->rfq_lock);
}
rd_fifoq_elm_t *rd_fifoq_pop0 (rd_fifoq_t *rfq, int nowait, int timeout_ms) {
rd_fifoq_elm_t *rfqe;
/* Pop the next valid element from the FIFO. */
do {
rd_mutex_lock(&rfq->rfq_lock);
while (!(rfqe = TAILQ_FIRST(&rfq->rfq_q))) {
if (nowait) {
rd_mutex_unlock(&rfq->rfq_lock);
return NULL;
}
if (timeout_ms) {
if (rd_cond_timedwait_ms(&rfq->rfq_cond,
&rfq->rfq_lock,
timeout_ms)
== ETIMEDOUT) {
rd_mutex_unlock(&rfq->rfq_lock);
return NULL;
}
} else
rd_cond_wait(&rfq->rfq_cond, &rfq->rfq_lock);
}
assert(rfq->rfq_cnt > 0);
rfq->rfq_cnt--;
TAILQ_REMOVE(&rfq->rfq_q, rfqe, rfqe_link);
if (rfqe->rfqe_refcnt == 1) {
/* Only fifoq's refcount remains,
* this entry is no longer desired on the fifo,
* ignore and remove it. */
rd_fifoq_elm_release0(rfq, rfqe);
continue;
}
break;
} while (rfqe == NULL);
rd_fifoq_elm_release0(rfq, rfqe);
rd_mutex_unlock(&rfq->rfq_lock);
return rfqe;
}
void rd_fifoq_add0 (rd_fifoq_t *rfq, void *ptr, void **ptr_purged) {
rd_fifoq_elm_t *rfqe;
if (ptr_purged)
*ptr_purged = NULL;
assert(rfq->rfq_inited);
rfqe = malloc(sizeof(*rfqe));
rfqe->rfqe_refcnt = 2; /* one for rfq, one for caller */
rfqe->rfqe_ptr = ptr;
rd_mutex_lock(&rfq->rfq_lock);
if (rfq->rfq_max_size != 0 &&
rfq->rfq_cnt >= rfq->rfq_max_size) {
rd_fifoq_elm_t *purge;
/* Queue has reached max size, drop an entry. */
if (rfq->rfq_taildrop)
purge = TAILQ_LAST(&rfq->rfq_q, rd_fifoq_elm_head_s);
else
purge = TAILQ_FIRST(&rfq->rfq_q);
if (ptr_purged)
*ptr_purged = purge->rfqe_ptr;
rfq->rfq_cnt--;
TAILQ_REMOVE(&rfq->rfq_q, purge, rfqe_link);
if (purge->rfqe_refcnt == 1) {
/* Only fifoq's refcount remained,
* this entry is no longer desired on the fifo,
* ignore and remove it. */
rd_fifoq_elm_release0(rfq, purge);
}
}
TAILQ_INSERT_TAIL(&rfq->rfq_q, rfqe, rfqe_link);
rfq->rfq_cnt++;
rd_cond_signal(&rfq->rfq_cond);
rd_mutex_unlock(&rfq->rfq_lock);
}
void rd_fifoq_set_max_size (rd_fifoq_t *rfq, int max_size, int taildrop) {
rd_mutex_lock(&rfq->rfq_lock);
rfq->rfq_max_size = max_size;
rfq->rfq_taildrop = !!taildrop;
rd_mutex_unlock(&rfq->rfq_lock);
}