/**
* Purge all entries from a queue.
*/
int rd_kafka_q_purge0 (rd_kafka_q_t *rkq, int do_lock) {
rd_kafka_op_t *rko, *next;
TAILQ_HEAD(, rd_kafka_op_s) tmpq = TAILQ_HEAD_INITIALIZER(tmpq);
int cnt = 0;
if (do_lock)
mtx_lock(&rkq->rkq_lock);
if (rkq->rkq_fwdq) {
cnt = rd_kafka_q_purge(rkq->rkq_fwdq);
if (do_lock)
mtx_unlock(&rkq->rkq_lock);
return cnt;
}
/* Move ops queue to tmpq to avoid lock-order issue
* by locks taken from rd_kafka_op_destroy(). */
TAILQ_MOVE(&tmpq, &rkq->rkq_q, rko_link);
/* Zero out queue */
rd_kafka_q_reset(rkq);
if (do_lock)
mtx_unlock(&rkq->rkq_lock);
/* Destroy the ops */
next = TAILQ_FIRST(&tmpq);
while ((rko = next)) {
next = TAILQ_NEXT(next, rko_link);
rd_kafka_op_destroy(rko);
cnt++;
}
return cnt;
}
/**
* Initialize a queue.
*/
void rd_kafka_q_init (rd_kafka_q_t *rkq, rd_kafka_t *rk) {
rd_kafka_q_reset(rkq);
rkq->rkq_fwdq = NULL;
rkq->rkq_refcnt = 1;
rkq->rkq_flags = RD_KAFKA_Q_F_READY;
rkq->rkq_rk = rk;
mtx_init(&rkq->rkq_lock, mtx_plain);
cnd_init(&rkq->rkq_cond);
}
/**
* Move 'cnt' entries from 'srcq' to 'dstq'.
* If 'cnt' == -1 all entries will be moved.
* Returns the number of entries moved.
*/
int rd_kafka_q_move_cnt (rd_kafka_q_t *dstq, rd_kafka_q_t *srcq,
int cnt, int do_locks) {
rd_kafka_op_t *rko;
int mcnt = 0;
if (do_locks) {
mtx_lock(&srcq->rkq_lock);
mtx_lock(&dstq->rkq_lock);
}
if (!dstq->rkq_fwdq && !srcq->rkq_fwdq) {
if (cnt > 0 && dstq->rkq_qlen == 0)
rd_kafka_q_io_event(dstq);
/* Optimization, if 'cnt' is equal/larger than all
* items of 'srcq' we can move the entire queue. */
if (cnt == -1 ||
cnt >= (int)srcq->rkq_qlen) {
rd_dassert(TAILQ_EMPTY(&srcq->rkq_q) ||
srcq->rkq_qlen > 0);
TAILQ_CONCAT(&dstq->rkq_q, &srcq->rkq_q, rko_link);
mcnt = srcq->rkq_qlen;
dstq->rkq_qlen += srcq->rkq_qlen;
dstq->rkq_qsize += srcq->rkq_qsize;
rd_kafka_q_reset(srcq);
} else {
while (mcnt < cnt &&
(rko = TAILQ_FIRST(&srcq->rkq_q))) {
TAILQ_REMOVE(&srcq->rkq_q, rko, rko_link);
TAILQ_INSERT_TAIL(&dstq->rkq_q, rko, rko_link);
srcq->rkq_qlen--;
dstq->rkq_qlen++;
srcq->rkq_qsize -= rko->rko_len;
dstq->rkq_qsize += rko->rko_len;
mcnt++;
}
}
} else
mcnt = rd_kafka_q_move_cnt(dstq->rkq_fwdq ? dstq->rkq_fwdq:dstq,
srcq->rkq_fwdq ? srcq->rkq_fwdq:srcq,
cnt, do_locks);
if (do_locks) {
mtx_unlock(&dstq->rkq_lock);
mtx_unlock(&srcq->rkq_lock);
}
return mcnt;
}
