/*检查超时的提案，进行重新提议*/
static void proposer_check_timeouts(evutil_socket_t fd, short event, void* arg)
{
struct evproposer* p = arg;
struct timeout_iterator* iter = proposer_timeout_iterator(p->state);
/*第一个阶段超时提案*/
prepare_req* pr;
while((pr == timeout_iterator_prepare(iter)) != NULL){ /*获取超时的提案(第一阶段)*/
paxos_log_info("Instance %d timed out.", pr->iid);
/*对超时提案重新发起提议过程*/
send_prepares(p, pr);
free(pr);
}
accept_req* ar;
while((ar = timeout_iterator_accept(iter)) != NULL){ /*获得超时提案(第二阶段)*/
paxos_log_info("Instance %d timed out.", ar->iid);
send_accepts(p, ar);
free(ar);
}
/*释放超时管理的迭代器*/
timeout_iterator_free(iter);
/*插入一个定时器*/
event_add(p->timeout_ev, &p->tv);
}
static void
try_accept(struct evproposer* p) //proposer将value等包装成accept_req包，交给evacceptor，后者将他们放入bufferevent中发送
{
accept_req* ar;
while ((ar = proposer_accept(p->state)) != NULL) { //检验是否有propose实例，如果没有，执行execute
send_accepts(p, ar);
free(ar);
}
proposer_preexecute(p);
}
static void try_accept(struct evproposer* p)
{
accept_req* ar;
while((ar = proposer_accept(p->state)) != NULL){ /*获取一个完成了第一阶段的提议，并根据其构建一个accept_reqs*/
/*发起提议的第二阶段*/
send_accepts(p, ar);
free(ar);
}
/*检查是否可以发送更多的第一阶段的提议*/
proposer_preexecute(p);
}
static void
proposer_check_timeouts(evutil_socket_t fd, short event, void *arg)
{
struct evproposer* p = arg;
struct timeout_iterator* iter = proposer_timeout_iterator(p->state);
prepare_req* pr;
while ((pr = timeout_iterator_prepare(iter)) != NULL) {
paxos_log_info("Instance %d timed out.", pr->iid);
send_prepares(p, pr);
free(pr);
}
accept_req* ar;
while ((ar = timeout_iterator_accept(iter)) != NULL) {
paxos_log_info("Instance %d timed out.", ar->iid);
send_accepts(p, ar);
free(ar);
}
timeout_iterator_free(iter);
event_add(p->timeout_ev, &p->tv); //Thus, if you want to make the event pending again, you can call event_add() on it again from inside the callback function.将超时事件重新加入
}
