static void
proposer_handle_msg(struct evproposer* p, struct bufferevent* bev) //proposer处理各种类型的消息
{
paxos_msg msg;
struct evbuffer* in;
char buffer[PAXOS_MAX_VALUE_SIZE];
in = bufferevent_get_input(bev);
evbuffer_remove(in, &msg, sizeof(paxos_msg)); //将消息文件头从输入buffer移动到msg中
if (msg.data_size > PAXOS_MAX_VALUE_SIZE) { //消息内容过大，丢弃
evbuffer_drain(in, msg.data_size);
paxos_log_error("Discarding message of size %ld. Maximum is %d",
msg.data_size, PAXOS_MAX_VALUE_SIZE);
return;
}
evbuffer_remove(in, buffer, msg.data_size); //将消息的内容移动到buffer中
switch (msg.type) {
case prepare_acks:
proposer_handle_prepare_ack(p, (prepare_ack*)buffer);
break;
case accept_acks:
proposer_handle_accept_ack(p, (accept_ack*)buffer);
break;
case submit:
proposer_handle_client_msg(p, buffer, msg.data_size);
break;
default:
paxos_log_error("Unknow msg type %d not handled", msg.type);
return;
}
try_accept(p);
}
/*proposer处理网络消息接口*/
static void proposer_handle_msg(struct evproposer* p, struct bufferevent* bev)
{
paxos_msg msg;
struct evbuffer* in;
char* buffer = NULL;
/*解读消息头*/
in = bufferevent_get_input(bev);
evbuffer_remove(in, &msg, sizeof(paxos_msg));
/*解读消息体*/
if (msg.data_size > 0) {
buffer = malloc(msg.data_size);
evbuffer_remove(in, buffer, msg.data_size);
}
/*处理消息*/
switch (msg.type){
case prepare_acks:
proposer_handle_prepare_ack(p, (prepare_ack*)buffer);
break;
case accept_acks:
proposer_handle_accept_ack(p, (accept_ack*)buffer);
break;
case submit:
proposer_handle_client_msg(p, buffer, msg.data_size);
break;
default:
paxos_log_error("Unknow msg type %d not handled", msg.type);
return;
}
/*尝试发起提议的第二阶段,阶段性检查*/
try_accept(p);
if (buffer != NULL)
free(buffer);
}
