libevent_study/test_conf/test_conf.cpp


#include <iostream>
#include<event2/event.h>
#include<event2/thread.h>
#include<event2/listener.h>
 #include <string.h>
#ifdef _WIN32
	
#else
	#include <signal.h>
#endif // !_WIN32

using namespace std;

#define SPORT 5001

void listen_cb(struct evconnlistener *, evutil_socket_t, struct sockaddr *, int socklen, void *arg) {
	std::cout << "listen to be" << std::endl;
}

int main()
{
#ifdef _WIN32
	//初始化socket库
	WSADATA wsa;
	WSAStartup(MAKEWORD(2, 2), &wsa);
#else 
	if (signal(SIGPIPE, SIG_IGN) == SIG_ERR) { //忽略管道信号，发送数据给已关闭的socket，会飞掉！
		return 1;
	}
#endif

	//初始化libevent上下文
	event_config *conf = event_config_new();

	//打印支持的网络模式
	const char** methods =  event_get_supported_methods();
	cout << "supported_methods" << endl;
	for (int i = 0; methods[i] != NULL; i++) {
		cout << methods[i] << endl;
	}

	//设置特征
	//设置了EV_FEATURE_FDS 其它特征就无法设置，在windows中EV_FEATURE_FDS无效
	//event_config_require_features(conf,  EV_FEATURE_FDS);  //不支持epoll

	//设置网络模型使用select
	//event_config_avoid_method(conf, "epoll");  //linux 默认顺序为 epoll -> poll -> select
	//event_config_avoid_method(conf, "poll"); 


	//windows中支持IOCP(线程池) 要查看该项是否开启成功，可以在运行程序后打开任务管理器查看线程数量
#ifdef _WIN32
	event_config_set_flag(conf, EVENT_BASE_FLAG_STARTUP_IOCP);
	evthread_use_windows_threads();
	//设置cpu数量
	SYSTEM_INFO si;
	GetSystemInfo(&si);
	event_config_set_num_cpus_hint(conf, si.dwNumberOfProcessors);
#endif


	//初始化配置上下文
	event_base* base =  event_base_new_with_config(conf);
	

	if (!base) {
		cout << "event_base_new_with_config failed!" << endl;
		base = event_base_new();
		if (!base) {
			cerr << "event_base_new failed" << endl;
			return 0;
		}
	}
	else {
		//获取当前网络模型
		cout << "current mothed is " << event_base_get_method(base) << endl;


		//确认特征是否生效
		int f = event_base_get_features(base);
		if (f& EV_FEATURE_ET) {
			cout << "EV_FEATURE_ET  events are supported" << endl;
		}
		else {
			cout << "EV_FEATURE_ET events are not supported" << endl;
		}
		if (f& EV_FEATURE_O1) {
			cout << "EV_FEATURE_O1 events are supported" << endl;
		}
		else {
			cout << "EV_FEATURE_O1 events are not supported" << endl;
		}
		if (f& EV_FEATURE_FDS) {
			cout << "EV_FEATURE_FDS events are supported" << endl;
		}
		else {
			cout << "EV_FEATURE_FDS events are not supported" << endl;
		}
		if (f& EV_FEATURE_EARLY_CLOSE) {
			cout << "EV_FEATURE_EARLY_CLOSE events are supported" << endl;
		}
		else {
			cout << "EV_FEATURE_EARLY_CLOSE events are not supported" << endl;
		}

		cout << "event_base_new_with_config success!" << endl;


		sockaddr_in sin;
		memset(&sin, 0, sizeof(sin));
		sin.sin_family = AF_INET;
		sin.sin_port = htons(SPORT);

		evconnlistener * ev = evconnlistener_new_bind(base, //libevent上下文
			listen_cb, //接收到连接的回调函数
			base, //回调函数获取的参数(根据业务来)
			LEV_OPT_REUSEABLE | LEV_OPT_CLOSE_ON_FREE, //地址重用，evconnlistener关闭同时关闭socket
			10,  //连接队列大小，对应listen函数参数
			(sockaddr*)&sin,//绑定的地址和端口
			sizeof(sin)
		);
		event_base_dispatch(base);
		event_base_free(base);
		evconnlistener_free(ev);

		event_config_free(conf);
	}
	return 0;
}