谁有用libevent在windows下做服务器的例子吗

2016-03-11 01:01:29 244 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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网上下载了个例子，发现有些问题不太明白，就是没有数据收到的时候，它那个接收数据的事件还能触发，下面是代码



#include "stdafx.h"

#include <event.h>

#include <WinSock2.h>

#pragma comment(lib, "libevent.lib")

#pragma comment(lib, "ws2_32.lib")



#define LINSTEN_PORT	3528

#define LISTEN_MAX		5

#define BUFFER_SIZE		1024

struct event_base *base = NULL;



struct sock_ev

{

	struct event *read_ev;

	struct event *write_ev;

	char *buf;

	sock_ev()

	{

		read_ev = NULL;

		write_ev = NULL;

		buf = new char[BUFFER_SIZE];

		memset(buf, 0, BUFFER_SIZE);

	}



	~sock_ev()

	{

		delete[] buf;

	}

};



void release_sock_cv(sock_ev *ev)

{

	if (ev->read_ev)

	{

		if( 0 != event_del(ev->read_ev))

		{

			printf("del err\n");

		}

		event_free(ev->read_ev);

		ev->read_ev = NULL;

	}

	if (ev->write_ev)

	{

		event_del(ev->write_ev);

		event_free(ev->write_ev);

		ev->write_ev = NULL;

	}

	free(ev);

}



void on_read(evutil_socket_t sock, short eventRead, void *arg)

{

	sock_ev *ev = (sock_ev*)arg;

	int nSize = recv(sock, (char*)ev->buf, BUFFER_SIZE, 0);

	if (nSize == SOCKET_ERROR )

	{

		printf("client socket closed\n");

		release_sock_cv(ev);

		closesocket(sock);

		return;

	}

	printf("read %s\n", ev->buf);

//	char *p = "this is Servwer!\nrecv hello world!";

//	send(sock, p, strlen(p), 0);

}



void on_write(evutil_socket_t sock, short eventWrite, void *arg)

{

	sock_ev *ev = (sock_ev*)arg;

	printf("write %s\n", ev->buf);

//	printf("on_write\n");

}



void on_accept(int sock, short eventAccept, void *arg)

{	

	struct sockaddr_in cliAddr;

	int nSize = sizeof(sockaddr_in);

	SOCKET cliSock = accept(sock, (sockaddr*)&cliAddr, &nSize);

	sock_ev *ev = new sock_ev;

	struct event *eventRead = event_new(base, cliSock, EV_READ | EV_PERSIST, on_read, ev);

	struct event *eventWrite = event_new(base, cliSock, EV_WRITE | EV_PERSIST, on_write, ev);

	ev->read_ev = eventRead;

	ev->write_ev = eventWrite;

	event_add(eventRead, NULL);

	event_add(eventWrite, NULL);

}



int _tmain(int argc, _TCHAR* argv[])

{

	WSAData wsaData;

	WSAStartup(MAKEWORD(2, 0), &wsaData);

	SOCKET sockListen = socket(AF_INET, SOCK_STREAM, 0);

	sockaddr_in srvAddr;

	srvAddr.sin_addr.s_addr = INADDR_ANY;

	srvAddr.sin_family = AF_INET;

	srvAddr.sin_port = htons(LINSTEN_PORT);



	if (bind(sockListen, (sockaddr*)&srvAddr, sizeof(sockaddr)) != 0)

	{

		printf("bind err = %d\n", WSAGetLastError());

		return 0;

	}

	if(0 !=  listen(sockListen, LISTEN_MAX))

	{

		printf("listen err = %d\n", WSAGetLastError());

		return 0;

	}



	base = event_base_new();

	struct event *eventListen = event_new(base, sockListen, EV_READ | EV_PERSIST, on_accept, NULL);

	event_add(eventListen, NULL);

	event_base_dispatch(base);	



	closesocket(sockListen);

	event_base_free(base);

	WSACleanup();

	return 0;

}