libevent安装

时间：2014-09-10 15:32:10 阅读：584 评论：0 收藏：0 [点我收藏+]

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libevent : 名气最大，应用最广泛，历史悠久的跨平台事件库；
libev : 较libevent而言，设计更简练，性能更好，但对Windows支持不够好；
libuv : 开发node的过程中需要一个跨平台的事件库，他们首选了libev，但又要支持Windows，故重新封装了一套，*nix下用libev实现，Windows下用IOCP实现；

win7上安装：

Libevent官网：http://libevent.org/

windows 7下编译：

编译环境： windows 7 + VS2010

（1）解压libevent到F:\libevent\libevent-2.0.21-stable

（2）打开Microsoft visual studio 2010命令行工具

（3）修改以下三个文件，添加宏定义：

在以下3个文件开头添加“#define _WIN32_WINNT 0x0500”

libevent-2.0.21-stable\event_iocp.c

libevent-2.0.21-stable\evthread_win32.c

libevent-2.0.21-stable\listener.c

（4）使用VS命令提示工具编译：

cd/d F:\libevent\libevent-2.0.21-stable

nmake /f Makefile.nmake

生成的“libevent.lib”、“libevent_core.lib”、“libevent_extras.lib”三个文件就是我们需要的 Libevent 静态链接库。

libevent_core.lib：All core event and buffer functionality. This library contains all the event_base, evbuffer, bufferevent, and utility functions.

libevent_extras.lib：This library defines protocol-specific functionality that you may or may not want for your application, including HTTP, DNS, and RPC.

libevent.lib：This library exists for historical reasons; it contains the contents of both libevent_core and libevent_extra. You shouldn’t use it; it may go away in a future version of Libevent.

VS2010下使用lib

新建一个VC++控制台项目：

环境配置：

项目下建一个Lib目录，将上面三个lib文件copy到该目录下。

新建一个Include目录，将F:\libevent\libevent-2.0.21-stable\include下的文件和文件夹copy到该目录下，F:\libevent\libevent-2.0.21-stable\WIN32-Code下的文件copy到该目录下，2个event2目录下的文件可合并一起。

main代码：

// LibeventTest.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"

#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <signal.h>

#ifndef WIN32
#include <netinet/in.h>
# ifdef _XOPEN_SOURCE_EXTENDED
#  include <arpa/inet.h>
# endif
#include <sys/socket.h>
#endif

#include "event2/bufferevent.h"
#include "event2/buffer.h"
#include "event2/listener.h"
#include "event2/util.h"
#include "event2/event.h"

#include <WinSock2.h>

static const char MESSAGE[] = "Hello, World!\n";

static const int PORT = 9995;


static void conn_writecb(struct bufferevent *bev, void *user_data)
{
    struct evbuffer *output = bufferevent_get_output(bev);
    if (evbuffer_get_length(output) == 0) 
    {
        printf("flushed answer\n");
        bufferevent_free(bev);
    }
}

static void conn_eventcb(struct bufferevent *bev, short events, void *user_data)
{
    if (events & BEV_EVENT_EOF) 
    {
        printf("Connection closed.\n");
    } 
    else if (events & BEV_EVENT_ERROR) 
    {
        printf("Got an error on the connection: %s\n",
            strerror(errno));/*XXX win32*/
    }
    /* None of the other events can happen here, since we haven‘t enabled
     * timeouts */
    bufferevent_free(bev);
}

static void signal_cb(evutil_socket_t sig, short events, void *user_data)
{
    struct event_base *base = (struct event_base *)user_data;
    struct timeval delay = { 2, 0 };

    printf("Caught an interrupt signal; exiting cleanly in two seconds.\n");

    event_base_loopexit(base, &delay);
}

static void listener_cb(struct evconnlistener *listener, evutil_socket_t fd,
    struct sockaddr *sa, int socklen, void *user_data)
{
    struct event_base *base = (struct event_base *)user_data;
    struct bufferevent *bev;

    bev = bufferevent_socket_new(base, fd, BEV_OPT_CLOSE_ON_FREE);
    if (!bev) 
    {
        fprintf(stderr, "Error constructing bufferevent!");
        event_base_loopbreak(base);
        return;
    }
    bufferevent_setcb(bev, NULL, conn_writecb, conn_eventcb, NULL);
    bufferevent_enable(bev, EV_WRITE);
    bufferevent_disable(bev, EV_READ);

    bufferevent_write(bev, MESSAGE, strlen(MESSAGE));
}

int main(int argc, char **argv)
{
    struct event_base *base;
    struct evconnlistener *listener;
    struct event *signal_event;

    struct sockaddr_in sin;

#ifdef WIN32
    WSADATA wsa_data;
    WSAStartup(0x0201, &wsa_data);
#endif

    base = event_base_new();
    if (!base) 
    {
        fprintf(stderr, "Could not initialize libevent!\n");
        return 1;
    }

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

    listener = evconnlistener_new_bind(base, listener_cb, (void *)base,
        LEV_OPT_REUSEABLE|LEV_OPT_CLOSE_ON_FREE, -1,
        (struct sockaddr*)&sin,
        sizeof(sin));

    if (!listener) 
    {
        fprintf(stderr, "Could not create a listener!\n");
        return 1;
    }

    signal_event = evsignal_new(base, SIGINT, signal_cb, (void *)base);

    if (!signal_event || event_add(signal_event, NULL)<0) 
    {
        fprintf(stderr, "Could not create/add a signal event!\n");
        return 1;
    }

    event_base_dispatch(base);

    evconnlistener_free(listener);
    event_free(signal_event);
    event_base_free(base);

    printf("done\n");
    return 0;
}