版权声明:本文为博主原创文章,未经博主允许不得转载。 https://blog.csdn.net/qq_22054285/article/details/86692867
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <errno.h>
#include <sys/socket.h>
#include <netinet/in.h> /* socket类定义需要*/
#include <sys/epoll.h> /* epoll头文件 */
#include <fcntl.h> /* nonblocking需要 */
#include <sys/resource.h> /* 设置最大的连接数需要setrlimit */
#define MAXEPOLL 10000 /* 对于服务器来说,这个值可以很大的! */
#define MAXLINE 1024
#define PORT 6000
#define MAXBACK 1000
//!> 设置非阻塞
//!>
int setnonblocking( int fd )
{
if( fcntl( fd, F_SETFL, fcntl( fd, F_GETFD, 0 )|O_NONBLOCK ) == -1 )
{
printf("Set blocking error : %d\n", errno);
return -1;
}
return 0;
}
int main( int argc, char ** argv )
{
int listen_fd;
int conn_fd;
int epoll_fd;
int nread;
int cur_fds; //!> 当前已经存在的数量
int wait_fds; //!> epoll_wait 的返回值
int i;
struct sockaddr_in servaddr;
struct sockaddr_in cliaddr;
struct epoll_event ev;
struct epoll_event evs[MAXEPOLL];
struct rlimit rlt; //!> 设置连接数所需
char buf[MAXLINE];
socklen_t len = sizeof( struct sockaddr_in );
//!> 设置每个进程允许打开的最大文件数
//!> 每个主机是不一样的哦,一般服务器应该很大吧!
//!>
rlt.rlim_max = rlt.rlim_cur = MAXEPOLL;
if( setrlimit( RLIMIT_NOFILE, &rlt ) == -1 )
{
printf("Setrlimit Error : %d\n", errno);
exit( EXIT_FAILURE );
}
//!> server 套接口
//!>
bzero( &servaddr, sizeof( servaddr ) );
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = htonl( INADDR_ANY );
servaddr.sin_port = htons( PORT );
//!> 建立套接字
if( ( listen_fd = socket( AF_INET, SOCK_STREAM, 0 ) ) == -1 )
{
printf("Socket Error...\n" , errno );
exit( EXIT_FAILURE );
}
//!> 设置非阻塞模式
//!>
if( setnonblocking( listen_fd ) == -1 )
{
printf("Setnonblocking Error : %d\n", errno);
exit( EXIT_FAILURE );
}
//!> 绑定
//!>
if( bind( listen_fd, ( struct sockaddr *)&servaddr, sizeof( struct sockaddr ) ) == -1 )
{
printf("Bind Error : %d\n", errno);
exit( EXIT_FAILURE );
}
//!> 监听
//!>
if( listen( listen_fd, MAXBACK ) == -1 )
{
printf("Listen Error : %d\n", errno);
exit( EXIT_FAILURE );
}
//!> 创建epoll
//!>
epoll_fd = epoll_create( MAXEPOLL ); //!> create
ev.events = EPOLLIN | EPOLLET; //!> accept Read!
ev.data.fd = listen_fd; //!> 将listen_fd 加入
if( epoll_ctl( epoll_fd, EPOLL_CTL_ADD, listen_fd, &ev ) < 0 )
{
printf("Epoll Error : %d\n", errno);
exit( EXIT_FAILURE );
}
cur_fds = 1;
while( 1 )
{
if( ( wait_fds = epoll_wait( epoll_fd, evs, cur_fds, -1 ) ) == -1 )
{
printf( "Epoll Wait Error : %d\n", errno );
exit( EXIT_FAILURE );
}
for( i = 0; i < wait_fds; i++ )
{
if( evs[i].data.fd == listen_fd && cur_fds < MAXEPOLL )
//!> if是监听端口有事
{
if( ( conn_fd = accept( listen_fd, (struct sockaddr *)&cliaddr, &len ) ) == -1 )
{
printf("Accept Error : %d\n", errno);
exit( EXIT_FAILURE );
}
printf( "Server get from client !\n"/*, inet_ntoa(cliaddr.sin_addr), cliaddr.sin_port */);
ev.events = EPOLLIN | EPOLLET; //!> accept Read!
ev.data.fd = conn_fd; //!> 将conn_fd 加入
if( epoll_ctl( epoll_fd, EPOLL_CTL_ADD, conn_fd, &ev ) < 0 )
{
printf("Epoll Error : %d\n", errno);
exit( EXIT_FAILURE );
}
++cur_fds;
continue;
}
//!> 下面处理数据
//!>
nread = read( evs[i].data.fd, buf, sizeof( buf ) );
if( nread <= 0 ) //!> 结束后者出错
{
close( evs[i].data.fd );
epoll_ctl( epoll_fd, EPOLL_CTL_DEL, evs[i].data.fd, &ev ); //!> 删除计入的fd
--cur_fds; //!> 减少一个呗!
continue;
}
write( evs[i].data.fd, buf, nread ); //!> 回写
}
}
close( listen_fd );
return 0;
}