一个简短的epoll服务器示例, 监听5000个端口, 使用线程池

文章地址：
http://www.cublog.cn/u/17999/showart.php?id=159057
运行这个程序需要预先设置栈内存和文件描述符上限, 否则运行失败
ulimit -n 16384
ulimit -s 4096

文件名:server.c
编译: gcc server.c -Wall -O2 -pthread -o server
程序源码如下(请自行编辑宏定义SERVER_IP为自己的IP):

cpp 代码

/*Linux 2.6 x86_64 only*/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>

#include <sys/epoll.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <netdb.h>
#include <pthread.h>

#define THREAD_MAX 4096
#define LISTEN_MAX 5000
#define SERVER_IP "192.168.1.103"

typedef struct {
   char    ip4[128];
   int    port;
   int    fd;
} LISTEN_INFO;

//服务器参数
static LISTEN_INFO s_listens[LISTEN_MAX];

//线程池参数
static unsigned int s_thread_para[THREAD_MAX][8];//线程参数
static pthread_t s_tid[THREAD_MAX];//线程ID
pthread_mutex_t s_mutex[THREAD_MAX];//线程锁


//私有函数
static int init_thread_pool(void);
static int init_listen4(char *ip4, int port, int max_link);

//线程函数
void * test_server4(unsigned int thread_para[]);

int main(int argc, char *argv[])//客户端驱动
{
   //临时变量
   int            i, j, rc;

   int            sock_listen;    //监听套接字
   int            sock_cli;    //客户端连接
   int            listen_index;

   int            epfd;
   int             nfds;
   struct epoll_event    ev;
   struct epoll_event    events[LISTEN_MAX];

   socklen_t        addrlen;    //地址信息长度
   struct sockaddr_in    addr4;        //IPv4地址结构

   //线程池初始化
   rc = init_thread_pool();
   if (0 != rc) exit(-1);

   //初始化服务监听
   for(i = 0; i < LISTEN_MAX; i++) {
       sprintf(s_listens[i].ip4, "%s", SERVER_IP);
       s_listens[i].port = 8000 + i;
       //创建监听
       rc = init_listen4(s_listens[i].ip4, s_listens[i].port, 64);
       if (0 > rc) {
           fprintf(stderr, "无法创建服务器监听于%s:%d\r\n", s_listens[i].ip4, s_listens[i].port);
           exit(-1);
       }
       s_listens[i].fd = rc;
   }

   //设置集合
   epfd = epoll_create(8192);
   for (i = 0; i < LISTEN_MAX; i++) {
       //加入epoll事件集合
       ev.events = EPOLLIN;
       ev.data.u32 = i;//记录listen数组下标
       if (epoll_ctl(epfd, EPOLL_CTL_ADD, s_listens[i].fd, &ev) < 0) {
           fprintf(stderr, "向epoll集合添加套接字失败(fd =%d)\r\n", rc);
           exit(-1);
       }
   }


   //服务循环
   for( ; ; ) {
       //等待epoll事件
       nfds = epoll_wait(epfd, events, LISTEN_MAX, -1);
       //处理epoll事件
       for(i = 0; i < nfds; i++) {
           //接收客户端连接
           listen_index = events[i].data.u32;
           sock_listen = s_listens[listen_index].fd;
           addrlen = sizeof(struct sockaddr_in);
           bzero(&addr4, addrlen);
           sock_cli = accept(sock_listen, (struct sockaddr *)&addr4, &addrlen);
           if(0 > sock_cli) {
               fprintf(stderr, "接收客户端连接失败\n");
               continue;
           }
           //查询空闲线程对
           for(j = 0; j < THREAD_MAX; j++) {
               if (0 == s_thread_para[j][0]) break;
           }
           if (j >= THREAD_MAX) {
               fprintf(stderr, "线程池已满, 连接将被放弃\r\n");
               shutdown(sock_cli, SHUT_RDWR);
               close(sock_cli);
               continue;
           }
           //复制有关参数
           s_thread_para[j][0] = 1;//设置活动标志为"活动"
           s_thread_para[j][1] = sock_cli;//客户端连接
           s_thread_para[j][2] = listen_index;//服务索引
           //线程解锁
           pthread_mutex_unlock(s_mutex + j);
       }//end of for(i;;)
   }//end of for(;;)

   exit(0);
}

static int init_thread_pool(void)
{
   int    i, rc;

   //初始化线程池参数
   for(i = 0; i < THREAD_MAX; i++) {
       s_thread_para[i][0] = 0;//设置线程占用标志为"空闲"
       s_thread_para[i][7] = i;//线程池索引
       pthread_mutex_lock(s_mutex + i);//线程锁
   }

   //创建线程池
   for(i = 0; i < THREAD_MAX; i++) {
       rc = pthread_create(s_tid + i, 0, (void *)test_server4, (void *)(s_thread_para[i]));
       if (0 != rc) {
           fprintf(stderr, "线程创建失败\n");
           return(-1);
       }
   }

   //成功返回
   return(0);
}

static int init_listen4(char *ip4, int port, int max_link)
{
   //临时变量
   int            sock_listen4;
   struct sockaddr_in    addr4;
   unsigned int        optval;
   struct linger        optval1;

   //初始化数据结构
   bzero(&addr4, sizeof(addr4));
   inet_pton(AF_INET, ip4, &(addr4.sin_addr));
   addr4.sin_family = AF_INET;
   addr4.sin_port = htons(port);

   //创建SOCKET
   sock_listen4 = socket(AF_INET, SOCK_STREAM, 0);
   if (0 > sock_listen4) return(-1);

   //设置SO_REUSEADDR选项(服务器快速重起)
   optval = 0x1;
   setsockopt(sock_listen4, SOL_SOCKET, SO_REUSEADDR, &optval, 4);

   //设置SO_LINGER选项(防范CLOSE_WAIT挂住所有套接字)
   optval1.l_onoff = 1;
   optval1.l_linger = 60;
   setsockopt(sock_listen4, SOL_SOCKET, SO_LINGER, &optval1, sizeof(struct linger));

   if (0 > bind(sock_listen4, (struct sockaddr *)&addr4, sizeof(addr4))) {
       close(sock_listen4);
       return(-1);
   }

   if (0 > listen(sock_listen4, max_link)) {
       close(sock_listen4);
       return(-1);
   }

   return(sock_listen4);
}


void * test_server4(unsigned int thread_para[])
{
   //临时变量
   int        pool_index;    //线程池索引
   int        sock_cli;    //客户端连接
   int        listen_index;    //监听索引

   char        buff[32768];    //传输缓冲区
   char        *p;
   int        i, j, len;

   //线程脱离创建者
   pthread_detach(pthread_self());
   pool_index = thread_para[7];

wait_unlock:

   pthread_mutex_lock(s_mutex + pool_index);//等待线程解锁

   //线程变量内容复制
   sock_cli = thread_para[1];//客户端连接
   listen_index = thread_para[2];//监听索引

   //接收请求
   len = recv(sock_cli, buff, 32768, MSG_NOSIGNAL);

   //构造响应
   p = buff;
   //HTTP头
   p += sprintf(p, "HTTP/1.1 200 OK\r\n");
   p += sprintf(p, "Content-Type: text/html\r\n");
   p += sprintf(p, "Connection: closed\r\n\r\n");
   //页面
   p += sprintf(p, "<html>\r\n<head>\r\n");
   p += sprintf(p, "<meta content=\"text/html; charset=UTF-8\" http-equiv=\"Content-Type\">\r\n");
   p += sprintf(p, "</head>\r\n");
   p += sprintf(p, "<body style=\"background-color: rgb(229, 229, 229);\">\r\n");

   p += sprintf(p, "<center>\r\n");
   p += sprintf(p, "<H3>连接状态</H3>\r\n");
   p += sprintf(p, "<p>服务器地址 %s:%d</p>\r\n", s_listens[listen_index].ip4, s_listens[listen_index].port);
   j = 0;
   for(i = 0; i < THREAD_MAX; i++) {
       if (0 != s_thread_para[i][0]) j++;
   }
   p += sprintf(p, "<H3>线程池状态</H3>\r\n");
   p += sprintf(p, "<p>线程池总数 %d 活动线程总数 %d</p>\r\n", THREAD_MAX, j);
   p += sprintf(p, "</center></body></html>\r\n");
   len = p - buff;

   //发送响应
   send(sock_cli, buff, len, MSG_NOSIGNAL);

   //释放连接
   shutdown(sock_cli, SHUT_RDWR);
   close(sock_cli);

   //线程任务结束
   thread_para[0] = 0;//设置线程占用标志为"空闲"
   goto wait_unlock;

   pthread_exit(NULL);
}