//http://blog.csdn.net/ctrl_qun/article/details/52524086
//一对多服务器网络sock
#include<stdio.h>
#include<stdlib.h>
#include<netinet/in.h>
#include<sys/socket.h>
#include<arpa/inet.h>
#include<string.h>
#include<unistd.h>
#define BACKLOG 5 //完成三次握手但没有accept的队列的长度
#define CONCURRENT_MAX 8 //应用层同时可以处理的连接
#define SERVER_PORT 11332
#define BUFFER_SIZE 1024
#define QUIT_CMD ".quit"
int client_fds[CONCURRENT_MAX];
int main(int argc, const char * argv[])
{
char input_msg[BUFFER_SIZE];
char recv_msg[BUFFER_SIZE];
//本地地址
struct sockaddr_in server_addr;
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(SERVER_PORT);
server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
bzero(&(server_addr.sin_zero), 8);
//创建socket
int server_sock_fd = socket(AF_INET, SOCK_STREAM, 0);
if(server_sock_fd == -1)
{
perror("socket error");
return 1;
}
//绑定socket
int bind_result = bind(server_sock_fd, (struct sockaddr *)&server_addr, sizeof(server_addr));
if(bind_result == -1)
{
perror("bind error");
return 1;
}
//listen
if(listen(server_sock_fd, BACKLOG) == -1)
{
perror("listen error");
return 1;
}
//fd_set
fd_set server_fd_set;
int max_fd = -1;
struct timeval tv; //超时时间设置
while(1)
{
tv.tv_sec = 20;
tv.tv_usec = 0;
FD_ZERO(&server_fd_set);
FD_SET(STDIN_FILENO, &server_fd_set);
if(max_fd <STDIN_FILENO)
{
max_fd = STDIN_FILENO;
}
//printf("STDIN_FILENO=%d\n", STDIN_FILENO);
//服务器端socket
FD_SET(server_sock_fd, &server_fd_set);
// printf("server_sock_fd=%d\n", server_sock_fd);
if(max_fd < server_sock_fd)
{
max_fd = server_sock_fd;
}
//客户端连接
for(int i =0; i < CONCURRENT_MAX; i++)
{
//printf("client_fds[%d]=%d\n", i, client_fds[i]);
if(client_fds[i] != 0)
{
FD_SET(client_fds[i], &server_fd_set);
if(max_fd < client_fds[i])
{
max_fd = client_fds[i];
}
}
}
int ret = select(max_fd + 1, &server_fd_set, NULL, NULL, &tv);
if(ret < 0)
{
perror("select 出错\n");
continue;
}
else if(ret == 0)
{
printf("select 超时\n");
continue;
}
else
{
//ret 为未状态发生变化的文件描述符的个数
if(FD_ISSET(STDIN_FILENO, &server_fd_set))
{
printf("发送消息:\n");
bzero(input_msg, BUFFER_SIZE);
fgets(input_msg, BUFFER_SIZE, stdin);
//输入“.quit"则退出服务器
if(strcmp(input_msg, QUIT_CMD) == 0)
{
exit(0);
}
for(int i = 0; i < CONCURRENT_MAX; i++)
{
if(client_fds[i] != 0)
{
printf("client_fds[%d]=%d\n", i, client_fds[i]);
send(client_fds[i], input_msg, BUFFER_SIZE, 0);
}
}
}
if(FD_ISSET(server_sock_fd, &server_fd_set))
{
//有新的连接请求
struct sockaddr_in client_address;
socklen_t address_len;
int client_sock_fd = accept(server_sock_fd, (struct sockaddr *)&client_address, &address_len);
printf("new connection client_sock_fd = %d\n", client_sock_fd);
if(client_sock_fd > 0)
{
int index = -1;
for(int i = 0; i < CONCURRENT_MAX; i++)
{
if(client_fds[i] == 0)
{
index = i;
client_fds[i] = client_sock_fd;
break;
}
}
if(index >= 0)
{
printf("新客户端(%d)加入成功 %s:%d\n", index, inet_ntoa(client_address.sin_addr), ntohs(client_address.sin_port));
}
else
{
bzero(input_msg, BUFFER_SIZE);
strcpy(input_msg, "服务器加入的客户端数达到最大值,无法加入!\n");
send(client_sock_fd, input_msg, BUFFER_SIZE, 0);
printf("客户端连接数达到最大值,新客户端加入失败 %s:%d\n", inet_ntoa(client_address.sin_addr), ntohs(client_address.sin_port));
}
}
}
for(int i =0; i < CONCURRENT_MAX; i++)
{
if(client_fds[i] !=0)
{
if(FD_ISSET(client_fds[i], &server_fd_set))
{
//处理某个客户端过来的消息
bzero(recv_msg, BUFFER_SIZE);
long byte_num = recv(client_fds[i], recv_msg, BUFFER_SIZE, 0);
if (byte_num > 0)
{
if(byte_num > BUFFER_SIZE)
{
byte_num = BUFFER_SIZE;
}
recv_msg[byte_num] = '\0';
printf("客户端(%d):%s\n", i, recv_msg);
}
else if(byte_num < 0)
{
printf("从客户端(%d)接受消息出错.\n", i);
}
else
{
FD_CLR(client_fds[i], &server_fd_set);
client_fds[i] = 0;
printf("客户端(%d)退出了\n", i);
}
}
}
}
}
}
return 0;
}