Client.cpp

#include"Client.h"

using namespace std;

//客户端类成员函数
//客户端类构造函数
Client::Client()
{
	//初始化要连接的服务器地址和端口
	serverAddr.sin_family = AF_INET;
	serverAddr.sin_port = htons(SERVER_PORT);
	inet_pton(AF_INET,SERVER_IP,&serverAddr.sin_addr.s_addr);
	
	//初始化socket
	sock = 0;

	//初始化进程号
	pid = 0;

	//客户端状态
	isClientwork = true;

	//epoll fd
	epfd = 0;
}

//连接服务器
void Client::Connect()
{
	cout<<"Connect Server: "<<SERVER_IP<<" : "<<SERVER_PORT<<endl;
	
	//创建socket
	sock = socket(AF_INET,SOCK_STREAM,0);
	if(sock<0)
	{
		perror("socker error: ");
		exit(1);
	}
	
	//连接服务端
	if(connect(sock,(struct sockaddr*)&serverAddr,sizeof(serverAddr))<0)
	{
		perror("connect error: ");
		exit(1);
	}

	//创建管道，其中fd[0]用于父进程读，fd[1]用于子进程写
	if(pipe(pipe_fd)<0)
	{
		perror("pipe error:");
		exit(1);
	}

	//创建epoll
	epfd = epoll_create(EPOLL_SIZE);

	if(epfd<0)
	{
		perror("epoll_create error:");
		exit(1);
	}

	//将sock和管道读端描述符都添加到内核事件表中
	addfd(epfd,sock,true);
	addfd(epfd,pipe_fd[0],true);
}

//断开连接，清理并关闭文件描述符
void Client::Close()
{
	if(pid)
	{
		//关闭父进程的管道和sock
		close(pipe_fd[0]);
		close(sock);
	}else{
		//关闭子进程的管道
		close(pipe_fd[1]);
	}
}

//启动客户端
void Client::Start()
{
	//epoll 事件队列
	static struct epoll_event events[2];

	//连接服务器
	Connect();

	//创建子进程
	pid = fork();
	
	//如果子进程失败则退吹
	if(pid<0)
	{
		perror("fork error: ");
		close(sock);
		exit(1);
	}else if(pid == 0)
	{
		//进入子进程执行流程
		//子进程负责写入管道，因此先关闭读端
		close(pipe_fd[0]);
		
		//输入exit可以退出聊天室
		cout<<"Please input 'exit' to exit the chat room!"<<endl;
		cout<<"\\ + ClientID to private chat"<<endl;
	
		//如果客户端运行正常则不断读取输入发送给服务端
		while(isClientwork)
		{
			//清空结构体
			memset(msg.content,0,sizeof(msg.content));
			fgets(msg.content,BUF_SIZE,stdin);
			
			//如果客户输入exit,退出
			if(strncasecmp(msg.content,EXIT,strlen(EXIT))==0)
				isClientwork = 0;
			else	//子进程将信息写入管道
			{	
				//清空发送缓存
				memset(send_buf,0,BUF_SIZE);
				//结构体转换为字符串
				memcpy(send_buf,&msg,sizeof(msg));
				if(write(pipe_fd[1],send_buf,sizeof(send_buf))<0)
				{
					perror("fork error: ");
					exit(1);
				}
			}
		}	
	}else
	{
		//pid>0 父进程
		//父进程负责读管道数据,因此先关闭写端
		close(pipe_fd[1]);

		//主循环epoll_wait
		while(isClientwork)
		{
			int epoll_events_count = epoll_wait(epfd,events,2,-1);

			//处理就绪事件
			for(int i = 0;i<epoll_events_count;i++)
			{
				memset(recv_buf,0,sizeof(recv_buf));
				//服务端发来消息
				if(events[i].data.fd == sock)
				{
					//接收服务端广播消息
					int ret = recv(sock,recv_buf,BUF_SIZE,0);
					//清空结构体
					memset(&msg,0,sizeof(msg));
					//将发来的消息转换为结构体
					memcpy(&msg,recv_buf,sizeof(msg));

					//ret = 0   服务端关闭
					if(ret == 0)
					{
						cout<<"Server closed connection: "<<sock<<endl;
						close(sock);
						isClientwork = 0;
					}else
						cout<<msg.content<<endl;
				}
				//子进程写入事件发生，父进程处理并发送服务端
				else
				{
					//父进程从管道中读取数据
					int ret = read(events[i].data.fd,recv_buf,BUF_SIZE);
					//ret = 0
					if(ret == 0)
						isClientwork = 0;
					else
						//将从管道中读取的字符串信息发送给服务端
						send(sock,recv_buf,sizeof(recv_buf),0);
				}
			}//for
		}//while
	}
	Close();         //退出进程
}