Socket connet的一些疑问

2013-11-04 08:03:14 285 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

Java Socket重要参数讲解 Java Socket重要参数讲解 Socket参数定义在public interface SocketOptions中 TCP_NODELAY SO_BINDADDR SO_REUSEADDR SO_LINGER SO_TIMEOUT SO_SNDBUF/SO_RCVBUF SO_KEEPALIVE SO_OOBINLINE 除TCP_NODELAY这个参数为，其阅读详情

基于TCP协议， client链接server。
client程序如下：



........

result = connect(vars->clientsocketfd,(struct sockaddr *)&vars->client,sizeof(struct sockaddr));

if( result == 0 )				

 return true;

else if(result == -1)

{

    timeval    tm  ;

    fd_set     set ;

    int  len   = sizeof(int) ;

    int  error =           -1 ;

    tm.tv_sec  =            0 ;

    tm.tv_usec = timeout*1000 ;



    FD_ZERO( &set ) ;

    FD_SET(vars->clientsocketfd, &set);

    if( select((int)vars->clientsocketfd + 1 , NULL, &set, NULL, &tm) > 0)

    {

	if （ getsockopt(vars->clientsocketfd, SOL_SOCKET, SO_ERROR, (char *)&error, &len) ==0 )

	if(error == 0) 			

		return true;

    }	

}

......

Server 代码



.....

if( listen(vars->serversocketfd,1) == -1)

	return false;

struct sockaddr_in           clientaddr         ;

socklen_t len           =    sizeof(clientaddr) ;

char                         buffer[20]         ;

vars->clientsocketfd    =    accept(vars->serversocketfd,(struct sockaddr*)&clientaddr,&len) ;

if( vars->clientsocketfd   !=   INVALID_SOCKET  )

{

   ...........

   return true;

}

......

当client第一次连接上 server，此时可以正常通信。
但是当client端关闭socket,再次链接server端,
为什么client端还是显示连接成功？
而且都是每次走 result == -1，error== 0这个逻辑。

请问为什么会出现这个问题？

...全文

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yikesong321

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yikesong321 2013-11-05

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Client端所有代码



Bool SocketManager::openAsClient(String hostName,Int portNumber,TransferMode protocol,UInt timeout)
{
		Log log(moduleName(), "SocketManager openAsClient");
		int nRecvBuf=128*1024;//设置为128kb
		int nSendBuf=128*1024;//设置为128Kb

		if(! (json::isIP(hostName)))
			return false;
		if(portNumber  <= 1024)
			return false;
		vars->asServer = 0;
		vars->asClient = 1;

		// Close Socket
		closeSocket();


		vars->hostName     =   hostName    ;
		vars->portNumber   =   portNumber  ;
		vars->transferMode =   protocol    ;
		vars->timeOut      =   timeout     ;


		// Create Socket
		if(protocol == TM_UDP)
			vars->clientsocketfd = socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
		else if(protocol == TM_TCP )
			vars->clientsocketfd = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
		else
		{
			log.error("Protocol Not Support");
			return FALSE;
		}

		if(vars->clientsocketfd < 0)
		{
			log.error((String)" open socket fail " + vars->clientsocketfd);
			return FALSE;
		}
		//Set recvBuf  cache
		setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_RCVBUF,(const char*)&nRecvBuf,sizeof(int));
		//set sendBuf  cache
		setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_SNDBUF,(const char*)&nSendBuf,sizeof(int));

		// Set FD   non   Blocking
		if (fcntl(vars->clientsocketfd, F_SETFL, O_NONBLOCK) == -1)
		{
				log.error("Set Client non blocking mode failed");
				return FALSE;
		}


		//convert IP  to Net  Byte Order
		utility::memorySet(0,&vars->client,sizeof(struct sockaddr_in));
		vars->client.sin_family =             AF_INET ;
		vars->client.sin_port   =   htons(portNumber) ;
		if(inet_pton(AF_INET,(const char*)hostName.dataA(),&vars->client.sin_addr) != 1)
			    log.error("Transfer  IP  To  net byte  Fail.");

		//Connect to Server
				int result = 0;
				result     = connect(vars->clientsocketfd,(struct sockaddr *)&vars->client,sizeof(vars->client)) ;
				if( result == 0)
						return true;
				else if((errno == EINPROGRESS))
				{
						timeval    tm  ;
						fd_set     set ;
						Int  len   = sizeof(int) ;
						int  socketERROR =           -1 ;
						tm.tv_sec  =            0 ;
						tm.tv_usec = timeout*1000 ; //超时时间

						FD_ZERO( &set ) ;
						FD_SET(vars->clientsocketfd, &set);
						if( select((int)vars->clientsocketfd + 1 , NULL, &set, NULL, &tm) > 0)
						{
							if(FD_ISSET(vars->clientsocketfd,&set))
							{
								if(getsockopt(vars->clientsocketfd, SOL_SOCKET, SO_ERROR, (void *)&socketERROR, (socklen_t *)&len) == 0)
								{
										if(socketERROR == 0)
										{
												log.error((String)" Connect Server successful  Result :  " + result);
												return true;
										}
								}
							}
						}
				}

				log.error("Time out , connect Server Fail.");
				return FALSE;
}

yikesong321 2013-11-05

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你是说这里绑定的？？ // binder Server Address


  utility::memorySet(0,&vars->server,sizeof(struct sockaddr_in));
                vars->server.sin_family      =  AF_INET;
                vars->server.sin_port        =  htons(portNumber);//转接成网络字节函数
                vars->server.sin_addr.s_addr =  htonl(INADDR_ANY);//开放所有网卡地址
 
                if(bind(vars->serversocketfd,(struct sockaddr *)&vars->server,sizeof(vars->server)) == -1)
                {
                    log.error(" BINDER SERVER FAIL");
                    return  false;
                }

yikesong321 2013-11-05

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server端。在socket的时候绑定了端口。 Server端的全部代码：


Bool SocketManager::openAsServer(Int portNumber,TransferMode protocol,UInt timeout)
{
		Log log(moduleName(), "SocketManager openAsServer");
		int nRecvBuf=128*1024;//设置为128kb
		int nSendBuf=128*1024;//设置为128Kb
		if((vars->portNumber != portNumber) || (vars->transferMode != protocol) || (vars->serversocketfd < 0))
		{
				if(portNumber  <= 1024)
				{
					log.error("portNumber Must bigger than 1024");
					return false;
				}

				// Close Socket
				closeSocket();

				vars->asClient    =    0;
				vars->asServer    =    1;

				vars->portNumber   = portNumber;
				vars->transferMode =   protocol;
				vars->timeOut      =    timeout;



				if(protocol == TM_UDP)
						vars->serversocketfd = socket(AF_INET,SOCK_DGRAM,0);
				else if(protocol == TM_TCP )
						vars->serversocketfd = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
				else
				{
						log.error("Not Support");
						return false;
				}

				if(vars->serversocketfd < 0)
				{
					log.error(" open socket fail ");
					return false;
				}
				//Set recvBuf  cache
				setsockopt(vars->serversocketfd,SOL_SOCKET,SO_RCVBUF,(const char*)&nRecvBuf,sizeof(int));

				//set sendBuf  cache
				setsockopt(vars->serversocketfd,SOL_SOCKET,SO_SNDBUF,(const char*)&nSendBuf,sizeof(int));

				//  binder  Server Address 你是说这里绑定的？？
				utility::memorySet(0,&vars->server,sizeof(struct sockaddr_in));
				vars->server.sin_family      =  AF_INET;
				vars->server.sin_port        =  htons(portNumber);//转接成网络字节函数
				vars->server.sin_addr.s_addr =  htonl(INADDR_ANY);//开放所有网卡地址

				if(bind(vars->serversocketfd,(struct sockaddr *)&vars->server,sizeof(vars->server)) == -1)
				{
					log.error(" BINDER SERVER FAIL");
					return  false;
				}

				// set non block
				if (fcntl(vars->serversocketfd, F_SETFL, O_NONBLOCK) == -1)
							log.error("non block mode failed");
				// UDP  Protocol   Do not Need  listen  and  accept client
				if(protocol == TM_UDP)
				{
					bool bBroadcast=true;
					setsockopt(vars->serversocketfd,SOL_SOCKET,SO_BROADCAST,(const char*)&bBroadcast,sizeof(bool));
					return TRUE;
				}
				// listen   ClientS   and  accept client
				if(protocol == TM_TCP  )
				{
							if( listen(vars->serversocketfd,1) == -1)
							{
								log.error(" Listen Fail");
								return false;
							}

							Timer timenow ;
							timenow.start();

							while(true)
							{
									if(timenow.check() < timeout )
									{
											struct sockaddr_in        clientaddr ;
											socklen_t   len = sizeof(clientaddr) ;
											char  buffer[20]   ;
											vars->clientsocketfd  = accept(vars->serversocketfd,(struct sockaddr*)&clientaddr,&len);
											if(  vars->clientsocketfd   > 0)
											{
												inet_ntop(AF_INET,&(clientaddr.sin_addr.s_addr),buffer,20);
												log.error((String)"Client IP :"+ (String)buffer);
												//Set recvBuf  cache
												setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_RCVBUF,(const char*)&nRecvBuf,sizeof(int));
												//set sendBuf  cache
												setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_SNDBUF,(const char*)&nSendBuf,sizeof(int));

												// set client socket fd no blocking
												// set non block
												if (fcntl(vars->clientsocketfd, F_SETFL, O_NONBLOCK) == -1)
														log.error("client non block mode failed");
												return  true;
											}
									}
									else
									{
											log.error(" Time Out. Accept CLient Fail.");
											return false;
									}
							}
				}
}

max_min_ 2013-11-05

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引用 5 楼 yikesong321 的回复:

client端代码：


//Connect to Server
int result = 0;
result     = connect(vars->clientsocketfd,(struct sockaddr *)&vars->client,sizeof(vars->client)) ;
if( result == 0)
		    return true;
else if((errno == EINPROGRESS))
{
	timeval    tm  ;
	fd_set     set ;
	Int  len   = sizeof(int) ;
	int  socketERROR =           -1 ;
	tm.tv_sec  =            0 ;
	tm.tv_usec = timeout*1000 ;
	FD_ZERO( &set ) ;
	FD_SET(vars->clientsocketfd, &set);
	if( select((int)vars->clientsocketfd + 1 , NULL, &set, NULL, &tm) > 0)
	{
			if(FD_ISSET(vars->clientsocketfd,&set))
			{
					if(getsockopt(vars->clientsocketfd, SOL_SOCKET, SO_ERROR, (void *)&socketERROR, &len) == 0)
					{
							if(socketERROR == 0)
							{
								log.error((String)" Connect Server successful  Result :  " + result);
								return true;
							}
					}
			}
	}
}

不是这个，我说的是你在建立socket的时候，是否绑定了端口号呢？把绑定端口号服务端客户端的代码贴上来看看！

yikesong321 2013-11-05

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client端代码：


//Connect to Server
int result = 0;
result     = connect(vars->clientsocketfd,(struct sockaddr *)&vars->client,sizeof(vars->client)) ;
if( result == 0)
		    return true;
else if((errno == EINPROGRESS))
{
	timeval    tm  ;
	fd_set     set ;
	Int  len   = sizeof(int) ;
	int  socketERROR =           -1 ;
	tm.tv_sec  =            0 ;
	tm.tv_usec = timeout*1000 ;
	FD_ZERO( &set ) ;
	FD_SET(vars->clientsocketfd, &set);
	if( select((int)vars->clientsocketfd + 1 , NULL, &set, NULL, &tm) > 0)
	{
			if(FD_ISSET(vars->clientsocketfd,&set))
			{
					if(getsockopt(vars->clientsocketfd, SOL_SOCKET, SO_ERROR, (void *)&socketERROR, &len) == 0)
					{
							if(socketERROR == 0)
							{
								log.error((String)" Connect Server successful  Result :  " + result);
								return true;
							}
					}
			}
	}
}

yikesong321 2013-11-05

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这个格式有问题。重新传一下 server端的代码


if( listen(vars->serversocketfd,1) == -1)
{
	log.error(" Server Socket Listen Fail.");
	return false;
}
	Timer     timenow ;
	timenow.start()   ;
while(true)
{
	if(timenow.check() < timeout )
	{
		struct sockaddr_in           clientaddr         ;
		socklen_t len           =    sizeof(clientaddr) ;
		char                         buffer[20]         ;
		vars->clientsocketfd    =    accept(vars->serversocketfd,(struct sockaddr*)&clientaddr,&len) ;
		if( vars->clientsocketfd   !=   INVALID_SOCKET  )
		{
					inet_ntop(  AF_INET,  &(clientaddr.sin_addr.S_un.S_addr) ,   buffer,    20) ;
					log.error((String)"Accept Client Successful   IP  :      "+ (String)buffer) ;
					//Set recvBuf  cache 128KB
					setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_RCVBUF,(const char*)&nRecvBuf,sizeof(int));
					//set sendBuf  cache 128KB
					setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_SNDBUF,(const char*)&nSendBuf,sizeof(int));
					int     result   =  ioctlsocket(vars->clientsocketfd,FIONBIO,&flag) ;
					if (    result !=  NO_ERROR   ) 
					{
						log.error("non block mode failed  " );
						return false;
					}
					return  true;
		}
	}
	else
	{
			log.error((String)"Time out , Accept Client  Failed");
	  	return false;
	} 
}

yikesong321 2013-11-05

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恩。下面是2端建立连接的代码这是Server端，2端的socket都被我设置成了非阻塞。


while(true)
{
// 设置超过规定的timeout就退出											        if(timenow.check() < timeout )
{												struct sockaddr_in        clientaddr ;												socklen_t   len = sizeof(clientaddr) ;												char  buffer[20]   ;												vars->clientsocketfd  = accept(vars->serversocketfd,(struct sockaddr*)&clientaddr,&len);												if(  vars->clientsocketfd   > 0)												{													inet_ntop(AF_INET,&(clientaddr.sin_addr.s_addr),buffer,20);													log.error((String)"Client IP :"+ (String)buffer);													//Set recvBuf  cache													setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_RCVBUF,(const char*)&nRecvBuf,sizeof(int));													//set sendBuf  cache													setsockopt(vars->clientsocketfd,SOL_SOCKET,SO_SNDBUF,(const char*)&nSendBuf,sizeof(int));													if (fcntl(vars->clientsocketfd, F_SETFL, O_NONBLOCK) == -1)															 log.error("client non block mode failed");													return  true;												}
}
else
{												log.error(" Time Out. Accept CLient Fail.");												              return false;											}
}

这是client端的代码，socket也是非阻塞的


while(true)
{
// 设置超时退出
if(timenow.check() < timeout )
{
int result = 0;
result  = connect(vars->clientsocketfd,(struct sockaddr *)&vars->client,sizeof(vars->client)) ;
if( result == 0)
	return true;
else if((errno == EINPROGRESS))
{
	timeval    tm  ;
	fd_set     set ;
	Int  len   = sizeof(int) ;
	int  socketERROR =           -1 ;
	tm.tv_sec  =            0 ;
	tm.tv_usec = timeout*1000 ;

	FD_ZERO( &set ) ;
	FD_SET(vars->clientsocketfd, &set);
if( select((int)vars->clientsocketfd + 1 , NULL, &set, NULL, &tm) > 0)
{

if(FD_ISSET(vars->clientsocketfd,&set))
{
if(getsockopt(vars->clientsocketfd, SOL_SOCKET, SO_ERROR, (void *)&socketERROR, (socklen_t *)&len) == 0)
{												 if(socketERROR == 0)												{														log.error((String)" Connect Server successful  Result :  " + result);																												return true;												}
}
}
}
}
}
else
{
	log.error("Time out , connect Server Fail.");
	return FALSE;
}
}

beginning1126 2013-11-04

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server端代码是循环执行的吗？

max_min_ 2013-11-04

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把两端的建立socket这些贴出来看看！端口是否绑定成功？怀疑是端口问题呢！

Socket connet的一些疑问

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