cocos2dx socket 通信

本文由qinning199原创，转载请注明：http://www.cocos2dx.net/?p=167

最近做一个联网实时交互的游戏，游戏中需要使用socket保持长连接，来保证客户端与服务器端进行实时交互。以下贴出自己的一些代码：

因为socket通信部分需要使用多线程，整个流程如下：

1、首先起一个线程，来进行socket通信的连接

 int GameServer::connectThreadStart(){
 //    connect(GAMESERVER, CCString::create(GAMESERVER_PORT)->intValue());

     int errCode = 0;
     do{
         pthread_attr_t tAttr;
         errCode = pthread_attr_init(&tAttr);

         CC_BREAK_IF(errCode!=0);

         errCode = pthread_attr_setdetachstate(&tAttr, PTHREAD_CREATE_DETACHED);

         if (errCode!=0) {
             pthread_attr_destroy(&tAttr);
             break;
         }

         errCode = pthread_create(&m_gameThread, &tAttr, connectSocket, this);

     }while (0);
     return errCode;
 }

2、连接socket代码：

 void* GameServer::connectSocket(void* args)
 {
     connect("192.168.1.2", "3343");
     return NULL;
 }

再此处进行socket连接，如果连接成功之后，将会通知主线程，连接已经成功，此处我们使用了cocos2dx高级开发教程中封装的MTNotificationQueue进行子线程向主线程的通信，如果你不了解，可以自己去百度

 int GameServer::connect(const char* ip, unsigned int port)
 {
     CCLOG("Client begin connect IP: %s:%d ",ip,port);
     struct sockaddr_in sa;
     struct hostent* hp;

     hp = gethostbyname(ip);
     if(!hp){
         return -1;
     }
     memset(&sa, 0, sizeof(sa));
     memcpy((char*)&sa.sin_addr, hp->h_addr, hp->h_length);
     sa.sin_family = hp->h_addrtype;
     sa.sin_port = htons(port);

     m_socketHandle = socket(sa.sin_family, SOCK_STREAM, 0);

     if(m_socketHandle < 0){
         printf( "failed to create socket\n" );
         return -1;
     }
     if(::connect(m_socketHandle, (sockaddr*)&sa, sizeof(sa)) < 0){
         printf( "failed to connect socket\n" );
         ::close(m_socketHandle);
         return -1;
     }

     CCLOG("Client connect OK ！ IP: %s:%d ",ip,port);

     MTNotificationQueue::sharedNotificationQueue()->postNotification("connectok", NULL);
     return 0;
 }

3、通知主线程之后，主线程将会负责开启新的线程进行recv监听，监听服务器下发的数据

 void GameServer::initReceiveThread(CCObject* obj)
 {
     int errCode = 0;
     pthread_attr_t tAttr;
     errCode = pthread_attr_init(&tAttr);

     errCode = pthread_attr_setdetachstate(&tAttr, PTHREAD_CREATE_DETACHED);

     if (errCode!=0) {
         pthread_attr_destroy(&tAttr);
     }else{
         errCode = pthread_create(&m_gameThread, &tAttr, listenSocketData, this);
     }
     if(errCode == 0){
         CCLOG("Receive Thread OK!!!");
     }else{
         CCLOG("Receive Thread Error!!!!");
     }

     MTNotificationQueue::sharedNotificationQueue()->postNotification("jointable", NULL);
 }

开启socket通信接收函数

 void* GameServer::listenSocketData(void* obj)
 {
     byte buffer[5];
     string contents;
     int ret = 0;
     // 先接受4字节，获取服务返回长度
     bool rs = true;
     while(rs)
     {
         contents = "";
         ret = recv(m_socketHandle,buffer,4,0);
         // 服务器关闭
         if(ret == 0)
         {
 //            CCLog("Error: server close");
             rs = false;
         }
         if(ret == 4)
         {
             buffer[4]='\0';
             int packetlen = Utils::bytes2int(buffer);
             CCLOG("packetlen %d",packetlen);
             char buf[packetlen];
             int rets = 0;
             while((ret = recv(m_socketHandle,buf,packetlen-rets,0))>0)
             {
                 contents.append(buf,ret);
                 packetlen-=ret;
                 if(packetlen<=0)
                     break;
             }
             CCLog("recv content:%s\n",contents.c_str());
             CCString* str = CCString::create(Utils::getUnPackMsg(contents));
             MTNotificationQueue::sharedNotificationQueue()->postNotification("receivedata", str);
         }else {
             CCLog("Error: recv data Error %d",ret);
         }
     }
     return NULL;
 }

因为我们的cocos2dx客户端与服务器端约定，发送的前四个字节作为发送内容的字节长度，因此首先接收前四个字节，至此，一个多线程socket程序就完成了。