• C++ Enet通信封装

    C++ Enet通信封装


    Enet底层封装的是UDP通信，本文介绍了enet如何实现可靠udp传输的代码封装

    接口封装

    1)User_Enet_Listen监听端口函数

    int User_Enet_Listen(const char *ip, int port, ENetHost **host)
{    
	ENetAddress address;  
    if(!strcmp(ip, "*"))
		ip = "0.0.0.0";
	if(enet_address_set_host_ip(&address, ip)){
		fprintf(stderr, "enet_address_set_host_ip %s fail", ip);
		return -1;
	}
    address.port = port;
    assert(host);
    *host = enet_host_create(&address, 1, 1, 0, 0);
    if(NULL==*host){
    	fprintf(stderr, "enet_host_create %s:%d fail", address.host, address.port);
    	return -1;
    }
	int size = 1024*1024*1024;
   	if(enet_socket_set_option((*host)->socket, ENET_SOCKOPT_RCVBUF, size)){
    	fprintf(stderr, "enet set server socket rcvbuf %d bytes fail", size);
    }
    return 0;
}

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    2)User_Enet_Accept接受链接函数

    int User_Enet_Accept(ENetHost *host, unsigned int timeout, ENetPeer **peer)
{
	int ret;
	ENetEvent event;
    ret = enet_host_service(host, &event, timeout);
	if(ret > 0){        
		if(event.type != ENET_EVENT_TYPE_CONNECT){
			if(event.type == ENET_EVENT_TYPE_RECEIVE)
                 enet_packet_destroy(event.packet);
			fprintf(stderr, "enet_host_service event type %d is not connect", event.type);
			return -1;
         }         
         assert(peer);
         *peer = event.peer;         
     }else if(0==ret){
         fprintf(stderr, "enet_host_service timeout %d", timeout);
         return -1;         
     }else{
         fprintf(stderr, "enet_host_service fail");
         return -1;
	}
	return 0;
}

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    3)User_Enet_Connect建立连接函数

    int User_Enet_Connect(const char *srv_ip, int srv_port, unsigned int conn_timeout, unsigned int rw_timeout, ENetHost **host, ENetPeer **peer)
{    
      assert(host);
     *host = enet_host_create(NULL, 1, 1, 0, 0);
     if(NULL==*host){
         fprintf(stderr, "enet_host_create fail");
         goto fail;
     }
     if(enet_socket_set_option((*host)->socket, ENET_SOCKOPT_RCVBUF, 1024*1024*1024)){
            fprintf(stderr, "enet set server socket rcvbuf 1M bytes fail");
     }
     
     ENetAddress srv_addr;
     if(enet_address_set_host_ip(&srv_addr, srv_ip)){
         fprintf(stderr, "enet_address_set_host_ip %s fail", srv_ip);
         goto fail;
     }
     srv_addr.port = srv_port;
     
     assert(peer);
     *peer = enet_host_connect(*host, &srv_addr, 1, 0); 
     if(*peer==NULL){
             fprintf(stderr, "enet_host_connect %s:%d fail", srv_ip, srv_port);
         goto fail;
     }
 
     enet_peer_timeout(*peer, 0, rw_timeout, rw_timeout);
     
     int cnt = 0;
     ENetEvent event;
 
     while(1){
         ret = enet_host_service(*host, &event, 1);
         if(ret == 0){    
             if(++cnt >= conn_timeout){ 
                    fprintf(stderr, "enet_host_service timeout %d", conn_timeout);
                 goto fail;
             }
         
         }else if(ret > 0){
             if(event.type != ENET_EVENT_TYPE_CONNECT){     
                     fprintf(stderr, "enet_host_service event type %d is not connect", event.type);
                     goto fail;
             }
             break; //connect successfully
 
         }else{
                 fprintf(stderr, "enet_host_service fail");        
             goto fail;
         }
     }
 
 #ifdef _DEBUG
     char local_ip[16], foreign_ip[16];
     ENetAddress local_addr;
 
     enet_socket_get_address((*host)->socket, &local_addr);
     enet_address_get_host_ip(&local_addr, local_ip, sizeof(local_ip));
     enet_address_get_host_ip(&(*peer)->address, foreign_ip, sizeof(foreign_ip));
     
     printf("%s:%d connected to %s:%d", local_ip, loca_addr.port, foreign_ip, (*peer)->address.port);
 #endif 
     return 0;     
 fail:
     if(*host) enet_host_destroy(*host); 
     return -1;
 }

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    4)User_Enet_DisConnect断开连接函数

     int User_Enet_DisConnect(ENetHost *host, ENetPeer *peer)
{
     int ret;
  
  #ifdef _DEBUG
     char local_ip[16], foreign_ip[16];
     ENetAddress local_addr;
  
     enet_socket_get_address(host->socket, &local_addr);
     enet_address_get_host_ip(&local_addr, local_ip, sizeof(local_ip));
     enet_address_get_host_ip(&peer->address, foreign_ip, sizeof(foreign_ip));
     
     printf("%s:%d is disconnected from %s:%d", local_ip, local_addr.port, foreign_ip, peer->address.port);
 #endif
 
     ENetEvent event;
     enet_peer_disconnect(peer, 0);
         
     while((ret = enet_host_service(host, &event, peer->roundTripTime)) > 0){
         switch (event.type){
         case ENET_EVENT_TYPE_RECEIVE:
             enet_packet_destroy (event.packet);
             break;
     
         case ENET_EVENT_TYPE_DISCONNECT:
             ret = 0;
             goto disconn_ok;
         }
     }
     ret = 0==ret ? 1 : -1;
 
     fprintf(stderr, "enet_host_service with timeout %d %s", peer->roundTripTime, 1==ret?"timeout":"failure");
     
     enet_peer_reset(conn->peer);
 
 disconn_ok:    
     enet_host_destroy(host);
     return ret;
 }

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    5)User_Enet_SendMsg发送数据函数

    int User_Enet_SendMsg(ENetHost *host, ENetPeer *peer, ENetPacket *packet)
  {
      int ret;
      
      if(enet_peer_send(peer, 0, packet)){
          fprintf(stderr, "enet send packet %lu bytes to peer fail", packet->dataLength);
          return -1;
      }
  
     ret = enet_host_service(host, NULL, peer->roundTripTime);
     if(ret >= 0){
         if(peer->state == ENET_PEER_STATE_ZOMBIE){
             fprintf(stderr, "enet peer state is zombie");
             return -1;
         }
         return packet->dataLength;
         
     }else{
         fprintf(stderr, "enet host service %u millsecond failure", peer->roundTripTime);
         return -1;
     }
 }
 
 int User_Enet_Send(ENetHost *host, ENetPeer *peer, const void *buf, size_t len)
 {
     int ret;
 
     ENetPacket *packet = enet_packet_create(buf, len, ENET_PACKET_FLAG_RELIABLE);
     if(NULL==packet){        
         fprintf(stderr, "enet create packet %lu bytes fail", sizeof(int)+len);
         return -1;
     }
 
     return User_Enet_SendMsg(host, peer, packet);
 }

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    6)User_Enet_RecvMsg接收数据函数

    int User_Enet_RecvMsg(ENetHost *host, ENetPeer *peer, ENetPacket **packet, unsigned int timeout)
  {
      int ret;
      ENetEvent event;
  
      ret = enet_host_service(host, &event, timeout);
      if(ret > 0){
          if(event.peer != peer){
              fprintf(stderr, "enet receive peer is not matched");
             goto fail;
         }
         if(event.type != ENET_EVENT_TYPE_RECEIVE){
             fprintf(stderr, "enet receive event type %d is not ENET_EVENT_TYPE_RECEIVE", event.type);
             goto fail;
         }
         
         *packet = event.packet;
         return （*packet)->dataLength;
        
 fail:
         enet_packet_destroy(event.packet);
         return -1;
         
     }else {
         fprintf(stderr, "enet receive %u millsecond %s", timeout, ret?"failure":"timeout");
         return -1;        
     }
 }
 
 int User_Enet_Recv(ENetHost *host, ENetPeer *peer, void *buf, size_t maxlen, unsigned int timeout) 
 {
     ENetPacket *packet;
 
     if(-1==User_Enet_RecvMsg(host, peer, &packet, timeout))
         return -1;
 
     if(packet->dataLength > maxlen) {
         fprintf(stderr, "enet packet data length %d is greater than maxlen %lu", packet->dataLength, maxlen);
         return -1;
     }
 
     memcpy(buf, packet->data, packet->dataLength);
     enet_packet_destroy(packet);
     
     return packet->dataLength;
 }

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    7)User_Enet__WaitAck 等待所有确认函数
    发送数据的确认，需根据对端状态判断是否断线

     int User_Enet__WaitAck (ENetHost *host, ENetPeer *peer, unsigned int timeout)
  {
      int ret, cnt = 0;
      
      while((ret = enet_host_service(host, NULL, 1)) >= 0){        
          if(enet_peer_is_empty_sent_reliable_commands(peer, 0, 
              ENET_PROTOCOL_COMMAND_SEND_RELIABLE|ENET_PROTOCOL_COMMAND_SEND_FRAGMENT))
              return 0;
 
         if(peer->state == ENET_PEER_STATE_ZOMBIE){
             fprintf(stderr, "enet peer state is zombie");
             return -1;
         }
     
         if(0==ret && ++cnt>=timeout){
             return 1;
         }
     }
     
     fprintf(stderr, "enet host service fail");
     return -1;
 }

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    使用举例

    客户端：
    User_Enet_Connect->User_Enet_SendMsg或User_Enet_Send->User_Enet_WaitAck
    服务端：
    User_Enet_Listen->User_Enet_Accept->User_Enet_Recv或是User_Enet_RecvMsg

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  • 原文地址：https://blog.csdn.net/techenliu/article/details/132744386