[应用方案] 移植MQTT协议

#if !defined(SOCKET_ERROR)

    /** error in socket operation */

   

#define SOCKET_ERROR -1



#endif



#define INVALID_SOCKET SOCKET_ERROR







#include "transport.h"



   

static int MQTTSocket = INVALID_SOCKET;



/*发包函数*/

int transport_sendPacketBuffer(int sock, unsigned char* buf, int buflen)

{

    int rc = 0;

    rc=lwip_write(sock,buf,buflen);

    return rc;

}



int transport_getdata(unsigned char* buf, int count)

{

    int rc = lwip_recv(MQTTSocket, buf, count, 0);

    return rc;

}

/*获取数据函数*/

int transport_getdatanb(void *sck, unsigned char* buf, int count)

{

    int sock = *((int *)sck);     /* sck: pointer to whatever the system may use to identify the transport */

    /* this call will return after the timeout set on initialization if no bytes;

       in your system you will use whatever you use to get whichever outstanding

       bytes your socket equivalent has ready to be extracted right now, if any,

       or return immediately */

    int rc = lwip_recv(sock, buf, count, 0);   

    if (rc == -1) {

        /* check error conditions from your system here, and return -1 */

        return 0;

    }

    return rc;

}

/*开启传输函数*/

int transport_open(char* addr, int port)

{

    struct hostent *server;

    struct sockaddr_in serv_addr;

    int timeout = 1000;

  

         MQTTSocket = lwip_socket(AF_INET, SOCK_STREAM, 0);

         if (MQTTSocket < 0)

         {

               

                return -1;

         }

         

      server = lwip_getsockname(addr);         

          if(server == NULL)

            {

                lwip_close(MQTTSocket);

                return -1;

            }

            memset(&serv_addr,0,sizeof(serv_addr));

            

            serv_addr.sin_family = 2;      

            serv_addr.sin_port = htons(port);   

            //serv_addr.sin_addr.s_addr = inet_addr(addr);

            memcpy(&serv_addr.sin_addr.s_addr,server->h_addr,server->h_length);

            memset(&(serv_addr.sin_zero), 0, sizeof(serv_addr.sin_zero));  

            if (lwip_connect(MQTTSocket,(struct sockaddr *)&serv_addr, sizeof(struct sockaddr)) == -1)

            {

                lwip_close(MQTTSocket);

        return -1;

            }  

            

      lwip_getsockopt(MQTTSocket, SOL_SOCKET, SO_RCVTIMEO, (char*)&timeout,sizeof(timeout));



    return MQTTSocket;

}

/*关闭传输函数*/

int transport_close(int sock)

{

  int rc;



    rc = lwip_shutdown(sock, SHUT_WR);

    rc = lwip_recv(sock, NULL, (size_t)0, 0);

    rc = lwip_close(sock);



    return rc;

}