1 void loop_back(void)
 2 {
 3     int32_t ret = 0;
 4     
 5     /* Loopback Test */
 6         // TCP server loopback test
 7         if( (ret = loopback_tcps(SOCK_TCPS, gDATABUF, 5000)) < 0) {
 8             printf("SOCKET ERROR : %ld\r\n", ret);
 9         }
10     // UDP server loopback test
11         if( (ret = loopback_udps(SOCK_UDPS, gDATABUF, 3000)) < 0) {
12             printf("SOCKET ERROR : %ld\r\n", ret);
13         }
14 }

 1 int32_t loopback_tcps(uint8_t sn, uint8_t* buf, uint16_t port)
 2 {
 3    int32_t ret;
 4    uint16_t size = 0, sentsize=0;
 5 
 6 #ifdef _LOOPBACK_DEBUG_
 7    uint8_t destip[4];
 8    uint16_t destport;
 9 #endif
10 
11    switch(getSn_SR(sn))
12    {
13       case SOCK_ESTABLISHED : //Success to connect
14          if(getSn_IR(sn) & Sn_IR_CON)
15          {
16 #ifdef _LOOPBACK_DEBUG_
17             getSn_DIPR(sn, destip);    //获取客户端的ip地址
18             destport = getSn_DPORT(sn);    //获取客户端的端口号
19 
20             printf("%d:Connected - %d.%d.%d.%d : %d\r\n",sn, destip[0], destip[1], destip[2], destip[3], destport);
21 #endif
22             setSn_IR(sn,Sn_IR_CON);//设置socket的连接中断标志位
23          }
24          if((size = getSn_RX_RSR(sn)) > 0) // Don\'t need to check SOCKERR_BUSY because it doesn\'t not occur.
25          {
26             if(size > DATA_BUF_SIZE) size = DATA_BUF_SIZE;
27             ret = recv(sn, buf, size);
28 
29             if(ret <= 0) return ret;      // check SOCKERR_BUSY & SOCKERR_XXX. For showing the occurrence of SOCKERR_BUSY.
30             size = (uint16_t) ret;
31             sentsize = 0;
32 
33             while(size != sentsize)
34             {
35                 ret = send(sn, buf+sentsize, size-sentsize);
36                 if(ret < 0)
37                 {
38                     close(sn);
39                     return ret;
40                 }
41                 sentsize += ret; // Don\'t care SOCKERR_BUSY, because it is zero.
42             }
43          }
44          break;
45       case SOCK_CLOSE_WAIT :    //Closing state
46 #ifdef _LOOPBACK_DEBUG_
47          //printf("%d:CloseWait\r\n",sn);
48 #endif
49          if((ret = disconnect(sn)) != SOCK_OK) return ret;
50 #ifdef _LOOPBACK_DEBUG_
51          printf("%d:Socket Closed\r\n", sn);
52 #endif
53          break;
54       case SOCK_INIT :    //Initiate state
55 #ifdef _LOOPBACK_DEBUG_
56          printf("%d:Listen, TCP server loopback, port [%d]\r\n", sn, port);
57 #endif
58          if( (ret = listen(sn)) != SOCK_OK) return ret;
59          break;
60       case SOCK_CLOSED:    //Closed
61 #ifdef _LOOPBACK_DEBUG_
62          //printf("%d:TCP server loopback start\r\n",sn);
63 #endif
64          if((ret = socket(sn, Sn_MR_TCP, port, 0x00)) != sn) return ret;
65 #ifdef _LOOPBACK_DEBUG_
66          //printf("%d:Socket opened\r\n",sn);
67 #endif
68          break;
69       default:
70          break;
71    }
72    return 1;
73 }

 1 int32_t loopback_udps(uint8_t sn, uint8_t* buf, uint16_t port)
 2 {
 3    int32_t  ret;
 4    uint16_t size, sentsize;
 5    uint8_t  destip[4];
 6    uint16_t destport;
 7 
 8    switch(getSn_SR(sn))
 9    {
10       case SOCK_UDP :
11          if((size = getSn_RX_RSR(sn)) > 0)
12          {
13             if(size > DATA_BUF_SIZE) size = DATA_BUF_SIZE;
14             ret = recvfrom(sn, buf, size, destip, (uint16_t*)&destport);
15             if(ret <= 0)
16             {
17 #ifdef _LOOPBACK_DEBUG_
18                printf("%d: recvfrom error. %ld\r\n",sn,ret);
19 #endif
20                return ret;
21             }
22             size = (uint16_t) ret;
23             sentsize = 0;
24             while(sentsize != size)
25             {
26                ret = sendto(sn, buf+sentsize, size-sentsize, destip, destport);
27                if(ret < 0)
28                {
29 #ifdef _LOOPBACK_DEBUG_
30                   printf("%d: sendto error. %ld\r\n",sn,ret);
31 #endif
32                   return ret;
33                }
34                sentsize += ret; // Don\'t care SOCKERR_BUSY, because it is zero.
35             }
36          }
37          break;
38       case SOCK_CLOSED:
39 #ifdef _LOOPBACK_DEBUG_
40          //printf("%d:UDP loopback start\r\n",sn);
41 #endif
42          if((ret = socket(sn, Sn_MR_UDP, port, 0x00)) != sn)
43             return ret;
44 #ifdef _LOOPBACK_DEBUG_
45          printf("%d:Opened, UDP loopback, port [%d]\r\n", sn, port);
46 #endif
47          break;
48       default :
49          break;
50    }
51    return 1;
52 }