Niobe开发板UDP联网演示

struct sockaddr_in {
	sa_family_t sin_family;
	in_port_t sin_port;
	struct in_addr sin_addr;
	uint8_t sin_zero[8];
};

	//服务端地址信息
	struct sockaddr_in server_sock;
	bzero(&server_sock, sizeof(server_sock));
	server_sock.sin_family = AF_INET;
	//server_sock.sin_addr.s_addr = htonl(INADDR_ANY);
	inet_pton(AF_INET, _SERVER_IP_, &server_sock.sin_addr); 
	server_sock.sin_port = htons(_PROT_);

typedef struct {
	unsigned long fds_bits[FD_SETSIZE / 8 / sizeof(long)];
} fd_set;

	fd_set fds;
	FD_ZERO(&fds);
    FD_SET(sock_fd,&fds);//将sock_fd添加至fds

    if(FD_ISSET(sock_fd,&fds))//判断sock_fd是否在fds中
        ;//

struct sockaddr {
	sa_family_t sa_family;
	char sa_data[14];
};

int WifiConnect(const char *ssid, const char *psk)

int socket(int domain, int type, int protocol)

int bind(int fd, const struct sockaddr *addr, socklen_t len)

ssize_t recvfrom(int fd, void *restrict buf, size_t len, int flags, struct sockaddr *restrict addr, socklen_t *restrict alen)

ssize_t sendto(int fd, const void *buf, size_t len, int flags, const struct sockaddr *addr, socklen_t alen)

int select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout)

static void UDPServerTaskWithSelect(void)
{
	//服务端地址信息
	struct sockaddr_in server_sock;
	
	int sin_size = sizeof(struct sockaddr_in);
	//连接Wifi
	if(WifiConnect(WIFI_SSID,WIFI_PASSWORD)!=0)
	{
		perror("Wifi connect error!");
		exit(1);
	}
	//in_addr_t localIpaddr = GetLocalIpaddr();
	uint32_t localIpaddr = htonl(GetLocalIpaddr());
	char strr[IP_LEN];
	inet_ntop(AF_INET, &server_sock.sin_addr, strr, sizeof(strr));
	printf("GetLocalIpaddr is %s \n",strr);

	//创建socket
	printf("socket begin\n");
	int sock_fd=-1;
	if ((sock_fd = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
	{
		perror("socket is error\r\n");
		exit(1);
	}
	printf("sock_fd=%d\n",sock_fd);

	bzero(&server_sock, sizeof(server_sock));
	server_sock.sin_family = AF_INET;
	//server_sock.sin_addr.s_addr = htonl(INADDR_ANY);
	inet_pton(AF_INET, _SERVER_IP_, &server_sock.sin_addr); //inet_addr("127.0.0.1");
	server_sock.sin_port = htons(_PROT_);
	char str[IP_LEN];
	inet_ntop(AF_INET, &server_sock.sin_addr, str, sizeof(str));
	printf("udp server IP_addr: %s at PORT %d\n",str,ntohs(server_sock.sin_port));
	
	//调用bind函数绑定socket和地址
	if (bind(sock_fd, (struct sockaddr *)&server_sock, sizeof(struct sockaddr)) == -1)
	{
		perror("bind is error\r\n");
		exit(1);
	}
	
	//printf("start select\r\n");
	fd_set fds;
	FD_ZERO(&fds);	

	while(true)
	{		
		printf("select wait...\n");
		FD_SET(sock_fd,&fds);
        int ret = select(sock_fd + 1, &fds, NULL, NULL, NULL);
		if(ret<=0)
		{
			//超时等
			printf("[DISCOVERY]ret:%d\n", ret);
			continue;
		}
		//printf("select\n");
		if(FD_ISSET(sock_fd,&fds))
		{
			//客户端地址信息
			struct sockaddr_in repaddr;
			memset(recvbuf,0,sizeof(recvbuf));
			memset(&repaddr, 0, sizeof(struct sockaddr));
			int res = recvfrom(sock_fd, recvbuf, sizeof(recvbuf)-1, 0, (struct sockaddr *)&repaddr, (socklen_t *)&sin_size);
			//"exit"特殊字符串，表示客户端申请断开链接
			if(strlen(recvbuf)==4 && memcmp(recvbuf,"exit",5)==0)
			{
				printf("remote client close,msg is %s\n",recvbuf);
				sendto(sock_fd, "exit", strlen("exit") + 1, 0, (struct sockaddr *)&repaddr, (socklen_t)sin_size);
			}
			else
			{
				printf("recv msg :%s\n",recvbuf);
				if (sendto(sock_fd, udpSendBuf, strlen(udpSendBuf) + 1, 0, (struct sockaddr *)&repaddr, (socklen_t)sin_size) == -1)
				{
					perror("send error \r\n");
				}
				else{ printf("send msg %s \n",udpSendBuf);}
			}
			osDelay(10);
			FD_ZERO(&fds);
		}
	}	
	close(sock_fd);
	FD_CLR(sock_fd,&fds);
	sock_fd=-1;
	return ;
}

// 默认WiFi名和密码
#define WIFI_SSID "aaa"
#define WIFI_PASSWORD "talkweb1996"

// 默认服务端的ip地址和端口号
#define _PROT_ 8800
#define _SERVER_IP_ "192.168.1.114"

        # "TW303_Network_mqttclient:network_mqttclient_example",
        # "TW402_APP_oled_u8g2:app_oled_u8g2_example",
        # "TW304_Network_tcpserver:network_tcpserver_demo",
        # "TW304_Network_tcpclient:network_tcpclient_demo",
        # "TW305_Network_udpclient:network_udpclient_demo",
		 "TW305_Network_udpserver:network_udpserver_demo",

callback function for wifi connect

WaitConnectResult:wait success[1]s
WiFi connect succeed!
begain to dhcp<-- DHCP state:Inprogress -->

<-- DHCP state:OK -->
server :
	server_id : 192.168.1.1
	mask : 255.255.255.0, 1
	gw : 192.168.1.1
	T0 : 7200
	T1 : 3600
	T2 : 6300
clients <1> :
	mac_idx mac             addr            state   lease   tries   rto     
	0       849dc22100d4    192.168.1.112   10      0       1       4     

tcp server IP_addr: 192.168.1.112 at PORT 8800
select wait...

recv msg :0000
send msg Hello! I'm Talkweb UDP Server! 

select wait...

recv msg :1111
send msg Hello! I'm Talkweb UDP Server! 

select wait...

recv msg :2222
send msg Hello! I'm Talkweb UDP Server! 

select wait...

remote client close,msg is exit

select wait...