rt-thread/examples/network/udpserver.c

#include <rtthread.h>
#include <lwip/sockets.h>

void udpserv(void* paramemter)
{
	int sock;
	int bytes_read;
	char *recv_data;
	rt_uint32_t addr_len;
	struct sockaddr_in server_addr , client_addr;

    recv_data = rt_malloc(1024);
    if (recv_data == RT_NULL)
    {
        rt_kprintf("No memory\n");
        return;
    }

    /* create socket */
	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
	{
		rt_kprintf("Socket error\n");

        /* release recv buffer */
        rt_free(recv_data);
		return;
	}

    /* init server socket address */
	server_addr.sin_family = AF_INET;
	server_addr.sin_port = htons(5000);
	server_addr.sin_addr.s_addr = INADDR_ANY;
	rt_memset(&(server_addr.sin_zero),0, sizeof(server_addr.sin_zero));

	if (bind(sock,(struct sockaddr *)&server_addr,
			 sizeof(struct sockaddr)) == -1)
	{
		rt_kprintf("Bind error\n");

        /* release recv buffer */
        rt_free(recv_data);
        return;
	}

	addr_len = sizeof(struct sockaddr);

	rt_kprintf("UDPServer Waiting for client on port 5000...\n");

	while (1)
	{
		bytes_read = recvfrom(sock, recv_data, 1024, 0,
            (struct sockaddr *)&client_addr, &addr_len);
		recv_data[bytes_read] = '\0';
		rt_kprintf("\n(%s , %d) said : ",inet_ntoa(client_addr.sin_addr),
			   ntohs(client_addr.sin_port));
		rt_kprintf("%s", recv_data);

        if (strcmp(recv_data, "exit") == 0)
        {
            lwip_close(sock);

            /* release recv buffer */
            rt_free(recv_data);
            break;
        }
	}

	return;
}

#ifdef RT_USING_FINSH
#include <finsh.h>
FINSH_FUNCTION_EXPORT(udpserv, startup udp server);
#endif