Function at_recvfrom

components/net/at/at_socket/at_socket.c:1004–1121

#endif

int at_recvfrom(int socket, void *mem, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen)
{
    struct at_socket *sock = RT_NULL;
    int timeout, result = 0;
    size_t recv_len = 0;

    if (mem == RT_NULL || len == 0)
    {
        /* if the requested number of bytes to receive from a stream socket was 0. */
        rt_set_errno(EFAULT);
        return -1;
    }

    sock = at_get_socket(socket);
    if (sock == RT_NULL)
    {
        rt_set_errno(ENXIO);
        return -1;
    }

    /* if the socket type is UDP, need to connect socket first */
    if (sock->type == AT_SOCKET_UDP)
    {
        if (from == RT_NULL || fromlen == 0)
        {
            rt_set_errno(EFAULT);
            return -1;
        }

        if(sock->state == AT_SOCKET_CONNECT && rt_memcmp(&sock->last_udp_adr, from, sizeof(struct sockaddr)) != 0)
        {
            if (sock->ops->at_closesocket(sock) != 0)
            {
                free_socket(sock);
                rt_set_errno(EIO);
                goto __exit;
            }
            sock->state = AT_SOCKET_OPEN;
        }

        if (sock->state == AT_SOCKET_OPEN)
        {
            ip_addr_t remote_addr;
            uint16_t remote_port = 0;
            char ipstr[16] = { 0 };

            socketaddr_to_ipaddr_port(from, &remote_addr, &remote_port);
            ipaddr_to_ipstr(from, ipstr);

            if (sock->ops->at_connect(sock, ipstr, remote_port, sock->type, RT_TRUE) < 0)
            {
                at_do_event_changes(sock, AT_EVENT_ERROR, RT_TRUE);
                rt_set_errno(EIO);
                /* socket shutdown */
                goto __exit;
            }

            rt_memcpy(&sock->last_udp_adr, from, sizeof(struct sockaddr));