Function lwip_accept

components/net/lwip/lwip-1.4.1/src/api/sockets.c:323–415

 */

int
lwip_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
{
  struct lwip_sock *sock, *nsock;
  struct netconn *newconn;
  ip_addr_t naddr;
  u16_t port;
  int newsock;
  struct sockaddr_in sin;
  err_t err;
  SYS_ARCH_DECL_PROTECT(lev);

  LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d)...\n", s));
  sock = get_socket(s);
  if (!sock) {
    return -1;
  }

  if (netconn_is_nonblocking(sock->conn) && (sock->rcvevent <= 0)) {
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d): returning EWOULDBLOCK\n", s));
    sock_set_errno(sock, EWOULDBLOCK);
    return -1;
  }

  /* wait for a new connection */
  err = netconn_accept(sock->conn, &newconn);
  if (err != ERR_OK) {
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d): netconn_acept failed, err=%d\n", s, err));
    if (netconn_type(sock->conn) != NETCONN_TCP) {
      sock_set_errno(sock, EOPNOTSUPP);
      return EOPNOTSUPP;
    }
    sock_set_errno(sock, err_to_errno(err));
    return -1;
  }
  LWIP_ASSERT("newconn != NULL", newconn != NULL);
  /* Prevent automatic window updates, we do this on our own! */
  netconn_set_noautorecved(newconn, 1);

  /* get the IP address and port of the remote host */
  err = netconn_peer(newconn, &naddr, &port);
  if (err != ERR_OK) {
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d): netconn_peer failed, err=%d\n", s, err));
    netconn_delete(newconn);
    sock_set_errno(sock, err_to_errno(err));
    return -1;
  }

  /* Note that POSIX only requires us to check addr is non-NULL. addrlen must
   * not be NULL if addr is valid.
   */
  if (NULL != addr) {
    LWIP_ASSERT("addr valid but addrlen NULL", addrlen != NULL);
    memset(&sin, 0, sizeof(sin));
    sin.sin_len = sizeof(sin);
    sin.sin_family = AF_INET;
    sin.sin_port = htons(port);
    inet_addr_from_ipaddr(&sin.sin_addr, &naddr);