api_lib.c

lwip-1.4.0

#endif /* LWIP_SO_RCVTIMEO*/

#if LWIP_TCP
  if (conn->type == NETCONN_TCP) {
    if (!netconn_get_noautorecved(conn) || (buf == NULL)) {
      /* Let the stack know that we have taken the data. */
      /* TODO: Speedup: Don't block and wait for the answer here
         (to prevent multiple thread-switches). */
      msg.function = do_recv;
      msg.msg.conn = conn;
      if (buf != NULL) {
        msg.msg.msg.r.len = ((struct pbuf *)buf)->tot_len;
      } else {
        msg.msg.msg.r.len = 1;
      }
      /* don't care for the return value of do_recv */
      TCPIP_APIMSG(&msg);
    }

    /* If we are closed, we indicate that we no longer wish to use the socket */
    if (buf == NULL) {
      API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
      /* Avoid to lose any previous error code */
      NETCONN_SET_SAFE_ERR(conn, ERR_CLSD);
      return ERR_CLSD;
    }
    len = ((struct pbuf *)buf)->tot_len;
  }
#endif /* LWIP_TCP */
#if LWIP_TCP && (LWIP_UDP || LWIP_RAW)
  else
#endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
#if (LWIP_UDP || LWIP_RAW)
  {
    LWIP_ASSERT("buf != NULL", buf != NULL);
    len = netbuf_len((struct netbuf *)buf);
  }
#endif /* (LWIP_UDP || LWIP_RAW) */

#if LWIP_SO_RCVBUF
  SYS_ARCH_DEC(conn->recv_avail, len);
#endif /* LWIP_SO_RCVBUF */
  /* Register event with callback */
  API_EVENT(conn, NETCONN_EVT_RCVMINUS, len);

  LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_recv_data: received %p, len=%"U16_F"\n", buf, len));

  *new_buf = buf;
  /* don't set conn->last_err: it's only ERR_OK, anyway */
  return ERR_OK;
}

/**
 * Receive data (in form of a pbuf) from a TCP netconn
 *
 * @param conn the netconn from which to receive data
 * @param new_buf pointer where a new pbuf is stored when received data
 * @return ERR_OK if data has been received, an error code otherwise (timeout,
 *                memory error or another error)
 *         ERR_ARG if conn is not a TCP netconn
 */
err_t
netconn_recv_tcp_pbuf(struct netconn *conn, struct pbuf **new_buf)
{
  LWIP_ERROR("netconn_recv: invalid conn", (conn != NULL) &&
             netconn_type(conn) == NETCONN_TCP, return ERR_ARG;);

  return netconn_recv_data(conn, (void **)new_buf);
}

/**
 * Receive data (in form of a netbuf containing a packet buffer) from a netconn
 *
 * @param conn the netconn from which to receive data
 * @param new_buf pointer where a new netbuf is stored when received data
 * @return ERR_OK if data has been received, an error code otherwise (timeout,
 *                memory error or another error)
 */
err_t
netconn_recv(struct netconn *conn, struct netbuf **new_buf)
{
#if LWIP_TCP
  struct netbuf *buf = NULL;
  err_t err;
#endif /* LWIP_TCP */

  LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
  *new_buf = NULL;
  LWIP_ERROR("netconn_recv: invalid conn",    (conn != NULL),    return ERR_ARG;);
  LWIP_ERROR("netconn_accept: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);

#if LWIP_TCP
  if (conn->type == NETCONN_TCP) {
    struct pbuf *p = NULL;
    /* This is not a listening netconn, since recvmbox is set */

    buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
    if (buf == NULL) {
      NETCONN_SET_SAFE_ERR(conn, ERR_MEM);
      return ERR_MEM;
    }

    err = netconn_recv_data(conn, (void **)&p);
    if (err != ERR_OK) {
      memp_free(MEMP_NETBUF, buf);
      return err;
    }
    LWIP_ASSERT("p != NULL", p != NULL);

    buf->p = p;
    buf->ptr = p;
    buf->port = 0;
    ip_addr_set_any(&buf->addr);
    *new_buf = buf;
    /* don't set conn->last_err: it's only ERR_OK, anyway */
    return ERR_OK;
  } else
#endif /* LWIP_TCP */
  {
#if (LWIP_UDP || LWIP_RAW)
    return netconn_recv_data(conn, (void **)new_buf);
#endif /* (LWIP_UDP || LWIP_RAW) */
  }
}

/**
 * TCP: update the receive window: by calling this, the application
 * tells the stack that it has processed data and is able to accept
 * new data.
 * ATTENTION: use with care, this is mainly used for sockets!
 * Can only be used when calling netconn_set_noautorecved(conn, 1) before.
 *
 * @param conn the netconn for which to update the receive window
 * @param length amount of data processed (ATTENTION: this must be accurate!)
 */
void
netconn_recved(struct netconn *conn, u32_t length)
{
#if LWIP_TCP
  if ((conn != NULL) && (conn->type == NETCONN_TCP) &&
      (netconn_get_noautorecved(conn))) {
    struct api_msg msg;
    /* Let the stack know that we have taken the data. */
    /* TODO: Speedup: Don't block and wait for the answer here
       (to prevent multiple thread-switches). */
    msg.function = do_recv;
    msg.msg.conn = conn;
    msg.msg.msg.r.len = length;
    /* don't care for the return value of do_recv */
    TCPIP_APIMSG(&msg);
  }
#else /* LWIP_TCP */
  LWIP_UNUSED_ARG(conn);
  LWIP_UNUSED_ARG(length);
#endif /* LWIP_TCP */
}

/**
 * Send data (in form of a netbuf) to a specific remote IP address and port.
 * Only to be used for UDP and RAW netconns (not TCP).
 *
 * @param conn the netconn over which to send data
 * @param buf a netbuf containing the data to send
 * @param addr the remote IP address to which to send the data
 * @param port the remote port to which to send the data
 * @return ERR_OK if data was sent, any other err_t on error
 */
err_t
netconn_sendto(struct netconn *conn, struct netbuf *buf, ip_addr_t *addr, u16_t port)
{
  if (buf != NULL) {
    ip_addr_set(&buf->addr, addr);
    buf->port = port;
    return netconn_send(conn, buf);
  }
  return ERR_VAL;
}

/**
 * Send data over a UDP or RAW netconn (that is already connected).
 *
 * @param conn the UDP or RAW netconn over which to send data
 * @param buf a netbuf containing the data to send
 * @return ERR_OK if data was sent, any other err_t on error
 */
err_t
netconn_send(struct netconn *conn, struct netbuf *buf)
{
  struct api_msg msg;
  err_t err;

  LWIP_ERROR("netconn_send: invalid conn",  (conn != NULL), return ERR_ARG;);

  LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_send: sending %"U16_F" bytes\n", buf->p->tot_len));
  msg.function = do_send;
  msg.msg.conn = conn;
  msg.msg.msg.b = buf;
  err = TCPIP_APIMSG(&msg);

  NETCONN_SET_SAFE_ERR(conn, err);
  return err;
}

/**
 * Send data over a TCP netconn.
 *
 * @param conn the TCP netconn over which to send data
 * @param dataptr pointer to the application buffer that contains the data to send
 * @param size size of the application data to send
 * @param apiflags combination of following flags :
 * - NETCONN_COPY: data will be copied into memory belonging to the stack
 * - NETCONN_MORE: for TCP connection, PSH flag will be set on last segment sent
 * - NETCONN_DONTBLOCK: only write the data if all dat can be written at once
 * @return ERR_OK if data was sent, any other err_t on error
 */
err_t
netconn_write(struct netconn *conn, const void *dataptr, size_t size, u8_t apiflags)
{
  struct api_msg msg;
  err_t err;

  LWIP_ERROR("netconn_write: invalid conn",  (conn != NULL), return ERR_ARG;);
  LWIP_ERROR("netconn_write: invalid conn->type",  (conn->type == NETCONN_TCP), return ERR_VAL;);
  if (size == 0) {
    return ERR_OK;
  }

  /* @todo: for non-blocking write, check if 'size' would ever fit into
            snd_queue or snd_buf */
  msg.function = do_write;
  msg.msg.conn = conn;
  msg.msg.msg.w.dataptr = dataptr;
  msg.msg.msg.w.apiflags = apiflags;
  msg.msg.msg.w.len = size;
  /* For locking the core: this _can_ be delayed on low memory/low send buffer,
     but if it is, this is done inside api_msg.c:do_write(), so we can use the
     non-blocking version here. */
  err = TCPIP_APIMSG(&msg);

  NETCONN_SET_SAFE_ERR(conn, err);
  return err;
}

/**
 * Close ot shutdown a TCP netconn (doesn't delete it).
 *
 * @param conn the TCP netconn to close or shutdown
 * @param how fully close or only shutdown one side?
 * @return ERR_OK if the netconn was closed, any other err_t on error
 */
static err_t
netconn_close_shutdown(struct netconn *conn, u8_t how)
{
  struct api_msg msg;
  err_t err;

  LWIP_ERROR("netconn_close: invalid conn",  (conn != NULL), return ERR_ARG;);

  msg.function = do_close;
  msg.msg.conn = conn;
  /* shutting down both ends is the same as closing */
  msg.msg.msg.sd.shut = how;
  /* because of the LWIP_TCPIP_CORE_LOCKING implementation of do_close,
     don't use TCPIP_APIMSG here */
  err = tcpip_apimsg(&msg);

  NETCONN_SET_SAFE_ERR(conn, err);
  return err;
}

/**
 * Close a TCP netconn (doesn't delete it).
 *
 * @param conn the TCP netconn to close
 * @return ERR_OK if the netconn was closed, any other err_t on error
 */
err_t
netconn_close(struct netconn *conn)
{
  /* shutting down both ends is the same as closing */
  return netconn_close_shutdown(conn, NETCONN_SHUT_RDWR);
}

/**
 * Shut down one or both sides of a TCP netconn (doesn't delete it).
 *
 * @param conn the TCP netconn to shut down
 * @return ERR_OK if the netconn was closed, any other err_t on error
 */
err_t
netconn_shutdown(struct netconn *conn, u8_t shut_rx, u8_t shut_tx)
{
  return netconn_close_shutdown(conn, (shut_rx ? NETCONN_SHUT_RD : 0) | (shut_tx ? NETCONN_SHUT_WR : 0));
}

#if LWIP_IGMP
/**
 * Join multicast groups for UDP netconns.
 *
 * @param conn the UDP netconn for which to change multicast addresses
 * @param multiaddr IP address of the multicast group to join or leave
 * @param netif_addr the IP address of the network interface on which to send
 *                  the igmp message
 * @param join_or_leave flag whether to send a join- or leave-message
 * @return ERR_OK if the action was taken, any err_t on error
 */
err_t
netconn_join_leave_group(struct netconn *conn,
                         ip_addr_t *multiaddr,
                         ip_addr_t *netif_addr,
                         enum netconn_igmp join_or_leave)
{
  struct api_msg msg;
  err_t err;

  LWIP_ERROR("netconn_join_leave_group: invalid conn",  (conn != NULL), return ERR_ARG;);

  msg.function = do_join_leave_group;
  msg.msg.conn = conn;
  msg.msg.msg.jl.multiaddr = multiaddr;
  msg.msg.msg.jl.netif_addr = netif_addr;
  msg.msg.msg.jl.join_or_leave = join_or_leave;
  err = TCPIP_APIMSG(&msg);

  NETCONN_SET_SAFE_ERR(conn, err);
  return err;
}
#endif /* LWIP_IGMP */

#if LWIP_DNS
/**
 * Execute a DNS query, only one IP address is returned
 *
 * @param name a string representation of the DNS host name to query
 * @param addr a preallocated ip_addr_t where to store the resolved IP address
 * @return ERR_OK: resolving succeeded
 *         ERR_MEM: memory error, try again later
 *         ERR_ARG: dns client not initialized or invalid hostname
 *         ERR_VAL: dns server response was invalid
 */
err_t
netconn_gethostbyname(const char *name, ip_addr_t *addr)
{
  struct dns_api_msg msg;
  err_t err;
  sys_sem_t sem;

  LWIP_ERROR("netconn_gethostbyname: invalid name", (name != NULL), return ERR_ARG;);
  LWIP_ERROR("netconn_gethostbyname: invalid addr", (addr != NULL), return ERR_ARG;);

  err = sys_sem_new(&sem, 0);
  if (err != ERR_OK) {
    return err;
  }

  msg.name = name;
  msg.addr = addr;
  msg.err = &err;
  msg.sem = &sem;

  tcpip_callback(do_gethostbyname, &msg);
  sys_sem_wait(&sem);
  sys_sem_free(&sem);

  return err;
}
#endif /* LWIP_DNS*/

#endif /* LWIP_NETCONN */