Function netbuf_ref

components/net/lwip/lwip-2.1.2/src/api/netbuf.c:150–166

* @ingroup netbuf * Let a netbuf reference existing (non-volatile) data. * * @param buf netbuf which should reference the data * @param dataptr pointer to the data to reference * @param size size of the data * @return ERR_OK if data is referenced * ERR_MEM if data couldn't be referenced due to lack of memory */

 *         ERR_MEM if data couldn't be referenced due to lack of memory
 */
err_t
netbuf_ref(struct netbuf *buf, const void *dataptr, u16_t size)
{
  LWIP_ERROR("netbuf_ref: invalid buf", (buf != NULL), return ERR_ARG;);
  if (buf->p != NULL) {
    pbuf_free(buf->p);
  }
  buf->p = pbuf_alloc(PBUF_TRANSPORT, 0, PBUF_REF);
  if (buf->p == NULL) {
    buf->ptr = NULL;
    return ERR_MEM;
  }
  ((struct pbuf_rom *)buf->p)->payload = dataptr;
  buf->p->len = buf->p->tot_len = size;
  buf->ptr = buf->p;
  return ERR_OK;
}

/**
 * @ingroup netbuf