nuttx/graphics/nxbe/nxbe_closewindow.c

/****************************************************************************
 * graphics/nxbe/nxbe_closewindow.c
 *
 *   Copyright (C) 2008-2009 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <stdlib.h>
#include <assert.h>
#include <debug.h>

#include <nuttx/nxglib.h>
#include "nxbe.h"

/****************************************************************************
 * Pre-Processor Definitions
 ****************************************************************************/

/****************************************************************************
 * Private Types
 ****************************************************************************/

/****************************************************************************
 * Private Data
 ****************************************************************************/

/****************************************************************************
 * Public Data
 ****************************************************************************/

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: nxbe_closewindow
 *
 * Description:
 *   Close an existing window
 *
 * Input Parameters:
 *   wnd  - The window to be closed (and deallocated)
 *
 * Return:
 *   None
 *
 ****************************************************************************/

void nxbe_closewindow(struct nxbe_window_s *wnd)
{
  FAR struct nxbe_state_s *be = wnd->be;
#ifdef CONFIG_DEBUG
  if (!wnd)
    {
      return;
    }

  /* The background window should never be closed */

  DEBUGASSERT(wnd != &be->bkgd);
#endif

  /* Is there a window above the one being closed? */

  if (wnd->above)
    {
      /* Yes, now the window below that on is the window below
       * the one being closed.
       */

      wnd->above->below = wnd->below;
    }
  else
    {
      /* No, then the top window is the one below this (which
       * can never be NULL because the background window is
       * always at the true bottom of the list
       */

      be->topwnd = wnd->below;
    }

  /* There is always a window below the one being closed (because
   * the background is never closed.  Now, the window above that
   * is the window above the one that is being closed.
   */

  wnd->below->above = wnd->above;
  free(wnd);
}