nuttx/libs/libnx/nxmu/nx_constructwindow.c

/****************************************************************************
 * libs/libnx/nxmu/nx_constsructwindow.c
 *
 *   Copyright (C) 2008, 2011-2013, 2019 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * 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 <errno.h>
#include <debug.h>

#include <nuttx/nx/nx.h>
#include <nuttx/nx/nxbe.h>
#include <nuttx/nx/nxmu.h>

#include "nxcontext.h"

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

/****************************************************************************
 * Name: nx_constructwindow
 *
 * Description:
 *   This function is the same a nx_openwindow EXCEPT that the client provides
 *   the window structure instance.  nx_constructwindow will initialize the
 *   the pre-allocated window structure for use by NX.  This function is
 *   provided in addition to nx_openwindow in order to support a kind of
 *   inheritance:  The caller's window structure may include extensions that
 *   are not visible to NX.
 *
 *   NOTE:  hwnd must have been allocated using a user-space allocator that
 *   permits user access to the window.  Once provided to nx_constructwindow()
 *   that memory is owned and managed by NX.  On certain error conditions or
 *   when the window is closed, NX will free the window.
 *
 * Input Parameters:
 *   handle - The handle returned by nx_connect
 *   hwnd   - The pre-allocated window structure.
 *   flags  - Optional flags.  Must be zero unless CONFIG_NX_RAMBACKED is
 *            enabled.  In that case, it may be zero or
 *            NXBE_WINDOW_RAMBACKED
 *   cb     - Callbacks used to process window events
 *   arg    - User provided value that will be returned with NX callbacks.
 *
 * Returned Value:
 *   OK on success; ERROR on failure with errno set appropriately.  In the
 *   case of ERROR, NX will have deallocated the pre-allocated window.
 *
 ****************************************************************************/

int nx_constructwindow(NXHANDLE handle, NXWINDOW hwnd, uint8_t flags,
                       FAR const struct nx_callback_s *cb, FAR void *arg)
{
  FAR struct nxmu_conn_s *conn = (FAR struct nxmu_conn_s *)handle;
  FAR struct nxbe_window_s *wnd = (FAR struct nxbe_window_s *)hwnd;
  struct nxsvrmsg_openwindow_s outmsg;

#ifdef CONFIG_DEBUG_FEATURES
  if (wnd == NULL)
    {
      set_errno(EINVAL);
      return ERROR;
    }

  if (conn == NULL || cb == NULL || (flags & ~NXBE_WINDOW_USER) != 0)
    {
      lib_ufree(wnd);
      set_errno(EINVAL);
      return ERROR;
    }
#endif

  /* Setup only the connection structure, user flags, callbacks and client
   * private data reference. The server will set everything else up.
   */

  wnd->conn   = conn;
  wnd->flags  = flags;
  wnd->cb     = cb;
  wnd->arg    = arg;
#ifdef CONFIG_NX_RAMBACKED
#ifdef CONFIG_BUILD_KERNEL
  wnd->npages = 0;
#endif
  wnd->stride = 0;
  wnd->fbmem  = NULL;
#endif

  /* Request initialization the new window from the server */

  outmsg.msgid = NX_SVRMSG_OPENWINDOW;
  outmsg.wnd   = wnd;

  return nxmu_sendserver(conn, &outmsg, sizeof(struct nxsvrmsg_openwindow_s));
}