incubator-nuttx/libs/libnx/nxmu/nx_constructwindow.c

119 lines
4.1 KiB
C

/****************************************************************************
* libs/libnx/nxmu/nx_constructwindow.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* 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));
}