113 lines
4.0 KiB
C
113 lines
4.0 KiB
C
/****************************************************************************
|
|
* libs/libnx/nxmu/nx_block.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 <errno.h>
|
|
#include <debug.h>
|
|
|
|
#include <nuttx/nx/nx.h>
|
|
#include <nuttx/nx/nxbe.h>
|
|
#include <nuttx/nx/nxmu.h>
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: nx_block
|
|
*
|
|
* Description:
|
|
* This is callback will do to things: (1) any queue a 'blocked' callback
|
|
* to the window and then (2) block any further window messaging.
|
|
*
|
|
* The 'blocked' callback is the response from nx_block (or nxtk_block).
|
|
* Those blocking interfaces are used to assure that no further messages
|
|
* are are directed to the window. Receipt of the blocked callback
|
|
* signifies that (1) there are no further pending callbacks and (2) that
|
|
* the window is now 'defunct' and will receive no further callbacks.
|
|
*
|
|
* This callback supports coordinated destruction of a window in multi-
|
|
* user mode. In multi-use mode, the client window logic must stay
|
|
* intact until all of the queued callbacks are processed. Then the
|
|
* window may be safely closed. Closing the window prior with pending
|
|
* callbacks can lead to bad behavior when the callback is executed.
|
|
*
|
|
* Input Parameters:
|
|
* wnd - The window to be blocked
|
|
* arg - An argument that will accompany the block messages (This is arg2
|
|
* in the blocked callback).
|
|
*
|
|
* Returned Value:
|
|
* OK on success; ERROR on failure with errno set appropriately
|
|
*
|
|
****************************************************************************/
|
|
|
|
int nx_block(NXWINDOW hwnd, FAR void *arg)
|
|
{
|
|
FAR struct nxbe_window_s *wnd = (FAR struct nxbe_window_s *)hwnd;
|
|
struct nxsvrmsg_blocked_s outmsg;
|
|
int ret = OK;
|
|
|
|
#ifdef CONFIG_DEBUG_FEATURES
|
|
if (!hwnd)
|
|
{
|
|
set_errno(EINVAL);
|
|
return ERROR;
|
|
}
|
|
#endif
|
|
|
|
/* Ignore additional attempts to block messages (no errors reported) */
|
|
|
|
if (!NXBE_ISBLOCKED(wnd))
|
|
{
|
|
/* Mark the window as blocked. This will stop all messages to the
|
|
* window (EXCEPT the NX_SVRMSG_BLOCKED).
|
|
* Blocking the messages before sending the blocked message
|
|
* is awkward but assures that no other messages sneak into
|
|
* the message queue before we can set the blocked state.
|
|
*/
|
|
|
|
NXBE_SETBLOCKED(wnd);
|
|
|
|
/* Send the message indicating that the window is blocked
|
|
* (and because of queue also that there are no additional queue
|
|
* messages for the window)
|
|
*/
|
|
|
|
outmsg.msgid = NX_SVRMSG_BLOCKED;
|
|
outmsg.wnd = wnd;
|
|
outmsg.arg = arg;
|
|
|
|
/* Send the window message via nxmu_sendserver (vs. nxmu_sendwindow) so
|
|
* that it will not be blocked.
|
|
*/
|
|
|
|
ret = nxmu_sendserver(wnd->conn, &outmsg,
|
|
sizeof(struct nxsvrmsg_blocked_s));
|
|
}
|
|
|
|
return ret;
|
|
}
|