* libs/libc/wqueue/work_queue.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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 <stdint.h>
#include <signal.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/clock.h>
#include <nuttx/list.h>
#include <nuttx/wqueue.h>
#include "wqueue/wqueue.h"
#if defined(CONFIG_LIBC_USRWORK) && !defined(__KERNEL__)
* Private Functions
****************************************************************************/
* Name: work_qqueue
*
* Description:
* Queue work to be performed at a later time. All queued work will be
* performed on the worker thread of execution (not the caller's).
*
* The work structure is allocated by caller, but completely managed by
* the work queue logic. The caller should never modify the contents of
* the work queue structure; the caller should not call work_qqueue()
* again until either (1) the previous work has been performed and removed
* from the queue, or (2) work_cancel() has been called to cancel the work
* and remove it from the work queue.
*
* Input Parameters:
* wqueue - The work queue
* work - The work structure to queue
* worker - The worker callback to be invoked. The callback will be
* invoked on the worker thread of execution.
* arg - The argument that will be passed to the worker callback when
* int is invoked.
* delay - Delay (in clock ticks) from the time queue until the worker
* is invoked. Zero means to perform the work immediately.
*
* Returned Value:
* Zero on success, a negated errno on failure
*
****************************************************************************/
static int work_qqueue(FAR struct usr_wqueue_s *wqueue,
FAR struct work_s *work, worker_t worker,
FAR void *arg, clock_t delay)
{
FAR struct work_s *curr;
FAR struct work_s *head;
int semcount;
while (nxmutex_lock(&wqueue->lock) < 0);
work->worker = worker;
work->arg = arg;
work->qtime = clock() + delay;
head = list_first_entry(&wqueue->q, struct work_s, node);
list_for_every_entry(&wqueue->q, curr, struct work_s, node)
{
if (!clock_compare(curr->qtime, work->qtime))
{
break;
}
}
* the wait queue is sorted by the expired time. Because
* curr->qtime > work->qtime.
* In the case of the wqueue is empty, we insert
* the work at the head of the wait queue.
*/
list_add_before(&curr->node, &work->node);
* We should wake up the worker thread.
*/
if (curr == head)
{
nxsem_get_value(&wqueue->wake, &semcount);
if (semcount < 1)
{
nxsem_post(&wqueue->wake);
}
}
nxmutex_unlock(&wqueue->lock);
return OK;
}
* Public Functions
****************************************************************************/
* Name: work_queue
*
* Description:
* Queue user-mode work to be performed at a later time. All queued work
* will be performed on the worker thread of execution (not the caller's).
*
* The work structure is allocated and must be initialized to all zero by
* the caller. Otherwise, the work structure is completely managed by the
* work queue logic. The caller should never modify the contents of the
* work queue structure directly. If work_queue() is called before the
* previous work has been performed and removed from the queue, then any
* pending work will be canceled and lost.
*
* Input Parameters:
* qid - The work queue ID (index)
* work - The work structure to queue
* worker - The worker callback to be invoked. The callback will be
* invoked on the worker thread of execution.
* arg - The argument that will be passed to the worker callback when
* int is invoked.
* delay - Delay (in clock ticks) from the time queue until the worker
* is invoked. Zero means to perform the work immediately.
*
* Returned Value:
* Zero on success, a negated errno on failure
*
****************************************************************************/
int work_queue(int qid, FAR struct work_s *work, worker_t worker,
FAR void *arg, clock_t delay)
{
if (qid == USRWORK)
{
work_cancel(qid, work);
return work_qqueue(&g_usrwork, work, worker, arg, delay);
}
else
{
return -EINVAL;
}
}
#endif