incubator-nuttx/sched/task/task_setcancelstate.c

140 lines
4.2 KiB
C

/****************************************************************************
* sched/task/task_setcancelstate.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 <pthread.h>
#include <sched.h>
#include <errno.h>
#include "sched/sched.h"
#include "task/task.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: task_setcancelstate
*
* Description:
* The task_setcancelstate() function atomically both sets the calling
* task's cancellability state to the indicated state and returns the
* previous cancellability state at the location referenced by oldstate.
* Legal values for state are TASK_CANCEL_ENABLE and TASK_CANCEL_DISABLE.
*
* The cancellability state and type of any newly created tasks are
* TASK_CANCEL_ENABLE and TASK_CANCEL_DEFERRED respectively.
*
* Input Parameters:
* state - the new cancellability state, either TASK_CANCEL_ENABLE or
* TASK_CANCEL_DISABLE
* oldstate - The location to return the old cancellability state.
*
* Returned Value:
* Zero (OK) on success; ERROR is returned on any failure with the
* errno value set appropriately.
*
****************************************************************************/
int task_setcancelstate(int state, FAR int *oldstate)
{
FAR struct tcb_s *tcb = this_task();
int ret = OK;
/* Suppress context changes for a bit so that the flags are stable. (the
* flags should not change in interrupt handling).
*/
sched_lock();
/* Return the current state if so requested */
if (oldstate != NULL)
{
if ((tcb->flags & TCB_FLAG_NONCANCELABLE) != 0)
{
*oldstate = TASK_CANCEL_DISABLE;
}
else
{
*oldstate = TASK_CANCEL_ENABLE;
}
}
/* Set the new cancellation state */
if (state == TASK_CANCEL_ENABLE)
{
/* Clear the non-cancelable flag */
tcb->flags &= ~TCB_FLAG_NONCANCELABLE;
/* Check if a cancellation was pending */
if ((tcb->flags & TCB_FLAG_CANCEL_PENDING) != 0)
{
#ifdef CONFIG_CANCELLATION_POINTS
/* If we are using deferred cancellation? */
if ((tcb->flags & TCB_FLAG_CANCEL_DEFERRED) == 0)
#endif
{
/* No.. We are using asynchronous cancellation. If the
* cancellation was pending in this case, then just exit.
*/
tcb->flags &= ~TCB_FLAG_CANCEL_PENDING;
#ifndef CONFIG_DISABLE_PTHREAD
if ((tcb->flags & TCB_FLAG_TTYPE_MASK) ==
TCB_FLAG_TTYPE_PTHREAD)
{
pthread_exit(PTHREAD_CANCELED);
}
else
#endif
{
_exit(EXIT_FAILURE);
}
}
}
}
else if (state == TASK_CANCEL_DISABLE)
{
/* Set the non-cancelable state */
tcb->flags |= TCB_FLAG_NONCANCELABLE;
}
else
{
set_errno(EINVAL);
ret = ERROR;
}
sched_unlock();
return ret;
}