149 lines
5.1 KiB
C
149 lines
5.1 KiB
C
/**************************************************************************
|
|
* sched/pthread_cancel.c
|
|
*
|
|
* Copyright (C) 2007, 2009 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 <sys/types.h>
|
|
#include <unistd.h>
|
|
#include <pthread.h>
|
|
#include <errno.h>
|
|
|
|
#include "os_internal.h"
|
|
#include "pthread_internal.h"
|
|
|
|
/**************************************************************************
|
|
* Private Definitions
|
|
**************************************************************************/
|
|
|
|
/**************************************************************************
|
|
* Private Types
|
|
**************************************************************************/
|
|
|
|
/**************************************************************************
|
|
* Private Function Prototypes
|
|
**************************************************************************/
|
|
|
|
/**************************************************************************
|
|
* Global Variables
|
|
**************************************************************************/
|
|
|
|
/**************************************************************************
|
|
* Private Variables
|
|
**************************************************************************/
|
|
|
|
/**************************************************************************
|
|
* Private Functions
|
|
**************************************************************************/
|
|
|
|
/**************************************************************************
|
|
* Public Functions
|
|
**************************************************************************/
|
|
|
|
int pthread_cancel(pthread_t thread)
|
|
{
|
|
_TCB *tcb;
|
|
|
|
/* First, make sure that the handle references a valid thread */
|
|
|
|
if (!thread)
|
|
{
|
|
/* pid == 0 is the IDLE task. Callers cannot cancel the
|
|
* IDLE task.
|
|
*/
|
|
|
|
return ESRCH;
|
|
}
|
|
|
|
tcb = sched_gettcb((pid_t)thread);
|
|
if (!tcb)
|
|
{
|
|
/* The pid does not correspond to any known thread */
|
|
|
|
return ESRCH;
|
|
}
|
|
|
|
/* Check to see if this thread has the non-cancelable bit set in its
|
|
* flags. Suppress context changes for a bit so that the flags are stable.
|
|
* (the flags should not change in interrupt handling.
|
|
*/
|
|
|
|
sched_lock();
|
|
if ((tcb->flags & TCB_FLAG_NONCANCELABLE) != 0)
|
|
{
|
|
/* Then we cannot cancel the thread now. Here is how this is
|
|
* supposed to work:
|
|
*
|
|
* "When cancelability is disabled, all cancels are held pending
|
|
* in the target thread until the thread changes the cancelability.
|
|
* When cancelability is deferred, all cancels are held pending in
|
|
* the target thread until the thread changes the cancelability, calls
|
|
* a function which is a cancellation point or calls pthread_testcancel(),
|
|
* thus creating a cancellation point. When cancelability is asynchronous,
|
|
* all cancels are acted upon immediately, interrupting the thread with its
|
|
* processing."
|
|
*/
|
|
|
|
tcb->flags |= TCB_FLAG_CANCEL_PENDING;
|
|
sched_unlock();
|
|
return OK;
|
|
}
|
|
|
|
sched_unlock();
|
|
|
|
/* Check to see if the ID refers to ourselves.. this would be the
|
|
* same as pthread_exit(PTHREAD_CANCELED).
|
|
*/
|
|
|
|
if (tcb == (_TCB*)g_readytorun.head)
|
|
{
|
|
pthread_exit(PTHREAD_CANCELED);
|
|
}
|
|
|
|
/* Complete pending join operations */
|
|
|
|
(void)pthread_completejoin((pid_t)thread, PTHREAD_CANCELED);
|
|
|
|
/* Then let pthread_delete do the real work */
|
|
|
|
task_delete((pid_t)thread);
|
|
return OK;
|
|
}
|
|
|
|
|