incubator-nuttx/include/nuttx/cancelpt.h

153 lines
5.8 KiB
C

/****************************************************************************
* include/nuttx/cancelpt.h
* Definitions related to cancellation points
*
* Copyright (C) 2016 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.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_CANCELPT_H
#define __INCLUDE_NUTTX_CANCELPT_H
/****************************************************************************
* Cancellation Points.
*
* Cancellation points shall occur when a thread is executing the following
* functions:
*
* accept() mq_timedsend() putpmsg() sigtimedwait()
* aio_suspend() msgrcv() pwrite() sigwait()
* clock_nanosleep() msgsnd() read() sigwaitinfo()
* close() msync() readv() sleep()
* connect() nanosleep() recv() system()
* creat() open() recvfrom() tcdrain()
* fcntl() pause() recvmsg() usleep()
* fdatasync() poll() select() wait()
* fsync() pread() sem_timedwait() waitid()
* getmsg() pselect() sem_wait() waitpid()
* getpmsg() pthread_cond_timedwait() send() write()
* lockf() pthread_cond_wait() sendmsg() writev()
* mq_receive() pthread_join() sendto()
* mq_send() pthread_testcancel() sigpause()
* mq_timedreceive() putmsg() sigsuspend()
*
* Each of the above function must call enter_cancellation_point() on entry
* in order to establish the cancellation point and leave_cancellation_point()
* on exit. These functions are described below.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdbool.h>
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: enter_cancellation_point
*
* Description:
* Called at the beginning of the cancellation point to establish the
* cancellation point. This function does the following:
*
* 1. If deferred cancellation does not apply to this thread, nothing is
* done, otherwise, it
* 2. Sets state information in the caller's TCB and increments a nesting
* count.
* 3. If this is the outermost nesting level, it checks if there is a
* pending cancellation and, if so, calls either exit() or
* pthread_exit(), depending upon the type of the thread.
*
* Input Parameters:
* None
*
* Returned Value
* true is returned if a cancellation is pending but cannot be performed
* now due to the nesting level.
*
****************************************************************************/
#ifdef CONFIG_CANCELLATION_POINTS
bool enter_cancellation_point(void);
#else
# define enter_cancellation_point() false
#endif
/****************************************************************************
* Name: leave_cancellation_point
*
* Description:
* Called at the end of the cancellation point. This function does the
* following:
*
* 1. If deferred cancellation does not apply to this thread, nothing is
* done, otherwise, it
* 2. Clears state information in the caller's TCB and decrements a
* nesting count.
* 3. If this is the outermost nesting level, it checks if there is a
* pending cancellation and, if so, calls either exit() or
* pthread_exit(), depending upon the type of the thread.
*
* Input Parameters:
* None
*
* Returned Value
* None
*
****************************************************************************/
#ifdef CONFIG_CANCELLATION_POINTS
void leave_cancellation_point(void);
#else
# define leave_cancellation_point()
#endif
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __INCLUDE_NUTTX_CANCELPT_H */