nuttx/libs/libc/signal/sig_pause.c
2020-10-28 07:12:46 +01:00

85 lines
3.0 KiB
C

/****************************************************************************
* libs/libc/signal/sig_pause.c
*
* Copyright (C) 2015 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 <unistd.h>
#include <signal.h>
#include <sched.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sigpause
*
* Description:
* The sigpause() will remove sig from the calling process' signal mask
* and suspend the calling process until a signal is received. The
* sigpause() function will restore the process' signal mask to its
* original state before returning.
*
****************************************************************************/
int sigpause(int signo)
{
sigset_t set;
int ret;
/* Get the current set of blocked signals */
sched_lock();
ret = sigprocmask(SIG_SETMASK, NULL, &set);
if (ret == OK)
{
/* Remove the 'signo' from the set of blocked signals */
ret = sigdelset(&set, signo);
}
/* Let sigsuspend do the rest of the job */
if (ret == OK)
{
ret = sigsuspend(&set);
}
sched_unlock();
return ret;
}