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/* $OpenBSD: uthread_wait4.c,v 1.7 2001/11/09 00:20:26 marc Exp $ */
/*
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
* All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 AUTHOR 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.
*
* $FreeBSD: uthread_wait4.c,v 1.5 1999/08/28 00:03:53 peter Exp $
*/
#include <errno.h>
#include <sys/wait.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
/*
* Note: a thread calling wait4 may have its state changed to waiting
* until awakened by a signal. Also note that system(3), for example,
* blocks SIGCHLD and calls waitpid (which calls wait4). If the process
* started by system(3) doesn't finish before this function is called the
* function will never awaken -- system(3) also ignores SIGINT and SIGQUIT.
*
* Thus always unmask SIGCHLD here.
*/
pid_t
wait4(pid_t pid, int *istat, int options, struct rusage * rusage)
{
struct pthread *curthread = _get_curthread();
pid_t ret;
sigset_t mask, omask;
/* This is a cancellation point: */
_thread_enter_cancellation_point();
_thread_kern_sig_defer();
sigemptyset(&mask);
sigaddset(&mask, SIGCHLD);
sigprocmask(SIG_UNBLOCK, &mask, &omask);
/* Perform a non-blocking wait4 syscall: */
while ((ret = _thread_sys_wait4(pid, istat, options | WNOHANG, rusage)) == 0 && (options & WNOHANG) == 0) {
/* Reset the interrupted operation flag: */
curthread->interrupted = 0;
/* Schedule the next thread while this one waits: */
_thread_kern_sched_state(PS_WAIT_WAIT, __FILE__, __LINE__);
/* Check if this call was interrupted by a signal: */
if (curthread->interrupted) {
errno = EINTR;
ret = -1;
break;
}
}
sigprocmask(SIG_SETMASK, &omask, NULL);
_thread_kern_sig_undefer();
/* No longer in a cancellation point: */
_thread_leave_cancellation_point();
return (ret);
}
#endif
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