thr_wait4.c revision 103388 
1/*
2 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by John Birrell.
16 * 4. Neither the name of the author nor the names of any co-contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * $FreeBSD: head/lib/libkse/thread/thr_wait4.c 103388 2002-09-16 08:45:36Z mini $
33 */
34#include <sys/types.h>
35
36#include <errno.h>
37#include <sys/wait.h>
38#include <pthread.h>
39#include "thr_private.h"
40
41__weak_reference(__wait4, wait4);
42
43pid_t
44_wait4(pid_t pid, int *istat, int options, struct rusage * rusage)
45{
46	struct pthread	*curthread = _get_curthread();
47	pid_t	ret;
48
49	_thread_kern_sig_defer();
50
51	/* Perform a non-blocking wait4 syscall: */
52	while ((ret = __sys_wait4(pid, istat, options | WNOHANG, rusage)) == 0 && (options & WNOHANG) == 0) {
53		/* Reset the interrupted operation flag: */
54		curthread->interrupted = 0;
55
56		/* Schedule the next thread while this one waits: */
57		_thread_kern_sched_state(PS_WAIT_WAIT, __FILE__, __LINE__);
58
59		/* Check if this call was interrupted by a signal: */
60		if (curthread->interrupted) {
61			errno = EINTR;
62			ret = -1;
63			break;
64		}
65	}
66
67	_thread_kern_sig_undefer();
68
69	return (ret);
70}
71
72pid_t
73__wait4(pid_t pid, int *istat, int options, struct rusage *rusage)
74{
75	pid_t ret;
76
77	_thread_enter_cancellation_point();
78	ret = _wait4(pid, istat, options, rusage);
79	_thread_leave_cancellation_point();
80
81	return ret;
82}
83