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/*
* 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.
*
* $FreeBSD$
*/
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <pthread.h>
#include <spinlock.h>
#include <sys/signalvar.h>
#include "libc_private.h"
#include "thr_private.h"
/*
* For a while, allow libpthread to work with a libc that doesn't
* export the malloc lock.
*/
#pragma weak __malloc_lock
__weak_reference(_fork, fork);
pid_t
_fork(void)
{
sigset_t sigset, oldset;
struct pthread *curthread;
struct pthread_atfork *af;
pid_t ret;
int errsave;
if (!_kse_isthreaded())
return (__sys_fork());
curthread = _get_curthread();
/*
* Masks all signals until we reach a safe point in
* _kse_single_thread, and the signal masks will be
* restored in that function, for M:N thread, all
* signals were already masked in kernel atomically,
* we only need to do this for bound thread.
*/
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
SIGFILLSET(sigset);
__sys_sigprocmask(SIG_SETMASK, &sigset, &oldset);
}
_pthread_mutex_lock(&_thr_atfork_mutex);
/* Run down atfork prepare handlers. */
TAILQ_FOREACH_REVERSE(af, &_thr_atfork_list, atfork_head, qe) {
if (af->prepare != NULL)
af->prepare();
}
/* Fork a new process: */
if ((_kse_isthreaded() != 0) && (__malloc_lock != NULL)) {
_spinlock(__malloc_lock);
}
if ((ret = __sys_fork()) == 0) {
/* Child process */
errsave = errno;
/* Kernel signal mask is restored in _kse_single_thread */
_kse_single_thread(curthread);
/* Run down atfork child handlers. */
TAILQ_FOREACH(af, &_thr_atfork_list, qe) {
if (af->child != NULL)
af->child();
}
_thr_mutex_reinit(&_thr_atfork_mutex);
} else {
if ((_kse_isthreaded() != 0) && (__malloc_lock != NULL)) {
_spinunlock(__malloc_lock);
}
errsave = errno;
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
__sys_sigprocmask(SIG_SETMASK, &oldset, NULL);
}
/* Run down atfork parent handlers. */
TAILQ_FOREACH(af, &_thr_atfork_list, qe) {
if (af->parent != NULL)
af->parent();
}
_pthread_mutex_unlock(&_thr_atfork_mutex);
}
errno = errsave;
/* Return the process ID: */
return (ret);
}
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