1 files changed, 74 insertions, 0 deletions
diff --git a/lib/libc/sys/w_fork.c b/lib/libc/sys/w_fork.c
new file mode 100644
index 00000000000..1c6080e0cbd
--- /dev/null
+++ b/lib/libc/sys/w_fork.c
@@ -0,0 +1,74 @@
+/*	$OpenBSD: w_fork.c,v 1.1 2015/04/07 01:27:07 guenther Exp $ */
+
+/*
+ * Copyright (c) 2008 Kurt Miller <kurt@openbsd.org>
+ * Copyright (c) 2008 Philip Guenther <guenther@openbsd.org>
+ * Copyright (c) 2003 Daniel Eischen <deischen@freebsd.org>
+ * 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. 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 THE AUTHOR 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: /repoman/r/ncvs/src/lib/libc_r/uthread/uthread_atfork.c,v 1.1 2004/12/10 03:36:45 grog Exp $
+ */
+
+#include <unistd.h>
+#include "thread_private.h"
+#include "atfork.h"
+
+/* define and initialize the list */
+struct atfork_listhead _atfork_list = TAILQ_HEAD_INITIALIZER(_atfork_list);
+
+pid_t	_thread_fork(void);
+
+pid_t
+fork(void)
+{
+	struct atfork_fn *p;
+	pid_t newid;
+
+	/*
+	 * In the common case the list is empty; remain async-signal-safe
+	 * then by skipping the locking and just forking
+	 */
+	if (TAILQ_FIRST(&_atfork_list) == NULL)
+		return (_thread_fork());
+
+	_ATFORK_LOCK();
+	TAILQ_FOREACH_REVERSE(p, &_atfork_list, atfork_listhead, fn_next)
+		if (p->fn_prepare)
+			p->fn_prepare();
+
+	newid = _thread_fork();
+
+	if (newid == 0) {
+		TAILQ_FOREACH(p, &_atfork_list, fn_next)
+			if (p->fn_child)
+				p->fn_child();
+	} else {
+		TAILQ_FOREACH(p, &_atfork_list, fn_next)
+			if (p->fn_parent)
+				p->fn_parent();
+	}
+	_ATFORK_UNLOCK();
+
+	return (newid);
+}