1 /* $NetBSD: __clone.S,v 1.5 2013/07/16 23:00:15 matt Exp $ */
4 * Copyright (c) 2001 The NetBSD Foundation, Inc.
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Steve C. Woodford.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
32 #include <sys/errno.h>
36 WEAK_ALIAS(clone, __clone)
40 * int clone(int (*fn)(void *), void *stack, int flags, void *arg);
43 movl 4(%sp),%d0 /* NULL function pointer? */
44 jeq 2f /* Yup, bomb out */
46 movl 8(%sp),%d0 /* NULL stack? */
47 jeq 2f /* Yup, bomb out */
49 movl 16(%sp),-(%a0) /* Push clone's `arg' on its new stack */
50 lea -12(%a0),%a0 /* Fake syscall args for the clone */
51 movl %a0,-(%sp) /* Syscall arg: stack */
52 movl 16(%sp),-(%sp) /* Syscall arg: flags */
53 clrl -(%sp) /* Fake return address */
54 SYSTRAP(__clone) /* Note: `fn' in (a1) is preserved */
55 lea 12(%sp),%sp /* Zap syscall args */
56 jcs 3f /* Punt if syscall failed */
58 jne 1f /* We're the parent, just return. */
59 jsr (%a1) /* We're the clone, call the function */
60 movl %d0,-(%sp) /* If clone returns, invoke _exit(3) */
61 jbsr PIC_PLT(_C_LABEL(_exit))