1/* $NetBSD: __clone.S,v 1.2 2001/07/20 17:08:18 scw Exp $ */ 2 3/*- 4 * Copyright (c) 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Steve C. Woodford. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 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. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39#include <sys/errno.h> 40#include "SYS.h" 41 42#ifdef WEAK_ALIAS 43WEAK_ALIAS(clone, __clone) 44#endif 45 46/* 47 * int clone(int (*fn)(void *), void *stack, int flags, void *arg); 48 */ 49ENTRY(__clone) 50 movl %sp@(4),%d0 /* NULL function pointer? */ 51 jeq 2f /* Yup, bomb out */ 52 movl %d0,%a1 53 movl %sp@(8),%d0 /* NULL stack? */ 54 jeq 2f /* Yup, bomb out */ 55 movl %d0,%a0 56 movl %sp@(16),%a0@- /* Push clone's `arg' on its new stack */ 57 lea %a0@(-12),%a0 /* Fake syscall args for the clone */ 58 movl %a0,%sp@- /* Syscall arg: stack */ 59 movl %sp@(16),%sp@- /* Syscall arg: flags */ 60 clrl %sp@- /* Fake return address */ 61 SYSTRAP(__clone) /* Note: `fn' in a1@ is preserved */ 62 lea %sp@(12),%sp /* Zap syscall args */ 63 jcs 3f /* Punt if syscall failed */ 64 tstl %d0 65 jne 1f /* We're the parent, just return. */ 66 jsr %a1@ /* We're the clone, call the function */ 67 movl %d0,%sp@- /* If clone returns, invoke _exit(3) */ 68 jbsr PIC_PLT(_C_LABEL(_exit)) 69 /* NOTREACHED */ 701: rts 712: movl #EINVAL,%d0 723: jra PIC_PLT(CERROR) 73