1/* $NetBSD: __vfork14.S,v 1.12 2013/09/12 15:36:15 joerg Exp $ */ 2 3/*- 4 * Copyright (c) 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36#include "SYS.h" 37 38#if defined(LIBC_SCCS) && !defined(lint) 39#if 0 40 RCSID("from: @(#)Ovfork.s 5.1 (Berkeley) 5/12/90") 41#else 42 RCSID("$NetBSD: __vfork14.S,v 1.12 2013/09/12 15:36:15 joerg Exp $") 43#endif 44#endif /* LIBC_SCCS and not lint */ 45 46/* 47 * @(#)vfork.s 4.1 (Berkeley) 12/21/80 48 * C library -- vfork 49 */ 50 51/* 52 * pid = vfork(); 53 * 54 * d1 == 0 in parent process, d1 == 1 in child process. 55 * d0 == pid of child in parent, d0 == pid of parent in child. 56 * 57 * trickery here, due to keith sklower, uses ret to clear the stack, 58 * and then returns with a jump indirect, since only one person can return 59 * with a ret off this stack... we do the ret before we vfork! 60 */ 61 62ENTRY(__vfork14) 63 movl (%sp)+,%a1 64 SYSTRAP(__vfork14) 65 jcs err 66 subql #1,%d1 /* from 1 to 0 in child, 0 to -1 in parent */ 67 andl %d1,%d0 68 jmp (%a1) 69err: 70#ifdef _REENTRANT 71 .globl _C_LABEL(__errno) 72 movl %a1,-(%sp) 73 movl %d0,-(%sp) 74 jbsr PIC_PLT(_C_LABEL(__errno)) 75#ifdef __SVR4_ABI__ 76 movl (%sp)+,(%a0) 77#else 78 movl %d0,%a1 79 movl (%sp)+,(%a1) 80#endif 81 movl (%sp)+,%a1 82#else 83#ifdef __PIC__ 84 GOT_SETUP(%a0) 85 movl _C_LABEL(errno)@GOT:w(%a0),%a0 86 movl %d0,(%a0) 87#else 88 .globl _C_LABEL(errno) 89 movl %d0,_C_LABEL(errno) 90#endif /* __PIC__ */ 91#endif /* _REENTRANT */ 92 moveq #-1,%d0 93 jmp (%a1) 94END(__vfork14) 95