__vfork14.S revision 1.9
1 /* $NetBSD: __vfork14.S,v 1.9 2003/08/07 16:42:14 agc 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 1.9 2003/08/07 16:42:14 agc 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 62 ENTRY(__vfork14) 63 movl %sp@+,%a1 64 movl #SYS___vfork14,%d0 65 trap #0 66 jcs err 67 subql #1,%d1 /* from 1 to 0 in child, 0 to -1 in parent */ 68 andl %d1,%d0 69 jmp %a1@ 70 err: 71 #ifdef _REENTRANT 72 .globl _C_LABEL(__errno) 73 movl %a1,%sp@- 74 movl %d0,%sp@- 75 #if defined(PIC) && !defined(__ELF__) 76 movl #_C_LABEL(_GLOBAL_OFFSET_TABLE_),%a1 77 lea %pc@(0,a1:l),%a1 78 movl %a1@(_C_LABEL(__errno):l),%a1 79 jsr %a1@ 80 #else 81 jbsr PIC_PLT(_C_LABEL(__errno)) 82 #endif /* PIC */ 83 #ifdef __SVR4_ABI__ 84 movl %sp@+,%a0@ 85 #else 86 movl %d0,%a1 87 movl %sp@+,%a1@ 88 #endif 89 movl %sp@+,%a1 90 #else 91 .globl _C_LABEL(errno) 92 #ifdef PIC 93 #ifdef __ELF__ 94 lea %pc@(_GLOBAL_OFFSET_TABLE_@GOTPC),%a0 95 movl %a0@(_C_LABEL(errno)@GOT:w),%a0 96 #else 97 movl #_C_LABEL(_GLOBAL_OFFSET_TABLE_),%a0 98 lea %pc@(0,a0:l),%a0 99 movl %a0@(_C_LABEL(errno):w),%a0 100 #endif 101 movl %d0,%a0@ 102 #else 103 movl %d0,_C_LABEL(errno) 104 #endif /* PIC */ 105 #endif /* _REENTRANT */ 106 moveq #-1,%d0 107 jmp %a1@ 108
Indexes created Thu Sep 25 16:09:42 GMT 2025