82 lines
2.9 KiB
ArmAsm
82 lines
2.9 KiB
ArmAsm
/*-
|
|
* Copyright (c) 1990 The Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* the Systems Programming Group of the University of Utah Computer
|
|
* Science Department.
|
|
*
|
|
* 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. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
|
|
*/
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
.text
|
|
/*.asciz "from: @(#)Ovfork.s 5.1 (Berkeley) 5/12/90"*/
|
|
.asciz "$Id: Ovfork.S,v 1.4 1994/01/27 15:00:49 mycroft Exp $"
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
#include "SYS.h"
|
|
|
|
/*
|
|
* @(#)vfork.s 4.1 (Berkeley) 12/21/80
|
|
* C library -- vfork
|
|
*/
|
|
|
|
/*
|
|
* pid = vfork();
|
|
*
|
|
* d1 == 0 in parent process, d1 == 1 in child process.
|
|
* d0 == pid of child in parent, d0 == pid of parent in child.
|
|
*
|
|
* trickery here, due to keith sklower, uses ret to clear the stack,
|
|
* and then returns with a jump indirect, since only one person can return
|
|
* with a ret off this stack... we do the ret before we vfork!
|
|
*/
|
|
|
|
ENTRY(vfork)
|
|
movl sp@+,a0
|
|
movl #SYS_vfork,d0
|
|
trap #0
|
|
jcs err
|
|
subql #1,d1 /* from 1 to 0 in child, 0 to -1 in parent */
|
|
andl d1,d0
|
|
jmp a0@
|
|
err:
|
|
.globl _errno
|
|
#ifdef PIC
|
|
movel #__GLOBAL_OFFSET_TABLE_,a1
|
|
lea pc@(0,a1:l),a1
|
|
movl a1@(_errno:w),a1
|
|
movl d0,a1@
|
|
#else
|
|
movl d0,_errno
|
|
#endif
|
|
moveq #-1,d0
|
|
jmp a0@
|