73 lines
2.8 KiB
ArmAsm
73 lines
2.8 KiB
ArmAsm
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/*
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* Copyright (c) 1983, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#if defined(SYSLIBC_SCCS) && !defined(lint)
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/* .asciz "@(#)Ovfork.s 8.1 (Berkeley) 6/4/93" */
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.asciz "$NetBSD: __vfork14.S,v 1.1 1998/01/04 20:58:14 thorpej Exp $"
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#endif /* SYSLIBC_SCCS and not lint */
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/*
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* @(#)vfork.s 4.1 (Berkeley) 12/21/80
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* C library -- vfork
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*/
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#include "SYS.h"
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/*
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* pid = vfork();
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*
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* r1 == 0 in parent process, r1 == 1 in child process.
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* r0 == pid of child in parent, r0 == pid of parent in child.
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*
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* trickery here, due to keith sklower, uses ret to clear the stack,
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* and then returns with a jump indirect, since only one person can return
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* with a ret off this stack... we do the ret before we vfork!
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*/
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ENTRY(__vfork14, 0)
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movl 16(fp),r2 # save return address before we smash it
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movab here,16(fp)
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ret
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here:
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chmk $ SYS___vfork14
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bcs err # if failed, set errno and return -1
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/* this next trick is Chris Torek's fault */
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mnegl r1,r1 # r1 = 0xffffffff if child, 0 if parent
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bicl2 r1,r0 # r0 &= ~r1, i.e., 0 if child, else unchanged
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jmp (r2)
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err:
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movl r0,_errno
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mnegl $1,r0
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jmp (r2)
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