xref: /freebsd/lib/libsys/arm/vfork.S (revision 80ffc7398b8302b2d54d783d8349e54d877a4250)
18269e767SBrooks Davis/*	$NetBSD: Ovfork.S,v 1.6 2003/08/07 16:42:03 agc Exp $	*/
28269e767SBrooks Davis
38269e767SBrooks Davis/*-
48269e767SBrooks Davis * Copyright (c) 1990 The Regents of the University of California.
58269e767SBrooks Davis * All rights reserved.
68269e767SBrooks Davis *
78269e767SBrooks Davis * Redistribution and use in source and binary forms, with or without
88269e767SBrooks Davis * modification, are permitted provided that the following conditions
98269e767SBrooks Davis * are met:
108269e767SBrooks Davis * 1. Redistributions of source code must retain the above copyright
118269e767SBrooks Davis *    notice, this list of conditions and the following disclaimer.
128269e767SBrooks Davis * 2. Redistributions in binary form must reproduce the above copyright
138269e767SBrooks Davis *    notice, this list of conditions and the following disclaimer in the
148269e767SBrooks Davis *    documentation and/or other materials provided with the distribution.
158269e767SBrooks Davis * 3. Neither the name of the University nor the names of its contributors
168269e767SBrooks Davis *    may be used to endorse or promote products derived from this software
178269e767SBrooks Davis *    without specific prior written permission.
188269e767SBrooks Davis *
198269e767SBrooks Davis * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
208269e767SBrooks Davis * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
218269e767SBrooks Davis * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
228269e767SBrooks Davis * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
238269e767SBrooks Davis * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
248269e767SBrooks Davis * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
258269e767SBrooks Davis * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
268269e767SBrooks Davis * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
278269e767SBrooks Davis * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
288269e767SBrooks Davis * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
298269e767SBrooks Davis * SUCH DAMAGE.
308269e767SBrooks Davis */
318269e767SBrooks Davis
328269e767SBrooks Davis#include <machine/asm.h>
338269e767SBrooks Davis#include "SYS.h"
348269e767SBrooks Davis
358269e767SBrooks Davis/*
368269e767SBrooks Davis * pid = vfork();
378269e767SBrooks Davis *
388269e767SBrooks Davis * On return from the SWI:
398269e767SBrooks Davis * r1 == 0 in parent process, r1 == 1 in child process.
408269e767SBrooks Davis * r0 == pid of child in parent, r0 == pid of parent in child.
418269e767SBrooks Davis */
428269e767SBrooks Davis	.text
438269e767SBrooks Davis	.align	0
448269e767SBrooks Davis
45*80ffc739SBrooks DavisENTRY(__sys_vfork)
46*80ffc739SBrooks Davis	.weak _C_LABEL(vfork);
47*80ffc739SBrooks Davis	.set _C_LABEL(vfork), _C_LABEL(__sys_vfork);
48*80ffc739SBrooks Davis	.weak _C_LABEL(_vfork);
49*80ffc739SBrooks Davis	.set _C_LABEL(_vfork), _C_LABEL(__sys_vfork);
508269e767SBrooks Davis	mov	r2, r14
518269e767SBrooks Davis	_SYSCALL(vfork)
528269e767SBrooks Davis	bcs	PIC_SYM(CERROR, PLT)
538269e767SBrooks Davis	sub	r1, r1, #1	/* r1 == 0xffffffff if parent, 0 if child */
548269e767SBrooks Davis	and	r0, r0, r1	/* r0 == 0 if child, else unchanged */
558269e767SBrooks Davis	mov	r15, r2
56*80ffc739SBrooks DavisEND(__sys_vfork)
578269e767SBrooks Davis
588269e767SBrooks Davis	.section .note.GNU-stack,"",%progbits
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