/* Copyright (C) 1999-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Philip Blundell <philb@gnu.org>.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library.  If not, see

   <http://www.gnu.org/licenses/>.  */

#include <sysdep.h>

#define _ERRNO_H	1

#include <bits/errno.h>

#include <tcb-offsets.h>

/* Clone the calling process, but without copying the whole address space.

   The calling process is suspended until the new process exits or is

   replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,

   and the process ID of the new process to the old process.  */

ENTRY (__vfork)

	/* The DO_CALL macro saves r7 on the stack, to enable generation

	   of ARM unwind info.  Since the stack is initially shared between

	   parent and child of vfork, that saved value could be corrupted.

	   To avoid this problem, we save r7 into ip as well, and restore

	   from there.  */

	mov	ip, r7

	cfi_register (r7, ip)

	.fnstart

	push	{ r7 }

	cfi_adjust_cfa_offset (4)

	.save { r7 }

	ldr	r7, =SYS_ify (vfork)

	swi	0x0

	.fnend

	add	sp, sp, #4

	cfi_adjust_cfa_offset (-4)

	mov	r7, ip

	cfi_restore (r7)

	cmn	a1, #4096

	it	cc

	RETINSTR(cc, lr)

	b	PLTJMP(SYSCALL_ERROR)

PSEUDO_END (__vfork)

libc_hidden_def (__vfork)

weak_alias (__vfork, vfork)

strong_alias (__vfork, __libc_vfork)