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/* Copyright (C) 1999, 2002, 2003, 2005 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#include <kernel-features.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)
#ifdef __NR_vfork
#ifdef SAVE_PID
SAVE_PID
#endif
#ifdef __ARM_EABI__
/* 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
str r7, [sp, #-4]!
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);
#else
swi SYS_ify(vfork)
#endif
#ifdef RESTORE_PID
RESTORE_PID
#endif
cmn a1, #4096
RETINSTR(cc, lr)
# ifdef __ASSUME_VFORK_SYSCALL
b PLTJMP(SYSCALL_ERROR)
# else
/* Check if vfork syscall is known at all. */
cmn a1, #ENOSYS
bne PLTJMP(SYSCALL_ERROR)
# endif
#endif
#ifndef __ASSUME_VFORK_SYSCALL
/* If we don't have vfork, fork is close enough. */
DO_CALL (fork, 0)
cmn a1, #4096
RETINSTR(cc, lr)
b PLTJMP(SYSCALL_ERROR)
#elif !defined __NR_vfork
# error "__NR_vfork not available and __ASSUME_VFORK_SYSCALL defined"
#endif
PSEUDO_END (__vfork)
libc_hidden_def (__vfork)
weak_alias (__vfork, vfork)
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