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/* Copyright (C) 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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/>. */
/* vfork() is just a special case of clone(). */
#include <sys/syscall.h>
#include <sys/asm.h>
#include <sysdep.h>
#ifndef SAVE_PID
#define SAVE_PID
#endif
#ifndef RESTORE_PID
#define RESTORE_PID
#endif
#ifdef __NR_fork
/* int vfork() */
.text
.hidden __vfork
LOCALSZ= 1
FRAMESZ= (((NARGSAVE+LOCALSZ)*SZREG)+ALSZ)&ALMASK
GPOFF= FRAMESZ-(1*SZREG)
NESTED(__vfork,FRAMESZ,sp)
#ifdef __PIC__
SETUP_GP
#endif
PTR_SUBU sp, FRAMESZ
SETUP_GP64 (a5, __vfork)
#ifdef __PIC__
SAVE_GP (GPOFF)
#endif
PTR_ADDU sp, FRAMESZ
SAVE_PID
li a0, 0x4112 /* CLONE_VM | CLONE_VFORK | SIGCHLD */
move a1, sp
/* Do the system call */
li v0,__NR_clone
syscall
RESTORE_PID
bnez a3,L(error)
/* Successful return from the parent or child. */
RESTORE_GP64
j ra
nop
/* Something bad happened -- no child created. */
L(error):
move a0, v0
#ifdef __PIC__
PTR_LA t9, __syscall_error
RESTORE_GP64
jr t9
#else
RESTORE_GP64
j __syscall_error
#endif
END(__vfork)
weak_alias(__vfork,vfork)
libc_hidden_def(vfork)
#endif
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