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/* Copyright (C) 2005-2016 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/asm.h>
#include <sysdep.h>
#include <asm/unistd.h>
#include <sgidefs.h>
#include <tls.h>
/* int vfork() */
.text
.set nomips16
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
cfi_adjust_cfa_offset (FRAMESZ)
SETUP_GP64_REG (a5, __vfork)
#ifdef __PIC__
SAVE_GP (GPOFF)
#endif
#ifdef PROF
# if (_MIPS_SIM != _ABIO32)
PTR_S a5, GPOFF(sp)
# endif
.set noat
move $1, ra
# if (_MIPS_SIM == _ABIO32)
subu sp,sp,8
# endif
jal _mcount
.set at
# if (_MIPS_SIM != _ABIO32)
PTR_L a5, GPOFF(sp)
# endif
#endif
PTR_ADDU sp, FRAMESZ
cfi_adjust_cfa_offset (-FRAMESZ)
/* Save the PID value. */
READ_THREAD_POINTER(v1) /* Get the thread pointer. */
lw a2, PID_OFFSET(v1) /* Load the saved PID. */
subu a2, $0, a2 /* Negate it. */
bnez a2, 1f /* If it was zero... */
lui a2, 0x8000 /* use 0x80000000 instead. */
1: sw a2, PID_OFFSET(v1) /* Store the temporary PID. */
li a0, 0x4112 /* CLONE_VM | CLONE_VFORK | SIGCHLD */
move a1, sp
/* Do the system call */
li v0,__NR_clone
syscall
/* Restore the old PID value in the parent. */
beqz v0, 1f /* If we are the parent... */
READ_THREAD_POINTER(v1) /* Get the thread pointer. */
lw a2, PID_OFFSET(v1) /* Load the saved PID. */
subu a2, $0, a2 /* Re-negate it. */
lui a0, 0x8000 /* Load 0x80000000... */
bne a2, a0, 2f /* ... compare against it... */
li a2, 0 /* ... use 0 instead. */
2: sw a2, PID_OFFSET(v1) /* Restore the PID. */
1:
cfi_remember_state
bnez a3,L(error)
/* Successful return from the parent or child. */
RESTORE_GP64_REG
ret
/* Something bad happened -- no child created. */
L(error):
cfi_restore_state
#ifdef __PIC__
PTR_LA t9, __syscall_error
RESTORE_GP64_REG
jr t9
#else
RESTORE_GP64_REG
j __syscall_error
#endif
END(__vfork)
libc_hidden_def(__vfork)
weak_alias (__vfork, vfork)
strong_alias (__vfork, __libc_vfork)
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