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/* Copyright (C) 1996, 1997, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ralf Baechle <ralf@gnu.ai.mit.edu>, 1996.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* clone() is even more special than fork() as it mucks with stacks
and invokes a function in the right context after its all over. */
#include <sys/asm.h>
#include <asm/unistd.h>
#include <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
/* int clone(int (*fn)(), void *child_stack, int flags, void *arg) */
#define FRAMESZ 8*SZREG
#if _MIPS_SIM == _MIPS_SIM_ABI32
#define MAX_REG_ARGS 4
#else
#define MAX_REG_ARGS 6
#endif
.text
NESTED(__clone,FRAMESZ,sp)
#ifdef __PIC__
.set noreorder
.cpload $25
.set reorder
PTR_SUBIU sp,FRAMESZ
.cprestore SZREG*4
#else
PTR_SUBIU sp,FRAMESZ
#endif
#ifdef PROF
.set noat
move $1,ra
jal _mcount
.set at
#endif
REG_S s0,FRAMESZ-SZREG*2(sp)
REG_S s1,FRAMESZ-SZREG*3(sp)
/* Sanity check arguments. */
li v0,EINVAL
beqz a0,error /* no NULL function pointers */
beqz a1,error /* no NULL stack pointers */
/* Allocate space on the new stack and copy args over */
/* Save the arg for user's function */
move s0,a3 /* Save arg __thread_start. */
move s1,a0 /* Save func. pointer. */
/* Do the system call */
move a0,a2
li v0,__NR_clone
syscall
bnez a3,error
beqz v0,__thread_start
/* Successful return from the parent */
REG_L s0,FRAMESZ-SZREG*2(sp)
REG_L s1,FRAMESZ-SZREG*3(sp)
PTR_ADDIU sp,FRAMESZ
ret
/* Something bad happened -- no child created */
error:
REG_L s0,FRAMESZ-SZREG*2(sp)
REG_L s1,FRAMESZ-SZREG*3(sp)
PTR_ADDIU sp,FRAMESZ
#ifdef PIC
la t9,__syscall_error
jr t9
#else
j __syscall_error
#endif
END(__clone)
/* Load up the arguments to the function. Put this block of code in
its own function so that we can terminate the stack trace with our
debug info.
At this point we have s0=arg, s1=fn. */
NESTED(__thread_start,FRAMESZ,sp)
/* The stackframe has been created on entry of clone(). */
/* Resort the arg for user's function. */
move a0,s0
move t9,s1
/* Call the user's function. */
jalr t9
/* Call _exit rather than doing it inline for breakpoint purposes. */
move a0,v0
#ifdef __PIC__
la t9,_exit
jalr t9
#else
jal _exit
#endif
END(__thread_start)
weak_alias(__clone, clone)
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