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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 *arg), void *child_stack, int flags, void *arg) */
.text
NESTED(__clone,4*SZREG,sp)
#ifdef __PIC__
.set noreorder
.cpload $25
.set reorder
subu sp,32
.cprestore 16
#else
subu sp,32
#endif
#ifdef PROF
.set noat
move $1,ra
jal _mcount
.set at
#endif
/* Sanity check arguments. */
li v0,EINVAL
beqz a0,error /* No NULL function pointers. */
beqz a1,error /* No NULL stack pointers. */
subu a1,32 /* Reserve argument save space. */
sw a0,0(a1) /* Save function pointer. */
sw a3,4(a1) /* Save argument 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 */
addiu sp,32
ret
/* Something bad happened -- no child created */
error:
addiu sp,32
#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. */
ENTRY(__thread_start)
/* cp is already loaded. */
.cprestore 16
/* The stackframe has been created on entry of clone(). */
/* Restore the arg for user's function. */
lw t9,0(sp) /* Function pointer. */
lw a0,4(sp) /* Argument pointer. */
/* 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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