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/* Copyright (C) 1996, 1997, 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <rth@tamu.edu>, 1996.
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. */
/* 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 <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#define CLONE_VM 0x00000100
#define CLONE_THREAD 0x00010000
/* int clone(int (*fn)(void *arg), void *child_stack, int flags,
void *arg, pid_t *ptid, void *tls, pid_t *ctid);
Note that everything past ARG is technically optional, based
on FLAGS, and that CTID is arg 7, and thus is on the stack.
However, since a load from top-of-stack better be legal always,
we don't bother checking FLAGS. */
.text
ENTRY(__clone)
#ifdef PROF
ldgp gp,0(pv)
.set noat
lda AT, _mcount
jsr AT, (AT), _mcount
.set at
.prologue 1
#else
.prologue 0
#endif
/* Sanity check arguments. */
ldiq v0,EINVAL
beq a0,$error /* no NULL function pointers */
beq a1,$error /* no NULL stack pointers */
/* Save the fn ptr and arg on the new stack. */
subq a1,32,a1
stq a0,0(a1)
stq a3,8(a1)
#ifdef RESET_PID
stq a2,16(a1)
#endif
/* The syscall is of the form clone(flags, usp, ptid, ctid, tls).
Shift the flags, ptid, ctid, tls arguments into place; the
child_stack argument is already correct. */
mov a2,a0
mov a4,a2
ldq a3,0(sp)
mov a5,a4
/* Do the system call. */
ldiq v0,__NR_clone
call_pal PAL_callsys
bne a3,$error
beq v0,thread_start
/* Successful return from the parent. */
ret
/* Something bad happened -- no child created. */
$error:
#ifndef PROF
br gp,1f
1: ldgp gp,0(gp)
#endif
SYSCALL_ERROR_HANDLER
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. */
.ent thread_start
thread_start:
.frame fp,0,fp,0
mov 0, fp
.prologue 0
#ifdef RESET_PID
/* Check and see if we need to reset the PID. */
ldq t0,16(sp)
lda t1,CLONE_THREAD
and t0,t1,t2
beq t2,2f
1:
#endif
/* Load up the arguments. */
ldq pv,0(sp)
ldq a0,8(sp)
addq sp,32,sp
/* Call the user's function. */
jsr ra,(pv)
ldgp gp,0(ra)
/* Call _exit rather than doing it inline for breakpoint purposes. */
mov v0,a0
#ifdef PIC
bsr ra, HIDDEN_JUMPTARGET(_exit) !samegp
#else
jsr ra, HIDDEN_JUMPTARGET(_exit)
#endif
/* Die horribly. */
halt
#ifdef RESET_PID
2:
rduniq
lda t1, CLONE_VM
mov v0, s0
lda v0, -1
and t0, t1, t2
bne t2, 3f
lda v0, __NR_getxpid
callsys
3:
stl v0, PID_OFFSET(s0)
stl v0, TID_OFFSET(s0)
br 1b
#endif
.end thread_start
weak_alias (__clone, clone)
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