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/* Copyright (C) 1996-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Schwab (schwab@issan.informatik.uni-dortmund.de)
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/>. */
/* 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>
#ifdef RESET_PID
#include <tls.h>
#endif
#define CLONE_VM 0x00000100
#define CLONE_THREAD 0x00010000
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
void *parent_tidptr, void *tls, void *child_tidptr) */
.text
ENTRY (__clone)
/* Sanity check arguments. */
movel #-EINVAL, %d0
movel 4(%sp), %a0 /* no NULL function pointers */
tstl %a0
jeq SYSCALL_ERROR_LABEL
movel 8(%sp), %a1 /* no NULL stack pointers */
tstl %a1
jeq SYSCALL_ERROR_LABEL
/* Allocate space and copy the argument onto the new stack. */
movel 16(%sp), -(%a1)
/* Do the system call */
movel 12+0(%sp), %d1 /* get flags */
movel %d3, -(%a1) /* save %d3 and get parent_tidptr */
movel %d3, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d3, 0)
movel 20+4(%sp), %d3
movel %d4, -(%a1) /* save %d4 and get child_tidptr */
movel %d4, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d4, 0)
movel 28+8(%sp), %d4
movel %d5, -(%a1) /* save %d5 and get tls */
movel %d5, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d5, 0)
movel 24+12(%sp), %d5
/* save %d2 and get stack pointer */
#ifdef __mcoldfire__
movel %d2, -(%a1)
movel %d2, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d2, 0)
movel %a1, %d2
#else
exg %d2, %a1 /* save %d2 and get stack pointer */
cfi_register (%d2, %a1)
#endif
movel #SYS_ify (clone), %d0
/* End FDE now, because in the child the unwind info will be
wrong. */
cfi_endproc
trap #0
#ifdef __mcoldfire__
movel (%sp)+, %d2
#else
exg %d2, %a1 /* restore %d2 */
#endif
movel (%sp)+, %d5 /* restore %d5, %d4 and %d3 */
movel (%sp)+, %d4
movel (%sp)+, %d3
tstl %d0
jmi SYSCALL_ERROR_LABEL
jeq thread_start
rts
thread_start:
cfi_startproc
cfi_undefined (pc) /* Mark end of stack */
subl %fp, %fp /* terminate the stack frame */
#ifdef RESET_PID
/* Check and see if we need to reset the PID. */
movel %d1, %a1
andl #CLONE_THREAD, %d1
jne donepid
movel %a1, %d1
movel #-1, %d0
andl #CLONE_VM, %d1
jne gotpid
movel #SYS_ify (getpid), %d0
trap #0
gotpid:
movel %a0, -(%sp)
movel %d0, -(%sp)
bsrl __m68k_read_tp@PLTPC
movel (%sp)+, %d0
movel %d0, PID_OFFSET(%a0)
movel %d0, TID_OFFSET(%a0)
movel (%sp)+, %a0
donepid:
#endif
jsr (%a0)
movel %d0, %d1
movel #SYS_ify (exit), %d0
trap #0
cfi_endproc
cfi_startproc
PSEUDO_END (__clone)
weak_alias (__clone, clone)
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