1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
/* Copyright (C) 1996, 1997 Free Software Foundation, Inc.
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 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 <sysdep.h>
#define _ERRNO_H 1
#include <errnos.h>
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */
.text
ENTRY (__clone)
/* Sanity check arguments. */
movel #-EINVAL, %d0
movel 4(%sp), %a0 /* no NULL function pointers */
tstl %a0
jeq syscall_error
movel 8(%sp), %a1 /* no NULL stack pointers */
tstl %a1
jeq syscall_error
/* Allocate space and copy the argument onto the new stack. */
movel 16(%sp), -(%a1)
/* Do the system call */
exg %d2, %a1 /* save %d2 and get stack pointer */
movel 12(%sp), %d1 /* get flags */
movel #SYS_ify (clone), %d0
trap #0
exg %d2, %a1 /* restore %d2 */
tstl %d0
jmi syscall_error
jeq thread_start
rts
thread_start:
subl %fp, %fp /* terminate the stack frame */
jsr (%a0)
movel %d0, -(%sp)
jbsr JUMPTARGET (_exit)
PSEUDO_END (__clone)
weak_alias (__clone, clone)
|