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
65
66
67
68
69
70
71
72
73
74
75
|
/*
* Copyright (C) Igor Sysoev
*/
#include <sys/syscall.h>
#include <machine/asm.h>
/*
* rfork_thread(3) - rfork_thread(flags, stack, func, arg);
*/
#define KERNCALL int $0x80
ENTRY(rfork_thread)
push %ebp
mov %esp, %ebp
push %esi
mov 12(%ebp), %esi # the stack address
sub $4, %esi
mov 20(%ebp), %eax # the thread argument
mov %eax, (%esi)
sub $4, %esi
mov 16(%ebp), %eax # the start thread address
mov %eax, (%esi)
push 8(%ebp) # rfork(2) flags
push $0
mov $SYS_rfork, %eax
KERNCALL
jc error
cmp $0, %edx
jne child
parent:
add $8, %esp
pop %esi
mov %ebp, %esp
pop %ebp
ret
child:
mov %esi, %esp
pop %eax
call *%eax # call a thread start address ...
add $4, %esp
push %eax
push $0
mov $SYS_exit, %eax # ... and exit(2) after a thread would return
KERNCALL
error:
add $8, %esp
pop %esi
mov %ebp, %esp
pop %ebp
PIC_PROLOGUE
/* libc's cerror: jmp PIC_PLT(HIDENAME(cerror)) */
push %eax
call PIC_PLT(CNAME(__error))
pop %ecx
PIC_EPILOGUE
mov %ecx, (%eax)
mov $-1, %eax
mov $-1, %edx
ret
|