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
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
/* Check multiple makecontext calls.
Copyright (C) 2018-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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
<https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <stdlib.h>
#include <ucontext.h>
static ucontext_t uctx_main, uctx_func1, uctx_func2;
const char *str1 = "\e[31mswapcontext(&uctx_func1, &uctx_main)\e[0m";
const char *str2 = "\e[34mswapcontext(&uctx_func2, &uctx_main)\e[0m";
const char *fmt1 = "\e[31m";
const char *fmt2 = "\e[34m";
#define handle_error(msg) \
do { perror(msg); exit(EXIT_FAILURE); } while (0)
__attribute__((noinline, noclone))
static void
func4(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
{
printf(" %sfunc4: %s\e[0m\n", fmt, str);
if (swapcontext(uocp, ucp) == -1)
handle_error("swapcontext");
printf(" %sfunc4: returning\e[0m\n", fmt);
}
__attribute__((noinline, noclone))
static void
func3(ucontext_t *uocp, ucontext_t *ucp, const char *str, const char *fmt)
{
printf(" %sfunc3: func4(uocp, ucp, str)\e[0m\n", fmt);
func4(uocp, ucp, str, fmt);
printf(" %sfunc3: returning\e[0m\n", fmt);
}
__attribute__((noinline, noclone))
static void
func1(void)
{
while ( 1 )
{
printf(" \e[31mfunc1: func3(&uctx_func1, &uctx_main, str1)\e[0m\n");
func3( &uctx_func1, &uctx_main, str1, fmt1);
}
}
__attribute__((noinline, noclone))
static void
func2(void)
{
while ( 1 )
{
printf(" \e[34mfunc2: func3(&uctx_func2, &uctx_main, str2)\e[0m\n");
func3(&uctx_func2, &uctx_main, str2, fmt2);
}
}
static int
do_test (void)
{
char func1_stack[16384];
char func2_stack[16384];
int i;
if (getcontext(&uctx_func1) == -1)
handle_error("getcontext");
uctx_func1.uc_stack.ss_sp = func1_stack;
uctx_func1.uc_stack.ss_size = sizeof (func1_stack);
uctx_func1.uc_link = &uctx_main;
makecontext(&uctx_func1, func1, 0);
if (getcontext(&uctx_func2) == -1)
handle_error("getcontext");
uctx_func2.uc_stack.ss_sp = func2_stack;
uctx_func2.uc_stack.ss_size = sizeof (func2_stack);
uctx_func2.uc_link = &uctx_func1;
makecontext(&uctx_func2, func2, 0);
for ( i = 0; i < 4; i++ )
{
if (swapcontext(&uctx_main, &uctx_func1) == -1)
handle_error("swapcontext");
printf(" \e[35mmain: swapcontext(&uctx_main, &uctx_func2)\n\e[0m");
if (swapcontext(&uctx_main, &uctx_func2) == -1)
handle_error("swapcontext");
printf(" \e[35mmain: swapcontext(&uctx_main, &uctx_func1)\n\e[0m");
}
printf("main: exiting\n");
exit(EXIT_SUCCESS);
}
#include <support/test-driver.c>
|
