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
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
|
/* Copyright (C) 2003-2024 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 <errno.h>
#include <error.h>
#include <limits.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <ucontext.h>
#include <support/support.h>
#define N 4
#if __WORDSIZE == 64
#define GUARD_PATTERN 0xdeadbeafdeadbeaf
#else
#define GUARD_PATTERN 0xdeadbeaf
#endif
typedef struct {
ucontext_t uctx;
unsigned long guard[3];
} tst_context_t;
static char *stacks[N];
static size_t stack_size;
static tst_context_t ctx[N][2];
static volatile int failures;
static void
fct (long int n)
{
char on_stack[1];
/* Just to use the thread local descriptor. */
printf ("%ld: in %s now, on_stack = %p\n", n, __FUNCTION__, on_stack);
errno = 0;
if (ctx[n][1].uctx.uc_link != &ctx[n][0].uctx)
{
printf ("context[%ld][1] uc_link damaged, = %p\n", n,
ctx[n][1].uctx.uc_link);
exit (1);
}
if ((ctx[n][0].guard[0] != GUARD_PATTERN)
|| (ctx[n][0].guard[1] != GUARD_PATTERN)
|| (ctx[n][0].guard[2] != GUARD_PATTERN))
{
printf ("%ld: %s context[0] overflow detected!\n", n, __FUNCTION__);
++failures;
}
if ((ctx[n][1].guard[0] != GUARD_PATTERN)
|| (ctx[n][1].guard[1] != GUARD_PATTERN)
|| (ctx[n][1].guard[2] != GUARD_PATTERN))
{
printf ("%ld: %s context[1] overflow detected!\n", n, __FUNCTION__);
++failures;
}
if (n < 0 || n >= N)
{
printf ("%ld out of range\n", n);
exit (1);
}
if (on_stack < stacks[n] || on_stack >= stacks[n] + stack_size)
{
printf ("%ld: on_stack not on appropriate stack\n", n);
exit (1);
}
}
static void *
tf (void *arg)
{
int n = (int) (long int) arg;
ctx[n][0].guard[0] = GUARD_PATTERN;
ctx[n][0].guard[1] = GUARD_PATTERN;
ctx[n][0].guard[2] = GUARD_PATTERN;
ctx[n][1].guard[0] = GUARD_PATTERN;
ctx[n][1].guard[1] = GUARD_PATTERN;
ctx[n][1].guard[2] = GUARD_PATTERN;
if (getcontext (&ctx[n][1].uctx) != 0)
{
printf ("%d: cannot get context: %m\n", n);
exit (1);
}
printf ("%d: %s: before makecontext\n", n, __FUNCTION__);
ctx[n][1].uctx.uc_stack.ss_sp = stacks[n];
ctx[n][1].uctx.uc_stack.ss_size = stack_size;
ctx[n][1].uctx.uc_link = &ctx[n][0].uctx;
makecontext (&ctx[n][1].uctx, (void (*) (void)) fct, 1, (long int) n);
printf ("%d: %s: before swapcontext\n", n, __FUNCTION__);
if (swapcontext (&ctx[n][0].uctx, &ctx[n][1].uctx) != 0)
{
++failures;
printf ("%d: %s: swapcontext failed\n", n, __FUNCTION__);
}
else
printf ("%d: back in %s\n", n, __FUNCTION__);
return NULL;
}
static volatile int global;
static int
do_test (void)
{
int n;
pthread_t th[N];
ucontext_t mctx;
stack_size = 2 * PTHREAD_STACK_MIN;
for (int i = 0; i < N; i++)
stacks[i] = xmalloc (stack_size);
puts ("making contexts");
if (getcontext (&mctx) != 0)
{
if (errno == ENOSYS)
{
puts ("context handling not supported");
exit (0);
}
printf ("%s: getcontext: %m\n", __FUNCTION__);
exit (1);
}
/* Play some tricks with this context. */
if (++global == 1)
if (setcontext (&mctx) != 0)
{
puts ("setcontext failed");
exit (1);
}
if (global != 2)
{
puts ("global not incremented twice");
exit (1);
}
puts ("global OK");
pthread_attr_t at;
if (pthread_attr_init (&at) != 0)
{
puts ("attr_init failed");
return 1;
}
if (pthread_attr_setstacksize (&at, 1 * 1024 * 1024) != 0)
{
puts ("attr_setstacksize failed");
return 1;
}
for (n = 0; n < N; ++n)
if (pthread_create (&th[n], &at, tf, (void *) (long int) n) != 0)
{
puts ("create failed");
exit (1);
}
if (pthread_attr_destroy (&at) != 0)
{
puts ("attr_destroy failed");
return 1;
}
for (n = 0; n < N; ++n)
if (pthread_join (th[n], NULL) != 0)
{
puts ("join failed");
exit (1);
}
for (int i = 0; i < N; i++)
free (stacks[i]);
return failures;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
|
