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
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* tools/testing/selftests/kvm/lib/assert.c
*
* Copyright (C) 2018, Google LLC.
*/
#define _GNU_SOURCE /* for getline(3) and strchrnul(3)*/
#include "test_util.h"
#include <execinfo.h>
#include <sys/syscall.h>
#include "kselftest.h"
/* Dumps the current stack trace to stderr. */
static void __attribute__((noinline)) test_dump_stack(void);
static void test_dump_stack(void)
{
/*
* Build and run this command:
*
* addr2line -s -e /proc/$PPID/exe -fpai {backtrace addresses} | \
* grep -v test_dump_stack | cat -n 1>&2
*
* Note that the spacing is different and there's no newline.
*/
size_t i;
size_t n = 20;
void *stack[n];
const char *addr2line = "addr2line -s -e /proc/$PPID/exe -fpai";
const char *pipeline = "|cat -n 1>&2";
char cmd[strlen(addr2line) + strlen(pipeline) +
/* N bytes per addr * 2 digits per byte + 1 space per addr: */
n * (((sizeof(void *)) * 2) + 1) +
/* Null terminator: */
1];
char *c;
n = backtrace(stack, n);
c = &cmd[0];
c += sprintf(c, "%s", addr2line);
/*
* Skip the first 3 frames: backtrace, test_dump_stack, and
* test_assert. We hope that backtrace isn't inlined and the other two
* we've declared noinline.
*/
for (i = 2; i < n; i++)
c += sprintf(c, " %lx", ((unsigned long) stack[i]) - 1);
c += sprintf(c, "%s", pipeline);
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-result"
system(cmd);
#pragma GCC diagnostic pop
}
static pid_t _gettid(void)
{
return syscall(SYS_gettid);
}
void __attribute__((noinline))
test_assert(bool exp, const char *exp_str,
const char *file, unsigned int line, const char *fmt, ...)
{
va_list ap;
if (!(exp)) {
va_start(ap, fmt);
fprintf(stderr, "==== Test Assertion Failure ====\n"
" %s:%u: %s\n"
" pid=%d tid=%d - %s\n",
file, line, exp_str, getpid(), _gettid(),
strerror(errno));
test_dump_stack();
if (fmt) {
fputs(" ", stderr);
vfprintf(stderr, fmt, ap);
fputs("\n", stderr);
}
va_end(ap);
if (errno == EACCES) {
print_skip("Access denied - Exiting");
exit(KSFT_SKIP);
}
exit(254);
}
return;
}
|
