Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * tools/testing/selftests/kvm/lib/assert.c
3 *
4 * Copyright (C) 2018, Google LLC.
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2.
7 */
8
9#define _GNU_SOURCE /* for getline(3) and strchrnul(3)*/
10
11#include "test_util.h"
12
13#include <execinfo.h>
14#include <sys/syscall.h>
15
16/* Dumps the current stack trace to stderr. */
17static void __attribute__((noinline)) test_dump_stack(void);
18static void test_dump_stack(void)
19{
20 /*
21 * Build and run this command:
22 *
23 * addr2line -s -e /proc/$PPID/exe -fpai {backtrace addresses} | \
24 * grep -v test_dump_stack | cat -n 1>&2
25 *
26 * Note that the spacing is different and there's no newline.
27 */
28 size_t i;
29 size_t n = 20;
30 void *stack[n];
31 const char *addr2line = "addr2line -s -e /proc/$PPID/exe -fpai";
32 const char *pipeline = "|cat -n 1>&2";
33 char cmd[strlen(addr2line) + strlen(pipeline) +
34 /* N bytes per addr * 2 digits per byte + 1 space per addr: */
35 n * (((sizeof(void *)) * 2) + 1) +
36 /* Null terminator: */
37 1];
38 char *c;
39
40 n = backtrace(stack, n);
41 c = &cmd[0];
42 c += sprintf(c, "%s", addr2line);
43 /*
44 * Skip the first 3 frames: backtrace, test_dump_stack, and
45 * test_assert. We hope that backtrace isn't inlined and the other two
46 * we've declared noinline.
47 */
48 for (i = 2; i < n; i++)
49 c += sprintf(c, " %lx", ((unsigned long) stack[i]) - 1);
50 c += sprintf(c, "%s", pipeline);
51#pragma GCC diagnostic push
52#pragma GCC diagnostic ignored "-Wunused-result"
53 system(cmd);
54#pragma GCC diagnostic pop
55}
56
57static pid_t gettid(void)
58{
59 return syscall(SYS_gettid);
60}
61
62void __attribute__((noinline))
63test_assert(bool exp, const char *exp_str,
64 const char *file, unsigned int line, const char *fmt, ...)
65{
66 va_list ap;
67
68 if (!(exp)) {
69 va_start(ap, fmt);
70
71 fprintf(stderr, "==== Test Assertion Failure ====\n"
72 " %s:%u: %s\n"
73 " pid=%d tid=%d\n",
74 file, line, exp_str, getpid(), gettid());
75 test_dump_stack();
76 if (fmt) {
77 fputs(" ", stderr);
78 vfprintf(stderr, fmt, ap);
79 fputs("\n", stderr);
80 }
81 va_end(ap);
82
83 exit(254);
84 }
85
86 return;
87}