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#include "../../kselftest.h"
17
18/* Dumps the current stack trace to stderr. */
19static void __attribute__((noinline)) test_dump_stack(void);
20static void test_dump_stack(void)
21{
22 /*
23 * Build and run this command:
24 *
25 * addr2line -s -e /proc/$PPID/exe -fpai {backtrace addresses} | \
26 * grep -v test_dump_stack | cat -n 1>&2
27 *
28 * Note that the spacing is different and there's no newline.
29 */
30 size_t i;
31 size_t n = 20;
32 void *stack[n];
33 const char *addr2line = "addr2line -s -e /proc/$PPID/exe -fpai";
34 const char *pipeline = "|cat -n 1>&2";
35 char cmd[strlen(addr2line) + strlen(pipeline) +
36 /* N bytes per addr * 2 digits per byte + 1 space per addr: */
37 n * (((sizeof(void *)) * 2) + 1) +
38 /* Null terminator: */
39 1];
40 char *c;
41
42 n = backtrace(stack, n);
43 c = &cmd[0];
44 c += sprintf(c, "%s", addr2line);
45 /*
46 * Skip the first 3 frames: backtrace, test_dump_stack, and
47 * test_assert. We hope that backtrace isn't inlined and the other two
48 * we've declared noinline.
49 */
50 for (i = 2; i < n; i++)
51 c += sprintf(c, " %lx", ((unsigned long) stack[i]) - 1);
52 c += sprintf(c, "%s", pipeline);
53#pragma GCC diagnostic push
54#pragma GCC diagnostic ignored "-Wunused-result"
55 system(cmd);
56#pragma GCC diagnostic pop
57}
58
59static pid_t gettid(void)
60{
61 return syscall(SYS_gettid);
62}
63
64void __attribute__((noinline))
65test_assert(bool exp, const char *exp_str,
66 const char *file, unsigned int line, const char *fmt, ...)
67{
68 va_list ap;
69
70 if (!(exp)) {
71 va_start(ap, fmt);
72
73 fprintf(stderr, "==== Test Assertion Failure ====\n"
74 " %s:%u: %s\n"
75 " pid=%d tid=%d - %s\n",
76 file, line, exp_str, getpid(), gettid(),
77 strerror(errno));
78 test_dump_stack();
79 if (fmt) {
80 fputs(" ", stderr);
81 vfprintf(stderr, fmt, ap);
82 fputs("\n", stderr);
83 }
84 va_end(ap);
85
86 if (errno == EACCES)
87 ksft_exit_skip("Access denied - Exiting.\n");
88 exit(254);
89 }
90
91 return;
92}