1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * tools/testing/selftests/kvm/lib/assert.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2018, Google LLC.
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #define _GNU_SOURCE /* for getline(3) and strchrnul(3)*/
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include "test_util.h"
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #include <execinfo.h>
13*4882a593Smuzhiyun #include <sys/syscall.h>
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun #include "kselftest.h"
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun /* Dumps the current stack trace to stderr. */
18*4882a593Smuzhiyun static void __attribute__((noinline)) test_dump_stack(void);
test_dump_stack(void)19*4882a593Smuzhiyun static void test_dump_stack(void)
20*4882a593Smuzhiyun {
21*4882a593Smuzhiyun /*
22*4882a593Smuzhiyun * Build and run this command:
23*4882a593Smuzhiyun *
24*4882a593Smuzhiyun * addr2line -s -e /proc/$PPID/exe -fpai {backtrace addresses} | \
25*4882a593Smuzhiyun * grep -v test_dump_stack | cat -n 1>&2
26*4882a593Smuzhiyun *
27*4882a593Smuzhiyun * Note that the spacing is different and there's no newline.
28*4882a593Smuzhiyun */
29*4882a593Smuzhiyun size_t i;
30*4882a593Smuzhiyun size_t n = 20;
31*4882a593Smuzhiyun void *stack[n];
32*4882a593Smuzhiyun const char *addr2line = "addr2line -s -e /proc/$PPID/exe -fpai";
33*4882a593Smuzhiyun const char *pipeline = "|cat -n 1>&2";
34*4882a593Smuzhiyun char cmd[strlen(addr2line) + strlen(pipeline) +
35*4882a593Smuzhiyun /* N bytes per addr * 2 digits per byte + 1 space per addr: */
36*4882a593Smuzhiyun n * (((sizeof(void *)) * 2) + 1) +
37*4882a593Smuzhiyun /* Null terminator: */
38*4882a593Smuzhiyun 1];
39*4882a593Smuzhiyun char *c;
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun n = backtrace(stack, n);
42*4882a593Smuzhiyun c = &cmd[0];
43*4882a593Smuzhiyun c += sprintf(c, "%s", addr2line);
44*4882a593Smuzhiyun /*
45*4882a593Smuzhiyun * Skip the first 3 frames: backtrace, test_dump_stack, and
46*4882a593Smuzhiyun * test_assert. We hope that backtrace isn't inlined and the other two
47*4882a593Smuzhiyun * we've declared noinline.
48*4882a593Smuzhiyun */
49*4882a593Smuzhiyun for (i = 2; i < n; i++)
50*4882a593Smuzhiyun c += sprintf(c, " %lx", ((unsigned long) stack[i]) - 1);
51*4882a593Smuzhiyun c += sprintf(c, "%s", pipeline);
52*4882a593Smuzhiyun #pragma GCC diagnostic push
53*4882a593Smuzhiyun #pragma GCC diagnostic ignored "-Wunused-result"
54*4882a593Smuzhiyun system(cmd);
55*4882a593Smuzhiyun #pragma GCC diagnostic pop
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun
_gettid(void)58*4882a593Smuzhiyun static pid_t _gettid(void)
59*4882a593Smuzhiyun {
60*4882a593Smuzhiyun return syscall(SYS_gettid);
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
63*4882a593Smuzhiyun void __attribute__((noinline))
test_assert(bool exp,const char * exp_str,const char * file,unsigned int line,const char * fmt,...)64*4882a593Smuzhiyun test_assert(bool exp, const char *exp_str,
65*4882a593Smuzhiyun const char *file, unsigned int line, const char *fmt, ...)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun va_list ap;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun if (!(exp)) {
70*4882a593Smuzhiyun va_start(ap, fmt);
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun fprintf(stderr, "==== Test Assertion Failure ====\n"
73*4882a593Smuzhiyun " %s:%u: %s\n"
74*4882a593Smuzhiyun " pid=%d tid=%d - %s\n",
75*4882a593Smuzhiyun file, line, exp_str, getpid(), _gettid(),
76*4882a593Smuzhiyun strerror(errno));
77*4882a593Smuzhiyun test_dump_stack();
78*4882a593Smuzhiyun if (fmt) {
79*4882a593Smuzhiyun fputs(" ", stderr);
80*4882a593Smuzhiyun vfprintf(stderr, fmt, ap);
81*4882a593Smuzhiyun fputs("\n", stderr);
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun va_end(ap);
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun if (errno == EACCES) {
86*4882a593Smuzhiyun print_skip("Access denied - Exiting");
87*4882a593Smuzhiyun exit(KSFT_SKIP);
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun exit(254);
90*4882a593Smuzhiyun }
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun return;
93*4882a593Smuzhiyun }
94