1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * vdso_test_gettimeofday.c: Sample code to test parse_vdso.c and
4 * vDSO gettimeofday()
5 * Copyright (c) 2014 Andy Lutomirski
6 *
7 * Compile with:
8 * gcc -std=gnu99 vdso_test_gettimeofday.c parse_vdso_gettimeofday.c
9 *
10 * Tested on x86, 32-bit and 64-bit. It may work on other architectures, too.
11 */
12
13 #include <stdint.h>
14 #include <elf.h>
15 #include <stdio.h>
16 #include <sys/auxv.h>
17 #include <sys/time.h>
18
19 #include "../kselftest.h"
20 #include "parse_vdso.h"
21 #include "vdso_config.h"
22
23 int main(int argc, char **argv)
24 {
25 const char *version = versions[VDSO_VERSION];
26 const char **name = (const char **)&names[VDSO_NAMES];
27
28 unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
29 if (!sysinfo_ehdr) {
30 printf("AT_SYSINFO_EHDR is not present!\n");
31 return KSFT_SKIP;
32 }
33
34 vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
35
36 /* Find gettimeofday. */
37 typedef long (*gtod_t)(struct timeval *tv, struct timezone *tz);
38 gtod_t gtod = (gtod_t)vdso_sym(version, name[0]);
39
40 if (!gtod) {
41 printf("Could not find %s\n", name[0]);
42 return KSFT_SKIP;
43 }
44
45 struct timeval tv;
46 long ret = gtod(&tv, 0);
47
48 if (ret == 0) {
49 printf("The time is %lld.%06lld\n",
50 (long long)tv.tv_sec, (long long)tv.tv_usec);
51 } else {
52 printf("%s failed\n", name[0]);
53 return KSFT_FAIL;
54 }
55
56 return 0;
57 }
58
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