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12#include <stdint.h>
13#include <elf.h>
14#include <stdio.h>
15#include <sys/auxv.h>
16#include <sys/time.h>
17
18#include "../kselftest.h"
19
20extern void *vdso_sym(const char *version, const char *name);
21extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);
22extern void vdso_init_from_auxv(void *auxv);
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29#if defined(__aarch64__)
30const char *version = "LINUX_2.6.39";
31const char *name = "__kernel_gettimeofday";
32#else
33const char *version = "LINUX_2.6";
34const char *name = "__vdso_gettimeofday";
35#endif
36
37int main(int argc, char **argv)
38{
39 unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
40 if (!sysinfo_ehdr) {
41 printf("AT_SYSINFO_EHDR is not present!\n");
42 return KSFT_SKIP;
43 }
44
45 vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
46
47
48 typedef long (*gtod_t)(struct timeval *tv, struct timezone *tz);
49 gtod_t gtod = (gtod_t)vdso_sym(version, name);
50
51 if (!gtod) {
52 printf("Could not find %s\n", name);
53 return KSFT_SKIP;
54 }
55
56 struct timeval tv;
57 long ret = gtod(&tv, 0);
58
59 if (ret == 0) {
60 printf("The time is %lld.%06lld\n",
61 (long long)tv.tv_sec, (long long)tv.tv_usec);
62 } else {
63 printf("%s failed\n", name);
64 return KSFT_FAIL;
65 }
66
67 return 0;
68}
69