getauxval_test.cpp revision a65a3ad837618c5bf5c0b798bf9217a509ab5c61 
1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <errno.h>
18#include <sys/cdefs.h>
19#include <gtest/gtest.h>
20
21// getauxval() was only added as of glibc version 2.16.
22// See: http://lwn.net/Articles/519085/
23// Don't try to compile this code on older glibc versions.
24
25#if defined(__BIONIC__)
26  #define GETAUXVAL_CAN_COMPILE 1
27#elif defined(__GLIBC_PREREQ)
28  #if __GLIBC_PREREQ(2, 16)
29    #define GETAUXVAL_CAN_COMPILE 1
30  #endif
31#endif
32
33#if defined(GETAUXVAL_CAN_COMPILE)
34#include <sys/auxv.h>
35#endif
36
37TEST(getauxval, expected_values) {
38#if defined(GETAUXVAL_CAN_COMPILE)
39  ASSERT_EQ(0UL, getauxval(AT_SECURE));
40  ASSERT_EQ(getuid(), getauxval(AT_UID));
41  ASSERT_EQ(geteuid(), getauxval(AT_EUID));
42  ASSERT_EQ(getgid(), getauxval(AT_GID));
43  ASSERT_EQ(getegid(), getauxval(AT_EGID));
44  ASSERT_EQ(static_cast<unsigned long>(getpagesize()), getauxval(AT_PAGESZ));
45
46  ASSERT_NE(0UL, getauxval(AT_PHDR));
47  ASSERT_NE(0UL, getauxval(AT_PHNUM));
48  ASSERT_NE(0UL, getauxval(AT_ENTRY));
49  ASSERT_NE(0UL, getauxval(AT_PAGESZ));
50#else
51  GTEST_LOG_(INFO) << "This test requires a C library with getauxval.\n";
52#endif
53}
54
55TEST(getauxval, unexpected_values) {
56#if defined(GETAUXVAL_CAN_COMPILE)
57  errno = 0;
58  ASSERT_EQ(0UL, getauxval(0xdeadbeef));
59  ASSERT_EQ(ENOENT, errno);
60#else
61  GTEST_LOG_(INFO) << "This test requires a C library with getauxval.\n";
62#endif
63}
64
65TEST(getauxval, arm_has_AT_HWCAP2) {
66#if defined(__arm__)
67  // If this test fails, apps that use getauxval to decide at runtime whether crypto hardware is
68  // available will incorrectly assume that it isn't, and will have really bad performance.
69  // If this test fails, ensure that you've enabled COMPAT_BINFMT_ELF in your kernel configuration.
70  ASSERT_NE(0UL, getauxval(AT_HWCAP2)) << "kernel not reporting AT_HWCAP2 to 32-bit ARM process";
71#else
72  GTEST_LOG_(INFO) << "This test is only meaningful for 32-bit ARM code.\n";
73#endif
74}
75