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 <stdlib.h>
18#include <string.h>
19#include <sys/mman.h>
20
21#include <gtest/gtest.h>
22
23#include "../linker_allocator.h"
24
25#include <unistd.h>
26
27namespace {
28
29struct test_struct_nominal {
30  void* pointer;
31  ssize_t value;
32};
33
34/*
35 * this one has size below allocator cap which is 2*sizeof(void*)
36 */
37struct test_struct_small {
38  char dummy_str[5];
39};
40
41/*
42 * 1009 byte struct (1009 is prime)
43 */
44struct test_struct_larger {
45  char dummy_str[1009];
46};
47
48static size_t kPageSize = sysconf(_SC_PAGE_SIZE);
49};
50
51TEST(linker_allocator, test_nominal) {
52  LinkerAllocator<test_struct_nominal> allocator;
53
54  test_struct_nominal* ptr1 = allocator.alloc();
55  ASSERT_TRUE(ptr1 != nullptr);
56  test_struct_nominal* ptr2 = allocator.alloc();
57  ASSERT_TRUE(ptr2 != nullptr);
58  // they should be next to each other.
59  ASSERT_EQ(ptr1+1, ptr2);
60
61  ptr1->value = 42;
62
63  allocator.free(ptr1);
64  allocator.free(ptr2);
65}
66
67TEST(linker_allocator, test_small) {
68  LinkerAllocator<test_struct_small> allocator;
69
70  char* ptr1 = reinterpret_cast<char*>(allocator.alloc());
71  char* ptr2 = reinterpret_cast<char*>(allocator.alloc());
72
73  ASSERT_TRUE(ptr1 != nullptr);
74  ASSERT_TRUE(ptr2 != nullptr);
75  ASSERT_EQ(ptr1+2*sizeof(void*), ptr2);
76}
77
78TEST(linker_allocator, test_larger) {
79  LinkerAllocator<test_struct_larger> allocator;
80
81  test_struct_larger* ptr1 = allocator.alloc();
82  test_struct_larger* ptr2 = allocator.alloc();
83
84  ASSERT_TRUE(ptr1 != nullptr);
85  ASSERT_TRUE(ptr2 != nullptr);
86
87  ASSERT_EQ(ptr1+1, ptr2);
88
89  // lets allocate until we reach next page.
90  size_t n = kPageSize/sizeof(test_struct_larger) + 1 - 2;
91
92  for (size_t i=0; i<n; ++i) {
93    ASSERT_TRUE(allocator.alloc() != nullptr);
94  }
95
96  test_struct_larger* ptr_to_free = allocator.alloc();
97  ASSERT_TRUE(ptr_to_free != nullptr);
98  allocator.free(ptr1);
99}
100
101static void protect_all() {
102  LinkerAllocator<test_struct_larger> allocator;
103
104  // number of allocs to reach the end of first page
105  size_t n = kPageSize/sizeof(test_struct_larger) - 1;
106  test_struct_larger* page1_ptr = allocator.alloc();
107
108  for (size_t i=0; i<n; ++i) {
109    allocator.alloc();
110  }
111
112  test_struct_larger* page2_ptr = allocator.alloc();
113  allocator.protect_all(PROT_READ);
114  allocator.protect_all(PROT_READ | PROT_WRITE);
115  // check access
116  page2_ptr->dummy_str[23] = 27;
117  page1_ptr->dummy_str[13] = 11;
118
119  allocator.protect_all(PROT_READ);
120  fprintf(stderr, "trying to access protected page");
121
122  // this should result in segmentation fault
123  page1_ptr->dummy_str[11] = 7;
124}
125
126TEST(linker_allocator, test_protect) {
127  testing::FLAGS_gtest_death_test_style = "threadsafe";
128  ASSERT_EXIT(protect_all(), testing::KilledBySignal(SIGSEGV), "trying to access protected page");
129}
130
131