1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/at_exit.h"
#include "base/atomic_sequence_num.h"
#include "base/lazy_instance.h"
#include "base/memory/aligned_memory.h"
#include "base/threading/simple_thread.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace {
base::StaticAtomicSequenceNumber constructed_seq_;
base::StaticAtomicSequenceNumber destructed_seq_;
class ConstructAndDestructLogger {
public:
ConstructAndDestructLogger() {
constructed_seq_.GetNext();
}
~ConstructAndDestructLogger() {
destructed_seq_.GetNext();
}
};
class SlowConstructor {
public:
SlowConstructor() : some_int_(0) {
// Sleep for 1 second to try to cause a race.
base::PlatformThread::Sleep(base::TimeDelta::FromSeconds(1));
++constructed;
some_int_ = 12;
}
int some_int() const { return some_int_; }
static int constructed;
private:
int some_int_;
};
int SlowConstructor::constructed = 0;
class SlowDelegate : public base::DelegateSimpleThread::Delegate {
public:
explicit SlowDelegate(base::LazyInstance<SlowConstructor>* lazy)
: lazy_(lazy) {}
void Run() override {
EXPECT_EQ(12, lazy_->Get().some_int());
EXPECT_EQ(12, lazy_->Pointer()->some_int());
}
private:
base::LazyInstance<SlowConstructor>* lazy_;
};
} // namespace
static base::LazyInstance<ConstructAndDestructLogger> lazy_logger =
LAZY_INSTANCE_INITIALIZER;
TEST(LazyInstanceTest, Basic) {
{
base::ShadowingAtExitManager shadow;
EXPECT_EQ(0, constructed_seq_.GetNext());
EXPECT_EQ(0, destructed_seq_.GetNext());
lazy_logger.Get();
EXPECT_EQ(2, constructed_seq_.GetNext());
EXPECT_EQ(1, destructed_seq_.GetNext());
lazy_logger.Pointer();
EXPECT_EQ(3, constructed_seq_.GetNext());
EXPECT_EQ(2, destructed_seq_.GetNext());
}
EXPECT_EQ(4, constructed_seq_.GetNext());
EXPECT_EQ(4, destructed_seq_.GetNext());
}
static base::LazyInstance<SlowConstructor> lazy_slow =
LAZY_INSTANCE_INITIALIZER;
TEST(LazyInstanceTest, ConstructorThreadSafety) {
{
base::ShadowingAtExitManager shadow;
SlowDelegate delegate(&lazy_slow);
EXPECT_EQ(0, SlowConstructor::constructed);
base::DelegateSimpleThreadPool pool("lazy_instance_cons", 5);
pool.AddWork(&delegate, 20);
EXPECT_EQ(0, SlowConstructor::constructed);
pool.Start();
pool.JoinAll();
EXPECT_EQ(1, SlowConstructor::constructed);
}
}
namespace {
// DeleteLogger is an object which sets a flag when it's destroyed.
// It accepts a bool* and sets the bool to true when the dtor runs.
class DeleteLogger {
public:
DeleteLogger() : deleted_(NULL) {}
~DeleteLogger() { *deleted_ = true; }
void SetDeletedPtr(bool* deleted) {
deleted_ = deleted;
}
private:
bool* deleted_;
};
} // anonymous namespace
TEST(LazyInstanceTest, LeakyLazyInstance) {
// Check that using a plain LazyInstance causes the dtor to run
// when the AtExitManager finishes.
bool deleted1 = false;
{
base::ShadowingAtExitManager shadow;
static base::LazyInstance<DeleteLogger> test = LAZY_INSTANCE_INITIALIZER;
test.Get().SetDeletedPtr(&deleted1);
}
EXPECT_TRUE(deleted1);
// Check that using a *leaky* LazyInstance makes the dtor not run
// when the AtExitManager finishes.
bool deleted2 = false;
{
base::ShadowingAtExitManager shadow;
static base::LazyInstance<DeleteLogger>::Leaky
test = LAZY_INSTANCE_INITIALIZER;
test.Get().SetDeletedPtr(&deleted2);
}
EXPECT_FALSE(deleted2);
}
namespace {
template <size_t alignment>
class AlignedData {
public:
AlignedData() {}
~AlignedData() {}
base::AlignedMemory<alignment, alignment> data_;
};
} // anonymous namespace
#define EXPECT_ALIGNED(ptr, align) \
EXPECT_EQ(0u, reinterpret_cast<uintptr_t>(ptr) & (align - 1))
TEST(LazyInstanceTest, Alignment) {
using base::LazyInstance;
// Create some static instances with increasing sizes and alignment
// requirements. By ordering this way, the linker will need to do some work to
// ensure proper alignment of the static data.
static LazyInstance<AlignedData<4> > align4 = LAZY_INSTANCE_INITIALIZER;
static LazyInstance<AlignedData<32> > align32 = LAZY_INSTANCE_INITIALIZER;
static LazyInstance<AlignedData<4096> > align4096 = LAZY_INSTANCE_INITIALIZER;
EXPECT_ALIGNED(align4.Pointer(), 4);
EXPECT_ALIGNED(align32.Pointer(), 32);
EXPECT_ALIGNED(align4096.Pointer(), 4096);
}
|