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// Copyright (c) 2008 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/simple_thread.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace {
base::AtomicSequenceNumber constructed_seq_(base::LINKER_INITIALIZED);
base::AtomicSequenceNumber destructed_seq_(base::LINKER_INITIALIZED);
class ConstructAndDestructLogger {
public:
ConstructAndDestructLogger() {
constructed_seq_.GetNext();
}
~ConstructAndDestructLogger() {
destructed_seq_.GetNext();
}
};
class SlowConstructor {
public:
SlowConstructor() : some_int_(0) {
PlatformThread::Sleep(1000); // Sleep for 1 second to try to cause a race.
++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) {}
virtual void Run() {
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(
base::LINKER_INITIALIZED);
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(base::LINKER_INITIALIZED);
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);
}
}
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