Merge "Add android::base::ScopeGuard"

        "parseint_test.cpp",

        "parsenetaddress_test.cpp",

        "quick_exit_test.cpp",

        "scopeguard_test.cpp",

        "stringprintf_test.cpp",

        "strings_test.cpp",

        "test_main.cpp",

/*

 * Copyright (C) 2014 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#ifndef ANDROID_BASE_SCOPEGUARD_H

#define ANDROID_BASE_SCOPEGUARD_H

#include <utility>  // for std::move

namespace android {

namespace base {

template <typename F>

class ScopeGuard {

 public:

  ScopeGuard(F f) : f_(f), active_(true) {}

  ScopeGuard(ScopeGuard&& that) : f_(std::move(that.f_)), active_(that.active_) {

    that.active_ = false;

  }

  ~ScopeGuard() {

    if (active_) f_();

  }

  ScopeGuard() = delete;

  ScopeGuard(const ScopeGuard&) = delete;

  void operator=(const ScopeGuard&) = delete;

  void operator=(ScopeGuard&& that) = delete;

  void Disable() { active_ = false; }

  bool active() const { return active_; }

 private:

  F f_;

  bool active_;

};

template <typename T>

ScopeGuard<T> make_scope_guard(T f) {

  return ScopeGuard<T>(f);

}

}  // namespace base

}  // namespace android

#endif  // ANDROID_BASE_SCOPEGUARD_H

/*

 * Copyright (C) 2017 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include "android-base/scopeguard.h"

#include <utility>

#include <gtest/gtest.h>

TEST(scopeguard, normal) {

  bool guarded_var = true;

  {

    auto scopeguard = android::base::make_scope_guard([&guarded_var] { guarded_var = false; });

  }

  ASSERT_FALSE(guarded_var);

}

TEST(scopeguard, disabled) {

  bool guarded_var = true;

  {

    auto scopeguard = android::base::make_scope_guard([&guarded_var] { guarded_var = false; });

    scopeguard.Disable();

  }

  ASSERT_TRUE(guarded_var);

}

TEST(scopeguard, moved) {

  int guarded_var = true;

  auto scopeguard = android::base::make_scope_guard([&guarded_var] { guarded_var = false; });

  { decltype(scopeguard) new_guard(std::move(scopeguard)); }

  EXPECT_FALSE(scopeguard.active());

  ASSERT_FALSE(guarded_var);

}