base/include/android-base/errno_restorer.h

/*
 * Copyright (C) 2020 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.
 */

#pragma once

#include "errno.h"

#include "android-base/macros.h"

namespace android {
namespace base {

class ErrnoRestorer {
 public:
  ErrnoRestorer() : saved_errno_(errno) {}

  ~ErrnoRestorer() { errno = saved_errno_; }

  // Allow this object to be used as part of && operation.
  operator bool() const { return true; }

 private:
  const int saved_errno_;

  DISALLOW_COPY_AND_ASSIGN(ErrnoRestorer);
};

}  // namespace base
}  // namespace android