| /****************************************************************************** |
| * |
| * Copyright 2020 Google, Inc. |
| * |
| * 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 <mutex> |
| #include <string> |
| #include <thread> |
| #include <unordered_set> |
| #include "raw_address.h" |
| |
| #include "lru.h" |
| |
| namespace bluetooth { |
| |
| namespace common { |
| |
| class MetricIdAllocator { |
| public: |
| using Callback = std::function<bool(const RawAddress& address, const int id)>; |
| |
| static const size_t kMaxNumUnpairedDevicesInMemory; |
| static const size_t kMaxNumPairedDevicesInMemory; |
| |
| static const int kMinId; |
| static const int kMaxId; |
| |
| ~MetricIdAllocator(); |
| |
| /** |
| * Get the instance of singleton |
| * |
| * @return MetricIdAllocator& |
| */ |
| static MetricIdAllocator& GetInstance(); |
| |
| /** |
| * Initialize the allocator |
| * |
| * @param paired_device_map map from mac_address to id already saved |
| * in the disk before init |
| * @param save_id_callback a callback that will be called after successfully |
| * saving id for a paired device |
| * @param forget_device_callback a callback that will be called after |
| * successful id deletion for forgotten device, |
| * @return true if successfully initialized |
| */ |
| bool Init(const std::unordered_map<RawAddress, int>& paired_device_map, |
| Callback save_id_callback, Callback forget_device_callback); |
| |
| /** |
| * Close the allocator. should be called when Bluetooth process is killed |
| * |
| * @return true if successfully close |
| */ |
| bool Close(); |
| |
| /** |
| * Check if no id saved in memory |
| * |
| * @return true if no id is saved |
| */ |
| bool IsEmpty() const; |
| |
| /** |
| * Allocate an id for a scanned device, or return the id if there is already |
| * one |
| * |
| * @param mac_address mac address of Bluetooth device |
| * @return the id of device |
| */ |
| int AllocateId(const RawAddress& mac_address); |
| |
| /** |
| * Save the id for a paired device |
| * |
| * @param mac_address mac address of Bluetooth device |
| * @return true if save successfully |
| */ |
| bool SaveDevice(const RawAddress& mac_address); |
| |
| /** |
| * Delete the id for a device to be forgotten |
| * |
| * @param mac_address mac address of Bluetooth device |
| */ |
| void ForgetDevice(const RawAddress& mac_address); |
| |
| /** |
| * Check if an id is valid. |
| * The id should be less than or equal to kMaxId and bigger than or equal to |
| * kMinId |
| * |
| * @param mac_address mac address of Bluetooth device |
| * @return true if delete successfully |
| */ |
| static bool IsValidId(const int id); |
| |
| protected: |
| // Singleton |
| MetricIdAllocator(); |
| |
| private: |
| static const std::string LOGGING_TAG; |
| mutable std::mutex id_allocator_mutex_; |
| |
| LruCache<RawAddress, int> paired_device_cache_; |
| LruCache<RawAddress, int> temporary_device_cache_; |
| std::unordered_set<int> id_set_; |
| |
| int next_id_{kMinId}; |
| bool initialized_{false}; |
| Callback save_id_callback_; |
| Callback forget_device_callback_; |
| |
| void ForgetDevicePostprocess(const RawAddress& mac_address, const int id); |
| |
| // delete copy constructor for singleton |
| MetricIdAllocator(MetricIdAllocator const&) = delete; |
| MetricIdAllocator& operator=(MetricIdAllocator const&) = delete; |
| }; |
| |
| } // namespace common |
| } // namespace bluetooth |