Line data    Source code

       1              : /*
       2              :  * If not stated otherwise in this file or this component's LICENSE file the
       3              :  * following copyright and licenses apply:
       4              :  *
       5              :  * Copyright 2022 Sky UK
       6              :  *
       7              :  * Licensed under the Apache License, Version 2.0 (the "License");
       8              :  * you may not use this file except in compliance with the License.
       9              :  * You may obtain a copy of the License at
      10              :  *
      11              :  * http://www.apache.org/licenses/LICENSE-2.0
      12              :  *
      13              :  * Unless required by applicable law or agreed to in writing, software
      14              :  * distributed under the License is distributed on an "AS IS" BASIS,
      15              :  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      16              :  * See the License for the specific language governing permissions and
      17              :  * limitations under the License.
      18              :  */
      19              : 
      20              : #ifndef FIREBOLT_RIALTO_SERVER_MAIN_THREAD_H_
      21              : #define FIREBOLT_RIALTO_SERVER_MAIN_THREAD_H_
      22              : 
      23              : #include "IMainThread.h"
      24              : #include <atomic>
      25              : #include <condition_variable>
      26              : #include <deque>
      27              : #include <map>
      28              : #include <memory>
      29              : #include <mutex>
      30              : #include <set>
      31              : #include <string>
      32              : #include <thread>
      33              : 
      34              : namespace firebolt::rialto::server
      35              : {
      36              : /**
      37              :  * @brief IMainThread factory class definition.
      38              :  */
      39              : class MainThreadFactory : public IMainThreadFactory
      40              : {
      41              : public:
      42           28 :     MainThreadFactory() = default;
      43           28 :     ~MainThreadFactory() override = default;
      44              : 
      45              :     std::shared_ptr<IMainThread> getMainThread() const override;
      46              : 
      47              : protected:
      48              :     /**
      49              :      * @brief Weak pointer to the singleton main thread object.
      50              :      */
      51              :     static std::weak_ptr<IMainThread> m_mainThread;
      52              : 
      53              :     /**
      54              :      * @brief Mutex protection for creation of the MainThread object.
      55              :      */
      56              :     static std::mutex m_creationMutex;
      57              : };
      58              : 
      59              : /**
      60              :  * @brief The definition of the MediaKeys.
      61              :  */
      62              : class MainThread : public IMainThread
      63              : {
      64              : public:
      65              :     MainThread();
      66              :     virtual ~MainThread();
      67              : 
      68              :     int32_t registerClient() override;
      69              :     void unregisterClient(uint32_t clientId) override;
      70              : 
      71              :     void enqueueTask(uint32_t clientId, const Task &task) override;
      72              :     void enqueueTaskAndWait(uint32_t clientId, const Task &task) override;
      73              :     void enqueuePriorityTaskAndWait(uint32_t clientId, const Task &task) override;
      74              : 
      75              : private:
      76              :     /**
      77              :      * @brief Information of a task.
      78              :      */
      79              :     struct TaskInfo
      80              :     {
      81              :         bool done{false};                            /**< A flag indicating whether the task has completed. */
      82              :         uint32_t clientId;                           /**< The id of the client creating the task. */
      83              :         Task task;                                   /**< The task to execute. */
      84              :         std::unique_ptr<std::mutex> mutex;           /**< Mutex for the task condition variable. */
      85              :         std::unique_ptr<std::condition_variable> cv; /**< The condition variable of the task. */
      86              :     };
      87              : 
      88              :     /**
      89              :      * @brief Starts a loop that listens for enqueued tasks.
      90              :      */
      91              :     void mainThreadLoop();
      92              : 
      93              :     /**
      94              :      * @brief Waits for tasks to enter the queue and returns the next task.
      95              :      *
      96              :      * @retval The next task in the queue.
      97              :      */
      98              :     const std::shared_ptr<TaskInfo> waitForTask();
      99              : 
     100              :     /**
     101              :      * @brief Whether the main thread is running.
     102              :      */
     103              :     bool m_isMainThreadRunning;
     104              : 
     105              :     /**
     106              :      * @brief The main thread.
     107              :      */
     108              :     std::thread m_thread;
     109              : 
     110              :     /**
     111              :      * @brief A mutex protecting access to the task queue.
     112              :      */
     113              :     std::mutex m_taskQueueMutex;
     114              : 
     115              :     /**
     116              :      * @brief A condition variable used to notify of tasks entering the task queue.
     117              :      */
     118              :     std::condition_variable m_taskQueueCv;
     119              : 
     120              :     /**
     121              :      * @brief The queue of tasks and there infomation.
     122              :      */
     123              :     std::deque<std::shared_ptr<TaskInfo>> m_taskQueue;
     124              : 
     125              :     /**
     126              :      * @brief The main thread objects client id, for registering new clients.
     127              :      */
     128              :     const uint32_t m_mainThreadClientId;
     129              : 
     130              :     /**
     131              :      * @brief The next client id to be given to a registering client.
     132              :      */
     133              :     std::atomic<uint32_t> m_nextClientId;
     134              : 
     135              :     /**
     136              :      * @brief Clients registered on this thread.
     137              :      */
     138              :     std::set<uint32_t> m_registeredClients;
     139              : };
     140              : } // namespace firebolt::rialto::server
     141              : 
     142              : #endif // FIREBOLT_RIALTO_SERVER_MAIN_THREAD_H_