1 /* 2 * Copyright 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #pragma once 18 19 #include <mutex> 20 #include <string> 21 #include <thread> 22 23 #include "os/reactor.h" 24 #include "os/utils.h" 25 26 namespace bluetooth { 27 namespace os { 28 29 // Reactor-based looper thread implementation. The thread runs immediately after it is constructed, and stops after 30 // Stop() is invoked. To assign task to this thread, user needs to register a reactable object to the underlying 31 // reactor. 32 class Thread { 33 public: 34 // Used by thread constructor. Suggest the priority to the kernel scheduler. Use REAL_TIME if we need (soft) real-time 35 // scheduling guarantee for this thread; use NORMAL if no real-time guarantee is needed to save CPU time slice for 36 // other threads 37 enum class Priority { 38 REAL_TIME, 39 NORMAL, 40 }; 41 42 // name: thread name for POSIX systems 43 // priority: priority for kernel scheduler 44 Thread(const std::string& name, Priority priority); 45 46 // Stop and destroy this thread 47 ~Thread(); 48 49 DISALLOW_COPY_AND_ASSIGN(Thread); 50 51 // Stop this thread. Must be invoked from another thread. After this thread is stopped, it cannot be started again. 52 bool Stop(); 53 54 // Return true if this function is invoked from this thread 55 bool IsSameThread() const; 56 57 // Return the POSIX thread name 58 std::string GetThreadName() const; 59 60 // Return a user-friendly string representation of this thread object 61 std::string ToString() const; 62 63 // Return the pointer of underlying reactor. The ownership is NOT transferred. 64 Reactor* GetReactor() const; 65 66 private: 67 void run(Priority priority); 68 mutable std::mutex mutex_; 69 const std::string name_; 70 mutable Reactor reactor_; 71 std::thread running_thread_; 72 }; 73 74 } // namespace os 75 } // namespace bluetooth 76