1/* 2 * Copyright (C) 2016 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#ifndef ANDROID_HIDL_TASK_RUNNER_H 17#define ANDROID_HIDL_TASK_RUNNER_H 18 19#include "SynchronizedQueue.h" 20#include <memory> 21#include <thread> 22 23namespace android { 24namespace hardware { 25namespace details { 26 27/* 28 * A background infinite loop that runs the Tasks push()'ed. 29 * Equivalent to a simple single-threaded Looper. 30 */ 31class TaskRunner { 32public: 33 using Task = std::function<void(void)>; 34 35 /* Create an empty task runner. Nothing will be done until start() is called. */ 36 TaskRunner(); 37 38 /* 39 * Notify the background thread to terminate and return immediately. 40 * Tasks in the queue will continue to be done sequentially in background 41 * until all tasks are finished. 42 */ 43 ~TaskRunner(); 44 45 /* 46 * Sets the queue limit. Fails the push operation once the limit is reached. 47 * Then kicks off the loop. 48 */ 49 void start(size_t limit); 50 51 /* 52 * Add a task. Return true if successful, false if 53 * the queue's size exceeds limit or t doesn't contain a callable target. 54 */ 55 bool push(const Task &t); 56 57private: 58 std::shared_ptr<SynchronizedQueue<Task>> mQueue; 59}; 60 61} // namespace details 62} // namespace hardware 63} // namespace android 64 65#endif // ANDROID_HIDL_TASK_RUNNER_H 66