1/*
2 * Copyright (C) 2015-2016 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
17#ifndef ANDROID_WORKER_H_
18#define ANDROID_WORKER_H_
19
20#include <stdint.h>
21#include <stdlib.h>
22#include <string>
23
24#include <condition_variable>
25#include <mutex>
26#include <thread>
27
28namespace android {
29
30class Worker {
31 public:
32  void Lock() {
33    mutex_.lock();
34  }
35  void Unlock() {
36    mutex_.unlock();
37  }
38
39  void Signal() {
40    cond_.notify_all();
41  }
42  void Exit();
43
44  bool initialized() const {
45    return initialized_;
46  }
47
48 protected:
49  Worker(const char *name, int priority);
50  virtual ~Worker();
51
52  int InitWorker();
53  virtual void Routine() = 0;
54
55  /*
56   * Must be called with the lock acquired. max_nanoseconds may be negative to
57   * indicate infinite timeout, otherwise it indicates the maximum time span to
58   * wait for a signal before returning.
59   * Returns -EINTR if interrupted by exit request, or -ETIMEDOUT if timed out
60   */
61  int WaitForSignalOrExitLocked(int64_t max_nanoseconds = -1);
62
63  bool should_exit() const {
64    return exit_;
65  }
66
67  std::mutex mutex_;
68  std::condition_variable cond_;
69
70 private:
71  void InternalRoutine();
72
73  std::string name_;
74  int priority_;
75
76  std::unique_ptr<std::thread> thread_;
77  bool exit_;
78  bool initialized_;
79};
80}
81#endif
82