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 
28 namespace android {
29 
30 class Worker {
31  public:
Lock()32   void Lock() {
33     mutex_.lock();
34   }
Unlock()35   void Unlock() {
36     mutex_.unlock();
37   }
38 
Signal()39   void Signal() {
40     cond_.notify_all();
41   }
42   void Exit();
43 
initialized()44   bool initialized() const {
45     return initialized_;
46   }
47 
48  protected:
49   Worker(const char *name, int priority, bool is_rt = false);
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 
should_exit()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 is_rt_;
78   bool exit_;
79   bool initialized_;
80 };
81 }  // namespace android
82 #endif
83