AAudioThread.h revision 5ed503c7a66c90f93759c90237a9b432dbd93f9f 
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
17#ifndef AAUDIO_THREAD_H
18#define AAUDIO_THREAD_H
19
20#include <atomic>
21#include <pthread.h>
22
23#include <aaudio/AAudioDefinitions.h>
24
25namespace aaudio {
26
27class Runnable {
28public:
29    Runnable() {};
30    virtual ~Runnable() = default;
31
32    virtual void run() {}
33};
34
35/**
36 * Abstraction for a host thread.
37 */
38class AAudioThread
39{
40public:
41    AAudioThread();
42    AAudioThread(Runnable *runnable);
43    virtual ~AAudioThread() = default;
44
45    /**
46     * Start the thread running.
47     */
48    aaudio_result_t start(Runnable *runnable = nullptr);
49
50    /**
51     * Join the thread.
52     * The caller must somehow tell the thread to exit before calling join().
53     */
54    aaudio_result_t stop();
55
56    /**
57     * This will get called in the thread.
58     * Override this or pass a Runnable to start().
59     */
60    virtual void run() {};
61
62    void dispatch(); // called internally from 'C' thread wrapper
63
64private:
65    Runnable*                mRunnable = nullptr; // TODO make atomic with memory barrier?
66    bool                     mHasThread = false;
67    pthread_t                mThread; // initialized in constructor
68
69};
70
71} /* namespace aaudio */
72
73#endif ///AAUDIO_THREAD_H
74