1 /*
2  * Copyright (C) 2015 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 MEDIA_CLOCK_H_
18 
19 #define MEDIA_CLOCK_H_
20 
21 #include <list>
22 #include <media/stagefright/foundation/AHandler.h>
23 #include <utils/Mutex.h>
24 #include <utils/RefBase.h>
25 
26 namespace android {
27 
28 struct AMessage;
29 
30 struct MediaClock : public AHandler {
31     enum {
32         TIMER_REASON_REACHED = 0,
33         TIMER_REASON_RESET = 1,
34     };
35 
36     MediaClock();
37     void init();
38 
39     void setStartingTimeMedia(int64_t startingTimeMediaUs);
40 
41     void clearAnchor();
42     // It's required to use timestamp of just rendered frame as
43     // anchor time in paused state.
44     void updateAnchor(
45             int64_t anchorTimeMediaUs,
46             int64_t anchorTimeRealUs,
47             int64_t maxTimeMediaUs = INT64_MAX);
48 
49     void updateMaxTimeMedia(int64_t maxTimeMediaUs);
50 
51     void setPlaybackRate(float rate);
52     float getPlaybackRate() const;
53 
54     // query media time corresponding to real time |realUs|, and save the
55     // result in |outMediaUs|.
56     status_t getMediaTime(
57             int64_t realUs,
58             int64_t *outMediaUs,
59             bool allowPastMaxTime = false) const;
60     // query real time corresponding to media time |targetMediaUs|.
61     // The result is saved in |outRealUs|.
62     status_t getRealTimeFor(int64_t targetMediaUs, int64_t *outRealUs) const;
63 
64     // request to set up a timer. The target time is |mediaTimeUs|, adjusted by
65     // system time of |adjustRealUs|. In other words, the wake up time is
66     // mediaTimeUs + (adjustRealUs / playbackRate)
67     void addTimer(const sp<AMessage> &notify, int64_t mediaTimeUs, int64_t adjustRealUs = 0);
68 
69     void setNotificationMessage(const sp<AMessage> &msg);
70 
71     void reset();
72 
73 protected:
74     virtual ~MediaClock();
75 
76     virtual void onMessageReceived(const sp<AMessage> &msg);
77 
78 private:
79     enum {
80         kWhatTimeIsUp = 'tIsU',
81     };
82 
83     struct Timer {
84         Timer(const sp<AMessage> &notify, int64_t mediaTimeUs, int64_t adjustRealUs);
85         const sp<AMessage> mNotify;
86         int64_t mMediaTimeUs;
87         int64_t mAdjustRealUs;
88     };
89 
90     status_t getMediaTime_l(
91             int64_t realUs,
92             int64_t *outMediaUs,
93             bool allowPastMaxTime) const;
94 
95     void processTimers_l();
96 
97     void updateAnchorTimesAndPlaybackRate_l(
98             int64_t anchorTimeMediaUs, int64_t anchorTimeRealUs , float playbackRate);
99 
100     void notifyDiscontinuity_l();
101 
102     sp<ALooper> mLooper;
103     mutable Mutex mLock;
104 
105     int64_t mAnchorTimeMediaUs;
106     int64_t mAnchorTimeRealUs;
107     int64_t mMaxTimeMediaUs;
108     int64_t mStartingTimeMediaUs;
109 
110     float mPlaybackRate;
111 
112     int32_t mGeneration;
113     std::list<Timer> mTimers;
114     sp<AMessage> mNotify;
115 
116     DISALLOW_EVIL_CONSTRUCTORS(MediaClock);
117 };
118 
119 }  // namespace android
120 
121 #endif  // MEDIA_CLOCK_H_
122