TrackBase.h revision 462fd2fa9eef642b0574aa7409de0bde3fec8d43 
1/*
2**
3** Copyright 2012, The Android Open Source Project
4**
5** Licensed under the Apache License, Version 2.0 (the "License");
6** you may not use this file except in compliance with the License.
7** You may obtain a copy of the License at
8**
9**     http://www.apache.org/licenses/LICENSE-2.0
10**
11** Unless required by applicable law or agreed to in writing, software
12** distributed under the License is distributed on an "AS IS" BASIS,
13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14** See the License for the specific language governing permissions and
15** limitations under the License.
16*/
17
18#ifndef INCLUDING_FROM_AUDIOFLINGER_H
19    #error This header file should only be included from AudioFlinger.h
20#endif
21
22// base for record and playback
23class TrackBase : public ExtendedAudioBufferProvider, public RefBase {
24
25public:
26    enum track_state {
27        IDLE,
28        FLUSHED,
29        STOPPED,
30        // next 2 states are currently used for fast tracks
31        // and offloaded tracks only
32        STOPPING_1,     // waiting for first underrun
33        STOPPING_2,     // waiting for presentation complete
34        RESUMING,
35        ACTIVE,
36        PAUSING,
37        PAUSED
38    };
39
40                        TrackBase(ThreadBase *thread,
41                                const sp<Client>& client,
42                                uint32_t sampleRate,
43                                audio_format_t format,
44                                audio_channel_mask_t channelMask,
45                                size_t frameCount,
46                                const sp<IMemory>& sharedBuffer,
47                                int sessionId,
48                                int uid,
49                                bool isOut);
50    virtual             ~TrackBase();
51    virtual status_t    initCheck() const { return getCblk() != 0 ? NO_ERROR : NO_MEMORY; }
52
53    virtual status_t    start(AudioSystem::sync_event_t event,
54                             int triggerSession) = 0;
55    virtual void        stop() = 0;
56            sp<IMemory> getCblk() const { return mCblkMemory; }
57            audio_track_cblk_t* cblk() const { return mCblk; }
58            int         sessionId() const { return mSessionId; }
59            int         uid() const { return mUid; }
60    virtual status_t    setSyncEvent(const sp<SyncEvent>& event);
61
62protected:
63                        TrackBase(const TrackBase&);
64                        TrackBase& operator = (const TrackBase&);
65
66    // AudioBufferProvider interface
67    virtual status_t getNextBuffer(AudioBufferProvider::Buffer* buffer, int64_t pts) = 0;
68    virtual void releaseBuffer(AudioBufferProvider::Buffer* buffer);
69
70    // ExtendedAudioBufferProvider interface is only needed for Track,
71    // but putting it in TrackBase avoids the complexity of virtual inheritance
72    virtual size_t  framesReady() const { return SIZE_MAX; }
73
74    audio_format_t format() const { return mFormat; }
75
76    uint32_t channelCount() const { return mChannelCount; }
77
78    audio_channel_mask_t channelMask() const { return mChannelMask; }
79
80    virtual uint32_t sampleRate() const { return mSampleRate; }
81
82    bool isStopped() const {
83        return (mState == STOPPED || mState == FLUSHED);
84    }
85
86    // for fast tracks and offloaded tracks only
87    bool isStopping() const {
88        return mState == STOPPING_1 || mState == STOPPING_2;
89    }
90    bool isStopping_1() const {
91        return mState == STOPPING_1;
92    }
93    bool isStopping_2() const {
94        return mState == STOPPING_2;
95    }
96
97    bool isTerminated() const {
98        return mTerminated;
99    }
100
101    void terminate() {
102        mTerminated = true;
103    }
104
105    bool isOut() const { return mIsOut; }
106                                    // true for Track and TimedTrack, false for RecordTrack,
107                                    // this could be a track type if needed later
108
109    const wp<ThreadBase> mThread;
110    /*const*/ sp<Client> mClient;   // see explanation at ~TrackBase() why not const
111    sp<IMemory>         mCblkMemory;
112    audio_track_cblk_t* mCblk;
113    void*               mBuffer;    // start of track buffer, typically in shared memory
114                                    // except for OutputTrack when it is in local memory
115    // we don't really need a lock for these
116    track_state         mState;
117    const uint32_t      mSampleRate;    // initial sample rate only; for tracks which
118                        // support dynamic rates, the current value is in control block
119    const audio_format_t mFormat;
120    const audio_channel_mask_t mChannelMask;
121    const uint32_t      mChannelCount;
122    const size_t        mFrameSize; // AudioFlinger's view of frame size in shared memory,
123                                    // where for AudioTrack (but not AudioRecord),
124                                    // 8-bit PCM samples are stored as 16-bit
125    const size_t        mFrameCount;// size of track buffer given at createTrack() or
126                                    // openRecord(), and then adjusted as needed
127
128    const int           mSessionId;
129    int                 mUid;
130    Vector < sp<SyncEvent> >mSyncEvents;
131    const bool          mIsOut;
132    ServerProxy*        mServerProxy;
133    const int           mId;
134    sp<NBAIO_Sink>      mTeeSink;
135    sp<NBAIO_Source>    mTeeSource;
136    bool                mTerminated;
137};
138