AudioTrack.cpp revision 0ca3cf94c0dfc173ad7886ae162c4b67067539f6 
1/*
2**
3** Copyright 2007, 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
19//#define LOG_NDEBUG 0
20#define LOG_TAG "AudioTrack"
21
22#include <stdint.h>
23#include <sys/types.h>
24#include <limits.h>
25
26#include <sched.h>
27#include <sys/resource.h>
28
29#include <private/media/AudioTrackShared.h>
30
31#include <media/AudioSystem.h>
32#include <media/AudioTrack.h>
33
34#include <utils/Log.h>
35#include <binder/Parcel.h>
36#include <binder/IPCThreadState.h>
37#include <utils/Timers.h>
38#include <utils/Atomic.h>
39
40#include <cutils/bitops.h>
41#include <cutils/compiler.h>
42
43#include <system/audio.h>
44#include <system/audio_policy.h>
45
46#include <audio_utils/primitives.h>
47
48namespace android {
49// ---------------------------------------------------------------------------
50
51// static
52status_t AudioTrack::getMinFrameCount(
53        int* frameCount,
54        audio_stream_type_t streamType,
55        uint32_t sampleRate)
56{
57    int afSampleRate;
58    if (AudioSystem::getOutputSamplingRate(&afSampleRate, streamType) != NO_ERROR) {
59        return NO_INIT;
60    }
61    int afFrameCount;
62    if (AudioSystem::getOutputFrameCount(&afFrameCount, streamType) != NO_ERROR) {
63        return NO_INIT;
64    }
65    uint32_t afLatency;
66    if (AudioSystem::getOutputLatency(&afLatency, streamType) != NO_ERROR) {
67        return NO_INIT;
68    }
69
70    // Ensure that buffer depth covers at least audio hardware latency
71    uint32_t minBufCount = afLatency / ((1000 * afFrameCount) / afSampleRate);
72    if (minBufCount < 2) minBufCount = 2;
73
74    *frameCount = (sampleRate == 0) ? afFrameCount * minBufCount :
75            afFrameCount * minBufCount * sampleRate / afSampleRate;
76    return NO_ERROR;
77}
78
79// ---------------------------------------------------------------------------
80
81AudioTrack::AudioTrack()
82    : mStatus(NO_INIT),
83      mIsTimed(false),
84      mPreviousPriority(ANDROID_PRIORITY_NORMAL),
85      mPreviousSchedulingGroup(ANDROID_TGROUP_DEFAULT)
86{
87}
88
89AudioTrack::AudioTrack(
90        audio_stream_type_t streamType,
91        uint32_t sampleRate,
92        audio_format_t format,
93        int channelMask,
94        int frameCount,
95        audio_output_flags_t flags,
96        callback_t cbf,
97        void* user,
98        int notificationFrames,
99        int sessionId)
100    : mStatus(NO_INIT),
101      mIsTimed(false),
102      mPreviousPriority(ANDROID_PRIORITY_NORMAL),
103      mPreviousSchedulingGroup(ANDROID_TGROUP_DEFAULT)
104{
105    mStatus = set(streamType, sampleRate, format, channelMask,
106            frameCount, flags, cbf, user, notificationFrames,
107            0 /*sharedBuffer*/, false /*threadCanCallJava*/, sessionId);
108}
109
110// DEPRECATED
111AudioTrack::AudioTrack(
112        int streamType,
113        uint32_t sampleRate,
114        int format,
115        int channelMask,
116        int frameCount,
117        uint32_t flags,
118        callback_t cbf,
119        void* user,
120        int notificationFrames,
121        int sessionId)
122    : mStatus(NO_INIT),
123      mIsTimed(false),
124      mPreviousPriority(ANDROID_PRIORITY_NORMAL), mPreviousSchedulingGroup(ANDROID_TGROUP_DEFAULT)
125{
126    mStatus = set((audio_stream_type_t)streamType, sampleRate, (audio_format_t)format, channelMask,
127            frameCount, (audio_output_flags_t)flags, cbf, user, notificationFrames,
128            0 /*sharedBuffer*/, false /*threadCanCallJava*/, sessionId);
129}
130
131AudioTrack::AudioTrack(
132        audio_stream_type_t streamType,
133        uint32_t sampleRate,
134        audio_format_t format,
135        int channelMask,
136        const sp<IMemory>& sharedBuffer,
137        audio_output_flags_t flags,
138        callback_t cbf,
139        void* user,
140        int notificationFrames,
141        int sessionId)
142    : mStatus(NO_INIT),
143      mIsTimed(false),
144      mPreviousPriority(ANDROID_PRIORITY_NORMAL),
145      mPreviousSchedulingGroup(ANDROID_TGROUP_DEFAULT)
146{
147    mStatus = set(streamType, sampleRate, format, channelMask,
148            0 /*frameCount*/, flags, cbf, user, notificationFrames,
149            sharedBuffer, false /*threadCanCallJava*/, sessionId);
150}
151
152AudioTrack::~AudioTrack()
153{
154    ALOGV_IF(mSharedBuffer != 0, "Destructor sharedBuffer: %p", mSharedBuffer->pointer());
155
156    if (mStatus == NO_ERROR) {
157        // Make sure that callback function exits in the case where
158        // it is looping on buffer full condition in obtainBuffer().
159        // Otherwise the callback thread will never exit.
160        stop();
161        if (mAudioTrackThread != 0) {
162            mAudioTrackThread->requestExitAndWait();
163            mAudioTrackThread.clear();
164        }
165        mAudioTrack.clear();
166        IPCThreadState::self()->flushCommands();
167        AudioSystem::releaseAudioSessionId(mSessionId);
168    }
169}
170
171status_t AudioTrack::set(
172        audio_stream_type_t streamType,
173        uint32_t sampleRate,
174        audio_format_t format,
175        int channelMask,
176        int frameCount,
177        audio_output_flags_t flags,
178        callback_t cbf,
179        void* user,
180        int notificationFrames,
181        const sp<IMemory>& sharedBuffer,
182        bool threadCanCallJava,
183        int sessionId)
184{
185
186    ALOGV_IF(sharedBuffer != 0, "sharedBuffer: %p, size: %d", sharedBuffer->pointer(), sharedBuffer->size());
187
188    ALOGV("set() streamType %d frameCount %d flags %04x", streamType, frameCount, flags);
189
190    AutoMutex lock(mLock);
191    if (mAudioTrack != 0) {
192        ALOGE("Track already in use");
193        return INVALID_OPERATION;
194    }
195
196    // handle default values first.
197    if (streamType == AUDIO_STREAM_DEFAULT) {
198        streamType = AUDIO_STREAM_MUSIC;
199    }
200
201    int afSampleRate;
202    if (AudioSystem::getOutputSamplingRate(&afSampleRate, streamType) != NO_ERROR) {
203        return NO_INIT;
204    }
205    if (sampleRate == 0) {
206        sampleRate = afSampleRate;
207    }
208
209    // these below should probably come from the audioFlinger too...
210    if (format == AUDIO_FORMAT_DEFAULT) {
211        format = AUDIO_FORMAT_PCM_16_BIT;
212    }
213    if (channelMask == 0) {
214        channelMask = AUDIO_CHANNEL_OUT_STEREO;
215    }
216
217    // validate parameters
218    if (!audio_is_valid_format(format)) {
219        ALOGE("Invalid format");
220        return BAD_VALUE;
221    }
222
223    // force direct flag if format is not linear PCM
224    if (!audio_is_linear_pcm(format)) {
225        flags = (audio_output_flags_t)
226                ((flags | AUDIO_OUTPUT_FLAG_DIRECT) & ~AUDIO_OUTPUT_FLAG_FAST);
227    }
228
229    if (!audio_is_output_channel(channelMask)) {
230        ALOGE("Invalid channel mask");
231        return BAD_VALUE;
232    }
233    uint32_t channelCount = popcount(channelMask);
234
235    audio_io_handle_t output = AudioSystem::getOutput(
236                                    streamType,
237                                    sampleRate, format, channelMask,
238                                    flags);
239
240    if (output == 0) {
241        ALOGE("Could not get audio output for stream type %d", streamType);
242        return BAD_VALUE;
243    }
244
245    mVolume[LEFT] = 1.0f;
246    mVolume[RIGHT] = 1.0f;
247    mSendLevel = 0.0f;
248    mFrameCount = frameCount;
249    mNotificationFramesReq = notificationFrames;
250    mSessionId = sessionId;
251    mAuxEffectId = 0;
252    mCbf = cbf;
253
254    // create the IAudioTrack
255    status_t status = createTrack_l(streamType,
256                                  sampleRate,
257                                  format,
258                                  (uint32_t)channelMask,
259                                  frameCount,
260                                  flags,
261                                  sharedBuffer,
262                                  output);
263
264    if (status != NO_ERROR) {
265        return status;
266    }
267
268    if (cbf != NULL) {
269        mAudioTrackThread = new AudioTrackThread(*this, threadCanCallJava);
270    }
271
272    mStatus = NO_ERROR;
273
274    mStreamType = streamType;
275    mFormat = format;
276    mChannelMask = (uint32_t)channelMask;
277    mChannelCount = channelCount;
278    mSharedBuffer = sharedBuffer;
279    mMuted = false;
280    mActive = false;
281    mUserData = user;
282    mLoopCount = 0;
283    mMarkerPosition = 0;
284    mMarkerReached = false;
285    mNewPosition = 0;
286    mUpdatePeriod = 0;
287    mFlushed = false;
288    mFlags = flags;
289    AudioSystem::acquireAudioSessionId(mSessionId);
290    mRestoreStatus = NO_ERROR;
291    return NO_ERROR;
292}
293
294status_t AudioTrack::initCheck() const
295{
296    return mStatus;
297}
298
299// -------------------------------------------------------------------------
300
301uint32_t AudioTrack::latency() const
302{
303    return mLatency;
304}
305
306audio_stream_type_t AudioTrack::streamType() const
307{
308    return mStreamType;
309}
310
311audio_format_t AudioTrack::format() const
312{
313    return mFormat;
314}
315
316int AudioTrack::channelCount() const
317{
318    return mChannelCount;
319}
320
321uint32_t AudioTrack::frameCount() const
322{
323    return mCblk->frameCount;
324}
325
326size_t AudioTrack::frameSize() const
327{
328    if (audio_is_linear_pcm(mFormat)) {
329        return channelCount()*audio_bytes_per_sample(mFormat);
330    } else {
331        return sizeof(uint8_t);
332    }
333}
334
335sp<IMemory>& AudioTrack::sharedBuffer()
336{
337    return mSharedBuffer;
338}
339
340// -------------------------------------------------------------------------
341
342void AudioTrack::start()
343{
344    sp<AudioTrackThread> t = mAudioTrackThread;
345    status_t status = NO_ERROR;
346
347    ALOGV("start %p", this);
348    if (t != 0) {
349        if (t->exitPending()) {
350            if (t->requestExitAndWait() == WOULD_BLOCK) {
351                ALOGE("AudioTrack::start called from thread");
352                return;
353            }
354        }
355    }
356
357    AutoMutex lock(mLock);
358    // acquire a strong reference on the IMemory and IAudioTrack so that they cannot be destroyed
359    // while we are accessing the cblk
360    sp<IAudioTrack> audioTrack = mAudioTrack;
361    sp<IMemory> iMem = mCblkMemory;
362    audio_track_cblk_t* cblk = mCblk;
363
364    if (!mActive) {
365        mFlushed = false;
366        mActive = true;
367        mNewPosition = cblk->server + mUpdatePeriod;
368        cblk->lock.lock();
369        cblk->bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS;
370        cblk->waitTimeMs = 0;
371        android_atomic_and(~CBLK_DISABLED_ON, &cblk->flags);
372        pid_t tid;
373        if (t != 0) {
374            t->run("AudioTrack", ANDROID_PRIORITY_AUDIO);
375            tid = t->getTid();  // pid_t is unknown until run()
376            ALOGV("getTid=%d", tid);
377            if (tid == -1) {
378                tid = 0;
379            }
380        } else {
381            mPreviousPriority = getpriority(PRIO_PROCESS, 0);
382            mPreviousSchedulingGroup = androidGetThreadSchedulingGroup(0);
383            androidSetThreadPriority(0, ANDROID_PRIORITY_AUDIO);
384            tid = 0;    // not gettid()
385        }
386
387        ALOGV("start %p before lock cblk %p", this, mCblk);
388        if (!(cblk->flags & CBLK_INVALID_MSK)) {
389            cblk->lock.unlock();
390            ALOGV("mAudioTrack->start(tid=%d)", tid);
391            status = mAudioTrack->start(tid);
392            cblk->lock.lock();
393            if (status == DEAD_OBJECT) {
394                android_atomic_or(CBLK_INVALID_ON, &cblk->flags);
395            }
396        }
397        if (cblk->flags & CBLK_INVALID_MSK) {
398            status = restoreTrack_l(cblk, true);
399        }
400        cblk->lock.unlock();
401        if (status != NO_ERROR) {
402            ALOGV("start() failed");
403            mActive = false;
404            if (t != 0) {
405                t->requestExit();
406            } else {
407                setpriority(PRIO_PROCESS, 0, mPreviousPriority);
408                androidSetThreadSchedulingGroup(0, mPreviousSchedulingGroup);
409            }
410        }
411    }
412
413}
414
415void AudioTrack::stop()
416{
417    sp<AudioTrackThread> t = mAudioTrackThread;
418
419    ALOGV("stop %p", this);
420
421    AutoMutex lock(mLock);
422    if (mActive) {
423        mActive = false;
424        mCblk->cv.signal();
425        mAudioTrack->stop();
426        // Cancel loops (If we are in the middle of a loop, playback
427        // would not stop until loopCount reaches 0).
428        setLoop_l(0, 0, 0);
429        // the playback head position will reset to 0, so if a marker is set, we need
430        // to activate it again
431        mMarkerReached = false;
432        // Force flush if a shared buffer is used otherwise audioflinger
433        // will not stop before end of buffer is reached.
434        if (mSharedBuffer != 0) {
435            flush_l();
436        }
437        if (t != 0) {
438            t->requestExit();
439        } else {
440            setpriority(PRIO_PROCESS, 0, mPreviousPriority);
441            androidSetThreadSchedulingGroup(0, mPreviousSchedulingGroup);
442        }
443    }
444
445}
446
447bool AudioTrack::stopped() const
448{
449    AutoMutex lock(mLock);
450    return stopped_l();
451}
452
453void AudioTrack::flush()
454{
455    AutoMutex lock(mLock);
456    flush_l();
457}
458
459// must be called with mLock held
460void AudioTrack::flush_l()
461{
462    ALOGV("flush");
463
464    // clear playback marker and periodic update counter
465    mMarkerPosition = 0;
466    mMarkerReached = false;
467    mUpdatePeriod = 0;
468
469    if (!mActive) {
470        mFlushed = true;
471        mAudioTrack->flush();
472        // Release AudioTrack callback thread in case it was waiting for new buffers
473        // in AudioTrack::obtainBuffer()
474        mCblk->cv.signal();
475    }
476}
477
478void AudioTrack::pause()
479{
480    ALOGV("pause");
481    AutoMutex lock(mLock);
482    if (mActive) {
483        mActive = false;
484        mAudioTrack->pause();
485    }
486}
487
488void AudioTrack::mute(bool e)
489{
490    mAudioTrack->mute(e);
491    mMuted = e;
492}
493
494bool AudioTrack::muted() const
495{
496    return mMuted;
497}
498
499status_t AudioTrack::setVolume(float left, float right)
500{
501    if (left < 0.0f || left > 1.0f || right < 0.0f || right > 1.0f) {
502        return BAD_VALUE;
503    }
504
505    AutoMutex lock(mLock);
506    mVolume[LEFT] = left;
507    mVolume[RIGHT] = right;
508
509    mCblk->setVolumeLR((uint32_t(uint16_t(right * 0x1000)) << 16) | uint16_t(left * 0x1000));
510
511    return NO_ERROR;
512}
513
514void AudioTrack::getVolume(float* left, float* right) const
515{
516    if (left != NULL) {
517        *left  = mVolume[LEFT];
518    }
519    if (right != NULL) {
520        *right = mVolume[RIGHT];
521    }
522}
523
524status_t AudioTrack::setAuxEffectSendLevel(float level)
525{
526    ALOGV("setAuxEffectSendLevel(%f)", level);
527    if (level < 0.0f || level > 1.0f) {
528        return BAD_VALUE;
529    }
530    AutoMutex lock(mLock);
531
532    mSendLevel = level;
533
534    mCblk->setSendLevel(level);
535
536    return NO_ERROR;
537}
538
539void AudioTrack::getAuxEffectSendLevel(float* level) const
540{
541    if (level != NULL) {
542        *level  = mSendLevel;
543    }
544}
545
546status_t AudioTrack::setSampleRate(int rate)
547{
548    int afSamplingRate;
549
550    if (mIsTimed) {
551        return INVALID_OPERATION;
552    }
553
554    if (AudioSystem::getOutputSamplingRate(&afSamplingRate, mStreamType) != NO_ERROR) {
555        return NO_INIT;
556    }
557    // Resampler implementation limits input sampling rate to 2 x output sampling rate.
558    if (rate <= 0 || rate > afSamplingRate*2 ) return BAD_VALUE;
559
560    AutoMutex lock(mLock);
561    mCblk->sampleRate = rate;
562    return NO_ERROR;
563}
564
565uint32_t AudioTrack::getSampleRate() const
566{
567    if (mIsTimed) {
568        return INVALID_OPERATION;
569    }
570
571    AutoMutex lock(mLock);
572    return mCblk->sampleRate;
573}
574
575status_t AudioTrack::setLoop(uint32_t loopStart, uint32_t loopEnd, int loopCount)
576{
577    AutoMutex lock(mLock);
578    return setLoop_l(loopStart, loopEnd, loopCount);
579}
580
581// must be called with mLock held
582status_t AudioTrack::setLoop_l(uint32_t loopStart, uint32_t loopEnd, int loopCount)
583{
584    audio_track_cblk_t* cblk = mCblk;
585
586    Mutex::Autolock _l(cblk->lock);
587
588    if (loopCount == 0) {
589        cblk->loopStart = UINT_MAX;
590        cblk->loopEnd = UINT_MAX;
591        cblk->loopCount = 0;
592        mLoopCount = 0;
593        return NO_ERROR;
594    }
595
596    if (mIsTimed) {
597        return INVALID_OPERATION;
598    }
599
600    if (loopStart >= loopEnd ||
601        loopEnd - loopStart > cblk->frameCount ||
602        cblk->server > loopStart) {
603        ALOGE("setLoop invalid value: loopStart %d, loopEnd %d, loopCount %d, framecount %d, user %d", loopStart, loopEnd, loopCount, cblk->frameCount, cblk->user);
604        return BAD_VALUE;
605    }
606
607    if ((mSharedBuffer != 0) && (loopEnd > cblk->frameCount)) {
608        ALOGE("setLoop invalid value: loop markers beyond data: loopStart %d, loopEnd %d, framecount %d",
609            loopStart, loopEnd, cblk->frameCount);
610        return BAD_VALUE;
611    }
612
613    cblk->loopStart = loopStart;
614    cblk->loopEnd = loopEnd;
615    cblk->loopCount = loopCount;
616    mLoopCount = loopCount;
617
618    return NO_ERROR;
619}
620
621status_t AudioTrack::setMarkerPosition(uint32_t marker)
622{
623    if (mCbf == NULL) return INVALID_OPERATION;
624
625    mMarkerPosition = marker;
626    mMarkerReached = false;
627
628    return NO_ERROR;
629}
630
631status_t AudioTrack::getMarkerPosition(uint32_t *marker) const
632{
633    if (marker == NULL) return BAD_VALUE;
634
635    *marker = mMarkerPosition;
636
637    return NO_ERROR;
638}
639
640status_t AudioTrack::setPositionUpdatePeriod(uint32_t updatePeriod)
641{
642    if (mCbf == NULL) return INVALID_OPERATION;
643
644    uint32_t curPosition;
645    getPosition(&curPosition);
646    mNewPosition = curPosition + updatePeriod;
647    mUpdatePeriod = updatePeriod;
648
649    return NO_ERROR;
650}
651
652status_t AudioTrack::getPositionUpdatePeriod(uint32_t *updatePeriod) const
653{
654    if (updatePeriod == NULL) return BAD_VALUE;
655
656    *updatePeriod = mUpdatePeriod;
657
658    return NO_ERROR;
659}
660
661status_t AudioTrack::setPosition(uint32_t position)
662{
663    if (mIsTimed) return INVALID_OPERATION;
664
665    AutoMutex lock(mLock);
666
667    if (!stopped_l()) return INVALID_OPERATION;
668
669    Mutex::Autolock _l(mCblk->lock);
670
671    if (position > mCblk->user) return BAD_VALUE;
672
673    mCblk->server = position;
674    android_atomic_or(CBLK_FORCEREADY_ON, &mCblk->flags);
675
676    return NO_ERROR;
677}
678
679status_t AudioTrack::getPosition(uint32_t *position)
680{
681    if (position == NULL) return BAD_VALUE;
682    AutoMutex lock(mLock);
683    *position = mFlushed ? 0 : mCblk->server;
684
685    return NO_ERROR;
686}
687
688status_t AudioTrack::reload()
689{
690    AutoMutex lock(mLock);
691
692    if (!stopped_l()) return INVALID_OPERATION;
693
694    flush_l();
695
696    mCblk->stepUser(mCblk->frameCount);
697
698    return NO_ERROR;
699}
700
701audio_io_handle_t AudioTrack::getOutput()
702{
703    AutoMutex lock(mLock);
704    return getOutput_l();
705}
706
707// must be called with mLock held
708audio_io_handle_t AudioTrack::getOutput_l()
709{
710    return AudioSystem::getOutput(mStreamType,
711            mCblk->sampleRate, mFormat, mChannelMask, mFlags);
712}
713
714int AudioTrack::getSessionId() const
715{
716    return mSessionId;
717}
718
719status_t AudioTrack::attachAuxEffect(int effectId)
720{
721    ALOGV("attachAuxEffect(%d)", effectId);
722    status_t status = mAudioTrack->attachAuxEffect(effectId);
723    if (status == NO_ERROR) {
724        mAuxEffectId = effectId;
725    }
726    return status;
727}
728
729// -------------------------------------------------------------------------
730
731// must be called with mLock held
732status_t AudioTrack::createTrack_l(
733        audio_stream_type_t streamType,
734        uint32_t sampleRate,
735        audio_format_t format,
736        uint32_t channelMask,
737        int frameCount,
738        audio_output_flags_t flags,
739        const sp<IMemory>& sharedBuffer,
740        audio_io_handle_t output)
741{
742    status_t status;
743    const sp<IAudioFlinger>& audioFlinger = AudioSystem::get_audio_flinger();
744    if (audioFlinger == 0) {
745        ALOGE("Could not get audioflinger");
746        return NO_INIT;
747    }
748
749    int afSampleRate;
750    if (AudioSystem::getSamplingRate(output, streamType, &afSampleRate) != NO_ERROR) {
751        return NO_INIT;
752    }
753    int afFrameCount;
754    if (AudioSystem::getFrameCount(output, streamType, &afFrameCount) != NO_ERROR) {
755        return NO_INIT;
756    }
757    uint32_t afLatency;
758    if (AudioSystem::getLatency(output, streamType, &afLatency) != NO_ERROR) {
759        return NO_INIT;
760    }
761
762    // Client decides whether the track is TIMED (see below), but can only express a preference
763    // for FAST.  Server will perform additional tests.
764    if ((flags & AUDIO_OUTPUT_FLAG_FAST) && !(
765            // either of these use cases:
766            // use case 1: shared buffer
767            (sharedBuffer != 0) ||
768            // use case 2: callback handler
769            (mCbf != NULL))) {
770        ALOGW("AUDIO_OUTPUT_FLAG_FAST denied");
771        flags = (audio_output_flags_t) (flags & ~AUDIO_OUTPUT_FLAG_FAST);
772    }
773    ALOGV("createTrack_l() output %d afFrameCount %d afLatency %d", output, afFrameCount, afLatency);
774
775    mNotificationFramesAct = mNotificationFramesReq;
776    if (!audio_is_linear_pcm(format)) {
777        if (sharedBuffer != 0) {
778            frameCount = sharedBuffer->size();
779        }
780    } else {
781        // Ensure that buffer depth covers at least audio hardware latency
782        uint32_t minBufCount = afLatency / ((1000 * afFrameCount)/afSampleRate);
783        if (minBufCount < 2) minBufCount = 2;
784
785        int minFrameCount = (afFrameCount*sampleRate*minBufCount)/afSampleRate;
786
787        if (sharedBuffer == 0) {
788            if (frameCount == 0) {
789                frameCount = minFrameCount;
790            }
791            if (mNotificationFramesAct == 0) {
792                mNotificationFramesAct = frameCount/2;
793            }
794            // Make sure that application is notified with sufficient margin
795            // before underrun
796            if (mNotificationFramesAct > (uint32_t)frameCount/2) {
797                mNotificationFramesAct = frameCount/2;
798            }
799            if (frameCount < minFrameCount && !(flags & AUDIO_OUTPUT_FLAG_FAST)) {
800                // not ALOGW because it happens all the time when playing key clicks over A2DP
801                ALOGV("Minimum buffer size corrected from %d to %d",
802                         frameCount, minFrameCount);
803                frameCount = minFrameCount;
804            }
805        } else {
806            // Ensure that buffer alignment matches channelCount
807            int channelCount = popcount(channelMask);
808            if (((uint32_t)sharedBuffer->pointer() & (channelCount | 1)) != 0) {
809                ALOGE("Invalid buffer alignement: address %p, channelCount %d", sharedBuffer->pointer(), channelCount);
810                return BAD_VALUE;
811            }
812            frameCount = sharedBuffer->size()/channelCount/sizeof(int16_t);
813        }
814    }
815
816    IAudioFlinger::track_flags_t trackFlags = IAudioFlinger::TRACK_DEFAULT;
817    if (mIsTimed) {
818        trackFlags |= IAudioFlinger::TRACK_TIMED;
819    }
820    if (flags & AUDIO_OUTPUT_FLAG_FAST) {
821        trackFlags |= IAudioFlinger::TRACK_FAST;
822    }
823
824    sp<IAudioTrack> track = audioFlinger->createTrack(getpid(),
825                                                      streamType,
826                                                      sampleRate,
827                                                      format,
828                                                      channelMask,
829                                                      frameCount,
830                                                      trackFlags,
831                                                      sharedBuffer,
832                                                      output,
833                                                      &mSessionId,
834                                                      &status);
835
836    if (track == 0) {
837        ALOGE("AudioFlinger could not create track, status: %d", status);
838        return status;
839    }
840    sp<IMemory> cblk = track->getCblk();
841    if (cblk == 0) {
842        ALOGE("Could not get control block");
843        return NO_INIT;
844    }
845    mAudioTrack = track;
846    mCblkMemory = cblk;
847    mCblk = static_cast<audio_track_cblk_t*>(cblk->pointer());
848    android_atomic_or(CBLK_DIRECTION_OUT, &mCblk->flags);
849    if (sharedBuffer == 0) {
850        mCblk->buffers = (char*)mCblk + sizeof(audio_track_cblk_t);
851    } else {
852        mCblk->buffers = sharedBuffer->pointer();
853        // Force buffer full condition as data is already present in shared memory
854        mCblk->stepUser(mCblk->frameCount);
855    }
856
857    mCblk->setVolumeLR((uint32_t(uint16_t(mVolume[RIGHT] * 0x1000)) << 16) | uint16_t(mVolume[LEFT] * 0x1000));
858    mCblk->setSendLevel(mSendLevel);
859    mAudioTrack->attachAuxEffect(mAuxEffectId);
860    mCblk->bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS;
861    mCblk->waitTimeMs = 0;
862    mRemainingFrames = mNotificationFramesAct;
863    mLatency = afLatency + (1000*mCblk->frameCount) / sampleRate;
864    return NO_ERROR;
865}
866
867status_t AudioTrack::obtainBuffer(Buffer* audioBuffer, int32_t waitCount)
868{
869    AutoMutex lock(mLock);
870    bool active;
871    status_t result = NO_ERROR;
872    audio_track_cblk_t* cblk = mCblk;
873    uint32_t framesReq = audioBuffer->frameCount;
874    uint32_t waitTimeMs = (waitCount < 0) ? cblk->bufferTimeoutMs : WAIT_PERIOD_MS;
875
876    audioBuffer->frameCount  = 0;
877    audioBuffer->size = 0;
878
879    uint32_t framesAvail = cblk->framesAvailable();
880
881    cblk->lock.lock();
882    if (cblk->flags & CBLK_INVALID_MSK) {
883        goto create_new_track;
884    }
885    cblk->lock.unlock();
886
887    if (framesAvail == 0) {
888        cblk->lock.lock();
889        goto start_loop_here;
890        while (framesAvail == 0) {
891            active = mActive;
892            if (CC_UNLIKELY(!active)) {
893                ALOGV("Not active and NO_MORE_BUFFERS");
894                cblk->lock.unlock();
895                return NO_MORE_BUFFERS;
896            }
897            if (CC_UNLIKELY(!waitCount)) {
898                cblk->lock.unlock();
899                return WOULD_BLOCK;
900            }
901            if (!(cblk->flags & CBLK_INVALID_MSK)) {
902                mLock.unlock();
903                result = cblk->cv.waitRelative(cblk->lock, milliseconds(waitTimeMs));
904                cblk->lock.unlock();
905                mLock.lock();
906                if (!mActive) {
907                    return status_t(STOPPED);
908                }
909                cblk->lock.lock();
910            }
911
912            if (cblk->flags & CBLK_INVALID_MSK) {
913                goto create_new_track;
914            }
915            if (CC_UNLIKELY(result != NO_ERROR)) {
916                cblk->waitTimeMs += waitTimeMs;
917                if (cblk->waitTimeMs >= cblk->bufferTimeoutMs) {
918                    // timing out when a loop has been set and we have already written upto loop end
919                    // is a normal condition: no need to wake AudioFlinger up.
920                    if (cblk->user < cblk->loopEnd) {
921                        ALOGW(   "obtainBuffer timed out (is the CPU pegged?) %p "
922                                "user=%08x, server=%08x", this, cblk->user, cblk->server);
923                        //unlock cblk mutex before calling mAudioTrack->start() (see issue #1617140)
924                        cblk->lock.unlock();
925                        result = mAudioTrack->start(0); // callback thread hasn't changed
926                        cblk->lock.lock();
927                        if (result == DEAD_OBJECT) {
928                            android_atomic_or(CBLK_INVALID_ON, &cblk->flags);
929create_new_track:
930                            result = restoreTrack_l(cblk, false);
931                        }
932                        if (result != NO_ERROR) {
933                            ALOGW("obtainBuffer create Track error %d", result);
934                            cblk->lock.unlock();
935                            return result;
936                        }
937                    }
938                    cblk->waitTimeMs = 0;
939                }
940
941                if (--waitCount == 0) {
942                    cblk->lock.unlock();
943                    return TIMED_OUT;
944                }
945            }
946            // read the server count again
947        start_loop_here:
948            framesAvail = cblk->framesAvailable_l();
949        }
950        cblk->lock.unlock();
951    }
952
953    // restart track if it was disabled by audioflinger due to previous underrun
954    if (mActive && (cblk->flags & CBLK_DISABLED_MSK)) {
955        android_atomic_and(~CBLK_DISABLED_ON, &cblk->flags);
956        ALOGW("obtainBuffer() track %p disabled, restarting", this);
957        mAudioTrack->start(0);  // callback thread hasn't changed
958    }
959
960    cblk->waitTimeMs = 0;
961
962    if (framesReq > framesAvail) {
963        framesReq = framesAvail;
964    }
965
966    uint32_t u = cblk->user;
967    uint32_t bufferEnd = cblk->userBase + cblk->frameCount;
968
969    if (framesReq > bufferEnd - u) {
970        framesReq = bufferEnd - u;
971    }
972
973    audioBuffer->flags = mMuted ? Buffer::MUTE : 0;
974    audioBuffer->channelCount = mChannelCount;
975    audioBuffer->frameCount = framesReq;
976    audioBuffer->size = framesReq * cblk->frameSize;
977    if (audio_is_linear_pcm(mFormat)) {
978        audioBuffer->format = AUDIO_FORMAT_PCM_16_BIT;
979    } else {
980        audioBuffer->format = mFormat;
981    }
982    audioBuffer->raw = (int8_t *)cblk->buffer(u);
983    active = mActive;
984    return active ? status_t(NO_ERROR) : status_t(STOPPED);
985}
986
987void AudioTrack::releaseBuffer(Buffer* audioBuffer)
988{
989    AutoMutex lock(mLock);
990    mCblk->stepUser(audioBuffer->frameCount);
991}
992
993// -------------------------------------------------------------------------
994
995ssize_t AudioTrack::write(const void* buffer, size_t userSize)
996{
997
998    if (mSharedBuffer != 0) return INVALID_OPERATION;
999    if (mIsTimed) return INVALID_OPERATION;
1000
1001    if (ssize_t(userSize) < 0) {
1002        // Sanity-check: user is most-likely passing an error code, and it would
1003        // make the return value ambiguous (actualSize vs error).
1004        ALOGE("AudioTrack::write(buffer=%p, size=%u (%d)",
1005                buffer, userSize, userSize);
1006        return BAD_VALUE;
1007    }
1008
1009    ALOGV("write %p: %d bytes, mActive=%d", this, userSize, mActive);
1010
1011    // acquire a strong reference on the IMemory and IAudioTrack so that they cannot be destroyed
1012    // while we are accessing the cblk
1013    mLock.lock();
1014    sp<IAudioTrack> audioTrack = mAudioTrack;
1015    sp<IMemory> iMem = mCblkMemory;
1016    mLock.unlock();
1017
1018    ssize_t written = 0;
1019    const int8_t *src = (const int8_t *)buffer;
1020    Buffer audioBuffer;
1021    size_t frameSz = frameSize();
1022
1023    do {
1024        audioBuffer.frameCount = userSize/frameSz;
1025
1026        status_t err = obtainBuffer(&audioBuffer, -1);
1027        if (err < 0) {
1028            // out of buffers, return #bytes written
1029            if (err == status_t(NO_MORE_BUFFERS))
1030                break;
1031            return ssize_t(err);
1032        }
1033
1034        size_t toWrite;
1035
1036        if (mFormat == AUDIO_FORMAT_PCM_8_BIT && !(mFlags & AUDIO_OUTPUT_FLAG_DIRECT)) {
1037            // Divide capacity by 2 to take expansion into account
1038            toWrite = audioBuffer.size>>1;
1039            memcpy_to_i16_from_u8(audioBuffer.i16, (const uint8_t *) src, toWrite);
1040        } else {
1041            toWrite = audioBuffer.size;
1042            memcpy(audioBuffer.i8, src, toWrite);
1043            src += toWrite;
1044        }
1045        userSize -= toWrite;
1046        written += toWrite;
1047
1048        releaseBuffer(&audioBuffer);
1049    } while (userSize >= frameSz);
1050
1051    return written;
1052}
1053
1054// -------------------------------------------------------------------------
1055
1056TimedAudioTrack::TimedAudioTrack() {
1057    mIsTimed = true;
1058}
1059
1060status_t TimedAudioTrack::allocateTimedBuffer(size_t size, sp<IMemory>* buffer)
1061{
1062    status_t result = UNKNOWN_ERROR;
1063
1064    // If the track is not invalid already, try to allocate a buffer.  alloc
1065    // fails indicating that the server is dead, flag the track as invalid so
1066    // we can attempt to restore in in just a bit.
1067    if (!(mCblk->flags & CBLK_INVALID_MSK)) {
1068        result = mAudioTrack->allocateTimedBuffer(size, buffer);
1069        if (result == DEAD_OBJECT) {
1070            android_atomic_or(CBLK_INVALID_ON, &mCblk->flags);
1071        }
1072    }
1073
1074    // If the track is invalid at this point, attempt to restore it. and try the
1075    // allocation one more time.
1076    if (mCblk->flags & CBLK_INVALID_MSK) {
1077        mCblk->lock.lock();
1078        result = restoreTrack_l(mCblk, false);
1079        mCblk->lock.unlock();
1080
1081        if (result == OK)
1082            result = mAudioTrack->allocateTimedBuffer(size, buffer);
1083    }
1084
1085    return result;
1086}
1087
1088status_t TimedAudioTrack::queueTimedBuffer(const sp<IMemory>& buffer,
1089                                           int64_t pts)
1090{
1091    // restart track if it was disabled by audioflinger due to previous underrun
1092    if (mActive && (mCblk->flags & CBLK_DISABLED_MSK)) {
1093        android_atomic_and(~CBLK_DISABLED_ON, &mCblk->flags);
1094        ALOGW("queueTimedBuffer() track %p disabled, restarting", this);
1095        mAudioTrack->start(0);
1096    }
1097
1098    return mAudioTrack->queueTimedBuffer(buffer, pts);
1099}
1100
1101status_t TimedAudioTrack::setMediaTimeTransform(const LinearTransform& xform,
1102                                                TargetTimeline target)
1103{
1104    return mAudioTrack->setMediaTimeTransform(xform, target);
1105}
1106
1107// -------------------------------------------------------------------------
1108
1109bool AudioTrack::processAudioBuffer(const sp<AudioTrackThread>& thread)
1110{
1111    Buffer audioBuffer;
1112    uint32_t frames;
1113    size_t writtenSize;
1114
1115    mLock.lock();
1116    // acquire a strong reference on the IMemory and IAudioTrack so that they cannot be destroyed
1117    // while we are accessing the cblk
1118    sp<IAudioTrack> audioTrack = mAudioTrack;
1119    sp<IMemory> iMem = mCblkMemory;
1120    audio_track_cblk_t* cblk = mCblk;
1121    bool active = mActive;
1122    mLock.unlock();
1123
1124    // Manage underrun callback
1125    if (active && (cblk->framesAvailable() == cblk->frameCount)) {
1126        ALOGV("Underrun user: %x, server: %x, flags %04x", cblk->user, cblk->server, cblk->flags);
1127        if (!(android_atomic_or(CBLK_UNDERRUN_ON, &cblk->flags) & CBLK_UNDERRUN_MSK)) {
1128            mCbf(EVENT_UNDERRUN, mUserData, 0);
1129            if (cblk->server == cblk->frameCount) {
1130                mCbf(EVENT_BUFFER_END, mUserData, 0);
1131            }
1132            if (mSharedBuffer != 0) return false;
1133        }
1134    }
1135
1136    // Manage loop end callback
1137    while (mLoopCount > cblk->loopCount) {
1138        int loopCount = -1;
1139        mLoopCount--;
1140        if (mLoopCount >= 0) loopCount = mLoopCount;
1141
1142        mCbf(EVENT_LOOP_END, mUserData, (void *)&loopCount);
1143    }
1144
1145    // Manage marker callback
1146    if (!mMarkerReached && (mMarkerPosition > 0)) {
1147        if (cblk->server >= mMarkerPosition) {
1148            mCbf(EVENT_MARKER, mUserData, (void *)&mMarkerPosition);
1149            mMarkerReached = true;
1150        }
1151    }
1152
1153    // Manage new position callback
1154    if (mUpdatePeriod > 0) {
1155        while (cblk->server >= mNewPosition) {
1156            mCbf(EVENT_NEW_POS, mUserData, (void *)&mNewPosition);
1157            mNewPosition += mUpdatePeriod;
1158        }
1159    }
1160
1161    // If Shared buffer is used, no data is requested from client.
1162    if (mSharedBuffer != 0) {
1163        frames = 0;
1164    } else {
1165        frames = mRemainingFrames;
1166    }
1167
1168    // See description of waitCount parameter at declaration of obtainBuffer().
1169    // The logic below prevents us from being stuck below at obtainBuffer()
1170    // not being able to handle timed events (position, markers, loops).
1171    int32_t waitCount = -1;
1172    if (mUpdatePeriod || (!mMarkerReached && mMarkerPosition) || mLoopCount) {
1173        waitCount = 1;
1174    }
1175
1176    do {
1177
1178        audioBuffer.frameCount = frames;
1179
1180        status_t err = obtainBuffer(&audioBuffer, waitCount);
1181        if (err < NO_ERROR) {
1182            if (err != TIMED_OUT) {
1183                ALOGE_IF(err != status_t(NO_MORE_BUFFERS), "Error obtaining an audio buffer, giving up.");
1184                return false;
1185            }
1186            break;
1187        }
1188        if (err == status_t(STOPPED)) return false;
1189
1190        // Divide buffer size by 2 to take into account the expansion
1191        // due to 8 to 16 bit conversion: the callback must fill only half
1192        // of the destination buffer
1193        if (mFormat == AUDIO_FORMAT_PCM_8_BIT && !(mFlags & AUDIO_OUTPUT_FLAG_DIRECT)) {
1194            audioBuffer.size >>= 1;
1195        }
1196
1197        size_t reqSize = audioBuffer.size;
1198        mCbf(EVENT_MORE_DATA, mUserData, &audioBuffer);
1199        writtenSize = audioBuffer.size;
1200
1201        // Sanity check on returned size
1202        if (ssize_t(writtenSize) <= 0) {
1203            // The callback is done filling buffers
1204            // Keep this thread going to handle timed events and
1205            // still try to get more data in intervals of WAIT_PERIOD_MS
1206            // but don't just loop and block the CPU, so wait
1207            usleep(WAIT_PERIOD_MS*1000);
1208            break;
1209        }
1210        if (writtenSize > reqSize) writtenSize = reqSize;
1211
1212        if (mFormat == AUDIO_FORMAT_PCM_8_BIT && !(mFlags & AUDIO_OUTPUT_FLAG_DIRECT)) {
1213            // 8 to 16 bit conversion, note that source and destination are the same address
1214            memcpy_to_i16_from_u8(audioBuffer.i16, (const uint8_t *) audioBuffer.i8, writtenSize);
1215            writtenSize <<= 1;
1216        }
1217
1218        audioBuffer.size = writtenSize;
1219        // NOTE: mCblk->frameSize is not equal to AudioTrack::frameSize() for
1220        // 8 bit PCM data: in this case,  mCblk->frameSize is based on a sample size of
1221        // 16 bit.
1222        audioBuffer.frameCount = writtenSize/mCblk->frameSize;
1223
1224        frames -= audioBuffer.frameCount;
1225
1226        releaseBuffer(&audioBuffer);
1227    }
1228    while (frames);
1229
1230    if (frames == 0) {
1231        mRemainingFrames = mNotificationFramesAct;
1232    } else {
1233        mRemainingFrames = frames;
1234    }
1235    return true;
1236}
1237
1238// must be called with mLock and cblk.lock held. Callers must also hold strong references on
1239// the IAudioTrack and IMemory in case they are recreated here.
1240// If the IAudioTrack is successfully restored, the cblk pointer is updated
1241status_t AudioTrack::restoreTrack_l(audio_track_cblk_t*& cblk, bool fromStart)
1242{
1243    status_t result;
1244
1245    if (!(android_atomic_or(CBLK_RESTORING_ON, &cblk->flags) & CBLK_RESTORING_MSK)) {
1246        ALOGW("dead IAudioTrack, creating a new one from %s TID %d",
1247            fromStart ? "start()" : "obtainBuffer()", gettid());
1248
1249        // signal old cblk condition so that other threads waiting for available buffers stop
1250        // waiting now
1251        cblk->cv.broadcast();
1252        cblk->lock.unlock();
1253
1254        // refresh the audio configuration cache in this process to make sure we get new
1255        // output parameters in getOutput_l() and createTrack_l()
1256        AudioSystem::clearAudioConfigCache();
1257
1258        // if the new IAudioTrack is created, createTrack_l() will modify the
1259        // following member variables: mAudioTrack, mCblkMemory and mCblk.
1260        // It will also delete the strong references on previous IAudioTrack and IMemory
1261        result = createTrack_l(mStreamType,
1262                               cblk->sampleRate,
1263                               mFormat,
1264                               mChannelMask,
1265                               mFrameCount,
1266                               mFlags,
1267                               mSharedBuffer,
1268                               getOutput_l());
1269
1270        if (result == NO_ERROR) {
1271            uint32_t user = cblk->user;
1272            uint32_t server = cblk->server;
1273            // restore write index and set other indexes to reflect empty buffer status
1274            mCblk->user = user;
1275            mCblk->server = user;
1276            mCblk->userBase = user;
1277            mCblk->serverBase = user;
1278            // restore loop: this is not guaranteed to succeed if new frame count is not
1279            // compatible with loop length
1280            setLoop_l(cblk->loopStart, cblk->loopEnd, cblk->loopCount);
1281            if (!fromStart) {
1282                mCblk->bufferTimeoutMs = MAX_RUN_TIMEOUT_MS;
1283                // Make sure that a client relying on callback events indicating underrun or
1284                // the actual amount of audio frames played (e.g SoundPool) receives them.
1285                if (mSharedBuffer == 0) {
1286                    uint32_t frames = 0;
1287                    if (user > server) {
1288                        frames = ((user - server) > mCblk->frameCount) ?
1289                                mCblk->frameCount : (user - server);
1290                        memset(mCblk->buffers, 0, frames * mCblk->frameSize);
1291                    }
1292                    // restart playback even if buffer is not completely filled.
1293                    android_atomic_or(CBLK_FORCEREADY_ON, &mCblk->flags);
1294                    // stepUser() clears CBLK_UNDERRUN_ON flag enabling underrun callbacks to
1295                    // the client
1296                    mCblk->stepUser(frames);
1297                }
1298            }
1299            if (mActive) {
1300                result = mAudioTrack->start(0); // callback thread hasn't changed
1301                ALOGW_IF(result != NO_ERROR, "restoreTrack_l() start() failed status %d", result);
1302            }
1303            if (fromStart && result == NO_ERROR) {
1304                mNewPosition = mCblk->server + mUpdatePeriod;
1305            }
1306        }
1307        if (result != NO_ERROR) {
1308            android_atomic_and(~CBLK_RESTORING_ON, &cblk->flags);
1309            ALOGW_IF(result != NO_ERROR, "restoreTrack_l() failed status %d", result);
1310        }
1311        mRestoreStatus = result;
1312        // signal old cblk condition for other threads waiting for restore completion
1313        android_atomic_or(CBLK_RESTORED_ON, &cblk->flags);
1314        cblk->cv.broadcast();
1315    } else {
1316        if (!(cblk->flags & CBLK_RESTORED_MSK)) {
1317            ALOGW("dead IAudioTrack, waiting for a new one TID %d", gettid());
1318            mLock.unlock();
1319            result = cblk->cv.waitRelative(cblk->lock, milliseconds(RESTORE_TIMEOUT_MS));
1320            if (result == NO_ERROR) {
1321                result = mRestoreStatus;
1322            }
1323            cblk->lock.unlock();
1324            mLock.lock();
1325        } else {
1326            ALOGW("dead IAudioTrack, already restored TID %d", gettid());
1327            result = mRestoreStatus;
1328            cblk->lock.unlock();
1329        }
1330    }
1331    ALOGV("restoreTrack_l() status %d mActive %d cblk %p, old cblk %p flags %08x old flags %08x",
1332        result, mActive, mCblk, cblk, mCblk->flags, cblk->flags);
1333
1334    if (result == NO_ERROR) {
1335        // from now on we switch to the newly created cblk
1336        cblk = mCblk;
1337    }
1338    cblk->lock.lock();
1339
1340    ALOGW_IF(result != NO_ERROR, "restoreTrack_l() error %d TID %d", result, gettid());
1341
1342    return result;
1343}
1344
1345status_t AudioTrack::dump(int fd, const Vector<String16>& args) const
1346{
1347
1348    const size_t SIZE = 256;
1349    char buffer[SIZE];
1350    String8 result;
1351
1352    result.append(" AudioTrack::dump\n");
1353    snprintf(buffer, 255, "  stream type(%d), left - right volume(%f, %f)\n", mStreamType, mVolume[0], mVolume[1]);
1354    result.append(buffer);
1355    snprintf(buffer, 255, "  format(%d), channel count(%d), frame count(%d)\n", mFormat, mChannelCount, mCblk->frameCount);
1356    result.append(buffer);
1357    snprintf(buffer, 255, "  sample rate(%d), status(%d), muted(%d)\n", (mCblk == 0) ? 0 : mCblk->sampleRate, mStatus, mMuted);
1358    result.append(buffer);
1359    snprintf(buffer, 255, "  active(%d), latency (%d)\n", mActive, mLatency);
1360    result.append(buffer);
1361    ::write(fd, result.string(), result.size());
1362    return NO_ERROR;
1363}
1364
1365// =========================================================================
1366
1367AudioTrack::AudioTrackThread::AudioTrackThread(AudioTrack& receiver, bool bCanCallJava)
1368    : Thread(bCanCallJava), mReceiver(receiver)
1369{
1370}
1371
1372bool AudioTrack::AudioTrackThread::threadLoop()
1373{
1374    return mReceiver.processAudioBuffer(this);
1375}
1376
1377status_t AudioTrack::AudioTrackThread::readyToRun()
1378{
1379    return NO_ERROR;
1380}
1381
1382void AudioTrack::AudioTrackThread::onFirstRef()
1383{
1384}
1385
1386// =========================================================================
1387
1388
1389audio_track_cblk_t::audio_track_cblk_t()
1390    : lock(Mutex::SHARED), cv(Condition::SHARED), user(0), server(0),
1391    userBase(0), serverBase(0), buffers(NULL), frameCount(0),
1392    loopStart(UINT_MAX), loopEnd(UINT_MAX), loopCount(0), mVolumeLR(0x10001000),
1393    mSendLevel(0), flags(0)
1394{
1395}
1396
1397uint32_t audio_track_cblk_t::stepUser(uint32_t frameCount)
1398{
1399    ALOGV("stepuser %08x %08x %d", user, server, frameCount);
1400
1401    uint32_t u = user;
1402    u += frameCount;
1403    // Ensure that user is never ahead of server for AudioRecord
1404    if (flags & CBLK_DIRECTION_MSK) {
1405        // If stepServer() has been called once, switch to normal obtainBuffer() timeout period
1406        if (bufferTimeoutMs == MAX_STARTUP_TIMEOUT_MS-1) {
1407            bufferTimeoutMs = MAX_RUN_TIMEOUT_MS;
1408        }
1409    } else if (u > server) {
1410        ALOGW("stepUser occurred after track reset");
1411        u = server;
1412    }
1413
1414    uint32_t fc = this->frameCount;
1415    if (u >= fc) {
1416        // common case, user didn't just wrap
1417        if (u - fc >= userBase ) {
1418            userBase += fc;
1419        }
1420    } else if (u >= userBase + fc) {
1421        // user just wrapped
1422        userBase += fc;
1423    }
1424
1425    user = u;
1426
1427    // Clear flow control error condition as new data has been written/read to/from buffer.
1428    if (flags & CBLK_UNDERRUN_MSK) {
1429        android_atomic_and(~CBLK_UNDERRUN_MSK, &flags);
1430    }
1431
1432    return u;
1433}
1434
1435bool audio_track_cblk_t::stepServer(uint32_t frameCount)
1436{
1437    ALOGV("stepserver %08x %08x %d", user, server, frameCount);
1438
1439    if (!tryLock()) {
1440        ALOGW("stepServer() could not lock cblk");
1441        return false;
1442    }
1443
1444    uint32_t s = server;
1445    bool flushed = (s == user);
1446
1447    s += frameCount;
1448    if (flags & CBLK_DIRECTION_MSK) {
1449        // Mark that we have read the first buffer so that next time stepUser() is called
1450        // we switch to normal obtainBuffer() timeout period
1451        if (bufferTimeoutMs == MAX_STARTUP_TIMEOUT_MS) {
1452            bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS - 1;
1453        }
1454        // It is possible that we receive a flush()
1455        // while the mixer is processing a block: in this case,
1456        // stepServer() is called After the flush() has reset u & s and
1457        // we have s > u
1458        if (flushed) {
1459            ALOGW("stepServer occurred after track reset");
1460            s = user;
1461        }
1462    }
1463
1464    if (s >= loopEnd) {
1465        ALOGW_IF(s > loopEnd, "stepServer: s %u > loopEnd %u", s, loopEnd);
1466        s = loopStart;
1467        if (--loopCount == 0) {
1468            loopEnd = UINT_MAX;
1469            loopStart = UINT_MAX;
1470        }
1471    }
1472
1473    uint32_t fc = this->frameCount;
1474    if (s >= fc) {
1475        // common case, server didn't just wrap
1476        if (s - fc >= serverBase ) {
1477            serverBase += fc;
1478        }
1479    } else if (s >= serverBase + fc) {
1480        // server just wrapped
1481        serverBase += fc;
1482    }
1483
1484    server = s;
1485
1486    if (!(flags & CBLK_INVALID_MSK)) {
1487        cv.signal();
1488    }
1489    lock.unlock();
1490    return true;
1491}
1492
1493void* audio_track_cblk_t::buffer(uint32_t offset) const
1494{
1495    return (int8_t *)buffers + (offset - userBase) * frameSize;
1496}
1497
1498uint32_t audio_track_cblk_t::framesAvailable()
1499{
1500    Mutex::Autolock _l(lock);
1501    return framesAvailable_l();
1502}
1503
1504uint32_t audio_track_cblk_t::framesAvailable_l()
1505{
1506    uint32_t u = user;
1507    uint32_t s = server;
1508
1509    if (flags & CBLK_DIRECTION_MSK) {
1510        uint32_t limit = (s < loopStart) ? s : loopStart;
1511        return limit + frameCount - u;
1512    } else {
1513        return frameCount + u - s;
1514    }
1515}
1516
1517uint32_t audio_track_cblk_t::framesReady()
1518{
1519    uint32_t u = user;
1520    uint32_t s = server;
1521
1522    if (flags & CBLK_DIRECTION_MSK) {
1523        if (u < loopEnd) {
1524            return u - s;
1525        } else {
1526            // do not block on mutex shared with client on AudioFlinger side
1527            if (!tryLock()) {
1528                ALOGW("framesReady() could not lock cblk");
1529                return 0;
1530            }
1531            uint32_t frames = UINT_MAX;
1532            if (loopCount >= 0) {
1533                frames = (loopEnd - loopStart)*loopCount + u - s;
1534            }
1535            lock.unlock();
1536            return frames;
1537        }
1538    } else {
1539        return s - u;
1540    }
1541}
1542
1543bool audio_track_cblk_t::tryLock()
1544{
1545    // the code below simulates lock-with-timeout
1546    // we MUST do this to protect the AudioFlinger server
1547    // as this lock is shared with the client.
1548    status_t err;
1549
1550    err = lock.tryLock();
1551    if (err == -EBUSY) { // just wait a bit
1552        usleep(1000);
1553        err = lock.tryLock();
1554    }
1555    if (err != NO_ERROR) {
1556        // probably, the client just died.
1557        return false;
1558    }
1559    return true;
1560}
1561
1562// -------------------------------------------------------------------------
1563
1564}; // namespace android
1565