AudioTrack.cpp revision d1b449aad6c087a69f5ec66b7facb2845b73f1cb 
1/* //device/extlibs/pv/android/AudioTrack.cpp
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 <cutils/atomic.h>
39
40#define LIKELY( exp )       (__builtin_expect( (exp) != 0, true  ))
41#define UNLIKELY( exp )     (__builtin_expect( (exp) != 0, false ))
42
43namespace android {
44
45// ---------------------------------------------------------------------------
46
47AudioTrack::AudioTrack()
48    : mStatus(NO_INIT)
49{
50}
51
52AudioTrack::AudioTrack(
53        int streamType,
54        uint32_t sampleRate,
55        int format,
56        int channels,
57        int frameCount,
58        uint32_t flags,
59        callback_t cbf,
60        void* user,
61        int notificationFrames)
62    : mStatus(NO_INIT)
63{
64    mStatus = set(streamType, sampleRate, format, channels,
65            frameCount, flags, cbf, user, notificationFrames, 0);
66}
67
68AudioTrack::AudioTrack(
69        int streamType,
70        uint32_t sampleRate,
71        int format,
72        int channels,
73        const sp<IMemory>& sharedBuffer,
74        uint32_t flags,
75        callback_t cbf,
76        void* user,
77        int notificationFrames)
78    : mStatus(NO_INIT)
79{
80    mStatus = set(streamType, sampleRate, format, channels,
81            0, flags, cbf, user, notificationFrames, sharedBuffer);
82}
83
84AudioTrack::~AudioTrack()
85{
86    LOGV_IF(mSharedBuffer != 0, "Destructor sharedBuffer: %p", mSharedBuffer->pointer());
87
88    if (mStatus == NO_ERROR) {
89        // Make sure that callback function exits in the case where
90        // it is looping on buffer full condition in obtainBuffer().
91        // Otherwise the callback thread will never exit.
92        stop();
93        if (mAudioTrackThread != 0) {
94            mAudioTrackThread->requestExitAndWait();
95            mAudioTrackThread.clear();
96        }
97        mAudioTrack.clear();
98        IPCThreadState::self()->flushCommands();
99    }
100}
101
102status_t AudioTrack::set(
103        int streamType,
104        uint32_t sampleRate,
105        int format,
106        int channels,
107        int frameCount,
108        uint32_t flags,
109        callback_t cbf,
110        void* user,
111        int notificationFrames,
112        const sp<IMemory>& sharedBuffer,
113        bool threadCanCallJava)
114{
115
116    LOGV_IF(sharedBuffer != 0, "sharedBuffer: %p, size: %d", sharedBuffer->pointer(), sharedBuffer->size());
117
118    if (mAudioTrack != 0) {
119        LOGE("Track already in use");
120        return INVALID_OPERATION;
121    }
122
123    int afSampleRate;
124    if (AudioSystem::getOutputSamplingRate(&afSampleRate, streamType) != NO_ERROR) {
125        return NO_INIT;
126    }
127    uint32_t afLatency;
128    if (AudioSystem::getOutputLatency(&afLatency, streamType) != NO_ERROR) {
129        return NO_INIT;
130    }
131
132    // handle default values first.
133    if (streamType == AudioSystem::DEFAULT) {
134        streamType = AudioSystem::MUSIC;
135    }
136    if (sampleRate == 0) {
137        sampleRate = afSampleRate;
138    }
139    // these below should probably come from the audioFlinger too...
140    if (format == 0) {
141        format = AudioSystem::PCM_16_BIT;
142    }
143    if (channels == 0) {
144        channels = AudioSystem::CHANNEL_OUT_STEREO;
145    }
146
147    // validate parameters
148    if (!AudioSystem::isValidFormat(format)) {
149        LOGE("Invalid format");
150        return BAD_VALUE;
151    }
152
153    // force direct flag if format is not linear PCM
154    if (!AudioSystem::isLinearPCM(format)) {
155        flags |= AudioSystem::OUTPUT_FLAG_DIRECT;
156    }
157
158    if (!AudioSystem::isOutputChannel(channels)) {
159        LOGE("Invalid channel mask");
160        return BAD_VALUE;
161    }
162    uint32_t channelCount = AudioSystem::popCount(channels);
163
164    audio_io_handle_t output = AudioSystem::getOutput((AudioSystem::stream_type)streamType,
165            sampleRate, format, channels, (AudioSystem::output_flags)flags);
166
167    if (output == 0) {
168        LOGE("Could not get audio output for stream type %d", streamType);
169        return BAD_VALUE;
170    }
171
172    mVolume[LEFT] = 1.0f;
173    mVolume[RIGHT] = 1.0f;
174    mFrameCount = frameCount;
175    mNotificationFramesReq = notificationFrames;
176    // create the IAudioTrack
177    status_t status = createTrack(streamType, sampleRate, format, channelCount,
178                                  frameCount, flags, sharedBuffer, output, true);
179
180    if (status != NO_ERROR) {
181        return status;
182    }
183
184    if (cbf != 0) {
185        mAudioTrackThread = new AudioTrackThread(*this, threadCanCallJava);
186        if (mAudioTrackThread == 0) {
187          LOGE("Could not create callback thread");
188          return NO_INIT;
189        }
190    }
191
192    mStatus = NO_ERROR;
193
194    mStreamType = streamType;
195    mFormat = format;
196    mChannels = channels;
197    mChannelCount = channelCount;
198    mSharedBuffer = sharedBuffer;
199    mMuted = false;
200    mActive = 0;
201    mCbf = cbf;
202    mUserData = user;
203    mLoopCount = 0;
204    mMarkerPosition = 0;
205    mMarkerReached = false;
206    mNewPosition = 0;
207    mUpdatePeriod = 0;
208    mFlags = flags;
209
210    return NO_ERROR;
211}
212
213status_t AudioTrack::initCheck() const
214{
215    return mStatus;
216}
217
218// -------------------------------------------------------------------------
219
220uint32_t AudioTrack::latency() const
221{
222    return mLatency;
223}
224
225int AudioTrack::streamType() const
226{
227    return mStreamType;
228}
229
230int AudioTrack::format() const
231{
232    return mFormat;
233}
234
235int AudioTrack::channelCount() const
236{
237    return mChannelCount;
238}
239
240uint32_t AudioTrack::frameCount() const
241{
242    return mCblk->frameCount;
243}
244
245int AudioTrack::frameSize() const
246{
247    if (AudioSystem::isLinearPCM(mFormat)) {
248        return channelCount()*((format() == AudioSystem::PCM_8_BIT) ? sizeof(uint8_t) : sizeof(int16_t));
249    } else {
250        return sizeof(uint8_t);
251    }
252}
253
254sp<IMemory>& AudioTrack::sharedBuffer()
255{
256    return mSharedBuffer;
257}
258
259// -------------------------------------------------------------------------
260
261void AudioTrack::start()
262{
263    sp<AudioTrackThread> t = mAudioTrackThread;
264    status_t status;
265
266    LOGV("start %p", this);
267    if (t != 0) {
268        if (t->exitPending()) {
269            if (t->requestExitAndWait() == WOULD_BLOCK) {
270                LOGE("AudioTrack::start called from thread");
271                return;
272            }
273        }
274        t->mLock.lock();
275     }
276
277    if (android_atomic_or(1, &mActive) == 0) {
278        mNewPosition = mCblk->server + mUpdatePeriod;
279        mCblk->bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS;
280        mCblk->waitTimeMs = 0;
281        if (t != 0) {
282           t->run("AudioTrackThread", THREAD_PRIORITY_AUDIO_CLIENT);
283        } else {
284            setpriority(PRIO_PROCESS, 0, THREAD_PRIORITY_AUDIO_CLIENT);
285        }
286
287        if (mCblk->flags & CBLK_INVALID_MSK) {
288            LOGW("start() track %p invalidated, creating a new one", this);
289            // no need to clear the invalid flag as this cblk will not be used anymore
290            // force new track creation
291            status = DEAD_OBJECT;
292        } else {
293            status = mAudioTrack->start();
294        }
295        if (status == DEAD_OBJECT) {
296            LOGV("start() dead IAudioTrack: creating a new one");
297            status = createTrack(mStreamType, mCblk->sampleRate, mFormat, mChannelCount,
298                                 mFrameCount, mFlags, mSharedBuffer, getOutput(), false);
299            if (status == NO_ERROR) {
300                status = mAudioTrack->start();
301                if (status == NO_ERROR) {
302                    mNewPosition = mCblk->server + mUpdatePeriod;
303                }
304            }
305        }
306        if (status != NO_ERROR) {
307            LOGV("start() failed");
308            android_atomic_and(~1, &mActive);
309            if (t != 0) {
310                t->requestExit();
311            } else {
312                setpriority(PRIO_PROCESS, 0, ANDROID_PRIORITY_NORMAL);
313            }
314        }
315    }
316
317    if (t != 0) {
318        t->mLock.unlock();
319    }
320}
321
322void AudioTrack::stop()
323{
324    sp<AudioTrackThread> t = mAudioTrackThread;
325
326    LOGV("stop %p", this);
327    if (t != 0) {
328        t->mLock.lock();
329    }
330
331    if (android_atomic_and(~1, &mActive) == 1) {
332        mCblk->cv.signal();
333        mAudioTrack->stop();
334        // Cancel loops (If we are in the middle of a loop, playback
335        // would not stop until loopCount reaches 0).
336        setLoop(0, 0, 0);
337        // the playback head position will reset to 0, so if a marker is set, we need
338        // to activate it again
339        mMarkerReached = false;
340        // Force flush if a shared buffer is used otherwise audioflinger
341        // will not stop before end of buffer is reached.
342        if (mSharedBuffer != 0) {
343            flush();
344        }
345        if (t != 0) {
346            t->requestExit();
347        } else {
348            setpriority(PRIO_PROCESS, 0, ANDROID_PRIORITY_NORMAL);
349        }
350    }
351
352    if (t != 0) {
353        t->mLock.unlock();
354    }
355}
356
357bool AudioTrack::stopped() const
358{
359    return !mActive;
360}
361
362void AudioTrack::flush()
363{
364    LOGV("flush");
365
366    // clear playback marker and periodic update counter
367    mMarkerPosition = 0;
368    mMarkerReached = false;
369    mUpdatePeriod = 0;
370
371
372    if (!mActive) {
373        mAudioTrack->flush();
374        // Release AudioTrack callback thread in case it was waiting for new buffers
375        // in AudioTrack::obtainBuffer()
376        mCblk->cv.signal();
377    }
378}
379
380void AudioTrack::pause()
381{
382    LOGV("pause");
383    if (android_atomic_and(~1, &mActive) == 1) {
384        mAudioTrack->pause();
385    }
386}
387
388void AudioTrack::mute(bool e)
389{
390    mAudioTrack->mute(e);
391    mMuted = e;
392}
393
394bool AudioTrack::muted() const
395{
396    return mMuted;
397}
398
399void AudioTrack::setVolume(float left, float right)
400{
401    mVolume[LEFT] = left;
402    mVolume[RIGHT] = right;
403
404    // write must be atomic
405    mCblk->volumeLR = (int32_t(int16_t(left * 0x1000)) << 16) | int16_t(right * 0x1000);
406}
407
408void AudioTrack::getVolume(float* left, float* right)
409{
410    *left  = mVolume[LEFT];
411    *right = mVolume[RIGHT];
412}
413
414status_t AudioTrack::setSampleRate(int rate)
415{
416    int afSamplingRate;
417
418    if (AudioSystem::getOutputSamplingRate(&afSamplingRate, mStreamType) != NO_ERROR) {
419        return NO_INIT;
420    }
421    // Resampler implementation limits input sampling rate to 2 x output sampling rate.
422    if (rate <= 0 || rate > afSamplingRate*2 ) return BAD_VALUE;
423
424    mCblk->sampleRate = rate;
425    return NO_ERROR;
426}
427
428uint32_t AudioTrack::getSampleRate()
429{
430    return mCblk->sampleRate;
431}
432
433status_t AudioTrack::setLoop(uint32_t loopStart, uint32_t loopEnd, int loopCount)
434{
435    audio_track_cblk_t* cblk = mCblk;
436
437    Mutex::Autolock _l(cblk->lock);
438
439    if (loopCount == 0) {
440        cblk->loopStart = UINT_MAX;
441        cblk->loopEnd = UINT_MAX;
442        cblk->loopCount = 0;
443        mLoopCount = 0;
444        return NO_ERROR;
445    }
446
447    if (loopStart >= loopEnd ||
448        loopEnd - loopStart > cblk->frameCount) {
449        LOGE("setLoop invalid value: loopStart %d, loopEnd %d, loopCount %d, framecount %d, user %d", loopStart, loopEnd, loopCount, cblk->frameCount, cblk->user);
450        return BAD_VALUE;
451    }
452
453    if ((mSharedBuffer != 0) && (loopEnd   > cblk->frameCount)) {
454        LOGE("setLoop invalid value: loop markers beyond data: loopStart %d, loopEnd %d, framecount %d",
455            loopStart, loopEnd, cblk->frameCount);
456        return BAD_VALUE;
457    }
458
459    cblk->loopStart = loopStart;
460    cblk->loopEnd = loopEnd;
461    cblk->loopCount = loopCount;
462    mLoopCount = loopCount;
463
464    return NO_ERROR;
465}
466
467status_t AudioTrack::getLoop(uint32_t *loopStart, uint32_t *loopEnd, int *loopCount)
468{
469    if (loopStart != 0) {
470        *loopStart = mCblk->loopStart;
471    }
472    if (loopEnd != 0) {
473        *loopEnd = mCblk->loopEnd;
474    }
475    if (loopCount != 0) {
476        if (mCblk->loopCount < 0) {
477            *loopCount = -1;
478        } else {
479            *loopCount = mCblk->loopCount;
480        }
481    }
482
483    return NO_ERROR;
484}
485
486status_t AudioTrack::setMarkerPosition(uint32_t marker)
487{
488    if (mCbf == 0) return INVALID_OPERATION;
489
490    mMarkerPosition = marker;
491    mMarkerReached = false;
492
493    return NO_ERROR;
494}
495
496status_t AudioTrack::getMarkerPosition(uint32_t *marker)
497{
498    if (marker == 0) return BAD_VALUE;
499
500    *marker = mMarkerPosition;
501
502    return NO_ERROR;
503}
504
505status_t AudioTrack::setPositionUpdatePeriod(uint32_t updatePeriod)
506{
507    if (mCbf == 0) return INVALID_OPERATION;
508
509    uint32_t curPosition;
510    getPosition(&curPosition);
511    mNewPosition = curPosition + updatePeriod;
512    mUpdatePeriod = updatePeriod;
513
514    return NO_ERROR;
515}
516
517status_t AudioTrack::getPositionUpdatePeriod(uint32_t *updatePeriod)
518{
519    if (updatePeriod == 0) return BAD_VALUE;
520
521    *updatePeriod = mUpdatePeriod;
522
523    return NO_ERROR;
524}
525
526status_t AudioTrack::setPosition(uint32_t position)
527{
528    Mutex::Autolock _l(mCblk->lock);
529
530    if (!stopped()) return INVALID_OPERATION;
531
532    if (position > mCblk->user) return BAD_VALUE;
533
534    mCblk->server = position;
535    mCblk->flags |= CBLK_FORCEREADY_ON;
536
537    return NO_ERROR;
538}
539
540status_t AudioTrack::getPosition(uint32_t *position)
541{
542    if (position == 0) return BAD_VALUE;
543
544    *position = mCblk->server;
545
546    return NO_ERROR;
547}
548
549status_t AudioTrack::reload()
550{
551    if (!stopped()) return INVALID_OPERATION;
552
553    flush();
554
555    mCblk->stepUser(mCblk->frameCount);
556
557    return NO_ERROR;
558}
559
560audio_io_handle_t AudioTrack::getOutput()
561{
562    return AudioSystem::getOutput((AudioSystem::stream_type)mStreamType,
563            mCblk->sampleRate, mFormat, mChannels, (AudioSystem::output_flags)mFlags);
564}
565
566// -------------------------------------------------------------------------
567
568status_t AudioTrack::createTrack(
569        int streamType,
570        uint32_t sampleRate,
571        int format,
572        int channelCount,
573        int frameCount,
574        uint32_t flags,
575        const sp<IMemory>& sharedBuffer,
576        audio_io_handle_t output,
577        bool enforceFrameCount)
578{
579    status_t status;
580    const sp<IAudioFlinger>& audioFlinger = AudioSystem::get_audio_flinger();
581    if (audioFlinger == 0) {
582       LOGE("Could not get audioflinger");
583       return NO_INIT;
584    }
585
586    int afSampleRate;
587    if (AudioSystem::getOutputSamplingRate(&afSampleRate, streamType) != NO_ERROR) {
588        return NO_INIT;
589    }
590    int afFrameCount;
591    if (AudioSystem::getOutputFrameCount(&afFrameCount, streamType) != NO_ERROR) {
592        return NO_INIT;
593    }
594    uint32_t afLatency;
595    if (AudioSystem::getOutputLatency(&afLatency, streamType) != NO_ERROR) {
596        return NO_INIT;
597    }
598
599    mNotificationFramesAct = mNotificationFramesReq;
600    if (!AudioSystem::isLinearPCM(format)) {
601        if (sharedBuffer != 0) {
602            frameCount = sharedBuffer->size();
603        }
604    } else {
605        // Ensure that buffer depth covers at least audio hardware latency
606        uint32_t minBufCount = afLatency / ((1000 * afFrameCount)/afSampleRate);
607        if (minBufCount < 2) minBufCount = 2;
608
609        int minFrameCount = (afFrameCount*sampleRate*minBufCount)/afSampleRate;
610
611        if (sharedBuffer == 0) {
612            if (frameCount == 0) {
613                frameCount = minFrameCount;
614            }
615            if (mNotificationFramesAct == 0) {
616                mNotificationFramesAct = frameCount/2;
617            }
618            // Make sure that application is notified with sufficient margin
619            // before underrun
620            if (mNotificationFramesAct > (uint32_t)frameCount/2) {
621                mNotificationFramesAct = frameCount/2;
622            }
623            if (frameCount < minFrameCount) {
624                if (enforceFrameCount) {
625                    LOGE("Invalid buffer size: minFrameCount %d, frameCount %d", minFrameCount, frameCount);
626                    return BAD_VALUE;
627                } else {
628                    frameCount = minFrameCount;
629                }
630            }
631        } else {
632            // Ensure that buffer alignment matches channelcount
633            if (((uint32_t)sharedBuffer->pointer() & (channelCount | 1)) != 0) {
634                LOGE("Invalid buffer alignement: address %p, channelCount %d", sharedBuffer->pointer(), channelCount);
635                return BAD_VALUE;
636            }
637            frameCount = sharedBuffer->size()/channelCount/sizeof(int16_t);
638        }
639    }
640
641    sp<IAudioTrack> track = audioFlinger->createTrack(getpid(),
642                                                      streamType,
643                                                      sampleRate,
644                                                      format,
645                                                      channelCount,
646                                                      frameCount,
647                                                      ((uint16_t)flags) << 16,
648                                                      sharedBuffer,
649                                                      output,
650                                                      &status);
651
652    if (track == 0) {
653        LOGE("AudioFlinger could not create track, status: %d", status);
654        return status;
655    }
656    sp<IMemory> cblk = track->getCblk();
657    if (cblk == 0) {
658        LOGE("Could not get control block");
659        return NO_INIT;
660    }
661    mAudioTrack.clear();
662    mAudioTrack = track;
663    mCblkMemory.clear();
664    mCblkMemory = cblk;
665    mCblk = static_cast<audio_track_cblk_t*>(cblk->pointer());
666    mCblk->flags |= CBLK_DIRECTION_OUT;
667    if (sharedBuffer == 0) {
668        mCblk->buffers = (char*)mCblk + sizeof(audio_track_cblk_t);
669    } else {
670        mCblk->buffers = sharedBuffer->pointer();
671         // Force buffer full condition as data is already present in shared memory
672        mCblk->stepUser(mCblk->frameCount);
673    }
674
675    mCblk->volumeLR = (int32_t(int16_t(mVolume[LEFT] * 0x1000)) << 16) | int16_t(mVolume[RIGHT] * 0x1000);
676    mCblk->bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS;
677    mCblk->waitTimeMs = 0;
678    mRemainingFrames = mNotificationFramesAct;
679    mLatency = afLatency + (1000*mCblk->frameCount) / sampleRate;
680    return NO_ERROR;
681}
682
683status_t AudioTrack::obtainBuffer(Buffer* audioBuffer, int32_t waitCount)
684{
685    int active;
686    status_t result;
687    audio_track_cblk_t* cblk = mCblk;
688    uint32_t framesReq = audioBuffer->frameCount;
689    uint32_t waitTimeMs = (waitCount < 0) ? cblk->bufferTimeoutMs : WAIT_PERIOD_MS;
690
691    audioBuffer->frameCount  = 0;
692    audioBuffer->size = 0;
693
694    uint32_t framesAvail = cblk->framesAvailable();
695
696    if (framesAvail == 0) {
697        cblk->lock.lock();
698        goto start_loop_here;
699        while (framesAvail == 0) {
700            active = mActive;
701            if (UNLIKELY(!active)) {
702                LOGV("Not active and NO_MORE_BUFFERS");
703                cblk->lock.unlock();
704                return NO_MORE_BUFFERS;
705            }
706            if (UNLIKELY(!waitCount)) {
707                cblk->lock.unlock();
708                return WOULD_BLOCK;
709            }
710            if (!(cblk->flags & CBLK_INVALID_MSK)) {
711                result = cblk->cv.waitRelative(cblk->lock, milliseconds(waitTimeMs));
712            }
713            if (cblk->flags & CBLK_INVALID_MSK) {
714                LOGW("obtainBuffer() track %p invalidated, creating a new one", this);
715                // no need to clear the invalid flag as this cblk will not be used anymore
716                cblk->lock.unlock();
717                goto create_new_track;
718            }
719            if (__builtin_expect(result!=NO_ERROR, false)) {
720                cblk->waitTimeMs += waitTimeMs;
721                if (cblk->waitTimeMs >= cblk->bufferTimeoutMs) {
722                    // timing out when a loop has been set and we have already written upto loop end
723                    // is a normal condition: no need to wake AudioFlinger up.
724                    if (cblk->user < cblk->loopEnd) {
725                        LOGW(   "obtainBuffer timed out (is the CPU pegged?) %p "
726                                "user=%08x, server=%08x", this, cblk->user, cblk->server);
727                        //unlock cblk mutex before calling mAudioTrack->start() (see issue #1617140)
728                        cblk->lock.unlock();
729                        result = mAudioTrack->start();
730                        if (result == DEAD_OBJECT) {
731                            LOGW("obtainBuffer() dead IAudioTrack: creating a new one");
732create_new_track:
733                            result = createTrack(mStreamType, cblk->sampleRate, mFormat, mChannelCount,
734                                                 mFrameCount, mFlags, mSharedBuffer, getOutput(), false);
735                            if (result == NO_ERROR) {
736                                cblk = mCblk;
737                                cblk->bufferTimeoutMs = MAX_RUN_TIMEOUT_MS;
738                                mAudioTrack->start();
739                            }
740                        }
741                        cblk->lock.lock();
742                    }
743                    cblk->waitTimeMs = 0;
744                }
745
746                if (--waitCount == 0) {
747                    cblk->lock.unlock();
748                    return TIMED_OUT;
749                }
750            }
751            // read the server count again
752        start_loop_here:
753            framesAvail = cblk->framesAvailable_l();
754        }
755        cblk->lock.unlock();
756    }
757
758    cblk->waitTimeMs = 0;
759
760    if (framesReq > framesAvail) {
761        framesReq = framesAvail;
762    }
763
764    uint32_t u = cblk->user;
765    uint32_t bufferEnd = cblk->userBase + cblk->frameCount;
766
767    if (u + framesReq > bufferEnd) {
768        framesReq = bufferEnd - u;
769    }
770
771    audioBuffer->flags = mMuted ? Buffer::MUTE : 0;
772    audioBuffer->channelCount = mChannelCount;
773    audioBuffer->frameCount = framesReq;
774    audioBuffer->size = framesReq * cblk->frameSize;
775    if (AudioSystem::isLinearPCM(mFormat)) {
776        audioBuffer->format = AudioSystem::PCM_16_BIT;
777    } else {
778        audioBuffer->format = mFormat;
779    }
780    audioBuffer->raw = (int8_t *)cblk->buffer(u);
781    active = mActive;
782    return active ? status_t(NO_ERROR) : status_t(STOPPED);
783}
784
785void AudioTrack::releaseBuffer(Buffer* audioBuffer)
786{
787    audio_track_cblk_t* cblk = mCblk;
788    cblk->stepUser(audioBuffer->frameCount);
789}
790
791// -------------------------------------------------------------------------
792
793ssize_t AudioTrack::write(const void* buffer, size_t userSize)
794{
795
796    if (mSharedBuffer != 0) return INVALID_OPERATION;
797
798    if (ssize_t(userSize) < 0) {
799        // sanity-check. user is most-likely passing an error code.
800        LOGE("AudioTrack::write(buffer=%p, size=%u (%d)",
801                buffer, userSize, userSize);
802        return BAD_VALUE;
803    }
804
805    LOGV("write %p: %d bytes, mActive=%d", this, userSize, mActive);
806
807    ssize_t written = 0;
808    const int8_t *src = (const int8_t *)buffer;
809    Buffer audioBuffer;
810
811    do {
812        audioBuffer.frameCount = userSize/frameSize();
813
814        // Calling obtainBuffer() with a negative wait count causes
815        // an (almost) infinite wait time.
816        status_t err = obtainBuffer(&audioBuffer, -1);
817        if (err < 0) {
818            // out of buffers, return #bytes written
819            if (err == status_t(NO_MORE_BUFFERS))
820                break;
821            return ssize_t(err);
822        }
823
824        size_t toWrite;
825
826        if (mFormat == AudioSystem::PCM_8_BIT && !(mFlags & AudioSystem::OUTPUT_FLAG_DIRECT)) {
827            // Divide capacity by 2 to take expansion into account
828            toWrite = audioBuffer.size>>1;
829            // 8 to 16 bit conversion
830            int count = toWrite;
831            int16_t *dst = (int16_t *)(audioBuffer.i8);
832            while(count--) {
833                *dst++ = (int16_t)(*src++^0x80) << 8;
834            }
835        } else {
836            toWrite = audioBuffer.size;
837            memcpy(audioBuffer.i8, src, toWrite);
838            src += toWrite;
839        }
840        userSize -= toWrite;
841        written += toWrite;
842
843        releaseBuffer(&audioBuffer);
844    } while (userSize);
845
846    return written;
847}
848
849// -------------------------------------------------------------------------
850
851bool AudioTrack::processAudioBuffer(const sp<AudioTrackThread>& thread)
852{
853    Buffer audioBuffer;
854    uint32_t frames;
855    size_t writtenSize;
856
857    // Manage underrun callback
858    if (mActive && (mCblk->framesReady() == 0)) {
859        LOGV("Underrun user: %x, server: %x, flags %04x", mCblk->user, mCblk->server, mCblk->flags);
860        if ((mCblk->flags & CBLK_UNDERRUN_MSK) == CBLK_UNDERRUN_OFF) {
861            mCbf(EVENT_UNDERRUN, mUserData, 0);
862            if (mCblk->server == mCblk->frameCount) {
863                mCbf(EVENT_BUFFER_END, mUserData, 0);
864            }
865            mCblk->flags |= CBLK_UNDERRUN_ON;
866            if (mSharedBuffer != 0) return false;
867        }
868    }
869
870    // Manage loop end callback
871    while (mLoopCount > mCblk->loopCount) {
872        int loopCount = -1;
873        mLoopCount--;
874        if (mLoopCount >= 0) loopCount = mLoopCount;
875
876        mCbf(EVENT_LOOP_END, mUserData, (void *)&loopCount);
877    }
878
879    // Manage marker callback
880    if (!mMarkerReached && (mMarkerPosition > 0)) {
881        if (mCblk->server >= mMarkerPosition) {
882            mCbf(EVENT_MARKER, mUserData, (void *)&mMarkerPosition);
883            mMarkerReached = true;
884        }
885    }
886
887    // Manage new position callback
888    if (mUpdatePeriod > 0) {
889        while (mCblk->server >= mNewPosition) {
890            mCbf(EVENT_NEW_POS, mUserData, (void *)&mNewPosition);
891            mNewPosition += mUpdatePeriod;
892        }
893    }
894
895    // If Shared buffer is used, no data is requested from client.
896    if (mSharedBuffer != 0) {
897        frames = 0;
898    } else {
899        frames = mRemainingFrames;
900    }
901
902    do {
903
904        audioBuffer.frameCount = frames;
905
906        // Calling obtainBuffer() with a wait count of 1
907        // limits wait time to WAIT_PERIOD_MS. This prevents from being
908        // stuck here not being able to handle timed events (position, markers, loops).
909        status_t err = obtainBuffer(&audioBuffer, 1);
910        if (err < NO_ERROR) {
911            if (err != TIMED_OUT) {
912                LOGE_IF(err != status_t(NO_MORE_BUFFERS), "Error obtaining an audio buffer, giving up.");
913                return false;
914            }
915            break;
916        }
917        if (err == status_t(STOPPED)) return false;
918
919        // Divide buffer size by 2 to take into account the expansion
920        // due to 8 to 16 bit conversion: the callback must fill only half
921        // of the destination buffer
922        if (mFormat == AudioSystem::PCM_8_BIT && !(mFlags & AudioSystem::OUTPUT_FLAG_DIRECT)) {
923            audioBuffer.size >>= 1;
924        }
925
926        size_t reqSize = audioBuffer.size;
927        mCbf(EVENT_MORE_DATA, mUserData, &audioBuffer);
928        writtenSize = audioBuffer.size;
929
930        // Sanity check on returned size
931        if (ssize_t(writtenSize) <= 0) {
932            // The callback is done filling buffers
933            // Keep this thread going to handle timed events and
934            // still try to get more data in intervals of WAIT_PERIOD_MS
935            // but don't just loop and block the CPU, so wait
936            usleep(WAIT_PERIOD_MS*1000);
937            break;
938        }
939        if (writtenSize > reqSize) writtenSize = reqSize;
940
941        if (mFormat == AudioSystem::PCM_8_BIT && !(mFlags & AudioSystem::OUTPUT_FLAG_DIRECT)) {
942            // 8 to 16 bit conversion
943            const int8_t *src = audioBuffer.i8 + writtenSize-1;
944            int count = writtenSize;
945            int16_t *dst = audioBuffer.i16 + writtenSize-1;
946            while(count--) {
947                *dst-- = (int16_t)(*src--^0x80) << 8;
948            }
949            writtenSize <<= 1;
950        }
951
952        audioBuffer.size = writtenSize;
953        // NOTE: mCblk->frameSize is not equal to AudioTrack::frameSize() for
954        // 8 bit PCM data: in this case,  mCblk->frameSize is based on a sampel size of
955        // 16 bit.
956        audioBuffer.frameCount = writtenSize/mCblk->frameSize;
957
958        frames -= audioBuffer.frameCount;
959
960        releaseBuffer(&audioBuffer);
961    }
962    while (frames);
963
964    if (frames == 0) {
965        mRemainingFrames = mNotificationFramesAct;
966    } else {
967        mRemainingFrames = frames;
968    }
969    return true;
970}
971
972status_t AudioTrack::dump(int fd, const Vector<String16>& args) const
973{
974
975    const size_t SIZE = 256;
976    char buffer[SIZE];
977    String8 result;
978
979    result.append(" AudioTrack::dump\n");
980    snprintf(buffer, 255, "  stream type(%d), left - right volume(%f, %f)\n", mStreamType, mVolume[0], mVolume[1]);
981    result.append(buffer);
982    snprintf(buffer, 255, "  format(%d), channel count(%d), frame count(%d)\n", mFormat, mChannelCount, mCblk->frameCount);
983    result.append(buffer);
984    snprintf(buffer, 255, "  sample rate(%d), status(%d), muted(%d)\n", (mCblk == 0) ? 0 : mCblk->sampleRate, mStatus, mMuted);
985    result.append(buffer);
986    snprintf(buffer, 255, "  active(%d), latency (%d)\n", mActive, mLatency);
987    result.append(buffer);
988    ::write(fd, result.string(), result.size());
989    return NO_ERROR;
990}
991
992// =========================================================================
993
994AudioTrack::AudioTrackThread::AudioTrackThread(AudioTrack& receiver, bool bCanCallJava)
995    : Thread(bCanCallJava), mReceiver(receiver)
996{
997}
998
999bool AudioTrack::AudioTrackThread::threadLoop()
1000{
1001    return mReceiver.processAudioBuffer(this);
1002}
1003
1004status_t AudioTrack::AudioTrackThread::readyToRun()
1005{
1006    return NO_ERROR;
1007}
1008
1009void AudioTrack::AudioTrackThread::onFirstRef()
1010{
1011}
1012
1013// =========================================================================
1014
1015audio_track_cblk_t::audio_track_cblk_t()
1016    : lock(Mutex::SHARED), cv(Condition::SHARED), user(0), server(0),
1017    userBase(0), serverBase(0), buffers(0), frameCount(0),
1018    loopStart(UINT_MAX), loopEnd(UINT_MAX), loopCount(0), volumeLR(0),
1019    flags(0)
1020{
1021}
1022
1023uint32_t audio_track_cblk_t::stepUser(uint32_t frameCount)
1024{
1025    uint32_t u = this->user;
1026
1027    u += frameCount;
1028    // Ensure that user is never ahead of server for AudioRecord
1029    if (flags & CBLK_DIRECTION_MSK) {
1030        // If stepServer() has been called once, switch to normal obtainBuffer() timeout period
1031        if (bufferTimeoutMs == MAX_STARTUP_TIMEOUT_MS-1) {
1032            bufferTimeoutMs = MAX_RUN_TIMEOUT_MS;
1033        }
1034    } else if (u > this->server) {
1035        LOGW("stepServer occured after track reset");
1036        u = this->server;
1037    }
1038
1039    if (u >= userBase + this->frameCount) {
1040        userBase += this->frameCount;
1041    }
1042
1043    this->user = u;
1044
1045    // Clear flow control error condition as new data has been written/read to/from buffer.
1046    flags &= ~CBLK_UNDERRUN_MSK;
1047
1048    return u;
1049}
1050
1051bool audio_track_cblk_t::stepServer(uint32_t frameCount)
1052{
1053    // the code below simulates lock-with-timeout
1054    // we MUST do this to protect the AudioFlinger server
1055    // as this lock is shared with the client.
1056    status_t err;
1057
1058    err = lock.tryLock();
1059    if (err == -EBUSY) { // just wait a bit
1060        usleep(1000);
1061        err = lock.tryLock();
1062    }
1063    if (err != NO_ERROR) {
1064        // probably, the client just died.
1065        return false;
1066    }
1067
1068    uint32_t s = this->server;
1069
1070    s += frameCount;
1071    if (flags & CBLK_DIRECTION_MSK) {
1072        // Mark that we have read the first buffer so that next time stepUser() is called
1073        // we switch to normal obtainBuffer() timeout period
1074        if (bufferTimeoutMs == MAX_STARTUP_TIMEOUT_MS) {
1075            bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS - 1;
1076        }
1077        // It is possible that we receive a flush()
1078        // while the mixer is processing a block: in this case,
1079        // stepServer() is called After the flush() has reset u & s and
1080        // we have s > u
1081        if (s > this->user) {
1082            LOGW("stepServer occured after track reset");
1083            s = this->user;
1084        }
1085    }
1086
1087    if (s >= loopEnd) {
1088        LOGW_IF(s > loopEnd, "stepServer: s %u > loopEnd %u", s, loopEnd);
1089        s = loopStart;
1090        if (--loopCount == 0) {
1091            loopEnd = UINT_MAX;
1092            loopStart = UINT_MAX;
1093        }
1094    }
1095    if (s >= serverBase + this->frameCount) {
1096        serverBase += this->frameCount;
1097    }
1098
1099    this->server = s;
1100
1101    cv.signal();
1102    lock.unlock();
1103    return true;
1104}
1105
1106void* audio_track_cblk_t::buffer(uint32_t offset) const
1107{
1108    return (int8_t *)this->buffers + (offset - userBase) * this->frameSize;
1109}
1110
1111uint32_t audio_track_cblk_t::framesAvailable()
1112{
1113    Mutex::Autolock _l(lock);
1114    return framesAvailable_l();
1115}
1116
1117uint32_t audio_track_cblk_t::framesAvailable_l()
1118{
1119    uint32_t u = this->user;
1120    uint32_t s = this->server;
1121
1122    if (flags & CBLK_DIRECTION_MSK) {
1123        uint32_t limit = (s < loopStart) ? s : loopStart;
1124        return limit + frameCount - u;
1125    } else {
1126        return frameCount + u - s;
1127    }
1128}
1129
1130uint32_t audio_track_cblk_t::framesReady()
1131{
1132    uint32_t u = this->user;
1133    uint32_t s = this->server;
1134
1135    if (flags & CBLK_DIRECTION_MSK) {
1136        if (u < loopEnd) {
1137            return u - s;
1138        } else {
1139            Mutex::Autolock _l(lock);
1140            if (loopCount >= 0) {
1141                return (loopEnd - loopStart)*loopCount + u - s;
1142            } else {
1143                return UINT_MAX;
1144            }
1145        }
1146    } else {
1147        return s - u;
1148    }
1149}
1150
1151// -------------------------------------------------------------------------
1152
1153}; // namespace android
1154
1155