AudioRecord.cpp revision 868a6a357018e5872e064b7a13a9b891e2078962 
1/*
2**
3** Copyright 2008, 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//#define LOG_NDEBUG 0
19#define LOG_TAG "AudioRecord"
20
21#include <sys/resource.h>
22#include <sys/types.h>
23
24#include <binder/IPCThreadState.h>
25#include <cutils/atomic.h>
26#include <cutils/compiler.h>
27#include <media/AudioRecord.h>
28#include <media/AudioSystem.h>
29#include <system/audio.h>
30#include <utils/Log.h>
31
32#include <private/media/AudioTrackShared.h>
33
34namespace android {
35// ---------------------------------------------------------------------------
36
37// static
38status_t AudioRecord::getMinFrameCount(
39        int* frameCount,
40        uint32_t sampleRate,
41        audio_format_t format,
42        int channelCount)
43{
44    size_t size = 0;
45    if (AudioSystem::getInputBufferSize(sampleRate, format, channelCount, &size)
46            != NO_ERROR) {
47        ALOGE("AudioSystem could not query the input buffer size.");
48        return NO_INIT;
49    }
50
51    if (size == 0) {
52        ALOGE("Unsupported configuration: sampleRate %d, format %d, channelCount %d",
53            sampleRate, format, channelCount);
54        return BAD_VALUE;
55    }
56
57    // We double the size of input buffer for ping pong use of record buffer.
58    size <<= 1;
59
60    if (audio_is_linear_pcm(format)) {
61        size /= channelCount * audio_bytes_per_sample(format);
62    }
63
64    *frameCount = size;
65    return NO_ERROR;
66}
67
68// ---------------------------------------------------------------------------
69
70AudioRecord::AudioRecord()
71    : mStatus(NO_INIT), mSessionId(0),
72      mPreviousPriority(ANDROID_PRIORITY_NORMAL), mPreviousSchedulingGroup(SP_DEFAULT)
73{
74}
75
76AudioRecord::AudioRecord(
77        audio_source_t inputSource,
78        uint32_t sampleRate,
79        audio_format_t format,
80        uint32_t channelMask,
81        int frameCount,
82        callback_t cbf,
83        void* user,
84        int notificationFrames,
85        int sessionId)
86    : mStatus(NO_INIT), mSessionId(0),
87      mPreviousPriority(ANDROID_PRIORITY_NORMAL), mPreviousSchedulingGroup(SP_DEFAULT)
88{
89    mStatus = set(inputSource, sampleRate, format, channelMask,
90            frameCount, cbf, user, notificationFrames, sessionId);
91}
92
93AudioRecord::~AudioRecord()
94{
95    if (mStatus == NO_ERROR) {
96        // Make sure that callback function exits in the case where
97        // it is looping on buffer empty condition in obtainBuffer().
98        // Otherwise the callback thread will never exit.
99        stop();
100        if (mClientRecordThread != 0) {
101            mClientRecordThread->requestExitAndWait();
102            mClientRecordThread.clear();
103        }
104        mAudioRecord.clear();
105        IPCThreadState::self()->flushCommands();
106        AudioSystem::releaseAudioSessionId(mSessionId);
107    }
108}
109
110status_t AudioRecord::set(
111        audio_source_t inputSource,
112        uint32_t sampleRate,
113        audio_format_t format,
114        uint32_t channelMask,
115        int frameCount,
116        callback_t cbf,
117        void* user,
118        int notificationFrames,
119        bool threadCanCallJava,
120        int sessionId)
121{
122
123    ALOGV("set(): sampleRate %d, channelMask %d, frameCount %d",sampleRate, channelMask, frameCount);
124
125    AutoMutex lock(mLock);
126
127    if (mAudioRecord != 0) {
128        return INVALID_OPERATION;
129    }
130
131    if (inputSource == AUDIO_SOURCE_DEFAULT) {
132        inputSource = AUDIO_SOURCE_MIC;
133    }
134
135    if (sampleRate == 0) {
136        sampleRate = DEFAULT_SAMPLE_RATE;
137    }
138    // these below should probably come from the audioFlinger too...
139    if (format == AUDIO_FORMAT_DEFAULT) {
140        format = AUDIO_FORMAT_PCM_16_BIT;
141    }
142    // validate parameters
143    if (!audio_is_valid_format(format)) {
144        ALOGE("Invalid format");
145        return BAD_VALUE;
146    }
147
148    if (!audio_is_input_channel(channelMask)) {
149        return BAD_VALUE;
150    }
151
152    int channelCount = popcount(channelMask);
153
154    if (sessionId == 0 ) {
155        mSessionId = AudioSystem::newAudioSessionId();
156    } else {
157        mSessionId = sessionId;
158    }
159    ALOGV("set(): mSessionId %d", mSessionId);
160
161    audio_io_handle_t input = AudioSystem::getInput(inputSource,
162                                                    sampleRate,
163                                                    format,
164                                                    channelMask,
165                                                    (audio_in_acoustics_t) 0,
166                                                    mSessionId);
167    if (input == 0) {
168        ALOGE("Could not get audio input for record source %d", inputSource);
169        return BAD_VALUE;
170    }
171
172    // validate framecount
173    int minFrameCount = 0;
174    status_t status = getMinFrameCount(&minFrameCount, sampleRate, format, channelCount);
175    if (status != NO_ERROR) {
176        return status;
177    }
178    ALOGV("AudioRecord::set() minFrameCount = %d", minFrameCount);
179
180    if (frameCount == 0) {
181        frameCount = minFrameCount;
182    } else if (frameCount < minFrameCount) {
183        return BAD_VALUE;
184    }
185
186    if (notificationFrames == 0) {
187        notificationFrames = frameCount/2;
188    }
189
190    // create the IAudioRecord
191    status = openRecord_l(sampleRate, format, channelMask,
192                        frameCount, input);
193    if (status != NO_ERROR) {
194        return status;
195    }
196
197    if (cbf != NULL) {
198        mClientRecordThread = new ClientRecordThread(*this, threadCanCallJava);
199    }
200
201    mStatus = NO_ERROR;
202
203    mFormat = format;
204    // Update buffer size in case it has been limited by AudioFlinger during track creation
205    mFrameCount = mCblk->frameCount;
206    mChannelCount = (uint8_t)channelCount;
207    mChannelMask = channelMask;
208    mActive = 0;
209    mCbf = cbf;
210    mNotificationFrames = notificationFrames;
211    mRemainingFrames = notificationFrames;
212    mUserData = user;
213    // TODO: add audio hardware input latency here
214    mLatency = (1000*mFrameCount) / sampleRate;
215    mMarkerPosition = 0;
216    mMarkerReached = false;
217    mNewPosition = 0;
218    mUpdatePeriod = 0;
219    mInputSource = inputSource;
220    mInput = input;
221    AudioSystem::acquireAudioSessionId(mSessionId);
222
223    return NO_ERROR;
224}
225
226status_t AudioRecord::initCheck() const
227{
228    return mStatus;
229}
230
231// -------------------------------------------------------------------------
232
233uint32_t AudioRecord::latency() const
234{
235    return mLatency;
236}
237
238audio_format_t AudioRecord::format() const
239{
240    return mFormat;
241}
242
243int AudioRecord::channelCount() const
244{
245    return mChannelCount;
246}
247
248uint32_t AudioRecord::frameCount() const
249{
250    return mFrameCount;
251}
252
253size_t AudioRecord::frameSize() const
254{
255    if (audio_is_linear_pcm(mFormat)) {
256        return channelCount()*audio_bytes_per_sample(mFormat);
257    } else {
258        return sizeof(uint8_t);
259    }
260}
261
262audio_source_t AudioRecord::inputSource() const
263{
264    return mInputSource;
265}
266
267// -------------------------------------------------------------------------
268
269status_t AudioRecord::start(AudioSystem::sync_event_t event, int triggerSession)
270{
271    status_t ret = NO_ERROR;
272    sp<ClientRecordThread> t = mClientRecordThread;
273
274    ALOGV("start, sync event %d trigger session %d", event, triggerSession);
275
276    if (t != 0) {
277        if (t->exitPending()) {
278            if (t->requestExitAndWait() == WOULD_BLOCK) {
279                ALOGE("AudioRecord::start called from thread");
280                return WOULD_BLOCK;
281            }
282        }
283    }
284
285    AutoMutex lock(mLock);
286    // acquire a strong reference on the IAudioRecord and IMemory so that they cannot be destroyed
287    // while we are accessing the cblk
288    sp<IAudioRecord> audioRecord = mAudioRecord;
289    sp<IMemory> iMem = mCblkMemory;
290    audio_track_cblk_t* cblk = mCblk;
291    if (mActive == 0) {
292        mActive = 1;
293
294        pid_t tid;
295        if (t != 0) {
296            mReadyToRun = WOULD_BLOCK;
297            t->run("AudioRecord", ANDROID_PRIORITY_AUDIO);
298            tid = t->getTid();  // pid_t is unknown until run()
299            ALOGV("getTid=%d", tid);
300            if (tid == -1) {
301                tid = 0;
302            }
303            // thread blocks in readyToRun()
304        } else {
305            tid = 0;    // not gettid()
306        }
307
308        cblk->lock.lock();
309        if (!(cblk->flags & CBLK_INVALID_MSK)) {
310            cblk->lock.unlock();
311            ALOGV("mAudioRecord->start()");
312            ret = mAudioRecord->start(event, triggerSession);
313            cblk->lock.lock();
314            if (ret == DEAD_OBJECT) {
315                android_atomic_or(CBLK_INVALID_ON, &cblk->flags);
316            }
317        }
318        if (cblk->flags & CBLK_INVALID_MSK) {
319            ret = restoreRecord_l(cblk);
320        }
321        cblk->lock.unlock();
322        if (ret == NO_ERROR) {
323            mNewPosition = cblk->user + mUpdatePeriod;
324            cblk->bufferTimeoutMs = (event == AudioSystem::SYNC_EVENT_NONE) ? MAX_RUN_TIMEOUT_MS :
325                                            AudioSystem::kSyncRecordStartTimeOutMs;
326            cblk->waitTimeMs = 0;
327            if (t != 0) {
328                // thread unblocks in readyToRun() and returns NO_ERROR
329                mReadyToRun = NO_ERROR;
330                mCondition.signal();
331            } else {
332                mPreviousPriority = getpriority(PRIO_PROCESS, 0);
333                get_sched_policy(0, &mPreviousSchedulingGroup);
334                androidSetThreadPriority(0, ANDROID_PRIORITY_AUDIO);
335            }
336        } else {
337            mActive = 0;
338            // thread unblocks in readyToRun() and returns NO_INIT
339            mReadyToRun = NO_INIT;
340            mCondition.signal();
341        }
342    }
343
344    return ret;
345}
346
347status_t AudioRecord::stop()
348{
349    sp<ClientRecordThread> t = mClientRecordThread;
350
351    ALOGV("stop");
352
353    AutoMutex lock(mLock);
354    if (mActive == 1) {
355        mActive = 0;
356        mCblk->cv.signal();
357        mAudioRecord->stop();
358        // the record head position will reset to 0, so if a marker is set, we need
359        // to activate it again
360        mMarkerReached = false;
361        if (t != 0) {
362            t->requestExit();
363        } else {
364            setpriority(PRIO_PROCESS, 0, mPreviousPriority);
365            set_sched_policy(0, mPreviousSchedulingGroup);
366        }
367    }
368
369    return NO_ERROR;
370}
371
372bool AudioRecord::stopped() const
373{
374    return !mActive;
375}
376
377uint32_t AudioRecord::getSampleRate() const
378{
379    AutoMutex lock(mLock);
380    return mCblk->sampleRate;
381}
382
383status_t AudioRecord::setMarkerPosition(uint32_t marker)
384{
385    if (mCbf == NULL) return INVALID_OPERATION;
386
387    mMarkerPosition = marker;
388    mMarkerReached = false;
389
390    return NO_ERROR;
391}
392
393status_t AudioRecord::getMarkerPosition(uint32_t *marker) const
394{
395    if (marker == NULL) return BAD_VALUE;
396
397    *marker = mMarkerPosition;
398
399    return NO_ERROR;
400}
401
402status_t AudioRecord::setPositionUpdatePeriod(uint32_t updatePeriod)
403{
404    if (mCbf == NULL) return INVALID_OPERATION;
405
406    uint32_t curPosition;
407    getPosition(&curPosition);
408    mNewPosition = curPosition + updatePeriod;
409    mUpdatePeriod = updatePeriod;
410
411    return NO_ERROR;
412}
413
414status_t AudioRecord::getPositionUpdatePeriod(uint32_t *updatePeriod) const
415{
416    if (updatePeriod == NULL) return BAD_VALUE;
417
418    *updatePeriod = mUpdatePeriod;
419
420    return NO_ERROR;
421}
422
423status_t AudioRecord::getPosition(uint32_t *position) const
424{
425    if (position == NULL) return BAD_VALUE;
426
427    AutoMutex lock(mLock);
428    *position = mCblk->user;
429
430    return NO_ERROR;
431}
432
433unsigned int AudioRecord::getInputFramesLost() const
434{
435    if (mActive)
436        return AudioSystem::getInputFramesLost(mInput);
437    else
438        return 0;
439}
440
441// -------------------------------------------------------------------------
442
443// must be called with mLock held
444status_t AudioRecord::openRecord_l(
445        uint32_t sampleRate,
446        audio_format_t format,
447        uint32_t channelMask,
448        int frameCount,
449        audio_io_handle_t input)
450{
451    status_t status;
452    const sp<IAudioFlinger>& audioFlinger = AudioSystem::get_audio_flinger();
453    if (audioFlinger == 0) {
454        return NO_INIT;
455    }
456
457    sp<IAudioRecord> record = audioFlinger->openRecord(getpid(), input,
458                                                       sampleRate, format,
459                                                       channelMask,
460                                                       frameCount,
461                                                       IAudioFlinger::TRACK_DEFAULT,
462                                                       &mSessionId,
463                                                       &status);
464
465    if (record == 0) {
466        ALOGE("AudioFlinger could not create record track, status: %d", status);
467        return status;
468    }
469    sp<IMemory> cblk = record->getCblk();
470    if (cblk == 0) {
471        ALOGE("Could not get control block");
472        return NO_INIT;
473    }
474    mAudioRecord.clear();
475    mAudioRecord = record;
476    mCblkMemory.clear();
477    mCblkMemory = cblk;
478    mCblk = static_cast<audio_track_cblk_t*>(cblk->pointer());
479    mCblk->buffers = (char*)mCblk + sizeof(audio_track_cblk_t);
480    android_atomic_and(~CBLK_DIRECTION_MSK, &mCblk->flags);
481    mCblk->bufferTimeoutMs = MAX_RUN_TIMEOUT_MS;
482    mCblk->waitTimeMs = 0;
483    return NO_ERROR;
484}
485
486status_t AudioRecord::obtainBuffer(Buffer* audioBuffer, int32_t waitCount)
487{
488    AutoMutex lock(mLock);
489    int active;
490    status_t result = NO_ERROR;
491    audio_track_cblk_t* cblk = mCblk;
492    uint32_t framesReq = audioBuffer->frameCount;
493    uint32_t waitTimeMs = (waitCount < 0) ? cblk->bufferTimeoutMs : WAIT_PERIOD_MS;
494
495    audioBuffer->frameCount  = 0;
496    audioBuffer->size        = 0;
497
498    uint32_t framesReady = cblk->framesReady();
499
500    if (framesReady == 0) {
501        cblk->lock.lock();
502        goto start_loop_here;
503        while (framesReady == 0) {
504            active = mActive;
505            if (CC_UNLIKELY(!active)) {
506                cblk->lock.unlock();
507                return NO_MORE_BUFFERS;
508            }
509            if (CC_UNLIKELY(!waitCount)) {
510                cblk->lock.unlock();
511                return WOULD_BLOCK;
512            }
513            if (!(cblk->flags & CBLK_INVALID_MSK)) {
514                mLock.unlock();
515                result = cblk->cv.waitRelative(cblk->lock, milliseconds(waitTimeMs));
516                cblk->lock.unlock();
517                mLock.lock();
518                if (mActive == 0) {
519                    return status_t(STOPPED);
520                }
521                cblk->lock.lock();
522            }
523            if (cblk->flags & CBLK_INVALID_MSK) {
524                goto create_new_record;
525            }
526            if (CC_UNLIKELY(result != NO_ERROR)) {
527                cblk->waitTimeMs += waitTimeMs;
528                if (cblk->waitTimeMs >= cblk->bufferTimeoutMs) {
529                    ALOGW(   "obtainBuffer timed out (is the CPU pegged?) "
530                            "user=%08x, server=%08x", cblk->user, cblk->server);
531                    cblk->lock.unlock();
532                    // callback thread or sync event hasn't changed
533                    result = mAudioRecord->start(AudioSystem::SYNC_EVENT_SAME, 0);
534                    cblk->lock.lock();
535                    if (result == DEAD_OBJECT) {
536                        android_atomic_or(CBLK_INVALID_ON, &cblk->flags);
537create_new_record:
538                        result = AudioRecord::restoreRecord_l(cblk);
539                    }
540                    if (result != NO_ERROR) {
541                        ALOGW("obtainBuffer create Track error %d", result);
542                        cblk->lock.unlock();
543                        return result;
544                    }
545                    cblk->waitTimeMs = 0;
546                }
547                if (--waitCount == 0) {
548                    cblk->lock.unlock();
549                    return TIMED_OUT;
550                }
551            }
552            // read the server count again
553        start_loop_here:
554            framesReady = cblk->framesReady();
555        }
556        cblk->lock.unlock();
557    }
558
559    cblk->waitTimeMs = 0;
560    // reset time out to running value after obtaining a buffer
561    cblk->bufferTimeoutMs = MAX_RUN_TIMEOUT_MS;
562
563    if (framesReq > framesReady) {
564        framesReq = framesReady;
565    }
566
567    uint32_t u = cblk->user;
568    uint32_t bufferEnd = cblk->userBase + cblk->frameCount;
569
570    if (framesReq > bufferEnd - u) {
571        framesReq = bufferEnd - u;
572    }
573
574    audioBuffer->flags       = 0;
575    audioBuffer->channelCount= mChannelCount;
576    audioBuffer->format      = mFormat;
577    audioBuffer->frameCount  = framesReq;
578    audioBuffer->size        = framesReq*cblk->frameSize;
579    audioBuffer->raw         = (int8_t*)cblk->buffer(u);
580    active = mActive;
581    return active ? status_t(NO_ERROR) : status_t(STOPPED);
582}
583
584void AudioRecord::releaseBuffer(Buffer* audioBuffer)
585{
586    AutoMutex lock(mLock);
587    mCblk->stepUser(audioBuffer->frameCount);
588}
589
590audio_io_handle_t AudioRecord::getInput() const
591{
592    AutoMutex lock(mLock);
593    return mInput;
594}
595
596// must be called with mLock held
597audio_io_handle_t AudioRecord::getInput_l()
598{
599    mInput = AudioSystem::getInput(mInputSource,
600                                mCblk->sampleRate,
601                                mFormat,
602                                mChannelMask,
603                                (audio_in_acoustics_t) 0,
604                                mSessionId);
605    return mInput;
606}
607
608int AudioRecord::getSessionId() const
609{
610    return mSessionId;
611}
612
613// -------------------------------------------------------------------------
614
615ssize_t AudioRecord::read(void* buffer, size_t userSize)
616{
617    ssize_t read = 0;
618    Buffer audioBuffer;
619    int8_t *dst = static_cast<int8_t*>(buffer);
620
621    if (ssize_t(userSize) < 0) {
622        // sanity-check. user is most-likely passing an error code.
623        ALOGE("AudioRecord::read(buffer=%p, size=%u (%d)",
624                buffer, userSize, userSize);
625        return BAD_VALUE;
626    }
627
628    mLock.lock();
629    // acquire a strong reference on the IAudioRecord and IMemory so that they cannot be destroyed
630    // while we are accessing the cblk
631    sp<IAudioRecord> audioRecord = mAudioRecord;
632    sp<IMemory> iMem = mCblkMemory;
633    mLock.unlock();
634
635    do {
636
637        audioBuffer.frameCount = userSize/frameSize();
638
639        // By using a wait count corresponding to twice the timeout period in
640        // obtainBuffer() we give a chance to recover once for a read timeout
641        // (if media_server crashed for instance) before returning a length of
642        // 0 bytes read to the client
643        status_t err = obtainBuffer(&audioBuffer, ((2 * MAX_RUN_TIMEOUT_MS) / WAIT_PERIOD_MS));
644        if (err < 0) {
645            // out of buffers, return #bytes written
646            if (err == status_t(NO_MORE_BUFFERS))
647                break;
648            if (err == status_t(TIMED_OUT))
649                err = 0;
650            return ssize_t(err);
651        }
652
653        size_t bytesRead = audioBuffer.size;
654        memcpy(dst, audioBuffer.i8, bytesRead);
655
656        dst += bytesRead;
657        userSize -= bytesRead;
658        read += bytesRead;
659
660        releaseBuffer(&audioBuffer);
661    } while (userSize);
662
663    return read;
664}
665
666// -------------------------------------------------------------------------
667
668bool AudioRecord::processAudioBuffer(const sp<ClientRecordThread>& thread)
669{
670    Buffer audioBuffer;
671    uint32_t frames = mRemainingFrames;
672    size_t readSize;
673
674    mLock.lock();
675    // acquire a strong reference on the IAudioRecord and IMemory so that they cannot be destroyed
676    // while we are accessing the cblk
677    sp<IAudioRecord> audioRecord = mAudioRecord;
678    sp<IMemory> iMem = mCblkMemory;
679    audio_track_cblk_t* cblk = mCblk;
680    mLock.unlock();
681
682    // Manage marker callback
683    if (!mMarkerReached && (mMarkerPosition > 0)) {
684        if (cblk->user >= mMarkerPosition) {
685            mCbf(EVENT_MARKER, mUserData, (void *)&mMarkerPosition);
686            mMarkerReached = true;
687        }
688    }
689
690    // Manage new position callback
691    if (mUpdatePeriod > 0) {
692        while (cblk->user >= mNewPosition) {
693            mCbf(EVENT_NEW_POS, mUserData, (void *)&mNewPosition);
694            mNewPosition += mUpdatePeriod;
695        }
696    }
697
698    do {
699        audioBuffer.frameCount = frames;
700        // Calling obtainBuffer() with a wait count of 1
701        // limits wait time to WAIT_PERIOD_MS. This prevents from being
702        // stuck here not being able to handle timed events (position, markers).
703        status_t err = obtainBuffer(&audioBuffer, 1);
704        if (err < NO_ERROR) {
705            if (err != TIMED_OUT) {
706                ALOGE_IF(err != status_t(NO_MORE_BUFFERS), "Error obtaining an audio buffer, giving up.");
707                return false;
708            }
709            break;
710        }
711        if (err == status_t(STOPPED)) return false;
712
713        size_t reqSize = audioBuffer.size;
714        mCbf(EVENT_MORE_DATA, mUserData, &audioBuffer);
715        readSize = audioBuffer.size;
716
717        // Sanity check on returned size
718        if (ssize_t(readSize) <= 0) {
719            // The callback is done filling buffers
720            // Keep this thread going to handle timed events and
721            // still try to get more data in intervals of WAIT_PERIOD_MS
722            // but don't just loop and block the CPU, so wait
723            usleep(WAIT_PERIOD_MS*1000);
724            break;
725        }
726        if (readSize > reqSize) readSize = reqSize;
727
728        audioBuffer.size = readSize;
729        audioBuffer.frameCount = readSize/frameSize();
730        frames -= audioBuffer.frameCount;
731
732        releaseBuffer(&audioBuffer);
733
734    } while (frames);
735
736
737    // Manage overrun callback
738    if (mActive && (cblk->framesAvailable() == 0)) {
739        ALOGV("Overrun user: %x, server: %x, flags %04x", cblk->user, cblk->server, cblk->flags);
740        if (!(android_atomic_or(CBLK_UNDERRUN_ON, &cblk->flags) & CBLK_UNDERRUN_MSK)) {
741            mCbf(EVENT_OVERRUN, mUserData, 0);
742        }
743    }
744
745    if (frames == 0) {
746        mRemainingFrames = mNotificationFrames;
747    } else {
748        mRemainingFrames = frames;
749    }
750    return true;
751}
752
753// must be called with mLock and cblk.lock held. Callers must also hold strong references on
754// the IAudioRecord and IMemory in case they are recreated here.
755// If the IAudioRecord is successfully restored, the cblk pointer is updated
756status_t AudioRecord::restoreRecord_l(audio_track_cblk_t*& cblk)
757{
758    status_t result;
759
760    if (!(android_atomic_or(CBLK_RESTORING_ON, &cblk->flags) & CBLK_RESTORING_MSK)) {
761        ALOGW("dead IAudioRecord, creating a new one");
762        // signal old cblk condition so that other threads waiting for available buffers stop
763        // waiting now
764        cblk->cv.broadcast();
765        cblk->lock.unlock();
766
767        // if the new IAudioRecord is created, openRecord_l() will modify the
768        // following member variables: mAudioRecord, mCblkMemory and mCblk.
769        // It will also delete the strong references on previous IAudioRecord and IMemory
770        result = openRecord_l(cblk->sampleRate, mFormat, mChannelMask,
771                mFrameCount, getInput_l());
772        if (result == NO_ERROR) {
773            // callback thread or sync event hasn't changed
774            result = mAudioRecord->start(AudioSystem::SYNC_EVENT_SAME, 0);
775        }
776        if (result != NO_ERROR) {
777            mActive = false;
778        }
779
780        // signal old cblk condition for other threads waiting for restore completion
781        android_atomic_or(CBLK_RESTORED_ON, &cblk->flags);
782        cblk->cv.broadcast();
783    } else {
784        if (!(cblk->flags & CBLK_RESTORED_MSK)) {
785            ALOGW("dead IAudioRecord, waiting for a new one to be created");
786            mLock.unlock();
787            result = cblk->cv.waitRelative(cblk->lock, milliseconds(RESTORE_TIMEOUT_MS));
788            cblk->lock.unlock();
789            mLock.lock();
790        } else {
791            ALOGW("dead IAudioRecord, already restored");
792            result = NO_ERROR;
793            cblk->lock.unlock();
794        }
795        if (result != NO_ERROR || mActive == 0) {
796            result = status_t(STOPPED);
797        }
798    }
799    ALOGV("restoreRecord_l() status %d mActive %d cblk %p, old cblk %p flags %08x old flags %08x",
800        result, mActive, mCblk, cblk, mCblk->flags, cblk->flags);
801
802    if (result == NO_ERROR) {
803        // from now on we switch to the newly created cblk
804        cblk = mCblk;
805    }
806    cblk->lock.lock();
807
808    ALOGW_IF(result != NO_ERROR, "restoreRecord_l() error %d", result);
809
810    return result;
811}
812
813// =========================================================================
814
815AudioRecord::ClientRecordThread::ClientRecordThread(AudioRecord& receiver, bool bCanCallJava)
816    : Thread(bCanCallJava), mReceiver(receiver)
817{
818}
819
820bool AudioRecord::ClientRecordThread::threadLoop()
821{
822    return mReceiver.processAudioBuffer(this);
823}
824
825status_t AudioRecord::ClientRecordThread::readyToRun()
826{
827    AutoMutex(mReceiver.mLock);
828    while (mReceiver.mReadyToRun == WOULD_BLOCK) {
829        mReceiver.mCondition.wait(mReceiver.mLock);
830    }
831    return mReceiver.mReadyToRun;
832}
833
834// -------------------------------------------------------------------------
835
836}; // namespace android
837