AudioTrack.cpp revision b9980659501d0428d65d8292f3c32da69d37fbd2
1/* frameworks/base/media/libmedia/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 <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 46namespace android { 47// --------------------------------------------------------------------------- 48 49// static 50status_t AudioTrack::getMinFrameCount( 51 int* frameCount, 52 int streamType, 53 uint32_t sampleRate) 54{ 55 int afSampleRate; 56 if (AudioSystem::getOutputSamplingRate(&afSampleRate, streamType) != NO_ERROR) { 57 return NO_INIT; 58 } 59 int afFrameCount; 60 if (AudioSystem::getOutputFrameCount(&afFrameCount, streamType) != NO_ERROR) { 61 return NO_INIT; 62 } 63 uint32_t afLatency; 64 if (AudioSystem::getOutputLatency(&afLatency, streamType) != NO_ERROR) { 65 return NO_INIT; 66 } 67 68 // Ensure that buffer depth covers at least audio hardware latency 69 uint32_t minBufCount = afLatency / ((1000 * afFrameCount) / afSampleRate); 70 if (minBufCount < 2) minBufCount = 2; 71 72 *frameCount = (sampleRate == 0) ? afFrameCount * minBufCount : 73 afFrameCount * minBufCount * sampleRate / afSampleRate; 74 return NO_ERROR; 75} 76 77// --------------------------------------------------------------------------- 78 79AudioTrack::AudioTrack() 80 : mStatus(NO_INIT), 81 mPreviousPriority(ANDROID_PRIORITY_NORMAL), mPreviousSchedulingGroup(ANDROID_TGROUP_DEFAULT) 82{ 83} 84 85AudioTrack::AudioTrack( 86 int streamType, 87 uint32_t sampleRate, 88 audio_format_t format, 89 int channelMask, 90 int frameCount, 91 uint32_t flags, 92 callback_t cbf, 93 void* user, 94 int notificationFrames, 95 int sessionId) 96 : mStatus(NO_INIT), 97 mPreviousPriority(ANDROID_PRIORITY_NORMAL), mPreviousSchedulingGroup(ANDROID_TGROUP_DEFAULT) 98{ 99 mStatus = set(streamType, sampleRate, format, channelMask, 100 frameCount, flags, cbf, user, notificationFrames, 101 0, false, sessionId); 102} 103 104AudioTrack::AudioTrack( 105 int streamType, 106 uint32_t sampleRate, 107 audio_format_t format, 108 int channelMask, 109 const sp<IMemory>& sharedBuffer, 110 uint32_t flags, 111 callback_t cbf, 112 void* user, 113 int notificationFrames, 114 int sessionId) 115 : mStatus(NO_INIT), 116 mPreviousPriority(ANDROID_PRIORITY_NORMAL), mPreviousSchedulingGroup(ANDROID_TGROUP_DEFAULT) 117{ 118 mStatus = set(streamType, sampleRate, format, channelMask, 119 0, flags, cbf, user, notificationFrames, 120 sharedBuffer, false, sessionId); 121} 122 123AudioTrack::~AudioTrack() 124{ 125 ALOGV_IF(mSharedBuffer != 0, "Destructor sharedBuffer: %p", mSharedBuffer->pointer()); 126 127 if (mStatus == NO_ERROR) { 128 // Make sure that callback function exits in the case where 129 // it is looping on buffer full condition in obtainBuffer(). 130 // Otherwise the callback thread will never exit. 131 stop(); 132 if (mAudioTrackThread != 0) { 133 mAudioTrackThread->requestExitAndWait(); 134 mAudioTrackThread.clear(); 135 } 136 mAudioTrack.clear(); 137 IPCThreadState::self()->flushCommands(); 138 AudioSystem::releaseAudioSessionId(mSessionId); 139 } 140} 141 142status_t AudioTrack::set( 143 int streamType, 144 uint32_t sampleRate, 145 audio_format_t format, 146 int channelMask, 147 int frameCount, 148 uint32_t flags, 149 callback_t cbf, 150 void* user, 151 int notificationFrames, 152 const sp<IMemory>& sharedBuffer, 153 bool threadCanCallJava, 154 int sessionId) 155{ 156 157 ALOGV_IF(sharedBuffer != 0, "sharedBuffer: %p, size: %d", sharedBuffer->pointer(), sharedBuffer->size()); 158 159 AutoMutex lock(mLock); 160 if (mAudioTrack != 0) { 161 ALOGE("Track already in use"); 162 return INVALID_OPERATION; 163 } 164 165 int afSampleRate; 166 if (AudioSystem::getOutputSamplingRate(&afSampleRate, streamType) != NO_ERROR) { 167 return NO_INIT; 168 } 169 uint32_t afLatency; 170 if (AudioSystem::getOutputLatency(&afLatency, streamType) != NO_ERROR) { 171 return NO_INIT; 172 } 173 174 // handle default values first. 175 if (streamType == AUDIO_STREAM_DEFAULT) { 176 streamType = AUDIO_STREAM_MUSIC; 177 } 178 if (sampleRate == 0) { 179 sampleRate = afSampleRate; 180 } 181 // these below should probably come from the audioFlinger too... 182 if (format == AUDIO_FORMAT_DEFAULT) { 183 format = AUDIO_FORMAT_PCM_16_BIT; 184 } 185 if (channelMask == 0) { 186 channelMask = AUDIO_CHANNEL_OUT_STEREO; 187 } 188 189 // validate parameters 190 if (!audio_is_valid_format(format)) { 191 ALOGE("Invalid format"); 192 return BAD_VALUE; 193 } 194 195 // force direct flag if format is not linear PCM 196 if (!audio_is_linear_pcm(format)) { 197 flags |= AUDIO_POLICY_OUTPUT_FLAG_DIRECT; 198 } 199 200 if (!audio_is_output_channel(channelMask)) { 201 ALOGE("Invalid channel mask"); 202 return BAD_VALUE; 203 } 204 uint32_t channelCount = popcount(channelMask); 205 206 audio_io_handle_t output = AudioSystem::getOutput( 207 (audio_stream_type_t)streamType, 208 sampleRate, format, channelMask, 209 (audio_policy_output_flags_t)flags); 210 211 if (output == 0) { 212 ALOGE("Could not get audio output for stream type %d", streamType); 213 return BAD_VALUE; 214 } 215 216 mVolume[LEFT] = 1.0f; 217 mVolume[RIGHT] = 1.0f; 218 mSendLevel = 0; 219 mFrameCount = frameCount; 220 mNotificationFramesReq = notificationFrames; 221 mSessionId = sessionId; 222 mAuxEffectId = 0; 223 224 // create the IAudioTrack 225 status_t status = createTrack_l(streamType, 226 sampleRate, 227 format, 228 (uint32_t)channelMask, 229 frameCount, 230 flags, 231 sharedBuffer, 232 output, 233 true); 234 235 if (status != NO_ERROR) { 236 return status; 237 } 238 239 if (cbf != 0) { 240 mAudioTrackThread = new AudioTrackThread(*this, threadCanCallJava); 241 } 242 243 mStatus = NO_ERROR; 244 245 mStreamType = streamType; 246 mFormat = format; 247 mChannelMask = (uint32_t)channelMask; 248 mChannelCount = channelCount; 249 mSharedBuffer = sharedBuffer; 250 mMuted = false; 251 mActive = false; 252 mCbf = cbf; 253 mUserData = user; 254 mLoopCount = 0; 255 mMarkerPosition = 0; 256 mMarkerReached = false; 257 mNewPosition = 0; 258 mUpdatePeriod = 0; 259 mFlushed = false; 260 mFlags = flags; 261 AudioSystem::acquireAudioSessionId(mSessionId); 262 mRestoreStatus = NO_ERROR; 263 return NO_ERROR; 264} 265 266status_t AudioTrack::initCheck() const 267{ 268 return mStatus; 269} 270 271// ------------------------------------------------------------------------- 272 273uint32_t AudioTrack::latency() const 274{ 275 return mLatency; 276} 277 278int AudioTrack::streamType() const 279{ 280 return mStreamType; 281} 282 283audio_format_t AudioTrack::format() const 284{ 285 return mFormat; 286} 287 288int AudioTrack::channelCount() const 289{ 290 return mChannelCount; 291} 292 293uint32_t AudioTrack::frameCount() const 294{ 295 return mCblk->frameCount; 296} 297 298size_t AudioTrack::frameSize() const 299{ 300 if (audio_is_linear_pcm(mFormat)) { 301 return channelCount()*audio_bytes_per_sample(mFormat); 302 } else { 303 return sizeof(uint8_t); 304 } 305} 306 307sp<IMemory>& AudioTrack::sharedBuffer() 308{ 309 return mSharedBuffer; 310} 311 312// ------------------------------------------------------------------------- 313 314void AudioTrack::start() 315{ 316 sp<AudioTrackThread> t = mAudioTrackThread; 317 status_t status = NO_ERROR; 318 319 ALOGV("start %p", this); 320 if (t != 0) { 321 if (t->exitPending()) { 322 if (t->requestExitAndWait() == WOULD_BLOCK) { 323 ALOGE("AudioTrack::start called from thread"); 324 return; 325 } 326 } 327 t->mLock.lock(); 328 } 329 330 AutoMutex lock(mLock); 331 // acquire a strong reference on the IMemory and IAudioTrack so that they cannot be destroyed 332 // while we are accessing the cblk 333 sp <IAudioTrack> audioTrack = mAudioTrack; 334 sp <IMemory> iMem = mCblkMemory; 335 audio_track_cblk_t* cblk = mCblk; 336 337 if (!mActive) { 338 mFlushed = false; 339 mActive = true; 340 mNewPosition = cblk->server + mUpdatePeriod; 341 cblk->lock.lock(); 342 cblk->bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS; 343 cblk->waitTimeMs = 0; 344 android_atomic_and(~CBLK_DISABLED_ON, &cblk->flags); 345 if (t != 0) { 346 t->run("AudioTrackThread", ANDROID_PRIORITY_AUDIO); 347 } else { 348 mPreviousPriority = getpriority(PRIO_PROCESS, 0); 349 mPreviousSchedulingGroup = androidGetThreadSchedulingGroup(0); 350 androidSetThreadPriority(0, ANDROID_PRIORITY_AUDIO); 351 } 352 353 ALOGV("start %p before lock cblk %p", this, mCblk); 354 if (!(cblk->flags & CBLK_INVALID_MSK)) { 355 cblk->lock.unlock(); 356 status = mAudioTrack->start(); 357 cblk->lock.lock(); 358 if (status == DEAD_OBJECT) { 359 android_atomic_or(CBLK_INVALID_ON, &cblk->flags); 360 } 361 } 362 if (cblk->flags & CBLK_INVALID_MSK) { 363 status = restoreTrack_l(cblk, true); 364 } 365 cblk->lock.unlock(); 366 if (status != NO_ERROR) { 367 ALOGV("start() failed"); 368 mActive = false; 369 if (t != 0) { 370 t->requestExit(); 371 } else { 372 setpriority(PRIO_PROCESS, 0, mPreviousPriority); 373 androidSetThreadSchedulingGroup(0, mPreviousSchedulingGroup); 374 } 375 } 376 } 377 378 if (t != 0) { 379 t->mLock.unlock(); 380 } 381} 382 383void AudioTrack::stop() 384{ 385 sp<AudioTrackThread> t = mAudioTrackThread; 386 387 ALOGV("stop %p", this); 388 if (t != 0) { 389 t->mLock.lock(); 390 } 391 392 AutoMutex lock(mLock); 393 if (mActive) { 394 mActive = false; 395 mCblk->cv.signal(); 396 mAudioTrack->stop(); 397 // Cancel loops (If we are in the middle of a loop, playback 398 // would not stop until loopCount reaches 0). 399 setLoop_l(0, 0, 0); 400 // the playback head position will reset to 0, so if a marker is set, we need 401 // to activate it again 402 mMarkerReached = false; 403 // Force flush if a shared buffer is used otherwise audioflinger 404 // will not stop before end of buffer is reached. 405 if (mSharedBuffer != 0) { 406 flush_l(); 407 } 408 if (t != 0) { 409 t->requestExit(); 410 } else { 411 setpriority(PRIO_PROCESS, 0, mPreviousPriority); 412 androidSetThreadSchedulingGroup(0, mPreviousSchedulingGroup); 413 } 414 } 415 416 if (t != 0) { 417 t->mLock.unlock(); 418 } 419} 420 421bool AudioTrack::stopped() const 422{ 423 AutoMutex lock(mLock); 424 return stopped_l(); 425} 426 427void AudioTrack::flush() 428{ 429 AutoMutex lock(mLock); 430 flush_l(); 431} 432 433// must be called with mLock held 434void AudioTrack::flush_l() 435{ 436 ALOGV("flush"); 437 438 // clear playback marker and periodic update counter 439 mMarkerPosition = 0; 440 mMarkerReached = false; 441 mUpdatePeriod = 0; 442 443 if (!mActive) { 444 mFlushed = true; 445 mAudioTrack->flush(); 446 // Release AudioTrack callback thread in case it was waiting for new buffers 447 // in AudioTrack::obtainBuffer() 448 mCblk->cv.signal(); 449 } 450} 451 452void AudioTrack::pause() 453{ 454 ALOGV("pause"); 455 AutoMutex lock(mLock); 456 if (mActive) { 457 mActive = false; 458 mAudioTrack->pause(); 459 } 460} 461 462void AudioTrack::mute(bool e) 463{ 464 mAudioTrack->mute(e); 465 mMuted = e; 466} 467 468bool AudioTrack::muted() const 469{ 470 return mMuted; 471} 472 473status_t AudioTrack::setVolume(float left, float right) 474{ 475 if (left < 0.0f || left > 1.0f || right < 0.0f || right > 1.0f) { 476 return BAD_VALUE; 477 } 478 479 AutoMutex lock(mLock); 480 mVolume[LEFT] = left; 481 mVolume[RIGHT] = right; 482 483 // write must be atomic 484 mCblk->volumeLR = (uint32_t(uint16_t(right * 0x1000)) << 16) | uint16_t(left * 0x1000); 485 486 return NO_ERROR; 487} 488 489void AudioTrack::getVolume(float* left, float* right) 490{ 491 if (left != NULL) { 492 *left = mVolume[LEFT]; 493 } 494 if (right != NULL) { 495 *right = mVolume[RIGHT]; 496 } 497} 498 499status_t AudioTrack::setAuxEffectSendLevel(float level) 500{ 501 ALOGV("setAuxEffectSendLevel(%f)", level); 502 if (level > 1.0f) { 503 return BAD_VALUE; 504 } 505 AutoMutex lock(mLock); 506 507 mSendLevel = level; 508 509 mCblk->sendLevel = uint16_t(level * 0x1000); 510 511 return NO_ERROR; 512} 513 514void AudioTrack::getAuxEffectSendLevel(float* level) 515{ 516 if (level != NULL) { 517 *level = mSendLevel; 518 } 519} 520 521status_t AudioTrack::setSampleRate(int rate) 522{ 523 int afSamplingRate; 524 525 if (AudioSystem::getOutputSamplingRate(&afSamplingRate, mStreamType) != NO_ERROR) { 526 return NO_INIT; 527 } 528 // Resampler implementation limits input sampling rate to 2 x output sampling rate. 529 if (rate <= 0 || rate > afSamplingRate*2 ) return BAD_VALUE; 530 531 AutoMutex lock(mLock); 532 mCblk->sampleRate = rate; 533 return NO_ERROR; 534} 535 536uint32_t AudioTrack::getSampleRate() 537{ 538 AutoMutex lock(mLock); 539 return mCblk->sampleRate; 540} 541 542status_t AudioTrack::setLoop(uint32_t loopStart, uint32_t loopEnd, int loopCount) 543{ 544 AutoMutex lock(mLock); 545 return setLoop_l(loopStart, loopEnd, loopCount); 546} 547 548// must be called with mLock held 549status_t AudioTrack::setLoop_l(uint32_t loopStart, uint32_t loopEnd, int loopCount) 550{ 551 audio_track_cblk_t* cblk = mCblk; 552 553 Mutex::Autolock _l(cblk->lock); 554 555 if (loopCount == 0) { 556 cblk->loopStart = UINT_MAX; 557 cblk->loopEnd = UINT_MAX; 558 cblk->loopCount = 0; 559 mLoopCount = 0; 560 return NO_ERROR; 561 } 562 563 if (loopStart >= loopEnd || 564 loopEnd - loopStart > cblk->frameCount || 565 cblk->server > loopStart) { 566 ALOGE("setLoop invalid value: loopStart %d, loopEnd %d, loopCount %d, framecount %d, user %d", loopStart, loopEnd, loopCount, cblk->frameCount, cblk->user); 567 return BAD_VALUE; 568 } 569 570 if ((mSharedBuffer != 0) && (loopEnd > cblk->frameCount)) { 571 ALOGE("setLoop invalid value: loop markers beyond data: loopStart %d, loopEnd %d, framecount %d", 572 loopStart, loopEnd, cblk->frameCount); 573 return BAD_VALUE; 574 } 575 576 cblk->loopStart = loopStart; 577 cblk->loopEnd = loopEnd; 578 cblk->loopCount = loopCount; 579 mLoopCount = loopCount; 580 581 return NO_ERROR; 582} 583 584status_t AudioTrack::getLoop(uint32_t *loopStart, uint32_t *loopEnd, int *loopCount) 585{ 586 AutoMutex lock(mLock); 587 if (loopStart != 0) { 588 *loopStart = mCblk->loopStart; 589 } 590 if (loopEnd != 0) { 591 *loopEnd = mCblk->loopEnd; 592 } 593 if (loopCount != 0) { 594 if (mCblk->loopCount < 0) { 595 *loopCount = -1; 596 } else { 597 *loopCount = mCblk->loopCount; 598 } 599 } 600 601 return NO_ERROR; 602} 603 604status_t AudioTrack::setMarkerPosition(uint32_t marker) 605{ 606 if (mCbf == 0) return INVALID_OPERATION; 607 608 mMarkerPosition = marker; 609 mMarkerReached = false; 610 611 return NO_ERROR; 612} 613 614status_t AudioTrack::getMarkerPosition(uint32_t *marker) 615{ 616 if (marker == 0) return BAD_VALUE; 617 618 *marker = mMarkerPosition; 619 620 return NO_ERROR; 621} 622 623status_t AudioTrack::setPositionUpdatePeriod(uint32_t updatePeriod) 624{ 625 if (mCbf == 0) return INVALID_OPERATION; 626 627 uint32_t curPosition; 628 getPosition(&curPosition); 629 mNewPosition = curPosition + updatePeriod; 630 mUpdatePeriod = updatePeriod; 631 632 return NO_ERROR; 633} 634 635status_t AudioTrack::getPositionUpdatePeriod(uint32_t *updatePeriod) 636{ 637 if (updatePeriod == 0) return BAD_VALUE; 638 639 *updatePeriod = mUpdatePeriod; 640 641 return NO_ERROR; 642} 643 644status_t AudioTrack::setPosition(uint32_t position) 645{ 646 AutoMutex lock(mLock); 647 648 if (!stopped_l()) return INVALID_OPERATION; 649 650 Mutex::Autolock _l(mCblk->lock); 651 652 if (position > mCblk->user) return BAD_VALUE; 653 654 mCblk->server = position; 655 android_atomic_or(CBLK_FORCEREADY_ON, &mCblk->flags); 656 657 return NO_ERROR; 658} 659 660status_t AudioTrack::getPosition(uint32_t *position) 661{ 662 if (position == 0) return BAD_VALUE; 663 AutoMutex lock(mLock); 664 *position = mFlushed ? 0 : mCblk->server; 665 666 return NO_ERROR; 667} 668 669status_t AudioTrack::reload() 670{ 671 AutoMutex lock(mLock); 672 673 if (!stopped_l()) return INVALID_OPERATION; 674 675 flush_l(); 676 677 mCblk->stepUser(mCblk->frameCount); 678 679 return NO_ERROR; 680} 681 682audio_io_handle_t AudioTrack::getOutput() 683{ 684 AutoMutex lock(mLock); 685 return getOutput_l(); 686} 687 688// must be called with mLock held 689audio_io_handle_t AudioTrack::getOutput_l() 690{ 691 return AudioSystem::getOutput((audio_stream_type_t)mStreamType, 692 mCblk->sampleRate, mFormat, mChannelMask, (audio_policy_output_flags_t)mFlags); 693} 694 695int AudioTrack::getSessionId() 696{ 697 return mSessionId; 698} 699 700status_t AudioTrack::attachAuxEffect(int effectId) 701{ 702 ALOGV("attachAuxEffect(%d)", effectId); 703 status_t status = mAudioTrack->attachAuxEffect(effectId); 704 if (status == NO_ERROR) { 705 mAuxEffectId = effectId; 706 } 707 return status; 708} 709 710// ------------------------------------------------------------------------- 711 712// must be called with mLock held 713status_t AudioTrack::createTrack_l( 714 int streamType, 715 uint32_t sampleRate, 716 audio_format_t format, 717 uint32_t channelMask, 718 int frameCount, 719 uint32_t flags, 720 const sp<IMemory>& sharedBuffer, 721 audio_io_handle_t output, 722 bool enforceFrameCount) 723{ 724 status_t status; 725 const sp<IAudioFlinger>& audioFlinger = AudioSystem::get_audio_flinger(); 726 if (audioFlinger == 0) { 727 ALOGE("Could not get audioflinger"); 728 return NO_INIT; 729 } 730 731 int afSampleRate; 732 if (AudioSystem::getOutputSamplingRate(&afSampleRate, streamType) != NO_ERROR) { 733 return NO_INIT; 734 } 735 int afFrameCount; 736 if (AudioSystem::getOutputFrameCount(&afFrameCount, streamType) != NO_ERROR) { 737 return NO_INIT; 738 } 739 uint32_t afLatency; 740 if (AudioSystem::getOutputLatency(&afLatency, streamType) != NO_ERROR) { 741 return NO_INIT; 742 } 743 744 mNotificationFramesAct = mNotificationFramesReq; 745 if (!audio_is_linear_pcm(format)) { 746 if (sharedBuffer != 0) { 747 frameCount = sharedBuffer->size(); 748 } 749 } else { 750 // Ensure that buffer depth covers at least audio hardware latency 751 uint32_t minBufCount = afLatency / ((1000 * afFrameCount)/afSampleRate); 752 if (minBufCount < 2) minBufCount = 2; 753 754 int minFrameCount = (afFrameCount*sampleRate*minBufCount)/afSampleRate; 755 756 if (sharedBuffer == 0) { 757 if (frameCount == 0) { 758 frameCount = minFrameCount; 759 } 760 if (mNotificationFramesAct == 0) { 761 mNotificationFramesAct = frameCount/2; 762 } 763 // Make sure that application is notified with sufficient margin 764 // before underrun 765 if (mNotificationFramesAct > (uint32_t)frameCount/2) { 766 mNotificationFramesAct = frameCount/2; 767 } 768 if (frameCount < minFrameCount) { 769 if (enforceFrameCount) { 770 ALOGE("Invalid buffer size: minFrameCount %d, frameCount %d", minFrameCount, frameCount); 771 return BAD_VALUE; 772 } else { 773 frameCount = minFrameCount; 774 } 775 } 776 } else { 777 // Ensure that buffer alignment matches channelcount 778 int channelCount = popcount(channelMask); 779 if (((uint32_t)sharedBuffer->pointer() & (channelCount | 1)) != 0) { 780 ALOGE("Invalid buffer alignement: address %p, channelCount %d", sharedBuffer->pointer(), channelCount); 781 return BAD_VALUE; 782 } 783 frameCount = sharedBuffer->size()/channelCount/sizeof(int16_t); 784 } 785 } 786 787 sp<IAudioTrack> track = audioFlinger->createTrack(getpid(), 788 streamType, 789 sampleRate, 790 format, 791 channelMask, 792 frameCount, 793 ((uint16_t)flags) << 16, 794 sharedBuffer, 795 output, 796 &mSessionId, 797 &status); 798 799 if (track == 0) { 800 ALOGE("AudioFlinger could not create track, status: %d", status); 801 return status; 802 } 803 sp<IMemory> cblk = track->getCblk(); 804 if (cblk == 0) { 805 ALOGE("Could not get control block"); 806 return NO_INIT; 807 } 808 mAudioTrack = track; 809 mCblkMemory = cblk; 810 mCblk = static_cast<audio_track_cblk_t*>(cblk->pointer()); 811 android_atomic_or(CBLK_DIRECTION_OUT, &mCblk->flags); 812 if (sharedBuffer == 0) { 813 mCblk->buffers = (char*)mCblk + sizeof(audio_track_cblk_t); 814 } else { 815 mCblk->buffers = sharedBuffer->pointer(); 816 // Force buffer full condition as data is already present in shared memory 817 mCblk->stepUser(mCblk->frameCount); 818 } 819 820 mCblk->volumeLR = (uint32_t(uint16_t(mVolume[RIGHT] * 0x1000)) << 16) | uint16_t(mVolume[LEFT] * 0x1000); 821 mCblk->sendLevel = uint16_t(mSendLevel * 0x1000); 822 mAudioTrack->attachAuxEffect(mAuxEffectId); 823 mCblk->bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS; 824 mCblk->waitTimeMs = 0; 825 mRemainingFrames = mNotificationFramesAct; 826 mLatency = afLatency + (1000*mCblk->frameCount) / sampleRate; 827 return NO_ERROR; 828} 829 830status_t AudioTrack::obtainBuffer(Buffer* audioBuffer, int32_t waitCount) 831{ 832 AutoMutex lock(mLock); 833 bool active; 834 status_t result = NO_ERROR; 835 audio_track_cblk_t* cblk = mCblk; 836 uint32_t framesReq = audioBuffer->frameCount; 837 uint32_t waitTimeMs = (waitCount < 0) ? cblk->bufferTimeoutMs : WAIT_PERIOD_MS; 838 839 audioBuffer->frameCount = 0; 840 audioBuffer->size = 0; 841 842 uint32_t framesAvail = cblk->framesAvailable(); 843 844 cblk->lock.lock(); 845 if (cblk->flags & CBLK_INVALID_MSK) { 846 goto create_new_track; 847 } 848 cblk->lock.unlock(); 849 850 if (framesAvail == 0) { 851 cblk->lock.lock(); 852 goto start_loop_here; 853 while (framesAvail == 0) { 854 active = mActive; 855 if (CC_UNLIKELY(!active)) { 856 ALOGV("Not active and NO_MORE_BUFFERS"); 857 cblk->lock.unlock(); 858 return NO_MORE_BUFFERS; 859 } 860 if (CC_UNLIKELY(!waitCount)) { 861 cblk->lock.unlock(); 862 return WOULD_BLOCK; 863 } 864 if (!(cblk->flags & CBLK_INVALID_MSK)) { 865 mLock.unlock(); 866 result = cblk->cv.waitRelative(cblk->lock, milliseconds(waitTimeMs)); 867 cblk->lock.unlock(); 868 mLock.lock(); 869 if (!mActive) { 870 return status_t(STOPPED); 871 } 872 cblk->lock.lock(); 873 } 874 875 if (cblk->flags & CBLK_INVALID_MSK) { 876 goto create_new_track; 877 } 878 if (CC_UNLIKELY(result != NO_ERROR)) { 879 cblk->waitTimeMs += waitTimeMs; 880 if (cblk->waitTimeMs >= cblk->bufferTimeoutMs) { 881 // timing out when a loop has been set and we have already written upto loop end 882 // is a normal condition: no need to wake AudioFlinger up. 883 if (cblk->user < cblk->loopEnd) { 884 ALOGW( "obtainBuffer timed out (is the CPU pegged?) %p " 885 "user=%08x, server=%08x", this, cblk->user, cblk->server); 886 //unlock cblk mutex before calling mAudioTrack->start() (see issue #1617140) 887 cblk->lock.unlock(); 888 result = mAudioTrack->start(); 889 cblk->lock.lock(); 890 if (result == DEAD_OBJECT) { 891 android_atomic_or(CBLK_INVALID_ON, &cblk->flags); 892create_new_track: 893 result = restoreTrack_l(cblk, false); 894 } 895 if (result != NO_ERROR) { 896 ALOGW("obtainBuffer create Track error %d", result); 897 cblk->lock.unlock(); 898 return result; 899 } 900 } 901 cblk->waitTimeMs = 0; 902 } 903 904 if (--waitCount == 0) { 905 cblk->lock.unlock(); 906 return TIMED_OUT; 907 } 908 } 909 // read the server count again 910 start_loop_here: 911 framesAvail = cblk->framesAvailable_l(); 912 } 913 cblk->lock.unlock(); 914 } 915 916 // restart track if it was disabled by audioflinger due to previous underrun 917 if (mActive && (cblk->flags & CBLK_DISABLED_MSK)) { 918 android_atomic_and(~CBLK_DISABLED_ON, &cblk->flags); 919 ALOGW("obtainBuffer() track %p disabled, restarting", this); 920 mAudioTrack->start(); 921 } 922 923 cblk->waitTimeMs = 0; 924 925 if (framesReq > framesAvail) { 926 framesReq = framesAvail; 927 } 928 929 uint32_t u = cblk->user; 930 uint32_t bufferEnd = cblk->userBase + cblk->frameCount; 931 932 if (u + framesReq > bufferEnd) { 933 framesReq = bufferEnd - u; 934 } 935 936 audioBuffer->flags = mMuted ? Buffer::MUTE : 0; 937 audioBuffer->channelCount = mChannelCount; 938 audioBuffer->frameCount = framesReq; 939 audioBuffer->size = framesReq * cblk->frameSize; 940 if (audio_is_linear_pcm(mFormat)) { 941 audioBuffer->format = AUDIO_FORMAT_PCM_16_BIT; 942 } else { 943 audioBuffer->format = mFormat; 944 } 945 audioBuffer->raw = (int8_t *)cblk->buffer(u); 946 active = mActive; 947 return active ? status_t(NO_ERROR) : status_t(STOPPED); 948} 949 950void AudioTrack::releaseBuffer(Buffer* audioBuffer) 951{ 952 AutoMutex lock(mLock); 953 mCblk->stepUser(audioBuffer->frameCount); 954} 955 956// ------------------------------------------------------------------------- 957 958ssize_t AudioTrack::write(const void* buffer, size_t userSize) 959{ 960 961 if (mSharedBuffer != 0) return INVALID_OPERATION; 962 963 if (ssize_t(userSize) < 0) { 964 // sanity-check. user is most-likely passing an error code. 965 ALOGE("AudioTrack::write(buffer=%p, size=%u (%d)", 966 buffer, userSize, userSize); 967 return BAD_VALUE; 968 } 969 970 ALOGV("write %p: %d bytes, mActive=%d", this, userSize, mActive); 971 972 // acquire a strong reference on the IMemory and IAudioTrack so that they cannot be destroyed 973 // while we are accessing the cblk 974 mLock.lock(); 975 sp <IAudioTrack> audioTrack = mAudioTrack; 976 sp <IMemory> iMem = mCblkMemory; 977 mLock.unlock(); 978 979 ssize_t written = 0; 980 const int8_t *src = (const int8_t *)buffer; 981 Buffer audioBuffer; 982 size_t frameSz = frameSize(); 983 984 do { 985 audioBuffer.frameCount = userSize/frameSz; 986 987 // Calling obtainBuffer() with a negative wait count causes 988 // an (almost) infinite wait time. 989 status_t err = obtainBuffer(&audioBuffer, -1); 990 if (err < 0) { 991 // out of buffers, return #bytes written 992 if (err == status_t(NO_MORE_BUFFERS)) 993 break; 994 return ssize_t(err); 995 } 996 997 size_t toWrite; 998 999 if (mFormat == AUDIO_FORMAT_PCM_8_BIT && !(mFlags & AUDIO_POLICY_OUTPUT_FLAG_DIRECT)) { 1000 // Divide capacity by 2 to take expansion into account 1001 toWrite = audioBuffer.size>>1; 1002 // 8 to 16 bit conversion 1003 int count = toWrite; 1004 int16_t *dst = (int16_t *)(audioBuffer.i8); 1005 while(count--) { 1006 *dst++ = (int16_t)(*src++^0x80) << 8; 1007 } 1008 } else { 1009 toWrite = audioBuffer.size; 1010 memcpy(audioBuffer.i8, src, toWrite); 1011 src += toWrite; 1012 } 1013 userSize -= toWrite; 1014 written += toWrite; 1015 1016 releaseBuffer(&audioBuffer); 1017 } while (userSize >= frameSz); 1018 1019 return written; 1020} 1021 1022// ------------------------------------------------------------------------- 1023 1024bool AudioTrack::processAudioBuffer(const sp<AudioTrackThread>& thread) 1025{ 1026 Buffer audioBuffer; 1027 uint32_t frames; 1028 size_t writtenSize; 1029 1030 mLock.lock(); 1031 // acquire a strong reference on the IMemory and IAudioTrack so that they cannot be destroyed 1032 // while we are accessing the cblk 1033 sp <IAudioTrack> audioTrack = mAudioTrack; 1034 sp <IMemory> iMem = mCblkMemory; 1035 audio_track_cblk_t* cblk = mCblk; 1036 bool active = mActive; 1037 mLock.unlock(); 1038 1039 // Manage underrun callback 1040 if (active && (cblk->framesAvailable() == cblk->frameCount)) { 1041 ALOGV("Underrun user: %x, server: %x, flags %04x", cblk->user, cblk->server, cblk->flags); 1042 if (!(android_atomic_or(CBLK_UNDERRUN_ON, &cblk->flags) & CBLK_UNDERRUN_MSK)) { 1043 mCbf(EVENT_UNDERRUN, mUserData, 0); 1044 if (cblk->server == cblk->frameCount) { 1045 mCbf(EVENT_BUFFER_END, mUserData, 0); 1046 } 1047 if (mSharedBuffer != 0) return false; 1048 } 1049 } 1050 1051 // Manage loop end callback 1052 while (mLoopCount > cblk->loopCount) { 1053 int loopCount = -1; 1054 mLoopCount--; 1055 if (mLoopCount >= 0) loopCount = mLoopCount; 1056 1057 mCbf(EVENT_LOOP_END, mUserData, (void *)&loopCount); 1058 } 1059 1060 // Manage marker callback 1061 if (!mMarkerReached && (mMarkerPosition > 0)) { 1062 if (cblk->server >= mMarkerPosition) { 1063 mCbf(EVENT_MARKER, mUserData, (void *)&mMarkerPosition); 1064 mMarkerReached = true; 1065 } 1066 } 1067 1068 // Manage new position callback 1069 if (mUpdatePeriod > 0) { 1070 while (cblk->server >= mNewPosition) { 1071 mCbf(EVENT_NEW_POS, mUserData, (void *)&mNewPosition); 1072 mNewPosition += mUpdatePeriod; 1073 } 1074 } 1075 1076 // If Shared buffer is used, no data is requested from client. 1077 if (mSharedBuffer != 0) { 1078 frames = 0; 1079 } else { 1080 frames = mRemainingFrames; 1081 } 1082 1083 int32_t waitCount = -1; 1084 if (mUpdatePeriod || (!mMarkerReached && mMarkerPosition) || mLoopCount) { 1085 waitCount = 1; 1086 } 1087 1088 do { 1089 1090 audioBuffer.frameCount = frames; 1091 1092 // Calling obtainBuffer() with a wait count of 1 1093 // limits wait time to WAIT_PERIOD_MS. This prevents from being 1094 // stuck here not being able to handle timed events (position, markers, loops). 1095 status_t err = obtainBuffer(&audioBuffer, waitCount); 1096 if (err < NO_ERROR) { 1097 if (err != TIMED_OUT) { 1098 ALOGE_IF(err != status_t(NO_MORE_BUFFERS), "Error obtaining an audio buffer, giving up."); 1099 return false; 1100 } 1101 break; 1102 } 1103 if (err == status_t(STOPPED)) return false; 1104 1105 // Divide buffer size by 2 to take into account the expansion 1106 // due to 8 to 16 bit conversion: the callback must fill only half 1107 // of the destination buffer 1108 if (mFormat == AUDIO_FORMAT_PCM_8_BIT && !(mFlags & AUDIO_POLICY_OUTPUT_FLAG_DIRECT)) { 1109 audioBuffer.size >>= 1; 1110 } 1111 1112 size_t reqSize = audioBuffer.size; 1113 mCbf(EVENT_MORE_DATA, mUserData, &audioBuffer); 1114 writtenSize = audioBuffer.size; 1115 1116 // Sanity check on returned size 1117 if (ssize_t(writtenSize) <= 0) { 1118 // The callback is done filling buffers 1119 // Keep this thread going to handle timed events and 1120 // still try to get more data in intervals of WAIT_PERIOD_MS 1121 // but don't just loop and block the CPU, so wait 1122 usleep(WAIT_PERIOD_MS*1000); 1123 break; 1124 } 1125 if (writtenSize > reqSize) writtenSize = reqSize; 1126 1127 if (mFormat == AUDIO_FORMAT_PCM_8_BIT && !(mFlags & AUDIO_POLICY_OUTPUT_FLAG_DIRECT)) { 1128 // 8 to 16 bit conversion 1129 const int8_t *src = audioBuffer.i8 + writtenSize-1; 1130 int count = writtenSize; 1131 int16_t *dst = audioBuffer.i16 + writtenSize-1; 1132 while(count--) { 1133 *dst-- = (int16_t)(*src--^0x80) << 8; 1134 } 1135 writtenSize <<= 1; 1136 } 1137 1138 audioBuffer.size = writtenSize; 1139 // NOTE: mCblk->frameSize is not equal to AudioTrack::frameSize() for 1140 // 8 bit PCM data: in this case, mCblk->frameSize is based on a sample size of 1141 // 16 bit. 1142 audioBuffer.frameCount = writtenSize/mCblk->frameSize; 1143 1144 frames -= audioBuffer.frameCount; 1145 1146 releaseBuffer(&audioBuffer); 1147 } 1148 while (frames); 1149 1150 if (frames == 0) { 1151 mRemainingFrames = mNotificationFramesAct; 1152 } else { 1153 mRemainingFrames = frames; 1154 } 1155 return true; 1156} 1157 1158// must be called with mLock and cblk.lock held. Callers must also hold strong references on 1159// the IAudioTrack and IMemory in case they are recreated here. 1160// If the IAudioTrack is successfully restored, the cblk pointer is updated 1161status_t AudioTrack::restoreTrack_l(audio_track_cblk_t*& cblk, bool fromStart) 1162{ 1163 status_t result; 1164 1165 if (!(android_atomic_or(CBLK_RESTORING_ON, &cblk->flags) & CBLK_RESTORING_MSK)) { 1166 ALOGW("dead IAudioTrack, creating a new one from %s TID %d", 1167 fromStart ? "start()" : "obtainBuffer()", gettid()); 1168 1169 // signal old cblk condition so that other threads waiting for available buffers stop 1170 // waiting now 1171 cblk->cv.broadcast(); 1172 cblk->lock.unlock(); 1173 1174 // refresh the audio configuration cache in this process to make sure we get new 1175 // output parameters in getOutput_l() and createTrack_l() 1176 AudioSystem::clearAudioConfigCache(); 1177 1178 // if the new IAudioTrack is created, createTrack_l() will modify the 1179 // following member variables: mAudioTrack, mCblkMemory and mCblk. 1180 // It will also delete the strong references on previous IAudioTrack and IMemory 1181 result = createTrack_l(mStreamType, 1182 cblk->sampleRate, 1183 mFormat, 1184 mChannelMask, 1185 mFrameCount, 1186 mFlags, 1187 mSharedBuffer, 1188 getOutput_l(), 1189 false); 1190 1191 if (result == NO_ERROR) { 1192 uint32_t user = cblk->user; 1193 uint32_t server = cblk->server; 1194 // restore write index and set other indexes to reflect empty buffer status 1195 mCblk->user = user; 1196 mCblk->server = user; 1197 mCblk->userBase = user; 1198 mCblk->serverBase = user; 1199 // restore loop: this is not guaranteed to succeed if new frame count is not 1200 // compatible with loop length 1201 setLoop_l(cblk->loopStart, cblk->loopEnd, cblk->loopCount); 1202 if (!fromStart) { 1203 mCblk->bufferTimeoutMs = MAX_RUN_TIMEOUT_MS; 1204 // Make sure that a client relying on callback events indicating underrun or 1205 // the actual amount of audio frames played (e.g SoundPool) receives them. 1206 if (mSharedBuffer == 0) { 1207 uint32_t frames = 0; 1208 if (user > server) { 1209 frames = ((user - server) > mCblk->frameCount) ? 1210 mCblk->frameCount : (user - server); 1211 memset(mCblk->buffers, 0, frames * mCblk->frameSize); 1212 } 1213 // restart playback even if buffer is not completely filled. 1214 android_atomic_or(CBLK_FORCEREADY_ON, &mCblk->flags); 1215 // stepUser() clears CBLK_UNDERRUN_ON flag enabling underrun callbacks to 1216 // the client 1217 mCblk->stepUser(frames); 1218 } 1219 } 1220 if (mActive) { 1221 result = mAudioTrack->start(); 1222 ALOGW_IF(result != NO_ERROR, "restoreTrack_l() start() failed status %d", result); 1223 } 1224 if (fromStart && result == NO_ERROR) { 1225 mNewPosition = mCblk->server + mUpdatePeriod; 1226 } 1227 } 1228 if (result != NO_ERROR) { 1229 android_atomic_and(~CBLK_RESTORING_ON, &cblk->flags); 1230 ALOGW_IF(result != NO_ERROR, "restoreTrack_l() failed status %d", result); 1231 } 1232 mRestoreStatus = result; 1233 // signal old cblk condition for other threads waiting for restore completion 1234 android_atomic_or(CBLK_RESTORED_ON, &cblk->flags); 1235 cblk->cv.broadcast(); 1236 } else { 1237 if (!(cblk->flags & CBLK_RESTORED_MSK)) { 1238 ALOGW("dead IAudioTrack, waiting for a new one TID %d", gettid()); 1239 mLock.unlock(); 1240 result = cblk->cv.waitRelative(cblk->lock, milliseconds(RESTORE_TIMEOUT_MS)); 1241 if (result == NO_ERROR) { 1242 result = mRestoreStatus; 1243 } 1244 cblk->lock.unlock(); 1245 mLock.lock(); 1246 } else { 1247 ALOGW("dead IAudioTrack, already restored TID %d", gettid()); 1248 result = mRestoreStatus; 1249 cblk->lock.unlock(); 1250 } 1251 } 1252 ALOGV("restoreTrack_l() status %d mActive %d cblk %p, old cblk %p flags %08x old flags %08x", 1253 result, mActive, mCblk, cblk, mCblk->flags, cblk->flags); 1254 1255 if (result == NO_ERROR) { 1256 // from now on we switch to the newly created cblk 1257 cblk = mCblk; 1258 } 1259 cblk->lock.lock(); 1260 1261 ALOGW_IF(result != NO_ERROR, "restoreTrack_l() error %d TID %d", result, gettid()); 1262 1263 return result; 1264} 1265 1266status_t AudioTrack::dump(int fd, const Vector<String16>& args) const 1267{ 1268 1269 const size_t SIZE = 256; 1270 char buffer[SIZE]; 1271 String8 result; 1272 1273 result.append(" AudioTrack::dump\n"); 1274 snprintf(buffer, 255, " stream type(%d), left - right volume(%f, %f)\n", mStreamType, mVolume[0], mVolume[1]); 1275 result.append(buffer); 1276 snprintf(buffer, 255, " format(%d), channel count(%d), frame count(%d)\n", mFormat, mChannelCount, mCblk->frameCount); 1277 result.append(buffer); 1278 snprintf(buffer, 255, " sample rate(%d), status(%d), muted(%d)\n", (mCblk == 0) ? 0 : mCblk->sampleRate, mStatus, mMuted); 1279 result.append(buffer); 1280 snprintf(buffer, 255, " active(%d), latency (%d)\n", mActive, mLatency); 1281 result.append(buffer); 1282 ::write(fd, result.string(), result.size()); 1283 return NO_ERROR; 1284} 1285 1286// ========================================================================= 1287 1288AudioTrack::AudioTrackThread::AudioTrackThread(AudioTrack& receiver, bool bCanCallJava) 1289 : Thread(bCanCallJava), mReceiver(receiver) 1290{ 1291} 1292 1293bool AudioTrack::AudioTrackThread::threadLoop() 1294{ 1295 return mReceiver.processAudioBuffer(this); 1296} 1297 1298status_t AudioTrack::AudioTrackThread::readyToRun() 1299{ 1300 return NO_ERROR; 1301} 1302 1303void AudioTrack::AudioTrackThread::onFirstRef() 1304{ 1305} 1306 1307// ========================================================================= 1308 1309 1310audio_track_cblk_t::audio_track_cblk_t() 1311 : lock(Mutex::SHARED), cv(Condition::SHARED), user(0), server(0), 1312 userBase(0), serverBase(0), buffers(0), frameCount(0), 1313 loopStart(UINT_MAX), loopEnd(UINT_MAX), loopCount(0), volumeLR(0), 1314 sendLevel(0), flags(0) 1315{ 1316} 1317 1318uint32_t audio_track_cblk_t::stepUser(uint32_t frameCount) 1319{ 1320 uint32_t u = user; 1321 1322 u += frameCount; 1323 // Ensure that user is never ahead of server for AudioRecord 1324 if (flags & CBLK_DIRECTION_MSK) { 1325 // If stepServer() has been called once, switch to normal obtainBuffer() timeout period 1326 if (bufferTimeoutMs == MAX_STARTUP_TIMEOUT_MS-1) { 1327 bufferTimeoutMs = MAX_RUN_TIMEOUT_MS; 1328 } 1329 } else if (u > server) { 1330 ALOGW("stepServer occurred after track reset"); 1331 u = server; 1332 } 1333 1334 if (u >= userBase + this->frameCount) { 1335 userBase += this->frameCount; 1336 } 1337 1338 user = u; 1339 1340 // Clear flow control error condition as new data has been written/read to/from buffer. 1341 if (flags & CBLK_UNDERRUN_MSK) { 1342 android_atomic_and(~CBLK_UNDERRUN_MSK, &flags); 1343 } 1344 1345 return u; 1346} 1347 1348bool audio_track_cblk_t::stepServer(uint32_t frameCount) 1349{ 1350 if (!tryLock()) { 1351 ALOGW("stepServer() could not lock cblk"); 1352 return false; 1353 } 1354 1355 uint32_t s = server; 1356 1357 s += frameCount; 1358 if (flags & CBLK_DIRECTION_MSK) { 1359 // Mark that we have read the first buffer so that next time stepUser() is called 1360 // we switch to normal obtainBuffer() timeout period 1361 if (bufferTimeoutMs == MAX_STARTUP_TIMEOUT_MS) { 1362 bufferTimeoutMs = MAX_STARTUP_TIMEOUT_MS - 1; 1363 } 1364 // It is possible that we receive a flush() 1365 // while the mixer is processing a block: in this case, 1366 // stepServer() is called After the flush() has reset u & s and 1367 // we have s > u 1368 if (s > user) { 1369 ALOGW("stepServer occurred after track reset"); 1370 s = user; 1371 } 1372 } 1373 1374 if (s >= loopEnd) { 1375 ALOGW_IF(s > loopEnd, "stepServer: s %u > loopEnd %u", s, loopEnd); 1376 s = loopStart; 1377 if (--loopCount == 0) { 1378 loopEnd = UINT_MAX; 1379 loopStart = UINT_MAX; 1380 } 1381 } 1382 if (s >= serverBase + this->frameCount) { 1383 serverBase += this->frameCount; 1384 } 1385 1386 server = s; 1387 1388 if (!(flags & CBLK_INVALID_MSK)) { 1389 cv.signal(); 1390 } 1391 lock.unlock(); 1392 return true; 1393} 1394 1395void* audio_track_cblk_t::buffer(uint32_t offset) const 1396{ 1397 return (int8_t *)buffers + (offset - userBase) * frameSize; 1398} 1399 1400uint32_t audio_track_cblk_t::framesAvailable() 1401{ 1402 Mutex::Autolock _l(lock); 1403 return framesAvailable_l(); 1404} 1405 1406uint32_t audio_track_cblk_t::framesAvailable_l() 1407{ 1408 uint32_t u = user; 1409 uint32_t s = server; 1410 1411 if (flags & CBLK_DIRECTION_MSK) { 1412 uint32_t limit = (s < loopStart) ? s : loopStart; 1413 return limit + frameCount - u; 1414 } else { 1415 return frameCount + u - s; 1416 } 1417} 1418 1419uint32_t audio_track_cblk_t::framesReady() 1420{ 1421 uint32_t u = user; 1422 uint32_t s = server; 1423 1424 if (flags & CBLK_DIRECTION_MSK) { 1425 if (u < loopEnd) { 1426 return u - s; 1427 } else { 1428 // do not block on mutex shared with client on AudioFlinger side 1429 if (!tryLock()) { 1430 ALOGW("framesReady() could not lock cblk"); 1431 return 0; 1432 } 1433 uint32_t frames = UINT_MAX; 1434 if (loopCount >= 0) { 1435 frames = (loopEnd - loopStart)*loopCount + u - s; 1436 } 1437 lock.unlock(); 1438 return frames; 1439 } 1440 } else { 1441 return s - u; 1442 } 1443} 1444 1445bool audio_track_cblk_t::tryLock() 1446{ 1447 // the code below simulates lock-with-timeout 1448 // we MUST do this to protect the AudioFlinger server 1449 // as this lock is shared with the client. 1450 status_t err; 1451 1452 err = lock.tryLock(); 1453 if (err == -EBUSY) { // just wait a bit 1454 usleep(1000); 1455 err = lock.tryLock(); 1456 } 1457 if (err != NO_ERROR) { 1458 // probably, the client just died. 1459 return false; 1460 } 1461 return true; 1462} 1463 1464// ------------------------------------------------------------------------- 1465 1466}; // namespace android 1467