16b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner/* 26b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * Copyright (C) 2010, Google Inc. All rights reserved. 36b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * 46b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * Redistribution and use in source and binary forms, with or without 56b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * modification, are permitted provided that the following conditions 66b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * are met: 76b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * 1. Redistributions of source code must retain the above copyright 86b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * notice, this list of conditions and the following disclaimer. 96b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * 2. Redistributions in binary form must reproduce the above copyright 106b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * notice, this list of conditions and the following disclaimer in the 116b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * documentation and/or other materials provided with the distribution. 126b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * 136b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY 146b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 156b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 166b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY 176b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 186b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 196b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 206b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 216b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 226b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 236b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner */ 246b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 256b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "config.h" 266b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 276b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#if ENABLE(WEB_AUDIO) 286b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 296b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "JavaScriptAudioNode.h" 306b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 316b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "AudioBuffer.h" 326b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "AudioBus.h" 336b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "AudioContext.h" 346b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "AudioNodeInput.h" 356b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "AudioNodeOutput.h" 366b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "AudioProcessingEvent.h" 376b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "Document.h" 386b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include "Float32Array.h" 396b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#include <wtf/MainThread.h> 406b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 416b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennernamespace WebCore { 426b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 436b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennerconst size_t DefaultBufferSize = 4096; 446b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 456b70adc33054f8aee8c54d0f460458a9df11b8a5Russell BrennerPassRefPtr<JavaScriptAudioNode> JavaScriptAudioNode::create(AudioContext* context, double sampleRate, size_t bufferSize, unsigned numberOfInputs, unsigned numberOfOutputs) 466b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 476b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return adoptRef(new JavaScriptAudioNode(context, sampleRate, bufferSize, numberOfInputs, numberOfOutputs)); 486b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 496b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 506b70adc33054f8aee8c54d0f460458a9df11b8a5Russell BrennerJavaScriptAudioNode::JavaScriptAudioNode(AudioContext* context, double sampleRate, size_t bufferSize, unsigned numberOfInputs, unsigned numberOfOutputs) 516b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner : AudioNode(context, sampleRate) 526b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner , m_doubleBufferIndex(0) 536b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner , m_doubleBufferIndexForEvent(0) 546b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner , m_bufferSize(bufferSize) 556b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner , m_bufferReadWriteIndex(0) 566b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner , m_isRequestOutstanding(false) 576b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 586b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Check for valid buffer size. 596b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner switch (bufferSize) { 606b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner case 256: 616b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner case 512: 626b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner case 1024: 636b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner case 2048: 646b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner case 4096: 656b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner case 8192: 666b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner case 16384: 676b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_bufferSize = bufferSize; 686b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner break; 696b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner default: 706b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_bufferSize = DefaultBufferSize; 716b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } 726b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 736b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Regardless of the allowed buffer sizes above, we still need to process at the granularity of the AudioNode. 746b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (m_bufferSize < AudioNode::ProcessingSizeInFrames) 756b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_bufferSize = AudioNode::ProcessingSizeInFrames; 766b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 776b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // FIXME: Right now we're hardcoded to single input and single output. 786b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Although the specification says this is OK for a simple implementation, multiple inputs and outputs would be good. 796b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT_UNUSED(numberOfInputs, numberOfInputs == 1); 806b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT_UNUSED(numberOfOutputs, numberOfOutputs == 1); 816b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner addInput(adoptPtr(new AudioNodeInput(this))); 826b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner addOutput(adoptPtr(new AudioNodeOutput(this, 2))); 836b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 846b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner setType(NodeTypeJavaScript); 856b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 866b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner initialize(); 876b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 886b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 896b70adc33054f8aee8c54d0f460458a9df11b8a5Russell BrennerJavaScriptAudioNode::~JavaScriptAudioNode() 906b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 916b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner uninitialize(); 926b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 936b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 946b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennervoid JavaScriptAudioNode::initialize() 956b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 966b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (isInitialized()) 976b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 986b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 996b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner double sampleRate = context()->sampleRate(); 1006b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1016b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Create double buffers on both the input and output sides. 1026b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // These AudioBuffers will be directly accessed in the main thread by JavaScript. 1036b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner for (unsigned i = 0; i < 2; ++i) { 1046b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_inputBuffers.append(AudioBuffer::create(2, bufferSize(), sampleRate)); 1056b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_outputBuffers.append(AudioBuffer::create(2, bufferSize(), sampleRate)); 1066b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } 1076b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1086b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioNode::initialize(); 1096b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 1106b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1116b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennervoid JavaScriptAudioNode::uninitialize() 1126b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 1136b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!isInitialized()) 1146b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 1156b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1166b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_inputBuffers.clear(); 1176b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_outputBuffers.clear(); 1186b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1196b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioNode::uninitialize(); 1206b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 1216b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1226b70adc33054f8aee8c54d0f460458a9df11b8a5Russell BrennerJavaScriptAudioNode* JavaScriptAudioNode::toJavaScriptAudioNode() 1236b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 1246b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return this; 1256b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 1266b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1276b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennervoid JavaScriptAudioNode::process(size_t framesToProcess) 1286b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 1296b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Discussion about inputs and outputs: 1306b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // As in other AudioNodes, JavaScriptAudioNode uses an AudioBus for its input and output (see inputBus and outputBus below). 1316b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Additionally, there is a double-buffering for input and output which is exposed directly to JavaScript (see inputBuffer and outputBuffer below). 1326b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // This node is the producer for inputBuffer and the consumer for outputBuffer. 1336b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // The JavaScript code is the consumer of inputBuffer and the producer for outputBuffer. 1346b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1356b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Get input and output busses. 1366b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioBus* inputBus = this->input(0)->bus(); 1376b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioBus* outputBus = this->output(0)->bus(); 1386b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1396b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Get input and output buffers. We double-buffer both the input and output sides. 1406b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner unsigned doubleBufferIndex = this->doubleBufferIndex(); 1416b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner bool isDoubleBufferIndexGood = doubleBufferIndex < 2 && doubleBufferIndex < m_inputBuffers.size() && doubleBufferIndex < m_outputBuffers.size(); 1426b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(isDoubleBufferIndexGood); 1436b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!isDoubleBufferIndexGood) 1446b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 1456b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1466b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioBuffer* inputBuffer = m_inputBuffers[doubleBufferIndex].get(); 1476b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioBuffer* outputBuffer = m_outputBuffers[doubleBufferIndex].get(); 1486b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1496b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Check the consistency of input and output buffers. 1506b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner bool buffersAreGood = inputBuffer && outputBuffer && bufferSize() == inputBuffer->length() && bufferSize() == outputBuffer->length() 1516b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner && m_bufferReadWriteIndex + framesToProcess <= bufferSize(); 1526b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(buffersAreGood); 1536b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!buffersAreGood) 1546b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 1556b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1566b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // We assume that bufferSize() is evenly divisible by framesToProcess - should always be true, but we should still check. 1576b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner bool isFramesToProcessGood = framesToProcess && bufferSize() >= framesToProcess && !(bufferSize() % framesToProcess); 1586b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(isFramesToProcessGood); 1596b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!isFramesToProcessGood) 1606b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 1616b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1626b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner unsigned numberOfInputChannels = inputBus->numberOfChannels(); 1636b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1646b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner bool channelsAreGood = (numberOfInputChannels == 1 || numberOfInputChannels == 2) && outputBus->numberOfChannels() == 2; 1656b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(channelsAreGood); 1666b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!channelsAreGood) 1676b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 1686b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1696b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner float* sourceL = inputBus->channel(0)->data(); 1706b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner float* sourceR = numberOfInputChannels > 1 ? inputBus->channel(1)->data() : 0; 1716b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner float* destinationL = outputBus->channel(0)->data(); 1726b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner float* destinationR = outputBus->channel(1)->data(); 1736b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1746b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Copy from the input to the input buffer. See "buffersAreGood" check above for safety. 1756b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner size_t bytesToCopy = sizeof(float) * framesToProcess; 1766b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner memcpy(inputBuffer->getChannelData(0)->data() + m_bufferReadWriteIndex, sourceL, bytesToCopy); 1776b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1786b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (numberOfInputChannels == 2) 1796b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner memcpy(inputBuffer->getChannelData(1)->data() + m_bufferReadWriteIndex, sourceR, bytesToCopy); 1806b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner else if (numberOfInputChannels == 1) { 1816b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // If the input is mono, then also copy the mono input to the right channel of the AudioBuffer which the AudioProcessingEvent uses. 1826b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // FIXME: it is likely the audio API will evolve to present an AudioBuffer with the same number of channels as our input. 1836b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner memcpy(inputBuffer->getChannelData(1)->data() + m_bufferReadWriteIndex, sourceL, bytesToCopy); 1846b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } 1856b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1866b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Copy from the output buffer to the output. See "buffersAreGood" check above for safety. 1876b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner memcpy(destinationL, outputBuffer->getChannelData(0)->data() + m_bufferReadWriteIndex, bytesToCopy); 1886b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner memcpy(destinationR, outputBuffer->getChannelData(1)->data() + m_bufferReadWriteIndex, bytesToCopy); 1896b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1906b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Update the buffering index. 1916b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_bufferReadWriteIndex = (m_bufferReadWriteIndex + framesToProcess) % bufferSize(); 1926b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 1936b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // m_bufferReadWriteIndex will wrap back around to 0 when the current input and output buffers are full. 1946b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // When this happens, fire an event and swap buffers. 1956b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!m_bufferReadWriteIndex) { 1966b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Avoid building up requests on the main thread to fire process events when they're not being handled. 1976b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // This could be a problem if the main thread is very busy doing other things and is being held up handling previous requests. 1986b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (m_isRequestOutstanding) { 1996b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // We're late in handling the previous request. The main thread must be very busy. 2006b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // The best we can do is clear out the buffer ourself here. 2016b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner outputBuffer->zero(); 2026b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } else { 2036b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Reference ourself so we don't accidentally get deleted before fireProcessEvent() gets called. 2046b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ref(); 2056b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2066b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Fire the event on the main thread, not this one (which is the realtime audio thread). 2076b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_doubleBufferIndexForEvent = m_doubleBufferIndex; 2086b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_isRequestOutstanding = true; 20981bc750723a18f21cd17d1b173cd2a4dda9cea6eBen Murdoch callOnMainThread(fireProcessEventDispatch, this); 2106b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } 2116b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2126b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner swapBuffers(); 2136b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } 2146b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 2156b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2166b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennervoid JavaScriptAudioNode::fireProcessEventDispatch(void* userData) 2176b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 2186b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner JavaScriptAudioNode* jsAudioNode = static_cast<JavaScriptAudioNode*>(userData); 2196b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(jsAudioNode); 2206b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!jsAudioNode) 2216b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 2226b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2236b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner jsAudioNode->fireProcessEvent(); 2246b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2256b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // De-reference to match the ref() call in process(). 2266b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner jsAudioNode->deref(); 2276b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 2286b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2296b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennervoid JavaScriptAudioNode::fireProcessEvent() 2306b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 2316b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(isMainThread() && m_isRequestOutstanding); 2326b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2336b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner bool isIndexGood = m_doubleBufferIndexForEvent < 2; 2346b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(isIndexGood); 2356b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!isIndexGood) 2366b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 2376b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2386b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioBuffer* inputBuffer = m_inputBuffers[m_doubleBufferIndexForEvent].get(); 2396b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner AudioBuffer* outputBuffer = m_outputBuffers[m_doubleBufferIndexForEvent].get(); 2406b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner ASSERT(inputBuffer && outputBuffer); 2416b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (!inputBuffer || !outputBuffer) 2426b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return; 2436b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2446b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Avoid firing the event if the document has already gone away. 2456b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner if (context()->hasDocument()) { 2466b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Let the audio thread know we've gotten to the point where it's OK for it to make another request. 2476b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_isRequestOutstanding = false; 2486b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2496b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner // Call the JavaScript event handler which will do the audio processing. 2506b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner dispatchEvent(AudioProcessingEvent::create(inputBuffer, outputBuffer)); 2516b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } 2526b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 2536b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2546b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brennervoid JavaScriptAudioNode::reset() 2556b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 2566b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_bufferReadWriteIndex = 0; 2576b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_doubleBufferIndex = 0; 2586b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2596b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner for (unsigned i = 0; i < 2; ++i) { 2606b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_inputBuffers[i]->zero(); 2616b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner m_outputBuffers[i]->zero(); 2626b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner } 2636b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 2646b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2656b70adc33054f8aee8c54d0f460458a9df11b8a5Russell BrennerScriptExecutionContext* JavaScriptAudioNode::scriptExecutionContext() const 2666b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner{ 2676b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner return const_cast<JavaScriptAudioNode*>(this)->context()->document(); 2686b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} 2696b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2706b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner} // namespace WebCore 2716b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner 2726b70adc33054f8aee8c54d0f460458a9df11b8a5Russell Brenner#endif // ENABLE(WEB_AUDIO) 273