tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

ReverbInputBuffer.cpp (3162B)

      1 /*
      2 * Copyright (C) 2010 Google Inc. All rights reserved.
      3 *
      4 * Redistribution and use in source and binary forms, with or without
      5 * modification, are permitted provided that the following conditions
      6 * are met:
      7 *
      8 * 1.  Redistributions of source code must retain the above copyright
      9 *     notice, this list of conditions and the following disclaimer.
     10 * 2.  Redistributions in binary form must reproduce the above copyright
     11 *     notice, this list of conditions and the following disclaimer in the
     12 *     documentation and/or other materials provided with the distribution.
     13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
     14 *     its contributors may be used to endorse or promote products derived
     15 *     from this software without specific prior written permission.
     16 *
     17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
     18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
     21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27 */
     28 
     29 #include "ReverbInputBuffer.h"
     30 
     31 #include "mozilla/PodOperations.h"
     32 
     33 using namespace mozilla;
     34 
     35 namespace WebCore {
     36 
     37 ReverbInputBuffer::ReverbInputBuffer(size_t length) : m_writeIndex(0) {
     38  m_buffer.SetLength(length);
     39  PodZero(m_buffer.Elements(), length);
     40 }
     41 
     42 void ReverbInputBuffer::write(const float* sourceP, size_t numberOfFrames) {
     43  // m_writeIndex is atomic and checked by other threads, so only touch
     44  // it at the start and end.
     45  size_t bufferLength = m_buffer.Length();
     46  size_t index = m_writeIndex;
     47  size_t newIndex = index + numberOfFrames;
     48 
     49  MOZ_RELEASE_ASSERT(newIndex <= bufferLength);
     50 
     51  memcpy(m_buffer.Elements() + index, sourceP, sizeof(float) * numberOfFrames);
     52 
     53  if (newIndex >= bufferLength) {
     54    newIndex = 0;
     55  }
     56  m_writeIndex = newIndex;
     57 }
     58 
     59 float* ReverbInputBuffer::directReadFrom(int* readIndex,
     60                                         size_t numberOfFrames) {
     61  size_t bufferLength = m_buffer.Length();
     62  bool isPointerGood = readIndex && *readIndex >= 0 &&
     63                       *readIndex + numberOfFrames <= bufferLength;
     64  MOZ_ASSERT(isPointerGood);
     65  if (!isPointerGood) {
     66    // Should never happen in practice but return pointer to start of buffer
     67    // (avoid crash)
     68    if (readIndex) *readIndex = 0;
     69    return m_buffer.Elements();
     70  }
     71 
     72  float* sourceP = m_buffer.Elements();
     73  float* p = sourceP + *readIndex;
     74 
     75  // Update readIndex
     76  *readIndex = (*readIndex + numberOfFrames) % bufferLength;
     77 
     78  return p;
     79 }
     80 
     81 void ReverbInputBuffer::reset() {
     82  PodZero(m_buffer.Elements(), m_buffer.Length());
     83  m_writeIndex = 0;
     84 }
     85 
     86 }  // namespace WebCore