1 /*
2  *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "webrtc/common_audio/audio_ring_buffer.h"
12 
13 #include "webrtc/base/checks.h"
14 #include "webrtc/common_audio/ring_buffer.h"
15 
16 // This is a simple multi-channel wrapper over the ring_buffer.h C interface.
17 
18 namespace webrtc {
19 
AudioRingBuffer(size_t channels,size_t max_frames)20 AudioRingBuffer::AudioRingBuffer(size_t channels, size_t max_frames) {
21   buffers_.reserve(channels);
22   for (size_t i = 0; i < channels; ++i)
23     buffers_.push_back(WebRtc_CreateBuffer(max_frames, sizeof(float)));
24 }
25 
~AudioRingBuffer()26 AudioRingBuffer::~AudioRingBuffer() {
27   for (auto buf : buffers_)
28     WebRtc_FreeBuffer(buf);
29 }
30 
Write(const float * const * data,size_t channels,size_t frames)31 void AudioRingBuffer::Write(const float* const* data, size_t channels,
32                             size_t frames) {
33   RTC_DCHECK_EQ(buffers_.size(), channels);
34   for (size_t i = 0; i < channels; ++i) {
35     const size_t written = WebRtc_WriteBuffer(buffers_[i], data[i], frames);
36     RTC_CHECK_EQ(written, frames);
37   }
38 }
39 
Read(float * const * data,size_t channels,size_t frames)40 void AudioRingBuffer::Read(float* const* data, size_t channels, size_t frames) {
41   RTC_DCHECK_EQ(buffers_.size(), channels);
42   for (size_t i = 0; i < channels; ++i) {
43     const size_t read =
44         WebRtc_ReadBuffer(buffers_[i], nullptr, data[i], frames);
45     RTC_CHECK_EQ(read, frames);
46   }
47 }
48 
ReadFramesAvailable() const49 size_t AudioRingBuffer::ReadFramesAvailable() const {
50   // All buffers have the same amount available.
51   return WebRtc_available_read(buffers_[0]);
52 }
53 
WriteFramesAvailable() const54 size_t AudioRingBuffer::WriteFramesAvailable() const {
55   // All buffers have the same amount available.
56   return WebRtc_available_write(buffers_[0]);
57 }
58 
MoveReadPositionForward(size_t frames)59 void AudioRingBuffer::MoveReadPositionForward(size_t frames) {
60   for (auto buf : buffers_) {
61     const size_t moved =
62         static_cast<size_t>(WebRtc_MoveReadPtr(buf, static_cast<int>(frames)));
63     RTC_CHECK_EQ(moved, frames);
64   }
65 }
66 
MoveReadPositionBackward(size_t frames)67 void AudioRingBuffer::MoveReadPositionBackward(size_t frames) {
68   for (auto buf : buffers_) {
69     const size_t moved = static_cast<size_t>(
70         -WebRtc_MoveReadPtr(buf, -static_cast<int>(frames)));
71     RTC_CHECK_EQ(moved, frames);
72   }
73 }
74 
75 }  // namespace webrtc
76