|  | /* | 
|  | *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved. | 
|  | * | 
|  | *  Use of this source code is governed by a BSD-style license | 
|  | *  that can be found in the LICENSE file in the root of the source | 
|  | *  tree. An additional intellectual property rights grant can be found | 
|  | *  in the file PATENTS.  All contributing project authors may | 
|  | *  be found in the AUTHORS file in the root of the source tree. | 
|  | */ | 
|  |  | 
|  | #include "modules/audio_processing/echo_detector/circular_buffer.h" | 
|  |  | 
|  | #include <algorithm> | 
|  | #include <cstddef> | 
|  | #include <optional> | 
|  |  | 
|  | #include "rtc_base/checks.h" | 
|  |  | 
|  | namespace webrtc { | 
|  |  | 
|  | CircularBuffer::CircularBuffer(size_t size) : buffer_(size) {} | 
|  | CircularBuffer::~CircularBuffer() = default; | 
|  |  | 
|  | void CircularBuffer::Push(float value) { | 
|  | buffer_[next_insertion_index_] = value; | 
|  | ++next_insertion_index_; | 
|  | next_insertion_index_ %= buffer_.size(); | 
|  | RTC_DCHECK_LT(next_insertion_index_, buffer_.size()); | 
|  | nr_elements_in_buffer_ = std::min(nr_elements_in_buffer_ + 1, buffer_.size()); | 
|  | RTC_DCHECK_LE(nr_elements_in_buffer_, buffer_.size()); | 
|  | } | 
|  |  | 
|  | std::optional<float> CircularBuffer::Pop() { | 
|  | if (nr_elements_in_buffer_ == 0) { | 
|  | return std::nullopt; | 
|  | } | 
|  | const size_t index = | 
|  | (buffer_.size() + next_insertion_index_ - nr_elements_in_buffer_) % | 
|  | buffer_.size(); | 
|  | RTC_DCHECK_LT(index, buffer_.size()); | 
|  | --nr_elements_in_buffer_; | 
|  | return buffer_[index]; | 
|  | } | 
|  |  | 
|  | void CircularBuffer::Clear() { | 
|  | std::fill(buffer_.begin(), buffer_.end(), 0.f); | 
|  | next_insertion_index_ = 0; | 
|  | nr_elements_in_buffer_ = 0; | 
|  | } | 
|  |  | 
|  | }  // namespace webrtc |