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diff --git a/src/3rdparty/resonance-audio/resonance_audio/dsp/circular_buffer.h b/src/3rdparty/resonance-audio/resonance_audio/dsp/circular_buffer.h
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+/*
+Copyright 2018 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS-IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#ifndef RESONANCE_AUDIO_DSP_CIRCULAR_BUFFER_H_
+#define RESONANCE_AUDIO_DSP_CIRCULAR_BUFFER_H_
+
+#include "base/audio_buffer.h"
+
+namespace vraudio {
+// Class that implements a simple mono circular buffer, accepting input and
+// output of different length.
+class CircularBuffer {
+ public:
+  // Constructs a circular buffer.
+  //
+  // @param buffer_length The length of the Circular buffer. This value must be
+  //     at least |num_input_frames| + |num_output_frames| so that we can always
+  //     either add or remove data.
+  // @param num_input_frames Length of the input buffers in frames.
+  // @param num_output_frames Length of the output buffers in frames.
+  CircularBuffer(size_t buffer_length, size_t num_input_frames,
+                 size_t num_output_frames);
+
+  // Inserts a buffer of mono input into the |CircularBuffer| if space permits.
+  //
+  // @param input A channel of input data |num_input_frames| in length.
+  // @return True if there was space in the buffer and the input was
+  //     successfully inserted, false otherwise.
+  bool InsertBuffer(const AudioBuffer::Channel& input);
+
+  // Retrieves a buffer of output from the |CircularBuffer| if it contains
+  // sufficient data.
+  //
+  // @param output A channel to hold |num_output_frames| of output data. The
+  //     channel may be greater in length than |num_output_frames|, in this
+  //     case only the first |num_output_frames| will be overwritten.
+  // @return True if there was sufficient data in the buffer and the output was
+  //     successfully retrieved.
+  bool RetrieveBuffer(AudioBuffer::Channel* output);
+
+  // Retrieves a buffer of output from the |CircularBuffer| to an offset
+  // location in an output channel, provided it contains sufficient data.
+  //
+  // @param offset Number of samples of offset into the |output| channel.
+  // @param output A channel to hold |num_output_frames| of output data. The
+  //     channel may be greater in length than |num_output_frames| + |offset|,
+  //     in this case only the first |num_output_frames| after |offset| will be
+  //     overwritten.
+  // @return True if there was sufficient data in the buffer and the output was
+  //     successfully retrieved.
+  bool RetrieveBufferWithOffset(size_t offset, AudioBuffer::Channel* output);
+
+  // Returns the number of samples of data currently in the |CircularBuffer|.
+  //
+  // @return The number of samples of data currently in the buffer.
+  size_t GetOccupancy() const { return num_valid_frames_; }
+
+  // Resets the |CircularBuffer|.
+  void Clear();
+
+ private:
+  // Number of input frames to be inserted into the buffer.
+  const size_t num_input_frames_;
+
+  // Number of output frames to be retrieved from the buffer.
+  const size_t num_output_frames_;
+
+  // Mono audio buffer to hold the data.
+  AudioBuffer buffer_;
+
+  // Position at which we are writing into the buffer.
+  size_t write_cursor_;
+
+  // position at which we are reading from the buffer.
+  size_t read_cursor_;
+
+  // Number of frames of data currently stored within the buffer.
+  size_t num_valid_frames_;
+};
+
+}  // namespace vraudio
+
+#endif  // RESONANCE_AUDIO_DSP_CIRCULAR_BUFFER_H_