chromium/base/containers/ring_buffer.h

// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_CONTAINERS_RING_BUFFER_H_
#define BASE_CONTAINERS_RING_BUFFER_H_

#include <stddef.h>

#include <array>

#include "base/check.h"
#include "base/memory/raw_ref.h"

namespace base {

// base::RingBuffer uses a fixed-size array, unlike base::circular_deque and
// std::deque, and so, one can access only the last |kSize| elements. Also, you
// can add elements to the front and read/modify random elements, but cannot
// remove elements from the back. Therefore, it does not have a |Size| method,
// only |BufferSize|, which is a constant, and |CurrentIndex|, which is the
// number of elements added so far.
//
// If the above is sufficient for your use case, base::RingBuffer should be more
// efficient than base::circular_deque.
template <typename T, size_t kSize>
class RingBuffer { … };

}  // namespace base

#endif  // BASE_CONTAINERS_RING_BUFFER_H_