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diff --git a/media/libcubeb/src/cubeb_ringbuffer.h b/media/libcubeb/src/cubeb_ringbuffer.h
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-/*
- * Copyright © 2016 Mozilla Foundation
- *
- * This program is made available under an ISC-style license.  See the
- * accompanying file LICENSE for details.
- */
-
-#ifndef CUBEB_RING_BUFFER_H
-#define CUBEB_RING_BUFFER_H
-
-#include "cubeb_utils.h"
-#include <algorithm>
-#include <atomic>
-#include <cstdint>
-#include <memory>
-#include <thread>
-
-/**
- * Single producer single consumer lock-free and wait-free ring buffer.
- *
- * This data structure allows producing data from one thread, and consuming it on
- * another thread, safely and without explicit synchronization. If used on two
- * threads, this data structure uses atomics for thread safety. It is possible
- * to disable the use of atomics at compile time and only use this data
- * structure on one thread.
- *
- * The role for the producer and the consumer must be constant, i.e., the
- * producer should always be on one thread and the consumer should always be on
- * another thread.
- *
- * Some words about the inner workings of this class:
- * - Capacity is fixed. Only one allocation is performed, in the constructor.
- *   When reading and writing, the return value of the method allows checking if
- *   the ring buffer is empty or full.
- * - We always keep the read index at least one element ahead of the write
- *   index, so we can distinguish between an empty and a full ring buffer: an
- *   empty ring buffer is when the write index is at the same position as the
- *   read index. A full buffer is when the write index is exactly one position
- *   before the read index.
- * - We synchronize updates to the read index after having read the data, and
- *   the write index after having written the data. This means that the each
- *   thread can only touch a portion of the buffer that is not touched by the
- *   other thread.
- * - Callers are expected to provide buffers. When writing to the queue,
- *   elements are copied into the internal storage from the buffer passed in.
- *   When reading from the queue, the user is expected to provide a buffer.
- *   Because this is a ring buffer, data might not be contiguous in memory,
- *   providing an external buffer to copy into is an easy way to have linear
- *   data for further processing.
- */
-template <typename T>
-class ring_buffer_base
-{
-public:
-  /**
-   * Constructor for a ring buffer.
-   *
-   * This performs an allocation, but is the only allocation that will happen
-   * for the life time of a `ring_buffer_base`.
-   *
-   * @param capacity The maximum number of element this ring buffer will hold.
-   */
-  ring_buffer_base(int capacity)
-    /* One more element to distinguish from empty and full buffer. */
-    : capacity_(capacity + 1)
-  {
-    assert(storage_capacity() <
-           std::numeric_limits<int>::max() / 2 &&
-           "buffer too large for the type of index used.");
-    assert(capacity_ > 0);
-
-    data_.reset(new T[storage_capacity()]);
-    /* If this queue is using atomics, initializing those members as the last
-     * action in the constructor acts as a full barrier, and allow capacity() to
-     * be thread-safe. */
-    write_index_ = 0;
-    read_index_ = 0;
-  }
-  /**
-   * Push `count` zero or default constructed elements in the array.
-   *
-   * Only safely called on the producer thread.
-   *
-   * @param count The number of elements to enqueue.
-   * @return The number of element enqueued.
-   */
-  int enqueue_default(int count)
-  {
-    return enqueue(nullptr, count);
-  }
-  /**
-   * @brief Put an element in the queue
-   *
-   * Only safely called on the producer thread.
-   *
-   * @param element The element to put in the queue.
-   *
-   * @return 1 if the element was inserted, 0 otherwise.
-   */
-  int enqueue(T& element)
-  {
-    return enqueue(&element, 1);
-  }
-  /**
-   * Push `count` elements in the ring buffer.
-   *
-   * Only safely called on the producer thread.
-   *
-   * @param elements a pointer to a buffer containing at least `count` elements.
-   * If `elements` is nullptr, zero or default constructed elements are enqueued.
-   * @param count The number of elements to read from `elements`
-   * @return The number of elements successfully coped from `elements` and inserted
-   * into the ring buffer.
-   */
-  int enqueue(T * elements, int count)
-  {
-#ifndef NDEBUG
-    assert_correct_thread(producer_id);
-#endif
-
-    int rd_idx = read_index_.load(std::memory_order::memory_order_relaxed);
-    int wr_idx = write_index_.load(std::memory_order::memory_order_relaxed);
-
-    if (full_internal(rd_idx, wr_idx)) {
-      return 0;
-    }
-
-    int to_write =
-      std::min(available_write_internal(rd_idx, wr_idx), count);
-
-    /* First part, from the write index to the end of the array. */
-    int first_part = std::min(storage_capacity() - wr_idx,
-                                          to_write);
-    /* Second part, from the beginning of the array */
-    int second_part = to_write - first_part;
-
-    if (elements) {
-      Copy(data_.get() + wr_idx, elements, first_part);
-      Copy(data_.get(), elements + first_part, second_part);
-    } else {
-      ConstructDefault(data_.get() + wr_idx, first_part);
-      ConstructDefault(data_.get(), second_part);
-    }
-
-    write_index_.store(increment_index(wr_idx, to_write), std::memory_order::memory_order_release);
-
-    return to_write;
-  }
-  /**
-   * Retrieve at most `count` elements from the ring buffer, and copy them to
-   * `elements`, if non-null.
-   *
-   * Only safely called on the consumer side.
-   *
-   * @param elements A pointer to a buffer with space for at least `count`
-   * elements. If `elements` is `nullptr`, `count` element will be discarded.
-   * @param count The maximum number of elements to dequeue.
-   * @return The number of elements written to `elements`.
-   */
-  int dequeue(T * elements, int count)
-  {
-#ifndef NDEBUG
-    assert_correct_thread(consumer_id);
-#endif
-
-    int wr_idx = write_index_.load(std::memory_order::memory_order_acquire);
-    int rd_idx = read_index_.load(std::memory_order::memory_order_relaxed);
-
-    if (empty_internal(rd_idx, wr_idx)) {
-      return 0;
-    }
-
-    int to_read =
-      std::min(available_read_internal(rd_idx, wr_idx), count);
-
-    int first_part = std::min(storage_capacity() - rd_idx, to_read);
-    int second_part = to_read - first_part;
-
-    if (elements) {
-      Copy(elements, data_.get() + rd_idx, first_part);
-      Copy(elements + first_part, data_.get(), second_part);
-    }
-
-    read_index_.store(increment_index(rd_idx, to_read), std::memory_order::memory_order_relaxed);
-
-    return to_read;
-  }
-  /**
-   * Get the number of available element for consuming.
-   *
-   * Only safely called on the consumer thread.
-   *
-   * @return The number of available elements for reading.
-   */
-  int available_read() const
-  {
-#ifndef NDEBUG
-    assert_correct_thread(consumer_id);
-#endif
-    return available_read_internal(read_index_.load(std::memory_order::memory_order_relaxed),
-                                   write_index_.load(std::memory_order::memory_order_relaxed));
-  }
-  /**
-   * Get the number of available elements for consuming.
-   *
-   * Only safely called on the producer thread.
-   *
-   * @return The number of empty slots in the buffer, available for writing.
-   */
-  int available_write() const
-  {
-#ifndef NDEBUG
-    assert_correct_thread(producer_id);
-#endif
-    return available_write_internal(read_index_.load(std::memory_order::memory_order_relaxed),
-                                    write_index_.load(std::memory_order::memory_order_relaxed));
-  }
-  /**
-   * Get the total capacity, for this ring buffer.
-   *
-   * Can be called safely on any thread.
-   *
-   * @return The maximum capacity of this ring buffer.
-   */
-  int capacity() const
-  {
-    return storage_capacity() - 1;
-  }
-  /**
-   * Reset the consumer and producer thread identifier, in case the thread are
-   * being changed. This has to be externally synchronized. This is no-op when
-   * asserts are disabled.
-   */
-  void reset_thread_ids()
-  {
-#ifndef NDEBUG
-    consumer_id = producer_id = std::thread::id();
-#endif
-  }
-private:
-  /** Return true if the ring buffer is empty.
-   *
-   * @param read_index the read index to consider
-   * @param write_index the write index to consider
-   * @return true if the ring buffer is empty, false otherwise.
-   **/
-  bool empty_internal(int read_index,
-                      int write_index) const
-  {
-    return write_index == read_index;
-  }
-  /** Return true if the ring buffer is full.
-   *
-   * This happens if the write index is exactly one element behind the read
-   * index.
-   *
-   * @param read_index the read index to consider
-   * @param write_index the write index to consider
-   * @return true if the ring buffer is full, false otherwise.
-   **/
-  bool full_internal(int read_index,
-                     int write_index) const
-  {
-    return (write_index + 1) % storage_capacity() == read_index;
-  }
-  /**
-   * Return the size of the storage. It is one more than the number of elements
-   * that can be stored in the buffer.
-   *
-   * @return the number of elements that can be stored in the buffer.
-   */
-  int storage_capacity() const
-  {
-    return capacity_;
-  }
-  /**
-   * Returns the number of elements available for reading.
-   *
-   * @return the number of available elements for reading.
-   */
-  int
-  available_read_internal(int read_index,
-                          int write_index) const
-  {
-    if (write_index >= read_index) {
-      return write_index - read_index;
-    } else {
-      return write_index + storage_capacity() - read_index;
-    }
-  }
-  /**
-   * Returns the number of empty elements, available for writing.
-   *
-   * @return the number of elements that can be written into the array.
-   */
-  int
-  available_write_internal(int read_index,
-                           int write_index) const
-  {
-    /* We substract one element here to always keep at least one sample
-     * free in the buffer, to distinguish between full and empty array. */
-    int rv = read_index - write_index - 1;
-    if (write_index >= read_index) {
-      rv += storage_capacity();
-    }
-    return rv;
-  }
-  /**
-   * Increments an index, wrapping it around the storage.
-   *
-   * @param index a reference to the index to increment.
-   * @param increment the number by which `index` is incremented.
-   * @return the new index.
-   */
-  int
-  increment_index(int index, int increment) const
-  {
-    assert(increment >= 0);
-    return (index + increment) % storage_capacity();
-  }
-  /**
-   * @brief This allows checking that enqueue (resp. dequeue) are always called
-   * by the right thread.
-   *
-   * @param id the id of the thread that has called the calling method first.
-   */
-#ifndef NDEBUG
-  static void assert_correct_thread(std::thread::id& id)
-  {
-    if (id == std::thread::id()) {
-      id = std::this_thread::get_id();
-      return;
-    }
-    assert(id == std::this_thread::get_id());
-  }
-#endif
-  /** Index at which the oldest element is at, in samples. */
-  std::atomic<int> read_index_;
-  /** Index at which to write new elements. `write_index` is always at
-   * least one element ahead of `read_index_`. */
-  std::atomic<int> write_index_;
-  /** Maximum number of elements that can be stored in the ring buffer. */
-  const int capacity_;
-  /** Data storage */
-  std::unique_ptr<T[]> data_;
-#ifndef NDEBUG
-  /** The id of the only thread that is allowed to read from the queue. */
-  mutable std::thread::id consumer_id;
-  /** The id of the only thread that is allowed to write from the queue. */
-  mutable std::thread::id producer_id;
-#endif
-};
-
-/**
- * Adapter for `ring_buffer_base` that exposes an interface in frames.
- */
-template <typename T>
-class audio_ring_buffer_base
-{
-public:
-  /**
-   * @brief Constructor.
-   *
-   * @param channel_count       Number of channels.
-   * @param capacity_in_frames  The capacity in frames.
-   */
-  audio_ring_buffer_base(int channel_count, int capacity_in_frames)
-    : channel_count(channel_count)
-    , ring_buffer(frames_to_samples(capacity_in_frames))
-  {
-    assert(channel_count > 0);
-  }
-  /**
-   * @brief Enqueue silence.
-   *
-   * Only safely called on the producer thread.
-   *
-   * @param frame_count The number of frames of silence to enqueue.
-   * @return  The number of frames of silence actually written to the queue.
-   */
-  int enqueue_default(int frame_count)
-  {
-    return samples_to_frames(ring_buffer.enqueue(nullptr, frames_to_samples(frame_count)));
-  }
-  /**
-   * @brief Enqueue `frames_count` frames of audio.
-   *
-   * Only safely called from the producer thread.
-   *
-   * @param [in] frames If non-null, the frames to enqueue.
-   *                    Otherwise, silent frames are enqueued.
-   * @param frame_count The number of frames to enqueue.
-   *
-   * @return The number of frames enqueued
-   */
-
-  int enqueue(T * frames, int frame_count)
-  {
-    return samples_to_frames(ring_buffer.enqueue(frames, frames_to_samples(frame_count)));
-  }
-
-  /**
-   * @brief Removes `frame_count` frames from the buffer, and
-   *        write them to `frames` if it is non-null.
-   *
-   * Only safely called on the consumer thread.
-   *
-   * @param frames      If non-null, the frames are copied to `frames`.
-   *                    Otherwise, they are dropped.
-   * @param frame_count The number of frames to remove.
-   *
-   * @return  The number of frames actually dequeud.
-   */
-  int dequeue(T * frames, int frame_count)
-  {
-    return samples_to_frames(ring_buffer.dequeue(frames, frames_to_samples(frame_count)));
-  }
-  /**
-   * Get the number of available frames of audio for consuming.
-   *
-   * Only safely called on the consumer thread.
-   *
-   * @return The number of available frames of audio for reading.
-   */
-  int available_read() const
-  {
-    return samples_to_frames(ring_buffer.available_read());
-  }
-  /**
-   * Get the number of available frames of audio for consuming.
-   *
-   * Only safely called on the producer thread.
-   *
-   * @return The number of empty slots in the buffer, available for writing.
-   */
-  int available_write() const
-  {
-    return samples_to_frames(ring_buffer.available_write());
-  }
-  /**
-   * Get the total capacity, for this ring buffer.
-   *
-   * Can be called safely on any thread.
-   *
-   * @return The maximum capacity of this ring buffer.
-   */
-  int capacity() const
-  {
-    return samples_to_frames(ring_buffer.capacity());
-  }
-private:
-  /**
-   * @brief Frames to samples conversion.
-   *
-   * @param frames The number of frames.
-   *
-   * @return  A number of samples.
-   */
-  int frames_to_samples(int frames) const
-  {
-    return frames * channel_count;
-  }
-  /**
-   * @brief Samples to frames conversion.
-   *
-   * @param samples The number of samples.
-   *
-   * @return  A number of frames.
-   */
-  int samples_to_frames(int samples) const
-  {
-    return samples / channel_count;
-  }
-  /** Number of channels of audio that will stream through this ring buffer. */
-  int channel_count;
-  /** The underlying ring buffer that is used to store the data. */
-  ring_buffer_base<T> ring_buffer;
-};
-
-/**
- * Lock-free instantiation of the `ring_buffer_base` type. This is safe to use
- * from two threads, one producer, one consumer (that never change role),
- * without explicit synchronization.
- */
-template<typename T>
-using lock_free_queue = ring_buffer_base<T>;
-/**
- * Lock-free instantiation of the `audio_ring_buffer` type. This is safe to use
- * from two threads, one producer, one consumer (that never change role),
- * without explicit synchronization.
- */
-template<typename T>
-using lock_free_audio_ring_buffer = audio_ring_buffer_base<T>;
-
-#endif // CUBEB_RING_BUFFER_H