chromium/media/base/async_destroy_video_decoder.h

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_BASE_ASYNC_DESTROY_VIDEO_DECODER_H_
#define MEDIA_BASE_ASYNC_DESTROY_VIDEO_DECODER_H_

#include <memory>
#include <type_traits>
#include "media/base/video_decoder.h"

namespace media {

// Some VideoDecoder implementations must do non-synchronous cleanup before
// they are destroyed. This wrapper implementation allows a VideoDecoder
// to schedule its own cleanup tasks before its memory is released.
// The underlying type must implement a static
// `DestroyAsync(std::unique_ptr<T>)` function which fires any pending
// callbacks, stops and destroys the decoder. After this call, external
// resources (e.g. raw pointers) held by the decoder might be invalidated
// immediately. So if the decoder is destroyed asynchronously (e.g. DeleteSoon),
// external resources must be released in this call.
template <typename T>
class AsyncDestroyVideoDecoder final : public VideoDecoder { … };

}  // namespace media

#endif  // MEDIA_BASE_ASYNC_DESTROY_VIDEO_DECODER_H_