chromium/chrome/browser/extensions/api/image_writer_private/operation.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 CHROME_BROWSER_EXTENSIONS_API_IMAGE_WRITER_PRIVATE_OPERATION_H_
#define CHROME_BROWSER_EXTENSIONS_API_IMAGE_WRITER_PRIVATE_OPERATION_H_

#include <stdint.h>

#include <memory>

#include "base/files/file.h"
#include "base/files/scoped_temp_dir.h"
#include "base/functional/callback.h"
#include "base/hash/md5.h"
#include "base/memory/ref_counted_memory.h"
#include "base/memory/weak_ptr.h"
#include "base/task/sequenced_task_runner.h"
#include "base/task/task_traits.h"
#include "build/build_config.h"
#include "build/chromeos_buildflags.h"
#include "chrome/common/extensions/api/image_writer_private.h"
#include "extensions/common/extension_id.h"

#if BUILDFLAG(IS_CHROMEOS_ASH)
#include "chromeos/ash/components/disks/disk_mount_manager.h"
#endif

image_writer_api;

namespace base {
class FilePath;
}  // namespace base

namespace extensions {
namespace image_writer {

const int kProgressComplete = …;

class OperationManager;

#if !BUILDFLAG(IS_CHROMEOS_ASH)
class ImageWriterUtilityClient;
#endif

// Encapsulates an operation being run on behalf of the
// OperationManager.  Construction of the operation does not start
// anything.  The operation's Start method should be called to start it, and
// then the Cancel method will stop it.  The operation will call back to the
// OperationManager periodically or on any significant event.
//
// Each stage of the operation is generally divided into multiple phases with
// Start() being the first phase and Complete() being the last. All phases
// except Complete() run on blocking thread and Complete() runs on the UI
// thread.
//
// TODO(haven): This class is current refcounted because it is owned by the
// OperationManager on the UI thread but needs to do work on blocking threads.
// There is probably a better way to organize this so that it can be represented
// by a WeakPtr, but those are not thread-safe.  Additionally, if destruction is
// done on the UI thread then that causes problems if any of the fields were
// allocated/accessed on the blocking thread.  http://crbug.com/344713
class Operation : public base::RefCountedThreadSafe<Operation> { … };

}  // namespace image_writer
}  // namespace extensions

#endif  // CHROME_BROWSER_EXTENSIONS_API_IMAGE_WRITER_PRIVATE_OPERATION_H_