device/usb/scoped_libusb_device_ref.h

// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef DEVICE_USB_SCOPED_LIBUSB_DEVICE_REF_H_
#define DEVICE_USB_SCOPED_LIBUSB_DEVICE_REF_H_

#include "base/macros.h"
#include "base/memory/scoped_refptr.h"

struct libusb_device;

namespace device {

class UsbContext;

// This class owns a reference to a libusb_device as well as a reference to
// the libusb_context. The libusb_context must outlive any libusb_device
// instances created from it.
class ScopedLibusbDeviceRef {
 public:
  ScopedLibusbDeviceRef(libusb_device* device,
                        scoped_refptr<UsbContext> context);
  ScopedLibusbDeviceRef(ScopedLibusbDeviceRef&& other);
  ~ScopedLibusbDeviceRef();

  libusb_device* get() const { return device_; }

  scoped_refptr<UsbContext> GetContext() const { return context_; }

  void Reset();
  bool IsValid() const;

 private:
  libusb_device* device_;
  scoped_refptr<UsbContext> context_;

  DISALLOW_COPY_AND_ASSIGN(ScopedLibusbDeviceRef);
};

bool operator==(const ScopedLibusbDeviceRef& ref, libusb_device* device);

}  // namespace device

#endif  // DEVICE_USB_SCOPED_LIBUSB_DEVICE_REF_H_