Add support for reading USB descriptors to the new Windows backend.

device/usb/usb_device_handle_win.h

+// Copyright 2017 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_USB_DEVICE_HANDLE_WIN_H_
+#define DEVICE_USB_USB_DEVICE_HANDLE_WIN_H_
+
+#include <list>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "base/threading/thread_checker.h"
+#include "base/win/scoped_handle.h"
+#include "device/usb/usb_device_handle.h"
+
+namespace base {
+class SequencedTaskRunner;
+class SingleThreadTaskRunner;
+}
+
+namespace net {
+class IOBuffer;
+}
+
+namespace device {
+
+class UsbDeviceWin;
+
+// UsbDeviceHandle class provides basic I/O related functionalities.
+class UsbDeviceHandleWin : public UsbDeviceHandle {
+ public:
+  scoped_refptr<UsbDevice> GetDevice() const override;
+  void Close() override;
+  void SetConfiguration(int configuration_value,
+                        const ResultCallback& callback) override;
+  void ClaimInterface(int interface_number,
+                      const ResultCallback& callback) override;
+  void ReleaseInterface(int interface_number,
+                        const ResultCallback& callback) override;
+  void SetInterfaceAlternateSetting(int interface_number,
+                                    int alternate_setting,
+                                    const ResultCallback& callback) override;
+  void ResetDevice(const ResultCallback& callback) override;
+  void ClearHalt(uint8_t endpoint, const ResultCallback& callback) override;
+
+  void ControlTransfer(UsbEndpointDirection direction,
+                       TransferRequestType request_type,
+                       TransferRecipient recipient,
+                       uint8_t request,
+                       uint16_t value,
+                       uint16_t index,
+                       scoped_refptr<net::IOBuffer> buffer,
+                       size_t length,
+                       unsigned int timeout,
+                       const TransferCallback& callback) override;
+
+  void IsochronousTransferIn(
+      uint8_t endpoint,
+      const std::vector<uint32_t>& packet_lengths,
+      unsigned int timeout,
+      const IsochronousTransferCallback& callback) override;
+
+  void IsochronousTransferOut(
+      uint8_t endpoint,
+      scoped_refptr<net::IOBuffer> buffer,
+      const std::vector<uint32_t>& packet_lengths,
+      unsigned int timeout,
+      const IsochronousTransferCallback& callback) override;
+
+  void GenericTransfer(UsbEndpointDirection direction,
+                       uint8_t endpoint_number,
+                       scoped_refptr<net::IOBuffer> buffer,
+                       size_t length,
+                       unsigned int timeout,
+                       const TransferCallback& callback) override;
+  const UsbInterfaceDescriptor* FindInterfaceByEndpoint(
+      uint8_t endpoint_address) override;
+
+ protected:
+  friend class UsbDeviceWin;
+
+  // Constructor used to build a connection to the device's parent hub.
+  UsbDeviceHandleWin(
+      scoped_refptr<UsbDeviceWin> device,
+      base::win::ScopedHandle handle,
+      scoped_refptr<base::SequencedTaskRunner> blocking_task_runner);
+
+  ~UsbDeviceHandleWin() override;
+
+ private:
+  class Request;
+
+  std::unique_ptr<Request> UnlinkRequest(Request* request);
+  void GotNodeConnectionInformation(const TransferCallback& callback,
+                                    void* node_connection_info,
+                                    scoped_refptr<net::IOBuffer> buffer,
+                                    size_t buffer_length,
+                                    Request* request_ptr,
+                                    DWORD win32_result,
+                                    size_t bytes_transferred);
+  void GotDescriptorFromNodeConnection(
+      const TransferCallback& callback,
+      scoped_refptr<net::IOBuffer> request_buffer,
+      scoped_refptr<net::IOBuffer> original_buffer,
+      size_t original_buffer_length,
+      Request* request_ptr,
+      DWORD win32_result,
+      size_t bytes_transferred);
+
+  base::ThreadChecker thread_checker_;
+
+  scoped_refptr<UsbDeviceWin> device_;
+
+  base::win::ScopedHandle hub_handle_;
+  std::list<std::unique_ptr<Request>> requests_;

[Ken Rockot(use gerrit already), 2017/02/17 20:27:07]

nit: Maybe worth documenting that hub_handle_ must outlive requests_.

Also consider using a map<Request*, std::unique_ptr<Request>>?

[Reilly Grant (use Gerrit), 2017/02/18 00:45:49]

Done.

+
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+  scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
+
+  base::WeakPtrFactory<UsbDeviceHandleWin> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(UsbDeviceHandleWin);
+};
+
+}  // namespace device
+
+#endif  // DEVICE_USB_USB_DEVICE_HANDLE_WIN_H_