Move device/usb classes from the FILE thread to UI thread.

device/usb/usb_device_handle_impl.h

 // Copyright 2014 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_IMPL_H_
 #define DEVICE_USB_USB_DEVICE_HANDLE_IMPL_H_
 
 #include <map>
 #include <set>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
-#include "base/memory/weak_ptr.h"
-#include "base/strings/string16.h"
 #include "base/threading/thread_checker.h"
 #include "device/usb/usb_device_handle.h"
-#include "net/base/io_buffer.h"
 #include "third_party/libusb/src/libusb/libusb.h"
 
 namespace base {
-class SingleThreadTaskRunner;
+class SequencedTaskRunner;
+}
+
+namespace net {
+class IOBuffer;
 }
 
 namespace device {
 
 class UsbContext;
 struct UsbConfigDescriptor;
 class UsbDeviceImpl;
 
 typedef libusb_device_handle* PlatformUsbDeviceHandle;
 typedef libusb_iso_packet_descriptor* PlatformUsbIsoPacketDescriptor;
 typedef libusb_transfer* PlatformUsbTransferHandle;
 
 // UsbDeviceHandle class provides basic I/O related functionalities.
 class UsbDeviceHandleImpl : public UsbDeviceHandle {
  public:
   scoped_refptr<UsbDevice> GetDevice() const override;
   void Close() override;
-  bool SetConfiguration(int configuration_value) override;
-  bool ClaimInterface(int interface_number) override;
+  void SetConfiguration(int configuration_value,
+                        const ResultCallback& callback) override;
+  void ClaimInterface(int interface_number,
+                      const ResultCallback& callback) override;
   bool ReleaseInterface(int interface_number) override;
-  bool SetInterfaceAlternateSetting(int interface_number,
-                                    int alternate_setting) override;
-  bool ResetDevice() override;
-  bool GetStringDescriptor(uint8 string_id, base::string16* string) override;
+  void SetInterfaceAlternateSetting(int interface_number,
+                                    int alternate_setting,
+                                    const ResultCallback& callback) override;
+  void ResetDevice(const ResultCallback& callback) override;
 
   void ControlTransfer(UsbEndpointDirection direction,
                        TransferRequestType request_type,
                        TransferRecipient recipient,
                        uint8 request,
                        uint16 value,
                        uint16 index,
                        net::IOBuffer* buffer,
                        size_t length,
                        unsigned int timeout,
-                       const UsbTransferCallback& callback) override;
+                       const TransferCallback& callback) override;
 
   void BulkTransfer(UsbEndpointDirection direction,
                     uint8 endpoint,
                     net::IOBuffer* buffer,
                     size_t length,
                     unsigned int timeout,
-                    const UsbTransferCallback& callback) override;
+                    const TransferCallback& callback) override;
 
   void InterruptTransfer(UsbEndpointDirection direction,
                          uint8 endpoint,
                          net::IOBuffer* buffer,
                          size_t length,
                          unsigned int timeout,
-                         const UsbTransferCallback& callback) override;
+                         const TransferCallback& callback) override;
 
   void IsochronousTransfer(UsbEndpointDirection direction,
                            uint8 endpoint,
                            net::IOBuffer* buffer,
                            size_t length,
                            unsigned int packets,
                            unsigned int packet_length,
                            unsigned int timeout,
-                           const UsbTransferCallback& callback) override;
+                           const TransferCallback& callback) override;
 
   PlatformUsbDeviceHandle handle() const { return handle_; }
 
  protected:
   friend class UsbDeviceImpl;
 
-  // This constructor is called by UsbDevice.
-  UsbDeviceHandleImpl(scoped_refptr<UsbContext> context,
-                      scoped_refptr<UsbDeviceImpl> device,
-                      PlatformUsbDeviceHandle handle);
+  // This constructor is called by UsbDeviceImpl.
+  UsbDeviceHandleImpl(
+      scoped_refptr<UsbContext> context,
+      scoped_refptr<UsbDeviceImpl> device,
+      PlatformUsbDeviceHandle handle,
+      scoped_refptr<base::SequencedTaskRunner> blocking_task_runner);
 
   ~UsbDeviceHandleImpl() override;
 
  private:
   friend class Transfer;
 
   class InterfaceClaimer;
   class Transfer;
 
+  void SetConfigurationOnBlockingThread(PlatformUsbDeviceHandle handle,
+                                        int configuration_value,
+                                        const ResultCallback& callback);
+  void SetConfigurationComplete(bool success, const ResultCallback& callback);
+  void ClaimInterfaceOnBlockingThread(PlatformUsbDeviceHandle handle,
+                                      int interface_number,
+                                      const ResultCallback& callback);
+  void ClaimInterfaceComplete(int interface_number,
+                              bool success,
+                              const ResultCallback& callback);
+  void SetInterfaceAlternateSettingOnBlockingThread(
+      PlatformUsbDeviceHandle handle,
+      int interface_number,
+      int alternate_setting,
+      const ResultCallback& callback);
+  void SetInterfaceAlternateSettingComplete(int interface_number,
+                                            int alternate_setting,
+                                            bool success,
+                                            const ResultCallback& callback);
+  void ResetDeviceOnBlockingThread(PlatformUsbDeviceHandle handle,
+                                   const ResultCallback& callback);
+  void ResetDeviceComplete(bool success, const ResultCallback& callback);
+
   // Refresh endpoint_map_ after ClaimInterface, ReleaseInterface and
   // SetInterfaceAlternateSetting.
   void RefreshEndpointMap();
 
   // Look up the claimed interface by endpoint. Return NULL if the interface
   // of the endpoint is not found.
   scoped_refptr<InterfaceClaimer> GetClaimedInterfaceForEndpoint(
       unsigned char endpoint);
 
-  // If the device's task runner is on the current thread then the transfer will
-  // be submitted directly, otherwise a task to do so it posted. The callback
-  // will be called on the current message loop of the thread where this
-  // function was called.
-  void PostOrSubmitTransfer(scoped_ptr<Transfer> transfer);
-
   // Submits a transfer and starts tracking it. Retains the buffer and copies
   // the completion callback until the transfer finishes, whereupon it invokes
   // the callback then releases the buffer.
   void SubmitTransfer(scoped_ptr<Transfer> transfer);
 
-  // Invokes the callbacks associated with a given transfer, and removes it from
-  // the in-flight transfer set.
-  void CompleteTransfer(scoped_ptr<Transfer> transfer);
-
-  bool GetSupportedLanguages();
+  // Removes the transfer from the in-flight transfer set and invokes the
+  // completion callback.
+  void TransferComplete(Transfer* transfer, const base::Closure& callback);
 
   // Informs the object to drop internal references.
   void InternalClose();
 
   scoped_refptr<UsbDeviceImpl> device_;
 
   PlatformUsbDeviceHandle handle_;
 
-  std::vector<uint16> languages_;
-  std::map<uint8, base::string16> strings_;
-
   typedef std::map<int, scoped_refptr<InterfaceClaimer>> ClaimedInterfaceMap;
   ClaimedInterfaceMap claimed_interfaces_;
 
   // This set holds weak pointers to pending transfers.
   std::set<Transfer*> transfers_;
 
   // A map from endpoints to interfaces
   typedef std::map<int, int> EndpointMap;
   EndpointMap endpoint_map_;
 
   // Retain the UsbContext so that the platform context will not be destroyed
   // before this handle.
   scoped_refptr<UsbContext> context_;
 
-  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+  scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
 
   base::ThreadChecker thread_checker_;
-  base::WeakPtrFactory<UsbDeviceHandleImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UsbDeviceHandleImpl);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_USB_USB_DEVICE_HANDLE_IMPL_H_